Co-expression Network Analysis Identified COL8A1 Is Associated with the Progression and Prognosis in Human Colon Adenocarcinoma

Human colon adenocarcinoma is one of the major causes of tumor-induced death worldwide. A complicated gene interconnection network significantly regulates its progression and prognosis. The aim of our study was to find hub genes associated with the progression and prognosis of colon adenocarcinoma and to illustrate the underlying mechanisms. A weighted gene co-expression network analysis was performed in our study to identify significant gene modules and hub genes associated with the TNM stage of colon adenocarcinoma (n = 441). In the turquoise module of interest, 23 hub genes were initially selected, and 10 of them were identified as real hub genes with high connectivity in the protein-protein interaction network. In the terms of validation, COL8A1 had the highest correlation with clinical traits among all of the hub genes. Data obtained from the Oncomine and GEPIA databases showed a higher expression of COL8A1 in colon adenocarcinoma tissues compared with normal colon tissues. Kaplan-Meier survival curves showed that higher expression of COL8A1 resulted in a shorter overall survival time and disease-free survival time. Univariate and multivariate Cox proportional hazards analyses indicated that the COL8A1 expression was an independent prognostic factor for survival in colon adenocarcinoma patients. Finally, gene set enrichment analysis indicated that the gene sets associated with focal adhesion were significantly enriched in colon adenocarcinoma samples with COL8A1 highly expressed. COL8A1 was identified and proved to be correlated with the progression and prognosis of human colon adenocarcinoma, probably through regulating focal adhesion-related pathways.