Inhibitory effect of apigenin on the growth of human prostate cancer PC-3 cells transplanted tumor in nude mice

Objective To observe the effect of alcgenin on the growth of human prostate cancer PC-3 cells transplanted tumor in nude mice.Methods Human prostate cancer PC-3 cells cultured in vitro were subcutaneously inoculated into nude mice to establish transplanted tumor model.All tumor-bearing mice were randomly divided into 4 groups:control group ( DMSO and normal saline,0.2 ml/day),low dose apigenin group ( 1 2.5 mg/kg per day),middle dose apigenin group (25 mg/kg per day ),high dose apigenin group (50 mg/kg per day).There were 6 nude mice in each group,and daily intraperitoneal injection was done for 28 days.The transplanted tumor growth curve was drawn according to transplanted tumor volume,and inhibition ratio was calculated according to the final tumor weight.The ultrastructural changes of tumor cells were observed under a transmission electron microscope (TEM).Results According to the volume change of different groups,apigenin showed significantly inhibitory effect on the growth of transplanted tumor in middle and high dose apigenin groups as comapred with control group and low dose apigenin group (P ＜0.05).There was no significant different in inhibitory effect on the growth of transplanted tumor between control and low dose apigenin groups ( P ＞ 0.05 ).The final tumor weight in middle dose apigenin group was ( 1.44 ±0.50) g and inhibitory rate was 46.7％,and those in high dose apigenin group was (0.46 ±0.17 ) g and 83.0％ respectively,which was significantly different from those in control group [ (2.70 ±0.52) g and 0.0％ ] and low dose apigenin group [ (2.68 ±0.41 ) g and 0.7％ ] ( P ＜0.05).However,there was no statistically significant difference between control and low dose apigenin group ( P ＞0.05 ).TEM observation showed morphological changes of apoptosis and oncosis of tumor cells in the middle and high dose apigenin groups,while no such changes were seen in control and low dose apigenin groups:Conclusion The middle and high doses of apigenin has the inhibitory effect on the growth of transplanted tumor of prostate cancer PC-3 cells in nude mice probably through the mechanisms of apoptosis and oncosis. Key words: Apigenin;  Prostate cancer;  Transplanted tumor