Fig. 2.

The effects of exogenous FL and bone marrow stroma on FLT3 autophosphorylation and downstream signals in Molm14 cells. Molm14 cells were treated with increasing doses of quizartinib under four different conditions: 1- suspension culture (control); 2- stromal co-culture; 3- suspension culture with exogenous FLT3 ligand (FL) at 2·5 ng/ml; and 4- stromal co-culture with exogenous FL at 2·5 ng/ml. (A) Cells exposed to quizartinib under the four different conditions were lysed and FLT3 autophosphorylation (p-FLT3) was analysed by immunoprecipitation and immunoblotting as described in Methods. (B–D) Whole cell lysates from the four treatment conditions in (A) were probed for phospho- (p-) and total STAT5, AKT and ERK as described in Methods.