全反式维甲酸增强单纯疱疹病毒胸苷激酶基因对前列腺癌PC-3细胞旁观者效应的研究

All-trans retinoic acid enhanced the bystander effect of HSV-tK/GCV system on prostate cancer PC-3 cells

目的观察全反式维甲酸(ATRA)对单纯疱疹病毒胸苷激酶基因结合更昔洛韦(HSV-tk/GCV)旁观者效应的增强作用及与Cx43表达的关系。方法用携带HSV-tk基因的腺病毒液感染人前列腺癌PC-3细胞,半定量逆转录-聚合酶链反应(RT-PCR)检测HSV-tk基因整合情况,噻唑蓝(MTT)方法观察ATRA对前列腺癌PC-3,PC-3/TK^+细胞旁观者效应,RT-PCR检测AT- RA诱导Cx43 mRNA表达的作用。结果ATRA显著提高PC-3/TK对GCV的敏感性。在100μmol/L更昔洛韦(GCV)作用下,以10^(-8)mmol/L ATRA与不加ATRA的作用比较,在PC-3,PC-3/TK不同比例混合的各组中,细胞的存活率明显降低,差异有统计学意义(P<0.05)。并观察到10^(-8) mmol/LATRA对GCV旁观者效应的增强作用。RT-PCR结果表明,经ATRA处理的PC-3细胞,其Cx43 mRNA的相对拷贝数比值增高约10倍。结论前列腺癌PC-3细胞中,10^(-6)mmol/L ATRA具有明显增强HSV-tk/GCV旁观者效应的作用。其主要机制是通过ATRA在转录水平诱导Cx43 mR- NA表达上调。

To investigate the enhancement of the bystander effect by all-trans retinoic acid （ATRA） in HSV-tK/GCV system and the correlation with the expression of connexin 43 mRNA. Methods Human prostate cancer cell line PC-3 was transfected with the recombinant retrovirus of HSV-tk gene. HSV-tk gene expression was detected by quantitative RT-PCR. The bystander effect of ATRA on growth of PC-3 and PC-3/TK was examined by MTT. The connexin 43 mRNA expression in PC-3 and PC- 3/TK was analyzed by RT-PCR. Results ATRA markedly increased the sensitivity of PC-3/TK cells to GCV in HSV-tK/GCV system. In the presence of 100 txmol/L GCV, compared with the absence of ATRA, an obvious decrease in survival rate was seen at any given mixture of PC-3 and PC-3/TK cells exposed to 10＂8 mmol/L ATRA （P 〈 0.05 ）. RT-PCR revealed that the ratio of relative copy number of Cx43 mRNA was increased by 10-fold. Condusion In human prostate cancer cell PC-3 line, ATRA can remarkably enhance the bystander effect in the HSV-tk/GCV system by up-regulating the Cx43 mRNA expression.