Genome-Wide Association Study in BRCA1 Mutation Carriers Identifies Novel Loci Associated with Breast and Ovarian Cancer Risk

BRCA1-associated breast and ovarian cancer risks can be modified by common genetic variants. To identify further cancer risk-modifying loci, we performed a multi-stage GWAS of 11,705 BRCA1 carriers (of whom 5,920 were diagnosed with breast and 1,839 were diagnosed with ovarian cancer), with a further replication in an additional sample of 2,646 BRCA1 carriers. We identified a novel breast cancer risk modifier locus at 1q32 for BRCA1 carriers (rs2290854, P = 2.7×10-8, HR = 1.14, 95% CI: 1.09-1.20). In addition, we identified two novel ovarian cancer risk modifier loci: 17q21.31 (rs17631303, P = 1.4×10-8, HR = 1.27, 95% CI: 1.17-1.38) and 4q32.3 (rs4691139, P = 3.4×10-8, HR = 1.20, 95% CI: 1.17-1.38). The 4q32.3 locus was not associated with ovarian cancer risk in the general population or BRCA2 carriers, suggesting a BRCA1-specific associat

Discovery and characterization of novel CYP1B1 inhibitors based on heterocyclic chalcones: Overcoming cisplatin resistance in CYP1B1-overexpressing lines

© 2017 Elsevier Masson SAS The structure of alpha-napthoflavone (ANF), a potent inhibitor of CYP1A1 and CYP1B1, mimics the structure of chalcones. Two potent CYP1B1 inhibitors 7k (DMU2105) and 6j (DMU2139) have been identified from two series of synthetic pyridylchalcones. They inhibit human CYP1B1 enzyme bound to yeast-derived microsomes (Sacchrosomes™) with IC 50 values of 10 and 9nM, respectively, and show a very high level of selectivity towards CYP1B1 with respect to the IC 50 values obtained with CYP1A1, CYP1A2, CYP3A4, CYP2D6, CYP2C9 and CYP2C19 Sacchrosomes™. Both compounds also potently inhibit CYP1B1 expressed within ‘live’ recombinant yeast and human HEK293 kidney cells with IC 50 values of 63, 65, and 4, 4nM, respectively. Furthermore, the synthesized pyridylchalcones possess better solubility and lipophilicity values than ANF. Both compounds overcome cisplatin–resistance in HEK293 and A2780cells which results from CYP1B1 overexpression. These potent cell-permeable and water-soluble CYP1B1 inhibitors are likely to have useful roles in the treatment of cancer, glaucoma, ischemia and obesity

(E)-3-(3,4,5-Trimethoxyphenyl)-1-(pyridin-4-yl)prop-2-en-1-one, a heterocyclic chalcone is a potent and selective CYP1A1 inhibitor and cancer chemopreventive agent

The overexpression of CYP1 family of enzymes is reported to be associated with development of human carcinomas. It has been well reported that CYP1A1 specific inhibitors prevents carcinogenesis. Herein, thirteen pyridine-4-yl series of chalcones were synthesized and screened for inhibition of CYP1 isoforms 1A1, 1B1 and 1A2 in Sacchrosomes™ and live human HEK293 cells. The structure-activity relationship analysis indicated that chalcones bearing tri-alkoxy groups (8a and 8k) on non-heterocyclic ring displayed selective inhibition of CYP1A1 enzyme, with IC50 values of 58 and 65 nM, respectively. The 3,4,5-trimethoxy substituted derivative 8a have shown >10-fold selectivity towards CYP1A1 with respect to other enzymes of the CYP1 sub-family and >100-fold selectivity with respect to CYP2 and CYP3 family of enzymes. The potent and selective CYP1A1 inhibitor 8a displayed antagonism of B[a]P mediated activation of aromatic hydrocarbon receptor (AhR) in yeast cells, and also protected human cells from CYP1A1-mediated B[a]P toxicity in human cells. This potent and selective inhibitor of CYP1A1 enzyme have a potential for development as cancer chemopreventive agent