沉默UHRF1对人食管癌细胞裸鼠移植瘤的放射增敏作用及其机制探讨  

Effect of silencing UHRF1 on radiation sensitivity of human esophageal cancer cell xenografts in nude mice and its mechanism

作　　者：惠蓓娜[1] 刘易婷 马海琳[1] 车少敏[1] 张晓智[1] HUI Beina;LIU Yiting;MA Hailin;CHE Shaomin;ZHANG Xiaozhi(Department of Radiation Oncology,the First Affiliated Hospital of Xi'an Jiaotong University,Shaanxi Xi'an 710061,China;Department of Oncology,Yan'an University Affiliated Hospital,Shaanxi Yan'an 716000,China)

机构地区：[1]西安交通大学第一附属医院放疗科,陕西西安710061 [2]延安大学附属医院肿瘤科,陕西西安716000

出　　处：《现代肿瘤医学》2021年第17期2970-2975,共6页Journal of Modern Oncology

基　　金：陕西省自然科学基础研究计划(编号:2016JM8110)。

摘　　要：目的:探讨沉默食管癌细胞泛素样含PHD和环指域1(ubiquitin-like with PHD and ring finger domains 1,UHRF1)基因对裸鼠移植瘤放射敏感性的影响及可能机制。方法:将20只雌性裸鼠随机分为4组:空载组(NC)、空载+照射组(NC+IR)、沉默UHRF1组(shUHRF1)、沉默UHRF1+照射组(shUHRF1+IR),每组5只,于裸鼠皮下接种Eca109食管癌细胞,构建裸鼠移植瘤模型。成瘤22天(肿瘤直径8 mm左右)开始给予放射线照射,1次2 Gy,共5次,每3 d测量1次移植瘤的最大径(a)和最短径(b),计算肿瘤体积(ab^(2)/2),2周后处死裸鼠称量瘤体质量;采用TUNEL法检测各组移植瘤组织中细胞凋亡情况;Western blot检测各组移植瘤组织中UHRF1蛋白的表达情况;免疫组化方法检测PI3K/AKT/mTOR信号通路关键蛋白的表达。结果:shUHRF1组、NC+IR组以及shUHRF1+IR组中肿瘤体积的增加率均小于NC组(P<0.05),其中shUHRF1+IR组较shUHRF1组、NC+IR组更能抑制移植瘤的生长;shUHRF1组、NC+IR组、shUHRF1+IR组UHRF1蛋白的表达均较NC组下降,其中shUHRF+IR组UHRF1蛋白表达量下降水平高于其余两组(P<0.05);shUHRF1组、NC+IR组、shUHRF1+IR组肿瘤组织内均可观察到肿瘤细胞的凋亡,其中shUHRF1+IR组肿瘤细胞凋亡率明显高于其余两组(P<0.05);与NC组相比,shUHRF1组、NC+IR组、shUHRF1+IR组PTEN蛋白表达水平上调,p-AKT、p-mTOR的蛋白表达下降,其中shUHRF1+IR组PTEN提高水平,p-AKT、p-mTOR的下降水平明显高于shUHRF1组及NC+IR组(P<0.05)。结论:沉默UHRF1基因可以增加人食管癌细胞裸鼠移植瘤的放射敏感性,该作用可能与促进肿瘤细胞凋亡和抑制PI3K/AKT/mTOR信号通路活性有关。Objective:To explore the effect of silencing UHRF1(ubiquitin-like with PHD and ring finger domains 1)on the radiosensitivity of esophageal cancer xenografts and its possible mechanism.Methods:Twenty female BALB/c-nu nude mice were randomly divided into 4 groups:NC group,shUHRF1 group,NC+IR group,shUHRF1+IR group(n=5 for each).The esophagus cancer Eca109 cells were subcutaneously inoculated in nude mice to construct xenograft tumor models.Radiation was given once for 2 Gy for 5 times.The maximum diameter(a)and minimum diameter(b)of the transplanted tumor were measured every 3 days since the the beginning of irradiation.After 2 weeks,the nude mice were sacrificed,the weight of the tumor were measured,TUNEL was used to detect the apoptosis of tumor cells.Western blot was used to detect the expression of UHRF1 protein.Immunohistochemical assay was used to detect the expression of PI3K/AKT/mTOR keyprotein.Results:The growth rates of tumor volume in shUHRF1 group,NC+IR group and shUHRF1+IR group were lower than that in NC group(P<0.05),among them,the shUHRF1+IR group was more able to inhibit the growth of transplanted tumor than other groups,and the weight of transplanted tumor was the lightest(vs shUHRF1 group,NC+IR group,P<0.05).The relative expression of UHRF1 protein in shUHRF1 group,NC+IR group and shUHRF1+IR group decreased compared with that in the NC group,and the UHRF1 protein expression level in the shUHRF1+IR group decreased higher than that in the other two groups(P<0.05),the apoptosis of tumor cells in shUHRF1 group,NC+IR group and shUHRF1+IR group was observed in the tumor tissues,and the apoptosis rate of tumor cells in shUHRF1+IR group was significantly higher than that of the other two groups(P<0.05).Compared with the NC group,PTEN protein expression was up-regulated in the shUHRF1 group,the NC+IR group and the shUHRF1+IR group,while the protein expression of p-AKT and p-mTOR decreased.This trend was most significant in the shUHRF1+IR group(P<0.05).Conclusion:Silencing the UHRF1 can increase the radios

关 键 词：食管癌 UHRF1 移植瘤 放射敏感性 RNA干扰 

分 类 号：R735.1[医药卫生—肿瘤]