RNA干扰下调人滋养层细胞表面抗原-2基因表达对前列腺细胞侵袭及尿激酶纤溶酶原激活物蛋白的影响

Effects of trophoblast cell-surface antigens 2 gene downregulated by RNA interference on invasion of human prostate carcinoma cells and urokinase-type plasminogen activator protein

目的 观察人滋养层细胞表面抗原-2（Trop-2）基因对人前列腺细胞侵袭的影响,并探讨其分子机制.方法 采用TROP-2基因小于扰RNA（siRNA）转染处理人前列腺PC-3细胞后,分别采用实时荧光定量聚合酶链反应（FQ-PCR）和Western blot检测TROP-2基因mRNA和蛋白水平;采用Transwell小室法试验检测癌细胞侵袭能力;采用Western blot法检测癌细胞尿激酶纤溶酶原激活物（uPA）蛋白变化.结果 siRNA转染组细胞TROP-2基因mRNA和蛋白水平明显下调,且呈浓度依赖性（P＜0.01）.siRNA转染组穿过滤膜的细胞数明显下降,且呈浓度依赖性（P＜0.01）.Transwell小室试验结果显示,Con-A、Con-B、siRNA（5nmol/L）、siRNA（10 nmol/L）、siRNA（20 nmol/L）组穿膜细胞数分别为（128.16 ±3.89）、（127.58 ±3.56）、（102.56 ±3.28）、（76.38 ±3.25）和（39.89±3.18）个.Western blot结果显示,TROP-2 siRNA转染组uPA蛋白表达明显下调,且与浓度相关.结论 TROP-2基因在人前列腺癌细胞侵袭中发挥重要的作用,采用siRNA转染可抑制前列腺细胞侵袭,下调uPA表达,是其重要机制之一.

Objective To explore the effects and mechanism of trophoblast cell-surface antigens 2 （TROP-2） on invasion of human prostate cancer cells.Methods After human prostate cancer PC-3 cell line was transfected with TROP-2 small interfering RNA （siRNA）,the mRNA and protein levels of TROP-2 were determined by using real-time reverse transcriptase-polymerase chain reaction （RT-qPCR） and Western blotting respectively.The invasion ability was evaluated by Transwell.The urokinase-type plasminogen activator （uPA） protein of cancer cells was examined by Western blotting.Results The mRNA and protein expression levels of TROP-2 were greatly inhibited in PC-3 cancer cells transfected with TROP-2 siRNA.The results of the Transwell assay showed that the number of cells penetrating the membrane in Con-A,Con-B,and siRNA groups （5,10 and 20 nmoL/L） was 128.16 ± 3.89,127.58 ± 3.56,102.56 ± 3.28,76.38 ± 3.25,and 39.89 ±3.18,respectively （P ＜0.05）.The results from Western blotting assay showed that the uPA protein in siRNA groups was reduced significantly.Conclusion TROP-2 siRNA inhibit the invasion of prostate cancer cells through down-regulation of uPA.