Prostaglandin E₂ increases fibroblast gene-specific and global DNA methylation via increased DNA methyltransferase expression.
Although alterations in DNA methylation patterns have been associated with specific diseases and environmental exposures, the mediators and signaling pathways that direct these changes remain understudied. The bioactive lipid mediator prostaglandin E(2) (PGE(2)) has been shown to exert a myriad of effects on cell survival, proliferation, and differentiation. Here, we report that PGE(2) also signals to increase global DNA methylation and DNA methylation machinery in fibroblasts. HumanMethylation27 BeadChip array analysis of primary fetal (IMR-90) and adult lung fibroblasts identified multiple genes that were hypermethylated in response to PGE(2). PGE(2), compared with nontreated controls, increased expression and activity (EC(50)∼10(7) M) of one specific isoform of DNA methyltransferase, DNMT3a. Silencing of DNMT3a negated the ability of PGE(2) to increase DNMT activity. The increase in DNMT3a expression was mediated by PGE(2) signaling via its E prostanoid 2 receptor and the second messenger cAMP. PGE(2), compared with the untreated control, increased the expression and activity of Sp1 and Sp3 (EC(50)∼3×10(7) M), transcription factors known to increase DNMT3a expression, and inhibition of these transcription factors abrogated the PGE(2) increase of DNMT3a expression. These findings were specific to fibroblasts, as PGE(2) decreased DNMT1 and DNMT3a expression in RAW macrophages. Taken together, these findings establish that DNA methylation is regulated by a ubiquitous bioactive endogenous mediator. Given that PGE(2) biosynthesis is modulated by environmental toxins, various disease states, and commonly used pharmacological agents, these findings uncover a novel mechanism by which alterations in DNA methylation patterns may arise in association with disease and certain environmental exposures.
Division of Pulmonary and Critical Care Medicine, University of Michigan Medical School, Ann Arbor, Michigan, USA. stehuang@umich.edu.
Steven K
SK
Huang
Anne M
AM
Scruggs
Jake
J
Donaghy
Richard C
RC
McEachin
Aaron S
AS
Fisher
Bruce C
BC
Richardson
Marc
M
Peters-Golden
D000818:Animals; D002460:Cell Line; D020552:Comet Assay; D000242:Cyclic AMP / Q000378:metabolism; D004248:DNA (Cytosine-5-)-Methyltransferases / Q000378:metabolism*; D019175:DNA Methylation; D000090205:DNA Methyltransferase 3A; D015232:Dinoprostone / Q000502:physiology*; D005347:Fibroblasts / Q000378:metabolism; D015971:Gene Expression Regulation, Enzymologic / Q000502:physiology; D006801:Humans; D051379:Mice; D060888:Real-Time Polymerase Chain Reaction; D015398:Signal Transduction; D016329:Sp1 Transcription Factor / Q000235:genetics; D051705:Sp3 Transcription Factor / Q000235:genetics
C000717967:DNMT3A protein, human; C000715535:Dnmt3a protein, mouse; D016329:Sp1 Transcription Factor; D051705:Sp3 Transcription Factor; D000242:Cyclic AMP; D004248:DNA (Cytosine-5-)-Methyltransferases; D000090205:DNA Methyltransferase 3A; D015232:Dinoprostone