In our previous study, we found the induction of MIF is mediated by p38 MAPK pathway when RA synovial fibroblasts are stimulated by conA, IFN-γ, CD40 ligand, IL-15, TGF-β, as well as IL-1β and TNF-α [41]. The gene discussed is TGFB1; the disease is rheumatoid arthritis.