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

Current and future role of genetic screening in gynecologic malignancies

The world of hereditary cancers has seen exponential growth in recent years. While hereditary breast and ovarian cancer and Lynch syndrome account for the majority of mutations encountered by gynecologists, newly identified deleterious genetic mutations continue to be unearthed with their associated risks of malignancies. However, these advances in genetic cancer predispositions then force practitioners and their patients to confront the uncertainties of these less commonly identified mutations and the fact that there is limited evidence to guide them in expected cancer risk and appropriate risk-reduction strategies. Given the speed of information, it is imperative to involve cancer genetics experts when counseling these patients. In addition, coordination of screening and care in conjunction with specialty high-risk clinics, if available, allows for patients to have centralized management for multiple cancer risks under the guidance of physicians with experience counseling these patients. The objective of this review is to present the current literature regarding genetic mutations associated with gynecologic malignancies as well to propose screening and risk-reduction options for these high-risk patients.

Reproductive factors as risk modifiers of breast cancer in BRCA mutation carriers and high-risk non-carriers

This study was conducted to identify the role of reproductive factors as environmental modifiers for breast cancer (BC) risk in clinic-based, East-Asian BRCA1 and BRCA2 mutation carriers and non-carriers with high-risk criteria of BRCA mutations (family history (FH) of BC, early-onset BC (aged ≤40 years)). A total of 581 women who were BRCA carriers (222 BRCA1 and 359 BRCA2), 1,083 non-carriers with FH, and 886 non-carriers with early-onset BC were enrolled and interviewed to examine the reproductive factors, from 2007 to 2014. The hazard ratio (HR) and its 95% confidence interval (CI) in the weighted Cox regression model were used to calculate the BC risk based on the reproductive factors. Earlier menarche increased BC risk by 3.49-fold in BRCA2 mutation carriers (95%CI=2.03-6.00) and 3.30-fold in non-carriers with FH (95%CI=1.73-6.34), but was insignificantly associated with BRCA1 carriers and non-carriers for early-onset BC (P-heterogeneity=0.047). Higher parity decreased BC risk in BRCA carriers and non-carriers with FH, especially in BRCA1 carriers (HR=0.27, 95% CI=0.09-0.83 for two parity; and HR=0.23, 95%CI=0.05-1.00 for ≥3 parity), but increased the early-onset BC risk (HR=4.63, 95%CI=2.56-8.51 for >3 parity, p-heterogeneity=0.045). Oral contraceptive (OC) use and longer estrogen exposure periods (≥30 years) were associated with an increased risk of early-onset BC (HR=3.99, 95%CI=1.65-9.67; HR=7.69, 95%CI=1.96-25.01), while OC use was not associated with BC risk in other groups and longer estrogen exposure had rather decreased risk for BC risk (both p-heterogeneity<0.001). Several reproductive factors as risk modifiers could heterogeneously be associated with BC among BRCA1/2 mutation carriers, non-carriers with FH, and early-onset BC non-carriers.

Genetic testing in women with breast cancer: implications for treatment

INTRODUCTION

Mutations in either the BRCA1 or BRCA2 genes are responsible for approximately 42,000 cases of breast cancer annually. Identifying these germline mutations in a woman with breast cancer is important because it can influence her immediate and long-term management and has important implications for other family members. Areas covered: This review highlights how treatment-focussed genetic testing for BRCA1 and BRCA2 mutations can potentially influence cancer treatment and secondary prevention decisions in women with breast cancer. Expert commentary: Testing women with breast cancer for BRCA1 and BRCA2 germline mutations has the potential to decrease cancer burden and improve cancer outcomes. It can help optimise surgical and systemic therapy approaches. Clinicians should actively consider whether genetic testing is appropriate for each woman with breast cancer, and if so should instigate it early in the treatment trajectory when it can most influence cancer care.

The potential contribution of dietary factors to breast cancer prevention

Breast cancer (BC), the leading cancer in women, is increasing in prevalence worldwide, concurrent with western metabolic epidemics, that is, obesity, metabolic syndrome, and diabetes, and shares major risk factors with these diseases. The corresponding potential for nutritional contributions toward BC prevention is reviewed and related to critical stages in the life cycle and their implications for carcinogenic and pathometabolic trajectories. BC initiation potentially involves diet-related pro-oxidative, inflammatory, and procarcinogenic processes, that interact through combined lipid/fatty acid peroxidation, estrogen metabolism, and related DNA-adduct/depurination/mutation formation. The pathometabolic trajectory is affected by high estrogen, insulin, and growth factor cascades and resultant accelerated proliferation/progression. Anthropometric risk factors - high birth weight, adult tallness, adiposity/BMI, and weight gain - are often reflective of these trends. A sex-based nutritional approach targets women's specific risk in western obesogenic environments, associated with increasing fatness, estrogen metabolism, n-6 : n-3 polyunsaturated fatty acid ratio, and n-6 polyunsaturated fatty acid conversion to proinflammatory/carcinogenic eicosanoids, and effects of timing of life events, for example, ages at menarche, full-term pregnancy, and menopause. Recent large-scale studies have confirmed the effectiveness of the evidence-based recommendations against BC risk, emphasizing low-energy density diets, highly nutritious plant-based regimes, physical activity, and body/abdominal adiposity management. Better understanding of dietary inter-relationships with BC, as applied to food intake, selection, combination, and processing/preparation, and recommended patterns, for example, Mediterranean, DASH, plant-based, low energy density, and low glycemic load, with high nutrient/phytonutrient density, would increase public motivation and authoritative support for early/timely prevention, optimally merging with other dietary/health goals, for lifelong BC prevention.

Monoallelic characteristic-bearing heterozygous L1053X in BRCA2 gene among Sudanese women with breast cancer

Background

Breast cancer (BC) is the most common type of cancer in women. Among many risk factors of BC, mutations in BRCA2 gene were found to be the primary cause in 5–10% of cases. The majority of deleterious mutations are frameshift or nonsense mutations. Most of the reported BRCA2 mutations are protein truncating mutations.

Methods

The study aimed to describe the pattern of mutations including single nucleotide polymorphisms (SNPs) and variants of the BRCA2 (exon11) gene among Sudanese women patients diagnosed with BC. In this study a specific region of BRCA2 exon 11 was targeted using PCR and DNA sequencing.

Results

Early onset cases 25/45 (55.6%) were premenopausal women with a mean age of 36.6 years. Multiparity was more frequent within the study amounting to 30 cases (66.6%), with a mean parity of 4.1. Ductal type tumor was the predominant type detected in 22 cases (48.8%) among the reported histotypes. A heterozygous monoallelic nonsense mutation at nucleotide 3385 was found in four patients out of 9, where TTA codon was converted into the stop codon TGA.

Conclusion

This study detected a monoallelic nonsense mutation in four Sudanese female patients diagnosed with early onset BC from different families. Further work is needed to demonstrate its usefulness in screening of BC.

Estrogen receptors in breast and bone: from virtue of remodeling to vileness of metastasis

Bone metastasis is a prominent cause of morbidity and mortality in cancer. High rates of bone colonization in breast cancer, especially in the subtype expressing estrogen receptors (ERs), suggest tissue-specific proclivities for metastatic tumor formation. The mechanisms behind this subtype-specific organ-tropism remains largely elusive. Interestingly, as the major driver of ER+ breast cancer, ERs also have important roles in bone development and homeostasis. Thus, any agents targeting ER will also inevitably affect the microenvironment, which involves the osteoblasts and osteoclasts. Yet, how such microenvironmental effects are integrated with direct therapeutic responses of cancer cells remain poorly understood. Recent findings on ER mutations, especially their enrichment in bone metastasis, raised even more provocative questions on the role of ER in cancer-bone interaction. In this review, we evaluate the importance of ERs in bone metastasis and discuss new avenues of investigation for bone metastasis treatment based on current knowledge.

Müllerian intra-abdominal carcinomatosis in hereditary breast ovarian cancer syndrome: implications for risk-reducing surgery

More than 40 years ago Lynch et al. described several multigenerational breast cancer family pedigrees which demonstrated autosomal dominant inheritance of a trait(s) that increased risks for both breast and ovarian cancers. Mutation carriers in at least 90 % of these hereditary breast ovarian cancer (HBOC) syndrome families have been linked to cancer-associated mutations in the genes BRCA1 and BRCA2. This review focuses on the contributions of Lynch, colleagues and collaborators and pertinent literature, toward defining the HBOC syndrome, the cancer risks that the inherited adverse mutations convey, the gynecologic tissues and organs from which the malignancy may arise to disseminate throughout the pelvic and abdominal organs and peritoneum and how this information can be used to reduce the risk and morbidities of intra-abdominal carcinomatosis in effected individuals.

Influence of vitamin D signaling on hormone receptor status and HER2 expression in breast cancer

PURPOSE

Breast cancer is a significant global public health issue. It is the leading cause of death among women around the world, with an incidence increasing annually. In recent years, there has been more and more information in the literature regarding a protective role of vitamin D in cancer. Increasingly preclinical and clinical studies suggest that vitamin D optimal levels can reduce the risk of breast cancer development and regulate cancer-related pathways.

METHOD

In this review, we focus on the importance of vitamin D in breast cancers, discussing especially the influence of vitamin D signaling on estrogen receptor and human epidermal growth factor receptor 2 (HER2), two major biomarkers of breast cancer today.

CONCLUSION

We discuss the possibility of actual and future targeted therapeutic approaches for vitamin D signaling in breast cancer.

Hormonal contraception and breast cancer, what more do we need to know?

Most women use hormonal contraception for more than 30 years and for many, this may involve exposure in their older reproductive years when baseline breast cancer risk rises steeply. Overall, the risk of breast cancer diagnosis with exposure to hormonal contraception is very small and outweighed by its contraceptive benefits but despite this, there are still outstanding questions for all methods used in clinical practice due to paucity of available evidence, lack of which should not be taken to imply safety. This is exemplified by the following assumptions: the progestogen-only pill and long-acting reversible contraceptives are 'breast-safe' options in peri-menopausal women, use of the levonorgestrel intrauterine system for the management of endometrial pathology in breast cancer survivors is less likely to promote disease recurrence and the benefit all hormonal contraceptive methods confer in reducing unplanned pregnancy in women at high familial risk outweigh the risk of breast cancer diagnosis. There is no data on risk with the concurrent prescription of hormone replacement therapy in women exhibiting climacteric symptoms who are still menstruating. Advice of GPs and Community Sexual & Reproductive Health specialists will inevitably be sought about some or all these issues and in the absence of conclusive evidence from clinical studies, caution should be applied and women counselled appropriately.

The management of sexuality, intimacy, and menopause symptoms (SIMS) after prophylactic bilateral salpingo-oophorectomy: How to maintain sexual health in "previvors"

"Previvors", or "pre-survivors", are individuals who do not have cancer but have a genetic predisposition to cancer. One such example is women with BRCA mutations. As a result of their predisposition to cancer, many will undergo a bilateral salpingo-oophorectomy when they are premenopausal. For premenopausal women, the removal of ovaries results in the depletion of estrogen, immediate menopause, and, in many cases, resultant Sexuality, Intimacy, and Menopausal Symptoms (SIMS). Furthermore, they may undergo changes in body image. SIMS are underreported by patients and underdiagnosed by practitioners. At the time of diagnosis or at preoperative visits, women should be informed of the potential physiologic, hormonal, and psychosocial effects of their risk-reducing surgery. There are many modalities for management of these symptoms. Successful treatment requires the provider's awareness of the problem, ability to identify it, and willingness to treat it.

Loss of BRCA1 in the Cells of Origin of Ovarian Cancer Induces Glycolysis: A Window of Opportunity for Ovarian Cancer Chemoprevention

Mutations in the breast cancer susceptibility gene 1 (BRCA1) are associated with an increased risk of developing epithelial ovarian cancer. However, beyond the role of BRCA1 in DNA repair, little is known about other mechanisms by which BRCA1 impairment promotes carcinogenesis. Given that altered metabolism is now recognized as important in the initiation and progression of cancer, we asked whether the loss of BRCA1 changes metabolism in the cells of origin of ovarian cancer. The findings show that silencing BRCA1 in ovarian surface epithelial and fallopian tube cells increased glycolysis. Furthermore, when these cells were transfected with plasmids carrying deleterious BRCA1 mutations (5382insC or the P1749R), there was an increase in hexokinase-2 (HK2), a key glycolytic enzyme. This effect was mediated by MYC and the STAT3. To target the metabolic phenotype induced by loss of BRCA1, a drug-repurposing approach was used and aspirin was identified as an agent that counteracted the increase in HK2 and the increase in glycolysis induced by BRCA1 impairment. Evidence from this study indicates that the tumor suppressor functions of BRCA1 extend beyond DNA repair to include metabolic endpoints and identifies aspirin as an ovarian cancer chemopreventive agent capable of reversing the metabolic derangements caused by loss of BRCA1. Cancer Prev Res; 10(4); 255-66. ©2017 AACR.

Prognostic significance of BRCA mutations in ovarian cancer: an updated systematic review with meta-analysis

There is no consensus on the syntheses concerning the impact of BRCA mutation on ovarian cancer survival. A systematic review and meta-analysis of observational studies was conducted that evaluated the impact of BRCA mutations on the survival outcomes of patients with ovarian cancer. The primary outcome measure was overall survival (OS) and secondary outcome was progression-free survival (PFS). We presented data with hazard ratios (HRs) and 95% confidence interval (CI) and pooled them using the random-effects models. From 2,624 unique records, 34 eligible studies including 18,396 patients were identified. BRCA1/2 mutations demonstrated both OS and PFS benefits in patients with ovarian cancer (OS: HR = 0.67, 95% CI, 0.57 to 0.78, I2 = 76.5%, P <0.001; PFS: HR = 0.62, 95% CI, 0.53 to 0.73, I2 = 18.1%, P = 0.261). For BRCA1 mutation carriers, the HRs for OS and PFS benefits were 0.73 (95% CI, 0.63 to 0.86) and 0.68 (95% CI, 0.52 to 0.89), respectively. For BRCA2 mutation carriers, the HRs for OS and PFS benefits were 0.57 (95% CI, 0.45 to 0.73) and 0.48 (95% CI, 0.30 to 0.75), respectively. The results of subgroup analyses for OS stratified by study quality, tumor stage, study design, sample size, number of research center, duration of follow-up, baseline characteristics adjusted and tumor histology were mostly constant across BRCA1/2, BRCA1 and BRCA2 mutation subtypes. In summary, for patients with ovarian cancer, BRCA mutations were associated with improved OS and PFS. Further large-scale prospective cohort studies should be conducted to test its benefits in specific patients.

Prognostic significance of BRCA mutations in ovarian cancer: an updated systematic review with meta-analysis

There is no consensus on the syntheses concerning the impact of BRCA mutation on ovarian cancer survival. A systematic review and meta-analysis of observational studies was conducted that evaluated the impact of BRCA mutations on the survival outcomes of patients with ovarian cancer. The primary outcome measure was overall survival (OS) and secondary outcome was progression-free survival (PFS). We presented data with hazard ratios (HRs) and 95% confidence interval (CI) and pooled them using the random-effects models. From 2,624 unique records, 34 eligible studies including 18,396 patients were identified. BRCA1/2 mutations demonstrated both OS and PFS benefits in patients with ovarian cancer (OS: HR = 0.67, 95% CI, 0.57 to 0.78, I2 = 76.5%, P <0.001; PFS: HR = 0.62, 95% CI, 0.53 to 0.73, I2 = 18.1%, P = 0.261). For BRCA1 mutation carriers, the HRs for OS and PFS benefits were 0.73 (95% CI, 0.63 to 0.86) and 0.68 (95% CI, 0.52 to 0.89), respectively. For BRCA2 mutation carriers, the HRs for OS and PFS benefits were 0.57 (95% CI, 0.45 to 0.73) and 0.48 (95% CI, 0.30 to 0.75), respectively. The results of subgroup analyses for OS stratified by study quality, tumor stage, study design, sample size, number of research center, duration of follow-up, baseline characteristics adjusted and tumor histology were mostly constant across BRCA1/2, BRCA1 and BRCA2 mutation subtypes. In summary, for patients with ovarian cancer, BRCA mutations were associated with improved OS and PFS. Further large-scale prospective cohort studies should be conducted to test its benefits in specific patients.

Association of breast cancer risk in BRCA1 and BRCA2 mutation carriers with genetic variants showing differential allelic expression: identification of a modifier of breast cancer risk at locus 11q22.3

PURPOSE

Cis-acting regulatory SNPs resulting in differential allelic expression (DAE) may, in part, explain the underlying phenotypic variation associated with many complex diseases. To investigate whether common variants associated with DAE were involved in breast cancer susceptibility among BRCA1 and BRCA2 mutation carriers, a list of 175 genes was developed based of their involvement in cancer-related pathways.

METHODS

Using data from a genome-wide map of SNPs associated with allelic expression, we assessed the association of ~320 SNPs located in the vicinity of these genes with breast and ovarian cancer risks in 15,252 BRCA1 and 8211 BRCA2 mutation carriers ascertained from 54 studies participating in the Consortium of Investigators of Modifiers of BRCA1/2.

RESULTS

We identified a region on 11q22.3 that is significantly associated with breast cancer risk in BRCA1 mutation carriers (most significant SNP rs228595 p = 7 × 10-6). This association was absent in BRCA2 carriers (p = 0.57). The 11q22.3 region notably encompasses genes such as ACAT1, NPAT, and ATM. Expression quantitative trait loci associations were observed in both normal breast and tumors across this region, namely for ACAT1, ATM, and other genes. In silico analysis revealed some overlap between top risk-associated SNPs and relevant biological features in mammary cell data, which suggests potential functional significance.

CONCLUSION

We identified 11q22.3 as a new modifier locus in BRCA1 carriers. Replication in larger studies using estrogen receptor (ER)-negative or triple-negative (i.e., ER-, progesterone receptor-, and HER2-negative) cases could therefore be helpful to confirm the association of this locus with breast cancer risk.

Population Attributable Risk of Modifiable and Nonmodifiable Breast Cancer Risk Factors in Postmenopausal Breast Cancer

We examined the proportions of multiple types of breast cancers in the population that were attributable to established risk factors, focusing on behaviors that are modifiable at menopause. We estimated the full and partial population attributable risk percentages (PAR%) by combining the relative risks and the observed prevalence rates of the risk factors of interest. A total of 8,421 cases of invasive breast cancer developed in postmenopausal women (n = 121,700) in the Nurses' Health Study from 1980-2010. We included the following modifiable risk factors in our analyses: weight change since age 18 years, alcohol consumption, physical activity level, breastfeeding, and menopausal hormone therapy use. Additionally, the following nonmodifiable factors were included: age, age at menarche, height, a combination of parity and age at first birth, body mass index at age 18 years, family history of breast cancer, and prior benign breast disease. When we considered all risk factors (and controlled for age), the PAR% for invasive breast cancers was 70.0% (95% confidence interval: 55.0, 80.7). When considering only modifiable factors, we found that changing the risk factor profile to the lowest weight gain, no alcohol consumption, high physical activity level, breastfeeding, and no menopausal hormone therapy use was associated with a PAR% of 34.6% (95% confidence interval: 22.7, 45.4). The PAR% for modifiable factors was higher for estrogen receptor-positive breast cancers (PAR% = 39.7%) than for estrogen receptor-negative breast cancers (PAR% = 27.9%). Risk factors that are modifiable at menopause account for more than one-third of postmenopausal breast cancers; therefore, a substantial proportion of breast cancer in the United States is preventable.

Lifestyle Risk Factors for Breast Cancer in BRCA1/2-Mutation Carriers Around Childbearing Age

BRCA1/2-mutation carriers are at high risk of breast cancer (BC) and ovarian cancer. Physical inactivity, overweight (body mass index ≥25, BMI), smoking, and alcohol consumption are jointly responsible for about 1 in 4 postmenopausal BC cases in the general population. Limited evidence suggests physical activity also increases BC risk in BRCA1/2-mutation carriers. Women who have children often reduce physical activity and have weight gain, which increases BC risk. We assessed aforementioned lifestyle factors in a cohort of 268 BRCA1/2-mutation carriers around childbearing age (born between 1968 and 1983, median age 33 years, range 21–44). Furthermore, we evaluated the effect of having children on physical inactivity and overweight. Carriers were asked about lifestyle 4–6 weeks after genetic diagnosis at the Familial Cancer Clinic Nijmegen. Physical inactivity was defined as sports activity fewer than once a week. Carriers were categorized according to the age of their youngest child (no children, age 0–3 years and ≥4 years). In total, 48% of carriers were physically inactive, 41% were overweight, 27% smoked, and 70% consumed alcohol (3% ≥8 beverages/week). Physical inactivity was 4–5 times more likely in carriers with children. Overweight was not associated with having children. Carriers with children are a subgroup that may specifically benefit from lifestyle support to reduce BC risk.

rs15869 at miRNA binding site in BRCA2 is associated with breast cancer susceptibility

BRCA1 and BRCA2 mutations confer an increased lifetime risk of breast cancer; however, the associations of microRNA (miRNA) binding site single nucleotide polymorphisms (SNPs) in 3' untranslated region (3'-UTR) of BRCA1 and BRCA2 with breast cancer (BC) risk were rarely reported. In this case-control study (498 BC patients and 498 matched controls), three SNPs (rs8176318, rs12516 and rs15869) were selected in the 3'-UTR of BRCA1 and BRCA2 genes, which were within miRNA-binding seed regions and might have potential function to regulate the expression of BRCA1/BRCA2. Unconditional logistic regression model was used to analyze the association between three SNPs and BC risk with adjustment of reproductive factors, and Student's t test was performed to assess relative expression of BRCA2 in human breast cancer cell lines. Multifactor dimensionality reduction method was applied to calculate gene-reproductive factors interactions. A novel finding showed that AC [odds ratio (OR) 1.524; 95% confidence interval (CI) 1.141-2.035] genotype of rs15869 in BRCA2 could increase the risk of BC and recombinant plasmid-pGenesil-1-miR-627 could negatively regulate the expression of BRCA2 in MCF-7 and MDA-MB-231 cells. Gene-reproductive factors interactions analysis revealed that rs15869 together with age at menarche and number of pregnancy could increase the risk of BC by 2.39-fold and TT genotype (OR 0.316; 95% CI 0.130-0.767) of rs8176318 had a significant association with progesterone receptor status in BC patients. Our findings suggest that the miRNA-binding SNPs in BRCA1/BRCA2 and their interaction with reproductive factors might contribute to BC risk, and miR-627 might down-regulate BRCA2 expression in MCF-7 and MDA-MB-231 cells.

Integrating precision cancer medicine into healthcare-policy, practice, and research challenges

Precision medicine (PM) can be defined as a predictive, preventive, personalized, and participatory healthcare service delivery model. Recent developments in molecular biology and information technology make PM a reality today through the use of massive amounts of genetic, ‘omics’, clinical, environmental, and lifestyle data. With cancer being one of the most prominent public health threats in developed countries, both the research community and governments have been investing significant time, money, and efforts in precision cancer medicine (PCM). Although PCM research is extremely promising, a number of hurdles still remain on the road to an optimal integration of standardized and evidence-based use of PCM in healthcare systems. Indeed, PCM raises a number of technical, organizational, ethical, legal, social, and economic challenges that have to be taken into account in the development of an appropriate health policy framework. Here, we highlight some of the more salient issues regarding the standards needed for integration of PCM into healthcare systems, and we identify fields where more research is needed before policy can be implemented. Key challenges include, but are not limited to, the creation of new standards for the collection, analysis, and sharing of samples and data from cancer patients, and the creation of new clinical trial designs with renewed endpoints. We believe that these issues need to be addressed as a matter of priority by public health policymakers in the coming years for a better integration of PCM into healthcare.

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.

Epidemiology of Patients with Ovarian Cancer with and Without a BRCA1/2 Mutation

Ovarian cancer survival rates have improved only slightly in recent decades; however, treatment of this disease is expected to undergo rapid change as strategies incorporating molecular-targeted therapies enter clinical practice. Carriers of deleterious mutations (defined as a harmful mutation) in either the BRCA1 or BRCA2 gene (BRCAm) have a significantly increased risk of developing ovarian cancer. Epidemiology data in large (>500 patients) unselected ovarian cancer populations suggest that the expected incidence rate for BRCAm in this population is 12-14 %. Patients with a BRCAm are typically diagnosed at a younger age than those without a BRCAm. Associations with BRCAm vary according to ethnicity, with women of Ashkenazi Jewish descent being 10 times more likely to have a BRCAm than the general population. In terms of survival, patients with invasive epithelial ovarian cancer who have a BRCAm may have improved overall survival compared with patients who do not carry a BRCAm. Although genetic testing for BRCAm remains relatively uncommon in ovarian cancer patients, testing is becoming cheaper and increasingly accessible; however, this approach is not without numerous social, ethical and policy issues. Current guidelines recommend BRCAm testing in specific ovarian cancer patients only; however, with the emergence of treatments that are targeted at patients with a BRCAm, genetic testing of all patients with high-grade serous ovarian cancer may lead to improved patient outcomes in this patient population. Knowledge of BRCAm status could, therefore, help to inform treatment decisions and identify relatives at increased risk of developing cancer.

Ovarian cancer

Ovarian cancer is not a single disease and can be subdivided into at least five different histological subtypes that have different identifiable risk factors, cells of origin, molecular compositions, clinical features and treatments. Ovarian cancer is a global problem, is typically diagnosed at a late stage and has no effective screening strategy. Standard treatments for newly diagnosed cancer consist of cytoreductive surgery and platinum-based chemotherapy. In recurrent cancer, chemotherapy, anti-angiogenic agents and poly(ADP-ribose) polymerase inhibitors are used, and immunological therapies are currently being tested. High-grade serous carcinoma (HGSC) is the most commonly diagnosed form of ovarian cancer and at diagnosis is typically very responsive to platinum-based chemotherapy. However, in addition to the other histologies, HGSCs frequently relapse and become increasingly resistant to chemotherapy. Consequently, understanding the mechanisms underlying platinum resistance and finding ways to overcome them are active areas of study in ovarian cancer. Substantial progress has been made in identifying genes that are associated with a high risk of ovarian cancer (such as BRCA1 and BRCA2), as well as a precursor lesion of HGSC called serous tubal intraepithelial carcinoma, which holds promise for identifying individuals at high risk of developing the disease and for developing prevention strategies.

Ovarian cancer

Ovarian cancer is not a single disease and can be subdivided into at least five different histological subtypes that have different identifiable risk factors, cells of origin, molecular compositions, clinical features and treatments. Ovarian cancer is a global problem, is typically diagnosed at a late stage and has no effective screening strategy. Standard treatments for newly diagnosed cancer consist of cytoreductive surgery and platinum-based chemotherapy. In recurrent cancer, chemotherapy, anti-angiogenic agents and poly(ADP-ribose) polymerase inhibitors are used, and immunological therapies are currently being tested. High-grade serous carcinoma (HGSC) is the most commonly diagnosed form of ovarian cancer and at diagnosis is typically very responsive to platinum-based chemotherapy. However, in addition to the other histologies, HGSCs frequently relapse and become increasingly resistant to chemotherapy. Consequently, understanding the mechanisms underlying platinum resistance and finding ways to overcome them are active areas of study in ovarian cancer. Substantial progress has been made in identifying genes that are associated with a high risk of ovarian cancer (such as BRCA1 and BRCA2), as well as a precursor lesion of HGSC called serous tubal intraepithelial carcinoma, which holds promise for identifying individuals at high risk of developing the disease and for developing prevention strategies.

Ovarian cancer

Ovarian cancer is not a single disease and can be subdivided into at least five different histological subtypes that have different identifiable risk factors, cells of origin, molecular compositions, clinical features and treatments. Ovarian cancer is a global problem, is typically diagnosed at a late stage and has no effective screening strategy. Standard treatments for newly diagnosed cancer consist of cytoreductive surgery and platinum-based chemotherapy. In recurrent cancer, chemotherapy, anti-angiogenic agents and poly(ADP-ribose) polymerase inhibitors are used, and immunological therapies are currently being tested. High-grade serous carcinoma (HGSC) is the most commonly diagnosed form of ovarian cancer and at diagnosis is typically very responsive to platinum-based chemotherapy. However, in addition to the other histologies, HGSCs frequently relapse and become increasingly resistant to chemotherapy. Consequently, understanding the mechanisms underlying platinum resistance and finding ways to overcome them are active areas of study in ovarian cancer. Substantial progress has been made in identifying genes that are associated with a high risk of ovarian cancer (such as BRCA1 and BRCA2), as well as a precursor lesion of HGSC called serous tubal intraepithelial carcinoma, which holds promise for identifying individuals at high risk of developing the disease and for developing prevention strategies.

Differential Potential of Pharmacological PARP Inhibitors for Inhibiting Cell Proliferation and Inducing Apoptosis in Human Breast Cancer Cells

BRCA1/2-mutant cells are hypersensitive to inactivation of poly(ADP-ribose) polymerase 1 (PARP-1). We recently showed that inhibition of PARP-1 by NU1025 is strongly cytotoxic for BRCA1-positive BT-20 cells, but not BRCA1-deficient SKBr-3 cells. These results raised the possibility that other PARP-1 inhibitors, particularly those tested in clinical trials, may be more efficacious against BRCA1-deficient SKBr-3 breast cancer cells than NU1025. Thus, in the presented study the cytotoxicity of four PARP inhibitors under clinical evaluation (olaparib, rucaparib, iniparib and AZD2461) was examined and compared to that of NU1025. The sensitivity of breast cancer cells to the PARP-1 inhibition strongly varied. Remarkably, BRCA-1-deficient SKBr-3 cells were almost completely insensitive to NU1025, olaparib and rucaparib, whereas BRCA1-expressing BT-20 cells were strongly affected by NU1025 even at low doses. In contrast, iniparib and AZD2461 were cytotoxic for both BT-20 and SKBr-3 cells. Of the four tested PARP-1 inhibitors only AZD2461 strongly affected cell cycle progression. Interestingly, the anti-proliferative and pro-apoptotic potential of the tested PARP-1 inhibitors clearly correlated with their capacity to damage DNA. Further analyses revealed that proteomic signatures of the two studied breast cancer cell lines strongly differ, and a set of 197 proteins was differentially expressed in NU1025-treated BT-20 cancer cells. These results indicate that BT-20 cells may harbor an unknown defect in DNA repair pathway(s) rendering them sensitive to PARP-1 inhibition. They also imply that therapeutic applicability of PARP-1 inhibitors is not limited to BRCA mutation carriers but can be extended to patients harboring deficiencies in other components of the pathway(s).

Women at high risk of breast cancer: Molecular characteristics, clinical presentation and management

The presence of breast cancer in any first-degree female relative in general nearly doubles the risk for a proband and the risk gradually increases with the number of affected relatives. Current advances in molecular oncology and oncogenetics may enable the identification of high-risk individuals with breast-cancer predisposition. The best-known forms of hereditary breast cancer (HBC) are caused by mutations in the high-penetrance genes BRCA1 and BRCA2. Other genes, including PTEN, TP53, STK11/LKB1, CDH1, PALB2, CHEK2, ATM, MRE11, RAD50, NBS1, BRIP1, FANCA, FANCC, FANCM, RAD51, RAD51B, RAD51C, RAD51D, and XRCC2 have been described as high- or moderate-penetrance breast cancer-susceptibility genes. The majority of breast cancer-susceptibility genes code for tumor suppressor proteins that are involved in critical processes of DNA repair pathways. This is of particular importance for those women who, due to their increased risk of breast cancer, may be subjected to more frequent screening but due to their repair deficiency might be at the risk of developing radiation-induced malignancies. It has been proven that cancers arising from the most frequent BRCA1 gene mutation carriers differ significantly from the sporadic disease of age-matched controls in their histopathological appearances and molecular characteristics. The increased depth of mutation detection brought by next-generation sequencing and a better understanding of the mechanisms through which these mutations cause the disease will bring novel insights in terms of oncological prevention, diagnostics, and therapeutic options for HBC patients.

Can diet and lifestyle prevent breast cancer: what is the evidence?

Breast cancer is the most common cancer among women in both developed and less-developed countries. Rates of breast cancer are increasing worldwide, with a particular increase in postmenopausal and estrogen receptor-positive cases. The World Cancer Research Fund (WCRF) and American Cancer Society (ACS) cancer prevention guidelines recommend maintaining a healthy weight, undertaking at least 150 minutes of moderate intensity exercise per week, limiting alcohol consumption, and eating a plant-based diet. Observational data link adherence to physical activity and alcohol guidelines throughout life to a reduced risk of developing pre- and postmenopausal breast cancer. Weight control throughout life appears to prevent cases after menopause. Adherence to a healthy dietary pattern does not have specific effects on breast cancer risk but remains important as it reduces the risk for other common diseases, such as cardiovascular disease (CVD), diabetes, and dementia. Emerging data suggest that smoking during adolescence or early adulthood increases later risk of breast cancer. Lifestyle factors appear to modify risk among high-risk women with a family history and those with typical risk of the general population, although their effects among carriers of BRCA mutations are not well defined. Recent expert reports estimate that successful lifestyle changes could prevent 25% to 30% of cases of breast cancer. These reductions will only be achieved if we can implement targeted prevention programs for high-risk women and women in population-based breast screening programs during childhood, adolescence, and early adulthood when the rapidly developing breast is particularly susceptible to carcinogenesis.

[Infertility and breast cancer: Is there a link? Updated review of the literature and meta-analysis]

The objective of this review was to assess the level of risk of breast cancer of patients consulting for infertility.

METHODS

Studies of cohorts and case-control were extracted from the Pubmed database from January 2000 until May 2015 through the following keywords: "infertility"; "endometriosis"; "polycystic ovary syndrome"; "breast cancer", "cancer risk". Eleven publications were finally selected after exclusion of publications dealing with infertility after breast cancer. Our meta-analysis, involving 10 of these publications, was performed using Review Manager software, Cochrane Collaboration, 2014. The results were calculated by etiology of infertility, polycystic ovary syndrome (PCOS) and endometriosis, as well as globally.

RESULTS

The analysis of these published epidemiological studies confirms that infertility is not a breast cancer risk factor, but the results are contradictory. Three studies have shown a significantly increased risk of breast cancer in a population of infertile women, while 7 others have not found this risk. These contradictions are due to the heterogeneity of the studies, the included populations, the follow-up periods and confounding factors. Our meta-analysis of the selected studies has not identified a significant association between infertility and breast cancer risk (1.05; 95% CI [0.96-1.16]). A subgroup analysis on endometriosis and PCOS showed no significant association either, with an OR of 1.02 (95% CI [0.87-1.19]) and 1.19 (95% CI [0.93-1.51]), respectively.

CONCLUSION

Infertility is not an identified risk factor for breast cancer. A message reassuring about a possible risk of infertility-related breast cancer should be given to these patients. Infertility is therefore not an indication of increased breast surveillance.

Gene-environment interaction and risk of breast cancer

Hereditary, genetic factors as well as lifestyle and environmental factors, for example, parity and body mass index, predict breast cancer development. Gene-environment interaction studies may help to identify subgroups of women at high-risk of breast cancer and can be leveraged to discover new genetic risk factors. A few interesting results in studies including over 30,000 breast cancer cases and healthy controls indicate that such interactions exist. Explorative gene-environment interaction studies aiming to identify new genetic or environmental factors are scarce and still underpowered. Gene-environment interactions might be stronger for rare genetic variants, but data are lacking. Ongoing initiatives to genotype larger sample sets in combination with comprehensive epidemiologic databases will provide further opportunities to study gene-environment interactions in breast cancer. However, based on the available evidence, we conclude that associations between the common genetic variants known today and breast cancer risk are only weakly modified by environmental factors, if at all.

Refining Breast Cancer Risk Stratification: Additional Genes, Additional Information

Recent advances in genomic technology have enabled far more rapid, less expensive sequencing of multiple genes than was possible only a few years ago. Advances in bioinformatics also facilitate the interpretation of large amounts of genomic data. New strategies for cancer genetic risk assessment include multiplex sequencing panels of 5 to more than 100 genes (in which rare mutations are often associated with at least two times the average risk of developing breast cancer) and panels of common single-nucleotide polymorphisms (SNPs), combinations of which are generally associated with more modest cancer risks (more than twofold). Although these new multiple-gene panel tests are used in oncology practice, questions remain about the clinical validity and the clinical utility of their results. To translate this increasingly complex genetic information for clinical use, cancer risk prediction tools are under development that consider the joint effects of all susceptibility genes, together with other established breast cancer risk factors. Risk-adapted screening and prevention protocols are underway, with ongoing refinement as genetic knowledge grows. Priority areas for future research include the clinical validity and clinical utility of emerging genetic tests; the accuracy of developing cancer risk prediction models; and the long-term outcomes of risk-adapted screening and prevention protocols, in terms of patients' experiences and survival.

Mutation Screening of 1,237 Cancer Genes across Six Model Cell Lines of Basal-Like Breast Cancer

Basal-like breast cancer is an aggressive subtype generally characterized as poor prognosis and lacking the expression of the three most important clinical biomarkers, estrogen receptor, progesterone receptor, and HER2. Cell lines serve as useful model systems to study cancer biology in vitro and in vivo. We performed mutational profiling of six basal-like breast cancer cell lines (HCC38, HCC1143, HCC1187, HCC1395, HCC1954, and HCC1937) and their matched normal lymphocyte DNA using targeted capture and next-generation sequencing of 1,237 cancer-associated genes, including all exons, UTRs and upstream flanking regions. In total, 658 somatic variants were identified, of which 378 were non-silent (average 63 per cell line, range 37–146) and 315 were novel (not present in the Catalogue of Somatic Mutations in Cancer database; COSMIC). 125 novel mutations were confirmed by Sanger sequencing (59 exonic, 48 3’UTR and 10 5’UTR, 1 splicing), with a validation rate of 94% of high confidence variants. Of 36 mutations previously reported for these cell lines but not detected in our exome data, 36% could not be detected by Sanger sequencing. The base replacements C/G>A/T, C/G>G/C, C/G>T/A and A/T>G/C were significantly more frequent in the coding regions compared to the non-coding regions (OR 3.2, 95% CI 2.0–5.3, P<0.0001; OR 4.3, 95% CI 2.9–6.6, P<0.0001; OR 2.4, 95% CI 1.8–3.1, P<0.0001; OR 1.8, 95% CI 1.2–2.7, P = 0.024, respectively). The single nucleotide variants within the context of T[C]T/A[G]A and T[C]A/T[G]A were more frequent in the coding than in the non-coding regions (OR 3.7, 95% CI 2.2–6.1, P<0.0001; OR 3.8, 95% CI 2.0–7.2, P = 0.001, respectively). Copy number estimations were derived from the targeted regions and correlated well to Affymetrix SNP array copy number data (Pearson correlation 0.82 to 0.96 for all compared cell lines; P<0.0001). These mutation calls across 1,237 cancer-associated genes and identification of novel variants will aid in the design and interpretation of biological experiments using these six basal-like breast cancer cell lines.

Inverse birth cohort effects in ovarian cancer: Increasing risk in BRCA1/2 mutation carriers and decreasing risk in the general population

OBJECTIVE

BRCA1/2 carriers are at increased risk of ovarian cancer, and some reports suggest an increasing risk in more recent birth cohorts. In contrast, decreasing incidences have been observed in the general population. The aim was to assess the birth cohort effect on ovarian cancer risk in BRCA1/2 carriers relative to their background general population.

METHODS

Data on ovarian cancer incidence was collected for a cohort of 1050 BRCA1/2 mutation carriers ascertained by our regional clinic and retrieved from the general Dutch population cancer registry. Birth cohorts were categorized as pre-1935, 1935-1953, post-1953. Birth cohort effects on the ovarian cancer risk were estimated using hazard ratios (HRs) in BRCA1/2 carriers and Poisson rate ratios in the general population. Standardized incidence ratios (SIRs) were calculated to compare populations. HRs were adjusted for mutation position and family history.

RESULTS

Compared to the pre-1935 cohort, BRCA1 carriers in the 1935-1953 and post-1953 cohorts had an increased ovarian cancer risk of HRadjusted 1.54 (95% CI 1.11-2.14) and 2.40 (95% CI 1.56-3.69), respectively. BRCA2 carriers in the 1935-1953 cohort had an HRadjusted of 3.01 (95% CI 1.47-6.13). The SIRs for the 1935-1953 and post-1953 cohorts were 1.7 and 2.7, respectively, for the BRCA1 carriers and 1.6 times and 2.4 times, respectively, for BRCA2 carriers.

CONCLUSIONS

Mutation carriers, particularly BRCA1 carriers, born in the most recent cohorts, have the highest additional ovarian cancer risk as compared to the general population.

Defects in the Fanconi Anemia Pathway in Head and Neck Cancer Cells Stimulate Tumor Cell Invasion through DNA-PK and Rac1 Signaling

PURPOSE

Head and neck squamous cell carcinoma (HNSCC) remains a devastating disease, and Fanconi anemia (FA) gene mutations and transcriptional repression are common. Invasive tumor behavior is associated with poor outcome, but relevant pathways triggering invasion are poorly understood. There is a significant need to improve our understanding of genetic pathways and molecular mechanisms driving advanced tumor phenotypes, to develop tailored therapies. Here we sought to investigate the phenotypic and molecular consequences of FA pathway loss in HNSCC cells.

EXPERIMENTAL DESIGN

Using sporadic HNSCC cell lines with and without FA gene knockdown, we sought to characterize the phenotypic and molecular consequences of FA deficiency. FA pathway inactivation was confirmed by the detection of classic hallmarks of FA following exposure to DNA cross-linkers. Cells were subjected to RNA sequencing with qRT-PCR validation, followed by cellular adhesion and invasion assays in the presence and absence of DNA-dependent protein kinase (DNA-PK) and Rac1 inhibitors.

RESULTS

We demonstrate that FA loss in HNSCC cells leads to cytoskeletal reorganization and invasive tumor cell behavior in the absence of proliferative gains. We further demonstrate that cellular invasion following FA loss is mediated, at least in part, through NHEJ-associated DNA-PK and downstream Rac1 GTPase activity.

CONCLUSIONS

These findings demonstrate that FA loss stimulates HNSCC cell motility and invasion, and implicate a targetable DNA-PK/Rac1 signaling axis in advanced tumor phenotypes.

Breastfeeding and breast cancer risk by receptor status--a systematic review and meta-analysis

BACKGROUND

Breastfeeding is inversely associated with overall risk of breast cancer. This association may differ in breast cancer subtypes defined by receptor status, as they may reflect different mechanisms of carcinogenesis. We conducted a systematic review and meta-analysis of case-control and prospective cohort studies to investigate the association between breastfeeding and breast cancer by estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) status.

DESIGN

We searched the PubMed and Scopus databases and bibliographies of pertinent articles to identify relevant articles and used random-effects models to calculate summary odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

This meta-analysis represents 27 distinct studies (8 cohort and 19 case-control), with a total of 36 881 breast cancer cases. Among parous women, the risk estimates for the association between ever (versus never) breastfeeding and the breast cancers negative for both ER and PR were similar in three cohort and three case-control studies when results were adjusted for several factors, including the number of full-term pregnancies (combined OR 0.90; 95% CI 0.82-0.99), with little heterogeneity and no indication of publication bias. In a subset of three adjusted studies that included ER, PR, and HER2 status, ever breastfeeding showed a stronger inverse association with triple-negative breast cancer (OR 0.78; 95% CI 0.66-0.91) among parous women. Overall, cohort studies showed no significant association between breastfeeding and ER+/PR+ or ER+ and/or PR+ breast cancers, although one and two studies (out of four and seven studies, respectively) showed an inverse association.

CONCLUSIONS

This meta-analysis showed a protective effect of ever breastfeeding against hormone receptor-negative breast cancers, which are more common in younger women and generally have a poorer prognosis than other subtypes of breast cancer. The association between breastfeeding and receptor-positive breast cancers needs more investigation.

Prior oral contraceptive use in ovarian cancer patients: assessing associations with overall and progression-free survival

Background

Prior studies have described a reduced risk of developing ovarian cancer with the use of oral contraceptives. In this context, we decided to examine if oral contraceptive use prior to a diagnosis of ovarian cancer is associated with better overall and progression-free survival.

Methods

This retrospective cohort study included ovarian cancer patients who were seen at the Mayo Clinic in Rochester, Minnesota from 2000 through 2013. Patients completed a risk factor questionnaire about previous oral contraceptive use, and clinical data were extracted from the electronic medical record.

Results

A total of 1398 ovarian cancer patients responded to questions on oral contraceptive use; 571 reported no prior use with all others having responded affirmatively to oral contraceptive use. Univariate analyses found that oral contraceptive use (for example, ever versus never) was associated with better overall survival (hazard ratio (HR) 0.73 (95 % confidence interval (CI): 0.62, 0.86); p = 0.0002) and better progression-free survival (HR 0.71 (95 % CI: 0.61, 0.83); p < 0.0001). In multivariate analyses, contraceptive use continued to yield a favorable, statistically significant association with progression-free survival, but such was not the case with overall survival.

Conclusions

This study suggests that previous oral contraceptive use is associated with improved progression-free survival in patients diagnosed with ovarian cancer.

Living With Genetic Vulnerability: a Life Course Perspective

This is the second article of a two part series about utilizing the life course perspective (LCP) in genetic counseling. Secondary data analysis was conducted on a grounded theory, longitudinal study which provided a wide focus on living with hereditary breast and ovarian cancer (HBOC) risk. The aim of this analysis was to explore the longitudinal data for both the temporal and social context of living with BRCA mutation genetic test results. Sixteen women from two previous studies were interviewed on multiple occasions over an 8 year time period. The LCP was used to direct a thematic analysis of the data. Families experience the consequences of knowing they carry a BRCA1 or BRCA2 gene mutation long after the initial diagnosis. These women's experiences across time reflect the concepts of the LCP and show how life is changed when families know they live with a genetic vulnerability to an adult-onset and potentially life-threatening disease. Different emphases on concepts from the LCP were evident across the different age groups. For example, the group of 40-50 year old women emphasized the concept of linked lives, those in their 30's focused on human agency and women in their 20's were more focused on timing of events. This study helps give direction to healthcare providers counseling women living with a BRCA mutation.

Secondary Primary Malignancy Risk in Patients With Ovarian Cancer in Taiwan: A Nationwide Population-Based Study

To evaluate the incidence of secondary primary malignancy (SPM) in patients with ovarian cancer using a nationwide retrospective population-based dataset. Patients newly diagnosed with ovarian cancer between 1997 and 2010 were identified using Taiwan's National Health Insurance database. Patients with antecedent malignancies were excluded. Standardized incidence ratios (SIRs) for SPM were calculated and compared with the cancer incidence in the general population. Risk factors for cancer development were analyzed using Cox proportional hazard models. Effects of surgery, chemotherapy, and radiotherapy after ovarian cancer diagnosis were regarded as time-dependent variables to prevent immortal time bias. During the 14-year study period (follow-up of 56,214 person-years), 707 cancers developed in 12,127 patients with ovarian cancer. The SIR for all cancers was 2.78 (95% confidence interval 2.58-3.00). SIRs for follow-up periods of >5, 1-5, and <1 year were 1.87, 2.04, and 6.40, respectively. After the exclusion of SPM occurring within 1 year of ovarian cancer diagnosis, SIRs were significantly higher for cancers of the colon, rectum, and anus (2.14); lung and mediastinum (1.58); breast (1.68); cervix (1.65); uterus (7.96); bladder (3.17), and thyroid (2.23); as well as for leukemia (3.98) and others (3.83). Multivariate analysis showed that age ≥ 50 years was a significant SPM risk factor (hazard ratio [HR] 1.60). Different treatments for ovarian cancer, including radiotherapy (HR 2.07) and chemotherapy (HR 1.27), had different impacts on SPM risk. Patients with ovarian cancer are at increased risk of SPM development. Age ≥ 50 years, radiotherapy, and chemotherapy are independent risk factors. Close surveillance of patients at high risk should be considered for the early detection of SPM.

Clinical management of patients at inherited risk for gynecologic cancer

PURPOSE OF REVIEW

As more women with an inherited increased risk of gynecologic cancer are identified, the clinician will be challenged to counsel these women on risk-reducing strategies.

RECENT FINDINGS

Although there are some recent studies that show potential for ovarian cancer surveillance strategies, there remains no definitive evidence that surveillance leads to a stage shift or a reduction in mortality. Recent studies support the following conclusions: first, oral contraceptive use reduces ovarian cancer risk without significantly increasing breast cancer risk, second, salpingo-oophorectomy leads to a reduction in ovarian cancer, breast cancer, and overall mortality for women who are carriers of BRCA1 and BRCA2 mutations, and third, the 'ovarian cancers' associated with BRCA mutations actually include fallopian tube and peritoneal cancer and may have a precursor lesion in the fallopian tube; this observation has prompted the provocative suggestion of removing the fallopian tube to reduce ovarian cancer risk.

SUMMARY

Because of the interplay between the hormonal impact of ovarian function on breast cancer risk, the risk reduction associated with oophorectomy, and the impact of early menopause on other health outcomes, an integrated multidisciplinary approach is required to aid in the increasingly complex decisions faced by women with high inherited risk of developing gynecologic cancers.

Breast cancer under age 40: a different approach

Breast cancer (BC) under age 40 is a complex disease to manage due to the additionally fertility-related factors to be taken in consideration. More than 90% of young patients with BC are symptomatic. Women<40 years are more likely to develop BC with worse clinicopathological features and more aggressive subtype. This has been frequently associated with inferior outcomes. Recently, the prognostic significance of age<40 has been shown to differ according to the BC subtype, being associated with worst recurrence-free survival (RFS) and overall survival (OS) for luminal BC. The biology of BC<40 has also been explored through analysis of large genomic data set, and specific pathways overexpressed in these tumors have been identified which can lead to the development of targeted therapy in the future. A multidisciplinary tumor board should determine the optimal locoregional and systemic management strategies for every individual patient with BC before the start of any therapy including surgery. This applies to both early (early breast cancer (EBC)) and advanced (advanced breast cancer (ABC)) disease, before the start of any therapy. Mastectomy even in young patients confers no overall survival advantage when compared to breast-conserving treatment (BCT), followed by radiotherapy. Regarding axillary approach, indications are identical to other age groups. Young age is one of the most important risk factors for local recurrence after both breast-conserving surgery (BCS) and mastectomy, associated with a higher risk of distant metastasis and death. Radiation after BCS reduces local recurrence from 19.5 to 10.2% in BC patients 40 years and younger. The indications for and the choice of systemic treatment for invasive BC (both early and advanced disease) should not be based on age alone but driven by the biological characteristics of the individual tumor (including hormone receptor status, human epidermal growth factor receptor 2 (HER-2) status, grade, and proliferative activity), disease stage, and patient's comorbidities. Recommendations regarding the use of genomic profiles such as MammaPrint, Oncotype Dx, and Genomic grade index in young women are similar to the general BC population. Especially in the metastatic setting, patient preferences should always be taken into account, as the disease is incurable. The best strategy for these patients is the inclusion into well-designed, independent, prospective randomized clinical trials. Metastatic disease should always be biopsied whenever feasible for histological confirmation and reassessment of biology. Endocrine therapy is the preferred option for hormone receptor-positive disease (HR+ve), even in presence of visceral metastases, unless there is concern or proof of endocrine resistance or there is a need for rapid disease response and/or symptom control. Recommendations for chemotherapy (CT) should not differ from those for older patients with the same characteristics of the metastatic disease and its extent. Young age by itself should not be an indication to prescribe more intensive and combination CT regimens over the sequential use of monotherapy. Poly(ADP-ribose) polymerase inhibitors (PARP inhibitors) represent an important group of promising drugs in managing patients with breast cancer susceptibility gene (BRCA)-1- or BRCA-2-associated BC. Specific age-related side effects of systemic treatment (e.g., menopausal symptoms, change in body image, bone morbidity, cognitive function impairment, fertility damage, sexual dysfunction) and the social impact of diagnosis and treatment (job discrimination, taking care for children) should also be carefully addressed when planning systemic long-lasting therapy, such as endocrine therapy. Survivorship concerns for young women are different compared to older women, including issues of fertility, preservation, and pregnancy.

Breast cancer risks and risk prediction models

BRCA1/2 mutation carriers have a considerably increased risk to develop breast and ovarian cancer. The personalized clinical management of carriers and other at-risk individuals depends on precise knowledge of the cancer risks. In this report, we give an overview of the present literature on empirical cancer risks, and we describe risk prediction models that are currently used for individual risk assessment in clinical practice. Cancer risks show large variability between studies. Breast cancer risks are at 40-87% for BRCA1 mutation carriers and 18-88% for BRCA2 mutation carriers. For ovarian cancer, the risk estimates are in the range of 22-65% for BRCA1 and 10-35% for BRCA2. The contralateral breast cancer risk is high (10-year risk after first cancer 27% for BRCA1 and 19% for BRCA2). Risk prediction models have been proposed to provide more individualized risk prediction, using additional knowledge on family history, mode of inheritance of major genes, and other genetic and non-genetic risk factors. User-friendly software tools have been developed that serve as basis for decision-making in family counseling units. In conclusion, further assessment of cancer risks and model validation is needed, ideally based on prospective cohort studies. To obtain such data, clinical management of carriers and other at-risk individuals should always be accompanied by standardized scientific documentation.

High mobility group box-1 and its clinical value in breast cancer

BACKGROUND

High mobility group box-1 (HMGB1) is a factor regulating malignant tumorigenesis, proliferation, and metastasis, and is associated with poor clinical pathology in various human cancers. We investigated the differential concentrations of HMGB1 in tissues and sera, and their clinical value for diagnosis in patients with breast cancer, benign breast disease, and healthy individuals.

METHODS

HMGB1 levels in tumor tissues, adjacent normal tissues, and benign breast disease tissues was detected via immunohistochemistry. Serum HMGB1 was measured using an enzyme-linked immunosorbent assay in 56 patients with breast cancer, 25 patients with benign breast disease, and 30 healthy control subjects. The clinicopathological features of the patients were compared. Tissues were evaluated histopathologically by pathologists.

RESULTS

HMGB1 levels in the tissues and sera of patients with breast cancer were significantly higher than those in patients with benign breast disease or normal individuals. The 56 cancer patients were classified as having high tissue HMGB1 levels (n=41) or low tissue HMGB1 levels (n=15), but the corresponsive serum HMGB1 in these two groups was not significantly different. HMGB1 levels in breast cancer tissues significantly correlated with differentiation grade, lymphatic metastasis, and tumor-node-metastasis stage, but not patient age, tumor size, or HER-2/neu expression; no association between serum HMGB1 levels and these clinicopathological parameters was found. The sensitivity and specificity of tissue HMGB1 levels for the diagnosis of breast cancer were 73.21% and 84.00%, respectively, while positive and negative predictive values were 91.11% and 58.33%.

CONCLUSION

HMGB1 might be involved in the development and progression of breast cancer and could be a supportive diagnostic marker for breast cancer. Serum HMGB1 could be a useful serological biomarker for diagnosis and screening of breast cancer.

Breast Cancer Risk Associated with Estrogen Exposure and Truncating Mutation Location in BRCA1/2 Carriers

BACKGROUND

Mutations in BRCA1/2 confer a high risk of breast cancer, but literature values of this risk vary. A genotype-phenotype correlation has been found in both genes, and the effect of reproductive factors differs according to mutation location. Therefore, we hypothesize that such a variation may exist for other factors related to estrogen exposure.

METHODS

We used a weighted Cox regression model to assess variation in breast cancer risk with these factors using location of mutation in homogeneous breast cancer risk region of BRCA1/2 in the GENEPSO study.

RESULTS

We found that late age at menarche reduced breast cancer risk by 31% and that among BRCA1 carriers, a long or a short menstrual cycle increased risk (by 65% and 73%, respectively). Among premenopausal women, overweight was associated with a 45% decrease in risk whereas underweight was associated with an increased risk (HR, 2.40). A natural menopause, mainly after age 50, was associated with a high breast cancer risk (HR, 2.46), and a significant interaction between menopause status and the location of mutations was found leading up to 10% variation in absolute risk according to the age at menopause.

CONCLUSIONS

As observed in the general population, a late menarche, a long or a short menstrual cycle, over- or underweight, and being postmenopausal were associated with breast cancer risk in BRCA1/2 carriers. The association with the menopause was observed only when the mutation was located in the "high-risk" zones.

IMPACT

Taking into account modifier factors, location of mutation might be important for the clinical management of BRCA1/2 mutation carriers.

Abnormal expression of serum soluble E-cadherin is correlated with clinicopathological features and prognosis of breast cancer

BACKGROUND

Increased amounts of soluble E-cadherin (E-cad) have been found in the serum in various cancers, but the role of serum soluble E-cad in the prognosis of breast cancer patients has not been explored in Asian populations.

MATERIAL/METHOD

Blood samples from 111 consecutive patients diagnosed with breast cancer and 55 healthy controls were investigated.Serum soluble E-cad expression levels were measured by enzyme-linked immunosorbent assay(ELISA) with an immunoassay kit according to the manufacturer's directions. Kaplan-Meier analyses were used to evaluate the association between serum soluble E-cad expression level and survival. All statistical tests were 2-sided.

RESULTS

The serum levels of soluble E-cad in breast cancer patients were significantly higher than those of the control group (2218.9±319.6 ng/ml vs. 742.8±91.7 ng/ml, p<0.001). Serum levels of soluble E-cad correlated significantly with TNM stage (P=0.007), tumor grade (P=0.03), and lymph node metastasis (P<0.001). Kaplan-Meier analysis with the log-rank test indicated that high serum levels of soluble E-cad had a significant impact on overall survival (55.4% vs. 81.4%; P=0.032) and disease-free survival (36.8% vs. 67.8%; P=0.002) in breast cancer. Multivariate analysis revealed that serum levels of soluble E-cad were independently associated with overall survival and disease-free survival in breast cancer patients.

CONCLUSIONS

Serum soluble E-cad level is an independent prognostic factor in Asian breast cancer patients.

Factors influencing ovulation and the risk of ovarian cancer in BRCA1 and BRCA2 mutation carriers

The role of the lifetime number of ovulatory cycles has not been evaluated in the context of BRCA-associated ovarian cancer. Thus, we conducted a matched case-control study to evaluate the relationship between the cumulative number of ovulatory cycles (and contributing components) and risk of developing ovarian cancer in BRCA mutation carriers (1,329 cases and 5,267 controls). Information regarding reproductive and hormonal factors was collected from a routinely administered questionnaire. Conditional logistic regression was used to evaluate all associations. We observed a 45% reduction in the risk of developing ovarian cancer among women in the lowest vs. highest quartile of ovulatory cycles (OR = 0.55; 95% CI 0.41-0.75, p = 0.0001). Breastfeeding for more than 12 months was associated with a 38% (95% CI 0.48-0.79) and 50% (95% CI 0.29-0.84) reduction in risk among BRCA1 and BRCA2 mutation carriers, respectively. For oral contraceptive use, maximum benefit was seen with five or more years of use among BRCA1 mutation carriers (OR = 0.50; 95% CI 0.40-0.63) and three or more years for BRCA2 mutation carriers (OR = 0.42; 95% CI 0.22-0.83). Increasing parity was associated with a significant inverse trend among BRCA1 (OR = 0.87; 95% CI 0.79-0.96; p-trend = 0.005) but not BRCA2 mutation carriers (OR 0.98; 95% CI 0.81-1.19; p-trend = 0.85). A later age at menopause was associated with an increased risk in women with a BRCA1 mutation (OR trend = 1.18; 95% CI 1.03-1.35; p = 0.02). These findings support an important role of breastfeeding and oral contraceptive use for the primary prevention of ovarian cancer among women carrying BRCA mutations.

Cooperation between BRCA1 and vitamin D is critical for histone acetylation of the p21waf1 promoter and growth inhibition of breast cancer cells and cancer stem-like cells

Carriers of germline mutations in the BRCA1 gene have a significant increased lifetime risk for being diagnosed with breast cancer. The incomplete penetrance of BRCA1 suggests that environmental and/or genetic factors modify the risk and incidence among mutation carriers. Nutrition and particular micronutrients play a central role in modifying the phenotypic expression of a given genotype by regulating chromatin structure and gene expression. The active form of vitamin D, 1α,25-dihydroxyvitamin D3, is a potent inhibitor of breast cancer growth. Here we report that two non-calcemic analogues of 1α,25-dihydroxyvitamin D3, seocalcitol (EB1089) and QW-1624F2-2, collaborate with BRCA1 in mediating growth inhibition of breast cancer cells and breast cancer stem-like cells. EB1089 induces a G1/S phase growth arrest that coincides with induction of p21waf1 expression only in BRCA1-expressing cells. A complete knockdown of BRCA1 or p21waf1 renders the cells unresponsive to EB1089. Furthermore, we show that in the presence of ligand, BRCA1 associates with vitamin D receptor (VDR) and the complex co-occupies vitamin D responsive elements (VDRE) at the CDKN1A (p21waf1) promoter and enhances acetylation of histone H3 and H4 at these sites. Thus, BRCA1 expression is critical for mediating the biological impact of vitamin D3 in breast tumor cells.