没食子酸对鼻咽癌体外放射敏感性的影响  

Effect of Gallic Acid on Radio-sensitivity of Nasopharyngeal Carcinoma in vitro

作　　者：林重华 楚婷[1] 许美凤 李路 师盼 舒易方 瞿家权[1,2,3] LIN Chonghua;CHU Ting;XU Meifeng;LI Lu;SHI Pan;SHU Yifang;QU Jiaquan(Department of Medical Imaging Technology,Medical College,Jishou University, Jishou Hunan 416000, China;Department of Oncology,Qianjiang Central Hospital of Chongqing City, Chongqing 409000, China;Department of Gastroenterology,First Affiliated Hospital,Army Medical University of PLA, Chongqi 400038, China;Raditherapy Room of Oncology Department,First Affiliated Hospital,Army Medical University of PLA, Chongqing 400038, China)

机构地区：[1]吉首大学医学院医学影像技术系,湖南吉首416000 [2]重庆市黔江中心医院肿瘤科,重庆409000 [3]中国人民解放军陆军军医大学第一附属医院消化内科,重庆400038 [4]中国人民解放军陆军军医大学第一附属医院肿瘤科放疗室,重庆400038

出　　处：《医药导报》2021年第4期435-441,共7页Herald of Medicine

基　　金：国家自然科学基金资助项目(81703043);湖南省教育厅优秀青年课题(17B216);林产化工工程湖南省重点实验室开放基金资助项目(2016-12);湖南省研究生创新课题(CX2018B708)。

摘　　要：目的探讨没食子酸对鼻咽癌细胞体外放射敏感性的影响及其分子机制。方法深部X射线多分次亚致死剂量暴露法筛选放疗抵抗鼻咽癌细胞株;放射克隆存活法鉴定鼻咽癌细胞株放疗敏感性差异;MTT法检测没食子酸对细胞活力的影响;Hoechst33258染色荧光显微镜和流式细胞术7-AAD/Annexin V-FITC双染法观察细胞凋亡形态学改变;免疫印记法检测STAT3、c-Jun、PD-L1蛋白表达水平和磷酸化STAT3水平的改变。结果没食子酸对放疗抵抗鼻咽癌细胞株HNE1-IR和放疗敏感细胞株HNE1具有相似的细胞毒作用(IC_(50)值分别是12.58和11.17μmol·L^(-1));2.5μmol·L^(-1)没食子酸增加HNE1-IR细胞体外放疗敏感性(线性二次模型,放射保护因子=1.421,t=2.714,P<0.05);Hoechst33258染色荧光显微镜观察显示,与对照组HNE1细胞比较(Δ凋亡率=6.1%),没食子酸联合放疗增加放疗抵抗鼻咽癌细胞系HNE1-IR细胞凋亡率(Δ凋亡率=14.2%,t=4.799,P<0.05);流式细胞术双染法显示,与对照组HNE1细胞(Δ凋亡率=10.3%)比较,没食子酸联合放疗增加HNE1-IR细胞凋亡率(Δ凋亡率=13.7%,t=2.231,P<0.05);没食子酸联合放疗下调HNE1-IR细胞STAT3和c-Jun的磷酸化水平而对PD-L1蛋白水平无显著改变。结论没食子酸通过抑制放射线诱导的STAT3和c-Jun信号活化,促进放疗抵抗鼻咽癌细胞凋亡,可作为非细胞毒作用的潜在放射增敏剂。Objective To investigate the effects and molecular mechanisms of gallic acid on radiosensitivity of human nasopharyngeal carcinoma cells in vitro.Methods Fractionated radiotherapy with multiply sub-lethal doses of deep X-ray exposure to nasopharyngeal carcinoma cells was employed to establish the radio-resistant nasopharyngeal carcinoma cell line;radiation clonal survival assay was used to identify radiosensitivity of nasopharyngeal carcinoma cell lines;MTT assay was used to detect the effect of gallic acid on cell viability;apoptosis was observed by fluorescence microscopy with Hoechst 33258 staining and flow cytometry with 7-AAD and Annexin V-FITC staining;The expression levels of STAT3,PD-L1,and phosphorylated STAT3 and phosphorylated c-Jun in HNE1-IR cell line after gallic acid treatment with the combination of radiotherapy were detected by Western blot.Results Gallic acid had similar cytotoxicity to radioresistant nasopharyngeal carcinoma cell line HNE1-IR and radiosensitive HNE1 after the treatment(IC_(50)values:12.58 and 11.17μmol·L^(-1),respectively);low doses of gallic acid significantly increased the radiotherapy sensitivity in radioresistant HNE1-IR cells when compared with the control in vitro(linear quadratic model,radiation protection factor=1.421,t=2.714,P<0.05);with the low dose of gallic acid combined with radiotherapy after 72 h,apoptosis rate in HNE1-IR cell line(Δapoptosis rate=6.1%)was significantly increased when compared with control(Δapoptosis rate=14.2%)by Hoechst 33258 staining under fluorescent microscope(t=4.799,P<0.05);the results of apoptosis rate by gallic acid treatment were confirmed by double staining of flow cytometry(Δapoptosis rate of HNE1-IR 13.7%vsΔapoptosis rate of HNE110.3%,t=2.231,P<0.05);the levels of phosphorylated STAT3 and c-Jun in HNE1-IR cell line were down-regulated while protein level of PD-L1 was not significantly changed after the treatment of gallic acid combined with radiotherapy.Conclusion Gallic acid may exert a radiosensitizing effect in nasopharyngea

关 键 词：没食子酸 鼻咽癌 放疗增敏 凋亡 STAT3 PD-L1 

分 类 号：R766.3[医药卫生—耳鼻咽喉科] R979.6[医药卫生—临床医学]