Identification of Hub Genes Associated With Progression and Prognosis of Bladder Cancer by Integrated Bioinformatics Analysis.
Abstract Background: Bladder cancer (BLCA) is the most popular malignant carcinomas in genitourinary system which has a high incidence and is prone to relapse. However, the molecular mechanism of BLCA remains to be unclear. Moreover, there is still a shortage of effective biomarkers that can predict progression and prognosis of BLCA. The objective of current study is to screen significant genes as biomarkers to forecast the progression and prognosis of BLCA patients.Methods: Gene expression profile downloaded from TCGA database and GEO database was used. Differential gene expression analysis and WGCNA were conducted to identify differential co-expression genes. In addition, GO enrichment analysis and KEGG pathway analysis were used to explore the functions of these genes. Moreover, PPI network, OS and DFS were used to identify survival-related hub genes. Finally, the expression levels of these genes were validated by qRT-PCR and HPA database.Results: About 124 differential co-expression genes were identified. And these genes were mainly enriched in muscle system process and muscle contraction (BP), contractile fiber, myofibril, sarcomere, focal adhesion and cell-substrate junction (CC) and actin binding (MF) in GO enrichment analysis, while enriched in vascular smooth muscle contraction, focal adhesion, cardiac muscle contraction, hypertrophic cardiomyopathy, dilated cardiomyopathy and regulation of actin cytoskeleton in KEGG analysis. Furthermore, five survival-related hub genes (MYH11, ACTA2, CALD1, TPM1, MYLK) were identified via overall OS and DFS. In addition, the expression levels of the five survival-related genes were upregulated with the procession of BLCA, such as grade, stage and TNM stage. Finally, all survival-related hub genes were found to be down-regulated in BLCA via qRT-PCR and HPA database.Conclusions: Our current study verified five new key genes in BLCA, which could help us better understand the pathogenesis of BLCA. And these five hub genes may be involved in the development and progression of BLCA and served as potential biomarkers.