中文摘要：

目的探讨端粒酶催化亚单位启动子/胸腺嘧啶脱氧核苷激酶（hTERTp/tk）基因特异载体在体外靶向性杀伤鼻咽癌细胞的效应。方法通过细胞转染将hTERTp/tk转染鼻咽癌细胞株中,采用RT-PCR及MTT法检测hTERTp/tk/pGL3体外特异性杀伤鼻咽癌细胞的效应及其tk基因、端粒酶表达。结果转染hTERTp/tk/pGL3后可见tk基因表达,端粒酶及其hTERT表达较对照组下降。hTERTp/tk/pGL3能特异性杀伤鼻咽癌HNE1细胞,而对正常成纤维细胞无杀伤作用,hTERTp/tk/pGL3杀伤细胞的效应比阳性对照CMV/tk/pGL3的无选择性杀细胞作用略低。结论hTERTp/tk基因特异表达系统具有靶向性杀伤鼻咽癌细胞的作用及抑制肿瘤细胞端粒酶活性。

英文摘要：

Objective To investigate the targeted killing effect of human telomerase reverse transcriptase promoter （hTERTp） /tk gene on human nasopharyngeal carcinoma （NPC） cells.Methods The recombinant plasmid hTERTp/tk/pGL3 was transfected into human NPC HNE1 cells and the expressions of TK and telomerase were investigated.The targeted killing effect induced by hTERTp/tk on HNE1 cells was assessed using RT-PCR and MTT assay.Results TK gene expression was detected in HNE1 cells transfected by hTERTp/tk/pGL3,and the cells showed reduced telomerase and hTERT expression as compared with the control cells.hTERTp/tk/pGL3 resulted in target killing of HNE1 cells but not of the normal control cells.The tumor cell-killing effect of hTERTp/tk/pGL3 was slightly milder than that of the positive control CMV/tk/pGL3 that produced nonselective cell killing.Conclusion hTERTp/tk,a tumor-specific expression system,allows targeted tumor cell killing and reduces the activity of telomerase in NPC cells in vitro.