SPHK1 and chronic myelogenous leukemia, BCR-ABL1 positive: In CML, which is caused by potent oncogenic protein Bcr-Abl, the activity of sphingosine kinase-1 (SphK1) is elevated by Bcr-Abl to increase expression of antiapoptotic protein Mcl-1 [151] and Bcr-Abl inhibitor imatinib-induced apoptosis through inhibiting SphK1 [152].