998 Review Article Research progress on DNA methylation in hepatocellular carcinoma Yongchang Zheng*, Xin Wang*, Feihu Xie, Zhaoqi Gu, Li He, Shunda Du, Haitao Zhao, Yiyao Xu, Xin Lu, Yilei Mao, Xinting Sang, Haifeng Xu, Tianyi Chi Department of Liver Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing 100730, China Contributions: (I) Conception and design: Y Zheng, H Xu, T Chi; (II) Administrative support: X Sang, Z Gu, L He, S Du, H Zhao, Y Xu, X Lu, Y Mao; (III) Provision of study materials or patients: Y Zheng, X Wang; (IV) Collection and assembly of data: Y Zheng, X Wang; (V) Data analysis and interpretation: X Wang, F Xie; (VI) Manuscript writing: All authors; (VII) Final approval of manuscript: All authors. *These authors contributed equally to this work. Correspondence to: Haifeng Xu, MD. Department of Liver Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing 100730, China. Email:
[email protected]; Tianyi Chi, MD. Department of Liver Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing 100730, China. Email:
[email protected]. Abstract: Hepatocellular carcinoma (HCC) is a common malignant tumor with high incidence and morbidity worldwide. The pathogenesis and progression of HCC are closely related to abnormal epigenetic regulation of hepatocytes. DNA methylation is an important regulatory mechanism in epigenetics which has been deeply and widely investigated. Along with the development of high-throughput sequencing techniques, including high-throughput gene chip analysis and next generation sequencing, great progress was achieved toward the understanding of the epigenetic regulation of HCC.