(A-C) FLT3-ITD AML cell lines MOLM-13, MV4–11, and primary patient sample AML#171 were treated with midostaurin alone or in combination with venetoclax for up to 24 hours. Representative Western blots generated using whole cell lysates are shown. Densitometry measurements, shown below the corresponding blot, were normalized to β-actin and expressed as fold change compared to vehicle control. (D) MOLM-13 and MV4–11 cell lines were treated for 4–24 hours with vehicle control, midostaurin, venetoclax, or in combination. Annexin V-FITC/PI staining and flow cytometry results are shown. ***indicates p<0.001. (E) MOLM-13, MV4–11, and primary patient sample AML#180 were treated with variable concentrations of venetoclax. Representative Western blots are shown. Densitometry measurements, shown below the corresponding blot, were normalized to β-actin and expressed as fold change compared to vehicle control. (F-G) AML cells were treated with venetoclax alone or in combination with the ERK- selective inhibitor SCH772984 for 24 hours. Flow cytometry and Western blot analyses are shown. ***indicates p<0.001. Densitometry measurements, shown below the corresponding blot, were normalized to β-actin and expressed as fold change compared to vehicle control. (H-I) AML cells were treated with midostaurin alone or in combination with the ERK selective inhibitor SCH772984 for 24 hours. Flow cytometry and Western blot analyses are shown. ***indicates p<0.001. Densitometry measurements, shown below the corresponding blot, were normalized to β-actin and expressed as fold change compared to vehicle control.