Anthony Miliotto

Epigenetic Potentiation of NY-ESO-1 Vaccine Therapy in Human Ovarian Cancer

Odunsi and colleagues show that the DNA methyltransferase inhibitor decitabine augmented the efficacy of the NY-ESO-1 vaccine and doxorubicin treatment of patients with refractory epithelial ovarian cancer, demonstrating the potential of the combined chemo-immunotherapy regimen. The cancer–testis/cancer germline antigen, NY-ESO-1, is a vaccine target in epithelial ovarian cancer (EOC), but its limited expression is a barrier to vaccine efficacy. As NY-ESO-1 is regulated by DNA methylation, we hypothesized that DNA methyltransferase inhibitors may augment NY-ESO-1 vaccine therapy. In agreement, global DNA hypomethylation in EOC was associated with the presence of circulating antibodies to NY-ESO-1. Preclinical studies using EOC cell lines showed that decitabine treatment enhanced both NY-ESO-1 expression and NY-ESO-1–specific CTL-mediated responses. On the basis of these observations, we performed a phase I dose-escalation trial of decitabine, as an addition to NY-ESO-1 vaccine and doxorubicin liposome chemotherapy, in 12 patients with relapsed EOC. The regimen was safe, with limited and clinically manageable toxicities. Both global and promoter-specific DNA hypomethylation occurred in blood and circulating DNAs, the latter of which may reflect tumor cell responses. Increased NY-ESO-1 serum antibodies and T-cell responses were observed in the majority of patients, and antibody spreading to additional tumor antigens was also observed. Finally, disease stabilization or partial clinical response occurred in six of ten evaluable patients. On the basis of these encouraging results, evaluation of similar combinatorial chemo-immunotherapy regimens in EOC and other tumor types is warranted. Cancer Immunol Res; 2(1); 37–49. ©2014 AACR.

NY-ESO-1 Cancer Testis Antigen Demonstrates High Immunogenicity in Triple Negative Breast Cancer

Purpose NY-ESO-1 cancer testis (CT) antigen is an attractive candidate for immunotherapy as a result of its high immunogenicity. The aim of this study was to explore the potential for NY-ESO-1 antigen directed immunotherapy in triple negative breast cancer (TNBC) by determining the frequency of expression by immunohistochemistry (IHC) and the degree of inherent immunogenicity to NY-ESO-1. Experimental Design 168 TNBC and 47 ER+/HER2- primary breast cancer specimens were used to determine NY-ESO-1 frequency by IHC. As previous studies have shown that patients with a robust innate humoral immune response to CT antigens are more likely to develop CD8 T-cell responses to NY-ESO-1 peptides, we evaluated the degree to which patients with NY-ESO-1 expression had inherent immunogenicity by measuring antibodies. The relationship between NY-ESO-1 expression and CD8+ T lymphocytes was also examined. Results The frequency of NY-ESO-1 expression in the TNBC cohort was 16% versus 2% in ER+/HER2- patients. A higher NY-ESO-1 score was associated with a younger age at diagnosis in the TNBC patients with NY-ESO-1 expression (p = 0.026). No differences in OS (p = 0.278) or PFS (p = 0.238) by NY-ESO-1 expression status were detected. Antibody responses to NY-ESO-1 were found in 73% of TNBC patients whose tumors were NY-ESO-1 positive. NY-ESO-1 positive patients had higher CD8 counts than negative patients (p = 0.018). Conclusion NY-ESO-1 is expressed in a substantial subset of TNBC patients and leads to a high humoral immune response in a large proportion of these individuals. Given these observations, patients with TNBC may benefit from targeted therapies directed against NY-ESO-1.

Expression and immune responses to MAGE antigens predict survival in epithelial ovarian cancer.

The MAGE cancer-testis antigens (CTA) are attractive candidates for immunotherapy. The aim of this study was to determine the frequency of expression, humoral immunity and prognostic significance of MAGE CTA in human epithelial ovarian cancer (EOC). mRNA or protein expression frequencies were determined for MAGE-A1, -A3, -A4, -A10 and -C1 (CT7) in tissue samples obtained from 400 patients with EOC. The presence of autologous antibodies against the MAGE antigens was determined from 285 serum samples. The relationships between MAGE expression, humoral immunity to MAGE antigens, and clinico-pathologic characteristics were studied. The individual frequencies of expression were as follows: A1: 15% (42/281), A3: 36% (131/390), A4: 47% (186/399), A10: 52% (204/395), C1: 16% (42/267). Strong concordant expression was noted with MAGE-A1:–A4, MAGE-A1:–C1 and MAGE-A4:–A10 (p<0.0005). Expression of MAGE-A1 or -A10 antigens resulted in poor progression free survival (PFS) (OR 1.44, CI 1.01–2.04, p = 0.044 and OR 1.3, CI 1.03–1.64, p = 0.03, respectively); whereas, MAGE-C1 expression was associated with improved PFS (OR 0.62, CI 0.42–0.92, p = 0.016). The improved PFS observed for MAGE-C1 expression, was diminished by co-expression of MAGE-A1 or -A10. Spontaneous humoral immunity to the MAGE antigens was present in 9% (27/285) of patients, and this predicted poor overall survival (log-rank test p = 0.0137). These findings indicate that MAGE-A1, MAGE-A4, MAGE-A3, and MAGE-A10 are priority attractive targets for polyvalent immunotherapy in ovarian cancer patients.

Compensatory upregulation of PD-1, LAG-3, and CTLA-4 limits the efficacy of single-agent checkpoint blockade in metastatic ovarian cancer

ABSTRACT Tumor-associated or -infiltrating lymphocytes (TALs or TILs) co-express multiple immune inhibitory receptors that contribute to immune suppression in the ovarian tumor microenvironment (TME). Dual blockade of PD-1 along with LAG-3 or CTLA-4 has been shown to synergistically enhance T-cell effector function, resulting in a delay in murine ovarian tumor growth. However, the mechanisms underlying this synergy and the relative contribution of other inhibitory receptors to immune suppression in the ovarian TME are unknown. Here, we report that multiple immune checkpoints are expressed in TALs and TILs isolated from ovarian tumor-bearing mice. Importantly, blockade of PD-1, LAG-3, or CTLA-4 alone using genetic ablation or blocking antibodies conferred a compensatory upregulation of the other checkpoint pathways, potentiating their capacity for local T-cell suppression that, in turn, could be overcome through combinatorial blockade strategies. Whereas single-agent blockade led to tumor outgrowth in all animals, dual antibody blockade against PD-1/CTLA-4 or triple blockade against PD-1/LAG-3/CTLA-4 resulted in tumor-free survival in 20% of treated mice. In contrast, dual blockade of LAG-3 and CTLA-4 pathways using PD-1 knockout mice led to tumor-free survival in 40% of treated mice, suggesting a hierarchical ordering of checkpoint function. Durable antitumor immunity was most strongly associated with increased numbers of CD8+ T cells, the frequency of cytokine-producing effector T cells, reduced frequency of Tregs and arginine-expressing monocytic myeloid-derived suppressor cells in the peritoneal TME. These data provide a basis for combinatorial checkpoint blockade in clinical intervention for ovarian cancer.

Split T Cell Tolerance against a Self/Tumor Antigen: Spontaneous CD4+ but Not CD8+ T Cell Responses against p53 in Cancer Patients and Healthy Donors

Analyses of NY-ESO-1-specific spontaneous immune responses in cancer patients revealed that antibody and both CD4+ and CD8+ T cell responses were induced together in cancer patients. To explore whether such integrated immune responses are also spontaneously induced for other tumor antigens, we have evaluated antibody and T cell responses against self/tumor antigen p53 in ovarian cancer patients and healthy individuals. We found that 21% (64/298) of ovarian cancer patients but no healthy donors showed specific IgG responses against wild-type p53 protein. While none of 12 patients with high titer p53 antibody showed spontaneous p53-specific CD8+ T cell responses following a single in vitro sensitization, significant p53-specific IFN-γ producing CD4+ T cells were detected in 6 patients. Surprisingly, similar levels of p53-specific CD4+ T cells but not CD8+ T cells were also detected in 5/10 seronegative cancer patients and 9/12 healthy donors. Importantly, p53-specific CD4+ T cells in healthy donors originated from a CD45RA− antigen-experienced T cell population and recognized naturally processed wild-type p53 protein. These results raise the possibility that p53-specific CD4+ T cells reflect abnormalities in p53 occurring in normal individuals and that they may play a role in processes of immunosurveillance or immunoregulation of p53-related neoplastic events.

A novel cancer/testis antigen KP-OVA-52 identified by SEREX in human ovarian cancer is regulated by DNA methylation

SEREX has proven to be a powerful method that takes advantage of the presence of spontaneous humoral immune response in some cancer patients. In this study, immunoscreening of normal testis and two ovarian cancer cell line cDNA expression libraries with sera from ovarian cancer patients led to the isolation of 75 independent antigens, designated KP-OVA-1 through KP-OVA-75. Of these, RT-PCR showed KP-OVA-52 to be expressed strongly in normal testis, in ovarian cancer cell lines (3/9) and in ovarian cancer tissues (1/17). The expression of KP-OVA-52 in cancer cells is also induced by the demethylating agent 5-aza-2′-deoxycytidine (ADC). To test immunogenicity, we used the Serum Antibody Detection Assay (SADA) to analyze anti-IgG antibodies against the 75 antigens that were initially isolated by SEREX. Four of the 75 antigens (KP-OVA-25, KP-OVA-35, KP-OVA-68 and KP-OVA-73) reacted exclusively with sera from cancer patients. However, KP-OVA-52 reacted with 1 of 20 ovarian cancer sera. These data suggest that the KP-OVA-52 can be considered a novel CT antigen that is regulated by DNA methylation.

HLA superfamily assignment is a predictor of immune response to cancer testis antigens and survival in ovarian cancer

OBJECTIVES To characterize the association between major histocompatibility complex (MHC) types and spontaneous antibody development to the cancer testis (CT) antigen NY-ESO-1. METHODS Tumor expression of NY-ESO-1 and serum antibodies to NY-ESO-1 were characterized in addition to human leukocyte antigen (HLA) type for patients with epithelial ovarian cancer. HLA types were assigned to structure-based superfamilies and statistical associations were examined. HLA types were compared to existing reference libraries of HLA frequencies in a European-Caucasian American population. RESULTS Out of 126 patients identified, 81% were expression positive and 48% had spontaneous antibody responses to NY-ESO-1. There was an association between HLA-B superfamily and seropositivity among patients with tumors expressing NY-ESO-1 (p<0.001). The differences in HLA-B superfamily assignment were driven by HLA-B44. Among all patients, the B27 superfamily was over-represented compared with the general population (p<0.001). CONCLUSIONS HLA type appears to be associated with spontaneous anti-CT antigen antibodies, as well as with the overall risk of ovarian cancer.

Rapid construction of antitumor T-cell receptor vectors from frozen tumors for engineered T-cell therapy

Tumor-specific TCR α and β chain pairs were efficiently identified from a retroviral library of randomly paired TCRs recovered from frozen tumor biopsies and selected by tetramers. Therapeutic T cells expressing these TCRs had potent antitumor activity. T cells genetically engineered with tumor antigen–specific T-cell receptor (TCR) genes have demonstrated therapeutic potential in patients with solid tumors. In order to achieve broader application, an efficient method to identify TCR genes for an array of tumor antigens and HLA restriction elements is required. Here, we have developed a method to construct a TCR-expression library from specimens, including frozen tumor biopsies, that contain antigen-specific T cells. TCR-expressing cassettes were constructed and cloned in a retroviral plasmid vector within 24 hours by unbiased PCR amplification of TCR α and β chain variable regions assembled with TCR constant regions. The method was validated by constructing TCR-expressing vectors from tumor antigen–specific T-cell clones and functionally assessing TCR gene–transduced T cells. We applied this method to frozen ovarian tumor specimens that were infiltrated by tumor antigen–specific T cells. The tumor-derived TCR libraries were expressed in peripheral T cells from healthy volunteers and screened for tumor antigen–specific TCR pairs with the use of an MHC/peptide tetramer reagent. Tumor antigen–specific TCR-expressing transgenes were recovered from isolated tetramer-positive T cells. Peripheral T cells that were engineered with library-derived TCR gene showed potent therapeutic antitumor effect in a tumor xenograft model. Our method can efficiently and rapidly provide tumor-specific TCR-expressing viral vectors for the manufacture of therapeutic and personalized antitumor T-cell products. Cancer Immunol Res; 6(5); 594–604. ©2018 AACR.

Developmentally restricted differentiation antigens are targets for immunotherapy in epithelial ovarian carcinoma.

Developmentally restricted differentiation antigens or cancer-placental antigens, tastin and bystin, are components of an adhesion molecule that plays a critical role in the implantation of the embryo to the uterus. Cell adhesion molecules have been implicated in the metastasis of carcinomas and could be critical targets for immunotherapy in epithelial ovarian carcinomas (EOCs). Our objectives were to define the expression of tastin and bystin proteins in EOCs. Expression of tastin and bystin mRNA in a panel of human tissues and 70 EOC specimens was investigated using qualitative polymerase chain reaction. Amplification products were confirmed by sequencing. Validation of results was performed using immunohistochemical analysis of tastin and bystin applied on a tissue microarray of 202 EOC tissues. The distribution of tastin and bystin expression and clinicopathologic variables were analyzed. Survival probabilities were estimated using the Kaplan–Meier method and statistical significance was determined by performing the logrank test. Expression of tastin and bystin was restricted to placental and testis tissue by qualitative polymerase chain reaction. Of the 70 EOC specimens tested with polymerase chain reaction, 89% and 94% expressed tastin and bystin, respectively. Immunoexpressions of tastin and bystin protein were observed in 69% and 80 % of the ovarian tumors, respectively. Tastin and bystin expression in Stage I/II disease were 66% and 67% compared with 69% and 81% in Stage III/IV disease, respectively. The tissue-restricted expression of tastin and bystin and their abundant expression in EOCs and advanced-stage disease make these developmentally restricted antigens attractive targets for antigen-specific immunotherapy in EOCs.

Abstract LB-18: Statins use prevents ovarian cancer recurrence in women with diabetes mellitus.

Background: Low-density lipoproteins levels are significant predictors of clinical outcomes in ovarian cancer (OvCa) patients. Despite American Diabetes Association (ADA) guidelines, suboptimal hyperlipidemia management is reported in women diagnosed with both OvCa and diabetes mellitus (DM). This study evaluated the impact of cholesterol drugs utilization and importance of following ADA guidelines on OvCa recurrence and survival. Methods: All DM patients newly diagnosed with OvCa between 2003 and 2010 at Roswell Park Cancer Institute were retrospectively reviewed (n=482). A total of 60 newly diagnosed OvCa patients having a form of diabetes at the time of cancer diagnosis were identified. Out of these, 14 patients were excluded due to presence of type 1 diabetes (n=6) or prior cancer history (n=8). The remaining 46 patients were included in the final analyses. Tumor pathology, outcomes, baseline co-morbidities and self-reported drug therapy were documented. Follow-up began at cancer diagnosis and ended with first confirmed recurrence and/or death. Cases lost to follow-up were censored at the date of last contact. To analyze categorical outcomes across different treatment groups, Fisher9s exact test was used. All multivariate analyses were done using Cox proportional hazards models while accounting for age, weight, stage, histology, and cumulative comorbidity. A nominal significance level of 0.05 was used in all testing. Results: Average age at diagnosis and body mass index in this data set was 70±10 years and 34.76±7.07 kg/m2, respectively. Over three quarters of this population was diagnosed with advanced stage OvCa and 96% had a tumor grade of 2 or higher. Roughly two thirds of the tumors evaluated had a serous histology. Out of the cases reviewed, 52% did not receive any form of cholesterol management and 46% received a statin alone or in combination. After a median follow-up of 26.9 months, patients receiving statin monotherapy for cholesterol management were found to have improved recurrence (HR=0.17, 95% CI: 0.04 to 0.73, P=0.02); however, no impact on overall mortality was noted as compared to patients not receiving any cholesterol management medication. Conclusions: This study explored for the first time the association between statin utilization and prognosis in OvCa patients with DM. Given the identified benefit, reinforcing compliance with DM guidelines for hyperlipidemia management in OvCa patients deserves further attention. Our findings seed the beginning of a novel approach in personalized OvCa care. Citation Format: Michelle E. Amsler, Kristina A. Chmiel, Olesya Yaremko, Clare Carroll, Jingjing Yin, Terry Mashtare, Anthony Miliotto, Rachel Brightwell, Kunle Odunsi, Alice C. Ceacareanu. Statins use prevents ovarian cancer recurrence in women with diabetes mellitus. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr LB-18. doi:10.1158/1538-7445.AM2013-LB-18