title: Adipose tissue PCB levels and CYP1B1 and COMT genotypes in relation to breast cancer risk in postmenopausal Danish women.
abstract: Exposure to PCBs may be an etiologic factor for breast cancer. The cytochrome P450 1B1 (CYP1B1) and catechol-O-methyltransferase (COMT) enzymes are involved in estrogen metabolism and PCB metabolism, both of which may relate to breast cancer susceptibility. Polymorphisms in genes regulating these enzymes control efficiency. Our objective was to assess whether CYP1B1 and COMT gene polymorphisms modulate the effect of PCBs in breast cancer risk, among postmenopausal Danish women. Neither CYP1B1 Leu432Val polymorphisms nor adipose tissue PCBs were independently associated with breast cancer risk. When assessing the independent effect of the COMT Val158Met polymorphism, we observed reduced risk for breast cancer amongst hormone replacement therapy using women who were homozygous carriers of the variant allele compared with those carrying the wild-type variant (RR = 0.41; 95% CI: 0.29-0.89). We found no statistically significant interactions between any of the PCB groups and CYP1B1 or COMT polymorphisms on the risk of breast cancer.
authors.affiliation: a Danish Building Research Institute, Construction and Health, Aalborg University , Copenhagen , Denmark .
authors.forename: Elvira V
authors.initials: EV
authors.lastname: Bräuner
authors.forename: Steffen
authors.initials: S
authors.lastname: Loft
authors.forename: Anja
authors.initials: A
authors.lastname: Wellejus
authors.forename: Herman
authors.initials: H
authors.lastname: Autrup
authors.forename: Anne
authors.initials: A
authors.lastname: Tjønneland
authors.forename: Ole
authors.initials: O
authors.lastname: Raaschou-Nielsen
mesh_terms: D000273:Adipose Tissue / Q000378:metabolism*; D001189:Aryl Hydrocarbon Hydroxylases / Q000235:genetics*; D001943:Breast Neoplasms / Q000139:chemically induced* / Q000201:enzymology / Q000235:genetics; D016022:Case-Control Studies; D002394:Catechol O-Methyltransferase / Q000235:genetics*; D065633:Cytochrome P-450 CYP1B1; D003627:Data Interpretation, Statistical; D003718:Denmark; D005260:Female; D005838:Genotype; D020249:Hormone Replacement Therapy; D006801:Humans; D008875:Middle Aged; D011078:Polychlorinated Biphenyls / Q000032:analysis* / Q000493:pharmacokinetics / Q000633:toxicity; D020641:Polymorphism, Single Nucleotide; D017698:Postmenopause / Q000378:metabolism; D011446:Prospective Studies; D012306:Risk
chemical_list: D011078:Polychlorinated Biphenyls; D001189:Aryl Hydrocarbon Hydroxylases; C585496:CYP1B1 protein, human; D065633:Cytochrome P-450 CYP1B1; C588010:COMT protein, human; D002394:Catechol O-Methyltransferase