MCL1 and acute myeloid leukemia: The results of O’Reilly et al. show that chemotherapy resistance is mediated by MSC-induced Mcl-1 expression over Bcl-2 and/or Bcl-XL in AML cells, and the inhibition of Mcl-1 restores sensitivity to BH3 mimetics, while the combined inhibition of Bcl-2/Bcl-XL and Mcl-1 restores susceptibility to cytarabine and daunorubicin [110].