Who are the long-term survivors of high grade serous ovarian cancer?

The Long-Term Prognostic Significance of Circulating Tumor Cells in Ovarian Cancer-A Study of the OVCAD Consortium

INTRODUCTION

We previously reported the prognostic impact of circulating tumor cells (CTCs) in a multicenter study on minimal residual disease in primary ovarian cancer. With additional follow-up data, we evaluated the combined CTC approach (CTCs^combo), in particular for the patients who had survived more than five years.

MATERIAL AND METHODS

Blood samples taken at baseline and six months after adjuvant treatment (follow-up) were assessed by quantitative PCR (qPCR) measuring PPIC transcripts and immunofluorescent staining (IF). A positive result with either IF or qPCR was classified as CTC^combo-positive. Further, PPIC was assessed in the primary tumor tissue.

RESULTS

The concordance of IF and qPCR was 65% at baseline and 83% after treatment. Results showed that 50.5% of the baseline and 29.5% of the follow-up samples were CTC^combo-positive. CTCs^combo after treatment were associated with increased mortality after adjusting for FIGO stage (HR 2.574, 95% CI: 1.227-5.398, p = 0.012), a higher risk of recurrence after adjusting for peritoneal carcinosis (HR 4.068, 95% CI: 1.948-8.498, p < 0.001), and increased mortality after five survived years.

DISCUSSION

The two-sided analytical approach revealed CTC subpopulations associated with ovarian cancer progression and may illuminate a potential treatment-related shift in molecular phenotypes. That approach can identify patients who have elevated risk of recurrence and death due to ovarian cancer and who may require risk-adapted treatment strategies.

Radiomics Analysis of PET and CT Components of 18F-FDG PET/CT Imaging for Prediction of Progression-Free Survival in Advanced High-Grade Serous Ovarian Cancer

Objective

To investigate radiomics features extracted from PET and CT components of ¹⁸F-FDG PET/CT images integrating clinical factors and metabolic parameters of PET to predict progression-free survival (PFS) in advanced high-grade serous ovarian cancer (HGSOC).

Methods

A total of 261 patients were finally enrolled in this study and randomly divided into training (n=182) and validation cohorts (n=79). The data of clinical features and metabolic parameters of PET were reviewed from hospital information system(HIS). All volumes of interest (VOIs) of PET/CT images were semi-automatically segmented with a threshold of 42% of maximal standard uptake value (SUVmax) in PET images. A total of 1700 (850×2) radiomics features were separately extracted from PET and CT components of PET/CT images. Then two radiomics signatures (RSs) were constructed by the least absolute shrinkage and selection operator (LASSO) method. The RSs of PET (PET_RS) and CT components(CT_RS) were separately divided into low and high RS groups according to the optimum cutoff value. The potential associations between RSs with PFS were assessed in training and validation cohorts based on the Log-rank test. Clinical features and metabolic parameters of PET images (PET_MP) with P-value <0.05 in univariate and multivariate Cox regression were combined with PET_RS and CT_RS to develop prediction nomograms (Clinical, Clinical+ PET_MP, Clinical+ PET_RS, Clinical+ CT_RS, Clinical+ PET_MP + PET_RS, Clinical+ PET_MP + CT_RS) by using multivariate Cox regression. The concordance index (C-index), calibration curve, and net reclassification improvement (NRI) was applied to evaluate the predictive performance of nomograms in training and validation cohorts.

Results

In univariate Cox regression analysis, six clinical features were significantly associated with PFS. Ten PET radiomics features were selected by LASSO to construct PET_RS, and 1 CT radiomics features to construct CT_RS. PET_RS and CT_RS was significantly associated with PFS both in training (P <0.00 for both RSs) and validation cohorts (P=0.01 for both RSs). Because there was no PET_MP significantly associated with PFS in training cohorts. Only three models were constructed by 4 clinical features with P-value <0.05 in multivariate Cox regression and RSs (Clinical, Clinical+ PET_RS, Clinical+ CT_RS). Clinical+ PET_RS model showed higher prognostic performance than other models in training cohort (C-index=0.70, 95% CI 0.68-0.72) and validation cohort (C-index=0.70, 95% CI 0.66-0.74). Calibration curves of each model for prediction of 1-, 3-year PFS indicated Clinical +PET_RS model showed excellent agreements between estimated and the observed 1-, 3-outcomes. Compared to the basic clinical model, Clinical+ PET_MS model resulted in greater improvement in predictive performance in the validation cohort.

Conclusion

PET_RS can improve diagnostic accuracy and provide complementary prognostic information compared with the use of clinical factors alone or combined with CT_RS. The newly developed radiomics nomogram is an effective tool to predict PFS for patients with advanced HGSOC.

BRCA1 Expression by Immunohistochemistry and Prognosis in Ovarian Cancer: A Systematic Review and Meta-Analysis

BACKGROUND

Homologous recombination deficiencies are associated with increased platinum sensitivity and potential response to poly (ADP-ribose) polymerase inhibitors in epithelial ovarian cancer. As an alternative to germline testing or somatic tumor sequencing, BRCA1 deficiency can be detected by immunohistochemistry and might predict homologous recombination deficiencies.

OBJECTIVE

This study aimed to assess the association between BRCA1 expression by immunohistochemistry and the prognosis of patients with epithelial ovarian cancer.

METHODS

We conducted a systematic review and meta-analysis following the Preferred Reporting Items for Systematic reviews and Meta-Analyses statement. We searched PubMed, EMBASE, Web of Science, and Scopus databases through July 2019. Reference lists of selected articles were screened for further studies. We conducted qualitative synthesis and meta-analyses of hazard ratios for overall survival and progression-free survival.

RESULTS

Of 41 studies of BRCA1 expression using immunohistochemistry, 18 evaluated the association of BRCA1 expression with patient survival (2738 cases). The loss of BRCA1 expression was associated with improved overall survival (hazard ratio = 0.67, 95% confidence interval 0.57-0.77) and progression-free survival (hazard ratio = 0.70, 95% confidence interval 0.58-0.84).

CONCLUSIONS

Negative BRCA1 expression assessed by immunohistochemistry was associated with a better prognosis in epithelial ovarian cancer.

Prognostic impact of socioeconomic status on long-term survival of non-localized epithelial ovarian cancer ꟷ The Extreme study

OBJECTIVE

To examine the influence of socioeconomic status (SES) on long-term survival of non-localized ovarian cancer.

METHODS

All women in Denmark with a first diagnosis of non-localized epithelial ovarian cancer 1982-2007 were identified in the Cancer Registry and/or the Pathology Registry and followed up until December 2017. The survival probability was estimated after respectively 5 and 10 years, using so-called pseudo observations, and analyzed according to education, income, and marital status defined from nationwide registries.

RESULTS

The study cohort included 6486 women, and the estimated 5- and 10-year survival probabilities were 21.4% and 12.7%, respectively. Compared to women with short education, the 5-year survival probability was 7% higher for women with medium (relative survival probability = 1.07, 95% CI: 0.97, 1.19) and long education (relative survival probability = 1.07, 95% CI: 0.93, 1.24). Compared with married women, the 5-year survival probability for divorced women/widower was slightly lower (0.85, 95% CI: 0.69, 1.04) and for unmarried women slightly higher (1.08, 95% CI: 0.94, 1.23). Finally, the probability of being alive 5 years after diagnosis was 1.09 times higher (95% CI: 0.95, 1.24) for medium-income women and 1.23 times higher (95% CI: 1.08, 1.41) for high-income women compared with low-income women. Similar patterns were observed for 10-year survival.

CONCLUSIONS

Non-localized ovarian cancer patients have a poor prognosis. Our data suggest that among Danish women with advanced ovarian cancer, higher personal income is associated with slightly higher probability of long-term survival, whereas education and marital status did not affect the probability of long-term survival.

Impact of clinical factors and surgical outcome on long-term survival in high-grade serous ovarian cancer: a multicenter analysis

INTRODUCTION

Long-term survivors of ovarian cancer are a unique group of patients in whom prognostic factors for long-term survival have been poorly described. Such factors may provide information for a more personalized therapeutic approach. The objective of this study is to determine further characteristics of long-term survivors with high-grade serous ovarian cancer.

METHODS

Long-term survivors were defined as patients living longer than 8 years after first diagnosis and were recruited within seven high volume centers across Europe from November 1988 to November 2008. The control group included patients with high-grade serous ovarian cancer with less than 5 years' survival identified from the systematic 'Tumorbank ovarian cancer' database. A subanalysis of Charité patients only was performed separately for in-depth analysis of tumor dissemination. Propensity score matching with nearest-neighbor caliper width was used to match long-term survivors and the control group regarding age, FIGO stage, and residual tumor.

RESULTS

A total of 276 patients with high-grade serous ovarian cancer were included, divided into 131 long-term survivors and 145 control group patients. After propensity score matching and multivariable adjustment, platinum sensitivity (p=0.002) was an independent favorable prognostic factor whereas recurrence (p<0.001) and ascites (p=0.021) were independent detrimental predictors for long-term survival. Significantly more long-term survivors tested positive for mutation in the BRCA1 gene than the BRCA2 gene (p=0.016). Intraoperatively, these patients had less tumor involvement of the upper abdomen at initial surgery (p=0.024). Complexity of surgery and surgical techniques were similar in both cohorts.

CONCLUSION

Platinum sensitivity constitutes a favorable factor for long-term survival whereas tumor involvement of the upper abdomen, ascites, and recurrence have a negative impact. Based on clinical estimation, long-term survival is associated with combinations of clinical, surgical, and molecular factors.

The Exceptional Responders Initiative: Feasibility of a National Cancer Institute Pilot Study

BACKGROUND

Tumor molecular profiling from patients experiencing exceptional responses to systemic therapy may provide insights into cancer biology and improve treatment tailoring. This pilot study evaluates the feasibility of identifying exceptional responders retrospectively, obtaining pre-exceptional response treatment tumor tissues, and analyzing them with state-of-the-art molecular analysis tools to identify potential molecular explanations for responses.

METHODS

Exceptional response was defined as partial (PR) or complete (CR) response to a systemic treatment with population PR or CR rate less than 10% or an unusually long response (eg, duration >3 times published median). Cases proposed by patients' clinicians were reviewed by clinical and translational experts. Tumor and normal tissue (if possible) were profiled with whole exome sequencing and, if possible, targeted deep sequencing, RNA sequencing, methylation arrays, and immunohistochemistry. Potential germline mutations were tracked for relevance to disease.

RESULTS

Cases reflected a variety of tumors and standard and investigational treatments. Of 520 cases, 476 (91.5%) were accepted for further review, and 222 of 476 (46.6%) proposed cases met requirements as exceptional responders. Clinical data were obtained from 168 of 222 cases (75.7%). Tumor was provided from 130 of 168 cases (77.4%). Of 117 of the 130 (90.0%) cases with sufficient nucleic acids, 109 (93.2%) were successfully analyzed; 6 patients had potentially actionable germline mutations.

CONCLUSION

Exceptional responses occur with standard and investigational treatment. Retrospective identification of exceptional responders, accessioning, and sequencing of pretreatment archived tissue is feasible. Data from molecular analyses of tumors, particularly when combining results from patients who received similar treatments, may elucidate molecular bases for exceptional responses.

Protein anabolism is key to long-term survival in high-grade serous ovarian cancer

This study aimed to identify the biological processes associated with long-term survival in high-grade serous ovarian cancer (HGSOC). HGSOC cases obtained from The Cancer Genome Atlas Ovarian Cancer (TCGA-OV) database were divided into long-term survivors (LTS) and normal-term survivors (NTS) based on survival cutoffs defined by the HGSOC cohort in the SEER database. Differentially expressed genes (DEGs) were screened using the generalized linear modeling (GLM) method. Gene Ontology (GO) functional and KEGG pathway enrichment analyses were performed using DAVID Bioinformatics Resources. DEG-related protein-protein interactions (PPI) were extracted from the STRING database and hub genes were identified using CytoHubba in the Cytoscape program. In total, 157 DEGs, including 155 upregulated and 2 downregulated genes, were identified. Upregulated genes were statistically enriched in 80 GO terms and 11 KEGG pathways related to energy and substrate metabolism, such as protein absorption, digestion, and metabolism as well as signaling pathways, including chromatin silencing, regulation of ERK1 and ERK2 cascade, and regulation of MAPKKK. ALB and POMC were the common hub genes. These findings reveal that protein anabolism is crucial to long-term survival, regulated by activation of the MAPK/ERK signaling pathway and chromatin silencing. Comprehensive understanding of the molecular mechanisms via further exploration may contribute toward an effective treatment for ovarian cancer.

Cost-effectiveness of olaparib as a maintenance treatment for women with newly diagnosed advanced ovarian cancer and BRCA1/2 mutations in the United States

OBJECTIVE

This study evaluated the cost-effectiveness of olaparib monotherapy in the first-line maintenance setting vs. surveillance in women with newly diagnosed advanced ovarian cancer and a BRCA1/2 mutation from a US third-party payer perspective.

METHODS

A three-state (progression free, progressed disease, and death) partitioned survival model over a 50-year lifetime horizon was developed. Piecewise models were applied to data from the phase III trial SOLO1 to extrapolate survival outcomes. Health state utilities and adverse event disutilities were obtained from literature and SOLO1. Treatment costs, adverse event costs, and medical costs associated with health states were obtained from publicly available databases, SOLO1, and real-world data. Time on treatment was estimated using the data from SOLO1. Incremental costs per quality-adjusted life year (QALY) and life year (LY) gained were estimated. One-way deterministic and probabilistic sensitivity analyses were conducted.

RESULTS

Over a lifetime horizon, olaparib was associated with an additional 3.63 LYs and 2.93 QALYs, and an incremental total cost of $152,545 vs. surveillance. Incremental cost per LY gained and per QALY gained for olaparib were $42,032 and $51,986, respectively. The incremental cost-effectiveness ratios remained below $100,000 across a range of inputs and scenarios. In the PSA, the probability of olaparib being cost-effective at a $100,000 per QALY threshold was 99%.

CONCLUSIONS

Compared to surveillance, olaparib increases both the LYs and QALYs of women with newly diagnosed advanced ovarian cancer and with a germline or somatic BRCA mutation. Olaparib offers a cost-effective maintenance option for these women from a US third-party payer perspective.

Integrative network analysis identifies potential targets and drugs for ovarian cancer

BACKGROUND

Though accounts for 2.5% of all cancers in female, the death rate of ovarian cancer is high, which is the fifth leading cause of cancer death (5% of all cancer death) in female. The 5-year survival rate of ovarian cancer is less than 50%. The oncogenic molecular signaling of ovarian cancer are complicated and remain unclear, and there is a lack of effective targeted therapies for ovarian cancer treatment.

METHODS

In this study, we propose to investigate activated signaling pathways of individual ovarian cancer patients and sub-groups; and identify potential targets and drugs that are able to disrupt the activated signaling pathways. Specifically, we first identify the up-regulated genes of individual cancer patients using Markov chain Monte Carlo (MCMC), and then identify the potential activated transcription factors. After dividing ovarian cancer patients into several sub-groups sharing common transcription factors using K-modes method, we uncover the up-stream signaling pathways of activated transcription factors in each sub-group. Finally, we mapped all FDA approved drugs targeting on the upstream signaling.

RESULTS

The 427 ovarian cancer samples were divided into 3 sub-groups (with 100, 172, 155 samples respectively) based on the activated TFs (with 14, 25, 26 activated TFs respectively). Multiple up-stream signaling pathways, e.g., MYC, WNT, PDGFRA (RTK), PI3K, AKT TP53, and MTOR, are uncovered to activate the discovered TFs. In addition, 66 FDA approved drugs were identified targeting on the uncovered core signaling pathways. Forty-four drugs had been reported in ovarian cancer related reports. The signaling diversity and heterogeneity can be potential therapeutic targets for drug combination discovery.

CONCLUSIONS

The proposed integrative network analysis could uncover potential core signaling pathways, targets and drugs for ovarian cancer treatment.

Epithelial/mesenchymal heterogeneity of high-grade serous ovarian carcinoma samples correlates with miRNA let-7 levels and predicts tumor growth and metastasis

Patient‐derived samples present an advantage over current cell line models of high‐grade serous ovarian cancer (HGSOC) that are not always reliable and phenotypically faithful models of in vivo HGSOC. To improve upon cell line models of HGSOC, we set out to characterize a panel of patient‐derived cells and determine their epithelial and mesenchymal characteristics. We analyzed RNA and protein expression levels in patient‐derived xenograft (PDX) models of HGSOC, and functionally characterized these models using flow cytometry, wound healing assays, invasion assays, and spheroid cultures. Besides in vitro work, we also evaluated the growth characteristics of PDX in vivo (orthotopic PDX). We found that all samples had hybrid characteristics, covering a spectrum from an epithelial‐to‐mesenchymal state. Samples with a stronger epithelial phenotype were more active in self‐renewal assays and more tumorigenic in orthotopic xenograft models as compared to samples with a stronger mesenchymal phenotype, which were more migratory and invasive. Additionally, we observed an inverse association between microRNA let‐7 (lethal‐7) expression and stemness, consistent with the loss of let‐7 being an important component of the cancer stem cell phenotype. We observed that lower let‐7 levels were associated with the epithelial state and a lower epithelial mesenchymal transition (EMT) score, more efficient spheroid and tumor formation, and increased sensitivity to platinum‐based chemotherapy. Surprisingly, in these HGSOC cells, stemness could be dissociated from invasiveness: Cells with lower let‐7 levels were more tumorigenic, but less migratory, and with a lower EMT score, than those with higher let‐7 levels. We conclude that let‐7 expression and epithelial/mesenchymal state are valuable predictors of HGSOC proliferation, in vitro self‐renewal, and tumor burden in vivo.

Long term survival outcomes of stage I mucinous ovarian cancer - A clinical calculator predictive of chemotherapy benefit

OBJECTIVES

To determine the long-term potential benefit of adjuvant chemotherapy in subgroups of high-risk stage I mucinous ovarian cancer patients using a predictive scoring algorithm.

METHODS

Data were collected from the National Cancer Database from 2004 to 2014. Based on demographic and surgical characteristics, a novel 10-year survival prognostic scoring system was developed using Cox regression.

RESULTS

There were 2041 eligible patients with stage I mucinous ovarian cancer including 1362 (67%) with stage IA/IB disease, 598 (29%) with stage IC disease, and 81 (4%) with stage I disease not otherwise specified. Median age was 52 with a range of 13-90 years old. 737 (36%) patients were treated with adjuvant chemotherapy. Adjuvant chemotherapy was more common in patients with stage IC relative to stage IA/IB disease (69% vs. 21%, P < 0.001) or with poorly-differentiated relative to well-differentiated tumors (69% vs. 23%, P < 0.001). Unadjusted 10-year survival was 81% relative to 79% for patients treated with vs. without chemotherapy, respectively (P = 0.46). Patients were predicted to exhibit a low- or a high-risk of death using a multivariate Cox regression model with age, stage, grade, lymphovascular space invasion and ascites. Risk of death without vs. with adjuvant chemotherapy was similar in low-risk patients (88% vs. 84%; HR = 0.80, 95%CI = 0.56-1.15, P = 0.23) and worse in high-risk patients (51% vs. 74%; HR = 1.58, 95%CI: 1.05-2.38, P = 0.03) with stage I mucinous ovarian cancer.

CONCLUSIONS

A predictive scoring algorithm may provide prognostic information on long-term survival and identify high-risk stage I mucinous ovarian cancer patients who might achieve a survival benefit from adjuvant chemotherapy.

Quality of advanced ovarian cancer surgery: A French assessment of ESGO quality indicators

OBJECTIVES

In 2016, the European Society of Gynecology Oncology (ESGO) published indicators defining the quality of surgical management of advanced ovarian cancer. The objective of the study was to assess the quality of ovarian cancer patient management in regional centers authorized for gynecological cancer, based on the ESGO list of quality indicators.

METHODS

A multicenter retrospective observational cohort study was conducted from January 1 to June 30, 2016. The following quality indicators 1 "rate of complete surgical resection", 4 "center participating in clinical trials in gynecologic oncology", 5 "treatment planned and reviewed at a multidisciplinary team meeting", 6 "required preoperative workup", 8 "minimum required elements in operative reports" and 9 "minimum required elements in pathology reports" were selected.

RESULTS

91 patients were evaluated in 16 centers. The required preoperative workup was incomplete in 25% of cases. Treatment was not planned at a multidisciplinary team meeting for 24%. An evaluation score of peritoneal involvement was included in 40% of the operative reports and the quality of surgical resection was reported in 72%. Primary surgery was most often performed in a peripheral hospital (48%), interval surgery in a private center (37%), and closure surgery in a regional cancer center (43%). No institution respected the six quality indicators evaluated. One regional cancer center respected five items and two private centers did not respect any.

CONCLUSION

Whilst the ESGO quality indicators provide objective, validated and evaluable support which centers can use to improve quality of care, we observed heterogeneous practices amongst the centers evaluated.

Conditional Probability of Survival and Prognostic Factors in Long-Term Survivors of High-Grade Serous Ovarian Cancer

Objective: High-grade serous ovarian cancers (HGSOC) are heterogeneous, often diagnosed at an advanced stage, and associated with poor overall survival (OS, 39% at five years). There are few data about the prognostic factors of late relapses in HGSOC patients who survived ≥five years, long-term survivors (LTS). The aim of our study is to assess the probability of survival according to the already survived time from diagnosis. Methods: Data from HGSOC patients treated between 1995 and 2016 were retrospectively collected to estimate the conditional probability of survival (CPS), probability of surviving Y years after diagnosis when the patient had already survived X years, and to determine the LTS prognostic factors. The primary endpoint was OS. Results: 404 patients were included; 120 of them were LTS. Patients were aged 61 years (range: 20–89), WHO performance status 0–1 in 86.9% and 2 in 13.1%, and Fédération Internationale de Gynécologie et d’Obstétrique (FIGO) staging III and IV in 82.7% and 17.3% patients. Breast cancer (BRCA) status was available in 116 patients (33% mutated), including 58 LTS (36% mutated). No macroscopic residual disease was observed in 58.4% patients. First-line platinum-based chemotherapy plus paclitaxel was administered in 80.4% of patients (median: six cycles (range: 1–14)). After a 9 point 3-year follow-up, median OS was four years (95% CI: 3.6–4.5). The CPS at five years after surviving one year was 42.8% (95% CI: 35.3–48.3); it increased to 81.7% (95% CI: 75.5–87.8) after four survived years. Progression-free interval>18 months was the only LTS prognostic factor in the multivariable analysis (hazard ratio (HR) = 0.23; 95% CI: 0.13–0.40; p < 0.001). Conclusion: The CPS provided relevant and encouraging clinical information on the life expectancy of HGSOC patients who already survived a period of time after diagnosis. LTS prognostic factors are useful for clinicians and patients.

The untapped potential of ascites in ovarian cancer research and treatment

The build-up of fluid in the peritoneal cavity-ascites-is a hallmark of ovarian cancer, the most lethal of all gynaecological malignancies. This remarkable fluid, which contains a variety of cellular and acellular components, is known to contribute to patient morbidity and mortality by facilitating metastasis and contributing to chemoresistance, but remains largely under-researched. In this review, we will critically analyse the evidence associating ascites with metastasis and chemoresistance in ovarian cancer and provide an update on research in the field. We will argue the case for ascites as a unique and accessible substrate for tracking tumour progression and for translational research that will enhance our understanding of this cancer and lead to improvements in patient outcomes.

CtBP determines ovarian cancer cell fate through repression of death receptors

C-terminal binding protein 2 (CtBP2) is elevated in epithelial ovarian cancer, especially in the aggressive and highly lethal subtype, high-grade serous ovarian cancer (HGSOC). However, whether HGSOC tumor progression is dependent on CtBP2 or its paralog CtBP1, is not well understood. Here we report that CtBP1/2 repress HGSOC cell apoptosis through silencing of death receptors (DRs) 4/5. CtBP1 or 2 knockdown upregulated DR4/5 expression, and triggered autonomous apoptosis via caspase 8 activation, but dependent on cell-type context. Activation of DR4/5 by CtBP1/2 loss also sensitized HGSOC cell susceptibility to the proapoptotic DR4/5 ligand TRAIL. Consistent with its function as transcription corepressor, CtBP1/2 bound to the promoter regions of DR4/5 and repressed DR4/5 expression, presumably through recruitment to a repressive transcription regulatory complex. We also found that CtBP1 and 2 were both required for repression of DR4/5. Collectively, this study identifies CtBP1 and 2 as potent repressors of DR4/5 expression and activity, and supports the targeting of CtBP as a promising therapeutic strategy for HGSOC.

Combination Treatment with an Antibody-Drug Conjugate (A1mcMMAF) Targeting the Oncofetal Glycoprotein 5T4 and Carboplatin Improves Survival in a Xenograft Model of Ovarian Cancer

Background

Recurrence occurs in over 75% of women with epithelial ovarian cancer despite optimal treatment. Selectively killing tumour cells thought to initiate relapse using an antibody–drug conjugate could prolong progression-free survival and offer an improved side-effect profile. A1mcMMAF is an antibody–drug conjugate designed to target cells expressing the tumour-associated antigen 5T4. It has shown to be efficacious in various cell line models and have a greater impact when combined with routine chemotherapeutic regimes.

Objectives

This study aims to explore the potential for the use of a 5T4 antibody–drug conjugate in women with ovarian cancer both as a monotherapy and in combination with platinum-based chemotherapy.

Methods

Immunohistochemical analysis was used to assess 5T4 expression in tumours from patients with ovarian cancer. Effectiveness of A1mcMMAF therapy as a single agent and in combination with carboplatin was assessed in vitro in the ovarian cancer cell line SKOV3 and confirmed in vivo using a serial bioluminescence assay in a SKOV3 xenograft model of ovarian cancer.

Results

5T4 is confirmed as suitably expressed in epithelial ovarian cancers prior to adjuvant therapy and is an independent predictor of poor survival. A1mcMMAF showed specific activity, both in vitro and in vivo, against SKOV3 ovarian cancer cells. When used in combination with carboplatin, in vivo tumour growth was inhibited resulting in prolonged survival in a SKOV3 xenograft model.

Conclusions

These data support further investigation of A1mcMMAF in combination with platinum-based chemotherapy in ovarian and other cancer treatments.

Electronic supplementary material

The online version of this article (10.1007/s11523-019-00650-8) contains supplementary material, which is available to authorized users.

Flow-induced Shear Stress Confers Resistance to Carboplatin in an Adherent Three-Dimensional Model for Ovarian Cancer: A Role for EGFR-Targeted Photoimmunotherapy Informed by Physical Stress

A key reason for the persistently grim statistics associated with metastatic ovarian cancer is resistance to conventional agents, including platinum-based chemotherapies. A major source of treatment failure is the high degree of genetic and molecular heterogeneity, which results from significant underlying genomic instability, as well as stromal and physical cues in the microenvironment. Ovarian cancer commonly disseminates via transcoelomic routes to distant sites, which is associated with the frequent production of malignant ascites, as well as the poorest prognosis. In addition to providing a cell and protein-rich environment for cancer growth and progression, ascitic fluid also confers physical stress on tumors. An understudied area in ovarian cancer research is the impact of fluid shear stress on treatment failure. Here, we investigate the effect of fluid shear stress on response to platinum-based chemotherapy and the modulation of molecular pathways associated with aggressive disease in a perfusion model for adherent 3D ovarian cancer nodules. Resistance to carboplatin is observed under flow with a concomitant increase in the expression and activation of the epidermal growth factor receptor (EGFR) as well as downstream signaling members mitogen-activated protein kinase/extracellular signal-regulated kinase (MEK) and extracellular signal-regulated kinase (ERK). The uptake of platinum by the 3D ovarian cancer nodules was significantly higher in flow cultures compared to static cultures. A downregulation of phospho-focal adhesion kinase (p-FAK), vinculin, and phospho-paxillin was observed following carboplatin treatment in both flow and static cultures. Interestingly, low-dose anti-EGFR photoimmunotherapy (PIT), a targeted photochemical modality, was found to be equally effective in ovarian tumors grown under flow and static conditions. These findings highlight the need to further develop PIT-based combinations that target the EGFR, and sensitize ovarian cancers to chemotherapy in the context of flow-induced shear stress.

RNA Immune Signatures from Pan-Cancer Analysis Are Prognostic for High-Grade Serous Ovarian Cancer and Other Female Cancers

Immune cell infiltrates within the tumor microenvironment can influence treatment response and outcome in several cancers. In this study, we developed RNA-based immune signatures from pan-cancer analysis that could serve as potential markers across tumor types and tested them for association with outcome in high-grade serous ovarian cancer (HGSOC) and other female cancers. Pan-cancer RNA-Seq cluster analysis of immune-related gene expression profiles in The Cancer Genome Atlas (TCGA) from 29 different solid tumors (4446 specimens) identified distinct but concordant gene signatures. Among these immune signatures, Cytotoxic Lymphocyte Immune Signature (CLIS), T-cell trafficking (TCT), and the TCT to M2 tumor-associated macrophage (M2TAM) ratio (TCT:M2TAM) were significantly (p < 0.05) associated with overall survival (OS), using multivariable Cox proportional hazards regression models, in a discovery cohort and two independent validation cohorts of HGSOC patients. Notably, the TCT:M2TAM ratio was highly significant (p ≤ 0.000001) in two HGSOC cohorts. Immune signatures were also significant (p < 0.05) in the presence of tumor cytoreduction, BRCA1/2 mutation, and COL2A1 expression. Importantly, the CLIS and TCT signatures were also validated for prognostic significance (p < 0.05) in TCGA cohorts for endometrial and high tumor mutational burden (Hi-TMB) breast cancer. These immune signatures also have the potential for being predictive in other cancers and for patients following different treatment strategies.

Prognostic Significance of Systematic Lymphadenectomy in Patients With Optimally Debulked Advanced Ovarian Cancer: A Meta-Analysis

Background: The effect of systematic lymphadenectomy (SL) on survival in patients with optimally debulked advanced ovarian cancer remains unclear. We evaluated the therapeutic value of SL in advanced ovarian cancer patients who underwent primary optimal debulking surgery.

Methods: A meta-analysis was carried out using articles retrieved from the PubMed, Embase, and Cochrane databases. Overall survival (OS) and progression-free survival (PFS) were compared between patients who underwent SL and those who underwent unsystematic lymphadenectomy (USL).

Results: Seven studies that included 2,425 patients with advanced ovarian cancer were included in the meta-analysis. The overall analyses indicated significantly improved OS [hazard ratio (HR) = 0.64, 95% confidence interval (CI): 0.49–0.84, P < 0.01] but not PFS (HR = 0.89, 95% CI: 0.69–1.15, P = 0.38) in patients who underwent SL compared to those who underwent USL. Subgroup analyses based on study type, study quality, total numbers of patients, and International Federation of Gynecology and Obstetrics (FIGO) stage provided similar results. However, subgroup analysis of patients with no residual tumor revealed that SL was not associated with improved OS (HR = 0.81, 95% CI: 0.66–1.00, P = 0.05) or PFS (HR = 1.09, 95% CI: 0.91–1.30, P = 0.33).

Conclusions: In patients with optimally debulked advanced ovarian cancer, SL may improve OS but not PFS. However, SL does not provide a survival advantage when macroscopically complete resection of all visible tumors is achieved.

Predictors of survival trajectories among women with epithelial ovarian cancer

OBJECTIVE

Although ovarian cancer is a deadly disease, approximately a third of women survive ≥9 years after diagnosis. The factors associated with achieving long-term survival are not well understood. In this study, data from the Surveillance, Epidemiology, and End Results (SEER) program were used to determine predictors of survival trajectories among women with epithelial ovarian cancer and across histotype (high-grade serous carcinoma (HGSC) and non-HGSC).

METHODS

Data on 35,868 women diagnosed with epithelial ovarian cancer in 2004-2016 were extracted from SEER. Extended Cox proportional hazards regression was used to estimate overall and histotype-specific associations between patient and tumor characteristics and all-cause mortality within each survival time (t) interval (t < 3, 3 ≤ t < 6, 6 ≤ t < 9, and 9 ≤ t < 13 years).

RESULTS

Age at diagnosis, marital status, race/ethnicity, stage, and surgery were more strongly associated with mortality in the short-term survival period, and these associations waned with increasing survival time. Exceptions to this pattern were age >70 years at diagnosis, where a high risk of mortality was observed in both the t < 3 and t ≥ 9 year time periods, and non-Hispanic Asian/Pacific Islanders, where a more pronounced inverse association with mortality was observed in t ≥ 9 years after diagnosis. Similar associations were observed for HGSC, although the waning effect was not apparent for most characteristics. Mortality associations for non-HGSC were more pronounced for stage and race/ethnicity, primarily for non-Hispanic Asian/Pacific Islanders.

CONCLUSIONS

Most patient and tumor characteristics were more strongly associated with mortality in the years following diagnosis, but have declining impact with increasing survival time. Given this waning effect, it is critical to identify factors impacting risk of mortality as ovarian cancer patients advance through the survival trajectory.

FXYD5 (Dysadherin) upregulation predicts shorter survival and reveals platinum resistance in high-grade serous ovarian cancer patients

BACKGROUND

High-grade serous ovarian carcinoma (HGSOC) is generally associated with a very dismal prognosis. Nevertheless, patients with similar clinicopathological characteristics can have markedly different clinical outcomes. Our aim was the identification of novel molecular determinants influencing survival.

METHODS

Gene expression profiles of extreme HGSOC survivors (training set) were obtained by microarray. Differentially expressed genes (DEGs) and enriched signalling pathways were determined. A prognostic signature was generated and validated on curatedOvarianData database through a meta-analysis approach. The best prognostic biomarker from the signature was confirmed by RT-qPCR and by immunohistochemistry on an independent validation set. Cox regression model was chosen for survival analysis.

RESULTS

Eighty DEGs and the extracellular matrix-receptor (ECM-receptor) interaction pathway were associated to extreme survival. A 10-gene prognostic signature able to correctly classify patients with 98% of accuracy was identified. By an 'in-silico' meta-analysis, overexpression of FXYD domain-containing ion transport regulator 5 (FXYD5), also known as dysadherin, was confirmed in HGSOC short-term survivors compared to long-term ones. Its prognostic and predictive power was then successfully validated, both at mRNA and protein level, first on training than on validation sample set.

CONCLUSION

We demonstrated the possible involvement of FXYD5 and ECM-receptor interaction signal pathway in HCSOC survival and prognosis.

High EMSY expression defines a BRCA-like subgroup of high-grade serous ovarian carcinoma with prolonged survival and hypersensitivity to platinum

BACKGROUND

Approximately half of high-grade serous ovarian carcinomas (HGSOCs) demonstrate homologous recombination repair (HR) pathway defects, resulting in a distinct clinical phenotype comprising hypersensitivity to platinum, superior clinical outcome, and greater sensitivity to poly(adenosine diphosphate-ribose) polymerase (PARP) inhibitors. EMSY, which is known to be amplified in breast and ovarian cancers, encodes a protein reported to bind and inactivate BRCA2. Thus, EMSY overexpression may mimic BRCA2 mutation, resulting in HR deficiency. However, to our knowledge, the phenotypic consequences of EMSY overexpression in HGSOC patients has not been explored.

METHODS

Here we investigate the impact of EMSY expression on clinical outcome and sensitivity to platinum-based chemotherapy using available data from transcriptomically characterized HGSOC cohorts.

RESULTS

High EMSY expression was associated with better clinical outcome in a cohort of 265 patients with HGSOC from Edinburgh (overall survival multivariable hazard ratio, 0.58 [95% CI, 0.38-0.88; P = .011] and progression-free survival multivariable hazard ratio, 0.62 [95% CI, 0.40-0.96; P = .030]). Superior outcome also was demonstrated in the Medical Research Council ICON7 clinical trial and multiple publicly available data sets. Patients within the Edinburgh cohort who had high EMSY expression were found to demonstrate greater rates of complete response to multiple platinum-containing chemotherapy regimens (radiological complete response rate of 44.4% vs 12.5% at second exposure; P = .035) and corresponding prolonged time to disease progression (median, 151.5 days vs 60.5 days after third platinum exposure; P = .004).

CONCLUSIONS

Patients with HGSOCs demonstrating high EMSY expression appear to experience prolonged survival and greater platinum sensitivity, reminiscent of BRCA-mutant cases. These data are consistent with the notion that EMSY overexpression may render HGSOCs HR deficient.

Genome-wide bioinformatics analysis reveals CTCFL is upregulated in high-grade epithelial ovarian cancer

Epithelial ovarian cancer (EOC) is the most lethal gynecological malignancy that threatens the health of females. Previous studies have demonstrated that the survival outcomes of patients with different EOC grades varied. Therefore, the EOC grade is considered to serve as a distinctive prognostic factor. To date, the evaluation of ovarian cancer grade relies on pathological examination and a quantitative index for diagnosis is lacking. Furthermore, the dysregulation of genes has been demonstrated to exert pivotal functions in the carcinogenesis of EOCs. Therefore, the identification of effective biomarkers associated with EOC grade is of importance for the development of therapeutic regimens, and also contributes to the prediction of EOC prognosis. Microarrays have been increasingly applied for the identification of potential molecular biomarkers for numerous diseases including EOC. In the present study, four public microarray datasets (GSE26193, GSE63885, GSE30161 and GSE9891) were analyzed. A total of 6,103 upregulated probes corresponding to 5,766 genes, and 4,004 downregulated probes corresponding to 3,707 genes were identified in the GSE26193, GSE63885 and GSE30161 datasets. ALK and LTK ligand 2 was the most downregulated gene associated with the tumor grade, while CCCTC-binding factor like (CTCFL), EGF like domain multiple 6, radical S-adenosyl methionine domain containing 2 and SAM and HD domain containing deoxynucleoside triphosphate triphosphohydrolase 1 were the most upregulated genes associated with EOC grade. The GSE9891 dataset was added for further analysis. Only one probe (1552368_at) encoding for CTCFL was identified to be consistently upregulated in the four examined datasets. Immunohistochemical analysis was used to detect the expression of CTCFL between low- and high-grade EOC tissues and revealed that the EOC grade was closely associated with CTCFL level. This was corroborated via the reverse transcription-quantitative polymerase chain reaction. Taken together, the results of the present study suggested that CTCFL is upregulated in high-grade epithelial ovarian cancer.

Patients with BRCA mutated ovarian cancer may have fewer circulating MDSC and more peripheral CD8+ T cells compared with women with BRCA wild-type disease during the early disease course

Immunosuppressive myeloid-derived suppressor cells (MDSCs) and regulatory T cells (Tregs) are associated with immunologic tolerance and poor prognosis in ovarian cancer (OvCa). We hypothesized that women with germline BRCA1 and BRCA2 mutation-associated (gBRCAm) OvCa would have fewer circulating immunosuppressive immune cells compared to those with BRCA wild-type (BRCAwt) disease during their early disease course (<5 years post-diagnosis) where gBRCAm is a favorable prognostic factor. We collected and viably froze peripheral blood mononuclear cells (PBMCs) from patients with recurrent OvCa olaparib clinical trials (NCT01445418/NCT01237067). Immune subset analyses were performed using flow cytometry for Tregs, exhausted CD8⁺ T cells, monocytes and MDSCs. Functional marker expression, including cytotoxic T lymphocyte-associated protein 4 (CTLA-4), T cell immunoglobulin and mucin domain 3 (TIM-3) and programmed cell death protein 1 (PD-1) was evaluated. Data were analyzed using FlowJo. Pretreatment PBMCs were collected from 41 patients (16 gBRCAm/25 BRCAwt). The percentage of MDSCs among viable CD45⁺ PBMC was lower in gBRCAm OvCa compared with BRCAwt OvCa (median 0.565 vs. 0.93%, P=0.0086) but this difference was not seen in those women >5 years post-diagnosis. CD8⁺ T cells among viable CD45⁺ PBMCs and CTLA-4⁺/CD8⁺ T cells were higher in gBRCAm carriers than patients with BRCAwt, in particular for those <5 years post-diagnosis (median 20.4 vs. 9.78%, P=0.031 and median MFI 0.19 vs. 0.22, P=0.0074, respectively). TIM-3 expression on Tregs was associated with poor progression-free survival, independent of gBRCAm status (P<0.001). Our pilot data suggested that patients with gBRCAm OvCa may have fewer circulating MDSCs but higher CD8⁺ T cells in PBMCs during their early disease course. This may contribute to the observed survival benefit for these women in their first post-diagnosis decade.

Multi-level Proteomics Identifies CT45 as a Chemosensitivity Mediator and Immunotherapy Target in Ovarian Cancer

Most high-grade serous ovarian cancer (HGSOC) patients develop resistance to platinum-based chemotherapy and recur, but 15% remain disease free over a decade. To discover drivers of long-term survival, we quantitatively analyzed the proteomes of platinum-resistant and -sensitive HGSOC patients from minute amounts of formalin-fixed, paraffin-embedded tumors. This revealed cancer/testis antigen 45 (CT45) as an independent prognostic factor associated with a doubling of disease-free survival in advanced-stage HGSOC. Phospho- and interaction proteomics tied CT45 to DNA damage pathways through direct interaction with the PP4 phosphatase complex. In vitro, CT45 regulated PP4 activity, and its high expression led to increased DNA damage and platinum sensitivity. CT45-derived HLA class I peptides, identified by immunopeptidomics, activate patient-derived cytotoxic T cells and promote tumor cell killing. This study highlights the power of clinical cancer proteomics to identify targets for chemo- and immunotherapy and illuminate their biological roles.

Onset of Telomere Dysfunction and Fusions in Human Ovarian Carcinoma

Telomere dysfunction has been strongly implicated in the initiation of genomic instability and is suspected to be an early event in the carcinogenesis of human solid tumors. Recent findings have established the presence of telomere fusions in human breast and prostate malignancies; however, the onset of this genomic instability mechanism during progression of other solid cancers is not well understood. Herein, we explored telomere dynamics in patient-derived epithelial ovarian cancers (OC), a malignancy characterized by multiple distinct subtypes, extensive molecular heterogeneity, and widespread genomic instability. We discovered a high frequency of telomere fusions in ovarian tumor tissues; however, limited telomere fusions were detected in normal adjacent tissues or benign ovarian samples. In addition, we found relatively high levels of both telomerase activity and hTERT expression, along with anaphase bridges in tumor tissues, which were notably absent in adjacent normal ovarian tissues and benign lesions. These results suggest that telomere dysfunction may occur early in ovarian carcinogenesis and, importantly, that it may play a critical role in the initiation and progression of the disease. Recognizing telomere dysfunction as a pervasive feature of this heterogeneous malignancy may facilitate the future development of novel diagnostic tools and improved methods of disease monitoring and treatment.

Predictors of Long-Term Survival among High-Grade Serous Ovarian Cancer Patients

BACKGROUND

Relatively little is known about factors associated with long-term survival (LTS) following a diagnosis of ovarian cancer.

METHODS

We conducted a retrospective study of high-grade serous ovarian cancer (HGSOC) to explore predictors of LTS (defined as ≥7 years of survival) using electronic medical record data from a network of integrated health care systems. Multivariable logistic regression with forward selection was used to compare characteristics of women who survived ≥7 years after diagnosis (n = 148) to those who died within 7 years of diagnosis (n = 494).

RESULTS

Our final model included study site, age, stage at diagnosis, CA-125, comorbidity score, receipt of chemotherapy, BMI, and four separate comorbid conditions: weight loss, depression, hypothyroidism, and liver disease. Of these, only younger age, lower stage, and depression were statistically significantly associated with LTS.

CONCLUSIONS

We did not identify any new characteristics associated with HGSOC survival.

IMPACT

Prognosis of ovarian cancer generally remains poor. Large, pooled studies of ovarian cancer are needed to identify characteristics that may improve survival.

Invasive Epithelial Ovarian Cancer Survival by Histotype and Disease Stage

Background

The understanding of ovarian cancer pathogenesis has recently shifted to recognize distinct changes in how ovarian cancer histotypes are defined. Using the 2014 World Health Organization (WHO) diagnostic guidelines, we classified ovarian cancer histotypes in Surveillance, Epidemiology, and End Results (SEER) cancer registry data and examined survival patterns by histotype and disease stage.

Methods

We extracted data on 28 118 incident epithelial ovarian cancer cases diagnosed in 2004-2014 from SEER and defined histotype using the 2014 WHO guidelines (high-grade serous, low-grade serous, endometrioid, clear cell, mucinous, carcinosarcoma, and malignant Brenner tumors). By histotype and disease stage, we estimated Kaplan-Meier survival curves and calculated age-adjusted overall and cause-specific survival estimates. Cox proportional hazards regression models were used to estimate histotype-specific hazard ratios (HRs) and 95% confidence intervals (CIs) by disease stage while adjusting for age at diagnosis, region, race/ethnicity, and receipt of surgery.

Results

Within two years after diagnosis, localized/regional-stage carcinosarcoma and distant-stage mucinous, clear cell, and carcinosarcoma had a higher risk of mortality compared with high-grade serous, with the most pronounced association for localized/regional carcinosarcoma (>1-2-year time period: HR = 3.81, 95% CI = 2.74 to 5.30) and distant-stage mucinous (0-1-year time period: HR = 3.87, 95% CI = 3.45 to 4.34). In the time period more than four to 10 years after diagnosis, hazard ratios for all histotypes relative to high-grade serous, irrespective of disease stage, were less than 1.00. Cumulatively, both localized/regional and distant-stage low-grade serous and endometrioid carcinomas had the most favorable outcomes.

Conclusions

Our large study, which is representative of the United States population and incorporates the most current knowledge of ovarian cancer pathogenesis, highlights the need to recognize ovarian cancer as a set of distinct diseases and not a single entity. Only then will we be able to effectively target the unique features of each histotype to reduce ovarian cancer mortality.

The road to long-term survival: Surgical approach and longitudinal treatments of long-term survivors of advanced-stage serous ovarian cancer

OBJECTIVE

It is unclear if the types of surgical procedures performed on long-term survivors (LTS) of high-grade serous ovarian carcinoma (HGSOC) contribute to prolonged survival. In this case-control study we review the surgical procedures performed on LTS and describe their individual longitudinal disease courses.

METHODS

Women with FIGO stage III-IV high-grade serous cancer of the ovary, fallopian tube or peritoneum were selected from the University of Chicago ovarian cancer database. LTS were those surviving >7 years and controls were short-term survivors (STS) living 1-2 years. Patients with non-serous histology, low grade, and low malignant potential tumors were excluded.

RESULTS

We identified 450 women with stage III/IV HGSOC including 45 LTS and 78 STS. LTS showed a trend towards lower disease burden, yet underwent more aggressive surgical treatment. Interestingly, only 15 LTS (34%) were debulked to microscopic disease and 9 LTS (21%) underwent suboptimal debulking. Two LTS (5%) recurred within 12 months. LTS had heterogeneous clinical courses with 13 (29%) never experiencing a recurrence with 143 months median follow-up and 32 (71%) experiencing a recurrence with 115 months median follow-up. Of the women who recurred, 19 (59%) underwent at least one surgery for recurrence.

CONCLUSIONS

Aggressive surgical treatment intended to achieve microscopic disease, primary debulking surgery, preservation of sensitivity to chemotherapy, and recurrence amenable to secondary debulking are associated with long-term survival. However, clinicopathologic data are insufficient to predict long-term survival of HGSOC. Biologic characterization of these patient's tumors likely holds the key to understanding their unusually favorable courses.

Landscape of genomic alterations in high-grade serous ovarian cancer from exceptional long- and short-term survivors

BACKGROUND

Patients diagnosed with high-grade serous ovarian cancer (HGSOC) who received initial debulking surgery followed by platinum-based chemotherapy can experience highly variable clinical responses. A small percentage of women experience exceptional long-term survival (long term (LT), 10+ years), while others develop primary resistance to therapy and succumb to disease in less than 2 years (short term (ST)). To improve clinical management of HGSOC, there is a need to better characterize clinical and molecular profiles to identify factors that underpin these disparate survival responses.

METHODS

To identify clinical and tumor molecular biomarkers associated with exceptional clinical response or resistance, we conducted an integrated clinical, exome, and transcriptome analysis of 41 primary tumors from LT (n = 20) and ST (n = 21) HGSOC patients.

RESULTS

Younger age at diagnosis, no residual disease post debulking surgery and low CA125 levels following surgery and chemotherapy were clinical characteristics of LT. Tumors from LT survivors had increased somatic mutation burden (median 1.62 vs. 1.22 non-synonymous mutations/Mbp), frequent BRCA1/2 biallelic inactivation through mutation and loss of heterozygosity, and enrichment of activated CD4+, CD8+ T cells, and effector memory CD4+ T cells. Characteristics of ST survival included focal copy number gain of CCNE1, lack of BRCA mutation signature, low homologous recombination deficiency scores, and the presence of ESR1-CCDC170 gene fusion.

CONCLUSIONS

Our findings suggest that exceptional long- or short-term survival is determined by a concert of clinical, molecular, and microenvironment factors.

Landscape of genomic alterations in high-grade serous ovarian cancer from exceptional long- and short-term survivors

Background

Patients diagnosed with high-grade serous ovarian cancer (HGSOC) who received initial debulking surgery followed by platinum-based chemotherapy can experience highly variable clinical responses. A small percentage of women experience exceptional long-term survival (long term (LT), 10+ years), while others develop primary resistance to therapy and succumb to disease in less than 2 years (short term (ST)). To improve clinical management of HGSOC, there is a need to better characterize clinical and molecular profiles to identify factors that underpin these disparate survival responses.

Methods

To identify clinical and tumor molecular biomarkers associated with exceptional clinical response or resistance, we conducted an integrated clinical, exome, and transcriptome analysis of 41 primary tumors from LT (n = 20) and ST (n = 21) HGSOC patients.

Results

Younger age at diagnosis, no residual disease post debulking surgery and low CA125 levels following surgery and chemotherapy were clinical characteristics of LT. Tumors from LT survivors had increased somatic mutation burden (median 1.62 vs. 1.22 non-synonymous mutations/Mbp), frequent BRCA1/2 biallelic inactivation through mutation and loss of heterozygosity, and enrichment of activated CD4+, CD8+ T cells, and effector memory CD4+ T cells. Characteristics of ST survival included focal copy number gain of CCNE1, lack of BRCA mutation signature, low homologous recombination deficiency scores, and the presence of ESR1-CCDC170 gene fusion.

Conclusions

Our findings suggest that exceptional long- or short-term survival is determined by a concert of clinical, molecular, and microenvironment factors.

Electronic supplementary material

The online version of this article (10.1186/s13073-018-0590-x) contains supplementary material, which is available to authorized users.

Landscape of genomic alterations in high-grade serous ovarian cancer from exceptional long- and short-term survivors

BACKGROUND

Patients diagnosed with high-grade serous ovarian cancer (HGSOC) who received initial debulking surgery followed by platinum-based chemotherapy can experience highly variable clinical responses. A small percentage of women experience exceptional long-term survival (long term (LT), 10+ years), while others develop primary resistance to therapy and succumb to disease in less than 2 years (short term (ST)). To improve clinical management of HGSOC, there is a need to better characterize clinical and molecular profiles to identify factors that underpin these disparate survival responses.

METHODS

To identify clinical and tumor molecular biomarkers associated with exceptional clinical response or resistance, we conducted an integrated clinical, exome, and transcriptome analysis of 41 primary tumors from LT (n = 20) and ST (n = 21) HGSOC patients.

RESULTS

Younger age at diagnosis, no residual disease post debulking surgery and low CA125 levels following surgery and chemotherapy were clinical characteristics of LT. Tumors from LT survivors had increased somatic mutation burden (median 1.62 vs. 1.22 non-synonymous mutations/Mbp), frequent BRCA1/2 biallelic inactivation through mutation and loss of heterozygosity, and enrichment of activated CD4+, CD8+ T cells, and effector memory CD4+ T cells. Characteristics of ST survival included focal copy number gain of CCNE1, lack of BRCA mutation signature, low homologous recombination deficiency scores, and the presence of ESR1-CCDC170 gene fusion.

CONCLUSIONS

Our findings suggest that exceptional long- or short-term survival is determined by a concert of clinical, molecular, and microenvironment factors.

Long-term survival in patients with epithelial ovarian cancer following cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (HIPEC)

OBJECTIVE

Despite a high response rate to first-line therapy, prognosis of epithelial ovarian carcinoma (EOC) remains poor. The objective of the present study was to evaluate the frequency of long-term survivors and to identify the prognostic factors associated with long-term survival in a French cohort of 566 patients.

METHODS

Patients treated with cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) for EOC in 13 French centers between 1991 and 2010 were included. Long-term survivors were defined as patients who survived more than 5 years after HIPEC and CRS, irrespective of relapse.

RESULTS

Seventy-eight long-term survivors were analyzed. The median follow-up was 74 months. Median age at the time of first HIPEC was 55.4 years (range [22.6-77.6]. Seven patients had advanced EOC and 71 patients had recurrent EOC (37 patients had platinum-resistant EOC and 32 had platinum-sensitive disease). More than half of the long-term survivors had high-grade serous ovarian cancer (HGSOC). In univariate analysis, age ≥50 years (p = .004), peritoneal cancer index (PCI) ≤ 8 (p = .049) and CA-125 < 100 (p = .02) were associated with long-term survival. There was a trend towards an association between higher CC-score and long-term survival (p = .057).

CONCLUSION

Age ≥50 years, PCI ≤8 and CA125 < 100 were associated with long-term survival in univariate analysis. There was a trend towards the significance of CC-score. Platinum-status was not associated with long-term survival.

Morphology and tumour-infiltrating lymphocytes in high-stage, high-grade serous ovarian carcinoma correlated with long-term survival

AIMS

Advanced-stage ovarian high-grade serous carcinoma (HGSC) is a poor-prognosis cancer; however, a small and poorly characterised subset of patients shows long-term survival. We aimed to establish a cohort of HGSC long-term survivors for histopathological and molecular analysis.

METHODS AND RESULTS

Paraffin blocks from 151 patients with primary FIGO III/IV HGSC and progression-free survival (PFS) >5 years were collected within the Tumorbank Ovarian Cancer (TOC) Network; 77 HGSC with a PFS <3 years were used as a control group. A standardised analysis of histological type and morphological features was performed. Ki67 index, tumour-infiltrating lymphocytes (TILs) and major histocompatibility complex expression (MHC1/2) were determined by immunohistochemistry. A total of 117 of 151 tumours (77.5%) in the long-term survivor group fulfilled the World Health Organisation (WHO) criteria of HGSC after review, and of these, 83 patients (70.9%) fulfilled all clinical criteria for inclusion into our cohort. Tumours of long-term survivors had significantly higher CD3⁺ and CD8⁺ TILs and were more frequently positive for MHC2 than controls (P = 0.004, P = 0.025, P = 0.048). However, there were also long-term survivors (up to 20%) with low TILs or low MHC expression. TILs and MHC had no impact on survival in long-term survivors. Morphological and Ki67 analysis revealed no differences between long-term survivors and controls.

CONCLUSIONS

HGSC from long-term survivors have higher-level T cell infiltration and antigen-presentation capacity; however, this is not a prerequisite for an excellent prognosis. Histopathological criteria are not capable to identify these patients. Further extensive clinical and molecular characterisation of this enigmatic subgroup is ongoing to understand the reasons of long-term survival in HGSC.

Identification of Novel Somatic TP53 Mutations in Patients with High-Grade Serous Ovarian Cancer (HGSOC) Using Next-Generation Sequencing (NGS)

Somatic mutations in TP53 are a hallmark of high-grade serous ovarian cancer (HGSOC), although their prognostic and predictive value as markers is not well defined. Next-generation sequencing (NGS) can identify novel mutations with high sensitivity, that may be repurposed as potential druggable anti-cancer targets and aid in therapeutic decisions. Here, a commercial NGS cancer panel comprising 26 genes, including TP53, was used to identify new genetic markers of platinum resistance and patient prognosis in a retrospective set of patients diagnosed with epithelial ovarian cancer. Six novel TP53 somatic mutations in untreated tumors from six distinct patients diagnosed with HGSOC were identified: TP53 c.728_739delTGGGCGGCATGA (p.Met243_Met247del, in-frame insertion or deletion (INDEL); TP53 c.795_809delGGGACGGAACAGCTT (p.Gly266_Phe270del, in-frame INDEL); TP53 c.826_827GC>AT (p.Ala276Ile, missense); TP53 c.1022insT (p.Arg342Profs*5, frameshift INDEL); TP53 c.1180delT (p.Ter394Aspfs*28, frameshift INDEL); and TP53 c.573insT (p.Gln192Serfs*17, frameshift INDEL). Novel TP53 variants were validated by classical sequencing methods and their impact on protein expression in tumors explored by immunohistochemistry. Further insights into the potential functional effect of the mutations were obtained by different in silico approaches, bioinformatics tools, and structural modeling. This discovery of previously unreported TP53 somatic mutations provides an opportunity to translate NGS technology into personalized medicine and identify new potential targets for therapeutic applications.

Hyaluronic acid conjugated nanoparticle delivery of siRNA against TWIST reduces tumor burden and enhances sensitivity to cisplatin in ovarian cancer

TWIST protein is critical to development and is activated in many cancers. TWIST regulates epithelial-mesenchymal transition, and is linked to angiogenesis, metastasis, cancer stem cell phenotype, and drug resistance. The majority of epithelial ovarian cancer (EOC) patients with metastatic disease respond well to first-line chemotherapy but most relapse with disease that is both metastatic and drug resistant, leading to a five-year survival rate under 20%. We are investigating the role of TWIST in mediating these relapses. We demonstrate TWIST-siRNA (siTWIST) and a novel nanoparticle delivery platform to reverse chemoresistance in an EOC model. Hyaluronic-acid conjugated mesoporous silica nanoparticles (MSN-HAs) carried siTWIST into target cells and led to sustained TWIST knockdown in vitro. Mice treated with siTWIST-MSN-HA and cisplatin exhibited specific tumor targeting and reduction of tumor burden. This platform has potential application for overcoming clinical challenges of tumor cell targeting, metastasis and chemoresistance in ovarian and other TWIST overexpressing cancers.