Meisoindigo is a derivative of indirubin that has anticancer activity. It inhibits the growth of NB4, HL-60, and U937 leukemia and primary acute myeloid leukemia (AML) cells when used at concentrations of 5 and 10 μM. It also halts the cell cycle at the G0/G1 phase and induces apoptosis in leukemia cell lines and primary AML cells, induces myeloid differentiation, and potentiates the effects of cytarabine and idarubicin . Meisoindigo (10 μM) also induces apoptosis, decreases adherence, and decreases the expression of vascular cell adhesion molecule-1 (VCAM-1) in ECV304 human vein endothelial cells. Meisoindigo (50-150 mg/kg per day) decreases spleen size in an HL-60 mouse xenograft model of AML in a dose-dependent manner.
