5-azacytidine (azacytidine) (81) and 5-aza-2’-deoxycytidine (Decitabine) (80) are two cytosine analogs acting as DNMT inhibitors, approved by the Food and Drug Administration (FDA) as anti-tumor drugs in 2004 and 2006, respectively. The gene discussed is DNMT1; the disease is neoplasm.