PBX3 and acute myeloid leukemia: CyTOF analyses of three samples of phenotypically characterized AML stem/progenitor cells showed that ziftomenib treatment disparately reduced protein levels of Menin, HOXA9, MEIS1, PBX3, MEF2C, RUNX1, BCL2, CDK6, Ki67, Bcl-xL, MDM2 and BIM (Fig. 1G, H).