Since all CML cell lines used in this study had mutant-type p53 and JNJ-165 has been demonstrated to increase MDM2 and p53 levels in leukemia cells with wt p53 [20], we examined whether JNJ-165 affected this pathway in K562 cells. This evidence concerns the gene MDM2 and chronic myelogenous leukemia, BCR-ABL1 positive.