Inhibition of wild-type FLT3 by SU5614 reverts the antiapoptotic effect of FL in serum-starved OCI-AML5 cells.
(A) After a 16-hour starvation period in RPMI 1640 with 0.25% FBS, cells were washed twice and seeded at a density of 2.0 × 105 cells/mL in RPMI 1640 with 0% FBS and with 100 ng/mL FL and 5 μM SU5614 as indicated. Viable cells were counted for 4 days by trypan blue exclusion. Values represent means and SDs from 3 independent experiments. (B) Cells were seeded at a density of 1.0 × 105/mL in the absence or presence of 10 μM SU5614. Viable cells were counted for 3 days by trypan blue exclusion. Mean values and SEs were calculated from 3 independent experiments. (C) OCI-AML5 cells were starved in RPMI 1640 with 0.3% FBS 16 hours prior to incubation with the indicated concentrations of SU5614. After 1 hour of inhibitor incubation, cells were stimulated with FL for 5 minutes and lysed. Protein lysates were immunoprecipitated (IP) with FLT3 antibody and precipitates were analyzed by Western blot.
