As2O3 was reported to induce cell apoptosis by collapsing the mitochondrial membrane potential in acute promyelocytic leukemia (38), enhance the TRAIL-induced apoptosis of glioma cells through the upregulation of DR5 (39), and induce apoptosis by upregulating p53 and activating caspase-3 in human gastric cancer cells (40). Here, CASP3 is linked to acute promyelocytic leukemia.