PIAS1 and rheumatoid arthritis: In their study using a macrophage-like cell line, the authors demonstrated that SUMOylation of PPAR-γ is facilitated by PIAS1 and required for its ability to target nuclear receptor corepressor-histone deacetylase-3 complexes on the promoter of proinflammatory genes [85], implying targeting PIAS1 for rheumatoid arthritis treatment [82].