Outcome In Epithelial Ovarian Cancer Research Articles

The Impact of Perioperative Packed Red Blood Cell Transfusion on Survival in Epithelial Ovarian Cancer

Perioperative packed red blood cell transfusion (PRBCT) has been implicated as a negative prognostic marker in surgical oncology. There is a paucity of evidence on the impact of PRBCT on outcomes in epithelial ovarian cancer (EOC). We assessed whether PRBCT is an independent risk factor of recurrence and death from EOC. Perioperative patient characteristics and process-of-care variables (defined by the National Surgical Quality Improvement Program) were retrospectively abstracted from 587 women who underwent primary EOC staging between January 2, 2003, and December 29, 2008. Associations with receipt of PRBCT were evaluated using univariate logistic regression models. The associations between receipt of PRBCT and disease-free survival and overall survival were evaluated using multivariable Cox proportional hazards models and using propensity score matching and stratification, respectively. The rate of PRBCT was 77.0%. The mean ± SD units transfused was 4.1 ± 3.1 U. In the univariate analysis, receipt of PRBCT was significantly associated with older age, advanced stage (≥ IIIA), undergoing splenectomy, higher surgical complexity, serous histologic diagnosis, greater estimated blood loss, longer operating time, the presence of residual disease, and lower preoperative albumin and hemoglobin. Perioperative packed red blood cell transfusion was not associated with an increased risk for recurrence or death, in an analysis adjusting for other risk factors in a multivariable model or in an analysis using propensity score matching or stratification to control for differences between the patients with and without PRBCT. Perioperative packed red blood cell transfusion does not seem to be directly associated with recurrence and death in EOC. However, lower preoperative hemoglobin was associated with a higher risk for recurrence. The need for PRBCT seems to be a stronger prognostic indicator than the receipt of PRBCT.

BRCA mutations and outcome in epithelial ovarian cancer (EOC): experience in ethnically diverse groups

BackgroundEpithelial ovarian cancer (EOC) patients with BRCA mutations have better prognosis than nonhereditary cases matched for histology and stage and age at diagnosis, especially Ashkenazi Jews (AJ). Materials and methodsWe retrospectively reviewed data on 700 highly ethnically heterogeneous patients diagnosed with stage Ic–IV EOC and evaluated for BRCA status between 1995 and 2009 in American, Israeli, and Italian medical centers. ResultsThe ethnicities of the 190 patients (median age 55.5 years, range 31–83 years) were AJ, Jewish non-Ashkenazi, Caucasian, African-American, Hispanic, or unknown. Ninety were BRCA1/2 carriers (71 BRCA1 and 19BRCA2). The most common mutations in AJ and non-AJ origins were 185delAG and 6174delT. Non-Jewish Caucasians exhibited the widest variation (>20 mutation subtypes). BRCA carriers had significantly prolonged median overall survival (93.6 months) compared with noncarriers (66.6 months; 95% confidence interval 44.5–91.7, P = 0.0081). There was no difference in progression-free survival. ConclusionsOur data demonstrate a wide variety of BRCA mutations in a highly ethnically diverse EOC population, and confirm that EOC BRCA mutation carriers have better prognosis with longer median survival than patients with nonhereditary disease. The contribution of unclassified BRCA variants to cancer etiology remains undetermined.

Abstract 5: Factors leading to racial disparities in treatment and outcomes of epithelial ovarian cancer

Abstract 5: Factors leading to racial disparities in treatment and outcomes of epithelial ovarian cancer

ABCB1 (MDR1) polymorphisms and ovarian cancer progression and survival: A comprehensive analysis from the Ovarian Cancer Association Consortium and The Cancer Genome Atlas

ObjectiveABCB1 encodes the multi-drug efflux pump P-glycoprotein (P-gp) and has been implicated in multi-drug resistance. We comprehensively evaluated this gene and flanking regions for an association with clinical outcome in epithelial ovarian cancer (EOC). MethodsThe best candidates from fine-mapping analysis of 21 ABCB1 SNPs tagging C1236T (rs1128503), G2677T/A (rs2032582), and C3435T (rs1045642) were analysed in 4616 European invasive EOC patients from thirteen Ovarian Cancer Association Consortium (OCAC) studies and The Cancer Genome Atlas (TCGA). Additionally we analysed 1,562 imputed SNPs around ABCB1 in patients receiving cytoreductive surgery and either ‘standard’ first-line paclitaxel–carboplatin chemotherapy (n=1158) or any first-line chemotherapy regimen (n=2867). We also evaluated ABCB1 expression in primary tumours from 143 EOC patients. ResultFine-mapping revealed that rs1128503, rs2032582, and rs1045642 were the best candidates in optimally debulked patients. However, we observed no significant association between any SNP and either progression-free survival or overall survival in analysis of data from 14 studies. There was a marginal association between rs1128503 and overall survival in patients with nil residual disease (HR 0.88, 95% CI 0.77–1.01; p=0.07). In contrast, ABCB1 expression in the primary tumour may confer worse prognosis in patients with sub-optimally debulked tumours. ConclusionOur study represents the largest analysis of ABCB1 SNPs and EOC progression and survival to date, but has not identified additional signals, or validated reported associations with progression-free survival for rs1128503, rs2032582, and rs1045642. However, we cannot rule out the possibility of a subtle effect of rs1128503, or other SNPs linked to it, on overall survival.

Overexpression of c-Abl predicts unfavorable outcome in epithelial ovarian cancer

ObjectivesAbelson tyrosine kinase (c-Abl) has been shown to promote solid tumor invasion and metastasis. However, little is known regarding whether c-Abl contributes to the development or progression of epithelial ovarian cancer (EOC). The aims of this study are to determine the expression of c-Abl and investigate a possible relationship between c-Abl and prognosis in EOC. Methodsc-Abl protein level was evaluated in 137 EOC specimens by immunohistochemical staining and 32 EOC specimens by Western blot analysis. Expression of c-Abl in ovarian cancer cell lines was measured by Western blot analysis and immunofluorescence. Survival analysis was performed to assess the correlation between c-Abl expression and survival. ResultsImmunohistochemical staining and Western blot analysis revealed that c-Abl was overexpressed in EOC compared with samples from a non-invasive ovarian tumor and normal ovaries (P<0.05). Furthermore, expression of c-Abl was significantly associated with advanced FIGO stage, poor grade, serum Ca-125 and residual tumor size (P<0.05). By Western blot analysis, c-Abl expression was examined in four ovarian cancer cell lines. Meanwhile, immunofluorescence was performed to show c-Abl expression in SKOV3 and 3AO cell lines. Survival analysis demonstrated that patients with low c-Abl staining had a significantly better survival compared to patients with high c-Abl staining (P<0.05). In multivariate analysis, c-Abl overexpression, poor grade, advanced stage and suboptimal surgical debulking were independent prognostic factors of poor survival. ConclusionsOur present study finds that c-Abl overexpression is associated with an unfavorable outcome. c-Abl may be a crucial predictor for EOC metastasis.

Factors leading to racial disparities in treatment and outcomes of epithelial ovarian cancer

Factors leading to racial disparities in treatment and outcomes of epithelial ovarian cancer

Surgical outcome score (SOS), a new algorithm based on HE4 and CA125, to predict surgical outcome in primary epithelial ovarian cancer (EOC) patients (pts).

5549 Background: There are no clinical or biomolecular algorithms to predict surgical outcome in EOC pts. Recently, we showed that the combination of HE4 and CA125 predict surgical outcome in advanced primary EOC (ASCO 2012). We validated the cut-off values in an independent cohort and developed a new algorithm to predict surgical outcome-SOS. Methods: Pts with primary EOC (n = 193) were selected for a retrospective study between 2003 and 2011. Preoperative serum HE4 and CA125 levels were measured. The predictive values of HE4 and CA125 were analyzed using the receiver operator characteristic (ROC) with the corresponding area under the curve (AUC). Separate logistic regression algorithms for pre- and postmenopausal women were utilized to categorize pts into low and high-risk for residual disease, using CA125 and HE4 within SOS algorithm. Furthermore we performed a multivariate analysis for prediction of progression free- (PFS) and overall survival (OS). Results: Maximal cytoreduction was achieved in 67.4% pts. Serum HE4 expression correlated with residual disease (p&lt;0.001, RR: 2.74, 95%CI 1.65-4.54), reaching a 76.2% sensitivity (Se), 56.9% specificity (Sp) and 83.1% negative predictive value (NPV), with 235 pM cut-off value. CA125 correlated with residual disease in premenopausal pts (p=0.031, RR: 3.13, 95%CI 1.28-7.65). For a CA125 cut-off of 500 IU/l, the Se, Sp and NPV were 39.7%, 69.8%, and 70.3%, respectively. ROMA predicted surgical outcome (AUC = 0.70, p &lt;0.001, 95% CI = 0.624-0.776, RR = 2.54), reaching a 76.2% Se, 53.5% Sp for 81% cut-off value. SOS algorithm performed better than HE4 or CA125 alone, and ROMA (AUC= 0.741, p &lt; 0.001, 95% CI 0.670-0.812, RR = 4.98). The Se, Sp and NPV was 90.5%, 46.5% and 90.9%, respectively, for a SOS cut off value of 21.5%. FIGO stage and residual disease were the only prognostic factors for both PFS and OS. SOS was an independent prognostic for PFS (p = 0.009, HR = 1.014, 95% CI = 1.004-1.025), but not for OS. Conclusions: This independent validation study confirm the predictive value of CA124 and HE4 on surgical outcome. The combination of HE4 and CA125 within the SOS score improve the prediction of surgical outcome, and therefore of PFS.

DNA Repair Gene Associated with Clinical Outcome of Epithelial Ovarian Cancer Treated with Platinum-based Chemotherapy

The nucleotide excision repair (NER) and base excision repair (BER) pathways, two DNA repair pathways, are related to platinum resistance in cancer treatment. In this paper, we studied the association between single nucleotide polymorphisms (SNPs) of involved genes and response to platinum-based chemotherapy in epithelial ovarian cancer. Eight SNPs in XRCC1 (BER), XPC and XPD (NER) were assessed in 213 patients with epithelial ovarian cancer using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and primer-introduced restriction analysis-polymerase chain reaction (PIRA-PCR) techniques. The median progression-free survival (PFS) of patients carrying the Lys/Lys and Lys/Gln+Gln/Gln genotype of the XPC Lys/Gln polymorphism were 25 and 12 months, respectively (P=0.039); and the mean overall survival (OS) of patients was 31.1 and 27.8 months, respectively (P=0.048). Cox's multivariate analysis suggested that patients with epithelial ovarian cancer with the Gln allele had an increased risk of death (HR=1.75; 95% CI=1.06-2.91) compared to those with the Lys/Lys genotype. There are no associations between the XPC PAT+/-, XRCC1 Arg194Trp, Arg280His, Arg399Gln, and XPD Asp312Asn, Lys751Gln polymorphisms and the survival of patients with epithelial ovarian cancer when treated with platinum-based chemotherapy. Our results indicated that the XPC Lys939Gln polymorphism may correlate with clinical outcome of patients with epithelial ovarian cancer when treated with platinum-based chemotherapy in Northern China.

Trends in incidence and survival outcome of epithelial ovarian cancer: 30-year national population-based registry in Taiwan

ObjectiveTo investigate the changes of incidence and prognosis of epithelial ovarian cancer in thirty years in Taiwan.MethodsThe databases of women with epithelial ovarian cancer during the period from 1979 to 2008 were retrieved from the National Cancer Registration System of Taiwan. The incidence and prognosis of these patients were analyzed.ResultsTotally 9,491 patients were included in the study. The age-adjusted incidences of epithelial ovarian cancer were 1.01, 1.37, 2.37, 3.24, 4.18, and 6.33 per 100,000 person-years, respectively, in every 5-year period from 1979 to 2008. The age-specific incidence rates increased especially in serous, endometrioid and clear cell carcinoma, and the age of diagnosis decreased from sixty to fifty years old in the three decades. Patients with mucinous, endometrioid, or clear cell carcinoma had better long-term survival than patients with serous carcinoma (log rank test, p<0.001). Patients with undifferentiated carcinoma or carcinosarcoma had poorer survival than those with serous carcinoma (log rank test, p<0.001). The mortality risk of age at diagnosis of 30-39 was significantly higher than that of age of 70 years or more (test for trend, p<0.001). The mortality risk decreased from the period of 1996-1999 (hazard ratio [HR], 0.90; p=0.054) to the period after 2000 (HR, 0.74; p<0.001) as compared with that from the period of 1991-1995.ConclusionAn increasing incidence and decreasing age of diagnosis in epithelial ovarian cancer patients were noted. Histological type, age of diagnosis, and treatment period were important prognostic factors for epithelial ovarian carcinoma.

The impact of perioperative packed red blood cell transfusion on survival in epithelial ovarian cancer

Objective: Perioperative red blood cell transfusion (PRBCT) has been implicated as a negative prognostic marker in surgical oncology. The impact of PRBCT on outcomes in epithelial ovarian cancer (EOC) has not been previously reported. We assessed whether PRBCT is an independent risk factor for recurrence and death from EOC.

Functional study of risk loci of stem cell-associated gene lin-28B and associations with disease survival outcomes in epithelial ovarian cancer

Several single-nucleotide polymorphisms (SNPs) of the stem cell-associated gene lin-28B have been identified in association with ovarian cancer and ovarian cancer-related risk factors. However, whether these SNPs are functional or might be potential biomarkers for ovarian cancer prognosis remains unknown. The purposes of this study were to investigate the functional relevance of the identified lin-28B SNPs, as well as the associations of genotype and phenotype with epithelial ovarian cancer (EOC) survival. We analyzed five SNPs and mRNA levels of lin-28B in 211 primary EOC tissues using Taqman(®) SNP genotyping assays and SYBR green-based real-time PCR, respectively. The RNA secondary structures at the region of a genome-wide association-identified intronic rs314276 were analyzed theoretically with mfold and experimentally with circular dichroism spectroscopy. We found that rs314276 was a cis-acting expression quantitative trait locus (eQTL) in both additive and dominant models, while rs7759938 and rs314277 were significant or of borderline significance in dominant models only. The rs314276 variant significantly affects RNA secondary structure. No SNPs alone were associated with patient survival. However, we found that among patients initially responding to chemotherapy, those with higher lin-28B expression had higher mortality risk (hazard ratio =3.27, 95% confidence interval: 1.63-6.56) and relapse risk (hazard ratio = 2.53, 95% confidence interval: 1.41-4.54) than those with lower expression, and these associations remained in multivariate analyses. These results suggest that rs314276 alters RNA secondary structure and thereby influences gene expression, and that lin-28B is a cancer stem cell-associated marker, which may be a pharmaceutical target in the management of EOC.

CIAPIN1 nuclear accumulation predicts poor clinical outcome in epithelial ovarian cancer

BackgroundEpithelial ovarian cancer (EOC) is an aggressive disease with poor prognosis. The expression of cytokine-induced apoptosis inhibitor 1 (CIAPIN1) correlates with the malignant progression of several cancers. However, the relationship between the subcellular localization of CIAPIN1 and clinical characteristics in EOC remains unclear.MethodsImmunohistochemistry was performed to detect CIAPIN1 expression in 108 EOC tissues. CIAPIN1 expressions in eight fresh EOC tissues were detected by Western blotting. The relationship between CIAPIN1 subcellular expression and patients’ clinicopathological features, including prognosis, was evaluated. Immunohistochemistry and immunofluorescence were employed to assess the CIAPIN1 subcellular localization in the EOC cell lines A2780 and HO8910. In addition, all patients were followed up to assess the prognostic value of CIAPIN1 in patients with EOC.ResultsCIAPIN1 is highly expressed in EOC, but is present at low levels in paired non-cancerous ovarian epithelial tissues. The results of Western blotting were in accordance with the immunohistochemical results. Poor differentiation of the tumors and EOC cell lines correlated with higher levels of CIAPIN1 nuclear expression. CIAPIN1 nuclear expression significantly correlated with the Federation International of Gynecology and Obstetrics (FIGO) stage and histological differentiation (P = 0.034 and P < 0.0001, respectively). Moreover, nuclear localization of CIAPIN1 was selected as an unfavorable prognostic factor by both univariate and multivariate analyses ( P < 0.001). However, no significant correlations were observed between cytoplasmic localization of CIAPIN1 and clinicopathological parameters.ConclusionsCIAPIN1 might play a crucial role in the differentiation of EOC cells. Elevated expression of nuclear CIAPIN1 negatively correlated with the survival of EOC patients, suggesting that nuclear CIAPIN1 might serve as a prognostic biomarker for EOC patients.

BRCA mutations and outcome in epithelial ovarian cancer (EOC): Experience in ethnically diverse groups.

5078 Background: EOC patients with BRCA mutations have been reported to have better prognosis than non-hereditary (NH) matched cases, an advantage shown especially in the Ashkenazi-Jewish (AJ) population. We have analyzed our experience in our ethnically diverse patient cohort from NYC, Israel and Italy. Methods: A retrospective chart review of patients diagnosed with Stage IC-IV EOC between 1995-2008 at the NYU Cancer Institute, Tel Aviv Sourasky MC and Padova Clinical Cancer Centers. Out of &gt;700 patients, 183 were tested for BRCA mutations and evaluated. Results: Median age was 55.5 (range 31–83 years). Out of 183, 86 are carriers of BRCA1/2 mutations and 97 tested negative, 67 and 19 are carriers of BRCA1 and BRCA2 mutation respectively. Carrier frequency in EOC population is 46% (45/97) in AJ's and 48% (41/86) in non-AJ's. AJ patients had the following BRCA1 mutations: 185delAG (29), 5382insC (5), unknown (UK) (2) and BRCA2 mutations: 6174delT (8), UK (1). Non-AJ's were divided by ethnicities into non-AJ, Caucasian, African-American, Hispanic, Middle Eastern or unknown. Non-AJ Jewish patients had BRCA1 mutations in 185delAG (7) and BRCA2 in 6174delT (1), UK (1). Non-Jewish Caucasians exhibited the widest variation of mutation types, with the following BRCA1 sites: 185delAG, K1702X (5223A&gt;T), E1373X, 3829delT, 185delAT, IVS11+1G&gt;A, 5385insC, 5083del19&gt;stop1670, 1720delAF&gt;stop536, 1806C/T&gt;Igu536Ter, del ex1a-2, cod1486ex14:4575delAstop1504, 5563G7A;Trp1815stop, 5181delGTT(Val1688del) and UK and the following BRCA2 sites: 6174delT (2), 5301insA (1), 802delAT (1), cod2960ex22:9106C/t (1), cod68ex3:432delAstop79 (1), 7408A/T;Arg2394stop (1). One African-American patient with BRCA1 at 1294del40, 1 Hispanic BRCA1 at 185delAG. OS was significantly prolonged for BRCA carriers at 93.6 months versus 63.2 months [95% CI: 44.5-91.7] (p=0.0016) for NH. Conclusions: Our data reports a wide variety of BRCA mutations in an ethnically diverse EOC population and confirms that BRCA mutations carriers have a better prognosis with a longer median survival compared to NH population. A larger cohort might manifest prognostic differences between the different types of mutations.

Abstract 4007: Different expression of AHCYL1 affecting ovarian carcinogenesis between chickens and women

Abstract S-adenosylhomocysteine hydrolase-like protein 1 (AHCYL1) is the evolutionarily conserved and ubiquitously expressed enzyme that catalyzes the reversible hydrolysis of S-adenosyl-L-homocysteine, a byproduct of the S-adenosyl-L-homomethionine-dependent methyltransferase reaction, into adenosine and homocysteine. It acts like an inositol 1,4,5-triphosphate receptor (IP3R)-binding protein (termed IP3R-binding protein released with inositol 1,4,5-triphosphate, or IRBIT) by competitively inhibiting the interaction of IP3 with IP3R. As a result, AHCYL1 regulates IP3-induced Ca2+ signaling which plays crucial roles in numerous cellular processes including gene expression and cell death. However, it is still poorly understood about the expression of AHCYL1 affecting clinical outcomes in epithelial ovarian cancer (EOC). In the current study, we identified AHCYL1 affecting ovarian carcinogenesis in chickens, the most relevant model, and investigated its prognostic value in patients with EOC. In 136 chickens, ovarian cancer was detected in 10 (7.4%). We compared the expression and localization of AHCYL1 mRNA and protein between normal and cancerous ovaries of chickens using reverse transcription polymerase chain reaction, in situ hybridization and immunohistochemistry, and AHCYL1 activation was detected in chicken and human ovarian cancer cell lines (OVCAR-3, SKOV-3 and PA-1) using immunofluorescence microscopy. Thereafter, we examined the prognostic value of AHCYL1 expression in patients with EOC by multivariate linear logistic regression and Cox’ proportional hazard. As a result, AHCYL1 mRNA was induced in cancerous, but not normal ovaries of chickens (p&amp;lt;0.01), and it was abundant only in the glandular epithelium of cancerous ovaries of chickens. AHCYL1 protein was localized predominantly to the nucleus of glandular epithelium in cancerous ovaries of chickens, and it was abundant in the nucleus of both chicken and human ovarian cancer cell lines. In 109 human patients with EOC, 14 (12.8%), 41 (37.6%) and 54 (49.6%) patients showed weak, moderate and strong expression of AHCYL1 protein, respectively. However, intermediate or high expression of AHCYL1 protein was a favorable factor for overall response (adjusted OR, 7.23; 95% CI, 1.36-38.39), and for progression-free survival (PFS; adjusted HR, 0.20; 95% CI, 0.07-0.55). Conclusively, AHCYL1 may be associated with ovarian carcinogenesis in both chickens and human. In contrast to AHCYL1 expression associated with ovarian carcinogenesis in chickens, it is expected to play a role as tumor suppressor gene in human EOC because a higher expression of AHYCL1 was related with better OR and PFS. Finally, the functional role of AHCYL1 showing different expression in ovarian carcinogenesis between chickens and women should be further investigated by more relevant studies. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 4007. doi:1538-7445.AM2012-4007

Abstract 2981: Association of a BRCAness profile with outcome and molecular aberrations involving homologous recombination in the TCGA ovarian cancer dataset

Abstract A subset of sporadic epithelial ovarian cancer (EOCs) may harbor a “BRCAness” phenotype characterized by improved outcome and enhanced responsiveness to platinum analogues and PARP inhibitors, similar to their BRCA1/2 mutated counterparts. This BRCAness phenotype may be due, in part, to defective homologous recombination (HR) related to various mechanisms, including BRCA1 promoter hypermethylation, somatic mutation of BRCA1/2 genes, or loss of function mutations in other HR pathway genes. We recently defined a gene expression profile of BRCAness that correlates with chemotherapy response and outcome in EOC. Here, we used The Cancer Genome Atlas (TCGA) EOC dataset to evaluate the association of the BRCAness profile with outcome, chemotherapy response and specific molecular aberrations that may underlie defective HR. We accessed data from 265 advanced stage high grade serous EOCs for which there was available gene expression, DNA copy number, promoter methylation and whole-exome DNA sequencing information. Patients were characterized as having a BRCAness phenotype (BL profile) or not (NBL profile) based on our BRCAness signature. BL patients were associated with improved median overall survival (OS) compared to NBL patients (59 vs 41 months respectively, log-rank p=0.008). Multivariable analysis demonstrated that the BRCAness profile maintained an independent association with OS (HR=1.72, p=0.024). BL patients had a longer median platinum free interval compared to NBL patients (17 vs 11 months, p=0.024) and improved median disease free survival (18 vs 14 months, p=0.055). BRCAness profile was associated with molecular events affecting BRCA1/2 function such as BRCA1/2 mutations, BRCA1 promoter hypermethylation and EMSY amplification (47% in BL patients vs 27% in NBL patients, two-sided Fisher's exact p=0.007). Furthermore, BL patients had higher frequency of homozygous PTEN deletion compared to NBL patients but this did not reach statistical significance (12% vs 6% respectively, two-sided Fisher's exact p=0.14). Conversely, BRCAness profile was not associated with molecular events affecting the function of other Fanconi Anemia (FA) genes (FANCA/B/C/D2/E/F/G/I/J/L/M, PALB2) or DNA damage response genes involved in HR (ATM, ATR, CHEK1, CHEK2) although the overall incidence of these molecular events was very low (5% and 3% respectively). In conclusion, the BRCAness profile may identify patients with improved outcome, responsiveness to chemotherapy, and those who harbor certain molecular aberrations involving HR. Efforts to improve the predictive ability of the BRCAness profile using gene expression data from the TCGA dataset are underway. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 2981. doi:1538-7445.AM2012-2981

A KRAS variant is a biomarker of poor outcome, platinum chemotherapy resistance and a potential target for therapy in ovarian cancer

Germ-line variants in the 3′ untranslated region (3′UTR) of cancer genes disrupting microRNA (miRNA) regulation have recently been associated with cancer risk. A variant in the 3′UTR of the KRAS oncogene, referred to as the KRAS-variant, is associated with both cancer risk and altered tumor biology. Here we test the hypothesis that the KRAS-variant can act as a biomarker of outcome in epithelial ovarian cancer (EOC), and investigate the cause of altered outcome in KRAS-variant positive EOC patients. As this variant appears to be associated with tumor biology, we additionally test the hypothesis that this variant can be directly targeted to impact cell survival.EOC patients with complete clinical data were genotyped for the KRAS-variant and analyzed for outcome (n=536), response to neoadjuvant chemotherapy (n=125), and platinum resistance (n=306). Outcome was separately analyzed for women with known BRCA mutations (n=79). Gene expression was analyzed on a subset of tumors with available tissue. Cell lines were employed to confirm altered sensitivity to chemotherapy with the KRAS-variant. The KRAS-variant was directly targeted through siRNA/miRNA oligonucleotides in cell lines and survival was measured.Post-menopausal EOC patients with the KRAS-variant were significantly more likely to die of ovarian cancer by multivariate analysis (HR=1.67, 95% CI=1.09–2.57, p=0.019, n=279). Possibly explaining this finding, EOC patients with the KRAS-variant were significantly more likely to be platinum resistant (OR=3.18, CI=1.31–7.72, p=0.0106, n=291). Additionally, direct targeting of the KRAS-variant led to a significant reduction in EOC cell growth and survival in vitro.These findings confirm the importance of the KRAS-variant in EOC, and indicate that the KRAS-variant is a biomarker of poor outcome in EOC likely due to platinum resistance. In addition, this work supports the hypothesis that these tumors have continued dependence on such 3′UTR lesions, and that direct targeting may be a viable future treatment approach.

Abstract PL05-04: Epigenetic marks as biomarkers and their mechanisms of maintenance as targets in ovarian cancer.

Abstract PL05-04: Epigenetic marks as biomarkers and their mechanisms of maintenance as targets in ovarian cancer.

RBM3-Regulated Genes Promote DNA Integrity and Affect Clinical Outcome in Epithelial Ovarian Cancer

The RNA-binding motif protein 3 (RBM3) was initially discovered as a putative cancer biomarker based on its differential expression in various cancer forms in the Human Protein Atlas (HPA). We previously reported an association between high expression of RBM3 and prolonged survival in breast and epithelial ovarian cancer (EOC). Because the function of RBM3 has not been fully elucidated, the aim of this study was to use gene set enrichment analysis to identify the underlying biologic processes associated with RBM3 expression in a previously analyzed EOC cohort (cohort 1, n = 267). This revealed an association between RBM3 expression and several cellular processes involved in the maintenance of DNA integrity. RBM3-regulated genes were subsequently screened in the HPA to select for putative prognostic markers, and candidate proteins were analyzed in the ovarian cancer cell line A2780, whereby an up-regulation of Chk1, Chk2, and MCM3 was demonstrated in siRBM3-treated cells compared to controls. The prognostic value of these markers was assessed at the messenger RNA level in cohort 1 and the protein level in an independent EOC cohort (cohort 2, n = 154). High expression levels of Chk1, Chk2, and MCM3 were associated with a significantly shorter survival in both cohorts, and phosphorylated Chk2 was an adverse prognostic marker in cohort 2. These results uncover a putative role for RBM3 in DNA damage response, which might, in part, explain its cisplatin-sensitizing properties and good prognostic value in EOC. Furthermore, it is demonstrated that Chk1, Chk2, and MCM3 are poor prognostic markers in EOC.

MicroRNA let-7a: A potential marker for selection of paclitaxel in ovarian cancer management

Objectives Let-7 is a family of small non-coding RNAs regulating the expression of many genes that control important cellular activities. Let-7 is shown in vitro to sensitize cancer cells to platinum, but induce ovarian cancer resistance to paclitaxel. This study aims to investigate the effect of let-7a expression on survival outcomes of epithelial ovarian cancer (EOC) patients treated with different chemotherapy. Methods Let-7a expression was measured with qRT-PCR in ovarian tumors of 178 EOC patients who received platinum-based chemotherapy with and without paclitaxel after surgery. Survival analysis was performed to assess the effects of let-7a and chemotherapy on disease outcomes. Results Let-7a expression was detectable in the EOC samples, but the expression was not associated with disease stage, tumor grade, histology and debulking results. Patients who responded to platinum with paclitaxel had significantly lower let-7a than those who did not. Survival analyses showed that patients with high let-7a had better survival compared to those with low let-7a when they were treated with platinum without paclitaxel. The hazards ratios (HRs) for death and disease progression were 0.52 (95% CI: 0.29–0.96) and 0.48 (0.26–0.89) for high let-7a when compared to low let-7a, respectively. However, when patients were treated with platinum and paclitaxel, high let-7a was associated with worse progression-free and overall survival. The HRs for death and disease progression were 3.87 (95% CI: 1.28–11.66) and 3.48 (95% CI: 1.25–9.67) for high let-7a when compared to low let-7a, respectively. Further studies showed that among patients with low let-7a, those treated with paclitaxel in addition to platinum survived better than those treated without paclitaxel [adjusted-HRs were 0.31 (95% CI: 0.15–0.66) for death and 0.40 (95% CI: 0.22–0.75) for disease], while among those with high let-7a, the two types of treatment made no difference in patient survival. Conclusions The study suggests that the beneficial impact of the addition of paclitaxel on EOC survival was significantly linked to let-7a levels, and that miRNAs such as let-7a may be a useful marker for selection of chemotherapeutic agents in EOC management.

Polyfunctional T-Cell Responses Are Disrupted by the Ovarian Cancer Ascites Environment and Only Partially Restored by Clinically Relevant Cytokines

BackgroundHost T-cell responses are associated with favorable outcomes in epithelial ovarian cancer (EOC), but it remains unclear how best to promote these responses in patients. Toward this goal, we evaluated a panel of clinically relevant cytokines for the ability to enhance multiple T-cell effector functions (polyfunctionality) in the native tumor environment.Methodology/Principal FindingsExperiments were performed with resident CD8+ and CD4+ T cells in bulk ascites cell preparations from high-grade serous EOC patients. T cells were stimulated with α-CD3 in the presence of 100% autologous ascites fluid with or without exogenous IL-2, IL-12, IL-18 or IL-21, alone or in combination. T-cell proliferation (Ki-67) and function (IFN-γ, TNF-α, IL-2, CCL4, and CD107a expression) were assessed by multi-parameter flow cytometry. In parallel, 27 cytokines were measured in culture supernatants. While ascites fluid had variable effects on CD8+ and CD4+ T-cell proliferation, it inhibited T-cell function in most patient samples, with CD107a, IFN-γ, and CCL4 showing the greatest inhibition. This was accompanied by reduced levels of IL-1β, IL-1ra, IL-9, IL-17, G-CSF, GM-CSF, Mip-1α, PDGF-bb, and bFGF in culture supernatants. T-cell proliferation was enhanced by exogenous IL-2, but other T-cell functions were largely unaffected by single cytokines. The combination of IL-2 with cytokines engaging complementary signaling pathways, in particular IL-12 and IL-18, enhanced expression of IFN-γ, TNF-α, and CCL4 in all patient samples by promoting polyfunctional T-cell responses. Despite this, other functional parameters generally remained inhibited.Conclusions/SignificanceThe EOC ascites environment disrupts multiple T-cell functions, and exogenous cytokines engaging diverse signaling pathways only partially reverse these effects. Our results may explain the limited efficacy of cytokine therapies for EOC to date. Full restoration of T-cell function will require activation of signaling pathways beyond those engaged by IL-2, IL-12, IL-18, and IL-21.