The Study Of Vitro Effects And The Mechanism Of Thalidomide On Prostate Cancer Cell Line PC-3

Objective: This experiment aimed to evaluate the effect of Thalidomide onproliferation and apoptosis and the expression of hypoxia inducible factor-1α（HIF-1α）、 vascular endothelial growth factor(VEGF)、Bcl-2and Bax proteins inprostate cancer cell line PC-3in vitro，to further investigate possible mechanism of itsrole as angiogenesis inhibitor and activity of anti-tumor on human prostate cancer cellline PC-3in vitro.Methods: l.Human prostate cancer cell line PC-3was incubated in culture medium invitro，using cell counting kit-8assay to detect the growth rate among differentthalidomide concentration groups(25、50、100μg/m1)and different time groups(24、48、72h)． Apoptosis were examined with flow cytometry．2.According to the resultof CCK-8,establishing control and experimental group，extracting total RNA of eachgroup， assessing the integrality and content of RNA， the level of HIF-1α、VEGFmRNA expression was examined by semiquantitative RT-PCR technique in thePC-3cells treated before and after with thalidomide．3. The expression of HIF-1α、VEGF、Bcl-2and Bax protein in PC-3cells treated by Thalidomide was detected byWestern blot.Results:1. CCK-8assay results：Within the concentration of (10-100) μg/ml，thalidomide can obviously inhibit proliferation of PC-3in vitro．The inhibition ratiowas stepping up as the concentration increasing，and the highest inhibition ratio wasin the group with the concentration of l00μg/m1and72h．There was statisticalsignificance of inhibition ratio in different concentration groups of PC-3cells afterbeing treated thalidomide(P<0.05)．The outcome of FCM indicated that after beingtreated with25、50、100μg/m1thalidomide for48h， the apoptotic percentage was16.32％、32.18％、42.68％．seperately,and there was statistically significant differencebetween control group and every treatment group(P <0.05)．2.RT-PCR detection results：There was different depression of the HIF-1α、VEGF mRNA expression indifferent concentration groups of PC-3cells after being treatedthalidomide．Thalidomide obviously repressed the HIF-1α、VEGF mRNA expressionin PC-3at l00μg/m1after treating24h，and there was statistical significance betweenbefore and after treatment(P <0.05)．3. The result of the Western blot showed that aftertreatment with different concentration of thalidomide for24h, the levels of Bcl-2、HIF-1α and VEGF proteins expression were down—regulated in aconcentration—dependent manner，and Bax was up-regulated．Conclusion:1.We comfirmed that thalidomide had the capability of inhibiting theproliferation of PC-3cells in vitro by a dose and time-dependent manner．2.Weconfirmed that thalidomide induced apoptosis in PC-3cells，which may mediated byBcl-2and Bax.expressing the inducement apoptoticis is one of the mechanisms of itsanti-tumor．3.Within a certain drug concentration．thalidomide can inhibit the mRNAand protein expression of HIF-1α and VEGF in PC-3cells．4.Thalidomide may beeffective in HIF-1α and VEGF this two valid targets in PC-3cells, inhibition ofangiogenesis of prostate cancer, leading to inhibition of prostate cancer growth andmetastasis.