BSG and rheumatoid arthritis: The possibility that treatment with cDMARDs, including MTX, was responsible for this discrepancy was ruled out, since our RA patients that were all treated with MTX or other cDMARDs showed no difference in their levels of endostatin, CD147, or proteasome 20S activity compared to those of untreated RA patients with active disease from a different cohort (Figure S7).