肺腺癌癌旁基因组异常情况分析及初步功能研究

发布时间：2018-03-26 14:18

  本文选题：肺癌　切入点：癌旁组织　出处：《中国科学技术大学》2016年硕士论文

【摘要】：肺癌作为全世界发病率最高和致死人数最多的癌症,发病原因包括吸烟、职业暴露、空气污染和基因突变等,2015年中国肿瘤登记年报显示,肺癌仍居中国发病率的首位。半个多世纪以来全世界在肺癌的手术、放疗、化疗及靶向治疗方面取得了巨大的进展和成绩,但由于缺乏有效的早期诊断方法且肺癌患者出现症状时多为晚期,因而总的5年存活率不到15%。基因突变作为肺癌发生的诱因之一,突变率随着环境污染的加剧而不断提高,细胞癌变的概率也随之增加。肺癌的特点之一是具有异质性,对基因突变的分析对于揭示肺癌发生发展有重要作用,随着肺癌测序技术的快速发展,越来越多的突变基因被发现,其中包括EGFR、KRAS等一些肺癌发生中重要的驱动突变,为肺癌的早期诊断和靶向治疗提供了新的方向。与肿瘤组织一样,肿瘤的正常对照组织也同样暴露在烟草等环境致癌物中,为了研究这些组织基因组在环境致癌物中发生的变化,我们从TCGA数据库下载了513例肺腺癌病人的全外显子数据,筛选出癌旁特有的基因组异常点并过滤掉体细胞突变,统计突变特征并对病人进行生存分析后绘制病人生存曲线,然后选取癌旁组织突变与病人预后相关的基因进行初步的功能研究。在癌旁组织突变基因中,外显子突变频率为0.93/Mb,碱基突变以C：GT：A的置换为主,有29个基因突变率大于3%,其中ZNF511和TMEM184A与预后成正相关,其中ZNF511在513例病人中有16例癌旁发生突变且该基因存在三种突变情况,突变的结果是蛋白质产物的缩短或延长,癌旁中ZNF511发生突变与病人的预后是成正相关的。然而目前对于ZNF511基因功能还尚未有研究,因此我们想通过基因的过表达和干扰对ZNF511进行初步的功能研究。因此我们对ZNF511瞬时转染同时构建慢病毒稳转株,设计并合成了小RNA干扰序列在肺腺癌细胞系A549细胞中进行干扰,初步显示敲低ZNF511后对细胞增殖能力有一定抑制作用,且可以引起pAKT的下调。总之,本文对肺腺癌中正常的对照组织基因组变异情况进行了系统的分析并对ZNF511基因功能做了初步研究,为肺癌发生发展的机理提供了全新的思路。
[Abstract]:Lung cancer has the highest incidence and the highest number of deaths in the world. The causes of lung cancer include smoking, occupational exposure, air pollution and gene mutation, according to the 2015 China Cancer Registry Annual report. Lung cancer still ranks first in China. Over the past half century, the world has made great progress and achievements in surgery, radiotherapy, chemotherapy and targeted treatment of lung cancer. However, due to the lack of effective early diagnosis methods and the late stage of lung cancer, the total 5-year survival rate is less than 15%. Gene mutation is one of the inducements of lung cancer, and the mutation rate increases with the increase of environmental pollution. One of the characteristics of lung cancer is its heterogeneity. The analysis of gene mutation plays an important role in revealing the occurrence and development of lung cancer, and with the rapid development of lung cancer sequencing technology, More and more mutant genes have been found, including some important driving mutations in the carcinogenesis of lung cancer, such as EGFRX KRAS, which provide a new direction for early diagnosis and targeted treatment of lung cancer. The normal control tissue of the tumor was also exposed to environmental carcinogens such as tobacco. In order to study the changes of these tissue genomes in environmental carcinogens, we downloaded the total exon data from 513 patients with lung adenocarcinoma from the TCGA database. Screening out specific genomic anomalies beside cancer, filtering out somatic mutations, counting mutation characteristics, and making survival analysis of patients and drawing patient survival curves. The mutation frequency of exon in paracancerous tissue mutation was 0.93Mb, and the base mutation was mainly C:GT:A replacement. The mutation rate of 29 genes was more than 3, in which ZNF511 and TMEM184A were positively correlated with prognosis. ZNF511 mutation occurred in 16 out of 513 patients and there were three mutations in the gene. The result of mutation was the shortening or prolongation of protein products. There is a positive correlation between the mutation of ZNF511 and the prognosis of patients with cancer. However, the function of ZNF511 gene has not been studied yet. Therefore, we want to study the function of ZNF511 by gene overexpression and interference. Therefore, we constructed a stable lentivirus strain by transient transfection of ZNF511 and designed and synthesized a small RNA interference sequence for interference in lung adenocarcinoma cell line A549. Preliminary results show that ZNF511 knockout has a certain inhibitory effect on cell proliferation, and can cause down-regulation of pAKT. In this paper, the genomic variation of normal control tissues in lung adenocarcinoma was systematically analyzed, and the function of ZNF511 gene was preliminarily studied, which provided a new idea for the pathogenesis of lung cancer.
【学位授予单位】：中国科学技术大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：R734.2
，

本文编号：1668206