转录因子Oct-4和Survivin是细胞增殖的关键调控因子,构建针对Oct-4和Survivin基因的双靶向shRNA腺病毒载体Ad5-Dual-shRNA,并研究其对肝癌细胞及移植瘤的生长抑制作用.合成Oct-4和Survivin 基因的shRNA序列,插入腺病毒穿梭载体pDC312,含有shRNA的穿梭载体与腺病毒骨架载体pBHGloxdeltaE13Cre共转染HEK293细胞,经Cre/LoxP位点特异性重组获得重组腺病毒Ad5-Dual-shRNA;腺病毒Ad5-Dual-shRNA感染肝癌细胞系EHBH-H1,经Western blotting检测Oct-4和Survivin基因的表达情况,用3-(4,5-二甲基噻唑-2)-2,5-二苯基四氮唑溴盐染色法(MTT实验)和裸鼠荷瘤实验检测对肿瘤细胞生长的影响.研究结果显示,双靶向重组腺病毒Ad5-Dual-shRNA感染肝癌细胞系EHBH-H1能够有效沉默Oct-4 与Survivin基因的表达,并且在MTT实验和裸鼠荷瘤试验中都显示出较单一靶向的shRNA腺病毒载体Ad5-Surv-shRNA、Ad5-Oct4-shRNA具有更为明显的肿瘤细胞生长抑制作用.实验结果表明,特异性双靶向shRNA腺病毒载体Ad5-Dual-shRNA是一种更为高效的靶向肿瘤基因治疗载体.%The transcriptional factor Oct-4 and Survivin are the key regulatory factors in cancer cell proliferation and mitosis. A dual cancer-specific shRNA adenovirus vector, Ad5-Dual-shRNA, targeting Oct-4 and Survivin genes was constructed by molecular cloning and recombination. After cells were infected with virus, hepatocellular carcinoma cell line EHBH-H1 was used for detecting the expression of Oct-4 and Survivin proteins by Western blotting. The viral cytotoxic effect on cancer cells was detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) reduction assay in vitro, and the inhibition effect on tumor xenografts was observed in nude mice. The results showed that the expression of Oct-4 and Survivin in cancer cell line EHBH-H1 could be silenced markedly by Ad5-Dual-shRNA. In MTT and animal experiments, Ad5-Dual-shRNA also represented much stronger anti-tumor effect on tumor growth than Ad5-Surv-shRNA and Ad5-Oct4-shRNA. From this research we can draw a conclusion that the cancer-specific adenovirus vector expressing dual-shRNA targeting Oct-4 and Survivin genes may provide us a more effective, specific and convenient gene therapy method.
展开▼
