DNMT1 and rheumatoid arthritis: Previous research combining SAM with DIZE in the treatment of isolated synovial fibroblasts sourced from patients with rheumatoid arthritis (RA) or osteoarthritis (OA) resulted in elevations of 5-methylcytosine (5-MeC) and DNA methyltransferase 1 (DNMT-1), and reduced the adhesion and invasiveness of RA synovial fibroblasts (RASFs) in a mouse model.