中文摘要：

目的研究PIWIL2在人类膀胱尿路上皮癌（BTCC）中的表达及siRNA对人类膀胱癌细胞PIWIL2表达的影响。方法采用反转录聚合酶链反应（RT—PCR）检测BTCC46例、腺性膀胱炎21例、癌旁组织17例、正常膀胱组织14例中PIWII．2mRNA的表达；设计合成针对PIWIL2的3个特异性siRNA，转入人类膀胱癌BIU-87细胞，分别采用四甲基偶氮唑蓝、DNA原位末端标记法、RT-PCR和Westernblot检测siRNA对BIU．87细胞生长抑制率（IR）、凋亡指数（AI）和PIWIL2mRNA及其蛋白表达的影响。结果BTCC组织中PIWIL2mRNA的表达率为76．08％（35／40），均显著高于腺性膀胱炎组织f42．86％（9／21）]、癌旁组织[41．17％（7／17）]和正常膀胱组织[7．14％（1／14）]（P=0．008，P：0．010，P：0．000）。BTCC组织中PIWIL2的高表达与肿瘤淋巴结转移、病理分级均密切相关。siRNAI一3组细胞的IR[（37．52±8．84）％、（64．36±9．64）％、（62．94±8．43）％]和AI[（26．18±5．42）％、（38．75±6．19）％、（40．02±5．64）％1均分别显著高于对照组[（1．97±0．02）％、（3．35±0．47）％]（均P=0．000），PIWIL2mRNA及其蛋白表达水平均显著低于对照组；其中siRNA2、3组细胞的IR、AI和对PIWIL2表达的抑制作用均显著高于siRNA1组。结论PIWIL2在BTCC中的高表达，提示其与膀胱癌的发生、发展密切相关；体外转录合成的siRNA可抑制BIU一87细胞PIWIL2的表达，诱导肿瘤细胞凋亡，从而抑制肿瘤细胞生长，提示PIWIL2可作为膀胱肿瘤基因治疗的重要靶点。

英文摘要：

Objective To investigate the gene expression of PIWIL2 in the bladder urothelial carcinoma （BTCC） and siRNA interact on PIWIL2 gene expression in human bladder cancer cell line BIU-87. Methods Semi-quantitative reverse transcription polymerase chain reaction （qRT-PCR） was applied to detect the PIWIL2 expressions in tissues of BTCC （46 cases）, cystitis glandularis（21 cases）, adjacent non-cancerous tissues （17 cases） and normal bladder tissues （7 cases）. 3 specific siRNA targeted PIWIL2 gene were synthesized after designed and transferred. After siRNA was transferred into BIU-87 cells, MTT and TUNELmethods were applied to detect the proliferation inhibitory rate （IR） and apoptosis index （AI） in BIU-87 cells, qRT-PCR and Western blot were used to examine effects of siRNA on the expressions of the PIWIL2 gene and protein, respectively. Results The expression rate of P1WIL2 mRNA in BTCC tissues was 76.08 %（35/46） and significantly higher than those in the cystitis glandularis tissues （42.86 %, 9/21）, adjacent non-cancerous tissues （41.17 %, 7/17） and normal tissues （7.14 %, 1/14） （P = 0.008, P = 0.010, P = 0.000）. The IR [（37.52±8.84） %, （64.36±9.64） %] and （62.94±8.43） %] and AI [（26.18±5.42） %, （38.75±6.19） % and （40.02±5.64） %] of BIU-87 cells in the siRNA 1-3 groups were respectively significantly higher than those [（1.97±0.02） % and （3.35±0.47） %] in the control group（P=0.000）, and expressions of PIWIL2 mRNA and protein in the siRNA groups were both lower than those in the control group. Moreover, the effects Of siRNA 2 group and siRNA 3 group on inhibiting PIWIL2 expression, IR and AI of BIU-87 cells were stronger than siRNA 1 group. Conclusion The over-expression of PIWIL2 suggested that it played an important role in the mechanism of development and malignant progression of BTCC. The siRNA of transcription can significantly inhibit its expression, induce cell apoptosis and inhibit the growth of BIU-87 cells which mi