CD38 and acute myeloid leukemia: FTY720 also induced cell death in a purified population of CD34+/CD38−/CD123+ cells enriched for leukemic stem and progenitor cells (LSPCs) from FLT3-ITD+ AML patients (Supplementary Figure S6A, S6B), and was more effective than the TKIs AG1296 or CEP701 (Supplementary Figure S6C).