调控食管癌癌胚抗原基因表达对溶瘤腺病毒H101抗癌作用的影响

Effect of CEA gene regulation on the anti-tumor activity of oncolytic adenovirus HIO1 to esophageal carcinoma

目的研究调控食管癌癌胚抗原（CEA）基因表达对溶瘤腺病毒H101抗癌作用的影响，探讨影响H101敏感性的内在因素。方法选择CEA低表达的EC9706细胞株（EC9706．SCEA）和CEA过表达的EC9706细胞株（EC9-06-CEA）复苏培养，细胞生长实验检测调控EC9706细胞CEA基因表达对细胞生长的影响，通过细胞毒性实验和裸鼠体内实验检测H101对不同CEA表达水平EC9706细胞的杀伤效果。结果细胞生长实验表明，EC9706-SCEA、EC9706-CEA和EC9706细胞群体倍增时间分别为（30．9±2．0）h、（31．1±2．5）h和（29．1±2．6）h，差异无统计学意义（P〉0．05）。细胞毒性实验显示，当感染复数（MOI）〉10．01PFU时，H101对EC9706-SCEA细胞的抑制率明显高于EC9706、EC9706-CEA、EC9706-siCon和EC9706-Con细胞（P〈0．05）。不同时间各组裸鼠移植瘤体积测定显示，H101对治疗组裸鼠皮下移植瘤的生长均有抑制作用，但其对EC9706-SCEA治疗组移植瘤生长的抑制作用（抑瘤率为61．5％～74．5％）显著强于EC9706治疗组（抑瘤率为35．5％～44．8％）和EC9706-CEA治疗组（抑瘤率为32．3％～38．5％），差异有统计学意义（P〈0．05）。结论溶瘤病毒H101对EC9706-SCEA细胞的杀伤力明显增强。沉默CEA基因的表达，有望成为提高溶瘤病毒H101抗癌效果的新途径。

Objective To study the effect of CEA gene regulation on the anti-tumor activity of oncolytic adenovirus H101 to esophageal carcinoma, and to explore the intrinsic factors influencing H101 sensitivity. Methods Stable human esophageal cancer cell line EC9706 cells with lower （EC9706-SCEA） and higher CEA expression （EC9706-CEA） were chosen, thawed and cultured, and then to analyse the influence of CEA expressed at different levels on cell growth. The eytotoxic effect of H101 was assayed by in vitro and nude mouse in vivo. Results The cell growth experiment showed that the population doubling time of EC9706-SCEA, EC9706-CEA and EC9706 cells were （30.9± 2.0） h, （31.1± 2.5） h and （29.1 ± 2.6） h, respectively, showing no significant difference among them （ P 〉 0.05 ）. The eytotoxie activity of H101 was higher on EC9706-SCEA than on other four groups, when MOI was ≥0.01 PFU （P 〈0.05）. The mouse experiment showed that H101 inhibited the growth of transplanted tumors in all experimental groups. Its effect on CEA-silenced tumors （ inhibition rate was 61.5% to 74.5% ） was siguifieantly higher than that on CEA-overexpression tumors （32.3% to 38.5% ） and control EC9706 transplanted tumors （35.5% to 44.8% ）. There was a significant difference between them （ P 〈 0.05 ）. Conclusions The results in vitro and in vivo experiments show that H101 can enhance the cytotoxic effect on EC9706 cells with lower CEA expression. To silence the expression of CEA may provide a novel strategy for target gene therapy of esophageal carcinoma.