探讨融合自杀基因pCEAcd-tk在导入到肺癌细胞后，其体外旁观者效应的细胞差异性。方法：融合基因pCEAcd-tk提取后，脂质体介导的方法转染到6种肺癌细胞株(SPCA-1，GLC-82，A549，SC，HLAMP，L-78)，用MTT法测定在细胞转染前后对前体药物5-氟胞嘧啶（5-FC）和丙氧鸟苷（GCV）的敏感性和在体外的旁观者效应。结果： ① 脂质体介导的基因转染效率很低。② 在6种已转染的肺癌细胞株中，有2种肺癌细胞株（SPCA-1，A549）对前体药物5 FC和GCV有较高的敏感性；③ 旁观者效应显示，2种细胞株（SPCA-1，SC）有强的体外旁观者效应，1种细胞株(A549)有较强的旁观者效应，而另外3种细胞株（GLC-82，HLAMP和L-78）的旁观者效应较差。结论：不同的细胞在转染了融合自杀基因以后，其体外旁观者效应存在较大的差异。

To investigate the variation in vitro bystander effect among human lung cancer cell lines after transfection of pCEAcd-tk. Methods: pCEAcd-tk was extracted and transfected to six human lung cancer cell lines. Their sensitivity to 5-fluorocytosine (5-FC) and ganciclovir (GCV) was measured by MTT assay. Their bystander effect was also determined. Results: 1. The efficiency of lipid mediated gene transfer was very low; 2. Two out of six human lung cancer cell lines(SPCA-1，A549) have a high sensitivity to 5-FC and GCV; 3.Bystander effect: Two out of six human cancer cell lines（SPCA-1，SC） have a good bystander effect, and one out of them（A49）has a intermediate bystander effect, but three out of them （GLC-82，HLAMP and L-78）have a poor bystander effect. Conclusion： There are a variation in vitro bystander effect in six human lung cancer cell lines after transfected with pCEAcd-tk.

R730.51

*本课题受在读博士研究生项目(331098)资助