Ovarian cancer and the immune system - The role of targeted therapies

Characterizing the genomic landscape through the lens of FOLR1 status in low and high grade serous ovarian carcinoma

OBJECTIVE

Targeted therapy in folate receptor alpha (FOLR1)-positive high grade serous ovarian carcinoma (HGSOC) is now a mainstay for platinum-resistant disease. However, the rate of FOLR1-positivity in low grade serous ovarian carcinoma (LGSOC) is not well documented. Less common than HGSOC, LGSOC tends to respond poorly to traditional platinum-based chemotherapeutic regimens, particularly in recurrence. Thus, there is an urgent need to identify molecular targets that may assist in identifying more efficacious treatments for LGSOC. In this work, we assessed the genomic and transcriptomic landscapes in FOLR1-positive/negative LGSOC compared to its high-grade counterpart.

METHODS

Using a large precision oncology database, next-generation sequencing and immunohistochemistry was performed on a cohort of 281 LGSOC and 5086 HGSOC. Associated MAPK activation was calculated based on NGS results and patient survival analysis was completed stratified by molecular alteration.

RESULTS

Compared with LGSOC (24.6 %), HGSOC tumors have significantly higher prevalence of FOLR1+ status (43.5 %) and significantly higher PD-L1+ status. Conversely, LGSOC had higher prevalence of KRAS and NRAS mutations, with a near exclusivity for BRAF mutation compared to HGSOC. FOLR1- LGSOC and HGSOC had similar prevalences of T cell-inflamed tumors, though FOLR1+ LGSOC had a significantly lower prevalence of T-Cell inflamed tumors than FOLR1+ HGSOC. MAPK activation, quantified via MAPK activation score (MPAS), was significantly higher in low-grade tumors compared to HGSOC, yet no difference between FOLR1+ vs FOLR1- LGSOC was observed.

CONCLUSIONS

Though less than in high-grade disease, a notable portion of low-grade tumors were FOLR1+, suggesting FOLR1 expression in LGSOC could be a viable target for this rare histology, particularly in the recurrent setting.

The Putative Effects of Neoadjuvant Chemotherapy on the Immune System of Advanced Epithelial Ovarian Carcinoma

The epithelial ovarian carcinoma (EOC) is one of leading causes of cancer-related mortality in females. For some patients, complete resection cannot be achieved, thus neoadjuvant chemotherapy (NACT) following interval debulking surgery (IDS) could be an alternative choice. In general-held belief, cytotoxic chemotherapy is assumed to be immunosuppressive, because of its toxicity to dividing cells in the bone marrow and peripheral lymphoid tissues. However, increasing evidence highlighted that the anticancer activity of chemotherapy may also be related to its ability to act as an immune modulator. NACT not only changed the morphology of cancer cells, but also changed the transcriptomic and genomic profile of EOC, induced proliferation of cancer stem-like cells, gene mutation, and tumor-related adaptive immune response. This review will provide a comprehensive overview of recent studies evaluating the impact of NACT on cancer cells and immune system of advanced EOC and their relationship to clinical outcome. This information could help us understand the change of immune system during NACT, which might provide new strategies in future investigation of immuno-therapy for maintenance treatment of EOC.

Prognostic features of the tumor microenvironment in high-grade serous ovarian cancer and dietary immunomodulation

High-grade serous ovarian cancer (HGSOC) is a particularly lethal malignancy that is prognostically influenced by the immune profile of the tumor microenvironment (TME). TME immune profiles have been sub-categorized according to features associated with both survival outcomes as well as response to systemic therapies. Five suggested immune phenotypes have been described and correlated with overall survival outcomes. Phenotypes associated with shorter overall survival rates appear to have prominent immunosuppressive features within their TME. The opportunity to triage patients according to their prognostic TME profile might allow selection of individual patients with poor prognostic features who could most benefit from innovative immunomodulatory treatment strategies. Two potential strategies to indirectly manipulate the TME (and oncologic outcomes) are alteration of the gut microbiome composition and alteration of TME metabolism through dietary interventions. Experimental dietary modifications in humans designed for influencing cancer outcomes are only beginning to be studied in a prospective fashion. Herein we summarize prognostic TME features in HGSOC and potential opportunities for immunomodulation via dietary and gut microbial interventions.

Novel immune-related gene signature for risk stratification and prognosis prediction in ovarian cancer

BACKGROUND

The immune system played a multifaceted role in ovarian cancer (OC) and was a significant mediator of ovarian carcinogenesis. Various immune cells and immune gene products played an integrated role in ovarian cancer (OC) progression, proved the significance of the immune microenvironment in prognosis. Therefore, we aimed to establish and validate an immune gene prognostic signature for OC patients' prognosis prediction.

METHODS

Differently expressed Immune-related genes (DEIRGs) were identified in 428 OC and 77 normal ovary tissue specimens from 9 independent GEO datasets. The Cancer Genome Atlas (TCGA) cohort was used as a training cohort, Univariate Cox analysis was used to identify prognostic DEIRGs in TCGA cohort. Then, an immune gene-based risk model for prognosis prediction was constructed using the LASSO regression analysis, and validated the accuracy and stability of the model in 374 and 93 OC patients in TCGA training cohort and International Cancer Genome Consortium (ICGC) validation cohort respectively. Finally, the correlation among risk score model, clinicopathological parameters, and immune cell infiltration were analyzed.

RESULTS

Five DEIRGs were identified to establish the immune gene signature and divided OC patients into the low- and high-risk groups. In TCGA and ICGC datasets, patients in the low-risk group showed a substantially higher survival rate than high-risk group. Receiver operating characteristic (ROC) curves, t-distributed stochastic neighbor embedding (t-SNE) analysis and principal component analysis (PCA) showed the good performance of the risk model. Clinicopathological correlation analysis proved the risk score model could serve as an independent prognostic factor in 2 independent datasets.

CONCLUSIONS

The prognostic model based on immune-related genes can function as a superior prognostic indicator for OC patients, which could provide evidence for individualized treatment and clinical decision making.

Impact of Sepsis on the Oncologic Outcomes of Advanced Epithelial Ovarian Cancer Patients: A Multicenter Observational Study

OBJECTIVE

The sepsis-induced inflammatory response may potentially affect malignant cells. Recently, a case of spontaneous regression of a histologically confirmed International Federation of Gynecology and Obstetrics (FIGO) stage IIIC epithelial ovarian cancer (EOC) following sepsis was reported. The aim of our study was to assess the impact of sepsis on the oncologic outcomes of advanced-stage EOC patients.

METHODS

Gynecologic oncologic patients admitted to the Intensive Care Unit of three oncologic centers between 2006 and 2019 were identified and patients who experienced sepsis following advanced-stage EOC diagnosis were selected. Survival outcomes were compared with advanced-stage EOC patients from the Netherlands Cancer Registry (NCR). To correct for case-mix differences, propensity score matching using 1:3 nearest neighbor matching was conducted after which survival analyses were repeated.

RESULTS

A total of 18 of 215 patients with advanced-stage EOC experienced sepsis. Sepsis patients had similar distributions of patient, tumor, and treatment characteristics to 3988 patients from the NCR cohort. A total of 3 of 18 patients died from the complications of sepsis. While the remaining patients initially responded to treatment, 14/15 patients relapsed. The median (IQR) overall survival was 31 (24-44) and 35 (20-60) months for the sepsis and unmatched NCR cohort (p = 0.56), respectively. The median (IQR) progression-free survival was 16 (11-21) and 16 (11-27) months (p = 0.90), respectively. Survival outcomes did not differ following propensity matching (overall survival of 31 (24-44) vs. 36 (20-56) months, p = 0.40; progression-free survival of 16 (11-21) and 16 (12-21) months, p = 0.72).

CONCLUSION

In this observational study, the occurrence of sepsis did not affect the oncologic and survival outcomes of advanced-stage EOC patients.

Molecular cluster mining of high-grade serous ovarian cancer via multi-omics data analysis aids precise medicine

PURPOSE

HGSOC is a kind of gynecological cancer with high mortality and strong heterogeneity. The study used multi-omics and multiple algorithms to identify novel molecular subtypes, which can help patients obtain more personalized treatments.

METHODS

Firstly, the consensus clustering result was obtained using a consensus ensemble of ten classical clustering algorithms, based on mRNA, lncRNA, DNA methylation, and mutation data. The difference in signaling pathways was evaluated using the single-sample gene set enrichment analysis (ssGSEA). Meanwhile, the relationship between genetic alteration, response to immunotherapy, drug sensitivity, prognosis, and subtypes was further analyzed. Finally, the reliability of the new subtype was verified in three external datasets.

RESULTS

Three molecular subtypes were identified. Immune desert subtype (CS1) had little enrichment in the immune microenvironment and metabolic pathways. Immune/non-stromal subtype (CS2) was enriched in the immune microenvironment and metabolism of polyamines. Immune/stromal subtype (CS3) not only enriched anti-tumor immune microenvironment characteristics but also enriched pro-tumor stroma characteristics, glycosaminoglycan metabolism, and sphingolipid metabolism. The CS2 had the best overall survival and the highest response rate to immunotherapy. The CS3 had the worst prognosis and the lowest response rate to immunotherapy but was more sensitive to PARP and VEGFR molecular-targeted therapy. The similar differences among three subtypes were successfully validated in three external cohorts.

CONCLUSION

We used ten clustering algorithms to comprehensively analyze four types of omics data, identified three biologically significant subtypes of HGSOC patients, and provided personalized treatment recommendations for each subtype. Our findings provided novel views into the HGSOC subtypes and could provide potential clinical treatment strategies.

Prognostic role of different PD-L1 expression patterns and tumor-infiltrating lymphocytes in high-grade serous ovarian cancer: a systematic review and meta-analysis

Background

The prognostic value of programmed cell death ligand 1 (PD-L1) expression and tumor-infiltrating lymphocytes (TILs) in high-grade serous ovarian cancer (HGSOC) remains a controversial topic in the research field. To comprehensively assess the importance of PD-L1 and TILs in this particular subtype of ovarian cancer, we performed a meta-analysis.

Methods

We conducted a comprehensive search of PubMed, Embase, Scopus, Web of Science, and Cochrane Library databases up to December 25, 2022. The association between PD-L1, TILs, and survival outcomes was evaluated using the combined hazard ratios (HRs) and their corresponding 95% confidence intervals (CIs).

Results

This meta-analysis comprised 11 trials involving a total of 1746 cases. The results revealed no significant association between PD-L1 expression in tumor cells (TCs) and overall survival (OS, HR = 0.76, 95% CI: 0.52-1.09, p = 0.136) or progression-free survival (PFS, HR = 0.71, 95% CI: 0.4 -1.24, p = 0.230). Nevertheless, a correlation was observed between PD-L1 expression in immune cells (ICs) and OS (HR = 0.73, 95% CI: 0.55-0.97, p = 0.031). Furthermore, the presence of CD8+ and PD-1+ TILs was found to significantly enhance OS (HR = 0.70, 95% CI = 0.55-0.87, p = 0.002; HR = 0.57, 95% CI = 0.40-0.80, p = 0.001, respectively) and PFS (HR = 0.62, 95% CI = 0.41-0.92, p = 0.019; HR = 0.52, 95% CI = 0.35-0.78, p = 0.002, respectively), whereas the presence of CD3+ and CD4+ TILs was positively associated with OS (HR = 0.50, 95% CI = 0.29-0.87, p = 0.014; HR = 0.55, 95% CI = 0.34-0.91, p = 0.020, respectively).

Conclusion

This study indicates a positive correlation between ICs-derived PD-L1 and survival, while no significant correlation was observed between TCs-derived PD-L1 and prognosis. These results highlight the importance of studying PD-L1 expression in ICs as a prognostic predictor. In addition, the presence of TILs was found to significantly improve patient survival, suggesting that TILs may be a valuable prognostic biomarker.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42022366411.

Glucose-6-phosphate dehydrogenase: a therapeutic target for ovarian cancer

INTRODUCTION

Ovarian cancer (OC) is a gynecological tumor disease, which is usually diagnosed at an advanced stage and has a poor prognosis. It has been established that the glucose metabolism rate of cancer cells is significantly higher than that of normal cells, and the pentose phosphate pathway (PPP) is an important branch pathway for glucose metabolism. Glucose-6-phosphate dehydrogenase (G6PD) is the key rate-limiting enzyme in the PPP, which plays an important role in the initiation and development of cancer (such as OC), and has been considered as a promisinganti-cancer target.

AREAS COVERED

In this review, based on the structure and biological function of G6PD, recent research on the roles of G6PD in the progression, metastasis, and chemoresistance of OC are summarized and accompanied by proposed molecular mechanisms, which may provide a systematic understanding of targeting G6PD for the treatment of patients with OC.

EXPERT OPINION

Accumulating evidence demonstrates that G6PD is a promising target of cancer. The development of G6PD inhibitors for cancer treatment merits broad application prospects.

Advances in immunotherapy for gynecological malignancies

To date, surgery, chemotherapy and radiotherapy are mainly used to treat or remove gynecological malignancies. However, these approaches have their limitations when facing complicated female diseases such as advanced cervical and endometrial cancer (EC), chemotherapy-resistant gestational trophoblastic neoplasia and platinum-resistant ovarian cancer. Instead, immunotherapy, as an alternative, could significantly improve prognosis of those patients receiving traditional treatments, with better antitumor activities and possibly less cellular toxicities. Its' development is still not fast enough to meet the current clinical needs. More preclinical studies and larger-scale clinical trials are required. This review aims to introduce the landscape and up-to-date status of immunotherapy against gynecological malignancies, with a discussion of the challenges and future direction.

Drug Repurposing for Targeting Myeloid-Derived Suppressor-Cell-Generated Immunosuppression in Ovarian Cancer: A Literature Review of Potential Candidates

The lethality of patients with ovarian cancer (OC) remains high. Current treatment strategies often do not lead to the desired outcome due to the development of therapy resistance, resulting in high relapse rates. Additionally, clinical trials testing immunotherapy against OC have failed to reach significant results to date. The OC tumor microenvironment and specifically myeloid-derived suppressor cells (MDSC) are known to generate immunosuppression and inhibit the anti-tumor immune response following immunotherapy treatment. Our review aims to characterize potential candidate treatments to target MDSC in OC through drug-repurposing. A literature search identified repurposable compounds with evidence of their suppressing the effect of MDSC. A total of seventeen compounds were withheld, of which four were considered the most promising. Lurbinectedin, metformin, celecoxib, and 5-azacytidine have reported preclinical effects on MDSC and clinical evidence in OC. They have all been approved for a different indication, characterizing them as the most promising candidates for repurposing to treat patients with OC.

SAMHD1 expression modulates innate immune activation and correlates with ovarian cancer prognosis

Purpose

SAMHD1 is a deoxynucleotide triphosphate (dNTP) triphosphohydrolase which has been proposed as a putative prognostic factor in haematological cancers and certain solid tumours, although with controversial data. Here, we evaluate SAMHD1 function in ovarian cancer, both in vitro and in ovarian cancer patients.

Methods

SAMHD1 expression was downregulated in ovarian cancer cell lines OVCAR3 and SKOV3 by RNA interference. Gene and protein expression changes in immune signalling pathways were assessed. SAMHD1 expression in ovarian cancer patients was evaluated by immunohistochemistry and survival analysis was performed according to SAMHD1 expression.

Results

SAMHD1 knockdown induced a significant upregulation of proinflammatory cytokines concomitant to increased expression of the main RNA-sensors, MDA5 and RIG-I, and interferon-stimulated genes, supporting the idea that the absence of SAMHD1 promotes innate immune activation in vitro. To assess the contribution of SAMHD1 in ovarian cancer patients, tumours were stratified in SAMHD1-low and SAMHD1-high expressing tumours, resulting in significantly shorter progression free survival (PFS) and overall survival (OS) in SAMHD1-high expression subgroup (p=0.01 and 0.04, respectively).

Conclusions

SAMHD1 depletion correlates with increased innate immune cell signalling in ovarian cancer cells. In clinical samples, SAMHD1-low expressing tumors showed increased progression free survival and overall survival irrespective of BRCA mutation status. These results point towards SAMHD1 modulation as a new therapeutic strategy, able to enhance innate immune activation directly in tumour cells, leading to improved prognosis in ovarian cancer.

High expression of CD8 in the tumor microenvironment is associated with PD-1 expression and patient survival in high-grade serous ovarian cancer

Objective:

The current study assesses programmed death-1 (PD-1) receptor expression and CD3, CD4, and CD8 tumor-infiltrating lymphocytes (TILs) in high-grade serous ovarian cancer (HGSOC) and associates our results with neoadjuvant chemotherapy history and disease prognosis.

Materials and Methods:

We included cases diagnosed with primary HGSOC with biopsy or surgical resection materials in this study. The immunoreactivity of CD3, CD4, CD8, and PD1 was assessed immunohistochemically in tumor tissue. We analyzed TILs in two predetermined groups of high and low TIL. The relationships between clinical characteristics, PD-1, and TIL were assessed. by the χ⁽²⁾ test or Fisher’s Exact test. We used Kaplan-Meier survival analysis and Cox proportional hazards regression model to the connection between survival and the amounts of TIL, and PD1.

Results:

Univariate analysis demonstrated that optimal debulking (p<0.001), early International Federation of Gynecology and Obstetrics stage (p=0.046), and higher scores of stromal CD8+ TIL expression (p=0.028) in tumor cells were all substantially correlated with longer disease-free survival (DFS), whereas the remaining variables analyzed, including PD-1 positivity, stromal CD3+, and CD4+ TILs, and intraepithelial CD3+, CD4+, and CD8+ TILs, were not correlated with DFS. Also, univariate analysis revealed that optimal debulking (p=0.010), and higher scores of stromal CD8+ TIL expression (p=0.021) in tumor cells were all substantially correlated with longer overall survival (OS).

Conclusion:

Higher scores of stromal CD8+ TILs are substantially correlated with DFS and OS in univariate analyses, whereas scores of stromal CD3+ and CD4+ TILs, and intraepithelial CD3+, CD4+, and CD8+ TILs are not correlated with DFS and OS in both univariate and multivariate analyses. Also, we found a significant association between PD-1 positivity and the scores of stromal CD3+ TILs and intraepithelial CD8+ TILs. However, no remarkable relationship was revealed between PD-1 positivity and the survival of HGSOC cases.

Peripheral lymphocyte populations in ovarian cancer patients and correlations with clinicopathological features

Background

To investigate the alterations of peripheral lymphocyte subpopulations in ovarian cancer patients compared to benign or borderline counterparts. The possible clinicopathological implications were also evaluated.

Methods

We enrolled 112 treatment-naive ovarian cancer patients, 14 borderline tumor patients and 44 benign tumor patients between 09/2016 and 01/2019. Flow cytometry was used to measure the peripheral lymphocyte subsets consisting of T cells (CD3⁺, CD3⁺CD4⁺, CD3⁺CD8⁺ and CD8⁺CD28⁺), regulatory T cells (Tregs, CD4⁺CD25⁺CD127⁻), natural killer cells (NK cells, CD3⁻CD56⁺) and B cells (CD19⁺).

Results

Most ovarian cancer patients were high-grade serous carcinoma (84.8%), followed by clear cell carcinoma (8.03%). Late-stage tumor (FIGO III + IV) accounted for 82.1%. The study showed that the proportions of peripheral lymphocyte subsets underwent apparent changes in ovarian cancer patients. We observed elevated levels of Treg cells in patients with both ovarian borderline and malignant tumor compared to those with benign tumors, which achieved statistic significance. In contrast, CD3⁺CD8⁺ T and CD8⁺CD28⁺ T cells were significantly lower in ovarian cancer patients. Interestingly, low level of B cells was correlated to clear cell carcinoma (P = 0.024), advanced tumor (P = 0.028) and platinum-resistant recurrence (P = 0.014). Regarding the changes of lymphocyte subsets after surgery, CD8⁺CD28⁺ T cells had a significant decreasing tendency (P = 0.007) while B cells were the opposite (P < 0.001).

Conclusions

Ovarian cancer patients have altered circulating lymphocyte profile (elevated Treg cell, depressed CD3⁺CD8⁺ T and CD8⁺CD28⁺ T cells). Low level of B cells might be related to disease aggressiveness, and it recovered after the removal of tumor, which merits further study.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13048-022-00977-3.

1 Ovarian cancer patients have altered circulating lymphocyte profile

2 Low level of B cells might be related to disease aggressiveness, and it recovered after the removal of tumor.

Strategies for active tumor targeting-an update

A complete cure for cancer is still the holy grail for scientists. The existing treatment of cancer is primarily focused on surgery, radiation and conventional chemotherapy. However, chemotherapeutic agents also affect healthy tissues or organs due to a lack of specificity. While passive targeting is studied for anticancer drugs focused on the enhanced permeability and retention effect, it failed to achieve drug accumulation at the tumor site and desired therapeutic efficacy. This review presents an outline of the current significant targets for active tumor drug delivery systems and provides insight into the direction of active tumor-targeting strategies. For this purpose, a systematic understanding of the physiological factors, tumor microenvironment and its components, overexpressed receptor and associated proteins are covered here. We focused on angiogenesis mediated targeting, receptor-mediated targeting and peptide targeting. This active targeting along with integration with nano delivery systems helps in achieving specific action, thus reducing the associated adverse effects to healthy tissues. Although the tumor-targeting methods and possibilities explored so far seem revolutionary in cancer treatment, in-depth clinical studies data is required for its commercial translation.

Survival impact of bowel resection at the time of interval cytoreductive surgery for advanced ovarian cancer

Objectives

To evaluate the impact of bowel resection at the time of interval cytoreductive surgery on survival.

Methods

We identified patients with advanced ovarian cancer who underwent neoadjuvant chemotherapy and interval cytoreductive surgery between 2008 and 2018 from a single-institution tumor registry. Kaplan-Meier survival analysis and Cox proportional hazards models were performed comparing patients who underwent bowel resection to those who did not.

Results

Of 158 patients, 43 (27%) underwent bowel resection. Rates of optimal (95%) and sub-optimal (5%) resection did not differ with bowel resection. Patients that required bowel resection had worse three-year survival (43% vs. 63%), even after adjusting for confounding variables of age, stage, number of neoadjuvant cycles, R0 resection, and ASA score (HR 2.27, p < 0.01). Adjusted progression-free survival did not differ between groups (HR 0.92, p = 0.72). Patients who underwent bowel resection were more likely to require blood transfusion (p < 0.01), and have a longer hospital stay (5 days vs 7.5 days, p < 0.01).

Conclusions

Bowel resection at the time of interval cytoreduction confers a greater than 2-fold increased risk of mortality and does not impact progression-free survival. Long-term sequelae of the peri-operative morbidity of bowel resection may contribute to increased mortality, and bowel resection may be a surrogate for disease biology with poor prognosis.

Long non-coding RNA FOXP4-AS1 is a prognostic biomarker and associated with immune infiltrates in ovarian serous cystadenocarcinoma

BACKGROUND

FOXP4-AS1 expression participates in multiple signal pathways and has been previously reported in colorectal cancer, cervical cancer, and other cancer cells. However, its role on prognosis and immune infiltrates in ovarian serous cystadenocarcinoma (OVs) remains unclear. The purpose of our study was to investigate the expression of FOXP4-AS1 in OVs and its association with immune infiltrates, and determined its prognostic roles in OVs.

METHODS

Using The Cancer Genome Atlas (TCGA) database, we retrieved FOXP4-AS1 expression and clinical information for 376 patients with OVs. Wilcoxon rank sum test was used to compare the expression of FOXP4-AS1 in OVs and normal ovarian tissue. Logistic regression was used to analyze the relationship between clinicopathologic features and FOXP4-AS1. Gene Set Enrichment Analysis (GSEA), and single sample Gene Set Enrichment Analysis (ssGSEA) was conducted to investigate the enrich pathways and functions and quantify the extent of immune cells infiltration for FOXP4-AS1. Kaplan-Meier method was used to generate survival curves, and Cox regression was used to analyze the relationship between FOXP4-AS1 and survival rate.

RESULTS

High FOXP4-AS1 expression was significantly correlated with tumor FIGO stage (P = .026). Multivariate survival analysis showed that FOXP4-AS1was an independent prognostic marker for overall survival (OS; hazard ratio [HR]: 0.638; 95% confidence interval [CI]:0.467-0.871; P = .001) and disease-specific survival (DSS; HR: 0.649; CI: 0.476-0.885; P = .006). GSEA showed that High FOXP4-AS1 expression may active programmed cell death 1 (PD-1) signaling, the cytotoxic T lymphocyte-associated antigen-4 (CTLA4) pathway, the B cell receptor signaling pathway, apoptosis, fibroblast growth factor receptor (FGFR) signaling, and the Janus-activated kinase signal transducers and activators of transcription (JAK-STAT) signaling pathway. FOXP4-AS1 expression was negatively correlated with markers of immune cells, including aDC, cytotoxic cells and neutrophils.

CONCLUSION

High FOXP4-AS1 expression has the potential to be a prognostic molecular marker of favorable survival in OVs.

FOXM1: A Multifunctional Oncoprotein and Emerging Therapeutic Target in Ovarian Cancer

Forkhead box M1 (FOXM1) is a member of the conserved forkhead box (FOX) transcription factor family. Over the last two decades, FOXM1 has emerged as a multifunctional oncoprotein and a robust biomarker of poor prognosis in many human malignancies. In this review article, we address the current knowledge regarding the mechanisms of regulation and oncogenic functions of FOXM1, particularly in the context of ovarian cancer. FOXM1 and its associated oncogenic transcriptional signature are enriched in >85% of ovarian cancer cases and FOXM1 expression and activity can be enhanced by a plethora of genomic, transcriptional, post-transcriptional, and post-translational mechanisms. As a master transcriptional regulator, FOXM1 promotes critical oncogenic phenotypes in ovarian cancer, including: (1) cell proliferation, (2) invasion and metastasis, (3) chemotherapy resistance, (4) cancer stem cell (CSC) properties, (5) genomic instability, and (6) altered cellular metabolism. We additionally discuss the evidence for FOXM1 as a cancer biomarker, describe the rationale for FOXM1 as a cancer therapeutic target, and provide an overview of therapeutic strategies used to target FOXM1 for cancer treatment.

Research Progress in Prognostic Factors and Biomarkers of Ovarian Cancer

Ovarian cancer is a serious threat to women's health; its early diagnosis rate is low and prone to metastasis and recurrence. The current conventional treatment for ovarian cancer is a combination of platinum and paclitaxel chemotherapy based on surgery. The recurrence and progression of ovarian cancer with poor prognosis is a major challenge in treatment. With rapid advances in technology, understanding of the molecular pathways involved in ovarian cancer recurrence and progression has increased, biomarker-guided treatment options can greatly improve the prognosis of patients. This review systematically discusses and summarizes existing and new information on prognostic factors and biomarkers of ovarian cancer, which is expected to improve the clinical management of patients and lead to effective personalized treatment.

The systemic treatment of recurrent ovarian cancer revisited

Treatment approaches for relapsed ovarian cancer have evolved over the past decade from a calendar-based decision tree to a patient-oriented biologically driven algorithm. Nowadays, platinum-based chemotherapy should be offered to all patients with a reasonable chance of responding to this therapy. The treatment-free interval for platinum is only one of many factors affecting patients' eligibility for platinum re-treatment. Bevacizumab increases the response to chemotherapy irrespective of the cytotoxic regimen and can be valuable in patients with an urgent need for symptom relief (e.g. pleural effusion, ascites). For patients with recurrent high-grade ovarian cancer, which responds to platinum-based treatment, maintenance therapy with a poly(ADP-ribose) polymerase inhibitor can be offered, regardless of the BRCA mutation status. Here we review contemporary decision-making processes in the systemic treatment of relapsed ovarian cancer.

Neutralization of TGFβ Improves Tumor Immunity and Reduces Tumor Progression in Ovarian Carcinoma

The immunosuppressive effects of TGFβ promotes tumor progression and diminishes response to therapy. In this study, we used ID8-p53^-/- tumors as a murine model of high-grade serous ovarian cancer. An mAb targeting all three TGFβ ligands was used to neutralize TGFβ. Ascites and omentum were collected and changes in T-cell response were measured using flow. Treatment with anti-TGFβ therapy every other day following injection of tumor cells resulted in decreased ascites volume (4.1 mL vs. 0.7 mL; P < 0.001) and improved the CD8:Treg ratio (0.37 vs. 2.5; P = 0.02) compared with untreated mice. A single dose of therapy prior to tumor challenge resulted in a similar reduction of ascites volume (2.7 vs. 0.67 mL; P = 0.002) and increased CD8:Tregs ratio (0.36 vs. 1.49; P = 0.007), while also significantly reducing omental weight (114.9 mg vs. 93.4 mg; P = 0.017). Beginning treatment before inoculation with tumor cells and continuing for 6 weeks, we observe similar changes and prolonged overall survival (median 70 days vs. 57.5 days). TGFβ neutralization results in favorable changes to the T-cell response within the tumor microenvironment, leading to decreased tumor progression in ovarian cancer. The utilization of anti-TGFβ therapy may be an option for management in patients with ovarian cancer to improve clinical outcomes and warrants further investigation.

Chemotherapy sensitivity testing on ovarian cancer cells isolated from malignant ascites

BACKGROUND

In epithelial ovarian cancer (EOC), 15-20% of the tumors do not respond to first-line chemotherapy (paclitaxel with platinum-based therapy), and in recurrences this number increases. Our aim is to determine the feasibility of cell proliferation assays of tumor cells isolated from malignant ascites to predict in vitro chemotherapy sensitivity, and to correlate these results with clinical outcome.

MATERIALS AND METHODS

Ascites was collected from twenty women with advanced EOC. Cell samples were enriched for tumor cells and EOC origin was confirmed by intracellular staining of CK7, surface staining of CA125 and EpCAM, and HE4 gene expression. In vitro sensitivity to chemotherapy was determined in cell proliferation assays using intracellular ATP content as an indirect measure of cell number. In vitro drug response was quantified by calculation of the drug concentration at which cell growth was inhibited with 50%. Clinical outcome was determined using post-treatment CA125 level.

RESULTS

Cell samples of twenty patients were collected, of which three samples that failed to proliferate were excluded in the analysis (15%). Three other samples were excluded, because clinical outcome could not be determined correctly. In twelve of the fourteen remaining cases (86%) in vitro drug sensitivity and clinical outcome corresponded, while in two samples (14%) there was no correspondence.

CONCLUSIONS

Our study demonstrates the feasibility of drug sensitivity tests using tumor cells isolated from ascites of advanced EOC patients. Larger observational studies are required to confirm the correlation between the in vitro sensitivity and clinical outcome.

Characterization of immunoreactivity with whole-slide imaging and digital analysis in high-grade serous ovarian cancer

Ovarian cancer is the most lethal of gynecological cancers with 5-year survival rate of ca. 45%. The most common histologic subtype is high-grade serous carcinoma, which typically is presented with advanced stage and development of chemoresistance. Therefore, new treatment options, including immunotherapies, are needed. Understanding the features of the immune cell populations in the tumor microenvironment is essential for developing personalized treatments and finding predictive biomarkers. Digital image analysis may enhance the accuracy and reliability of immune cell infiltration assessment in the tumor microenvironment. The aim of this study was to characterize tumor microenvironment in a retrospective cohort of high-grade serous carcinoma samples with whole-slide imaging and digital image analysis. Formalin-fixed paraffin-embedded high-grade serous carcinoma tumor tissue samples (n = 67) were analyzed for six immunohistochemical stainings: CD4, CD8, FoxP3, granzyme B, CD68, and CD163. The stained sample slides were scanned into a digital format and assessed using QuPath 0.1.2 and ImageJ software. Staining patterns were associated with clinicopathological data. The higher numbers of intraepithelial CD8+, CD163+, and granzyme B+ immune cells were associated with survival benefit when analyzed individually, while high levels of both CD8+ and granzyme B+ tumor-infiltrating lymphocytes were an independent prognostic factor in the Cox multivariate regression analysis (median progression-free survival; hazard ratio = 0.287, p = 0.002). Specimens taken after administration of neoadjuvant chemotherapy presented with lower FoxP3+ tumor-infiltrating lymphocyte density (Fisher's exact test, p = 0.013). However, none of the studied immunomarkers was associated with overall survival or clinical factors. Tumors having high amount of both intraepithelial CD8+ and granzyme B+ tumor-infiltrating lymphocytes showed better progression-free survival, possibly reflecting an activated immune state in the tumor microenvironment. The combined positivity of CD8 and granzyme B warrants further investigation with respect to predicting response to immune therapy. Neoadjuvant chemotherapy may have an effect on the tumor microenvironment and therefore on the response to immuno-oncologic or chemotherapy treatments.

An association of iNKT+/CD3+/CD161+ lymphocytes in ovarian cancer tissue with CA125 serum concentration

The purpose of this study was to investigate the association of iNKT (human invariant natural killer T) cells with the key marker of ovarian cancer (OC) - CA125 (cancer antigen125) in serum. The study reports the assessment of iNKT cells in peripheral blood and tissue of benign and borderline ovarian tumors (BOTs) and in the advanced-stage ovarian cancer. The study groups were as follows: 25 women with benign ovarian tumors, 11 women with BOTs, and 24 women with primary advanced-stage ovarian cancers. The control group consisted of 20 patients without the ovarian pathology. The rates of iNKT lymphocytes in the peripheral blood and tissue specimens were evaluated by a flow cytometry. Significant differences in the percentage of iNKT+/CD3+ of CD3+ lymphocytes, iNKT+/CD3+/CD161+ among CD3+ and iNKT+/CD3+/CD161+ among CD3+/iNKT+ between the control group and patients with ovarian tumors in the peripheral blood and tumor tissue were identified. Significant correlations were noticed between the proportion of lymphocytes iNKT+/CD3+/CD161+ among CD3+/iNKT cells in blood and in cancer tissue of both benign and malignant tumors. In the OC group, neither the ratio of iNKT cells in the blood (P = 0.07), nor the intra-tumor NKT-cell infiltration (P = 0.5) were independent prognostic factors for the follow-up. An increased rate of iNKT cells was detected in benign ovarian tumors compared to OCs. In patients with ovarian cancer, a higher rate of iNKT cells in tumor tissue was present related to that noted in the patient's blood. In addition, a correlation was discovered between the CA125 serum marker and NKT cells from the ovarian cancer tissue. This article has for the first time demonstrated a negative relationship between serum levels and NKT lymphocyte count from ovarian tissue. The inflammatory process in ovarian cancer tissue and the potential infiltration of endothelial immune cells, may result in a reduced number of NKT cells in the tumor microenvironment and increased circulation of the CA125 marker. Presented findings underscore new aspects of the iNKT cells involvement in the ovarian cancer development.

Overexpression of long noncoding RNA PTPRG-AS1 is associated with poor prognosis in epithelial ovarian cancer

OBJECTIVE Long noncoding RNAs (lncRNAs) have been shown to play a critical role in tumor progression. Abnormal expression of LncRNA PTPRG antisense RNA 1 (PTPRG-AS1) has been reported in several tumors. Hence, we aimed to determine the expression and clinical significance of PTPRG-AS1 in epithelial ovarian cancer (EOC) patients. METHODS The expressions of PTPRG-AS1 were assessed in 184 pairs of EOC tumor specimens and adjacent normal tissues. The levels of target lncRNAs and GAPDH were examined using standard SYBR-Green methods. The relationships between the expressions of PTPRG-AS1 and the clinicopathological features were analyzed using the chi-square test. Multivariate analysis using the Cox proportional hazards model was performed to assess the prognostic value of PTPRG-AS1 in EOC patients. RESULTS We confirmed that the expressions of PTPRG-AS1 were distinctly higher in the EOC tissue compared with the adjacent non-tumor specimens (p < 0.01). Higher levels of PTPRG-AS1 in EOC patients were associated with advanced FIGO stage (p = 0.005), grade (p = 0.006), and distant metastasis (p = 0.005). Survival analyses revealed that patients with high expressions of PTPRG-AS1 had a distinctly decreased overall survival (p = 0.0029) and disease-free survival (p = 0.0009) compared with those with low expressions of PTPRG-AS1. Multivariate assays indicated that PTPRG-AS1 expression was an independent prognostic factor for both overall survival and disease-free survival in EOC (Both p < 0.05). CONCLUSIONS Our study suggests that PTPRG-AS1 may serve as a novel prognostic biomarker for EOC patients.

Plasma Gelsolin Inhibits CD8+ T-cell Function and Regulates Glutathione Production to Confer Chemoresistance in Ovarian Cancer

Although initial treatment of ovarian cancer is successful, tumors typically relapse and become resistant to treatment. Because of poor infiltration of effector T cells, patients are mostly unresponsive to immunotherapy. Plasma gelsolin (pGSN) is transported by exosomes (small extracellular vesicle, sEV) and plays a key role in ovarian cancer chemoresistance, yet little is known about its role in immunosurveillance. Here, we report the immunomodulatory roles of sEV-pGSN in ovarian cancer chemoresistance. In chemosensitive conditions, secretion of sEV-pGSN was low, allowing for optimal CD8⁺ T-cell function. This resulted in increased T-cell secretion of IFNγ, which reduced intracellular glutathione (GSH) production and sensitized chemosensitive cells to cis-diaminedichloroplatinum (CDDP)-induced apoptosis. In chemoresistant conditions, increased secretion of sEV-pGSN by ovarian cancer cells induced apoptosis in CD8⁺ T cells. IFNγ secretion was therefore reduced, resulting in high GSH production and resistance to CDDP-induced death in ovarian cancer cells. These findings support our hypothesis that sEV-pGSN attenuates immunosurveillance and regulates GSH biosynthesis, a phenomenon that contributes to chemoresistance in ovarian cancer. SIGNIFICANCE: These findings provide new insight into pGSN-mediated immune cell dysfunction in ovarian cancer chemoresistance and demonstrate how this dysfunction can be exploited to enhance immunotherapy.

"Acquired" NKG2D Ligand Stimulates NK Cell-mediated Tumor Immunosurveillance

Engagement of activating receptor NKG2D to its ligand mediates natural killer (NK) cell activation and enhances cytotoxicity. NKG2D ligands (NKG2DLs) are frequently expressed on the tumor cell surface. However, the expression patterns of different NKG2DLs vary between tumor cells. Downregulation of certain ligand enables the tumor cells to escape NK cell-mediated immunosurveillance. By generating tumor cell lines with high expression of NKG2D ligand MULT1, we aimed to explore the function of NKG2DLs diversity on the activation and regulation of NKG2D signaling pathway. NK cells were potently activated by the "acquired" MULT1 expression on MOVCAR 5009 cells. Further, the progression of the tumor was significantly inhibited in mice inoculated with MULT1-expressing MOVCAR 5009 cells. Also, the pulmonary metastasis of MULT1-expressing B16-F0 cells was also significantly reduced in vivo. Our results implied that "acquired" NKG2D ligands enhance antitumor responses of NK cells, providing insights for designing novel therapeutic strategies and drugs to enhance NK cell surveillance over malignances.

A gene signature for immune subtyping of desert, excluded, and inflamed ovarian tumors

PROBLEM

The current tumor immunology paradigm emphasizes the role of the immune tumor microenvironment and distinguishes several histologically and transcriptionally different immune tumor subtypes. However, the experimental validation of such classification is so far limited to selected cancer types. Here, we aimed to explore the existence of inflamed, excluded, and desert immune subtypes in ovarian cancer, as well as investigate their association with the disease outcome.

METHOD OF STUDY

We used the publicly available ovarian cancer dataset from The Cancer Genome Atlas for developing subtype assignment algorithm, which was next verified in a cohort of 32 real-world patients of a known tumor subtype.

RESULTS

Using clinical and gene expression data of 489 ovarian cancer patients in the publicly available dataset, we identified three transcriptionally distinct clusters, representing inflamed, excluded, and desert subtypes. We developed a two-step subtyping algorithm with COL5A2 serving as a marker for separating excluded tumors, and CD2, TAP1, and ICOS for distinguishing between inflamed and desert tumors. The accuracy of gene expression-based subtyping algorithm in a real-world cohort was 75%. Additionally, we confirmed that patients bearing inflamed tumors are more likely to survive longer.

CONCLUSION

Our results highlight the presence of transcriptionally and histologically distinct immune subtypes among ovarian tumors and emphasize the potential benefit of immune subtyping as a clinical tool for treatment tailoring.

The Controversial Role of PD-1 and Its Ligands in Gynecological Malignancies

The programmed death-1 (PD-1, CD279) receptor with its ligands, programmed death ligand 1 (PD-L1, CD274, B7-H1), and programmed death ligand 2 (PD-L2, CD273, B7-DC), are the key players of one of the immune checkpoint pathways inhibiting T-cell activation. PD-L1 and PD-L2 are expressed in different cancer cells and their microenvironment, including infiltrating immune cells. However, their prognostic value is still debated and their role in the tumor microenvironment has not been fully elucidated yet. Considering the importance that cancer immunotherapy with anti-PD-1 and anti-PD-L1 antibodies gained in several tumor types, in this review article we aim to discuss the role of the PD-1/PD-L1/PD-L2 axis in gynecological cancers. PD-1 ligands have been detected in ovarian, cervical, vulvar and uterine cancers, and correlation with prognosis seems dependent from their distribution. About PD-L2, very few reports are available so far in gynecological malignancies, and its role is still not completely understood. Clinical trials using anti-PD-1 or anti-PD-L1 antibodies, but not anti-PD-L2, are currently ongoing, in all types of gynecological cancers. They have shown good safety profiles in a certain cohort of patients, but response rates remain low and many aspects remain controversial. In this review, we propose possible solutions to enhance the clinical efficacy of PD-1 axis targeting therapies. Regarding PD-L2, it might be useful to better clarify its role in order to improve the efficiency of immunotherapy in female malignancies.

Pharmaceutical Management of Ovarian Cancer: Current Status

For more than 20 years, the combination of a platinum agent and a taxane has served as the primary chemotherapy strategy for epithelial ovarian cancer. Alternative approaches employing these drugs (intraperitoneal drug delivery, neoadjuvant therapy) have favorably impacted outcomes in selected patient populations. Multiple single agent and combination therapy strategies have been delivered in the second-line (or later) setting with the goal to prolong survival and optimize quality-of-life. The anti-angiogenic agent bevacizumab has been shown to be clinically active when added to chemotherapy and delivered as a "maintenance" strategy in the front-line, platinum-sensitive recurrent and platinum-resistant settings. Several poly-(ADP-ribose) polymerase (PARP) inhibitors are currently utilized as single-agent "second-line" treatment options or in the maintenance setting. Recent clinical research efforts in ovarian cancer have focused on the potential role of checkpoint inhibitors used alone or in combination with PARP inhibitors or anti-angiogenic agents.

Effect of Dexmedetomidine-Mediated Insulin-Like Growth Factor 2 (IGF2) Signal Pathway on Immune Function and Invasion and Migration of Cancer Cells in Rats with Ovarian Cancer

Background

The aim of this study was to explore the effect of dexmedetomidine (DEX)-mediated insulin-like growth factor 2 (IGF2) signal pathway on immune function and cancer cell invasion and migration in rats with ovarian cancer.

Material/Methods

Forty rats with ovarian cancer were divided into 4 groups: model group, and low dose (0.2 μg/kg/hour DEX), medium dose (1.0 μg/kg/hour DEX), and high dose (5.0 μg/kg/hour DEX) DEX groups. In addition, 10 Fischer344 rats were selected as a normal group. Human NUTU-19 poorly differentiated epithelial ovarian cancer cell line cells were divided into 4 groups: a blank group and low dose, medium dose, and high dose DEX NUTU-19 groups.

Results

Compared with the normal group, in the other groups the serum interleukin (IL)-2 and interferon gamma (INF-γ) levels, CD4⁺ and CD8⁺ percentages, CD4⁺/CD8⁺ ratio, and transformation rate of splenic lymphocytes were decreased, and the serum tumor necrosis factor alpha (TNF-α) level, IGF2, insulin-like growth factor 1 receptor (IGF1R), insulin receptor substrate 1 (IRS1) mRNA, and protein expressions in ovarian tissue were increased (all P<0.05). Results in the DEX groups compared with model group were the opposite of those in the other groups compared with normal group (all P<0.05). Compared with the blank group, in the other groups the proliferation, invasion, and migration of ovarian cancer cells were reduced significantly (all P<0.05). Compared with the low dose DEX NUTU-19 group, in the high dose DEX NUTU-19 group the invasion and migration of ovarian cancer cells weakened significantly (both P<0.05).

Conclusions

A certain dose of DEX can effectively inhibit IGF2 signal pathway activation to improve the immune function of rats with ovarian cancer, inhibiting the invasion and migration of ovarian cancer cells.

Myeloid Derived Suppressor Cells: Key Drivers of Immunosuppression in Ovarian Cancer

The presence of tumor infiltrating lymphocytes (TILs) is associated with a longer overall survival in advanced stage epithelial ovarian cancer. Despite the prognostic impact of TILs, response to checkpoint-inhibitors and antigen-specific active immunotherapy is limited in ovarian cancer. The goal of our study was to investigate the interaction between ovarian cancer and the innate and adaptive immune system in the ID8-fLuc syngeneic ovarian cancer mouse model. For the in vivo experiments C57BL/6, B6.129S7-Rag1^tm1Mom/J, and B6.129P2(SJL)-Myd88^tm1.1Defr/J mice were inoculated with ID8-fLuc. In vivo depletion experiments were performed using clodronate liposomes (CL), anti-CD8a, anti-GR1, anti-colony stimulating factor 1 (anti-CSF1), and TMβ1 (anti-CD122). Immune read out was performed by fluorescent activated cell sorting analysis for effector T cells, regulatory T cells, natural killer cells, B cells, macrophages, and myeloid derived suppressor cells (MDSC), immunohistochemistry for MDSC and tumor-associated macrophages (TAM) and immunofluorescence for M1 and M2 TAM in the vascular context. The effect of MDSC on T cell proliferation and phenotype were studied in vitro. We discovered that the absence of T and B cells did not influence tumor growth or survival of B6.129S7-Rag1^tm1Mom/J mice compared to immunocompetent C57BL/6 mice. CL-induced macrophage depletion promoted tumor proliferation and shortened survival in C57BL/6 mice (p = 0.004) and in B6.129S7-Rag1^tm1Mom/J mice (p = 0.0005). During CL treatment, we observed a clear increase of pro-inflammatory cytokines (p ≤ 0.02) and monocytic MDSC (p ≤ 0.01). Selective depletion of MDSC by anti-GR1 improved survival, certainly in comparison to mice treated with anti-CSF1 (p = 0.01-median survival 91 vs. 67.5 days). B6.129P2(SJL)-Myd88^tm1.1Defr/J mice displayed to a longer median survival compared to C57BL/6 mice (90 vs. 76 days). MDSC activated by ID8-fLuc conditioned medium or ascites of tumor-bearing mice showed T cell suppressive functions in vitro. Based on these findings, we conclude that the adaptive immune system does not efficiently control tumor growth in the ID8-fLuc model. In addition, we discovered a prominent role for MDSC as the driver of immunosuppression in the ID8-fLuc ovarian cancer mouse model.

Epigenetic therapy for ovarian cancer: promise and progress

Ovarian cancer is the deadliest gynecologic malignancy, with a 5-year survival rate of approximately 47%, a number that has remained constant over the past two decades. Early diagnosis improves survival, but unfortunately only 15% of ovarian cancers are diagnosed at an early or localized stage. Most ovarian cancers are epithelial in origin and treatment prioritizes surgery and cytoreduction followed by cytotoxic platinum and taxane chemotherapy. While most tumors will initially respond to this treatment, recurrence is likely to occur within a median of 16 months for patients who present with advanced stage disease. New treatment options separate from traditional chemotherapy that take advantage of advances in understanding of the pathophysiology of ovarian cancer are needed to improve outcomes. Recent work has shown that mutations in genes encoding epigenetic regulators are mutated in ovarian cancer, driving tumorigenesis and resistance to treatment. Several of these epigenetic modifiers have emerged as promising drug targets for ovarian cancer therapy. In this article, we delineate epigenetic abnormalities in ovarian cancer, discuss key scientific advances using epigenetic therapies in preclinical ovarian cancer models, and review ongoing clinical trials utilizing epigenetic therapies in ovarian cancer.

Cytokine-induced memory-like natural killer cells have enhanced function, proliferation, and in vivo expansion against ovarian cancer cells

OBJECTIVE

Natural killer (NK) cells are lymphocytes well suited for adoptive immunotherapy. Attempts with adoptive NK cell immunotherapy against ovarian cancer have proven unsuccessful, with the main limitations including failure to expand and diminished effector function. We investigated if incubation of NK cells with interleukin (IL)-12, IL-15, and IL-18 for 16h could produce cytokine-induced memory-like (CIML) NK cells capable of enhanced function against ovarian cancer.

METHODS

NK cells were preactivated briefly with IL-12, IL-15, and IL-18, rested, then placed against ovarian cancer targets to assess phenotype and function via flow cytometry. Real-time NK-cell-mediated tumor-killing was evaluated. Using ascites cells and cell-free ascites fluid, NK cell proliferation and function within the immunosuppressive microenvironment was evaluated in vitro. Finally, CIML NK cells were injected intraperitoneal (IP) into an in vivo xenogeneic mouse model of ovarian cancer.

RESULTS

CIML NK cells demonstrate enhanced cytokine (IFN-γ) production and NK-cell-mediated killing of ovarian cancer. NK cells treated overnight with cytokines led to robust activation characterized by temporal shedding of CD16, induction of CD25, and enhanced proliferation. CIML NK cells proliferate more with enhanced effector function compared to controls in an immunosuppressive microenvironment. Finally, human CIML NK cells exhibited potent antitumor effects within a xenogeneic mouse model of ovarian cancer.

CONCLUSIONS

CIML NK cells have enhanced functionality and persistence against ovarian cancer in vitro and in vivo, even when exposed to ascites fluid. These findings provide a strategy for NK cell-based immunotherapy to circumvent the immunosuppressive nature of ovarian cancer.

Spontaneous Regression of Ovarian Carcinoma After Septic Peritonitis; A Unique Case Report

Despite advances in therapy, ovarian cancer remains the most lethal gynecological malignancy and prognosis has not substantially improved over the past 3 decades. Immunotherapy is a promising new treatment option. However, the immunosuppressive cancer microenvironment must be overcome for immunotherapy to be successful. Here, we present a unique case of spontaneous regression of ovarian carcinoma after septic peritonitis. A 79-year-old woman was diagnosed with stage IIIc ovarian cancer. The omental cake biopsy was complicated by sepsis. Although the patient recovered, her physical condition did not allow further treatment for her ovarian cancer. After 6 months, spontaneous regression of the tumor was observed during surgery. Analysis of the immune infiltrate in the tissues showed a shift from a pro-tumorigenic to an anti-tumorigenic immune response after sepsis. Strong activation of the immune system during sepsis overruled the immunosuppressive tumor microenvironment and allowed for a potent anti-tumor immune response. More understanding of immunological responses in cases with cancer and septic peritonitis might be crucial to identify potential new targets for immunotherapy.

Smac combined with DDP can inhibit drug resistance of ovarian cancer through regulation of Survivin expression

Ovarian cancer has the highest mortality rate among gynecological malignancies, presenting a major threat to women's life and health. It is essential to study the mechanisms of drug resistance to chemotherapy to identify ways to enhance drug-sensitivity. In recent years, many studies have shown that Smac/DIABLO is closely related to tumor drug resistance. Smac/DIABLO expression is markedly different between drug-resistant and chemo sensitive tumor cells. Up-regulation of Smac/DIABLO has been shown to increase tumor cell chemotherapy sensitivity. We found that Smac, combined with DDP greatly inhibited proliferation of subcutaneous xenografts of ovarian cancer cell line SKOV3/DDP without side effects. Mechanistic studies showed that Smac can inhibit the expression of Survivin, promote cell apoptosis of drug-resistant ovarian cancer cells and reverse the drug resistance.

Patient inflammatory status and CD4+/CD8+ intraepithelial tumor lymphocyte infiltration are predictors of outcomes in high-grade serous ovarian cancer

BACKGROUND

High-grade serous ovarian cancer (HGSOC) is the most prevalent and aggressive histologic type of ovarian cancer. To date, there are no reliable biomarkers to effectively predict patient prognosis. Studies have demonstrated inflammation and tumor infiltrating lymphocytes (TILs) correlate with a bad and good prognosis, respectively. Here, we sought to evaluate systemic inflammation and TILs as early prognostic markers of survival.

METHODS

Neutrophil-to-lymphocyte ratio (NLR) and serum Lactate Dehydrogenase (LDH) were used as indicators of systemic inflammation. NLR, serum LDH, tumor infiltrating lymphocytes (TILs), PDL1 and quality of debulking surgery were evaluated as determinants of progression-free survival (PFS) and overall survival (OS) in a cohort of 128 HGSOC patients.

RESULTS

Initial univariate analysis showed that systemic inflammation measures (NLR and serum LDH), debulking surgery, and intra-epithelial TILs have a significant impact on both PFS and OS. After adjustment for several variables, multivariate analyses confirmed intraepithelial CD4+ T-cells, systemic inflammation measures, PDL1 and debulking surgery as determinants of better OS and PFS.

CONCLUSIONS

Systemic inflammation and TILs are early determinants of OS in HGSOC. Other variables such as the quality of debulking surgery and PDL1 also improve survival of patients. Regarding TIL sub-populations, intraepithelial CD4+ cells are associated to an increase in both PFS and OS. We also confirmed previous reports that demonstrate intraepithelial CD8+ cells correlate with an increase on PFS in ovarian cancer. A combined score using systemic inflammation and TILs may be of prognostic value for HGSOC patients.

Anti-CD73 and anti-OX40 immunotherapy coupled with a novel biocompatible enzyme prodrug system for the treatment of recurrent, metastatic ovarian cancer

Approximately 75% of ovarian cancer is diagnosed once metastasis to the peritoneal cavity has occurred. A large proportion of patients eventually develop platinum-resistive tumors, which are considered terminal. In order to provide an alternative a novel fusion protein, mCTH-ANXA5, has been developed for the treatment of recurrent, metastatic ovarian cancer. The fusion protein combines annexin V (ANXA5), an ovarian tumor and tumor vasculature targeting protein, with mutated cystathionine gamma-lyase (mCTH), an enzyme that converts selenomethionine (SeMet) into toxic methylselenol, which generates reactive oxygen species and eventual tumor cell death. In order to further enhance the therapeutic efficacy, anti-CD73 and anti-OX40 immunostimulants were combined with mCTH-ANXA5, resulting in an increase of survival by 100% from 12 to 24 days post-therapy and decrease tumor burden in mice with orthotopic metastatic ovarian cancer. Further evaluation of the combination therapy revealed a strong antibody-mediated immune response, and an increased infiltration of cytotoxic T-cells along with a decrease in tumor promoting immune cells. This study demonstrates the efficacy of a synergistic, multi-drug system by attacking the tumor as well as enlisting the body's own defense system to treat the patient.

Dynamics of the Intratumoral Immune Response during Progression of High-Grade Serous Ovarian Cancer

PURPOSE

Tumor-infiltrating lymphocytes (TILs) have an established impact on the prognosis of high-grade serous ovarian carcinoma (HGSOC), however, their role in recurrent ovarian cancer is largely unknown. We therefore systematically investigated TIL densities and MHC class I and II (MHC1, 2) expression in the progression of HGSOC.

EXPERIMENTAL DESIGN

CD3+, CD4+, CD8+ TILs and MHC1, 2 expression were evaluated by immunohistochemistry on tissue microarrays in 113 paired primary and recurrent HGSOC. TILs were quantified by image analysis. All patients had been included to the EU-funded OCTIPS FP7 project.

RESULTS

CD3+, CD4+, CD8+ TILs and MHC1 and MHC2 expression showed significant correlations between primary and recurrent tumor levels (Spearman rho 0.427, 0.533, 0.361, 0.456, 0.526 respectively; P<.0001 each). Paired testing revealed higher CD4+ densities and MHC1 expression in recurrent tumors (Wilcoxon P=.034 and P=.018). There was also a shift towards higher CD3+ TILs levels in recurrent carcinomas when analyzing platinum-sensitive tumors only (Wilcoxon P=.026) and in pairs with recurrent tumor tissue from first relapse only (Wilcoxon P=.031). High MHC2 expression was the only parameter to be significantly linked to prolonged progression-free survival after first relapse (PFS2, log-rank P=.012).

CONCLUSIONS

This is the first study that analyzed the development of TILs density and MHC expression in paired primary and recurrent HGSOC. The level of the antitumoral immune response in recurrent tumors was clearly dependent on the one in the primary tumor. Our data contribute to the understanding of temporal heterogeneity of HGSOC immune microenvironment and have implications for selection of samples for biomarker testing in the setting of immune-targeting therapeutics.

10H-3,6-Diazaphenothiazine induces G2/M phase cell cycle arrest and caspase-dependent apoptosis and inhibits cell invasion of A2780 ovarian carcinoma cells through the regulation of NF-κB and (BIRC6-XIAP) complexes

The asymptomatic properties and high treatment resistance of ovarian cancer result in poor treatment outcomes and high mortality rates. Although the fundamental chemotherapy provides promising anticancer activities, it is associated with severe side effects. The derivative of phenothiazine, namely, 10H-3,6-diazaphenothiazine (PTZ), was synthesized and reported with ideal anticancer effects in a previous paper. In this study, detailed anticancer properties of PTZ was examined on A2780 ovarian cancer cells by investigating the cytotoxicity profiles, mechanism of apoptosis, and cell invasion. Research outcomes revealed PTZ-induced dose-dependent inhibition on A2780 cancer cells (IC₅₀ =0.62 µM), with significant less cytotoxicity toward HEK293 normal kidney cells and H9C2 normal heart cells. Generation of reactive oxygen species (ROS) and polarization of mitochondrial membrane potential (ΔΨm) suggests PTZ-induced cell death through oxidative damage. The RT² Profiler PCR Array on apoptosis pathway demonstrated PTZ-induced apoptosis via intrinsic (mitochondria-dependent) and extrinsic (cell death receptor-dependent) pathway. Inhibition of NF-κB and subsequent inhibition of (BIRC6-XIAP) complex activities reduced the invasion rate of A2780 cancer cells penetrating through the Matrigel™ Invasion Chamber. Lastly, the cell cycle analysis hypothesizes that the compound is cytostatic and significantly arrests cell proliferation at G₂/M phase. Hence, the exploration of the underlying anticancer mechanism of PTZ suggested its usage as promising chemotherapeutic agent.

Radiation Treatment in Women with Ovarian Cancer: Past, Present, and Future

Ovarian cancer is the most lethal of the gynecologic cancers, with 5-year survival rates less than 50%. Most women present with advanced stage disease as the pattern of spread is typically with dissemination of malignancy throughout the peritoneal cavity prior to development of any symptoms. Prior to the advent of platinum-based chemotherapy, radiotherapy was used as adjuvant therapy to sterilize micrometastatic disease. The evolution of radiotherapy is detailed in this review, which establishes radiotherapy as an effective therapy for women with micrometastatic disease in the peritoneal cavity after surgery, ovarian clear cell carcinoma, focal metastatic disease, and for palliation of advanced disease. However, with older techniques, the toxicity of whole abdominal radiotherapy and the advancement of systemic therapies have limited the use of radiotherapy in this disease. With newer radiotherapy techniques, including intensity-modulated radiotherapy (IMRT), stereotactic body radiotherapy (SBRT), and low-dose hyperfractionation in combination with targeted agents, radiotherapy could be reconsidered as part of the standard management for this deadly disease.

Prognostic significance and predictors of the system inflammation score in ovarian clear cell carcinoma

Chronic inflammation is a well-known epidemiologic factor of ovarian clear cell carcinomas (OCCC), but has an uncertain role in prognosis. We developed a systemic inflammation score (SIS) based on preoperative serum albumin and neutrophil-to-lymphocyte ratio (NLR) for predicting progression-free survival (PFS) and overall survival (OS) in OCCC patients. A retrospective review was performed in 155 patients with OCCC undergoing primary debulking and chemotherapy at a single institute between 1995 and 2010. Cox regression models were fitted to analyze the effect of prognostic factors on PFS and OS. Harrell’s concordance index was calculated to assess predictive accuracy. The SIS consisting of serum albumin and NLR was retained as an independent indicator adjusting for traditional clinicopathological features. A high SIS was significantly associated with aggressive tumor behavior, platinum resistance, and served as an independent predictor of reduced PFS (P = 0.006) and OS (P = 0.019). The SIS had a good discrimination ability for the predictive PFS (c-index = 0.712) and OS (c-index = 0.722). We have developed a system inflammation score for predicting prognosis of OCCC patients, which may help stratify patients for postsurgical management.

Ovarian cancer and the immune system

Short communication in response to the review of Turner et al. entitled “Ovarian cancer and the immune system - the role of targeted therapies” published in Gynecological Oncology. We believe systemic immune parameters might be a good alternative to tumor biopsy to gain insight in the immunological background of ovarian cancer.

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The immune system is an important player in ovarian cancer behaviour.

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Intratumoral studies of the immune system show an overwhelming immunosuppression.

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The immune signature in the blood can be important as a new biomarker.

Preoperative Monocyte-to-Lymphocyte Ratio in Peripheral Blood Predicts Stages, Metastasis, and Histological Grades in Patients with Ovarian Cancer

PURPOSE: The monocyte-to-lymphocyte ratio (MLR) has been shown to be associated with the prognosis of various solid tumors. This study sought to evaluate the important value of the MLR in ovarian cancer patients. METHODS: A total of 133 ovarian cancer patients and 43 normal controls were retrospectively reviewed. The patients' demographics were analyzed along with clinical and pathologic data. The counts of peripheral neutrophils, lymphocytes, monocytes, and platelets were collected and used to calculate the MLR, neutrophil-to-lymphocyte ratio (NLR). and platelet-to-lymphocyte ratio (PLR). The optimal cutoff value of the MLR was determined by using receiver operating characteristic curve analysis. We compared the MLR, NLR, and PLR between ovarian cancer and normal control patients and among patients with different stages and different grades, as well as between patients with lymph node metastasis and non–lymph node metastasis. We then investigated the value of the MLR in predicting the stage, grade, and lymph node positivity by using logistic regression. The impact of the MLR on overall survival (OS) was calculated by Kaplan-Meier method and compared by log-rank test. RESULTS: Statistically significant differences in the MLR were observed between ovarian cancer patients and normal controls. However, no difference was found for the NLR and PLR. Highly significant differences in the MLR were found among patients with different stages (stage I-II and stage III-IV), grades (G1 and >G1), and lymph node metastasis status. The MLR was a significant and independent risk factor for lymph node metastasis, as determined by logistic regression. The optimal cutoff value of the MLR was 0.23. We also classified the data according to tumor markers (CA125, CA199, HE4, AFP, and CEA) and conventional coagulation parameters (International Normalized Ratio [INR] and fibrinogen). Highly significant differences in CA125, CA199, HE4, INR, fibrinogen levels, and lactate dehydrogenase were found between the low-MLR group (MLR ≤ 0.23) and the high-MLR group (MLR > 0.23). Correspondingly, dramatic differences were observed between the two groups in OS. CONCLUSION: Our results show that the peripheral blood MLR before surgery could be a significant predictor of advanced stages, advanced pathologic grades, and positive lymphatic metastasis in ovarian cancer patients.