Immunotherapy for Ovarian Cancer: Disappointing or Promising?

Ovarian cancer, one of the deadliest malignancies, lacks effective treatment, despite advancements in surgical techniques and chemotherapy. Thus, new therapeutic approaches are imperative to improving treatment outcomes. Immunotherapy, which has demonstrated considerable success in managing various cancers, has already found its place in clinical practice. This review aims to provide an overview of ovarian tumor immunotherapy, including its basics, key strategies, and clinical research data supporting its potential. In particular, this discussion highlights promising strategies such as checkpoint inhibitors, vaccines, and pericyte transfer, both individually and in combination. However, the advancement of new immunotherapies necessitates large controlled randomized trials, which will undoubtedly shape the future of ovarian cancer treatment.

Risk stratification and molecular heterogeneity of endometrial cancer and expression profile of TIM-3: A retrospective cohort study.

OBJECTIVE: The present study aimed to implement ProMisE classification and risk grouping on a retrospective cohort of 628 patients with endometrial cancer (EC) and determine the molecular heterogeneity across subtypes and subgroups, as well as to investigate the potential beneficiary for TIM-3 checkpoint inhibition in ECs. METHODS: Protein expressions of p53, MMR, TIM-3 and CD8 were measured by immunohistochemistry, and massively parallel sequencing was conducted for 128 cancer-related genes. Patients were categorized into four ProMisE subtypes: MMR-deficient (MMRd), POLE-ultramutated (POLEmut), p53-wild type (p53wt), and p53-abnormal (p53abn), and were subjected to risk classification. RESULTS: 43 (6.9%) patients belonged to POLEmut, 118 (18.8%) to MMRd, 69 (11%) to p53abn, and 398 (63.3%) to p53wt. Compared to the 2016 stratification system, the 2021 ESGO/ESTRO/ESP risk stratification integrated with molecular classification revealed that 11 patients (11/628, 1.8%) were upgraded due to the p53abn signature, whereas 23 patients (23/628, 3.7%) were downgraded due to the POLEmut signature. JAK1 and RAD50 mutations showed higher frequencies in patients with aggressive phenotypes. RAD51B mutation was significantly related to poor RFS of the p53wt subtype but not of the other three molecular subgroups. TIM-3 expression was detected in 30.9% immune cells (ICs) and 29.0% tumor cells (TCs) in ECs, respectively. It was frequently expressed in POLEmut and MMRd ECs as compared to that in the other two molecular subtypes in TCs and ICs. CONCLUSIONS: Our study revealed the molecular heterogeneity across subtypes and subgroups. The new risk stratification system changed the risk grouping of some patients due to the integration of molecular features. RAD51B mutation can further stratify the recurrence risk in the p53wt subtype. Patients with MMRd or POLEmut may benefit most from immunotherapy against TIM-3.

MiR-29c downregulates tumor-expressed B7-H3 to mediate the antitumor NK-cell functions in ovarian cancer.

OBJECTIVE: B7-H3 is a member of the B7 family of immune checkpoint molecule. Although B7-H3 has been shown to regulate T cell-mediated peripheral immune response, whether it also correlated with NK cell exhaustion in ovarian cancer remains unclear. The purpose of this study was to explore the mechanism of B7-H3 regulating NK-cell proliferation and function. MATERIAL AND METHODS: To investigate the relationship between B7-H3 expression and the NK-cell function in ovarian cancer, human ovarian tumor tissues and cell lines were first examined the protein and mRNA expression of B7-H3 by quantitative real-time PCR (qRT-PCR), Immunohistochemistry and Western-blot assays. Then we established B7-H3 knockout cell lines and measured the cytotoxicity of NK cells on these cells by LDH release assay and Flow Cytometry. In addition, we analyzed B7-H3 in the regulation of glycolysis and glycolysis-related proteins by Glycolysis Stress Test, Glucose Consumption Assay and Western-blot. Moreover, luciferase reporter assay was used to confirm the directly regulation of miR-29c to B7-H3. Finally, we carried out in vivo experiments. RESULTS: We observed that tumor-expressed B7-H3 inhibits NK-cell function in vitro and in vivo, and is associated with glycolysis of ovarian cancer cell. Therapeutically, B7-H3 blockade prolonged the survival of SKOV3 tumor-bearing mice. In addition, miR-29c improved the anti-tumor efficacy of NK-cell by directly targeting B7-H3 in vitro were observed, but not in vivo. CONCLUSION: Our results demonstrate that miR-29c downregulates B7-H3 to inhibit NK-cell exhaustion and associated with glycolysis, which suggest that NK cells may be a new target of anti-B7-H3 therapy in ovarian cancer patients.

Small-molecule inhibitor HI-TOPK-032 improves NK-92MI cell infiltration into ovarian tumours.

The effectiveness of natural killer (NK) cells transferred adoptively in combating solid tumours is limited by challenges such as their difficulty in penetrating tumours from the bloodstream and maintaining viability without the support of interleukin-2 (IL-2). Genetically modified NK-92MI cells, which can release IL-2 to sustain their viability, have been identified as a promising alternative. This adaptation addresses the negative consequences of systemic IL-2 administration. The role of PSD-95/discs large/ZO-1 (PDZ)-binding kinase (PBK) in cancer development is recognized, but its effects on immunity are not fully understood. This study explores how PBK expression influences the ability of NK-92MI cells to infiltrate ovarian tumours. Elevated levels of PBK expression have been found in various cancers, including ovarian cancer (OV), with analyses showing higher PBK mRNA levels in tumour tissues compared to normal ones. Immunohistochemistry has confirmed increased PBK expression in OV tissues. Investigations into PBK's role in immune regulation reveal its association with immune cell infiltration, indicating a potentially compromised immune environment in OV with high PBK expression. The small-molecule inhibitor HI-TOPK-032, which inhibits PBK, enhances the cytotoxicity of NK-92MI cells toward OV cells. It increases the production of interferon-γ and tumour necrosis factor-α, reduces apoptosis and encourages cell proliferation. Mechanistic studies showed that contact with OV cells treated with HI-TOPK-032 upregulates CD107a on NK-92 cells. In vivo studies demonstrated that HI-TOPK-032 improves the antitumour effects of NK-92MI cells in OVCAR3Luc xenografts, extending survival without significant side effects. Safety assessments in mice confirm HI-TOPK-032's favourable safety profile, highlighting its potential as a viable antitumour therapy. These results suggest that combining NK-92MI cells with HI-TOPK-032 enhances antitumour effectiveness against OV, indicating a promising, safe and effective treatment strategy that warrants further clinical investigation.

The prognostic significance of primary tumor site in vulvar cancer: a population-based cohort study.

OBJECTIVE: To investigate the association of primary tumor site with prognosis in vulvar cancer, stratified by vulvar squamous cell carcinoma (SCC) and non-SCC histological types. METHODS: This population-based retrospective study enrolled patients with vulvar cancer from the Surveillance, Epidemiology, and End Results database between January 2000 and December 2018. The primary outcome was cancer-specific survival (CSS). The prognostic difference between labium majus, labium minus and clitoris groups was investigated using Kaplan-Meier analyses and Cox proportional hazards regression analyses. RESULTS: A total of 3,465 eligible patients with vulvar cancer were included with a mean age of 54.5 years. Among the 1,076 (31.1%) patients with non-SCC, the multivariate Cox regression analyses showed that labium minus-sited disease (hazard ratio [HR]=1.85; 95% confidence interval [CI]=1.27-2.71; p=0.001) and clitoris-sited disease (HR=2.37; 95% CI=1.47-3.85; p<0.001) were significantly associated with worse CSS, compared with labium majus-sited disease. However, among the 2,389 (68.9%) patients with SCC, no significant association of primary tumor site with CSS was found (p>0.05). Kaplan-Meier analyses also showed that the primary tumor site had a significant prognostic effect in vulvar non-SCC (p<0.001) but not in vulvar SCC (p=0.330). CONCLUSION: Among vulvar non-SCC, patients with labium minus-sited disease had a significantly worse prognosis than those with labium majus-sited disease, and a significantly better prognosis than those with clitoris-sited disease. Gynecologic oncologists should consider the prognostic effect of primary tumor site in vulvar non-SCC, and make optimal, personalized treatment and surveillance strategies based on different primary tumor sites.

Unraveling the microbial puzzle: exploring the intricate role of gut microbiota in endometriosis pathogenesis.

Endometriosis (EMs) is a prevalent gynecological disorder characterized by the growth of uterine tissue outside the uterine cavity, causing debilitating symptoms and infertility. Despite its prevalence, the exact mechanisms behind EMs development remain incompletely understood. This article presents a comprehensive overview of the relationship between gut microbiota imbalance and EMs pathogenesis. Recent research indicates that gut microbiota plays a pivotal role in various aspects of EMs, including immune regulation, generation of inflammatory factors, angiopoietin release, hormonal regulation, and endotoxin production. Dysbiosis of gut microbiota can disrupt immune responses, leading to inflammation and impaired immune clearance of endometrial fragments, resulting in the development of endometriotic lesions. The dysregulated microbiota can contribute to the release of lipopolysaccharide (LPS), triggering chronic inflammation and promoting ectopic endometrial adhesion, invasion, and angiogenesis. Furthermore, gut microbiota involvement in estrogen metabolism affects estrogen levels, which are directly related to EMs development. The review also highlights the potential of gut microbiota as a diagnostic tool and therapeutic target for EMs. Interventions such as fecal microbiota transplantation (FMT) and the use of gut microbiota preparations have demonstrated promising effects in reducing EMs symptoms. Despite the progress made, further research is needed to unravel the intricate interactions between gut microbiota and EMs, paving the way for more effective prevention and treatment strategies for this challenging condition.

Analysis of the immune checkpoint lymphocyte activation gene-3 (LAG-3) in endometrial cancer: An emerging target for immunotherapy.

BACKGROUND: Lymphocyte activation gene-3 (LAG-3) is a novel molecule that participates in the immune escape of tumor cells and is a target for immunotherapy. However, the expression of LAG-3 in patients with endometrial cancer (EC) has not been comprehensively characterized. OBJECTIVES: We elucidated the expression of LAG-3 and investigated its correlation with clinicopathological parameters, ProMisE subtypes, CD8+ T-cell infiltration and relapse-free survival (RFS) in a retrospective cohort of 421 patients with endometrial cancer. METHODS: Next-generation sequencing of the polymerase epsilon (POLE) and immunohistochemistry of mismatch repair (MMR)-related protein (MLH1, PMS2, MSH2, and MSH6), p53, CD8 and LAG-3 protein in whole sections were performed. RESULTS: Positive LAG-3 was detected in tumor cells (TCs) and immune cells (ICs) in 31.6% (133/421) and 24.0% (101/421) of the patients, respectively. LAG-3 positivity in ICs was more common in high-grade, high-intermediate risk, high-risk, and advanced/metastatic subgroups and was relevant to lymphovascular space invasion, while that in TCs was more common in older individuals (≥54 years). LAG-3 expression was more prevalent in POLE ultramutated (POLEmut) and MMR-deficient (MMRd) EC than in p53-abnormal (p53abn) and p53-wild (p53wt) EC in TCs (34.4 % and 66.3% in POLEmut and MMRd versus 28.6% and 19.5% in p53abn and p53wt, P < 0.001) and ICs (78.1 % and 65.1% in POLEmut and MMRd versus 2.9% and 5.2% in p53abn and p53wt, P < 0.001). Positive expression of LAG-3 in TCs and ICs was associated with high levels of tumor-associated CD8+ T-cell immune infiltration. Additionally, LAG-3 positivity in TCs was related to improved RFS. CONCLUSIONS: This study suggests that immunotherapy targeting LAG-3 may play a role in EC patients with POLEmut or MMRd molecular markers. Positive LAG-3 expression in TCs may be a predictor of improved RFS.

Ferroptosis induced by iron overload promotes fibrosis in ovarian endometriosis and is related to subpopulations of endometrial stromal cells.

Endometriosis (EMs) is defined as the presence of tissue somewhat resembling endometrial glands and stroma outside the uterus; the retrograded endometrium grows in the peritoneal cavity and elicits fibrosis. Ferroptosis is a recently discovered form of programmed cell death, which is iron-dependent. The induction of ferroptosis has been found to participate in fibrosis. However, the relationship between EMs fibrosis and ferroptosis remains unknown. In this study, we confirmed that the iron content in ectopic stromal tissue in ovarian EMs is significantly increased. We explored the role of iron-induced ferroptosis in the pathogenesis of ovarian EMs fibrosis for the first time. We found that ferroptosis in ectopic tissues was significantly enhanced than that in eutopic tissues. Furthermore, we performed in vivo drug screening and found that ferroptosis induced by ferric ammonium citrate (FAC) could aggravate fibrosis. To clarify the mechanism of this process, the stromal composition of human uterine endometrium and endometrial tissue was characterized. Fibroblast-specific protein-1 was used for fibroblasts, smooth muscle actin alpha for myofibroblasts, and platelet-derived growth factor receptor beta (CD140b) for mesenchymal stromal cells (MSCs). The results demonstrated that the percentage of myofibroblasts was higher and the portion of MSCs was lower in ectopic endometrial stroma than those in eutopic endometrium. Moreover, the proportion of MSCs decreased significantly and the percentage of myofibroblasts increased considerably after FAC treatment in vitro. However, disruption of intracellular iron levels or ferroptosis via chelation of intracellular iron deferoxamine mesylate or ferroptosis inhibitor ferrostatin-1 could reverse this process, indicating that iron-induced ferroptosis plays a vital role in ovarian EMs fibrosis. Considering that iron accumulation can feed the Fenton reaction to generate unquenchable amounts of free radicals, causing ferroptosis and tissue damage and thereby contributing to fibrosis, we validated the underlying mechanism that excess iron can facilitate fibrotic responses. Collectively, these data provide evidence that supernumerary iron is a key regulator in promoting MSCs ferroptosis and inducing ovarian EMs fibrosis.

Down-regulation of Exosomal miR-214-3p Targeting CCN2 Contributes to Endometriosis Fibrosis and the Role of Exosomes in the Horizontal Transfer of miR-214-3p.

Endometriosis (EMs) is defined as the presence of tissue which somewhat resembles endometrial glands and stroma outside the uterus, and elicits fibrosis. Fibrosis is the main factor resulting in pain and infertility, while the aetiology of endometrial fibrosis is unknown. There is strong evidence from numerous experiments showing that connective tissue growth factor (CCN2) plays a central role in fibrogenesis. Exosomal miR-214-3p can regulate the expression of CCN2 through binding to complementary sites in the 3' untranslated region. This study aimed to explore the role of exosomal miR-214-3p in endometriosis fibrosis and the relationship between CCN2 and miR-214-3p in endometriosis fibrosis. Our results demonstrated that miR-214-3p was significantly down-regulated and CCN2 was up-regulated in EMs ectopic lesion and stromal cells compared with EMs eutopic and endometrium of patients without endometriosis. Exosomal miR-214-3p can inhibit fibrosis in EMs through targeting CCN2. The results were explored and verified in vitro and in vivo, respectively. Cell co-culture was used to explore the contributions of exosomes to intercellular information transmission of miR-214-3p. The results showed that exosomes play a pivotal role in the transportation of miR-214-3p between cells. Furthermore, level of exosomal miR-214-3p in endometriosis patients' serum was lower than that in patients without endometriosis. In conclusion, exosomal miR-214-3p can inhibit fibrosis in EMs by targeting CCN2. MiR-214-3p may be considered as a bio-marker and has a potential therapeutic effect in EMs.