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Chandramohan, Vidyalakshmi

Positions:

Assistant Professor in Neurosurgery

Neurosurgery
School of Medicine

Member of the Duke Cancer Institute

Duke Cancer Institute
School of Medicine

Education:

Ph.D. 2006

Ph.D. — Boston University

Postdoctoral Associate, Surgery

Duke University School of Medicine

Research Associate, Pathology

Duke University School of Medicine

Research Associate, Sr, Pathology

Duke University School of Medicine

Grants:

Oncolytic Polovirus, Immunotoxin, and Checkpoint Inhibitor Therapy of Gliomas

Administered By
Pathology
AwardedBy
National Institutes of Health
Role
Co Investigator
Start Date
August 01, 2015
End Date
July 31, 2022

A Genetically Modified Poliovirus and Immunotoxin for Malignant Brain Tumors

Administered By
Neurosurgery, Neuro-Oncology Clinical Research
AwardedBy
Brain Tumor Research Charity
Role
Investigator
Start Date
December 30, 2013
End Date
December 29, 2017

Determining the maximum tolerated dose of a recombinant immunotoxin targeting wildtype EGFR and Mutant EGFRvIII

Administered By
Neurosurgery, Neuro-Oncology Clinical Research
AwardedBy
Uncle Kory Foundation
Role
Co Investigator
Start Date
November 01, 2016
End Date
October 31, 2017

Immunosequencing of poliovirus and immunotoxin treated brain tumor samples

Administered By
Pathology
AwardedBy
Uncle Kory Foundation
Role
Co Investigator
Start Date
December 01, 2015
End Date
November 30, 2016
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Publications:

Cancer immunotherapy with recombinant poliovirus induces IFN-dominant activation of dendritic cells and tumor antigen-specific CTLs.

Tumors thrive in an immunosuppressive microenvironment that impedes antitumor innate and adaptive immune responses. Thus, approaches that can overcome immunosuppression and engage antitumor immunity are needed. This study defines the adjuvant and cancer immunotherapy potential of the recombinant poliovirus/rhinovirus chimera PVSRIPO. PVSRIPO is currently in clinical trials against recurrent World Health Organization grade IV malignant glioma, a notoriously treatment-refractory cancer. Cytopathogenic infection of neoplastic cells releases the proteome and exposes pathogen- and damage-associated molecular patterns. At the same time, sublethal infection of antigen-presenting cells, such as dendritic cells and macrophages, yields potent, sustained type I interferon-dominant activation in an immunosuppressed microenvironment and promotes the development of tumor antigen-specific T cell responses in vitro and antitumor immunity in vivo. PVSRIPO's immune adjuvancy stimulates canonical innate anti-pathogen inflammatory responses within the tumor microenvironment that culminate in dendritic cell and T cell infiltration. Our findings provide mechanistic evidence that PVSRIPO functions as a potent intratumor immune adjuvant that generates tumor antigen-specific cytotoxic T lymphocyte responses.

Authors
Brown, MC; Holl, EK; Boczkowski, D; Dobrikova, E; Mosaheb, M; Chandramohan, V; Bigner, DD; Gromeier, M; Nair, SK
MLA Citation
Brown, MC, Holl, EK, Boczkowski, D, Dobrikova, E, Mosaheb, M, Chandramohan, V, Bigner, DD, Gromeier, M, and Nair, SK. "Cancer immunotherapy with recombinant poliovirus induces IFN-dominant activation of dendritic cells and tumor antigen-specific CTLs." Science translational medicine 9.408 (September 2017).
PMID
28931654
Source
epmc
Published In
Science Translational Medicine
Volume
9
Issue
408
Publish Date
2017
DOI
10.1126/scitranslmed.aan4220

Production and quality control assessment of a GLP-grade immunotoxin, D2C7-(scdsFv)-PE38KDEL, for a phase I/II clinical trial.

D2C7-(scdsFv)-PE38KDEL (D2C7-IT) is a novel recombinant Pseudomonas exotoxin A-based immunotoxin (IT), targeting both wild-type epidermal growth factor receptor (EGFRwt) and mutant EGFR variant III (EGFRvIII) proteins overexpressed in glioblastomas. Initial pre-clinical testing demonstrated the anti-tumor efficacy of D2C7-IT against orthotopic glioblastoma xenograft models expressing EGFRwt, EGFRvIII, or both EGFRwt and EGFRvIII. A good laboratory practice (GLP) manufacturing process was developed to produce sufficient material for a phase I/II clinical trial. D2C7-IT was expressed under the control of the T7 promoter in Escherichia coli BLR (λ DE3). D2C7-IT was produced by a 10-L batch fermentation process and was then purified from inclusion bodies using anion exchange, size exclusion, and an endotoxin removal process that achieved a yield of over 300 mg of purified protein. The final vialed batch of D2C7-IT for clinical testing was at a concentration of 0.12 ± 0.1 mg/mL, the pH was at 7.4 ± 0.4, and endotoxin levels were below the detection limit of 10 EU/mL (1.26 EU/mL). The stability of the vialed D2C7-IT has been monitored over a period of 42 months through protein concentration, sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), isoelectric focusing, size exclusion chromatography, cytotoxicity, sterility, and pH measurements. The vialed D2C7-IT is currently being tested in a phase I/II clinical trial by intratumoral convection-enhanced delivery for 72 h in patients with recurrent glioblastoma (NCT02303678, D2C7 for Adult Patients with Recurrent Malignant Glioma; clinicaltrials.gov ).

Authors
Chandramohan, V; Pegram, CN; Piao, H; Szafranski, SE; Kuan, C-T; Pastan, IH; Bigner, DD
MLA Citation
Chandramohan, V, Pegram, CN, Piao, H, Szafranski, SE, Kuan, C-T, Pastan, IH, and Bigner, DD. "Production and quality control assessment of a GLP-grade immunotoxin, D2C7-(scdsFv)-PE38KDEL, for a phase I/II clinical trial." Applied microbiology and biotechnology 101.7 (April 2017): 2747-2766.
PMID
28013405
Source
epmc
Published In
Applied Microbiology and Biotechnology
Volume
101
Issue
7
Publish Date
2017
Start Page
2747
End Page
2766
DOI
10.1007/s00253-016-8063-x

Immunotoxin Therapy for Brain Tumors

© 2017 Elsevier Inc. All rights reserved. Despite a multimodal approach involving surgery, radiotherapy, and chemotherapy, the median survival for malignant brain tumor patients is limited to 15-19. months. To improve glioblastoma patient survival, novel therapies targeting the heterogeneous tumor cell population are needed. Advances in understanding the molecular features of patients' tumors have led to the development of personalized tumor-targeted therapies that are more effective and less toxic. Immunotoxins, a novel class of antibody/ligand-toxin conjugates, have been developed during the last two decades for the treatment of brain tumors. The antibody/ligand domain of the immunotoxin binds to the target antigen on the tumor cell surface, whereas the toxin payload kills the tumor cells by inhibiting protein synthesis. Advances in immunotoxin delivery and monitoring of immunotoxin distribution in tumors are overcoming the challenges in the brain tumor therapy field. Herein, we summarize the different antiglioma immunotoxins that are at the preclinical and clinical stages of development.

Authors
Chandramohan, V; Sampson, JH; Pastan, IH; Bigner, DD
MLA Citation
Chandramohan, V, Sampson, JH, Pastan, IH, and Bigner, DD. "Immunotoxin Therapy for Brain Tumors." Translational Immunotherapy of Brain Tumors. March 2, 2017. 227-260.
Source
scopus
Publish Date
2017
Start Page
227
End Page
260
DOI
10.1016/B978-0-12-802420-1.00010-7

Preclinical Immunotherapeutic Animal Models for Brain Tumors

© 2017 Elsevier Inc. All rights reserved. Glioblastoma (GBM) is the most malignant primary brain tumor in adults. Even with the current standard of care therapy (i.e., surgery, radiotherapy, and chemotherapy), GBM has a poor prognosis. Innovative immunotherapeutic approaches, which engage a patient's immune system to trigger a tumor-specific immune response, have generated modest clinical improvements in selected GBM patient populations. Patients with GBM demonstrate extensive systemic immune defects that deter the efficacy of both conventional and immune-based treatments. Therapeutic strategies that simultaneously activate the immune system and neutralize the immunosuppression are critical for enhancing treatment outcomes in GBM patients. Owing to the essential role of the immune system in tumor eradication, preclinical animal models recapitulating the human disease in immunocompetent hosts are vital for assessing the efficacy of anti-GBM experimental therapies prior to testing in patients. Different immunocompetent animal models available in the preclinical setting for the evaluation of novel brain tumor therapies are summarized in this chapter.

Authors
Chandramohan, V; Sanchez-Perez, L; He, Y; Pirozzi, CJ; Congdon, KL; Bigner, DD
MLA Citation
Chandramohan, V, Sanchez-Perez, L, He, Y, Pirozzi, CJ, Congdon, KL, and Bigner, DD. "Preclinical Immunotherapeutic Animal Models for Brain Tumors." Translational Immunotherapy of Brain Tumors. March 2, 2017. 111-147.
Source
scopus
Publish Date
2017
Start Page
111
End Page
147
DOI
10.1016/B978-0-12-802420-1.00006-5

Development and validation of a cell-based fluorescent method for measuring antibody affinity.

Monoclonal antibodies have become essential tools for diagnostic and therapeutic purposes. Antibody affinity is one of the critical factors influencing the therapeutic success of tumor-targeting antibodies. Therefore, developing an accurate and reliable method for determining antibody affinity is crucial. In this study, we describe a fluorescent cell-based immunosorbent assay that can accurately measure antibody affinity (KD) in the nanomolar range. This method involves the addition of fluorescently labeled antibodies to antigen-positive and antigen-negative cell lines fixed on 96-well plates. The fluorescent signals from nonspecific binding to negative control cell lines is subtracted from the specific binding to the antigen-positive cell lines. The KD values obtained by this method were comparable with values obtained by the flow cytometry and radioactive (I125) scatchard assay. Our results demonstrate that this modified cell-based fluorescent method allows for a convenient and efficient identification of therapeutically relevant leads.

Authors
Yu, X; Pegram, CN; Bigner, DD; Chandramohan, V
MLA Citation
Yu, X, Pegram, CN, Bigner, DD, and Chandramohan, V. "Development and validation of a cell-based fluorescent method for measuring antibody affinity." Journal of immunological methods 442 (March 2017): 49-53.
PMID
28024998
Source
epmc
Published In
Journal of Immunological Methods
Volume
442
Publish Date
2017
Start Page
49
End Page
53
DOI
10.1016/j.jim.2016.12.004

Preclinical toxicity evaluation of a novel immunotoxin, D2C7-(scdsFv)-PE38KDEL, administered via intracerebral convection-enhanced delivery in rats.

D2C7-(scdsFv)-PE38KDEL (D2C7-IT) is a novel immunotoxin that reacts with wild-type epidermal growth factor receptor (EGFRwt) and mutant EGFRvIII proteins overexpressed in glioblastomas. This study assessed the toxicity of intracerebral administration of D2C7-IT to support an initial Food and Drug Administration Investigational New Drug application. After the optimization of the formulation and administration, two cohorts (an acute and chronic cohort necropsied on study days 5 and 34) of Sprague-Dawley (SD) rats (four groups of 5 males and 5 females) were infused with the D2C7-IT formulation at total doses of 0, 0.05, 0.1, 0.4 μg (the acute cohort) and 0, 0.05, 0.1, 0.35 μg (the chronic cohort) for approximately 72 h by intracerebral convection-enhanced delivery using osmotic pumps. Mortality was observed in the 0.40 μg (5/10 rats) and 0.35 μg (4/10 rats) high-dose groups of each cohort. Body weight loss and abnormal behavior were only revealed in the rats treated with high doses of D2C7-IT. No dose-related effects were observed in clinical laboratory tests in either cohort. A gross pathologic examination of systemic tissues from the high-dose and control groups in both cohorts exhibited no dose-related or drug-related pathologic findings. Brain histopathology revealed the frequent occurrence of dose-related encephalomalacia, edema, and demyelination in the high-dose groups of both cohorts. In this study, the maximum tolerated dose of D2C7-IT was determined to be between 0.10 and 0.35 μg, and the no-observed-adverse-effect-level was 0.05 μg in SD rats. Both parameters were utilized to design the Phase I/II D2C7-IT clinical trial.

Authors
Bao, X; Chandramohan, V; Reynolds, RP; Norton, JN; Wetsel, WC; Rodriguiz, RM; Aryal, DK; McLendon, RE; Levin, ED; Petry, NA; Zalutsky, MR; Burnett, BK; Kuan, C-T; Pastan, IH; Bigner, DD
MLA Citation
Bao, X, Chandramohan, V, Reynolds, RP, Norton, JN, Wetsel, WC, Rodriguiz, RM, Aryal, DK, McLendon, RE, Levin, ED, Petry, NA, Zalutsky, MR, Burnett, BK, Kuan, C-T, Pastan, IH, and Bigner, DD. "Preclinical toxicity evaluation of a novel immunotoxin, D2C7-(scdsFv)-PE38KDEL, administered via intracerebral convection-enhanced delivery in rats." Investigational new drugs 34.2 (April 2016): 149-158.
PMID
26728879
Source
epmc
Published In
Investigational New Drugs
Volume
34
Issue
2
Publish Date
2016
Start Page
149
End Page
158
DOI
10.1007/s10637-015-0318-3

CAR T Cells Targeting Podoplanin Reduce Orthotopic Glioblastomas in Mouse Brains.

Glioblastoma (GBM) is the most common and lethal primary malignant brain tumor in adults with a 5-year overall survival rate of less than 10%. Podoplanin (PDPN) is a type I transmembrane mucin-like glycoprotein, expressed in the lymphatic endothelium. Several solid tumors overexpress PDPN, including the mesenchymal type of GBM, which has been reported to present the worst prognosis among GBM subtypes. Chimeric antigen receptor (CAR)-transduced T cells can recognize predefined tumor surface antigens independent of MHC restriction, which is often downregulated in gliomas. We constructed a lentiviral vector expressing a third-generation CAR comprising a PDPN-specific antibody (NZ-1-based single-chain variable fragment) with CD28, 4-1BB, and CD3ζ intracellular domains. CAR-transduced peripheral blood monocytes were immunologically evaluated by calcein-mediated cytotoxic assay, ELISA, tumor size, and overall survival. The generated CAR T cells were specific and effective against PDPN-positive GBM cells in vitro. Systemic injection of the CAR T cells into an immunodeficient mouse model inhibited the growth of intracranial glioma xenografts in vivo. CAR T-cell therapy that targets PDPN would be a promising adoptive immunotherapy to treat mesenchymal GBM.

Authors
Shiina, S; Ohno, M; Ohka, F; Kuramitsu, S; Yamamichi, A; Kato, A; Motomura, K; Tanahashi, K; Yamamoto, T; Watanabe, R; Ito, I; Senga, T; Hamaguchi, M; Wakabayashi, T; Kaneko, MK; Kato, Y; Chandramohan, V; Bigner, DD; Natsume, A
MLA Citation
Shiina, S, Ohno, M, Ohka, F, Kuramitsu, S, Yamamichi, A, Kato, A, Motomura, K, Tanahashi, K, Yamamoto, T, Watanabe, R, Ito, I, Senga, T, Hamaguchi, M, Wakabayashi, T, Kaneko, MK, Kato, Y, Chandramohan, V, Bigner, DD, and Natsume, A. "CAR T Cells Targeting Podoplanin Reduce Orthotopic Glioblastomas in Mouse Brains." Cancer immunology research 4.3 (March 2016): 259-268.
PMID
26822025
Source
epmc
Published In
Cancer Immunology Research
Volume
4
Issue
3
Publish Date
2016
Start Page
259
End Page
268
DOI
10.1158/2326-6066.cir-15-0060

Induction of viral, 7-methyl-guanosine cap-independent translation and oncolysis by mitogen-activated protein kinase-interacting kinase-mediated effects on the serine/arginine-rich protein kinase.

Protein synthesis, the most energy-consuming process in cells, responds to changing physiologic priorities, e.g., upon mitogen- or stress-induced adaptations signaled through the mitogen-activated protein kinases (MAPKs). The prevailing status of protein synthesis machinery is a viral pathogenesis factor, particularly for plus-strand RNA viruses, where immediate translation of incoming viral RNAs shapes host-virus interactions. In this study, we unraveled signaling pathways centered on the ERK1/2 and p38α MAPK-interacting kinases MNK1/2 and their role in controlling 7-methyl-guanosine (m(7)G) "cap"-independent translation at enterovirus type 1 internal ribosomal entry sites (IRESs). Activation of Raf-MEK-ERK1/2 signals induced viral IRES-mediated translation in a manner dependent on MNK1/2. This effect was not due to MNK's known functions as eukaryotic initiation factor (eIF) 4G binding partner or eIF4E(S209) kinase. Rather, MNK catalytic activity enabled viral IRES-mediated translation/host cell cytotoxicity through negative regulation of the Ser/Arg (SR)-rich protein kinase (SRPK). Our investigations suggest that SRPK activity is a major determinant of type 1 IRES competency, host cell cytotoxicity, and viral proliferation in infected cells.We are targeting unfettered enterovirus IRES activity in cancer with PVSRIPO, the type 1 live-attenuated poliovirus (PV) (Sabin) vaccine containing a human rhinovirus type 2 (HRV2) IRES. A phase I clinical trial of PVSRIPO with intratumoral inoculation in patients with recurrent glioblastoma (GBM) is showing early promise. Viral translation proficiency in infected GBM cells is a core requirement for the antineoplastic efficacy of PVSRIPO. Therefore, it is critically important to understand the mechanisms controlling viral cap-independent translation in infected host cells.

Authors
Brown, MC; Bryant, JD; Dobrikova, EY; Shveygert, M; Bradrick, SS; Chandramohan, V; Bigner, DD; Gromeier, M
MLA Citation
Brown, MC, Bryant, JD, Dobrikova, EY, Shveygert, M, Bradrick, SS, Chandramohan, V, Bigner, DD, and Gromeier, M. "Induction of viral, 7-methyl-guanosine cap-independent translation and oncolysis by mitogen-activated protein kinase-interacting kinase-mediated effects on the serine/arginine-rich protein kinase." Journal of virology 88.22 (November 2014): 13135-13148.
PMID
25187541
Source
epmc
Published In
Journal of virology
Volume
88
Issue
22
Publish Date
2014
Start Page
13135
End Page
13148
DOI
10.1128/jvi.01883-14

A novel recombinant immunotoxin-based therapy targeting wild-type and mutant EGFR improves survival in murine models of glioblastoma

Both the amplification of the gene coding for wild-type (wt) epidermal growth factor receptor (EGFR) and the overexpression of the EGFR deletion mutant, commonly known as EGFRvIII, are hallmarks of glioblastoma. We have recently reported a novel, recombinant immunotoxin, D2C7-(scdsFv)-PE38KDEL, that targets both wt EGFR and EGFRvIII, exhibiting potent antineoplastic effects against established murine gliomas. © 2013 Landes Bioscience.

Authors
Chandramohan, V; Bigner, DD
MLA Citation
Chandramohan, V, and Bigner, DD. "A novel recombinant immunotoxin-based therapy targeting wild-type and mutant EGFR improves survival in murine models of glioblastoma." OncoImmunology 2.12 (December 1, 2013): 1-2.
Source
scopus
Published In
OncoImmunology
Volume
2
Issue
12
Publish Date
2013
Start Page
1
End Page
2
DOI
10.4161/onci.26852

Construction of an immunotoxin, D2C7-(scdsFv)-PE38KDEL, targeting EGFRwt and EGFRvIII for brain tumor therapy.

PURPOSE: The EGF receptor gene (EGFR) is most frequently amplified and overexpressed, along with its deletion mutant, EGFRvIII, in glioblastoma. We tested the preclinical efficacy of the recombinant immunotoxin, D2C7-(scdsFv)-PE38KDEL, which is reactive with a 55-amino acid (AA) region present in the extracellular domain of both EGFRwt (583-637 AAs) and EGFRvIII (292-346 AAs) proteins. EXPERIMENTAL DESIGN: The binding affinity and specificity of D2C7-(scdsFv)-PE38KDEL for EGFRwt and EGFRvIII were measured by surface-plasmon resonance and flow cytometry. In vitro cytotoxicity of D2C7-(scdsFv)-PE38KDEL was measured by inhibition of protein synthesis in human EGFRwt-transfected NR6 (NR6W), human EGFRvIII-transfected NR6 (NR6M), EGFRwt-overexpressing A431-epidermoid-carcinoma, and glioblastoma xenograft cells (43, D08-0493MG, D2159MG, and D270MG). In vivo antitumor efficacy of D2C7-(scdsFv)-PE38KDEL was evaluated using 43, NR6M, and D270MG orthotopic tumor models. RESULTS: The KD of D2C7-(scdsFv)-PE38KDEL for EGFRwt and EGFRvIII was 1.6×10(-9) mol/L and 1.3×10(-9) mol/L, respectively. Flow cytometry with NR6W and NR6M cells confirmed the specificity of D2C7-(scdsFv)-PE38KDEL for EGFRwt and EGFRvIII. The D2C7-(scdsFv)-PE38KDEL IC50 was 0.18 to 2.5 ng/mL on cells expressing EGFRwt (NR6W, A431, 43, and D08-0493MG). The D2C7-(scdsFv)-PE38KDEL IC50 was approximately 0.25 ng/mL on EGFRvIII-expressing cells (NR6M) and on EGFRwt- and EGFRvIII-expressing glioblastoma xenograft cells (D2159MG and D270MG). Significantly, in intracranial tumor models of 43, NR6M, and D270MG, treatment with D2C7-(scdsFv)-PE38KDEL by convection-enhanced delivery prolonged survival by 310% (P=0.006), 28% (P=0.002), and 166% (P=0.001), respectively. CONCLUSIONS: In preclinical studies, the D2C7-(scdsFv)-PE38KDEL immunotoxin exhibited significant potential for treating brain tumors expressing EGFRwt, EGFRvIII, or both.

Authors
Chandramohan, V; Bao, X; Keir, ST; Pegram, CN; Szafranski, SE; Piao, H; Wikstrand, CJ; McLendon, RE; Kuan, C-T; Pastan, IH; Bigner, DD
MLA Citation
Chandramohan, V, Bao, X, Keir, ST, Pegram, CN, Szafranski, SE, Piao, H, Wikstrand, CJ, McLendon, RE, Kuan, C-T, Pastan, IH, and Bigner, DD. "Construction of an immunotoxin, D2C7-(scdsFv)-PE38KDEL, targeting EGFRwt and EGFRvIII for brain tumor therapy." Clin Cancer Res 19.17 (September 1, 2013): 4717-4727.
PMID
23857604
Source
pubmed
Published In
Clinical cancer research : an official journal of the American Association for Cancer Research
Volume
19
Issue
17
Publish Date
2013
Start Page
4717
End Page
4727
DOI
10.1158/1078-0432.CCR-12-3891

Affinity-matured recombinant immunotoxin targeting gangliosides 3'-isoLM1 and 3',6'-isoLD1 on malignant gliomas.

About 60 percent of glioblastomas highly express the gangliosides 3'-isoLM1 and 3',6'-isoLD1 on the cell surface, providing ideal targets for brain tumor immunotherapy. A novel recombinant immunotoxin, DmAb14m-(scFv)-PE38KDEL (DmAb14m-IT), specific for the gangliosides 3'-isoLM1 and 3',6'-isoLD1, was constructed with improved affinity and increased cytotoxicity for immunotherapeutic targeting of glioblastoma. We isolated an scFv parental clone from a previously established murine hybridoma, DmAb14, that is specific to both 3'-isoLM1 and 3',6'-isoLD1. We then performed in vitro affinity maturation by CDR hotspot random mutagenesis. The binding affinity and specificity of affinity-matured DmAb14m-IT were measured by surface-plasmon resonance, flow cytometry, and immunohistochemical analysis. In vitro cytotoxicity of DmAb14m-IT was measured by protein synthesis inhibition and cell death assays in human cell lines expressing gangliosides 3'-isoLM1 and 3',6'-isoLD1 (D54MG and D336MG) and xenograft-derived cells (D2224MG). As a result, the KD of DmAb14m-IT for gangliosides 3'-isoLM1 and 3',6'-isoLD1 was 2.6 × 10(-9)M. Also, DmAb14m-IT showed a significantly higher internalization rate in cells expressing 3'-isoLM1 and 3',6'-isoLD1. The DmAb14m-IT IC 50 was 80 ng/mL (1194 pM) on the D54MG cell line, 5 ng/ml (75 pM) on the D336MG cell line, and 0.5 ng/ml (7.5 pM) on the D2224MG xenograft-derived cells. There was no cytotoxicity on ganglioside-negative HEK293 cells. Immunohistochemical analysis confirmed the specific apparent affinity of DmAb14m-IT with 3'-isoLM1 and 3',6'-isoLD1. In conclusion, DmAb14m-IT showed specific binding affinity, a significantly high internalization rate, and selective cytotoxicity on glioma cell lines and xenograft-derived cells expressing 3'-isoLM1 and 3',6'-isoLD1, thereby displaying robust therapeutic potential for testing the antitumor efficacy of DmAb14m-IT at the preclinical level and eventually in the clinical setting.

Authors
Piao, H; Kuan, C-T; Chandramohan, V; Keir, ST; Pegram, CN; Bao, X; Månsson, J-E; Pastan, IH; Bigner, DD
MLA Citation
Piao, H, Kuan, C-T, Chandramohan, V, Keir, ST, Pegram, CN, Bao, X, Månsson, J-E, Pastan, IH, and Bigner, DD. "Affinity-matured recombinant immunotoxin targeting gangliosides 3'-isoLM1 and 3',6'-isoLD1 on malignant gliomas." MAbs 5.5 (September 2013): 748-762.
PMID
23924792
Source
pubmed
Published In
mAbs
Volume
5
Issue
5
Publish Date
2013
Start Page
748
End Page
762
DOI
10.4161/mabs.25860

Antibody, T-cell and dendritic cell immunotherapy for malignant brain tumors.

Modest improvement in brain tumor patient survival has been achieved through advances in surgical, adjuvant radiation and chemotherapeutic strategies. However, these traditional approaches have been unsuccessful in permanently controlling these aggressive tumors, with recurrence being quite common. Hence, there is a need for novel therapeutic approaches that specifically target the molecularly diverse brain tumor cell population. The ability of the immune system to recognize altered tumor cells while avoiding surrounding normal cells offers an enormous advantage over the nonspecific nature of the conventional treatment schemes. Therefore, immunotherapy represents a promising approach that may supplement the standard therapies in eliminating the residual brain tumor cells. This review summarizes different immunotherapeutic approaches currently being tested for malignant brain tumor treatment.

Authors
Chandramohan, V; Mitchell, DA; Johnson, LA; Sampson, JH; Bigner, DD
MLA Citation
Chandramohan, V, Mitchell, DA, Johnson, LA, Sampson, JH, and Bigner, DD. "Antibody, T-cell and dendritic cell immunotherapy for malignant brain tumors." Future Oncol 9.7 (July 2013): 977-990. (Review)
PMID
23837761
Source
pubmed
Published In
Future oncology (London, England)
Volume
9
Issue
7
Publish Date
2013
Start Page
977
End Page
990
DOI
10.2217/fon.13.47

Recombinant anti-podoplanin (NZ-1) immunotoxin for the treatment of malignant brain tumors.

Our study demonstrates the glioma tumor antigen podoplanin to be present at very high levels (>90%) in both glioblastoma (D2159MG, D08-0308MG and D08-0493MG) and medulloblastoma (D283MED, D425MED and DAOY) xenografts and cell line. We constructed a novel recombinant single-chain antibody variable region fragment (scFv), NZ-1, specific for podoplanin from the NZ-1 hybridoma. NZ-1-scFv was then fused to Pseudomonas exotoxin A, carrying a C-terminal KDEL peptide (NZ-1-PE38KDEL). The immunotoxin (IT) was further stabilized by a disulfide (ds) bond between the heavy-chain and light-chain variable regions as the construct NZ-1-(scdsFv)-PE38KDEL. NZ-1-(scdsFv)-PE38KDEL exhibited significant reactivity to glioblastoma and medulloblastoma cells. The affinity of NZ-1-(scdsFv), NZ-1-(scdsFv)-PE38KDEL and NZ-1 antibody for podoplanin peptide was 2.1 × 10(-8) M, 8.0 × 10(-8) M and 3.9 × 10(-10) M, respectively. In a protein stability assay, NZ-1-(scdsFv)-PE38KDEL retained 33-98% of its activity, whereas that of NZ-1-PE38KDEL declined to 13% of its initial levels after incubation at 37°C for 3 days. In vitro cytotoxicity of the NZ-1-(scdsFv)-PE38KDEL was measured in cells isolated from glioblastoma xenografts, D2159MG, D08-0308MG and D08-0493MG, and in the medulloblastoma D283MED, D425MED and DOAY xenografts and cell line. The NZ-1-(scdsFv)-PE38KDEL IT was highly cytotoxic, with an 50% inhibitory concentration in the range of 1.6-29 ng/ml. Significantly, NZ-1-(scdsFv)-PE38KDEL demonstrated tumor growth delay, averaging 24 days (p < 0.001) and 21 days (p < 0.001) in D2159MG and D283MED in vivo tumor models, respectively. Crucially, in the D425MED intracranial tumor model, NZ-1-(scdsFv)-PE38KDEL caused a 41% increase in survival (p ≤ 0.001). In preclinical studies, NZ-1-(scdsFv)-PE38KDEL exhibited significant potential as a targeting agent for malignant brain tumors.

Authors
Chandramohan, V; Bao, X; Kato Kaneko, M; Kato, Y; Keir, ST; Szafranski, SE; Kuan, C-T; Pastan, IH; Bigner, DD
MLA Citation
Chandramohan, V, Bao, X, Kato Kaneko, M, Kato, Y, Keir, ST, Szafranski, SE, Kuan, C-T, Pastan, IH, and Bigner, DD. "Recombinant anti-podoplanin (NZ-1) immunotoxin for the treatment of malignant brain tumors." Int J Cancer 132.10 (May 15, 2013): 2339-2348.
PMID
23115013
Source
pubmed
Published In
International Journal of Cancer
Volume
132
Issue
10
Publish Date
2013
Start Page
2339
End Page
2348
DOI
10.1002/ijc.27919

Current immunotherapeutic targets in gliomas

The prospect for high-grade astrocytic tumor patients continues to be dismal, evenwith advances in surgery, radiotherapy, and chemotherapy. There is a need for thedevelopment of novel therapies that would eliminate the heterogeneous and diffuseastrocytic tumor cells.Innovative therapeutic approaches for the treatment of central nervous systemneoplasia, such as antibody-mediated immunotherapeutics, cellular immunotherapeutics,and oncolytic viruses targeting tumor-associated antigens, have emerged during the pastfew years.Herein we review several of the glioma-associated antigens and the current status ofimmunotherapeutics and oncolytic viruses targeting these antigens. © 2013 Nova Science Publishers, Inc. All rights reserved.

Authors
Chandramohan, V; Mitchell, DA; Gromeier, M; Sampson, JH; Bigner, DD
MLA Citation
Chandramohan, V, Mitchell, DA, Gromeier, M, Sampson, JH, and Bigner, DD. "Current immunotherapeutic targets in gliomas." (May 1, 2013): 287-305. (Chapter)
Source
scopus
Publish Date
2013
Start Page
287
End Page
305

Recombinant anti-podoplanin (NZ-1) immunotoxin for the treatment of malignant brain tumors

Our study demonstrates the glioma tumor antigen podoplanin to be present at very high levels (>90%) in both glioblastoma (D2159MG, D08-0308MG and D08-0493MG) and medulloblastoma (D283MED, D425MED and DAOY) xenografts and cell line. We constructed a novel recombinant single-chain antibody variable region fragment (scFv), NZ-1, specific for podoplanin from the NZ-1 hybridoma. NZ-1-scFv was then fused to Pseudomonas exotoxin A, carrying a C-terminal KDEL peptide (NZ-1-PE38KDEL). The immunotoxin (IT) was further stabilized by a disulfide (ds) bond between the heavy-chain and light-chain variable regions as the construct NZ-1-(scdsFv)-PE38KDEL. NZ-1-(scdsFv)-PE38KDEL exhibited significant reactivity to glioblastoma and medulloblastoma cells. The affinity of NZ-1-(scdsFv), NZ-1-(scdsFv)-PE38KDEL and NZ-1 antibody for podoplanin peptide was 2.1 × 10-8 M, 8.0 × 10-8 M and 3.9 × 10-10 M, respectively. In a protein stability assay, NZ-1-(scdsFv)-PE38KDEL retained 33-98% of its activity, whereas that of NZ-1-PE38KDEL declined to 13% of its initial levels after incubation at 37°C for 3 days. In vitro cytotoxicity of the NZ-1-(scdsFv)-PE38KDEL was measured in cells isolated from glioblastoma xenografts, D2159MG, D08-0308MG and D08-0493MG, and in the medulloblastoma D283MED, D425MED and DOAY xenografts and cell line. The NZ-1-(scdsFv)-PE38KDEL IT was highly cytotoxic, with an 50% inhibitory concentration in the range of 1.6-29 ng/ml. Significantly, NZ-1-(scdsFv)-PE38KDEL demonstrated tumor growth delay, averaging 24 days (p < 0.001) and 21 days (p < 0.001) in D2159MG and D283MED in vivo tumor models, respectively. Crucially, in the D425MED intracranial tumor model, NZ-1-(scdsFv)-PE38KDEL caused a 41% increase in survival (p ≤ 0.001). In preclinical studies, NZ-1-(scdsFv)-PE38KDEL exhibited significant potential as a targeting agent for malignant brain tumors. What's new? Podoplanin is a glycoprotein that is overexpressed in several types of malignant tumor, including glioblastoma, medulloblastoma, mesothelioma, and germ-cell tumors. In this study, the authors constructed a novel immunotoxin to target podoplanin, by fusing a monoclonal antibody fragment to exotoxin A from Pseudomonas. In preclinical studies, this immunotoxin, called NZ-1-(scdsFv)-PE38KDEL, increased survival by 41%. Its specificity and high binding affinity allow for specific targeting of tumor cells while avoiding adjacent normal tissue, thereby having the potential to improve survival of patients with brain tumors. Copyright © 2012 UICC.

Authors
Chandramohan, V; Bao, X; Kaneko, MK; Kato, Y; Keir, ST; Szafranski, SE; Kuan, C-T; Pastan, IH; Bigner, DD
MLA Citation
Chandramohan, V, Bao, X, Kaneko, MK, Kato, Y, Keir, ST, Szafranski, SE, Kuan, C-T, Pastan, IH, and Bigner, DD. "Recombinant anti-podoplanin (NZ-1) immunotoxin for the treatment of malignant brain tumors." International Journal of Cancer 132.10 (2013): 2339-2348.
Source
scival
Published In
International Journal of Cancer
Volume
132
Issue
10
Publish Date
2013
Start Page
2339
End Page
2348
DOI
10.1002/ijc.27919

Toxin-based targeted therapy for malignant brain tumors.

Despite advances in conventional treatment modalities for malignant brain tumors-surgery, radiotherapy, and chemotherapy-the prognosis for patients with high-grade astrocytic tumor remains dismal. The highly heterogeneous and diffuse nature of astrocytic tumors calls for the development of novel therapies. Advances in genomic and proteomic research indicate that treatment of brain tumor patients can be increasingly personalized according to the characteristics of the targeted tumor and its environment. Consequently, during the last two decades, a novel class of investigative drug candidates for the treatment of central nervous system neoplasia has emerged: recombinant fusion protein conjugates armed with cytotoxic agents targeting tumor-specific antigens. The clinical applicability of the tumor-antigen-directed cytotoxic proteins as a safe and viable therapy for brain tumors is being investigated. Thus far, results from ongoing clinical trials are encouraging, as disease stabilization and patient survival prolongation have been observed in at least 109 cases. This paper summarizes the major findings pertaining to treatment with the different antiglioma cytotoxins at the preclinical and clinical stages.

Authors
Chandramohan, V; Sampson, JH; Pastan, I; Bigner, DD
MLA Citation
Chandramohan, V, Sampson, JH, Pastan, I, and Bigner, DD. "Toxin-based targeted therapy for malignant brain tumors." Clin Dev Immunol 2012 (2012): 480429-. (Review)
PMID
22400035
Source
pubmed
Published In
Clinical & Developmental Immunology (Hindawi)
Volume
2012
Publish Date
2012
Start Page
480429
DOI
10.1155/2012/480429

Evaluation of anti-podoplanin rat monoclonal antibody NZ-1 for targeting malignant gliomas.

INTRODUCTION: Podoplanin/aggrus is a mucin-like sialoglycoprotein that is highly expressed in malignant gliomas. Podoplanin has been reported to be a novel marker to enrich tumor-initiating cells, which are thought to resist conventional therapies and to be responsible for cancer relapse. The purpose of this study was to determine whether an anti-podoplanin antibody is suitable to target radionuclides to malignant gliomas. METHODS: The binding affinity of an anti-podoplanin antibody, NZ-1 (rat IgG(2a)), was determined by surface plasmon resonance and Scatchard analysis. NZ-1 was radioiodinated with (125)I using Iodogen [(125)I-NZ-1(Iodogen)] or N-succinimidyl 4-guanidinomethyl 3-[(131)I]iodobenzoate ([(131)I]SGMIB-NZ-1), and paired-label internalization assays of NZ-1 were performed. The tissue distribution of (125)I-NZ-1(Iodogen) and that of [(131)I]SGMIB-NZ-1 were then compared in athymic mice bearing glioblastoma xenografts. RESULTS: The dissociation constant (K(D)) of NZ-1 was determined to be 1.2 × 10(-10) M by surface plasmon resonance and 9.8 × 10(-10) M for D397MG glioblastoma cells by Scatchard analysis. Paired-label internalization assays in LN319 glioblastoma cells indicated that [(131)I]SGMIB-NZ-1 resulted in higher intracellular retention of radioactivity (26.3 ± 0.8% of initially bound radioactivity at 8 h) compared to that from the (125)I-NZ-1(Iodogen) (10.0 ± 0.1% of initially bound radioactivity at 8 h). Likewise, tumor uptake of [(131)I]SGMIB-NZ-1 (39.9 ± 8.8 %ID/g at 24 h) in athymic mice bearing D2159MG xenografts in vivo was significantly higher than that of (125)I-NZ-1(Iodogen) (29.7 ± 6.1 %ID/g at 24 h). CONCLUSIONS: The overall results suggest that an anti-podoplanin antibody NZ-1 warrants further evaluation for antibody-based therapy against glioblastoma.

Authors
Kato, Y; Vaidyanathan, G; Kaneko, MK; Mishima, K; Srivastava, N; Chandramohan, V; Pegram, C; Keir, ST; Kuan, C-T; Bigner, DD; Zalutsky, MR
MLA Citation
Kato, Y, Vaidyanathan, G, Kaneko, MK, Mishima, K, Srivastava, N, Chandramohan, V, Pegram, C, Keir, ST, Kuan, C-T, Bigner, DD, and Zalutsky, MR. "Evaluation of anti-podoplanin rat monoclonal antibody NZ-1 for targeting malignant gliomas." Nucl Med Biol 37.7 (October 2010): 785-794.
PMID
20870153
Source
pubmed
Published In
Nuclear Medicine and Biology
Volume
37
Issue
7
Publish Date
2010
Start Page
785
End Page
794
DOI
10.1016/j.nucmedbio.2010.03.010

GMab-1, a high-affinity anti-3'-isoLM1/3',6'-isoLD1 IgG monoclonal antibody, raised in lacto-series ganglioside-defective knockout mice.

The lacto-series gangliosides 3'-isoLM1 and 3',6'-isoLD1 have been identified as tumor-associated antigens whose formation is initiated by the Lc3-synthase. Until now, high-affinity IgG monoclonal antibodies (mAbs) against 3'-isoLM1 and 3',6'-isoLD1, which are highly expressed in gliomas, have not been developed, although mAbs against lacto-series gangliosides are powerful tools for functional studies. We previously produced the Lc3-synthase gene beta3Gn-T5 knockout mice. In this study, we immunized beta3Gn-T5 knockout mice with 3'-isoLM1/3',6'-isoLD1 and produced the anti-3'-isoLM1/3',6'-isoLD1 mAb GMab-1, of the IgG(3) subclass, which should be useful for functional analysis of lacto-series gangliosides and for antibody-based therapy of gliomas.

Authors
Kato, Y; Kuan, C-T; Chang, J; Kaneko, MK; Ayriss, J; Piao, H; Chandramohan, V; Pegram, C; McLendon, RE; Fredman, P; Månsson, J-E; Bigner, DD
MLA Citation
Kato, Y, Kuan, C-T, Chang, J, Kaneko, MK, Ayriss, J, Piao, H, Chandramohan, V, Pegram, C, McLendon, RE, Fredman, P, Månsson, J-E, and Bigner, DD. "GMab-1, a high-affinity anti-3'-isoLM1/3',6'-isoLD1 IgG monoclonal antibody, raised in lacto-series ganglioside-defective knockout mice." Biochem Biophys Res Commun 391.1 (January 1, 2010): 750-755.
PMID
19944071
Source
pubmed
Published In
Biochemical and Biophysical Research Communications
Volume
391
Issue
1
Publish Date
2010
Start Page
750
End Page
755
DOI
10.1016/j.bbrc.2009.11.132

c-Myc represses FOXO3a-mediated transcription of the gene encoding the p27(Kip1) cyclin dependent kinase inhibitor.

The p27(Kip1) (p27) cyclin-dependent kinase inhibitor and c-Myc oncoprotein play essential roles in control of cell cycle progression and apoptosis. Induction of p27 (CDKN1B) gene transcription by Forkhead box O proteins such as FOXO3a leads to growth arrest and apoptosis. Previously, we observed that B cell receptor (surface IgM) engagement of WEHI 231 immature B lymphoma cells with an anti-IgM antibody results in activation of FOXO3a, growth arrest and apoptosis. As ectopic c-Myc expression in these cells prevented anti-IgM induction of p27 and cell death, we hypothesized that c-Myc represses FOXO3a-mediated transcription. Here we show that c-Myc inhibits FOXO3a-mediated activation of the p27 promoter in multiple cell lines. The mechanism of this repression was explored using a combination of co-immunoprecipitation, oligonucleotide precipitation, and chromatin immunoprecipitation experiments. The studies demonstrate a functional association of FOXO3a and c-Myc on a proximal Forkhead binding element in the p27 promoter. This association involves the Myc box II domain of c-Myc and the N-terminal DNA-binding portion of FOXO3a. Analysis of publicly available microarray datasets showed an inverse pattern of c-MYC and p27 RNA expression in primary acute myeloid leukemia, prostate cancer and tongue squamous cell carcinoma samples. The inhibition of FOXO3a-mediated activation of the p27 gene by the high aberrant expression of c-Myc in many tumor cells likely contributes to their uncontrolled proliferation and invasive phenotype.

Authors
Chandramohan, V; Mineva, ND; Burke, B; Jeay, S; Wu, M; Shen, J; Yang, W; Hann, SR; Sonenshein, GE
MLA Citation
Chandramohan, V, Mineva, ND, Burke, B, Jeay, S, Wu, M, Shen, J, Yang, W, Hann, SR, and Sonenshein, GE. "c-Myc represses FOXO3a-mediated transcription of the gene encoding the p27(Kip1) cyclin dependent kinase inhibitor." Journal of cellular biochemistry 104.6 (August 2008): 2091-2106.
PMID
18393360
Source
epmc
Published In
Journal of Cellular Biochemistry
Volume
104
Issue
6
Publish Date
2008
Start Page
2091
End Page
2106
DOI
10.1002/jcb.21765

Reciprocal control of Forkhead box O 3a and c-Myc via the phosphatidylinositol 3-kinase pathway coordinately regulates p27Kip1 levels.

B cell receptor (BCR) engagement of murine WEHI 231 immature B lymphoma cells leads sequentially to a drop in NF-kappa B and c-Myc, and induction of the p27(Kip1) cyclin-dependent kinase inhibitor, which promotes growth arrest and apoptosis. BCR engagement was recently shown to induce a drop in phosphatidylinositol 3-kinase (PI3K)/Akt signaling, preceding the increase in p27. As induction of p27 is due to an increase in gene transcription, we investigated the role of the Forkhead box O (FOXO) transcription factor family, which has been shown to potently induce p27 promoter activity. We demonstrate that pharmacologic inhibitors of PI3K or BCR engagement lead to decreased inactive cytoplasmic levels and increased active functional nuclear FOXO3a. In contrast, inhibition of PI3K/Akt signaling decreased the levels of NF-kappa B and c-Myc, which has been shown to repress p27 promoter activity. To test the effects of ectopic c-Myc on endogenous p27 levels, WEHI 231 cells stably expressing c-Myc or empty vector DNA were prepared. Ectopic c-Myc blocked the induction of p27 expression upon either inhibition of PI3K or BCR engagement. Thus, p27(Kip1) is coordinately regulated via two arms of a signaling pathway that are inversely controlled upon inhibition of PI3K: induction of the activator FOXO3a and down-regulation of the repressor c-Myc.

Authors
Chandramohan, V; Jeay, S; Pianetti, S; Sonenshein, GE
MLA Citation
Chandramohan, V, Jeay, S, Pianetti, S, and Sonenshein, GE. "Reciprocal control of Forkhead box O 3a and c-Myc via the phosphatidylinositol 3-kinase pathway coordinately regulates p27Kip1 levels." Journal of immunology (Baltimore, Md. : 1950) 172.9 (May 2004): 5522-5527.
PMID
15100294
Source
epmc
Published In
Journal of immunology (Baltimore, Md. : 1950)
Volume
172
Issue
9
Publish Date
2004
Start Page
5522
End Page
5527
DOI
10.4049/jimmunol.172.9.5522
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