Circ_0003972, circ-AFF2, circ_0003353, and circ_0088194 (Feng et al., 2022; Wen et al., 2022) are highly expressed in RA patients and fibroblast-like synoviocytes of rheumatoid arthritis (HFLS-RA) cells, circ_0008360, and circ_0130438 expressions were down-regulated. Here, AFF2 is linked to rheumatoid arthritis.