SRC is a signaling mediator in FLT3-ITD⁺ human AML cells. (A) Cells (32D) positive for FLT3-ITD or FLT3-TKD and FLT3-ITD⁺ MV4-11 cells were treated with PKC412 alone or in combination with PKC412 and dasatinib. The proliferation was assessed after 48 hours using the MTT assay. Data are presented as the percentage of DMSO-treated cells and represent values ± SD of triplicates. One representative of at least 3 independent experiments is shown. Statistical analysis was conducted. ***P < .001; **P < .01; *P < .05; and n.s. (no significance), P > .05. (B) MV4-11 cells were starved for 6 hours in serum-free medium in the presence of the indicated concentrations of PKC412 and dasatinib. After treatment, the cells were lysed and subjected to immunoblot analysis with regard to the activation of STAT5 (pSTAT5). To control equal loading, the membrane was stripped and reprobed with a STAT5 and ACTIN Ab. (C) MV4-11 cells expressing FLT3-ITD were incubated in the presence of the indicated amounts of PKC412 and dasatinib for 48 hours. Flow cytometric analysis was performed after staining the cells with annexin V/propidium iodide. The total percentage of annexin V/propidium iodide–positive cells is shown. Data represent the values ± SD of triplicates. One representative of at least 3 independent experiments is shown. Statistical analysis was conducted. ***P < .001; **P < .01; *P < .05; and n.s. (no significance), P > .05. (D) AML patient samples expressing FLT3-ITD or FLT3-TKD were treated with PKC412 and/or dasatinib for 48 hours. Cell viability was determined using the MTT assay. Data are presented as the percentage of DMSO-treated cells and represent values ± SD of triplicates. One representative of at least 3 independent experiments is shown. Statistical analysis was conducted. ***P < .001; **P < .01; *P < .05; and n.s. (no significance), P > .05.