Other BCL-2 family protein members may also play a role in AML patients refractory/resistant to BCL-2 inhibition, particularly MCL-1, which is an antiapoptotic multidomain protein regulated by distinct cyclin-dependent kinases (CDKs) in both apoptotic and cell-cycling pathways (8, 29–31). The gene discussed is MCL1; the disease is acute myeloid leukemia.