X射线对人鼻咽癌CNE2及CNE2/DDP细胞自噬相关基因的影响

The influence of autophagy-related genes about X-Ray on nasopharyngeal carcinoma CNE2 and CNE2/DDP cells

目的:研究放疗抵抗与自噬的关系,为使用药物调节自噬水平来提高鼻咽癌放疗敏感性提供理论基础。方法:采用流式细胞术分析CNE2及CNE2/DDP细胞照射前后的细胞周期分布;实时荧光定量PCR和免疫荧光染色检测CNE2及CNE2/DDP细胞中自噬特异性基因Beclin 1及微管相关蛋白轻链3β(MAPLC3β)的表达水平。结果:射线照射后CNE2及CNE2/DDP细胞的G2-M期增多,与放射剂量呈正相关(P<0.05),CNE2/DDP细胞的G2-M期阻滞比CNE2明显(P<0.05)。射线照射后CNE2及CNE2/DDP细胞的Beclin1及MAPLC3β的表达水平增高,与放射剂量呈正相关(P<0.05)。CNE2/DDP细胞的Beclin1及MAPLC3β表达水平均低于CNE2细胞,差异有统计学意义(P<0.05)。结论:自噬性死亡可能是放射治疗后人鼻咽癌CNE2及CNE2/DDP细胞的死亡方式之一,而CNE2/DDP细胞的放射抵抗可能与低水平的自噬有关。

Objective：To study the relationship between the radiotherapy resistance and autophagy.To provide a theoretiacal basis for drugs that regulate autophagy to improve radiotherapy sensitivity.Method：Flow cytometry（FCM）was performed to analyze the distribution of the cell cycle of CNE2 and CNE2/DDP cells under the action of X radiation.The expression of autopagy-specific gene Beclin1 and microtubule-associated protein light chain 3β（MAPLC3β）in CNE2 and CNE2/DDP cells was determined by real time PCR and Immumofluorescence staining.Result：CNE2/DDP and their parental CNE2 cells produced the G2-M phase arrest under the action of X radiation.With the radiation dose increasing,The cells which in the G2-M phase were more and more（P〈0.05）.The G2-M phase arrest in CNE2/DDP cells was more obvious than in CNE2 cells（P〈0.05）.The expression of Beclin1 and MAPLC3β in CNE2 and CNE2/DDP cells increased under the action of X radiation.What′s more,the raise was more and more obvious with the increase of the irradiation dose（P〈0.05）.The expression levels of Beclin1 and MAPLC3β in CNE2/DDP was lower than that in CNE2 cells（P〈0.05）.Conclusion：Autophagic cell death may be the one manner of death in nasopharyngeal carcinoma CNE2 and CNE2/DDP cells under the action of X radiation.The radiation resistance of CNE2/DDP cells may be related to the low expression of autophagy-related genes.