ABL1 and chronic myelogenous leukemia, BCR-ABL1 positive: Augmentation of ceramide levels using the glucosylceramide synthase inhibitor D-threo-l-phenyl-2-decanoylamino-3-morpholino-1-propanol (PDMP), enhanced apoptosis and resensitised T315I mutant CML cells to both Imatinib and Nilotinib59 suggesting co-targeting BCR-ABL with sphingolipid modulating agents may be a novel strategy to further enhance the efficacy of TKI treatment.