雷帕霉素靶蛋白RNA干扰联合雷帕霉素对人食管癌移植瘤生长和移植瘤组织中雷帕霉素蛋白基因表达的影响

Effects of RNAi combined with rapamycin on expression of mTOR gene in tumor tissue of nude mice transplanted with human esophageal cancer cells

目的:探讨RNA干扰技术联合雷帕霉素对人食管癌裸鼠移植瘤生长和移植瘤组织中雷帕霉素靶蛋白(mTOR)基因表达的影响。方法:①构建裸鼠食管癌EC1细胞移植瘤模型,待肿瘤长出1周后,将荷瘤小鼠随机分为雷帕霉素治疗组[(腹腔注射雷帕霉素,50μg/(kg.次)]、mTOR小分子干扰RNA(siRNA)治疗组[腹腔注射mTORsiRNA,3μg/次]和联合治疗组(先腹腔注射mTORsiRNA,第2天腹腔注射雷帕霉素),另设空白对照组(腹腔注射PBS代替药物)和顺铂治疗组[腹腔注射常规化疗药顺铂,1mg/(kg.次)];每组各5只。连续治疗2周,治疗结束取瘤组织,分析治疗前后移植瘤体积的变化。②采用免疫组化及原位杂交技术观察各组瘤组织中mTOR蛋白及mRNA的表达。结果:①单用雷帕霉素(F=185.00,P<0.001)或mTORsiRNA(F=199.01,P<0.001)均能降低裸鼠移植瘤体积;雷帕霉素和mTORsiRNA有交互作用(F=30.30,P<0.001),2者联合应用后,裸鼠移植瘤体积有更大幅度的下降。顺铂治疗后,裸鼠移植瘤体积与联合治疗的效果差异无统计学意义(t=0.426,P=0.682)。②单用雷帕霉素(F=395.76,F=550.04,P均<0.001)或mTORsiRNA(F=367.58,F=573.39,P均<0.001)均能降低裸鼠移植瘤组织中mTOR蛋白及mRNA的表达;雷帕霉素和mTORsiRNA有交互作用(F=11.68,P=0.004;F=10.23,P=0.006),2者联合应用后,裸鼠移植瘤组织中mTOR蛋白及mRNA的表达有更大幅度的下降。顺铂治疗后,裸鼠移植瘤组织中mTOR蛋白(7.15±0.56)及mRNA(6.88±0.59)的表达与联合治疗的效果差异无统计学意义(t=0.622,P=0.551;t=0.572,P=0.583)。结论:应用RNA干扰技术沉默mTOR基因及应用雷帕霉素治疗均可有效抑制肿瘤的生长,下调裸鼠食管癌移植瘤组织中mTOR蛋白及mRNA的表达,且2者联合效果最佳。

Aim:To investigate the effects of the RNA interference(RNAi)and rapamycin on the expression of the target protein of rapamycin(mTOR)in human esophageal carcinoma xenografts of the nude mice.Methods:The models of human esophageal carcinoma xenografts in nude mice were established,after a week of the tumor growth,they were randomly divided into the rapamycin group,the mTOR siRNA group,the combined treatment group,and the blank control group and the cis-platinum treatment group were served as the control group...