Treatment with FHD-286 significantly depleted c-Myc and PU.1 expression in bulk AML cells and phenotypically defined AML stem cells with MLL1r or mtNPM1. (A) MOLM13 and PD mtNPM1 expressing AML cells were treated with 100 nM of FHD-286 for 48 hours. Total proteome profiling was conducted by mass spectrometry analysis. The heat map shows selected overlapping depleted and induced protein expressions with a fold change >1.25 and a P value <.05. (B) Log2 fold decline in protein expressions in FHD-286–treated MOLM13 and PD mtNPM1-expressing AML cells compared with REACTOME_SIGNAL_TRANSDUCTION and REACTOME_RNA_POLII_TRANSCRIPTION pathways. (C) PD MLL1r and mtNPM1 AML cells were treated with 100 nM of FHD-286 for 48 hours. CyTOF analyses were conducted using cocktails of rare metal element–tagged antibodies. The heat map shows the fold change (FHD-286 treated over control) of depleted and induced proteins in phenotypically defined AML stem/progenitor cells (CLEC12A hi, CD123 hi, CD99 hi, CD33 hi, and CD11b low). (D) Percentage of stem cell frequency of control and FHD-286–treated PD MLL1r and mtNPM1 expressing AML cells.