放射线对体外培养鼻咽癌细胞细胞周期阻滞、凋亡和抑癌基因p57^(kip2)表达的影响

Effect of Radioactive Rays on Cell Cycle Retardation, Apoptosis and the Expression of Antioncogene p57 kip2 in Cultured Nasopharyngeal Carcinoma Cell Line in vitro

目的研究放射线对鼻咽癌CNE细胞细胞周期阻滞、凋亡和抑癌基因p57kip2蛋白表达的影响。方法运用流式细胞术检测放射线诱导的细胞周期阻滞、凋亡;运用免疫组织化学法检测抑癌基因p57kip2蛋白的表达。结果CNE细胞经照射后,G1期无明显阻滞,S期出现短暂堆积,G2/M期阻滞程度具剂量和时间依赖性,G2/M期阻滞在12h与24h时与照射剂量呈正相关(P<0.01),随照射后时间延长而增强,峰值出现于12Gy24h;细胞凋亡发生率与照射剂量和照射后时间均呈正相关(P<0.01)。照射后p57kip2蛋白表达随照射剂量增加和照射后时间延长而上调(均P<0.01)。结论G2/M期阻滞、细胞凋亡率和p57kip2蛋白均能反映及预测鼻咽癌细胞的放射敏感性。

Objective To study cell cycle retardation, apoptosis and the expression of antioncogene p57^kip2 in nasopharyngeal carcinoma cells. Methods Radioactive rays-induced cell cycle retardation and apoptosis were detected by flow cytometry, and the expression of antioncogene p57^kip2 by immunohistochemistry. Results After irradiation, G1 phase had no obvious retardation and S phase showed transient delay. There was a positive correlation between irradiation dosage and retardation strength in G2/M phase （P〈0.01）. Peak value appeared at 24 h after 12 Gy irradiation, then decreased. There was a positive correlation between apoptosis incidence and irradiation dosage or after-irradiation time extention （P〈0.01）. The expression of p57^kip2 protein was up-regulated along with time prolongation and increased dosage after irradiation （P〈0.01）. Conclusion G2/M phase arrest, apoptosis and the expression of p57^kip2 protein may reflect and predict the radiosensitivity in nasopharyngeal carcinoma cells.