婴儿双歧杆菌介导HSV-TK/GCV对前列腺癌PC-3细胞裸鼠移植瘤细胞凋亡的影响

Effects of HSV-TK/GCV suicide gene therapy system mediated by bifidobacterium infantis on cell apoptosis of prostate cancer PC-3 cell xenografts in nude mice

摘要:

目的：研究婴儿双歧杆菌（bifidobacterium infantis，BI）介导单纯疱疹病毒胸苷激酶（herpes simplex virus thymidine ki－nase，HSV-TK）/丙氧鸟苷（ganciclovir，GCV）自杀基因系统对PC-3细胞裸鼠移植瘤细胞凋亡的影响。方法：采用前列腺癌PC-3细胞悬液皮下注射法建立裸鼠前列腺癌模型，并随机分为4组，每组各12例，分别经尾静脉注射BI-pGEX-TK（重组质粒组）、BI-pGEX-5X-1（空质粒组）、BI（空婴儿双歧杆菌组）和生理盐水（生理盐水组），联合腹腔注射GCV，4周后，称取裸鼠质量及肿瘤质量。TUNEL法检测各组肿瘤细胞凋亡情况，real-time PCR、Western blot分别检测各组肿瘤组织中Fas、FAP-1、casepase3和casepase8的mRNA 及蛋白表达水平。结果：重组质粒组荷瘤裸鼠体质量明显高于其余3组（F=12.952，P=0.000），肿瘤组织质量明显降低（F=7.795，P=0.000）；重组质粒组凋亡指数明显高于其他3组（F=45.895，P=0.000）；重组质粒组Fas mRNA（F=70.077，P=0.000）、casepase3 mRNA（F=70.611，P=0.000）和casepase8 mRNA（F=73.781，P=0.000）的表达明显上调，FAP-1 mRNA（F=46.880，P=0.000）的表达明显下调。重组质粒组Fas蛋白（F=664.116，P=0.000）、casepase3蛋白（F=203.090，P=0.000）和casepase8蛋白（F=654.354，P=0.000）的表达明显上调，FAP-1蛋白（F=318.989，P=0.000）的表达明显下调。结论：婴儿双歧杆菌介导HSV-TK/GCV自杀基因系统可能通过影响Fas介导凋亡信号通路，诱导荷瘤裸鼠前列腺癌细胞的凋亡，发挥抑癌作用。

Abstract:

Objective：To investigate the effect of bifidobacterium infantis（BI）-mediated herpes simplex virus thymidine kinase（HSV-TK）/ganciclovir（GCV） suicide gene therapy system on cell apoptosis of prostate cancer PC-3 cell xenografts in nude mice. Methods：The prostate cancer model was established by subcutaneous injection of human prostate cancer cell line PC-3 into nude mice. The model mice were randomly divided into 4 groups，which were treated by intraperitoneal injection of GCV in combination with tail vein injection of BI carrying recombinant plasmid BI-pGEX-TK（recombinant plasmid group），BI carrying empty plasmid BI-pGEX-5x-1（empty plasmid group），BI（BI group） and normal saline（normal saline group）. After 4 weeks of treatment，tumor weights and nude mice weights were recorded. The apoptosis of tumor was detected by TUNEL assay. The expression of Fas，FAP-1，casepase3 and casepase8 were determined by real-time qPCR and Western blot，respectively. Results：After treatment，comparing with those of empty plasmid group，BI group and normal saline group，the nude mice weights in recombinant plasmid group increased（F=12.952，P=0.000），the tumor weights decreased（F=7.795，P=0.000）. The apoptosis index of recombinant plasmid group was obviously higher than that of the other three groups（F=45.895，P=0.000）. Comparing with the other three groups，the mRNA expression of Fas（F=70.077，P=0.000），casepase3（F=70.611，P=0.000） and casepase8（F=73.781，P=0.000） in recombinant plasmid group increased，but the mRNA expression of FAP-1（F=46.880，P=0.000） decreased. Protein expression of Fas（F=664.116，P=0.000），casepase3 F=203.090，P=0.000） and casepase8（F=654.354，P=0.000） in recombinant plasmid group increased，but the expression of FAP-1 protein（F=318.989，P=0.000） decreased. Conclusion：The BI-mediated HSV-TK/GCV suicide gene therapy system can inhibit nude mice prostate cancer progression effectively，probably through affecting Fas mediated apoptosis signaling pathways，inducing to nude mice prostate cancer cells apoptosis and playing a role in tumor suppression.