Notably, PIK3R2 had lower expression in RA‐FLSs transfected with siRNA‐PIK3R2‐1 than that in PIK3R2‐2‐silenced RA‐FLSs, in view of this, siRNA‐PIK3R2‐1 was adopted for ensuing studies. This evidence concerns the gene PIK3R2 and rheumatoid arthritis.