Effects of dihydroartemisinin on transplanted prostate cancer in nude mice and expression of VEGF

AIM:To study the inhibitory effects of dihydroartemisinin(DHA)on the growth of transplantation human prostate cancer PC-3 cells in nude mice and the expression level of VEGF and explore the underlying action mechanism.METHODS:Prostate cancer PC-3 cells were transplanted into 20 nude mice to establishthe solid tumor mode.These nude mice were randomly divided into 4 groups with 5 mice in each group:control group,solvent group(dimethyl sulfoxide 1 mL/kg weight),1st experimental group(DHA 100 μmol/kg weight)and 2nd experimental group(DHA 200 μmol/kg weight).The tumor growth inhibition rate was calculated on day 13 after drug administration;Pathomorphism changes of PC-3 cells were observed by light microscope and transmission electron microscope(TEM)after administration of DHA.The positive products of VEGF was tested by immunohistochemical method;Micro-vasvulor density(MVD)was analysed by stereological method.RESULTS:The tumor growth inhibition rates of experimental groups were 63.186% and 69.221%.Apoptotic cells were significantly increased and TEM examination revealedthat the scattered apoptotic bodies were observed in tumor tissues of experimental groups.Immunohistochemical examination revealed that the positive products of VEGF were decreased in experimentalgroups(P0.05);There was no statistically significant difference between 2 experimental groups;There was no statisticallysignificant difference between solvent group and experimental groups,too.MVD was significantly decreased in experimental groups(P0.05);The difference of MVD was not statistical significance between 2 experimental groups;The difference of MVD was not statistical significance between solvent group and experimental groups.CONCLUSION:These results demonstrated that DHA has stronger inhibitory effects on human prostate cancer cell line PC-3 cells in vivo.The action mechanism of DHA might be relatedwith downregulating VEGF.