MAPK8 and rheumatoid arthritis: Regarding the chemokine release, IL-27 induced CXCL9 and CXCL10 from control FLS, CCL2 and CXCL10 from RA-FLS and CXCL9 from RA-FLS was found to be mediated by PI3K and JNK pathways, JAK, PI3K and JNK pathways, and JAK and PI3K pathways, respectively (Figure 7).