TTT-3002 inhibits FLT3 signaling and reduces cell viability in primary FLT3/ITD AML patient blasts. (A) Inhibition of pFLT3 in leukemic cells from FLT3/ITD AML patients treated ex vivo with TTT-3002. Fraction of pFLT3/FLT3 relative to DMSO control is indicated below each blot; representative example of FLT3/ITD AML. (B) Quantitation of (A), representing results from 3 unique patient samples ± SD; ***P < .001. (C) Percentage of Annexin V-positive cells of leukemic BM from FLT3/ITD AML patients or BM from healthy donors at 48 hours following treatment with increasing concentrations of TTT-3002. Normal BM (n = 2), FLT3/ITD AML (n = 4); error bars represent average of triplicate samples ± SD; *P < .05; **P < .01; ***P < .001; ns, not significant. (D) Colony proportions of burst-forming unit erythroid (BFU-E), CFU-granulocyte-macrophage, CFU-granulocyte, and CFU-macrophage colonies from BM mononuclear cells of healthy donors treated with increasing concentrations of TTT-3002 (representative example shown). Error bars represent average ± SD. (E) Total colony counts from BM mononuclear cells from healthy donors treated with increasing concentrations of TTT-3002 (representative example shown). Error bars represent average ± SD. (F) Total colony counts from 1 × 104 CD34+ stem/progenitor cells from healthy donors treated with increasing concentrations of TTT-3002 (representative example shown). Error bars indicate average ± SD.