METTL3 and hepatocellular carcinoma: Nishizawa et al. (2018) pointed out that YTHDF1 is significantly overexpressed in colorectal cancer samples relative to adjacent normal specimens, and closely correlated to pathological stage. Taketo et al. (2018) revealed that the low expression level of METTL3 makes pancreatic cancer cells sensitive to radiotherapy and antitumor treatment. Emerging studies have demonstrated that dysregulated m6A modification level and its modulators are significantly linked to HCC tumorigenesis and development (Ma et al., 2017; Yang et al., 2017; Chen et al., 2018; Rong et al., 2019; Zhong et al., 2019).