基于生物信息学分析POSTN基因在胃癌中的表达及免疫意义

Expression and immunological significance of POSTN gene in gastric cancer based on bioinformatics analysis

目的:探讨骨膜蛋白(POSTN)在胃癌免疫和预后中的价值。方法:利用生物信息学方法分析POSTN在胃癌中的表达及其与胃癌患者生存预后的关系。比较TCGA胃癌队列中癌组织和正常组织中的免疫细胞分布。从TISIDB数据库提取POSTN相关免疫调节剂,并通过GO和KEGG通路富集分析POSTN相关免疫事件。基于POSTN相关免疫调节剂,采用Cox回归开发一个多基因风险预测模型,由此产生风险评分。使用受试者工作特征曲线评估模型的预测准确性。构建带有校准曲线的预后诺模图预测个体五年生存率。结果:POSTN在胃癌组织中的表达明显高于非肿瘤组织。POSTN高表达组总生存期比POSTN低表达组缩短。POSTN高表达与多数免疫细胞高免疫浸润水平呈正相关。基于46个POSTN相关免疫调节剂进行的KEGG路径分析显示,NF-κB信号通路和细胞黏附分子参与其中。风险评分可作为胃癌患者预后的独立预测因子。结论:POSTN在胃癌组织中高表达,其表达与胃癌患者总体生存相关。POSTN与肿瘤免疫浸润相关,提示POSTN可能是胃癌的潜在免疫治疗靶点。

Objective:To investigate value of periostin(POSTN)in immunity and prognosis of gastric cancer.Methods:POSTN expression in gastric cancer and its relationship with survival and prognosis were analyzed by bioinformatics methods.Distribution of immune cells in cancer and normal tissues in TCGA gastric cancer cohort were compared.POSTN-related immunomodulators were extracted from TISIDB database,and POSTN-related immune events were analyzed by GO and KEGG pathway enrichments.Based on POSTN associated immunomodulators,a polygenic risk prediction model was developed by Cox regression,from which risk scores were generated.Prediction accuracy of the model was evaluated by subject operating characteristic curve.Prognostic normograms with calibration curves were constructed to predict 5-year survival probability of individuals.Results:POSTN expression in gastric cancer tissues was significantly higher than that in non-tumor tissues.Overall survival of POSTN high expression group was shorter than that of POSTN low expression group.High expression of POSTN was positively correlated with high level of immune infiltration in most immune cells.KEGG pathway analysis based on 46 POSTN-associated immunomodulators revealed involvement of NF-κB signaling and cell adhesion molecules.Risk score could be used as an independent predictor of prognosis in patients with gastric cancer.Conclusion:POSTN is highly expressed in gastric cancer tissues,whose expression is correlated with overall survival of gastric cancer patients.POSTN is associated with tumor immune invasion,suggesting that POSTN may be a potential immunotherapy target for gastric cancer.