DNMT1 and hepatocellular carcinoma: TERT expression was then manipulated in cancerous cells derived from hepatocellular carcinoma (HCC), and DNMT3B, but not DNMT3A nor DNMT1, was observed to be down- and up-regulated by TERT depletion and over-expression, respectively, which suggested the presence of a causal association between TERT and DNMT3B expression [37].