METTL3 and hepatocellular carcinoma: Overall, about thirteen m6A regulators are reported to be closely related to HCC prognosis and have a potential for use as prognosis biomarkers, including four methyltransferases (KIAA1429, WTAP, METTL14 and METTL3), four demethylases (ALKBH5, FTO, RALYL and ZC3H13), and five reading proteins (IGF2BP1, YTHDF1-3 and LRPPRC (Table 3).