Regarding the antitumor effect of AGT, we previously suggested that AGT induces apoptosis via caspase activation through cytochrome c release from mitochondria in the monocytic leukemia cell line U937.11 In this study, we further analyzed the antitumor effect of AGT using several hematological tumor cell lines and found that AGT induces apoptosis in K562 and HL60 cells through the expression of Bax and cytochrome c by mitochondrial membrane depolarization but shows no effect on THP-1 cells. This evidence concerns the gene CYCS and monocytic leukemia.