^(60)Co-γ照射对肺癌A549细胞VEGF表达的影响

Time effect of ^(60)Co γ-rays irradiation on expression of VEGF in lung adenocarcinoma cells A549

目的:探讨60Co-γ射线照射肺癌A549细胞后血管内皮生长因子(vascula endothelial growth factor,VEGF)表达变化。方法:2Gy剂量60Co-γ射线照射肺癌A549细胞,以荧光定量PCR法检测照射后4、12、24、48、72h VEGF mRNA表达改变,以ELISA法检测各组培养液上清中VEGF蛋白表达量变化。结果:以对照组(未照射组)VEGF mRNA表达量为1,照射后4h VEGF mRNA表达开始升高,12、24小时达到高峰(8.83±3.01,P<0.05;14.67±7.18,P<0.01),48-72h随后降至接近对照组水平。ELISA检测培养液上清中VEGF蛋白表达量,在照射后4h降低,随后开始升高,24、48h达到高峰(600.86±20.87,P<0.05;594.75±2.52,P<0.05),72h降至对照组水平。结论:2Gy剂量60Co-γ射线照射肺癌A549细胞后早期VEGF表达升高,我们推测此时可能是联合抗VEGF药物抑制肺癌转移的最佳时机。

Objective ：To investigate the effect of ionizing radiation on vascular endothelial growth factor （VEGF） expression in human lung adenocarcinoma ceils A549. Methods：AS49 cells were irradiated with 2Gy ^60Coγ -rays, and cultured for 4,12,24,48 and 72 hours separately. VEGF mRNA of the irradiated cells were quantified by fluorescent quantitative PCR and ELISA assay was used to detect the VEGF protein levels in culture supernatant. Results： Compared with the control group, levels of VEGF mRNA were increased at 4 h and an apparent maximum change （ 8.83 ± 3.01,14.67 ± 7.18,P 〈 0.05 ） occurred at 12 - 24h, then the level declined to normal at 48 - 72h. The levels of VEGF protein were decreased at 4h and increased gradually soon after. The peak occurred at 24 - 48h after exposure （600.86 ±20.87,594.75 ± 2.52, P 〈 0.05 ）, and declined to normal level at 72h. Conclusion： The expression of VEGF in human lung adenocarcinoma ceils A549 increased significantly in short time after 60^Co γ- rays irradiation with 2 Gy dose. Combined with medicine against VEGF gene during this period maybe the best time to inhibit tumor metastasis efficiently.