ODDD乏氧靶向HSV1-TK/GCV系统对体外肝癌细胞的杀伤作用

目的:探讨pEGFP-TK-ODDD基因表达载体乏氧特异性杀伤肝癌细胞的可行性。方法:通过LipofectamineTM2000将重组基因质粒pEGFP-TK-ODDD在肝癌细胞株SMMC7721和HepG2中进行瞬时转染。流式细胞仪分析EGFP的表达强度分析质粒转染效率。MTT法检测GCV作用24小时后转染细胞在不同氧浓度下的生存率。结果:SMMC7721细胞和HepG2细胞质粒转染效率分别为33.23%和36.97%;MTT结果显示,GCV浓度为12.5 mg/L时,缺氧环境下转染pEGFP-TK-ODDD基因表达载体的SMMC7721细胞和HepG2细胞存活率,细胞的生存率分别为81.25%和76.55%,明显低于对正常氧环境中细胞生存率的92.12%和94.36%(P<0.05)。结论:ODDD可以特异的调控HSV1-TK/GCV系统对乏氧肝癌细胞的靶向杀伤作用。

Specific killing of hepatocellular carcinoma cells under hypoxia conditions by thymidine kinase gene controlled ODDD sequence

Objective:To develop a potentially therapeutic DNA vaccine highly specific for hepatocellular carcinoma cells under hypoxia conditons controlled by ODDD.Methods:Suicide gene HSV-TK was transferred into SMMC7721 cells and HepG2 cells with a pEGFP-ODDD vector with LipofectamineTM2000.Following hypoxic exposure for 24h,cells were treated with different concentrations of prodrugs GCV.The cytotoxic efficacy of GCV on cells was evaluated by MTT assay.Results:SMMC7721 cells and HepG2 cells had the same transfection rate of pEGFP-TK-ODDD with 33.23% and 36.97%(P>0.05).GCV showed in vitro cytotoxicity to cells in a dose-dependent manner.Compared with the normoxic sample,cell survival of SMMC7721 cells and HepG2 cells under hypoxia conditons transfected with the same plasmid pEGFP-TK-ODDD were reduced to 81.25% and 76.55% at GCV concentration of 12.5 mg/L.Conclusion:HSV-TK/GCV GDEPT controlled by the region of ODDD had the specific killing effect in SMMC7721 cells and HepG2 cells under hypoxia conditions.