MYH9 and rheumatoid arthritis: Functional experiments demonstrated that MYH9 promoted migration and invasion of RA-FLSs in vitro and in a humanised synovitis model, which was substantially inhibited by blebbistatin, a specific MYH9 inhibitor.<h4>Conclusions</h4>This study provides a comprehensive resource of the RA-FLS-derived secretome and suggests that MYH9 represents a promising target for retarding abnormal migration and invasion of RA-FLSs.