LAUSR

PURPOSE To investigate the role and prognostic value of mH2A1 in the progression of hepatocellular carcinoma (HCC). METHODS Basing on the Cancer Genome Atlas-Liver Hepatocellular Carcinoma (TCGA-LIHC) and GEO datasets, the gene expression of mH2A1 and relative clinical characteristics were analyzed to assess the prognostic significant of mH2A1 in HCC. The protein expression of mH2A1 was measured by immunohistochemistry. Stable cell lines and nude mice model were used to investigate the role of mH2A1 in the progression of HCC. RESULTS In this study, using TCGA-LIHC data and HCC tissue microarray, we found that expression of mH2A1 was higher in tumor tissues than in adjacent normal tissues. These results were validated using the GEO database. Patients with high levels of mH2A1 were predicted to have larger tumor size and more advanced tumor stage and grade. Multivariate analysis revealed that increased mH2A1 expression was an independent prognostic risk factor of shorter overall survival (OS). Experimental results showed that elevated mH2A1 expression promoted the progression of HCC while reduced mH2A1 expression lead to opposite effects in vitro and in vivo. mH2A1 promoted the progression of HCC by regulating cell cycle via AKT. Dysregulated expression of mH2A1 was associated with its DNA methylation status. Two CpG sites (cg01466741 and cg02614129) were negatively correlated with mH2A1 expression. Notably, high methylation of both CpG sites was associated with better OS. CONCLUSION Based on the above results, we concluded that upregulated mH2A1 in HCC promoted tumor progression and could serve as an unfavorable prognostic indicator.