Until now, epidrugs including DNA methyltransferase (DNMT) inhibitor guadecitabine and histone deacetylase (HDAC) inhibitors vorinostat and belinostat were experimentally tested for treating HCC, but they were limited to the clinical trials and did not enter beyond phase II trials, owing to the safety problem.7 The gene discussed is DNMT1; the disease is hepatocellular carcinoma.