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Blobe, Gerard Conrad

Overview:

Our laboratory focuses on transforming growth factor-ß (TGF-ß) superfamily signal transduction pathways, and specifically, the role of these pathways in cancer biology. The TGF-ß superfamily is comprised of a number of polypeptide growth factors, including TGF-βs, bone morphogenetic proteins (BMPs) and activin) that regulate growth, differentiation and morphogenesis in a cell and context specific manner. TGF-ß and the TGF-ß signaling pathway have a dichotomous role in cancer biology, as both tumor-suppressor genes (presumably as regulators of cellular proliferation, differentiation and apoptosis) and as tumor promoters (presumably as regulators of cellular motility, adhesion, angiogenesis and the immune system). This dichotomy of TGF-ß function remains a fundamental problem in the field both in terms of understanding the mechanism of action of the TGF-ß pathway, and directly impacting our ability to target this pathway for the chemoprevention or treatment of human cancers. Resistance to the tumor suppressor effects of TGF-ß is also a common feature of epithelial-derived human cancers (breast, colon, lung, pancreatic, prostate), however, mechanisms for TGF-ß resistance remain undefined in the majority of cases. TGF-ß regulates cellular processes by binding to three high affinity cell surface receptors, the type I, type II, and type III receptors. Recent studies by our laboratory and others have established the type III TGF-ß receptor as a critical mediator/regulator of TGF-ß signaling. Specifically we have demonstrated that regulating type III TGF-ß receptor expression levels is sufficient to regulate TGF-ß signaling, and that decreased type III receptor expression is a common phenomenon in human cancers, resulting in cancer progression. The role of the type III TGF-ß receptor and type III TGF-ß receptor-interacting proteins in TGF-ß signaling and cancer biology and the epithelial to mesenchymal transition that occurs in human breast, colon and pancreatic cancers are currently being investigated using a multidisciplinary approach.
TGF-ß and the TGF-ß superfamily signaling pathways also have an important role in vascular biology. Indeed, mutations in two endothelial specific TGF-ß superfamily receptors, endoglin and ALK-1 (a type I receptor in the TGF-ß family), are responsible for the human vascular disease, hereditary hemorrhagic telangiectasia (HHT), and mice which lack expression of these receptors are embryonic lethal due to defects in angiogenesis. In addition, endoglin expression is potently up regulated during tumor-induced angiogenesis. In endothelial cells, TGF-ß signals through the type I TGF-ß receptor (ALK-5) or through ALK-1, to mediate opposing effects on endothelial cell proliferation and migration. However, the role of endoglin in regulating the balance in signaling between these pathways is unknown. Our laboratory has identified the nuclear hormone receptor, LXR-ß, as a protein that binds to activated ALK-1, is phosphorylated by ALK-1 and modulates ALK-1 signaling,establishing a novel signaling pathway downstream of ALK-1. Investigations in our laboratory have also revealed important functions for the cytoplasmic domain of endoglin, which is highly homologous to the cytoplasmic domain of the type III TGF-ß receptor. Studies are currently underway to further elucidate the signal transduction pathway downstream from these receptors and to establish their role in regulating tumor-induced angiogenesis. The ultimate goal of these studies is the ability to target the TGF-ß pathway for the chemoprevention or treatment of human cancers.
As endoglin and the type III TGF-ß receptors are both "co-receptors," a class of poorly understood cell surface receptors that bind ligand but are not thought to signal directly, another focus for the laboratory is establishing the role of these co-receptors in orchestrating signaling in physiological and pathophysiological settings.

Positions:

Professor of Medicine

Medicine, Medical Oncology
School of Medicine

Professor of Pharmacology and Cancer Biology

Pharmacology & Cancer Biology
School of Medicine

Member of the Duke Cancer Institute

Duke Cancer Institute
School of Medicine

Education:

M.D. 1995

M.D. — Duke University

Ph.D. 1995

Ph.D. — Duke University

News:

Grants:

Translational Research in Surgical Oncology

Administered By
Surgery, Surgical Sciences
AwardedBy
National Institutes of Health
Role
Mentor
Start Date
January 01, 2002
End Date
August 31, 2021

Melanoma-mediated Dendritic Cell Tolerization and Immune Evasion

Administered By
Medicine, Medical Oncology
AwardedBy
National Institutes of Health
Role
Mentor
Start Date
August 04, 2015
End Date
July 31, 2020

Organization and Function of Cellular Structure

Administered By
Basic Science Departments
AwardedBy
National Institutes of Health
Role
Mentor
Start Date
July 01, 1975
End Date
June 30, 2020

Pharmacological Sciences Training Program

Administered By
Pharmacology & Cancer Biology
AwardedBy
National Institutes of Health
Role
Participating Faculty Member
Start Date
July 01, 1975
End Date
June 30, 2020

Pharmacology Industry Internships for Ph.D. Students

Administered By
Pharmacology & Cancer Biology
AwardedBy
American Society for Pharmacology and Experimental Therapeutics
Role
Participating Faculty Member
Start Date
January 01, 2017
End Date
December 31, 2019

Fibulin-3 as a Novel Biomarker and Trget in the Breast Tumor Microenvironment

Administered By
Medicine, Medical Oncology
AwardedBy
Susan G. Komen Breast Cancer Foundation
Role
Mentor
Start Date
December 01, 2015
End Date
November 30, 2018

A Novel Function for ALK4 in Suppressing Breast Cancer Progression

Administered By
Medicine, Medical Oncology
AwardedBy
Susan G. Komen Breast Cancer Foundation
Role
Principal Investigator
Start Date
August 20, 2015
End Date
August 19, 2018

Training Program in Developmental and Stem Cell Biology

Administered By
Basic Science Departments
AwardedBy
National Institutes of Health
Role
Mentor
Start Date
May 01, 2001
End Date
October 31, 2017

Dissecting ALK4 Function in Cancer Progression

Administered By
Medicine, Medical Oncology
AwardedBy
National Institutes of Health
Role
Principal Investigator
Start Date
July 01, 2015
End Date
June 30, 2017

Medical Scientist Training Program

Administered By
School of Medicine
AwardedBy
National Institutes of Health
Role
Mentor
Start Date
July 01, 1997
End Date
June 30, 2017

The Role of Type III TGF-beta Receptor in ALK1-mediated Tumor Angiogenesis

Administered By
Medicine, Medical Oncology
AwardedBy
National Institutes of Health
Role
Principal Investigator
Start Date
June 01, 2015
End Date
May 31, 2017

Role of Type III TGF-beta Receptor Shedding in Lung Cancer Initiation and Progression

Administered By
Medicine, Medical Oncology
AwardedBy
National Institutes of Health
Role
Principal Investigator
Start Date
April 01, 2016
End Date
March 31, 2017

Therapeutic Targeting of the TGF-BSignaling Axis to Modulate the Tumor Immune Microenvironment and Enhance Melanoma Immu

Administered By
Medicine, Medical Oncology
AwardedBy
Melanoma Research Alliance
Role
Mentor
Start Date
November 01, 2013
End Date
January 31, 2017

Epigenetic Regulation of Neuroblast Differentiation

Administered By
Medicine, Medical Oncology
AwardedBy
National Institutes of Health
Role
Principal Investigator
Start Date
March 01, 2015
End Date
November 01, 2016

Endoglin Regulates Biology and Signal Transduction in Vascular Smooth Muscle Cells

Administered By
Medicine, Medical Oncology
AwardedBy
HHT Foundation International, Inc.
Role
Mentor
Start Date
June 01, 2015
End Date
August 31, 2016

2014 Gertrude B. Elion Mentored Medical Student Research Award

Administered By
Medicine, Medical Oncology
AwardedBy
Triangle Community Foundation
Role
Principal Investigator
Start Date
June 01, 2013
End Date
May 31, 2016

The Role of Type III TGF-beta Receptor in the Fibrotic Tumor Stroma

Administered By
Medicine, Medical Oncology
AwardedBy
National Institutes of Health
Role
Principal Investigator
Start Date
August 01, 2013
End Date
April 30, 2016

Cancer Biology Training Grant

Administered By
Pharmacology & Cancer Biology
AwardedBy
National Cancer Institute
Role
Mentor
Start Date
July 01, 1993
End Date
March 31, 2016

Alex's Million Mile Unrestricted Grant

Administered By
Medicine, Medical Oncology
AwardedBy
Alex's Lemonade Stand
Role
Principal Investigator
Start Date
March 02, 2015
End Date
March 01, 2016

Stroma Biology Identifies Heparin as a Differentiating Agent in Neuroblastoma

Administered By
Medicine, Medical Oncology
AwardedBy
Alex's Lemonade Stand
Role
Principal Investigator
Start Date
December 31, 2013
End Date
December 30, 2015

JUN PROTEINS IN EPIDERMAL HOMEOSTASIS AND NEOPLASIA

Administered By
Dermatology
AwardedBy
National Institutes of Health
Role
Collaborator
Start Date
August 09, 2010
End Date
May 31, 2015

Function of TbRIII as a BMP Co-receptor in Human Cancer

Administered By
Medicine, Medical Oncology
AwardedBy
National Institutes of Health
Role
Principal Investigator
Start Date
July 09, 2009
End Date
April 30, 2015

Role of TbRIII in Regulating Motility and Invasion

Administered By
Medicine, Medical Oncology
AwardedBy
National Institutes of Health
Role
Principal Investigator
Start Date
July 09, 2009
End Date
April 30, 2015

Alternative splicing and epithelial-mesenchymal plasticity in prostate tumors

Administered By
Molecular Genetics and Microbiology
AwardedBy
National Institutes of Health
Role
Consultant
Start Date
December 01, 2008
End Date
November 30, 2014

Role of TGF beta Receptor III Localization in Breast Cancer Progression

Administered By
Medicine, Medical Oncology
AwardedBy
National Institutes of Health
Role
Principal Investigator
Start Date
September 30, 2011
End Date
September 29, 2014

The Role of Stroma-derived Soluble TbetaRIII in Neuroblastoma

Administered By
Medicine, Medical Oncology
AwardedBy
National Institutes of Health
Role
Principal Investigator
Start Date
April 01, 2012
End Date
March 31, 2014

Role of Type III TGF-b Receptor in Mediating Immunosuppression During Breast Cancer Progression

Administered By
Medicine, Medical Oncology
AwardedBy
Department of Defense
Role
Mentor
Start Date
September 30, 2010
End Date
October 29, 2013

Anti-VEGF in Tumors & Wounds: Efficacy vs Toxicity

Administered By
Medicine, Medical Oncology
AwardedBy
National Institutes of Health
Role
Co Investigator
Start Date
April 16, 2006
End Date
February 28, 2012

Elucidating the Role of T_RIII in Breast Carcinogenesis

Administered By
Medicine, Medical Oncology
AwardedBy
National Institutes of Health
Role
Principal Investigator
Start Date
February 16, 2009
End Date
February 15, 2012

Endoglin Regulates Endothelial Survival and Capillary Tube Stability

Administered By
Medicine, Medical Oncology
AwardedBy
National Institutes of Health
Role
Mentor
Start Date
May 20, 2011
End Date
August 31, 2011

Multispectral Imaging Flow Cytometer Core

Administered By
Medicine, Medical Oncology
AwardedBy
National Institutes of Health
Role
Principal Investigator
Start Date
March 04, 2010
End Date
March 03, 2011

Novel Roles for Endoglin in TGF-b Signaling

Administered By
Medicine, Medical Oncology
AwardedBy
National Institutes of Health
Role
Principal Investigator
Start Date
June 06, 2008
End Date
June 05, 2010

Type III TGF-beta Receptor as a Mediator/Reg. of Sign

Administered By
Medicine, Medical Oncology
AwardedBy
National Institutes of Health
Role
Principal Investigator
Start Date
July 01, 2005
End Date
April 30, 2010

Role of the TGF-Beta Receptor in Cancer Biology

Administered By
Medicine, Medical Oncology
AwardedBy
National Institutes of Health
Role
Principal Investigator
Start Date
May 01, 2004
End Date
August 01, 2009

ALK-1 and Endoglin Signaling in Endothelial Cells

Administered By
Medicine, Medical Oncology
AwardedBy
National Institutes of Health
Role
Principal Investigator
Start Date
April 01, 2004
End Date
April 30, 2009

Biomarker Studies for Novel Anti-Cancer Agents

Administered By
Medicine, Medical Oncology
AwardedBy
National Institutes of Health
Role
Consultant
Start Date
May 28, 2003
End Date
February 29, 2008

CLN3: Modulation of Apoptosis and Ceramide Levels

Administered By
Pediatrics, Neurology
AwardedBy
National Institutes of Health
Role
Investigator
Start Date
February 01, 2003
End Date
January 31, 2008

Role of the Type III TGF-b Receptor in TGF-b Signaling

Administered By
Medicine, Medical Oncology
AwardedBy
National Institutes of Health
Role
Principal Investigator
Start Date
July 11, 2002
End Date
June 30, 2005
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Publications:

Phase I study of pazopanib plus TH-302 in advanced solid tumors.

To define the maximum tolerated dose (MTD), recommended phase II dose (RPTD), and assess safety and tolerability for the combination of pazopanib plus TH-302, an investigational hypoxia-activated prodrug (HAP), in adult patients with advanced solid tumors.This was an open-label, non-randomized, single-center, phase I trial consisting 2 stages. Stage 1 was a standard "3 + 3" dose escalation design to determine safety and the RPTD for TH-302 plus pazopanib combination. Stage 2 was an expanded cohort to better describe the tolerability and toxicity profile at the MTD. Pazopanib was orally dosed at 800 mg daily on days 1-28 for all cohorts. TH-302 was administered intravenously on days 1, 8 and 15 of a 28-day cycle at doses of 340 mg/m2 (cohort 1) or 480 mg/m2 (cohort 2). Dose limiting toxicity (DLT) was assessed in the first 28-day cycle. Efficacy was assessed every 2 cycles.Thirty patients were enrolled between December 2011 and September 2013. In the dose escalation stage, 7 patients were enrolled in the 340 mg/m2 TH-302 cohort and 6 patients in the 480 mg/m2 TH-302 cohort. Ten patients were evaluable for DLT. DLTs included grade 2 intolerable esophagitis (n = 1) in the 340 mg/m2 TH-302 cohort, and grade 3 vaginal inflammation (n = 1) and grade 3 neutropenia with grade 3 thrombocytopenia (n = 1, same patient) in the 480 mg/m2 TH-302 cohort. The 340 mg/m2 TH-302 cohort was determined to be MTD and RPTD. The most common treatment-related adverse events were hematologic (anemia, neutropenia, and thrombocytopenia), nausea/vomiting, palmar-plantar erythrodysesthesia syndrome, constipation, fatigue, mucositis, anorexia, pain, and hypertension. Partial response (PR) was observed in 10% (n = 3) of patients, stable disease (SD) in 57% (n = 17), and progressive disease (PD) in 23% (n = 7). Due to toxicity, 3 patients were discontinued from study drug prior to first radiographic assessment but were included in these calculations. Disease control ≥6 months was observed in 37% of patients (n = 11).The RPTD for this novel combination is pazopanib 800 mg daily on days 1-28 plus TH-302 340 mg/m2 on days 1, 8 and 15 of each 28-day cycle. Preliminary activity was seen in treatment-refractory cancers and supports potential value of co-targeting tumor angiogenesis and tumor hypoxia.

Authors
Riedel, RF; Meadows, KL; Lee, PH; Morse, MA; Uronis, HE; Blobe, GC; George, DJ; Crawford, J; Niedzwiecki, D; Rushing, CN; Arrowood, CC; Hurwitz, HI
MLA Citation
Riedel, RF, Meadows, KL, Lee, PH, Morse, MA, Uronis, HE, Blobe, GC, George, DJ, Crawford, J, Niedzwiecki, D, Rushing, CN, Arrowood, CC, and Hurwitz, HI. "Phase I study of pazopanib plus TH-302 in advanced solid tumors." Cancer chemotherapy and pharmacology 79.3 (March 2017): 611-619.
PMID
28238078
Source
epmc
Published In
Cancer Chemotherapy and Pharmacology
Volume
79
Issue
3
Publish Date
2017
Start Page
611
End Page
619
DOI
10.1007/s00280-017-3256-2

Heparin-binding epidermal growth factor-like growth factor promotes neuroblastoma differentiation.

High-risk neuroblastoma is characterized by undifferentiated neuroblasts and low Schwannian stroma content. The tumor stroma contributes to the suppression of tumor growth by releasing soluble factors that promote neuroblast differentiation. Here we identify heparin-binding epidermal growth factor-like growth factor (HBEGF) as a potent prodifferentiating factor in neuroblastoma. HBEGF mRNA expression is decreased in human neuroblastoma tumors compared with benign tumors, with loss correlating with decreased survival. HBEGF protein is expressed only in stromal compartments of human neuroblastoma specimens, with tissue from high-stage disease containing very little stroma or HBEGF expression. In 3 human neuroblastoma cell lines (SK-N-AS, SK-N-BE2, and SH-SY5Y), soluble HBEGF is sufficient to promote neuroblast differentiation and decrease proliferation. Heparan sulfate proteoglycans and heparin derivatives further enhance HBEGF-induced differentiation by forming a complex with the epidermal growth factor receptor, leading to activation of the ERK1/2 and STAT3 pathways and up-regulation of the inhibitor of DNA binding transcription factor. These data support a role for loss of HBEGF in the neuroblastoma tumor microenvironment in neuroblastoma pathogenesis.-Gaviglio, A. L., Knelson, E. H., Blobe, G. C. Heparin-binding epidermal growth factor-like growth factor promotes neuroblastoma differentiation.

Authors
Gaviglio, AL; Knelson, EH; Blobe, GC
MLA Citation
Gaviglio, AL, Knelson, EH, and Blobe, GC. "Heparin-binding epidermal growth factor-like growth factor promotes neuroblastoma differentiation." FASEB journal : official publication of the Federation of American Societies for Experimental Biology (February 7, 2017).
PMID
28174207
Source
epmc
Published In
The FASEB journal : official publication of the Federation of American Societies for Experimental Biology
Publish Date
2017
DOI
10.1096/fj.201600828r

Dichotomous roles of TGF-β in human cancer.

Transforming growth factor-β (TGF-β) mediates numerous biological processes, including embryonic development and the maintenance of cellular homeostasis in a context-dependent manner. Consistent with its central role in maintaining cellular homeostasis, inhibition of TGF-β signaling results in disruption of normal homeostatic processes and subsequent carcinogenesis, defining the TGF-β signaling pathway as a tumor suppressor. However, once carcinogenesis is initiated, the TGF-β signaling pathway promotes cancer progression. This dichotomous function of the TGF-β signaling pathway is mediated through altering effects on both the cancer cells, by inducing apoptosis and inhibiting proliferation, and the tumor microenvironment, by promoting angiogenesis and inhibiting immunosurveillance. Current studies support inhibition of TGF-β signaling either alone, or in conjunction with anti-angiogenic therapy or immunotherapy as a promising strategy for the treatment of human cancers.

Authors
Huang, JJ; Blobe, GC
MLA Citation
Huang, JJ, and Blobe, GC. "Dichotomous roles of TGF-β in human cancer." Biochemical Society transactions 44.5 (October 2016): 1441-1454.
PMID
27911726
Source
epmc
Published In
Biochemical Society transactions
Volume
44
Issue
5
Publish Date
2016
Start Page
1441
End Page
1454
DOI
10.1042/bst20160065

TGF-β-induced stromal CYR61 promotes resistance to gemcitabine in pancreatic ductal adenocarcinoma through downregulation of the nucleoside transporters hENT1 and hCNT3.

Pancreatic ductal adenocarcinoma (PDAC) is a lethal cancer in part due to inherent resistance to chemotherapy, including the first-line drug gemcitabine. Although low expression of the nucleoside transporters hENT1 and hCNT3 that mediate cellular uptake of gemcitabine has been linked to gemcitabine resistance, the mechanisms regulating their expression in the PDAC tumor microenvironment are largely unknown. Here, we report that the matricellular protein cysteine-rich angiogenic inducer 61 (CYR61) negatively regulates the nucleoside transporters hENT1 and hCNT3. CRISPR/Cas9-mediated knockout of CYR61 increased expression of hENT1 and hCNT3, increased cellular uptake of gemcitabine and sensitized PDAC cells to gemcitabine-induced apoptosis. In PDAC patient samples, expression of hENT1 and hCNT3 negatively correlates with expression of CYR61 We demonstrate that stromal pancreatic stellate cells (PSCs) are a source of CYR61 within the PDAC tumor microenvironment. Transforming growth factor-β (TGF-β) induces the expression of CYR61 in PSCs through canonical TGF-β-ALK5-Smad2/3 signaling. Activation of TGF-β signaling or expression of CYR61 in PSCs promotes resistance to gemcitabine in PDAC cells in an in vitro co-culture assay. Our results identify CYR61 as a TGF-β-induced stromal-derived factor that regulates gemcitabine sensitivity in PDAC and suggest that targeting CYR61 may improve chemotherapy response in PDAC patients.

Authors
Hesler, RA; Huang, JJ; Starr, MD; Treboschi, VM; Bernanke, AG; Nixon, AB; McCall, SJ; White, RR; Blobe, GC
MLA Citation
Hesler, RA, Huang, JJ, Starr, MD, Treboschi, VM, Bernanke, AG, Nixon, AB, McCall, SJ, White, RR, and Blobe, GC. "TGF-β-induced stromal CYR61 promotes resistance to gemcitabine in pancreatic ductal adenocarcinoma through downregulation of the nucleoside transporters hENT1 and hCNT3." Carcinogenesis (September 7, 2016).
PMID
27604902
Source
epmc
Published In
Carcinogenesis
Publish Date
2016

Abstract 1182: Heparin-binding epidermal growth factor-like growth factor is a pro-differentiating factor in neuroblastoma

Authors
Gaviglio, AL; Blobe, GC
MLA Citation
Gaviglio, AL, and Blobe, GC. "Abstract 1182: Heparin-binding epidermal growth factor-like growth factor is a pro-differentiating factor in neuroblastoma." July 15, 2016.
Source
crossref
Published In
Cancer Research
Volume
76
Issue
14 Supplement
Publish Date
2016
Start Page
1182
End Page
1182
DOI
10.1158/1538-7445.AM2016-1182

An Automated High-throughput Array Microscope for Cancer Cell Mechanics.

Changes in cellular mechanical properties correlate with the progression of metastatic cancer along the epithelial-to-mesenchymal transition (EMT). Few high-throughput methodologies exist that measure cell compliance, which can be used to understand the impact of genetic alterations or to screen the efficacy of chemotherapeutic agents. We have developed a novel array high-throughput microscope (AHTM) system that combines the convenience of the standard 96-well plate with the ability to image cultured cells and membrane-bound microbeads in twelve independently-focusing channels simultaneously, visiting all wells in eight steps. We use the AHTM and passive bead rheology techniques to determine the relative compliance of human pancreatic ductal epithelial (HPDE) cells, h-TERT transformed HPDE cells (HPNE), and four gain-of-function constructs related to EMT. The AHTM found HPNE, H-ras, Myr-AKT, and Bcl2 transfected cells more compliant relative to controls, consistent with parallel tests using atomic force microscopy and invasion assays, proving the AHTM capable of screening for changes in mechanical phenotype.

Authors
Cribb, JA; Osborne, LD; Beicker, K; Psioda, M; Chen, J; O'Brien, ET; Taylor Ii, RM; Vicci, L; Hsiao, JP-L; Shao, C; Falvo, M; Ibrahim, JG; Wood, KC; Blobe, GC; Superfine, R
MLA Citation
Cribb, JA, Osborne, LD, Beicker, K, Psioda, M, Chen, J, O'Brien, ET, Taylor Ii, RM, Vicci, L, Hsiao, JP-L, Shao, C, Falvo, M, Ibrahim, JG, Wood, KC, Blobe, GC, and Superfine, R. "An Automated High-throughput Array Microscope for Cancer Cell Mechanics." Scientific reports 6 (June 6, 2016): 27371-.
PMID
27265611
Source
epmc
Published In
Scientific Reports
Volume
6
Publish Date
2016
Start Page
27371
DOI
10.1038/srep27371

Fibulin-3 is a novel TGF-β pathway inhibitor in the breast cancer microenvironment.

Transforming growth factor-β (TGF-β) is an important regulator of breast cancer progression. However, how the breast cancer microenvironment regulates TGF-β signaling during breast cancer progression remains largely unknown. Here, we identified fibulin-3 as a secreted protein in the breast cancer microenvironment, which efficiently inhibits TGF-β signaling in both breast cancer cells and endothelial cells. Mechanistically, fibulin-3 interacts with the type I TGF-β receptor (TβRI) to block TGF-β induced complex formation of TβRI with the type II TGF-β receptor (TβRII) and subsequent downstream TGF-β signaling. Fibulin-3 expression decreases during breast cancer progression, with low fibulin-3 levels correlating with a poorer prognosis. Functionally, high fibulin-3 levels inhibited TGF-β-induced epithelial-mesenchymal transition (EMT), migration, invasion and endothelial permeability, while loss of fibulin-3 expression/function promoted these TGF-β-mediated effects. Further, restoring fibulin-3 expression in breast cancer cells inhibited TGF-β signaling, breast cancer cell EMT, invasion and metastasis in vivo. These studies provide a novel mechanism for how TGF-β signaling is regulated by the tumor microenvironment, and provide insight into targeting the TGF-β signaling pathway in human breast cancer patients.

Authors
Tian, H; Liu, J; Chen, J; Gatza, ML; Blobe, GC
MLA Citation
Tian, H, Liu, J, Chen, J, Gatza, ML, and Blobe, GC. "Fibulin-3 is a novel TGF-β pathway inhibitor in the breast cancer microenvironment." Oncogene 34.45 (November 2015): 5635-5647.
PMID
25823021
Source
epmc
Published In
Oncogene: Including Oncogene Reviews
Volume
34
Issue
45
Publish Date
2015
Start Page
5635
End Page
5647
DOI
10.1038/onc.2015.13

Dalantercept

© 2015 Prous Science, S.A.U. or its licensors. All rights reserved.The TGF-b superfamily receptor activin receptor-like kinase 1 (ALK-1) has essential roles in regulating angiogenesis during development and homeostasis, as well as pathophysiological tumor angiogenesis. Dalantercept is a soluble chimeric protein composed of the ALK-1 extracellular domain fused to the human Fc domain. Dalantercept acts as a ligand trap to prevent the activation of endogenous ALK-1 by bone morphogenetic proteins 9/10. In preclinical models, dalantercept inhibits tumor growth and enhances the efficacy of cytotoxic chemotherapy. In early clinical development, dalantercept as a single agent has had a promising disease control rate. Dalantercept has a favorable safety profile, with fluid retention and edema being the most common side effects. Current studies are investigating the role of dalantercept with cytotoxic chemotherapy and other targeted therapies.

Authors
Hector-Greene, ME; Blobe, GC
MLA Citation
Hector-Greene, ME, and Blobe, GC. "Dalantercept." Drugs of the Future 40.10 (October 1, 2015): 633-637.
Source
scopus
Published In
Drugs of the future
Volume
40
Issue
10
Publish Date
2015
Start Page
633
End Page
637
DOI
10.1358/dof.2015.040.10.2386993

TβRIII independently binds type I and type II TGF-β receptors to inhibit TGF-β signaling.

Transforming growth factor-β (TGF-β) receptor oligomerization has important roles in signaling. Complex formation among type I and type II (TβRI and TβRII) TGF-β receptors is well characterized and is essential for signal transduction. However, studies on their interactions with the type III TGF-β coreceptor (TβRIII) in live cells and their effects on TGF-β signaling are lacking. Here we investigated the homomeric and heteromeric interactions of TβRIII with TβRI and TβRII in live cells by combining IgG-mediated patching/immobilization of a given TGF-β receptor with fluorescence recovery after photobleaching studies on the lateral diffusion of a coexpressed receptor. Our studies demonstrate that TβRIII homo-oligomerization is indirect and depends on its cytoplasmic domain interactions with scaffold proteins (mainly GIPC). We show that TβRII and TβRI bind independently to TβRIII, whereas TβRIII augments TβRI/TβRII association, suggesting that TβRI and TβRII bind to TβRIII simultaneously but not as a complex. TβRIII expression inhibited TGF-β-mediated Smad2/3 signaling in MDA-MB-231 cell lines, an effect that depended on the TβRIII cytoplasmic domain and did not require TβRIII ectodomain shedding. We propose that independent binding of TβRI and TβRII to TβRIII competes with TβRI/TβRII signaling complex formation, thus inhibiting TGF-β-mediated Smad signaling.

Authors
Tazat, K; Hector-Greene, M; Blobe, GC; Henis, YI
MLA Citation
Tazat, K, Hector-Greene, M, Blobe, GC, and Henis, YI. "TβRIII independently binds type I and type II TGF-β receptors to inhibit TGF-β signaling." Molecular biology of the cell 26.19 (October 2015): 3535-3545.
PMID
26269580
Source
epmc
Published In
Molecular Biology of the Cell
Volume
26
Issue
19
Publish Date
2015
Start Page
3535
End Page
3545
DOI
10.1091/mbc.e15-04-0203

Regulation of TGF-β receptor hetero-oligomerization and signaling by endoglin.

Complex formation among transforming growth factor-β (TGF-β) receptors and its modulation by coreceptors represent an important level of regulation for TGF-β signaling. Oligomerization of ALK5 and the type II TGF-β receptor (TβRII) has been thoroughly investigated, both in vitro and in intact cells. However, such studies, especially in live cells, are missing for the endothelial cell coreceptor endoglin and for the ALK1 type I receptor, which enables endothelial cells to respond to TGF-β by activation of both Smad2/3 and Smad1/5/8. Here we combined immunoglobulin G-mediated immobilization of one cell-surface receptor with lateral mobility studies of a coexpressed receptor by fluorescence recovery after photobleaching (FRAP) to demonstrate that endoglin forms stable homodimers that function as a scaffold for binding TβRII, ALK5, and ALK1. ALK1 and ALK5 bind to endoglin with differential dependence on TβRII, which plays a major role in recruiting ALK5 to the complex. Signaling data indicate a role for the quaternary receptor complex in regulating the balance between TGF-β signaling to Smad1/5/8 and to Smad2/3.

Authors
Pomeraniec, L; Hector-Greene, M; Ehrlich, M; Blobe, GC; Henis, YI
MLA Citation
Pomeraniec, L, Hector-Greene, M, Ehrlich, M, Blobe, GC, and Henis, YI. "Regulation of TGF-β receptor hetero-oligomerization and signaling by endoglin." Molecular biology of the cell 26.17 (September 2015): 3117-3127.
PMID
26157163
Source
epmc
Published In
Molecular Biology of the Cell
Volume
26
Issue
17
Publish Date
2015
Start Page
3117
End Page
3127
DOI
10.1091/mbc.e15-02-0069

Angiotensin II stimulates canonical TGF-β signaling pathway through angiotensin type 1 receptor to induce granulation tissue contraction.

Hypertrophic scar contraction (HSc) is caused by granulation tissue contraction propagated by myofibroblast and fibroblast migration and contractility. Identifying the stimulants that promote migration and contractility is key to mitigating HSc. Angiotensin II (AngII) promotes migration and contractility of heart, liver, and lung fibroblasts; thus, we investigated the mechanisms of AngII in HSc. Human scar and unwounded dermis were immunostained for AngII receptors angiotensin type 1 receptor (AT1 receptor) and angiotensin type 2 receptor (AT2 receptor) and analyzed for AT1 receptor expression using Western blot. In vitro assays of fibroblast contraction and migration under AngII stimulation were conducted with AT1 receptor, AT2 receptor, p38, Jun N-terminal kinase (JNK), MEK, and activin receptor-like kinase 5 (ALK5) antagonism. Excisional wounds were created on AT1 receptor KO and wild-type (WT) mice treated with AngII ± losartan and ALK5 and JNK inhibitors SB-431542 and SP-600125, respectively. Granulation tissue contraction was quantified, and wounds were analyzed by immunohistochemistry. AT1 receptor expression was increased in scar, but not unwounded tissue. AngII induced fibroblast contraction and migration through AT1 receptor. Cell migration was inhibited by ALK5 and JNK, but not p38 or MEK blockade. In vivo experiments determined that absence of AT1 receptor and chemical AT1 receptor antagonism diminished granulation tissue contraction while AngII stimulated wound contraction. AngII granulation tissue contraction was diminished by ALK5 inhibition, but not JNK. AngII promotes granulation tissue contraction through AT1 receptor and downstream canonical transforming growth factor (TGF)-β signaling pathway, ALK5. Further understanding the pathogenesis of HSc as an integrated signaling mechanism could improve our approach to establishing effective therapeutic interventions.AT1 receptor expression is increased in scar tissue compared to unwounded tissue. AngII stimulates expression of proteins that confer cell migration and contraction. AngII stimulates fibroblast migration and contraction through AT1 receptor, ALK5, and JNK. AngII-stimulated in vivo granulation tissue contraction is AT1 receptor and ALK5 dependent.

Authors
Ehanire, T; Ren, L; Bond, J; Medina, M; Li, G; Bashirov, L; Chen, L; Kokosis, G; Ibrahim, M; Selim, A; Blobe, GC; Levinson, H
MLA Citation
Ehanire, T, Ren, L, Bond, J, Medina, M, Li, G, Bashirov, L, Chen, L, Kokosis, G, Ibrahim, M, Selim, A, Blobe, GC, and Levinson, H. "Angiotensin II stimulates canonical TGF-β signaling pathway through angiotensin type 1 receptor to induce granulation tissue contraction." March 2015.
PMID
25345602
Source
epmc
Published In
Journal of Molecular Medicine
Volume
93
Issue
3
Publish Date
2015
Start Page
289
End Page
302
DOI
10.1007/s00109-014-1211-9

Erratum to: angiotensin II stimulates canonical TGF-β signaling pathway through angiotensin type 1 receptor to induce granulation tissue contraction.

Authors
Ehanire, T; Ren, L; Bond, J; Medina, M; Li, G; Bashirov, L; Chen, L; Kokosis, G; Ibrahim, M; Selim, A; Blobe, GC; Levinson, H
MLA Citation
Ehanire, T, Ren, L, Bond, J, Medina, M, Li, G, Bashirov, L, Chen, L, Kokosis, G, Ibrahim, M, Selim, A, Blobe, GC, and Levinson, H. "Erratum to: angiotensin II stimulates canonical TGF-β signaling pathway through angiotensin type 1 receptor to induce granulation tissue contraction." Journal of molecular medicine (Berlin, Germany) 93.3 (March 2015): 303-.
PMID
25676696
Source
epmc
Published In
Journal of Molecular Medicine
Volume
93
Issue
3
Publish Date
2015
Start Page
303
DOI
10.1007/s00109-015-1262-6

Erratum to Angiotensin II stimulates canonical TGF-β signaling pathway through angiotensin type 1 receptor to induce granulation tissue contraction (J Mol Med, (2015), 10.1007/s00109-014-1211-9)

Authors
Ehanire, T; Ren, L; Bond, J; Medina, M; Li, G; Bashirov, L; Chen, L; Kokosis, G; Ibrahim, M; Selim, A; Blobe, GC; Levinson, H
MLA Citation
Ehanire, T, Ren, L, Bond, J, Medina, M, Li, G, Bashirov, L, Chen, L, Kokosis, G, Ibrahim, M, Selim, A, Blobe, GC, and Levinson, H. "Erratum to Angiotensin II stimulates canonical TGF-β signaling pathway through angiotensin type 1 receptor to induce granulation tissue contraction (J Mol Med, (2015), 10.1007/s00109-014-1211-9)." Journal of Molecular Medicine 93.3 (January 1, 2015): 303-.
Source
scopus
Published In
Journal of Molecular Medicine
Volume
93
Issue
3
Publish Date
2015
Start Page
303
DOI
10.1007/s00109-015-1262-6

Angiotensin II stimulates canonical TGF-β signaling pathway through angiotensin type 1 receptor to induce granulation tissue contraction

© 2014, Springer-Verlag Berlin Heidelberg.Abstract: Hypertrophic scar contraction (HSc) is caused by granulation tissue contraction propagated by myofibroblast and fibroblast migration and contractility. Identifying the stimulants that promote migration and contractility is key to mitigating HSc. Angiotensin II (AngII) promotes migration and contractility of heart, liver, and lung fibroblasts; thus, we investigated the mechanisms of AngII in HSc. Human scar and unwounded dermis were immunostained for AngII receptors angiotensin type 1 receptor (AT1 receptor) and angiotensin type 2 receptor (AT2 receptor) and analyzed for AT1 receptor expression using Western blot. In vitro assays of fibroblast contraction and migration under AngII stimulation were conducted with AT1 receptor, AT2 receptor, p38, Jun N-terminal kinase (JNK), MEK, and activin receptor-like kinase 5 (ALK5) antagonism. Excisional wounds were created on AT1 receptor KO and wild-type (WT) mice treated with AngII ± losartan and ALK5 and JNK inhibitors SB-431542 and SP-600125, respectively. Granulation tissue contraction was quantified, and wounds were analyzed by immunohistochemistry. AT1 receptor expression was increased in scar, but not unwounded tissue. AngII induced fibroblast contraction and migration through AT1 receptor. Cell migration was inhibited by ALK5 and JNK, but not p38 or MEK blockade. In vivo experiments determined that absence of AT1 receptor and chemical AT1 receptor antagonism diminished granulation tissue contraction while AngII stimulated wound contraction. AngII granulation tissue contraction was diminished by ALK5 inhibition, but not JNK. AngII promotes granulation tissue contraction through AT1 receptor and downstream canonical transforming growth factor (TGF)-β signaling pathway, ALK5. Further understanding the pathogenesis of HSc as an integrated signaling mechanism could improve our approach to establishing effective therapeutic interventions. Key message: AT1 receptor expression is increased in scar tissue compared to unwounded tissue. AngII stimulates expression of proteins that confer cell migration and contraction. AngII stimulates fibroblast migration and contraction through AT1 receptor, ALK5, and JNK. AngII-stimulated in vivo granulation tissue contraction is AT1 receptor and ALK5 dependent.

Authors
Ehanire, T; Ren, L; Bond, J; Medina, M; Li, G; Bashirov, L; Chen, L; Kokosis, G; Ibrahim, M; Selim, A; Blobe, GC; Levinson, H
MLA Citation
Ehanire, T, Ren, L, Bond, J, Medina, M, Li, G, Bashirov, L, Chen, L, Kokosis, G, Ibrahim, M, Selim, A, Blobe, GC, and Levinson, H. "Angiotensin II stimulates canonical TGF-β signaling pathway through angiotensin type 1 receptor to induce granulation tissue contraction." Journal of Molecular Medicine 93.3 (January 1, 2015): 289-302.
Source
scopus
Published In
Journal of Molecular Medicine
Volume
93
Issue
3
Publish Date
2015
Start Page
289
End Page
302
DOI
10.1007/s00109-014-1211-9

TGF-β regulates LARG and GEF-H1 during EMT to affect stiffening response to force and cell invasion.

Recent studies implicate a role for cell mechanics in cancer progression. The epithelial-to-mesenchymal transition (EMT) regulates the detachment of cancer cells from the epithelium and facilitates their invasion into stromal tissue. Although classic EMT hallmarks include loss of cell-cell adhesions, morphology changes, and increased invasion capacity, little is known about the associated mechanical changes. Previously, force application on integrins has been shown to initiate cytoskeletal rearrangements that result in increased cell stiffness and a stiffening response. Here we demonstrate that transforming growth factor β (TGF-β)-induced EMT results in decreased stiffness and loss of the normal stiffening response to force applied on integrins. We find that suppression of the RhoA guanine nucleotide exchange factors (GEFs) LARG and GEF-H1 through TGF-β/ALK5-enhanced proteasomal degradation mediates these changes in cell mechanics and affects EMT-associated invasion. Taken together, our results reveal a functional connection between attenuated stiffness and stiffening response and the increased invasion capacity acquired after TGF-β-induced EMT.

Authors
Osborne, LD; Li, GZ; How, T; O'Brien, ET; Blobe, GC; Superfine, R; Mythreye, K
MLA Citation
Osborne, LD, Li, GZ, How, T, O'Brien, ET, Blobe, GC, Superfine, R, and Mythreye, K. "TGF-β regulates LARG and GEF-H1 during EMT to affect stiffening response to force and cell invasion." Molecular biology of the cell 25.22 (November 2014): 3528-3540.
PMID
25143398
Source
epmc
Published In
Molecular Biology of the Cell
Volume
25
Issue
22
Publish Date
2014
Start Page
3528
End Page
3540
DOI
10.1091/mbc.e14-05-1015

Abstract 2674: Stroma biology identifies heparins as differentiating agents in neuroblastoma

Authors
Knelson, EH; Gaviglio, AL; Nee, JC; Starr, MD; Nixon, AB; Marcus, SG; Blobe, GC
MLA Citation
Knelson, EH, Gaviglio, AL, Nee, JC, Starr, MD, Nixon, AB, Marcus, SG, and Blobe, GC. "Abstract 2674: Stroma biology identifies heparins as differentiating agents in neuroblastoma." October 1, 2014.
Source
crossref
Published In
Cancer Research
Volume
74
Issue
19 Supplement
Publish Date
2014
Start Page
2674
End Page
2674
DOI
10.1158/1538-7445.AM2014-2674

Effects of the combination of TRC105 and bevacizumab on endothelial cell biology.

Endoglin, or CD105, is a cell membrane glycoprotein that is overexpressed on proliferating endothelial cells (EC), including those found in malignancies and choroidal neovascularization. Endoglin mediates the transition from quiescent endothelium, characterized by the relatively dominant state of Smad 2/3 phosphorylation, to active angiogenesis by preferentially phosphorylating Smad 1/5/8. The monoclonal antibody TRC105 binds endoglin with high avidity and is currently being tested in phase 1b and phase 2 clinical trials. In this report, we evaluated the effects of TRC105 on primary human umbilical vascular endothelial cells (HUVEC) as a single agent and in combination with bevacizumab. As single agents, both TRC105 and bevacizumab efficiently blocked HUVEC tube formation, and the combination of both agents achieved even greater levels of inhibition. We further assessed the effects of each drug on various aspects of HUVEC function. While bevacizumab was observed to inhibit HUVEC viability in nutrient-limited medium, TRC105 had little effect on HUVEC viability, either alone or in combination with bevacizumab. Additionally, both drugs inhibited HUVEC migration and induced apoptosis. At the molecular level, TRC105 treatment of HUVEC lead to decreased Smad 1/5/8 phosphorylation in response to BMP-9, a primary ligand for endoglin. Together, these results indicate that TRC105 acts as an effective anti-angiogenic agent alone and in combination with bevacizumab.

Authors
Liu, Y; Tian, H; Blobe, GC; Theuer, CP; Hurwitz, HI; Nixon, AB
MLA Citation
Liu, Y, Tian, H, Blobe, GC, Theuer, CP, Hurwitz, HI, and Nixon, AB. "Effects of the combination of TRC105 and bevacizumab on endothelial cell biology." Investigational new drugs 32.5 (October 2014): 851-859.
PMID
24994097
Source
epmc
Published In
Investigational New Drugs
Volume
32
Issue
5
Publish Date
2014
Start Page
851
End Page
859
DOI
10.1007/s10637-014-0129-y

The role of type III TGF-beta receptor in tumor angiogenesis

Authors
Hector-Greene, ME; Blobe, GC
MLA Citation
Hector-Greene, ME, and Blobe, GC. "The role of type III TGF-beta receptor in tumor angiogenesis." ANGIOGENESIS 17.4 (October 2014): 963-963.
Source
wos-lite
Published In
Angiogenesis
Volume
17
Issue
4
Publish Date
2014
Start Page
963
End Page
963

Role of TGF-β receptor III localization in polarity and breast cancer progression.

The majority of breast cancers originate from the highly polarized luminal epithelial cells lining the breast ducts. However, cell polarity is often lost during breast cancer progression. The type III transforming growth factor-β cell surface receptor (TβRIII) functions as a suppressor of breast cancer progression and also regulates the process of epithelial-to-mesenchymal transition (EMT), a consequence of which is the loss of cell polarity. Many cell surface proteins exhibit polarized expression, being targeted specifically to the apical or basolateral domains. Here we demonstrate that TβRIII is basolaterally localized in polarized breast epithelial cells and that disruption of the basolateral targeting of TβRIII through a single amino acid mutation of proline 826 in the cytosolic domain results in global loss of cell polarity through enhanced EMT. In addition, the mistargeting of TβRIII results in enhanced proliferation, migration, and invasion in vitro and enhanced tumor formation and invasion in an in vivo mouse model of breast carcinoma. These results suggest that proper localization of TβRIII is critical for maintenance of epithelial cell polarity and phenotype and expand the mechanisms by which TβRIII prevents breast cancer initiation and progression.

Authors
Meyer, AE; Gatza, CE; How, T; Starr, M; Nixon, AB; Blobe, GC
MLA Citation
Meyer, AE, Gatza, CE, How, T, Starr, M, Nixon, AB, and Blobe, GC. "Role of TGF-β receptor III localization in polarity and breast cancer progression." Molecular biology of the cell 25.15 (August 2014): 2291-2304.
PMID
24870032
Source
epmc
Published In
Molecular Biology of the Cell
Volume
25
Issue
15
Publish Date
2014
Start Page
2291
End Page
2304
DOI
10.1091/mbc.e14-03-0825

Ectodomain shedding of TβRIII is required for TβRIII-mediated suppression of TGF-β signaling and breast cancer migration and invasion.

The type III transforming growth factor β (TGF-β) receptor (TβRIII), also known as betaglycan, is the most abundantly expressed TGF-β receptor. TβRIII suppresses breast cancer progression by inhibiting migration, invasion, metastasis, and angiogenesis. TβRIII binds TGF-β ligands, with membrane-bound TβRIII presenting ligand to enhance TGF-β signaling. However, TβRIII can also undergo ectodomain shedding, releasing soluble TβRIII, which binds and sequesters ligand to inhibit downstream signaling. To investigate the relative contributions of soluble and membrane-bound TβRIII on TGF-β signaling and breast cancer biology, we defined TβRIII mutants with impaired (ΔShed-TβRIII) or enhanced ectodomain shedding (SS-TβRIII). Inhibiting ectodomain shedding of TβRIII increased TGF-β responsiveness and abrogated TβRIII's ability to inhibit breast cancer cell migration and invasion. Conversely, expressing SS-TβRIII, which increased soluble TβRIII production, decreased TGF-β signaling and increased TβRIII-mediated inhibition of breast cancer cell migration and invasion. Of importance, SS-TβRIII-mediated increases in soluble TβRIII production also reduced breast cancer metastasis in vivo. Taken together, these studies suggest that the ratio of soluble TβRIII to membrane-bound TβRIII is an important determinant for regulation of TβRIII- and TGF-β-mediated signaling and biology.

Authors
Elderbroom, JL; Huang, JJ; Gatza, CE; Chen, J; How, T; Starr, M; Nixon, AB; Blobe, GC
MLA Citation
Elderbroom, JL, Huang, JJ, Gatza, CE, Chen, J, How, T, Starr, M, Nixon, AB, and Blobe, GC. "Ectodomain shedding of TβRIII is required for TβRIII-mediated suppression of TGF-β signaling and breast cancer migration and invasion." Molecular biology of the cell 25.16 (August 2014): 2320-2332.
PMID
24966170
Source
epmc
Published In
Molecular Biology of the Cell
Volume
25
Issue
16
Publish Date
2014
Start Page
2320
End Page
2332
DOI
10.1091/mbc.e13-09-0524

Stromal heparan sulfate differentiates neuroblasts to suppress neuroblastoma growth.

Neuroblastoma prognosis is dependent on both the differentiation state and stromal content of the tumor. Neuroblastoma tumor stroma is thought to suppress neuroblast growth via release of soluble differentiating factors. Here, we identified critical growth-limiting components of the differentiating stroma secretome and designed a potential therapeutic strategy based on their central mechanism of action. We demonstrated that expression of heparan sulfate proteoglycans (HSPGs), including TβRIII, GPC1, GPC3, SDC3, and SDC4, is low in neuroblasts and high in the Schwannian stroma. Evaluation of neuroblastoma patient microarray data revealed an association between TGFBR3, GPC1, and SDC3 expression and improved prognosis. Treatment of neuroblastoma cell lines with soluble HSPGs promoted neuroblast differentiation via FGFR1 and ERK phosphorylation, leading to upregulation of the transcription factor inhibitor of DNA binding 1 (ID1). HSPGs also enhanced FGF2-dependent differentiation, and the anticoagulant heparin had a similar effect, leading to decreased neuroblast proliferation. Dissection of individual sulfation sites identified 2-O, 3-O-desulfated heparin (ODSH) as a differentiating agent, and treatment of orthotopic xenograft models with ODSH suppressed tumor growth and metastasis without anticoagulation. These studies support heparan sulfate signaling intermediates as prognostic and therapeutic neuroblastoma biomarkers and demonstrate that tumor stroma biology can inform the design of targeted molecular therapeutics.

Authors
Knelson, EH; Gaviglio, AL; Nee, JC; Starr, MD; Nixon, AB; Marcus, SG; Blobe, GC
MLA Citation
Knelson, EH, Gaviglio, AL, Nee, JC, Starr, MD, Nixon, AB, Marcus, SG, and Blobe, GC. "Stromal heparan sulfate differentiates neuroblasts to suppress neuroblastoma growth." The Journal of clinical investigation 124.7 (July 2014): 3016-3031.
PMID
24937430
Source
epmc
Published In
Journal of Clinical Investigation
Volume
124
Issue
7
Publish Date
2014
Start Page
3016
End Page
3031
DOI
10.1172/jci74270

Heparan sulfate signaling in cancer.

Heparan sulfate (HS) is a biopolymer consisting of variably sulfated repeating disaccharide units. The anticoagulant heparin is a highly sulfated intracellular variant of HS. HS has demonstrated roles in embryonic development, homeostasis, and human disease via non-covalent interactions with numerous cellular proteins, including growth factors and their receptors. HS can function as a co-receptor by enhancing receptor-complex formation. In other contexts, HS disrupts signaling complexes or serves as a ligand sink. The effects of HS on growth factor signaling are tightly regulated by the actions of sulfyltransferases, sulfatases, and heparanases. HS has important emerging roles in oncogenesis, and heparin derivatives represent potential therapeutic strategies for human cancers. Here we review recent insights into HS signaling in tumor proliferation, angiogenesis, metastasis, and differentiation. A cancer-specific understanding of HS signaling could uncover potential therapeutic targets in this highly actionable signaling network.

Authors
Knelson, EH; Nee, JC; Blobe, GC
MLA Citation
Knelson, EH, Nee, JC, and Blobe, GC. "Heparan sulfate signaling in cancer." Trends in biochemical sciences 39.6 (June 2014): 277-288. (Review)
PMID
24755488
Source
epmc
Published In
Trends in Biochemical Sciences
Volume
39
Issue
6
Publish Date
2014
Start Page
277
End Page
288
DOI
10.1016/j.tibs.2014.03.001

The balance of cell surface and soluble type III TGF-β receptor regulates BMP signaling in normal and cancerous mammary epithelial cells.

Bone morphogenetic proteins (BMPs) are members of the TGF-β superfamily that are over-expressed in breast cancer, with context dependent effects on breast cancer pathogenesis. The type III TGF-β receptor (TβRIII) mediates BMP signaling. While TβRIII expression is lost during breast cancer progression, the role of TβRIII in regulating BMP signaling in normal mammary epithelium and breast cancer cells has not been examined. Restoring TβRIII expression in a 4T1 murine syngeneic model of breast cancer suppressed Smad1/5/8 phosphorylation and inhibited the expression of the BMP transcriptional targets, Id1 and Smad6, in vivo. Similarly, restoring TβRIII expression in human breast cancer cell lines or treatment with sTβRIII inhibited BMP-induced Smad1/5/8 phosphorylation and BMP-stimulated migration and invasion. In normal mammary epithelial cells, shRNA-mediated silencing of TβRIII, TβRIII over-expression, or treatment with sTβRIII inhibited BMP-mediated phosphorylation of Smad1/5/8 and BMP induced migration. Inhibition of TβRIII shedding through treatment with TAPI-2 or expression of a non-shedding TβRIII mutant rescued TβRIII mediated inhibition of BMP induced Smad1/5/8 phosphorylation and BMP induced migration and/or invasion in both in normal mammary epithelial cells and breast cancer cells. Conversely, expression of a TβRIII mutant, which exhibited increased shedding, significantly reduced BMP-mediated Smad1/5/8 phosphorylation, migration, and invasion. These data demonstrate that TβRIII regulates BMP-mediated signaling and biological effects, primarily through the ligand sequestration effects of sTβRIII in normal and cancerous mammary epithelial cells and suggest that the ratio of membrane bound versus sTβRIII plays an important role in mediating these effects.

Authors
Gatza, CE; Elderbroom, JL; Oh, SY; Starr, MD; Nixon, AB; Blobe, GC
MLA Citation
Gatza, CE, Elderbroom, JL, Oh, SY, Starr, MD, Nixon, AB, and Blobe, GC. "The balance of cell surface and soluble type III TGF-β receptor regulates BMP signaling in normal and cancerous mammary epithelial cells." Neoplasia (New York, N.Y.) 16.6 (June 2014): 489-500.
PMID
25077702
Source
epmc
Published In
Neoplasia (New York, N.Y.)
Volume
16
Issue
6
Publish Date
2014
Start Page
489
End Page
500
DOI
10.1016/j.neo.2014.05.008

Combinatorial TGF-beta signaling blockade and anti-CTLA-4 antibody immunotherapy in a murine BRAF(V600E)-PTEN-/-transgenic model of melanoma

Authors
Hanks, BA; Holtzhausen, A; Evans, K; Held, M; Blobe, GC
MLA Citation
Hanks, BA, Holtzhausen, A, Evans, K, Held, M, and Blobe, GC. "Combinatorial TGF-beta signaling blockade and anti-CTLA-4 antibody immunotherapy in a murine BRAF(V600E)-PTEN-/-transgenic model of melanoma." May 20, 2014.
Source
wos-lite
Published In
Journal of Clinical Oncology
Volume
32
Issue
15
Publish Date
2014

Phase I study of dasatinib in combination with capecitabine, oxaliplatin and bevacizumab followed by an expanded cohort in previously untreated metastatic colorectal cancer.

PURPOSE: Dasatinib inhibits src family kinases and has anti-angiogenic properties. We conducted a phase I study of dasatinib, capecitabine, oxaliplatin, and bevacizumab (CapeOx/bevacizumab), with an expansion cohort in metastatic colorectal cancer (CRC). METHODS: Patients were enrolled in a dose escalation cohort to establish the maximum tolerated dose (MTD) and the recommended phase II dose (RP2D). Using a "3 + 3" design, twelve patients with advanced solid tumors received dasatinib (50 mg twice daily or 70 mg daily), capecitabine (850 mg/m(2) twice daily, days 1-14), oxaliplatin (130 mg/m(2) on day 1) and bevacizumab (7.5 mg/kg on day1), every 3 weeks. Ten patients with previously untreated metastatic CRC were then enrolled in an expansion cohort. Activated src (src(act)) expression was measured by immunohistochemistry, using an antibody that selectively recognizes the active conformation of src (clone 28). RESULTS: Twenty-two patients were enrolled between June 2009 and May 2011. Two DLTs were observed in the 50 mg bid dasatinib cohort, and one DLT was observed in the 70 mg daily dasatinib cohort. The MTD and RP2D for dasatinib was 70 mg daily. The most common treatment-related adverse events were fatigue (20; 91 %) and diarrhea (18; 82 %). Biomarker analysis of src(act) expression demonstrated that the overall response rate (ORR) was 75 % (6/8) for patients with high src(act) expression (IHC ≥ 2), compared to 0 % (0/8) for patients with low srcact expression (IHC 0 or 1); (p = 0.007). CONCLUSIONS: The RP2D of dasatinib is 70 mg daily in combination with CapeOx/bevacizumab. High levels of srcact expression may predict those patients most likely to benefit from dasatinib.

Authors
Strickler, JH; McCall, S; Nixon, AB; Brady, JC; Pang, H; Rushing, C; Cohn, A; Starodub, A; Arrowood, C; Haley, S; Meadows, KL; Morse, MA; Uronis, HE; Blobe, GC; Hsu, SD; Zafar, SY; Hurwitz, HI
MLA Citation
Strickler, JH, McCall, S, Nixon, AB, Brady, JC, Pang, H, Rushing, C, Cohn, A, Starodub, A, Arrowood, C, Haley, S, Meadows, KL, Morse, MA, Uronis, HE, Blobe, GC, Hsu, SD, Zafar, SY, and Hurwitz, HI. "Phase I study of dasatinib in combination with capecitabine, oxaliplatin and bevacizumab followed by an expanded cohort in previously untreated metastatic colorectal cancer." Invest New Drugs 32.2 (April 2014): 330-339.
PMID
24173967
Source
pubmed
Published In
Investigational New Drugs
Volume
32
Issue
2
Publish Date
2014
Start Page
330
End Page
339
DOI
10.1007/s10637-013-0042-9

Novel bone morphogenetic protein signaling through Smad2 and Smad3 to regulate cancer progression and development.

The bone morphogenetic protein (BMP) signaling pathways have important roles in embryonic development and cellular homeostasis, with aberrant BMP signaling resulting in a broad spectrum of human disease. We report that BMPs unexpectedly signal through the canonical transforming growth factor β (TGF-β)-responsive Smad2 and Smad3. BMP-induced Smad2/3 signaling occurs preferentially in embryonic cells and transformed cells. BMPs signal to Smad2/3 by stimulating complex formation between the BMP-binding TGF-β superfamily receptors, activin receptor-like kinase (ALK)3/6, and the Smad2/3 phosphorylating receptors ALK5/7. BMP signaling through Smad2 mediates, in part, dorsoventral axis patterning in zebrafish embryos, whereas BMP signaling through Smad3 facilitates cancer cell invasion. Consistent with increased BMP-mediated Smad2/3 signaling during cancer progression, Smad1/5 and Smad 2/3 signaling converge in human cancer specimens. Thus, the signaling mechanisms used by BMPs and TGF-β superfamily receptors are broader than previously appreciated.

Authors
Holtzhausen, A; Golzio, C; How, T; Lee, Y-H; Schiemann, WP; Katsanis, N; Blobe, GC
MLA Citation
Holtzhausen, A, Golzio, C, How, T, Lee, Y-H, Schiemann, WP, Katsanis, N, and Blobe, GC. "Novel bone morphogenetic protein signaling through Smad2 and Smad3 to regulate cancer progression and development." FASEB J 28.3 (March 2014): 1248-1267.
PMID
24308972
Source
pubmed
Published In
The FASEB journal : official publication of the Federation of American Societies for Experimental Biology
Volume
28
Issue
3
Publish Date
2014
Start Page
1248
End Page
1267
DOI
10.1096/fj.13-239178

Safety, pharmacokinetics, pharmacodynamics, and antitumor activity of dalantercept, an activin receptor-like kinase-1 ligand trap, in patients with advanced cancer.

PURPOSE: The angiogenesis inhibitor dalantercept (formerly ACE-041) is a soluble form of activin receptor-like kinase-1 (ALK1) that prevents activation of endogenous ALK1 by bone morphogenetic protein-9 (BMP9) and BMP10 and exhibits antitumor activity in preclinical models. This first-in-human study of dalantercept evaluated its safety, tolerability, pharmacokinetics, pharmacodynamics, and antitumor activity in adults with advanced solid tumors. EXPERIMENTAL DESIGN: Patients in dose-escalating cohorts received dalantercept subcutaneously at one of seven dose levels (0.1-4.8 mg/kg) every 3 weeks until disease progression. Patients in an expansion cohort received dalantercept at 0.8 or 1.6 mg/kg every 3 weeks until disease progression. RESULTS: In 37 patients receiving dalantercept, the most common treatment-related adverse events were peripheral edema, fatigue, and anemia. Edema and fluid retention were dose-limiting toxicities and responded to diuretic therapy. No clinically significant, treatment-related hypertension, proteinuria, gross hemorrhage, or gastrointestinal perforations were observed. One patient with refractory squamous cell cancer of the head and neck had a partial response, and 13 patients had stable disease according to RECISTv1.1, eight of whom had prolonged periods (≥12 weeks) of stable disease. Correlative pharmacodynamic markers included tumor metabolic activity and tumor blood flow, which decreased from baseline in 63% and 82% of evaluable patients, respectively, and telangiectasia in eight patients. CONCLUSION: Dalantercept was well-tolerated at doses up to 1.6 mg/kg, with a safety profile distinct from inhibitors of the VEGF pathway. Dalantercept displayed promising antitumor activity in patients with advanced refractory cancer, and multiple phase II studies are underway.

Authors
Bendell, JC; Gordon, MS; Hurwitz, HI; Jones, SF; Mendelson, DS; Blobe, GC; Agarwal, N; Condon, CH; Wilson, D; Pearsall, AE; Yang, Y; McClure, T; Attie, KM; Sherman, ML; Sharma, S
MLA Citation
Bendell, JC, Gordon, MS, Hurwitz, HI, Jones, SF, Mendelson, DS, Blobe, GC, Agarwal, N, Condon, CH, Wilson, D, Pearsall, AE, Yang, Y, McClure, T, Attie, KM, Sherman, ML, and Sharma, S. "Safety, pharmacokinetics, pharmacodynamics, and antitumor activity of dalantercept, an activin receptor-like kinase-1 ligand trap, in patients with advanced cancer." Clin Cancer Res 20.2 (January 15, 2014): 480-489.
PMID
24173543
Source
pubmed
Published In
Clinical cancer research : an official journal of the American Association for Cancer Research
Volume
20
Issue
2
Publish Date
2014
Start Page
480
End Page
489
DOI
10.1158/1078-0432.CCR-13-1840

Phase i study of dasatinib in combination with capecitabine, oxaliplatin and bevacizumab followed by an expanded cohort in previously untreated metastatic colorectal cancer

Purpose Dasatinib inhibits src family kinases and has anti-angiogenic properties. We conducted a phase I study of dasatinib, capecitabine, oxaliplatin, and bevacizumab (CapeOx/bevacizumab), with an expansion cohort in metastatic colorectal cancer (CRC). Methods Patients were enrolled in a dose escalation cohort to establish the maximum tolerated dose (MTD) and the recommended phase II dose (RP2D). Using a "3 + 3" design, twelve patients with advanced solid tumors received dasatinib (50 mg twice daily or 70 mg daily), capecitabine (850 mg/m2 twice daily, days 1-14), oxaliplatin (130 mg/m2 on day 1) and bevacizumab (7.5 mg/kg on day1), every 3 weeks. Ten patients with previously untreated metastatic CRC were then enrolled in an expansion cohort. Activated src (srcact) expression was measured by immunohistochemistry, using an antibody that selectively recognizes the active conformation of src (clone 28). Results Twenty-two patients were enrolled between June 2009 and May 2011. Two DLTs were observed in the 50 mg bid dasatinib cohort, and one DLT was observed in the 70 mg daily dasatinib cohort. The MTD and RP2D for dasatinib was 70 mg daily. The most common treatment-related adverse events were fatigue (20; 91 %) and diarrhea (18; 82 %). Biomarker analysis of srcact expression demonstrated that the overall response rate (ORR) was 75 % (6/8) for patients with high src act expression (IHC ≥ 2), compared to 0 % (0/8) for patients with low srcact expression (IHC 0 or 1); (p = 0.007). Conclusions The RP2D of dasatinib is 70 mg daily in combination with CapeOx/bevacizumab. High levels of srcact expression may predict those patients most likely to benefit from dasatinib. © 2013 Springer Science+Business Media New York.

Authors
Strickler, JH; McCall, S; Nixon, AB; Brady, JC; Pang, H; Rushing, C; Cohn, A; Starodub, A; Arrowood, C; Haley, S; Meadows, KL; Morse, MA; Uronis, HE; Blobe, GC; Hsu, SD; Zafar, SY; Hurwitz, HI
MLA Citation
Strickler, JH, McCall, S, Nixon, AB, Brady, JC, Pang, H, Rushing, C, Cohn, A, Starodub, A, Arrowood, C, Haley, S, Meadows, KL, Morse, MA, Uronis, HE, Blobe, GC, Hsu, SD, Zafar, SY, and Hurwitz, HI. "Phase i study of dasatinib in combination with capecitabine, oxaliplatin and bevacizumab followed by an expanded cohort in previously untreated metastatic colorectal cancer." Investigational New Drugs 32.2 (January 1, 2014): 330-339.
Source
scopus
Published In
Investigational New Drugs
Volume
32
Issue
2
Publish Date
2014
Start Page
330
End Page
339
DOI
10.1007/s10637-013-0042-9

Heparan sulfate signaling in cancer

Heparan sulfate (HS) is a biopolymer consisting of variably sulfated repeating disaccharide units. The anticoagulant heparin is a highly sulfated intracellular variant of HS. HS has demonstrated roles in embryonic development, homeostasis, and human disease via non-covalent interactions with numerous cellular proteins, including growth factors and their receptors. HS can function as a co-receptor by enhancing receptor-complex formation. In other contexts, HS disrupts signaling complexes or serves as a ligand sink. The effects of HS on growth factor signaling are tightly regulated by the actions of sulfyltransferases, sulfatases, and heparanases. HS has important emerging roles in oncogenesis, and heparin derivatives represent potential therapeutic strategies for human cancers. Here we review recent insights into HS signaling in tumor proliferation, angiogenesis, metastasis, and differentiation. A cancer-specific understanding of HS signaling could uncover potential therapeutic targets in this highly actionable signaling network. © 2014 Elsevier Ltd.

Authors
Knelson, EH; Nee, JC; Blobe, GC
MLA Citation
Knelson, EH, Nee, JC, and Blobe, GC. "Heparan sulfate signaling in cancer." Trends in Biochemical Sciences 39.6 (January 1, 2014): 277-288. (Review)
Source
scopus
Published In
Trends in Biochemical Sciences
Volume
39
Issue
6
Publish Date
2014
Start Page
277
End Page
288
DOI
10.1016/j.tibs.2014.03.001

Type III TGF-β receptor promotes FGF2-mediated neuronal differentiation in neuroblastoma.

Growth factors and their receptors coordinate neuronal differentiation during development, yet their roles in the pediatric tumor neuroblastoma remain unclear. Comparison of mRNA from benign neuroblastic tumors and neuroblastomas revealed that expression of the type III TGF-β receptor (TGFBR3) decreases with advancing stage of neuroblastoma and this loss correlates with a poorer prognosis. Patients with MYCN oncogene amplification and low TGFBR3 expression were more likely to have an adverse outcome. In vitro, TβRIII expression was epigenetically suppressed by MYCN-mediated recruitment of histone deacetylases to regions of the TGFBR3 promoter. TβRIII bound FGF2 and exogenous FGFR1, which promoted neuronal differentiation of neuroblastoma cells. TβRIII and FGF2 cooperated to induce expression of the transcription factor inhibitor of DNA binding 1 via Erk MAPK. TβRIII-mediated neuronal differentiation suppressed cell proliferation in vitro as well as tumor growth and metastasis in vivo. These studies characterize a coreceptor function for TβRIII in FGF2-mediated neuronal differentiation, while identifying potential therapeutic targets and clinical biomarkers for neuroblastoma.

Authors
Knelson, EH; Gaviglio, AL; Tewari, AK; Armstrong, MB; Mythreye, K; Blobe, GC
MLA Citation
Knelson, EH, Gaviglio, AL, Tewari, AK, Armstrong, MB, Mythreye, K, and Blobe, GC. "Type III TGF-β receptor promotes FGF2-mediated neuronal differentiation in neuroblastoma." J Clin Invest 123.11 (November 2013): 4786-4798.
PMID
24216509
Source
pubmed
Published In
Journal of Clinical Investigation
Volume
123
Issue
11
Publish Date
2013
Start Page
4786
End Page
4798
DOI
10.1172/JCI69657

Type III TGF-β receptor downregulation generates an immunotolerant tumor microenvironment.

Cancers subvert the host immune system to facilitate disease progression. These evolved immunosuppressive mechanisms are also implicated in circumventing immunotherapeutic strategies. Emerging data indicate that local tumor-associated DC populations exhibit tolerogenic features by promoting Treg development; however, the mechanisms by which tumors manipulate DC and Treg function in the tumor microenvironment remain unclear. Type III TGF-β receptor (TGFBR3) and its shed extracellular domain (sTGFBR3) regulate TGF-β signaling and maintain epithelial homeostasis, with loss of TGFBR3 expression promoting progression early in breast cancer development. Using murine models of breast cancer and melanoma, we elucidated a tumor immunoevasion mechanism whereby loss of tumor-expressed TGFBR3/sTGFBR3 enhanced TGF-β signaling within locoregional DC populations and upregulated both the immunoregulatory enzyme indoleamine 2,3-dioxygenase (IDO) in plasmacytoid DCs and the CCL22 chemokine in myeloid DCs. Alterations in these DC populations mediated Treg infiltration and the suppression of antitumor immunity. Our findings provide mechanistic support for using TGF-β inhibitors to enhance the efficacy of tumor immunotherapy, indicate that sTGFBR3 levels could serve as a predictive immunotherapy biomarker, and expand the mechanisms by which TGFBR3 suppresses cancer progression to include effects on the tumor immune microenvironment.

Authors
Hanks, BA; Holtzhausen, A; Evans, KS; Jamieson, R; Gimpel, P; Campbell, OM; Hector-Greene, M; Sun, L; Tewari, A; George, A; Starr, M; Nixon, A; Augustine, C; Beasley, G; Tyler, DS; Osada, T; Morse, MA; Ling, L; Lyerly, HK; Blobe, GC
MLA Citation
Hanks, BA, Holtzhausen, A, Evans, KS, Jamieson, R, Gimpel, P, Campbell, OM, Hector-Greene, M, Sun, L, Tewari, A, George, A, Starr, M, Nixon, A, Augustine, C, Beasley, G, Tyler, DS, Osada, T, Morse, MA, Ling, L, Lyerly, HK, and Blobe, GC. "Type III TGF-β receptor downregulation generates an immunotolerant tumor microenvironment." J Clin Invest 123.9 (September 2013): 3925-3940.
Website
http://hdl.handle.net/10161/13297
PMID
23925295
Source
pubmed
Published In
Journal of Clinical Investigation
Volume
123
Issue
9
Publish Date
2013
Start Page
3925
End Page
3940
DOI
10.1172/JCI65745

A phase I study of ABT-510 plus bevacizumab in advanced solid tumors.

Targeting multiple regulators of tumor angiogenesis have the potential to improve treatment efficacy. Bevacizumab is a monoclonal antibody directed against vascular endothelial growth factor and ABT-510 is a synthetic analog of thrombospondin, an endogenous angiogenesis inhibitor. Dual inhibition may result in additional benefit. We evaluated the safety, tolerability, and efficacy of the combination of bevacizumab plus ABT-510 in patients with refractory solid tumors. We also explored the effects of these agents on plasma-based biomarkers and wound angiogenesis. Thirty-four evaluable subjects were enrolled and received study drug. Therapy was well tolerated; minimal treatment-related grade 3/4 toxicity was observed. One patient treated at dose level 1 had a partial response and five other patients treated at the recommended phase II dose had prolonged stable disease for more than 1 year. Biomarker evaluation revealed increased levels of D-dimer, von Willebrand factor, placental growth factor, and stromal-derived factor 1 in response to treatment with the combination of bevacizumab and ABT-510. Data suggest that continued evaluation of combination antiangiogenesis therapies may be clinically useful.

Authors
Uronis, HE; Cushman, SM; Bendell, JC; Blobe, GC; Morse, MA; Nixon, AB; Dellinger, A; Starr, MD; Li, H; Meadows, K; Gockerman, J; Pang, H; Hurwitz, HI
MLA Citation
Uronis, HE, Cushman, SM, Bendell, JC, Blobe, GC, Morse, MA, Nixon, AB, Dellinger, A, Starr, MD, Li, H, Meadows, K, Gockerman, J, Pang, H, and Hurwitz, HI. "A phase I study of ABT-510 plus bevacizumab in advanced solid tumors." Cancer Med 2.3 (June 2013): 316-324.
Website
http://hdl.handle.net/10161/11086
PMID
23930208
Source
pubmed
Published In
Cancer Medicine
Volume
2
Issue
3
Publish Date
2013
Start Page
316
End Page
324
DOI
10.1002/cam4.65

Abstract 5041: The type III TGF-beta receptor promotes FGF2-mediated neuronal differentiation in neuroblastoma.

Authors
Knelson, EH; Gaviglio, AL; Tewari, AK; Armstrong, MB; Nixon, AB; Starr, MD; Mythreye, K; Blobe, GC
MLA Citation
Knelson, EH, Gaviglio, AL, Tewari, AK, Armstrong, MB, Nixon, AB, Starr, MD, Mythreye, K, and Blobe, GC. "Abstract 5041: The type III TGF-beta receptor promotes FGF2-mediated neuronal differentiation in neuroblastoma." April 15, 2013.
Source
crossref
Published In
Cancer Research
Volume
73
Issue
8 Supplement
Publish Date
2013
Start Page
5041
End Page
5041
DOI
10.1158/1538-7445.AM2013-5041

TβRIII/β-arrestin2 regulates integrin α5β1 trafficking, function, and localization in epithelial cells.

The type III TGF-β receptor (TβRIII) is a ubiquitous co-receptor for TGF-β superfamily ligands with roles in suppressing cancer progression, in part through suppressing cell motility. Here we demonstrate that TβRIII promotes epithelial cell adhesion to fibronectin in a β-arrestin2 dependent and TGF-β/BMP independent manner by complexing with active integrin α5β1, and mediating β-arrestin2-dependent α5β1 internalization and trafficking to nascent focal adhesions. TβRIII-mediated integrin α5β1 trafficking regulates cell adhesion and fibronectin fibrillogenesis in epithelial cells, as well as α5 localization in breast cancer patients. We further demonstrate that increased TβRIII expression correlates with increased α5 localization at sites of cell-cell adhesion in breast cancer patients, while higher TβRIII expression is a strong predictor of overall survival in breast cancer patients. These data support a novel, clinically relevant role for TβRIII in regulating integrin α5 localization, reveal a novel crosstalk mechanism between the integrin and TGF-β superfamily signaling pathways and identify β-arrestin2 as a regulator of α5β1 trafficking.

Authors
Mythreye, K; Knelson, EH; Gatza, CE; Gatza, ML; Blobe, GC
MLA Citation
Mythreye, K, Knelson, EH, Gatza, CE, Gatza, ML, and Blobe, GC. "TβRIII/β-arrestin2 regulates integrin α5β1 trafficking, function, and localization in epithelial cells." Oncogene 32.11 (March 14, 2013): 1416-1427.
PMID
22562249
Source
pubmed
Published In
Oncogene: Including Oncogene Reviews
Volume
32
Issue
11
Publish Date
2013
Start Page
1416
End Page
1427
DOI
10.1038/onc.2012.157

Emerging roles of TGF-β co-receptors in human diseaseEmerging roles of TGF-β co-receptors in human disease

© Springer Japan 2013.TGF-β signaling is both regulated and mediated by signaling co- receptors. Several TGF-β co-receptors have been identifi ed including endoglin (CD105), the type III TGF-β receptor (TβRIII, betaglycan), neuropilin-1/2, syndecan- 2, CD109, and LRP1. These co-receptors serve diverse functions including the regulation of ligand access to other TGF-β receptors and receptor traffi cking. The TGF-β coreceptors can also signal directly. The TGF-β co-receptors are broadly expressed, have essential roles in embryonic development, and are frequently altered during disease progression. TGF-β co-receptors regulate cancer initiation and progression through effects on cell growth, migration, invasion, proliferation, and angiogenesis. In addition to their roles in cancer, these co- receptors are dysregulated during development, in vascular disease and fibrotic disorders. Collectively, the TGF-β coreceptors influence disease biology through complex mechanisms involving the regulation of growth factor-dependent and independent signaling events as well as through interactions with diverse scaffolding protein partners.

Authors
Blobe, GC; Meyer, AE; Mythreye, K; Meyer, AE; Mythreye, K; Blobe, GC
MLA Citation
Blobe, GC, Meyer, AE, Mythreye, K, Meyer, AE, Mythreye, K, and Blobe, GC. "Emerging roles of TGF-β co-receptors in human diseaseEmerging roles of TGF-β co-receptors in human disease (PublishedPublished)." TGF-B in Human Disease. January 1, 2013. 59-89.
Source
scopus
Publish Date
2013
Start Page
59
End Page
89
DOI
10.1007/978-4-431-54409-8_3

TGF-beta regulates the Rho GEFs LARG and GEF-H1 during EMT to impact stiffening response to force and cell invasion

Authors
Osborne, LD; Li, G; O'Brien, E; Blobe, GC; Superfine, R; Mythreye, K
MLA Citation
Osborne, LD, Li, G, O'Brien, E, Blobe, GC, Superfine, R, and Mythreye, K. "TGF-beta regulates the Rho GEFs LARG and GEF-H1 during EMT to impact stiffening response to force and cell invasion." MOLECULAR BIOLOGY OF THE CELL 24 (2013).
Source
wos-lite
Published In
Molecular Biology of the Cell
Volume
24
Publish Date
2013

A phase II study of capecitabine, oxaliplatin, and bevacizumab in the treatment of metastatic esophagogastric adenocarcinomas.

BACKGROUND: Esophageal and gastric cancers often present at an advanced stage. Systemic chemotherapy is the mainstay of treatment, but survival with current regimens remains poor. We evaluated the safety, tolerability, and efficacy of the combination capecitabine, oxaliplatin, and bevacizumab in the treatment of metastatic esophagogastric adenocarcinomas. METHODS: Thirty-seven patients with metastatic or unresectable gastric/gastroesophageal junction tumors were enrolled and treated with capecitabine 850 mg/m(2) BID on days 1-14, and oxaliplatin 130 mg/m(2) with bevacizumab 15 mg/kg on day 1 of a 21-day cycle. The primary endpoint was progression-free survival (PFS). Secondary endpoints included response rate (RR) and overall survival (OS). Neuropilin-1 (NRP1) and -2 (NRP2) mRNA expression was evaluated in archived tumor. RESULTS: Thirty-five patients were evaluable for efficacy. Median PFS was 7.2 months; median OS was 10.8 months. RR was estimated at 51.4%. The regimen was tolerable with expected drug class-related toxicities. NRP2 mRNA levels significantly correlated with PFS (p = 0.042) and showed a trend toward significance with OS (p = 0.051). Nonsignificant trends for NRP1 were noted for higher expression levels and worse outcome. CONCLUSIONS: Bevacizumab can be given safely with chemotherapy in patients with metastatic esophagogastric adenocarcinomas. The combination of capecitabine, oxaliplatin, plus bevacizumab has activity comparable to other bevacizumab-containing regimens in metastatic gastroesophageal cancer.

Authors
Uronis, HE; Bendell, JC; Altomare, I; Blobe, GC; Hsu, SD; Morse, MA; Pang, H; Zafar, SY; Conkling, P; Favaro, J; Arrowood, CC; Cushman, SM; Meadows, KL; Brady, JC; Nixon, AB; Hurwitz, HI
MLA Citation
Uronis, HE, Bendell, JC, Altomare, I, Blobe, GC, Hsu, SD, Morse, MA, Pang, H, Zafar, SY, Conkling, P, Favaro, J, Arrowood, CC, Cushman, SM, Meadows, KL, Brady, JC, Nixon, AB, and Hurwitz, HI. "A phase II study of capecitabine, oxaliplatin, and bevacizumab in the treatment of metastatic esophagogastric adenocarcinomas." Oncologist 18.3 (2013): 271-272.
PMID
23485624
Source
pubmed
Published In
The oncologist
Volume
18
Issue
3
Publish Date
2013
Start Page
271
End Page
272
DOI
10.1634/theoncologist.2012-0404

TβRIII/β-arrestin2 regulates integrin α5β1 trafficking, function, and localization in epithelial cells

The type III TGF-β receptor (TβRIII) is a ubiquitous co-receptor for TGF-β superfamily ligands with roles in suppressing cancer progression, in part through suppressing cell motility. Here we demonstrate that TβRIII promotes epithelial cell adhesion to fibronectin in a β-arrestin2 dependent and TGF-β/BMP independent manner by complexing with active integrin α5β1, and mediating β-arrestin2-dependent α5β1 internalization and trafficking to nascent focal adhesions. TβRIII-mediated integrin α5β1 trafficking regulates cell adhesion and fibronectin fibrillogenesis in epithelial cells, as well as α5 localization in breast cancer patients. We further demonstrate that increased TβRIII expression correlates with increased α5 localization at sites of cell-cell adhesion in breast cancer patients, while higher TβRIII expression is a strong predictor of overall survival in breast cancer patients. These data support a novel, clinically relevant role for TβRIII in regulating integrin α5 localization, reveal a novel crosstalk mechanism between the integrin and TGF-β superfamily signaling pathways and identify β-arrestin2 as a regulator of α5β1 trafficking. © 2013 Macmillan Publishers Limited. All rights reserved.

Authors
Mythreye, K; Knelson, EH; Gatza, CE; Gatza, ML; Blobe, GC
MLA Citation
Mythreye, K, Knelson, EH, Gatza, CE, Gatza, ML, and Blobe, GC. "TβRIII/β-arrestin2 regulates integrin α5β1 trafficking, function, and localization in epithelial cells." Oncogene 32.11 (2013): 1416-1427.
Source
scival
Published In
Oncogene: Including Oncogene Reviews
Volume
32
Issue
11
Publish Date
2013
Start Page
1416
End Page
1427
DOI
10.1038/onc.2012.157

The type III TGFβ receptor regulates filopodia formation via a Cdc42-mediated IRSp53-N-WASP interaction in epithelial cells

Cell adhesion and migration are tightly controlled by regulated changes in the actin cytoskeleton. Previously we reported that the TGFβ (transforming growth factor β) superfamily co-receptor, TβRIII (type III TGFβ receptor; also known as betaglycan), regulates cell adhesion, migration and invasion, and suppresses cancer progression, in part, through activation of the smallGTPase Cdc42 (cell division cycle 42), and Cdc42-dependent alterations to the actin cytoskeleton. In the present study we demonstrate that TβRIII specifically promotes filopodial formation and extension in MCF10A and HMEC (human mammary epithelial cell) mammary epithelial cells. Mechanistically, cell-surface TβRIII and Cdc42 co-localize to filopodial structures and co-complex in a β-Arrestin2-dependent, and a TβRI/TβRII- independent manner. The β-Arrestin2-mediated interaction between TβRIII and Cdc42 increases complex formation between theCdc42 effectors IRSp53 with N-WASP (neuronal Wiskott-Aldrich syndrome protein) to increase filopodial formation. We demonstrate a function link between filopodial structures and epithelial cell adhesion as regulated by the TβRIII-Cdc42 interaction. The present studies identify TβRIII as a novel regulator of IRSp53/N-WASP via Cdc42 to regulate filopodial formation and cell adhesion. © 2013 Biochemical Society.

Authors
Oh, SY; Knelson, EH; Blobe, GC; Mythreye, K
MLA Citation
Oh, SY, Knelson, EH, Blobe, GC, and Mythreye, K. "The type III TGFβ receptor regulates filopodia formation via a Cdc42-mediated IRSp53-N-WASP interaction in epithelial cells." Biochemical Journal 454.1 (2013): 79-89.
PMID
23750457
Source
scival
Published In
The Biochemical journal
Volume
454
Issue
1
Publish Date
2013
Start Page
79
End Page
89
DOI
10.1042/BJ20121701

Endoglin mediates fibronectin/α5β1 integrin and TGF-β pathway crosstalk in endothelial cells.

Both the transforming growth factor β (TGF-β) and integrin signalling pathways have well-established roles in angiogenesis. However, how these pathways integrate to regulate angiogenesis is unknown. Here, we show that the extracellular matrix component, fibronectin, and its cellular receptor, α5β1 integrin, specifically increase TGF-β1- and BMP-9-induced Smad1/5/8 phosphorylation via the TGF-β superfamily receptors endoglin and activin-like kinase-1 (ALK1). Fibronectin and α5β1 integrin increase Smad1/5/8 signalling by promoting endoglin/ALK1 cell surface complex formation. In a reciprocal manner, TGF-β1 activates α5β1 integrin and downstream signalling to focal adhesion kinase (FAK) in an endoglin-dependent manner. α5β1 integrin and endoglin form a complex on the cell surface and co-internalize, with their internalization regulating α5β1 integrin activation and signalling. Functionally, endoglin-mediated fibronectin/α5β1 integrin and TGF-β pathway crosstalk alter the responses of endothelial cells to TGF-β1, switching TGF-β1 from a promoter to a suppressor of migration, inhibiting TGF-β1-mediated apoptosis to promote capillary stability, and partially mediating developmental angiogenesis in vivo. These studies provide a novel mechanism for the regulation of TGF-β superfamily signalling and endothelial function through crosstalk with integrin signalling pathways.

Authors
Tian, H; Mythreye, K; Golzio, C; Katsanis, N; Blobe, GC
MLA Citation
Tian, H, Mythreye, K, Golzio, C, Katsanis, N, and Blobe, GC. "Endoglin mediates fibronectin/α5β1 integrin and TGF-β pathway crosstalk in endothelial cells." EMBO J 31.19 (October 3, 2012): 3885-3900.
PMID
22940691
Source
pubmed
Published In
EMBO Journal
Volume
31
Issue
19
Publish Date
2012
Start Page
3885
End Page
3900
DOI
10.1038/emboj.2012.246

Endoglin regulates PI3-kinase/Akt trafficking and signaling to alter endothelial capillary stability during angiogenesis.

Endoglin (CD105) is an endothelial-specific transforming growth factor β (TGF-β) coreceptor essential for angiogenesis and vascular homeostasis. Although endoglin dysfunction contributes to numerous vascular conditions, the mechanism of endoglin action remains poorly understood. Here we report a novel mechanism in which endoglin and Gα-interacting protein C-terminus-interacting protein (GIPC)-mediated trafficking of phosphatidylinositol 3-kinase (PI3K) regulates endothelial signaling and function. We demonstrate that endoglin interacts with the PI3K subunits p110α and p85 via GIPC to recruit and activate PI3K and Akt at the cell membrane. Opposing ligand-induced effects are observed in which TGF-β1 attenuates, whereas bone morphogenetic protein-9 enhances, endoglin/GIPC-mediated membrane scaffolding of PI3K and Akt to alter endothelial capillary tube stability in vitro. Moreover, we employ the first transgenic zebrafish model for endoglin to demonstrate that GIPC is a critical component of endoglin function during developmental angiogenesis in vivo. These studies define a novel non-Smad function for endoglin and GIPC in regulating endothelial cell function during angiogenesis.

Authors
Lee, NY; Golzio, C; Gatza, CE; Sharma, A; Katsanis, N; Blobe, GC
MLA Citation
Lee, NY, Golzio, C, Gatza, CE, Sharma, A, Katsanis, N, and Blobe, GC. "Endoglin regulates PI3-kinase/Akt trafficking and signaling to alter endothelial capillary stability during angiogenesis." Mol Biol Cell 23.13 (July 2012): 2412-2423.
PMID
22593212
Source
pubmed
Published In
Molecular Biology of the Cell
Volume
23
Issue
13
Publish Date
2012
Start Page
2412
End Page
2423
DOI
10.1091/mbc.E11-12-0993

A phase I study of bevacizumab, everolimus and panitumumab in advanced solid tumors.

PURPOSE: Preclinical data suggest concurrent inhibition of VEGF, mTOR and EGFR pathways may augment antitumor and antiangiogenic effects compared to inhibition of each pathway alone. This study evaluated the maximum tolerated dose/recommended phase II dose and safety and tolerability of bevacizumab, everolimus and panitumumab drug combination. METHODS: Subjects with advanced solid tumors received escalating doses of everolimus and flat dosing of panitumumab at 4.8 mg/kg and bevacizumab at 10 mg/kg every 2 weeks. Dose-limiting toxicities (DLTs) were assessed in cycle 1; toxicity evaluation was closely monitored throughout treatment. Treatment continued until disease progression or undesirable toxicity. RESULTS: Thirty-two subjects were evaluable for toxicity; 31 subjects were evaluable for tumor response. DLTs were observed in cohorts with everolimus at 10 and 5 mg daily and included grade 3 mucositis, skin rash and thrombocytopenia. Therefore, everolimus was dose-reduced to 5 mg three times weekly, which improved the tolerability of the treatment regimen. Common adverse events were skin rash/pruritus (91 %), mucositis/stomatitis (75 %), hypomagnesemia (72 %), hypocalcemia (56 %) and hypokalemia (50 %). There were 3 partial responses; an additional 10 subjects had stable disease ≥6 months. Three subjects with ovarian cancer and one with endometrial cancer achieved prolonged disease control ranging from 11 to >40 months. CONCLUSIONS: The recommended phase II dose is everolimus at 5 mg three times weekly plus panitumumab at 4.8 mg/kg and bevacizumab at 10 mg/kg every 2 weeks. This dosing regimen has an acceptable safety and tolerability profile and appears to have moderate the clinical activity in refractory tumors.

Authors
Vlahovic, G; Meadows, KL; Uronis, HE; Morse, MA; Blobe, GC; Riedel, RF; Zafar, SY; Alvarez-Secord, A; Gockerman, J; Starodub, AN; Ready, NE; Anderson, EL; Bendell, JC; Hurwitz, HI
MLA Citation
Vlahovic, G, Meadows, KL, Uronis, HE, Morse, MA, Blobe, GC, Riedel, RF, Zafar, SY, Alvarez-Secord, A, Gockerman, J, Starodub, AN, Ready, NE, Anderson, EL, Bendell, JC, and Hurwitz, HI. "A phase I study of bevacizumab, everolimus and panitumumab in advanced solid tumors." Cancer Chemother Pharmacol 70.1 (July 2012): 95-102.
PMID
22638798
Source
pubmed
Published In
Cancer Chemotherapy and Pharmacology
Volume
70
Issue
1
Publish Date
2012
Start Page
95
End Page
102
DOI
10.1007/s00280-012-1889-8

Effect of the loss of the type III TGF beta receptor during tumor progression on tumor microenvironment: Preclinical development of TGF beta inhibition and TGF beta-related biomarkers to enhance immunotherapy efficacy.

Authors
Hanks, BA; Holtzhausen, A; Gimpel, P; Jamieson, R; Campbell, OM; Sun, L; Augustine, CK; Tyler, DS; Osada, T; Morse, M; Ling, LE; Lyerly, HK; Blobe, GC
MLA Citation
Hanks, BA, Holtzhausen, A, Gimpel, P, Jamieson, R, Campbell, OM, Sun, L, Augustine, CK, Tyler, DS, Osada, T, Morse, M, Ling, LE, Lyerly, HK, and Blobe, GC. "Effect of the loss of the type III TGF beta receptor during tumor progression on tumor microenvironment: Preclinical development of TGF beta inhibition and TGF beta-related biomarkers to enhance immunotherapy efficacy." May 20, 2012.
Source
wos-lite
Published In
Journal of Clinical Oncology
Volume
30
Issue
15
Publish Date
2012

Effect of the vaccine Ad5 [E1-, E2b-]-CEA(6D) on CEA-directed CMI responses in patients with advanced CEA-expressing malignancies in a phase I/II clinical trial

Authors
Morse, M; Hobeika, A; Chaudhry, A; Amalfitano, A; Niedzwiecki, D; Clay, TM; Osada, T; Devi, G; Burnett, BK; Weinhold, K; Hsu, SD; Blobe, GC; Xu, Y; Nguyen, S; Dua, R; Balcaitis, S; Gabitzsch, E; Balint, J; Jones, F; Lyerly, HK
MLA Citation
Morse, M, Hobeika, A, Chaudhry, A, Amalfitano, A, Niedzwiecki, D, Clay, TM, Osada, T, Devi, G, Burnett, BK, Weinhold, K, Hsu, SD, Blobe, GC, Xu, Y, Nguyen, S, Dua, R, Balcaitis, S, Gabitzsch, E, Balint, J, Jones, F, and Lyerly, HK. "Effect of the vaccine Ad5 [E1-, E2b-]-CEA(6D) on CEA-directed CMI responses in patients with advanced CEA-expressing malignancies in a phase I/II clinical trial." May 20, 2012.
Source
wos-lite
Published In
Journal of Clinical Oncology
Volume
30
Issue
15
Publish Date
2012

Abstract 3035: Bone morphogenetic proteins signal through Smad2 and Smad3 to regulate cell migration and proliferation

Authors
Holtzhausen, A; How, T; Gersh, BC; Blobe, GC
MLA Citation
Holtzhausen, A, How, T, Gersh, BC, and Blobe, GC. "Abstract 3035: Bone morphogenetic proteins signal through Smad2 and Smad3 to regulate cell migration and proliferation." Cancer Research 72.8 Supplement (April 15, 2012): 3035-3035.
Source
crossref
Published In
Cancer Research
Volume
72
Issue
8 Supplement
Publish Date
2012
Start Page
3035
End Page
3035
DOI
10.1158/1538-7445.AM2012-3035

Endocardial cell epithelial-mesenchymal transformation requires Type III TGFβ receptor interaction with GIPC.

An early event in heart valve formation is the epithelial-mesenchymal transformation (EMT) of a subpopulation of endothelial cells in specific regions of the heart tube, the endocardial cushions. The Type III TGFβ receptor (TGFβR3) is required for TGFβ2- or BMP-2-stimulated EMT in atrioventricular endocardial cushion (AVC) explants in vitro but the mediators downstream of TGFβR3 are not well described. Using AVC and ventricular explants as an in vitro assay, we found an absolute requirement for specific TGFβR3 cytoplasmic residues, GAIP-interacting protein, C terminus (GIPC), and specific Activin Receptor-Like Kinases (ALK)s for TGFβR3-mediated EMT when stimulated by TGFβ2 or BMP-2. The introduction of TGFβR3 into nontransforming ventricular endocardial cells, followed by the addition of either TGFβ2 or BMP-2, results in EMT. TGFβR3 lacking the entire cytoplasmic domain, or only the 3C-terminal amino acids that are required to bind GIPC, fails to support EMT in response to TGFβ2 or BMP-2. Overexpression of GIPC in AVC endocardial cells enhanced EMT while siRNA-mediated silencing of GIPC in ventricular cells overexpressing TGFβR3 significantly inhibited EMT. Targeting of specific ALKs by siRNA revealed that TGFβR3-mediated EMT requires ALK2 and ALK3, in addition to ALK5, but not ALK4 or ALK6. Taken together, these data identify GIPC, ALK2, ALK3, and ALK5 as signaling components required for TGFβR3-mediated endothelial cell EMT.

Authors
Townsend, TA; Robinson, JY; How, T; DeLaughter, DM; Blobe, GC; Barnett, JV
MLA Citation
Townsend, TA, Robinson, JY, How, T, DeLaughter, DM, Blobe, GC, and Barnett, JV. "Endocardial cell epithelial-mesenchymal transformation requires Type III TGFβ receptor interaction with GIPC." Cell Signal 24.1 (January 2012): 247-256.
PMID
21945156
Source
pubmed
Published In
Cellular Signalling
Volume
24
Issue
1
Publish Date
2012
Start Page
247
End Page
256
DOI
10.1016/j.cellsig.2011.09.006

Molecular characterization of the tumor-suppressive function of nischarin in breast cancer.

BACKGROUND: Nischarin (encoded by NISCH), an α5 integrin-binding protein, has been identified as a regulator of breast cancer cell invasion. We hypothesized that it might be a tumor suppressor and were interested in its regulation. METHODS: We examined nischarin expression in approximately 300 human breast cancer and normal tissues using quantitative polymerase chain reaction and immunohistochemistry. Loss of heterozygosity analysis was performed by examining three microsatellite markers located near the NISCH locus in normal and tumor tissues. We generated derivatives of MDA-MB-231 human metastatic breast cancer cells that overexpressed nischarin and measured tumor growth from these cells as xenografts in mice; metastasis by these cells after tail vein injection; and α5 integrin expression, Rac, and focal adhesion kinase (FAK) signaling using western blotting. We also generated clones of MCF-7 human breast cancer cells in which nischarin expression was silenced and measured tumor growth in mouse xenograft models (n = 5 for all mouse experiments). P values were from two-sided Student t tests in pairwise comparisons. RESULTS: Normal human breast tissue samples had statistically significantly higher expression of nischarin mRNA compared with tumor tissue samples (mean level in normal breast = 50.7 [arbitrary units], in breast tumor = 16.49 [arbitrary units], difference = 34.21, 95% confidence interval [CI] = 11.63 to 56.79, P = .003), and loss of heterozygosity was associated with loss of nischarin expression. MDA-MB-231 cells in which nischarin was overexpressed had statistically significantly reduced tumor growth and metastasis compared with parental MDA-MB-231 cells (mean volume at day 40, control vs nischarin-expressing tumors, 1977 vs 42.27 mm(3), difference = 1935 mm(3), 95% CI = 395 to 3475 mm(3), P = .025). Moreover, MCF-7 tumor xenografts in which nischarin expression was silenced grew statistically significantly faster than parental cells (mean volume at day 63, tumors with scrambled short hairpin RNA [shRNA] vs with nischarin shRNA, 224 vs 1262 mm(3), difference = 1038 mm(3), 95% CI = 899.6 to 1176 mm(3), P < .001). Overexpression of nischarin was associated with decreased α5 integrin expression, FAK phosphorylation, and Rac activation. CONCLUSION: Nischarin may be a novel tumor suppressor that limits breast cancer progression by regulating α5 integrin expression and subsequently α5 integrin-, FAK-, and Rac-mediated signaling.

Authors
Baranwal, S; Wang, Y; Rathinam, R; Lee, J; Jin, L; McGoey, R; Pylayeva, Y; Giancotti, F; Blobe, GC; Alahari, SK
MLA Citation
Baranwal, S, Wang, Y, Rathinam, R, Lee, J, Jin, L, McGoey, R, Pylayeva, Y, Giancotti, F, Blobe, GC, and Alahari, SK. "Molecular characterization of the tumor-suppressive function of nischarin in breast cancer." J Natl Cancer Inst 103.20 (October 19, 2011): 1513-1528.
PMID
21917605
Source
pubmed
Published In
Journal of the National Cancer Institute
Volume
103
Issue
20
Publish Date
2011
Start Page
1513
End Page
1528
DOI
10.1093/jnci/djr350

A phase II study of oxaliplatin, dose-intense capecitabine, and high-dose bevacizumab in the treatment of metastatic colorectal cancer.

BACKGROUND: This study was designed to determine the efficacy and tolerability of a novel 2-week regimen of capecitabine, oxaliplatin (OHP), and bevacizumab in patients with chemo-naive advanced colorectal cancer. PATIENTS AND METHODS: Nineteen patients with previously untreated advanced colorectal cancer received capecitabine at 1000 mg/m(2) twice a day on days 1-5 and days 8-12 of a 14-day cycle, and OHP at 85 mg/m(2) and bevacizumab at 10 mg/kg every 2 weeks. Because of unacceptable toxicities, the capecitabine dose was reduced to 850 mg/m(2). Thirty-one additional patients were treated at the lower capecitabine dose. Treatment continued until disease progression, persistent intolerable toxicity, or physician and/or patient discretion. RESULTS: Overall, toxicities were better managed and tolerated at the 850 mg/-m(2) capecitabine dose. The most common treatment-related grade ≥ 3 toxicities were diarrhea and sensory neuropathy. In the first 19 subjects, the response rate was 63% (95% confidence interval [CI], 38%-84%) and 5 patients had stable disease; median progression-free survival (PFS) was 10.1 months (95% CI, 5.7-19.5 months). In the subsequent 31 patients, the response was 42% (95% CI, 25%-61%); 11 patients had stable disease and median PFS was 10.4 months (95% CI, 6.9-15.4); median overall survival was 24.8 months (95% CI, 12.9-39.7). CONCLUSIONS: This novel regimen of capecitabine at 850 mg/m(2) twice a day on days 1-5 and days 8-12 and OHP at 85 mg/m(2)and bevacizumab at 10 mg/kg every 14 days is clinically active in advanced colorectal cancer. The toxicity profile of this regimen is consistent with the standard every-3-week dosing schedule.

Authors
Wong, NS; Fernando, NH; Bendell, JC; Morse, MA; Blobe, GC; Honeycutt, W; Pang, H; Hurwitz, HI
MLA Citation
Wong, NS, Fernando, NH, Bendell, JC, Morse, MA, Blobe, GC, Honeycutt, W, Pang, H, and Hurwitz, HI. "A phase II study of oxaliplatin, dose-intense capecitabine, and high-dose bevacizumab in the treatment of metastatic colorectal cancer." Clin Colorectal Cancer 10.3 (September 2011): 210-216.
PMID
21855046
Source
pubmed
Published In
Clinical colorectal cancer
Volume
10
Issue
3
Publish Date
2011
Start Page
210
End Page
216
DOI
10.1016/j.clcc.2011.03.018

Mechanical stiffness grades metastatic potential in patient tumor cells and in cancer cell lines.

Cancer cells are defined by their ability to invade through the basement membrane, a critical step during metastasis. While increased secretion of proteases, which facilitates degradation of the basement membrane, and alterations in the cytoskeletal architecture of cancer cells have been previously studied, the contribution of the mechanical properties of cells in invasion is unclear. Here, we applied a magnetic tweezer system to establish that stiffness of patient tumor cells and cancer cell lines inversely correlates with migration and invasion through three-dimensional basement membranes, a correlation known as a power law. We found that cancer cells with the highest migratory and invasive potential are five times less stiff than cells with the lowest migration and invasion potential. Moreover, decreasing cell stiffness by pharmacologic inhibition of myosin II increases invasiveness, whereas increasing cell stiffness by restoring expression of the metastasis suppressor TβRIII/betaglycan decreases invasiveness. These findings are the first demonstration of the power-law relation between the stiffness and the invasiveness of cancer cells and show that mechanical phenotypes can be used to grade the metastatic potential of cell populations with the potential for single cell grading. The measurement of a mechanical phenotype, taking minutes rather than hours needed for invasion assays, is promising as a quantitative diagnostic method and as a discovery tool for therapeutics. By showing that altering stiffness predictably alters invasiveness, our results indicate that pathways regulating these mechanical phenotypes are novel targets for molecular therapy of cancer.

Authors
Swaminathan, V; Mythreye, K; O'Brien, ET; Berchuck, A; Blobe, GC; Superfine, R
MLA Citation
Swaminathan, V, Mythreye, K, O'Brien, ET, Berchuck, A, Blobe, GC, and Superfine, R. "Mechanical stiffness grades metastatic potential in patient tumor cells and in cancer cell lines." Cancer Res 71.15 (August 1, 2011): 5075-5080.
PMID
21642375
Source
pubmed
Published In
Cancer Research
Volume
71
Issue
15
Publish Date
2011
Start Page
5075
End Page
5080
DOI
10.1158/0008-5472.CAN-11-0247

Type III TGF-β receptor enhances colon cancer cell migration and anchorage-independent growth.

The type III TGF-β receptor (TβRIII or betagylcan) is a TGF-β superfamily coreceptor with emerging roles in regulating TGF-β superfamily signaling and cancer progression. Alterations in TGF-β superfamily signaling are common in colon cancer; however, the role of TβRIII has not been examined. Although TβRIII expression is frequently lost at the message and protein level in human cancers and suppresses cancer progression in these contexts, here we demonstrate that, in colon cancer, TβRIII messenger RNA expression is not significantly altered and TβRIII expression is more frequently increased at the protein level, suggesting a distinct role for TβRIII in colon cancer. Increasing TβRIII expression in colon cancer model systems enhanced ligand-mediated phosphorylation of p38 and the Smad proteins, while switching TGF-β and BMP-2 from inhibitors to stimulators of colon cancer cell proliferation, inhibiting ligand-induced p21 and p27 expression. In addition, increasing TβRIII expression increased ligand-stimulated anchorage-independent growth, a resistance to ligand- and chemotherapy-induced apoptosis, cell migration and modestly increased tumorigenicity in vivo. In a reciprocal manner, silencing endogenous TβRIII expression decreased colon cancer cell migration. These data support a model whereby TβRIII mediates TGF-β superfamily ligand-induced colon cancer progression and support a context-dependent role for TβRIII in regulating cancer progression.

Authors
Gatza, CE; Holtzhausen, A; Kirkbride, KC; Morton, A; Gatza, ML; Datto, MB; Blobe, GC
MLA Citation
Gatza, CE, Holtzhausen, A, Kirkbride, KC, Morton, A, Gatza, ML, Datto, MB, and Blobe, GC. "Type III TGF-β receptor enhances colon cancer cell migration and anchorage-independent growth." Neoplasia 13.8 (August 2011): 758-770.
PMID
21847367
Source
pubmed
Published In
Neoplasia (New York, N.Y.)
Volume
13
Issue
8
Publish Date
2011
Start Page
758
End Page
770

Phase I study of dasatinib in combination with capecitabine, oxaliplatin, and bevacizumab followed by an expanded cohort in previously untreated metastatic colorectal cancer

Authors
Strickler, JH; Cohn, AL; Arrowood, C; Haley, S; Morse, M; Uronis, H; Blobe, GC; Hsu, SD; Zafar, Y; Hurwitz, H
MLA Citation
Strickler, JH, Cohn, AL, Arrowood, C, Haley, S, Morse, M, Uronis, H, Blobe, GC, Hsu, SD, Zafar, Y, and Hurwitz, H. "Phase I study of dasatinib in combination with capecitabine, oxaliplatin, and bevacizumab followed by an expanded cohort in previously untreated metastatic colorectal cancer." JOURNAL OF CLINICAL ONCOLOGY 29.15 (May 20, 2011).
Source
wos-lite
Published In
Journal of Clinical Oncology
Volume
29
Issue
15
Publish Date
2011

Phase I study of dasatinib in combination with capecitabine, oxaliplatin, and bevacizumab followed by an expanded cohort in previously untreated metastatic colorectal cancer.

3586 Background: SRC is a non-receptor tyrosine kinase involved in normal and tumor cell signaling functions including cell proliferation, angiogenesis and survival. Dasatinib (D) is a potent inhibitor of SRC kinase activity. Preclinical data suggests the addition of D to standard chemotherapy agents for colon cancer may increase anti-tumor activity. We evaluated D in combination with capecitabine (C), oxaliplatin (O) and bevacizumab (B) in a phase I dose escalation study followed by an expanded cohort in first-line colorectal.For dose escalation, eligible patients had advanced solid tumors with adequate organ function and no increased risk for class-related toxicities. B and O were given intravenously, and C and D were orally administered; cycle length was 21 days. C was dosed at 850 mg/m2 on days 1-14; O was dosed at 130 mg/m2 and B was dosed at 7.5 mg/kg on day one of each cycle. D was dosed at 50 mg twice daily in cohort one and 70 mg once daily in cohort -1. Dose limiting toxicity (DLT) was assessed in cycle 1.Dose escalation is complete with 10 subjects evaluable for DLT toxicity and 11 subjects evaluable for efficacy. Two DLTs were observed out of 4 evaluable subjects in cohort one. Six evaluable subjects were enrolled in the -1 cohort with 1 DLT. Two subjects have been enrolled in the expanded cohort. Possible grade ≥3 treatment-related adverse events (AEs) included neutropenia, febrile neutropenia, anorexia, diarrhea, fatigue, anemia, dehydration and grade 5 GI-perforation. One non-treatment related death was due to disease progression. D-related nausea, anorexia and fatigue were responsive to low dose oral steroids; fluid retention was responsive to diuretics. Of 13 subjects evaluable for efficacy, 3 subjects had a partial response (PR), 6 had stable disease (SD) as best response.D in combination with C, O and B is well-tolerated with a toxicity profile similar to standard C, O and B.The recommended phase II dose is C at 850 mg/m2 on days 1-14, O at 130 mg/m2 and B at 7.5 mg/kg on day one of each cycle, and D at 70 mg once daily. Enrollment in the expanded cohort of first-line colorectal is nearing completion.

Authors
Strickler, JH; Cohn, AL; Arrowood, C; Haley, S; Morse, M; Uronis, H; Blobe, GC; Hsu, SD; Zafar, Y; Hurwitz, H
MLA Citation
Strickler, JH, Cohn, AL, Arrowood, C, Haley, S, Morse, M, Uronis, H, Blobe, GC, Hsu, SD, Zafar, Y, and Hurwitz, H. "Phase I study of dasatinib in combination with capecitabine, oxaliplatin, and bevacizumab followed by an expanded cohort in previously untreated metastatic colorectal cancer." Journal of clinical oncology : official journal of the American Society of Clinical Oncology 29.15_suppl (May 2011): 3586-.
PMID
28020244
Source
epmc
Published In
Journal of Clinical Oncology
Volume
29
Issue
15_suppl
Publish Date
2011
Start Page
3586

Role of the type III TGF-β receptor in modulating antitumor immunity during breast cancer progression.

10540 Background: We have shown that breast cancers downregulate the expression of the type III TGF-β receptor (TβRIII) tumor suppressor during tumor progression. Previous work has shown TβRIII to undergo ectodomain shedding, enabling the sequestration of the soluble TGF-β ligand and the inhibition of the TGF-β signaling pathway.  The TGF-β cytokine inhibits dendritic cell (DC)-dependent antigen presentation.  We hypothesize that the downregulation of TβRIII during breast tumor development permits enhanced TGF-β signaling within the local DCs of the tumor microenvironment allowing the tumor to evade the host immune response.Our data suggest that the tumor suppressor properties of TβRIII in the 4T1 murine metastatic breast cancer model are diminished in immunosuppressed hosts. Indeed, loss of TβRIII allows for the progression of more immunogenic Her2/neu-expressing 4T1 tumors and suppresses Her2/neu-specific T cell responses. Flow cytometry and rt-PCR studies indicate that breast tumors which lack TβRIII expression exhibit reduced numbers of infiltrating CD8+ T cells and increased regulatoy T cells (Tregs), findings which are supported by human microarray data. In addition, DCs within TβRIIIlo tumors and their draining lymph nodes (TDLNs) express enhanced levels of the indoleamine 2,3-dioxygenase (IDO) enzyme as well as the CCL22 chemokine, which correlates with expanded local Treg populations. Studies have shown 4T1-RIII conditioned media to inhibit TGF-β signaling within DCs and to suppress the TGF-β-mediated inhibition of DC maturation. Our work is showing that DCs within the TDLNs of TβRIIIhi tumors exhibit a more mature phenotype.The increased TGF-β signaling capacity of DCs residing in TβRIIIlo tumors may allow for increased local CCL22 expression; thereby promoting Treg recruitment and allowing for CTLA-4-mediated IDO upregulation by local DCs.This pathway represents a novel mechanism for evading the host anti-tumor immune response, supports the targeting of TGF-β as a strategy to enhance the efficacy of immunotherapeutic approaches for solid tumors, and suggests that serum levels of soluble TβRIII may represent a useful biomarker for immunotherapy.

Authors
Hanks, BA; Campbell, OM; Lee, JD; Morse, M; Clay, TM; Lyerly, HK; Blobe, GC
MLA Citation
Hanks, BA, Campbell, OM, Lee, JD, Morse, M, Clay, TM, Lyerly, HK, and Blobe, GC. "Role of the type III TGF-β receptor in modulating antitumor immunity during breast cancer progression." Journal of clinical oncology : official journal of the American Society of Clinical Oncology 29.15_suppl (May 2011): 10540-.
PMID
28021827
Source
epmc
Published In
Journal of Clinical Oncology
Volume
29
Issue
15_suppl
Publish Date
2011
Start Page
10540

The type III transforming growth factor-β receptor inhibits proliferation, migration, and adhesion in human myeloma cells.

Transforming growth factor-β (TGF-β) plays an important role in regulating hematopoiesis, inhibiting proliferation while stimulating differentiation when appropriate. We previously demonstrated that the type III TGF-β receptor (TβRIII, or betaglycan) serves as a novel suppressor of cancer progression in epithelial tumors; however, its role in hematologic malignancies is unknown. Here we demonstrate that TβRIII protein expression is decreased or lost in the majority of human multiple myeloma specimens. Functionally, restoring TβRIII expression in myeloma cells significantly inhibited cell growth, proliferation, and motility, largely independent of its ligand presentation role. In a reciprocal fashion, shRNA-mediated silencing of endogenous TβRIII expression enhanced cell growth, proliferation, and motility. Although apoptosis was not affected, TβRIII inhibited proliferation through induction of the cyclin-dependent kinase inhibitors p21 and p27. TβRIII further regulated myeloma cell adhesion, increasing homotypic myeloma cell adhesion while decreasing myeloma heterotropic adhesion to bone marrow stromal cells. Mechanistically, live cell imaging of myeloma and stroma cell cocultures revealed that TβRIII-mediated inhibition of heterotropic adhesion was associated with decreased duration of myeloma/bone marrow stromal cell interaction. These results suggest that loss of TβRIII expression during multiple myeloma progression contributes to disease progression through its functional effects on increased cell growth, proliferation, motility, and adhesion.

Authors
Lambert, KE; Huang, H; Mythreye, K; Blobe, GC
MLA Citation
Lambert, KE, Huang, H, Mythreye, K, and Blobe, GC. "The type III transforming growth factor-β receptor inhibits proliferation, migration, and adhesion in human myeloma cells." Mol Biol Cell 22.9 (May 2011): 1463-1472.
PMID
21411633
Source
pubmed
Published In
Molecular Biology of the Cell
Volume
22
Issue
9
Publish Date
2011
Start Page
1463
End Page
1472
DOI
10.1091/mbc.E10-11-0877

Phase I study of dasatinib in combination with capecitabine, oxaliplatin, and bevacizumab followed by an expanded cohort in previously untreated metastatic colorectal cancer.

513 Background: SRC is a non-receptor tyrosine kinase involved in normal and tumor cell signaling functions including cell proliferation, angiogenesis and survival. Dasatinib (D) is a potent inhibitor of SRC kinase activity. Preclinical data suggests the addition of D to standard chemotherapy agents for colon cancer may increase anti-tumor activity. We evaluated D in combination with capecitabine (C), oxaliplatin (O) and bevacizumab (B) in a phase I dose escalation study followed by an expanded cohort in 1st line colorectal.For dose escalation, eligible patients had advanced solid tumors with adequate organ and bone marrow function and no increased risk for class-related toxicities. B and O were given intravenously, and C and D were orally administered; cycle length was 21 days. C was dosed at 850 mg/m2 on days 1-14; O was dosed at 130 mg/m2 and B was dosed at 7.5 mg/kg on day one of each cycle. D was dosed at 50 mg twice daily in cohort one and 70 mg once daily in cohort -1. Dose limiting toxicity (DLT) was assessed in cycle 1.Dose escalation is complete with 10 subjects evaluable for toxicity and 11 subjects evaluable for efficacy. Two DLTs were observed out of 5 evaluable subjects in cohort one. Six evaluable subjects were enrolled in the -1 cohort with 1 DLT. Possible grade ≥ 3 treatment-related adverse events (AEs) included neutropenia, febrile neutropenia, anorexia, diarrhea, fatigue, anemia, hypophosphatemia, hyponatremia and grade 5 GI-perforation. One non-treatment related death was due to disease progression. D-related nausea and fatigue were responsive to low dose oral steroids; fluid retention was responsive to diuretics. Of 10 subjects evaluable for efficacy, 1 subject had a partial response (PR), 2 had a minor response (MR), and 4 had stable disease (SD). Four subjects had disease control (PR, MR, or SD) ≥ 6 months.D in combination with C, O and B is well-tolerated with a toxicity profile similar to standard C, O and B.The recommended phase II dose is C at 850 mg/m2 on days 1-14, O at 130 mg/m2 and B at 7.5 mg/kg on day one of each cycle, and D at 70 mg once daily. Enrollment in the expanded cohort of 1st line colorectal is ongoing. [Table: see text].

Authors
Starodub, A; Cohn, AL; Arrowood, C; Haley, S; Morse, M; Uronis, HE; Blobe, GC; Hsu, SD; Zafar, Y; Hurwitz, H
MLA Citation
Starodub, A, Cohn, AL, Arrowood, C, Haley, S, Morse, M, Uronis, HE, Blobe, GC, Hsu, SD, Zafar, Y, and Hurwitz, H. "Phase I study of dasatinib in combination with capecitabine, oxaliplatin, and bevacizumab followed by an expanded cohort in previously untreated metastatic colorectal cancer." Journal of clinical oncology : official journal of the American Society of Clinical Oncology 29.4_suppl (February 2011): 513-.
PMID
27985744
Source
epmc
Published In
Journal of Clinical Oncology
Volume
29
Issue
4_suppl
Publish Date
2011
Start Page
513

A phase I study of bevacizumab (B) in combination with everolimus (E) and erlotinib (E) in advanced cancer (BEE).

PURPOSE: VEGF, mTOR, and EGFR inhibitors have demonstrated anti-tumor and anti-angiogenic effects alone and in combination with each other. This study evaluated the safety, tolerability, and pharmacokinetics of bevacizumab, everolimus, and erlotinib combination. METHODS: Doublet therapy consisted of bevacizumab at 10 mg/kg every 14 days and everolimus 5 mg daily which escalated to 10 mg daily. Erlotinib 75 mg daily was added to the phase II dose recommended phase II dose (RPTD) of bevacizumab and everolimus. Dose-limiting toxicity (DLT) was assessed in cycle 1. RESULTS: Forty-eight patients with advanced solid malignancies were evaluable for DLT and efficacy. No DLTs were observed in the doublet dose escalation. Two DLTs (grade 3 mucositis and grade 3 rash) were observed with the addition of erlotinib 75 mg daily. Consequently, triplet doses were adjusted and were better tolerated. Four patients had a partial response. Median progression-free survival (PFS) for the doublet therapy was 6.0 months (0.5 to 32+ months) and 5.5 months (0.8 to 27+ months) for the triplet therapy. Systemic exposure of everolimus was significantly higher in combination with erlotinib (476 ± 161 ng h/mL) compared to when given alone (393 ± 156 ng h/mL; P = 0.020). CONCLUSIONS: The RPTD for the doublet therapy is bevacizumab 10 mg/kg every 14 days and everolimus 10 mg daily, and the RPTD for the triplet therapy is bevacizumab 5 mg/kg every 14 days, everolimus 5 mg and erlotinib 75 mg daily. Prolonged disease stability was demonstrated in tumors known to respond to mTOR inhibition and potentially resistant to VEGF blockade.

Authors
Bullock, KE; Petros, WP; Younis, I; Uronis, HE; Morse, MA; Blobe, GC; Zafar, SY; Gockerman, JP; Lager, JJ; Truax, R; Meadows, KL; Howard, LA; O'Neill, MM; Broadwater, G; Hurwitz, HI; Bendell, JC
MLA Citation
Bullock, KE, Petros, WP, Younis, I, Uronis, HE, Morse, MA, Blobe, GC, Zafar, SY, Gockerman, JP, Lager, JJ, Truax, R, Meadows, KL, Howard, LA, O'Neill, MM, Broadwater, G, Hurwitz, HI, and Bendell, JC. "A phase I study of bevacizumab (B) in combination with everolimus (E) and erlotinib (E) in advanced cancer (BEE)." Cancer Chemother Pharmacol 67.2 (February 2011): 465-474.
PMID
21079958
Source
pubmed
Published In
Cancer Chemotherapy and Pharmacology
Volume
67
Issue
2
Publish Date
2011
Start Page
465
End Page
474
DOI
10.1007/s00280-010-1507-6

A phase II study of capecitabine, oxaliplatin, bevacizumab and cetuximab in the treatment of metastatic colorectal cancer.

AIM: This study was designed to determine the efficacy and tolerability of capecitabine, oxaliplatin and bevacizumab in combination with cetuximab as first-line therapy for advanced colorectal cancer. PATIENTS AND METHODS: Patients with previously untreated advanced colorectal cancer received oxaliplatin 130 mg/m² and bevacizumab 7.5 mg/kg every three weeks, capecitabine 850 mg/m² twice daily on days 1-14, and cetuximab at 400 mg/m² load and 250 mg/m² weekly. KRAS, BRAF and PI3K mutation status from paraffin-embedded tumor samples were assessed using real-time polymerase chain reaction. RESULTS: Thirty patients were evaluable for safety and efficacy. One patient had a complete response and 12 patients had a partial response, giving an overall response rate of 43% (95% confidence interval (CI) 25%-63%). Fifteen patients had stable disease. The median time to progression was 10.3 months (95% CI, 6.8-16.3 months). The median overall survival was 18.8 months (95% CI, 14.2-23.7 months). Common grade ≥ 3 non-hematological toxicities were skin rash (37%), sensory neuropathy (27%) and diarrhea (17%). Grade ≥ 3 hematological toxicities were uncommon. Mutations in KRAS, BRAF and PI3K occurred in 34.5%, 10.3% and 10.3% of patients respectively, but did not correlate with treatment outcome. CONCLUSION: The addition of cetuximab to capecitabine, oxaliplatin and bevacizumab did not improve the three-drug regimen activity compared to published data and was associated with significant toxicities requiring frequent dose modifications. KRAS, BRAF, and PI3K mutation status were consistent with published literature, but did not affect outcome in this small study.

Authors
Wong, NS; Fernando, NH; Nixon, AB; Cushman, S; Aklilu, M; Bendell, JC; Morse, MA; Blobe, GC; Ashton, J; Pang, H; Hurwitz, HI
MLA Citation
Wong, NS, Fernando, NH, Nixon, AB, Cushman, S, Aklilu, M, Bendell, JC, Morse, MA, Blobe, GC, Ashton, J, Pang, H, and Hurwitz, HI. "A phase II study of capecitabine, oxaliplatin, bevacizumab and cetuximab in the treatment of metastatic colorectal cancer." Anticancer Res 31.1 (January 2011): 255-261.
PMID
21273607
Source
pubmed
Published In
Anticancer research
Volume
31
Issue
1
Publish Date
2011
Start Page
255
End Page
261

BMP-2 and TGFβ2 shared pathways regulate endocardial cell transformation.

Valvular heart disease is a major cause of mortality and morbidity. Revealing the cellular processes and molecules that regulate valve formation and remodeling is required to develop effective therapies. A key step in valve formation during heart development is the epithelial-mesenchymal transformation (EMT) of a subpopulation of endocardial cells in the atrioventricular cushion (AVC). The type III transforming growth factor-β receptor (TGFβR3) regulates AVC endocardial cell EMT in vitro and mesenchymal cell differentiation in vivo. Little is known concerning the signaling mechanisms downstream of TGFβR3. Here we use endocardial cell EMT in vitro to determine the role of 2 well-characterized downstream TGFβ signaling pathways in TGFβR3-dependent endocardial cell EMT. Targeting of Smad4, the common mediator Smad, demonstrated that Smad signaling is required for EMT in the AVC and TGFβR3-dependent EMT stimulated by TGFβ2 or BMP-2. Although we show that Smads 1, 2, 3, and 5 are required for AVC EMT, overexpression of Smad1 or Smad3 is not sufficient to induce EMT. Consistent with the activation of the Par6/Smurf1 pathway downstream of TGFβR3, targeting ALK5, Par6, or Smurf1 significantly inhibited EMT in response to either TGFβ2 or BMP-2. The requirement for ALK5 activity, Par6, and Smurf1 for TGFβR3-dependent endocardial cell EMT is consistent with the documented role of this pathway in the dissolution of tight junctions. Taken together, our data demonstrate that TGFβR3-dependent endocardial cell EMT stimulated by either TGFβ2 or BMP-2 requires Smad4 and the activation of the Par6/Smurf1 pathway.

Authors
Townsend, TA; Robinson, JY; Deig, CR; Hill, CR; Misfeldt, A; Blobe, GC; Barnett, JV
MLA Citation
Townsend, TA, Robinson, JY, Deig, CR, Hill, CR, Misfeldt, A, Blobe, GC, and Barnett, JV. "BMP-2 and TGFβ2 shared pathways regulate endocardial cell transformation." Cells Tissues Organs 194.1 (2011): 1-12.
PMID
21212630
Source
pubmed
Published In
Cells, tissues, organs
Volume
194
Issue
1
Publish Date
2011
Start Page
1
End Page
12
DOI
10.1159/000322035

A phase II trial of bevacizumab plus everolimus for patients with refractory metastatic colorectal cancer.

PURPOSE: For patients with metastatic colorectal cancer (mCRC), no standard therapy exists after progression on 5-fluorouracil, oxaliplatin, irinotecan, bevacizumab, and cetuximab or panitumumab. Preclinical data demonstrated that combined vascular endothelial growth factor and mammalian target of rapamycin inhibition has greater antiangiogenic and antitumor activity than either monotherapy. A phase I study of bevacizumab plus everolimus demonstrated that the combination is safe; activity was seen in several patients with refractory mCRC. METHODS: Fifty patients with refractory mCRC were enrolled and received bevacizumab at 10 mg/kg every 2 weeks and everolimus at 10 mg orally daily. RESULTS: Of the 50 patients enrolled, the median age was 56 years and the median number of prior regimens was four. Forty-seven patients (96%) had prior bevacizumab exposure and 42 patients (84%) had documented progression on prior bevacizumab-based therapy. Forty-nine patients were evaluable for response; eight patients had minor responses (16%) and an additional 15 patients (30%) had stable disease (SD). No complete or partial responses were seen. The median progression-free survival interval was 2.3 months; however, 26% of patients achieved prolonged SD for ≥6 months, and three patients (6%) were on study for >1 year. The median overall survival duration was 8.1 months. The most common grade 1-2 toxicities were mucositis (68%) and hyperlipidemia (64%). Clinically significant grade ≥3 toxicities included hypertension (14%), fistula/abscess/perforation (8%), mucositis (6%), and hemorrhage (2%). CONCLUSIONS: Bevacizumab plus everolimus is generally tolerable but may have risks related to mucosal damage and/or wound healing. Bevacizumab plus everolimus appears to have modest activity in refractory mCRC in patients.

Authors
Altomare, I; Bendell, JC; Bullock, KE; Uronis, HE; Morse, MA; Hsu, SD; Zafar, SY; Blobe, GC; Pang, H; Honeycutt, W; Sutton, L; Hurwitz, HI
MLA Citation
Altomare, I, Bendell, JC, Bullock, KE, Uronis, HE, Morse, MA, Hsu, SD, Zafar, SY, Blobe, GC, Pang, H, Honeycutt, W, Sutton, L, and Hurwitz, HI. "A phase II trial of bevacizumab plus everolimus for patients with refractory metastatic colorectal cancer." Oncologist 16.8 (2011): 1131-1137.
PMID
21795432
Source
pubmed
Published In
The oncologist
Volume
16
Issue
8
Publish Date
2011
Start Page
1131
End Page
1137
DOI
10.1634/theoncologist.2011-0078

Role of stiffness and force response in integrin mediated signaling and metastasis.

Authors
Swaminathan, V; Mythreye, K; Guilluy, C; O'Brien, E; Blobe, GC; Burridge, K; Superfine, R
MLA Citation
Swaminathan, V, Mythreye, K, Guilluy, C, O'Brien, E, Blobe, GC, Burridge, K, and Superfine, R. "Role of stiffness and force response in integrin mediated signaling and metastasis." 2011.
Source
wos-lite
Published In
Molecular Biology of the Cell
Volume
22
Publish Date
2011

Deep sequencing of the small RNA transcriptome of normal and malignant human B cells identifies hundreds of novel microRNAs.

A role for microRNA (miRNA) has been recognized in nearly every biologic system examined thus far. A complete delineation of their role must be preceded by the identification of all miRNAs present in any system. We elucidated the complete small RNA transcriptome of normal and malignant B cells through deep sequencing of 31 normal and malignant human B-cell samples that comprise the spectrum of B-cell differentiation and common malignant phenotypes. We identified the expression of 333 known miRNAs, which is more than twice the number previously recognized in any tissue type. We further identified the expression of 286 candidate novel miRNAs in normal and malignant B cells. These miRNAs were validated at a high rate (92%) using quantitative polymerase chain reaction, and we demonstrated their application in the distinction of clinically relevant subgroups of lymphoma. We further demonstrated that a novel miRNA cluster, previously annotated as a hypothetical gene LOC100130622, contains 6 novel miRNAs that regulate the transforming growth factor-β pathway. Thus, our work suggests that more than a third of the miRNAs present in most cellular types are currently unknown and that these miRNAs may regulate important cellular functions.

Authors
Jima, DD; Zhang, J; Jacobs, C; Richards, KL; Dunphy, CH; Choi, WWL; Au, WY; Srivastava, G; Czader, MB; Rizzieri, DA; Lagoo, AS; Lugar, PL; Mann, KP; Flowers, CR; Bernal-Mizrachi, L; Naresh, KN; Evens, AM; Gordon, LI; Luftig, M; Friedman, DR; Weinberg, JB; Thompson, MA; Gill, JI; Liu, Q; How, T; Grubor, V; Gao, Y; Patel, A; Wu, H; Zhu, J; Blobe, GC; Lipsky, PE; Chadburn, A; Dave, SS; Hematologic Malignancies Research Consortium,
MLA Citation
Jima, DD, Zhang, J, Jacobs, C, Richards, KL, Dunphy, CH, Choi, WWL, Au, WY, Srivastava, G, Czader, MB, Rizzieri, DA, Lagoo, AS, Lugar, PL, Mann, KP, Flowers, CR, Bernal-Mizrachi, L, Naresh, KN, Evens, AM, Gordon, LI, Luftig, M, Friedman, DR, Weinberg, JB, Thompson, MA, Gill, JI, Liu, Q, How, T, Grubor, V, Gao, Y, Patel, A, Wu, H, Zhu, J, Blobe, GC, Lipsky, PE, Chadburn, A, Dave, SS, and Hematologic Malignancies Research Consortium, . "Deep sequencing of the small RNA transcriptome of normal and malignant human B cells identifies hundreds of novel microRNAs." Blood 116.23 (December 2, 2010): e118-e127.
PMID
20733160
Source
pubmed
Published In
Blood
Volume
116
Issue
23
Publish Date
2010
Start Page
e118
End Page
e127
DOI
10.1182/blood-2010-05-285403

Roles for the type III TGF-beta receptor in human cancer.

Transforming growth factor beta (TGF-beta) superfamily ligands have important roles in regulating cellular homeostasis, embryonic development, differentiation, proliferation, immune surveillance, angiogenesis, motility, and apoptosis in a cell type and context specific manner. TGF-beta superfamily signaling pathways also have diverse roles in human cancer, functioning to either suppress or promote cancer progression. The TGF-beta superfamily co-receptor, the type III TGF-beta receptor (TbetaRIII, also known as betaglycan) mediates TGF-beta superfamily ligand dependent as well as ligand independent signaling to both Smad and non-Smad signaling pathways. Loss of TbetaRIII expression during cancer progression and direct effects of TbetaRIII on regulating cell migration, invasion, proliferation, and angiogenesis support a role for TbetaRIII as a suppressor of cancer progression and/or as a metastasis suppressor. Defining the physiological function and mechanism of TbetaRIII action and alterations in TbetaRIII function during cancer progression should enable more effective targeting of TbetaRIII and TbetaRIII mediated functions for the diagnosis and treatment of human cancer.

Authors
Gatza, CE; Oh, SY; Blobe, GC
MLA Citation
Gatza, CE, Oh, SY, and Blobe, GC. "Roles for the type III TGF-beta receptor in human cancer." Cell Signal 22.8 (August 2010): 1163-1174. (Review)
PMID
20153821
Source
pubmed
Published In
Cellular Signalling
Volume
22
Issue
8
Publish Date
2010
Start Page
1163
End Page
1174
DOI
10.1016/j.cellsig.2010.01.016

Loss of type III transforming growth factor-beta receptor expression is due to methylation silencing of the transcription factor GATA3 in renal cell carcinoma.

Loss of transforming growth factor-beta receptor III (TbetaRIII) correlates with loss of transforming growth factor-beta (TGF-beta) responsiveness and suggests a role for dysregulated TGF-beta signaling in clear cell renal cell carcinoma (ccRCC) progression and metastasis. Here we identify that for all stages of ccRCC TbetaRIII expression is downregulated in patient-matched tissue samples and cell lines. We find that this loss of expression is not due to methylation of the gene and we define GATA3 as the first transcriptional factor to positively regulate TbetaRIII expression in human cells. We localize GATA3's binding to a 10-bp region of the TbetaRIII proximal promoter. We demonstrate that GATA3 mRNA is downregulated in all stages, of ccRCC, mechanistically show that GATA3 is methylated in ccRCC patient tumor tissues as well as cell lines, and that inhibiting GATA3 expression in normal renal epithelial cells downregulates TbetaRIII mRNA and protein expression. These data support a sequential model whereby loss of GATA3 expression through epigenetic silencing decreases TbetaRIII expression during ccRCC progression.

Authors
Cooper, SJ; Zou, H; Legrand, SN; Marlow, LA; von Roemeling, CA; Radisky, DC; Wu, KJ; Hempel, N; Margulis, V; Tun, HW; Blobe, GC; Wood, CG; Copland, JA
MLA Citation
Cooper, SJ, Zou, H, Legrand, SN, Marlow, LA, von Roemeling, CA, Radisky, DC, Wu, KJ, Hempel, N, Margulis, V, Tun, HW, Blobe, GC, Wood, CG, and Copland, JA. "Loss of type III transforming growth factor-beta receptor expression is due to methylation silencing of the transcription factor GATA3 in renal cell carcinoma." Oncogene 29.20 (May 20, 2010): 2905-2915.
PMID
20208565
Source
pubmed
Published In
Oncogene: Including Oncogene Reviews
Volume
29
Issue
20
Publish Date
2010
Start Page
2905
End Page
2915
DOI
10.1038/onc.2010.64

Abstract 3971: The type III tgf-β receptor mediates bmp signaling in normal and cancerous mammary epithelial cells

Authors
Gatza, CE; Blobe, GC
MLA Citation
Gatza, CE, and Blobe, GC. "Abstract 3971: The type III tgf-β receptor mediates bmp signaling in normal and cancerous mammary epithelial cells." Cancer Research 70.8 Supplement (April 15, 2010): 3971-3971.
Source
crossref
Published In
Cancer Research
Volume
70
Issue
8 Supplement
Publish Date
2010
Start Page
3971
End Page
3971
DOI
10.1158/1538-7445.AM10-3971

Gfi-1B controls human erythroid and megakaryocytic differentiation by regulating TGF-beta signaling at the bipotent erythro-megakaryocytic progenitor stage.

Growth factor independence-1B (Gfi-1B) is a transcriptional repressor essential for erythropoiesis and megakaryopoiesis. Targeted gene disruption of GFI1B in mice leads to embryonic lethality resulting from failure to produce definitive erythrocytes, hindering the study of Gfi-1B function in adult hematopoiesis. We here show that, in humans, Gfi-1B controls the development of erythrocytes and megakaryocytes by regulating the proliferation and differentiation of bipotent erythro-megakaryocytic progenitors. We further identify in this cell population the type III transforming growth factor-beta receptor gene, TGFBR3, as a direct target of Gfi-1B. Knockdown of Gfi-1B results in altered transforming growth factor-beta (TGF-beta) signaling as shown by the increase in Smad2 phosphorylation and its inability to associate to the transcription intermediary factor 1-gamma (TIF1-gamma). Because the Smad2/TIF1-gamma complex is known to specifically regulate erythroid differentiation, we propose that, by repressing TGF-beta type III receptor (TbetaRIotaII) expression, Gfi-1B favors the Smad2/TIF1-gamma interaction downstream of TGF-beta signaling, allowing immature progenitors to differentiate toward the erythroid lineage.

Authors
Randrianarison-Huetz, V; Laurent, B; Bardet, V; Blobe, GC; Huetz, F; Duménil, D
MLA Citation
Randrianarison-Huetz, V, Laurent, B, Bardet, V, Blobe, GC, Huetz, F, and Duménil, D. "Gfi-1B controls human erythroid and megakaryocytic differentiation by regulating TGF-beta signaling at the bipotent erythro-megakaryocytic progenitor stage." Blood 115.14 (April 8, 2010): 2784-2795.
PMID
20124515
Source
pubmed
Published In
Blood
Volume
115
Issue
14
Publish Date
2010
Start Page
2784
End Page
2795
DOI
10.1182/blood-2009-09-241752

A phase I dose-escalation study of imatinib mesylate (Gleevec/STI571) plus capecitabine (Xeloda) in advanced solid tumors.

UNLABELLED: The aim of this study was to determine the maximally tolerated dose, recommended phase II dose and toxicity profile of capecitabine plus imatinib mesylate combination. PATIENTS AND METHODS: Twenty-four patients with advanced solid tumors were treated with capecitabine twice daily on days 1-14 and imatinib mesylate once daily on a 21-day cycle. Dose-limiting toxicity was assessed during the first cycle. Treatment continued until disease progression or undesirable toxicity. RESULTS: Six patients were treated with capecitabine at 1000 mg/m(2) and imatinib mesylate 300 mg; unacceptable toxicity due to grade 2 intolerable hand-foot syndrome and/or grade > or = 2 diarrhea was observed. Doses were subsequently reduced to capecitabine at 750 mg/m(2) and imatinib mesylate at 300 mg; toxicities were better tolerated at the lower dose. Dose-limiting toxicities consisted of grade 3 diarrhea, anorexia and fatigue lasting > or = 4 days. Treatment-related adverse events greater than or equal to grade 3 included anemia, diarrhea, dysuria, hypophosphatemia and vertigo. Minor responses were observed in two patients: stable disease > or = 6 months was observed in two out of twenty-one evaluable patients. CONCLUSION: Full doses of capecitabine and imatinib mesylate were not tolerable. The maximum tolerated dose and the recommended phase II dose for this drug combination is capecitabine at 750 mg/m(2) twice daily for 1-14 days and imatinib at 300 mg once daily on a 21-day cycle.

Authors
Dugan, E; Truax, R; Meadows, KL; Nixon, AB; Petros, WP; Favaro, J; Fernando, NH; Morse, MA; Blobe, GC; Hurwitz, HI
MLA Citation
Dugan, E, Truax, R, Meadows, KL, Nixon, AB, Petros, WP, Favaro, J, Fernando, NH, Morse, MA, Blobe, GC, and Hurwitz, HI. "A phase I dose-escalation study of imatinib mesylate (Gleevec/STI571) plus capecitabine (Xeloda) in advanced solid tumors." Anticancer Res 30.4 (April 2010): 1251-1256.
PMID
20530436
Source
pubmed
Published In
Anticancer research
Volume
30
Issue
4
Publish Date
2010
Start Page
1251
End Page
1256

ALK5 phosphorylation of the endoglin cytoplasmic domain regulates Smad1/5/8 signaling and endothelial cell migration.

Endoglin, an endothelial cell-specific transforming growth factor-beta (TGF-beta) superfamily coreceptor, has an essential role in angiogenesis. Endoglin-null mice have an embryonic lethal phenotype due to defects in angiogenesis and mutations in endoglin result in the vascular disease hereditary hemorrhagic telangiectasia type I. Increased endoglin expression in the proliferating endothelium of tumors has been correlated with metastasis, tumor grade and decreased survival. Although endoglin is thought to regulate TGF-beta superfamily signaling in endothelial cells through regulating the balance between two TGF-beta-responsive pathways, the activin receptor-like kinase 5 (ALK5)/Smad2/3 pathway and the activin receptor-like kinase 1 (ALK1)/Smad1/5/8 pathway, the mechanism by which endoglin regulates angiogenesis has not been defined. Here, we investigate the role of the cytoplasmic domain of endoglin and its phosphorylation by ALK5 in regulating endoglin function in endothelial cells. We demonstrate that the cytoplasmic domain of endoglin is basally phosphorylated by ALK5, primarily on serines 646 and 649, in endothelial cells. Functionally, the loss of phosphorylation at serine 646 resulted in a loss of endoglin-mediated inhibition of Smad1/5/8 signaling in response to TGF-beta and endothelial cell migration, whereas loss of phosphorylation at both serines 646 and 649 resulted in a loss of endoglin-mediated inhibition of Smad1/5/8 signaling in response to bone morphogenetic protein-9. Taken together, these results support endoglin phosphorylation by ALK5 as an important mechanism for regulating TGF-beta superfamily signaling and migration in endothelial cells.

Authors
Ray, BN; Lee, NY; How, T; Blobe, GC
MLA Citation
Ray, BN, Lee, NY, How, T, and Blobe, GC. "ALK5 phosphorylation of the endoglin cytoplasmic domain regulates Smad1/5/8 signaling and endothelial cell migration." Carcinogenesis 31.3 (March 2010): 435-441.
PMID
20042635
Source
pubmed
Published In
Carcinogenesis
Volume
31
Issue
3
Publish Date
2010
Start Page
435
End Page
441
DOI
10.1093/carcin/bgp327

The type III TGF-beta receptor suppresses breast cancer progression through GIPC-mediated inhibition of TGF-beta signaling.

Loss of expression of the type III transforming growth factor-beta receptor (TbetaRIII or betaglycan), a transforming growth factor-beta (TGF-beta) superfamily co-receptor, is common in human breast cancers. TbetaRIII suppresses cancer progression in vivo by reducing cancer cell migration and invasion by largely unknown mechanisms. Here, we demonstrate that the cytoplasmic domain of TbetaRIII is essential for TbetaRIII-mediated downregulation of migration and invasion in vitro and TbetaRIII-mediated inhibition of breast cancer progression in vivo. Functionally, the cytoplasmic domain of TbetaRIII is required to attenuate TGF-beta signaling, whereas TbetaRIII-mediated attenuation of TGF-beta signaling is required for TbetaRIII-mediated inhibition of migration and invasion. Mechanistically, both TbetaRIII-mediated inhibition of TGF-beta signaling and TbetaRIII-mediated inhibition of invasion occur through the interaction of the cytoplasmic domain of TbetaRIII with the scaffolding protein GAIP-interacting protein C-terminus (GIPC). Taken together, these studies support a functional role for the TbetaRIII cytoplasmic domain interacting with GIPC to suppress breast cancer progression.

Authors
Lee, JD; Hempel, N; Lee, NY; Blobe, GC
MLA Citation
Lee, JD, Hempel, N, Lee, NY, and Blobe, GC. "The type III TGF-beta receptor suppresses breast cancer progression through GIPC-mediated inhibition of TGF-beta signaling." Carcinogenesis 31.2 (February 2010): 175-183.
PMID
19955393
Source
pubmed
Published In
Carcinogenesis
Volume
31
Issue
2
Publish Date
2010
Start Page
175
End Page
183
DOI
10.1093/carcin/bgp271

Phase I dose escalation study of gemcitabine plus irinotecan in advanced solid tumors.

AIM: To determine the maximally tolerated dose (MTD), recommended phase II dose (RPTD) and toxicity profile of gemcitabine plus irinotecan combination. PATIENTS AND METHODS: Thirty-nine evaluable patients with advanced solid tumors were treated with gemcitabine (Gem) and irinotecan (Iri) on days 1, 8 and 15 of a 28-day cycle. Dose levels included Gem/Iri 700/50, 900/50, 900/75, 500/50 mg/m(2) respectively. Dose-limiting toxicity (DLT) was assessed during cycle one; toxicity evaluation was closely monitored throughout the course of treatment. Treatment continued until disease progression or unacceptable toxicity. RESULTS: DLTs primarily consisted of grade > or = 3 thrombocytopenia lasting > or = 4 days often accompanied by grade > or = 3 neutropenia. Other grade > or = 3 toxicities included vomiting, diarrhea, fatigue and elevated alkaline phosphatase. Three patients had a partial response. Stable disease as best response was seen in 16 patients, ranging from 2-18 months. CONCLUSION: The MTD/RPTD is gemcitabine 500 mg/m(2) plus irinotecan 50 mg/m(2) on days 1, 8 and 15 of a 28-day cycle. Given the toxicity profile and negative results of phase III studies, no further testing of this treatment combination is recommended.

Authors
Dugan, E; Truax, R; Meadows, KL; Blobe, GC; Morse, MA; Fernando, NH; Gockerman, JP; Petros, WP; Hurwitz, HI
MLA Citation
Dugan, E, Truax, R, Meadows, KL, Blobe, GC, Morse, MA, Fernando, NH, Gockerman, JP, Petros, WP, and Hurwitz, HI. "Phase I dose escalation study of gemcitabine plus irinotecan in advanced solid tumors." Anticancer Res 29.12 (December 2009): 5149-5153.
PMID
20044630
Source
pubmed
Published In
Anticancer research
Volume
29
Issue
12
Publish Date
2009
Start Page
5149
End Page
5153

Casein kinase 2beta as a novel enhancer of activin-like receptor-1 signaling.

ALK-1 is a transforming growth factor beta (TGF-beta) superfamily receptor that is predominantly expressed in endothelial cells and is essential for angiogenesis, as demonstrated by the embryonic lethal phentoype when targeted for deletion in mice and its mutation in the human disease hereditary hemorrhagic telangiectasia. Although ALK-1 and the endothelial-specific TGF-beta superfamily coreceptor, endoglin, form a heteromeric complex and bind similar TGF-beta superfamily ligands, their signaling mechanisms remain poorly characterized. Here we report the identification of CK2beta, the regulatory subunit of protein kinase CK2, as a novel enhancer of ALK-1 signaling. The cytoplasmic domain of ALK-1 specifically binds to CK2beta in vitro and in vivo. NAAIRS mutagenesis studies define amino acid sequences 181-199 of CK2beta and 207-212 of ALK-1 as the interaction domains, respectively. The ALK-1/CK2beta interaction specifically enhanced Smad1/5/8 phosphorylation and ALK-1-mediated reporter activation in response to TGF-beta1 and BMP-9 treatment. In a reciprocal manner, siRNA-mediated silencing of endogenous CK2beta inhibited TGF-beta1 and BMP-9-stimulated Smad1/5/8 phosphorylation and ALK-1-mediated reporter activation. Functionally, CK2beta enhanced the ability of activated or ligand-stimulated ALK-1 to inhibit endothelial cell migration. Similarly, ALK-1 and CK2beta antagonized endothelial tubule formation in Matrigel. These studies support CK2beta as an important regulator of ALK-1 signaling and ALK-1-mediated functions in endothelial cells.

Authors
Lee, NY; Haney, JC; Sogani, J; Blobe, GC
MLA Citation
Lee, NY, Haney, JC, Sogani, J, and Blobe, GC. "Casein kinase 2beta as a novel enhancer of activin-like receptor-1 signaling." FASEB J 23.11 (November 2009): 3712-3721.
PMID
19592636
Source
pubmed
Published In
The FASEB journal : official publication of the Federation of American Societies for Experimental Biology
Volume
23
Issue
11
Publish Date
2009
Start Page
3712
End Page
3721
DOI
10.1096/fj.09-131607

Proteoglycan signaling co-receptors: roles in cell adhesion, migration and invasion.

Signaling co-receptors are diverse, multifunctional components of most major signaling pathways, with roles in mediating and regulating signaling in both physiological and pathophysiological circumstances. Many of these signaling co-receptors, including CD44, glypicans, neuropilins, syndecans and TssRIII/betaglycan are also proteoglycans. Like other co-receptors, these proteoglycan signaling co-receptors can bind multiple ligands, promoting the formation of receptor signaling complexes and regulating signaling at the cell surface. The proteoglycan signaling co-receptors can also function as structural molecules to regulate adhesion, cell migration, morphogenesis and differentiation. Through a balance of these signaling and structural roles, proteoglycan signaling co-receptors can have either tumor promoting or tumor suppressing functions. Defining the role and mechanism of action of these proteoglycan signaling co-receptors should enable more effective targeting of these co-receptors and their respective pathways for the treatment of human disease.

Authors
Mythreye, K; Blobe, GC
MLA Citation
Mythreye, K, and Blobe, GC. "Proteoglycan signaling co-receptors: roles in cell adhesion, migration and invasion." Cell Signal 21.11 (November 2009): 1548-1558. (Review)
PMID
19427900
Source
pubmed
Published In
Cellular Signalling
Volume
21
Issue
11
Publish Date
2009
Start Page
1548
End Page
1558
DOI
10.1016/j.cellsig.2009.05.001

The type III TGFbeta receptor regulates directional migration: new tricks for an old dog.

The type III transforming growth factor beta (TGFbeta) receptor (T beta RIII or betaglycan) is a TGFbeta superfamily co-receptor. Loss of T beta RIII expression occurs in a broad spectrum of human cancers including cancers of the breast, kidney, lung, ovary, pancreas and prostate. T beta RIII suppresses cancer progression, in part, by reducing cancer cell motility. This T beta RIII function is independent of its TGFbeta signaling role, with T beta RIII activating Cdc42 via its interaction with the scaffolding protein beta-arrestin2 to re-organize the actin cytoskeleton, decrease directional persistence and inhibit random migration in both epithelial-derived cancer cells and normal epithelial cells. These studies contribute to a growing body of literature supporting essential and non-redundant roles for T beta RIII and emphasize the importance of continued investigation of T beta RIII and other signaling co-receptors.

Authors
Mythreye, K; Blobe, GC
MLA Citation
Mythreye, K, and Blobe, GC. "The type III TGFbeta receptor regulates directional migration: new tricks for an old dog." Cell Cycle 8.19 (October 1, 2009): 3069-3070.
PMID
19755845
Source
pubmed
Published In
Cell Cycle
Volume
8
Issue
19
Publish Date
2009
Start Page
3069
End Page
3070
DOI
10.4161/cc.8.19.9419

The transforming growth factor-beta type III receptor mediates distinct subcellular trafficking and downstream signaling of activin-like kinase (ALK)3 and ALK6 receptors.

Bone morphogenetic proteins (BMPs) signal through the BMP type I and type II receptors to regulate cellular processes, including embryonic development. The type I BMP receptors activin-like kinase (ALK)3 and ALK6 share a high degree of homology, yet possess distinct signaling roles. Here, we report that although the transforming growth factor (TGF)-beta type III receptor (TbetaRIII) enhanced both ALK3 and ALK6 signaling, TbetaRIII more potently enhanced ALK6-mediated stimulation of the BMP-responsive promoters XVent2 and 3GC2, and up-regulation of the early response gene Smad6. In contrast, TbetaRIII specifically enhanced ALK3-mediated up-regulation of the early response gene ID-1. TbetaRIII associated with ALK3 primarily through their extracellular domains, whereas its interaction with ALK6 required both the extracellular and cytoplasmic domains. TbetaRIII, along with its interacting scaffolding protein beta-arrestin2, induced the internalization of ALK6. In contrast, TbetaRIII colocalized with and resulted in the cell surface retention of ALK3, independently of beta-arrestin2. Although complex formation between TbetaRIII, ALK6, and beta-arrestin2 and TbetaRIII/ALK6 internalization resulted in maximal BMP signaling, the TbetaRIII mutant unable to interact with beta-arrestin2, TbetaRIII-T841A, was unable to do so. These studies support a novel role for TbetaRIII in mediating differential ALK3 and ALK6 subcellular trafficking resulting in distinct signaling downstream of ALK3 and ALK6.

Authors
Lee, NY; Kirkbride, KC; Sheu, RD; Blobe, GC
MLA Citation
Lee, NY, Kirkbride, KC, Sheu, RD, and Blobe, GC. "The transforming growth factor-beta type III receptor mediates distinct subcellular trafficking and downstream signaling of activin-like kinase (ALK)3 and ALK6 receptors." Mol Biol Cell 20.20 (October 2009): 4362-4370.
PMID
19726563
Source
pubmed
Published In
Molecular Biology of the Cell
Volume
20
Issue
20
Publish Date
2009
Start Page
4362
End Page
4370
DOI
10.1091/mbc.E09-07-0539

The type III transforming growth factor-beta receptor negatively regulates nuclear factor kappa B signaling through its interaction with beta-arrestin2.

Transforming growth factor-beta (TGF-beta) increases or decreases nuclear factor kappa B (NFkappaB) signaling in a context-dependent manner through mechanisms that remain to be defined. The type III transforming growth factor-beta receptor (TbetaRIII) is a TGF-beta superfamily co-receptor with emerging roles in both mediating and regulating TGF-beta superfamily signaling. We have previously reported a novel interaction of TbetaRIII with the scaffolding protein, beta-arrestin2, which results in TbetaRIII internalization and downregulation of TGF-beta signaling. beta-arrestin2 also scaffolds interacting receptors with the mitogen-activated protein kinase and NFkappaB-signaling pathways. Here, we demonstrate that TbetaRIII, through its interaction with beta-arrestin2, negatively regulates NFkappaB signaling in MCF10A breast epithelial and MDA-MB-231 breast cancer cells. Increasing TbetaRIII expression reduced NFkappaB-mediated transcriptional activation and IkappaBalpha degradation, whereas a TbetaRIII mutant unable to interact with beta-arrestin2, TbetaRIII-T841A, had no effect. In a reciprocal manner, short hairpin RNA-mediated silencing of either TbetaRIII expression or beta-arrestin2 expression increased NFkappaB-mediated transcriptional activation and IkappaBalpha degradation. Functionally, TbetaRIII-mediated repression of NFkappaB signaling is important for TbetaRIII-mediated inhibition of breast cancer cell migration. These studies define a mechanism through which TbetaRIII regulates NFkappaB signaling and expand the roles of this TGF-beta superfamily co-receptor in regulating epithelial cell homeostasis.

Authors
You, HJ; How, T; Blobe, GC
MLA Citation
You, HJ, How, T, and Blobe, GC. "The type III transforming growth factor-beta receptor negatively regulates nuclear factor kappa B signaling through its interaction with beta-arrestin2." Carcinogenesis 30.8 (August 2009): 1281-1287.
PMID
19325136
Source
pubmed
Published In
Carcinogenesis
Volume
30
Issue
8
Publish Date
2009
Start Page
1281
End Page
1287
DOI
10.1093/carcin/bgp071

Bevacizumab (B) plus everolimus (E) in refractory metastatic colorectal cancer (mCRC)

Authors
Bullock, KE; Hurwitz, HI; Uronis, HE; Morse, MA; Blobe, GC; Hsu, SD; Zafar, SY; Nixon, AB; Howard, LA; Bendell, JC
MLA Citation
Bullock, KE, Hurwitz, HI, Uronis, HE, Morse, MA, Blobe, GC, Hsu, SD, Zafar, SY, Nixon, AB, Howard, LA, and Bendell, JC. "Bevacizumab (B) plus everolimus (E) in refractory metastatic colorectal cancer (mCRC)." May 20, 2009.
Source
wos-lite
Published In
Journal of Clinical Oncology
Volume
27
Issue
15
Publish Date
2009

Bevacizumab (B) plus everolimus (E) and panitumumab (P) in refractory advanced solid tumors

Authors
Howard, LA; Bullock, KE; Bendell, JC; Uronis, HE; Vlahovic, G; Blobe, GC; Riedel, RF; Nixon, AB; Gockerman, JP; Hurwitz, HI
MLA Citation
Howard, LA, Bullock, KE, Bendell, JC, Uronis, HE, Vlahovic, G, Blobe, GC, Riedel, RF, Nixon, AB, Gockerman, JP, and Hurwitz, HI. "Bevacizumab (B) plus everolimus (E) and panitumumab (P) in refractory advanced solid tumors." May 20, 2009.
Source
wos-lite
Published In
Journal of Clinical Oncology
Volume
27
Issue
15
Publish Date
2009

The type III TGF-beta receptor regulates epithelial and cancer cell migration through beta-arrestin2-mediated activation of Cdc42.

Loss of expression of the TGF-beta superfamily coreceptor, the type III TGF-beta receptor (TbetaRIII or betaglycan), occurs in a broad spectrum of human cancers including breast, lung, ovarian, pancreatic, prostate, and renal cell cancer. TbetaRIII suppresses cancer progression in vivo, at least in part, by reducing cancer cell motility. However, the mechanism by which TbetaRIII regulates migration is unknown. Here, we demonstrate an unexpected TGF-beta signaling independent role for TbetaRIII in activating Cdc42, altering the actin cytoskeleton and reducing directional persistence to inhibit random migration of both cancer and normal epithelial cells. Functionally, TbetaRIII through its interaction with the scaffolding protein beta-arrestin2, activates Cdc42 and inhibits migration. These studies identify a TGF-beta independent homeostatic function for TbetaRIII in regulating cell migration.

Authors
Mythreye, K; Blobe, GC
MLA Citation
Mythreye, K, and Blobe, GC. "The type III TGF-beta receptor regulates epithelial and cancer cell migration through beta-arrestin2-mediated activation of Cdc42." Proc Natl Acad Sci U S A 106.20 (May 19, 2009): 8221-8226.
PMID
19416857
Source
pubmed
Published In
Proceedings of the National Academy of Sciences of USA
Volume
106
Issue
20
Publish Date
2009
Start Page
8221
End Page
8226
DOI
10.1073/pnas.0812879106

Bevacizumab (B) plus everolimus (E) in refractory metastatic colorectal cancer (mCRC).

4080 Background: For patients (pts) with mCRC, no standard therapy exists after progression on 5-FU, oxaliplatin, irinotecan, bevacizumab, and/or cetuximab/panitumumab. Preclinical data demonstrate combined VEGF and mTOR inhibition has greater anti-angiogenic and anti-tumor activity than either monotherapy. B inhibits VEGF; E inhibits mTOR. Phase I data in patients demonstrated B + E was safe and activity was seen in several pts with refractory mCRC.25 pts with refractory mCRC were enrolled in an expanded cohort of B + E. Doses: B 10 mg/kg q2 wks; E 10 mg PO QD. Blood, skin, and tumor biopsies pre- and on-treatment were collected for markers of response and resistance.At this time, 19 pts (10M: 9F) are evaluable for toxicity; 17 for efficacy. Median age 57 years (range 35-78). Median number prior regimens 3. All pts had prior B exposure; 17 pts had progressive disease on prior B-based therapy. There was one Grade (Gr) 4 adverse event (AE) of hypokalemia. Grade 3 AE related to treatment were bowel perforation/fistula, (n=2), hyperglycemia (3), hypokalemia (3), hypertension (2), fatigue (1), alk phos elevation (1; lab only), hypoalbuminemia (1), and volume depletion (1). Other events of interest were: Gr1-2 mucositis (n=10), Gr1 hyperlipidemia (11). Of 17 pts evaluable for response, 4 pts had SD as best response (median 24 wks, range 17-31+ wks); there were 3 minor responses in pts who had progressed on B (median 16 wks, range 16-27 wks). No CR or PR were seen. Biomarker data is pending.B+E has activity in refractory mCRC in pts who had progressed on a B-based regimen, suggesting B+E may overcome resistance to B. Patient accrual is continuing and updated data will be presented. [Table: see text].

Authors
Bullock, KE; Hurwitz, HI; Uronis, HE; Morse, MA; Blobe, GC; Hsu, SD; Zafar, SY; Nixon, AB; Howard, LA; Bendell, JC
MLA Citation
Bullock, KE, Hurwitz, HI, Uronis, HE, Morse, MA, Blobe, GC, Hsu, SD, Zafar, SY, Nixon, AB, Howard, LA, and Bendell, JC. "Bevacizumab (B) plus everolimus (E) in refractory metastatic colorectal cancer (mCRC)." Journal of clinical oncology : official journal of the American Society of Clinical Oncology 27.15_suppl (May 2009): 4080-.
PMID
27961646
Source
epmc
Published In
Journal of Clinical Oncology
Volume
27
Issue
15_suppl
Publish Date
2009
Start Page
4080

Bevacizumab (B) plus everolimus (E) and panitumumab (P) in refractory advanced solid tumors.

3551 Background: In preclinical models, VEGF, mTOR, and EGFR inhibitors have anti-tumor and anti-angiogenesis effects as monotherapies and in combination. B inhibits VEGF; E inhibits mTOR; P inhibits EGFR. There is also potential for interaction between the pathways. Previously BE and BE + erlotinib were evaluated and showed signs of clinical activity.Patients (pts) with refractory advanced solid tumors were accrued in a phase I dose escalation of B + E + P on a 28d cycle. Dose levels are shown in the table below. DLT was defined as any treatment-related grade 4 heme, grade 3/4 non-heme adverse event (AE), or receiving <85% any study drug in Cycle 1. Blood, skin, and tumor biopsies pre- and on-treatment were collected for correlative biomarkers of angiogenesis.At this time, 12 pts (3M: 9F) are evaluable for toxicity; 9 for efficacy. Median age: 54 years (range 23-72). 9 of 12 pts had prior B exposure. Dose level 1 was expanded due to 1/3 DLT, with total of 3/6 DLT (Grade (Gr) 3 mucositis (n=2), Gr3 hypokalemia (n=1)). Dose level -1 had 3/3 DLT (Gr3, Gr4 mucositis (n=2), Gr3 non-acneform rash (n=1)). Dose level -2 had 0/3 pts DLT. Gr 3-4 related toxicities in cycle 2+: hypokalemia (n=4); hypophosphatemia (n = 1); hypomagnesemia (n = 1); diarrhea (n=1); hoarseness (n=1). Other events of interest were: Gr1-2 mucositis (n=7); Gr1 hyperlipidemia (n=5); Gr1-2 hyperglycemia (n=4); Gr2 hypertension (n=2); Gr1-2 neutropenia (n=5); Gr1-2 thrombocytopenia (n=5). 8/9 evaluable pts had SD as best response (median 26 wks, range 8+ to 32+ wks): 1 pt with pancreatic cancer and progression on 2 prior EGFR inhibitors had prolonged 32+ wk SD. There was 1 minor response (23.3%) in a pt with bevacizumab-refractory ovarian cancer (32+ wks). No CR or PR were seen.B + E + P at full doses has dose limiting toxicities of rash and mucositis. B 10 mg/kg q2wks + E 5 mg q48h + P 4.8 mg/kg q2wks is the maximum tolerated dose. This dose is currently being expanded in 20 patients with extensive pre- and on-treatment biomarker analyses. Updated clinical and biomarker data will be presented. [Table: see text] [Table: see text].

Authors
Howard, LA; Bullock, KE; Bendell, JC; Uronis, HE; Vlahovic, G; Blobe, GC; Riedel, RF; Nixon, AB; Gockerman, JP; Hurwitz, HI
MLA Citation
Howard, LA, Bullock, KE, Bendell, JC, Uronis, HE, Vlahovic, G, Blobe, GC, Riedel, RF, Nixon, AB, Gockerman, JP, and Hurwitz, HI. "Bevacizumab (B) plus everolimus (E) and panitumumab (P) in refractory advanced solid tumors." Journal of clinical oncology : official journal of the American Society of Clinical Oncology 27.15_suppl (May 2009): 3551-.
PMID
27961368
Source
epmc
Published In
Journal of Clinical Oncology
Volume
27
Issue
15_suppl
Publish Date
2009
Start Page
3551

Bone morphogenetic proteins induce pancreatic cancer cell invasiveness through a Smad1-dependent mechanism that involves matrix metalloproteinase-2.

Bone morphogenetic proteins (BMPs) have an emerging role in human cancers. Here we demonstrate that the BMP-signaling pathway is intact and functional in human pancreatic cancer cells, with several BMP signaling components and transcriptional targets upregulated in human pancreatic cancer specimens compared with normal pancreatic tissue. Functionally, multiple BMP family members, including BMP-2, BMP-4 and BMP-7, induce an epithelial to mesenchymal transition (EMT) in the human pancreatic cancer cell line Panc-1, as demonstrated by morphological alterations and loss of E-cadherin expression. BMP-mediated EMT results in an increase in invasiveness of Panc-1 cells, in part through increased expression and activity of matrix metalloproteinase (MMP)-2, a known mediator of pancreatic cancer cell invasiveness. Accompanying EMT, BMP reduces expression of the transforming growth factor (TGF)-beta superfamily receptor, transforming growth factor-beta type III receptor (TbetaRIII), for which we have previously demonstrated loss of expression during pancreatic cancer progression. Maintaining TbetaRIII expression inhibits BMP-mediated invasion and suppresses Smad1 activation. Further, Smad1 is required for BMP-induced invasiveness and partially responsible for BMP-mediated increases in MMP-2 activity. These data suggest that BMP signaling, through Smad1 induction and upregulation of MMP-2, is an important mediator of pancreatic cancer invasiveness and a potential therapeutic target for treating this deadly disease.

Authors
Gordon, KJ; Kirkbride, KC; How, T; Blobe, GC
MLA Citation
Gordon, KJ, Kirkbride, KC, How, T, and Blobe, GC. "Bone morphogenetic proteins induce pancreatic cancer cell invasiveness through a Smad1-dependent mechanism that involves matrix metalloproteinase-2." Carcinogenesis 30.2 (February 2009): 238-248.
PMID
19056927
Source
pubmed
Published In
Carcinogenesis
Volume
30
Issue
2
Publish Date
2009
Start Page
238
End Page
248
DOI
10.1093/carcin/bgn274

Endocytosis of the type III transforming growth factor-beta (TGF-beta) receptor through the clathrin-independent/lipid raft pathway regulates TGF-beta signaling and receptor down-regulation.

Transforming growth factor-beta (TGF-beta) signals through three highly conserved cell surface receptors, the type III TGF-beta receptor (T beta RIII), the type II TGF-beta receptor (T beta RII), and the type I TGF-beta receptor (T beta RI) to regulate diverse cellular processes including cell proliferation, differentiation, migration, and apoptosis. Although T beta RI and T beta RII undergo ligand-independent endocytosis by both clathrin-mediated endocytosis, resulting in enhanced signaling, and clathrin-independent endocytosis, resulting in receptor degradation, the mechanism and function of T beta RIII endocytosis is poorly understood. T beta RIII is a heparan sulfate proteoglycan with a short cytoplasmic tail that functions as a TGF-beta superfamily co-receptor, contributing to TGF-beta signaling through mechanisms yet to be fully defined. We have reported previously that T beta RIII endocytosis, mediated by a novel interaction with beta arrestin-2, results in decreased TGF-beta signaling. Here we demonstrate that T beta RIII undergoes endocytosis in a ligand and glycosaminoglycan modification-independent and cytoplasmic domain-dependent manner, with the interaction of Thr-841 in the cytoplasmic domain of T beta RIII with beta-arrestin2 enhancing T beta RIII endocytosis. T beta RIII undergoes both clathrin-mediated and clathrin-independent endocytosis. Importantly, inhibition of the clathrin-independent, lipid raft pathway, but not of the clathrin-dependent pathway, results in decreased TGF-beta1 induced Smad2 and p38 phosphorylation, supporting a specific role for clathrin-independent endocytosis of T beta RIII in regulating both Smad-dependent and Smad-independent TGF-beta signaling.

Authors
Finger, EC; Lee, NY; You, H-J; Blobe, GC
MLA Citation
Finger, EC, Lee, NY, You, H-J, and Blobe, GC. "Endocytosis of the type III transforming growth factor-beta (TGF-beta) receptor through the clathrin-independent/lipid raft pathway regulates TGF-beta signaling and receptor down-regulation." J Biol Chem 283.50 (December 12, 2008): 34808-34818.
PMID
18845534
Source
pubmed
Published In
The Journal of biological chemistry
Volume
283
Issue
50
Publish Date
2008
Start Page
34808
End Page
34818
DOI
10.1074/jbc.M804741200

Endoglin promotes transforming growth factor beta-mediated Smad 1/5/8 signaling and inhibits endothelial cell migration through its association with GIPC.

Transforming growth factor beta (TGF-beta) signals through two distinct pathways to regulate endothelial cell proliferation, migration, and angiogenesis, the ALK-1/Smad 1/5/8 and ALK-5/Smad2/3 pathways. Endoglin is a co-receptor predominantly expressed in endothelial cells that participates in TGFbeta-mediated signaling with ALK-1 and ALK-5 and regulates critical aspects of cellular and biological responses. The embryonic lethal phenotype of knock-out mice because of defects in angiogenesis and disease-causing mutations resulting in human vascular diseases both support essential roles for endoglin, ALK-1, and ALK-5 in the vasculature. However, the mechanism by which endoglin mediates TGF-beta signaling through ALK-1 and ALK-5 has remained elusive. Here we describe a novel interaction between endoglin and GIPC, a scaffolding protein known to regulate cell surface receptor expression and trafficking. Co-immunoprecipitation and immunofluorescence confocal studies both demonstrate a specific interaction between endoglin and GIPC in endothelial cells, mediated by a class I PDZ binding motif in the cytoplasmic domain of endoglin. Subcellular distribution studies demonstrate that endoglin recruits GIPC to the plasma membrane and co-localizes with GIPC in a TGFbeta-independent manner, with GIPC-promoting cell surface retention of endoglin. Endoglin specifically enhanced TGF-beta1-induced phosphorylation of Smad 1/5/8, increased a Smad 1/5/8 responsive promoter, and inhibited endothelial cell migration in a manner dependent on the ability of endoglin to interact with GIPC. These studies define a novel mechanism for the regulation of endoglin signaling and function in endothelial cells and demonstrate a new role for GIPC in TGF-beta signaling.

Authors
Lee, NY; Ray, B; How, T; Blobe, GC
MLA Citation
Lee, NY, Ray, B, How, T, and Blobe, GC. "Endoglin promotes transforming growth factor beta-mediated Smad 1/5/8 signaling and inhibits endothelial cell migration through its association with GIPC." J Biol Chem 283.47 (November 21, 2008): 32527-32533.
PMID
18775991
Source
pubmed
Published In
The Journal of biological chemistry
Volume
283
Issue
47
Publish Date
2008
Start Page
32527
End Page
32533
DOI
10.1074/jbc.M803059200

Expression of the type III TGF-beta receptor is negatively regulated by TGF-beta.

The type III transforming growth factor-beta receptor (TbetaRIII or betaglycan) is a ubiquitously expressed transforming growth factor-beta (TGF-beta) superfamily coreceptor with essential roles in embryonic development. Recent studies have defined a role for TbetaRIII in the pathogenesis of human cancers, with frequent loss of TbetaRIII expression at the message and protein level. Mechanisms for the loss of TbetaRIII expression remain to be fully defined. Advanced human cancers often have elevated circulating levels of TGF-beta1. Here, we define a specific role for TGF-beta1 in negatively regulating TbetaRIII at the message level in breast and ovarian cancer models. TGF-beta1 decreased TbetaRIII message and protein levels in ovarian (Ovca420) and breast cancer (MDA-MB-231) cell lines in both a dose- and time-dependent manner. TGF-beta1-mediated TbetaRIII repression is mediated by the type I TGF-beta receptor/Smad2/3 pathway as the activin receptor-like kinase 5 (ALK5) inhibitor, SB431542, abrogated this effect, while the expression of constitutively active ALK5 was sufficient to repress TbetaRIII expression. Mechanistically, TGF-beta1 does not affect TbetaRIII messenger RNA (mRNA) stability, but instead directly regulates the TbetaRIII promoter. We define alternative promoters for the TGFBR3 gene, a distal and proximal promoter. Although both promoters are active, only the proximal promoter was responsive and negatively regulated by TGF-beta1 and constitutively active ALK5. Taken together, these studies define TGF-beta1-mediated downregulation of TbetaRIII mRNA expression through effects on the ALK5/Smad2/3 pathway on the TGFBR3 gene proximal promoter as a potential mechanism for decreased TbetaRIII expression in human cancers.

Authors
Hempel, N; How, T; Cooper, SJ; Green, TR; Dong, M; Copland, JA; Wood, CG; Blobe, GC
MLA Citation
Hempel, N, How, T, Cooper, SJ, Green, TR, Dong, M, Copland, JA, Wood, CG, and Blobe, GC. "Expression of the type III TGF-beta receptor is negatively regulated by TGF-beta." Carcinogenesis 29.5 (May 2008): 905-912.
PMID
18299279
Source
pubmed
Published In
Carcinogenesis
Volume
29
Issue
5
Publish Date
2008
Start Page
905
End Page
912
DOI
10.1093/carcin/bgn049

Role of transforming growth factor-beta superfamily signaling pathways in human disease.

Transforming growth factor beta (TGF-beta) superfamily signaling pathways are ubiquitous and essential regulators of cellular processes including proliferation, differentiation, migration, and survival, as well as physiological processes, including embryonic development, angiogenesis, and wound healing. Alterations in these pathways, including either germ-line or somatic mutations or alterations in the expression of members of these signaling pathways often result in human disease. Appropriate regulation of these pathways is required at all levels, particularly at the ligand level, with either a deficiency or an excess of specific TGF-beta superfamily ligands resulting in human disease. TGF-beta superfamily ligands and members of these TGF-beta superfamily signaling pathways also have emerging roles as diagnostic, prognostic or predictive markers for human disease. Ongoing studies will enable targeting of TGF-beta superfamily signaling pathways for the chemoprevention and treatment of human disease.

Authors
Gordon, KJ; Blobe, GC
MLA Citation
Gordon, KJ, and Blobe, GC. "Role of transforming growth factor-beta superfamily signaling pathways in human disease." Biochim Biophys Acta 1782.4 (April 2008): 197-228. (Review)
PMID
18313409
Source
pubmed
Published In
Biochimica et Biophysica Acta: international journal of biochemistry and biophysics
Volume
1782
Issue
4
Publish Date
2008
Start Page
197
End Page
228
DOI
10.1016/j.bbadis.2008.01.006

Bone morphogenetic proteins signal through the transforming growth factor-beta type III receptor.

The bone morphogenetic protein (BMP) family, the largest subfamily of the structurally conserved transforming growth factor-beta (TGF-beta) superfamily of growth factors, are multifunctional regulators of development, proliferation, and differentiation. The TGF-beta type III receptor (TbetaRIII or betaglycan) is an abundant cell surface proteoglycan that has been well characterized as a TGF-beta and inhibin receptor. Here we demonstrate that TbetaRIII functions as a BMP cell surface receptor. TbetaRIII directly and specifically binds to multiple members of the BMP subfamily, including BMP-2, BMP-4, BMP-7, and GDF-5, with similar kinetics and ligand binding domains as previously identified for TGF-beta. TbetaRIII also enhances ligand binding to the BMP type I receptors, whereas short hairpin RNA-mediated silencing of endogenous TbetaRIII attenuates BMP-mediated Smad1 phosphorylation. Using a biologically relevant model for TbetaRIII function, we demonstrate that BMP-2 specifically stimulates TbetaRIII-mediated epithelial to mesenchymal cell transformation. The ability of TbetaRIII to serve as a cell surface receptor and mediate BMP, inhibin, and TGF-beta signaling suggests a broader role for TbetaRIII in orchestrating TGF-beta superfamily signaling.

Authors
Kirkbride, KC; Townsend, TA; Bruinsma, MW; Barnett, JV; Blobe, GC
MLA Citation
Kirkbride, KC, Townsend, TA, Bruinsma, MW, Barnett, JV, and Blobe, GC. "Bone morphogenetic proteins signal through the transforming growth factor-beta type III receptor." J Biol Chem 283.12 (March 21, 2008): 7628-7637.
PMID
18184661
Source
pubmed
Published In
The Journal of biological chemistry
Volume
283
Issue
12
Publish Date
2008
Start Page
7628
End Page
7637
DOI
10.1074/jbc.M704883200

TbetaRIII suppresses non-small cell lung cancer invasiveness and tumorigenicity.

The transforming growth factor-beta (TGF-beta) superfamily has essential roles in lung development, regulating cell proliferation, branching morphogenesis, differentiation and apoptosis. Although most lung cancers become resistant to the tumor suppressor effects of TGF-beta, and loss or mutation of one of the components of the TGF-beta signaling pathway, including TbetaRII, Smad2 and Smad4 have been reported, mutations are not common in non-small cell lung cancer (NSCLC). Here we demonstrate that the TGF-beta superfamily co-receptor, the type III TGF-beta receptor (TbetaRIII or betaglycan) is lost in the majority of NSCLC specimens at the mRNA and protein levels, with loss correlating with increased tumor grade and disease progression. Loss of heterozygosity at the TGFBR3 genomic locus occurs in 38.5% of NSCLC specimens and correlates with decreased TbetaRIII expression, suggesting loss of heterozygosity as one mechanism for TbetaRIII loss. In the H460 cell model of NSCLC, restoring TbetaRIII expression decreased colony formation in soft agar. In the A549 cell model of NSCLC, restoring TbetaRIII expression significantly decreased cellular migration and invasion through Matrigel, in the presence and absence of TGF-beta1, and decreased tumorigenicity in vivo. In a reciprocal manner, shRNA-mediated silencing of endogenous TbetaRIII expression enhanced invasion through Matrigel. Mechanistically, TbetaRIII functions, at least in part, through undergoing ectodomain shedding, generating soluble TbetaRIII, which is able to inhibit cellular invasiveness. Taken together, these results support TbetaRIII as a novel tumor suppressor gene that is commonly lost in NSCLC resulting in a functional increase in cellular migration, invasion and anchorage-independent growth of lung cancer cells.

Authors
Finger, EC; Turley, RS; Dong, M; How, T; Fields, TA; Blobe, GC
MLA Citation
Finger, EC, Turley, RS, Dong, M, How, T, Fields, TA, and Blobe, GC. "TbetaRIII suppresses non-small cell lung cancer invasiveness and tumorigenicity." Carcinogenesis 29.3 (March 2008): 528-535.
PMID
18174241
Source
pubmed
Published In
Carcinogenesis
Volume
29
Issue
3
Publish Date
2008
Start Page
528
End Page
535
DOI
10.1093/carcin/bgm289

Loss of type III transforming growth factor beta receptor expression increases motility and invasiveness associated with epithelial to mesenchymal transition during pancreatic cancer progression.

Epithelial to mesenchymal transitions (EMTs) contribute to increases in cellular motility and invasiveness during embryonic development and tumorigenesis. The transforming growth factor beta (TGF-beta) signaling pathway is a key regulator of EMT. The TGF-beta superfamily coreceptor, the type III TGF-beta receptor (TbetaRIII or betaglycan), is required for EMT during embryonic heart development and palate fusion. Here, we establish that in a pancreatic cancer model of EMT, TbetaRIII expression is specifically lost during EMT at the mRNA and protein levels, whereas levels of the TGF-beta type I and type II receptors are maintained at the mRNA level. Loss of TbetaRIII expression at the protein level precedes the loss of E-cadherin and cytoskeletal reorganization during early stages of EMT. However, maintaining TbetaRIII expression does not block these aspects of EMT, but instead suppresses the increased motility and invasiveness associated with EMT. Reciprocally, shRNA-mediated knockdown of endogenous TbetaRIII increases cellular motility without affecting Snail or E-cadherin levels. The ability of TbetaRIII to suppress motility and invasiveness does not depend on its cytoplasmic domain or its coreceptor function. Instead, this suppression of invasion is partially mediated by ectodomain shedding of TbetaRIII, generating soluble TbetaRIII (sTbetaRIII). In human pancreatic cancer specimens, TbetaRIII expression decreases at both the mRNA and protein levels, with the degree of loss correlating with worsening tumor grade. Taken together, these studies support a role for loss of TbetaRIII expression during the EMT of pancreatic cancer progression, with a specific role for sTbetaRIII in suppressing EMT-associated increases in motility and invasion.

Authors
Gordon, KJ; Dong, M; Chislock, EM; Fields, TA; Blobe, GC
MLA Citation
Gordon, KJ, Dong, M, Chislock, EM, Fields, TA, and Blobe, GC. "Loss of type III transforming growth factor beta receptor expression increases motility and invasiveness associated with epithelial to mesenchymal transition during pancreatic cancer progression." Carcinogenesis 29.2 (February 2008): 252-262.
PMID
17999987
Source
pubmed
Published In
Carcinogenesis
Volume
29
Issue
2
Publish Date
2008
Start Page
252
End Page
262
DOI
10.1093/carcin/bgm249

The type III TGF-beta receptor signals through both Smad3 and the p38 MAP kinase pathways to contribute to inhibition of cell proliferation.

Transforming growth factor beta (TGFbeta) has an important role as a negative regulator of cellular proliferation. The type III transforming growth factor beta receptor (TbetaRIII) has an emerging role as both a TGFbeta superfamily co-receptor and in mediating signaling through its cytoplasmic domain. In L6 myoblasts, TbetaRIII expression enhanced TGFbeta1-mediated growth inhibition, with this effect mediated, in part, by the TbetaRIII cytoplasmic domain. The effects of TbetaRIII were not due to altered ligand presentation or to differences in Smad2 phosphorylation. Instead, TbetaRIII specifically increased Smad3 phosphorylation, both basal and TGFbeta-stimulated Smad3 nuclear localization and Smad3-dependent activation of reporter genes independent of its cytoplasmic domain. Conversely, SB431542, a type I transforming growth factor beta receptor (TbetaRI) inhibitor, as well as dominant-negative Smad3 specifically and significantly abrogated the effects of TbetaRIII on TGFbeta1-mediated inhibition of proliferation. TbetaRIII also specifically increased p38 phosphorylation, and SB203580, a p38 kinase inhibitor, specifically and significantly abrogated the effects of TbetaRIII/TGFbeta1-mediated inhibition of proliferation in L6 myoblasts and in primary human epithelial cells. Importantly, treatment with the TbetaRI and p38 inhibitors together had additive effects on abrogating TbetaRIII/TGFbeta1-mediated inhibition of proliferation. In a reciprocal manner, short hairpin RNA-mediated knockdown of endogenous TbetaRIII in various human epithelial cells attenuated TGFbeta1-mediated inhibition of proliferation. Taken together, these data demonstrate that TbetaRIII contributes to and enhances TGFbeta-mediated growth inhibition through both TbetaRI/Smad3-dependent and p38 mitogen-activated protein kinase pathways.

Authors
You, HJ; Bruinsma, MW; How, T; Ostrander, JH; Blobe, GC
MLA Citation
You, HJ, Bruinsma, MW, How, T, Ostrander, JH, and Blobe, GC. "The type III TGF-beta receptor signals through both Smad3 and the p38 MAP kinase pathways to contribute to inhibition of cell proliferation." Carcinogenesis 28.12 (December 2007): 2491-2500.
PMID
17768179
Source
pubmed
Published In
Carcinogenesis
Volume
28
Issue
12
Publish Date
2007
Start Page
2491
End Page
2500
DOI
10.1093/carcin/bgm195

The interaction of endoglin with beta-arrestin2 regulates transforming growth factor-beta-mediated ERK activation and migration in endothelial cells.

In endothelial cells, transforming growth factor beta (TGF-beta) signals through two distinct pathways to regulate endothelial cell proliferation and migration, the ALK-1/Smads 1/5/8 pathway and the ALK-5/Smads 2/3 pathway. TGF-beta signaling through these pathways is further regulated in endothelial cells by the endothelial specific TGF-beta superfamily co-receptor, endoglin. The importance of endoglin, ALK-1, and ALK-5 in endothelial biology is underscored by the embryonic lethal phenotypes of knock-outs in mice due to defects in angiogenesis, and by the presence of disease-causing mutations in these genes in human vascular diseases. However, the mechanism of action of endoglin is not well defined. Here we define a novel interaction between endoglin and the scaffolding protein beta-arrestin2. Both co-immunoprecipitation and fluorescence confocal studies demonstrate the specific interaction between endoglin and beta-arrestin2 in endothelial cells, enhanced by ALK-1 and to a lesser extent by the type II TGF-beta receptor. The endoglin/beta-arrestin2 interaction results in endoglin internalization and co-accumulation of endoglin and beta-arrestin2 in endocytic vesicles. Whereas endoglin did not have a direct impact on either Smad 2/3 or Smad 1/5/8 activation, endoglin antagonized TGF-beta-mediated ERK signaling, altered the subcellular distribution of activated ERK, and inhibited endothelial cell migration in a manner dependent on the ability of endoglin to interact with beta-arrestin2. Reciprocally, small interfering RNA-mediated silencing of endogenous beta-arrestin2 expression restored TGF-beta-mediated ERK activation and increased endothelial cell migration in an endoglin-dependent manner. These studies define a novel function for endoglin, and further expand the roles mediated by the ubiquitous scaffolding protein beta-arrestin2.

Authors
Lee, NY; Blobe, GC
MLA Citation
Lee, NY, and Blobe, GC. "The interaction of endoglin with beta-arrestin2 regulates transforming growth factor-beta-mediated ERK activation and migration in endothelial cells." J Biol Chem 282.29 (July 20, 2007): 21507-21517.
PMID
17540773
Source
pubmed
Published In
The Journal of biological chemistry
Volume
282
Issue
29
Publish Date
2007
Start Page
21507
End Page
21517
DOI
10.1074/jbc.M700176200

Loss of betaglycan expression in ovarian cancer: role in motility and invasion.

The transforming growth factor-beta (TGF-beta) superfamily members, TGF-beta, activin, and inhibin, all have prominent roles in regulating normal ovarian function. Betaglycan, or the type III TGF-beta receptor, is a coreceptor that regulates TGF-beta, activin, and inhibin signaling. Here, we show that betaglycan expression is frequently decreased or lost in epithelial derived ovarian cancer at both the mRNA and protein level, with the degree of loss correlating with tumor grade. Treatment of ovarian cancer cell lines with the methyltransferase inhibitor 5-aza-2-deoxycytidine and the histone deacetylase inhibitor trichostatin A resulted in significant synergistic induction of betaglycan message levels and increased betaglycan protein expression, indicating that epigenetic silencing may play a role in the loss of betaglycan expression observed in ovarian cancer. Although restoring betaglycan expression in Ovca429 ovarian cancer cells is not sufficient to restore TGF-beta-mediated inhibition of proliferation, betaglycan significantly inhibits ovarian cancer cell motility and invasiveness. Furthermore, betaglycan specifically enhances the antimigratory effects of inhibin and the ability of inhibin to repress matrix metalloproteinase levels in these cells. These results show, for the first time, epigenetic regulation of betaglycan expression in ovarian cancer, and a novel role for betaglycan in regulating ovarian cancer motility and invasiveness.

Authors
Hempel, N; How, T; Dong, M; Murphy, SK; Fields, TA; Blobe, GC
MLA Citation
Hempel, N, How, T, Dong, M, Murphy, SK, Fields, TA, and Blobe, GC. "Loss of betaglycan expression in ovarian cancer: role in motility and invasion." Cancer Res 67.11 (June 1, 2007): 5231-5238.
PMID
17522389
Source
pubmed
Published In
Cancer Research
Volume
67
Issue
11
Publish Date
2007
Start Page
5231
End Page
5238
DOI
10.1158/0008-5472.CAN-07-0035

Bevacizumab, oxaliplatin, and capecitabine with radiation therapy in rectal cancer: Phase I trial results.

PURPOSE: The overexpression of vascular endothelial growth factor (VEGF) is associated with poor outcomes in colorectal cancer patients. Bevacizumab, a VEGF inhibitor, enhances the effects of chemotherapy and radiation therapy on tumor cytotoxicity in preclinical models, including colorectal cancer. A Phase I trial was undertaken to evaluate the combination of bevacizumab, capecitabine, oxaliplatin, and radiation therapy in patients with rectal cancer. METHODS AND MATERIALS: Patients with pathologically confirmed adenocarcinoma of the rectum were eligible. Pretreatment staging included computerized tomography, endoscopic ultrasound, and surgical evaluation. Patients received 50.4 Gy of external beam radiation therapy (EBRT) to the tumor in 28 fractions. Capecitabine, oxaliplatin, and bevacizumab were administered concurrently with radiation therapy. After EBRT completion, patients were restaged and evaluated for surgery. Primary endpoints included the determination of dose-limiting toxicity and a recommended Phase II dose, non dose-limiting toxicity, and preliminary radiographic and pathologic response rates. RESULTS: Eleven patients were enrolled. All were evaluable for toxicity and efficacy. Dose level 2 was associated with unacceptable toxicity (primarily diarrhea). Dose level 1 had an acceptable toxicity profile. The recommended Phase II dose in our study was bevacizumab 15 mg/kg Day 1 + 10 mg/kg Days 8 and 22, oxaliplatin 50 mg/m2 weekly, and capecitabine 625 mg/m2 bid during radiation days. Six patients had clinical responses. Two patients had a pathologic complete response, and 3 had microscopic disease only. One patient experienced a postoperative abscess, one a syncopal episode during adjuvant chemotherapy, and one a subclinical myocardial infarction during adjuvant chemotherapy. CONCLUSIONS: The combination of bevacizumab, capecitabine, oxaliplatin, and radiation therapy in rectal cancer was tolerable, with encouraging response rates. Further investigation with this regimen is being pursued in a Phase II setting.

Authors
Czito, BG; Bendell, JC; Willett, CG; Morse, MA; Blobe, GC; Tyler, DS; Thomas, J; Ludwig, KA; Mantyh, CR; Ashton, J; Yu, D; Hurwitz, HI
MLA Citation
Czito, BG, Bendell, JC, Willett, CG, Morse, MA, Blobe, GC, Tyler, DS, Thomas, J, Ludwig, KA, Mantyh, CR, Ashton, J, Yu, D, and Hurwitz, HI. "Bevacizumab, oxaliplatin, and capecitabine with radiation therapy in rectal cancer: Phase I trial results." Int J Radiat Oncol Biol Phys 68.2 (June 1, 2007): 472-478.
PMID
17498568
Source
pubmed
Published In
International Journal of Radiation Oncology, Biology, Physics
Volume
68
Issue
2
Publish Date
2007
Start Page
472
End Page
478
DOI
10.1016/j.ijrobp.2007.02.001

The role of the type III TGF-beta receptor in prostate cancer

Authors
Turley, RS; Finger, EC; Fields, TA; Blobe, GC
MLA Citation
Turley, RS, Finger, EC, Fields, TA, and Blobe, GC. "The role of the type III TGF-beta receptor in prostate cancer." April 2007.
Source
wos-lite
Published In
The Journal of Urology
Volume
177
Issue
4
Publish Date
2007
Start Page
94
End Page
94

A Phase I study of capecitabine, carboplatin, and paclitaxel with external beam radiation therapy for esophageal carcinoma.

PURPOSE: Concurrent chemotherapy and radiation therapy (RT) are used to treat patients with esophageal cancer. The optimal combination of chemotherapeutic agents with RT is undefined. We evaluated a combination of capecitabine, carboplatin, and paclitaxel with RT in a phase I study. METHODS AND MATERIALS: Patients with squamous cell carcinoma or adenocarcinoma of the esophagus initially received capecitabine, carboplatin, and paclitaxel with RT (1.8 Gy daily to 50.4 Gy). After completion, patients were restaged and evaluated for surgery. Primary endpoints included determination of dose-limiting toxicities (DLT) and a recommended phase II dose, non-DLT, and preliminary radiographic and pathologic response rates. RESULTS: Thirteen patients were enrolled (10 men, 3 women). All were evaluable for toxicity and efficacy. Two of 3 patients at dose level 1 (capecitabine 825 mg/m(2) twice daily on RT days, carboplatin area under the curve (AUC) 2 weekly, paclitaxel 60 mg/m(2) weekly) had DLT (both Grade 4 esophagitis). Of these 3, 2 underwent esophagectomy and had pathologic complete response (pCR). Ten patients were then enrolled at dose level -1 (capecitabine 600 mg/m(2) twice daily, carboplatin AUC 1.5, paclitaxel 45 mg/m(2)). Overall, 3 of 10 patients at dose level -1 developed DLT (2 Grade 3 esophagitis, 1 Grade 3 hypotension). Esophagectomy was performed in 6 of 10 patients. All patients had pathologic downstaging and 2 of 6 had pCR. CONCLUSIONS: The maximally tolerated/recommended phase II doses were capecitabine 600 mg/m(2) twice daily, carboplatin AUC 1.5 weekly, and paclitaxel 45 mg/m(2) weekly with RT to 50.4 Gy. In our small study, this regimen appears active but is accompanied by significant toxicities, primarily esophagitis.

Authors
Czito, BG; Kelsey, CR; Hurwitz, HI; Willett, CG; Morse, MA; Blobe, GC; Fernando, NH; D'Amico, TA; Harpole, DH; Honeycutt, W; Yu, D; Bendell, JC
MLA Citation
Czito, BG, Kelsey, CR, Hurwitz, HI, Willett, CG, Morse, MA, Blobe, GC, Fernando, NH, D'Amico, TA, Harpole, DH, Honeycutt, W, Yu, D, and Bendell, JC. "A Phase I study of capecitabine, carboplatin, and paclitaxel with external beam radiation therapy for esophageal carcinoma." Int J Radiat Oncol Biol Phys 67.4 (March 15, 2007): 1002-1007.
PMID
17197129
Source
pubmed
Published In
International Journal of Radiation Oncology, Biology, Physics
Volume
67
Issue
4
Publish Date
2007
Start Page
1002
End Page
1007
DOI
10.1016/j.ijrobp.2006.10.027

The type III transforming growth factor-beta receptor as a novel tumor suppressor gene in prostate cancer.

The transforming growth factor-beta (TGF-beta) signaling pathway has an important role in regulating normal prostate epithelium, inhibiting proliferation, differentiation, and both androgen deprivation-induced and androgen-independent apoptosis. During prostate cancer formation, most prostate cancer cells become resistant to these homeostatic effects of TGF-beta. Although the loss of expression of either the type I (TbetaRI) or type II (TbetaRII) TGF-beta receptor has been documented in approximately 30% of prostate cancers, most prostate cancers become TGF-beta resistant without mutation or deletion of TbetaRI, TbetaRII, or Smads2, 3, and 4, and thus, the mechanism of resistance remains to be defined. Here, we show that type III TGF-beta receptor (TbetaRIII or betaglycan) expression is decreased or lost in the majority of human prostate cancers as compared with benign prostate tissue at both the mRNA and protein level. Loss of TbetaRIII expression correlates with advancing tumor stage and a higher probability of prostate-specific antigen (PSA) recurrence, suggesting a role in prostate cancer progression. The loss of TbetaRIII expression is mediated by the loss of heterozygosity at the TGFBR3 genomic locus and epigenetic regulation of the TbetaRIII promoter. Functionally, restoring TbetaRIII expression in prostate cancer cells potently decreases cell motility and cell invasion through Matrigel in vitro and prostate tumorigenicity in vivo. Taken together, these studies define the loss of TbetaRIII expression as a common event in human prostate cancer and suggest that this loss is important for prostate cancer progression through effects on cell motility, invasiveness, and tumorigenicity.

Authors
Turley, RS; Finger, EC; Hempel, N; How, T; Fields, TA; Blobe, GC
MLA Citation
Turley, RS, Finger, EC, Hempel, N, How, T, Fields, TA, and Blobe, GC. "The type III transforming growth factor-beta receptor as a novel tumor suppressor gene in prostate cancer." Cancer Res 67.3 (February 1, 2007): 1090-1098.
PMID
17283142
Source
pubmed
Published In
Cancer Research
Volume
67
Issue
3
Publish Date
2007
Start Page
1090
End Page
1098
DOI
10.1158/0008-5472.CAN-06-3117

The type III TGF-beta receptor suppresses breast cancer progression.

The TGF-beta signaling pathway has a complex role in regulating mammary carcinogenesis. Here we demonstrate that the type III TGF-beta receptor (TbetaRIII, or betaglycan), a ubiquitously expressed TGF-beta coreceptor, regulated breast cancer progression and metastasis. Most human breast cancers lost TbetaRIII expression, with loss of heterozygosity of the TGFBR3 gene locus correlating with decreased TbetaRIII expression. TbetaRIII expression decreased during breast cancer progression, and low TbetaRIII levels predicted decreased recurrence-free survival in breast cancer patients. Restoring TbetaRIII expression in breast cancer cells dramatically inhibited tumor invasiveness in vitro and tumor invasion, angiogenesis, and metastasis in vivo. TbetaRIII appeared to inhibit tumor invasion by undergoing ectodomain shedding and producing soluble TbetaRIII, which binds and sequesters TGF-beta to decrease TGF-beta signaling and reduce breast cancer cell invasion and tumor-induced angiogenesis. Our results indicate that loss of TbetaRIII through allelic imbalance is a frequent genetic event during human breast cancer development that increases metastatic potential.

Authors
Dong, M; How, T; Kirkbride, KC; Gordon, KJ; Lee, JD; Hempel, N; Kelly, P; Moeller, BJ; Marks, JR; Blobe, GC
MLA Citation
Dong, M, How, T, Kirkbride, KC, Gordon, KJ, Lee, JD, Hempel, N, Kelly, P, Moeller, BJ, Marks, JR, and Blobe, GC. "The type III TGF-beta receptor suppresses breast cancer progression." J Clin Invest 117.1 (January 2007): 206-217.
PMID
17160136
Source
pubmed
Published In
Journal of Clinical Investigation
Volume
117
Issue
1
Publish Date
2007
Start Page
206
End Page
217
DOI
10.1172/JCI29293

Role of transforming growth factor-beta in hematologic malignancies.

The transforming growth factor-beta (TGF-beta) signaling pathway is an essential regulator of cellular processes, including proliferation, differentiation, migration, and cell survival. During hematopoiesis, the TGF-beta signaling pathway is a potent negative regulator of proliferation while stimulating differentiation and apoptosis when appropriate. In hematologic malignancies, including leukemias, myeloproliferative disorders, lymphomas, and multiple myeloma, resistance to these homeostatic effects of TGF-beta develops. Mechanisms for this resistance include mutation or deletion of members of the TGF-beta signaling pathway and disruption of the pathway by oncoproteins. These alterations define a tumor suppressor role for the TGF-beta pathway in human hematologic malignancies. On the other hand, elevated levels of TGF-beta can promote myelofibrosis and the pathogenesis of some hematologic malignancies through their effects on the stroma and immune system. Advances in the TGF-beta signaling field should enable targeting of the TGF-beta signaling pathway for the treatment of hematologic malignancies.

Authors
Dong, M; Blobe, GC
MLA Citation
Dong, M, and Blobe, GC. "Role of transforming growth factor-beta in hematologic malignancies." Blood 107.12 (June 15, 2006): 4589-4596. (Review)
PMID
16484590
Source
pubmed
Published In
Blood
Volume
107
Issue
12
Publish Date
2006
Start Page
4589
End Page
4596
DOI
10.1182/blood-2005-10-4169

Increased toxicity with gefitinib, capecitabine, and radiation therapy in pancreatic and rectal cancer: phase I trial results.

PURPOSE: Overexpression of epidermal growth factor receptor (EGFR) has been associated with aggressive tumor phenotypes, chemotherapy, and radiation resistance, as well as poor survival in preclinical and clinical models. The EGFR inhibitor gefitinib potentiates chemotherapy and radiation tumor cytotoxicity in preclinical models, including pancreatic and colorectal cancer. We initiated two phase I trials assessing the combination of gefitinib, capecitabine, and radiation in patients with localized pancreatic and rectal cancer. PATIENTS AND METHODS: Patients with pathologically confirmed adenocarcinoma of the pancreas and rectum were eligible. Pretreatment staging included computed tomography, endoscopic ultrasound, and surgical evaluation. Patients received 50.4 Gy of external-beam radiation therapy to the tumor in 28 fractions. Capecitabine and gefitinib were administered throughout the radiation course. Following completion, patients were restaged and considered for resection. Primary end points included determination of dose-limiting toxicity (DLT) and a phase II dose; secondary end points included determination of non-DLTs and preliminary radiographic and pathologic response rates. RESULTS: Ten patients were entered in the pancreatic study and six in the rectal study. DLT was seen in six of 10 patients in the pancreatic study and two of six patients in the rectal study. The primary DLT in both studies was diarrhea. Two patients developed arterial thrombi. CONCLUSION: The combination of gefitinib, capecitabine, and radiation in pancreatic and rectal cancer patients resulted in significant toxicity. A recommended phase II dose was not determined in either of our studies. Further investigation with this combination should be approached with caution.

Authors
Czito, BG; Willett, CG; Bendell, JC; Morse, MA; Tyler, DS; Fernando, NH; Mantyh, CR; Blobe, GC; Honeycutt, W; Yu, D; Clary, BM; Pappas, TN; Ludwig, KA; Hurwitz, HI
MLA Citation
Czito, BG, Willett, CG, Bendell, JC, Morse, MA, Tyler, DS, Fernando, NH, Mantyh, CR, Blobe, GC, Honeycutt, W, Yu, D, Clary, BM, Pappas, TN, Ludwig, KA, and Hurwitz, HI. "Increased toxicity with gefitinib, capecitabine, and radiation therapy in pancreatic and rectal cancer: phase I trial results." J Clin Oncol 24.4 (February 1, 2006): 656-662.
PMID
16446337
Source
pubmed
Published In
Journal of Clinical Oncology
Volume
24
Issue
4
Publish Date
2006
Start Page
656
End Page
662
DOI
10.1200/JCO.2005.04.1749

Cell-surface co-receptors: emerging roles in signaling and human disease.

Extracellular signals are transmitted to cells through two classes of cell-surface receptors: signaling receptors that directly transduce signals and signaling co-receptors that bind ligand but that, traditionally, have not been thought to signal directly. Signaling co-receptors modulate the ligand binding and signaling of their respective signaling receptors. In recent years, roles for co-receptors have expanded to include essential functions in morphogen gradient formation, localizing signaling, signaling independently, regulating cell adhesion and orchestrating the signaling of several pathways. The importance of signaling co-receptors is demonstrated by their ubiquitous expression, their conservation during evolution, their prominent role in signaling cascades, their indispensable role during development and their frequent mutation or altered expression in human disease.

Authors
Kirkbride, KC; Ray, BN; Blobe, GC
MLA Citation
Kirkbride, KC, Ray, BN, and Blobe, GC. "Cell-surface co-receptors: emerging roles in signaling and human disease." Trends Biochem Sci 30.11 (November 2005): 611-621. (Review)
PMID
16185874
Source
pubmed
Published In
Trends in Biochemical Sciences
Volume
30
Issue
11
Publish Date
2005
Start Page
611
End Page
621
DOI
10.1016/j.tibs.2005.09.003

Role of transforming growth factor Beta in human cancer.

Transforming growth factor beta (TGF-beta) is a ubiquitous and essential regulator of cellular and physiologic processes including proliferation, differentiation, migration, cell survival, angiogenesis, and immunosurveillance. Alterations in the TGF-beta signaling pathway, including mutation or deletion of members of the signaling pathway and resistance to TGF-beta-mediated inhibition of proliferation are frequently observed in human cancers. Although these alterations define a tumor suppressor role for the TGF-beta pathway in human cancer, TGF-beta also mediates tumor-promoting effects, either through differential effects on tumor and stromal cells or through a fundamental alteration in the TGF-beta responsiveness of the tumor cells themselves. TGF-beta and members of the TGF-beta signaling pathway are being evaluated as prognostic or predictive markers for cancer patients. Ongoing advances in understanding the TGF-beta signaling pathway will enable targeting of this pathway for the chemoprevention and treatment of human cancers.

Authors
Elliott, RL; Blobe, GC
MLA Citation
Elliott, RL, and Blobe, GC. "Role of transforming growth factor Beta in human cancer." J Clin Oncol 23.9 (March 20, 2005): 2078-2093. (Review)
PMID
15774796
Source
pubmed
Published In
Journal of Clinical Oncology
Volume
23
Issue
9
Publish Date
2005
Start Page
2078
End Page
2093
DOI
10.1200/JCO.2005.02.047

Significance of histological response to preoperative chemoradiotherapy for pancreatic cancer.

BACKGROUND: Neoadjuvant (preoperative) chemoradiotherapy (CRT) for pancreatic cancer offers theoretical advantages over the standard approach of surgery followed by adjuvant CRT. We hypothesized that histological responses to CRT would be significant prognostic factors in patients undergoing neoadjuvant CRT followed by resection. METHODS: Since 1994, 193 patients with biopsy-proven pancreatic adenocarcinoma have completed neoadjuvant CRT, and 70 patients have undergone resection. Specimens were retrospectively examined by an individual pathologist for histological responses (tumor necrosis, tumor fibrosis, and residual tumor load) and immunohistochemical staining for p53 and epidermal growth factor receptor. Factors influencing overall survival were analyzed with the Kaplan-Meier (univariate) and Cox proportional hazards (multivariate) methods. RESULTS: The estimated overall survival (median +/- SE) in the entire group of patients undergoing resection was 23 +/- 4.2 months, with an estimated 3-year survival of 37% +/- 6.6% and a median follow-up of 28 months. Complete histological responses occurred in 6% of patients. Overexpression of p53 was more common in patients with large residual tumor loads. Tumor necrosis was an independent negative prognostic factor, as were positive lymph nodes, a large residual tumor load, and poor tumor differentiation. CONCLUSIONS: Histological response to neoadjuvant CRT--as measured by residual tumor load--may be useful as a surrogate marker for treatment efficacy. Characterization of the tumor cells that survive neoadjuvant CRT may help us to identify new or more appropriate targets for systemic therapy.

Authors
White, RR; Xie, HB; Gottfried, MR; Czito, BG; Hurwitz, HI; Morse, MA; Blobe, GC; Paulson, EK; Baillie, J; Branch, MS; Jowell, PS; Clary, BM; Pappas, TN; Tyler, DS
MLA Citation
White, RR, Xie, HB, Gottfried, MR, Czito, BG, Hurwitz, HI, Morse, MA, Blobe, GC, Paulson, EK, Baillie, J, Branch, MS, Jowell, PS, Clary, BM, Pappas, TN, and Tyler, DS. "Significance of histological response to preoperative chemoradiotherapy for pancreatic cancer." Ann Surg Oncol 12.3 (March 2005): 214-221.
PMID
15827813
Source
pubmed
Published In
Annals of Surgical Oncology
Volume
12
Issue
3
Publish Date
2005
Start Page
214
End Page
221
DOI
10.1245/ASO.2005.03.105

Development of human protein reference database as an initial platform for approaching systems biology in humans.

Human Protein Reference Database (HPRD) is an object database that integrates a wealth of information relevant to the function of human proteins in health and disease. Data pertaining to thousands of protein-protein interactions, posttranslational modifications, enzyme/substrate relationships, disease associations, tissue expression, and subcellular localization were extracted from the literature for a nonredundant set of 2750 human proteins. Almost all the information was obtained manually by biologists who read and interpreted >300,000 published articles during the annotation process. This database, which has an intuitive query interface allowing easy access to all the features of proteins, was built by using open source technologies and will be freely available at http://www.hprd.org to the academic community. This unified bioinformatics platform will be useful in cataloging and mining the large number of proteomic interactions and alterations that will be discovered in the postgenomic era.

Authors
Peri, S; Navarro, JD; Amanchy, R; Kristiansen, TZ; Jonnalagadda, CK; Surendranath, V; Niranjan, V; Muthusamy, B; Gandhi, TKB; Gronborg, M; Ibarrola, N; Deshpande, N; Shanker, K; Shivashankar, HN; Rashmi, BP; Ramya, MA; Zhao, Z; Chandrika, KN; Padma, N; Harsha, HC; Yatish, AJ; Kavitha, MP; Menezes, M; Choudhury, DR; Suresh, S; Ghosh, N; Saravana, R; Chandran, S; Krishna, S; Joy, M; Anand, SK; Madavan, V; Joseph, A; Wong, GW; Schiemann, WP; Constantinescu, SN; Huang, L; Khosravi-Far, R; Steen, H et al.
MLA Citation
Peri, S, Navarro, JD, Amanchy, R, Kristiansen, TZ, Jonnalagadda, CK, Surendranath, V, Niranjan, V, Muthusamy, B, Gandhi, TKB, Gronborg, M, Ibarrola, N, Deshpande, N, Shanker, K, Shivashankar, HN, Rashmi, BP, Ramya, MA, Zhao, Z, Chandrika, KN, Padma, N, Harsha, HC, Yatish, AJ, Kavitha, MP, Menezes, M, Choudhury, DR, Suresh, S, Ghosh, N, Saravana, R, Chandran, S, Krishna, S, Joy, M, Anand, SK, Madavan, V, Joseph, A, Wong, GW, Schiemann, WP, Constantinescu, SN, Huang, L, Khosravi-Far, R, and Steen, H et al. "Development of human protein reference database as an initial platform for approaching systems biology in humans." Genome Res 13.10 (October 2003): 2363-2371.
PMID
14525934
Source
pubmed
Published In
Genome research
Volume
13
Issue
10
Publish Date
2003
Start Page
2363
End Page
2371
DOI
10.1101/gr.1680803

Beta-arrestin 2 mediates endocytosis of type III TGF-beta receptor and down-regulation of its signaling.

beta-Arrestins bind to activated seven transmembrane-spanning (7TMS) receptors (G protein-coupled receptors) after the receptors are phosphorylated by G protein-coupled receptor kinases (GRKs), thereby regulating their signaling and internalization. Here, we demonstrate an unexpected and analogous role of beta-arrestin 2 (betaarr2) for the single transmembrane-spanning type III transforming growth factor-beta (TGF-beta) receptor (TbetaRIII, also referred to as betaglycan). Binding of betaarr2 to TbetaRIII was also triggered by phosphorylation of the receptor on its cytoplasmic domain (likely at threonine 841). However, such phosphorylation was mediated by the type II TGF-beta receptor (TbetaRII), which is itself a kinase, rather than by a GRK. Association with betaarr2 led to internalization of both receptors and down-regulation of TGF-beta signaling. Thus, the regulatory actions of beta-arrestins are broader than previously appreciated, extending to the TGF-beta receptor family as well.

Authors
Chen, W; Kirkbride, KC; How, T; Nelson, CD; Mo, J; Frederick, JP; Wang, X-F; Lefkowitz, RJ; Blobe, GC
MLA Citation
Chen, W, Kirkbride, KC, How, T, Nelson, CD, Mo, J, Frederick, JP, Wang, X-F, Lefkowitz, RJ, and Blobe, GC. "Beta-arrestin 2 mediates endocytosis of type III TGF-beta receptor and down-regulation of its signaling." Science 301.5638 (September 5, 2003): 1394-1397.
PMID
12958365
Source
pubmed
Published In
Science
Volume
301
Issue
5638
Publish Date
2003
Start Page
1394
End Page
1397
DOI
10.1126/science.1083195

Inhibiting the TGF-beta signalling pathway as a means of cancer immunotherapy.

Cancers have developed numerous mechanisms for escaping the immune response, either by successfully evading a fully functional immune system or by actively suppressing the immune system so that they are no longer recognised or effectively eliminated. Current evidence supports active cancer cell-mediated immunosuppression via the secretion of the potent immunosuppressive cytokine, transforming growth factor-beta (TGF-beta), as the most general and potent mechanism for human cancer cells to escape the immune system. Efforts to bypass TGF-beta-mediated immunosuppression thereby represent an attractive therapeutic strategy for the chemoprevention and treatment of human cancers, both by directly increasing the efficacy of immunosurveillance and by increasing the efficacy of current immunotherapy strategies. Current approaches are limited by their nonspecific effects on the TGF-beta signalling pathway, as TGF-beta pathways which specifically mediate immunosuppression have not yet been defined. Future efforts should be directed towards elucidating specific TGF-beta pathways so that these can be targeted for the chemoprevention and treatment of human cancers.

Authors
Kirkbride, KC; Blobe, GC
MLA Citation
Kirkbride, KC, and Blobe, GC. "Inhibiting the TGF-beta signalling pathway as a means of cancer immunotherapy." Expert Opin Biol Ther 3.2 (April 2003): 251-261. (Review)
PMID
12662140
Source
pubmed
Published In
Expert Opinion on Biological Therapy
Volume
3
Issue
2
Publish Date
2003
Start Page
251
End Page
261
DOI
10.1517/14712598.3.2.251

Regulation of ALK-1 signaling by the nuclear receptor LXRbeta.

The transforming growth factor beta (TGF-beta) receptor, ALK-1, is expressed specifically on endothelial cells and is essential for angiogenesis, as demonstrated by its targeted deletion in mice and its mutation in the human disease hereditary hemorrhagic telangiectasia. Although ALK-1 and another endothelial-specific TGF-beta receptor, endoglin, both bind TGF-beta with identical isoform specificity and form a complex together, neither has been shown to signal in response to TGF-beta, and the mechanism by which these receptors signal in endothelial cells remains unknown. Here we report the identification of the nuclear receptor liver X receptor beta (LXRbeta) as a modulator/mediator of ALK-1 signaling. The cytoplasmic domain of ALK-1 specifically binds to LXRbeta in vitro and in vivo. Expression of activated ALK-1 results in translocation of LXRbeta from the nuclear compartment to the cytoplasmic compartment. The interaction of activated ALK-1 with LXRbeta in the cytoplasmic compartment results in the specific phosphorylation of LXRbeta by ALK-1, primarily on serine residues. LXRbeta subsequently modulates signaling by ALK-1 and the closely related TGF-beta receptor, ALK-2, as demonstrated by specific and potent inhibition of ALK-1- and ALK-2-mediated transcriptional responses, establishing LXRbeta as a potential modulator/mediator of ALK-1/ALK-2 signaling.

Authors
Mo, J; Fang, SJ; Chen, W; Blobe, GC
MLA Citation
Mo, J, Fang, SJ, Chen, W, and Blobe, GC. "Regulation of ALK-1 signaling by the nuclear receptor LXRbeta." J Biol Chem 277.52 (December 27, 2002): 50788-50794.
PMID
12393874
Source
pubmed
Published In
The Journal of biological chemistry
Volume
277
Issue
52
Publish Date
2002
Start Page
50788
End Page
50794
DOI
10.1074/jbc.M210376200

Context-specific effects of fibulin-5 (DANCE/EVEC) on cell proliferation, motility, and invasion. Fibulin-5 is induced by transforming growth factor-beta and affects protein kinase cascades.

Fibulin-5 (FBLN-5; also known as DANCE or EVEC) is an integrin-binding extracellular matrix protein that mediates endothelial cell adhesion; it is also a calcium-dependent elastin-binding protein that scaffolds cells to elastic fibers, thereby preventing elastinopathy in the skin, lung, and vasculature. Transforming growth factor-beta (TGF-beta) regulates the production of cytokines, growth factors, and extracellular matrix proteins by a variety of cell types and tissues. We show here that TGF-beta stimulates murine 3T3-L1 fibroblasts to synthesize FBLN-5 transcript and protein through a Smad3-independent pathway. Overexpression of FBLN-5 in 3T3-L1 cells increased DNA synthesis and enhanced basal and TGF-beta-stimulated activation of ERK1/ERK2 and p38 mitogen-activated protein kinase (MAPK). FBLN-5 overexpression also augmented the tumorigenicity of human HT1080 fibrosarcoma cells by increasing their DNA synthesis, migration toward fibronectin, and invasion through synthetic basement membranes. In stark contrast, FBLN-5 expression was down-regulated in the majority of metastatic human malignancies, particularly in cancers of the kidney, breast, ovary, and colon. Unlike its proliferative response in fibroblasts, FBLN-5 overexpression in mink lung Mv1Lu epithelial cells resulted in an antiproliferative response, reducing their DNA synthesis and cyclin A expression. Moreover, FBLN-5 synergizes with TGF-beta in stimulating AP-1 activity in Mv1Lu cells, an effect that was abrogated by overexpression of dominant-negative versions of either MKK1 or p38 MAPKalpha. Accordingly, both the stimulation and duration of ERK1/ERK2 and p38 MAPK by TGF-beta was enhanced in Mv1Lu cells expressing FBLN-5. Our findings identify FBLN-5 as a novel TGF-beta-inducible target gene that regulates cell growth and motility in a context-specific manner and affects protein kinase activation by TGF-beta. Our findings also indicate that aberrant FBLN-5 expression likely contributes to tumor development in humans.

Authors
Schiemann, WP; Blobe, GC; Kalume, DE; Pandey, A; Lodish, HF
MLA Citation
Schiemann, WP, Blobe, GC, Kalume, DE, Pandey, A, and Lodish, HF. "Context-specific effects of fibulin-5 (DANCE/EVEC) on cell proliferation, motility, and invasion. Fibulin-5 is induced by transforming growth factor-beta and affects protein kinase cascades." J Biol Chem 277.30 (July 26, 2002): 27367-27377.
PMID
12021267
Source
pubmed
Published In
The Journal of biological chemistry
Volume
277
Issue
30
Publish Date
2002
Start Page
27367
End Page
27377
DOI
10.1074/jbc.M200148200

A novel mechanism for regulating transforming growth factor beta (TGF-beta) signaling. Functional modulation of type III TGF-beta receptor expression through interaction with the PDZ domain protein, GIPC.

Transforming growth factor beta (TGF-beta) mediates its biological effects through three high-affinity cell surface receptors, the TGF-beta type I, type II, and type III receptors, and the Smad family of transcription factors. Although the functions of the type II and type I receptors are well established, the precise role of the type III receptor in TGF-beta signaling remains to be established. While expression cloning signaling molecules downstream of TGF-beta, we cloned GIPC (GAIP-interacting protein, C terminus), a PDZ domain-containing protein. GIPC binds a Class I PDZ binding motif in the cytoplasmic domain of the type III receptor resulting in regulation of expression of the type III receptor at the cell surface. Increased expression of the type III receptor mediated by GIPC enhanced cellular responsiveness to TGF-beta both in terms of inhibition of proliferation and in plasminogen-activating inhibitor (PAI)-based promoter gene induction assays. In all cases, deletion of the Class I PDZ binding motif of the type III receptor prevented the type III receptor from binding to GIPC and abrogated the effects of GIPC on type III receptor expressing cells. These results establish, for the first time, a protein that interacts with the cytoplasmic domain of the type III receptor, determine that expression of the type III receptor is regulated at the protein level and that increased expression of the type III receptor is sufficient to enhance TGF-beta signaling. These results further support an essential, non-redundant role for the type III receptor in TGF-beta signaling.

Authors
Blobe, GC; Liu, X; Fang, SJ; How, T; Lodish, HF
MLA Citation
Blobe, GC, Liu, X, Fang, SJ, How, T, and Lodish, HF. "A novel mechanism for regulating transforming growth factor beta (TGF-beta) signaling. Functional modulation of type III TGF-beta receptor expression through interaction with the PDZ domain protein, GIPC." J Biol Chem 276.43 (October 26, 2001): 39608-39617.
PMID
11546783
Source
pubmed
Published In
The Journal of biological chemistry
Volume
276
Issue
43
Publish Date
2001
Start Page
39608
End Page
39617
DOI
10.1074/jbc.M106831200

Functional roles for the cytoplasmic domain of the type III transforming growth factor beta receptor in regulating transforming growth factor beta signaling.

Transforming growth factor beta (TGF-beta) signals through three high affinity cell surface receptors, TGF-beta type I, type II, and type III receptors. The type III receptor, also known as betaglycan, binds to the type II receptor and is thought to act solely by "presenting" the TGF-beta ligand to the type II receptor. The short cytoplasmic domain of the type III receptor is thought to have no role in TGF-beta signaling because deletion of this domain has no effect on association with the type II receptor, or with the presentation role of the type III receptor. Here we demonstrate that the cytoplasmic domains of the type III and type II receptors interact specifically in a manner dependent on the kinase activity of the type II receptor and the ability of the type II receptor to autophosphorylate. This interaction results in the phosphorylation of the cytoplasmic domain of the type III receptor by the type II receptor. The type III receptor with the cytoplasmic domain deleted is able to bind TGF-beta, to bind the type II receptor, and to enhance TGF-beta binding to the type II receptor but is unable to enhance TGF-beta2 signaling, determining that the cytoplasmic domain is essential for some functions of the type III receptor. The type III receptor functions by selectively binding the autophosphorylated type II receptor via its cytoplasmic domain, thus promoting the preferential formation of a complex between the autophosphorylated type II receptor and the type I receptor and then dissociating from this active signaling complex. These studies, for the first time, elucidate important functional roles of the cytoplasmic domain of the type III receptor and demonstrate that these roles are essential for regulating TGF-beta signaling.

Authors
Blobe, GC; Schiemann, WP; Pepin, MC; Beauchemin, M; Moustakas, A; Lodish, HF; O'Connor-McCourt, MD
MLA Citation
Blobe, GC, Schiemann, WP, Pepin, MC, Beauchemin, M, Moustakas, A, Lodish, HF, and O'Connor-McCourt, MD. "Functional roles for the cytoplasmic domain of the type III transforming growth factor beta receptor in regulating transforming growth factor beta signaling." J Biol Chem 276.27 (July 6, 2001): 24627-24637.
PMID
11323414
Source
pubmed
Published In
The Journal of biological chemistry
Volume
276
Issue
27
Publish Date
2001
Start Page
24627
End Page
24637
DOI
10.1074/jbc.M100188200

Two patients with sarcoma. Case 2. Uterine sarcoma.

Authors
Blobe, GC; Mantel, M; Janicek, M; Demetri, GD
MLA Citation
Blobe, GC, Mantel, M, Janicek, M, and Demetri, GD. "Two patients with sarcoma. Case 2. Uterine sarcoma." J Clin Oncol 18.11 (June 2000): 2343-2344.
PMID
10829056
Source
pubmed
Published In
Journal of Clinical Oncology
Volume
18
Issue
11
Publish Date
2000
Start Page
2343
End Page
2344
DOI
10.1200/JCO.2000.18.11.2343

Role of transforming growth factor beta in human disease.

Authors
Blobe, GC; Schiemann, WP; Lodish, HF
MLA Citation
Blobe, GC, Schiemann, WP, and Lodish, HF. "Role of transforming growth factor beta in human disease." N Engl J Med 342.18 (May 4, 2000): 1350-1358. (Review)
PMID
10793168
Source
pubmed
Published In
The New England journal of medicine
Volume
342
Issue
18
Publish Date
2000
Start Page
1350
End Page
1358
DOI
10.1056/NEJM200005043421807

Case 2. Uterine sarcoma

Authors
Blobe, GC; Mantel, M; Janicek, M; Demetri, GD
MLA Citation
Blobe, GC, Mantel, M, Janicek, M, and Demetri, GD. "Case 2. Uterine sarcoma." Journal of Clinical Oncology 18.11 (2000): 2343-2344.
Source
scival
Published In
Journal of Clinical Oncology
Volume
18
Issue
11
Publish Date
2000
Start Page
2343
End Page
2344

Role of transforming growth factor beta in human disease

Authors
BLOBE, G
MLA Citation
BLOBE, G. "Role of transforming growth factor beta in human disease." N Engl J Med 342 (2000): 1350-1358.
Source
cinii-english
Published In
N Engl J Med
Volume
342
Publish Date
2000
Start Page
1350
End Page
1358
DOI
10.1056/NEJM200005043421807

The p53 tumor suppressor gene in head and neck cancer

Recent advances in recombinant DNA technology have allowed additional insight into the pathogenesis of cancer and may supply new tools to predict the course of disease and provide new methods of treatment. Research into the mutations or deletions of the p53 suppressor gene originally found in cancer tissues has been particularly fruitful and may be linked to future progress in the treatment of patients with head and neck cancers. Some alteration of the p53 gene can be detected in 90% of these cancers. Studies done during the past year suggest that evaluating patients for alterations of p53 may have prognostic value in head and neck cancer and that gene therapy with wild-type p53 or replication of viruses in p53 mutant cells may be important in the treatment of head and neck cancer.

Authors
Blobe, GC; Amrein, PC
MLA Citation
Blobe, GC, and Amrein, PC. "The p53 tumor suppressor gene in head and neck cancer." Current Opinion in Otolaryngology and Head and Neck Surgery 6.2 (1998): 129-133.
Source
scival
Published In
Current Opinion in Otolaryngology and Head and Neck Surgery
Volume
6
Issue
2
Publish Date
1998
Start Page
129
End Page
133
DOI
10.1097/00020840-199804000-00010

Protein kinase C beta II specifically binds to and is activated by F-actin (vol 271, pg 15823, 1996)

Authors
Blobe, GC; Stribling, DS; Fabbro, D; Stabel, S; Hannun, YA
MLA Citation
Blobe, GC, Stribling, DS, Fabbro, D, Stabel, S, and Hannun, YA. "Protein kinase C beta II specifically binds to and is activated by F-actin (vol 271, pg 15823, 1996)." JOURNAL OF BIOLOGICAL CHEMISTRY 271.47 (November 22, 1996): 30297-30297.
Source
wos-lite
Published In
The Journal of biological chemistry
Volume
271
Issue
47
Publish Date
1996
Start Page
30297
End Page
30297

Phosphorylation specificities of protein kinase C isozymes for bovine cardiac troponin I and troponin T and sites within these proteins and regulation of myofilament properties.

Protein kinase C (PKC) isozymes alpha, delta, epsilon, and zeta, shown to be expressed in adult rat cardiomyocytes, displayed distinct substrate specificities in phosphorylating troponin I and troponin T subunits in the bovine cardiac troponin complex. Thus, because they have different substrate affinities, PKC-alpha, -delta, and -epsilon phosphorylated troponin I more than troponin T, but PKC-zeta conversely phosphorylated the latter more than the former. Furthermore, PKC isozymes exhibited discrete specificities in phosphorylating distinct sites in these proteins as free subunits or in the troponin complex. Unlike other isozymes, PKC-delta was uniquely able to phosphorylate Ser-23/Ser-24 in troponin I, the bona fide phosphorylation sites for protein kinase A (PKA); and consequently, like PKA, it reduced Ca2+ sensitivity of Ca2+-stimulated MgATPase of reconstituted actomyosin S-1. In addition, PKC-delta, like PKC-alpha, readily phosphorylated Ser-43/Ser-45 (sites common for all PKC isozymes) and reduced maximal activity of MgATPase. In this respect, PKC-delta functioned as a hybrid of PKC-alpha and PKA. In contrast to PKC-alpha, -delta, and -epsilon, PKC-zeta exclusively phosphorylated two previously unknown sites in troponin T. Phosphorylation of troponin T by PKC-alpha resulted in decreases in both Ca2+ sensitivity and maximal activity, whereas phosphorylation by PKC-zeta resulted in a slight increase of the Ca2+ sensitivity without affecting the maximal activity of MgATPase. Most of the in vitro phosphorylation sites in troponin I and troponin T were confirmed in situ in adult rat cardiomyocytes. The present study has demonstrated for the first time distinct specificities of PKC isozymes for phosphorylation of two physiological substrates in the myocardium, with functional consequences.

Authors
Jideama, NM; Noland, TA; Raynor, RL; Blobe, GC; Fabbro, D; Kazanietz, MG; Blumberg, PM; Hannun, YA; Kuo, JF
MLA Citation
Jideama, NM, Noland, TA, Raynor, RL, Blobe, GC, Fabbro, D, Kazanietz, MG, Blumberg, PM, Hannun, YA, and Kuo, JF. "Phosphorylation specificities of protein kinase C isozymes for bovine cardiac troponin I and troponin T and sites within these proteins and regulation of myofilament properties." J Biol Chem 271.38 (September 20, 1996): 23277-23283.
PMID
8798526
Source
pubmed
Published In
The Journal of biological chemistry
Volume
271
Issue
38
Publish Date
1996
Start Page
23277
End Page
23283

Protein kinase C beta II specifically binds to and is activated by F-actin.

The two most closely related isoenzymes of protein kinase C (PKC), PKC betaI and betaII, are distinct but highly homologous isoenzymes derived via alternative splicing of the same gene product. In this study, PKC betaII, but not PKC betaI, translocated to the actin cytoskeleton upon stimulation of cells with phorbol esters. In cells, antibodies to PKC betaII, but not to PKC betaI, co-immunoprecipitated actin. Using an actin-binding co-sedimentation assay, we show in vitro that PKC betaII, but not PKC betaI, binds to actin specifically. This binding was inhibited by peptides based on sequences unique to PKC betaII; thus defining an actin-binding site in PKC betaII that is not present in PKC betaI. The binding of PKC betaII to actin was not inhibited by kinase inhibitors of PKC (sphingosine and staurosporine), suggesting that prior activation and/or substrate phosphorylation are not required for the interaction of PKC betaII with actin. On the other hand, the interaction of PKC betaII with actin resulted in marked enhancement of autophosphorylation of PKC betaII and in an alteration in substrate specificity. These studies serve to define a novel functional domain in the carboxyl-terminal region of PKC beta, which is involved in directing isoenzyme-specific protein-protein interactions, and consequently, isoenzyme-specific functions in vivo.

Authors
Blobe, GC; Stribling, DS; Fabbro, D; Stabel, S; Hannun, YA
MLA Citation
Blobe, GC, Stribling, DS, Fabbro, D, Stabel, S, and Hannun, YA. "Protein kinase C beta II specifically binds to and is activated by F-actin." J Biol Chem 271.26 (June 28, 1996): 15823-15830.
PMID
8663149
Source
pubmed
Published In
The Journal of biological chemistry
Volume
271
Issue
26
Publish Date
1996
Start Page
15823
End Page
15830

Protein kinase C isoenzymes: regulation and function.

PKC is composed of an ever growing family of lipid dependent serine/threonine protein kinases. Collectively, these isoenzymes are known to mediate critical roles in signal transduction, tumour promotion and cell regulation. PKCs appear to function as switches in acute signal transduction paradigms as well as rheostats in long term cell regulation with multiple mechanisms operating in the regulation of these functions. Although these roles of PKC are well established, little is known about the regulation and roles of individual isoenzymes of PKC in vitro or in vivo.

Authors
Blobe, GC; Stribling, S; Obeid, LM; Hannun, YA
MLA Citation
Blobe, GC, Stribling, S, Obeid, LM, and Hannun, YA. "Protein kinase C isoenzymes: regulation and function." Cancer Surv 27 (1996): 213-248. (Review)
PMID
8909803
Source
pubmed
Published In
Cancer surveys
Volume
27
Publish Date
1996
Start Page
213
End Page
248

Erratum: Protein kinase C βII specifically binds to and is activated by F-actin (Journal of Biological Chemistry (1996) 271 (15823-15830))

Authors
Blobe, GC; Stribling, DS; Fabbro, D; Stabel, S; Hannun, YA
MLA Citation
Blobe, GC, Stribling, DS, Fabbro, D, Stabel, S, and Hannun, YA. "Erratum: Protein kinase C βII specifically binds to and is activated by F-actin (Journal of Biological Chemistry (1996) 271 (15823-15830))." Journal of Biological Chemistry 271.47 (1996): 30297--.
Source
scival
Published In
Journal of Biological Chemistry
Volume
271
Issue
47
Publish Date
1996
Start Page
30297-

Arachidonic acid and free fatty acids as second messengers and the role of protein kinase C.

In addition to serving as the precursor to a plethora of eicosanoids and other bioactive molecules, arachidonate may function as a bona fide second messenger. A number of studies have documented the ability of arachidonate to regulate the function of multiple targets in vitro systems. This has been particularly well established and studied with the activation of protein kinase C by arachidonate in a mechanism distinct from activation by diacylglycerol. In cells, arachidonate induces a number of activities, many of which may be independent of further metabolism to eicosanoids; suggesting possible direct action of arachidonate. This review summarizes the current state of knowledge on the possible second messenger function of arachidonate with specific emphasis on the regulation of protein kinase C.

Authors
Khan, WA; Blobe, GC; Hannun, YA
MLA Citation
Khan, WA, Blobe, GC, and Hannun, YA. "Arachidonic acid and free fatty acids as second messengers and the role of protein kinase C." Cell Signal 7.3 (March 1995): 171-184. (Review)
PMID
7662506
Source
pubmed
Published In
Cellular Signalling
Volume
7
Issue
3
Publish Date
1995
Start Page
171
End Page
184

Protein kinase C: cellular target of the second messenger arachidonic acid?

Authors
Blobe, GC; Khan, WA; Hannun, YA
MLA Citation
Blobe, GC, Khan, WA, and Hannun, YA. "Protein kinase C: cellular target of the second messenger arachidonic acid?." Prostaglandins Leukot Essent Fatty Acids 52.2-3 (February 1995): 129-135. (Review)
PMID
7784448
Source
pubmed
Published In
PLEFA - Prostaglandins, Leukotrienes & Essential Fatty Acids
Volume
52
Issue
2-3
Publish Date
1995
Start Page
129
End Page
135

Regulation of protein kinase C and role in cancer biology.

Protein kinase C (PKC) is a family of closely related lipid-dependent and diacyglycerol-activated isoenzymes known to play an important role in the signal transduction pathways involved in hormone release, mitogenesis and tumor promotion. Reversible activation of PKC by the second messengers diacylglycerol and calcium is an established model for the short term regulation of PKC in the immediate events of signal transduction. PKC can also be modulated long term by changes in the levels of activators or inhibitors for a prolonged period or by changes in the levels of functional PKC isoenzymes in the cell during development or in response to hormones and/or differentiation factors. Indeed, studies have indicated that the sustained activation or inhibition of PKC activity in vivo may play a critical role in regulation of long term cellular events such as proliferation, differentiation and tumorigenesis. In addition, these regulatory events are important in colon cancer, where a decrease in PKC activators and activity suggests PKC acts as an anti-oncogene, in breast cancer, where an increase in PKC activity suggests an oncogenic role for PKC, and in multidrug resistance (MDR) and metastasis where an increase in PKC activity correlates with increased resistance and metastatic potential. These studies highlight the importance and significance of regulation of PKC activity in vivo.

Authors
Blobe, GC; Obeid, LM; Hannun, YA
MLA Citation
Blobe, GC, Obeid, LM, and Hannun, YA. "Regulation of protein kinase C and role in cancer biology." Cancer Metastasis Rev 13.3-4 (December 1994): 411-431. (Review)
PMID
7712599
Source
pubmed
Published In
Cancer and Metastasis Reviews
Volume
13
Issue
3-4
Publish Date
1994
Start Page
411
End Page
431

Identification of a defect in the phospholipase D/diacylglycerol pathway in cellular senescence.

Normal cells become senescent in culture after a limited number of population doublings becoming unable to respond to mitogens. This raises the possibility of defects in mitogenic signaling pathways in cellular senescence. In contrast to young human diploid fibroblasts (HDF), their senescent counterparts failed to undergo protein kinase C translocation in response to serum stimulation. On the other hand, phorbol 12-myristate 13-acetate was equally active in inducing protein kinase C translocation in young and senescent HDF. This suggested a defect in generation of the endogenous activator of protein kinase C, diacylglycerol. Stimulation of young HDF with serum resulted in 3-4-fold generation of diacylglycerol (DAG). In contrast, senescent cells displayed insignificant DAG formation in response to serum. The mechanism of DAG generation was investigated next. In young HDF, serum induced a 5-fold activation of the phospholipase D (PLD) pathway as measured by the incorporation of exogenous ethanol into phosphatidylethanol, which is a measure of the transphosphatidylation reaction of PLD. In contrast, PLD in senescent cells was not activated by serum. Since senescent cells demonstrate significant elevations in the level of endogenous ceramide, the impact of ceramide on the PLD/DAG pathway was also investigated. A soluble analog of ceramide, C6-ceramide, was found to inhibit serum-stimulated DAG accumulation and PLD activation in young cells. These data demonstrate for the first time a defect in PLD activation in cellular senescence and suggest that ceramide may be responsible for the inhibition of this pathway.

Authors
Venable, ME; Blobe, GC; Obeid, LM
MLA Citation
Venable, ME, Blobe, GC, and Obeid, LM. "Identification of a defect in the phospholipase D/diacylglycerol pathway in cellular senescence." J Biol Chem 269.42 (October 21, 1994): 26040-26044.
PMID
7929315
Source
pubmed
Published In
The Journal of biological chemistry
Volume
269
Issue
42
Publish Date
1994
Start Page
26040
End Page
26044

Identification, partial purification, and characterization of a novel phospholipid-dependent and fatty acid-activated protein kinase from human platelets.

A novel lipid-dependent protein kinase in human platelets was partially purified and characterized. This enzyme was calcium-independent and was selective for phosphatidic acid as a cofactor/activator with initial activation observed at approximately 2 mol % and peak activity achieved at 4 mol % phosphatidic acid. In the presence of phosphatidylserine, enzyme activation was observed with concentrations of phosphatidic acid as low as 0.5 mol % with peak activity at 2 mol %. Other anionic phospholipids also activated the enzyme but to a lesser extent and with less potency. Enzyme activity was independent of diacylglycerol or phorbol esters and the enzyme did not bind [3H]phorbol dibutyrate. In a soluble protein kinase assay, the enzyme was activated by cis-unsaturated fatty acids with maximum activation occurring at 5-10 microM sodium oleate. Western blot analysis showed that this enzyme did not cross-react immunologically with antibodies raised against the currently identified isoenzymes of protein kinase C. A number of additional biochemical criteria distinguished this enzyme from known isoenzymes of protein kinase C. These biochemical and immunologic data define a novel lipid-dependent protein kinase in human platelets. The role of this enzyme in signal transduction as a phosphatidic acid-activated enzyme and as a possible target for cis-unsaturated fatty acids is discussed.

Authors
Khan, WA; Blobe, GC; Richards, AL; Hannun, YA
MLA Citation
Khan, WA, Blobe, GC, Richards, AL, and Hannun, YA. "Identification, partial purification, and characterization of a novel phospholipid-dependent and fatty acid-activated protein kinase from human platelets." J Biol Chem 269.13 (April 1, 1994): 9729-9735.
PMID
8144564
Source
pubmed
Published In
The Journal of biological chemistry
Volume
269
Issue
13
Publish Date
1994
Start Page
9729
End Page
9735

Specific role for protein kinase C beta in cell differentiation.

A critical role for protein kinase C (PKC) in signal transduction events has been well established. On the other hand, emerging evidence also suggests a role for regulation of PKC levels in mediating long term cellular functions. In human leukemia cell line HL-60, the action of 1,25-dihydroxyvitamin D3 results in transcriptional up-regulation of PKC beta (within 8-12 h) (L. M. Obeid et al., J. Biol. Chem., 265: 2370-2374, 1990). In this study, the role of PKC beta in the regulation of proliferation and differentiation was studied. 1,25-Dihydroxyvitamin D3 caused an increase in PKC beta I, beta II, and, to a lesser extent, PKC alpha, as determined by Western blot analysis. This increase was accompanied by inhibition of proliferation and induction of differentiation. The addition of a 25-base pair antisense oligonucleotide directed against the 5' coding sequence of PKC beta attenuated up-regulation of PKC beta I and beta II levels in response to 1,25-dihydroxyvitamin D3. This antisense oligonucleotide, but not sense oligonucleotide or antisense oligonucleotide to PKC alpha, caused inhibition of 1,25-dihydroxyvitamin D3-induced differentiation by 25-45%. On the other hand, inhibition of cell proliferation by 1,25-dihydroxyvitamin D3 was minimally affected by the addition of antisense oligonucleotides. These results identify a role for PKC beta in cell differentiation and underscore the significance of transcriptional activation of PKC as a mechanism for long-term regulation of PKC. The results also distinguish signaling pathways involved in cell differentiation from those involved in antiproliferation.

Authors
Gamard, CJ; Blobe, GC; Hannun, YA; Obeid, LM
MLA Citation
Gamard, CJ, Blobe, GC, Hannun, YA, and Obeid, LM. "Specific role for protein kinase C beta in cell differentiation." Cell Growth Differ 5.4 (April 1994): 405-409.
PMID
8043514
Source
pubmed
Published In
Cell growth & differentiation : the molecular biology journal of the American Association for Cancer Research
Volume
5
Issue
4
Publish Date
1994
Start Page
405
End Page
409

DETERMINATION OF A NEW FUNCTIONAL DOMAIN FOR PROTEIN-KINASE-C WHICH DIRECTS ISOENZYME SPECIFIC PROTEIN-PROTEIN INTERACTIONS

Authors
BLOBE, GC; HANNUN, YA
MLA Citation
BLOBE, GC, and HANNUN, YA. "DETERMINATION OF A NEW FUNCTIONAL DOMAIN FOR PROTEIN-KINASE-C WHICH DIRECTS ISOENZYME SPECIFIC PROTEIN-PROTEIN INTERACTIONS." CLINICAL RESEARCH 42.2 (April 1994): A114-A114.
Source
wos-lite
Published In
Clinical Research
Volume
42
Issue
2
Publish Date
1994
Start Page
A114
End Page
A114

A NOVEL CALCIUM-INDEPENDENT AND PHOSPHATIDIC ACID-ACTIVATED PROTEIN-KINASE DISCOVERED IN HUMAN PLATELETS

Authors
RICHARDS, AL; KHAN, WA; BLOBE, GC; HANNUN, YA
MLA Citation
RICHARDS, AL, KHAN, WA, BLOBE, GC, and HANNUN, YA. "A NOVEL CALCIUM-INDEPENDENT AND PHOSPHATIDIC ACID-ACTIVATED PROTEIN-KINASE DISCOVERED IN HUMAN PLATELETS." CLINICAL RESEARCH 42.2 (April 1994): A114-A114.
Source
wos-lite
Published In
Clinical Research
Volume
42
Issue
2
Publish Date
1994
Start Page
A114
End Page
A114

Regulation of protein kinase C and role in cancer biology

Authors
BLOBE, G
MLA Citation
BLOBE, G. "Regulation of protein kinase C and role in cancer biology." Cancer Metastasis Rev. 13 (1994): 411-431.
Source
cinii-english
Published In
Cancer Metastasis Rev.
Volume
13
Publish Date
1994
Start Page
411
End Page
431
DOI
10.1007/BF00666107

IDENTIFICATION OF SEQUENCE-SPECIFIC INTERACTIONS OF PROTEIN-KINASE-C ISOENZYMES WITH THE ACTIN CYTOSKELETON

Authors
BLOBE, GC; FABBRO, D; STABEL, S; HANNUN, YA
MLA Citation
BLOBE, GC, FABBRO, D, STABEL, S, and HANNUN, YA. "IDENTIFICATION OF SEQUENCE-SPECIFIC INTERACTIONS OF PROTEIN-KINASE-C ISOENZYMES WITH THE ACTIN CYTOSKELETON." JOURNAL OF CELLULAR BIOCHEMISTRY (1994): 81-81.
Source
wos-lite
Published In
Journal of Cellular Biochemistry
Publish Date
1994
Start Page
81
End Page
81

Selective regulation of expression of protein kinase C beta isoenzymes occurs via alternative splicing.

The mechanisms involved in regulating the selective expression of protein kinase C (PKC) isoenzymes are poorly understood. Two human B lymphoblastoid cell lines, IM-9 and BJA-B, exhibited differential expression of the two alternatively spliced products of the PKC beta gene, PKC beta I and beta II. The IM-9 cell line expressed 3-4-fold more PKC beta II protein than the BJA-B cell line, whereas the BJA-B cell line expressed 2-3-fold more PKC beta I protein. This differential expression was found to be regulated at the mRNA level. Comparison of PKC beta I and beta II messages in poly(A)+ mRNA and total cellular RNA revealed that selective polyadenylation was not involved. The messages for PKC beta I and beta II had comparable half-lives in both cell lines, ruling out differential message stability. In addition, similar ratios of PKC beta I and beta II messages in cytosolic and nuclear fractions suggested that differential mRNA transport was not involved. In the IM-9 cell line, the predominance of mature PKC beta II message as well as that of a larger message spliced to PKC beta II provided evidence that the differential expression of PKC beta II was regulated at the level of mRNA splicing. In the BJA-B cell line, equal amounts of mature PKC beta I and beta II message and the absence of the larger message suggested that the splicing of the PKC beta gene product can be regulated to produce altered ratios of PKC beta I and beta II. Implications of these studies on the differential expression of PKC isoenzymes and their roles in biology are discussed.

Authors
Blobe, GC; Khan, WA; Halpern, AE; Obeid, LM; Hannun, YA
MLA Citation
Blobe, GC, Khan, WA, Halpern, AE, Obeid, LM, and Hannun, YA. "Selective regulation of expression of protein kinase C beta isoenzymes occurs via alternative splicing." J Biol Chem 268.14 (May 15, 1993): 10627-10635.
PMID
7683684
Source
pubmed
Published In
The Journal of biological chemistry
Volume
268
Issue
14
Publish Date
1993
Start Page
10627
End Page
10635

DETERMINATION OF THE FUNCTIONAL DIFFERENCES BETWEEN PROTEIN-KINASE-C BETA(1) AND BETA(II) ISOENZYMES

Authors
BLOBE, GC; FABBRO, D; HANNUN, YA
MLA Citation
BLOBE, GC, FABBRO, D, and HANNUN, YA. "DETERMINATION OF THE FUNCTIONAL DIFFERENCES BETWEEN PROTEIN-KINASE-C BETA(1) AND BETA(II) ISOENZYMES." FASEB JOURNAL 7.7 (April 20, 1993): A1119-A1119.
Source
wos-lite
Published In
The FASEB journal : official publication of the Federation of American Societies for Experimental Biology
Volume
7
Issue
7
Publish Date
1993
Start Page
A1119
End Page
A1119

SELECTIVE TRANSLOCATION OF PROTEIN-KINASE-C BETA-I AND BETA-II ISOENZYMES TO THE CYTOSKELETON

Authors
BLOBE, GC; FABBRO, D; OBEID, LM; HANNUN, YA
MLA Citation
BLOBE, GC, FABBRO, D, OBEID, LM, and HANNUN, YA. "SELECTIVE TRANSLOCATION OF PROTEIN-KINASE-C BETA-I AND BETA-II ISOENZYMES TO THE CYTOSKELETON." CLINICAL RESEARCH 41.2 (April 1993): A242-A242.
Source
wos-lite
Published In
Clinical Research
Volume
41
Issue
2
Publish Date
1993
Start Page
A242
End Page
A242

Selective regulation of protein kinase C isoenzymes by oleic acid in human platelets.

Cis-unsaturated fatty acids activate soluble protein kinase C (PKC) in vitro and in intact platelets. The following studies were conducted to determine the effects of oleate on individual isoenzymes of PKC in human platelets. Human platelets were found to contain predominantly PKC alpha, beta I, beta II, and delta with minor immunoreactivity for PKC epsilon, zeta, and eta. In intact platelets, sodium oleate caused a time-dependent redistribution of PKC alpha, beta II, and delta from cytosol to membrane fractions with little effects on PKC beta I. On the other hand, PMA and thrombin induced translocation of all four isoenzymes of PKC. In vitro, oleate partially activated (50% of Vmax) purified calcium-dependent PKC (alpha, beta I, and beta II) with an EC50 of 50 microM whereas it fully activated (100% of Vmax) purified calcium-independent PKC (predominantly delta) with an EC50 of 5 microM. The selective effects of oleate on PKC isoenzymes were investigated in platelet cytosol which contains endogenous PKC and its physiologic substrates. Under these conditions, oleate potently activated calcium-independent PKC causing the phosphorylation of the 40-kDa substrate. Activation of calcium-dependent isoforms occurred only at higher concentrations of oleate. Thus, oleate activates multiple isoenzymes of PKC with predominant effects on calcium-independent PKC.

Authors
Khan, WA; Blobe, G; Halpern, A; Taylor, W; Wetsel, WC; Burns, D; Loomis, C; Hannun, YA
MLA Citation
Khan, WA, Blobe, G, Halpern, A, Taylor, W, Wetsel, WC, Burns, D, Loomis, C, and Hannun, YA. "Selective regulation of protein kinase C isoenzymes by oleic acid in human platelets." J Biol Chem 268.7 (March 5, 1993): 5063-5068.
PMID
8444883
Source
pubmed
Published In
The Journal of biological chemistry
Volume
268
Issue
7
Publish Date
1993
Start Page
5063
End Page
5068

Selective regulation of expression of protein kinase C (PKC) isoenzymes in multidrug-resistant MCF-7 cells. Functional significance of enhanced expression of PKC alpha.

The multidrug resistance (MDR) phenotype induces cross-resistance to many chemotherapeutic agents in cancer cells. Protein kinase C (PKC) has been implicated in the regulation of the MDR phenotype. In order to determine the role of specific PKC isoenzymes in regulating the MDR phenotype, the expression and activity of PKC isoenzymes in the human breast cancer cell line, MCF-7-WT, and an MDR subline, MCF-7-MDR, were examined. The MDR phenotype was associated with a 10-fold increase in calcium-dependent PKC activity as well as a 10-fold decrease in calcium-independent activity was due to a selective increase in the activity was due to a selective increase in the expression of PKC alpha as determined by Western blot analysis and hydroxylapatite chromatography. This increase in expression of PKC alpha was regulated at the message level as demonstrated by Northern blot analysis. The decrease in calcium-independent activity was caused by a decrease in the expression of PCK delta and epsilon. The significance of the increase in PKC alpha expression was then demonstrated by a commensurate 11-fold increase in the basal and stimulated phosphorylation of the myristolated alanine-rich C kinase substrate. Phosphorylation of P-glycoprotein, the cellular mediator of the MDR phenotype, was increased > 20-fold in the unstimulated MCF-7-MDR cell line and its phosphorylation was further increased 2-fold in response to phorbol 12-myristate 13-acetate. These changes paralleled the increases in P-glycoprotein pump function and the MDR phenotype underscoring the role for PKC alpha in regulating P-glycoprotein phosphorylation and function.

Authors
Blobe, GC; Sachs, CW; Khan, WA; Fabbro, D; Stabel, S; Wetsel, WC; Obeid, LM; Fine, RL; Hannun, YA
MLA Citation
Blobe, GC, Sachs, CW, Khan, WA, Fabbro, D, Stabel, S, Wetsel, WC, Obeid, LM, Fine, RL, and Hannun, YA. "Selective regulation of expression of protein kinase C (PKC) isoenzymes in multidrug-resistant MCF-7 cells. Functional significance of enhanced expression of PKC alpha." J Biol Chem 268.1 (January 5, 1993): 658-664.
PMID
8093247
Source
pubmed
Published In
The Journal of biological chemistry
Volume
268
Issue
1
Publish Date
1993
Start Page
658
End Page
664

Cloning and characterization of the major promoter of the human protein kinase C beta gene. Regulation by phorbol esters.

The expression of the beta isoenzyme for protein kinase C is regulated developmentally and in response to inducers of cell differentiation (such as phorbol esters and 1 alpha,25-dihydroxyvitamin D3). The 5' segment of the gene for protein kinase C beta was cloned from a human leukocyte genomic library in EMBL3 bacteriophage. This segment of the gene (greater than 54 kilobases in length) encompassed the coding sequence for the amino-terminal regulatory domain of the enzyme, the 5'-untranslated region, and the 5'-flanking region. Initiation of transcription was identified by S1 nuclease analysis and confirmed by RNase protection analysis at 197 base pairs 5' of the initiator ATG. Sequence analysis of the 5'-flanking region revealed it to be extremely G+C-rich (> 80%) with many features of a CpG island. Comparison of sequence with known cis-regulatory motifs disclosed a number of potential regulatory elements including an octamer binding motif at -76, Sp1-binding sites at -94 and -63, E boxes at -110, -26, and +18, an AP-1 site at -442, and an AP-2 site at -330. To demonstrate promoter activity, a 630-base pair fragment extending from -587 to +43 was subcloned in front of a promoterless luciferase gene. This fragment was able to drive the expression of luciferase in transient transfections of human hematopoietic cells. Deletion analysis demonstrated that a fragment -111 to +43 was necessary and sufficient for promoter activity; this fragment did not contain TATA or CAAT motifs. The promoter was stimulated 8-20-fold by phorbol esters accounting for the previously observed transcriptional activation of protein kinase C beta. This phorbol ester responsiveness was conferred by the basal promoter (-111 to +43) and was independent of the AP-1 site. These results define a novel mechanism of protein kinase C autoregulation at a transcriptional level.

Authors
Obeid, LM; Blobe, GC; Karolak, LA; Hannun, YA
MLA Citation
Obeid, LM, Blobe, GC, Karolak, LA, and Hannun, YA. "Cloning and characterization of the major promoter of the human protein kinase C beta gene. Regulation by phorbol esters." J Biol Chem 267.29 (October 15, 1992): 20804-20810.
PMID
1400396
Source
pubmed
Published In
The Journal of biological chemistry
Volume
267
Issue
29
Publish Date
1992
Start Page
20804
End Page
20810

SELECTIVE REGULATION OF ALTERNATIVELY SPLICED PROTEIN-KINASE-C ISOENZYMES

Authors
BLOBE, GC; HALPERN, AE; HANNUN, YA; OBEID, LM
MLA Citation
BLOBE, GC, HALPERN, AE, HANNUN, YA, and OBEID, LM. "SELECTIVE REGULATION OF ALTERNATIVELY SPLICED PROTEIN-KINASE-C ISOENZYMES." CLINICAL RESEARCH 40.2 (April 1992): A243-A243.
Source
wos-lite
Published In
Clinical Research
Volume
40
Issue
2
Publish Date
1992
Start Page
A243
End Page
A243

A ROLE FOR SPECIFIC PROTEIN-KINASE-C ISOENZYMES IN MODULATING THE MULTIDRUG RESISTANT PHENOTYPE

Authors
BLOBE, GC; KHAN, WA; WETSEL, WC; OBEID, LM; FINE, RL; HANNUN, YA
MLA Citation
BLOBE, GC, KHAN, WA, WETSEL, WC, OBEID, LM, FINE, RL, and HANNUN, YA. "A ROLE FOR SPECIFIC PROTEIN-KINASE-C ISOENZYMES IN MODULATING THE MULTIDRUG RESISTANT PHENOTYPE." CLINICAL RESEARCH 40.2 (April 1992): A375-A375.
Source
wos-lite
Published In
Clinical Research
Volume
40
Issue
2
Publish Date
1992
Start Page
A375
End Page
A375

Activation of protein kinase C by oleic acid. Determination and analysis of inhibition by detergent micelles and physiologic membranes: requirement for free oleate.

Sodium oleate is able to activate soluble protein kinase C (Murakami, K., Chan, S. Y., and Routtenberg, A. (1986) J. Biol. Chem. 261, 15424-15429) but is unable to activate membrane-bound enzyme (El Touny, S., Khan, W., and Hannun, Y. (1990) J. Biol. Chem. 265, 16437-16443). Because physiologic interactions of fatty acids with protein kinase C occur in the presence of membranes, the following studies were conducted to evaluate the effects of surfaces (detergent micelles or platelet membranes) on the activation of protein kinase C by oleate. At concentrations at or above the critical micellar concentration (CMC) of Triton X-100, oleate was present primarily in Triton X-100/oleate-mixed micelles, as determined by gel permeation chromatography and equilibrium dialysis binding studies. At concentrations slightly below the CMC for Triton X-100, the presence of oleate caused the formation of a limited number of mixed micelles. Studies of the dose-dependent activation of purified platelet protein kinase C by sodium oleate in the presence of different concentrations of Triton X-100 indicated that only unbound oleate was able to activate protein kinase C. Platelet protein kinase C was resolved into two major isoenzymes (types II (beta) and III (alpha)) which displayed nearly identical interaction with oleate. Activation of protein kinase C by oleate in a physiologic setting employing platelet substrates and endogenous platelet protein kinase C was investigated. Oleate potently activated protein kinase C in the cytosolic compartment. In platelet homogenates as well as in a reconstituted platelet cytosol and membrane system, the dose dependence of protein kinase C on oleate showed a significant shift to the right. Approximately 30% of oleate was associated with platelet cytosol and 70% was associated with platelet membranes. Partitioning of oleate into the two platelet compartments showed little change with pH, temperature, or duration of incubation. When corrected for free oleate concentration, activation of protein kinase C by oleate showed identical dose dependence in cytosol and homogenate. Arachidonate, a potential physiologic activator of protein kinase C, showed similar behavior as oleate although only 30% of arachidonate partitioned into platelet membranes with the majority of arachidonate (70%) remaining in the cytosolic fraction.(ABSTRACT TRUNCATED AT 400 WORDS)

Authors
Khan, WA; Blobe, GC; Hannun, YA
MLA Citation
Khan, WA, Blobe, GC, and Hannun, YA. "Activation of protein kinase C by oleic acid. Determination and analysis of inhibition by detergent micelles and physiologic membranes: requirement for free oleate." J Biol Chem 267.6 (February 25, 1992): 3605-3612.
PMID
1740412
Source
pubmed
Published In
The Journal of biological chemistry
Volume
267
Issue
6
Publish Date
1992
Start Page
3605
End Page
3612

Conformational studies of the nucleic acid binding sites for Xenopus transcription factor IIIA.

The CD spectrum of a restriction fragment that contains a single copy of a Xenopus borealis somatic 5 S rRNA gene, like those of two smaller fragments from the binding site for transcription factor IIIA (TFIIIA), is that of B-form DNA. Under dehydrating conditions (76% ethanol) the 5 S rDNA undergoes a transition into an A conformation. The spectra of the three fragments, however, do exhibit some perturbation in that the longwave positive peaks are shifted to shorter wavelengths and have enhanced rotational strength compared with reference B-form spectra. The helical repeats measured for the smaller fragments indicate that the helix winding angle can account for these features in the CD spectra. We suggest that G:C-rich boxes that punctuate not only the TFIIIA binding site but the whole 5 S gene are responsible for the conformational perturbation manifest in the CD spectra and may play a role in the recognition of the DNA by the factor. The spectrum of the gene is unchanged in the presence of TFIIIA, indicating that the structural heterogeneity of the DNA persists upon complex formation. The CD spectra of native TFIIIA.5 S rRNA particles isolated from oocytes and of particles reconstituted in vitro are identical and only moderately different from the spectrum of free 5 S rRNA, suggesting that the protein effects only limited changes in the secondary and/or tertiary structure of the RNA. The helical structure of the two binding sites is discussed with respect to a common mode of interaction of TFIIIA with DNA and RNA.

Authors
Huber, PW; Blobe, GC; Hartmann, KM
MLA Citation
Huber, PW, Blobe, GC, and Hartmann, KM. "Conformational studies of the nucleic acid binding sites for Xenopus transcription factor IIIA." J Biol Chem 266.5 (February 15, 1991): 3278-3286.
PMID
1993700
Source
pubmed
Published In
The Journal of biological chemistry
Volume
266
Issue
5
Publish Date
1991
Start Page
3278
End Page
3286
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