Clinical response of pancreatic cancer bearing a germline BRCA2 p.I3169M fs*48 variant for platinum-based drug and PARP inhibitor.

Pancreatic cancer is a malignancy with a high mortality rate, accounting for 37 000 people annually in Japan. It is rarely diagnosed in a resectable state, and effective medicines for its advanced stage are scarce. Some pancreatic cancer is hereditary, and ~10% have germline mutations of Breast cancer 1/2 (BRCA1/2). BRCA1/2 are key molecules involved in homologous recombination to repair DNA double-strand break. Platinum-based drugs and poly Adenosine diphosphate ribose (ADP) ribose polymerase inhibitors that induce synthetic lethality would be theoretically effective in patients with loss-of-function mutations in BRCA1/2. Strictly speaking, some discrepancy between the pathogenicity of BRCA1/2 and their drug sensitivity might be expected. Hence, we report that platinum-based anticancer agents and poly ADP ribose polymerase inhibitors were effective against pancreatic cancer bearing BRCA2 p.I3169M fs*48.

Implementing mainstream genetic counseling within the area-wide network of the German Consortium Hereditary Breast and Ovarian Cancer (GC-HBOC): Satisfaction of primary care providers with the provided state-of-the-art training by the Cologne Center.

The German Cancer Society (Deutsche Krebsgesellschaft DKG) has published a position paper to address the challenges of cancer patient care in the era of genomic medicine. The German Consortium Hereditary Breast and Ovarian Cancer (GC-HBOC) has implemented this recommendation in its care concept for families at risk. Core elements are the outcome-oriented evaluation of structured and standardized clinical measures and reporting recommendations derived therefrom to primary care providers and patients. A cross-sector network with certified breast cancer and gynecological cancer centers was founded in 2015, starting from the Cologne Center of the GC-HBOC. To guarantee the knowledge transfer for mainstream genetic counseling, the Cologne center has established an educational program for physicians and specialized nurses in order to pilot trans-sectoral knowledge transfer on risk assessment and risk-stratified care. It consists of face-to-face lectures with written knowledge test, attending a genetic case conference and genetic counseling sessions with the opportunity to counsel under supervision. The lectures were accompanied by a structured evaluation of the participants' satisfaction and feedback of the needs in mainstream genetic counseling. Thereby, the network ensures that genetic counseling and testing is provided according to state-of-the-art knowledge and allows physicians to participate in knowledge-generating care outside the university setting and patients to receive care close to home. After multiple feedback cycles to improve the educational program, the GC-HBOC, in cooperation with the German Cancer Society, has now adopted this concept and developed a common and uniform online curriculum funded by the Federal Ministry of Health. https://www.krebsgesellschaft.de/fortbildung-familiaerer-krebs.html.

BRCA1 Intragenic Duplication Combined with a Likely Pathogenic TP53 Variant in a Patient with Triple-Negative Breast Cancer: Clinical Risk and Management.

For patients with hereditary breast and ovarian cancer, the probability of carrying two pathogenic variants (PVs) in dominant cancer-predisposing genes is rare. Using targeted next-generation sequencing (NGS), we investigated a 49-year-old Caucasian woman who developed a highly aggressive breast tumor. Our analyses identified an intragenic germline heterozygous duplication in BRCA1 with an additional likely PV in the TP53 gene. The BRCA1 variant was confirmed by multiplex ligation probe amplification (MLPA), and genomic breakpoints were characterized at the nucleotide level (c.135-2578_442-1104dup). mRNA extracted from lymphocytes was amplified by RT-PCR and then Sanger sequenced, revealing a tandem duplication r.135_441dup; p.(Gln148Ilefs*20). This duplication results in the synthesis of a truncated and, most likely, nonfunctional protein. Following functional studies, the TP53 exon 5 c.472C > T; p.(Arg158Cys) missense variant was classified as likely pathogenic by the Li-Fraumeni Syndrome (LFS) working group. This type of unexpected association will be increasingly identified in the future, with the switch from targeted BRCA sequencing to hereditary breast and ovarian cancer (HBOC) panel sequencing, raising the question of how these patients should be managed. It is therefore important to record and investigate these rare double-heterozygous genotypes.

Informational needs of individuals from families harboring BRCA pathogenic variants: A systematic review and content analysis.

PURPOSE: Personalized information is paramount to patient-centered communication and decision-making regarding risk management in hereditary cancer syndromes. This systematic review identified information needs of individuals from families harboring BRCA pathogenic variants and compared findings based on gender (women vs men) and clinical characteristics (patients with cancer vs previvors and BRCA heterozygotes vs untested relatives). METHODS: We screened 8115 studies identified from databases and citation searching. The quality of selected studies was assessed using the Mixed Methods Appraisal Tool. Narrative synthesis was conducted based on content analysis. RESULTS: From 18 selected studies including 1063 individuals, we identified 9 categories of information needs. Risk of bias in the selected studies was moderate. Men, untested relatives, and racial and ethnic minorities were underrepresented. Frequently required information was personalized cancer risk and risk-reducing strategies, including decision-making, family implications of hereditary cancers, psychological issues, and cascade testing. Subgroup analyses showed that information needs depended on gender, personal cancer history, and cascade testing in relatives. CONCLUSION: We identified comprehensive and detailed informational needs of individuals from families harboring BRCA pathogenic variants and gaps in international guidelines. Needs for personalized information varied based on gender, health, and genetic testing status. Findings of this study have implications for genetic counseling, tailoring educational materials, and personalizing interventions.

Hereditary cancer predispositions: Comparison of multigene panel sequencing on fresh-frozen breast/ovarian tumor versus blood.

In breast or ovarian cancer (BC/OC) patients with evocative personal and/or family history, multigene panel sequencing is performed on blood to diagnose hereditary predispositions. Additionally, BRCA1/BRCA2 testing can be performed on tumor sample for therapeutic purpose. The accuracy of multigene panel tumor analysis on BC/OC to detect predisposing germline pathogenic variants (gPV) has not been precisely assessed. By comparing sequencing data from blood and fresh-frozen tumor we show that tumor genomic instability causes pitfalls to consider when performing tumor testing to detect gPV. Even if loss of heterozygosity increases germline signal in most cases, somatic copy number variants (CNV) can mask germline CNV and collapse point gPV variant allele frequency (VAF). Moreover, VAF does not allow an accurate distinction between germline and somatic pathogenic variants.

Risk-reducing salpingo-oophorectomy for Japanese women with hereditary breast and ovarian cancer: a single-institution 10-year experience.

BACKGROUND: For women diagnosed with hereditary breast and ovarian cancer, the clinical guidelines recommend risk-reducing salpingo-oophorectomy at age 35-40 years or after completion of childbearing. However, there is limited information regarding the current status of risk-reducing salpingo-oophorectomy in Japan. METHODS: To clarify factors influencing decision-making for risk-reducing salpingo-oophorectomy among Japanese women diagnosed with hereditary breast and ovarian cancer and their clinical outcomes, we analyzed the medical records of 157 Japanese women with germline BRCA pathogenic variants (BRCA1 n = 85, BRCA2 n = 71 and both n = 1) at our institution during 2011-21. Specimens obtained from risk-reducing salpingo-oophorectomy were histologically examined according to the sectioning and extensively examining the fimbriated end protocol. RESULTS: The risk-reducing salpingo-oophorectomy uptake rate was 42.7% (67/157). The median age at risk-reducing salpingo-oophorectomy was 47 years. Older age, married state and parity were significantly associated with risk-reducing salpingo-oophorectomy (P < 0.001, P = 0.002 and P = 0.04, respectively). History of breast cancer or family history of ovarian cancer did not reach statistical significance (P = 0.18 and P = 0.14, respectively). Multivariate analyses revealed that older age (≥45 years) and married state may be independent factors associated with risk-reducing salpingo-oophorectomy. Interestingly, the annual number of risk-reducing salpingo-oophorectomy peaked in 2016-17 and has increased again since 2020. The rate of occult cancers at risk-reducing salpingo-oophorectomy was 4.5% (3/67): ovarian cancer (n = 2) and serous tubal intraepithelial carcinoma (n = 1). CONCLUSION: Age and marital status significantly affected decision-making for risk-reducing salpingo-oophorectomy. This is the first study to suggest possible effects of Angelina Jolie's risk-reducing salpingo-oophorectomy in 2015 and the National Health Insurance introduced for risk-reducing salpingo-oophorectomy in 2020. The presence of occult cancers at risk-reducing salpingo-oophorectomy supports clinical guidelines recommending risk-reducing salpingo-oophorectomy at younger ages.

Advancing health equity: A qualitative study assessing barriers and facilitators of implementing hereditary breast and ovarian cancer risk screening tools in community-based organizations.

Genetic counseling and testing (GCT) inform cancer management for persons at risk for hereditary breast and ovarian cancer (HBOC). Community-based organizations (CBOs) may play a role in identifying at-risk Latinx individuals to connect them to GCT but data are lacking. Two academic centers and their four CBO partners planned to implement a validated questionnaire for HBOC risk screening ("HBOC risk screening tool"). This study aimed to assess CBO's preferences for HBOC risk screening tools, as well as the barriers and facilitators anticipated for future implementation. Pre-implementation focus groups were conducted with CBO's staff. Discussions centered on current practices to identify and refer at-risk patients. During the discussion, staff were asked to select one out of five validated HBOC risk screening tools to implement and to discuss anticipated barriers/facilitators for implementation. The four focus groups were coded and qualitative analyzed following the Consolidated Framework for Implementation Research (CFIR) and Health Equity domains. All CBOs chose the Family History Screen 7 (FHS-7). Participants (N = 35) highlighted how the FHS-7 was easy to adapt to better fit the target population and changing guidelines. They had positive attitudes toward implementing the screening tool, stressed how the culture of the organization positioned them to reach the target population, and noted barriers in different CFIR domains (e.g., low knowledge about HBOC and GCT referrals; scarce available resources). Participants pointed to barriers related to health equity domains including limited access to GCT and follow-up care for uninsured and underinsured populations, challenges obtaining accurate family history, and immigration-related barriers. CBOs highlighted the importance of partnering with other stakeholders to overcome barriers. Findings emphasize the need to develop multi-level implementation strategies to overcome barriers and leverage facilitators. This study can inform the development of implementation toolkits for CBOs to implement HBOC screening tools to advance health equity.

Preimplantation genetic testing for monogenic disorders: clinical experience with BRCA1 and BRCA2 from 2010-2021.

PURPOSE: Our aim was to describe the reproductive decisions and outcomes of BRCA-positive patients who used preimplantation genetic testing for monogenic disorders (PGT-M). METHODS: We performed a retrospective case series of all PGT-M cycles for BRCA variants between 2010-2021 at a large urban academic fertility center. All patients who underwent ≥ 1 cycle of IVF with PGT-M for BRCA1 or BRCA2 were included. The primary outcome was total number of BRCA-negative euploid embryos per patient. RESULTS: Sixty four patients underwent PGT-M for BRCA variants. Forty-five percent (29/64) were BRCA1-positive females, 27% (17/64) were BRCA2-positive females, 16% (10/64) were BRCA1-positive males, 11% (7/64) were BRCA2-positive males, and one was a BRCA1 and BRCA2-positive male. There were 125 retrieval cycles with PGT-M, and all cycles included PGT for aneuploidy (PGT-A). Eighty-six percent (55/64) of patients obtained at least one BRCA- negative euploid embryo, with median of 1 (range 0-10) BRCA-negative euploid embryo resulted per cycle and median 3 (range 0-10) BRCA-negative euploid embryos accumulated per patient after a median of 2 (range 1-7) oocyte retrievals. Sixty-four percent (41/64) of patients attempted at least one frozen embryo transfer (FET) with a total of 68 FET cycles. Fifty-nine percent (40/68) of embryos transferred resulted in live births. Subgroup analysis revealed different reproductive pathways for BRCA1-positive females, BRCA2-positive females, and BRCA1/2-positive males (p < 0.05). CONCLUSION: PGT-M is a viable option for BRCA-positive patients to avoid transmission while building their families. Most patients in our cohort achieved pregnancy with BRCA-negative euploid embryos.

Increasing referral of at-risk women for genetic counseling and BRCA testing using a screening tool in a community breast imaging center.

BACKGROUND: Genetic evaluation and testing for hereditary breast and ovarian cancer (HBOC) remain suboptimal. The authors evaluated the feasibility of using a screening tool at a breast imaging center to increase HBOC assessment referrals. METHODS: A brief questionnaire based on the National Comprehensive Cancer Network HBOC genetic counseling referral guidelines was developed and added to the standard intake forms of patients undergoing mammography at a community breast imaging center from 2012 through 2015. Patients who met the criteria in the guidelines were referred for genetic counseling. RESULTS: A total of 34,851 patients were screened during the study period, and 1246 (4%) patients were found to be eligible for referral; 245 of these patients made a genetic counseling appointment, and 142 patients received genetic counseling. Forty patients (28%) had a personal history of breast cancer but were not previously tested. Following counseling, 105 patients were tested for BRCA1/2. Eight patients (8%) tested positive for a pathogenic mutation and nine (9%) had a variant of unknown significance. Although they tested negative, many patients met the criteria to add breast magnetic resonance imaging to their screening due to greater than 20% lifetime breast cancer risk based on their family cancer history. This study led to improved clinical risk management in 67% of the patients who underwent genetic counseling. CONCLUSIONS: This study shows that large-scale screening of patients for HBOC syndromes at time of breast imaging is practical and highly feasible. The screening tool identified women with actionable BRCA1/2 mutations and mutation-negative but high-risk women, leading to significant changes in their risk management; these women would otherwise have been missed. LAY SUMMARY: Hereditary breast and ovarian cancer (HBOC) caused by pathogenic mutations in breast cancer genes (BRCA1/BRCA2) increase an individual's lifetime risk of getting HBOC. Identifying these high-risk individuals and using proven preventive clinical risk management strategies can significantly reduce their lifetime risk of HBOC. Using an innovative family cancer history questionnaire, 34,000 women were screened at a community breast imaging center, and genetic counseling and testing were provided to eligible women from the screening. Several women at high risk for HBOC were identified and this led to positive clinical risk management changes. These women would have been missed if not for intervention.

Identification of hereditary breast and ovarian cancer germline variants in Granada (Spain): NGS perspective.

The aim of this study was to assess the prevalence of germline variants in cancer-predisposing genes by either targeted (BRCA1/2) or multigene NGS panel in a high-risk Hereditary Breast and Ovarian Cancer (HBOC) cohort. Samples from 824 Caucasian probands were retrospectively collected and the impact of genetic diagnosis and genetic variants epidemiology in this cohort was evaluated. Performance of risk-reducing prophylactic measures, such as prophylactic mastectomy and/or prophylactic oophorectomy, was assessed through clinical follow-up of patients with a positive genetic result. Pathogenic variants predisposing to HBOC were identified in 11.9% (98/824) individuals at BRCA2 (47/98), BRCA1 (24/98), PALB2 (8/51), ATM (7/51), CHEK2 (6/51) MSH6, (2/51), RAD51C (2/51) and TP53 (2/386). Of them, 11 novel pathogenic variants and 12 VUS were identified, characterized, and submitted to ClinVar. Regarding clinical impact, the risk of developing basal or Her2 breast cancer was increased 15.7 times or 37.5 times for BRCA1 and MSH6 pathogenic variants respectively. On the contrary, the risk of developing basal or luminal A breast cancer was reduced to 81% or 77% for BRCA2 and BRCA1 pathogenic variants, respectively. Finally, 53.2% of individuals testing positive for class IV/V variants underwent prophylactic surgery (mastectomy, oophorectomy or both) being significantly younger at the cancer diagnosis than those undertaking prophylactic measures (p = 0.008). Of them, 8 carried a pathogenic/likely pathogenic variant in other genes different from BRCA1 and BRCA2, and the remaining (46.7%) decided to continue with clinical follow-up. No differences in pathogenicity or risk of developing cancer were found for BRCA1/2 between targeted and multigene sequencing strategies; however, NGS was able to resolve a greater proportion of high-risk patients.

Resuscitation of an exsanguinated obstetrics patient with HBOC-201: A case report.

BACKGROUND: Hemorrhagic shock is a clinically challenging disease process with high mortality. When conventional blood products are unable to be administered, oxygen-carrying blood alternatives are sometimes utilized. The international experience with this scenario is limited. We aim to add to this body of literature. STUDY DESIGN AND METHODS: This is a case report of the administration of bovine hemoglobin-based oxygen-carrying red blood cell (RBC) substitute HBOC-201 (HemoPure®) to a patient with post-partum bleeding and hemorrhagic shock because the patient declined RBC transfusion. HBOC-201 was administered with consent under a one-time Emergency Investigational New Drug (eIND) approval from the Food and Drug Administration with appropriate notification of the Institutional Review Board. RESULTS: The patient was successfully resuscitated with HBOC-201 from hemorrhagic shock. She was weaned off of vasopressor support and extubated with the recovery of her baseline mental status within 4 h. However, approximately 36 h after this, the patient developed multi-organ system dysfunction, volume overload, right heart failure and ultimately expired early on post-partum day 4. DISCUSSION: Resuscitation from hemorrhagic shock with HBOC-201 as an RBC alternative is feasible, but significant challenges remain with the management of sequelae resulting from prolonged low-flow, ischemic states as well as the significant colloid pressure and volume overload experienced after massive transfusion with an acellular colloid oxygen carrier.

A qualitative reflexive thematic analysis into the experiences of being identified with a BRCA1/2 gene alteration: "So many little, little traumas could have been avoided".

BACKGROUND: BRCA1/2 alterations increase females' lifetime breast cancer risk to 40 - 90%, ovarian cancer to 10 - 60%, and males' lifetime prostate cancer risk to ~ 10 - 25%. Psychosocial issues such as heightened distress can, therefore, occur in this population. This study aimed to explore the subjective experiences and needs of the BRCA1/2 alteration population in navigating cancer risk reduction measures. METHOD: This study aimed to explore the experiences and identify the needs of 18 BRCA1/2 alteration carriers, recruited through strategic sampling. A public and patient panel (N = 6) collaborated on study development. Data were analysed using reflexive thematic analysis. RESULTS: Two themes were identified: (i) Healthcare Services as a Burden to Navigate, and (ii) Burden Experienced Through Interactions with Healthcare Professionals. Results indicated uncertainty regarding care pathways, alongside a lack of relevant information. Participants felt unsupported by healthcare professionals, and as though healthcare professionals often perceive them as a burden. CONCLUSIONS: These findings suggest that the quality of interactions in healthcare systems are of relevance to the BRCA1/2 alteration population, and that uncertainty surrounding access to services and information is prevalent. The establishment of specialist hereditary cancer clinics could reduce such burden.

Liquid Biopsy Revealed HBOC Pedigree and Led to Medical Management Among the Relatives.

A hereditary breast and ovarian cancer (HBOC) pedigree was detected via liquid biopsy, and cancer prevention was initiated for the patient's daughter, after receiving a definitive result from BRCA genetic testing. A 48-yearold woman with ovarian cancer was administered precision medicine, which used cell-free DNA from plasma. The results revealed a pathogenic variant of BRCA1 as a presumed germline pathogenic mutation. We confirmed the germline pathological variant BRCA1 c.81-1G> A and suggested treatment with a PARP inhibitor. One of her three children had the variant, was diagnosed as an unaffected pathogenic variant carrier, and was advised to initiate surveillance.

Increased Co-Occurrence of Pathogenic Variants in Hereditary Breast and Ovarian Cancer and Lynch Syndromes: A Consequence of Multigene Panel Genetic Testing?

The probability of carrying two pathogenic variants (PVs) in dominant cancer-predisposing genes for hereditary breast and ovarian cancer and lynch syndromes in the same patient is uncommon, except in populations where founder effects exist. Two breast cancer women that are double heterozygotes (DH) for both BRCA1/BRCA2, one ovarian cancer case DH for BRCA1/RAD51C, and another breast and colorectal cancer who is DH for BRCA2/PMS2 were identified in our cohort. Ages at diagnosis and severity of disease in BRCA1/BRCA2 DH resembled BRCA1 single-carrier features. Similarly, the co-existence of the BRCA2 and PMS2 mutations prompted the development of breast and colorectal cancer in the same patient. The first BRCA1/BRCA2 DH was identified by HA-based and Sanger sequencing (1 of 623 families with BRCA PVs). However, this ratio has increased up to 2.9% (1 DH carrier vs. 103 single PV carriers) since using a custom 35-cancer gene on-demand panel. The type of cancer developed in each DH patient was consistent with the independently inherited condition, and the clinical outcome was no worse than in patients with single BRCA1 mutations. Therefore, the clinical impact, especially in patients with two hereditary syndromes, lies in genetic counseling tailor-made for each family based on the clinical guidelines for each syndrome. The number of DH is expected to be increased in the future as a result of next generation sequencing routines.

Dysregulation of the centrosome induced by BRCA1 deficiency contributes to tissue-specific carcinogenesis.

Alterations in breast cancer gene 1 (BRCA1), a tumor suppressor gene, increase the risk of breast and ovarian cancers. BRCA1 forms a heterodimer with BRCA1-associated RING domain protein 1 (BARD1) and functions in multiple cellular processes, including DNA repair and centrosome regulation. BRCA1 acts as a tumor suppressor by promoting homologous recombination (HR) repair, and alterations in BRCA1 cause HR deficiency, not only in breast and ovarian tissues but also in other tissues. The molecular mechanisms underlying BRCA1 alteration-induced carcinogenesis remain unclear. Centrosomes are the major microtubule-organizing centers and function in bipolar spindle formation. The regulation of centrosome number is critical for chromosome segregation in mitosis, which maintains genomic stability. BRCA1/BARD1 function in centrosome regulation together with Obg-like ATPase (OLA1) and receptor for activating protein C kinase 1 (RACK1). Cancer-derived variants of BRCA1, BARD1, OLA1, and RACK1 do not interact, and aberrant expression of these proteins results in abnormal centrosome duplication in mammary-derived cells, and rarely in other cell types. RACK1 is involved in centriole duplication in the S phase by promoting polo-like kinase 1 activation by Aurora A, which is critical for centrosome duplication. Centriole number is higher in cells derived from mammary tissues compared with in those derived from other tissues, suggesting that tissue-specific centrosome characterization may shed light on the tissue specificity of BRCA1-associated carcinogenesis. Here, we explored the role of the BRCA1-containing complex in centrosome regulation and the effect of its deficiency on tissue-specific carcinogenesis.

Prevalence of germline variants in consensus moderate-to-high-risk predisposition genes to hereditary breast and ovarian cancer in BRCA1/2-negative Brazilian patients.

PURPOSE: This study aimed to identify and classify genetic variants in consensus moderate-to-high-risk predisposition genes associated with Hereditary Breast and Ovarian Cancer Syndrome (HBOC), in BRCA1/2-negative patients from Brazil. METHODS: The study comprised 126 index patients who met NCCN clinical criteria and tested negative for all coding exons and intronic flanking regions of BRCA1/2 genes. Multiplex PCR-based assays were designed to cover the complete coding regions and flanking splicing sites of six genes implicated in HBOC. Sequencing was performed on HiSeq2500 Genome Analyzer. RESULTS: Overall, we identified 488 unique variants. We identified five patients (3.97%) that harbored pathogenic or likely pathogenic variants in four genes: ATM (1), CHEK2 (2), PALB2 (1), and TP53 (1). One hundred and thirty variants were classified as variants of uncertain significance (VUS), 10 of which were predicted to disrupt mRNA splicing (seven non-coding variants and three coding variants), while other six missense VUS were classified as probably damaging by prediction algorithms. CONCLUSION: A detailed mutational profile of non-BRCA genes is still being described in Brazil. In this study, we contributed to filling this gap, by providing important data on the diversity of genetic variants in a Brazilian high-risk patient cohort. ATM, CHEK2, PALB2 and TP53 are well established as HBOC predisposition genes, and the identification of deleterious variants in such actionable genes contributes to clinical management of probands and relatives.

Feedback of extended panel sequencing in 1530 patients referred for suspicion of hereditary predisposition to adult cancers.

High-throughput sequencing analysis represented both a medical diagnosis and technological revolution. Gene panel analysis is now routinely performed in the exploration of hereditary predisposition to cancer, which is becoming increasingly heterogeneous, both clinically and molecularly. We present 1530 patients with suspicion of hereditary predisposition to cancer, for which two types of analyses were performed: a) oriented according to the clinical presentation (n = 417), or b) extended to genes involved in hereditary predisposition to adult cancer (n = 1113). Extended panel analysis had a higher detection rate compared to oriented analysis in hereditary predisposition to breast / ovarian cancer (P < .001) and in digestive cancers (P < .094) (respectively 15% vs 5% and 19.3%, vs 12.5%). This higher detection is explained by the inclusion of moderate penetrance genes, as well as the identification of incident mutations and double mutations. Our study underscores the utility of proposing extended gene panel analysis to patients with suspicion of hereditary predisposition to adult cancer.

Genetic counselor approaches to BRCA1/2 direct-to-consumer genetic testing results.

The National Comprehensive Cancer Network recommends clinical-grade genetic testing to confirm commercial results from direct-to-consumer genetic testing (DTC-GT) companies and third-party interpretation (TPI) services; however, the type of confirmatory testing that genetic counselors (GCs) recommend remains uncharacterized. Therefore, we aimed to describe GCs testing strategies for patients who have already obtained DTC-GT results (23andMe) or TPI data (Promethease) that reported a BRCA1/2 pathogenic variant. We invited GCs specializing in clinical cancer genetics to complete an online survey distributed to members of the National Society of Genetic Counselors. The survey, completed by 80 respondents, contained case scenarios featuring probands with variable personal and family histories of cancer. Our results show that the majority of participating GCs have counseled patients for their health-related commercial test results; 94% have encountered patient DTC-GT reports (3 per year), and 69% have encountered patient TPI data (2 per year). Most participating GCs would recommend confirmatory clinical-grade testing for probands with a positive 23andMe BRCA1/2 result (77/80, 96%). However, there was strong variability between the type of recommended testing. Approximately 20% recommended single-site analysis, 11%-14% recommended the three Ashkenazi Jewish BRCA1/2 founder mutations, 4% recommended BRCA1/2 testing, and 61%-64% recommended multi-gene panel testing. The most commonly recommended panels were split between a breast and gynecological cancer-focused panel and a broad pan-cancer panel. The majority of participants (98%-100%) would also recommend confirmatory testing for patients with positive TPI data for BRCA1/2. Similarly, results were mixed between those who recommended targeted, single-site analysis (10%-15%) compared to a multi-gene panel (72%-83%). These data show that while most GCs were uniform in their practice of recommending confirmatory testing, they are mixed in their approach to the specific type of testing they would select. These results may help inform counseling approaches and consensus for this expanding group of patients.

BRCA1 ensures genome integrity by eliminating estrogen-induced pathological topoisomerase II-DNA complexes.

Women having BRCA1 germ-line mutations develop cancer in breast and ovary, estrogen-regulated tissues, with high penetrance. Binding of estrogens to the estrogen receptor (ER) transiently induces DNA double-strand breaks (DSBs) by topoisomerase II (TOP2) and controls gene transcription. TOP2 resolves catenated DNA by transiently generating DSBs, TOP2-cleavage complexes (TOP2ccs), where TOP2 covalently binds to 5' ends of DSBs. TOP2 frequently fails to complete its catalysis, leading to formation of pathological TOP2ccs. We have previously shown that the endonucleolytic activity of MRE11 plays a key role in removing 5' TOP2 adducts in G1 phase. We show here that BRCA1 promotes MRE11-mediated removal of TOP2 adducts in G1 phase. We disrupted the BRCA1 gene in 53BP1-deficient ER-positive breast cancer and B cells. The loss of BRCA1 caused marked increases of pathological TOP2ccs in G1 phase following exposure to etoposide, which generates pathological TOP2ccs. We conclude that BRCA1 promotes the removal of TOP2 adducts from DSB ends for subsequent nonhomologous end joining. BRCA1-deficient cells showed a decrease in etoposide-induced MRE11 foci in G1 phase, suggesting that BRCA1 repairs pathological TOP2ccs by promoting the recruitment of MRE11 to TOP2cc sites. BRCA1 depletion also leads to the increase of unrepaired DSBs upon estrogen treatment both in vitro in G1-arrested breast cancer cells and in vivo in epithelial cells of mouse mammary glands. BRCA1 thus plays a critical role in removing pathological TOP2ccs induced by estrogens as well as etoposide. We propose that BRCA1 suppresses tumorigenesis by removing estrogen-induced pathological TOP2ccs throughout the cell cycle.

Characteristics of BRCA1/2 pathogenic germline mutations in chinese NSCLC patients and a comparison with HBOC.

BACKGROUND AND PURPOSES: The pathogenic BRCA1/2 germline mutations contributed to Hereditary Breast and Ovarian Cancer (HBOC) susceptibility. The features of BRCA1/2 germline mutations in non-small cell lung cancer (NSCLC) have not been systematically studied. Here we performed the first study investigating the characteristics of pathogenic BRCA1/2 germline mutations in Chinese NSCLC patients and compared them with those from Chinese HBOC. METHODS: Information on BRCA1/2 germline mutations from 9010 Chinese NSCLC patients were collected from available studies and analyzed, and compared with the BRCA1/2 germline mutations from Chinese HBOC BRCA1/2 database (LOVD database, 20,523 patients). RESULTS: 19 (20 carriers, 0.22 %) pathogenic BRCA1 and 60 (66 carriers, 0.73 %) pathogenic BRCA2 germline mutations from NSCLC were identified. The carrier frequency of BRCA1/2 in Chinese NSCLC patients (86/9010 = 0.95 %) was significantly lower than that in Chinese breast and ovary cancer patients (1481/20,523 = 7.2 %) (P < 0.001). We found that frameshift and nonsense mutations were the predominant types of BRCA1/2 mutation in NSCLC, with no obvious hot spot mutations. No significant difference in the ratio of frameshift and nonsense mutations was found between BRCA1 and BRCA2 in NSCLC. 5 out of 19 mutations in BRCA1 and 23 out of 60 mutations in BRCA2 were novel mutations found in NSCLC that have never been reported in Chinese HBOC. A trend of higher percentage of BRCA1 nonsense mutations in the carriers was revealed in NSCLC compared with HBOC, while no such difference was found in BRCA2 in all types of mutations. CONCLUSIONS: BRCA1/2 germline mutations from NSCLC exhibited distinct characteristics compared with those from HBOC in Chinese population, including lower carrier frequency than HBOC, higher ratio of nonsense mutations and carriers than HBOC, and novel BRCA1/2 germline mutations never found in HBOC.