Pembrolizumab in patients with programmed death ligand 1-positive advanced ovarian cancer: Analysis of KEYNOTE-028

Identification of TTLL8, POTEE, and PKMYT1 as immunogenic cancer-associated antigens and potential immunotherapy targets in ovarian cancer

Most high-grade serous ovarian cancers (OC) do not respond to current immunotherapies. To identify potential new actionable tumor antigens in OC, we performed immunopeptidomics on a human OC cell line expressing the HLA-A02:01 haplotype, which is commonly expressed across many racial and ethnic groups. From this dataset, we identified TTLL8, POTEE, and PKMYT1 peptides as candidate tumor antigens with low expression in normal tissues and upregulated expression in OC. Using tissue microarrays, we assessed the protein expression of TTLL8 and POTEE and their association with patient outcomes in a large cohort of OC patients. TTLL8 was found to be expressed in 56.7% of OC and was associated with a worse overall prognosis. POTEE was expressed in 97.2% of OC patients and had no significant association with survival. In patient TILs, increases in cytokine production and tetramer-positive populations identified antigen-specific CD8 T cell responses, which were dependent on antigen presentation by HLA class I. Antigen-specific T cells triggered cancer cell killing of antigen-pulsed OC cells. These findings suggest that TTLL8, POTEE, and PKMYT1 are potential targets for the development of antigen-targeted immunotherapy in OC.

Neo-adjuvant pembrolizumab in stage IV high-grade serous ovarian cancer: the phase II Neo-Pembro trial

While immune checkpoint inhibitors (ICIs) have revolutionized cancer treatment, their efficacy in high-grade serous ovarian cancer (HGSOC) remains limited. Some patients, however, achieve lasting responses, emphasizing the need to understand how tumor microenvironment and molecular characteristics influence ICI response. The phase 2 Neo-Pembro study (NCT03126812) included 33 untreated stage IV HGSOC patients, who were scheduled for 6 cycles of carboplatin-paclitaxel and interval cytoreductive surgery. Pembrolizumab (pembro) was added from cycle two and continued for one year. The primary objective was to assess intratumoral immune activation using multiplexed immunofluorescence and immune-related gene expression. Our findings show immune activation, evidenced by an increase in CD3 + , CD8 + , CD8 + /FOXP3+ ratio, TNF-α and interferon-γ signaling. Treatment was well-tolerated. We observed major pathologic responses in 9/33 patients (27%, 95%CI 14-46), with pathologic response strongly associated with immune activation and OS. At a median follow-up of 52.8 months, 8/9 major responders were alive, with 6 patients recurrence-free. In contrast, 4/24 minor responders survived, including one recurrence-free. ctDNA clearance was observed in all major responders and was associated with prolonged PFS and OS. PD-L1 expression and homologous recombination deficiency were predictive of major response and may serve as biomarkers, warranting further exploration. These results suggest major responders may benefit from neo-adjuvant pembro.

The multiple facets of ovarian high grade serous carcinoma: A review on morphological, immunohistochemical and molecular features

High-grade serous ovarian carcinoma (HGSOC) is the most aggressive subtype of epithelial ovarian cancer and a leading cause of mortality among gynecologic malignancies. This review aims to comprehensively analyze the morphological, immunohistochemical, and molecular features of HGSOC, highlighting its pathogenesis and identifying biomarkers with diagnostic, prognostic, and therapeutic significance. Special emphasis is placed on the role of tumor microenvironment (TME) and genomic instability in shaping the tumor's behavior and therapeutic vulnerabilities. Key advancements, such as the identification of TP53 and BRCA mutations, the classification of homologous recombination repair (HRR) deficiencies, and the clinical implications of biomarkers like folate receptor alpha (FRα) and PD-L1 are discussed. These findings reveal actionable insights into targeted therapies, including immune checkpoint inhibitors and PARP inhibitors, which hold promise for improving outcomes in HGSOC. This synthesis of knowledge aims to bridge gaps in understanding HGSOC's multifaceted biology, enhance clinical decision-making, and foster the development of precision therapies.

WTAP contributes to platinum resistance in high-grade serous ovarian cancer by up-regulating malic acid: insights from liquid chromatography and mass spectrometry analysis

High-grade serous cancer (HGSC) is the most prevalent and aggressive subtype of ovarian cancer. In this study, we utilized liquid chromatography and mass spectrometry analysis to investigate metabolic alterations in HGSC. Among the 1353 metabolites identified, 140 were significantly differed between HGSC and normal ovarian tissue. KEGG pathway enrichment analysis revealed 23 distinct metabolic pathways, including the alanine/aspartate/glutamate metabolism, pyruvate metabolism, biosynthesis of amino acids, and citrate cycle, etc. Of the significantly differentiated metabolites, malic acid, fumarate, and phosphoenolpyruvate were found in the citrate cycle and glycolysis. In further analysis, 22 differentially expressed genes (DEGs) of glucose metabolism were found between HGSC and normal controls. Multivariate Cox analysis of the 22 DEGs showed that ME1, ALDOC, and RANBP2 were associated with overall survival in the TCGA cohort.Bioinformatic analysis indicated WTAP is strongly correlated to the expression of ME1, which is a rate-limiting enzyme that regulates the shuttle of malic acid in mitochondria and cytoplasm. After the knockdown of WTAP in A2780 and OVCAR-3 cells, the activity of the malic enzyme decreased which led to the accumulation of malic acid and citric acid, and the reduction of pyruvate and lactic acid. In A2780 and OVCAR-3 cells, the IC50 to platinum was increased after the knockdown of WTAP. After the knockdown of WTAP, the expression of ME1 was down-regulated and the m6A modification was down-regulated in ovarian cell lines. On the SRAMP website, there were two binding sites with high m6A scores at the 5 '-UTR 177 and 970 of ME1 mRNA. WTAP contributes to the platinum resistance through regulating the conversion from aerobic glycolysis to OXPHOS by upregulating the expression of ME1.

A Critical Role of Intracellular PD-L1 in Promoting Ovarian Cancer Progression

Disrupting the interaction between tumor-cell surface PD-L1 and T cell membrane PD-1 can elicit durable clinical responses. However, only about 10% of ovarian cancer patients respond to PD-1/PD-L1 blockade. Here, we show that PD-L1 expression in ovarian cancer-patient tumors is predominantly intracellular. Notably, PARP inhibitor treatment highly increased intracellular PD-L1 accumulation in both ovarian cancer-patient tumor samples and cell lines. We investigated whether intracellular PD-L1 might play a critical role in ovarian cancer progression. Mutating the PD-L1 acetylation site in PEO1 and ID8Brca1-/- ovarian cancer cells significantly decreased PD-L1 levels and impaired colony formation, which was accompanied by cell cycle G2/M arrest and apoptosis induction. PEO1 and ID8Brca1-/- tumors with PD-L1 acetylation site mutation also exhibited significantly reduced growth in mice. Furthermore, targeting intracellular PD-L1 with a cell-penetrating antibody effectively decreased ovarian tumor-cell intracellular PD-L1 level and induced tumor-cell growth arrest and apoptosis, as well as enhanced DNA damage and STING activation, both in vitro and in vivo. In conclusion, we have shown the critical role of intracellular PD-L1 in ovarian cancer progression.

Incorporating immune checkpoint inhibitors in epithelial ovarian cancer

OBJECTIVE

Therapeutic interventions for epithelial ovarian cancer (EOC) have increased greatly over the last decade but improvements outside of biomarker selected therapies have been limited. There remains a pressing need for more effective treatment options that can prolong survival and enhance the quality of life of patients with EOC. In contrast to the significant benefits of immunotherapy with immune checkpoint inhibitors (CPI) seen in many solid tumors, initial experience in EOC suggests limited efficacy of CPIs monotherapy.

METHODS

A systematic review of phase III studies testing the role of CPIs in ovarian cancer was performed.

RESULTS

Seven randomized trials testing CPIs in newly diagnosed (n = 3) and recurrent (n = 4) EOC are evaluated. Overall, those trials included data of 5671 patients. Single-agent PD-L1 inhibitor trials have not shown significant efficacy in newly diagnosed ovarian cancer. Triplet maintenance with bevacizumab plus olaparib and durvalumab is associated with longer progression-free survival than maintenance with bevacizumab alone in patients without tumor BRCA mutations. CPIs were not effective in platinum-sensitive (n = 1031) and platinum-resistant (n = 1420) EOC.

CONCLUSIONS

The value of adding CPI to standard treatment including poly (ADP-ribose) polymerase (PARP) inhibitors with or without bevacizumab remains unclear and is being addressed in ongoing clinical trials. The combination of cytotoxic T-lymphocyte associated protein 4 (CTLA-4) and programmed cell death protein 1 (PD-1) inhibitors may enhance the efficacy of immunotherapy in EOC and studies are underway to investigate the combination of CPI with other emerging treatment modalities. PROSPERO registration ID: CRD42024536017.

Peripheral blood leukocyte signatures as biomarkers in relapsed ovarian cancer patients receiving combined anti-CD73/anti-PD-L1 immunotherapy in arm A of the NSGO-OV-UMB1/ENGOT-OV30 trial

Immune checkpoint inhibitors have demonstrated limited efficacy in overcoming immunosuppression in patients with epithelial ovarian cancer (EOC). Although certain patients experience long-term treatment benefit, reliable biomarkers for responder pre-selection and the distinction of dominant immunosuppressive mechanisms have yet to be identified. Here, we used a 40-marker suspension mass cytometry panel to comprehensively phenotype peripheral blood leukocytes sampled over time from patients with relapsed EOC who underwent combination oleclumab (anti-CD73) and durvalumab (anti-PD-L1) immunotherapy in the NSGO-OV-UMB1/ENGOT-OV30 trial. We found that survival duration was impacted by baseline abundances of total peripheral blood mononuclear cells. Longitudinal analyses revealed a significant increase in CD14+CD16- myeloid cells during treatment, with significant expansion of monocytic myeloid-derived suppressor cells occurring in patients with shorter progression-free survival, who additionally showed a continuous decrease in central memory T-cell abundances. All patients demonstrated significant PD-L1 upregulation over time on most T-cell subsets. Higher CD73 and IDO1 expression on certain leukocytes at baseline significantly positively correlated with longer progression-free survival. Overall, our study proposes potential biomarkers for EOC immunotherapy personalization and response monitoring; however, further validation in larger studies is needed.

Ovarian cancer-derived IL-4 promotes immunotherapy resistance

Ovarian cancer is resistant to immunotherapy, and this is influenced by the immunosuppressed tumor microenvironment (TME) dominated by macrophages. Resistance is also affected by intratumoral heterogeneity, whose development is poorly understood. To identify regulators of ovarian cancer immunity, we employed a spatial functional genomics screen (Perturb-map), focused on receptor/ligands hypothesized to be involved in tumor-macrophage communication. Perturb-map recapitulated tumor heterogeneity and revealed that interleukin-4 (IL-4) promotes resistance to anti-PD-1. We find ovarian cancer cells are the key source of IL-4, which directs the formation of an immunosuppressive TME via macrophage control. IL-4 loss was not compensated by nearby IL-4-expressing clones, revealing short-range regulation of TME composition dictating tumor evolution. Our studies show heterogeneous TMEs can emerge from localized altered expression of cancer-derived cytokines/chemokines that establish immune-rich and immune-excluded neighborhoods, which drive clone selection and immunotherapy resistance. They also demonstrate the potential of targeting IL-4 signaling to enhance ovarian cancer response to immunotherapy.

Integrative multi-omics analysis uncovers tumor-immune-gut axis influencing immunotherapy outcomes in ovarian cancer

Recurrent ovarian cancer patients, especially those resistant to platinum, lack effective curative treatments. To address this, we conducted a phase 2 clinical trial (NCT02853318) combining pembrolizumab with bevacizumab, to increase T cell infiltration into the tumor, and oral cyclophosphamide, to reduce the number of regulatory T cells. The trial accrued 40 heavily pretreated recurrent ovarian cancer patients. The primary endpoint, progression free survival, was extended to a median of 10.2 months. The secondary endpoints demonstrated an objective response rate of 47.5%, and disease control in 30% of patients for over a year while maintaining a good quality of life. We performed comprehensive molecular, immune, microbiome, and metabolic profiling on samples of trial patients. Here, we show increased T and B cell clusters and distinct microbial patterns with amino acid and lipid metabolism are linked to exceptional clinical responses. This study suggests the immune milieu and host-microbiome can be leveraged to improve antitumor response in future immunotherapy trials.

A Narrative Review of the Clinical, Humanistic, and Economic Value of Pembrolizumab-Based Immunotherapy for the Treatment of Breast and Gynecologic Cancers

Breast and gynecologic cancers are common across the world and are associated with substantial societal and economic burden. Pembrolizumab was among the first immune checkpoint inhibitors targeting programmed cell death protein 1 to be approved for the treatment of patients with triple-negative breast cancer, cervical cancer, and endometrial cancer. Recent clinical trials have established pembrolizumab regimens as a standard of care treatment for these tumor types. Clinical data are further supported by patient-reported outcome, cost-effectiveness, and real-world evidence. Pembrolizumab monotherapy and combination regimens do not negatively influence health-related quality of life and are cost-effective relative to comparators. Ongoing phase 3 studies with pembrolizumab will expand the current understanding of its use in breast and gynecologic cancers. Several of these studies are in patients with early-stage disease with the hope of curing patients. The main objective of this review is to summarize the clinical, humanistic, and economic value of pembrolizumab in these settings and to describe the future challenges for patients, caregivers, clinicians, and payers.

Integrated immunogenomic analyses of high-grade serous ovarian cancer reveal vulnerability to combination immunotherapy

Background

The efficacy of immunotherapies in high-grade serous ovarian cancer (HGSOC) is limited, but clinical trials investigating the potential of combination immunotherapy including poly-ADP-ribose polymerase inhibitors (PARPis) are ongoing. Homologous recombination repair deficiency or BRCAness and the composition of the tumor microenvironment appear to play a critical role in determining the therapeutic response.

Methods

We conducted comprehensive immunogenomic analyses of HGSOC using data from several patient cohorts. Machine learning methods were used to develop a classification model for BRCAness from gene expression data. Integrated analysis of bulk and single-cell RNA sequencing data was used to delineate the tumor immune microenvironment and was validated by immunohistochemistry. The impact of PARPi and BRCA1 mutations on the activation of immune-related pathways was studied using ovarian cancer cell lines, RNA sequencing, and immunofluorescence analysis.

Results

We identified a 24-gene signature that predicts BRCAness. Comprehensive immunogenomic analyses across patient cohorts identified samples with BRCAness and high immune infiltration. Further characterization of these samples revealed increased infiltration of immunosuppressive cells, including tumor-associated macrophages expressing TREM2, C1QA, and LILRB4, as specified by single-cell RNA sequencing data and gene expression analysis of samples from patients receiving combination therapy with PARPi and anti-PD-1. Our findings show also that genomic instability and PARPi activated the cGAS-STING signaling pathway in vitro and the downstream innate immune response in a similar manner to HGSOC patients with BRCAness status. Finally, we have developed a web application (https://ovrseq.icbi.at) and an associated R package OvRSeq, which allow for comprehensive characterization of ovarian cancer patient samples and assessment of a vulnerability score that enables stratification of patients to predict response to the combination immunotherapy.

Conclusions

Genomic instability in HGSOC affects the tumor immune environment, and TAMs play a crucial role in modulating the immune response. Based on various datasets, we have developed a diagnostic application that uses RNA sequencing data not only to comprehensively characterize HGSOC but also to predict vulnerability and response to combination immunotherapy.

Immunotherapy for ovarian cancer: towards a tailored immunophenotype-based approach

Despite documented evidence that ovarian cancer cells express immune-checkpoint molecules, such as PD-1 and PD-L1, and of a positive correlation between the presence of tumour-infiltrating lymphocytes and favourable overall survival outcomes in patients with this tumour type, the results of trials testing immune-checkpoint inhibitors (ICIs) in these patients thus far have been disappointing. The lack of response to ICIs can be attributed to tumour heterogeneity as well as inherent or acquired resistance associated with the tumour microenvironment (TME). Understanding tumour immunobiology, discovering biomarkers for patient selection and establishing optimal treatment combinations remains the hope but also a key challenge for the future application of immunotherapy in ovarian cancer. In this Review, we summarize results from trials testing ICIs in patients with ovarian cancer. We propose the implementation of a systematic CD8+ T cell-based immunophenotypic classification of this malignancy, followed by discussions of the preclinical data providing the basis to treat such immunophenotypes with combination immunotherapies. We posit that the integration of an accurate TME immunophenotype characterization with genetic data can enable the design of tailored therapeutic approaches and improve patient recruitment in clinical trials. Lastly, we propose a roadmap incorporating tissue-based profiling to guide future trials testing adoptive cell therapy approaches and assess novel immunotherapy combinations while promoting collaborative research.

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

The 5-year survival rate for ovarian cancer has remained relatively static over the past number of years, which can be attributed in part to the lack of new therapeutic strategies to target this disease. Although numerous other cancer types have benefited from the success of immune checkpoint inhibitors, their use in clinical trials targeting ovarian cancer has shown limited efficacy. Most clinical trials have focused on PD-1/PD-L1 immune checkpoint blockade, either as a monotherapy or in combination with chemotherapies, however inhibiting other pathways may potentially be more efficacious in treating ovarian cancer. For example, drugs targeting some emerging immune checkpoints (such as LAG-3, TIM-3, TIGIT and PVRIG), are entering into clinical trials, which could show improved success for ovarian cancer patients. Similarly, predictive biomarkers that have been approved for use with immune checkpoint inhibitors, such as PD-L1 expression, are limited, as only the presence or absence of PD-L1 is assessed. However, the development of next generation predictive biomarkers, which assesses density and location of tumour infiltrating lymphocytes, could be more beneficial for this heterogenous cancer. In this review we discuss the use of immune checkpoint inhibitors in ovarian cancer, with a focus on high-grade serous disease, and delve into what the future may hold for immunotherapy in this cancer type.

Identification of three subtypes of ovarian cancer and construction of prognostic models based on immune-related genes

BACKGROUND

Immunotherapy has revolutionized the treatment of ovarian cancer (OC), but different immune microenvironments often constrain the efficacy of immunotherapeutic interventions. Therefore, there is an imperative to delineate novel immune subtypes for development of efficacious immunotherapeutic strategies.

METHODS

The immune subtypes of OC were identified by consensus cluster analysis. The differences in clinical features, genetic mutations, mRNA stemness (mRNAsi) and immune microenvironments were analyzed among subtypes. Subsequently, prognostic risk models were constructed based on differentially expressed genes (DEGs) of the immune subtypes using weighted correlation network analysis.

RESULTS

OC patients were classified into three immune subtypes with distinct survival rates and clinical features. Different subtypes exhibited varying tumor mutation burdens, homologous recombination deficiencies, and mRNAsi levels. Significant differences were observed among immune subtypes in terms of immune checkpoint expression and immunogenic cell death. Prognostic risk models were validated as independent prognostic factors demonstrated great predictive performance for survival of OC patients.

CONCLUSION

In this study, three distinct immune subtypes were identified based on gene sets related to vaccine response, with the C2 subtype exhibiting significantly worse prognosis. While no statistically significant differences in tumor mutation burden (TMB) were observed across the three subtypes, the homologous recombination deficiency (HRD) score and mRNA stemness index (mRNAsi) were notably elevated in the C2 group compared to the others. Immune infiltration analysis indicated that the C2 subtype may have an increased presence of regulatory T (Treg) cells, potentially contributing to a more favorable response to combination therapies involving PARP inhibitors and immunotherapy. These findings offer a precision medicine approach for tailoring immunotherapy in ovarian cancer patients. Moreover, the C3 subtype demonstrated significantly lower expression levels of immune checkpoint genes, a pattern validated by independent datasets, and associated with a better prognosis. Further investigation revealed that the immune-related gene FCRL5 correlates with ovarian cancer prognosis, with in vitro experiments showing that it influences the proliferation and migration of the ovarian cancer cell line SKOV3.

Sintilimab combined with bevacizumab in relapsed or persistent ovarian clear cell carcinoma (INOVA): a multicentre, single-arm, phase 2 trial

BACKGROUND

Ovarian clear cell carcinoma rarely responds to second-line chemotherapy, the recommended treatment for relapsed epithelial ovarian cancer. Here, we report the activity and safety of sintilimab in combination with bevacizumab in patients with relapsed or persistent ovarian clear cell carcinoma.

METHODS

In the prospective, multicentre, single-arm, phase 2 INOVA trial, patients aged 18-75 years with histologically confirmed relapsed or persistent ovarian clear cell carcinoma were enrolled from eight tertiary hospitals in China. Eligible patients had an Eastern Cooperative Oncology Group performance status score of 0-2 and previous exposure to at least one cycle of platinum-containing chemotherapy. Enrolled patients received sintilimab (200 mg) and bevacizumab (15 mg/kg) intravenously every 3 weeks until disease progression. The primary endpoint was objective response rate assessed by independent central review based on Response Evaluation Criteria in Solid Tumours version 1.1. Eligible enrolled patients who received at least one cycle of treatment and had at least one tumour response assessment following the baseline assessment per protocol were included in the activity analysis. Patients who received at least one dose of study drug were included in the safety analysis. The study is registered with ClinicalTrials.gov (NCT04735861) and is ongoing.

FINDINGS

Between April 8, 2021, and July 3, 2023, 51 patients were screened and 41 patients received at least one dose of sintilimab in combination with bevacizumab. Response evaluation was completed in 37 patients. Objective responses were observed in 15 patients (objective response rate 40·5%; 95% CI 24·8-57·9), of which five (14%) were complete responses and ten (27%) were partial responses. At data cutoff (Jan 29, 2024), the median follow-up was 16·9 months (IQR 7·5-23·4). Three (7%) patients developed grade 3 treatment-related adverse events including one patient with proteinuria, one patient with myocarditis, and one patient with rash. No treatment-related adverse events of worse than grade 3 severity were recorded. Treatment-related serious adverse events occurred in two (5%) patients including one patient with immune-related myocarditis and another with hypertension and renal dysfunction. No treatment-related deaths occurred.

INTERPRETATION

Sintilimab in combination with bevacizumab showed promising anti-tumour activity and manageable safety in patients with relapsed or persistent ovarian clear cell carcinoma. Larger, randomised trials are warranted to compare this low-toxicity, chemotherapy-free combinatorial regimen with standard chemotherapy.

FUNDING

National Key Technology Research and Development Program of China, National Natural Science Foundation of China, Beijing Xisike Clinical Oncology Research Foundation, and Innovent Biologics.

TRANSLATION

For the Chinese translation of the abstract see Supplementary Materials section.

Novel protein-based prognostic signature linked to immunotherapeutic efficiency in ovarian cancer

BACKGROUND

Personalized medicine remains an unmet need in ovarian cancer due to its heterogeneous nature and complex immune microenvironments, which has gained increasing attention in the era of immunotherapy. A key obstacle is the lack of reliable biomarkers to identify patients who would benefit significantly from the therapy. While conventional clinicopathological factors have exhibited limited efficacy as prognostic indicators in ovarian cancer, multi-omics profiling presents a promising avenue for comprehending the interplay between the tumor and immune components. Here we aimed to leverage the individual proteomic and transcriptomic profiles of ovarian cancer patients to develop an effective protein-based signature capable of prognostication and distinguishing responses to immunotherapy.

METHODS

The workflow was demonstrated based on the Reverse Phase Protein Array (RPPA) and RNA-sequencing profiles of ovarian cancer patients from The Cancer Genome Atlas (TCGA). The algorithm began by clustering patients using immune-related gene sets, which allowed us to identify immune-related proteins of interest. Next, a multi-stage process involving LASSO and Cox regression was employed to distill a prognostic signature encompassing five immune-related proteins. Based on the signature, we subsequently calculated the risk score for each patient and evaluated its prognostic performance by comparing this model with conventional clinicopathological characteristics.

RESULTS

We developed and validated a protein-based prognostic signature in a cohort of 377 ovarian cancer patients. The risk signature outperformed conventional clinicopathological factors, such as age, grade, stage, microsatellite instability (MSI), and homologous recombination deficiency (HRD) status, in terms of prognoses. Patients in the high-risk group had significantly unfavorable overall survival (p < 0.001). Moreover, our signature effectively stratified patients into subgroups with distinct immune landscapes. The high-risk group exhibited higher levels of CD8 T-cell infiltration and a potentially greater proportion of immunotherapy responders. The co-activation of the TGF-β pathway and cancer-associated fibroblasts could impair the ability of cytotoxic T cells to eliminate cancer cells, leading to poor outcomes in the high-risk group.

CONCLUSIONS

The protein-based signature not only aids in evaluating the prognosis but also provides valuable insights into the tumor immune microenvironments in ovarian cancer. Together our findings highlight the importance of a thorough understanding of the immunosuppressive tumor microenvironment in ovarian cancer to guide the development of more effective immunotherapies.

T cell exhaustion and senescence for ovarian cancer immunotherapy

Ovarian cancer is a common gynecological malignancy, and its treatment remains challenging. Although ovarian cancer may respond to immunotherapy because of endogenous immunity at the molecular or T cell level, immunotherapy has so far not had the desired effect. The functional status of preexisting T cells is an indispensable determinant of powerful antitumor immunity and immunotherapy. T cell exhaustion and senescence are two crucial states of T cell dysfunction, which share some overlapping phenotypic and functional features, but each status possesses unique molecular and developmental signatures. It has been widely accepted that exhaustion and senescence of T cells are important strategies for cancer cells to evade immunosurveillance and maintain the immunosuppressive microenvironment. Herein, this review summarizes the phenotypic and functional features of exhaust and senescent T cells, and describes the key drivers of the two T cell dysfunctional states in the tumor microenvironment and their functional roles in ovarian cancer. Furthermore, we present a summary of the molecular machinery and signaling pathways governing T cell exhaustion and senescence. Possible strategies that can prevent and/or reverse T cell dysfunction are also explored. An in-depth understanding of exhausted and senescent T cells will provide novel strategies to enhance immunotherapy of ovarian cancer through redirecting tumor-specific T cells away from a dysfunctional developmental trajectory.

Does an Autoimmune Disorder Following Ovarian Cancer Diagnosis Affect Prognosis?

We investigated whether developing an autoimmune disorder (AID) following a high-grade epithelial ovarian cancer diagnosis improves overall survival. This retrospective study included data from women treated for high-grade serous, endometrioid, or transitional cell ovarian, fallopian tube, or peritoneal cancer FIGO stage III or IV at a Swiss cantonal gynecological cancer center (2008-2023). We used Kaplan-Meier estimates and the Cox proportional hazards model using time-varying covariates for the survival function estimation. In all, 9 of 128 patients developed an AID following a cancer diagnosis. The median time from cancer diagnosis to AID was 2 years (IQR 2-5). These women survived for a median of 3031 days (IQR 1765-3963) versus 972 days (IQR 568-1819) for those who did not develop an AID (p = 0.001). The median overall survival of nine women with a pre-existing AID was 1093 days (IQR 716-1705), similar to those who never had an AID. The multivariate analyses showed older age (p = 0.003, HR 1.04, 95% CI 1.013-1.064) was associated with a poorer prognosis, and developing an AID after a cancer diagnosis was associated with longer survival (p = 0.033, HR 0.113, 95% CI 0.015-0.837). Clinical manifestations of autoimmune disorders following ovarian cancer diagnoses were associated with better overall survival (8 versus 2.7 years), indicating an overactive immune response may improve cancer control.

Tumor targeting peptide TMTP1 modified Antigen capture Nano-vaccine combined with chemotherapy and PD-L1 blockade effectively inhibits growth of ovarian cancer

The mortality of ovarian cancer (OC) has long been the highest among gynecological malignancies. Although OC is considered to be an immunogenic tumor, the effect of immunotherapy is not satisfactory. The immunosuppressive microenvironment is one reason for this, and the absence of recognized effective antigens for vaccines is another. Chemotherapy, as one of the most commonly used treatment for OC, can produce chemotherapy-associated antigens (CAAs) during treatment and show the effect of in situ vaccine. Herein, we designed an antigen capture nano-vaccine NP-TP1@M-M with tumor targeting peptide TMTP1 and dendritic cell (DC) receptor mannose assembled on the surface and adjuvant monophosphoryl lipid A (MPLA) encapsulated in the core of poly (D, L-lactide-co-glycolide) (PLGA) nanoparticles. PLGA itself possessed the ability of antigen capture. TMTP1 was a tumor-homing peptide screened by our research team, which held extensive and excellent tumor targeting ability. After these modifications, NP-TP1@M-M could capture and enrich more tumor-specific antigens after chemotherapy, stimulate DC maturation, activate the adaptive immunity and combined with immune checkpoint blockade to maximize the release of the body's immune potential, providing an eutherapeutic strategy for the treatment of OC.

Neoadjuvant and adjuvant pembrolizumab in advanced high-grade serous carcinoma: the randomized phase II NeoPembrOV clinical trial

This open-label, non-comparative, 2:1 randomized, phase II trial (NCT03275506) in women with stage IIIC/IV high-grade serous carcinoma (HGSC) for whom upfront complete resection was unachievable assessed whether adding pembrolizumab (200 mg every 3 weeks) to standard-of-care carboplatin plus paclitaxel yielded a complete resection rate (CRR) of at least 50%. Postoperatively patients continued assigned treatment for a maximum of 2 years. Postoperative bevacizumab was optional. The primary endpoint was independently assessed CRR at interval debulking surgery. Secondary endpoints were Completeness of Cytoreduction Index (CCI) and peritoneal cancer index (PCI) scores, objective and best response rates, progression-free survival, overall survival, safety, postoperative morbidity, and pathological complete response. The CRR in 61 pembrolizumab-treated patients was 74% (one-sided 95% CI = 63%), exceeding the prespecified ≥50% threshold and meeting the primary objective. The CRR without pembrolizumab was 70% (one-sided 95% CI = 54%). In the remaining patients CCI scores were ≥3 in 27% of the standard-of-care group and 18% of the investigational group and CC1 in 3% of the investigational group. PCI score decreased by a mean of 9.6 in the standard-of-care group and 10.2 in the investigational group. Objective response rates were 60% and 72%, respectively, and best overall response rates were 83% and 90%, respectively. Progression-free survival was similar with the two regimens (median 20.8 versus 19.4 months in the standard-of-care versus investigational arms, respectively) but overall survival favored pembrolizumab-containing therapy (median 35.3 versus 49.8 months, respectively). The most common grade ≥3 adverse events with pembrolizumab-containing therapy were anemia during neoadjuvant therapy and infection/fever postoperatively. Pembrolizumab was discontinued prematurely because of adverse events in 23% of pembrolizumab-treated patients. Combining pembrolizumab with neoadjuvant chemotherapy is feasible for HGSC considered not completely resectable; observed activity in some subgroups justifies further evaluation to improve understanding of the role of immunotherapy in HGSC.

Lenvatinib plus pembrolizumab for patients with previously treated advanced ovarian cancer: Results from the phase 2 multicohort LEAP-005 study

OBJECTIVES

The phase 2, multicohort, open-label LEAP-005 study evaluated lenvatinib plus pembrolizumab in patients with previously treated advanced solid tumors. We report outcomes from the ovarian cancer cohort.

METHODS

Eligible patients had metastatic/unresectable ovarian cancer and had received 3 previous lines of therapy. Patients received lenvatinib 20 mg/day plus pembrolizumab 200 mg every 3 weeks. Treatment continued until progression, unacceptable toxicity, or (for pembrolizumab) completion of 35 cycles. Primary endpoints were objective response rate (ORR) per RECIST version 1.1 and safety. Secondary endpoints included duration of response (DOR), progression-free survival (PFS), and overall survival (OS).

RESULTS

Thirty-one patients were enrolled. 39% had high grade serous ovarian cancer, 23% were platinum-sensitive, 55% were platinum-resistant, 23% were platinum-refractory, and 84% had tumors that had a PD-L1 combined positive (CPS) score ≥1. ORR (95% CI) was 26% (12%-45%) by investigator assessment and 35% (19%-55%) by blinded independent central review (BICR). Per BICR, median DOR was 9.2 (1.5+ to 37.8+) months. ORRs (95% CI) by BICR were 35% (9/26 patients; 17%-56%) for PD-L1 CPS ≥ 1 disease and 50% (2/4 patients; 7%-93%) for PD-L1 CPS < 1 disease. Median (95% CI) PFS by BICR and OS were 6.2 (4.0-8.5) months and 21.3 (11.7-32.3) months, respectively. Treatment-related AEs occurred in 94% of patients (grade 3-4, 77%). One patient died from treatment-related hypovolemic shock.

CONCLUSIONS

Lenvatinib plus pembrolizumab demonstrated antitumor activity as fourth line therapy in patients with advanced ovarian cancer, and no unanticipated safety signals were identified. Responses were observed regardless of PD-L1 status.

New hopes and promises in the treatment of ovarian cancer focusing on targeted treatment-a narrative review

Unfortunately, ovarian cancer is still diagnosed most often only in an advanced stage and is also the most lethal gynecological cancer. Another problem is the fact that treated patients have a high risk of disease recurrence. Moreover, ovarian cancer is very diverse in terms of molecular, histological features and mutations. Many patients may also develop platinum resistance, resulting in poor response to subsequent lines of treatment. To improve the prognosis of patients with ovarian cancer, it is expected to make better existing and implement new, promising treatment methods. Targeted therapies seem very promising. Currently, bevacizumab - a VEGF inhibitor and therapy with olaparib - a polyADP-ribose polymerase inhibitor are approved. Other methods worth considering in the future include: folate receptor α, immune checkpoints or other immunotherapy methods. To improve the treatment of ovarian cancer, it is also important to ameliorate the determination of molecular features to describe and understand which group of patients will benefit most from a given treatment method. This is important because a larger group of patients treated for ovarian cancer can have a greater chance of surviving longer without recurrence.

Prognostic impact of suspicious extraabdominal lymph nodes on patient survival in advanced ovarian cancer

OBJECTIVE

To evaluate the clinical impact of suspicious extra-abdominal lymph nodes (EALNs) identified preoperatively on CT and/or PET/CT images in advanced ovarian cancer.

METHODS

A retrospective study was conducted with 122 patients diagnosed with stage III or IV ovarian cancer with preoperative CT and/or PET/CT images from 2006 to 2022. Imaging studies were evaluated for the presence, size and location of suspicious EALNs. Suspicious lymph node enlargement was defined by a cut-off ≥5mm short-axis dimension on CT and/or lesions with maximum standardized uptake values of ≥2.5 on PET/CT. This study only included patients who did not have their EALNs surgically removed.

RESULTS

A total 109 patients met the inclusion criteria; 36 (33%) had suspicious EALNs and were categorized as "node-positive". The median overall survival (OS) was 45.73 months for the "node-positive" and 46.50 months for the "node-negative" patients (HR 1.17, 95% CI 0.68-2.00, p = 0.579). In multivariate analysis, after adjusting for other variables selected by process of backward elimination using a significance level of p<0.20, suspicious EALNs still showed no clinical significance on OS (aHR 1.20, 95% CI 0.67-2.13, p = 0.537) as well as progression-free survival (aHR 1.43, 95% CI 0.85-2.41, p = 0.174). Old age (aHR 2.23, 95% CI 1.28-3.89, p = 0.005) and platinum resistance (aHR 1.92, 95% CI 1.10-3.36, p = 0.023) affects adversely on OS.

CONCLUSION

Suspicious EALNs did not worsen the prognosis of patients with advanced ovarian cancer. However, its impact on survival is not yet clarified. Further investigation is required to assess the clinical significance of suspicious EALNs on preoperative imaging studies.

The emerging and challenging role of PD-L1 in patients with gynecological cancers: An updating review with clinico-pathological considerations

Over recent years, there has been significant progress in the development of immunotherapeutic molecules designed to block the PD-1/PD-L1 axis. These molecules have demonstrated their ability to enhance the immune response by prompting T cells to identify and suppress neoplastic cells. PD-L1 is a type 1 transmembrane protein ligand expressed on T lymphocytes, B lymphocytes, and antigen-presenting cells and is considered a key inhibitory checkpoint involved in cancer immune regulation. PD-L1 immunohistochemical expression in gynecological malignancies is extremely variable based on tumor stage and molecular subtypes. As a result, a class of monoclonal antibodies targeting the PD-1 receptor and PD-L1, known as immune checkpoint inhibitors, has found successful application in clinical settings. In clinical practice, the standard method for identifying suitable candidates for immune checkpoint inhibitor therapy involves immunohistochemical assessment of PD-L1 expression in neoplastic tissues. The most commonly used PD-L1 assays in clinical trials are SP142, 28-8, 22C3, and SP263, each of which has been rigorously validated on specific platforms. Gynecologic cancers encompass a wide spectrum of malignancies originating from the ovaries, uterus, cervix, and vulva. These neoplasms have shown variable response to immunotherapy which appears to be influenced by genetic and protein expression profiles, including factors such as mismatch repair status, tumor mutational burden, and checkpoint ligand expression. In the present paper, an extensive review of PD-L1 expression in various gynecologic cancer types is discussed, providing a guide for their pathological assessment and reporting.

Phase 1b study of intraperitoneal ipilimumab and nivolumab in patients with recurrent gynecologic malignancies with peritoneal carcinomatosis

BACKGROUND

Intravenous immune checkpoint blockade (ICB) has shown poor response rates in recurrent gynecologic malignancies. Intraperitoneal (i.p.) ICB may result in enhanced T cell activation and anti-tumor immunity.

METHODS

In this phase 1b study, registered at Clinical.

TRIALS

gov (NCT03508570), initial cohorts received i.p. nivolumab monotherapy, and subsequent cohorts received combination i.p. nivolumab every 2 weeks and i.p. ipilimumab every 6 weeks, guided by a Bayesian design. The primary objective was determination of the recommended phase 2 dose (RP2D) of the combination. Secondary outcomes included toxicity, objective response rate (ORR), progression-free survival (PFS), and overall survival (OS).

FINDINGS

The trial enrolled 23 patients: 18 with ovarian cancer, 2 with uterine cancer, and 3 with cervical cancer. Study evaluable patients (n = 16) received a median of 2 prior lines of therapy (range: 1-8). Partial response was observed in 2 patients (12.5%; 1 ovarian, 1 uterine), and complete response was observed in 1 patient (6.3%) with cervical cancer, for an ORR of 18.8% (95% confidence interval: 4.0%-45.6%). The median duration of response was 14.8 months (range: 4.1-20.8), with one complete response ongoing. Median PFS and OS were 2.7 months and not reached, respectively. Grade 3 or higher immune-related adverse events occurred in 2 (8.7%) patients.

CONCLUSIONS

i.p. administration of dual ICB is safe and demonstrated durable responses in a subset of patients with advanced gynecologic malignancy. The RP2D is 3 mg/kg i.p. nivolumab every 2 weeks plus 1 mg/kg ipilimumab every 6 weeks.

FUNDING

This work was funded by Bristol Myers Squibb (CA209-9C7), an MD Anderson Cancer Center Support Grant (CA016672), the Ovarian Cancer Moon Shots Program, the Emerson Collective Fund, and a T32 training grant (CA101642).

Targeting branched N-glycans and fucosylation sensitizes ovarian tumors to immune checkpoint blockade

Aberrant glycosylation is a crucial strategy employed by cancer cells to evade cellular immunity. However, it's unclear whether homologous recombination (HR) status-dependent glycosylation can be therapeutically explored. Here, we show that the inhibition of branched N-glycans sensitizes HR-proficient, but not HR-deficient, epithelial ovarian cancers (EOCs) to immune checkpoint blockade (ICB). In contrast to fucosylation whose inhibition sensitizes EOCs to anti-PD-L1 immunotherapy regardless of HR-status, we observe an enrichment of branched N-glycans on HR-proficient compared to HR-deficient EOCs. Mechanistically, BRCA1/2 transcriptionally promotes the expression of MGAT5, the enzyme responsible for catalyzing branched N-glycans. The branched N-glycans on HR-proficient tumors augment their resistance to anti-PD-L1 by enhancing its binding with PD-1 on CD8+ T cells. In orthotopic, syngeneic EOC models in female mice, inhibiting branched N-glycans using 2-Deoxy-D-glucose sensitizes HR-proficient, but not HR-deficient EOCs, to anti-PD-L1. These findings indicate branched N-glycans as promising therapeutic targets whose inhibition sensitizes HR-proficient EOCs to ICB by overcoming immune evasion.

Durvalumab with or without tremelimumab plus chemotherapy in HRR non-mutated, platinum-resistant ovarian cancer (KGOG 3045): A phase II umbrella trial

AIM

We investigated the efficacy and safety of durvalumab (D) with or without tremelimumab (T) in addition to single-agent chemotherapy (CT) in patients with platinum-resistant recurrent ovarian cancer (PROC) lacking homologous recombination repair (HRR) gene mutations.

PATIENTS AND METHODS

KGOG 3045 was an open-label, investigator-initiated phase II umbrella trial. Patients with PROC without HRR gene mutations who had received ≥2 prior lines of therapy were enrolled. Patients with high PD-L1 expression (TPS ≥25%) were assigned to arm A (D + CT), whereas those with low PD-L1 expression were assigned to arm B (D + T75 + CT). After completing arm B recruitment, patients were sequentially assigned to arms C (D + T300 + CT) and D (D + CT).

RESULTS

Overall, 58 patients were enrolled (5, 18, 17, and 18 patients in arms A, B, C, and D, respectively). The objective response rates were 20.0, 33.3, 29.4, and 22.2%, respectively. Grade 3-4 treatment-related adverse events were observed in 20.0, 66.7, 47.1, and 66.7 of patients, respectively, but were effectively managed. Multivariable analysis demonstrated that adding T to D + CT improved progression-free survival (adjusted HR, 0.435; 95% CI, 0.229-0.824; P = 0.011). Favorable response to chemoimmunotherapy was associated with MUC16 mutation (P = 0.0214), high EPCAM expression (P = 0.020), high matrix remodeling gene signature score (P = 0.017), and low FOXP3 expression (P = 0.047). Patients showing favorable responses to D + T + CT exhibited significantly higher EPCAM expression levels (P = 0.008) and matrix remodeling gene signature scores (P = 0.031) than those receiving D + CT.

CONCLUSIONS

Dual immunotherapy with chemotherapy showed acceptable response rates and tolerable safety in HRR non-mutated PROC, warranting continued clinical investigation.

Carboplatin, paclitaxel, and pembrolizumab followed by pembrolizumab maintenance for primary treatment of incompletely resected epithelial ovarian cancer

Objective

Incompletely resected epithelial ovarian cancer represents a poor prognostic subset of patients. Novel treatment strategies are needed to improve outcomes for this population. We evaluated a treatment strategy combining platinum-based chemotherapy with pembrolizumab followed by pembrolizumab maintenance therapy in the first-line treatment after incomplete resection of epithelial ovarian cancer patients.

Methods

This was a single-arm, non-randomized pilot study of carboplatin, taxane, and immune checkpoint inhibitor, pembrolizumab, followed by 12 months of maintenance pembrolizumab in patients with incompletely resected epithelial ovarian cancer (EOC).

Results

A total of 29 patients were enrolled and evaluated for efficacy and safety. The best response to therapy was complete response in 16 (55%) patients, partial response in 9 (31%) patients, and 3 (10%) patients with progression of disease. The median progression-free survival (PFS) was 13.2 months. Grade 3 and 4 toxicities occurred in 20% of patients. In all, 7 patients discontinued therapy due to adverse events. Quality-of-life scores remained high during therapy. Response to therapy did not correlate with PD-L1 tumor expression.

Conclusions

Combination platinum-taxane therapy with pembrolizumab did not increase median progression-free survival in this cohort of patients.

Key message

EOC is an immunogenic disease, but immune checkpoint inhibitor therapy has yet to impact outcomes. The current study utilized pembrolizumab in combination with standard chemotherapy followed by a maintenance treatment strategy in incompletely resected EOC. Progression-free survival was not extended in this poor prognostic group with combined chemotherapy and immunotherapy.

Clinical trial registration

https://clinicaltrials.gov/, identifier NCT 027766582.

CD47-a novel prognostic predicator in epithelial ovarian cancer and correlations with clinicopathological and gene mutation features

BACKGROUND

Epithelial ovarian cancer (EOC) is insensitive to immunotherapy due to its poor immunogenicity; thus, suitable biomarkers need to be identified for better prognostic stratification and individualized treatment. CD47 is a novel immunotherapy target; however, its impact on EOC prognosis is controversial and correlation with genetic features is unclear. The aim of this study was to investigate the prognostic significance of CD47 and its correlations with biological behaviors and genetic features of EOC.

METHODS

Immunohistochemistry (IHC) and next-generation sequencing (NGS) were performed to examine expressions of CD47, PD-L1, and genomic mutations in the tissue samples of 75 EOC patients. Various clinicopathologic and genomic features were then evaluated to determine their correlation with CD47 expression. Kaplan-Meier analysis and Cox regression analysis were used to identify independent prognostic factors. Risk score modeling was then established, and the predictive capacity of this model was further confirmed by nomogram analysis.

RESULTS

CD47 was mainly expressed in the tumor cell membrane and cytoplasm, and the rate of high CD47 expression was 63.7%. CD47 expression was associated with various clinicopathological factors, including FIGO stage, CA125 and HE4 value, presence of multidisciplinary surgeries, presence and volume of ascites, lymph-node metastasis, Ki-67 index and platinum-resistant, as well as genetic characteristics like BRCA mutation, HRD status, and TP53 mutation in EOC. Patients with high CD47 expression showed worse prognosis than the low-expression group. Cox regression analysis demonstrated that CA125, CD47, and BRCA mutation were independent factors for EOC prognosis. Patients were then categorized into high-risk and low-risk subgroups based on the risk score of the aforementioned independent factors, and the prognosis of the high-risk group was worse than those of the low-risk group. The nomogram showed adequate discrimination with a concordance index of 0.777 (95% CI, 0.732-0.822). The calibration curve showed good consistency.

CONCLUSION

CD47 correlated with various malignant biology and genetic characteristics of EOC and may play pivotal and multifaceted roles in the tumor microenvironment of EOC Finally, we constructed a reliable prediction model centered on CD47 and integrated CA125 and BRCA to better guide high-risk population management.

Phase 1/2 trial of avelumab combined with utomilumab (4-1BB agonist), PF-04518600 (OX40 agonist), or radiotherapy in patients with advanced gynecologic malignancies

BACKGROUND

Immune checkpoint blockade has shown mixed results in advanced/recurrent gynecologic malignancies. Efficacy may be improved through costimulation with OX40 and 4-1BB agonists. The authors sought to evaluate the safety and efficacy of avelumab combined with utomilumab (a 4-1BB agonist), PF-04518600 (an OX40 agonist), and radiotherapy in patients with recurrent gynecologic malignancies.

METHODS

The primary end point in this six-arm, phase 1/2 trial was safety of the combination regimens. Secondary end points included the objective response rate (ORR) according to Response Evaluation Criteria in Solid Tumors and immune-related Response Evaluation Criteria in Solid Tumors, the disease control rate (DCR), the duration of response, progression-free survival, and overall survival.

RESULTS

Forty patients were included (35% with cervical cancer, 30% with endometrial cancer, and 35% with ovarian cancer). Most patients (n = 33; 83%) were enrolled in arms A-C (no radiation). Among 35 patients who were evaluable for efficacy, the ORR was 2.9%, and the DCR was 37.1%, with a median duration of stable disease of 5.4 months (interquartile range, 4.1-7.3 months). Patients with cervical cancer in arm A (avelumab and utomilumab; n = 9 evaluable patients) achieved an ORR of 11% and a DCR of 78%. The median progression-free survival was 2.1 months (95% CI, 1.8-3.5 months), and overall survival was 9.4 months (95% CI, 5.6-11.9 months). No dose-limiting toxicities or grade 3-5 immune-related adverse events were observed.

CONCLUSIONS

The findings from this trial highlight that, in heavily pretreated patients with gynecologic cancer, even multidrug regimens targeting multiple immunologic pathways, although safe, did not produce significant responses. A DCR of 78% in patients with cervical cancer who received avelumab and utomilumab indicates that further research on this combination in select patients may be warranted.

Efficacy and safety of neoadjuvant chemotherapy containing anti-angiogenic drugs, immunotherapy, or PARP inhibitors for ovarian cancer

Ovarian cancer is the most lethal gynecologic malignancy. The standard treatment involves chemotherapy with platinum-paclitaxel following cytoreductive surgery. For patients battling widespread and aggressive tumor spread, neoadjuvant chemotherapy (NACT) followed by interval debulking surgery emerges as an encouraging alternative. However, the effectiveness of this strategy is often limited by advanced-stage diagnosis and high likelihood of recurrence. The high mortality rate necessitates the exploration of targeted therapies. Present results signal promising efficacy and acceptable toxicities of anti-angiogenic drugs, immunotherapy, or PARP inhibitors used in chemotherapy. However, the potential integration of these drugs into NACT raises questions about response rates, surgical outcomes, and adverse events. This review delves into the findings from all published articles and ongoing studies, aiming to summarize the clinical use of anti-angiogenic drugs, immunotherapy, or PARP inhibitors in NACT, highlight the positive and negative aspects, and outline future perspectives.

Improved overall survival in patients with high-grade serous ovarian cancer is associated with CD16a+ immunologic neighborhoods containing NK cells, T cells and macrophages

Background

For patients with high grade serous carcinoma of the ovary (HGSC), survival rates have remained static for the last half century. Despite the presence of tumor mutations and infiltration of immune cells, existing immunotherapies have achieved little success against HGSC. These observations highlight a gap in the understanding of how the immune system functions and interacts within HGSC tumors.

Methods

We analyzed duplicate core samples from 939 patients with HGSC to understand patterns of immune cell infiltration, localization, and associations with clinical features. We used high-parameter immunohistochemical/Opal multiplex, digital pathology, computational biology, and multivariate analysis to identify immune cell subsets and their associations with HGSC tumors.

Results

We defined six patterns of cellular infiltration by spatially restricted unsupervised clustering of cell subsets. Each pattern was represented to some extent in most patient samples, but their specific distributions differed. Overall (OS) and progression-free survival (PFS) corresponded with higher infiltration of CD16a+ cells, and their co-localization with macrophages, T cells, NK cells, in one of six cellular neighborhoods that we defined with our spatial assessment.

Conclusions

Immune cell neighborhoods containing CD16a+ cells are associated with improved OS and PFS for patients with HGSC. Patterns of immunologic neighborhoods differentiate patient outcomes, and could inform future, more precise approaches to treatment.

CX3CR1 is a potential biomarker of immune microenvironment and prognosis in epithelial ovarian cancer

Immunotherapy is less efficient for epithelial ovarian cancer and lacks ideal biomarkers to select the best beneficiaries for immunotherapy. CX3CR1 as chemokine receptor mainly expressed on immune cell membranes, and combined with its unique ligand CX3CL1, mediates tissue chemotaxis and adhesion of immune cells. However, the immune functional and prognostic value of CX3CR1 in epithelial ovarian cancer has not been clarified. A comprehensive retrospective analysis was performed by using the online database to identify the underlying immunological mechanisms and prognostic value of CX3CR1. The Human Protein Atlas, gene expression profiling interactive analysis, and TISIDB (an integrated repository portal for tumor-immune system interactions) database showed that CX3CR1 expressed higher in epithelial ovarian cancer than that in normal ovarian tissue. Four hundred twenty-two cases from Gene Expression Profiling Interactive Analysis and 1656 cases from Kaplan-Meier plotter database showed higher expression of CX3CR1 (above median) was associated with unfavorable overall survival. TIMER, UALCAN, and TISIDB database were applied to validate CX3CR1 negative impact on overall survival. In addition, correlation analysis showed that the expression level of CX3CR1 was positive association with infiltrating levels of B cells (R = 0.31, P = 3.10e-12), CD8+ T cells (R = 0.26, P = 7.93e-09), CD4+ T cells (R = 0.11, P = 1.41e-02), macrophages (R = 0.32, P = 4.29e-13), dendritic cells (R = 0.27, P = 2.98e-09), and neutrophil (R = 0.25, P = 3.25e-08) in epithelial ovarian cancer. Therefore, CX3CR1 involved in reshaping the immune microenvironment for epithelial ovarian cancer and maybe a potential immunotherapy target and prognostic marker for ovarian cancer.

Immune checkpoints as potential theragnostic biomarkers for epithelial ovarian cancer

BACKGROUND

Epithelial ovarian cancer (EOC) is the leading cause of death associated with gynecologic tumors. EOC is asymptomatic in early stages, so most patients are not diagnosed until late stages, highlighting the need to develop new diagnostic biomarkers. Mediators of the tumoral microenvironment may influence EOC progression and resistance to treatment.

AIM

To analyze immune checkpoints to evaluate them as theranostic biomarkers for EOC.

PATIENTS AND METHODS

Serum levels of 16 immune checkpoints were determined in EOC patients and healthy controls using the MILLIPLEX MAP® Human Immuno-Oncology Checkpoint Protein Magnetic Bead Panel.

RESULTS

Seven receptors: BTLA, CD40, CD80/B7-1, GITRL, LAG-3, TIM-3, TLR-2 are differentially expressed between EOC and healthy controls. Serum levels of immune checkpoints in EOC patients are positively significantly correlated with levels of their ligands, with a higher significant correlation between CD80 and CTLA4 than between CD28 and CD80. Four receptors, CD40, HVEM, PD-1, and PD-L1, are positively associated with the development of resistance to Taxol-platinum-based chemotherapy. All of them have an acceptable area under the curve (>0.7).

CONCLUSION

This study has yielded a first panel of seven immune checkpoints (BTLA, CD40, CD80/B7-1, GITRL, LAG-3, TIM-3, TLR-2) associated with a higher risk of EOC and a second panel of four immune checkpoints (CD40, HVEM, PD-1, PD-L1) that may help physicians to identify EOC patients who are at high risk of developing resistance to EOC chemotherapy.

Targeting CD24 as a novel immunotherapy for solid cancers

Cluster of differentiation 24 (CD24), a mucin-like highly glycosylated molecule has been extensively studied as a cancer stem cell marker in a variety of solid cancers. The functional role of CD24 is either fulfilled by combining with ligands or participating in signal transduction, which mediate the initiation and progression of neoplasms. Recently, CD24 was also described as an innate immune checkpoint with apparent significance in several types of solid cancers. Herein, we review the current understanding of the molecular fundamentals of CD24, the role of CD24 in tumorigenesis and cancer progression, the possibility as a promising therapeutic target and summarized different therapeutic agents or strategies targeting CD24 in solid cancers. Video Abstract.

Molecular determinants of clinical outcomes of pembrolizumab in recurrent ovarian cancer: Exploratory analysis of KEYNOTE-100

OBJECTIVE

This prespecified exploratory analysis evaluated the association of gene expression signatures, tumor mutational burden (TMB), and multiplex immunohistochemistry (mIHC) tumor microenvironment-associated cell phenotypes with clinical outcomes of pembrolizumab in advanced recurrent ovarian cancer (ROC) from the phase II KEYNOTE-100 study.

METHODS

Pembrolizumab-treated patients with evaluable RNA-sequencing (n = 317), whole exome sequencing (n = 293), or select mIHC (n = 125) data were evaluated. The association between outcomes (objective response rate [ORR], progression-free survival [PFS], and overall survival [OS]) and gene expression signatures (T-cell-inflamed gene expression profile [TcellinfGEP] and 10 non-TcellinfGEP signatures), TMB, and prespecified mIHC cell phenotype densities as continuous variables was evaluated using logistic (ORR) and Cox proportional hazards regression (PFS; OS). One-sided p-values were calculated at prespecified α = 0.05 for TcellinfGEP, TMB, and mIHC cell phenotypes and at α = 0.10 for non-TcellinfGEP signatures; all but TcellinfGEP and TMB were adjusted for multiplicity.

RESULTS

No evidence of associations between ORR and key axes of gene expression was observed. Negative associations were observed between outcomes and TcellinfGEP-adjusted glycolysis (PFS, adjusted-p = 0.019; OS, adjusted-p = 0.085) and hypoxia (PFS, adjusted-p = 0.064) signatures. TMB as a continuous variable was not associated with outcomes (p > 0.05). Positive associations were observed between densities of myeloid cell phenotypes CD11c+ and CD11c+/MHCII-/CD163-/CD68- in the tumor compartment and ORR (adjusted-p = 0.025 and 0.013, respectively).

CONCLUSIONS

This exploratory analysis in advanced ROC did not find evidence for associations between gene expression signatures and outcomes of pembrolizumab. mIHC analysis suggests CD11c+ and CD11c+/MHCII-/CD163-/CD68- phenotypes representing myeloid cell populations may be associated with improved outcomes with pembrolizumab in advanced ROC.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, NCT02674061.

The Landscape of Adoptive Cellular Therapies in Ovarian Cancer

Ovarian cancers are typically poorly immunogenic and have demonstrated disappointing responses to immune checkpoint inhibitor (ICI) therapy. Adoptive cellular therapy (ACT) offers an alternative method of harnessing the immune system that has shown promise, especially with the success of chimeric antigen receptor T-cell (CAR-T) therapy in haematologic malignancies. So far, ACT has led to modest results in the treatment of solid organ malignancies. This review explores the possibility of ACT as an effective alternative or additional treatment to current standards of care in ovarian cancer. We will highlight the potential of ACTs, such as CAR-T, T-cell receptor therapy (TCR-T), tumour-infiltrating lymphocytes (TILs) and cell-based vaccines, whilst also discussing their challenges. We will present clinical studies for these approaches in the treatment of immunologically 'cold' ovarian cancer and consider the rationale for future research.

New insights for gynecological cancer therapies: from molecular mechanisms and clinical evidence to future directions

Advanced and recurrent gynecological cancers lack effective treatment and have poor prognosis. Besides, there is urgent need for conservative treatment for fertility protection of young patients. Therefore, continued efforts are needed to further define underlying therapeutic targets and explore novel targeted strategies. Considerable advancements have been made with new insights into molecular mechanisms on cancer progression and breakthroughs in novel treatment strategies. Herein, we review the research that holds unique novelty and potential translational power to alter the current landscape of gynecological cancers and improve effective treatments. We outline the advent of promising therapies with their targeted biomolecules, including hormone receptor-targeted agents, inhibitors targeting epigenetic regulators, antiangiogenic agents, inhibitors of abnormal signaling pathways, poly (ADP-ribose) polymerase (PARP) inhibitors, agents targeting immune-suppressive regulators, and repurposed existing drugs. We particularly highlight clinical evidence and trace the ongoing clinical trials to investigate the translational value. Taken together, we conduct a thorough review on emerging agents for gynecological cancer treatment and further discuss their potential challenges and future opportunities.

Exploring the tumor immune microenvironment in ovarian cancer: a way-out to the therapeutic roadmap

INTRODUCTION

Despite cancer treatment strides, mortality due to ovarian cancer remains high globally. While immunotherapy has proven effective in treating cancers with low cure rates, it has limitations. Growing evidence suggests that both tumoral and non-tumoral components of the tumor immune microenvironment (TIME) play a significant role in cancer growth. Therefore, developing novel and focused therapy for ovarian cancer is critical. Studies indicate that TIME is involved in developing ovarian cancer, particularly genome-, transcriptome-, and proteome-wide studies. As a result, TIME may present a prospective therapeutic target for ovarian cancer patients.

AREAS COVERED

We examined several TIME-targeting medicines and the connection between TIME and ovarian cancer. The key protagonists and events in the TIME and therapeutic strategies that explicitly target these events in ovarian cancer are discussed.

EXPERT OPINION

We highlighted various targeted therapies against TIME in ovarian cancer, including anti-angiogenesis therapies and immune checkpoint inhibitors. While these therapies are in their infancy, they have shown promise in controlling ovarian cancer progression. The use of 'omics' technology is helping in better understanding of TIME in ovarian cancer and potentially identifying new therapeutic targets. TIME-targeted strategies could account for an additional treatment strategy when treating ovarian cancer.

Identification of antigenic epitopes recognized by tumor infiltrating lymphocytes in high grade serous ovarian cancer by multi-omics profiling of the auto-antigen repertoire

Immunotherapeutic strategies aimed at enhancing tumor cell killing by tumor-specific T cells hold great potential for reducing tumor burden and prolonging survival of cancer patients. Although many potential tumor antigens have been described, identifying relevant targets when designing anti-cancer vaccines or targeted cell therapies remains a challenge. To identify novel, potentially immunogenic candidate tumor antigens, we performed integrated tumor transcriptomic, seromic, and proteomic analyses of high grade serous ovarian cancer (HGSC) patient tumor samples. We identified tumor neo-antigens and over-expressed antigens using whole exome and RNA sequencing and examined these in relation to patient-matched auto-antibody repertoires. Focusing on MHC class I epitopes recognized by CD8+ T cells, HLA-binding epitopes were identified or predicted from the highly expressed, mutated, or auto-antibody target antigen, or MHC-associated peptides (MAPs). Recognition of candidate antigenic peptides was assessed within the tumor-infiltrating T lymphocyte (TIL) population expanded from each patient. Known tumor-associated antigens (TAA) and cancer/testis antigens (CTA) were commonly found in the auto-antibody and MAP repertoires and CD8+ TILs recognizing epitopes from these antigens were detected, although neither expression level nor the presence of auto-antibodies correlated with TIL recognition. Auto-antibodies against tumor-mutated antigens were found in most patients, however, no TIL recognition of the highest predicted affinity neo-epitopes was detected. Using high expression level, auto-antibody recognition, and epitope prediction algorithms, we identified epitopes in 5 novel antigens (MOB1A, SOCS3, TUBB, PRKAR1A, CCDC6) recognized by HGSC patient TILs. Furthermore, selection of epitopes from the MAP repertoire identified 5 additional targets commonly recognized by multiple patient TILs. We find that the repertoire of TIL specificities includes recognition of highly expressed and immunogenic self-antigens that are processed and presented by tumors. These results indicate an ongoing autoimmune response against a range of self-antigens targeted by HGSC TILs.

Chasing Immune Checkpoint Inhibitors in Ovarian Cancer: Novel Combinations and Biomarker Discovery

A deep understanding of the tumor microenvironment and the recognition of tumor-infiltrating lymphocytes as a prognostic factor have resulted in major milestones in immunotherapy that have led to therapeutic advances in treating many cancers. Yet, the translation of this knowledge to clinical success for ovarian cancer remains a challenge. The efficacy of immune checkpoint inhibitors as single agents or combined with chemotherapy has been unsatisfactory, leading to the exploration of alternative combination strategies with targeted agents (e.g., poly-ADP-ribose inhibitors (PARP)and angiogenesis inhibitors) and novel immunotherapy approaches. Among the different histological subtypes, clear cell ovarian cancer has shown a higher sensitivity to immunotherapy. A deeper understanding of the mechanism of immune resistance within the context of ovarian cancer and the identification of predictive biomarkers remain central discovery benchmarks to be realized. This will be critical to successfully define the precision use of immune checkpoint inhibitors for the treatment of ovarian cancer.

Implementation of Nurse Navigation Improves Rate of Molecular Tumor Testing for Ovarian Cancer in a Gynecologic Oncology Practice

PURPOSE

The purpose of this study was to assess the impact of implementing a Nurse Navigator (NN) to improve the rate and timeliness of molecular tumor testing.

METHODS

This is an evaluation of the impact of education sessions, consensus building, and NN implementation for molecular tumor testing in patients with epithelial ovarian cancer. The NNs' responsibilities included attending tumor boards and ensuring Next Generation Sequencing (NGS) is ordered, reviewed, and coordinated for appropriate patients.

RESULTS

NNs significantly improved NGS testing rates from 35.29% to 77.27%, p = 0.002. Ordering a targeted panel test (TPT) was the most common reason for not ordering NGS in the pre-NN cohort (13/22, 59%). The total turnaround time for testing was reduced after the introduction of NNs from 145.2 days to 42.8 days, p < 0.0001. The post-NN group had a significantly higher rate of actionable mutations identified for the recurrent setting [67.6% versus 20.8% (p = 0.0005)] and a trend towards a higher rate of actionable mutations identified in the frontline setting [41.2% versus 33.3% (p = 0.41)].

CONCLUSION

NNs significantly improved somatic tumor testing rates and timeliness for patients with ovarian cancer. Discontinuing TPT in favor of NGS revealed a higher rate of actionable tumor mutations that would have been missed with TPT alone.

Immune checkpoint inhibitors in ovarian cancer: where do we go from here?

Epithelial ovarian cancer (EOC) is the most lethal gynaecological malignancy, and despite advancements in therapeutics, most women unfortunately still succumb to their disease. Immunotherapies, in particular immune checkpoint inhibitors (ICI), have been therapeutically transformative in many tumour types, including gynaecological malignancies such as cervical and endometrial cancer. Unfortunately, these therapeutic successes have not been mirrored in ovarian cancer clinical studies. This review provides an overview of the ovarian tumour microenvironment (TME), particularly factors associated with survival, and explores current research into immunotherapeutic strategies in EOC, with an exploratory focus on novel therapeutics in navigating drug resistance.

PD-1/PD-L1 immune checkpoint blockade in ovarian cancer: dilemmas and opportunities

Immune checkpoint inhibitors (ICIs) have revolutionized treatment in oncology. Antibodies against PD-1/PD-L1 and ICI-based combinations are under clinical investigations in multiple cancers, including ovarian cancer. However, the success of ICIs has not materialized in ovarian cancer, which remains one of the few malignancies where ICIs exhibit modest efficacy as either monotherapy or combination therapy. In this review, we summarize completed and ongoing clinical trials of PD-1/PD-L1 blockade in ovarian cancer, categorize the underlying mechanisms of resistance emergence, and introduce candidate approaches to rewire the tumor microenvironment (TME) to potentiate anti-PD-1/PD-L1 antibodies. Teaser: The intrinsic resistance of ovarian cancer to PD-1/PD-L1 blockade could be overcome by advanced understanding of underlying mechanisms and discoveries of new actionable targets for combinatory treatment.

Tumor metabolism rewiring in epithelial ovarian cancer

The mortality rate of epithelial ovarian cancer (EOC) remains the first in malignant tumors of the female reproductive system. The characteristics of rapid proliferation, extensive implanted metastasis, and treatment resistance of cancer cells require an extensive metabolism rewiring during the progression of cancer development. EOC cells satisfy their rapid proliferation through the rewiring of perception, uptake, utilization, and regulation of glucose, lipids, and amino acids. Further, complete implanted metastasis by acquiring a superior advantage in microenvironment nutrients competing. Lastly, success evolves under the treatment stress of chemotherapy and targets therapy. Understanding the above metabolic characteristics of EOCs helps to find new methods of its treatment.

Mass Spectrometry-based Proteomics of Epithelial Ovarian Cancers: a Clinical Perspective

Increasing proteomic studies focused on epithelial ovarian cancer (EOC) have attempted to identify early disease biomarkers, establish molecular stratification, and discover novel druggable targets. Here we review these recent studies from a clinical perspective. Multiple blood proteins have been used clinically as diagnostic markers. The ROMA test integrates CA125 and HE4, while the OVA1 and OVA2 tests analyze multiple proteins identified by proteomics. Targeted proteomics has been widely used to identify and validate potential diagnostic biomarkers in EOCs, but none has yet been approved for clinical adoption. Discovery proteomic characterization of bulk EOC tissue specimens has uncovered a large number of dysregulated proteins, proposed new stratification schemes, and revealed novel targets of therapeutic potential. A major hurdle facing clinical translation of these stratification schemes based on bulk proteomic profiling is intra-tumor heterogeneity, namely that single tumor specimens may harbor molecular features of multiple subtypes. We reviewed over 2500 interventional clinical trials of ovarian cancers since 1990, and cataloged 22 types of interventions adopted in these trials. Among 1418 clinical trials which have been completed or are not recruiting new patients, about 50% investigated chemotherapies. Thirty-seven clinical trials are at phase 3 or 4, of which 12 focus on PARP, 10 on VEGFR, 9 on conventional anti-cancer agents, and the remaining on sex hormones, MEK1/2, PD-L1, ERBB, and FRα. Although none of the foregoing therapeutic targets were discovered by proteomics, newer targets discovered by proteomics, including HSP90 and cancer/testis antigens, are being tested also in clinical trials. To accelerate the translation of proteomic findings to clinical practice, future studies need to be designed and executed to the stringent standards of practice-changing clinical trials. We anticipate that the rapidly evolving technology of spatial and single-cell proteomics will deconvolute the intra-tumor heterogeneity of EOCs, further facilitating their precise stratification and superior treatment outcomes.

PD-L1 and MHC Class I Expression in High-grade Ovarian Cancers, Including Platinum-resistant Recurrences Treated With Checkpoint Inhibitor Therapy

Immune-modulating therapies targeting the programmed cell death-1/programmed cell death ligand-1 (PD-L1) immunosuppressive system have been used successfully in many solid tumor types. There is evidence that biomarkers such as PD-L1 and major histocompatibility complex (MHC) class I help identify candidates for anti-programmed cell death-1/PD-L1 checkpoint inhibition, though the evidence is limited in ovarian malignancies. PD-L1 and MHC Class I immunostaining was performed on pretreatment whole tissue sections in 30 cases of high-grade ovarian carcinoma. The PD-L1 combined positive score was calculated (a score of ≥1 is considered positive). MHC class I status was categorized as an intact or subclonal loss. In patients who received immunotherapy, drug response was assessed using RECIST criteria. PD-L1 was positive in 26 of 30 cases (87%; combined positive score: 1 to 100). Seven of 30 patients showed subclonal loss of MHC class I (23%), and this occurred in both PD-L1 negative (3/4; 75%) and PD-L1 positive (4/26; 15%) cases. Only 1 of 17 patients who received immunotherapy in the setting of a platinum-resistant recurrence responded to the addition of immunotherapy, and all 17 died of disease. In the setting of recurrent disease, patients did not respond to immunotherapy regardless of PD-L1/MHC class I status, suggesting that these immunostains may not be effective predictive biomarkers in this setting. Subclonal loss of expression of MHC class I occurs in ovarian carcinoma, including in PD-L1 positive cases, suggesting that the 2 pathways of immune evasion may not be mutually exclusive and that it may be important to interrogate MHC class I status in PD-L1 positive tumors to identify additional immune evasion mechanisms in these tumors.

Cancer Treatment-Related Cardiovascular Toxicity in Gynecologic Malignancies: JACC: CardioOncology State-of-the-Art Review

Improvements in early detection and treatment of gynecologic malignancies have led to an increasing number of survivors who are at risk of long-term cardiac complications from cancer treatment. Multimodality therapies for gynecologic malignancies, including conventional chemotherapy, targeted therapeutics, and hormonal agents, place patients at risk of cancer therapy-related cardiovascular toxicity during and following treatment. Although the cardiotoxicity associated with some female predominant cancers (eg, breast cancer) have been well recognized, there has been less recognition of the potential adverse cardiovascular effects of anticancer therapies used to treat gynecologic malignancies. In this review, the authors provide a comprehensive overview of the cancer therapeutic agents used in gynecologic malignancies, associated cardiovascular toxicities, risk factors for cardiotoxicity, cardiac imaging, and prevention strategies.

Neutrophil Extracellular Traps and Cancer: Trapping Our Attention with Their Involvement in Ovarian Cancer

Neutrophils, the most abundant circulating leukocytes, play a well-known role in defense against pathogens through phagocytosis and degranulation. However, a new mechanism involving the release of neutrophil extracellular traps (NETs) composed of DNA, histones, calprotectin, myeloperoxidase, and elastase, among others, has been described. The so-called NETosis process can occur through three different mechanisms: suicidal, vital, and mitochondrial NETosis. Apart from their role in immune defense, neutrophils and NETs have been involved in physiopathological conditions, highlighting immunothrombosis and cancer. Notably, neutrophils can either promote or inhibit tumor growth in the tumor microenvironment depending on cytokine signaling and epigenetic modifications. Several neutrophils' pro-tumor strategies involving NETs have been documented, including pre-metastatic niche formation, increased survival, inhibition of the immune response, and resistance to oncologic therapies. In this review, we focus on ovarian cancer (OC), which remains the second most incidental but the most lethal gynecologic malignancy, partly due to the presence of metastasis, often omental, at diagnosis and the resistance to treatment. We deepen the state-of-the-art on the participation of NETs in OC metastasis establishment and progression and their involvement in resistance to chemo-, immuno-, and radiotherapies. Finally, we review the current literature on NETs in OC as diagnostic and/or prognostic markers, and their contribution to disease progression at early and advanced stages. The panoramic view provided in this article might pave the way for enhanced diagnostic and therapeutic strategies to improve the prognosis of cancer patients and, specifically, OC patients.

Efficacy and safety of PD-1/PD-L1 inhibitors in the treatment of recurrent and refractory ovarian cancer: A systematic review and a meta-analysis

Objective: To explore the efficacy and safety of PD-1/PD-L1 inhibitors in treating recurrent/refractory ovarian cancer (OC).

Methods: The online databases, including PubMed, Embase and Cochrane Library, were searched for relevant literatures on exploring the efficacy and safety of PD-1/PD-L1 inhibitors in the treatment of recurrent/refractory OC. The keywords are as follows: Ovarian neoplasms, programmed death receptor, PD-1, PD-L1, immunotherapy, and immune checkpoint inhibitor. Furthermore, qualified studies were screened for further meta-analysis.

Results: In this study, 11 studies (990 patients) were analyzed to evaluate the efficacy of PD-1/PD-L1 inhibitors in the treatment of recurrent/refractory OC. The combined results proved that the objective response rate (ORR) was 6.7%, 95% CI (4.6%,9.2%), disease control rate (DCR) was 37.9%, 95% CI (33.0%, 42.8%), median overall survival (OS) was 10.70 months, 95% CI (9.23, 12.17), and median progression free survival (PFS) was 2.24 months, 95% CI (2.05, 2.43). In addition, in terms of the safety of patients suffering from recurrent/refractory OC and receiving PD-1/PD-L1 inhibitors, the combined treatment related adverse events (TRAEs) were 70.9% (61.7%–80.2%), and the combined immune related adverse events (iAEs) were 29%, 95% CI (14.7%, 43.3%).

Conclusion: In patients with recurrent/refractory OC, PD-1/PD-L1 inhibitors were used alone and there was no obvious evidence of improved efficacy and survival. As for safety, the incidences of TRAEs and iAEs are high, so PD1/PD-L1 inhibitors should be applied according to individual conditions.

Clinical Trial Registration:https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=367525, identifier CRD42022367525.