BRCA2 mutations and triple-negative breast cancer

Genetic/Familial High-Risk Assessment: Breast, Ovarian, and Pancreatic, Version 2.2021, NCCN Clinical Practice Guidelines in Oncology

The NCCN Guidelines for Genetic/Familial High-Risk Assessment: Breast, Ovarian, and Pancreatic focus primarily on assessment of pathogenic or likely pathogenic variants associated with increased risk of breast, ovarian, and pancreatic cancer and recommended approaches to genetic testing/counseling and management strategies in individuals with these pathogenic or likely pathogenic variants. This manuscript focuses on cancer risk and risk management for BRCA-related breast/ovarian cancer syndrome and Li-Fraumeni syndrome. Carriers of a BRCA1/2 pathogenic or likely pathogenic variant have an excessive risk for both breast and ovarian cancer that warrants consideration of more intensive screening and preventive strategies. There is also evidence that risks of prostate cancer and pancreatic cancer are elevated in these carriers. Li-Fraumeni syndrome is a highly penetrant cancer syndrome associated with a high lifetime risk for cancer, including soft tissue sarcomas, osteosarcomas, premenopausal breast cancer, colon cancer, gastric cancer, adrenocortical carcinoma, and brain tumors.

Advanced Breast Cancer at Diagnosis: Over One Third Adherent to Screening Recommendations

Background: Advanced breast cancer (ABC) at diagnosis carries a worse prognosis, and can be attributed to delay in diagnosis, failure of screening tests, or aggressive biology. Better understanding of factors related with ABC at diagnosis could help decrease the proportion of such cases.

Patients and Methods: This is a retrospective study of all patients diagnosed and treated for breast cancer (BC) at a single institution between 2012 and 2015. Data were collected from medical records and phone interviews, and included demographic, clinical, and tumor-related data, and adherence to screening recommendations.

Results: Of 555 newly diagnosed BC patients, 390 (70.3%) were diagnosed early (stage 0–IIa), and 165 (29.7%) were diagnosed with ABC (stage IIb–IV). Of the165 patients diagnosed with ABC, 57 (34.5%) underwent screening mammography as recommended. More patients with ABC were <50 years (29.1% vs. 19%, p = 0.006). ABC was associated with higher grade, higher proliferation rate, Her2/neu overexpression, luminal B-like, and triple negative phenotypes. Mammography within 30 months of diagnosis was more prevalent among those diagnosed early (64.6% vs. 34.5%, p = 0.003). Only 31 (18.8%) of the screening eligible patients who were diagnosed at advanced stage did not adhere to screening recommendations.

Conclusions: ABC at diagnosis is related to aggressive tumor biology and age <50 years. It is also associated with lower adherence to screening mammography; however, more than one third of patients diagnosed with ABC who were eligible for screening underwent screening mammography as recommended. Further research is needed to elucidate factors related with ABC at diagnosis, review screening guidelines, and develop more effective screening modalities.

Prospective Evaluation of Universal BRCA Testing for Women With Triple-Negative Breast Cancer

Background

Limited published literature exists on women with triple-negative breast cancer (TNBC) diagnosed over the age of 60 years with breast cancer gene (BRCA) pathogenic variants. Our study determined whether the rate of BRCA pathogenic variants in a prospective cohort of TNBC patients outside the definition of current clinical genetic testing (GT) guidelines warrants a change in recommendations.

Methods

A prospective study of 395 women with TNBC underwent genetic counseling and 380 (96.2%) underwent clinical BRCA GT regardless of age of diagnosis beginning January 2014 to October 2015 at The University of Texas MD Anderson Cancer Center, Houston. TNBC patients older than 60 years who did not meet clinical GT guidelines had comprehensive sequencing and large rearrangement GT as part of the research protocol.

Results

Fifty-one of 380 (13.4%) women with TNBC who underwent clinical BRCA GT were BRCA positive. Of the 86 patients diagnosed at age over 60 years and underwent GT, only two (2.3%) were positive for BRCA. These two patients would have met clinical testing criteria due to family or ancestral history.

Conclusions

Our study does not support universal BRCA testing for TNBC patients diagnosed older than 60 years as their only risk factor for a BRCA pathogenic variant. Both of the positive BRCA patients older than 60 years identified would have met current National Comprehensive Cancer Network criteria for testing. Therefore, our study demonstrates that the National Comprehensive Cancer Network guidelines provide sufficient criteria for identifying BRCA pathogenic variants in women with TNBC at 60 years or younger.

Differential Profile of BRCA1 vs. BRCA2 Mutated Families: A Characterization of the Main Differences and Similarities in Patients

The identification of families at-risk for hereditary breast cancer (BC) is important because affected individuals present a much higher cancer risk than the general population. The aim of this study was to identify the most important factors associated with the presence of a pathogenic BRCA1/BRCA2 mutation. Family history (FH), histopathological and immunohistochemical characteristics were compared among BC women with pathogenic BRCA1/BRCA2 variants; VUSs in BRCA1/BRCA2; BRCA1/BRCA2 WT and sporadic BC. The most significative differences observed concerned the molecular subtype of the tumors, age at cancer diagnosis and FH of cancer. The presence of bilateral breast cancer (BBC), number of BC cases and the presence of ovarian cancer (OC) increased (respectively) 5.797, 5.033 and 4.412 times the risk of being a BRCA1/BRCA2 mutation carrier. Besides, women with BRCA1 or BRCA2 mutations presented different tumor and FH profiles. The main characteristics associated with a BRCA1 mutation were triple negativity (OR: 17.31), BBC history (OR: 4.96) and occurrence of OC (OR: 4.32). There were no major discerning components associated with BRCA2 mutations. Thus, we conclude that tumor pathology and FH of cancer might be considered together at the time of genetic testing mainly in countries where access to genetic testing is still restricted.

BRCA1 and BRCA2 Germline Mutation Analysis in Hereditary Breast/Ovarian Cancer Families from the Aures Region (Eastern Algeria): First Report

Breast cancer is currently the leading cause of cancer morbidity and mortality among Algerian women. In this study, we aimed to investigate the mutation spectrum of BRCA1 and BRCA2 genes in hereditary breast/ovarian cancer (HBOC) families from the Aures region (eastern Algeria). High risk breast/ovarian cancer families were selected from overall 1162 consecutive patients collected from cancer registry of anticancer center of Batna. Breast cancers were diagnosed between 2011 and 2015. Recurrent mutations on BRCA1 and BRCA2 previously found in Algerian patients were screened using PCR-direct sequencing in 113 HBOC families. In addition, for the first time in Algeria, HBOC patients were analyzed by NGS using a cancer panel of 30 hereditary cancer genes or BRCA1/2 genetic test. Six distinct deleterious mutations in BRCA1 and BRCA2 and a new VUS in PALB2 were detected in ten patients. Two distinct BRCA2 pathogenic variants c.1813dupA and c.8485C > T detected in two young female triple negative breast cancer (TNBC) patients, respectively, with a family history of male breast cancer, are reported here for the first time in Algerian population. Interestingly, we also detected a BRCA exon 15 deletion in two unrelated young female TNBC patients with strong family history of breast/ovarian cancer. Our study showed differences in the distribution of the mutation spectrum of BRCA genes between the Aures region and the north central region of Algeria. Our results will contribute in the implementation of genetic counseling and testing for patients and families at risk of hereditary breast and ovarian cancer.

Inhibition of mTOR downregulates expression of DNA repair proteins and is highly efficient against BRCA2-mutated breast cancer in combination to PARP inhibition

Breast cancer is a complex disease in which each patient could present several genetic alterations that are therapeutically relevant in cancers. Here we explored the therapeutic benefit of combining PARP and mTOR inhibitors in a context of DNA repair deficiency and PI3K pathway activation.

The combination of everolimus and olaparib was tested in BRCA2-mutated patient-derived xenografts (PDX) carrying alterations in the PI3K/AKT/mTOR pathway. An RPPA analysis of different signalling pathways was performed in untreated and treated xenografts.

Everolimus and olaparib showed marked anti-tumor activities in the monotherapy setting and high efficacy when given in combination with 100% of mice showing tumor regressions. The fraction of P-H2AX positive cells was increased in both monotherapy arms and strongly increased in the combination setting. Everolimus given as monotherapy resulted in downregulation of different proteins involved in DNA damage repair, including FANCD2, RAD50 and SUV39H1. In the combination setting, expression of these proteins was almost completely abolished, suggesting convergence of PARP and mTOR in downregulation of DNA damage repair components.

In conclusion, our results suggest that combining mTOR and DNA repair inhibition could be a successful strategy to treat a subset of breast cancer with BRCA2 mutation and alterations in the PI3K/AKT/mTOR pathway.

Adjuvant versus neoadjuvant chemotherapy in triple-negative breast cancer patients with BRCA mutations

PURPOSE

As triple-negative breast cancers are associated with earlier recurrences and poorer survival, optimal treatment of early-stage breast cancer is essential. Several retrospective studies in triple-negative breast cancer have reported conflicting results in overall survival in patients receiving neoadjuvant or adjuvant systemic therapy. This study aims to analyze outcomes of adjuvant versus neoadjuvant in patients with early-stage triple-negative breast cancer with and without BRCA germline mutations.

METHODS

Patients with stage I or II triple-negative breast cancer who had BRCA testing were identified from a prospective cohort study of 4027 patients. Clinical, demographic, genetic test results, chemotherapy, recurrence, and survival data were analyzed. Overall survival and disease-free survival were estimated using the Kaplan-Meier method.

RESULTS

319 patients with stage I and II triple-negative breast cancer who met eligibility criteria were included in the analysis. 187 received adjuvant chemotherapy (58.6%) and 132 received neoadjuvant chemotherapy (41.4%). 135 were BRCA positive (42.3%) and 184 were BRCA negative (57.7%). There was no significant association between overall survival or disease-free survival and treatment with neoadjuvant versus adjuvant in the overall cohort. Furthermore, there were no significant differences between patient subgroups (neoadjuvant BRCA positive, neoadjuvant BRCA negative, adjuvant BRCA positive, and adjuvant BRCA negative) with respect to either overall survival or disease-free survival.

CONCLUSIONS

Neoadjuvant versus adjuvant with standard anthracycline- and taxane-containing regimens results in similar disease-free survival and overall survival among patients with stage I and II triple-negative breast cancer regardless of BRCA status. Further studies are needed to evaluate whether similar results are observed with newer agents.

Morphometric analysis of a triple negative breast cancer cell line in hydrogel and monolayer culture environments

Triple negative breast cancer (TNBC) is a belligerent carcinoma that is unresponsive to targeted receptor therapies. Development of new treatment strategies would benefit from an expanded repertoire of in vitro cell culture systems, such as those that support tridimensional growth in the presence of hydrogel scaffolds. To this end, we established protocols for maintenance of the TNBC cell line HCC70 in monolayer culture and in a commercially available basement membrane matrix hydrogel. We evaluated the general morphology of cells grown in both conditions with light microscopy, and examined their subcellular organization using transmission electron microscopy (TEM). Phase contrast and confocal microscopy showed the prevalence of irregularly shaped flattened cells in monolayer cultures, while cells maintained in hydrogel organized into multi-layered spheroids. A quantitative ultrastructural analysis comparing cells from the two culture conditions revealed that cells that formed spheroids comprised a greater number of mitochondria, autophagic vacuoles and intercellular junctions than their monolayer counterparts, within the equivalent area of sampled tissue. These observations suggest that triple negative breast cancer cells in culture can alter their organelle content, as well as their morphology, in response to their microenvironment. Methods presented here may be useful for those who intend to image cell cultures with TEM, and for investigators who seek to implement diverse in vitro models in the search for therapeutic molecular targets for TNBC.

Opportunities for improving triple-negative breast cancer outcomes: results of a population-based study

Triple‐negative breast cancer (TNBC) is associated with a poor prognosis. Surgery, radiotherapy, chemotherapy, and referral for genetic counseling are the standard of care. We assessed TNBC prevalence, management, and outcome using data from the population‐based Geneva cancer registry. 2591 women had a first invasive stage I‐III breast cancer diagnosed between 2003 and 2011. We compared TNBC to other breast cancers (OBC) by χ²‐test and logistic regression. Kaplan–Meier survival curves, up to 31‐12‐2014, were compared using log‐rank test. TNBC risk of mortality overall (OS) and for breast cancer (BCSS) was evaluated through Cox models. Linkage with the Oncogenetics and Cancer Prevention Unit (OCPU) database of the Geneva University Hospitals provided genetic counseling information. TNBC patients (n = 192, 7.4%) were younger, more often born in Africa or Central‐South America than OBC, had larger and more advanced tumors. 18% of TNBC patients did not receive chemotherapy. Thirty‐one (17%) TNBC women consulted the OCPU, 39% among those aged <40 years. Ten‐year survival was lower in TNBC than OBC (72% vs. 82% for BCSS; P < 0.001; 80% vs. 91% for OS; P < 0.001). The mortality risks remained significant after adjustment for other prognostic variables. The strongest determinants of mortality were age, place of birth, and lymph node status. A substantial proportion of TNBC patients in Geneva did not receive optimal care. Over 60% of eligible women did not receive genetic counseling and 18% did not receive chemotherapy. To improve TNBC prognosis, comprehensive care as recommended by standard guidelines should be offered to all patients.

High prevalence and predominance of BRCA1 germline mutations in Pakistani triple-negative breast cancer patients

BACKGROUND

Women harboring BRCA1/2 germline mutations have high lifetime risk of developing breast/ovarian cancer. The recommendation to pursue BRCA1/2 testing is based on patient's family history of breast/ovarian cancer, age of disease-onset and/or pathologic parameters of breast tumors. Here, we investigated if diagnosis of triple-negative breast cancer (TNBC) independently increases risk of carrying a BRCA1/2 mutation in Pakistan.

METHODS

Five hundred and twenty-three breast cancer patients including 237 diagnosed ≤ 30 years of age and 286 with a family history of breast/ovarian cancer were screened for BRCA1/2 small-range mutations and large genomic rearrangements. Immunohistochemical analyses were performed at one center. Univariate and multiple logistic regression models were used to investigate possible differences in prevalence of BRCA1/2 mutations according to patient and tumor characteristics.

RESULTS

Thirty-seven percent of patients presented with TNBC. The prevalence of BRCA1 mutations was higher in patients with TNBC than non-TNBC (37 % vs. 10 %, P < 0.0001). 1 % of TNBC patients were observed to have BRCA2 mutations. Subgroup analyses revealed a larger proportion of BRCA1 mutations in TNBC than non-TNBC among patients 1) diagnosed at early-age with no family history of breast/ovarian cancer (14 % vs. 5 %, P = 0.03), 2) diagnosed at early-age irrespective of family history (28 % vs. 11 %, P = 0.0003), 3) had a family history of breast cancer (49 % vs. 12 %, P < 0.0001), and 4) those with family history of breast and ovarian cancer (81 % vs. 28 %, P = 0.0005). TNBC patients harboring BRCA1 mutations were diagnosed at a later age than non-carriers (median age at diagnosis: 30 years (range 22-53) vs. 28 years (range 18-67), P = 0.002). The association between TNBC status and presence of BRCA1 mutations was independent of the simultaneous consideration of family phenotype, tumor histology and grade in a multiple logistic regression model (Ratio of the probability of carrying BRCA1/2 mutations for TNBC vs. non-TNBC 4.23; 95 % CI 2.50-7.14; P < 0.0001).

CONCLUSION

Genetic BRCA1 testing should be considered for Pakistani women diagnosed with TNBC.

Increased ID4 expression, accompanied by mutant p53 accumulation and loss of BRCA1/2 proteins in triple-negative breast cancer, adversely affects survival

AIMS

Breast cancer 1 (BRCA1) expression is down-regulated in a significant proportion of non-hereditary breast cancers, in the absence of any mutation. This phenomenon is more pronounced in oestrogen (ER)-negative tumours. Recent studies have suggested that inhibitor of DNA binding 4 (ID4), as well as p53, participate in the transcriptional regulation of BRCA1.

METHODS

Immunohistochemical expression of ID4, BRCA1, BRCA2 and p53 in 699 women with triple-negative breast cancer was investigated using tissue microarrays. The prognostic role of these biomarkers was also evaluated. Survival outcomes were estimated with the Kaplan-Meier method and compared between groups with log-rank statistics.

RESULTS

Loss of BRCA1 and BRCA2 expression and overexpression of ID4 and p53 was observed in 75%, 90%, 95% and 66% of tumours, respectively. ID4 expression was increased in higher tumour grade (P < 0.001) and was associated significantly with basal-like subtype (P < 0.001), BRCA2 down-regulation (P = 0.037) and p53 accumulation (P < 0.001). Patients with strong ID4 expression displayed worse disease-free survival in both triple-negative breast cancers (P = 0.041) and basal-like triple-negative breast cancers (P = 0.026).

CONCLUSION

There is frequent ID4 expression and concomitant loss of BRCA proteins in triple-negative breast cancer. We hypothesize that strong ID4 expression could be useful as a prognostic marker in triple-negative breast cancer, predicting early tumour recurrence.

Predictive Factors for BRCA1 and BRCA2 Genetic Testing in an Asian Clinic-Based Population

Purpose

The National Comprehensive Cancer Network (NCCN) has proposed guidelines for the genetic testing of the BRCA1 and BRCA2 genes, based on studies in western populations. This current study assessed potential predictive factors for BRCA mutation probability, in an Asian population.

Methods

A total of 359 breast cancer patients, who presented with either a family history (FH) of breast and/or ovarian cancer or early onset breast cancer, were accrued at the National Cancer Center Singapore (NCCS). The relationships between clinico-pathological features and mutational status were calculated using the Chi-squared test and binary logistic regression analysis.

Results

Of 359 patients, 45 (12.5%) had deleterious or damaging missense mutations in BRCA1 and/or BRCA2. BRCA1 mutations were more likely to be found in ER-negative than ER-positive breast cancer patients (P=0.01). Moreover, ER-negative patients with BRCA mutations were diagnosed at an earlier age (40 vs. 48 years, P=0.008). Similarly, triple-negative breast cancer (TNBC) patients were more likely to have BRCA1 mutations (P=0.001) and that these patients were diagnosed at a relatively younger age than non-TNBC patients (38 vs. 46 years, P=0.028). Our analysis has confirmed that ER-negative status, TNBC status and a FH of hereditary breast and ovarian cancer (HBOC) are strong factors predicting the likelihood of having BRCA mutations.

Conclusions

Our study provides evidence that TNBC or ER-negative patients may benefit from BRCA genetic testing, particularly younger patients (<40 years) or those with a strong FH of HBOC, in Asian patients.

Evaluation of BRCA1/2 mutational status among German and Austrian women with triple-negative breast cancer

PURPOSE

Testing for BRCA1 and BRCA2 mutations in breast cancer patients is used to identify the risk of second primary cancers and the risk of cancer in the patients' family. Women with triple-negative breast cancer (TNBC) are thought to be more likely to be BRCA1/2 mutation carriers, but most national guidelines for genetic testing, including those used in Germany and Austria, do not consider receptor triple negativity.

METHODS

We determined the prevalence of BRCA1 and BRCA2 mutations within a cohort of 100 unselected TNBC cases, including patients from Germany and Austria to identify those BRCA-positive patients with a masked family history and who would have been missed due to respective current national guidelines. Double-stranded Sanger sequencing of all exons of BRCA1 and BRCA2, respectively, was performed.

RESULTS

We identified a total of 13 deleterious mutations in BRCA1 and a total of four deleterious mutations in BRCA2. The total rate of deleterious BRCA1/2 mutation carriers was 21 % in our cohort. Six novel mutations, including two deleterious mutations, have been identified, which have not been described in public mutation databases so far. According to current German and Austrian national guidelines for genetic testing, 38.1 and 52.4 %, respectively, of BRCA1/2 mutation carriers would have been overlooked.

CONCLUSIONS

We conclude that the prevalence of BRCA1 and BRCA2 mutations is high in TNBC patients and that BRCA1/2 mutations are not restricted to young women or patients with a positive family history. Receptor triple negativity should therefore be considered in BRCA1/2 genetic testing guidelines.

Triple-negative breast cancer: investigating potential molecular therapeutic target

INTRODUCTION

Triple-negative breast cancer (TNBC) makes up about 10 - 20% of all breast cancers and the lack of hormone receptors and human epidermal growth factor receptor-2/Neu expression is responsible for poor prognosis, no targeted therapies and trouble in the clinical management. Tumor heterogeneity, also within the same tumor, is a major cause for this difficulty. Based on the introduction of new biological drugs against different kinds of tumor, many efforts have been made for classification of genetic alterations present in TNBC, leading to the identification of several oncogenes and tumor suppressor genes involved in breast cancer carcinogenesis.

AREAS COVERED

In this review we investigated the molecular alteration present in TNBC which could lead to the creation of new targeted therapies in the future, with the aim to counteract this disease in the most effective way.

EXPERT OPINION

In this context some hormone receptors like G-protein-coupled receptor 30 and androgen receptors may be a fascinating area to investigate; also, angiogenesis, represented not only by the classical VEGF/VEGFR relationship, but also by other molecules, like semaphorins, fibroblast growth factor and heparin-binding-EGF-like, is a mechanism in which new developments are expected. In this perspective, one technique that may show promise is the gene therapy; in particular the gene transfer could correct abnormal genetic function in cancer cells.

Germline BRCA mutation evaluation in a prospective triple-negative breast cancer registry: implications for hereditary breast and/or ovarian cancer syndrome testing

NCCN guidelines recommend genetic testing for all triple-negative breast cancer (TNBC) patients aged ≤60 years. However, due to the lack of prospective information in unselected patients, these guidelines are not uniformly adopted by clinicians and insurance carriers. The aim of this study was to determine the prevalence of BRCA mutations and evaluate the utility of NCCN guidelines in unselected TNBC population. Stage I-IV TNBC patients were enrolled on a prospective registry at academic and community practices. All patients underwent BRCA1/2 testing. Significant family history (SFH) was defined >1 relative with breast cancer at age ≤50 or ≥1 relative with ovarian cancer. Mutation prevalence in the entire cohort and subgroups was calculated. 207 TNBC patients were enrolled between 2011 and 2013. Racial/ethnic distribution: Caucasian (80 %), African-American (14 %), Ashkenazi (1 %). Deleterious BRCA1/2 mutations were identified in 15.4 % (32/207) of patients (BRCA1:11.1 %, BRCA2:4.3 %). SFH reported by 36 % of patients. Mutation prevalence in patients with and without SFH was 31.6 and 6.1 %, respectively. When assessed by age at TNBC diagnosis, the mutation prevalences were 27.6 % (≤50 years), 11.4 % (51-60 years), and 4.9 % (≥61 years). Using SFH or age ≤50 as criteria, 25 and 34 % of mutations, respectively, were missed. Mutation prevalence in patients meeting NCCN guidelines was 18.3 % (32/175) and 0 % (0/32) in patients who did not meet guidelines (p = .0059). In this unselected academic and community population with negligible Ashkenazi representation, we observed an overall BRCA mutation prevalence rate of 15.4 %. BRCA testing based on NCCN guidelines identified all carriers supporting its routine application in clinical practice for TNBC.

Triple-negative breast cancer frequency and type of BRCA mutation: Clues from Sardinia

Germline mutations in BRCA1 or BRCA2 genes have been demonstrated to increase the risk of developing breast cancer. Among the prognostic factors currently used in clinical practice, the disease stage and the receptor status play a crucial role in the management of breast carcinoma. Triple-negative breast cancer (TNBC) has been classified as a disease subgroup that is negative for oestrogen, progesterone and HER2 receptor expression, and presents a poor prognosis. The present study investigated the correlation between BRCA1/2 mutations and TNBC status in a large series (n=726) of breast cancer patients from Sardinia. The BRCA mutation screening was performed on genomic DNA from peripheral blood samples by denaturing high-performance liquid chromatography analysis and automated DNA sequencing. Overall, 21/726 (2.9%) patients carried a germline mutation in BRCA1 or BRCA2. The TNBC phenotype was significantly associated with the BRCA1 mutations (P<0.001), whereas no association was found with the BRCA2 mutations (P=0.837). With respect to patient origin within Sardinia, a significant inverse distribution of mutations was found; BRCA1 and BRCA2 mutations represented 86 and 93% of the mutated cases in Southern and Middle-Northern Sardinia, respectively (P<0.001). Patients from the geographical area with BRCA1 mutation prevalence presented a TNBC incidence much higher than that observed in cases from the area with BRCA2 mutation prevalence (12 vs. 4%, respectively; P=0.037). These findings further confirmed that the occurrence of TNBC is significantly associated with the BRCA1 mutation carrier status and that a different ‘genetic background’ may have a phenotypic impact in the onset of breast cancer.

A fragmented alignment method detects a putative phosphorylation site and a putative BRC repeat in the Drosophila melanogaster BRCA2 protein

Mutations in the BRCA2 tumor suppressor protein leave individuals susceptible to breast, ovarian and other cancers. The BRCA2 protein is a critical component of the DNA repair pathways in eukaryotes, and also plays an integral role in fostering genomic variability through meiotic recombination. Although present in many eukaryotes, as a whole the BRCA2 gene is weakly conserved. Conserved fragments of 30 amino acids (BRC repeats), which mediate interactions with the recombinase RAD51, helped detect orthologs of this protein in other organisms. The carboxy-terminal of the human BRCA2 has been shown to be phosphorylated by checkpoint kinases (Chk1/Chk2) at T3387, which regulate the sequestration of RAD51 on DNA damage. However, apart from three BRC repeats, the Drosophila melanogaster gene has not been annotated and associated with other functionally relevant sequence fragments in human BRCA2. In the current work, the carboxy-terminal phosphorylation threonine site (E=9.1e-4) and a new BRC repeat (E=17e-4) in D. melanogaster has been identified, using a fragmented alignment methodology (FRAGAL). In a similar study, FRAGAL has also identified a novel half-a- tetratricopeptide (HAT) motif (E=11e-4), a helical repeat motif implicated in various aspects of RNA metabolism, in Utp6 from yeast. The characteristic three aromatic residues with conserved spacing are observed in this new HAT repeat, further strengthening my claim. The reference and target sequences are sliced into overlapping fragments of equal parameterized lengths. All pairs of fragments in the reference and target proteins are aligned, and the gap penalties are adjusted to discourage gaps in the middle of the alignment. The results of the best matches are sorted based on differing criteria to aid the detection of known and putative sequences. The source code for FRAGAL results on these sequences is available at https://github.com/sanchak/FragalCode, while the database can be accessed at www.sanchak.com/fragal.html.

Intrafamilial disclosure of risk for hereditary breast and ovarian cancer: points to consider

The primary goal of breast and ovarian cancer screening is to minimize the cases of advanced disease and therefore its mortality rate. For hereditary breast and ovarian cancer, one method to reach this goal is to disseminate genetic risk information among family members. However, experience tells us that this information does not always reach family members in a timely manner, if at all. There are many moving parts to a decision to disclose genetic risk information within a family, and the lack of detail and cohesion in current guidelines do a disservice to hereditary breast cancer prevention. Utilizing legal, medical, and policy databases for literature, case law and policy documents relating to communication of genetic test results within families, as well as a consultative process with representative stakeholders, a points to consider has been developed to address a number of issues that might impact the ability and willingness of patients to inform family members of genetic risk. These include: what is "genetic information"; who is the "family"; why should patients inform their family members; and how should health professionals be involved in this process? This represents only an initial step towards fostering better communication within families. Additional research is needed to determine the best methods for encouraging this communication and motivations for disclosing or not and to promote the development of a solution, considering the complexity of human relationships and the probabilistic nature of genetic information.

Mutation analysis of BRCA1, BRCA2, PALB2 and BRD7 in a hospital-based series of German patients with triple-negative breast cancer

Triple-negative breast cancer (TNBC) is an aggressive form of breast carcinoma with a poor prognosis. Recent evidence suggests that some patients with TNBC harbour germ-line mutations in DNA repair genes which may render their tumours susceptible to novel therapies such as treatment with PARP inhibitors. In the present study, we have investigated a hospital-based series of 40 German patients with TNBC for the presence of germ-line mutations in BRCA1, BRCA2, PALB2, and BRD7 genes. Microfluidic array PCR and next-generation sequencing was used for BRCA1 and BRCA2 analysis while conventional high-resolution melting and Sanger sequencing was applied to study the coding regions of PALB2 and BRD7, respectively. Truncating mutations in BRCA1 were found in six patients, and truncating mutations in BRCA2 and PALB2 were detected in one patient each, whereas no truncating mutation was identified in BRD7. One patient was a double heterozygote for the PALB2 mutation, c.758insT, and a BRCA1 mutation, c.927delA. Our results confirm in a hospital-based setting that a substantial proportion of German TNBC patients (17.5%) harbour germ-line mutations in genes involved in homology-directed DNA repair, with a preponderance of BRCA1 mutations. Triple-negative breast cancer should be considered as an additional criterion for future genetic counselling and diagnostic sequencing.

CD74: a potential novel target for triple-negative breast cancer

The expression status of CD74 in breast cancer stem cells and its clinical implications was evaluated in order to lay a foundation for managing breast cancer. Five hundred and eighty breast cancer specimens were enrolled in the study. The relationship between the CD74 protein and clinicopathological parameters as well as prognosis was subsequently determined. In total, 468 (80.69 %) of the 580 breast cases showed CD74-positive expression. After universal analysis, CD74 was observed to be related to lymph node metastasis and triple-negative breast cancer (P = 0.01 and 0.001). Moreover, CD74 expression has a line correlation with lymph node metastasis and triple-negative breast cancer (P = 0.02 and 0.001). Furthermore, periostin was shown to attain a significantly more distant liver metastasis and worse disease-specific survival than those with none or low-expressed CD74 protein (P = 0.001). In the Cox regression test, CD74 protein was detected as an independent prognostic factor (P = 0.001). CD74 is consistently expressed in triple-negative subgroups of breast cancer and might be a new potential marker for triple-negative breast cancer.

Systemic therapy options in BRCA mutation-associated breast cancer

BRCA mutation-associated breast cancers are characterized by deficient homologous recombination of DNA, and 80 % of BRCA1-associated breast cancers display the basal-like molecular subtype. Traditionally, BRCA carriers have received conventional systemic chemotherapy based on their baseline tumor characteristics, and it is generally accepted that after the appropriate treatment the prognosis of a mutation carrier is equivalent to that of a patient with sporadic breast cancer. However, with the growing understanding of the functions of BRCA1/2 proteins in homologous DNA repair, it is recognized that BRCA-associated breast cancer tumors may have distinct biochemical characteristics and thus require tailored treatment strategies. Tumors arising in patients with BRCA mutations were shown to be particularly sensitive to platinum compounds or inhibitors of poly(ADP-ribose) polymerase. In addition, BRCA1-mutation carriers seem to benefit from anthracycline-taxane-containing regimens as much as sporadic triple-negative breast cancers do. In this article, we review the functions of the BRCA1 and BRCA2 genes, and their differential chemosensitivity in both the preclinical and clinical settings. The optimal chemotherapy regimen for this subset of patients still remains to be determined.