Wang Tian, Xu Qing-quan, Huang Xiao-bo, Wang Xiao-feng
Department of Urology, Peking University People's Hospital, Beijing 100044, China.
Beijing Da Xue Xue Bao Yi Xue Ban. 2013 Aug 18;45(4):527-31.
To investigate the inhibitory effect of silencing androgen receptor (AR) gene by AR short-hairpin RNA (shRNA) on the growth of human prostate cancer xenograft in nude mice.
Human 22RV1 prostate cancer cells were inoculated subcutaneously into nude mice to establish xenograft models of human prostate cancer. Meanwhile, a short-hairpin RNA that was capable of suppressing the expression of AR was constructed and then recombinant plasmids producing AR shRNA were prepared in a large number. The tumor-bearing mice were randomly divided into 2 groups: the control group and the experimental group. When the tumor volume grew to about 300 mm(3), the plasmids prepared previously were injected into the tail veins of the mice once at the dose of 2 μg/g in the experimental group, whereas the mice in the control group was injected with the same amount of saline as control. The tumor volumes were monitored every other day until 14 days after the treatment.At the endpoint,the mice were sacrificed and the tumors were excised, weighed, fixed in buffered-formalin, and embedded in paraffin for the immunohistochemical analysis of AR,Ki-67 (a marker of proliferative cell) levels and apoptotic cell labeling by TUNEL (terminal deoxynucleotidyl transterase-mediated dUTP nick end labeling) assay. A semiquantitative immunohistochemical scoring system, HSCORE system, was used to evaluate the expression of AR and proliferative index/Ki-67 labeling index (PI/Ki-67 LI) and apoptotic index (AI) were used to assess the cell proliferation and cell apoptosis, respectively.
Compared with the control group, the treatment induced an evident inhibitory effect on the tumor growth in the nude mice with prostate cancer. At the endpoint, the tumor volume of (1 199.56±86.48) mm(3) in the experimental group was significantly smaller than that of (1 742.02±98.16) mm3 in the control group (P=0.002). The tumor weight of (1 006.2±79.1) mg in the experimental group significantly decreased compared with that of (1 383.4±74.8) mg in the control group (P=0.005). The AR HSCORE,PI and AI in the experimental group were 25.8±6.7, (26.0±3.1)%, (55.6±7.9)%, respectively, and those in the control group were 268.8± 18.7, (87.6±7.9)%, (27.2±3.9)%, respectively. There were significant differences between the two groups (all P<0.01).
AR shRNA could be injected intravenously to suppress the expression of AR in vivo and hence inhibit the growth of human prostate cancer xenograft in nude mice.
探讨雄激素受体（AR）短发夹RNA（shRNA）沉默AR基因对人前列腺癌裸鼠移植瘤生长的抑制作用。
将人22RV1前列腺癌细胞皮下接种于裸鼠，建立人前列腺癌移植瘤模型。同时，构建能够抑制AR表达的短发夹RNA，大量制备产生AR shRNA的重组质粒。将荷瘤小鼠随机分为2组：对照组和实验组。当肿瘤体积长至约300mm³时，实验组按2μg/g的剂量将先前制备的质粒经尾静脉注射小鼠一次，而对照组小鼠注射等量生理盐水作为对照。每隔一天监测肿瘤体积，直至治疗后14天。实验终点时，处死小鼠，切除肿瘤，称重，用缓冲福尔马林固定，石蜡包埋，用于AR、Ki-67（增殖细胞标志物）水平的免疫组化分析及TUNEL（末端脱氧核苷酸转移酶介导的dUTP缺口末端标记）法检测凋亡细胞标记。采用半定量免疫组化评分系统HSCORE系统评估AR的表达，增殖指数/Ki-67标记指数（PI/Ki-67 LI）和凋亡指数（AI）分别用于评估细胞增殖和细胞凋亡。
与对照组相比，该治疗对前列腺癌裸鼠肿瘤生长具有明显抑制作用。实验终点时，实验组肿瘤体积为（1199.56±86.48）mm³，显著小于对照组的（1742.02±98.16）mm³（P = 0.002）。实验组肿瘤重量为（1006.2±79.1）mg，与对照组的（1383.4±74.8）mg相比显著降低（P = 0.005）。实验组的AR HSCORE、PI和AI分别为25.8±6.7、（26.0±3.1）%、（55.6±7.9）%，对照组分别为268.8±18.7、（87.6±7.9）%、（27.2±3.9）%。两组间差异有统计学意义（均P<0.01）。
静脉注射AR shRNA可在体内抑制AR表达，从而抑制人前列腺癌裸鼠移植瘤生长。
