Construction of an RNA Binding Protein-based Model for Prognosis Prediction of Colorectal Cancer

Abstract

Background: Colorectalcancer (CRC) is a prevalent gastrointestinal tumor with high incidence and mortality. Dysregulation of RNA binding proteins (RBPs) has been found in a variety of cancers and is related to oncogenesis and progression. This study aimed to develop and validate new biomarkers related to CRC prognosis by a series of bioinformatics analysis.Methods: We mined the gene expression data of 510 CRC samples from The Cancer Genome Atlas (TCGA) database, differentially expressed genes were screened and prognosis-related genes were identified. Furthermore, gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were carried out. A prognosis-related gene signature was constructed by univariate and multivariate Cox analysis. Kaplan–Meier curves and time-dependent receiver operating characteristic (ROC) curves were utilized to evaluate the signature,The test set was used to validate the RBPs risk score model.Survival analysis was carried out to determine the independent prognostic significance of the signature. A nomogram combined with the gene signature was constructed.Results: A total of 224 aberrantly expressed RBPs were obtained, comprising 78 downregulated and 146 upregulatedRBPs. 13 RBPs with p < 0.005 were revealed in univariateCox regression analysis of train group, then stepwise multivariate Cox regression was applied for constituting an eight- RBP (BRCA1, TERT, TDRD7, PPARGC1A, LUZP4, CELF4, ZC3H12C, PNLDC1) signature prognostic biomarkers. Further analysis demonstrated that high risk score for patients was significantly related to poor overall survival according to the model. The area under the time-dependent receiver operator characteristic curve of the prognostic model was 0.730 at 5 years. The signature-based risk score was an independent prognostic factor in CRC patients. We also established a nomogram based on eight RBPs and internal validation in the train set, which displayed a favorable discriminating ability for Colorectal cancer.Conclusions: The established eight-RBP signature may serve as a novel independent prognostic factor that could be an important tool to predict the prognostic outcome of CRC patients. However, the specific biological mechanism needs further verification.