SKP2和p27^(kip1)在放疗后鼻咽癌CNE2细胞应答中的作用

SKP2 and p27^(kip1) are involved in cellular response to radiation in human nasopharyngeal carcinoma cell line CNE-2

目的探讨SKP2、p27^(kip1)及细胞周期阻滞在放疗后鼻咽癌细胞应答中的作用。方法以人鼻咽低分化鳞癌CNE2细胞株作为研究对象,流式细胞仪检测放疗前后细胞周期变化,West blot检测放疗前后不同时间点SKP2及p27^(kip1)表达的变化。结果放疗后鼻咽癌CNE2细胞株出现G2/M期细胞周期阻滞,低剂量(2Gy)放疗后0.5~1.5h出现SKP2表达短暂下降,同时伴p27^(kip1)表达相应增高;放疗后4h出现SKP2表达升高而p27^(kip1)表达下调。高剂量(6Gy)放疗后1.5h内出现SKP2表达升高,而放疗后2~4h表达下降;而p27^(kip1)表达在放疗后0.5h出现短暂下降,1.5~4h表达上调,两者之间关联性不确定。结论 SKP2、p27^(kip1)和细胞周期阻滞参与放疗后鼻咽癌CNE2细胞的应答反应,且低剂量放疗时,p27^(kip1)表达可能受SKP2调控。

Objective To investigate the expression of SKP2 and p27kip1 in the cel ular response to radiation in human na-sopharyngeal carcinoma cel s CNE-2. Methods The expressions of SKP2 and p27kip1 in human nasopharyngeal carcinoma CNE-2 cel s were detected by Western blot before and after ionizing radiation. Flow cytometry was used for cel cycle Analysis. Results The CNE2 cel s displayed a G2/M cel-cycle arrest after exposure to radiation. Western blot analysis showed a transient increasd expression of p27kip1 and decreased expression of Skp2 at 0.5~1.5h after exposure to low doses ionizing radiation （2Gy）;meanwhile 2~4h after exposure to low dose radiation the expression of Skp2 was up-regulated and p27kip1 down-regulated. However, the expressions pattern of SKP2 and p27kip1 were reversed to above observation after exposure to high doses ionizing radiation （6Gy）. Conclusion The results suggest that SKP2 may contribute to the regulation of p27kip1 and may be a key factor in regulating the cel cycle in response to radiation-induced DNA damage.