The FLT3-ITD/D835N dual mutant restores the SU5614-resistant phenotype in Ba/F3 cells. (A) The Ba/F3 FLT3-ITD–, FLT3-D835N–, and FLT3-ITD/D835N–expressing cells were seeded at a density of 4 × 10⁴ cells/mL in the absence or presence of different concentrations of SU5614, and viable cells were counted after 72 hours by trypan blue exclusion. Values represent means and standard deviations from 3 independent experiments. (B-C) MIG FLT3-ITD (GFP⁺)– and MIY FLT3-ITD/D835N (YFP⁺)–expressing Ba/F3 cells were mixed in a ratio of 10:1, and the percentage of GFP⁺ and YFP⁺ cells was measured every 3 to 4 days for a time period of 2 weeks by FACS analysis in the presence (B) or absence (C) of 0.2 μM SU5614.