While only decitabine sensitivity has been linked to KRAS status so far (Stewart et al, 2015), there is increasing evidence that both azacytidine and decitabine induce reactive oxygen species which cause DNA damage and finally apoptosis in cancer cells (Gao et al, 2008; Shin et al, 2012; Fandy et al, 2014). This evidence concerns the gene KRAS and cancer.