1q21 amplification correlates with increased MCL-1i sensitivity. (A) Differences in specific apoptosis of patients with wild-type (WT) 1q21 (n = 32) or amplification of 1q21 (n = 12), after treatment with MCL-1i for 24 hours. (B) Differences in specific apoptosis of patients with WT and amplified 1q21 after treatment with BCL-2i (left) or BCL-XLi (right) and their combinations with MCL-1i (all inhibitors, 100 nM). ns, nonsignificant.