Cell viability assays were performed in cells with non-functional p53 (A673sh, SK-N-MC, STA-ET-2.2, RM-82, PC-3, HEK293, HeLa) or wild-type p53 (TC32, T252, STA-ET-11, CLB-MA, U2OS), and, in disagreement with a previous study of myeloid leukemias [48], we observed high response to NAMPT inhibition in EwS cells with disrupted p53, suggesting that FK866-induced cell death does not depend on functional p53. The gene discussed is NAMPT; the disease is myeloid leukemia.