Moreover, KEGG enrichment analysis showed that those differentially expressed genes in the two databases were all significantly enriched in some inflammation-associated pathways, such as cytokine–cytokine receptor interaction, chemokine signaling pathway, viral protein interaction with cytokine and cytokine receptor, and IL-17 signaling pathway (Figures 2I,J), which were in accordance with inflammatory attributes of RA. This evidence concerns the gene IL17A and rheumatoid arthritis.