CCL2 and rheumatoid arthritis: The DEGs which contributed to the pathway term “Rheumatoid arthritis” were CXCL8 (C-X-C Motif Chemokine Ligand 8), CTSL (Cathepsin L), CXCL2 (C-X-C Motif Chemokine Ligand 2), and CCL2 (C-C Motif Chemokine Ligand 2) (Figure 4B).