mTOR对非激素依赖性前列腺癌的作用研究

Study on the Effect of mTOR on Androgen-independent Prostate Cancer

[目的]探讨mTOR对非激素依赖性前列腺癌裸鼠移植瘤的影响及作用机制。[方法]背部皮下注射LNCaP细胞复制裸鼠前列腺癌模型,去势同时瘤体内注射mTOR shRNA慢病毒颗粒,记录移植瘤进入激素耐药的时间,同时测量肿瘤组织体积及重量;RT-PCR和Western blot方法分别检测肿瘤组织中mTOR、CgA、NSE的mRNA和蛋白表达情况;采用PI染色和AV/PI染色联合流式细胞术检测肿瘤组织中细胞周期变化和细胞凋亡情况。[结果]与对照组相比,瘤体内注射mTOR shRNA慢病毒颗粒后,移植瘤进入激素耐药时间有所延长,肿瘤组织的体积和重量均显著下降(P<0.05),细胞周期中S期细胞所占比例减少、凋亡细胞有所增加,同时,CgA和NSE表达下降(P<0.05)。[结论]瘤体内注射mTOR shRNA慢病毒颗粒可抑制前列腺癌神经内分泌分化,促进移植瘤组织凋亡、抑制细胞增殖。

[Purpose] To investigate the effect of mTOR on androgen-independent prostate cancer and its mechanisms.[Methods] Subcutaneous xenotransplantation tumor model was established by injection of LNCaP cells into the back of nude mice.The nude mice was castrated and injected with mTOR shRNA lentivirus particles,then tumor volumes and weights were measured.RT-PCR and Western blot were used to detect the expressions of mTOR,CgA and NSE mRNA and proteins respectively.The effects of mTOR shRNA on the cell cycle and apoptosis of tumor cells were examined by PI and AV/PI staining combined with flow cytometry.[Results] Compared with the control group,the duration of androgen resistance in mTOR shRNA group was longer and tumor weight and volume were decreased（P0.05）.The ratio of cells in S phase released and the ratio of apoptosis cells increased.Meanwhile,the expression of CgA and NSE were obviously decreased.[Conclusion] Intratumor injection with mTOR shRNA lentivirus particles could inhibit the neuroendocrine differentiaton in prostate cancer,stimulate tumor cells apoptosis and inhibit proliferation.