STEAP4 and arthritic joint disease: Indeed, several reports suggest that STAMP2 has a role in the pathogenesis of arthritis, as STAMP2 expression in the synovia correlates with the progression of joint swelling in both murine models and arthritis patients.38,39 Moreover, STAMP2-knockout mice spontaneously develop destructive arthritis.40 In this study, we first demonstrated that STAMP2 helped protect articular chondrocytes against FFA-induced lipoapoptosis.