重组质粒hTERT-siRNA对胰腺癌细胞移植瘤hTERT相关基因及蛋白表达的影响

目的探讨重组质粒pSilencer4.1CMV neo-hTERT-siRNA对胰腺癌细胞BxPC-3裸鼠皮下移植瘤hTERT相关基因及蛋白表达的影响.方法建立人原发性胰腺癌裸鼠皮下移植瘤模型,将荷瘤裸鼠随机分为4组：（1）肿瘤对照组,未作任何处理;（2）空载组,即pSilencer4.1-CMV neo空质粒组;（3）T1组,即重组质粒pSilencer4.1-CMV neo-hTERT1-siRNA组;（4）T2组,即重组质粒pSilencer4.1-CMV neo-hTERT2-siRNA组）.荷瘤裸鼠分组处理30d后,RT-PCR检测各组瘤体中hTERT、Bcl-2、Bax mRNA的表达,免疫组织化学检测各组瘤体中Bcl-2、Bax、p53、VEGF、端粒酶蛋白表达,Western blot检测各组瘤体中端粒酶蛋白表达情况.结果 T1组和T2组hTERT和Bcl-2 mRNA表达较肿瘤对照组和空载组明显降低,BaxmRNA表达明显升高（P〈0.01）.与肿瘤对照组和空载组比较,T1组和T2组Bcl-2 Telomerase、p53和VEGF蛋白表达明显降低,Bax蛋白表达明显升高（P〈0.01）.结论 （1）重组质粒T1和T2能够下调裸鼠移植瘤体内抗凋亡基因hTERT mRNA、Bcl-2 mRNA和蛋白、p53和端粒酶蛋白表达水平,上调促凋亡基因Bax mRNA和蛋白表达水平,其抗胰腺癌作用可能与促进胰腺癌细胞凋亡有关.（2）重组质粒T1和T2能够显著下调裸鼠移植瘤体内VEGF蛋白表达水平,可能具有抑制肿瘤血管生成的作用。

Effects of Recombinant Plasmid hTERT-siRNA on hTRET Related Genes and Proteins Expression in Transplanted Tmour from Pancreatic Cancer Cells

Objective To explore the effects of recombinant plasmid pSilencer4.1CMV neo-hTERT-siRNA on the expression of hTERT related genes and proteins in transplanted tmour from BxPC-3 cells in nude mice.Methods The nude mice model of subcutaneous transplanted tumour from human primary pancreatic cancer was established.The nude mice with transplanted tumour were randomly divided into 4 groups：（1） tumour control group,nude mice received no treatment;（2） empty carrier group,nude mice received pSilencer4.1-CMVneo empty plasmid;（3） T1 group,nude mice received pSilencer4.1-CMVneo-hTERT1-siRNA;（4） T2 group,nude mice received pSilencer4.1-CMVneo-hTERT2-siRNA.Thirty days after treatment,RT-PCR was used to detect the mRNA expression of hTERT,Bcl-2 and Bax in transplanted tmour of nude mice in each group,immunohistochemistry method was used to detect the protein expression of Bcl-2,Bax,p53,VEGF and telomerase,and Western blot was used to detect the protein expression of telomerase.Results The mRNA levels of hTERT and Bcl-2 were lower,and the mRNA levels of Bax were higher in T1 group and T2 group than those in tumour control group and empty carrier group（P〈0.01）.Compared with tumour control group and empty carrier group,the protein levels of Bcl-2,telomerase,p53 and VEGF decreased significantly,and the protein levels of Bax increased significantly in T1 group and T2 group（P〈0.01）.Conclusions（1） Recombinant plasmids T1 and T2 can downregulate the mRNA expression of hTERT,the mRNA and protein expression of Bcl-2,the protein expression of p53 and telomerase（antiapoptotic genes）,upregulate the mRNA and protein expression of Bax（proapoptotic gene） in transplanted tmour of mice,suggests that the anti-pancreatic cancer effects is related with promoting the apoptosis of pancreatic cancer cells;（2） Recombinant plasmids T1 and T2 can downregulate the protein expression of VEGF in in transplanted tmour of mice,suggests that they may inhibit the angiogenesis in tumour.