Histone H3k9 And H3k14 Acetylation At The Promoter Of Thelgals9gene Is Associated With Mrna Levels In Cervical Cancer Cells

Galectin-9 levels have been reported to be altered in several cancer types, but the mechanism that regulates the expression of Galectin-9 has not been clarified. Galectin-9 is encoded by theLGALS9gene, which gives rise to eight mRNA variants. The aims of this study were: (a) to identify the mRNA variants ofLGALS9, (b) to characterize CpG methylation and H3K9 and H3K14 histone acetylation at the promoter of theLGALS9gene, and (c) to characterize the relationship between these modifications andLGALS9expression level in cervical cancer cells. All mRNA variants were detected in HaCaT (nontumoural keratinocytes) and SiHa cells, and seven were observed in HeLa cells. The promoter region ofLGALS9contains eight CpG dinucleotides. No hypermethylation pattern related to lowLGALS9expression was identified in tumour cells. Chromatin immunoprecipitation analysis demonstrated higher acetylation of H3K9ac and H3K14ac in HaCaT cells, which was related to higher mRNA levels. The presence of the mRNA variants suggests that alternative splicing may regulate the expression of galectin-9 isoforms. The results of this study suggest that histone acetylation, but not promoter CpG methylation, may be involved in the transcriptional regulation of theLGALS9gene.