Metastasis-inducing S100A4 protein is associated with treatment response in patients with recent-onset rheumatoid arthritis

Background/objectives There is increasing evidence that metastasis-inducing S100A4 protein may exert pro-inflammatory and destructive effects in rheumatoid arthritis (RA). The authors have previously demonstrated that S100A4 is significantly up-regulated in RA and correlates with disease activity. Therefore, the authors investigated the relationship between S100A4, disease activity and response to treatment with synthetic disease modifying antirheumatic drugs (DMARDs) in patients with recent-onset RA. Methods Serum levels of S100A4 protein were determined by ELISA before and after 3 months of initiation of the DMARD treatment in 59 patients with recent-onset RA (symptom duration