Immune Therapy In Ovarian Cancer Research Articles

The Use of CAR-T Immune Therapy in Ovarian Cancer

The Use of CAR-T Immune Therapy in Ovarian Cancer

Blocking of CA-MSC-induced desmoplasia reprograms the tumor immune microenvironment and enhances cancer immunotherapy

Abstract Cancer associated MSCs (CA-MSCs) are multipotent stromal cells that generate tumor desmoplasia and promote tumor growth. Here, we investigated the impact of CA-MSCs on the ovarian tumor immune microenvironment. In vitro and in vivo analyses confirmed that CA-MSCs secrete numerous cytokines and chemokines, including Ccl2, Cx3cl1 and Tgfb1, that are known to induce the recruitment of monocytes into the tumor and promote macrophage immunosuppressive phenotype. Using a syngeneic and immune responsive murine ovarian tumor model, we found that CA-MSCs restrict the intra-tumoral trafficking of CD8+ T cells and inhibit the response to immune checkpoint inhibitor therapy. Similarly, in patient samples the presence of CA-MSC is inversely correlated with CD8+ T cell infiltration into tumor islets. Single cell RNAseq analyses revealed that tumoral monocytes and macrophages of a-PD-L1 treated-CA-MSCs enriched tumors express high levels of the protein transforming growth factor beta induced (Tgfbi). In ovarian cancer patient samples TGFBI is primarily expressed in the desmoplastic stroma and correlated with poor prognosis. Importantly, we found that hedgehog signaling inhibitor (HHi) therapy reversed CA-MSC driven tumor desmoplasia, reduced the number of tumor-associated myeloid cells and decreased their expression of Tgfbi. These events restored the infiltration and activation of CD8+ T cells into the tumor islets and response to a-PDL1 therapy. We are currently evaluating the role of Tgfbi in the regulation of innate and adaptive immune response. Our findings demonstrated CA-MSCs critically regulate anti-tumor immunity and support HHi as an adjunct to anti-PDL1 therapy to increase repose to immune therapy in ovarian cancer.

Development of a predictive signatures for immune therapy in ovarian cancer: Whom to treat and whom not to treat?

Objective: To understand the immune landscape of the ovarian cancer (OC) microenvironment and to develop predictive biomarkers to select candidates for immune therapy, we have initiated a study to comprehensively analyze the unique molecular and histopathological characteristics of tumor samples taken during primary debulking and interval debulking and at recurrence.

Three Genes Predict Prognosis in Microenvironment of Ovarian Cancer.

Ovarian cancer (OC) is the deadliest gynecological cancer in women. Immune cell infiltration has a critical role in regulating carcinogenesis and prognosis in OC. To identify prognostic genes relevant to the tumor microenvironment in OC, we investigated the association between OC and gene expression profiles. Results obtained with the ESTIMATE R tool showed that immune score and stromal score were correlated with lymphatic invasion, and high immune score predicted a favorable prognosis. A total of 342 common differentially expressed genes were identified according to the two scores; these genes were mainly involved in immune response, extracellular region, and serine-type endopeptidase activity. Three immune-related prognostic genes were selected by univariate and multivariate Cox regression analysis. We further established a prognostic model and validated the prognostic value of three hub genes in different databases; our results showed that this model could accurately predict survival and evaluate prognosis independent of clinical characteristics. Three hub genes have prognostic value in OC. TIMER analysis revealed that the three genes were correlated with different immune cells. Low levels of macrophage infiltration and high levels of CD4+ T cell infiltration were associated with favorable survival outcomes. Arm-level gain of GYPC was correlated with neutrophils and dendritic cells. These findings indicate that CXCR4, GYPC, and MMP12 modulate prognosis via effects on the infiltration of immune cells. Thus, these genes represent potential targets for immune therapy in OC.

Abstract B01: Optimizing chemotherapy for the integration of immune therapy in ovarian cancer: Enriching effector T cells in the peritoneal tumor microenvironment using the route of cisplatin administration (IV vs. IP)

Abstract Background/Objective: Despite its success in treating other tumor types, immune therapy has underperformed in ovarian cancer. One reason may be the residual effects from prior treatment. Standard therapy of ovarian cancer includes surgery and platinum-based chemotherapy administered intravenously (IV) or intraperitoneally (IP). IP cisplatin results in higher concentrations of drug in the peritoneal cavity compared to IV. With evidence from our lab that peritoneal lymphocytes have a significant impact on treatment efficacy in ovarian cancer models, we sought to determine the impact of the route of cisplatin administration on local T-cell subsets. Our long-term goal is to identify strategies to optimally integrate immune therapy with current treatment regimens. Methods: For these experiments, we used the syngeneic ID8ova murine model of high-grade serous ovarian cancer, which constitutively expresses ovalbumin. The in vitro effects of cisplatin on peritoneal T cells from tumor-bearing mice in culture were evaluated by flow cytometry. For in vivo experiments, mice received cisplatin (3mg/kg every 3 days x 4 doses) IV or IP starting on day 14 after tumor challenge. Peritoneal and peripheral T cells were harvested on day 1, 8, and 14 after treatment and used to analyze activation status, tumor specificity, and PD-1 immune checkpoint expression between IV and IP treated groups using flow cytometry. Results: Exposing peritoneal lymphocytes to 100 μg/ml of cisplatin ex vivo enriched for CD8+ T cells with an effector and central memory phenotype [52.7% vs. 29.3% for untreated cells, p=0.001]. This was due to the disproportionate death of naïve cells, rather than phenotype switching. In vivo, we found that 15 days after treatment IP cisplatin increases the percent of effector CD8+ cells relative to IV cisplatin treatment [72.8% IP vs. 43.5% IV cisplatin (p=0.038)], and CD8+ cells expressing PD1 [45.80 % IP vs. 17.98% IV cisplatin (p=0.006)]. Changes in antigen-specific cells were trending, but not significant [38.29 % IP vs. 20.45% IV cisplatin, respectively (p=0.07)]. These changes were not seen in circulating lymphocytes. Interpretation/Conclusions: Our results indicate that IP cisplatin enriches activated tumor-specific effector cells in the ovarian tumor environment. This effect is dose dependent and results from high local concentrations of cisplatin following IP administration. While the role of IP chemotherapy for ovarian cancer has come under scrutiny based on recent clinical trials, our data showing an increase in effector cells and expression of the inhibitory checkpoint receptor PD-1 suggest that IP cisplatin administration could positively prime the peritoneal tumor environment to enhance the efficacy of immune therapy in ovarian cancer. Citation Format: Henning S. De May, Sharina Palencia Desai, Ichiko Kinjyo, Sarah F. Adams. Optimizing chemotherapy for the integration of immune therapy in ovarian cancer: Enriching effector T cells in the peritoneal tumor microenvironment using the route of cisplatin administration (IV vs. IP) [abstract]. In: Proceedings of the AACR Special Conference on Advances in Ovarian Cancer Research; 2019 Sep 13-16, 2019; Atlanta, GA. Philadelphia (PA): AACR; Clin Cancer Res 2020;26(13_Suppl):Abstract nr B01.

Adoptive cell therapy in combination with checkpoint inhibitors in ovarian cancer.

Immune therapy is a promising field within oncology but has been unsuccessful in ovarian cancer (OC). Still, there is rationale and evidence supporting immune therapy in OC. We investigated the potential for adoptive cell therapy (ACT) from in vitro expanded tumor-infiltrating lymphocytes (TILs) in combination with checkpoint inhibitors (ICI) and conducted immunological testing of ex vivo expanded TILs (REP-TILs).Six patients with late-stage metastatic high-grade serous OC were treated with immune therapy consisting of ipilimumab followed by surgery to obtain TILs and infusion of REP-TILs, low-dose IL-2 and nivolumab.One patient achieved a partial response and 5 others experienced disease stabilization for up to 12 months. Analysis of the REP-TILs with flow- and mass-cytometry show primarily activated and differentiated effector memory T cells. REP-TILs showed in vitro reactivity and expression of inhibitory receptors, such as LAG-3 and PD-1. Furthermore, our data indicate that addition of ipilimumab therapy improves the T cell fold expansion during production, increase the level of CD8 T cell tumor reactivity, and favorably affect the T cell phenotype.We show that the combination of ICI and ACT is feasible and safe. With one partial response and one long-lasting SD, we demonstrated the potential of ACT in OC.

LPS and IL-8 activated umbilical cord blood-derived neutrophils inhibit the progression of ovarian cancer.

Background: Immunotherapy including immune checkpoint blockade, cancer vaccines, and adoptive cell therapy. However, no immune therapies support ovarian cancer. It is not clear whether the neutrophils, the component of the immune system derived from umbilical cord blood play a role in inhibiting the progression of ovarian cancer.Methods: We investigate the impact of LPS and IL-8 activated neutrophils derived from umbilical cord blood(UCB)on ovarian cancer progression. After co-culture LPS and IL-8 activated UCB-derived neutrophils with ovarian cancer cell line SKOV3 and OVCAR3, CCK8, Transwell assay, and Flow Cytometry was performed to detect cell proliferation, migration, invasion, and apoptosis of ovarian cancer cell lines SKOV3 and OVCAR3. Furthermore, RT-PCR and western blotting assay were used to analyze the mechanism of metastasis and apoptosis of ovarian cancer cell lines respectively to support previous function experiments.Results: We demonstrate LPS and IL-8 activated neutrophils derived from umbilical cord blood inhibit proliferation, invasion migration and promote apoptosis of SKOV3 and OVCAR3. Meanwhile, LPS and IL-8 activated UCB-derived neutrophils significantly decreased BAX and increased BCL2 expression in SKOV3 and OVCAR3 which account for the mechanism of apoptosis. Moreover, LPS and IL-8 activated UCB derived neutrophils significantly up-regulated E-cadherin and downregulated N-cadherin, MMP2 expression in SKOV3 and OVCAR3.Conclusion: Taken together, these results approved that LPS and IL-8 activated neutrophils from UCB may be the novel strategy in immune therapy for ovarian cancer.

In Search of a Novel Immune Therapy for Ovarian Cancer

In Search of a Novel Immune Therapy for Ovarian Cancer

Abstract 1395: HDAC6 and DNMT inhibition affect immunogenicity of ovarian cancer cells: A rationale for combining epigenetic and immune therapy in ovarian cancer

Abstract Background: Therapies that activate the immune system to fight cancer have shown robust responses in solid tumors. However, most patients, including those with ovarian cancer, do not respond to these therapies alone. Drugs that inhibit epigenetic modifiers increase immune signaling from cancer cells. Epigenetic modifiers DNA methyltransferase inhibitors (DNMTi) and selective histone deacetylase inhibitors (HDACi),in particular selective HDAC6i, modulate immune-related pathways involved in anti-tumor immune responses. HDAC6i downregulate immunosuppressive ligands PD-L1 and PD-L2 via dephosphorylating pSTAT3 and upregulate tumor associated antigens (TAA) and antigen presentation machinery. Similarly, DNMTi activate anti-viral signaling via expression of Endogenous Retroviruses (ERVs) to trigger the type I interferon response, upregulate tumor antigen processing and presentation, and stimulate pro-inflammatory cytokines. The aim of our study is to test if the combination of epigenetic modulators Nexturastat A (Next A), a selective HDAC6i, and 5-azacytidine (AZA), a DNMTi, can be safely used to increase an immune response in ovarian cancer. We hypothesize that these drugs will enhance tumor immunity alone and when combined with immune checkpoint blockades targeting PD-1. Results: HDAC enzymes are differentially expressed in A2780, HEY, OVCAR3, SKOV3, and TYKNu human ovarian cancer cell lines. HDAC1 and HDAC2 proteins were similarly expressed in HEY and SKOV3 whereas HDAC6 was expressed at lower levels in HEY and TYKNu but at higher levels in SKOV3, OVCAR3, and A2780. As previously reported we believe this may be due to the presence of the chromatin modifier ARID1A mutation in the SKOV3 and A2780 cell lines. The upregulation of HDAC6 also correlated with a higher IC50 for NextA treatment in those particular cell lines. Further immunoblots showed that PD-L1, a marker of poor prognosis in ovarian cancer, decreased after treatment with NextA and even more in combination with AZA. Additionally, DNMT1, the known target of AZA, was decreased after treatment with AZA and NextA, both independently and in combination, a finding that has not been previously reported. Conclusions: As shown previously, HDAC6 enzyme levels are higher in cell lines with ARID1A mutations. DNMT1 was decreased after treatment with AZA, as expected, but surprisingly also after treatment with NextA. PD-L1 decreased after treatment with NextA and even more so when combined with AZA. We thus believe that combining these two epigenetic modifiers will lead to an additive effect on immune signaling through stimulation of antiviral signaling (DNMTi), which can upregulate the immunosuppressive ligand PD-L1, which is then reduced by HDAC6 inhibition. We are currently testing the combination of both epigenetic modifiers with anti-PD-1 in an immunocompetent mouse model of ovarian cancer. Citation Format: Aneil P. Srivastava, Sara M. Moufarrij, Melissa Hadley, Sarah Chisholm, Micael Lopez-Acevedo, Alejandro Villagra, Katherine B. Chiappinelli. HDAC6 and DNMT inhibition affect immunogenicity of ovarian cancer cells: A rationale for combining epigenetic and immune therapy in ovarian cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1395.

Abstract 3208: Chemo-induced biology of PD-L1 and in vivo combination immune therapy for ovarian cancer

Abstract Rationale: Ovarian cancer patients receive platinum/taxane-based chemotherapy as standard of care. Five year survival has remained unchanged for several decades, at less than 45%, pointing to the need for new and improved therapies. We recently reported in vivo anti-tumor efficacy of PD-L1 immune checkpoint blockade in a new transplantable ovarian cancer mouse model. However, chemo-induced effects on ovarian tumor PD-L1 expression have not been addressed. We studied here the effect of platinum/taxane on tumor PD-L1 expression in vitro and in vivo and tested the efficacy of PD-L1 blockade in combination with cisplatin, using several treatment regimens. Methods and Results: Our results demonstrate that in vitro exposure of several human ovarian cancer cell lines, with various baseline susceptibilities to cisplatin and taxol, triggers PD-L1 upregulation. Similar effects were observed when newly tumor-derived, platinum sensitive (2F8) and platinum resistant (2F8cis) murine ovarian cancer cell lines were exposed to chemo drugs in vitro. Based on these findings we postulated that PD-L1 immune checkpoint blockade in combination with cisplatin may provide therapeutic benefit in ovarian cancer. In vivo, we have challenged n = 37 mice IP with 0.8 million 2F8 cells. Tumor-bearing mice were treated with cisplatin, anti-PD-L1 antibody, both drugs or isotype control every two weeks for three doses starting at day 14 post-inoculation. Study endpoint was overall survival. Secondary endpoints were tumor CD8 infiltration, changes in Th1/cytotoxic immunity. Tumors and ascites-derived cancer cells were analyzed with flow cytometry. RNA was extracted from splenocytes and analyzed with Nanostring using probes for n = 511 immune genes. In line with in vitro results, tumor cells isolated ex vivo from cisplatin-treated mice expressed increased PD-L1. Compared to control treated mice, both Cisplatin alone and anti-PD-L1 alone increase overall survival (p = 0.002 and p = 0.02, respectively). No increase in survival was observed in anti-PD-L1/Cisplatin-treated mice, due to an over-responsive immune cascade overwhelming the animal. Addition of celecoxib, a cyclooxygenase-2 inhibitor, to the anti-PD-L1/cisplatin combination was well tolerated and led to improved overall survival. Conclusion: Ovarian cancer cells upregulate PD-L1 in response to chemotherapy exposure in vivo and in vitro. Though effective independently, combination cisplatin and anti-PD-L1 blockade did not improve survival, likely due to cytokine release syndrome. Celecoxib added to cisplatin and anti-PD-L1 improves overall survival. Anti-tumor immunity in responder mice revealed a cytotoxic T cell mediated gene signature. These findings reveal benefits and pitfalls of chemotherapy in combination with immune checkpoint blockade and have high translational potential for ovarian cancer treatment. Citation Format: Shannon Grabosch, Feitianzhi Zeng, Lixin Zhang, Tianzhou Ma, George Tseng, Robert P. Edwards, Anda M. Vlad. Chemo-induced biology of PD-L1 and in vivo combination immune therapy for ovarian cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 3208.

Chemo-induced biology of PD-L1 and in vivo combination immune therapy for ovarian cancer

Chemo-induced biology of PD-L1 and in vivo combination immune therapy for ovarian cancer

Ovarian cancer from an immune perspective.

Despite major advances in the treatment of ovarian cancer over the past two decades, it is still an incurable disease and requires the development of better treatment strategies. In recent years, we have developed a greater understanding of tumor immunology and the interactions between tumors and the immune system. This has led to the emergence of cancer immunotherapy as the fourth treatment modality in cancer. In this article, we address the principles of immunotherapy and different approaches that have been investigated over the past decade and discuss the future of immune therapy in ovarian cancer.

Double-loaded mature dendritic cell (DC) therapy for non-HLA-restricted patients with advanced ovarian cancer: Final results of a clinical phase I study.

3052 Background: Prognosis of ovarian cancer remains poor after initial responsiveness to surgery and chemotherapy followed by high recurrence and mortality rates and new experimental approaches are warranted. Our goal was to evaluate a novel DC-based vaccine, which exploits a unique dual loading strategy to amplify specific anti-tumor short- and long-term immune responses to delay or even prevent recurrent and metastatic disease. Methods: Monocytes were collected via apheresis, matured into DCs and pulsed with two universal tumor associated antigens (uTAA) in our GMP facility. DCs were loaded with TERT and Survivin via two different pathways (mRNA and peptide) to elicit CD8+ and CD4+T cells directly. Endpoints of the study were tolerability and safety, immunological and clinical responses. T cell responses against the IMP and loaded antigens were evaluated by cytokine bead array (CBA) and intracellular staining assays. Results: 15 non HLA-restricted patients with advanced ovarian cancer were enrolled 8 weeks after standard treatment (surgery and chemotherapy). Each patient was vaccinated intradermally on a weekly or fortnightly basis with a maximum of 8 doses of 13*106 double loaded DCs. The majority of treatment related side effects were grade 1 fever and erythema. Overall the therapy was well tolerated. Immune response data is available for 14/15 patients, 1 was withdrawn after the first administration. The IMP leads to strong immune responses with high frequency (>90%), which is proven for both uTAAs in CD8+ as well as CD4+ T cells. A clear positive trend in progression free survival is demonstrated compared to matched historical control. Conclusions: Therapy with our unique double loaded DC vaccine was feasible, safe and well-tolerated by patients. The vaccine was highly immune stimulatory and elicited both, long-term and short-term anti-tumor immune responses, establishing a promising platform for immune therapy for ovarian cancer and all solid tumors in general. The first two authors contributed equally. Clinical trial information: NCT01456065.

Immune Therapy for Ovarian Cancer: Promise and Pitfalls

This review covers immune and anatomic considerations specific for ovarian cancer immune therapy. Prior approaches and potential reasons for lack of better efficacy are discussed, along with newer approaches in pre-clinical and early clinical development. Potential means for future investigations and means to integrate immune with other approaches are discussed.