MCL1 and acute myeloid leukemia: In particular, we were keen to test responsiveness to recently developed BH3 mimetics (drugs that mimic BH3-only proteins) and to agents reported to downregulate MCL-1, such as CDK7/9 inhibitors [16, 17] and the proteasome inhibitor bortezomib [18], which is being trialled clinically for AML [19].