表皮生长因子受体反义重组腺病毒联合放射线对乳腺癌细胞的作用

Effects of recombinant epidermal growth factor receptor antisense adenovirus combined with irradiation on breast cnacer cells

目的 探讨表皮生长因子受体 (EGFR)反义重组腺病毒联合放射线对乳腺癌细胞的作用。方法 人EGFR的cDNA片段被反向亚克隆入E1/E3缺失的 5型腺病毒载体中而得到AdE5 ,EGFR反义RNA的表达由CMV启动子控制。进而研究其联合γ射线对人乳腺癌细胞株MDA MB 2 31成克隆能力及细胞周期分布的影响。结果 MDA MB 2 31细胞被AdE5感染后 ,EGFR蛋白质的表达被强烈地抑制。AdE5感染后以γ射线照射细胞 ,成克隆能力被抑制。且这种作用与病毒量和照射剂量相关联。进而流式细胞仪分析显示 ,30 0pfu/细胞的AdE5感染可使MDA -MB- 2 31细胞摆脱对放射线抗拒的G0 +G1期 ,进入对放射线敏感的G2 +M期 ,从而使AdE5联合放射线表现为协同效应。结论 以腺病毒载体介导的EGFR反义RNA转导可有效地用于针对EGFR的反义治疗策略 ,提高放射线对乳腺癌细胞杀灭作用。

Objective To investigate the effects of a recombinant antisense adeno virus for epidermal growth factor receptor (EGFR) combined with irradiation on b reast cancer cells.Methods Human EGFR cDNA fragment was subcloned in the oppos ite orientation to the cytomegaloviral promoter and inserted into a E1/E3-delet e d type 5 adenoviral vector to obtain AdE5 construct which expresses EGFR antisen se RNA. Combined with γ-ray irradiation, its effects on clonogenicity and cell cycle phase distribution were studied in a human breast cancer line MDA-MB-231 . Results EGFR protein expression was dramatically inhibited in MDA-MB-231 cell s after AdE5 infection. The post-irradiation clonogenicity was reduced by AdE5 in a viral and irradiation dose-dependent manner. Further cytometric analysis show e d that AdE5 infection at a?MOI of 300?pfu/cell induced a cell cycle progre ssion from radio-resistant G 0+G 1 phases to radiosensitive G 2+M phases, resultin g in a synergistic effect after combination of these two treatments. Conclusions The t ransduction of EGFR antisense RNA by adenoviral vector is effective for antisens e strategy targeting EGFR, and increases the cell-killing effect of ionizing radiation on breast cancer cells.