Cheng J, Leng X, Peng J
Department of Surgery, People's Hospital, Beijng Medical University, Beijing 100044, China.
Zhonghua Yi Xue Za Zhi. 2000 Jun;80(6):461-3.
To construct plasmids that express target genes in hepatoma cell line using adeno-associated virus (AAV) vectors containing human AFP promoter.
Primers containing specific enzyme-cutting sites were designed to amplify the alpha-fetoprotein promoter (AFP promoter) from human genome. The promoter was cloned into pTR-UF5, a plasmid containing GFP reporter gene, resulting in the recombinant AAV plasmid containing the reporter gene (rAAV-AFP-GFP). Blunted ligation was used to construct the recombinant AAV vector plasmid containing human wild p53 gene (rAAV-AFP-53). The plasmid rAAV-AFP-GFP was used to transfect the AFP-expressing Hep G(2) and non-AFP-expressing 293 cell lines, respectively, to measure the function of the cloned AFP promoter. Flow cytometry was used to measure the effect of rAAV-AFP-53 on hepatoma cell line HLE.
rAAV-AFP-53 and rAAV-AFP-GFP were verified by DNA sequencing and enzyme digestion to carry human AFP promoter. Cell transfection of rAAV-AFP-GFP showed selective expression in AFP-positive hepatoma cell lines with a transfection rate of 36.5%; rAAV-AFP-53 induced apoptosis rate was 73.88%.
Two adeno-associated virus plasmids are successfully constructed that carry p53 gene and reporter gene, respectively, guided by AFP promoter. The former one shows a hepatoma-specific apoptosis-inducing effect.
利用含人甲胎蛋白启动子的腺相关病毒(AAV)载体构建在肝癌细胞系中表达靶基因的质粒。
设计含特定酶切位点的引物,从人类基因组中扩增甲胎蛋白启动子(AFP启动子)。将该启动子克隆至含绿色荧光蛋白(GFP)报告基因的质粒pTR-UF5中,构建出含报告基因的重组AAV质粒(rAAV-AFP-GFP)。采用平端连接构建含人野生型p53基因的重组AAV载体质粒(rAAV-AFP-53)。分别用质粒rAAV-AFP-GFP转染表达AFP的Hep G(2)细胞系和不表达AFP的293细胞系,检测克隆的AFP启动子的功能。采用流式细胞术检测rAAV-AFP-53对肝癌细胞系HLE的作用。
经DNA测序和酶切验证,rAAV-AFP-53和rAAV-AFP-GFP携带人AFP启动子。rAAV-AFP-GFP转染细胞在AFP阳性肝癌细胞系中呈选择性表达,转染率为36.5%;rAAV-AFP-53诱导的凋亡率为73.88%。
成功构建了分别携带p53基因和报告基因的两种腺相关病毒质粒,二者均由AFP启动子引导。前者显示出肝癌特异性的诱导凋亡作用。