摘要
目的 探索SRPRB在肝细胞癌(hepatocellular carcinoma,HCC)患者中的表达水平及与预后的关系,并基于其共表达的免疫相关基因构建HCC临床预后风险模型.方法 本研究从TCGA数据库中获取HCC患者的表达谱和临床信息.采用Kaplan-Meier法、"pROC"包分析SRPRB与HCC患者生存预后的关系.实时荧光定量PCR及免疫组化验证SRPRB在HCC mRNA和蛋白水平表达情况.采用Spearman相关分析确定SRPRB的共表达基因,与ImmPort数据库获取的免疫相关基因取交集获得HCC患者SRPRB共表达免疫相关基因.并通过GO富集分析、KEGG通路分析确定这些基因参与的生物学过程及功能.将TCGA数据库中的患者按5∶5比例随机分为训练集和内部验证集,以GEO数据库中的HCC患者作为外部验证集.随后利用Cox回归筛选基因来构建预后模型,利用Kaplan-Meier生存曲线、ROC曲线评估风险模型对HCC的预测价值,并基于预测模型建立列线图.结果 SRPRB在HCC组织中的表达量显著高于正常组织,K-M曲线显示,高表达SRPRB的患者总生存率比低表达组差.功能富集分析显示,SRPRB共表达免疫相关基因主要参与受体配体活性、免疫受体活性、抗原处理和呈递、自然杀伤细胞介导的细胞毒性作用、Toll样受体信号通路等信号通路.单因素和多因素Cox回归分析共筛选出7个SRPRB相关免疫预后基因,构建包括七个基因(SLC29A3、IKBKE、ISG20L2、PSMD6、CXCL8、TEK、EED)的风险模型,Kaplan-Meier生存曲线表明,训练集、内部验证集和外部验证集中的高风险组患者预后更差(P＜0.01).训练集中1年、2年和3年AUC值分别为0.819、0.812和0.803、内部验证集中1年、2年和3年AUC值分别为0.739、0.623和0.692且外部验证集中1年、2年和3年AUC值分别为0.608、0.653和0.610.该模型可作为独立预测因素评估HCC患者的预后,基于风险评分构建的列线图具有更好的区分能力和一致性.结论 SRPRB高表达与HCC的不良预后有关,基于SRPRB共表达免疫相关基因构建的预后模型能较好地评估肝癌患者的预后情况.
Abstract
Objective To investigate the expression level of SRPRB in hepatocellular carcinoma(HCC)patients and its rela-tionship with prognosis,and to construct a clinical prognostic risk model for HCC based on its co-expressed immune-related genes.Methods In this study,expression profiles and clinical information of HCC patients were obtained from the TCGA database.The rela-tionship between SRPRB and survival prognosis of HCC patients was analysed using the Kaplan-Meier method and the"pROC"pack-age.Real-time fluorescence quantitative PCR and immunohistochemistry were used to verify the expression of SRPRB in HCC mRNA and protein levels.Spearman correlation analysis was used to identify the co-expressed genes of SRPRB,and intersected with the im-mune-related genes obtained from the ImmPort database to obtain the co-expressed immune-related genes of SRPRB in HCC patients.The biological processes and functions involved in these genes were also determined by GO enrichment analysis and KEGG pathway a-nalysis.The patients in the TCGA database were randomly divided into a training set and an internal validation set in a 5∶5 ratio,and the HCC patients in the GEO database were used as an external validation set.Then,Cox regression was used to screen the genes to construct the prognostic model,and the predictive value of the risk model for HCC was evaluated using Kaplan-Meier survival curves and ROC curves,and a column-line diagram was constructed based on the predictive model.Results The expression of SRPRB in HCC tissues was significantly higher than that in normal tissues,and the K-M curves showed that the overall survival rate of patients with high expression of SRPRB was worse than that of the low expression group.Functional enrichment analysis showed that SRPRB co-expressed immune-related genes were mainly involved in signaling pathways such as receptor ligand activity,immune receptor activity,antigen processing and presentation,natural killer cell-mediated cytotoxicity and Toll-like receptor signaling pathway.A total of seven SRPRB-associated immune prognostic genes were screened by univariate and mul-tivariate Cox regression analyses,and a risk model including seven genes(SLC29A3,IKBKE,ISG20L2,PSMD6,CXCL8,TEK and EED)was constructed,and the Kaplan-Meier survival curves showed that patients with high risk in the training set,internal validation set and external validation set had a worse prognosis group(P＜0.01).The 1-,2-,and 3-year AUC values were 0.819,0.812,and 0.803 in the training set,0.739,0.623,and 0.692 in the internal validation set,and 0.608,0.653,and 0.610 in the external vali-dation set.The model could be used as an independent predictor to assess the prognosis of HCC patients,and the column-line graphs constructed based on risk scores had better discriminative ability and consistency.Conclusion High SRPRB expression is associated with poor prognosis in HCC,and the prognostic model constructed on the basis of SRPRB co-expression of immune-related genes can better assess the prognosis of hepatocellular carcinoma patients.
维普
万方数据