MCL1 and acute myeloid leukemia: Profiling of various key apoptosis-regulatory proteins in the intrinsic and extrinsic pathways and the subsequent comparison of those ouabain target proteins between LSCs and LPCs suggested that Mcl-1 and c-Myc may be important regulators of ouabain sensitivity in AML cells that plausibly caused the distinct apoptotic responses between LSCs and LPCs (Fig. 8), although we did not exclude the possible roles of c-FLIP in both isoforms herein.