title: Repression of the IL-6 gene is associated with hypermethylation.
abstract: The expression of the IL-6 gene is usually tightly controlled and may be induced in specific tissues after treatment with appropriate stimuli. Although much is known about the inducible expression of the IL-6 gene, the molecular mechanisms responsible for its repression in specific tissues or cell types remain poorly defined. To address this question we have studied two human breast carcinoma cell lines, MDA-MB-231, in which the IL-6 gene is expressed, and, MCF-7, in which the IL-6 message is undetectable by Northern blot assay even in the presence of inducers. The expression of the IL-6 message was estimated after treatment with 5-aza-2'deoxycytidine and the methylation state of the IL-6 gene was analyzed. We show herein that treatment of MCF-7 cells with an agent which reduces DNA methylation correlates with IL-6 gene hypomethylation and increases the level of its expression.
mesh_terms: D001374:Azacitidine / Q000031:analogs & derivatives / Q000494:pharmacology; D019175:DNA Methylation; D000077209:Decitabine; D005786:Gene Expression Regulation / Q000235:genetics*; D006801:Humans; D007375:Interleukin-1 / Q000494:pharmacology; D015850:Interleukin-6 / Q000235:genetics*; D011994:Recombinant Proteins / Q000494:pharmacology; D015183:Restriction Mapping; D014407:Tumor Cells, Cultured; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology