The functional and mechanistic relatedness of EZH2 and menin in hepatocellular carcinoma.

Abstract

BACKGROUND & AIMS:

The alterations of histone modification may serve as a promising diagnostic biomarker of hepatocellular carcinoma (HCC), but the clinical and mechanistic relatedness of the histone H3 lysine 27 and 4 trimethylation (H3K27me3 and H3K4me3) in HCC remains poorly understood. Here we propose that the combination of H3K27me3 and H3K4me3 is a more precise predictive/prognostic value for outcome of HCC patients.

METHODS:

We used chromatin immunoprecipitation (ChIP) assays and a ChIP-on-chip screen to analyse HCC.

RESULTS:

We found that the EZH2 occupancy coincides with the H3K27me3 at promoters and directly silences the transcription of target genes in HCC. The H3K27me3-related gene network of EZH2 contains well-established genes, such as CDKN2A, as well as previously unappreciated genes, including FOXO3, E2F1, and NOTCH2, among others. We further observed independently increasing profiles of H3K27me3 and H3K4me3 at the promoters of certain target genes in HCC specimens. Importantly, Kaplan-Meier analysis reveals that 3-year overall and tumour-free survival rates are dramatically reduced in patients that simultaneously express EZH2 and menin, compared to rates in the EZH2 or menin under expressing patients. Furthermore, an inhibitor of H3K27me3 alone, or in combination with an H3K4me3 inhibitor, effectively blocked the aggressive phenotype of HCC cells.

CONCLUSIONS:

Our results indicate that a combined analysis of both H3K27me3 and H3K4me3 may serve as powerful diagnostic biomarkers of HCC, and targeting both might benefit anti-HCC therapy.

• Authors: Shu-Bin Gao, Bin Xu, Li-Hong Ding, Qi-Lin Zheng, Li Zhang, Qi-Fan Zheng, Shan-Hua Li, Zi-Jie Feng, Jie Wei, Zhen-Yu Yin, Xianxin Hua, Guang-Hui Jin
• Journal: Journal of hepatology (J Hepatol) Vol. 61 Issue 4 Pg. 832-9 (Oct 2014) ISSN: 1600-0641 [Electronic] Netherlands
• PMID: 24845612 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2014 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

Chemical References

• Histones
• MEN1 protein, human
• Proto-Oncogene Proteins
• EZH2 protein, human
• Enhancer of Zeste Homolog 2 Protein
• Polycomb Repressive Complex 2

Topics

• Carcinoma, Hepatocellular (genetics, metabolism, pathology)
• Enhancer of Zeste Homolog 2 Protein
• Female
• Gene Expression Regulation, Neoplastic
• Genes, Tumor Suppressor
• Histones (analysis, metabolism)
• Humans
• Liver Neoplasms (genetics, metabolism, pathology)
• Male
• Methylation
• Middle Aged
• Neoplasm Staging
• Polycomb Repressive Complex 2 (genetics)
• Prognosis
• Protein Processing, Post-Translational (genetics)
• Proto-Oncogene Proteins (genetics)