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Linardic, Corinne Mary

Overview:

Pediatric Sarcomas: Sarcomas are among the most difficult-to-treat cancers in pediatric oncology, with metastatic forms having the highest mortality. We have established genetically defined human cell-based models for the pediatric skeletal muscle cancer known as rhabdomyosarcoma. Current therapies are based on xenograft models in immunocompromised mice, using established patient-derived patient cell lines, but because of the genetic variability of these cell lines, a true understanding of the causative role of certain genetic changes (e.g. chromosomal translocations and oncogenic Ras) in rhabdomyosarcoma formation is not understood. Specific goals of this research program include the identification of signaling pathways corrupted in rhabdomyosarcoma, with focus on the PAX3-FOXO1 mutation and its downstream effectors and oncogenic Ras, and identification of new therapeutic targets for treatment of this childhood cancer.

Positions:

Associate Professor of Pediatrics

Pediatrics, Hematology-Oncology
School of Medicine

Associate 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:

Ph.D. 1993

Ph.D. — Duke University

M.D. 1995

M.D. — Duke University

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

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

Targeting the Hippo pathway in Ras-driven rhabdomyosarcoma

Administered By
Pediatrics, Hematology-Oncology
AwardedBy
V Foundation for Cancer Research
Role
Principal Investigator
Start Date
November 01, 2016
End Date
October 31, 2019

The role of MST1 in non-canonical Hippo signaling in rhabdomyosarcoma

Administered By
Pediatrics, Hematology-Oncology
AwardedBy
Alex's Lemonade Stand
Role
Principal Investigator
Start Date
January 15, 2015
End Date
January 14, 2018

St. Baldrick's Summer Fellow Grant

Administered By
Pediatrics, Hematology-Oncology
AwardedBy
St. Baldrick's Foundation
Role
Co-Principal Investigator
Start Date
May 15, 2017
End Date
July 07, 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

A Novel Hippo-Notch axis controlling embryonal rhabdomyosarcoma tumorigenesis

Administered By
Pediatrics, Hematology-Oncology
AwardedBy
V Foundation for Cancer Research
Role
Principal Investigator
Start Date
June 15, 2016
End Date
June 15, 2017

The role of MEST (mesoderm specific transcript) in rhabdomyosarcoma

Administered By
Pediatrics, Hematology-Oncology
AwardedBy
St. Baldrick's Foundation
Role
Principal Investigator
Start Date
July 01, 2015
End Date
December 31, 2016

Validating a mouse model of rhabdomyosarcoma

Administered By
Pediatrics, Hematology-Oncology
AwardedBy
Alex's Lemonade Stand
Role
Principal Investigator
Start Date
May 16, 2016
End Date
July 08, 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

The secreted protein SFRP3 as a therapeutic target in rhabdomyosarcoma

Administered By
Pediatrics, Hematology-Oncology
AwardedBy
V Foundation for Cancer Research
Role
Principal Investigator
Start Date
February 01, 2015
End Date
January 31, 2016

Feasibility of a Couple-based Intervention for Parents of Children with Cancer

Administered By
Psychiatry & Behavioral Sciences, Behavioral Medicine
AwardedBy
National Institutes of Health
Role
Co Investigator
Start Date
July 09, 2012
End Date
December 31, 2014

Molecular Modeling of Pediatric Skeletal Muscle Tumors

Administered By
Pediatrics, Hematology-Oncology
AwardedBy
National Institutes of Health
Role
Principal Investigator
Start Date
January 01, 2009
End Date
November 30, 2013
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Publications:

Recent Insights into Notch Signaling in Embryonal Rhabdomyosarcoma.

The Notch signaling pathway is an evolutionarily conserved developmental network critical for embryonic and postnatal regulation of tissue growth, homeostasis, and repair. Signaling is initiated when transmembrane Notch ligands bind to transmembrane Notch receptors on nearby cells. Sequential proteolytic steps generate an activated Notch fragment that translocates to the nucleus, where it drives activation of canonical Notch target genes. In skeletal muscle, Notch signaling governs myogenic cell fate and stem cell maintenance. In the human soft tissue sarcoma rhabdomyosarcoma, which bears markers of skeletal muscle commitment and so is thought to be related to the skeletal muscle lineage, Notch signaling is also found to be upregulated and dysregulated. This review provides an overview of Notch signaling during normal embryonic and postnatal myogenesis, information on the recently discovered aberrant Notch signaling occurring in muscular dystrophies, the upregulation and mechanism of Notch signaling in the embryonal variant of rhabdomyosarcoma and related soft tissue sarcomas, and Notch cross-talk with other metazoan developmental pathways including Hippo, Hedgehog, Wnt, and TGF-β. The review concludes with updates on current promising efforts to target and inhibit Notch signaling in human sarcomas including rhabdomyosarcoma.

Authors
Conti, B; Slemmons, KK; Rota, R; Linardic, CM
MLA Citation
Conti, B, Slemmons, KK, Rota, R, and Linardic, CM. "Recent Insights into Notch Signaling in Embryonal Rhabdomyosarcoma." Current drug targets 17.11 (January 2016): 1235-1244.
PMID
26343114
Source
epmc
Published In
Current Drug Targets
Volume
17
Issue
11
Publish Date
2016
Start Page
1235
End Page
1244
DOI
10.2174/1389450116666150907105756

Secreted Frizzled-Related Protein 3 (SFRP3) Is Required for Tumorigenesis of PAX3-FOXO1-Positive Alveolar Rhabdomyosarcoma.

Rhabdomyosarcoma (RMS) is a soft tissue sarcoma associated with the skeletal muscle lineage. Of the two predominant subtypes, known as embryonal (eRMS) and alveolar (aRMS), aRMS has the poorer prognosis, with a five-year survival rate of <50%. The majority of aRMS tumors express the fusion protein PAX3-FOXO1. As PAX3-FOXO1 has proven chemically intractable, this study aims to identify targetable proteins that are downstream from or cooperate with PAX3-FOXO1 to support tumorigenesis.Microarray analysis of the transcriptomes of human skeletal muscle myoblasts expressing PAX3-FOXO1 revealed alteration of several Wnt pathway gene members, including secreted frizzled related protein 3 (SFRP3), a secreted Wnt pathway inhibitor. Loss-of-function using shRNAs against SFRP3 was used to interrogate the role of SFRP3 in human aRMS cell lines in vitro and conditional murine xenograft systems in vivo. The combination of SFRP3 genetic suppression and the chemotherapeutic agent vincristine was also examined.In vitro, suppression of SFRP3 inhibited aRMS cell growth, reduced proliferation accompanied by a G1 arrest and induction of p21, and induced apoptosis. In vivo, doxycycline-inducible suppression of SFRP3 reduced aRMS tumor growth and weight by more than three-fold, in addition to increasing myogenic differentiation and β-catenin signaling. The combination of SFRP3 suppression and vincristine was more effective at reducing aRMS cell growth in vitro than either treatment alone, and ablated tumorigenesis in vivo.SFRP3 is necessary for the growth of human aRMS cells both in vitro and in vivo and is a promising new target for investigation in aRMS.

Authors
Kephart, JJG; Tiller, RGJ; Crose, LES; Slemmons, KK; Chen, P-H; Hinson, AR; Bentley, RC; Chi, J-TA; Linardic, CM
MLA Citation
Kephart, JJG, Tiller, RGJ, Crose, LES, Slemmons, KK, Chen, P-H, Hinson, AR, Bentley, RC, Chi, J-TA, and Linardic, CM. "Secreted Frizzled-Related Protein 3 (SFRP3) Is Required for Tumorigenesis of PAX3-FOXO1-Positive Alveolar Rhabdomyosarcoma." Clinical cancer research : an official journal of the American Association for Cancer Research 21.21 (November 2015): 4868-4880.
PMID
26071485
Source
epmc
Published In
Clinical cancer research : an official journal of the American Association for Cancer Research
Volume
21
Issue
21
Publish Date
2015
Start Page
4868
End Page
4880
DOI
10.1158/1078-0432.ccr-14-1797

Histone Deacetylase Inhibitors Inhibit Rhabdomyosarcoma by Reactive Oxygen Species-Dependent Targeting of Specificity Protein Transcription Factors.

The two major types of rhabdomyosarcoma (RMS) are predominantly diagnosed in children, namely embryonal (ERMS) and alveolar (ARMS) RMS, and patients are treated with cytotoxic drugs, which results in multiple toxic side effects later in life. Therefore, development of innovative chemotherapeutic strategies is imperative, and a recent genomic analysis suggested the potential efficacy of reactive oxygen species (ROS)-inducing agents. Here, we demonstrate the efficacy of the potent histone deacetylase (HDAC) inhibitors, panobinostat and vorinostat, as agents that inhibit RMS tumor growth in vivo, induce apoptosis, and inhibit invasion of RD and Rh30 RMS cell lines. These effects are due to epigenetic repression of cMyc, which leads to decreased expression of cMyc-regulated miRs-17, -20a, and -27a; upregulation of ZBTB4, ZBTB10, and ZBTB34; and subsequent downregulation of Sp transcription factors. We also show that inhibition of RMS cell growth, survival and invasion, and repression of Sp transcription factors by the HDAC inhibitors are independent of histone acetylation but reversible after cotreatment with the antioxidant glutathione. These results show a novel ROS-dependent mechanism of antineoplastic activity for panobinostat and vorinostat that lies outside of their canonical HDAC-inhibitory activity and demonstrates the potential clinical utility for treating RMS patients with ROS-inducing agents.

Authors
Hedrick, E; Crose, L; Linardic, CM; Safe, S
MLA Citation
Hedrick, E, Crose, L, Linardic, CM, and Safe, S. "Histone Deacetylase Inhibitors Inhibit Rhabdomyosarcoma by Reactive Oxygen Species-Dependent Targeting of Specificity Protein Transcription Factors." Molecular cancer therapeutics 14.9 (September 2015): 2143-2153.
PMID
26162688
Source
epmc
Published In
Molecular cancer therapeutics
Volume
14
Issue
9
Publish Date
2015
Start Page
2143
End Page
2153
DOI
10.1158/1535-7163.mct-15-0148

The third international meeting on genetic disorders in the RAS/MAPK pathway: Towards a therapeutic approach

Authors
Korf, B; Ahmadian, R; Allanson, J; Aoki, Y; Bakker, A; Wright, EB; Denger, B; Elgersma, Y; Gelb, BD; Gripp, KW; Kerr, B; Kontaridis, M; Lazaro, C; Linardic, C; Lozano, R; MacRae, CA; Messiaen, L; Mulero-Navarro, S; Neel, B; Plotkin, S; Rauen, KA; Roberts, A; Silva, AJ; Sittampalam, SG; Zhang, C; Schoyer, L
MLA Citation
Korf, B, Ahmadian, R, Allanson, J, Aoki, Y, Bakker, A, Wright, EB, Denger, B, Elgersma, Y, Gelb, BD, Gripp, KW, Kerr, B, Kontaridis, M, Lazaro, C, Linardic, C, Lozano, R, MacRae, CA, Messiaen, L, Mulero-Navarro, S, Neel, B, Plotkin, S, Rauen, KA, Roberts, A, Silva, AJ, Sittampalam, SG, Zhang, C, and Schoyer, L. "The third international meeting on genetic disorders in the RAS/MAPK pathway: Towards a therapeutic approach." American Journal of Medical Genetics Part A 167.8 (August 2015): 1741-1746.
Source
crossref
Published In
American Journal of Medical Genetics Part A
Volume
167
Issue
8
Publish Date
2015
Start Page
1741
End Page
1746
DOI
10.1002/ajmg.a.37089

Role of the YAP Oncoprotein in Priming Ras-Driven Rhabdomyosarcoma.

Rhabdomyosarcoma (RMS), a cancer characterized by features of skeletal muscle histogenesis, is the most common soft tissue sarcoma of childhood and adolescence. Survival for high-risk groups is less than 30% at 5 years. RMS also occurs during adulthood, with a lower incidence but higher mortality. Recently, mutational profiling has revealed a correlation between activating Ras mutations in the embryonal (eRMS) and pleomorphic (pRMS) histologic variants of RMS, and a poorer outcome for those patients. Independently, the YAP transcriptional coactivator, an oncoprotein kept in check by the Hippo tumor suppressor pathway, is upregulated in eRMS. Here we show that YAP promotes cell proliferation and antagonizes apoptosis and myogenic differentiation of human RMS cells bearing oncogenic Ras mutations in cell culture studies in vitro and in murine xenografts in vivo. Pharmacologic inhibition of YAP by the benzoporphyrin derivative verteporfin decreased cell proliferation and tumor growth in vivo. To interrogate the temporal contribution of YAP in eRMS tumorigenesis, we used a primary human cell-based genetic model of Ras-driven RMS. Constitutively active YAP functioned as an early genetic lesion, permitting bypass of senescence and priming myoblasts to tolerate subsequent expression of hTERT and oncogenic Ras, which were necessary and sufficient to generate murine xenograft tumors mimicking RMS in vivo. This work provides evidence for cooperation between YAP and oncogenic Ras in RMS tumorigenesis, laying the foundation for preclinical co-targeting of these pathways.

Authors
Slemmons, KK; Crose, LES; Rudzinski, E; Bentley, RC; Linardic, CM
MLA Citation
Slemmons, KK, Crose, LES, Rudzinski, E, Bentley, RC, and Linardic, CM. "Role of the YAP Oncoprotein in Priming Ras-Driven Rhabdomyosarcoma." PloS one 10.10 (January 2015): e0140781-.
PMID
26496700
Source
epmc
Published In
PloS one
Volume
10
Issue
10
Publish Date
2015
Start Page
e0140781
DOI
10.1371/journal.pone.0140781

A Review: Molecular Aberrations within Hippo Signaling in Bone and Soft-Tissue Sarcomas.

The Hippo signaling pathway is an evolutionarily conserved developmental network vital for the regulation of organ size, tissue homeostasis, repair and regeneration, and cell fate. The Hippo pathway has also been shown to have tumor suppressor properties. Hippo transduction involves a series of kinases and scaffolding proteins that are intricately connected to proteins in developmental cascades and in the tissue microenvironment. This network governs the downstream Hippo transcriptional co-activators, YAP and TAZ, which bind to and activate the output of TEADs, as well as other transcription factors responsible for cellular proliferation, self-renewal, differentiation, and survival. Surprisingly, there are few oncogenic mutations within the core components of the Hippo pathway. Instead, dysregulated Hippo signaling is a versatile accomplice to commonly mutated cancer pathways. For example, YAP and TAZ can be activated by oncogenic signaling from other pathways, or serve as co-activators for classical oncogenes. Emerging evidence suggests that Hippo signaling couples cell density and cytoskeletal structural changes to morphogenic signals and conveys a mesenchymal phenotype. While much of Hippo biology has been described in epithelial cell systems, it is clear that dysregulated Hippo signaling also contributes to malignancies of mesenchymal origin. This review will summarize the known molecular alterations within the Hippo pathway in sarcomas and highlight how several pharmacologic compounds have shown activity in modulating Hippo components, providing proof-of-principle that Hippo signaling may be harnessed for therapeutic application in sarcomas.

Authors
Deel, MD; Li, JJ; Crose, LES; Linardic, CM
MLA Citation
Deel, MD, Li, JJ, Crose, LES, and Linardic, CM. "A Review: Molecular Aberrations within Hippo Signaling in Bone and Soft-Tissue Sarcomas." Frontiers in oncology 5 (January 2015): 190-. (Review)
PMID
26389076
Source
epmc
Published In
Frontiers in Oncology
Volume
5
Publish Date
2015
Start Page
190
DOI
10.3389/fonc.2015.00190

Rhabdomyosarcoma: current challenges and their implications for developing therapies.

Rhabdomyosarcoma (RMS) represents a rare, heterogeneous group of mesodermal malignancies with skeletal muscle differentiation. One major subgroup of RMS tumors (so-called "fusion-positive" tumors) carries exclusive chromosomal translocations that join the DNA-binding domain of the PAX3 or PAX7 gene to the transactivation domain of the FOXO1 (previously known as FKHR) gene. Fusion-negative RMS represents a heterogeneous spectrum of tumors with frequent RAS pathway activation. Overtly metastatic disease at diagnosis is more frequently found in individuals with fusion-positive than in those with fusion-negative tumors. RMS is the most common pediatric soft-tissue sarcoma, and approximately 60% of all children and adolescents diagnosed with RMS are cured by currently available multimodal therapies. However, a curative outcome is achieved in <30% of high-risk individuals with RMS, including all those diagnosed as adults, those diagnosed with fusion-positive tumors during childhood (including metastatic and nonmetastatic tumors), and those diagnosed with metastatic disease during childhood (including fusion-positive and fusion-negative tumors). This white paper outlines current challenges in RMS research and their implications for developing more effective therapies. Urgent clinical problems include local control, systemic disease, need for improved risk stratification, and characterization of differences in disease course in children and adults. Biological challenges include definition of the cellular functions of PAX-FOXO1 fusion proteins, clarification of disease heterogeneity, elucidation of the cellular origins of RMS, delineation of the tumor microenvironment, and identification of means for rational selection and testing of new combination therapies. To streamline future therapeutic developments, it will be critical to improve access to fresh tumor tissue for research purposes, consider alternative trial designs to optimize early clinical testing of candidate drugs, coalesce advocacy efforts to garner public and industry support, and facilitate collaborative efforts between academia and industry.

Authors
Hettmer, S; Li, Z; Billin, AN; Barr, FG; Cornelison, DDW; Ehrlich, AR; Guttridge, DC; Hayes-Jordan, A; Helman, LJ; Houghton, PJ; Khan, J; Langenau, DM; Linardic, CM; Pal, R; Partridge, TA; Pavlath, GK; Rota, R; Schäfer, BW; Shipley, J; Stillman, B; Wexler, LH; Wagers, AJ; Keller, C
MLA Citation
Hettmer, S, Li, Z, Billin, AN, Barr, FG, Cornelison, DDW, Ehrlich, AR, Guttridge, DC, Hayes-Jordan, A, Helman, LJ, Houghton, PJ, Khan, J, Langenau, DM, Linardic, CM, Pal, R, Partridge, TA, Pavlath, GK, Rota, R, Schäfer, BW, Shipley, J, Stillman, B, Wexler, LH, Wagers, AJ, and Keller, C. "Rhabdomyosarcoma: current challenges and their implications for developing therapies." Cold Spring Harbor perspectives in medicine 4.11 (November 3, 2014): a025650-. (Review)
PMID
25368019
Source
epmc
Published In
Cold Spring Harbor perspectives in medicine
Volume
4
Issue
11
Publish Date
2014
Start Page
a025650
DOI
10.1101/cshperspect.a025650

Randomized phase II trial of bevacizumab and temsirolimus in combination with vinorelbine (V) and cyclophosphamide (C) for first relapse/disease progression of rhabdomyosarcoma (RMS): A report from the Children's Oncology Group (COG).

Authors
Mascarenhas, L; Meyer, WH; Lyden, E; Rodeberg, DA; Indelicato, DJ; Linardic, CM; Anderson, JR; Hawkins, DS; Comm, STS
MLA Citation
Mascarenhas, L, Meyer, WH, Lyden, E, Rodeberg, DA, Indelicato, DJ, Linardic, CM, Anderson, JR, Hawkins, DS, and Comm, STS. "Randomized phase II trial of bevacizumab and temsirolimus in combination with vinorelbine (V) and cyclophosphamide (C) for first relapse/disease progression of rhabdomyosarcoma (RMS): A report from the Children's Oncology Group (COG)." May 20, 2014.
Source
wos-lite
Published In
Journal of Clinical Oncology
Volume
32
Issue
15
Publish Date
2014

Rhabdomyosarcoma: Current challenges and their implications for developing therapies

© 2014 Cold Spring Harbor Laboratory Press; all rights reserved.Rhabdomyosarcoma (RMS) represents a rare, heterogeneous group of mesodermal malig- nancies with skeletal muscle differentiation. One major subgroup of RMS tumors (so-called “fusion-positive” tumors) carries exclusive chromosomal translocations that join the DNA- binding domain of the PAX3 or PAX7 gene to the transactivation domain of the FOXO1 (previously known as FKHR) gene. Fusion-negative RMS represents a heterogeneous spec- trum of tumors with frequent RAS pathway activation. Overtly metastatic disease at diagnosis is more frequently found in individuals with fusion-positive than in those with fusion-neg- ative tumors. RMS is the most common pediatric soft-tissue sarcoma, and approximately 60% of all children and adolescents diagnosed with RMS are cured by currently available multimodal therapies. However, a curative outcome is achieved in,30% of high-risk indi- viduals with RMS, including all those diagnosed as adults, those diagnosed with fusion- positive tumors during childhood (including metastatic and nonmetastatic tumors), and those diagnosed with metastatic disease during childhood (including fusion-positive and fusion-negative tumors). This white paper outlines current challenges in RMS research and their implications for developing more effective therapies. Urgent clinical problems include local control, systemic disease, need for improved risk stratification, and character- ization of differences in disease course in children and adults. Biological challenges include definition of the cellular functions of PAX-FOXO1 fusion proteins, clarification of disease heterogeneity, elucidation of the cellular origins of RMS, delineation of the tumor microen- vironment, and identification of means for rational selection and testing of new combination therapies. To streamline future therapeutic developments, it will be critical to improve access to fresh tumor tissue for research purposes, consider alternative trial designs to optimize early clinical testing of candidate drugs, coalesce advocacy efforts to garner public and industry support, and facilitate collaborative efforts between academia and industry.

Authors
Hettmer, S; Li, Z; Billin, AN; Barr, FG; Cornelison, D; Ehrlich, AR; Guttridge, DC; Hayes-Jordan, A; Helman, LJ; Houghton, PJ; Khan, J; Langenau, DM; Linardic, CM; Pal, R; Partridge, TA; Pavlath, GK; Rota, R; Schafer, BW; Shipley, J; Stillman, B; Wexler, LH; Wagers, AJ; Keller, C
MLA Citation
Hettmer, S, Li, Z, Billin, AN, Barr, FG, Cornelison, D, Ehrlich, AR, Guttridge, DC, Hayes-Jordan, A, Helman, LJ, Houghton, PJ, Khan, J, Langenau, DM, Linardic, CM, Pal, R, Partridge, TA, Pavlath, GK, Rota, R, Schafer, BW, Shipley, J, Stillman, B, Wexler, LH, Wagers, AJ, and Keller, C. "Rhabdomyosarcoma: Current challenges and their implications for developing therapies." Cold Spring Harbor Perspectives in Medicine 4.11 (January 1, 2014).
Source
scopus
Published In
Cold Spring Harbor perspectives in medicine
Volume
4
Issue
11
Publish Date
2014
DOI
10.1101/cshperspect.a025650

Alveolar rhabdomyosarcoma-associated PAX3-FOXO1 promotes tumorigenesis via Hippo pathway suppression.

Alveolar rhabdomyosarcoma (aRMS) is an aggressive sarcoma of skeletal muscle characterized by expression of the paired box 3-forkhead box protein O1 (PAX3-FOXO1) fusion oncogene. Despite its discovery nearly two decades ago, the mechanisms by which PAX3-FOXO1 drives tumor development are not well characterized. Previously, we reported that PAX3-FOXO1 supports aRMS initiation by enabling bypass of cellular senescence checkpoints. We have now found that this bypass occurs in part through PAX3-FOXO1-mediated upregulation of RASSF4, a Ras-association domain family (RASSF) member. RASSF4 expression was upregulated in PAX3-FOXO1-positive aRMS cell lines and tumors. Enhanced RASSF4 expression promoted cell cycle progression, senescence evasion, and tumorigenesis through inhibition of the Hippo pathway tumor suppressor MST1. We also found that the downstream Hippo pathway target Yes-associated protein 1 (YAP), which is ordinarily restrained by Hippo signaling, was upregulated in RMS tumors. These data suggest that Hippo pathway dysfunction promotes RMS. This work provides evidence for Hippo pathway suppression in aRMS and demonstrates a progrowth role for RASSF4. Additionally, we identify a mechanism used by PAX3-FOXO1 to inhibit MST1 signaling and promote tumorigenesis in aRMS.

Authors
Crose, LES; Galindo, KA; Kephart, JG; Chen, C; Fitamant, J; Bardeesy, N; Bentley, RC; Galindo, RL; Chi, J-TA; Linardic, CM
MLA Citation
Crose, LES, Galindo, KA, Kephart, JG, Chen, C, Fitamant, J, Bardeesy, N, Bentley, RC, Galindo, RL, Chi, J-TA, and Linardic, CM. "Alveolar rhabdomyosarcoma-associated PAX3-FOXO1 promotes tumorigenesis via Hippo pathway suppression." J Clin Invest 124.1 (January 2014): 285-296.
PMID
24334454
Source
pubmed
Published In
Journal of Clinical Investigation
Volume
124
Issue
1
Publish Date
2014
Start Page
285
End Page
296
DOI
10.1172/JCI67087

Asparaginase-Induced Hypertriglyceridemia Presenting as Pseudohyponatremia during Leukemia Treatment.

Asparaginase is a chemotherapeutic agent used to induce disease remission in children with acute lymphoblastic leukemia (ALL). We describe the cases of two females with ALL who developed pseudohyponatremia as a presentation of hypertriglyceridemia following asparaginase treatment. Nine similar published cases of asparaginase-induced hypertriglyceridemia and its complications are also discussed. Possible mechanisms of action include inhibition of lipoprotein lipase, decreased hepatic synthesis of lipoprotein, and increased synthesis of VLDL. Effects of asparaginase-induced hypertriglyceridemia range from asymptomatic to transaminasemia, pancreatitis, and life-threatening thrombosis or hyperviscosity syndrome. All cases of hypertriglyceridemia described resolved following cessation of asparaginase treatment ± further treatments.

Authors
Hinson, A; Newbern, D; Linardic, CM
MLA Citation
Hinson, A, Newbern, D, and Linardic, CM. "Asparaginase-Induced Hypertriglyceridemia Presenting as Pseudohyponatremia during Leukemia Treatment." Case reports in pediatrics 2014 (January 2014): 635740-.
PMID
25405049
Source
epmc
Published In
Case Reports in Pediatrics
Volume
2014
Publish Date
2014
Start Page
635740
DOI
10.1155/2014/635740

RAS and ROS in rhabdomyosarcoma.

The 5-year survival for localized rhabdomyosarcoma is over 70%, but only 30% for patients presenting with metastatic disease. In this issue of Cancer Cell, Chen and colleagues performed whole-genome and RNA sequencing on human rhabdomyosarcoma and identified RAS mutations and oxidative stress as potential therapeutic targets for high-risk embryonal rhabdomyosarcoma.

Authors
Zhang, M; Linardic, CM; Kirsch, DG
MLA Citation
Zhang, M, Linardic, CM, and Kirsch, DG. "RAS and ROS in rhabdomyosarcoma." Cancer Cell 24.6 (December 9, 2013): 689-691.
PMID
24332036
Source
pubmed
Published In
Cancer Cell
Volume
24
Issue
6
Publish Date
2013
Start Page
689
End Page
691
DOI
10.1016/j.ccr.2013.11.015

Distinct and overlapping sarcoma subtypes initiated from muscle stem and progenitor cells.

Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma in children, whereas undifferentiated pleomorphic sarcoma (UPS) is one of the most common soft tissue sarcomas diagnosed in adults. To investigate the myogenic cell(s) of origin of these sarcomas, we used Pax7-CreER and MyoD-CreER mice to transform Pax7(+) and MyoD(+) myogenic progenitors by expressing oncogenic Kras(G12D) and deleting Trp53 in vivo. Pax7-CreER mice developed RMS and UPS, whereas MyoD-CreER mice developed UPS. Using gene set enrichment analysis, RMS and UPS each clustered specifically within their human counterparts. These results suggest that RMS and UPS have distinct and overlapping cells of origin within the muscle lineage. Taking them together, we have established mouse models of soft tissue sarcoma from muscle stem and progenitor cells.

Authors
Blum, JM; Añó, L; Li, Z; Van Mater, D; Bennett, BD; Sachdeva, M; Lagutina, I; Zhang, M; Mito, JK; Dodd, LG; Cardona, DM; Dodd, RD; Williams, N; Ma, Y; Lepper, C; Linardic, CM; Mukherjee, S; Grosveld, GC; Fan, C-M; Kirsch, DG
MLA Citation
Blum, JM, Añó, L, Li, Z, Van Mater, D, Bennett, BD, Sachdeva, M, Lagutina, I, Zhang, M, Mito, JK, Dodd, LG, Cardona, DM, Dodd, RD, Williams, N, Ma, Y, Lepper, C, Linardic, CM, Mukherjee, S, Grosveld, GC, Fan, C-M, and Kirsch, DG. "Distinct and overlapping sarcoma subtypes initiated from muscle stem and progenitor cells." Cell Rep 5.4 (November 27, 2013): 933-940.
PMID
24239359
Source
pubmed
Published In
Cell Reports
Volume
5
Issue
4
Publish Date
2013
Start Page
933
End Page
940
DOI
10.1016/j.celrep.2013.10.020

Human rhabdomyosarcoma cell lines for rhabdomyosarcoma research: utility and pitfalls.

Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma of childhood and adolescence. Despite intergroup clinical trials conducted in Europe and North America, outcomes for high risk patients with this disease have not significantly improved in the last several decades, and survival of metastatic or relapsed disease remains extremely poor. Accrual into new clinical trials is slow and difficult, so in vitro cell-line research and in vivo xenograft models present an attractive alternative for preclinical research for this cancer type. Currently, 30 commonly used human RMS cell lines exist, with differing origins, karyotypes, histologies, and methods of validation. Selecting an appropriate cell line for RMS research has important implications for outcomes. There are also potential pitfalls in using certain cell lines including contamination with murine stromal cells, cross-contamination between cell lines, discordance between the cell line and its associated original tumor, imposter cell lines, and nomenclature errors that result in the circulation of two or more presumed unique cell lines that are actually from the same origin. These pitfalls can be avoided by testing for species-specific isoenzymes, microarray analysis, assays for subtype-specific fusion products, and short tandem repeat analysis.

Authors
Hinson, ARP; Jones, R; Crose, LES; Belyea, BC; Barr, FG; Linardic, CM
MLA Citation
Hinson, ARP, Jones, R, Crose, LES, Belyea, BC, Barr, FG, and Linardic, CM. "Human rhabdomyosarcoma cell lines for rhabdomyosarcoma research: utility and pitfalls. (Published online)" Front Oncol 3 (2013): 183-.
PMID
23882450
Source
pubmed
Published In
Front Oncol
Volume
3
Publish Date
2013
Start Page
183
DOI
10.3389/fonc.2013.00183

FGFR4 blockade exerts distinct antitumorigenic effects in human embryonal versus alveolar rhabdomyosarcoma.

PURPOSE: Rhabdomyosarcoma (RMS) is a malignancy with features of skeletal muscle, and the most common soft tissue sarcoma of childhood. Survival for high-risk groups is approximately 30% at 5 years and there are no durable therapies tailored to its genetic aberrations. During genetic modeling of the common RMS variants, embryonal RMS (eRMS) and alveolar RMS (aRMS), we noted that the receptor tyrosine kinase (RTK) fibroblast growth factor receptor 4 (FGFR4) was upregulated as an early event in aRMS. Herein, we evaluated the expression of FGFR4 in eRMS compared with aRMS, and whether FGFR4 had similar or distinct roles in their tumorigenesis. EXPERIMENTAL DESIGN: Human RMS cell lines and tumor tissue were analyzed for FGFR4 expression by immunoblot and immunohistochemistry. Genetic and pharmacologic loss-of-function of FGFR4 using virally transduced short hairpin RNA (shRNA) and the FGFR small-molecule inhibitor PD173074, respectively, were used to study the role of FGFR4 in RMS cell lines in vitro and xenografts in vivo. Expression of the antiapoptotic protein BCL2L1 was also examined. RESULTS: FGFR4 is expressed in both RMS subtypes, but protein expression is higher in aRMS. The signature aRMS gene fusion product, PAX3-FOXO1, induced FGFR4 expression in primary human myoblasts. In eRMS, FGFR4 loss-of-function reduced cell proliferation in vitro and xenograft formation in vivo. In aRMS, it diminished cell survival in vitro. In myoblasts and aRMS, FGFR4 was necessary and sufficient for expression of BCL2L1 whereas in eRMS, this induction was not observed, suggesting differential FGFR4 signaling. CONCLUSION: These studies define dichotomous roles for FGFR4 in RMS subtypes, and support further study of FGFR4 as a therapeutic target.

Authors
Crose, LES; Etheridge, KT; Chen, C; Belyea, B; Talbot, LJ; Bentley, RC; Linardic, CM
MLA Citation
Crose, LES, Etheridge, KT, Chen, C, Belyea, B, Talbot, LJ, Bentley, RC, and Linardic, CM. "FGFR4 blockade exerts distinct antitumorigenic effects in human embryonal versus alveolar rhabdomyosarcoma." Clin Cancer Res 18.14 (July 15, 2012): 3780-3790.
PMID
22648271
Source
pubmed
Published In
Clinical cancer research : an official journal of the American Association for Cancer Research
Volume
18
Issue
14
Publish Date
2012
Start Page
3780
End Page
3790
DOI
10.1158/1078-0432.CCR-10-3063

In vivo imaging of tumor-propagating cells, regional tumor heterogeneity, and dynamic cell movements in embryonal rhabdomyosarcoma.

Embryonal rhabdomyosarcoma (ERMS) is an aggressive pediatric sarcoma of muscle. Here, we show that ERMS-propagating potential is confined to myf5+ cells and can be visualized in live, fluorescent transgenic zebrafish. During early tumor growth, myf5+ ERMS cells reside adjacent normal muscle fibers. By late-stage ERMS, myf5+ cells are reorganized into distinct regions separated from differentiated tumor cells. Time-lapse imaging of late-stage ERMS revealed that myf5+ cells populate newly formed tumor only after seeding by highly migratory myogenin+ ERMS cells. Moreover, myogenin+ ERMS cells can enter the vasculature, whereas myf5+ ERMS-propagating cells do not. Our data suggest that non-tumor-propagating cells likely have important supportive roles in cancer progression and facilitate metastasis.

Authors
Ignatius, MS; Chen, E; Elpek, NM; Fuller, AZ; Tenente, IM; Clagg, R; Liu, S; Blackburn, JS; Linardic, CM; Rosenberg, AE; Nielsen, PG; Mempel, TR; Langenau, DM
MLA Citation
Ignatius, MS, Chen, E, Elpek, NM, Fuller, AZ, Tenente, IM, Clagg, R, Liu, S, Blackburn, JS, Linardic, CM, Rosenberg, AE, Nielsen, PG, Mempel, TR, and Langenau, DM. "In vivo imaging of tumor-propagating cells, regional tumor heterogeneity, and dynamic cell movements in embryonal rhabdomyosarcoma." Cancer Cell 21.5 (May 15, 2012): 680-693.
PMID
22624717
Source
pubmed
Published In
Cancer Cell
Volume
21
Issue
5
Publish Date
2012
Start Page
680
End Page
693
DOI
10.1016/j.ccr.2012.03.043

Recurrent inflammatory myofibroblastic tumor of the heart.

Authors
Andersen, ND; DiBernardo, LR; Linardic, CM; Camitta, MGW; Lodge, AJ
MLA Citation
Andersen, ND, DiBernardo, LR, Linardic, CM, Camitta, MGW, and Lodge, AJ. "Recurrent inflammatory myofibroblastic tumor of the heart." Circulation 125.19 (May 15, 2012): 2379-2381.
PMID
22586293
Source
pubmed
Published In
Circulation
Volume
125
Issue
19
Publish Date
2012
Start Page
2379
End Page
2381
DOI
10.1161/CIRCULATIONAHA.111.066191

Embryonic signaling pathways and rhabdomyosarcoma: contributions to cancer development and opportunities for therapeutic targeting.

Rhabdomyosarcoma is the most common soft tissue sarcoma of childhood and adolescence, accounting for approximately 7% of childhood cancers. Current therapies include nonspecific cytotoxic chemotherapy regimens, radiation therapy, and surgery; however, these multimodality strategies are unsuccessful in the majority of patients with high-risk disease. It is generally believed that these tumors represent arrested or aberrant skeletal muscle development, and, accordingly, developmental signaling pathways critical to myogenesis such as Notch, WNT, and Hedgehog may represent new therapeutic targets. In this paper, we summarize the current preclinical studies linking these embryonic pathways to rhabdomyosarcoma tumorigenesis and provide support for the investigation of targeted therapies in this embryonic cancer.

Authors
Belyea, B; Kephart, JG; Blum, J; Kirsch, DG; Linardic, CM
MLA Citation
Belyea, B, Kephart, JG, Blum, J, Kirsch, DG, and Linardic, CM. "Embryonic signaling pathways and rhabdomyosarcoma: contributions to cancer development and opportunities for therapeutic targeting." Sarcoma 2012 (2012): 406239-.
PMID
22619564
Source
pubmed
Published In
Sarcoma
Volume
2012
Publish Date
2012
Start Page
406239
DOI
10.1155/2012/406239

Inhibition of rhabdomyosarcoma cell and tumor growth by targeting specificity protein (Sp) transcription factors

Specificity protein (Sp) transcription factors Sp1, Sp3 and Sp4 are highly expressed in rhabdomyosarcoma (RMS) cells. In tissue arrays of RMS tumor cores from 71 patients, 80% of RMS patients expressed high levels of Sp1 protein, whereas low expression of Sp1 was detected in normal muscle tissue. The non-steroidal anti-inflammatory drug (NSAID) tolfenamic acid (TA) inhibited growth and migration of RD and RH30 RMS cell lines and also inhibited tumor growth in vivo using a mouse xenograft (RH30 cells) model. The effects of TA were accompanied by downregulation of Sp1, Sp3, Sp4 and Sp-regulated genes in RMS cells and tumors, and the role of Sp protein downregulation in mediating inhibition of RD and RH30 cell growth and migration was confirmed by individual and combined knockdown of Sp1, Sp3 and Sp4 proteins by RNA interference. TA treatment and Sp knockdown in RD and RH30 cells also showed that four genes that are emerging as individual drug targets for treating RMS, namely c-MET, insulin-like growth factor receptor (IGFR), PDGFRα and CXCR4, are also Sp-regulated genes. These results suggest that NSAIDs such as TA may have potential clinical efficacy in drug combinations for treating RMS patients. Copyright © 2012 UICC.

Authors
Chadalapaka, G; Jutooru, I; Sreevalsan, S; Pathi, S; Kim, K; Chen, C; Crose, L; Linardic, C; Safe, S
MLA Citation
Chadalapaka, G, Jutooru, I, Sreevalsan, S, Pathi, S, Kim, K, Chen, C, Crose, L, Linardic, C, and Safe, S. "Inhibition of rhabdomyosarcoma cell and tumor growth by targeting specificity protein (Sp) transcription factors." International Journal of Cancer 132.4 (2012): 795-806.
PMID
22815231
Source
scival
Published In
International Journal of Cancer
Volume
132
Issue
4
Publish Date
2012
Start Page
795
End Page
806
DOI
10.1002/ijc.27730

Inhibition of the Notch-Hey1 axis blocks embryonal rhabdomyosarcoma tumorigenesis.

PURPOSE: Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma of childhood and remains refractory to combined-modality therapy in patients with high risk disease. In skeletal myogenesis, Notch signaling prevents muscle differentiation and promotes proliferation of satellite cell progeny. Given its physiologic role in myogenesis and oncogenic role in other human cancers, we hypothesized that aberrant Notch signaling may contribute to RMS tumorigenesis and present novel therapeutic opportunities. EXPERIMENTAL DESIGN: Human RMS cell lines and tumors were evaluated by immunoblot, IHC, and RT-PCR to measure Notch ligand, receptor, and target gene expression. Manipulation of Notch signaling was accomplished using genetic and pharmacologic approaches. In vitro cell growth, proliferation, and differentiation were assessed using colorimetric MTT and BrdU assays, and biochemical/morphologic changes after incubation in differentiation-promoting media, respectively. In vivo tumorigenesis was assessed using xenograft formation in SCID/beige mice. RESULTS: Notch signaling is upregulated in human RMS cell lines and tumors compared with primary skeletal muscle, especially in the embryonal (eRMS) subtype. Inhibition of Notch signaling using Notch1 RNAi or γ-secretase inhibitors reduced eRMS cell proliferation in vitro. Hey1 RNAi phenocopied Notch1 loss and permitted modest myogenic differentiation, while overexpression of an activated Notch moiety, ICN1, promoted eRMS cell proliferation and rescued pharmacologic inhibition. Finally, Notch inhibition using RNAi or γ-secretase inhibitors blocked tumorigenesis in vivo. CONCLUSIONS: Aberrant Notch-Hey1 signaling contributes to eRMS by impeding differentiation and promoting proliferation. The efficacy of Notch pathway inhibition in vivo supports the development of Notch-Hey1 axis inhibitors in the treatment of eRMS.

Authors
Belyea, BC; Naini, S; Bentley, RC; Linardic, CM
MLA Citation
Belyea, BC, Naini, S, Bentley, RC, and Linardic, CM. "Inhibition of the Notch-Hey1 axis blocks embryonal rhabdomyosarcoma tumorigenesis." Clin Cancer Res 17.23 (December 1, 2011): 7324-7336.
PMID
21948088
Source
pubmed
Published In
Clinical cancer research : an official journal of the American Association for Cancer Research
Volume
17
Issue
23
Publish Date
2011
Start Page
7324
End Page
7336
DOI
10.1158/1078-0432.CCR-11-1004

Receptor tyrosine kinases as therapeutic targets in rhabdomyosarcoma.

Rhabdomyosarcomas (RMSs) are the most common soft tissue sarcomas of childhood and adolescence. To date, there are no effective treatments that target the genetic abnormalities in RMS, and current treatment options for high-risk groups are not adequate. Over the past two decades, research into the molecular mechanisms of RMS has identified key genes and signaling pathways involved in disease pathogenesis. In these studies, members of the receptor tyrosine kinase (RTK) family of cell surface receptors have been characterized as druggable targets for RMS. Through small molecule inhibitors, ligand-neutralizing agents, and monoclonal receptor-blocking antibodies, RTK activity can be manipulated to block oncogenic properties associated with RMS. Herein, we review the members of the RTK family that are implicated in RMS tumorigenesis and discuss both the problems and promise of targeting RTKs in RMS.

Authors
Crose, LES; Linardic, CM
MLA Citation
Crose, LES, and Linardic, CM. "Receptor tyrosine kinases as therapeutic targets in rhabdomyosarcoma." Sarcoma 2011 (2011): 756982-.
PMID
21253475
Source
pubmed
Published In
Sarcoma
Volume
2011
Publish Date
2011
Start Page
756982
DOI
10.1155/2011/756982

Local therapy for rhabdomyosarcoma of the hands and feet: Is amputation necessary? A report from the children's oncology group

Purpose: To evaluate the outcome of children with rhabdomyosarcoma (RMS) of the hand or foot treated with surgery and/or local radiotherapy (RT). Methods and Materials: Forty-eight patients with nonmetastatic RMS of the hand or foot were enrolled on Intergroup Rhabdomyosarcoma Study III, IV-Pilot, and IV. Patients received multiagent chemotherapy with surgery and/or RT. Twenty-four patients (50%) underwent surgery without local RT, of whom 4 had complete resection and 20 had an amputation. The remaining 24 patients (50%) underwent local RT, of whom 2 required RT for microscopic residual disease after prior amputation. Median follow-up for surviving patients was 9.7 years. Results: Actuarial 10-year local control was 100%; 10-year event-free survival and overall survival rates were 62% and 63%, respectively. Poor prognostic factors for recurrence included gross residual (Group III) disease and nodal involvement (p = 0.01 and 0.05, respectively). More patients in the RT group had alveolar histology, Group III disease, and nodal involvement, as compared with the surgery group. There was no difference in 10-year event-free survival (57% vs. 66%) or overall survival (63% vs. 63%) between patients who underwent surgery or local RT. Among relapsing patients, there were no long-term survivors. No secondary malignancies have been observed. Conclusions: Despite having high-risk features, patients treated with local RT achieved excellent local control. Complete surgical resection without amputation is difficult to achieve in the hand or foot. Therefore, we recommend either definitive RT or surgical resection that maintains form and function as primary local therapy rather than amputation in patients with hand or foot RMS. © 2011 Elsevier Inc.

Authors
La, TH; Wolden, SL; Su, Z; Linardic, C; Randall, RL; Hawkins, DS; Donaldson, SS
MLA Citation
La, TH, Wolden, SL, Su, Z, Linardic, C, Randall, RL, Hawkins, DS, and Donaldson, SS. "Local therapy for rhabdomyosarcoma of the hands and feet: Is amputation necessary? A report from the children's oncology group." International Journal of Radiation Oncology Biology Physics 80.1 (2011): 206-212.
PMID
20646853
Source
scival
Published In
International Journal of Radiation Oncology, Biology, Physics
Volume
80
Issue
1
Publish Date
2011
Start Page
206
End Page
212
DOI
10.1016/j.ijrobp.2010.01.053

Defining the cooperative genetic changes that temporally drive alveolar rhabdomyosarcoma.

Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma of childhood and adolescence. Despite advances in therapy, patients with a histologic variant of RMS known as alveolar (aRMS) have a 5-year survival rate of <30%. aRMS tissues exhibit a number of genetic changes, including loss-of-function of the p53 and Rb tumor suppressor pathways, amplification of MYCN, stabilization of telomeres, and most characteristically, reciprocal translocation of loci involving the PAX and FKHR genes, generating the PAX7-FKHR or PAX3-FKHR fusion proteins. We previously showed that PAX3-FKHR expression in primary human myoblasts, cells that can give rise to RMS, cooperated with loss of p16INK4A to promote extended proliferation. To better understand the genetic events required for aRMS formation, we then stepwise converted these cells to their transformed counterpart. PAX3-FKHR, the catalytic unit of telomerase hTERT, and MycN, in cooperation with down-regulation of p16INK4A/p14ARF expression, were necessary and sufficient to convert normal human myoblasts into tumorigenic cells that gave rise to aRMS tumors. However, the order of expression of these transgenes was critical, as only those cells expressing PAX3-FKHR early could form tumors. We therefore suggest that the translocation of PAX3 to FKHR drives proliferation of myoblasts, and a selection for loss of p16INK4A/p14ARF. These early steps, coupled with MycN amplification and telomere stabilization, then drive the cells to a fully tumorigenic state.

Authors
Naini, S; Etheridge, KT; Adam, SJ; Qualman, SJ; Bentley, RC; Counter, CM; Linardic, CM
MLA Citation
Naini, S, Etheridge, KT, Adam, SJ, Qualman, SJ, Bentley, RC, Counter, CM, and Linardic, CM. "Defining the cooperative genetic changes that temporally drive alveolar rhabdomyosarcoma." Cancer Res 68.23 (December 1, 2008): 9583-9588.
PMID
19047133
Source
pubmed
Published In
Cancer Research
Volume
68
Issue
23
Publish Date
2008
Start Page
9583
End Page
9588
DOI
10.1158/0008-5472.CAN-07-6178

PAX3-FOXO1 fusion gene in rhabdomyosarcoma.

Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma of childhood and adolescence. The predominant histologic variants of this disease are termed embryonal (eRMS) and alveolar (aRMS), based on their appearance under light microscopy. Of the two, aRMS is associated with an more aggressive disease pattern and a higher mortality, mandating a better understanding of this cancer at the molecular level. The PAX3-FOXO1 fusion gene, resulting from the stable reciprocal translocation of chromosomes 2 and 13, is a signature genetic change found only in aRMS, and thought to be responsible at least in part for its malignant phenotype. This review will discuss the clinical significance of the PAX3-FOXO1 fusion gene, the pertinent historical and current models used to study its oncogenic contributions, the transcriptional targets that are thought to mediate these contributions, and the cellular mechanisms impacted by PAX3-FOXO1 that ultimately lead to aRMS.

Authors
Linardic, CM
MLA Citation
Linardic, CM. "PAX3-FOXO1 fusion gene in rhabdomyosarcoma." Cancer Lett 270.1 (October 18, 2008): 10-18. (Review)
PMID
18457914
Source
pubmed
Published In
Cancer Letters
Volume
270
Issue
1
Publish Date
2008
Start Page
10
End Page
18
DOI
10.1016/j.canlet.2008.03.035

Genetic modeling of Ras-induced human rhabdomyosarcoma.

Rhabdomyosarcoma is the most common soft tissue sarcoma of childhood and adolescence. Historically, rhabdomyosarcoma has been studied by the manipulation of human cell lines derived from primary rhabdomyosarcoma tumor tissue adapted to grow in culture. Recently, mouse models have been added to the arsenal of tools to study this disease in vivo. However, given the emerging understanding of the genetic variability and mutability of human tumor-derived cell lines, and the existing differences between human and murine tumorigenesis, we sought to uniformly dissect the genetic events required to generate rhabdomyosarcoma from primary human skeletal muscle precursors. To this end, primary human skeletal muscle cells were transformed with defined genetic elements to corrupt the p53, Rb, Myc, telomerase, and Ras pathways, resulting in cells that, when assayed as subcutaneous xenografts in immunocompromised mice, formed tumors indistinguishable at the immunohistochemical level from the embryonal histologic variant of rhabdomyosarcoma. This chapter will discuss the techniques used to transform primary human skeletal muscle cells, the assays used to verify expression of the ectopically expressed genetic elements, and the methods used to evaluate the tumorigenic capacity of the resulting cell lines.

Authors
Linardic, CM; Counter, CM
MLA Citation
Linardic, CM, and Counter, CM. "Genetic modeling of Ras-induced human rhabdomyosarcoma." Methods Enzymol 438 (2008): 419-427.
PMID
18413264
Source
pubmed
Published In
Methods in Enzymology
Volume
438
Publish Date
2008
Start Page
419
End Page
427
DOI
10.1016/S0076-6879(07)38028-2

The PAX3-FKHR fusion gene of rhabdomyosarcoma cooperates with loss of p16INK4A to promote bypass of cellular senescence.

Rhabdomyosarcoma is the most common soft tissue sarcoma of childhood and adolescence. Despite advances in therapy, patients with a histologic variant of rhabdomyosarcoma known as alveolar rhabdomyosarcoma (ARMS) have a 5-year survival of <30%. ARMS is characterized by a chromosomal translocation generating the PAX3-FKHR fusion gene. However, ectopic expression of PAX3-FKHR often induces inhibition of cell proliferation, or cell death, when expressed in nonmuscle cells. This prompted us to explore the effect of expressing PAX3-FKHR in more relevant cells, specifically primary human skeletal muscle cells because these cells can be converted to a tumorigenic state that mimics rhabdomyosarcoma. PAX3-FKHR expression promoted both fetal and postnatal primary human skeletal muscle cell precursors to bypass the senescence growth arrest checkpoint. This bypass was accompanied by epigenetic DNA methylation of the p16(INK4A) promoter and correspondingly a loss of expression of this tumor suppressor. Knockdown of p16(INK4A) cooperated with PAX3-FKHR to drive proliferation past senescence, whereas reintroduction of wild-type p16(INK4A) in post-senescent cells caused growth arrest. Thus, PAX3-FKHR acts in concert with loss of p16(INK4A) to promote inappropriate proliferation of skeletal muscle cells. This association between PAX3-FKHR expression and p16(INK4A) loss was seen in human ARMS tumor tissue, as both human rhabdomyosarcoma cell lines and tissue microarrays showed a trend toward down-regulation of p16(INK4A) protein in alveolar subsets. We surmise that the generation of the PAX3-FKHR fusion protein may require loss of p16(INK4A) to promote malignant proliferation of skeletal muscle cells as an early step in ARMS tumorigenesis.

Authors
Linardic, CM; Naini, S; Herndon, JE; Kesserwan, C; Qualman, SJ; Counter, CM
MLA Citation
Linardic, CM, Naini, S, Herndon, JE, Kesserwan, C, Qualman, SJ, and Counter, CM. "The PAX3-FKHR fusion gene of rhabdomyosarcoma cooperates with loss of p16INK4A to promote bypass of cellular senescence." Cancer Res 67.14 (July 15, 2007): 6691-6699.
PMID
17638879
Source
pubmed
Published In
Cancer Research
Volume
67
Issue
14
Publish Date
2007
Start Page
6691
End Page
6699
DOI
10.1158/0008-5472.CAN-06-3210

Genetic modeling of alveolar rhabdomyosarcoma

Authors
Linardic, CM; Naini, S; Adam, SJ; Bentley, R; Counter, CM
MLA Citation
Linardic, CM, Naini, S, Adam, SJ, Bentley, R, and Counter, CM. "Genetic modeling of alveolar rhabdomyosarcoma." PEDIATRIC BLOOD & CANCER 48.6 (June 1, 2007): 624-624.
Source
wos-lite
Published In
Pediatric Blood & Cancer
Volume
48
Issue
6
Publish Date
2007
Start Page
624
End Page
624

A network of genetic events sufficient to convert normal human cells to a tumorigenic state.

Although great progress has been made at identifying and characterizing individual genes involved in cancer, less is known about how the combination of such genes collaborate to form tumors in humans. To this end, we sought to genetically recreate tumorigenesis in normal human cells using genes altered in human cancer. We now show that expression of mammalian proteins that inactivate the tumor suppressors Rb and p53 in conjunction with the oncoproteins Ras and Myc and the telomerase subunit hTERT is sufficient to drive a number of normal human somatic cells to a tumorigenic fate. This provides a blueprint of the events that lead to human cancer, allowing different cancers to be genetically modeled from normal human cells.

Authors
Kendall, SD; Linardic, CM; Adam, SJ; Counter, CM
MLA Citation
Kendall, SD, Linardic, CM, Adam, SJ, and Counter, CM. "A network of genetic events sufficient to convert normal human cells to a tumorigenic state." Cancer Res 65.21 (November 1, 2005): 9824-9828.
PMID
16267004
Source
pubmed
Published In
Cancer Research
Volume
65
Issue
21
Publish Date
2005
Start Page
9824
End Page
9828
DOI
10.1158/0008-5472.CAN-05-1543

Genetic modeling of human rhabdomyosarcoma.

Rhabdomyosarcoma, a malignancy showing features of skeletal muscle differentiation, is the most common soft tissue sarcoma of childhood. The identification of distinct clinical presentation patterns, histologic tumor types, and risk groups suggests that rhabdomyosarcoma is a collection of highly related sarcomas rather than a single entity. In an effort to understand this seemingly heterogeneous malignancy, we constructed a genetically defined but malleable model of rhabdomyosarcoma by converting less differentiated human skeletal muscle cell precursors (SkMC) and committed human skeletal muscle myoblasts (HSMM) into their malignant counterparts by targeting pathways altered in rhabdomyosarcoma. Whereas the two cell types were both tumorigenic, SkMCs gave rise to highly heterogeneous tumors occasionally displaying features of rhabdomyosarcoma, whereas HSMMs formed rhabdomyosarcoma-like tumors with an embryonal morphology, capable of invasion and metastasis. Thus, despite introducing the same panel of genetic changes, altering the skeletal muscle cell of origin led to different tumor morphologies, suggesting that cell of origin may dictate rhabdomyosarcoma tumor histology. The ability to now genetically induce human rhabdomyosarcoma-like tumors provides a representative model to dissect the molecular mechanisms underlying this cancer.

Authors
Linardic, CM; Downie, DL; Qualman, S; Bentley, RC; Counter, CM
MLA Citation
Linardic, CM, Downie, DL, Qualman, S, Bentley, RC, and Counter, CM. "Genetic modeling of human rhabdomyosarcoma." Cancer Res 65.11 (June 1, 2005): 4490-4495.
PMID
15930263
Source
pubmed
Published In
Cancer Research
Volume
65
Issue
11
Publish Date
2005
Start Page
4490
End Page
4495
DOI
10.1158/0008-5472.CAN-04-3194

Rescue of an hTERT mutant defective in telomere elongation by fusion with hPot1.

The protein hPot1 shares homology with telomere-binding proteins in lower eukaryotes and associates with single-stranded telomeric DNA in vitro as well as colocalizing with telomere-binding proteins in vivo. We now show that hPot1 is coimmunoprecipitated with telomeric DNA and that stable expression of this protein in telomerase-positive cells results in telomere elongation, supporting the idea that hPot1 is a bona fide mammalian telomere-binding protein. We previously found that mutations in the N-terminal DAT domain of the hTERT catalytic subunit of telomerase rendered the enzyme catalytically active but unable to elongate telomeres in vivo. This phenotype could be partially rescued by fusion with the double-stranded telomeric protein hTRF2. Given that hPot1 binds to single-stranded DNA in vitro (at the same site that hTERT binds to in vivo), we addressed whether fusion of hPot1 can rescue the DAT mutations more efficiently than that of hTRF2. We now report that a DAT mutant of hTERT is indeed efficiently rescued upon fusion to hPot1. However, this rescue depended on the ability of hPot1 to localize to telomeres rather than binding to DNA per se. These data support a model whereby the DAT domain of hTERT is implicated in telomere-telomerase associations.

Authors
Armbruster, BN; Linardic, CM; Veldman, T; Bansal, NP; Downie, DL; Counter, CM
MLA Citation
Armbruster, BN, Linardic, CM, Veldman, T, Bansal, NP, Downie, DL, and Counter, CM. "Rescue of an hTERT mutant defective in telomere elongation by fusion with hPot1." Mol Cell Biol 24.8 (April 2004): 3552-3561.
PMID
15060173
Source
pubmed
Published In
Molecular and Cellular Biology
Volume
24
Issue
8
Publish Date
2004
Start Page
3552
End Page
3561

Differential effects of rapamycin on mammalian target of rapamycin signaling functions in mammalian cells.

Rapamycin and its analogues have shown promising anticancer activities in preclinical and clinical studies. However, the mechanism whereby rapamycin inhibits signaling through the mammalian target of rapamycin (mTOR) remains poorly understood. Here, we show that the FKBP12/rapamycin complex is an essentially irreversible inhibitor of mTOR kinase activity in vitro. However, we observe no suppression of mTOR catalytic activity after immunoprecipitation from rapamycin-treated cells. These results suggest either that rapamycin acts as a reversible kinase inhibitor in intact cells or that the cellular effects of rapamycin are not mediated through global suppression in mTOR kinase activity. To better understand the cellular pharmacology of rapamycin, we compared the individual and combined effects of rapamycin and kinase-inactive mTOR expression on a panel of mTOR-dependent cellular responses. These studies identified glycolytic activity, amino acid transporter trafficking, and Akt kinase activity as novel, mTOR-modulated functions in mammalian cells. Whereas kinase-inactive mTOR did not enhance the decreases in cell size and glycolysis induced by rapamycin, expression of this mTOR mutant significantly enhanced the inhibitory effects of rapamycin on cell proliferation, 4EBP1 phosphorylation, and Akt activity. Unexpectedly, amino acid transporter trafficking was perturbed by kinase-inactive mTOR but not by rapamycin, indicating that this process is rapamycin insensitive. These results indicate that rapamycin exerts variable inhibitory actions on mTOR signaling functions and suggest that direct inhibitors of the mTOR kinase domain will display substantially broader anticancer activities than rapamycin.

Authors
Edinger, AL; Linardic, CM; Chiang, GG; Thompson, CB; Abraham, RT
MLA Citation
Edinger, AL, Linardic, CM, Chiang, GG, Thompson, CB, and Abraham, RT. "Differential effects of rapamycin on mammalian target of rapamycin signaling functions in mammalian cells." Cancer Res 63.23 (December 1, 2003): 8451-8460.
PMID
14679009
Source
pubmed
Published In
Cancer Research
Volume
63
Issue
23
Publish Date
2003
Start Page
8451
End Page
8460

Characterization of the cytotoxic activities of novel analogues of the antitumor agent, lavendamycin.

Lavendamycin is a bacterially derived quinolinedione that displays significant antimicrobial and antitumor activities. However, preclinical development of lavendamycin as an anticancer agent was halted due to the poor aqueous solubility and relatively nonspecific cytotoxic activity of this compound. In this report, we have examined the cytotoxic activities of a series of novel lavendamycin analogues. The cytotoxic activities of these compounds were evaluated in clonogenic survival assays with A549 lung carcinoma cells. Compounds bearing an amide or amine substituent at the R(3) position were the most potent inhibitors of colony formation. MB-97, the most active member of this subgroup, decreased clonogenic outgrowth by 70% at a concentration of 10 n. Treatment of A549 cells with MB-97 led to an increase in p53 protein expression and phosphorylation and a concomitant increase in the expression of the p53 target gene, p21. Exposure of p53-positive cells to MB-97 triggered cell cycle arrest in G(1) and G(2) phases but induced a selective G(2)-phase arrest in p53-negative cells. MB-97 treatment also induced a higher level of apoptosis in p53-null cells relative to their p53-positive counterparts. Finally, MB-97 showed significant cytotoxic activity in the National Cancer Institute's panel of 60 cancer cell lines and antitumor activity in vivo in hollow fiber tumorigenesis assays.

Authors
Fang, Y; Linardic, CM; Richardson, DA; Cai, W; Behforouz, M; Abraham, RT
MLA Citation
Fang, Y, Linardic, CM, Richardson, DA, Cai, W, Behforouz, M, and Abraham, RT. "Characterization of the cytotoxic activities of novel analogues of the antitumor agent, lavendamycin." Mol Cancer Ther 2.6 (June 2003): 517-526.
PMID
12813130
Source
pubmed
Published In
Molecular cancer therapeutics
Volume
2
Issue
6
Publish Date
2003
Start Page
517
End Page
526

Myelodysplasia as masquerader: A woman with hypereosinophilic syndrome and twelve years of "chronic ITP".

Authors
Linardic, CM; Gong, JZ; Rosoff, PM
MLA Citation
Linardic, CM, Gong, JZ, and Rosoff, PM. "Myelodysplasia as masquerader: A woman with hypereosinophilic syndrome and twelve years of "chronic ITP"." Med Pediatr Oncol 39.2 (August 2002): 137-138.
PMID
12116065
Source
pubmed
Published In
Pediatric Blood and Cancer
Volume
39
Issue
2
Publish Date
2002
Start Page
137
End Page
138
DOI
10.1002/mpo.10085

A pharmacologic and genetic model for investigating the role of the mammalian target of rapamycin in the control of cell growth and proliferation

Authors
Linardic, CM; Hudson, CC; Abraham, RT
MLA Citation
Linardic, CM, Hudson, CC, and Abraham, RT. "A pharmacologic and genetic model for investigating the role of the mammalian target of rapamycin in the control of cell growth and proliferation." PEDIATRIC RESEARCH 51.4 (April 2002): 254A-254A.
Source
wos-lite
Published In
Pediatric Research
Volume
51
Issue
4
Publish Date
2002
Start Page
254A
End Page
254A

Acquired hypoprothrombinemia: effects of danazol treatment.

The lupus anticoagulant may be accompanied by an acquired factor II deficiency and bleeding. We report on a patient with a lupus anticoagulant and factor II (Fll) deficiency responsive to Danazol. Acquired hypoprothrombinemia (FII) with the lupus anticoagulant (LA) may be accompanied by a hemorrhagic diathesis. A 64-year-old male with discoid lupus erythematosis bled after an intestinal polypectomy. His FII level was 18%, and his FII antigen level was 20%. Danazol (D) (600 mg per day) administration was associated with a rise in FII activity and antigen to 50% within 10 days. The patient underwent abdominal surgery. We studied the effect(s) of D on the FII level and on other coagulation factors in this patient. The patient's plasma FII antigen had a single precipitin arc compared to the two peaks of normal plasma on counterimmunoelectrophoresis with Ca++. The samples pre- and during D therapy had the same positively charged arc as normal samples, although they were quantitatively different. Neuraminidase treatment demonstrated a decrease in the positively charged migration of normal and the patient's FII antigen. Affinity chromatography of normal and patient plasma on a Sepharose protein A column revealed FII antigen present in the patient's bound fraction. The relative percentages of bound FII before and during D treatment were similar. During D therapy, levels of FIX and X rose 50-100%, and protein C rose 20-25%, while free protein S did not change. D is an effective therapy for acquired FII deficiency associated with LA. D does not affect the binding of Ig to FII, but D raises FII levels by increasing synthesis of the FII protein.

Authors
Williams, S; Linardic, C; Wilson, O; Comp, P; Gralnick, HR
MLA Citation
Williams, S, Linardic, C, Wilson, O, Comp, P, and Gralnick, HR. "Acquired hypoprothrombinemia: effects of danazol treatment." American journal of hematology 53.4 (December 1996): 272-276.
PMID
8948670
Source
epmc
Published In
American Journal of Hematology
Volume
53
Issue
4
Publish Date
1996
Start Page
272
End Page
276
DOI
10.1002/(sici)1096-8652(199612)53:4<272::aid-ajh14>3.0.co;2-e

Activation of the sphingomyelin cycle by brefeldin A: effects of brefeldin A on differentiation and implications for a role for ceramide in regulation of protein trafficking.

The sphingomyelin (SM) cycle is an emerging pathway of signal transduction that plays a role in the control of cell growth, cell differentiation, and apoptosis. During earlier investigation of SM pools hydrolyzed in the SM cycle, we examined the effects of the fungal macrolide brefeldin A (BFA) on cellular levels of SM in HL-60 leukemia cells. We found that BFA induced up to 20-25% hydrolysis of SM. Here we show that this BFA-sensitive SM pool corresponds to the pool of SM hydrolyzed by a previously discovered activator of the SM cycle, 1,25-dihydroxyvitamin D3. BFA was also able to induce the biological end points of SM cycle activation: growth inhibition and differentiation. Reciprocally, ceramide inhibited the secretion of 35S-labeled proteins from HL-60 cells and induced a subset of effects of BFA on organelle morphology. Since a ceramide-activated protein phosphatase has been previously suggested as a direct in vitro target of ceramide action, the effects of modulators of protein kinases and phosphatases were examined. Okadaic acid enhanced protein secretion and was able to oppose the effects of both ceramide and BFA on organelle morphology. Dioctanoylglycerol and phorbol myristate acetate, known activators of protein kinase C, were also found to oppose the inhibitory actions of ceramide on secretion. These studies identify BFA as an activator of the SM cycle, with ceramide as a potential mediator of some of the effects of BFA. Additionally, taken with the effects of the PKC activators, these studies suggest that constitutive protein secretion is not a default pathway but is subject to regulation by processes of signal transduction.

Authors
Linardic, CM; Jayadev, S; Hannun, YA
MLA Citation
Linardic, CM, Jayadev, S, and Hannun, YA. "Activation of the sphingomyelin cycle by brefeldin A: effects of brefeldin A on differentiation and implications for a role for ceramide in regulation of protein trafficking." Cell Growth Differ 7.6 (June 1996): 765-774.
PMID
8780890
Source
pubmed
Published In
Cell growth & differentiation : the molecular biology journal of the American Association for Cancer Research
Volume
7
Issue
6
Publish Date
1996
Start Page
765
End Page
774

Acquired hypoprothrombinemia: Effects of Danazol® treatment

The lupus anticoagulant may be accompanied by an acquired factor II deficiency and bleeding. We report on a patient with a lupus anticoagulant and factor II (FII) deficiency responsive to Danazol®. Acquired hypoprothrombinemia (FII) with the lupus anticoagulant (LA) may be accompanied by a hemorrhagic diathesis. A 64-year-old male with discoid lupus erythematosis bled after an intestinal polypectomy. His FII level was 18%, and his FII antigen level was 20%. Danazol® (D) (600 mg per day) administration was associated with a rise in FII activity and antigen to 50% within 10 days. The patient underwent abdominal surgery. We studied the effect(s) of D on the FII level and on other coagulation factors in this patient. The patient's plasma FII antigen had a single precipitin arc compared to the two peaks of normal plasma on counter immunoelectrophoresis with Ca++. The samples pre- and during D therapy had the same positively charged arc as normal samples, although they were quantitatively different. Neuraminidase treatment demonstrated a decrease in the positively charged migration of normal and the patient's FII antigen. Affinity chromatography of normal and patient plasma on a Sepharose protein A column revealed FII antigen present in the patient's bound fraction. The relative percentages of bound FII before and during D treatment were similar. During D therapy, levels of FIX and X rose 50-100%, and protein C rose 20-25%, while free protein S did not change. D is an effective therapy for acquired FII deficiency associated with LA. D does not affect the binding of Ig to FII, but D raises FII levels by increasing synthesis of the FII protein.

Authors
Williams, S; Linardic, C; Wilson, O; Comp, P; Gralnick, HR
MLA Citation
Williams, S, Linardic, C, Wilson, O, Comp, P, and Gralnick, HR. "Acquired hypoprothrombinemia: Effects of Danazol® treatment." American Journal of Hematology 53.4 (1996): 272-276.
Source
scival
Published In
American Journal of Hematology
Volume
53
Issue
4
Publish Date
1996
Start Page
272
End Page
276
DOI
10.1002/(SICI)1096-8652(199612)53:4<272::AID-AJH14>3.0.CO;2-E

Identification of a distinct pool of sphingomyelin involved in the sphingomyelin cycle.

Sphingomyelin (SM) is a membrane phosphosphingolipid that has recently been identified as a key component of the SM cycle. In this signal transduction pathway, extracellular inducers such as tumor necrosis factor alpha cause hydrolysis of membrane SM, resulting in the generation of the lipid second messenger ceramide. Only 10-20% of cellular SM appears to be involved in the SM cycle, raising the possibility of the existence of a unique "signaling" pool of SM. The existence and subcellular location of such a pool were investigated. Using bacterial sphingomyelinase from Staphylococcus aureus (bSMase), we first characterized two pools of SM, identified as an outer leaflet bSMase-sensitive pool and a distinct bSMase-resistant pool. These pools were further characterized by their differential solubility in Triton X-100 and by their kinetics of labeling. The signaling pool of SM was distinguished by the following: 1) resistance to bSMase, 2) solubility in Triton X-100, and 3) delayed labeling kinetics. In subfractionation studies, the signaling pool of SM co-fractionated with the plasma membrane. Since the SM cycle involves a cytosolic sphingomyelinase and the intracellular release of choline phosphate, this pool of SM appears to localize to the inner leaflet of the plasma membrane (or to a closely related compartment). These results identify a unique signaling pool of SM that undergoes significant hydrolysis (20-40%) in response to inducers of the SM cycle.

Authors
Linardic, CM; Hannun, YA
MLA Citation
Linardic, CM, and Hannun, YA. "Identification of a distinct pool of sphingomyelin involved in the sphingomyelin cycle." J Biol Chem 269.38 (September 23, 1994): 23530-23537.
PMID
8089120
Source
pubmed
Published In
The Journal of biological chemistry
Volume
269
Issue
38
Publish Date
1994
Start Page
23530
End Page
23537

Identification of arachidonic acid as a mediator of sphingomyelin hydrolysis in response to tumor necrosis factor alpha.

A sphingomyelin (SM)-signaling cycle has been described in human leukemia-derived HL-60 cells (Okazaki, T., Bell, R.M., and Hannun, Y.A. (1989) J. Biol. Chem. 264, 19076-19080). Activation of the cycle by tumor necrosis factor alpha (TNF alpha) occurs rapidly, with peak levels of approximately 30% SM hydrolysis observed within 45-60 min. The mechanisms by which TNF alpha induces this SM turnover remain largely unexplored. In this study, arachidonic acid (AA) was investigated as a potential mediator of TNF alpha effects on SM turnover. In HL-60 cells, 30 nM TNF alpha stimulated the release of AA within 5-10 min. In turn, AA stimulated SM hydrolysis and concomitant ceramide generation within 20 min of addition to cells. Other fatty acids, notably oleate, mimicked the effects of AA on SM hydrolysis, but the methyl ester and alcohol analogs of fatty acids were inactive. Diacylglycerol, a candidate mediator of TNF alpha responses, AA activated a cytosolic sphingomyelinase dose dependently, with 10-100 microM AA including 3-4-fold activation, thus suggesting a direct effect of AA on sphingomyelinase. Melittin, a potent phospholipase A2 activator, induced SM hydrolysis at concentrations as low as 35 nM. However, unlike AA, melittin was unable to stimulate sphingomyelinase activation in an in vitro assay system. Finally, exogenous addition of AA also produced antiproliferative effects reminiscent of ceramide effects. Thus, a role for the phospholipase A2/AA pathway in mediating TNF alpha induction of the SM cycle is supported by multiple lines of evidence. These studies begin to elucidate a mechanism of TNF alpha signaling and identify a close relationship between glycerophospholipid and sphingolipid signaling. AA, therefore, may be pivotal to understanding the sphingomyelin-signaling cascade.

Authors
Jayadev, S; Linardic, CM; Hannun, YA
MLA Citation
Jayadev, S, Linardic, CM, and Hannun, YA. "Identification of arachidonic acid as a mediator of sphingomyelin hydrolysis in response to tumor necrosis factor alpha." J Biol Chem 269.8 (February 25, 1994): 5757-5763.
PMID
8119915
Source
pubmed
Published In
The Journal of biological chemistry
Volume
269
Issue
8
Publish Date
1994
Start Page
5757
End Page
5763

Sphingolipid breakdown products: anti-proliferative and tumor-suppressor lipids.

The sphingolipids are a family of lipids found ubiquitously in eukaryotic cell membranes. Within the last decade sphingolipids have emerged as active participants in the regulation of cell growth, differentiation, transformation, and cell-cell contact. A prototypic sphingolipid signalling pathway is the 'sphingomyelin cycle,' in which membrane sphingomyelin is hydrolyzed in response to extracellular stimuli, generating the putative second messenger ceramide. Ceramide, in turn, is thought to propagate the signal into the cell interior by the activation of a phosphatase. It is likely that other sphingolipids are components of similar signalling cycles, generating a variety of lipid messengers which participate in as yet undefined pathways. Sphingosine, for example, is a potential breakdown product of all sphingolipids, and is well-known for its pharmacologic inhibition of protein kinase C. However, it is becoming apparent that sphingosine is active in multiple signalling cascades that are independent of protein kinase C, including effects on fibroblast cell growth and the regulation of the retinoblastoma tumor suppressor protein. Similarly, lyso-sphingolipids, while comprising only a minor fraction of the cell's total sphingolipids, are turning out to have biological effects which warrant their investigation as potential signalling molecules. A distinguishing characteristic of sphingolipid breakdown products is their apparent participation in anti-proliferative pathways of cell regulation. Thus, sphingolipid breakdown products can be found to play roles in growth inhibition, induction of differentiation, and programmed cell death. In coordination with other cellular signal transduction pathways, the sphingolipid breakdown products may be the harnesses on cell growth and may also contribute to the suppression of oncogenesis.

Authors
Hannun, YA; Linardic, CM
MLA Citation
Hannun, YA, and Linardic, CM. "Sphingolipid breakdown products: anti-proliferative and tumor-suppressor lipids." Biochim Biophys Acta 1154.3-4 (December 21, 1993): 223-236. (Review)
PMID
8280742
Source
pubmed
Published In
Biochimica et Biophysica Acta: international journal of biochemistry and biophysics
Volume
1154
Issue
3-4
Publish Date
1993
Start Page
223
End Page
236

ARACHIDONIC-ACID MAY MEDIATE TUMOR-NECROSIS-FACTOR ALPHA-STIMULATED SPHINGOMYELIN HYDROLYSIS

Authors
JAYADEV, S; LINARDIC, CM; HANNUN, YA
MLA Citation
JAYADEV, S, LINARDIC, CM, and HANNUN, YA. "ARACHIDONIC-ACID MAY MEDIATE TUMOR-NECROSIS-FACTOR ALPHA-STIMULATED SPHINGOMYELIN HYDROLYSIS." FASEB JOURNAL 7.7 (April 20, 1993): A1257-A1257.
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
A1257
End Page
A1257

PROGRAMMED CELL-DEATH IS MEDIATED BY CERAMIDE

Authors
OBEID, LM; LINARDIC, CM; KAROLAK, L; HANNUN, YA
MLA Citation
OBEID, LM, LINARDIC, CM, KAROLAK, L, and HANNUN, YA. "PROGRAMMED CELL-DEATH IS MEDIATED BY CERAMIDE." CLINICAL RESEARCH 41.2 (April 1993): A240-A240.
Source
wos-lite
Published In
Clinical Research
Volume
41
Issue
2
Publish Date
1993
Start Page
A240
End Page
A240

LOCALIZATION OF TNF-ALPHA-INDUCED SPHINGOMYELIN HYDROLYSIS TO THE PLASMA-MEMBRANE

Authors
LINARDIC, CM; HANNUN, YA
MLA Citation
LINARDIC, CM, and HANNUN, YA. "LOCALIZATION OF TNF-ALPHA-INDUCED SPHINGOMYELIN HYDROLYSIS TO THE PLASMA-MEMBRANE." CLINICAL RESEARCH 41.2 (April 1993): A240-A240.
Source
wos-lite
Published In
Clinical Research
Volume
41
Issue
2
Publish Date
1993
Start Page
A240
End Page
A240

Programmed cell death induced by ceramide.

Sphingomyelin hydrolysis and ceramide generation have been implicated in a signal transduction pathway that mediates the effects of tumor necrosis factor-alpha (TNF-alpha) and other agents on cell growth and differentiation. In many leukemic cells, TNF-alpha causes DNA fragmentation, which leads to programmed cell death (apoptosis). C2-ceramide (0.6 to 5 microM), a synthetic cell-permeable ceramide analog, induced internucleosomal DNA fragmentation, which was inhibited by zinc ion. Other amphiphilic lipids failed to induce apoptosis. The closely related C2-dihydroceramide was also ineffective, which suggests a critical role for the sphingolipid double bond. The effects of C2-ceramide on DNA fragmentation were prevented by the protein kinase C activator phorbol 12-myristate 13-acetate, which suggests the existence of two opposing intracellular pathways in the regulation of apoptosis.

Authors
Obeid, LM; Linardic, CM; Karolak, LA; Hannun, YA
MLA Citation
Obeid, LM, Linardic, CM, Karolak, LA, and Hannun, YA. "Programmed cell death induced by ceramide." Science 259.5102 (March 19, 1993): 1769-1771.
PMID
8456305
Source
pubmed
Published In
Science
Volume
259
Issue
5102
Publish Date
1993
Start Page
1769
End Page
1771

Ceramide-mediated biology. Determination of structural and stereospecific requirements through the use of N-acyl-phenylaminoalcohol analogs.

Ceramide is a postulated intracellular modulator of cell growth and differentiation (Okazaki, T., Bielawska, A., Bell, R.M., and Hannun, Y. A. (1990) J. Biol. Chem. 265, 15823-15831). In order to determine the structural and stereospecific requirements for ceramide effects on HL-60 cells, N-acyl-phenylaminoalcohol analogs were synthesized and evaluated for their ability to mimic the effects of ceramide on cell proliferation and differentiation. These compounds share with ceramide a similar polar headgroup that allows the investigation of the roles of the primary and secondary hydroxyls, the hydrophobicity of the molecule, and stereospecificity. N-Myristoyl derivatives of phenylamino alcohols showed optimal activity over other chain length analogs and were able to mimic the effects of C2-ceramide on cell growth and differentiation. Neither the primary nor the secondary alcohol was necessary for activity, but the amide-linked acyl chain was required. Stereospecificity of action was demonstrated with an enantiomeric pair: D-erythro-N-myristoyl-2-amino-1-phenyl-1-propanol (C14-D-e-APP-1) and L-erythro-N-myristoyl-2-amino-1-phenyl-1-propanol (C14-L-e-APP-1). The D stereoisomer was as effective as C2-ceramide in inhibiting HL-60 cell growth and in inducing cell differentiation, whereas the L enantiomer lacked activity in both assays. These results suggest stereospecific action of ceramide and strongly support a physiologic role for ceramide as an intracellular mediator with primary roles in regulation of cell growth and differentiation.

Authors
Bielawska, A; Linardic, CM; Hannun, YA
MLA Citation
Bielawska, A, Linardic, CM, and Hannun, YA. "Ceramide-mediated biology. Determination of structural and stereospecific requirements through the use of N-acyl-phenylaminoalcohol analogs." J Biol Chem 267.26 (September 15, 1992): 18493-18497.
PMID
1526986
Source
pubmed
Published In
The Journal of biological chemistry
Volume
267
Issue
26
Publish Date
1992
Start Page
18493
End Page
18497

Modulation of cell growth and differentiation by ceramide.

Ceramide has been suggested as an intracellular modulator of cell growth and differentiation [Okazaki, T. et al. (1990) J. Biol. Chem. 265, 15823-15831]. In this study, parameters that modulate the effects of ceramide on HL-60 cell growth and differentiation were examined. A short-chain, cell-permeable analog of ceramide, C2-ceramide, induced differentiation of HL-60 human leukemia cells and inhibited HL-60 growth in a concentration-dependent manner. The potency of C2-ceramide was modulated by the starting cell density such that the concentration of C2-ceramide producing 50% inhibition of cell growth (IC50%) ranged from 2 microM (for cells suspended at 1 x 10(5) cells/ml) to 11 microM (for cells at 8 x 10(5) cells/ml). However, the IC50% showed little variation if the concentration of C2-ceramide was expressed as fmol of C2-ceramide per 10(5) cells. Therefore, the effectiveness of C2-ceramide appeared to be primarily determined by its cellular rather than molar concentration. Binding of C2-ceramide to serum proteins resulted in a 10-fold increase in the IC50%. These results demonstrate that the biologic activity of C2-ceramide is subject to surface dilution kinetics and is sensitive to the presence of lipid-binding proteins. In these properties, ceramide behaves as a prototypic lipid second messenger/intracellular mediator.

Authors
Bielawska, A; Linardic, CM; Hannun, YA
MLA Citation
Bielawska, A, Linardic, CM, and Hannun, YA. "Modulation of cell growth and differentiation by ceramide." FEBS Lett 307.2 (July 28, 1992): 211-214.
PMID
1644175
Source
pubmed
Published In
FEBS Letters
Volume
307
Issue
2
Publish Date
1992
Start Page
211
End Page
214

Brefeldin A promotes hydrolysis of sphingomyelin.

The hydrolysis of sphingomyelin (SM) is a key reaction in the "sphingomyelin cycle," which plays a role in the regulation of cell proliferation and differentiation (Okazaki, T., Bell, R. M., and Hannun, Y. A. (1989) J. Biol. Chem. 264, 19076-19080). SM is produced from endoplasmic reticulum-derived ceramide and is delivered to organelle membranes in a regulated manner, presumably through the same endomembrane trafficking system used for sorting and delivery of proteins. Since brefeldin A (BFA) interferes with this endomembrane trafficking system and thus alters normal membrane and organelle distribution, we investigated the effect of BFA on SM levels in HL-60 leukemia cells. BFA caused a dose-dependent decrease of 20-25% in cellular SM levels, with effects observed at concentrations of BFA as low as 0.10 microgram/ml. BFA effects on SM levels were noted as early as 5 min and were maximal by 20 min, with no further SM hydrolysis observed up to 60 min following treatment with BFA, suggesting the presence of a fixed SM-sensitive pool. BFA did not cause SM hydrolysis at 16 degrees C, a temperature that inhibits the effects of BFA on endomembrane mixing. The very early effects and temperature dependence of BFA-induced SM hydrolysis suggest that the mechanism of hydrolysis may be closely related to endomembrane mixing. These studies are beginning to define important interrelationships between membrane trafficking and topology, SM metabolism, and cell regulation.

Authors
Linardic, CM; Jayadev, S; Hannun, YA
MLA Citation
Linardic, CM, Jayadev, S, and Hannun, YA. "Brefeldin A promotes hydrolysis of sphingomyelin." J Biol Chem 267.21 (July 25, 1992): 14909-14911.
PMID
1634530
Source
pubmed
Published In
The Journal of biological chemistry
Volume
267
Issue
21
Publish Date
1992
Start Page
14909
End Page
14911

BREFELDIN-A CAUSES DECREASES IN CELLULAR SPHINGOMYELIN LEVELS AND INDUCES DIFFERENTIATION OF HL-60 LEUKEMIA-CELLS

Authors
LINARDIC, CM; JAYADEV, S; HANNUN, YA
MLA Citation
LINARDIC, CM, JAYADEV, S, and HANNUN, YA. "BREFELDIN-A CAUSES DECREASES IN CELLULAR SPHINGOMYELIN LEVELS AND INDUCES DIFFERENTIATION OF HL-60 LEUKEMIA-CELLS." CLINICAL RESEARCH 40.2 (April 1992): A169-A169.
Source
wos-lite
Published In
Clinical Research
Volume
40
Issue
2
Publish Date
1992
Start Page
A169
End Page
A169

Identification of sphingomyelin turnover as an effector mechanism for the action of tumor necrosis factor α and γ-interferon: Specific role in cell differentiation

The biochemical signaling mechanisms involved in transducing the effects of tumor necrosis factor α (TNFα)and γ-interferon (γ-IFN) on leukemia cell differentiation are poorly defined. Recent studies established the existence of a sphingomyelin cycle that operates in response to the action of vitamin D3 on HL-60 cells and that may transduce the effects of vitamin D3 on cell differentiation (Okazaki, T., Bell, R., and Hannun, Y. (1989) J. Biol. Chem. 264, 19076-19080). The effects of TNFα and γ-IFN on sphingomyelin turnover were determined, and the specificity and role of sphingomyelin hydrolysis in HL-60 cell differentiation were examined. TNFα caused early and reversible sphingomyelin hydrolysis in HL-60 human promyelocytic leukemia cells with 20% hydrolysis of sphingomyelin at 15 min, 40% hydrolysis at 30-60 min, and return to base line at 2 h. The hydrolyzed sphingomyelin (18 pmol/nmol total phospholipid) was accompanied by the concomitant generation of ceramide (11.2 pmol/ nmol total phospholipid). γ-IFN also caused reversible hydrolysis of sphingomyelin with onset at 1 h and peak effect at 2 h. This sphingomyelin cycle appeared to be specific to the monocytic pathway of HL-60 differentiation, since it was not activated by retinoic acid or dibutyryl cAMP, inducers of granulocytic differentiation, nor with phorbol myristate acetate, an inducer of macrophage-like differentiation. Addition of synthetic ceramide or bacterial sphingomyelinase induced monocytic differentiation of HL-60 cells. Cell-permeable ceramide also caused prompt down-regulation of mRNA for the c-myc protooncogene. The time course of c-myc down-regulation was consistent with the action of ceramide as the mediator of TNFα action. These results suggest that sphingomyelin turnover may be an important signaling mechanism transducing the actions of TNFα and γ-IFN with specific function in cell differentiation.

Authors
Kim, M-Y; Linardic, C; Obeid, L; Hannun, Y
MLA Citation
Kim, M-Y, Linardic, C, Obeid, L, and Hannun, Y. "Identification of sphingomyelin turnover as an effector mechanism for the action of tumor necrosis factor α and γ-interferon: Specific role in cell differentiation." Journal of Biological Chemistry 266.1 (1991): 484-489.
PMID
1845977
Source
scival
Published In
Journal of Biological Chemistry
Volume
266
Issue
1
Publish Date
1991
Start Page
484
End Page
489

INHIBITION OF THE ANTICOAGULANT PROPERTIES OF ANTITHROMBIN-III AND HEPARIN BY FIBRIN

Authors
LINARDIC, CM; GREENBERG, CS
MLA Citation
LINARDIC, CM, and GREENBERG, CS. "INHIBITION OF THE ANTICOAGULANT PROPERTIES OF ANTITHROMBIN-III AND HEPARIN BY FIBRIN." ANNALS OF THE NEW YORK ACADEMY OF SCIENCES 556 (June 7, 1989): 459-461.
Source
wos-lite
Published In
Annals of the New York Academy of Sciences
Volume
556
Publish Date
1989
Start Page
459
End Page
461

Inhibition of the anticoagulant properties of antithrombin III and heparin by fibrin

Authors
Linardic, CM; Greenberg, CS
MLA Citation
Linardic, CM, and Greenberg, CS. "Inhibition of the anticoagulant properties of antithrombin III and heparin by fibrin." Annals of the New York Academy of Sciences 556 (1989): 459-461.
Source
scival
Published In
Annals of the New York Academy of Sciences
Volume
556
Publish Date
1989
Start Page
459
End Page
461
Show More

Research Areas:

  • Adolescent
  • Amino Acid Transport Systems
  • Animals, Genetically Modified
  • Antibiotics, Antineoplastic
  • Apoptosis
  • Arachidonic Acid
  • Base Sequence
  • Binding Sites
  • Calcitriol
  • Carcinogenesis
  • Cattle
  • Cell Cycle
  • Cell Cycle Proteins
  • Cell Differentiation
  • Cell Division
  • Cell Line, Tumor
  • Cell Proliferation
  • Cell Survival
  • Cell Transformation, Neoplastic
  • Cells, Cultured
  • Ceramides
  • Chemokine CXCL12
  • Cyclin D1
  • Cyclin-Dependent Kinase Inhibitor p16
  • DNA-Binding Proteins
  • Enzyme Activation
  • Female
  • Forkhead Transcription Factors
  • Gene Expression Regulation, Neoplastic
  • Humans
  • Intracellular Membranes
  • Membrane Lipids
  • Mice
  • Muscle Neoplasms
  • Muscle, Skeletal
  • Mutation
  • Myoblasts
  • Myoblasts, Skeletal
  • Neoplasms
  • Neoplastic Stem Cells
  • Nuclear Proteins
  • Nucleosomes
  • Oncogene Proteins, Fusion
  • Oxidative Stress
  • Paired Box Transcription Factors
  • Phosphorylation
  • Promoter Regions, Genetic
  • Protein Kinase C
  • Protein Kinase Inhibitors
  • Protein Kinases
  • Proto-Oncogene Proteins c-myc
  • Recombinant Fusion Proteins
  • Retinoblastoma Protein
  • Rhabdomyosarcoma
  • Rhabdomyosarcoma, Embryonal
  • Signal Transduction
  • Sirolimus
  • Sphingolipids
  • Sphingomyelin Phosphodiesterase
  • Sphingomyelins
  • Stereoisomerism
  • TOR Serine-Threonine Kinases
  • Telomerase
  • Tetradecanoylphorbol Acetate
  • Transcription Factors
  • Transcription, Genetic
  • Transcriptome
  • Transfection
  • Tumor Cells, Cultured
  • Tumor Markers, Biological
  • Tumor Necrosis Factor-alpha
  • Tumor Suppressor Protein p53
  • Vascular Endothelial Growth Factor Receptor-1
  • Xenograft Model Antitumor Assays
  • Zinc
  • ras Proteins