小细胞肺癌碱基切除修复蛋白表达和免疫细胞浸润与预后关系的研究  

Relationship of base excision repair pathway-related proteins with immune cell infiltration and prognosis in small cell lung cancer

作　　者：李超凡 陈天一 陈骞 杨宇馨[1] 王东[1] LI Chaofan;CHEN Tianyi;CHEN Qian;YANG Yuxin;WANG Dong(Cancer Center,Army Medical Center of PLA/Daping Hospital of Third Military Medical University,Chongqing,China)

机构地区：[1]陆军特色医学中心(第三军医大学大坪医院)肿瘤中心,重庆

出　　处：《陆军军医大学学报》2025年第9期935-947,共13页Journal of Army Medical University

基　　金：国家自然科学基金面上项目(82073170);重庆市医学青年拔尖人才项目(YXQN202466)。

摘　　要：目的 观察碱基切除修复(base excision repair,BER)蛋白在小细胞肺癌(small cell lung cancer,SCLC)组织中的表达水平,分析其与SCLC患者预后的关系,及其与肿瘤免疫微环境的关系。方法 采用回顾性队列研究设计方案,纳入2018年12月至2023年6月在陆军特色医学中心胸外科接受手术治疗的局限期SCLC患者共74例。通过免疫组化染色分析蛋白在SCLC组织中的表达,包括脱嘌呤/脱嘧啶核酸内切酶1(apurinic/apyrimidinic endonuclease 1,APE1)、8-羟基鸟嘌呤DNA糖苷酶1(8-oxoguanine DNA glycosylase 1,OGG1)、DNA聚合酶β(DNA polymerase β,POLβ)、X射线交错互补修复蛋白1(X-ray repair cross complementing protein 1,XRCC1)、ATP依赖性DNA连接酶Ⅰ(recombinant ATP dependent DNA ligaseⅠ,LIGⅠ),以及免疫细胞CD3^(+)T、CD8^(+)T、CD68^(+)巨噬细胞浸润情况;使用χ^(2)检验分析BER蛋白表达与SCLC患者临床病理特征的关系,Kaplan-Meier生存曲线分析BER蛋白及免疫细胞对SCLC患者无病生存率和总生存率的影响,多因素Cox回归评估无病生存率的影响因素,Spearman分析BER蛋白表达和免疫细胞浸润的相关性。采用瞬时转染技术在SCLC细胞系H196中分别过表达APE1、POLβ及LIGⅠ蛋白,实验分为:阴性对照组(negative control,NC),转染空载质粒;过表达组(overexpression,OE),转染目标基因质粒(OEAPE1、OEPOLβ、OELIGⅠ)。CCK-8及TUNEL检测NC组和OE组对顺铂敏感性的影响。裸鼠皮下移植瘤实验采用简单随机分组法将裸鼠分为(n=6):WT组、E3330组、顺铂组、顺铂+E3330组,并观察E3330联合顺铂对肿瘤生长的影响。结果 BER通路关键蛋白的表达水平与患者性别、年龄、吸烟史、肿瘤部位、Ki67指数及TNM分期等临床病理特征无显著相关性(P均>0.05);BER蛋白中APE1、POLβ、LIGⅠ低表达组的无病生存率高于高表达组(P<0.05),而在免疫细胞浸润中CD3^(+)T细胞高水平组的无病生存率高于低水平组(P=0.043)。多因素Cox回归�Objective To observe the expression levels of base excision repair(BER) pathwayrelated proteins in small cell lung cancer(SCLC) tissues,and analyze their relationship with the prognosis and tumor immune microenvironment.Methods A retrospective cohort study was conducted on 74 patients with limited-stage SCLC undergoing surgical treatment in our medical center from December 2018 to June 2023.Immunohistochemical staining was performed to analyze the protein expression of BER pathway components,apurinic/apyrimidinic endonuclease 1(APE1),8-oxoguanine DNA glycosylase 1(OGG1),DNA polymerase β(POLβ),X-ray repair cross-complementing protein 1(XRCC1),ATP-dependent DNA ligase Ⅰ(LIG Ⅰ),and immune cell infiltration markers of CD3^(+)T cells,CD8^(+)T cells,CD68^(+)macrophages in SCLC tissues.Chisquare test was applied to analyze the relationship of BER protein expression and clinicopathological features;Kaplan-Meier survival curve was plotted to evaluate the impacts of BER protein expression and immune cells on disease-free survival(DFS) and overall survival(OS),multivariate Cox regression analysis was utilized to identify DFS prognostic factors,and Spearman correlation analysis was performed to analyze the correlation of BER-immune cell infiltration.In in vitro experiments,transient transfection was applied in H196 cells to overexpress APE1/POLβ/LIG Ⅰ,respectively.Thus,the cells were divided into negative control(NC,empty vector) and overexpression(OE,target plasmids) groups.CCK-8 and TUNEL assays were employed to determine the effects of OEAPE1,OEPOLβ and OELIG Ⅰ on cell sensitivity to cisplatin.In in vivo experiments,nude mice bearing xenograft tumors were grouped into WT,E3330(APE1 inhibitor),cisplatin,and cisplatin+E3330 groups to determine the effects of the combination therapy on tumor growth.Results There were no significant correlations of the expression levels of key BER pathway proteins with clinicopathological characteristics,including gender,age,smoking history,tumor location,Ki67 index,or TNM stage(a

关 键 词：小细胞肺癌 碱基切除修复 预后 肿瘤免疫微环境 

分 类 号：R394.2[医药卫生—医学遗传学] R73-362[医药卫生—基础医学] R734.2