VX-680 preferentially induces apoptosis in Aur-A-high leukemia blasts. (A) Primary leukemic blasts of AML patients were treated with VX-680 (50 nM) for 72 hours. The apoptotic cells were measured by annexin V-FITC staining. The VX-680–induced apoptosis was significantly increased in the Aur-A-high AML cells compared with the normal BMMCs (P < .001) or Aur-A-low AML cells (P < .001). (B) Distribution of the apoptosis in the leukemic blasts induced by VX-680 was indicated according to the FAB type. Normal BMMCs included 12 healthy donors.