Impact of BRCA Mutation Status on Tumor Dissemination Pattern, Surgical Outcome and Patient Survival in Primary and Recurrent High-Grade Serous Ovarian Cancer: A Multicenter Retrospective Study by the Ovarian Cancer Therapy-Innovative Models Prolong Survival (OCTIPS) Consortium.

BACKGROUND: This study seeks to evaluate the impact of breast cancer (BRCA) gene status on tumor dissemination pattern, surgical outcome and survival in a multicenter cohort of paired primary ovarian cancer (pOC) and recurrent ovarian cancer (rOC). PATIENTS AND METHODS: Medical records and follow-up data from 190 patients were gathered retrospectively. All patients had surgery at pOC and at least one further rOC surgery at four European high-volume centers. Patients were divided into one cohort with confirmed mutation for BRCA1 and/or BRCA2 (BRCAmut) and a second cohort with BRCA wild type or unknown (BRCAwt). Patterns of tumor presentation, surgical outcome and survival data were analyzed between the two groups. RESULTS: Patients with BRCAmut disease were on average 4 years younger and had significantly more tumor involvement upon diagnosis. Patients with BRCAmut disease showed higher debulking rates at all stages. Multivariate analysis showed that only patient age had significant predictive value for complete tumor resection in pOC. At rOC, however, only BRCAmut status significantly correlated with optimal debulking. Patients with BRCAmut disease showed significantly prolonged overall survival (OS) by 24.3 months. Progression-free survival (PFS) was prolonged in the BRCAmut group at all stages as well, reaching statistical significance during recurrence. CONCLUSIONS: Patients with BRCAmut disease showed a more aggressive course of disease with earlier onset and more extensive tumor dissemination at pOC. However, surgical outcome and OS were significantly better in patients with BRCAmut disease compared with patients with BRCAwt disease. We therefore propose to consider BRCAmut status in regard to patient selection for cytoreductive surgery, especially in rOC.

AID/APOBEC-network reconstruction identifies pathways associated with survival in ovarian cancer.

BACKGROUND: Building up of pathway-/disease-relevant signatures provides a persuasive tool for understanding the functional relevance of gene alterations and gene network associations in multifactorial human diseases. Ovarian cancer is a highly complex heterogeneous malignancy in respect of tumor anatomy, tumor microenvironment including pro-/antitumor immunity and inflammation; still, it is generally treated as single disease. Thus, further approaches to investigate novel aspects of ovarian cancer pathogenesis aiming to provide a personalized strategy to clinical decision making are of high priority. Herein we assessed the contribution of the AID/APOBEC family and their associated genes given the remarkable ability of AID and APOBECs to edit DNA/RNA, and as such, providing tools for genetic and epigenetic alterations potentially leading to reprogramming of tumor cells, stroma and immune cells. RESULTS: We structured the study by three consecutive analytical modules, which include the multigene-based expression profiling in a cohort of patients with primary serous ovarian cancer using a self-created AID/APOBEC-associated gene signature, building up of multivariable survival models with high predictive accuracy and nomination of top-ranked candidate/target genes according to their prognostic impact, and systems biology-based reconstruction of the AID/APOBEC-driven disease-relevant mechanisms using transcriptomics data from ovarian cancer samples. We demonstrated that inclusion of the AID/APOBEC signature-based variables significantly improves the clinicopathological variables-based survival prognostication allowing significant patient stratification. Furthermore, several of the profiling-derived variables such as ID3, PTPRC/CD45, AID, APOBEC3G, and ID2 exceed the prognostic impact of some clinicopathological variables. We next extended the signature-/modeling-based knowledge by extracting top genes co-regulated with target molecules in ovarian cancer tissues and dissected potential networks/pathways/regulators contributing to pathomechanisms. We thereby revealed that the AID/APOBEC-related network in ovarian cancer is particularly associated with remodeling/fibrotic pathways, altered immune response, and autoimmune disorders with inflammatory background. CONCLUSIONS: The herein study is, to our knowledge, the first one linking expression of entire AID/APOBECs and interacting genes with clinical outcome with respect to survival of cancer patients. Overall, data propose a novel AID/APOBEC-derived survival model for patient risk assessment and reconstitute mapping to molecular pathways. The established study algorithm can be applied further for any biologically relevant signature and any type of diseased tissue.

The 811 C/T polymorphism in the 3' untranslated region of the selenoprotein 15-kDa (Sep15) gene and breast cancer in Caucasian women.

The 15-kDa selenoprotein (Sep15) is a selenocysteine-containing oxidoreductase in the endoplasmic reticulum that participates in disulfide-bond formation and protein folding control. The 3'-untranslated region (3'-UTR) contains two exclusively linked, polymorphic sites at positions 811 (C/T) and 1125 (G/A), which result in two functional haplotypes: 811C/1125G or 811T/1125A. The 811T/1125A variant occurs significantly more often in African-Americans as compared to Caucasians and has been linked to increased breast cancer risk in black women. We studied the 811C/T (rs5845) Sep15 gene polymorphism in 182 Caucasian women-83 breast cancer cases and 99 healthy controls-by pyrosequencing and polymerase chain reaction. Associations between allelic variants and clinico-pathological variables (e.g., age, stage of disease, tumor type, grading, and receptor status) were investigated. The genotype distribution in breast cancer patients (CC 63.9 %, CT 33.7 %, TT 2.4 %) and controls (69.7 %, CT 28.3 %, TT 2 %) showed no significant difference (OR 0.77, 95 % CI 0.41-1.42, p = 0.4). The overall low prevalence of the T allele was in accordance with that reported for Caucasians in previous studies. There was no significant association between 811C/T Sep15 polymorphism and any of clinico-pathological parameters. In conclusion, we are the first to report on 811C/T SEP 15 polymorphism in white breast cancer patients. Genotype variation within the 3'-UTR of the SEP 15 gene showed no association with breast cancer risk or clinico-pathological parameters in Caucasian women.

Association of HER2 codon 655 polymorphism with ovarian cancer.

The role of the human epidermal growth factor receptor 2 (HER2) codon 655 (Ile655Val) polymorphism in ovarian cancer is not fully understood. Two studies indicated a possible association between the Val allele and elevated risk or reduced prognosis of ovarian cancer. We investigated the HER2 codon 655 (rs1136201) polymorphism in 242 Austrian women-142 ovarian cancer patients and 100 healthy controls-by polymerase chain reaction and pyrosequencing. Associations between Ile655Val polymorphism and clinicopathological variables (e.g., age, FIGO stage, grading, serous vs. non-serous histology) were evaluated. The genotype distributions in ovarian cancer patients and controls were: AA; 66.2 %, AG; 25.35 %, GG; 8.45 %, and AA; 63 %, AG; 34 %, GG; 3.7 %, respectively (OR 1.15, CI 95 % 0.67-1.96). We observed a non-significant trend toward elevated cancer risk in Val/Val genotype (OR 2.98, CI 95 % 0.82-10.87, p = 0.10). Of note, 11 out of 12 Val/Val homozygotes were postmenopausal. The link between the Val/Val homozygosity and age over 50 years at diagnosis (OR 0.15, CI 95 % 0.02-1.2) was barely significant (p = 0.056). Summarizing, our data indicated a non-significant trend toward increased ovarian cancer risk in the Val/Val homozygosity, especially in women aged above 50 years. Further large-cohort studies focusing on the role of the HER2 codon 655 Val allele are needed.

The role of HE4 for prediction of recurrence in epithelial ovarian cancer patients-results from the OVCAD study.

Patients with epithelial ovarian cancer (EOC) are at high risk of tumor recurrence. Human epididymis protein 4 (HE4) has been shown to be overexpressed in EOC. The primary aim of our study was to evaluate the role of HE4 in predicting recurrence in EOC patients. Furthermore, we assessed the role of HE4 in predicting recurrence after second-line chemotherapy. We retrospectively analyzed data of 92 out of 275 primary EOC patients of the multicenter project "Ovarian Cancer: Diagnosis of a silent killer" (OVCAD). The concentrations of HE4 and CA125 were determined preoperatively and 6 months after the end of platinum-based first-line chemotherapy (FU) using ELISA and Luminex technique, respectively. The role of HE4 and CA125 for prediction of recurrence was determined using receiver operating characteristics (ROC) curves. Out of 92 patients included, 70 (76 %) were responders and 22 (23 %) non-responders in terms of response to platinum-based first-line chemotherapy. Median HE4 concentrations at follow-up (FU) differed between responders and non-responders (60.5 vs. 237.25 pM, p = 0.0001), respectively. The combined use of HE4 and CA125 at FU with cut-off values of 49.5 pM and 25 U/ml for HE4 and CA125, respectively, for predicting recurrence within 12 months after first-line chemotherapy performed better than HE4 or CA125 alone (area under the curve (AUC) 0.928, 95 % confidence intervals (CI) 0.838-1, p < 0.001). HE4 at FU could predict recurrence within 6 months after second-line chemotherapy (AUC 0.719, 95 % CI 0.553-0.885, p = 0.024). The combination of both elevated biomarkers revealed significantly worse estimated median progression-free survival (PFS; hazard ratio (HR) 8.14, 95 % CI 3.75-17.68, p < 0.001) and slightly worse PFS in those in whom only one biomarker was elevated (HR 1.46, 95 % CI 0.72-2.96, p = 0.292) compared to those patients in whom no biomarker was elevated. For the estimated median overall survival (OS), our analysis revealed similar results. HE4 in combination with CA125 performed better than CA125 and HE4 alone in predicting recurrence within 12 months after first-line chemotherapy.

Association of -463G/A MPO gene polymorphism and risk of cervical intraepithelial neoplasia.

PURPOSE: The MPO system plays an important role in the control of infections and the deletion of malignant cells. Nevertheless, alternations in the MPO system can lead to DNA damage and carcinogenesis. Polymorphisms in the MPO Gene have been associated with an increased expression of MPO and a higher risk for development of cancer. This study evaluates the association between -463G/A MPO gene polymorphism and the risk for CIN. METHODS: The MPO gene polymorphism (-463G/A) was investigated in 616 women with cervical intraepithelial neoplasia and in 206 healthy women. Association between MPO gene polymorphism and risk of cervical intraepithelial neoplasia were analyzed by univariate and multivariable models. RESULTS: No significant difference in genotype distribution of the MPO gene polymorphism was observed in women with CIN and controls (p = 0.4; OR 1.2, 95 % CI 0.8-1.6). A subgroup analysis only including women with CIN did not show an association between -463G/A MPO gene polymorphism and risk for high-grade CIN (CIN 2/3) (p = 0.09; OR 1.5, 95 % CI 0.9-2.3). CONCLUSIONS: The investigated MPO gene polymorphism is not associated with risk for the development of cervical intraepithelial neoplasia.

Ambivalent role of pFAK-Y397 in serous ovarian cancer--a study of the OVCAD consortium.

BACKGROUND: Focal adhesion kinase (FAK) autophosphorylation seems to be a potential therapeutic target but little is known about the role and prognostic value of FAK and pFAK in epithelial ovarian cancer (EOC). Recently, we validated a gene signature classifying EOC patients into two subclasses and revealing genes of the focal adhesion pathway as significantly deregulated. METHODS: FAK expression and pFAK-Y397 abundance were elucidated by immunohistochemistry and microarray analysis in 179 serous EOC patients. In particular the prognostic value of phosphorylated FAK (pFAK-Y397) and FAK in advanced stage EOC was investigated. RESULTS: Multiple Cox-regression analysis showed that high pFAK abundance was associated with improved overall survival (HR 0.54; p = 0.034). FAK was positive in a total of 92.2% (n = 165) and high pFAK abundance was found in 36.9% (n = 66). High pFAK abundance (36.9% ; n = 66) was associated with either nodal positivity and/or distant metastasis (p = 0.030). Whole genome gene expression data revealed a connection of the FAK-pFAK-Y397 axis and the mTOR-S6K1 pathway, shown to play a major role in carcinogenesis. CONCLUSION: The role of pFAK-Y397 remains controversial: although high pFAK-Y397 abundance is associated with distant and lymph node metastases, it is independently associated with improved overall survival.

Association of myeloperoxidase with ovarian cancer.

Myeloperoxidase (MPO) is an oxidant generating enzyme normally restricted to myeloid cells, however aberrant MPO expression has been found to occur in non-myeloid cells in some disease states. The functional -463GA promoter polymorphism alters MPO expression levels. The -463G is within an SP1 binding site and is associated with higher gene expression. The G allele is most frequent with ~62% of European populations being GG homozygotes. The GA polymorphism has been associated with risk or survival in a variety of cancers including lung and breast cancer. In this study we determined the frequency of the -463G/A polymorphism in 230 ovarian cancer patients, 75 patients with borderline ovarian tumors, and 299 healthy controls. The GG genotype was found to be overrepresented in patients with early stage ovarian cancer (83.3% GG, p = 0.008) as compared to healthy controls (62% GG), suggesting that MPO oxidants may increase risk. Immunohistochemical analysis revealed MPO expression in a subset of columnar ovarian epithelial carcinoma cells in early stage carcinomas.

Somatic copy number alterations predict response to platinum therapy in epithelial ovarian cancer.

OBJECTIVE: Platinum resistance remains an obstacle in the treatment of epithelial ovarian cancer (EOC). The goal of this study was to profile EOCs for somatic copy number alterations (SCNAs) as predictive markers of platinum response. METHODS: SCNAs were assessed in a discovery (n=86) and validation cohort (n=115) of high risk stage I or stage II-IV EOCs using high-resolution SNP arrays. ASCAT and GISTIC identified all significantly overrepresented amplified or deleted chromosomal regions. Cox regression and univariate analysis assessed which SCNAs correlated with overall survival (OS), progression-free survival (PFS), platinum-free interval (PFI) and platinum response. Relevant SCNAs were also assessed in a pooled analysis involving both cohorts and published SCNA data from The Cancer Genome Atlas (TCGA; n=227). RESULTS: We identified 53 regions to be significantly overrepresented in EOC. Of these, 6 were associated with OS, PFS or PFI in the discovery cohort at P<0.05. In the validation cohort, amplifications of chromosomal region 14q32.33, which contains AKT1 as a potential driver gene, also correlated with OS (OR=1.670; P=0.018). In a pooled analysis of 428 tumors, involving the discovery, validation and TCGA cohorts, 14q32.33 amplifications significantly reduced OS, PFS and PFI (HR=2.69, P=1.7×10(-4); HR=1.82, P=1.9×10(-2) and HR=1.80, P=2.2×10(-2) respectively). Moreover, AKT1 mRNA expression correlated with the number of chromosomal copies of the 14q32.33 region (P=2.8×10(-11);R(2)=0.26). CONCLUSIONS: We established that amplifications in 14q32.33 were associated with reduced OS, PFS, PFI and platinum resistance in three independent cohorts, suggesting that AKT1 amplifications act as a potentially predictive marker for EOC treated with platinum-based chemotherapy.

Prognostic impact of tumor infiltrating CD8+ T cells in association with cell proliferation in ovarian cancer patients--a study of the OVCAD consortium.

BACKGROUND: Epithelial ovarian cancer is one of the most lethal gynecologic malignancies. Clinicopathological factors do not permit precise prognosis and cannot provide guidance to specific treatments. In this study we assessed tumor infiltrating CD8+ T cells in association with Ki67 proliferation index and evaluated their prognostic impact in EOC samples. METHODS: CD8+ cells and Ki67 proliferation index were immunohistochemically determined on tissue microarrays including 203 primary epithelial ovarian tumors. Additionally, CD8 gene expression was assessed with RT-qPCR. Correlations were analyzed using Pearson's correlation coefficients, ANOVA or T-test, or Fischer's exact tests. Prognostic impact was evaluated using the Kaplan-Meier method and Cox regression model. RESULTS: The density of CD8+ infiltrating lymphocytes did not correlate with tumor cell proliferation. Epithelial ovarian cancer patients with no Ki67+ cells in the tumor had a more than three times higher risk to die compared to the population with Ki67+ cells in the tumor (Hazard ratio (HR) = 3.34, 95%CI 1.59-7.04). High CD8+ cell infiltration was associated with improved overall survival (HR = 0.82, 95%CI 0.73-0.92). CONCLUSIONS: The density of tumor infiltrating lymphocytes is independent of tumor cell proliferation. Ovarian cancer patients with Ki67- tumors showed a significantly reduced overall survival, presumably due to no or poor response to platinum-based chemotherapy. Moreover, the association of high densities of tumor infiltrating cytotoxic T lymphocytes with a better overall survival was confirmed.

Molecular characterization of circulating tumor cells in patients with ovarian cancer improves their prognostic significance -- a study of the OVCAD consortium.

OBJECTIVE: The study aims at identifying novel markers for circulating tumor cells (CTCs) in patients with epithelial ovarian cancer (EOC), and at evaluating their impact on outcome. METHODS: Microarray analysis comparing matched EOC tissues and peripheral blood leucocytes (N=35) was performed to identify novel CTC markers. Gene expression of these novel markers and of EpCAM was analyzed using RT-qPCR in blood samples taken from healthy females (N=39) and from EOC patients (N=216) before primary treatment and six months after adjuvant chemotherapy. All samples were enriched by density gradient centrifugation. CTC positivity was defined by over-expression of at least one gene as compared to the healthy control group. RESULTS: CTC were detected in 24.5% of the baseline and 20.4% of the follow-up samples, of which two thirds were identified by overexpression of the cyclophilin C gene (PPIC), and just a few by EpCAM overexpression. The presence of CTCs at baseline correlated with the presence of ascites, sub-optimal debulking, and elevated CA-125 and HE-4 levels, whereas CTC during follow-up occurred more often in older and platinum resistant patients. PPIC positive CTCs during follow-up were significantly more often detected in the platinum resistant than in the platinum sensitive patient group, and indicated poor outcome independent from classical prognostic parameters. CONCLUSIONS: Molecular characterization of CTC is superior to a mere CTC enumeration or even be the rationale for CTC diagnostics at all. Ultimately CTC diagnostics may lead to more personalized treatment of EOC, especially in the recurrent situation.

Plasma concentrations of the vitamin E-binding protein afamin are associated with overall and progression-free survival and platinum sensitivity in serous ovarian cancer--a study by the OVCAD consortium.

OBJECTIVE: Comparative proteomics identified the plasma protein afamin as potential biomarker for ovarian cancer (OC). Significantly decreased afamin plasma concentrations in pre-therapeutic OC patients reconstituted to control values after successful tumor surgery. This study evaluates the association of afamin with survival and response to therapy in serous OC patients within the OVCAD consortium project. METHODS: We measured afamin in 215 pre-therapeutic plasma samples, 246 tumor lysates and 109 plasma samples taken 6months after finishing platinum-based chemotherapy. Differences in afamin plasma concentrations among FIGO stages were tested by Kruskal-Wallis test; association of afamin concentrations with overall and progression-free survival was evaluated using Kaplan-Meier survival plots and multivariate adjusted COX regression analysis. RESULTS: Pre-therapeutic afamin correlated significantly with FIGO stages (p=0.012) and was lower in the presence of metastases (p=0.013) and poorly differentiated OC in patients responding to therapy (p=0.016). Afamin ≥48.0mg/L was also associated with a lower hazard ratio for recurrent disease as compared to afamin <48.0mg/L (p=0.007). Post-therapeutic afamin ≥48mg/L was positively correlated with overall (p<0.001) and progression-free (p=0.012) survival and was lower in non-responders than in responders (p=0.048). Thus, afamin returned post-therapeutically to values of healthy controls in responders (p<0.001) but not in non-responders (p=0.114). Afamin in tumor lysates was lower in poorly differentiated OC than in G 1+2 tumors (p=0.041). Higher afamin concentrations in tumor lysates were associated with increased overall survival (p=0.003). CONCLUSION: These data indicate that afamin is associated with therapy response and survival rate in advanced OC patients.

Outcome and clinical management of 275 patients with advanced ovarian cancer International Federation of Obstetrics and Gynecology II to IV inside the European Ovarian Cancer Translational Research Consortium-OVCAD.

INTRODUCTION: The Sixth Framework Program European Union project OVCAD, "Ovarian Cancer-Diagnosis of a Silent Killer," aimed to investigate new predictors for early detection of minimal residual disease in epithelial ovarian cancer (EOC). Here we present the main pathologic, surgical, and chemotherapy characteristics of the OVCAD patient cohort. METHODS: Between February 2005 and December 2008, 5 European gynecologic cancer centers (WP2 group) enrolled prospective 275 consecutive patients with EOC into this translational study. Inclusion criteria were as follows: advanced International Federation of Obstetrics and Gynecology II to IV stage, cytoreductive surgery, platinum-based chemotherapy, and collected tumor samples. WP2 coordinated the implementation, screening, and recruiting of the patients and tumor samples into a Web-based data bank according established standard operating procedures. RESULTS: Median age at the time of diagnosis was 58 years. Most patients presented advanced high-grade EOC: International Federation of Obstetrics and Gynecology III/IV (94.5%), grade 2/3 (96%), serous histology (86.2%), ascites (76%), peritoneal carcinomatosis (67.6%), and lymph node involvement (52%). The most common surgical procedures were omentectomy (92.4%), bilateral salpingo-oophorectomy (90.9%), hysterectomy (77.3%), pelvic (69.5%) and paraaortic (66.9%) lymphadenectomy, and large (37.7%) or small bowel resection (13.4%). Patients were treated commonly with platinum-based therapy (98.2%). The macroscopic cytoreduction rate was 68.4%. After a median follow-up of 37 months, 70 patients (25.5%) developed a platinum-resistant recurrence. Biological materials such as tumor and paraffin tissue, ascites, and blood samples were collected consecutively. CONCLUSIONS: The implementation of the OVCAD cohort demonstrated the feasibility and advantages of an open, prospective, and multicenter recruitment inside a translational research study. Essential was the predefinition of all inclusion criteria, standard operating procedures, and Web-based software, which enabled the prospective patient recruitment and tissue sampling, minimizing institutional bias and variability in the quality of the biological samples. The translational concept of the OVCAD study does not conflict with the state-of-the-art surgical and chemotherapy management and guaranteed an improved outcome of patients with EOC.

Fibroblast growth factor receptor 4 gene (FGFR4) 388Arg allele predicts prolonged survival and platinum sensitivity in advanced ovarian cancer.

FGFR4 has been shown to play an important role in the etiology and progression of solid tumors. A single nucleotide polymorphism (SNP) within the FGFR4 gene has previously been linked to prognosis and response to chemotherapy in breast cancer and other malignancies. This study evaluates the relevance of this SNP in advanced ovarian cancer. FGFR4-genotype was analyzed in 236 patients recruited as part of the OVCAD project. Genotyping was performed on germ-line DNA using a TaqMan based genotyping assay. Results were correlated with clinicopathological variables and survival. The FGFR4 388Arg genotype was significantly associated with prolonged progression-free and overall survival (univariate: HR 0.68, p = 0.017; HR 0.49, p = 0.005; multivariate: HR 0.69, p = 0.025; HR 0.49, p = 0.006) though the positive prognostic value was restricted to patients without postoperative residual tumor. Indeed, there was a significant interaction between FGFR4 genotype and residual tumor for overall survival. Furthermore, the FGFR4 388Arg genotype significantly correlated with platinum sensitivity in the same subgroup (multivariate OR 3.81 p = 0.004). FGFR4 Arg388Gly genotype is an independent and strong context specific prognostic factor in patients with advanced ovarian cancer and could be used to predict platinum-sensitivity.

Prognostic value of residual tumor size in patients with epithelial ovarian cancer FIGO stages IIA-IV: analysis of the OVCAD data.

OBJECTIVE: The objective of the study was to evaluate the prognostic impact of residual tumor size after cytoreductive surgery in patients with epithelial ovarian cancer. METHODS: In this prospective, multicenter study, 226 patients with epithelial ovarian cancer (International Federation of Gynecology and Obstetrics stages IIA-IV) were included. Patients were treated with cytoreductive surgery and adjuvant platinum-based chemotherapy. Univariate and multivariable survival analyses were performed to investigate the impact of residual tumor size on progression-free and overall survival. RESULTS: In 69.4% of patients, surgery resulted in complete tumor resection; minimal residual disease (≤1 cm) was achieved in 87.2% of patients. Advanced tumor stage was associated with a lower rate of complete tumor resection (P < 0.001). After cytoreductive surgery, 3-year overall survival rates were 72.4%, 65.8%, and 45.2% for patients without, with minimal, and with gross residual disease (>1 cm), respectively (P < 0.001). Multivariable survival analysis revealed residual tumor size (P = 0.04) and older patient age (P = 0.02) as independent prognosticators for impaired overall survival. Complete cytoreduction was predictive for a higher rate of treatment response (P = 0.001) and was associated with prolonged progression-free and overall survival (P < 0.001 and P = 0.001). CONCLUSIONS: The size of residual disease after cytoreduction is one of the most crucial prognostic factors for patients with ovarian cancer. Patients after complete cytoreduction have a superior outcome compared with patients with residual disease. Leaving no residual tumor has to be the aim of primary surgery for ovarian cancer; therefore, patients should receive treatment at centers able to undertake complex cytoreductive procedures.

Gene Expression of Kallikreins in Breast Cancer Cell Lines.

BACKGROUND/AIM: This study analyzed the gene expression of the "classic" KLK1 and "new" kallikreins KLK4-KLK15, in relation to the molecular characteristics and in vitro invasiveness of 21 breast cancer (BC) and three normal breast-derived cell lines (CLs). MATERIALS AND METHODS: Gene expression of KLKs was determined by using real-time polymerase chain reaction (PCR). The invasiveness of the CLs was examined using a fibroblast-collagen-based in vitro cell culture assay. RESULTS: KLK5 and KLK7-KLK11 were down-regulated in several BCCLs. In contrast, KLK4, KLK8, KLK12 and KLK15 demonstrated strikingly high expression in two BCCLs, UACC 812 and MDA-MB 330. The KLK expression differed frequently according to the presence of androgen receptor (KLK1 and KLK5-KLK9), and occasionally according to estrogen receptor (KLK9) and EGFR (KLK7). Two KLK clusters were detected (first: KLK1, 4, 12, 15; second: all other KLKs), with two subclasses within the second cluster (KLK5-9 and KLK10, 11, 13, and 14). The CLs that expressed at least six KLKs belonged predominantly to basal or HER2 intrinsic subtypes. No KLK predicted the in vitro invasiveness of CLs. CONCLUSION: Gene expression of KLKs was altered in BCCLs. This change was mostly down-regulation and often related to the presence of androgen receptor. The observed clusters point to a possible functional interplay of selected KLKs in BCCLs.

Metabolism of Estrogens: Turnover Differs Between Platinum-Sensitive and -Resistant High-Grade Serous Ovarian Cancer Cells.

High-grade serous ovarian cancer (HGSOC) is currently treated with cytoreductive surgery and platinum-based chemotherapy. The majority of patients show a primary response; however, many rapidly develop drug resistance. Antiestrogens have been studied as low toxic treatment options for HGSOC, with higher response rates in platinum-sensitive cases. Mechanisms for this difference in response remain unknown. Therefore, the present study investigated the impact of platinum resistance on steroid metabolism in six established HGSOC cell lines sensitive and resistant against carboplatin using a high-resolution mass spectrometry assay to simultaneously quantify the ten main steroids of the estrogenic metabolic pathway. An up to 60-fold higher formation of steroid hormones and their sulfated or glucuronidated metabolites was observed in carboplatin-sensitive cells, which was reversible by treatment with interleukin-6 (IL-6). Conversely, treatment of carboplatin-resistant cells expressing high levels of endogenous IL-6 with the monoclonal anti-IL-6R antibody tocilizumab changed their status to "platinum-sensitive", exhibiting a decreased IC50 value for carboplatin, decreased growth, and significantly higher estrogen metabolism. Analysis of these metabolic differences could help to detect platinum resistance in HGSOC patients earlier, thereby allowing more efficient interventions.

Changes in the Tumor Immune Microenvironment during Disease Progression in Patients with Ovarian Cancer.

Anti-PD1/PDL1 therapy has proven efficacious against many cancers but only reached modest objective response rates against recurrent ovarian cancer. A deeper understanding of the tumor microenvironment (TME) may reveal other immunosuppressive mechanisms that warrant investigation as immunotherapeutic targets for this challenging disease. Matched primary and recurrent tumors from patients with high-grade serous ovarian carcinoma (HGSC) were analyzed by multicolor immunohistochemistry/immunofluorescence for the presence of T cells, B cells, macrophages, and for the expression of immunosuppressive and HLA molecules. Cancer- and immune-related gene expression was assessed by NanoString analysis. Recurrent tumors showed increased infiltration by immune cells, displayed higher expression of PDL1, IDO, and HLA molecules, and contained more stromal tissue. NanoString analysis demonstrated increased expression of gene signatures related to chemokines and T cell functions in recurrent tumors. The ovarian tumors showed high gene expression of LAG3 and HAVCR2 (TIM3) and enhanced levels of TIGIT and CTLA4 in recurrent tumors compared to primary tumors. The majority of HGSC developed into a more inflamed phenotype during progression from primary to recurrent disease, including indications of adaptive immune resistance. This suggests that recurrent tumors may be particularly sensitive to inhibition of adaptive immune resistance mechanisms.

USP1 links platinum resistance to cancer cell dissemination by regulating Snail stability.

Resistance to platinum-based chemotherapy is a common event in patients with cancer, generally associated with tumor dissemination and metastasis. Whether platinum treatment per se activates molecular pathways linked to tumor spreading is not known. Here, we report that the ubiquitin-specific protease 1 (USP1) mediates ovarian cancer cell resistance to platinum, by regulating the stability of Snail, which, in turn, promotes tumor dissemination. At the molecular level, we observed that upon platinum treatment, USP1 is phosphorylated by ATM and ATR and binds to Snail. Then, USP1 de-ubiquitinates and stabilizes Snail expression, conferring resistance to platinum, increased stem cell-like features, and metastatic ability. Consistently, knockout or pharmacological inhibition of USP1 increased platinum sensitivity and decreased metastatic dissemination in a Snail-dependent manner. Our findings identify Snail as a USP1 target and open the way to a novel strategy to overcome platinum resistance and more successfully treat patients with ovarian cancer.