PTEN and hepatocellular carcinoma: For example, methyltransferase 3 (METTL3) serves as an oncogene to promote tumorigenesis by enhancing m6A modification and the translation of BCL2 and PTEN in acute myeloid leukemia17, and methyltransferase 14 (METTL14) acts as a suppressor to inhibit tumor metastasis by promoting miR-126 processing in an m6A-dependent manner in hepatocellular carcinoma (HCC)18.