Loss of KDM6B confers resistance to lipotoxicity through epigenetic downregulation of G0S2 expression in NASH-related HCC

ABSTRACT: Background& Aims: The incidence of nonhepatitis B and nonhepatitis C viral (NBNC)- HCC has been rising in recent years due to the increase in NAFLD and NASH　worldwide with fibrosis. However, the molecular mechanisms underlying the progression of these HCC are not fully understood. Here we observed that KDM6B, an H3K27 demethylase, was commonly downregulated in human NBNC-HCC and mouse NASH-related HCC by microarray analysis. The study aims to elucidate the molecular mechanism of KDM6B downregulation in NBNC-HCC including NASH-related HCC. Approach & Results: By immunohistochemistry, KDM6B expression was decreased in 28.7% of human HCC tissues, most of which were NBNC-HCC type. The low KDM6B expression group was accompanied by NASH in the adjacent liver. The KDM6B knockout (KO) HCC cells altered pathways of lipid metabolism by microarray and GSEA analysis. The KDM6B-KO cells significantly decreased lipid accumulation and cell reduction rates. Expression of two lipid-metabolism-related genes, G0S2 and ACSL1, were suppressed in the KDM6B-KO cells and the histone H3K27 trimethylation levels at the promoter regions were decreased when compared to the wild-type cells. Knockdown of G0S2 but not ACSL1 expression showed resistance to lipotoxicity in HCC cells. Moreover, inhibition of ATGL, a downstream target of G0S2, caused a decrease in lipid accumulation and cell proliferation. Conclusions: KDM6B regulates G0S2 expression via histone demethylation of its promoter region. Decreased KDM6B-dependent G0S2 expression through the histone modification pathway causes resistance to lipotoxicity, which may be involved in the carcinogenic mechanism of NASH-related HCC among NBNC-HCC.

ORGANISM(S): Homo sapiens

PROVIDER: GSE211848 | GEO | 2023/10/11

REPOSITORIES: GEO