Ovarian cancer susceptibility alleles and risk of ovarian cancer in BRCA1 and BRCA2 mutation carriers

The association between TIPARP gene polymorphisms rs2665390 and ovarian cancer susceptibility

Ovarian cancer is taken as the most typical malignancy among women and the ninth most typical cancer in Iran. Predictive tools are of great importance as ovarian cancer is usually detected in patients at later stages of the disease. In other countries, the TIPARP gene rs2665390 has been reported to be pertinent to ovarian cancer as a risk factor. This study aims to examine if this polymorphism pertains to the risk of ovarian cancer to diagnose suitable biomarkers in the Iranian population. Method: In the present case-control piliot study, peripheral blood samples were gathered from 60 control subjects and 60 patients with ovarian cancer. The gene was determined by Tetra ARMS PCR after DNA extraction. Tetra ARMS PCR is a flexible, rapid, and cost-effective method to detect allele-specific DNA polymorphisms. The data were analyzed by chi-square test. Results: The results indicated that there was a significant association between the T/T and C/C genotypes distribution and C and T allele in ovarian cancer for rs2665390 polymorphism in the two populations. In addition, significant correlations were observed in patients with the (T/T) genotype (p = 0.0048) as frequencies of ovarian cancer decreased. Discussion & Conclusions: Based on the results, rs2665390 polymorphism of TiPARP gene might be pertained to the susceptibility of ovarian cancer in the Iranian pilot population, which can be used as a suitable biomarker for the population and help physicians with their predictions. However, more studies need to be conducted in this area to broaden our horizons on this issue.

Prophylactic Radical Fimbriectomy with Delayed Oophorectomy in Women with a High Risk of Developing an Ovarian Carcinoma: Results of a Prospective National Pilot Study

Risk-reducing salpingo-oophorectomy is the gold standard for the prophylaxis of ovarian cancer in high-risk women. Due to significant adverse effects, 20-30% of women delay or refuse early oophorectomy. This prospective pilot study (NCT01608074) aimed to assess the efficacy of radical fimbriectomy followed by a delayed oophorectomy in preventing ovarian and pelvic invasive cancer (the primary endpoint) and to evaluate the safety of both procedures. The key eligibility criteria were pre-menopausal women ≥35 years with a high risk of ovarian cancer who refused a risk-reducing salpingo-oophorectomy. All the surgical specimens were subjected to the SEE-FIM protocol. From January 2012 to October 2014, 121 patients underwent RF, with 51 in an ambulatory setting. Occult neoplasia was found in two cases, with one tubal high-grade serous ovarian carcinoma. Two patients experienced grade 1 intraoperative complications. No early or delayed grade ≥3 post-operative complications occurred. After 7.3 years of median follow-up, no cases of pelvic invasive cancer have been noted. Three of the fifty-two patients developed de novo breast cancer. One BRCA1-mutated woman delivered twins safely. Twenty-five patients underwent menopause, including fifteen who had received chemotherapy for breast cancer, and twenty-three underwent menopause before the delayed oophorectomy, while two did not undergo a delayed oophorectomy at all. Overall, 46 women underwent a delayed oophorectomy. No abnormalities were found in any delayed oophorectomy specimens. Radical fimbriectomy followed by delayed oophorectomy appears to be a safe and well-tolerated risk-reducing approach, which avoids early menopause for patients with a high risk of breast and ovarian cancer.

Sequence kernel association test for survival outcomes in the presence of a non-susceptible fraction

In this work, we propose a single nucleotide polymorphism set association test for survival phenotypes in the presence of a non-susceptible fraction. We consider a mixture model with a logistic regression for the susceptibility indicator and a proportional hazards regression to model survival in the susceptible group. We propose a joint test to assess the significance of the genetic variant in both logistic and survival regressions simultaneously. We adopt the spirit of SKAT and conduct a variance-component test treating the genetic effects of multiple variants as random. We derive score-type test statistics, and we investigate several approaches to compute their $p$-values. The finite-sample properties of the proposed tests are assessed and compared to existing approaches by simulations and their use is illustrated through an application to ovarian cancer data from the Consortium of Investigators of Modifiers of BRCA1 and BRCA2.

Analysis of the association between the XRCC2 rs3218536 polymorphism and ovarian cancer risk

INTRODUCTION

Results conflict on the association between the XRCC2 rs3218536 polymorphism and ovarian cancer risk, despite wide-ranging investigations. This meta-analysis examines whether the XRCC2 rs3218536 polymorphism is associated with ovarian cancer risk.

MATERIAL AND METHODS

Eligible case-control studies were searched in PubMed. We therefore performed a meta-analysis of 5,802 ovarian cancer cases and 9,390 controls from 7 articles published. The strength of association between XRCC2 rs3218536 polymorphism and ovarian cancer susceptibility was calculated using pooled odds ratios (ORs) with corresponding 95% confidence intervals (CIs).

RESULTS

No statistically significant associations between XRCC2 rs3218536 polymorphism and ovarian cancer risk were found in any genetic models. However, a significant relationship with ovarian cancer risk was discovered when the high quality studies were pooled in the meta-analysis (AA vs. GG: OR = 0.59, 95% CI: 0.37-0.94, p = 0.03; GA vs. GG: OR = 0.87, 95% CI: 0.78-0.96, p = 0.009; GA + AA vs. GG: OR = 0.85, 95% CI: 0.77-0.94, p = 0.003; AA vs. GG + GA: OR = 0.60, 95% CI: 0.38-0.95, p = 0.03).

CONCLUSIONS

This meta-analysis shows that the XRCC2 rs3218536 polymorphism was associated with ovarian cancer risk overall for high quality studies. Non-Caucasian groups and high quality studies should be further studied.

Relationship between p-cofilin and cisplatin resistance in patients with ovarian cancer and the role of p-cofilin in prognosis

OBJECTIVE

This study aims to determine the correlation between p-cofilin expression and cisplatin resistance in patients with ovarian cancer, and also to investigate the role of p-cofilin in prognosis.

PATIENTS AND METHODS

The ovarian cancer cell line A2780/DDP resistant to cisplatin was prepared. The cell resistance to cisplatin was measured via MTT assay. The cell invasion capacity was identified via Transwell assay. The mRNA expression and protein level was evaluated via semi-quantitative PCR and Western blot, respectively. The tumor tissues of patients with cisplatin-resistant ovarian cancer were collected. The relationship between prognosis and p-cofilin expression was analyzed.

RESULTS

The growth rate of A2780 was similar to that of A2780/DDP. The sensitivity of A2780 to cisplatin was significantly higher than that of A2780/DDP (p< 0.01). The migration capacity of A2780/DDP was significantly increased compared to that of A2780 (p< 0.01), indicating that the cisplatin-resistant cell lines were successfully constructed. Both CFL1 mRNA level and p-cofilin level in A2780/DDP was significantly higher than that in A2780 (p< 0.01). The p-cofilin level in cancer tissues in patients with cisplatin-resistant ovarian cancer was significantly higher than that in patients with cisplatin-sensitive ovarian cancer (p< 0.01). The cisplatin resistance was positively correlated with the p-cofilin expression level (r= 0.802, p= 0.023). The survival time of patients with normal or low level of p-cofilin was significantly longer than that of patients with high expression.

CONCLUSION

The cisplatin resistance of ovarian cancer is closely related to the expression level of p-cofilin, which affects the prognosis of patients with ovarian cancer.

Global epidemiology, risk factors, and histological types of ovarian cancers in Trinidad

Background

Ovarian cancer is the seventh most common cancer in women in the world and Trinidad and Tobago is ranked 18^th in the world with respect to the rate of occurrence. About 68% cases are diagnosed at a late stage, resulting in low survival rates. Since there is very scanty literature available on the epidemiology of ovarian cancer in the Caribbean region, this study was undertaken to assess the most common risk factors, presenting symptoms and common histological varieties in Trinidad.

Methods

A hospital-based, cross-sectional study was designed, and all the 23 diagnosed ovarian cancer cases registered during 2015-2017 were considered. Information on sociodemographics, presenting symptoms, and histological type of cancers were collected after getting the ethical approval. Of the total 23 cases, 17 cases were included in this study after ensuring completeness of data as detailed analysis of patient data was done using Microsoft Excel.

Results

The common risk factors identified were previous pregnancies, previous surgeries, and irregularities in the menstrual cycle. The commonest histological variety was granulosa tumors and the most common associated symptoms were irregular menses and abdominal pain in premenstrual women, and abdominal distention in postmenopausal women.

Conclusions

It would greatly enhance the detection rate if screening and testing for the CA-125 gene were a mandatory practice, for any patient found with more than three risk factors. The public health authorities should identify the modifiable risk factors and implement cancer reduction and health promotion activities to reduce the mortality related to ovarian cancers.

Association of p16 expression with prognosis varies across ovarian carcinoma histotypes: an Ovarian Tumor Tissue Analysis consortium study

We aimed to validate the prognostic association of p16 expression in ovarian high-grade serous carcinomas (HGSC) and to explore it in other ovarian carcinoma histotypes. p16 protein expression was assessed by clinical-grade immunohistochemistry in 6525 ovarian carcinomas including 4334 HGSC using tissue microarrays from 24 studies participating in the Ovarian Tumor Tissue Analysis consortium. p16 expression patterns were interpreted as abnormal (either overexpression referred to as block expression or absence) or normal (heterogeneous). CDKN2A (which encodes p16) mRNA expression was also analyzed in a subset (n = 2280) mostly representing HGSC (n = 2010). Association of p16 expression with overall survival (OS) was determined within histotypes as was CDKN2A expression for HGSC only. p16 block expression was most frequent in HGSC (56%) but neither protein nor mRNA expression was associated with OS. However, relative to heterogeneous expression, block expression was associated with shorter OS in endometriosis-associated carcinomas, clear cell [hazard ratio (HR): 2.02, 95% confidence (CI) 1.47-2.77, p < 0.001] and endometrioid (HR: 1.88, 95% CI 1.30-2.75, p = 0.004), while absence was associated with shorter OS in low-grade serous carcinomas (HR: 2.95, 95% CI 1.61-5.38, p = 0.001). Absence was most frequent in mucinous carcinoma (50%), and was not associated with OS in this histotype. The prognostic value of p16 expression is histotype-specific and pattern dependent. We provide definitive evidence against an association of p16 expression with survival in ovarian HGSC as previously suggested. Block expression of p16 in clear cell and endometrioid carcinoma should be further validated as a prognostic marker, and absence in low-grade serous carcinoma justifies CDK4 inhibition.

Association of p16 expression with prognosis varies across ovarian carcinoma histotypes: an Ovarian Tumor Tissue Analysis consortium study

We aimed to validate the prognostic association of p16 expression in ovarian high-grade serous carcinomas (HGSC) and to explore it in other ovarian carcinoma histotypes. p16 protein expression was assessed by clinical-grade immunohistochemistry in 6525 ovarian carcinomas including 4334 HGSC using tissue microarrays from 24 studies participating in the Ovarian Tumor Tissue Analysis consortium. p16 expression patterns were interpreted as abnormal (either overexpression referred to as block expression or absence) or normal (heterogeneous). CDKN2A (which encodes p16) mRNA expression was also analyzed in a subset (n = 2280) mostly representing HGSC (n = 2010). Association of p16 expression with overall survival (OS) was determined within histotypes as was CDKN2A expression for HGSC only. p16 block expression was most frequent in HGSC (56%) but neither protein nor mRNA expression was associated with OS. However, relative to heterogeneous expression, block expression was associated with shorter OS in endometriosis-associated carcinomas, clear cell [hazard ratio (HR): 2.02, 95% confidence (CI) 1.47-2.77, p < 0.001] and endometrioid (HR: 1.88, 95% CI 1.30-2.75, p = 0.004), while absence was associated with shorter OS in low-grade serous carcinomas (HR: 2.95, 95% CI 1.61-5.38, p = 0.001). Absence was most frequent in mucinous carcinoma (50%), and was not associated with OS in this histotype. The prognostic value of p16 expression is histotype-specific and pattern dependent. We provide definitive evidence against an association of p16 expression with survival in ovarian HGSC as previously suggested. Block expression of p16 in clear cell and endometrioid carcinoma should be further validated as a prognostic marker, and absence in low-grade serous carcinoma justifies CDK4 inhibition.

Association of p16 expression with prognosis varies across ovarian carcinoma histotypes: an Ovarian Tumor Tissue Analysis consortium study

We aimed to validate the prognostic association of p16 expression in ovarian high-grade serous carcinomas (HGSC) and to explore it in other ovarian carcinoma histotypes. p16 protein expression was assessed by clinical-grade immunohistochemistry in 6525 ovarian carcinomas including 4334 HGSC using tissue microarrays from 24 studies participating in the Ovarian Tumor Tissue Analysis consortium. p16 expression patterns were interpreted as abnormal (either overexpression referred to as block expression or absence) or normal (heterogeneous). CDKN2A (which encodes p16) mRNA expression was also analyzed in a subset (n = 2280) mostly representing HGSC (n = 2010). Association of p16 expression with overall survival (OS) was determined within histotypes as was CDKN2A expression for HGSC only. p16 block expression was most frequent in HGSC (56%) but neither protein nor mRNA expression was associated with OS. However, relative to heterogeneous expression, block expression was associated with shorter OS in endometriosis-associated carcinomas, clear cell [hazard ratio (HR): 2.02, 95% confidence (CI) 1.47-2.77, p < 0.001] and endometrioid (HR: 1.88, 95% CI 1.30-2.75, p = 0.004), while absence was associated with shorter OS in low-grade serous carcinomas (HR: 2.95, 95% CI 1.61-5.38, p = 0.001). Absence was most frequent in mucinous carcinoma (50%), and was not associated with OS in this histotype. The prognostic value of p16 expression is histotype-specific and pattern dependent. We provide definitive evidence against an association of p16 expression with survival in ovarian HGSC as previously suggested. Block expression of p16 in clear cell and endometrioid carcinoma should be further validated as a prognostic marker, and absence in low-grade serous carcinoma justifies CDK4 inhibition.

Development of a Tool to Guide Parents Carrying a BRCA1/2 Mutation Share Genetic Results with Underage Children

Although most parents carrying a BRCA1/2 genetic mutation share their test result with their underage children, they report needing support to decide if, when, and how to share risk information and what reactions to expect from their children. We developed a tool to guide parents carrying a BRCA1/2 mutation share their genetic result with underage children. Here, we report on the development of this tool using a qualitative methodology. A tool prototype was developed based on the International Patient Decision Aids Standards Collaboration framework. Content was assessed using feedback from focus groups, individual interviews, and a 12-item reading grid. Participants were nine BRCA1/2 mutation carriers with underage children and three cancer genetics health professionals. Thematic content analysis was conducted on interview transcripts. The tool was developed using an iterative process until saturation of data. An independent advisory committee was involved in all steps of tool development until reaching consensus. Rather than a decision aid per se (to communicate or not), the parents wanted a more comprehensive tool to help them communicate genetic test result to their children. To meet parents' needs, a communication guidance booklet was developed, setting out the pros and cons of communication, steps to prepare sharing the test result, communication tips, and parents' testimonies. This communication tool responds to a significant unmet need faced by parents carrying a genetic predisposition to cancer. Future studies are needed to assess how the information from the parent's genetic test result impacts the child's development, health behaviors, and relationship with the parent.

Delivering widespread BRCA testing and PARP inhibition to patients with ovarian cancer

The treatment of patients with ovarian cancer is rapidly changing following the success of poly [ADP-ribose] polymerase (PARP) inhibitors in clinical trials. Olaparib is the first PARP inhibitor to be approved by the EMA and FDA for BRCA-mutated ovarian cancer. Germ line BRCA mutation status is now established as a predictive biomarker of potential benefit from treatment with a PARP inhibitor; therefore, knowledge of the BRCA status of an individual patient with ovarian cancer is essential, in order to guide treatment decisions. BRCA testing was previously offered only to women with a family or personal history of breast and/or ovarian cancer; however, almost 20% of women with high-grade serous ovarian cancer are now recognized to harbour a germ line BRCA mutation, and of these, >40% might not have a family history of cancer and would not have received BRCA testing. A strategy to enable more widespread implementation of BRCA testing in routine care is, therefore, necessary. In this Review, we summarize data from key clinical trials of PARP inhibitors and discuss how to integrate these agents into the current treatment landscape of ovarian cancer. The validity of germ line BRCA testing and other promising biomarkers of homologous-recombination deficiency will also be discussed.

Modifiers of breast and ovarian cancer risks for BRCA1 and BRCA2 mutation carriers

Pathogenic mutations in BRCA1 and BRCA2 are associated with high risks of breast and ovarian cancer. However, penetrance estimates for mutation carriers have been found to vary substantially between studies, and the observed differences in risk are consistent with the hypothesis that genetic and environmental factors modify cancer risks for women with these mutations. Direct evidence that this is the case has emerged in the past decade, through large-scale international collaborative efforts. Here, we describe the methodological challenges in the identification and characterisation of these risk-modifying factors, review the latest evidence on genetic and lifestyle/hormonal risk factors that modify breast and ovarian cancer risks for women with BRCA1 and BRCA2 mutations and outline the implications of these findings for cancer risk prediction. We also review the unresolved issues in this area of research and identify strategies of clinical implementation so that women with BRCA1 and BRCA2 mutations are no longer counselled on the basis of 'average' risk estimates.

Sam68 is Overexpressed in Epithelial Ovarian Cancer and Promotes Tumor Cell Proliferation

BACKGROUND Epithelial ovarian cancer (EOC) is the deadliest gynecological malignancy, and evidence is accumulating on how molecular markers may be associated with the origin and process of EOC. Sam68 (Src-associated in mitosis, of 68 kD), is a K homology domain RNA-binding protein that has been investigated as a risk factor in multiple types of tumors. The aim of the present study was to investigate the contribution of the Sam68 gene in the pathogenesis of EOC. MATERIAL AND METHODS Western blot assay and real-time quantitative PCR methods were performed to examine Sam68 expression in EOC tissue specimens. The association of Sam68 expression with clinic-pathologic variables of EOC was evaluated. Then gain-of-function and loss-of-function strategies were adopted to examine the regulation of Sam68 on the proliferation of EOC OVCAR-3 cells using CCK-8 and colony forming assays. RESULTS Sam68 was overexpressed in both mRNA and protein levels in EOC tumor tissue (n=152) in an association with malignant factors of EOC such as International Federation of Gynecology and Obstetrics (FIGO) stage, residual tumor size (cm), histological grade, and lymph node metastasis. In vitro results demonstrated that Sam68 overexpression was upregulated while Sam68 knockdown downregulated the proliferation of EOC OVCAR-3 cells via regulation of cell growth and colony formation. CONCLUSIONS Sam68 was overexpressed in EOC tissue in association with such cancer malignant factors of FIGO stage, histological grade, and lymph node metastasis, and also positively regulated the proliferation of EOC cells. Our research suggests that Sam68 might accelerate cell cycle progression, and present as a prognostic marker for EOC.

Analysis of the Association of Matrix Metalloproteinase-1 Gene Promoter (rs1799750) Polymorphism and Risk of Ovarian Cancer

OBJECTIVE

Studies investigating the association between matrix metalloproteinase-1 (MMP1) gene promoter 1607-base pair (bp) polymorphism and ovarian cancer risk have yielded conflicting results.

METHODS

We therefore carried out a meta-analysis of 754 ovarian cancer cases and 1184 controls from 5 published case-control studies. The strength of the association between MMP1 1607-bp polymorphism and ovarian cancer susceptibility was calculated using pooled odds ratios (ORs) with corresponding 95% confidence intervals (CIs).

RESULTS

The results suggest that no statistically significant associations exist between MMP1 1607-bp polymorphisms and ovarian cancer risk in all 4 genetic models (2G2G vs 1G1G: OR, 1.08; 95% CI, 0.81-1.43; P = 0.23; 1G2G vs 1G1G: OR, 1.06; 95% CI, 0.82-1.36; P = 0.15; 1G2G + 2G2G vs 1G1G: OR, 1.05; 95% CI, 0.83-1.34; P = 0.16; 2G2G vs 1G1G + 1G2G: OR, 0.98; 95% CI, 0.80-1.20; P = 0.84).

CONCLUSIONS

In summary, this meta-analysis showed that the MMP1 1607-bp polymorphism is not associated with ovarian cancer risk.

Ongoing Use of Data and Specimens From National Cancer Institute-Sponsored Cancer Prevention Clinical Trials in the Community Clinical Oncology Program

Large cancer prevention trials provide opportunities to collect a wide array of data and biospecimens at study entry and longitudinally, for a healthy, aging population without cancer. This provides an opportunity to use pre-diagnostic data and specimens to evaluate hypotheses about the initial development of cancer. We report on strides made by, and future possibilities for, the use of accessible biorepositories developed from precisely annotated samples obtained through large-scale National Cancer Institute (NCI)-sponsored cancer prevention clinical trials conducted by the NCI Cooperative Groups. These large cancer prevention studies, which have enrolled more than 80,000 volunteers, continue to contribute to our understanding of cancer development more than 10 years after they were closed.

The GADD45A (1506T>C) Polymorphism Is Associated with Ovarian Cancer Susceptibility and Prognosis

GADD45A (growth arrest and DNA damage 45 A) is the first stress-inducible gene identified to be a target of p53. However, no studies to date have assessed variants of the GADD45 gene and their potential relationship to tumor susceptibility. We investigated the association of the GADD45A (1506T>C) polymorphism with ovarian cancer development in 258 ovarian cancer patients and 332 age-matched healthy women as controls using sequence analysis. We found a statistically significant difference in the GADD45A (1506T>C) genotype distributions between the case and control groups (TT vs. TC vs. CC, P = 0.0021) and found that variant 1506T>C was significantly associated with an increased risk of ovarian cancer (P<0.001, OR = 1.71, 95% CI [1.28–2.29]). We observed a statistically significant effect between tumor histology (P = 0.032) and CA125 status (P = 0.021). Carrying the C allele (TC+CC) was associated with an increased risk of positive CA125 (OR = 3.20, 95% CI [1.15–8.71). Carrying the T allele (TT+TC) showed a significant correlation with both higher GADD45A mRNA expression and longer ovarian cancer RFS (relapse-free survival) and OS (overall survival). We are the first group to demonstrate that the GADD45A (1506T>C) polymorphism is associated with ovarian cancer susceptibility and prognosis. These data suggest that GADD45A (1506T>C) is a new tumor susceptibility gene and could be a useful molecular marker for assessing ovarian cancer risk and for predicting ovarian cancer patient prognosis.

A risk prediction algorithm for ovarian cancer incorporating BRCA1, BRCA2, common alleles and other familial effects

BACKGROUND

Although BRCA1 and BRCA2 mutations account for only ∼27% of the familial aggregation of ovarian cancer (OvC), no OvC risk prediction model currently exists that considers the effects of BRCA1, BRCA2 and other familial factors. Therefore, a currently unresolved problem in clinical genetics is how to counsel women with family history of OvC but no identifiable BRCA1/2 mutations.

METHODS

We used data from 1548 patients with OvC and their relatives from a population-based study, with known BRCA1/2 mutation status, to investigate OvC genetic susceptibility models, using segregation analysis methods.

RESULTS

The most parsimonious model included the effects of BRCA1/2 mutations, and the residual familial aggregation was accounted for by a polygenic component (SD 1.43, 95% CI 1.10 to 1.86), reflecting the multiplicative effects of a large number of genes with small contributions to the familial risk. We estimated that 1 in 630 individuals carries a BRCA1 mutation and 1 in 195 carries a BRCA2 mutation. We extended this model to incorporate the explicit effects of 17 common alleles that are associated with OvC risk. Based on our models, assuming all of the susceptibility genes could be identified we estimate that the half of the female population at highest genetic risk will account for 92% of all OvCs.

CONCLUSIONS

The resulting model can be used to obtain the risk of developing OvC on the basis of BRCA1/2, explicit family history and common alleles. This is the first model that accounts for all OvC familial aggregation and would be useful in the OvC genetic counselling process.

Analyze Association of BRCA2 Arg372His Polymorphism With Ovarian Cancer Risk

OBJECTIVE

Studies investigating the association between BRCA2 Arg372His polymorphism and ovarian cancer risks have yielded conflicting results.

METHODS

We carried out a meta-analysis of 8488 ovarian cancer cases and 14,510 controls from 7 case-control studies in 5 articles published. The association between BRCA2 Arg372His polymorphism and ovarian cancer susceptibility was calculated using pooled odds ratios (ORs) appropriately derived from fixed effects models.

RESULTS

There were no significant associations between BRCA2 Arg372His polymorphisms and ovarian cancer risk in overall comparisons in all genetic models (HH vs NN: OR, 1.06; 95% confidence interval [95% CI], 0.96-1.18; P = 0.25; NH vs NN: OR, 1.02; 95% CI, 0.96-1.07; P = 0.6; NH + HH vs NN: OR, 1.01; 95% CI, 0.98-1.04; P = 0.42; HH vs NN + NH: OR, 1.06; 95% CI, 0.95-1.17; P = 0.29).

CONCLUSIONS

This meta-analysis indicates that the BRCA2 Arg372His polymorphism is not associated with ovarian cancer risk for whites. Asian and African populations should be further studied.

Identification of six new susceptibility loci for invasive epithelial ovarian cancer

Genome-wide association studies (GWAS) have identified 12 epithelial ovarian cancer (EOC) susceptibility alleles. The pattern of association at these loci is consistent in BRCA1 and BRCA2 mutation carriers who are at high risk of EOC. After imputation to 1000 Genomes Project data, we assessed associations of 11 million genetic variants with EOC risk from 15,437 cases unselected for family history and 30,845 controls and from 15,252 BRCA1 mutation carriers and 8,211 BRCA2 mutation carriers (3,096 with ovarian cancer), and we combined the results in a meta-analysis. This new study design yielded increased statistical power, leading to the discovery of six new EOC susceptibility loci. Variants at 1p36 (nearest gene, WNT4), 4q26 (SYNPO2), 9q34.2 (ABO) and 17q11.2 (ATAD5) were associated with EOC risk, and at 1p34.3 (RSPO1) and 6p22.1 (GPX6) variants were specifically associated with the serous EOC subtype, all with P < 5 × 10(-8). Incorporating these variants into risk assessment tools will improve clinical risk predictions for BRCA1 and BRCA2 mutation carriers.

Novel and recurrent BRCA2 mutations in Italian breast/ovarian cancer families widen the ovarian cancer cluster region boundaries to exons 13 and 14

Hereditary breast and ovarian cancer are mainly linked to mutations in BRCA1 and BRCA2 genes which confer a similar cumulative risk of developing breast cancer. Importantly, while BRCA2 mutation carriers generally have a lower cumulative risk for ovarian cancer, mutations clustered in the central portion of BRCA2 are associated with a higher proportion of ovarian compared with breast cancer cases. The boundaries of this ovarian cancer cluster region (OCCR) have been tentatively defined within a 3.3 kb region of BRCA2 exon 11, and herein, we reassessed these boundaries using our series of Italian breast/ovarian cancer families. We used direct sequencing to investigate BRCA mutations in 367 breast/ovarian cancer families. We also studied the association between the location of the mutations and the ovarian cancer phenotype in our cohort of BRCA2-mutated families. We observed the novel c.7309_7309delA frameshift mutation and the c.7007G>A deleterious mutation in BRCA2 exons 14 and 13, respectively, in five independent Italian families characterized by a high proportion of ovarian cancer cases. Of note, a significantly higher proportion of ovarian versus breast cancer cases was associated not only with mutations in the previously defined OCCR (OR = 5.91; p = 0.004), but also with the exon 13-14 region (OR = 7.37; p = 0.001) in our BRCA2-mutated families. Our data provide initial evidence for a novel putative OCCR in BRCA2 exons 13-14.

Absence of BRCA/FMR1 correlations in women with ovarian cancers

Previously reported findings in Austrian BRCA1/2 mutation carriers suggested a possible dependency of embryos with BRCA1/2 mutations on so-called low alleles of the fragile X mental retardation 1 (FMR1) gene, characterized by less than 26 CGG repeats (CGG(n<26)). The hypothesis arose from a study reporting highly statistically significant enrichment of low FMR1 alleles, significantly exceeding low allele prevalence in a general population, suggesting embryo lethality of BRCA1/2 mutations, "rescued" by presence of low FMR1 alleles. Such a dependency would also offer an explanation for the so-called "BRCA-paradox," characterized by BRCA1/2 deficient embryonic tissues being anti-proliferative (thereby potentially causing embryo-lethality) but proliferative in malignant tumors, including breast and ovarian cancers. Follow up investigations by other investigators, however, at most demonstrated trends towards enrichment but, mostly, no enrichment at all, raising questions about the original observation and hypothesis. We in this study, therefore, investigated CGGn of the FMR1 gene of 86 anonymized DNA samples from women with various forms of ovarian cancer, and were unable to demonstrate differences in prevalence of low FMR1 alleles either between positive and negative ovarian cancer patients for BRCA1/2 or between ovarian cancer patients and reported rates in non-cancer populations. This raises further questions about a suggested dependency between BRCA1/2 and FMR1, but also raises the possibility that investigated Austrian BRCA1/2 carrier populations differ from those in other countries. Either only selected BRCA1/2 mutations, therefore, interact with low FMR1 alleles or the Austrian data reflect only coincidental observations.

Modifiers of cancer risk in BRCA1 and BRCA2 mutation carriers: systematic review and meta-analysis

BACKGROUND

There is substantial variability in cancer risk in women who have inherited a BRCA1 or BRCA2 (BRCA1/2) mutation. Numerous factors have been hypothesized to modify these risks, but studies are of variable quality, and it remains unclear which of these may be of value in clinical risk assessment.

METHODS

PubMed and Web of Science databases were searched for articles published through September 2013. Fixed effects meta-analysis was done using the hazard ratios and/or odds ratios to estimate the pooled effect estimates (ES) and 95% confidence intervals (CIs) to identify factors that are associated with cancer risk modification in BRCA1/2 mutation carriers.

RESULTS

We identified 44 nonoverlapping studies that met predefined quality criteria. Sufficient evidence is available to make clinically relevant inferences about a number of cancer risk modifiers. The only variable examined that produced a probable association was late age at first live birth, a meta-analysis showed a decrease in the risk of breast cancer in BRCA1 mutation carriers with women aged 30 years or older vs. women younger than 30 years (ES = 0.65; 95% CI =0.42 to 0.99). The same was shown for women aged 25 to 29 years versus those aged less than 25 years (ES = 0.69; 95% CI = 0.48 to 0.99). Breastfeeding and tubal ligation were associated with reduced ovarian cancer risk in BRCA1 mutation carriers; oral contraceptives were associated with reduced risk among BRCA1/2 mutation carriers. Smoking was associated with increased breast cancer risk in BRCA2 mutation carriers only.

CONCLUSIONS

Data assessing many potential risk modifiers are inadequate, and many have not been externally validated. Although additional studies are required to confirm some associations, sufficient information is available for some risk factors to be used in risk counseling or lifestyle modification to minimize cancer risk in BRCA1/2 mutation carriers

Analyzing association of the XRCC3 gene polymorphism with ovarian cancer risk

This meta-analysis aims to examine whether the XRCC3 polymorphisms are associated with ovarian cancer risk. Eligible case-control studies were identified through search in PubMed. Pooled odds ratios (ORs) were appropriately derived from fixed effects models. We therefore performed a meta-analysis of 5,302 ovarian cancer cases and 8,075 controls from 4 published articles and 8 case-control studies for 3 SNPs of XRCC3. No statistically significant associations between XRCC3 rs861539 polymorphisms and ovarian cancer risk were observed in any genetic models. For XRCC3 rs1799794 polymorphisms, we observed a statistically significant correlation with ovarian cancer risk using the homozygote comparison (T2T2 versus T1T1: OR = 0.70, 95% CI = 0.54–0.90, P = 0.005), heterozygote comparison (T1T2 versus T1T1: OR = 1.10, 95% CI = 1.00–1.21, P = 0.04), and the recessive genetic model (T2T2 versus T1T1+T1T2: OR = 0.67, 95% CI = 0.52–0.87, P = 0.002). For XRCC3 rs1799796 polymorphisms, we also observed a statistically significant correlation with ovarian cancer risk using the heterozygote comparison (T1T2 versus T1T1: OR = 0.91, 95% CI = 0.83–0.99, P = 0.04). In conclusion, this meta-analysis shows that the XRCC3 were associated with ovarian cancer risk overall for Caucasians. Asian and African populations should be further studied.

Challenging and complex decisions in the management of the BRCA mutation carrier

Women afflicted by the hereditary breast and ovarian cancer syndrome face complex decisions regarding medical interventions aimed at reducing their risk of ovarian and breast cancer, interventions which in turn may interfere with their fertility and cause early menopause. This review addresses selected topics of importance and controversy in the management of the BRCA mutation carrier, such as psychological well-being and quality of life, breast and ovarian cancer screening, risk-reducing interventions for breast cancer and ovarian cancer, the issue of hysterectomy at the time of the risk-reducing salpingo-oophorectomy, health consequences of early surgical menopause, and safety of hormonal therapy after oophorectomy. The information presented is based on an extensive review of the literature on the selected topics and on the expertise of our multidisciplinary team.

Analyze association of the progesterone receptor gene polymorphism PROGINS with ovarian cancer risk

Results conflict on the association between progesterone receptor gene (PRG) polymorphism PROGINS and ovarian cancer risk, despite wide-ranging investigations. We therefore performed a meta-analysis of 4,285 ovarian cancer cases and 6,257 controls from 11 published case-control studies. The strength of association between PROGINS polymorphism and ovarian cancer susceptibility was assessed using pooled odds ratios (ORs) with corresponding 95 % confidence intervals (CIs). The results suggest no significant associations exist between PROGINS polymorphisms and ovarian cancer risk in overall comparisons in all genetic models (T2T2 vs. T1T1: OR = 1.37, 95 % CI = 0.89-2.12, P = 0.15; T1T2 vs. T1T1:OR = 1.09, 95 % CI = 0.88-1.35, P = 0.41; T1T2 + T2T2 vs. T1T1:OR = 1.15, 95 % CI = 0.94-1.40, P = 0.17; T2T2 vs. T1 T1 + T1T2:OR = 1.34, 95 % CI = 0.87-2.07, P = 0.18). In conclusion, the results of this meta-analysis indicate that the PRG polymorphism PROGINS is not associated with ovarian cancer risk when multiple ethnic groups or regions were considered overall.

Genome-wide association study in BRCA1 mutation carriers identifies novel loci associated with breast and ovarian cancer risk

BRCA1-associated breast and ovarian cancer risks can be modified by common genetic variants. To identify further cancer risk-modifying loci, we performed a multi-stage GWAS of 11,705 BRCA1 carriers (of whom 5,920 were diagnosed with breast and 1,839 were diagnosed with ovarian cancer), with a further replication in an additional sample of 2,646 BRCA1 carriers. We identified a novel breast cancer risk modifier locus at 1q32 for BRCA1 carriers (rs2290854, P = 2.7 × 10(-8), HR = 1.14, 95% CI: 1.09-1.20). In addition, we identified two novel ovarian cancer risk modifier loci: 17q21.31 (rs17631303, P = 1.4 × 10(-8), HR = 1.27, 95% CI: 1.17-1.38) and 4q32.3 (rs4691139, P = 3.4 × 10(-8), HR = 1.20, 95% CI: 1.17-1.38). The 4q32.3 locus was not associated with ovarian cancer risk in the general population or BRCA2 carriers, suggesting a BRCA1-specific association. The 17q21.31 locus was also associated with ovarian cancer risk in 8,211 BRCA2 carriers (P = 2×10(-4)). These loci may lead to an improved understanding of the etiology of breast and ovarian tumors in BRCA1 carriers. Based on the joint distribution of the known BRCA1 breast cancer risk-modifying loci, we estimated that the breast cancer lifetime risks for the 5% of BRCA1 carriers at lowest risk are 28%-50% compared to 81%-100% for the 5% at highest risk. Similarly, based on the known ovarian cancer risk-modifying loci, the 5% of BRCA1 carriers at lowest risk have an estimated lifetime risk of developing ovarian cancer of 28% or lower, whereas the 5% at highest risk will have a risk of 63% or higher. Such differences in risk may have important implications for risk prediction and clinical management for BRCA1 carriers.

The MTDH (-470G>A) polymorphism is associated with ovarian cancer susceptibility

MTDH (metadherin), an important oncogene that is widely overexpressed in various cancers, is a potential biomarker of tumor malignancy. Variants in MTDH have been associated with susceptibility to breast cancer. However, no studies assessing MTDH gene polymorphisms and their potential relationship to ovarian cancer susceptibility have been reported. Thus, we investigated the association of MTDH (-470G>A) polymorphism with ovarian cancer development in 145 ovarian cancer patients and 254 matched control subjects, using sequence analysis. We found that the MTDH (-470G>A) polymorphism was statistically correlated with ovarian cancer risk (under the additive genetic model, GG vs. GA vs AA, P = 0.042). Compared with genotypes containing the G allele (GG and GA), the AA genotype may decrease the risk of ovarian cancer (P = 0.0198, OR = 0.33, 95% CI [0.12∼0.78]). Compared with the G allele, the A allele is protective against ovarian cancer risk (P = 0.01756, OR = 0.66, 95% CI [0.46∼0.93]). Furthermore, a statistically significant association between the GG and GA+AA genotypes and the clinical stage was observed (P = 0.038). These data suggest that MTDH (-470G>A) could be a useful molecular marker for assessing ovarian cancer risk and for predicting ovarian cancer patient prognosis.