Cytotoxic and apoptotic effects of prenylflavonoid artonin B in human acute lymphoblastic leukemia cells.

AIM: To investigate the anticancer effects and molecular mechanism of artonin B on the human acute lymphoblastic leukemia CCRF-CEM cells compared with other prenylflavonoid compounds.

METHODS: The effects of four prenylflavonoids on the growth of CCRF-CEM and HaCa cells were studied by 3-(4,5)-2,5-diphenyl-tetrazolium bromide (MTT) assay. Apoptosis were detected through Hoechst 33258 staining. The effect of artonin B on the cell cycle of CCRF-CEM cells were studied by propidium iodide method. The change in mitochondrial membrane potential was detected by rohdamine 123 staining. The cytochrome c release and caspase 3 activity were checked by immunoassay kits, respectively. The expression of Bcl-2 family proteins was detected by Western blot.

RESULTS: Our data revealed that artonin B strongly induced human CCRF-CEM leukemia cell death in a dose- and time-dependent manner by MTT assay, but not on normal epithelia cells (HaCa cells). Artonin B-induced cell death was considered to be apoptotic by observing the typical apoptotic morphological change by Hoechst 33258 staining. The induction of human CCRF-CEM leukemia cancer cell death was caused by an induction of apoptosis through mitochondrial membrane potential change, cytochrome c release, sub-G1 proportion increase, downregulation of Bcl-2 expression, upregulation of Bax and Bak expression and activation of caspase 3 pathways.

CONCLUSION: These results clearly demonstrated that artonin B is able to inhibit proliferation by induction of hypoploid cells and cell apoptosis. Moreover, the anticancer effects of artonin B were related to mitochondrial pathway and caspase 3 activation in human CCRF-CEM leukemia cells.