【作者】 李梨；

【导师】 张大志；

【作者基本信息】 重庆医科大学 ， 临床医学（专业学位）， 2021， 硕士

【摘要】 背景与目的C9基因是一种蛋白质编码基因,相关研究表明它可能是一种潜在的肿瘤生物标志物。然而,C9基因在肝细胞癌中的表达及其作用机制的研究鲜有报道。本研究通过对公共数据库的数据挖掘及实验验证确定了C9基因在肝细胞癌中的表达水平,分析了C9基因表达与肝细胞癌预后的相关性,通过生物信息学分析及其邻近lnc-RNA的研究推测C9基因在肝细胞癌中的分子机制,为肝细胞癌的诊断和靶向治疗提供了新的思路。方法本研究通过分析GEO数据库中m RNA微阵列数据集,获得在肝细胞癌中差异表达的C9基因的表达谱数据,同时进行荟萃分析。收集13例患者的配对组织样本,使用RT-q PCR检测C9基因在肝细胞癌中的表达情况,结合免疫组化结果,进一步确定C9蛋白在肝癌中的表达水平。从TCGA数据库中获取的数据用于探讨C9基因表达水平与肝细胞癌患者的预后之间的相关性。此外,本研究还构建了共表达基因网络,对C9基因的共表达基因进行生物信息学分析。利用RT-q PCR检测lnc-C9在肝细胞癌中的表达情况,进一步研究C9基因在肝细胞癌中的分子机制。结果从GEO数据库中获取的数据集的荟萃分析结果显示,C9基因在肝细胞癌组织中的表达低于正常肝组织(SMD=-1.79,95%CI=-2.01,-1.58,P=0.00)。RT-q PCR的结果证实肝细胞中C9基因(P<0.01)和Lnc-C9(P=0.0215)表达下调。免疫组化进一步证实C9蛋白在肝细胞癌组织中表达水平较癌旁组织更低。TCGA数据分析结果显示,C9基因的表达与患者性别、T分期、肿瘤分期高度相关(P=0.01276,P=0.00593,P=0.00704)。生物信息学分析共共获取130个C9基因的共表达基因,这些共表达基因在代谢途径、补体和凝血级联等关键途径中高度富集。结论公共数据库的数据分析及RT-q RCR实验结果显示,C9基因及C9蛋白在肝细胞癌组织中的表达低于正常组织,肿瘤切除或无远处转移的患者在C9基因表达下调时预后较差,C9基因的下调可能预示不良临床结局。Lnc-C9在肝癌中的表达水平与C9基因呈正相关,生物信息学分析为研究肝细胞癌发生发展的机制提供新的思路。更多还原

【Abstract】 Background and ObjectiveC9 gene was a protein-coding gene.Relating studies had shown that the gene may be a potential tumor biomarker.However,There was no report about the expression and mechanism of C9 gene in HCC at present.This study confirmed the expression level of C9 gene in HCC through data mining of public database and experimental verification,analyzed the correlation between C9 gene expression and prognosis of HCC.Then,This research speculated the molecular mechanism of C9 gene in HCC through bioinformatics analysis and its adjacent Lnc-RNA research,to provide new ideas for the diagnosis and targeted therapy of HCC.MethodIn this study,we analyzed the m RNA microarray data set of GEO database to obtain the expression profile data of C9 gene differentially expressed in HCC,and conducted a meta-analysis.RT-q PCR was used to detect the expression of C9 gene in HCC.Combined with the results of immunohistochemistry,the expression level of C9 protein in HCC was further determined.The data obtained from TCGA database were used to explore the correlation between C9 gene expression level and prognosis of patients with HCC.In addition,a co-expression gene network was constructed to analyze the co expression genes of C9 gene.RT q PCR was used to detect the expression of lnc-c9 in HCC,and to further study the molecular mechanism of C9 gene in HCC.ResultAs the meta-analysis of data set obtaining from the GEO database shown,the expression of C9 gene in hepatocellular carcinoma tissue was lower than the normal liver tissue(SMD=-1.79,95%CI=-2.01,-1.58,P=0.00).The result of RT-q PCR verified the C9 gene in hepatocellular carcinoma(P<0.01)and the expression of Lnc-C9(P=0.0215)decreased.Immunohistochemistry further confirmed that the expression level of C9 protein in HCC was lower than that in adjacent tissues.TCGA data analysis showed that the expression of C9 gene was highly correlated with gender,T stage and tumor stage(P=0.01276,P=0.00593,P=0.00704).A total of130 co-expressed genes of C9 genes were obtained by bioinformatics analysis.These co-expressed genes were highly enriched in key pathways such as metabolic pathways,complement and coagulation cascade.ConclusionData analysis of public database and RT-q PCR results showed that the expression of C9 gene and C9 protein in HCC tissues was lower than that in normal tissues.Patients with tumor resection or without distant metastasis had poor prognosis when the expression of C9 gene was down regulated.The down regulation of C9 gene may predict adverse clinical outcomes.The expression level of lnc-c9 in HCC is positively correlated with C9 gene.Bioinformatics analysis provides a new way to study the mechanism of occurrence and development of HCC.更多还原