However, in hepatocellular carcinoma, TET1 up-regulation promotes the growth of cancer cells through the abnormal enhancer hydroxymethylation of HMGA2 [27], and in lung cancer, it also acts as a cancer-promoting gene to inhibit the aging of lung cancer cells by inhibiting the function of p53 [28]. The gene discussed is HMGA2; the disease is hepatocellular carcinoma.