Integrative Transcriptomics Analysis of Early-Onset and Late-Onset Colorectal Cancer

Abstract

Abstract Colorectal cancer (CRC) is the third most common type of cancer as it accounts for approximately 7% of all cancer types. The goal of this study is to identify and analyze the differentially expressed genes (DEGs) in early-onset CRC (EOCRC) and late-onset CRC (LOCRC). The RNA-seq data was downloaded from GEO database and analyzed using GEO2R tool. This was followed by gene and pathway enrichment, detection of protein-protein interactions, predicting the governing transcriptional factors. Besides, survival rate and response to chemotherapy were also assessed. 250 DEGs were obtained, 235 down-regulated and 15 up-regulated. Extracellular structure organization, collagen-containing extracellular matrix, platelet-derived growth factor and protein digestion and absorption were the most common biological process, cellular compartment, molecular function and KEGG pathway. Moreover, ten hub genes were filtered, namely COL1A1, VWF, COL3A1, EGF, IGF1, COL1A2, ITGB3, COL11A2, COL6A1, CD163 as the top-ten hub genes while FOXC1, GATA2, YY1, TFAP2A and PPARG were predicted to be the most significant transcriptional factors controlling them. Only EGF was considered as prognostic biomarker while COL1A1 as predictive biomarker. In conclusion, the shortlisted hub genes account for the discrimination between EOCRC and LOCRC which should be further explored in-depth.