title: Persistent organic pollutants and promoter hypermethylation of the O(6)-methylguanine-DNA methyltransferase gene.
abstract: Promoter hypermethylation of the O(6)-methylguanine-DNA methyltransferase (MGMT) DNA repair gene is important during carcinogenesis. We explored whether organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs), were associated with hypermethylation of the MGMT gene promoter in peripheral leukocytes among 368 Koreans without cancer. Hypermethylation decreased as OCPs increased (Ptrend = 0.02), while PCB concentrations showed an inverted U-shaped association (Pquadratic < 0.01). The prevalence of MGMT promoter hypermethylation was highest within the 2nd quintile of the PCB summary score (28.4%), while it was only 2.7% in the upper 10% score. Chronic exposure to these chemicals may affect methylation of the MGMT promoter, with possibly non-monotonic dose response relationships.
authors.affiliation: Colorectal Cancer Center, Kyunpook National University Medical Center, School of Medicine, Kyunpook National University , Daegu , Korea .
authors.forename: Soo Yeun
authors.initials: SY
authors.lastname: Park
authors.forename: Ki-Su
authors.initials: KS
authors.lastname: Kim
authors.forename: Yu-Mi
authors.initials: YM
authors.lastname: Lee
authors.forename: Mi-Jin
authors.initials: MJ
authors.lastname: Kim
authors.forename: David R
authors.initials: DR
authors.lastname: Jacobs
authors.forename: Miquel
authors.initials: M
authors.lastname: Porta
authors.forename: Dong-Sun
authors.initials: DS
authors.lastname: Kim
authors.forename: Duk-Hee
authors.initials: DH
authors.lastname: Lee
mesh_terms: D016022:Case-Control Studies; D019175:DNA Methylation; D004785:Environmental Pollutants / Q000097:blood; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D006843:Hydrocarbons, Chlorinated / Q000097:blood*; D016015:Logistic Models; D008875:Middle Aged; D019853:O(6)-Methylguanine-DNA Methyltransferase / Q000235:genetics; D010575:Pesticides / Q000097:blood*; D011078:Polychlorinated Biphenyls / Q000097:blood*; D016133:Polymerase Chain Reaction; D011401:Promoter Regions, Genetic / Q000235:genetics; D011795:Surveys and Questionnaires
chemical_list: D004785:Environmental Pollutants; D006843:Hydrocarbons, Chlorinated; D010575:Pesticides; D011078:Polychlorinated Biphenyls; D019853:O(6)-Methylguanine-DNA Methyltransferase
keywords: MGMT; Methylation; organochlorine pesticides; persistent organic pollutants; polychlorinated biphenyls