126
|
Hedegaard CJ, Pegram CN, Bigner DD, Poulsen HS. Abstract 2732: Internalization of the dual-specific immunotoxin D2C7-(scdsFv)-PE38KDEL in malignant glioma cell lines. Cancer Res 2012. [DOI: 10.1158/1538-7445.am2012-2732] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Aim: The aim of this study is firstly to examine if the D2C7-immunotoxin (D2C7-IT) specifically binds to the epidermal growth factor receptor (EGFRwt) and the EGFR-mutant EGFRvIII subsequently inducing cell death. Secondly, to study the internalization of D2C7-IT after binding to EGFRwt/EGFRvIII. Background: Glioblastoma multiforme (GBM) is a malignant primary brain tumor and from diagnose median survival remains around 15 months. Tumor burden can be decreased by operation but eventually the tumor recurs. Thus, novel treatment-strategies for GBM patients are in great demand that would result prolonged median survival and increased quality of life. While EGFRwt and EGFRvIII are not found in normal brain tissue, expression of these are observed in malignant tissue of GBM, and consequently the D2C7-IT has been designed to target both EGFRwt and EGFRvIII. D2C7-IT comprises single chain disulphide stabilized fragment variables (scdsFv) of the bivalent anti-EGFR/EGFRvIII antibody D2C7, a 38 kDa fragment of the pseudomonas exotoxin A (PE38), and finally a C-terminal ‘endoplasmatic reticulum (ER) retention motif’: KDEL. In theory, the D2C7-IT is internalized after binding to EGFR/EGFRvIII and the PE38 moiety is proteolytically cleaved in the endosomal compartment, which releases the C-terminal toxic part of the PE38 into the cytosol. In the cytosol, binding of the KDEL-receptor assures transport to the ER where the toxic moiety inhibits protein synthesis and causes cell death. Methods: Western blotting was applied for examining D2C7-IT-binding to EGFRwt and EGFRvIII in different human malignant cell lines expressing varying levels of EGFRwt or EGFRvIII. MTT assays were used for assessing the impact of D2C7-IT on cell viability in these cell lines. Results: We observed that D2C7-IT binds to cells expressing EGFRwt or EGFRvIII. In addition, the binding on these cells could be inhibited by co-incubating with either EGF or the D2C7 antibody in surplus. Furthermore, D2C7-IT induced a moderate Tyr1173 phosphorylation (marker for internalization) on EGFRwt expressing cells. Concordantly, EGF induced a high level of EGFR-Tyr1173 phosphorylation on EGFRwt expressing cells, which was reduced to a moderate level when co-incubating with D2C7-IT in surplus. D2C7-IT reduced viability in cell cultures expressing EGFR or EGFRvIII while D2C7-IT had no effect on EGFRwt/EGFRvIII negative cells. We are currently trying to visualize the subcellular localizations of D2C7-IT after internalization by fluorescent microscopy. Conclusion: These preliminary results show that D2C7-IT specifically binds to EGFR and EGFRvIII, and reduces viability of EGFRwt/EGFRvIII expressing cells in vitro.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 2732. doi:1538-7445.AM2012-2732
Collapse
|
127
|
Sampson JH, Schmittling RJ, Archer GE, Congdon KL, Nair SK, Reap EA, Desjardins A, Friedman AH, Friedman HS, Herndon JE, Coan A, McLendon RE, Reardon DA, Vredenburgh JJ, Bigner DD, Mitchell DA. A pilot study of IL-2Rα blockade during lymphopenia depletes regulatory T-cells and correlates with enhanced immunity in patients with glioblastoma. PLoS One 2012; 7:e31046. [PMID: 22383993 PMCID: PMC3288003 DOI: 10.1371/journal.pone.0031046] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2011] [Accepted: 12/31/2011] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Preclinical studies in mice have demonstrated that the prophylactic depletion of immunosuppressive regulatory T-cells (T(Regs)) through targeting the high affinity interleukin-2 (IL-2) receptor (IL-2Rα/CD25) can enhance anti-tumor immunotherapy. However, therapeutic approaches are complicated by the inadvertent inhibition of IL-2Rα expressing anti-tumor effector T-cells. OBJECTIVE To determine if changes in the cytokine milieu during lymphopenia may engender differential signaling requirements that would enable unarmed anti-IL-2Rα monoclonal antibody (MAbs) to selectively deplete T(Regs) while permitting vaccine-stimulated immune responses. METHODOLOGY A randomized placebo-controlled pilot study was undertaken to examine the ability of the anti-IL-2Rα MAb daclizumab, given at the time of epidermal growth factor receptor variant III (EGFRvIII) targeted peptide vaccination, to safely and selectively deplete T(Regs) in patients with glioblastoma (GBM) treated with lymphodepleting temozolomide (TMZ). RESULTS AND CONCLUSIONS Daclizumab treatment (n = 3) was well-tolerated with no symptoms of autoimmune toxicity and resulted in a significant reduction in the frequency of circulating CD4+Foxp3+ TRegs in comparison to saline controls (n = 3)( p = 0.0464). A significant (p<0.0001) inverse correlation between the frequency of TRegs and the level of EGFRvIII specific humoral responses suggests the depletion of TRegs may be linked to increased vaccine-stimulated humoral immunity. These data suggest this approach deserves further study. TRIAL REGISTRATION ClinicalTrials.gov NCT00626015.
Collapse
|
128
|
Marshall D, Mitchell DA, Graner MW, Bigner DD. Immunotherapy of brain tumors. HANDBOOK OF CLINICAL NEUROLOGY 2012; 104:309-30. [PMID: 22230450 DOI: 10.1016/b978-0-444-52138-5.00020-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
|
129
|
Sampson JH, Brady M, Raghavan R, Mehta AI, Friedman AH, Reardon DA, Petry NA, Barboriak DP, Wong TZ, Zalutsky MR, Lally-Goss D, Bigner DD. Colocalization of gadolinium-diethylene triamine pentaacetic acid with high-molecular-weight molecules after intracerebral convection-enhanced delivery in humans. Neurosurgery 2011; 69:668-76. [PMID: 21430586 DOI: 10.1227/neu.0b013e3182181ba8] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Convection-enhanced delivery (CED) permits site-specific therapeutic drug delivery within interstitial spaces at increased dosages through circumvention of the blood-brain barrier. CED is currently limited by suboptimal methodologies for monitoring the delivery of therapeutic agents that would permit technical optimization and enhanced therapeutic efficacy. OBJECTIVE To determine whether a readily available small-molecule MRI contrast agent, gadolinium-diethylene triamine pentaacetic acid (Gd-DTPA), could effectively track the distribution of larger therapeutic agents. METHODS Gd-DTPA was coinfused with the larger molecular tracer, I-labeled human serum albumin (I-HSA), during CED of an EGFRvIII-specific immunotoxin as part of treatment for a patient with glioblastoma. RESULTS Infusion of both tracers was safe in this patient. Analysis of both Gd-DTPA and I-HSA during and after infusion revealed a high degree of anatomical and volumetric overlap. CONCLUSION Gd-DTPA may be able to accurately demonstrate the anatomic and volumetric distribution of large molecules used for antitumor therapy with high resolution and in combination with fluid-attenuated inversion recovery (FLAIR) imaging, and provide additional information about leaks into cerebrospinal fluid spaces and resection cavities. Similar studies should be performed in additional patients to validate our findings and help refine the methodologies we used.
Collapse
|
130
|
Zalutsky MR, Boskovitz A, Kuan CT, Pegram CN, Ayriss J, Wikstrand CJ, Buckley AF, Lipp ES, Herndon JE, McLendon RE, Bigner DD. Radioimmunotargeting of malignant glioma by monoclonal antibody D2C7 reactive against both wild-type and variant III mutant epidermal growth factor receptors. Nucl Med Biol 2011; 39:23-34. [PMID: 21958852 DOI: 10.1016/j.nucmedbio.2011.06.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2011] [Revised: 06/17/2011] [Accepted: 06/24/2011] [Indexed: 02/06/2023]
Abstract
INTRODUCTION Malignant glioma remains a significant therapeutic challenge, and immunotherapeutics might be a beneficial approach for these patients. A monoclonal antibody (MAb) specific for multiple molecular targets could expand the treatable patient population and the fraction of tumor cells targeted, with potentially increased efficacy. This motivated the generation of MAb D2C7, which recognizes both wild-type epidermal growth factor receptor (EGFRwt) and a tumor-specific mutant, EGFRvIII. METHODS D2C7 binding affinity was determined by surface plasmon resonance and its specificity characterized through comparison to EGFRwt-specific EGFR.1 and EGFRvIII-specific L8A4 MAbs by flow cytometry and immunohistochemical analysis. The three MAbs were labeled with (125)I or (131)I using Iodogen, and paired-label internalization assays and biodistribution experiments in athymic mice with human tumor xenografts were performed. RESULTS The affinity of D2C7 for EGFRwt and EGFRvIII was 5.2×10(9) M(-1) and 3.6×10(9) M(-1), and cell-surface reactivity with both receptors was documented by flow cytometry. Immunohistochemical analyses revealed D2C7 reactivity with malignant glioma tissue from 90 of 101 patients. Internalization assays performed on EGFRwt-expressing WTT cells and EGFRvIII-expressing NR6M cells indicated a threefold lower degradation of (125)I-labeled D2C7 compared with (131)I-labeled EGFR.1. Uptake of (125)I-labeled D2C7 in NR6M xenografts (52.45±13.97 %ID g(-1) on Day 3) was more than twice that of (131)I-labeled L8A4; a threefold to fivefold tumor delivery advantage was seen when compared to (131)I-labeled EGFR.1 in mice with WTT xenografts. CONCLUSIONS These results suggest that D2C7 warrants further evaluation for the development of MAb-based therapeutics against cancers expressing EGFRwt and EGFRvIII.
Collapse
|
131
|
Reardon DA, Turner S, Peters KB, Desjardins A, Gururangan S, Sampson JH, McLendon RE, Herndon JE, Jones LW, Kirkpatrick JP, Friedman AH, Vredenburgh JJ, Bigner DD, Friedman HS. A review of VEGF/VEGFR-targeted therapeutics for recurrent glioblastoma. J Natl Compr Canc Netw 2011; 9:414-27. [PMID: 21464146 DOI: 10.6004/jnccn.2011.0038] [Citation(s) in RCA: 99] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Glioblastoma, the most common primary malignant brain tumor among adults, is a highly angiogenic and deadly tumor. Angiogenesis in glioblastoma, driven by hypoxia-dependent and independent mechanisms, is primarily mediated by vascular endothelial growth factor (VEGF), and generates blood vessels with distinctive features. The outcome for patients with recurrent glioblastoma is poor because of ineffective therapies. However, recent encouraging rates of radiographic response and progression-free survival, and adequate safety, led the FDA to grant accelerated approval of bevacizumab, a humanized monoclonal antibody against VEGF, for the treatment of recurrent glioblastoma in May 2009. These results have triggered significant interest in additional antiangiogenic agents and therapeutic strategies for patients with both recurrent and newly diagnosed glioblastoma. Given the potent antipermeability effect of VEGF inhibitors, the Radiologic Assessment in Neuro-Oncology (RANO) criteria were recently implemented to better assess response among patients with glioblastoma. Although bevacizumab improves survival and quality of life, eventual tumor progression is the norm. Better understanding of resistance mechanisms to VEGF inhibitors and identification of effective therapy after bevacizumab progression are currently a critical need for patients with glioblastoma.
Collapse
|
132
|
Mehta AI, Persson O, Herndon JE, Archer GE, McLendon R, Heimberger AB, Mitchell DA, Bigner DD, Sampson JH. Reply to M.S. Lesniak. J Clin Oncol 2011. [DOI: 10.1200/jco.2011.35.0256] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
|
133
|
Heaphy CM, de Wilde RF, Jiao Y, Klein AP, Edil BH, Shi C, Bettegowda C, Rodriguez FJ, Eberhart CG, Hebbar S, Offerhaus GJ, McLendon R, Rasheed BA, He Y, Yan H, Bigner DD, Oba-Shinjo SM, Marie SKN, Riggins GJ, Kinzler KW, Vogelstein B, Hruban RH, Maitra A, Papadopoulos N, Meeker AK. Altered telomeres in tumors with ATRX and DAXX mutations. Science 2011; 333:425. [PMID: 21719641 PMCID: PMC3174141 DOI: 10.1126/science.1207313] [Citation(s) in RCA: 793] [Impact Index Per Article: 61.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The proteins encoded by ATRX and DAXX participate in chromatin remodeling at telomeres and other genomic sites. Because inactivating mutations of these genes are common in human pancreatic neuroendocrine tumors (PanNETs), we examined the telomere status of these tumors. We found that 61% of PanNETs displayed abnormal telomeres that are characteristic of a telomerase-independent telomere maintenance mechanism termed ALT (alternative lengthening of telomeres). All of the PanNETs exhibiting these abnormal telomeres had ATRX or DAXX mutations or loss of nuclear ATRX or DAXX protein. ATRX mutations also correlate with abnormal telomeres in tumors of the central nervous system. These data suggest that an alternative telomere maintenance function may operate in human tumors with alterations in the ATRX or DAXX genes.
Collapse
|
134
|
|
135
|
McCarthy BJ, Rankin K, Il'yasova D, Erdal S, Vick N, Ali-Osman F, Bigner DD, Davis F. Assessment of type of allergy and antihistamine use in the development of glioma. Cancer Epidemiol Biomarkers Prev 2011; 20:370-8. [PMID: 21300619 DOI: 10.1158/1055-9965.epi-10-0948] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND Allergies have been associated with decreased risk of glioma; but, associations between duration and timing of allergies, and antihistamine use and glioma risk have been less consistent. The objective was to investigate this association by analyzing types, number, years since diagnosis, and age at diagnosis of allergies, and information on antihistamine usage, including type, duration, and frequency of exposure. METHODS Self-report data on medically diagnosed allergies and antihistamine use were obtained for 419 glioma cases and 612 hospital-based controls from Duke University and NorthShore University HealthSystem. RESULTS High- and low-grade glioma cases were statistically significantly less likely to report any allergy than controls (OR = 0.66, 95% CI: 0.49-0.87 and OR = 0.44, 95% CI: 0.25-0.76, respectively). The number of types of allergies (seasonal, medication, pet, food, and other) was inversely associated with glioma risk in a dose-response manner (P value for trend < 0.05). Age at diagnosis and years since diagnosis of allergies were not associated with glioma risk. Oral antihistamine use was statistically significantly inversely associated with glioma risk, but when stratified by allergy status, remained significant only for those with high-grade glioma and no medically diagnosed allergy. CONCLUSIONS All types of allergies appear to be protective with reduced risk for those with more types of allergies. Antihistamine use, other than in relationship with allergy status, may not influence glioma risk. IMPACT A comprehensive study of allergies and antihistamine use using standardized questions and biological markers will be essential to further delineate the biological mechanism that may be involved in brain tumor development.
Collapse
|
136
|
Vredenburgh JJ, Desjardins A, Reardon DA, Peters KB, Herndon JE, Marcello J, Kirkpatrick JP, Sampson JH, Bailey L, Threatt S, Friedman AH, Bigner DD, Friedman HS. The addition of bevacizumab to standard radiation therapy and temozolomide followed by bevacizumab, temozolomide, and irinotecan for newly diagnosed glioblastoma. Clin Cancer Res 2011; 17:4119-24. [PMID: 21531816 DOI: 10.1158/1078-0432.ccr-11-0120] [Citation(s) in RCA: 122] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
PURPOSE To determine if the addition of bevacizumab to radiation therapy and temozolomide, followed by bevacizumab, temozolomide, and irinotecan, for newly diagnosed glioblastoma patients is safe and effective. EXPERIMENTAL DESIGN A total of 75 patients with newly diagnosed glioblastoma were enrolled in the phase II trial that investigated the addition of bevacizumab to standard radiation therapy and daily temozolomide followed by the addition of bevacizumab and irinotecan to adjuvant temozolomide. The bevacizumab was given at 10 mg/kg every 14 days beginning a minimum of 4 weeks postcraniotomy. Two weeks after radiation therapy, the patients began 6 to 12 cycles of 5-day temozolomide with bevacizumab and irinotecan every 14 days. The primary endpoint was the proportion of patients alive 16 months after informed consent. RESULTS The therapy had moderate toxicity. Three patients, one of whom had a grade 2 central nervous system hemorrhage, came off study during radiation therapy. Seventy patients started the postradiation therapy, and 16 (23%) terminated this adjuvant therapy early because of toxicity. The median overall survival was 21.2 months (95% CI: 17.2-25.4), and 65% of the patients were alive at 16 months (95% CI: 53.4-74.9). The median progression-free survival was 14.2 months (95% CI: 12-16). CONCLUSION The addition of bevacizumab to standard radiation therapy and temozolomide, followed by bevacizumab, irinotecan, and temozolomide, for the treatment of newly diagnosed glioblastoma has moderate toxicity and may improve efficacy compared with historical controls. The results from phase III trials are required before the role of bevacizumab for newly diagnosed glioblastoma is established.
Collapse
|
137
|
Yan H, Reitman ZJ, Jin G, Spasojevic I, He Y, Bigner DD, Karoly ED, Yang J, Kinzler KW, Vogelstein B. Abstract LB-257: Profiling the effects of IDH1 and IDH2 mutants on the glioma cell metabolome. Cancer Res 2011. [DOI: 10.1158/1538-7445.am2011-lb-257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Somatic hotspot mutations in the NADP+-dependent isocitrate dehydrogenases, IDH1 and IDH2, arise frequently in gliomas. These gliomas include WHO grades II and III oligodendrogliomas and astrocytomas, as well as WHO grade IV secondary glioblastomas. When mutated, IDH1 and IDH2 gain the ability to produce (R)-2-hydroxyglutarate (2HG) and may dominant-negatively inhibit IDH1-WT. Aside from these specific functions, the downstream effect of these metabolic enzyme mutations on cellular metabolism is unknown. To identify metabolic alterations caused by IDH1 and IDH2 mutants, we used three mass spectrometry methods (GC-MS/MS, LC-MS/MS +ESI, and LC-MS/MS -ESI) to profile >200 biochemicals in lysates of human oligodendroglial cell line (HOG) cells that homologously express IDH1-R132H or IDH2-R172K, which are the most frequent IDH1 and IDH2 mutants in glioma, respectively. To determine whether 2HG production or inhibition of IDH1-WT could mediate similar effects on cellular metabolism as IDH mutant expression, we also analyzed cells treated cells with either 7.5mM or 30mM 2HG as well as cells with stable shRNA knockdown of endogenous IDH1-WT. Unsupervised hierarchical clustering, univariate threshold tests, correlation analysis, and principal component analysis revealed that cells expressing IDH1-R132H and IDH2-R172K have similar metabolite profiles, and that 2HG treatment also results in a similar profile. However, cell with shRNA IDH1 knockdown shared few metabolic features with cells expressing IDH mutants. Metabolite set enrichment analyses revealed that numerous amino acids, N-acetylated amino acids, TCA cycle metabolites, glutathione metabolites, and choline derivatives were markedly altered in IDH-mutant expressing cells. Strikingly, we found that N-acetyl-aspartyl-glutamate (NAAG), a common brain metabolite, is 50-fold reduced in cells expressing IDH1-R132H and >2-fold reduced in human glioma tissues with IDH1-R132H compared to glioma tissues without IDH mutations. This work shows that IDH mutants can induce widespread cellular metabolic changes. Additionally, the metabolites that were found to be altered in this study may play a role in glioma pathogenesis and may be useful for diagnosis or treatment for gliomas.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr LB-257. doi:10.1158/1538-7445.AM2011-LB-257
Collapse
|
138
|
Davis F, Il'yasova D, Rankin K, McCarthy B, Bigner DD. Medical diagnostic radiation exposures and risk of gliomas. Radiat Res 2011; 175:790-6. [PMID: 21466382 DOI: 10.1667/rr2186.1] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
High-dose ionizing radiation is an established risk factor for glioma, but it remains unknown whether moderate- and low-dose radiation increase glioma risk. In this analysis, we assessed the evidence that self-reported exposures to diagnostic ionizing radiation, including computerized tomography (CT) scans, is associated with increased risk of adult glioma. While no independent association was observed for CT scans alone (3+ scans compared to none P = 0.08 and 1-2 scans compared to none P = 0.68), our findings suggest an increased risk of adult gliomas with cumulative exposure to three or more CT scans to the head and neck region (OR = 1.97, 95% CI: 0.92-4.23) limited to those who reported a family history of cancer: the P value for the interaction between having three or more CT scans and family history of cancer was 0.08. The stratum-specific adjusted OR for those with family history of cancer was more than three times that for the sub-group without family history of cancer. While there is some potential for symptom-related bias, one might expect this to be present for all diagnostic procedures rather than specific to one procedure. The interaction between CT scans and glioma with family history of cancer supports the biological plausibility of our findings, because similar results have been found for breast cancer and radiation. This observational data will increase awareness about potential risks associated with CT scans and the need to minimize the use of unnecessary examinations.
Collapse
|
139
|
Choi BD, Cai M, Bigner DD, Mehta AI, Kuan CT, Sampson JH. Bispecific antibodies engage T cells for antitumor immunotherapy. Expert Opin Biol Ther 2011; 11:843-53. [PMID: 21449821 DOI: 10.1517/14712598.2011.572874] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
INTRODUCTION Although considerable evidence supports the hypothesis that T cells play a critical role in the immune response against cancer, the ability to mount and sustain tumor-specific cellular responses in vivo remains a challenge. A strategy that harnesses the cytotoxic advantage of T cell therapy is the use of bispecific antibodies designed to engage and activate endogenous polyclonal T cell populations via the CD3 complex, but only in the presence of a tumor antigen. While antibody constructs with dual specificity were first described as anticancer therapeutics over 25 years ago, it was not until recently that one subclass of bispecific single-chain antibody, the bispecific T cell engager (BiTE), emerged as superior to previous iterations in achieving efficacy in animal models and early clinical trials. AREAS COVERED The evolution of bispecific antibodies in antitumor immunotherapy is reviewed and the greatest hurdles impeding their clinical translation are discussed, specifically in the context of immunoprivileged sites as is the case for intracerebral malignancy. EXPERT OPINION The BiTE platform has great potential in the treatment of malignant disease. Despite burgeoning interest in bispecific antibodies and permutations thereof, the issues of stability and cost-effective production persist as obstacles.
Collapse
|
140
|
Mehta AI, Kanaly CW, Friedman AH, Bigner DD, Sampson JH. Monitoring radiographic brain tumor progression. Toxins (Basel) 2011; 3:191-200. [PMID: 22069705 PMCID: PMC3202817 DOI: 10.3390/toxins3030191] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2011] [Revised: 02/03/2011] [Accepted: 03/11/2011] [Indexed: 01/28/2023] Open
Abstract
Determining radiographic progression in primary malignant brain tumors has posed a significant challenge to the neuroncology community. Glioblastoma multiforme (GBM, WHO Grade IV) through its inherent heterogeneous enhancement, growth patterns, and irregular nature has been difficult to assess for progression. Our ability to detect tumor progression radiographically remains inadequate. Despite the advanced imaging techniques, detecting tumor progression continues to be a clinical challenge. Here we review the different criteria used to detect tumor progression, and highlight the inherent challenges with detection of progression.
Collapse
|
141
|
Hens M, Vaidyanathan G, Zhao XG, Bigner DD, Zalutsky MR. Anti-EGFRvIII monoclonal antibody armed with 177Lu: in vivo comparison of macrocyclic and acyclic ligands. Nucl Med Biol 2011; 37:741-50. [PMID: 20870149 DOI: 10.1016/j.nucmedbio.2010.04.020] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2009] [Revised: 03/23/2010] [Accepted: 04/04/2010] [Indexed: 10/19/2022]
Abstract
INTRODUCTION Monoclonal antibody (mAb) L8A4 binds specifically to the epidermal growth factor receptor variant III (EGFRvIII) that is present on gliomas but not on normal tissues, and is internalized rapidly after receptor binding. Because of the short range of its β-emissions, labeling this mAb with (177)Lu would be an attractive approach for the treatment of residual tumor margins remaining after surgical debulking of brain tumors. MATERIALS AND METHODS L8A4 mAb was labeled with (177)Lu using the acyclic ligands [(R)-2-amino-3-(4-isothiocyanatophenyl)propyl]-trans-(S,S)-cyclohexane-1,2-diamine-pentaacetic acid (CHX-A″-DTPA) and 2-(4-isothiocyanatobenzyl)-6-methyldiethylene-triaminepentaacetic acid (1B4M-DTPA), and the macrocyclic ligands S-2-(4-isothiocyanatobenzyl)-1,4,7,10-tetraazacyclododecane-tetraacetic acid (C-DOTA) and α-(5-isothiocyanato-2-methoxyphenyl)-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (MeO-DOTA). Paired-label tissue distribution experiments were performed in athymic mice bearing subcutaneous EGFRvIII-expressing U87.ΔEGFR glioma xenografts over a period of 1 to 8 days to directly compare (177)Lu-labeled L8A4 to L8A4 labeled with (125)I using N-succinimidyl 4-guanidinomethyl-3-[(125)I]iodobenzoate ([(125)I]SGMIB). RESULTS Except with C-DOTA, tumor uptake for the (177)Lu-labeled mAb was significantly higher than the co-administered radioiodinated preparation; however, this was also the case for spleen, liver, bone and kidneys. Tumor/normal tissue ratios for (177)Lu-1B4M-DTPA-L8A4 and, to an even greater extent, (177)Lu-MeO-DOTA-L8A4 were higher than those for [(125)I]SGMIB-L8A4 in most other tissues. CONCLUSIONS Tumor and normal tissue distribution patterns for this anti-EGFRvIII mAb were dependent on the nature of the bifunctional chelate used for (177)Lu labeling. Optimal results were obtained with 1B4M-DTPA and MeO-DOTA, suggesting no clear advantage for acyclic vs. macrocyclic ligands for this application.
Collapse
|
142
|
Kato Y, Vaidyanathan G, Kaneko MK, Mishima K, Srivastava N, Chandramohan V, Pegram C, Keir ST, Kuan CT, Bigner DD, Zalutsky MR. Evaluation of anti-podoplanin rat monoclonal antibody NZ-1 for targeting malignant gliomas. Nucl Med Biol 2011; 37:785-94. [PMID: 20870153 DOI: 10.1016/j.nucmedbio.2010.03.010] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2009] [Revised: 03/04/2010] [Accepted: 03/25/2010] [Indexed: 10/19/2022]
Abstract
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.
Collapse
|
143
|
Jin G, Reitman ZJ, Spasojevic I, Batinic-Haberle I, Yang J, Schmidt-Kittler O, Bigner DD, Yan H. 2-hydroxyglutarate production, but not dominant negative function, is conferred by glioma-derived NADP-dependent isocitrate dehydrogenase mutations. PLoS One 2011; 6:e16812. [PMID: 21326614 PMCID: PMC3033901 DOI: 10.1371/journal.pone.0016812] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2010] [Accepted: 01/03/2011] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Gliomas frequently contain mutations in the cytoplasmic NADP(+)-dependent isocitrate dehydrogenase (IDH1) or the mitochondrial NADP(+)-dependent isocitrate dehydrogenase (IDH2). Several different amino acid substitutions recur at either IDH1 R132 or IDH2 R172 in glioma patients. Genetic evidence indicates that these mutations share a common gain of function, but it is unclear whether the shared function is dominant negative activity, neomorphic production of (R)-2-hydroxyglutarate (2HG), or both. METHODOLOGY/PRINCIPAL FINDINGS We show by coprecipitation that five cancer-derived IDH1 R132 mutants bind IDH1-WT but that three cancer-derived IDH2 R172 mutants exert minimal binding to IDH2-WT. None of the mutants dominant-negatively lower isocitrate dehydrogenase activity at physiological (40 µM) isocitrate concentrations in mammalian cell lysates. In contrast to this, all of these mutants confer 10- to 100-fold higher 2HG production to cells, and glioma tissues containing IDH1 R132 or IDH2 R172 mutations contain high levels of 2HG compared to glioma tissues without IDH mutations (54.4 vs. 0.1 mg 2HG/g protein). CONCLUSIONS Binding to, or dominant inhibition of, WT IDH1 or IDH2 is not a shared feature of the IDH1 and IDH2 mutations, and thus is not likely to be important in cancer. The fact that the gain of the enzymatic activity to produce 2HG is a shared feature of the IDH1 and IDH2 mutations suggests that this is an important function for these mutants in driving cancer pathogenesis.
Collapse
|
144
|
Keir ST, Dewhirst MW, Kirkpatrick JP, Bigner DD, Batinic-Haberle I. Cellular redox modulator, ortho Mn(III) meso-tetrakis(N-n-hexylpyridinium-2-yl)porphyrin, MnTnHex-2-PyP(5+) in the treatment of brain tumors. Anticancer Agents Med Chem 2011; 11:202-12. [PMID: 21291403 PMCID: PMC3357315 DOI: 10.2174/187152011795255957] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2010] [Accepted: 02/04/2011] [Indexed: 01/11/2023]
Abstract
Despite intensive efforts to improve multimodal treatment of brain tumor, survival remains limited. Current therapy consists of a combination of surgery, irradiation and chemotherapy with predisposition to long-term complications. Identifying novel targeted therapies is therefore at the forefront of brain tumor research. This study explores the utility of a manganese porphyrin in a brain tumor model. The compound used is ortho isomer, mangnese(III) meso-tetrakis(N-n-hexylpyridinium-2-yl)porphyrin, MnTnHex-2-PyP(5+). It is a powerful SOD mimic and peroxynitrite scavenger and a potent modulator of redox-based cellular transcriptional activity, able to suppress excessive immune and inflammatory responses and in turn proliferative pathways. It is further one of the most lipophilic compound among cationic Mn(III) N-alkylpyridylporphyrins, and thus accumulates predominantly in mitochondria relative to cytosol. In mitochondria, MnTnHex-2-PyP(5+) mimics our key antioxidant system, mitochondrial superoxide dismutase, MnSOD, whose overexpression has been widely shown to suppress tumor growth. Importantly, MnTnHex-2-PyP(5+) crosses blood brain barrier in sufficient amounts to demonstrate efficacy in treating CNS injuries. For those reasons we elected to test its effects in inhibiting brain tumor growth. This study is the first report of the antitumor properties of MnTnHex-2-PyP(5+) as a single agent in adult and pediatric glioblastoma multiforme (D-54 MG, D-245 MG, D-256 MG, D-456 MG) and pediatric medulloblastoma (D-341 MED), and is the first case where a redox-able metal complex has been used in glioma therapy. When given subcutaneously to mice bearing subcutaneous and intracranial xenografts, MnTnHex-2-PyP(5+) caused a significant (P ≤ 0.001) growth delay in D 245 MG, D-256 MG, D-341 MED, and D-456 MG tumors. Growth delay for mice bearing subcutaneous xenografts ranged from 3 days in D-54 MG to 34 days in D-341 MED. With mice bearing intracranial xenografts, MnTnHex-2-PyP(5+) increases median survival by 33% in adult glioblastoma multiforme (D-256 MG; p≤ 0.001) and 173% in pediatric medulloblastoma (D-341 MED, <0.001). The beneficial effects of MnTnHex-2-PyP(5+) are presumably achieved either (1) indirectly via elimination of signaling reactive oxygen and nitrogen species (in particular superoxide and peroxynitrite) which in turn would prevent activation of transcription factors; or (2) directly by coupling with cellular reductants and redox-sensitive signaling proteins. The former action is antioxidative while the latter action is presumably pro-oxidative in nature. Our findings suggest that the use of Mn porphyrin-based SOD mimics, and in particular lipophilic analogues such as MnTnHex-2-PyP(5+), is a promising approach for brain tumor therapy.
Collapse
|
145
|
Parsons DW, Li M, Zhang X, Jones S, Leary RJ, Lin JCH, Boca SM, Carter H, Samayoa J, Bettegowda C, Gallia GL, Jallo GI, Binder ZA, Nikolsky Y, Hartigan J, Smith DR, Gerhard DS, Fults DW, VandenBerg S, Berger MS, Marie SKN, Shinjo SMO, Clara C, Phillips PC, Minturn JE, Biegel JA, Judkins AR, Resnick AC, Storm PB, Curran T, He Y, Rasheed BA, Friedman HS, Keir ST, McLendon R, Northcott PA, Taylor MD, Burger PC, Riggins GJ, Karchin R, Parmigiani G, Bigner DD, Yan H, Papadopoulos N, Vogelstein B, Kinzler KW, Velculescu VE. The genetic landscape of the childhood cancer medulloblastoma. Science 2011; 331:435-9. [PMID: 21163964 PMCID: PMC3110744 DOI: 10.1126/science.1198056] [Citation(s) in RCA: 558] [Impact Index Per Article: 42.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Medulloblastoma (MB) is the most common malignant brain tumor of children. To identify the genetic alterations in this tumor type, we searched for copy number alterations using high-density microarrays and sequenced all known protein-coding genes and microRNA genes using Sanger sequencing in a set of 22 MBs. We found that, on average, each tumor had 11 gene alterations, fewer by a factor of 5 to 10 than in the adult solid tumors that have been sequenced to date. In addition to alterations in the Hedgehog and Wnt pathways, our analysis led to the discovery of genes not previously known to be altered in MBs. Most notably, inactivating mutations of the histone-lysine N-methyltransferase genes MLL2 or MLL3 were identified in 16% of MB patients. These results demonstrate key differences between the genetic landscapes of adult and childhood cancers, highlight dysregulation of developmental pathways as an important mechanism underlying MBs, and identify a role for a specific type of histone methylation in human tumorigenesis.
Collapse
|
146
|
Sampson JH, Aldape KD, Archer GE, Coan A, Desjardins A, Friedman AH, Friedman HS, Gilbert MR, Herndon JE, McLendon RE, Mitchell DA, Reardon DA, Sawaya R, Schmittling R, Shi W, Vredenburgh JJ, Bigner DD, Heimberger AB. Greater chemotherapy-induced lymphopenia enhances tumor-specific immune responses that eliminate EGFRvIII-expressing tumor cells in patients with glioblastoma. Neuro Oncol 2010; 13:324-33. [PMID: 21149254 DOI: 10.1093/neuonc/noq157] [Citation(s) in RCA: 261] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Epidermal growth factor receptor variant III (EGFRvIII) is a tumor-specific mutation widely expressed in glioblastoma multiforme (GBM) and other neoplasms, but absent from normal tissues. Immunotherapeutic targeting of EGFRvIII could eliminate neoplastic cells more precisely but may be inhibited by concurrent myelosuppressive chemotherapy like temozolomide (TMZ), which produces a survival benefit in GBM. A phase II, multicenter trial was undertaken to assess the immunogenicity of an experimental EGFRvIII-targeted peptide vaccine in patients with GBM undergoing treatment with serial cycles of standard-dose (STD) (200 mg/m(2) per 5 days) or dose-intensified (DI) TMZ (100 mg/m(2) per 21 days). All patients receiving STD TMZ exhibited at least a transient grade 2 lymphopenia, whereas those receiving DI TMZ exhibited a sustained grade 3 lymphopenia (<500 cells/μL). CD3(+) T-cell (P = .005) and B-cell (P = .004) counts were reduced significantly only in the DI cohort. Patients in the DI cohort had an increase in the proportion of immunosuppressive regulatory T cells (T(Reg); P = .008). EGFRvIII-specific immune responses developed in all patients treated with either regimen, but the DI TMZ regimen produced humoral (P = .037) and delayed-type hypersensitivity responses (P = .036) of greater magnitude. EGFRvIII-expressing tumor cells were also eradicated in nearly all patients (91.6%; CI(95): 64.0%-99.8%; P < .0001). The median progression-free survival (15.2 months; CI(95): 11.0-18.5 months; hazard ratio [HR] = 0.35; P = .024) and overall survival (23.6 months; CI(95): 18.5-33.1 months; HR = 0.23; P = .019) exceeded those of historical controls matched for entry criteria and adjusted for known prognostic factors. EGFRvIII-targeted vaccination induces patient immune responses despite therapeutic TMZ-induced lymphopenia and eliminates EGFRvIII-expressing tumor cells without autoimmunity.
Collapse
|
147
|
Kuan CT, Chang J, Mansson JE, Li J, Pegram C, Fredman P, McLendon RE, Bigner DD. Multiple phenotypic changes in mice after knockout of the B3gnt5 gene, encoding Lc3 synthase--a key enzyme in lacto-neolacto ganglioside synthesis. BMC DEVELOPMENTAL BIOLOGY 2010; 10:114. [PMID: 21087515 PMCID: PMC2998480 DOI: 10.1186/1471-213x-10-114] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/08/2009] [Accepted: 11/18/2010] [Indexed: 01/21/2023]
Abstract
BACKGROUND Ganglioside biosynthesis occurs through a multi-enzymatic pathway which at the lactosylceramide step is branched into several biosynthetic series. Lc3 synthase utilizes a variety of galactose-terminated glycolipids as acceptors by establishing a glycosidic bond in the beta-1,3-linkage to GlcNaAc to extend the lacto- and neolacto-series gangliosides. In order to examine the lacto-series ganglioside functions in mice, we used gene knockout technology to generate Lc3 synthase gene B3gnt5-deficient mice by two different strategies and compared the phenotypes of the two null mouse groups with each other and with their wild-type counterparts. RESULTS B3gnt5 gene knockout mutant mice appeared normal in the embryonic stage and, if they survived delivery, remained normal during early life. However, about 9% developed early-stage growth retardation, 11% died postnatally in less than 2 months, and adults tended to die in 5-15 months, demonstrating splenomegaly and notably enlarged lymph nodes. Without lacto-neolacto series gangliosides, both homozygous and heterozygous mice gradually displayed fur loss or obesity, and breeding mice demonstrated reproductive defects. Furthermore, B3gnt5 gene knockout disrupted the functional integrity of B cells, as manifested by a decrease in B-cell numbers in the spleen, germinal center disappearance, and less efficiency to proliferate in hybridoma fusion. CONCLUSIONS These novel results demonstrate unequivocally that lacto-neolacto series gangliosides are essential to multiple physiological functions, especially the control of reproductive output, and spleen B-cell abnormality. We also report the generation of anti-IgG response against the lacto-series gangliosides 3'-isoLM1 and 3',6'-isoLD1.
Collapse
|
148
|
Kuan CT, Wakiya K, Keir ST, Li J, Herndon JE, Pastan I, Bigner DD. Affinity-matured anti-glycoprotein NMB recombinant immunotoxins targeting malignant gliomas and melanomas. Int J Cancer 2010; 129:111-21. [PMID: 20824708 DOI: 10.1002/ijc.25645] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2010] [Accepted: 08/18/2010] [Indexed: 11/08/2022]
Abstract
Glycoprotein NMB (GPNMB), a transmembrane glycoprotein highly expressed in high-grade gliomas (HGGs), is an attractive target in cancer immunotherapy. We isolated a GPNMB-specific scFv clone, G49, from a human synthetic phage-display library. To obtain mutant single-chain variable-fragment antibodies (scFvs) with improved affinity and immunotoxins with increased activity, we subjected G49 to in vitro affinity maturation by a complementarity-determining-region (CDR) random-mutagenesis technique. Using light-chain CDR3 mutagenesis, cell-based panning by phage display, subsequent heavy-chain CDR1 mutagenesis, and flow-cytometric selection by yeast-surface display, we generated the mutant scFv clone 902V, with an overall 11-fold increase in affinity for GPNMB. Clone 902V was further randomized throughout the whole scFv by error-prone PCR, and one mutant, F6V, was selected by yeast-surface display. F6V scFv, differing from 902V by one amino-acid change in the light-chain CDR2, exhibited an affinity for GPNMB of 0.30 nM. The F6V mutant scFv clone was fused with a truncated form of Pseudomonas exotoxin A to form the immunotoxin F6V-PE38. F6V-PE38 demonstrated significant protein-synthesis-inhibition activity on GPNMB-expressing glioma and malignant melanoma cells (IC(50) = 0.5 ng/ml [8 pM]), a 60-fold improvement over G49 activity, but no cytotoxicity on GPNMB-negative cells. Furthermore, F6V-PE38 exhibited significant antitumor activity against subcutaneous malignant glioma xenografts in two nude-mouse models and a melanoma neoplastic meningitis model in athymic rats. These GPNMB-specific scFv antibodies and immunotoxins hold promise as reagents in targeted therapy for HGGs and other GPNMB-expressing malignancies.
Collapse
|
149
|
Sampson JH, Heimberger AB, Archer GE, Aldape KD, Friedman AH, Friedman HS, Gilbert MR, Herndon JE, McLendon RE, Mitchell DA, Reardon DA, Sawaya R, Schmittling RJ, Shi W, Vredenburgh JJ, Bigner DD. Immunologic escape after prolonged progression-free survival with epidermal growth factor receptor variant III peptide vaccination in patients with newly diagnosed glioblastoma. J Clin Oncol 2010; 28:4722-9. [PMID: 20921459 DOI: 10.1200/jco.2010.28.6963] [Citation(s) in RCA: 586] [Impact Index Per Article: 41.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
PURPOSE Immunologic targeting of tumor-specific gene mutations may allow precise eradication of neoplastic cells without toxicity. Epidermal growth factor receptor variant III (EGFRvIII) is a constitutively activated and immunogenic mutation not expressed in normal tissues but widely expressed in glioblastoma multiforme (GBM) and other neoplasms. PATIENTS AND METHODS A phase II, multicenter trial was undertaken to assess the immunogenicity of an EGFRvIII-targeted peptide vaccine and to estimate the progression-free survival (PFS) and overall survival (OS) of vaccinated patients with newly diagnosed EGFRvIII-expressing GBM with minimal residual disease. Intradermal vaccinations were given until toxicity or tumor progression was observed. Sample size was calculated to differentiate between PFS rates of 20% and 40% 6 months after vaccination. RESULTS There were no symptomatic autoimmune reactions. The 6-month PFS rate after vaccination was 67% (95% CI, 40% to 83%) and after diagnosis was 94% (95% CI, 67% to 99%; n = 18). The median OS was 26.0 months (95% CI, 21.0 to 47.7 months). After adjustment for age and Karnofsky performance status, the OS of vaccinated patients was greater than that observed in a control group matched for eligibility criteria, prognostic factors, and temozolomide treatment (hazard ratio, 5.3; P = .0013; n = 17). The development of specific antibody (P = .025) or delayed-type hypersensitivity (P = .03) responses to EGFRvIII had a significant effect on OS. At recurrence, 82% (95% CI, 48% to 97%) of patients had lost EGFRvIII expression (P < .001). CONCLUSION EGFRvIII-targeted vaccination in patients with GBM warrants investigation in a phase III, randomized trial.
Collapse
|
150
|
Kuan CT, Wakiya K, Herndon JE, Lipp ES, Pegram CN, Riggins GJ, Rasheed A, Szafranski SE, McLendon RE, Wikstrand CJ, Bigner DD. MRP3: a molecular target for human glioblastoma multiforme immunotherapy. BMC Cancer 2010; 10:468. [PMID: 20809959 PMCID: PMC2940806 DOI: 10.1186/1471-2407-10-468] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2010] [Accepted: 09/01/2010] [Indexed: 02/05/2023] Open
Abstract
Background Glioblastoma multiforme (GBM) is refractory to conventional therapies. To overcome the problem of heterogeneity, more brain tumor markers are required for prognosis and targeted therapy. We have identified and validated a promising molecular therapeutic target that is expressed by GBM: human multidrug-resistance protein 3 (MRP3). Methods We investigated MRP3 by genetic and immunohistochemical (IHC) analysis of human gliomas to determine the incidence, distribution, and localization of MRP3 antigens in GBM and their potential correlation with survival. To determine MRP3 mRNA transcript and protein expression levels, we performed quantitative RT-PCR, raising MRP3-specific antibodies, and IHC analysis with biopsies of newly diagnosed GBM patients. We used univariate and multivariate analyses to assess the correlation of RNA expression and IHC of MRP3 with patient survival, with and without adjustment for age, extent of resection, and KPS. Results Real-time PCR results from 67 GBM biopsies indicated that 59/67 (88%) samples highly expressed MRP3 mRNA transcripts, in contrast with minimal expression in normal brain samples. Rabbit polyvalent and murine monoclonal antibodies generated against an extracellular span of MRP3 protein demonstrated reactivity with defined MRP3-expressing cell lines and GBM patient biopsies by Western blotting and FACS analyses, the latter establishing cell surface MRP3 protein expression. IHC evaluation of 46 GBM biopsy samples with anti-MRP3 IgG revealed MRP3 in a primarily membranous and cytoplasmic pattern in 42 (91%) of the 46 samples. Relative RNA expression was a strong predictor of survival for newly diagnosed GBM patients. Hazard of death for GBM patients with high levels of MRP3 RNA expression was 2.71 (95% CI: 1.54-4.80) times that of patients with low/moderate levels (p = 0.002). Conclusions Human GBMs overexpress MRP3 at both mRNA and protein levels, and elevated MRP3 mRNA levels in GBM biopsy samples correlated with a higher risk of death. These data suggest that the tumor-associated antigen MRP3 has potential use for prognosis and as a target for malignant glioma immunotherapy.
Collapse
|