Global DNA hypomethylation, rather than reactive oxygen species (ROS), a potential facilitator of cadmium-stimulated K562 cell proliferation.
Cell proliferation plays a critical role in the process of cadmium (Cd) carcinogenesis. Although both induction of reactive oxygen species (ROS) and alteration of DNA methylation are involved in Cd-stimulated cell proliferation, the detailed mechanism of Cd-stimulated cell proliferation remains poorly understood. In this study, K562 cells pre-treated with N-acetylcysteine (NAC) or methionine (Meth) were exposed to Cd to investigate the potential contribution of ROS and global DNA methylation pathways in Cd-induced cell proliferation. The results showed that Cd-stimulated cell proliferation, increased ROS and DNA damage levels, and induced global DNA hypomethylation. The increases of ROS and DNA damage levels were attenuated by pre-treatment with NAC. Cd-stimulated cell proliferation did not appear to be suppressed through eliminating ROS by NAC. However, methionine was shown to prevent Cd-induced global DNA hypomethylation and Cd-stimulated cell proliferation. Our results suggest that global DNA hypomethylation, rather than ROS, is a potential facilitator of Cd-stimulated K562 cell proliferation.
Huang
Dejun
D
Key Laboratory of Arid and Grassland Ecology, School of Life Sciences, Lanzhou University, Lanzhou, PR China.
Zhang
Yingmei
Y
Qi
Yongmei
Y
Chen
Che
C
Ji
Weihong
W
D000111:Acetylcysteine / Q000494:pharmacology; D019256:Cadmium Chloride / Q000633:toxicity*; D002273:Carcinogens / Q000633:toxicity*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D020552:Comet Assay; D004249:DNA Damage; D019175:DNA Methylation / Q000187:drug effects*; D004273:DNA, Neoplasm / Q000737:chemistry / Q000187:drug effects*; D004338:Drug Combinations; D044127:Epigenesis, Genetic / Q000187:drug effects; D016166:Free Radical Scavengers / Q000494:pharmacology; D020868:Gene Silencing / Q000187:drug effects; D006801:Humans; D020014:K562 Cells / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D008715:Methionine / Q000494:pharmacology; D017382:Reactive Oxygen Species / Q000378:metabolism*
D002273:Carcinogens; D004273:DNA, Neoplasm; D004338:Drug Combinations; D016166:Free Radical Scavengers; D017382:Reactive Oxygen Species; D008715:Methionine; D019256:Cadmium Chloride; D000111:Acetylcysteine