title: Interferon-alpha induces reversible DNA demethylation of the interferon-induced transmembrane protein-3 core promoter in human melanoma cells.
abstract: The interferon (IFN)-α response gene interferon-induced transmembrane protein 3 (IFITM3) has antiproliferative properties in a number of biological systems. In the human melanoma cell line D10, IFITM3 is constitutively expressed and we show that the core promoter is significantly hypomethylated compared to ME15 cells, where IFITM3 is tightly controlled. We demonstrate that treatment of ME15 cells with the demethylating agent 5'-aza-2'-deoxycytidine enhances IFITM3 expression after IFN-α treatment. In a time-course experiment, we show that IFN-α induces demethylation of specific CpG sites of the IFITM3 core promoter 6 h after stimulation and that promoter methylation is precisely re-set to the naïve state 24 h after stimulation. This cyclable modification of methylation requires costimulation with tumor growth factor-beta or expression of the calcium binding protein S100A2, which are known cofactors for enhancement of antiproliferative activity in ME15 cells. Thus, the transcriptional response to IFN-α can be enhanced by promoter demethylation of a subset of inducible genes such as IFITM3. This epigenetic modulation might be crucial to augment the immune response under critical conditions in vivo.
authors.affiliation: Department of Non-Clinical Safety, F. Hoffmann-La Roche Ltd., Basel, Switzerland.
authors.forename: Rachel
authors.initials: R
authors.lastname: Scott
authors.forename: Fredy
authors.initials: F
authors.lastname: Siegrist
authors.forename: Stefan
authors.initials: S
authors.lastname: Foser
authors.forename: Ulrich
authors.initials: U
authors.lastname: Certa
mesh_terms: D001374:Azacitidine / Q000031:analogs & derivatives / Q000494:pharmacology; D054316:Biomarkers, Pharmacological / Q000378:metabolism*; D048708:Cell Growth Processes / Q000187:drug effects; D045744:Cell Line, Tumor; D002630:Chemotactic Factors / Q000235:genetics / Q000378:metabolism; D019175:DNA Methylation / Q000187:drug effects; D015254:DNA Modification Methylases / Q000037:antagonists & inhibitors; D000077209:Decitabine; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D006801:Humans; D016898:Interferon-alpha / Q000494:pharmacology*; D008545:Melanoma / Q000188:drug therapy* / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D011401:Promoter Regions, Genetic / Q000235:genetics; D016601:RNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D009418:S100 Proteins / Q000235:genetics / Q000378:metabolism; D016212:Transforming Growth Factor beta / Q000378:metabolism; D019076:Transgenes / Q000235:genetics
chemical_list: D054316:Biomarkers, Pharmacological; D002630:Chemotactic Factors; C080082:IFITM3 protein, human; D016898:Interferon-alpha; D008565:Membrane Proteins; D016601:RNA-Binding Proteins; D009418:S100 Proteins; C098997:S100A2 protein, human; D016212:Transforming Growth Factor beta; D000077209:Decitabine; D015254:DNA Modification Methylases; D001374:Azacitidine