Transfection of Ik6 in an imatinib-sensitive Ik6-negative Ph⁺ ALL cell line. Induction of DNA synthesis (A) and colony growth (B) in pcDNA-Ik6 SUP-B15 transfected cells. Mean value of colony growth from control cells and after incubation with imatinib, nilotinib, and dasatinib. (C) Apoptotic rates evaluated by FACS for the detection of annexin V–positive cells in pcDNA-Ik6 SUP-B15–transfected cells and in cells transfected with the empty vector (pEGFP) after incubation with imatinib.