Pre-treatment with pan-caspase inhibitor Q-VD-OPh significantly delayed and partially prevented the increase in proportion of Annexin V+ cells (Fig. 2d) as well as completely abolished the cleavage of PARP and CASPASE 3 upon CCI-006 treatment (Fig. 2e), providing evidence that CCI-006 affected MLL-r leukemia cell viability by inducing caspase-mediated apoptosis. This evidence concerns the gene CASP3 and leukemia.