title: Inhibition of the extracellular signal-regulated kinase/mitogen-activated protein kinase pathway decreases DNA methylation in colon cancer cells.
abstract: The extracellular signal-regulated kinase/mitogen-activated protein kinase (ERK-MAPK) pathway is a critical intermediary for cell proliferation, differentiation, and survival. In the human colon cancer cell line SW1116, treatment with the DNA methyltransferase 1 (DNMT1) inhibitor 5-aza-2'-deoxycytidine (5-aza-dC) or the ERK-MAPK inhibitors PD98059 or rottlerin, or transient transfection with the MAP/ERK kinase (MEK)1/2 small interfering RNA down-regulates DNMT1 and proliferating cell nuclear antigen levels. In this report, we found that drug treatment or small interfering RNA transfection of SW1116 cells induced promoter demethylation of the p16(INK4A) and p21(WAF1) genes, which up-regulated their mRNA and protein expression levels. Flow cytometry revealed that rottlerin treatment induced cell cycle arrest at phase G(1) (p < 0.05). Thus, the ERK-MAPK inhibitor treatment or siRNA-mediated knockdown of ERK-MAPK decreases DNA methylation via down-regulating DNMT1 expression and other unknown mediator(s) in SW1116 colon cancer cells.
authors.affiliation: Shanghai Jiaotong University School of Medicine, Renji Hospital, Shanghai Institute of Digestive Disease, Shanghai 200001, China.
authors.forename: Rong
authors.initials: R
authors.lastname: Lu
authors.forename: Xia
authors.initials: X
authors.lastname: Wang
authors.forename: Zhao-Fei
authors.initials: ZF
authors.lastname: Chen
authors.forename: Dan-Feng
authors.initials: DF
authors.lastname: Sun
authors.forename: Xiao-Qing
authors.initials: XQ
authors.lastname: Tian
authors.forename: Jing-Yuan
authors.initials: JY
authors.lastname: Fang
mesh_terms: D000098:Acetophenones / Q000494:pharmacology; D001483:Base Sequence; D001578:Benzopyrans / Q000494:pharmacology; D045744:Cell Line, Tumor; D003110:Colonic Neoplasms / Q000378:metabolism*; D050759:Cyclin-Dependent Kinase Inhibitor p21 / Q000378:metabolism; D000076123:DNA (Cytosine-5-)-Methyltransferase 1; D004248:DNA (Cytosine-5-)-Methyltransferases / Q000037:antagonists & inhibitors; D019175:DNA Methylation; D017931:DNA Primers / Q000737:chemistry; D004791:Enzyme Inhibitors / Q000494:pharmacology; D048049:Extracellular Signal-Regulated MAP Kinases / Q000037:antagonists & inhibitors*; D005419:Flavonoids / Q000494:pharmacology; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D020935:MAP Kinase Signaling System; D008969:Molecular Sequence Data
chemical_list: D000098:Acetophenones; D001578:Benzopyrans; C493956:CDKN1A protein, human; D050759:Cyclin-Dependent Kinase Inhibitor p21; D017931:DNA Primers; D004791:Enzyme Inhibitors; D005419:Flavonoids; C085746:rottlerin; D000076123:DNA (Cytosine-5-)-Methyltransferase 1; D004248:DNA (Cytosine-5-)-Methyltransferases; C000619380:DNMT1 protein, human; D048049:Extracellular Signal-Regulated MAP Kinases; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one