Identification  of Significant Genes with poor prognosis in Liver Metastasis of Colorectal Cancer via Bioinformatical Analysis

Abstract

Background: Colorectal cancer (CRC) is a common malignant tumor in the world wild, and more than 50% patients have liver metastases. Purpose: The purpose of this study is to identify significant genes with poor outcome and the underlying mechanisms of CRC liver metastases. Methods: Gene expression profiles of GSE50760, GSE41568 and GSE14297 are available on website of GEO database. Differentially expressed genes (DEGs) between CRC liver metastases and primary tissues were picked out by GEO2R tool and Venn diagram software. The Database for Annotation, Visualization and Integrated Discovery (DAVID) was used to analyze Kyoto Encyclopedia of Gene and Genome (KEGG) pathway and gene ontology (GO). Then protein-protein interaction (PPI) of these DEGs was visualized by Cytoscape with Search Tool for the Retrieval of Interacting Genes (STRING). Results: There were total of 147 consistently expressed genes in the three datasets, including 123 up-regulated genes and 24 down-regulated genes enriched in complement and coagulation cascades, drug metabolism-cytochrome P450, metabolism of xenobiotics by cytochrome P450, prion diseases, chemical carcinogenesis, staphylococcus aureus infection and linoleic acid metabolism. Of PPI network analyzed by Molecular Complex Detection (MCODE) plug-in, all 39 genes were selected. Moreover, for the analysis of CRC survival among those genes, Kaplan–Meier analysis was implemented and 4 (SERPING1 ITIH2 CDH2 APOE) of 39 genes had a significantly worse prognosis. Conclusion: we have identified four significant DEGs with poor prognosis in CRC liver metastases on the basis of integrated bioinformatical methods, which could be potential therapeutic targets for CRC patients with liver metastases.