Biomarkers, Early Online: 1–7
 

Persistent organic pollutants and promoter hypermethylation of the O6-methylguanine-DNA methyltransferase gene

Soo Yeun Park1, Ki-Su Kim2#, Yu-Mi Lee2#, Mi-Jin Kim3, David R. Jacobs Jr4, Miquel Porta5, Dong-Sun Kim3,6, and Duk-Hee Lee2,6
 

Abstract

Promoter hypermethylation of the O6-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 (Ptrend¼0.02), while PCB concentrations
showed an inverted U-shaped association (Pquadratic50.01). 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.