基于生物信息学技术筛选长生存期胶质母细胞瘤预后相关基因的研究

发布时间：2018-02-28 20:21

本文关键词： GBM 生物信息学 Fibulin-4 IGFBP-2 CH3L1 预后　出处：《吉林大学》2017年硕士论文　论文类型：学位论文

【摘要】：背景:GBM是成人中枢神经系统最常见且是恶性程度最高的脑肿瘤,尽管采用包括手术切除、术后放射治疗以及替莫唑胺化疗的标准治疗方案,但大多数病人预后仍差。一小部分患者预后相对较好,中位生存期达到24个月或更长时间。研究发现GBM病人对各种治疗的敏感性以及预后情况受多种分子标记物的影响。寻找与GBM预后相关的因素对提高患者生存率有重大意义。生物信息技术可以对数据库中的大量微阵列数据进行同源性分析、相似性分析等等,使我们在全基因水平研究基因的调控,因此,生物信息技术的应用大大促进了医学基础研究的发展。目的:筛选GBM病人预后相关的基因,发现长生存期GBM患者的临床特点及肿瘤分子表达特征。提高对GBM患者的治疗效果,为预后评估提供依据。方法:首先,应用WebArrayDB对微阵列数据进行整合分析,我们筛选GEO数据库中GBM长生存期患者(LTSs)和短生存期患者(STSs)相关性最大的前100个基因,再同TCGA和REMBRANDT数据库的提供的候选基因进行对比分析,最终筛选出可评估患者预后的 3 个基因:Fibulin-4,IGFBP-2 和 CHI3L1。然后应用收集的77例GBM患者的石蜡包埋组织(FFPE)样本,提取DNA和RNA,应用甲基化特异性定量PCR技术(qMSP)检测肿瘤MGMT启动子甲基化状态,用实时荧光定量PCR(qPCR)来检测肿瘤中上述基因的表达。研究基因与患者预后相关性,为GBM预后的评估提供依据。结果:应用WebArrayDB对GEO数据库微阵列数据的整合分析,发现Fibulin-4,IGFBP-2和CHI3L1 3个基因与GBM患者的预后相关。在我们的实验中,LTS组MGMT启动子甲基化发生率为73.3%(11/15),STS组MGMT启动子甲基化发生率为38.7%(24/62)。两组之间有显著差异(p0.01)。GBM样本中3个基因的mRNA表达水平明显高于正常脑组织中(p0.01),且LTS组样本3个基因的表达水平明显低于STS组(p0.01),多因素分析显示Fibulin-4和IGFBP-2的表达与病人预后的相关性显著(P0.05)。Kaplan-Meier分析显示Fibulin-4和IGFBP-2和病人生存期密切相关(Fibulin-4 p0.01;IGFBP-2 p0.05)。结论:Fibulin-4和IGFBP2同GBM病人的预后密切相关,其表达情况可以作为评估患者预后的依据。
[Abstract]:Background: one of the most common and most malignant brain tumors in the adult central nervous system (CNS) is:: GBM, despite the use of standard treatments, including surgical resection, postoperative radiotherapy, and temozolidomide chemotherapy. But the prognosis of most patients is still poor. A small number of patients have a relatively good prognosis. The median survival time was 24 months or longer. The study found that the sensitivity and prognosis of patients with GBM were influenced by many molecular markers. Finding the factors related to the prognosis of GBM patients could improve the survival rate of the patients. Significant. Bioinformation technology allows for homology analysis of large amounts of microarray data in databases, Similarity analysis and so on make us study gene regulation at the whole gene level. Therefore, the application of bioinformatics has greatly promoted the development of basic medical research. The clinical features and tumor molecular expression of GBM patients with long survival period were found. The therapeutic effect of GBM patients was improved and the basis for prognosis evaluation was provided. Methods: firstly, microarray data were integrated and analyzed by WebArrayDB. We screened the top 100 genes with the greatest correlation between GBM long survival patients and short survival patients in GEO databases, and compared them with the candidate genes provided by TCGA and REMBRANDT databases. Finally, three genes, 1: Fibulin-4 IGFBP-2 and CHI3L1, were selected to evaluate the prognosis of patients. The paraffin embedded tissue samples of 77 patients with GBM were collected. DNA and RNAs were extracted, methylation-specific quantitative PCR technique was used to detect the methylation status of tumor MGMT promoter, and real-time fluorescence quantitative PCR was used to detect the expression of these genes. Results: WebArrayDB was used to analyze the microarray data of GEO database. In our experiment, the incidence of methylation of MGMT promoter was 73.33% and the incidence of methylation of MGMT promoter in MGMT group was 38.7% 24% 62%. There was a significant difference between the two groups (p0.01. GBM). The expression level of three genes in LTS group was significantly lower than that in STS group. Multivariate analysis showed that the expression of Fibulin-4 and IGFBP-2 was significantly correlated with the prognosis of patients. Kaplan-Meier analysis showed that Fibulin-4 and IGFBP-2 were significantly correlated with the prognosis of patients. Fibulin-4 p0.01 IGFBP-2 p0.05. Conclusion the prognosis of patients with GBM is closely related to the prognosis of patients with GBM. Its expression can be used as a basis for evaluating the prognosis of patients.
【学位授予单位】：吉林大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：R739.4

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