Identification of Prognostic Signature for Bladder Cancer Based on circRNA-Related Competing Endogenous RNA Network

Background: Recent studies describe that circular RNA (circRNA) plays an important role in the occurrence and development of bladder cancer (BC). Certain circRNAs can act as competitive endogenous RNAs (ceRNAs), which play the role of sponges for microRNAs (miRNAs) and participate in the post-transcriptional regulation of target genes. However, the comprehensive analysis of the circRNA-miRNA-mRNA ceRNA network in the prognosis of BC is rarely reported. Methods: We collected the expression data of circRNA, miRNA, mRNA and the clinicopathological data from GEO and TCGA databases. Then, the ceRNA network was established, and the functional enrichment analyses were performed. Subsequently, a prognostic signature was developed based on mRNAs in the ceRNA network. Furthermore, we established a prognostic nomogram based on the prognostic signature and clinical characterization. Findings: We identified 18 prognostic mRNAs, and divided the BC patients into high- and low-risk groups. There were significant differences in the overall survival (OS), and the receiver operating characteristic (ROC) curve indicated the satisfactory accuracy of the predictive signature. In addition, the calibration curves revealed the accuracy of the nomogram. Interpretation: Such a model based on prognostic mRNAs in the ceRNA network may help predict the mortality risk for individual BC patients. Funding Statement: This work was supported by the National Natural Science Foundation of China (81874137), the Outstanding Youth Foundation of Hunan Province (2018JJ1047), and the Hunan Province Graduate Research and Innovation Project (Grant/Award Number: 2019zzts197). Declaration of Interests: The authors declared no conflict of interest. Ethics Approval Statement: As this study used data obtained from the public databases, ethical approval was not required.