The BRCA1-Δ11q Alternative Splice Isoform Bypasses Germline Mutations and Promotes Therapeutic Resistance to PARP Inhibition and Cisplatin.

Breast and ovarian cancer patients harboring BRCA1/2 germline mutations have clinically benefitted from therapy with PARP inhibitor (PARPi) or platinum compounds, but acquired resistance limits clinical impact. In this study, we investigated the impact of mutations on BRCA1 isoform expression and therapeutic response. Cancer cell lines and tumors harboring mutations in exon 11 of BRCA1 express a BRCA1-Δ11q splice variant lacking the majority of exon 11. The introduction of frameshift mutations to exon 11 resulted in nonsense-mediated mRNA decay of full-length, but not the BRCA1-Δ11q isoform. CRISPR/Cas9 gene editing as well as overexpression experiments revealed that the BRCA1-Δ11q protein was capable of promoting partial PARPi and cisplatin resistance relative to full-length BRCA1, both in vitro and in vivo Furthermore, spliceosome inhibitors reduced BRCA1-Δ11q levels and sensitized cells carrying exon 11 mutations to PARPi treatment. Taken together, our results provided evidence that cancer cells employ a strategy to remove deleterious germline BRCA1 mutations through alternative mRNA splicing, giving rise to isoforms that retain residual activity and contribute to therapeutic resistance. Cancer Res; 76(9); 2778-90. ©2016 AACR.

Complementary and alternative medicine use among women at increased genetic risk of breast and ovarian cancer.

BACKGROUND: Complementary and alternative medicine (CAM) use is well documented among breast cancer patients and survivors, but little evidence is available to describe rates and patterns of use among women at increased genetic risk of breast cancer. METHODS: A pre-visit telephone interview was conducted to ascertain CAM use among the BRCA mutation carriers enrolled in a high-risk breast cancer screening study. Participants were asked to report on their use of thirteen therapies within the year prior to enrollment into the study. Logistic regression was used to evaluate the association between various factors and CAM use in this population. RESULTS: Among the 164 BRCA1 or BRCA2 mutation-positive (BRCA+) women in this analysis, 78% reported CAM use, with prayer and lifestyle diet being the two most commonly reported modalities. Many subjects used multiple CAM therapies, with 34% reporting use of three or more modalities. The most commonly used modalities were mind-body therapies and biologically-based practices, 61.6% and 51.8%, respectively. High-risk women were more likely to use CAM if they were older, more educated, more worried about ovarian cancer risk, or had a previous cancer diagnosis. CONCLUSION: This study suggests that the prevalence of CAM use is high among BRCA mutation carriers, with frequency of use comparable to that of breast cancer patients and survivors. Given the high prevalence of CAM use in our subjects, especially biologically-based therapies including herbal supplements, whose safety and efficacy in relation to cancer risk are unknown, our study suggests that future research is necessary to clarify these risks, and that it is important for providers to inquire about and to discuss the pros and cons of CAM use with their BRCA+ patients.

Evolution of the colored eco-genetic relationship map (CEGRM) for assessing social functioning in women in hereditary breast-ovarian (HBOC) families.

The CEGRM was initially conceived as a simple, concise, visual representation of the social interaction domains of information, tangible services and emotional exchanges (Kenen, R., & Peters, J. (2001). J Genet Counsel, 10, 289-309). A blend of the genetic pedigree, genogram, and ecomap, the CEGRM was developed to facilitate contemporary genetic counseling goals. An exploratory pilot study of 20 subjects showed that it was feasible, comfortable and efficiently accomplished, and that the process was useful both for assessment and as an intervention with study participants (Peters, J. A., Kenen, R., Giusti, R., Loud, J., Weissman, N., & Greene, M. H. (2004). Am J Med Genet Part A, 130A, 258-264). Subsequently, we have extended the CEGRM to 150 women from hereditary breast/ovarian cancer (HBOC) families; three different investigators have successfully administered this tool. The preliminary findings from the exploratory study were confirmed in the larger sample. Engaging in the interactive, insight-promoting CEGRM process provides a novel tool for assessing the social context of genetic testing, and helping high-risk women better understand and integrate genetic information into their personal and family identities, health beliefs, and decisions.