DNMT1 and cancer: Contrary to other nucleoside DNMT inhibitors, such as decitabine, 5-fluoro-2′-deoxycytidine, or zebularine [31], NUC013 has been shown to be more effective against cancer cells expressing p53 wild type (WT) than p53 deficient cells [9]; both LoVo and NCI-H460 are p53 WT.