METTL3 and hepatocellular carcinoma: To explore m6A methylation change in the livers of HCC patients, 17 samples of tissues (Tumor and normal tissues) were collected; the total RNA was extracted by TRIzol, and qPCR was used to detect mRNA levels of the m6A methylation complex, including WTAP, METTL3, METTL14, FTO, ALKBH, YTHDF1, YTHDF2 and YTHDF3.