Objective: To investigate the induced apoptotic effects and its mechanism of lycopene on human leukemia cell line K562 cells. Method: K562 cells were treated with different concentrations of lycopene (0

20

40

60 μmol·L-1). Cell proliferation in K562 was observed by MTT. Cell apoptosis was inspected by Annexin V/PI double staining method. The expressions of Bcl-2 and Caspase-3 were determined using RT-PCR and Western blot. Result: MTT and Annexin V/PI showed that the rates of proliferation inhibition and apoptosis were positively associated with the concentrations of lycopene (P<0.05). RT-PCR and Western blot indicated that the expression of Bcl-2 gene decreased negatively

but the expression of Caspase-3 gene decreased positively associated with concentration of lycopene (P<0.05). Conclusion: Lycopene could induce the apoptosis of K562 cells

which may be associated with lowering expressions of Bcl-2 and enhancing caspase-3 activity.