双靶向溶瘤腺病毒对肿瘤细胞及正常细胞的杀伤差异性研究

为了降低溶瘤腺病毒对正常细胞的杀伤作用，提高临床应用上的安全性，构建了一种双靶向溶瘤增殖型腺病毒AdCN103，以人端粒酶逆转录酶（hTERT）启动子代替野生型腺病毒E1A自身的启动子，同时在E1A区缺失保守区域CR2的24 bp.并将AdCN103与两种相应的单靶向溶瘤增殖型腺病毒AdCN101和AdCN102，以及野生型WtAd5相比较，通过MTT,结晶紫以及病毒子代复制实验，观察它们对肿瘤细胞和正常细胞的杀伤性差异.结果表明，AdCN103只能严格地在肿瘤细胞中复制，对肿瘤细胞有较好的杀伤作用，对正常细胞的杀伤性较野生型腺病毒及单靶向腺病毒都弱.实验证明AdCN103能作为新一代的安全的双靶向溶瘤腺病毒载体应用于肿瘤治疗.

Difference of Killing Effects of Dual-targeting Oncolytic Adenovirus on Tumor and Normal Cells(Chinese)

To reduce the killing effect of oncolytic adenovirus on normal cells and get safe clinical application,oncolytic adenovirus AdCN103,a novel dual-targeting tumor specific proliferating virus,was constructed by replacing the wild type adenovirus E1A promoter with the promoter of human telomerase reverse transonptase(hTERT) and mutant E1A lacking CR2 region.The single-controlled recombinant adenovirus was generated with either 24 bp deleted E1A(AdCN101) or wild-type of E1A driven by hTERT promoter(AdCN102).Killing effects of AdCN103 on several different tumor cells and normal cells were detected by crystal violet dye method and MTT assay.The virus replicating ability was assessed by virus progeny assay.The result shows that AdCN103 can selectively replicate in tumor cells and it has an overt cytopathic effect.Meanwhile,there is a dramatic reduction of cytotoxicity in normal cells infected with AdCN103 compared with its corresponding control vectors.Such protocol may have important applications for cancer gene therapies in the future.