【摘要】 构建由CEA启动子、CMV增强子驱动的融合自杀基因PCDNA3.1(-)CVyCDglyTK表达载体和分别由CEA启动子和巨细胞病毒(CMV)增强子驱动的融合自杀基因PCDNA3.1(-)CEAyCDglyTK、PCDNA3.1(-)CMVyCDglyTK表达载体,以磷酸钙纳米为载体分别转染CEA阳性的人结肠癌细胞株LOVO细胞和CEA阴性的HeLa细胞,Lovo细胞在感染以上3种质粒表达载体后均有yCDglyTK mRNA表达,且对5-FC的敏感性明显增强;HeLa细胞在纳米PCDNA3.1(-)CMVyCDglyTK复合物感染后有yCDglyTK mRNA表达,对5-FC的敏感性增强,而在另外两种复合物感染后则没有yCDglyTK mRNA表达,5-FC对其亦无杀伤作用.结果表明靶向性基因治疗载体能使融合自杀基因在CEA阳性细胞中专一性表达,达到靶向治疗肿瘤的目的.更多还原

【Abstract】 The three expressing plasmids of pcDNA3.1 (-)CVyCDglyTK,pcDNA3.1(-)CEAyCDglyTK, pcDNA3.1 (-)CMV-yCDglyTK were constructed with carcino-embryonic antigen (CEA) promoter and cytomegalovirus(CMV),CEA promoter,cytomegalovirus(CMV) enhancer,respectively. Calcium phosphate nanoparticles(CPNP)was used as vector to transfer the three plasmids into CEA-positive cells(Lovo)and CEA-negative cells(HeLa),respectively. The results showed that expression of yCDglyTK mRNA in all cells transferred by the three plasmids above,which significantly sensitized the cytotoxicity of prodrug 5-FC; expression of yCDglyTK mRNA in HeLa cells after transfected by CPNP- pCDNA3.1(-)CMVyCDglyTK,which enhanced sensitivity of 5-FC,but the other plasmids had no expression of yCDglyTK mRNA and 5-FC had no killing effect. pcDNA3.1(-)CVyCDglyTK might be a promising candidate vector for colon carcinoma gene therapy.更多还原