GO and KEGG Pathway Enrichment Analyses

GO annotates and classifies gene sets through biological pathways (BP), cellular components (CC), and molecular function (MF), while KEGG hints biological pathways related to DEGs (Ashburner et al., 2000; Wixon and Kell, 2000). Gene set enrichment analysis (GSEA) is a computational method that determines whether there is a significant difference between two groups for a defined set of genes. The DAVID online database provides a comprehensive set of functional annotation tools for annotation, visualization, and integrated discovery to understand the biological meaning of genes and proteins. GO and KEGG analysis in the present study was performed using (DAVID, http://david.ncifcrf.gov) (version 6.8) and GSEA software (version 3.0). The cut-off criterion was set as p < 0.05 and gene counts ≥ 5 (Huang et al., 2007).