MCL1 and chronic myelogenous leukemia, BCR-ABL1 positive: For example, in addition to triggering aberrant cell proliferation, a number of anti-apoptotic Bcl-2 proteins such as Mcl-1 and Bcl-xL are regulated by Bcr-Abl tyrosine kinase signaling, which can confer apoptosis resistance to CML cells [18, 19].