基于TCGA数据库分析乳腺癌组织RBP7 mRNA表达与肿瘤免疫细胞浸润及预后的相关性

Correlation of RBP7 mRNA Expression in Breast Cancer Tissues with Tumor Immune Cell Infiltration and Prognosis Based on TCGA Database

目的通过生物信息学的方法探讨视黄醇结合蛋白7(retinol binding protein 7,RBP7)在乳腺癌中的作用。方法使用R语言基于癌症基因组图谱(the cancer genome atlas,TCGA)数据库和人类蛋白质图谱(the human protein atlas,HPA)数据库探索基因RBP7在乳腺癌组织中的差异表达。通过Kaplan-Meier生存分析和受试者工作特征(receiver operating characteristic,ROC)曲线,评估RBP7与乳腺癌临床数据的关系。基于TCGA数据库分析RBP7高低表达分组与不同肿瘤浸润免疫细胞(tumor-infiltrating immune cells,TIICs)的相关性。基因组富集分析(gene set enrichment analysis,GSEA)评估RBP7在与表型相关度排序的基因表中的分布趋势。结果与癌旁组织相比,乳腺癌中RBP7 mRNA表达水平下调,该分子表达在细胞核中。ROC曲线分析显示RBP7诊断乳腺癌的曲线下面积(area under curve,AUC)是0.943(95%CI:0.926~0.960),RBP7的最佳截断值是6.29,敏感度和特异度分别为82.32%,93.69%。Kaplan-Meier生存分析显示RBP7低表达与乳腺癌患者的总生存率相关(HR=0.68,95%CI:0.49~0.93,P=0.017),RBP7是乳腺癌发生的独立危险因素。Spearman相关性揭示RBP7与乳腺癌中pDC细胞和NK细胞呈正相关(r=0.290,0.253,均P<0.05),与Th2细胞呈负相关(r=-0.217,P<0.05)。GSEA表明RBP7富集在脂肪生成、核糖体、肽配体结合受体、钙信号途径等通路中(均P<0.001)。结论RBP7影响乳腺癌的发生发展,可能成为乳腺癌潜在生物标志物和治疗靶点。

Objective To explore the role of retinol binding protein 7(RBP7)in breast cancer by bioinformatics.Methods R sofrware was used to explore the differential expression of the RBP7 gene in breast cancer by the cancer genome atlas(TCGA)dataset and the human protein atlas(HPA).Relationship between RBP7 and clinical data of breast cancer was evaluated by Kaplan-Meier survival analysis and receiver operating characteristic(ROC)curves.Correlation between high and low RBP7 expression groups and different tumor-infiltrating immune cells(TIICs)were analyzed based on the TCGA database.Gene set enrichment analysis(GSEA)was used to assess the distribute trends of RBP7 in gene tables sorted by phenotypic relatedness.Results RBP7 mRNA expression levels were down-regulated in breast cancer compared to paracancerous tissues,which were expressed in the nucleus.ROC curve analysis showed that the area under curve(AUC)of RBP7 for the diagnosis of breast cancer was 0.943(95%CI:0.926~0.960),and the best cut-off value of RBP7 was 6.29,with a sensitivity and specificity of 82.32%and 93.69%,respectively.Kaplan-Meier survival analysis showed that low expression of RBP7 was associated with overall survival rate in breast cancer patients(HR=0.68,95%CI:0.49~0.93,P=0.017),indicating that RBP7 was an independent risk factor for breast cancer.Spearman correlation showed that RBP7 was positively associated with pDC cells and NK cells(r=0.290,0.253,all P<0.05),and negatively associated with Th2 cells(r=-0.217,P<0.05)in breast cancer.GSEA showed that RBP7 was enriched in pathways such as adipogenesis,ribosome,peptiden ligand binding receptors,and calcium signaling pathway(all P<0.001).Conclusion RBP7 affects the occurrence and development of breast cancer,which may be a potential biomarker and therapeutic target for breast cancer.