title: Serum polychlorinated biphenyls, cytochrome P-450 1A1 polymorphisms, and risk of breast cancer in Connecticut women.
abstract: Recent epidemiologic studies have suggested that genetic polymorphisms in the cytochrome P-450 1A1 gene (CYP1A1) may affect the relation between environmental exposure to polychlorinated biphenyls (PCBs) and breast cancer risk. The authors report results from a case-control study evaluating the potential effect of gene-environment interaction between CYP1A1 and serum PCB levels on breast cancer risk among Caucasian women in Connecticut. The study included 374 case women with histologically confirmed breast cancer and 406 noncancerous controls with information on both serum PCB level and CYP1A1 genotype (1999-2002). Compared with women who had the homozygous wild-type CYP1A1 m2 genotype, significantly increased risks of breast cancer were found for women with the CYP1A1 m2 variant genotype (odds ratio (OR) = 2.1, 95% confidence interval (CI): 1.1, 3.9), especially postmenopausal women (OR = 2.4, 95% CI: 1.1, 5.0). Risks associated with the CYP1A1 m2 variant genotype were highest for all women (OR = 3.6, 95% CI: 1.5, 8.2) and postmenopausal women (OR = 4.3, 95% CI: 1.6, 12.0) with higher serum PCB levels (611-2,600 ng/g). The CYP1A1 m1 and m4 genotypes were not associated with breast cancer risk independently or in combination with PCB exposure. In summary, the CYP1A1 m2 genetic polymorphism was associated with increased risk of female breast cancer and may modify the relation between PCB exposure and breast cancer risk.
authors.affiliation: Department of Epidemiology and Public Health, School of Medicine, Yale University, New Haven, CT 06510, USA.
authors.forename: Yawei
authors.initials: Y
authors.lastname: Zhang
authors.forename: John Piece
authors.initials: JP
authors.lastname: Wise
authors.forename: Theodore R
authors.initials: TR
authors.lastname: Holford
authors.forename: Hong
authors.initials: H
authors.lastname: Xie
authors.forename: Peter
authors.initials: P
authors.lastname: Boyle
authors.forename: Shelia Hoar
authors.initials: SH
authors.lastname: Zahm
authors.forename: Jennifer
authors.initials: J
authors.lastname: Rusiecki
authors.forename: Kaiyong
authors.initials: K
authors.lastname: Zou
authors.forename: Bing
authors.initials: B
authors.lastname: Zhang
authors.forename: Yong
authors.initials: Y
authors.lastname: Zhu
authors.forename: Patricia H
authors.initials: PH
authors.lastname: Owens
authors.forename: Tongzhang
authors.initials: T
authors.lastname: Zheng
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000097:blood / Q000453:epidemiology / Q000209:etiology*; D016022:Case-Control Studies; D003237:Connecticut / Q000453:epidemiology; D019363:Cytochrome P-450 CYP1A1 / Q000235:genetics*; D005260:Female; D006801:Humans; D008875:Middle Aged; D011078:Polychlorinated Biphenyls / Q000097:blood*; D011110:Polymorphism, Genetic / Q000235:genetics*; D018570:Risk Assessment; D044465:White People
chemical_list: D011078:Polychlorinated Biphenyls; D019363:Cytochrome P-450 CYP1A1