Objective： To investigate the inhibitory effects of RNAi （ RNA interference, RNAi） expression vector on CXCR4 expression in prostate carcinoma cell lines. Methods： Small interference RNA （siRNA） expression vectors for CXCR4 gene were constructed and transfected into prostate carcinoma cell lines（PC-3m and LNCaP）with liposomes. T expression of CXCR4 was detected by RT-PCR and western blot. Results： T expression of CXCR4 mRNA and protein in the PC-3m and LNCaP cells was reduced by RNAi expression vectors. The inhibitory rate of CXCR4 mRNA expression in the PC-3m cells was 87.81% ± 10.20% ,56.10% ± 9.32% at the 24th hour and the 48th hour, compared with 56.93% ±8.78% ,49.24% ± 11.23% in LNCaP cells. The inhibitory rate of the expression of CXCR4 protein was 64.71% ± 6.68% ,58.66% ± 11.56% respectively. Conclusion： The expression of CXCR4 gene can effectively be inhibited by RNAi expression vectors.
Yuefeng Du Yifei Xing Fuqing Zeng Peng Lu Xianyin Liu
Objective： CXCR4 is a potential target for cancer gene therapy. In this study, an RNA interference retrovirus vector targeting CXCR4 gene was constructed, and its influence on the invasion of prostate cancer cells by depressing CXCR4 gene expression was analyzed. Methods： the CXCR4-specific siRNA gene was cloned by PCR and inserted into the Pgensil-1 plasmid eonstaining U6 promoter and EGFP, and then the recombinant fragment was sub-cloned into PLXSN and tested by restriction enzyme and sequencing. The virus obtained from transfected PA317 cells was transfected into prostate cancer cells. The expression of CXCR4 mRNA was detected by RT-PCR. The ability of invasion of prostate cancer cells in vitro was estimated by Transwell experiment. Results： it was showed that with the recombinant PLXSN transfection, the expression of CXCR4 mRNA in prostate cancer cells PC-3m and LNCaP was reduced at rates of （84.26±10.20）% and （88.17±11.23）%, respectively. The results of Transwell experiment also showed that the number of cells under micro-membrane were 14.7±3.1 and 18.9±4.2 in the treated group of PC-3m and LNCaP, respectively, compared with 46.9±5.3 and 66.7±6.0 in the control group （P〈0.05）. Conclusion： PLXSN/EGFP-U6-siCXCR4 can significantly depress the expression f CXCR4, by which the invasiveness of prostate cancer cells in vitro was inhibited as well. This recombinant fragment would be helpful in the treatment of prostate cancer.
