We confirmed the increased mRNA expression of fat mass and obesity-associated protein (FTO), the decreased mRNA expression of insulin-like growth factor 2 mRNA-binding protein 2 (IGF2BP2) and methyltransferase-like 14 (METTL14) in SMOC2-knockdown RA FLSs compared with RA FLSs transfected with control siRNA (Supplementary Fig. S5A–C). Here, IGF2 is linked to rheumatoid arthritis.