腺病毒介导胸苷激酶基因治疗肝癌的实验研究

An Experimental Study about Influence of Adenovirus-Mediated Transfer of the Herpes Simplex Virus Thymidine Kinase Gene and Prodrug on Hepatocarcinoma

目的 :观察腺病毒介导胸苷激酶基因联合抗病毒药物对人肝癌细胞 (HepG2 )的杀伤作用。方法 :利用腺病毒载体将单纯疱疹病毒胸苷激酶基因 (HSV -TK)导入体外培养的HepG2中 ,再加入羟基无环鸟苷 (GCV) ,观察其对HepG2细胞的杀伤效应。结果 :在感染复数 (MOI)小于 1 0 0或GCV浓度小于 4 0 0 μg/ml范围内 ,单独应用载体或GCV ,对培养细胞的形态与存活率均无明显影响。当两者合并应用时 ,GCV在 6.2 5μg/ml和MOI在 33以下 ,即可表现出对HepG2细胞的杀伤 ,且杀伤效应与其浓度存在显著的剂量相关性。将转染了HSV -TK的HepG2细胞与未转染的细胞按不同比例混合 ,证实了“旁观者效应”的存在。凋亡细胞占可计数细胞的 62 .6%。结论 :HSV -TK/GCV对肝癌细胞具有杀伤作用。

Objective To study the effect of adenovirus-mediated transfer of the herpes simplex virus thymidine kinase gene and prodrug on HepG2.Methods Thymidine kinase gene of herpes simplex virus (HSV-TK) mediated by adenovirus vector was transferred into HepG2 in vitro followed by ganciclovir (GCV) addition.The efficacy and toxicity of HSV-TK/GCV on HepG2 were observed.Results HSV-TK or GCV used alone had no obvious toxicity on survival rate or morphologic changes in the cultured cells at MOI less than 100 and GCV lower than 400μg/ml.Combined use of the virus and GCV could present the killing activity to HepG2 cells in a dose dependent manner at lower concentrations of MOI (33) and GCV (6.25μg/ml).The transferred HSV-TK cells mixed with un transferred cells in different proportions revealed the existence of“bystander effect”.Flow cytometer was used to detect the cell apoptosis and the apoptotic cells accounted for 62.8 % of the cells.Conclusion The apoptosis may be an important way of HepG2 killed HSV-TK/GCV.