This study aimed to construct prognostic model by screening prognostic miRNA signature of bladder cancer. The miRNA expression profile data of bladder cancer (BC) in The Cancer Genome Atlas (TCGA) were obtained and randomly divided into the training set and the validation set. Differentially expressed miRNAs (DEMs) between BC and normal control samples in the training set were firstly identified, and DEMs related to prognosis were screened by Cox Regression analysis. Then, the MiR Score system was constructed using X-Tile based cutoff points and verified in the validation set. The prognostic clinical factors are selected out by univariate and multivariate Cox Regression analysis. Finally, the mRNAs related to prognosis were screened and the biological pathway analysis was carried out. We identified the 7-miRNA signature was significantly associated with the patient’s Overall Survival (OS). A prognostic model was constructed based on the prognostic 7-miRNA signature, and possessed a relative satisfying predicted ability both in the training set and validation set. In addition, univariate and multivariate Cox Regression analysis showed that age, lymphovascular invasion and MiR Score were considered as independent prognostic factors in BC patients. Furthermore, based on MiR Score prognostic model, several differentially expressed genes (DEGs), such as WISP3 and UNC5C, as well as their related biological pathway(s), including cell–cell adhesion and neuroactive ligand-receptor interaction, were considered to be related to BC prognosis. The prognostic model which was constructed based on the prognostic 7-miRNA signature presented a high predictive ability for BC.

中文翻译：

---

基于miRNA表达谱的《癌症基因组图谱》中潜在的膀胱癌预后模型

本研究旨在通过筛选膀胱癌的预后miRNA信号来构建预后模型。获得了《癌症基因组图谱》（TCGA）中膀胱癌（BC）的miRNA表达谱数据，并将其随机分为训练集和验证集。首先鉴定出训练组中BC和正常对照样品之间差异表达的miRNA（DEM），并通过Cox回归分析筛选与预后相关的DEM。然后，使用基于X-Tile的截止点构建MiR评分系统，并在验证集中进行验证。通过单因素和多因素Cox回归分析选择预后的临床因素。最后，筛选与预后相关的mRNA，并进行生物学途径分析。我们确定7-miRNA签名与患者的总体生存率（OS）显着相关。基于预后的7-miRNA标记构建了预后模型，并且在训练集和验证集中均具有相对令人满意的预测能力。此外，单因素和多因素Cox回归分析表明，年龄，淋巴管浸润和MiR评分被认为是BC患者的独立预后因素。此外，基于MiR成绩预测模型，认为WISP3和UNC5C等几种差异表达基因（DEG）及其相关的生物途径包括细胞间粘附和神经活性配体-受体相互作用。与BC预后有关。