Current and future immunotherapy approaches in ovarian cancer

Construction of self-driving anti-αFR CAR-engineered NK cells based on IFN-γ and TNF-α synergistically induced high expression of CXCL10

INTRODUCTION

Ovarian cancer is the most malignant gynecological tumor. Previous studies have demonstrated that chimeric antigen receptor (CAR)-engineered NK-92 cells targeting folate receptor α (αFR) (NK-92-αFR-CAR) can specifically kill αFR-positive ovarian cancer cells. However, the migration barrier restricts antitumor effects of CAR-engineered cells.

OBJECTIVES

To elucidate the mechanism by which NK-92-αFR-CAR cells induce the secretion of chemokine CXCL10 during killing ovarian cancer cells. It is speculated that NK-92-αFR-CAR-CXCR3A can target αFR and have chemotaxis of CXCL10, and they may have stronger killing effect of ovarian cancer.

METHODS

Study the mechanism of CXCL10 expression strongly induced by TNF-α and IFN-γ combined stimulation in ovarian cancer cells. Construct the fourth generation of NK-92-αFR-CAR-CXCR3A cells, which were co-expressed CXCR3A and αFR-CAR. Evaluate the killing and migration effects of NK-92-αFR-CAR-CXCR3A in vitro and in vivo.

RESULTS

RNA sequencing (RNA-seq) first revealed that the expression level of the chemokine CXCL10 was most significantly increased in ovarian cancer cells co-cultured with NK-92-αFR-CAR. Secondly, cytokine stimulation experiments confirmed that IFN-γ and TNF-α secreted by NK-92-αFR-CAR synergistically induced high CXCL10 expression in ovarian cancer cells. Further signaling pathway experiments showed that IFN-γ and TNF-α enhanced the activation level of the IFN-γ-IFNGR-JAK1/2-STAT1-CXCL10 signaling axis. Cytotoxicity experiments showed that NK-92-αFR-CAR-CXCR3A cells could not only efficiently kill αFR-positive ovarian cancer cells in vitro but also secrete IFN-γ and TNF-α. Higher migration than that of NK-92-αFR-CAR was detected in NK-92-αFR-CAR-CXCR3A using transwell assay. NK-92-αFR-CAR-CXCR3A effectively killed tumor cells in different mouse xenograft models of ovarian cancer and increased infiltration into tumor tissue.

CONCLUSION

This study confirmed that IFN-γ and TNF-α secreted by αFR-CAR-engineered NK cells can synergistically induce high expression of CXCL10 in ovarian cancer cells and constructed self-driving αFR-CAR-engineered NK cells that can break through migration barriers based on CXCL10, which may provide a new therapeutic weapon for ovarian cancer.

Ecological and evolutionary dynamics to design and improve ovarian cancer treatment

Ovarian cancer ecosystems are exceedingly complex, consisting of a high heterogeneity of cancer cells. Development of drugs such as poly ADP-ribose polymerase (PARP) inhibitors, targeted therapies and immunotherapies offer more options for sequential or combined treatments. Nevertheless, mortality in metastatic ovarian cancer patients remains high because cancer cells consistently develop resistance to single and combination therapies, urging a need for treatment designs that target the evolvability of cancer cells. The evolutionary dynamics that lead to resistance emerge from the complex tumour microenvironment, the heterogeneous populations, and the individual cancer cell's plasticity. We propose that successful management of ovarian cancer requires consideration of the ecological and evolutionary dynamics of the disease. Here, we review current options and challenges in ovarian cancer treatment and discuss principles of tumour evolution. We conclude by proposing evolutionarily designed strategies for ovarian cancer, with the goal of integrating such principles with longitudinal, quantitative data to improve the treatment design and management of drug resistance. KEY POINTS/HIGHLIGHTS: Tumours are ecosystems in which cancer and non-cancer cells interact and evolve in complex and dynamic ways. Conventional therapies for ovarian cancer inevitably lead to the development of resistance because they fail to consider tumours' heterogeneity and cellular plasticity. Eco-evolutionarily designed therapies should consider cancer cell plasticity and patient-specific characteristics to improve clinical outcome and prevent relapse.

Immune pathway through endometriosis to ovarian cancer

Endometriosis is an estrogen-dependent inflammatory disease, defined by the presence of functional endometrial tissue outside of the uterine cavity. This disease is one of the main gynecological diseases, affecting around 10%-15% women and girls of reproductive age, being a common gynecologic disorder. Although endometriosis is a benign disease, it shares several characteristics with invasive cancer. Studies support that it has been linked with an increased chance of developing endometrial ovarian cancer, representing an earlier stage of neoplastic processes. This is particularly true for women with clear cell carcinoma, low-grade serous carcinoma and endometrioid. However, the carcinogenic pathways between both pathologies remain poorly understood. Current studies suggest a connection between endometriosis and endometriosis-associated ovarian cancers (EAOCs) via pathways associated with oxidative stress, inflammation, and hyperestrogenism. This article aims to review current data on the molecular events linked to the development of EAOCs from endometriosis, specifically focusing on the complex relationship between the immune response to endometriosis and cancer, including the molecular mechanisms and their ramifications. Examining recent developments in immunotherapy and their potential to boost the effectiveness of future treatments.

Dual inhibition of BTLA and PD-1 can enhance therapeutic efficacy of paclitaxel on intraperitoneally disseminated tumors

BACKGROUND

Expression of immune checkpoints in the tumor microenvironment is one mechanism underlying paclitaxel (PTX) chemoresistance. This study aimed to investigate whether the addition of checkpoint blockade to PTX can improve the therapeutic efficacy against apparently disseminated intraperitoneal tumors.

METHODS

We analyzed the in vivo expression of various immune checkpoints in CD3⁺CD8⁺ cytotoxic T cells from tumor-bearing mice treated with or without PTX and validated the tumor-killing activities of selected checkpoint-expressing T-cell subpopulations ex vivo. The regulation of selected checkpoints was investigated in vitro. The therapeutic effects of inhibition of a targeted checkpoint pathway with antibodies added to PTX therapy were examined.

RESULTS

CD3⁺CD8⁺ T cells expressed with herpes virus entry mediator (HVEM), programmed cell death 1 (PD-1), and T-cell immunoglobulin domain and mucin domain 3 (TIM-3) in tumor-bearing hosts treated with PTX had effective tumoricidal activities. In addition to PTX and cytokines, B and T lymphocyte attenuator (BTLA) or homologous to lymphotoxin, exhibits inducible expression and competes with herpes simplex virus (HSV) glycoprotein D for binding to HVEM, a receptor expressed on T lymphocytes (LIGHT) interacting with HVEM can regulate the expression of PD-1 on CD3⁺CD8⁺ T cells. Interleukin (IL)-15 increased the percentage of HVEM^highgranzyme B (GZMB)⁺ cells among CD3⁺CD8⁺ T cells, which was suppressed by the BTLA/HVEM signal. LIGHT induced the percentage of HVEM⁺GZMB⁺ cells but not HVEM^highGZMB⁺ cells among CD3⁺CD8⁺ T cells. Expression of IL-15, BTLA, or LIGHT was detected in CD19⁺ B cells and regulated by damage-associated molecular patterns/Toll-like receptor interactions. In the tumor-bearing hosts treated with PTX, certain proportions of BTLA⁺ B or PD-1⁺ T lymphocytes were still noted. When dual inhibition of BTLA and PD-1 was added to PTX, the antitumor effects on intraperitoneally disseminated tumors can be significantly improved.

CONCLUSIONS

Dual blockade of BTLA on B cells and PD-1 on cytotoxic T cells may have clinical potential for enhancing the efficacy of PTX in the treatment of tumors with intraperitoneal spread, including epithelial ovarian carcinomas.

ANKRD22 is a potential novel target for reversing the immunosuppressive effects of PMN-MDSCs in ovarian cancer

BACKGROUND

Ovarian cancer is the deadliest type of malignant gynecological tumor. Polymorphonuclear myeloid-derived suppressor cells (PMN-MDSCs) are involved ovarian cancer and are closely related to adverse outcomes. However, the immunosuppressive mechanism of PMN-MDSCs remains elusive.

METHODS

The types and numbers of ANKRD22-expressing cells were investigated by bioinformatics analysis and immunohistochemical staining. Ankrd22^-/- C57BL/6 mice were constructed with CRISPR-Cas9 technology. Mouse PMN-MDSCs were obtained from bone marrow (BM)-derived CD11b⁺Ly6G⁺Ly6C^low cells sorted by fluorescence-activated cell sorting with treatment of GM-CSF and IL-6, and the immunosuppressive activity of PMN-MDSCs was evaluated by flow cytometry (FCM) and ELISA. The expression level of CCR2 and the exogenous glucose uptake capacity were determined by FCM. RT-qPCR was used to detect ANKRD22 expression in CD11b⁺HLA-DR^-CD14^-CD15⁺ cells from human ovarian cancer tissues, and the correlations of ANKRD22 expression with the clinical characteristics and prognosis of patients were evaluated by the χ² test.

RESULTS

We identified a novel protein involved in regulating the immunosuppressive ability of PMN-MDSCs, ANKRD22. Ankrd22 expression was high in mouse CD11b⁺Ly6G⁺Ly6C^low cells and could be significantly downregulated after exposure to a simulated microenvironmental stimulus. Knockout of Ankrd22 increased the expression level of CCR2 of CD11b⁺Ly6G⁺Ly6C^low cells and the immunosuppressive activity of PMN-MDSCs. BM-derived CD11b⁺Ly6G⁺Ly6C^low cells of Ankrd22^-/- mice significantly promoted the proliferation of ovarian cancer cells in tumor xenograft mouse models. Mechanistically, RNA sequencing showed that Wdfy1 expression was obviously increased in Ankrd22-knockout BM-derived CD11b⁺Ly6G⁺ Ly6C^low cells and that ectopic expression of Wdfy1 increased the levels of Arg1, Inos, Ido and Pdl1 in Ankrd22^+/+ PMN-MDSCs derived from BM-derived CD11b⁺Ly6G⁺Ly6C^low cells. Surprisingly, an ANKRD22-activating candidate small-molecule compound attenuated the immunosuppressive activity of Ankrd22^+/+ PMN-MDSCs. Finally, we found that low ANKRD22 levels in CD11b⁺HLA-DR^-CD14^-CD15⁺ cells derived from primary ovarian tissues were associated with a more advanced International Federation of Gynecology and Obstetrics stage, a higher recurrence rate, and a higher neutrophil-to-lymphocyte ratio.

CONCLUSIONS

These results suggest that ANKRD22 is a potential novel target for reversing the immunosuppressive effects of PMN-MDSCs.

Systematic identification of cancer-associated-fibroblast-derived genes in patients with colorectal cancer based on single-cell sequencing and transcriptomics

Colorectal cancer (CRC) has a high incidence rate and poor prognosis, and the available treatment approaches have limited therapeutic benefits. Therefore, understanding the underlying mechanisms of occurrence and development is particularly crucial. Increasing attention has been paid to the pathophysiological role of cancer-associated fibroblasts (CAFs) in the heterogeneous tumour microenvironment. CAFs play a crucial role in tumorigenesis, tumour progression and treatment response. However, routine tissue sequencing cannot adequately reflect the heterogeneity of tumours. In this study, single-cell sequencing was used to examine the fibroblast population in CRC. After cluster analysis, the fibroblast population was divided into four subgroups. The distribution and role of these four subgroups in CRC were found to be different. Based on differential gene expression and lasso regression analysis of the main marker genes in these subgroups, four representative genes were obtained, namely, TCF7L1, FLNA, GPX3 and MMP11. Patients with CRC were divided into the low- and high-risk groups using the prognostic risk model established based on the expression of these four genes. The prognosis of patients in different risk groups varied significantly; patients with low-risk scores had a greater response to PDL1 inhibitors, significant clinical benefits and significantly prolonged overall survival. These effects may be attributed to inhibition of the function of T cells in the immune microenvironment and promotion of the function of tumour-associated macrophages.

BRCA Mutations in Ovarian and Prostate Cancer: Bench to Bedside

Simple Summary

DNA damage is one of the hallmarks of cancer. Epithelial ovarian cancer (EOC) —especially the high-grade serous subtype—harbors a defect in at least one DNA damage response (DDR) pathway. Defective DDR results from a variety of lesions affecting homologous recombination (HR) and nonhomologous end joining (NHEJ) for double strand breaks, base excision repair (BER), and nucleotide excision repair (NER) for single strand breaks and mismatch repair (MMR). Apart from the EOC, mutations in the DDR genes, such as BRCA1 and BRCA2, are common in prostate cancer as well. Among them, BRCA2 lesions are found in 12% of metastatic castration-resistant prostate cancers, but very rarely in primary prostate cancer. Better understanding of the DDR pathways is essential in order to optimize the therapeutic choices, and has led to the design of biomarker-driven clinical trials. Poly(ADP-ribose) polymerase (PARP) inhibitors are now a standard therapy for EOC patients, and more recently have been approved for the metastatic castration-resistant prostate cancer with alterations in DDR genes. They are particularly effective in tumours with HR deficiency.

Abstract

DNA damage repair (DDR) defects are common in different cancer types, and these alterations can be exploited therapeutically. Epithelial ovarian cancer (EOC) is among the tumours with the highest percentage of hereditary cases. BRCA1 and BRCA2 predisposing pathogenic variants (PVs) were the first to be associated with EOC, whereas additional genes comprising the homologous recombination (HR) pathway have been discovered with DNA sequencing technologies. The incidence of DDR alterations among patients with metastatic prostate cancer is much higher compared to those with localized disease. Genetic testing is playing an increasingly important role in the treatment of patients with ovarian and prostate cancer. The development of poly (ADP-ribose) polymerase (PARP) inhibitors offers a therapeutic strategy for patients with EOC. One of the mechanisms of PARP inhibitors exploits the concept of synthetic lethality. Tumours with BRCA1 or BRCA2 mutations are highly sensitive to PARP inhibitors. Moreover, the synthetic lethal interaction may be exploited beyond germline BRCA mutations in the context of HR deficiency, and this is an area of ongoing research. PARP inhibitors are in advanced stages of development as a treatment for metastatic castration-resistant prostate cancer. However, there is a major concern regarding the need to identify reliable biomarkers predictive of treatment response. In this review, we explore the mechanisms of DDR, the potential for genomic analysis of ovarian and prostate cancer, and therapeutics of PARP inhibitors, along with predictive biomarkers.

Combining PARP inhibition and immune checkpoint blockade in ovarian cancer patients: a new perspective on the horizon?

Immune checkpoint inhibitors (ICIs) have completely reshaped the treatment of many malignancies, with remarkable improvements in survival outcomes. In ovarian cancer (OC), however, this emerging class of drugs has not yet found a favorable use due to results from phase I and II studies, which have not suggested a substantial antitumoral activity of these agents when administered as monotherapy. Robust preclinical data seem to suggest that the combination ICIs with poly(ADP-ribose) polymerase (PARP) inhibitors (PARPis) may result in a synergistic activity; furthermore, data from phase II clinical studies, evaluating this combination, have shown encouraging outcomes especially for those OC patients not suitable for platinum retreatment. While waiting for ongoing phase III clinical trial results, which will clarify the role of ICIs in combination with PARPis in the newly diagnosed OC, this review aims to summarize the preclinical data and clinical evidence available to date.

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Preclinical data indicate that PARPis exhibit immune modulating properties.

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The combination of PARPi with ICIs displays significant synergistic activity in preclinical models.

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Phase I and II clinical trials showed encouraging results for this combination, especially in platinum-resistant OC.

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Four ongoing phase III trials exploring the combination in first-line setting will delineate the role of immunotherapy in OC.

Aberrant Expression of ADARB1 Facilitates Temozolomide Chemoresistance and Immune Infiltration in Glioblastoma

Chemoresistance, especially temozolomide (TMZ) resistance, is a major clinical challenge in the treatment of glioblastoma (GBM). Exploring the mechanisms of TMZ resistance could help us identify effective therapies. Adenosine deaminases acting on RNA (ADARs) are very important in RNA modification through regulating the A-to-I RNA editing. Recent studies have shown that ADARs regulate multiple neurotransmitter receptors, which have been linked with the occurrence and progress of GBM. Here, data from several bioinformatics databases demonstrated that adenosine deaminase RNA specific B1 (ADARB1), also named ADAR2, was upregulated in both GBM tissues and cells, and had the prognostic value in GBM patients. Moreover, ADARB1 was found to be involved in AKT-mediated TMZ resistance in GBM cells. The KEGG analysis of ADARB1-associated co-expressed genes showed that ADARB1 was potentially involved in the mitochondrial respiratory chain complex. TISIDB and GEPIA databases were further used to analyze the role of ADARB1 in tumor-immune system interactions in GBM. These findings deepened our understanding of the function of ADARB1 in tumorigenesis and therapeutic response in GBM.

Downregulated ADARB1 Facilitates Cell Proliferation, Invasion and has Effect on the Immune Regulation in Ovarian Cancer

Ovarian cancer (OC) is typically diagnosed at an advanced stage and poses a significant challenge to treatment and recovery. Rencently, Adenosine deaminase RNA-specific B1 (ADARB1), an adenosine-to-inosine (A-to-I) RNA-editing enzyme, has been found to play an essential role in the development of cancer. However, the specific function of ADARB1 in ovarian cancer is still not fully understood. Here, we investigated the effects of ADARB1 on OC biology. By conducting bioinformatics analyses of several public databases, we found significantly decreased ADARB1 expression in OC cells and tissues. Moreover, RT-PCR and western blot showed lower ADARB1 expression in OVCAR3, HO8910pm and A2780 OC cells compared to human normal ovarian epithelial cell IOSE. Cell proliferation assay and clone formation assay showed that overexpression of ADARB1 (ADARB1-OE) inhibited the proliferation of tumor cells. Wound healing and transwell assay indicated that ADARB1-OE could suppress OC cell invasion and metastasis. Kaplan-Meier methods revealed that the patients with low level of ADARB1 displayed poor prognosis. TISIDB databases were further used to analyze the roles of ADARB1 in tumor-immune system interactions in OC patients. Furthermore, ADARB1-OE down-regulated the expression of phosphorylated AKT. Combination of ADARB1-OE and AKT inhibitor MK2206 exerted stronger cell growth inhibition. Thus, our investigation demonstrated that low levels of ADARB1 might be a potential target in the tumorigenesis and prognostic evaluation of OC patients.

PD-1/PD-L1 Inhibitors Monotherapy for the Treatment of Endometrial Cancer: Meta-Analysis and Systematic Review

PURPOSE

The efficacy of programmed cell death protein 1(PD-1)/Programmed cell death 1 ligand 1 (PD-L1) inhibitors for endometrial cancer remain controversial, and guidelines are inconsistent on which are preferred therapies for advanced disease, or who develop metastases and recurrence. Therefore, we aimed to estimate the efficacy and safety of PD-1/PD-L1 inhibitors in endometrial cancer on a more complete database by adding multiple randomized trials.

METHODS

A systematic and comprehensive search was carried out in PD-1/PD-L1 inhibitors monotherapy.

RESULTS

The ORR of PD-1/PDL-1 inhibitors was 29%, and subgroup analysis showed that the pooled ORR of the proficient mismatch repair (pMMR) group was 4% and which was 45% of the deficient mismatch repair (dMMR) group. The DCR of PD-1/PD-L1 inhibitors was 48%, through subgroup analysis, we found that the DCR of the pMMR group was 21% and which was 58% of the dMMR group. The proportion of patients occurring overall adverse events was 65% and grade three or higher adverse events was 14%. The proficient mismatch repair (pMMR) group and the deficient mismatch repair (dMMR) group showed different results.

CONCLUSION

PD-1/PD-L1 inhibitors had shown little success in the pMMR population and better efficacy in the dMMR population.

Basics of immunotherapy for epithelial ovarian cancer

Epithelial ovarian cancer (EOC) is the most lethal of all gynecological cancers. Despite excellent responses to standard treatment in approximately 70% of patients, most of them will relapse within 5 years of initial treatment and many of them will develop chemotherapy-resistant disease. It is then important to find other means of treatment for these patients such as immunotherapy or targeted therapy. To understand immunotherapy, it is important to explain the dynamic interplay between cancer and the immune system. Compared to traditional tumor therapies, immunotherapy acts primarily on the immune system or the tumor microenvironment but not directly on the tumor cells, and it may also promote synergistic anti-tumor actions as part of a combined treatment. The aim of this narrative review is to provide a basic understanding of immunotherapy the interest of this treatment in EOC, and to present the main ongoing studies that could change patient management in the future.

Significance of TEAD Family in Diagnosis, Prognosis and Immune Response for Ovarian Serous Carcinoma

PURPOSE

To explore the molecular profiles of transcriptional enhanced associate domain (TEAD) family in ovarian serous carcinoma (OSC).

METHODS

In this study, we use bioinformatics methods including GEPIA, GE-mini, Oncomine 3.0, Kaplan-Meier plotter, cBioPortal, WebGestalt, TIMER2.0 and DiseaseMeth2.0, and in vitro experimental RT-PCR to assess the expression profiles and prognostic significance of TEAD family in OSC.

RESULTS

According to the bioinformatics analysis, TEAD family was abnormally expressed in OSC. In terms of prognosis, Kaplan-Meier plotter indicated that OSC patients with high level of TEAD4 showed poor overall survival (OS), progression-free survival (PFS) and post progression survival (PPS). TEAD family also had significantly diagnostic values for OSC patients. Tumor Immune Estimation Resource (TIMER) algorithm indicated that TEAD family was significantly associated with different types of infiltrating immune cells, including B cells, macrophages, dendritic cells, neutrophils, CD8+ T cells and CD4+ T cells. Gene set enrichment analysis of TEAD family-associated coexpression genes was further explored. In in vitro experiments, the RT-PCR results showed the upregulated TEAD2/4 in OSC tissues and cells (A2780 and TOV112D). Moreover, decreased expression of TEAD2 could induce the ferroptosis through increasing the ROS accumulation.

CONCLUSION

Thus, TEAD family correlated with the diagnosis, prognosis and immune infiltration in OSC. These results could provide comprehensive understanding of TEAD family in the diagnosis and prognosis of OSC patients.

Obesity and gynecological cancers: A toxic relationship

Despite the evidence supporting the relevance of obesity and obesity‐associated disorders in the development, management, and prognosis of various cancers, obesity rates continue to increase worldwide. Growing evidence supports the involvement of obesity in the development of gynecologic malignancies. This article explores the molecular basis governing the alteration of hallmarks of cancer in the development of obesity‐related gynecologic malignancies encompassing cervical, endometrial, and ovarian cancers. We highlight specific examples of how development, management, and prognosis are affected for each cancer, incorporate current knowledge on complementary approaches including lifestyle interventions to improve patient outcomes, and highlight how new technologies are helping us better understand the biology underlying this neglected pandemic.

This review focuses on how obesity impacts cancer hallmarks in gynecologic malignancies, thus affecting the diagnosis, management, treatment, and prognosis of these diseases.

The Immune-Related Gene ELF3 is a Novel Biomarker for the Prognosis of Ovarian Cancer

Background

Ovarian cancer (OC) is a fatal gynaecological malignancy. The study aimed to conduct a comprehensive study to determine the role of ELF3 in OC through bioinformatic analysis.

Methods

Kruskal-Wallis test, Wilcoxon sign-rank test, and logistic regression were used to evaluate the relationship between clinical characteristics and ELF3 expression. Kaplan-Meier method and Cox regression analysis were used to evaluate the prognostic factors. Gene set enrichment analysis (GSEA) and immuno-infiltration analysis were used to evaluate the significant involvement of ELF3 in function.

Results

High ELF3 expression in OC was associated with age (P< 0.001). High ELF3 expression predicted a poorer overall survival (OS) (HR: 1.37; 95% CI: 1.05-1.78; P=0.019) and disease specific survival (DSS) (HR: 1.43; 95% CI: 1.08-1.89; P=0.013). And ELF3 expression (HR: 1.779; 95% CI: 1.281-2.472; P<0.001) was independently correlated with OS in OC patients. GSEA demonstrated that pathways including GPCR-ligand binding, neuronal system, signaling by WNT, translation, neuroactive ligand-receptor interaction, and TCF dependent signaling in response to WNT were differentially enriched in ELF3 low expression phenotype. Immune infiltration analysis showed that ELF3 expression was correlated with immune infiltrates.

Conclusion

ELF3 expression in OC patients was significantly associated with poor survival and immune infiltration and a promising prognostic biomarker in OC.

Immunotherapy in rare ovarian cancer

PURPOSE OF REVIEW

Ovarian cancer (OC) is a heterogeneous disease and a mounting body of evidence shows that a 'one-size-fits-all' approach is obsolete. Differences in epidemiology, tumor biology, genetic profiles and treatment responses of these different types necessitate a tumor and patient-specific approach. Ninety percentage consists of epithelial OC with 70% being high-grade serous OC. The other rarer subtypes are low-grade serous (5%), clear cell (12%), endometrioid (11%) and mucinous carcinoma (3%). The remaining 10% are nonepithelial rare OCs: germ cell (3%) and sex-cord stromal tumors (7%).

RECENT FINDINGS

Over the past few decades, the 5-year survival rates have only improved modestly, therefore novel therapies are urgently needed. Recently, immunotherapy has been introduced into clinical practice in a number of solid tumors. Although preclinical data confirm the presence of an immunogenic microenvironment in a number of ovarian tumor types, no single-agent immune checkpoint inhibitor has been approved hitherto. Identifying suitable treatment combinations, adequate patient selection and thus correct implementation of immunotherapy remain major challenges.

SUMMARY

In this review, we focus on the rationale of incorporating immune therapy in rare OC, we summarize the recent developments with preclinical data and results of clinical trials, with particular focus on rare ovarian histological subtypes.

Immune cell infiltration-associated signature in colon cancer and its prognostic implications

Tumor immune cell infiltration (ICI) has been reported in various studies to be correlated with tumor diagnosis, clinical treatment sensitivity and prognosis. It is an important direction to study the characteristics of immune cell infiltration and develop new prognostic markers to improve the treatment of colon cancer. In this paper, we systematically analyzed the ICI characteristics and obtained three ICI clusters. Then, the ICI scores were constructed and its prognostic implications were discussed. From the results, the ICI score patterns were linked to a great survival difference (p<0.001). A high ICI score was characterized by a higher fraction of plasma cells, CD8+ T cells, memory resting CD4+ T cells, monocytes, eosinophils and dendritic cells, which had better prognosis. Macrophages and neutrophils were increased in low ICI score patients with decreased overall survival. Immune checkpoint molecules (PDCD1, CD274, LAG3, IDO1, CTLA-4, TIGHT and HAVCR2) were found to be significantly overexpressed in the low ICI score subgroup. In addition, we also studied the correlation between the tumor mutation burden (TMB) and ICI score. This study indicated the ICI score could serve as a potential prognostic biomarker for colon cancer patients' immunotherapy.

The Role of Myeloid-Derived Suppressor Cells (MDSCs) in the Development and/or Progression of Endometriosis-State of the Art

Endometriosis (EMS) is a common gynecological disease characterized by the presence of endometrial tissue outside the uterus. Approximately 10% of women around the world suffer from this disease. Recent studies suggest that endometriosis has potential to transform into endometriosis-associated ovarian cancer (EAOC). Endometriosis is connected with chronic inflammation and changes in the phenotype, activity, and function of immune cells. The underlying mechanisms include quantitative and functional disturbances of neutrophils, monocytes/macrophages (MO/MA), natural killer cells (NK), and T cells. A few reports have shown that immunosuppressive cells such as regulatory T cells (Tregs) and myeloid-derived suppressor cells (MDSCs) may promote the progression of endometriosis. MDSCs are a heterogeneous population of immature myeloid cells (dendritic cells, granulocytes, and MO/MA precursors), which play an important role in the development of immunological diseases such as chronic inflammation and cancer. The presence of MDSCs in pathological conditions correlates with immunosuppression, angiogenesis, or release of growth factors and cytokines, which promote progression of these diseases. In this paper, we review the impact of MDSCs on different populations of immune cells, focusing on their immunosuppressive role in the immune system, which may be related with the pathogenesis and/or progression of endometriosis and its transformation into ovarian cancer.

Lynch Syndrome: Its Impact on Urothelial Carcinoma

Lynch syndrome, known as hereditary nonpolyposis colorectal cancer (HNPCC), is an autosomal-dominant familial cancer syndrome with an increased risk for urothelial cancer (UC). Mismatch repair (MMR) deficiency, due to pathogenic variants in MLH1, MSH2, MSH6, and PMS2, and microsatellite instability, are known for development of Lynch syndrome (LS) associated carcinogenesis. UC is the third most common cancer type in LS-associated tumors. The diversity of germline variants in the affected MMR genes and their following subsequent function loss might be responsible for the variation in cancer risk, suggesting an increased risk of developing UC in MSH2 mutation carriers. In this review, we will focus on LS-associated UC of the upper urinary tract (UUT) and bladder, their germline profiles, and outcomes compared to sporadic UC, the impact of genetic testing, as well as urological follow-up strategies in LS. In addition, we present a case of metastatic LS-associated UC of the UUT and bladder, achieving complete response during checkpoint inhibition since more than 2 years.