沉默cIAP-1基因对肝癌SMMC-7721细胞放疗敏感性的影响

IAP-1 gene silencing enhanced the radiosensitivity of liver cancer SMMC-7721 cells

目的探讨细胞凋亡抑制蛋白1（cIAP-1）对肝癌SMMC-7721细胞放疗敏感性的影响。方法首先构建特异性沉默cIAP-1基因的pGCsi—H1-shRNA载体；然后通过CCK8试验、蛋白印迹检测（Western blot）、实时定量．PCR（qRT—PCR）、流式细胞仪和凋亡检测等方法分析照射处理后细胞活性、细胞周期以及细胞凋亡的变化。结果分别在不同照射剂量（1Gy、4Gy、7Gy、10Gy）条件下检测肝癌SMMC-7721细胞24h细胞增殖率。与对照组（pGCsi—H1-control）比较，沉默cIAP-1基因细胞组（pGCsi—H1-shRNA）在各个照射剂量条件下细胞增殖率均明显降低，并且存在照射剂量依赖性（P〈0．05）。与未照射处理组比较，照射处理组SMMC-7721细胞明显阻滞在G1／G0期（P〈0．01），处于S期细胞比例也明显降低（P〈0．01）。与对照组比较，沉默cIAP-1基因组细胞周期明显阻滞在G1／G0期（P〈0．05），沉默cIAP-1基因组细胞周期凋亡百分比显著增加（P〈0．05）。结论沉默cIAP-1表达可提高肝癌对放疗的敏感性，并能协同放疗抑制肝癌细胞的增殖率。

Objective To explore the effect of cellular inhibitor of apoptosis proteinl （ cIAP-1 ） gene on the radiosensitivity of SMMC-7721 cells. Methods We silenced cIAP-1 expressions by the shRNA technology, and then we detected the changes of cell proliferation, cell cycle and cell apoptosis by CCK8 assay, Western blot, qRT-PCR and flow cytometry after the radiotherapy. Results The cell proliferation rate of liver cancer SMMC-7721 cells at different radiation doses of 1 Gy, 4 Gy, 7 Gy and 10 Gy was detected. Comparing with control group （pGCsi-H1-control）, the cell proliferation in cIAP-1 silencing group （pGCsi- H1-shRNA） was significantly reduced at various radiation doses, and the effect was dose-dependent （P 〈 0. 05）. G1/G0 phase arrest was observed after radiation （P 〈0.01 ）, and the proportion of cells in S phase was significantly reduced compared with control （P 〈 0.01 ）. Compared with control group, G1/G0 phase arrest was detected （ P 〈 0.05 ）, and the percentage of cell apoptosis was increased significantly in cIAP-1 silencing group （P 〈 0.05 ）. Conclusion cIAP-1 silencing can enhance the radiosensitivity of liver cancer cells, and inhibit cell proliferation by promoting the anti-tumor effect of radiation.