TXNDC5 Contributes to Rheumatoid Arthritis by Down-regulating IGFBP1 Expression

Inhibiting TXNDC5 expression up‐regulates insulin‐like growth factor binding protein 1 (IGFBP1) level and down‐regulates IL‐6 secretion in RA synovial fibroblast‐like cells (RASFs). IGFBP1 has significantly decreased expression in rheumatic arthritis synovial tissues compared with samples of osteoarthritis. TXNDC5 expression stimulates RASF proliferation, migration and IL‐6 production by inhibiting IGFBP1 expression.