MCL1 and acute myeloid leukemia: Previously, we reported that the Chk1 inhibitor LY2603618 induces DNA damage, decreases Mcl-1 levels (even in the presence of ABT-199), and synergistically induces apoptosis with ABT-199.30 In addition, we have also shown that DNA damage induced by chemotherapeutic agents is enhanced by ABT-199.11,17 While A-1210477 did cause DNA damage, enhanced DNA damage was not observed in the combined treatment, suggesting that DNA damage may not have played a role in the synergistic induction of apoptosis by the two agents in AML cells.