Bile acids upregulate BRCA1 and downregulate estrogen receptor 1 gene expression in ovarian cancer cellsJin, Qunyan; Noel, Olivier; Nguyen, Mai; Sam, Lionel; Gerhard, Glenn S.European Journal of Cancer Prevention: November 2018 - Volume 27 - Issue 6 - p 553–556 doi: 10.1097/CEJ.0000000000000398 Short Paper: Gynecological Cancer Abstract Author InformationAuthors Article MetricsMetrics Two major risk factors for ovarian cancer include loss-of-function mutations in the BRCA1 (breast cancer 1, early onset) gene and aspects of estrogen metabolism. Modulation of the levels of the normal BRCA1 allele and estrogen receptor expression may therefore be a preventive strategy. Consensus binding motifs for the bile acid-responsive transcription factor farnesoid X receptor were identified in the BRCA1 and estrogen receptor 1 (ESR1) and estrogen receptor 2 (ESR2) genes, supported by chromatin immunoprecipitation sequencing data. Two major bile acids, deoxycholic acid (DCA) and chenodeoxycholic acid (CDCA), resulted in a greater than four-fold induction of BRCA1 transcript levels at 10 μmol/l and a greater than six-fold induction at 50 μmol/l relative to untreated control OVCAR3 ovarian cancer cells. Conversely, CDCA and DCA at 10 μmol/l resulted in about a 75% decrease in ESR1 expression in response to 10 μmol/l CDCA and DCA and close to 90% reduction with 50 μmol/l CDCA and DCA. Bile acids had no effects on ESR2 gene transcript levels. The inverse regulation of BRCA1 and ESR1 gene expression in response to physiological levels of bile acids could have important implications for disease penetrance and chemoprevention strategies in carriers of BRCA1 mutations. Department of Medical Genetics and Molecular Biochemistry, Temple University School of Medicine, Philadelphia, Pennsylvania, USA Correspondence to Glenn S. Gerhard, MD, Department of Medical Genetics and Molecular Biochemistry, 960 Medical Education and Research Building (MERB), Temple University School of Medicine, 3500 N. Broad Street, Philadelphia 19140, Pennsylvania, USA Tel: +1 215 707 5415; fax: +1 215 707 9088; e-mail: gsgerhard@Temple.edu Received January 21, 2017 Accepted June 12, 2017 Copyright © 2018 Wolters Kluwer Health, Inc. All rights reserved.