Dexamethasone enhances the antileukemic efficacy of quizartinib in FLT3-mutated AML patient samples ex vivo and AML mouse models in vivo. (A) Representative microscopy images of patient 791 cells treated with DMSO, 100 nM quizartinib, 50 µM dexamethasone, or the combination for 48 hours and corresponding FACS images of cells labeled with APC-Annexin-V and 7-AAD. (B) Quantification of FACS analysis of cell death in 5 FLT3 mutant and 4 wild-type AML patient (Pt) cells treated with the indicated drugs and concentration for 48 hours. (C) In vivo bioluminescence imaging of NSG mice orthotopically xenografted with MOLM13-Luc cells and treated with the indicated drugs or vehicle. Images were obtained at the indicated time points. (D) Bioluminescence quantification of C. Tumor weight (E) and tumor volume (F) of NSG mice subcutaneously xenografted with MOLM13 cells and treated with the indicated drugs for 20 days after 10 days of tumor engraftment.