Transduction of suicide gene into malignant mesothelioma with tumor-specific promoter

为了实现转染的自杀基因在恶性间皮瘤细胞中的特异性表达，我们应用了角蛋白19（K19）基因的增强子-启动子融合序列。北方印迹分析表明，K19 mRNA在H2052间皮瘤细胞系中表达最丰富。随后，在荧光素酶报告试验中，K19启动子（260 bp）在H2052细胞中表现出比其他两种细胞系更高的启动子活性。此外，将K19基因的3 ′增强子（80 bp）连接到K19启动子的上游，充分增强了启动子活性。将含有K19增强子-启动子结合型胸苷激酶基因的表达载体（pK 19-TK）转染H2052细胞后，在体内外实验中，pK 19-TK转染细胞对GCV的敏感性均高于未转染细胞。K19增强子-启动子序列似乎是特异性的，并且对于转染的自杀基因在恶性间皮瘤细胞中的表达足够有效。

To achieve the specific expression of a transfected suicide gene in malignant mesothelioma cells, we applied the enhancer-promoter fusion sequence of the keratin 19(K19)gene. Northern blot analysis of three mesothelioma cell lines demonstrated that K19 mRNA was expressed most abundantly in the H2052 mesothelioma cell line. Subsequently, in a luciferase reporting assay, K19 promoter(260 bp)exhibited higher promoter activity in H2052 cells than in the other two cell lines. In addition, ligation of a 3' enhancer(80 bp)of the K19 gene to upstream of the K19 promoter sufficiently enhanced the promoter activity. After transfecting an expression vector containing the K19 enhancer-promoter bound thymidine kinase gene(pK19-TK)into the H2052 cells, the pK19-TK transfected cells become more sensitive to GCV than non-transfected cells in vitro and in vivo. The K19 enhancer-promoter sequence seemed to be specific and efficient enough for the expression of the transfected suicide gene in malignant mesothelioma cells.