Acute myeloid leukemia (AML) is a highly malignant hematopoietic tumor.The use of all-trans retinoic acid (ATRA) and arsenic trioxide,which began from China,has resulted in revolution of the acute promyelocytic leukemia (APL) that appears curable in more than 70％ of patients[1].However,the treatment regimen for nonAPL AML particularly in older patients has progressed little in the past two decades.Intensive efforts have been made toward the development of novel target agents,which are based on newfound pathophysiological events crucial for cancers.