Curtis, Marion

Abstract Global incidence and mortality rates for endometrial and cervical cancers have been steadily rising, while these rates for ovarian cancer have decreased. Although these cancers represent unique diseases and challenges, overlapping biology and responses to targeted and immunotherapies create opportunities to advance research through shared knowledge and resources. In 2025, investigators funded by National Cancer Institute (NCI) Specialized Programs of Research Excellence (SPORE) and other NCI-supported grants convened a hybrid meeting to identify challenges and knowledge gaps in translational research, highlight advances, define shareable resources and technologies, and foster collaboration among the Gynecologic Cancer SPORE sites, patient advocates, and NCI staff. Special sessions were arranged for presentations by Patient Advocates, Early-stage Investigators, Investigators Transitioning to Gynecologic Cancer Research. Meeting-wide workshops on Sharing Resources and Reducing Time to Activation of Clinical Trials and networking events were included. Collectively, the presentations converged on three overarching themes: (i) interception and early disease biology, (ii) development of innovative targeted and immune-based therapies, (iii) critical role of shared resources and collaborative infrastructure in accelerating translational progress. The unifying theme across disease sites was molecular advances to improve early detection/prevention and to drive therapeutic advancements. Novel findings discussed included: candidate precursor cells and mechanisms of high grade serous ovarian cancer development; therapeutic vaccines and their delivery methods for cervical dysplasia; identification of immune-targetable ovarian cancer antigens; various novel molecularly targeted drugs and immune-based agents for endometrial and ovarian cancers; and approaches to bypass drug resistance. Workshops delineated actionable strategies to further advance gynecologic cancer translational research.

ABSTRACT Interferon-γ (IFNγ) signaling is prominent in inflammatory CNS microenvironments across many neurological disorders, but the neuronal peptides presented on HLA class I under these conditions and their functional consequences for CD8 + T cells remain incompletely defined. Here we combine human iPSC-derived human neural aggregates (HNAs), HLA class I immunoprecipitation coupled to LC-MS/MS immunopeptidomics, and microfluidic co-culture assays to map IFNγ-induced neuronal antigen presentation and test antigen-specific cytotoxicity. IFNγ stimulation induced robust HLA class I expression in HNAs and enabled recovery of a canonical 8-12-mer class I ligandome enriched for 9-mers. Neuron-restricted expression of a synapsin-driven polyepitope cassette yielded presentation of defined neoantigen 9-mer peptides on donor HLA class I molecules and, in the presence of IFNγ, elicited activation of autologous antigen-specific CD8 + T cells and consequent antigen-dependent neurite injury. Across four donors, comparative immunopeptidomics identified large IFNγ-unique neural peptide repertoires distinct from matched fibroblasts and revealed a consistent enrichment of predicted high-affinity binders on HLA-B allotypes. Finally, β2-microglobulin deletion ablated peptide recovery, and neuron-restricted β2-microglobulin reconstitution enabled identification of neuron-derived peptides, including peptides derived from neurofilament light (NEFL) that were shared across donors and presented on multiple HLA allotypes. Together, these data provide an integrated platform for neuronal autoantigen discovery and functional validation and support a model in which IFNγ-driven neuronal HLA class I presentation creates an HLA-B-weighted epitope landscape that can be recognized by autoreactive cytotoxic CD8 + T cells.

Abstract Despite advances in immunotherapy, high-grade serous ovarian cancer (OC) remains largely refractory to current treatments. The diversity of antigens expressed in OC has not been fully elucidated, limiting targeted approaches. Using immunopeptidomic profiling of HLA-A02:01+ OC cell lines and metastatic patient samples, we sought to identify a broader range of actionable antigens. Among canonical tumor-associated peptides, we found epitopes from TTLL8, POTEE, and PKMYT1—proteins with minimal expression in normal tissues but elevated in OC. TTLL8, in particular, correlated with poor prognosis and elicited robust CD8+ T cell responses, underscoring its immunogenic potential. In a separate study, we detected 311 cryptic (noncanonical) peptides derived from noncoding genomic regions across five metastatic OC tumor samples. Although representing <1% of total peptides, these cryptic antigens dominated the immunogenic landscape, with nearly 70% inducing autologous CD8+ T cell activation, as measured by 4-1BB and IFN-γ expression. Together, these findings expand the antigenic repertoire of OC and support the development of new immunotherapies targeting both canonical and cryptic tumor antigens. Citation Format: Marion Curtis. Cracking the code: Identifying immunogenic targets in high-grade serous ovarian cancer [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Ovarian Cancer Research; 2025 Sep 19-21; Denver, CO. Philadelphia (PA): AACR; Cancer Res 2025;85(18_Suppl):Abstract nr IA019.

Abstract Background: Despite the success of chimeric antigen receptor (CAR) T cell therapy in hematological malignancies, its efficacy in solid tumors remains limited. Macrophages, as key players in the innate immune response, offer unique advantages in the solid tumor context due to their ability to infiltrate tissues and phagocytose tumor cells. Preclinical studies have demonstrated that CAR-engineered macrophages (CAR-Ms) can penetrate solid tumors, initiate phagocytosis, and promote adaptive immunity. Early-phase clinical trials infusing CAR-Ms into patients have shown a favorable safety profile. However, within the immunosuppressive tumor microenvironment (TME), macrophages are often reprogrammed into tumor-promoting, M2-like tumor-associated macrophages (TAMs), which limit their therapeutic efficacy. Metabolic reprogramming is a critical driver of this polarization and TCA derived succinate has been shown to promote M1 phenotype in macrophages. In this study, we investigate whether succinate-loaded nanoparticles (PES NPs) can metabolically rewire CAR-Ms to maintain a pro-inflammatory (M1-like) phenotype and enhance antitumor activity in ovarian cancer (OC). Results: We synthesized polyethylene succinate (PES) nanoparticles (NPs) and analyzed their size, polydispersity, and zeta (ζ) potential using dynamic light scattering (DLS). The results showed a negative potential, indicative of stability, and suggested that succinate could be effectively encapsulated in nanoparticles. OC cells abundantly express mesothelin protein; therefore, mesothelin-targeting CARs were chosen to transfect mouse bone marrow-derived macrophages (BMDMs) or human monocyte-derived macrophages (HMDMs) to generate CAR-Ms. Our results showed that mouse and human CAR-Ms treated with PES NPs exhibited increased mitochondrial respiration and glycolysis, seen as elevated ECAR and OCR relative to vehicle control or cell-permeable dimethyl succinate ester (DMSA). Flow cytometry analysis revealed that PES treatment resulted in increased expression of markers of the classical M1 phenotype in both mouse and human CAR-Ms. The CAR-Ms also had elevated mRNA levels of proinflammatory cytokines like IL-6, TNFα, and IL1β, while anti-inflammatory cytokines like IL-10 remained low. Furthermore, IL-4-induced M2-like CAR-Ms could be reversed to an M1-like phenotype by PES NPs. Consistent with these results, PES NP-treated CAR-Ms exhibited increased phagocytic activity toward OC cells expressing mesothelin. Building on these in vitro results, the effect of PES NP-treated CAR-Ms on the reduction of tumor growth in OC tumor models will be further investigated. Conclusions: Our findings demonstrate that PES NPs effectively reprogram CAR-Ms to maintain a pro-inflammatory M1 phenotype. This reprogramming enhances their phagocytic activity and target cell killing in vitro. Collectively, these results support intracellular succinate delivery as a promising strategy to improve the efficacy of CAR-M-based therapies in OC. Citation Format: Remya Raja, Alexis Hand, Madhan Mohan Chandra Sekhar Jaggarapu, Jason Tonne, Richard Vile, Abhinav Acharya, Marion Curtis. Succinate based metabolic reprogramming of CAR-macrophages for ovarian cancer immunotherapy [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Ovarian Cancer Research; 2025 Sep 19-21; Denver, CO. Philadelphia (PA): AACR; Cancer Res 2025;85(18_Suppl):Abstract nr B063.

Increased infiltration of CD3 + and CD8 + T cells into ovarian cancer (OC) is linked to better prognosis, but the specific antigens involved are unclear. Recent reports suggest that HLA class I can present peptides from noncoding genomic regions, known as noncanonical or cryptic peptides, but their immunogenicity is underexplored. To address this, we used immunopeptidomic analysis and RNA sequencing on five metastatic OC samples, which identified 311 cryptic peptides (40 to 83 per patient). Despite comprising less than 1% of total peptides, cryptic peptides from noncoding transcripts emerged as the predominant antigen class when compared to the other major classes of known tumor-specific and tumor-associated antigens in OC samples. Notably, nearly 70% of the prioritized cryptic peptides elicited T cell activation, as evidenced by increased 4-1BB and IFN-γ expression in autologous CD8 + T cells. This study reveals noncoding cryptic peptides as an important class of immunogenic antigens in OC.

Abstract Rheumatoid arthritis (RA) causes immunological and metabolic imbalances in tissue, exacerbating inflammation in affected joints. Changes in immunological and metabolic tissue homeostasis at different stages of RA are not well understood. Herein, the changes in the immunological and metabolic profiles in different stages in collagen induced arthritis (CIA), namely, early, intermediate, and late stage is examined. Moreover, the efficacy of the inverse‐vaccine, paKG(PFK15+bc2) microparticle, to restore tissue homeostasis at different stages is also investigated. Immunological analyses of inverse‐vaccine‐treated group revealed a significant decrease in the activation of pro‐inflammatory immune cells and remarkable increase in regulatory T‐cell populations in the intermediate and late stages compared to no treatment. Also, glycolysis in the spleen is normalized in the late stages of CIA in inverse‐vaccine‐treated mice, which is similar to no‐disease tissues. Metabolomics analyses revealed that metabolites UDP‐glucuronic acid and L‐Glutathione oxidized are significantly altered between treatment groups, and thus might provide new druggable targets for RA treatment. Flux metabolic modeling identified amino acid and carnitine pathways as the central pathways affected in arthritic tissue with CIA progression. Overall, this study shows that the inverse‐vaccines initiate early re‐establishment of homeostasis, which persists through the disease span.

Abstract Even though it is known that the immune response is highly relevant in ovarian cancer (OC), as demonstrated by the strong association between tumor infiltration by CD8 T cells and overall survival in high grade serous ovarian cancer, immunotherapy has not yet benefited patients with this disease. Therefore, there is a critical unmet need to identify new therapeutic targets and approaches that will improve outcomes for women with resistant disease. We used a novel culture system that uses a two-step activation process to elicit tumor-specific Type 1 (tumor-killing) T cells from the peripheral blood of OC patients. Briefly, the T cells are stimulated over the first two days with GM-CSF, MUC1 peptide antigens, and Toll-like receptor agonists (TLRa). After the second day in culture, the cells are washed and cultured in media containing IL-7 for the next 17 days. Using peripheral blood mononuclear cells (PBMCs) from 4 ovarian cancer patients, who had undergone between 1-3 prior lines of therapy, we have shown that all 4 were successfully activated and expanded with MUC1 antigens. Overall, the CD3+ cell population expanded from 5.7 – 12.6 fold over the 19 day culture, which was consistent with the sample from a healthy donor. Intracellular cytokine staining for IFNγ was used to determine MUC1-specific T cell responses at day 19. All OC patient T cells had increased reactivity to the MUC1-peptides as compared to the negative control peptide. Total MUC1-specificity ranged from 9.6 – 30.1% in CD4+ T cells and 6.6 – 16.8% in CD8+ T cells. We additionally performed high-parameter mass cytometry by time of flight (CyTOF) analysis using 34 antibodies targeting surface and intracellular markers. The FlowSOM algorithm followed by Marker Enrichment Modeling were used to identify major clusters of T cells and their associated phenotypes. Using this approach 12 major clusters of T cells were identified and overlayed on a tSNE plot. Of the 12 clusters, 7 represented CD8+ T cells and 5 represented CD4+ T cells. The day 19 clusters primarily represented T effector cells, T effector memory, and T central memory cells. The majority of day 19 cells expressed markers of effector function, including T-bet, EOMES, GRANZ-B, and GRANZ-K, which were present in both CD8+ and CD4+ populations. Exhaustion and regulatory markers were found to be low or absent in the day 19 cells. These results demonstrate that highly polyfunctional T cells with memory markers are generated from our innovative culture system using PBMCs from OC patients. These results provide preclinical evidence that will support future clinical trials of adoptive cell therapy using this culture system in OC. Citation Format: Brenda Ernst, Latha Pathangey, Michael Gustafson, Sandra Gendler, Marion Curtis. Rapid expansion of natural, MUC1-activated T cells from the peripheral blood of ovarian cancer patients for adoptive cell therapy [abstract]. In: Proceedings of the AACR Special Conference on Ovarian Cancer; 2023 Oct 5-7; Boston, Massachusetts. Philadelphia (PA): AACR; Cancer Res 2024;84(5 Suppl_2):Abstract nr A086.

Abstract Background: Increased infiltration of T cells into ovarian tumors has been repeatedly shown to be predictive of enhanced patient survival. However, despite the evidence of an active immune response in OC, immune checkpoint blockade therapy has been ineffective. Recently studies have shown that deficiencies in the DNA damage response (DDR) can drive increased genomic instability and tumor immunogenicity. One target involved in the DDR that has the potential to be of therapeutic value is protein phosphatase 4 (PP4); however, the effect of PP4 deficiency on anti-tumor immunity remain unknown. Results: Our results show that PP4 inhibition combined with carboplatin leads to increased carboplatin sensitivity, DNA damage, and micronuclei formation. Using a panel of ovarian cancer cells, we show that PP4 inhibition triggers inflammatory signaling via NF-κB and STAT1 activation resulting in increased expression of pro-inflammatory cytokines including IFNβ1, CCL5, CXCL10, and IL-6. Moreover, conditioned media from OC cells treated with the combination of PP4 inhibitor and carboplatin significantly increased migration of both CD8 T cell and NK cells over carboplatin treatment alone. Knockdown of STING in OC cells significantly abrogated the increase in CD8 T cell migration induced by PP4 inhibition. PPP4C or PPP4R3B knockdown resulted in strong induction of NK cell IFN-γ, increased degranulation, and increased NK cell-mediated cytotoxicity against OC cells. Stable knockdown of PP4C in a syngeneic, immunocompetent mouse model of ovarian cancer resulted in significant reduction of tumor growth in vivo. PP4C low tumors had increased infiltration of CD161+ NK cells and CD4+ T cells. Addition of low dose carboplatin treatment in vivo led to increased CD8+ T cell infiltration in PP4C low tumors when compared to the untreated groups. Conclusions: Our work has identified a role for PP4 inhibition in promoting anti-tumor immune activation. These findings provide the rationale for combining PP4 inhibitors with immunotherapy as a new approach in ovarian cancer treatment. Citation Format: Remya Raja, Christopher Wu, Esen Y. Bassoy, Thomas Rubino, Emma Utagawa, Paul Magtibay, Kristina Butler, Marion Curtis. Protein phosphatase 4 inhibition stimulates anti-tumor immunity in ovarian cancer. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 4455.