Identification Of Key Genes And Pathways In Radioresistant Colorectal Cancer Using Bioinformatics Analysis

Background: Colorectal cancer(CRC)is one of the most malignant tumor worldwide.Radiotherapy is an integral part of the strategies for CRC,but the mechanism of radio resistance in CRC is still unclear.The aim of the present study was to identify key genes and pathways involved in the radio resistance of CRC by using bioinformatics.Methods: The microarray dataset GSE97543 was downloaded from the Gene Expression Omnibus(GEO)database,and 12 samples are compared in total.There are 3 replicates for each condition.Conditions are: 1.SW1463.2.SW1463 radiation resistant.3.SW1463 +4Gy.4.SW1463 radiation resistant + 4Gy.Using acquired differentially expressed genes(DEGs),functional and pathway enrichment analysis were performed by using the FUNRICH database,and the protein–protein interaction(PPI)network was established by the Cytoscape software.Results: 734 upregulated and 543 downregulated DEGs were found in SW1463 samples after radiation.101 genes were upregulated and 209 were downregulated between radio resistance samples and SW1463 samples.219 genes upregulated and 101 downregulated in radio resistance samples after radiation.704 DEGs were upregulated in SW1463 samples and not upregulated in radio resistant samples after radiation.537 DEGs were downregulated in SW1463 samples and not downregulated in radio resistant samples after radiation.209 DEGs were upregulated in radio resistant samples and not upregulated in SW1463 samples after radiation.94 DEGs downregulated in radio resistant samples and not downregulated in SW1463 samples after radiation.The gene ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment analysis from FUNRICH showed that the DEGs were mainly enriched in PPAR signaling pathway,Cell cycle signaling pathway and PI3K-Akt signaling pathway.DEGs were identified from the PPI networkConclusions: Genes and pathways related to apoptosis,cell cycle and DNA damage and repair may play a crucial role in CRC radio sensibility and radio resistance,whereas those DEGs may be key factors in the therapy of CRC.