Examining the evidence for immune checkpoint therapy in high-grade serous ovarian cancer

Antigen presentation potential is variable among human ovarian tumour and syngeneic murine models and dictates pre-clinical outcomes of immunotherapy

High grade serous ovarian carcinoma (HGSC) is a fatal gynaecological malignancy with limited therapeutic options. Immunotherapies targeting MHC-I-dependent antigen presentation offer potential. Currently, the antigen presentation machinery (APM) of widely used syngeneic murine HGSC models remains poorly characterised, limiting translational relevance. Here, we systematically evaluate APM gene expression in syngeneic murine and patient samples. Tap1 and Psmb8 were identified as critical APM markers, deficient in murine models and strongly correlating with MHC-I expression. Hierarchical clustering correlation analysis using these markers revealed that ID8-p53⁻/⁻BRCA1⁻/⁻ was the most strongly correlated model and aligned with the largest patient subset. Moreover, ID8-ip1 correlated to the smaller second patient subset strongly. The low MHC-I expressing IG10 model was unique clustering alongside patient derived LP28 tumour and not fitting either patient subset. In vivo test of a novel combination immune therapy consisting of Flt3L, Poly(I:C), and paclitaxel therapy demonstrated significantly reduced tumour burden in high APM models (p53⁻/⁻BRCA1⁻/⁻, ID8-ip1; p < 0.01), but not IG10. Furthermore, high expressing MHC-I models were linked to enhanced DC expansion, CD8⁺ T-cell infiltration, and effector differentiation (131 % increase in ID8-ip1), alongside improved CD8⁺ T-cell activation and CD86⁺ B-cell co-stimulation. These findings establish MHC-I as a predictive biomarker for immunotherapy response and underscore the need for APM-enhancing strategies in antigen-poor tumours. By bridging murine models to human APM heterogeneity, this work provides a framework for optimising preclinical immunotherapy evaluation and patient stratification, advancing tailored therapeutic approaches for HGSC.

Interleukin-6 Is a Crucial Factor in Shaping the Inflammatory Tumor Microenvironment in Ovarian Cancer and Determining Its Hot or Cold Nature with Diagnostic and Prognostic Utilities

Ovarian cancer (OC) remains the leading cause of cancer-related deaths among women, often diagnosed at advanced stages due to the lack of effective early diagnostic procedures. To reduce the high mortality rates in OC, reliable biomarkers are urgently needed, especially to detect OC at its earliest stage, predict specific drug responses, and monitor patients. The cytokine interleukin-6 (IL6) is associated with low survival rates, treatment resistance, and recurrence. In this review, we summarize the role of IL6 in inflammation and how IL6 contributes to ovarian tumorigenesis within the tumor microenvironment, influencing whether the tumor is subsequently classified as "hot" or "cold". We further dissect the molecular and cellular mechanisms through which IL6 production and downstream signaling are regulated, to enhance our understanding of its involvement in OC development, as well as OC resistance to treatment. We highlight the potential of IL6 to be used as a reliable diagnostic biomarker to help detect OC at its earliest stage, and as a part of predictive and prognostic signatures to improve OC management. We further discuss ways to leverage artificial intelligence and machine learning to integrate IL6 into diverse biomarker-based strategies.

Transforming treatment paradigms: Focus on personalized medicine for high-grade serous ovarian cancer

High-grade serous ovarian cancer (HGSOC) is the most common and aggressive subtype of ovarian cancer, accounting for approximately 70% of all ovarian cancer cases and contributing significantly to the high mortality rates associated with this disease. Because of the asymptomatic nature of early stage disease, most patients are diagnosed at advanced stages when the cancer has already spread into the abdominal cavity, requiring complex and intensive surgical and chemotherapeutic interventions followed by maintenance therapies. Although a minority of cases are associated with well defined genetic syndromes, specific risk factors and a clear etiology in many cases remain elusive. HGSOC tumors are characterized by a high frequency of somatic gene copy number alterations, often associated with defects in homologous recombination repair of DNA. All attempts to introduce an effective screening for HGSOC to date have been unsuccessful. This review elucidates the complexities surrounding HGSOC and encompasses its etiology, epidemiology, classification, pathogenesis, and the current array of treatment strategies. Understanding molecular underpinnings is crucial for the development of targeted therapies and personalized multimodal treatment approaches in centralized therapeutic structures. This review also examines the importance of the tumor microenvironment. In addition, the authors' objective is to underscore the critical importance of placing the patient's perspective and diversity at the forefront of therapeutic strategies, thereby fostering a genuinely participatory decision-making process and ultimately improving patient quality of life.