基于ChIP-seq技术的肺癌细胞DNA碱基损伤热点全基因组分析  

Whole genomic hot spot analysis of DNA base damage in non-small cell lung cancer cells based on ChIP-seq technique

作　　者：李世勋 程燚[1] 戴楠[1] 熊艳丽[1] 李梦侠[1] LI Shixun;CHENG Yi;DAI Nan;XIONG Yanli;LI Mengxia(Department of Oncology,Daping Hospital,Army Medical University(Third Military Medical University),Chongqing,400042,China)

机构地区：[1]陆军军医大学(第三军医大学)大坪医院肿瘤科,重庆400042

出　　处：《第三军医大学学报》2021年第7期575-583,共9页Journal of Third Military Medical University

基　　金：国家自然科学基金面上项目(81871897)。

摘　　要：目的建立可用于在全基因组水平分析DNA碱基损伤位点分布的方法,利用该方法分析非小细胞肺癌A549细胞株中DNA碱基损伤热点区域的分布规律。方法利用染色质免疫沉淀偶联测序(chromatin immunoprecipitation sequencing, ChIP-seq)技术对A549细胞中与脱嘌呤/脱嘧啶核酸内切酶1(apurinic/apyrimidinic endonuclease 1, APE1)和8-氧鸟嘌呤DNA糖化酶1(8-oxoguanine DNA glycosylase 1, OGG1)蛋白特异结合DNA片段进行序列鉴定,通过生物信息学的方法分析全基因组DNA碱基损伤热点分布规律。结果 APE1和OGG1结合峰主要分布在基因启动子区,比例分别为41.70%和49.26%,APE1和OGG1结合峰于TSS上游2 000 bp区域内分别占比38.80%和39.80%,APE1与OGG1结合峰具有显著相关性(r=0.636 3,P<0.01)。APE1和OGG1共同结合峰相关基因数有25 038个,其中与肿瘤发生直接相关的有641个。结论建立在全基因组水平分析DNA碱基损伤位点分布的方法;在非小细胞肺癌细胞中,DNA碱基损伤并非随机分布而主要分布于基因调控功能区,碱基损伤修复蛋白结合相关热点区域与肿瘤发生及肿瘤炎症微环境密切相关。Objective To establish a method that can be used to analyze the distribution of DNA base damage sites at the genome-wide level, and use this method to analyze the distribution pattern of DNA base damage hotspots in non-small cell lung cancer cell line A549. Methods Chromatin immunoprecipitation sequencing(ChIP-seq)was used to perform immunoaffinity separation of specific binding DNA fragments with apurinic/apyrimidinic endonuclease 1(APE1)and 8-oxoguanine DNA glycosylase 1(OGG1)in A549 cells for sequence identification, and bioinformatics analysis was carried out to study the whole genome DNA base damage hotspots distribution. Results The binding peaks of APE1 and OGG1 were mainly distributed in the gene promoter region, with proportions of 41.70% and 49.26% respectively. The peaks of APE1 and OGG1 located in the 2 000 bp region upstream of TSS, accounting for 38.80% and 39.80%, respectively. The binding peaks of APE1 and OGG1 were significantly correlated(r=0.636 3, P<0.01). The number of APE1 and OGG1 associated genes with the same binding peak was 25 038, among which 641 were directly associated with tumorigenesis. Conclusion A genome-wide analysis method is established to analyze the distribution of DNA base damage sites. DNA base damage is not randomly distributed in lung cancer cells, but mainly distributed in gene regulatory region. Hot spots related to base damage repair protein binding may be closely associated with tumor genesis and tumor inflammatory microenvironment.

关 键 词：染色质免疫沉淀偶联测序 非小细胞肺癌 DNA碱基损伤 碱基切除修复 

分 类 号：R394-33[医药卫生—医学遗传学] R394.3[医药卫生—基础医学]