癌胚抗原(CEA)启动子在肿瘤细胞中的特异表达及介异bak基因诱发凋亡

构建由癌胚抗原 (CEA)启动子控制报道基因增强型绿色荧光蛋白 (EGFP)表达的重组表达质粒pCEA EGFP .用转染细胞后检测荧光的方法对CEA阳性细胞进行简便、直观的检测 ,并结合流式细胞计数对CEA启动子在人结直肠腺癌细胞LS 1 74T、结肠癌细胞SW 4 80、肺腺癌细胞A5 49、人宫颈癌细胞HeLa和人喉癌细胞HEp 2中的活性进行了分析 ,发现其在SW4 80、LS 1 74T、A5 49中活性较强 ,而在HeLa和HEp 2中无活性 .构建由CEA启动子控制凋亡基因bak表达的重组表达质粒pCEA bak ,转染HeLa及SW 4 80细胞 ,用Hoechst332 5 8染色及PI染色 流式细胞计数分析的方法证明 ,pCEA bak转染能够特异性引起SW 4 80细胞的凋亡 .结果表明 ,CEA启动子具有很好的特异性 ,CEA介导bak基因的方法可望用于CEA阳性癌细胞的靶向性基因治疗 .

Specific Expression and Apoptosis Induction with bak Gene in Tumor Cells by Carcinoembryonic Antigen(CEA)Promoter

The reporter gene enhanced green fluorescent protein (EGFP) driven by carcinoembryonic antigen(CEA) promoter was cloned into the recombinant expression plasmid pCEA EGFP.By detection of fluorescence and flow cytometer analysis after transfection,it was found that the CEA promoter could drive the reporter gene expression in colorectal adenocarcinoma cells LS|174T,SW480 and lung cancer cells A549,while no expression in cervix cancer cells HeLa,larynx cancer cells HEp|2.The apoptosis gene %bak% driven by CEA promoter was cloned into the recombinant plasmid pCEA|bak.Hoechst 33258 staining and PI staining/flow cytometer showed that it could induce SW480 cells apoptosis specifically after transfection.The results showed distinct specificity of CEA promoter and suggested the potential of CEA/ bak chimera in the selective gene therapy for CEA positive cancer.