The therapeutic effects of EIE-2, a novel 3-arylbenzofuran derivative, were evaluated in collagen-induced arthritis (CIA) rats and carrageenan-induced paw edema mice in vivo, as well as in LPS-, PMA- or TNF-α-stimulated human CD4+ T cells (Jurkat), human synovial sarcoma cells (SW982) and primary isolated lymphocytes in vitro. The gene discussed is CD4; the disease is synovial sarcoma.