However, LERFS was low expressed in RA FLSs, and the reduced LERFS led to the reduction of LERFS-hnRNP Q complex, thereby reducing the binding of hnRNP Q to the mRNAs of small GTPase protein RhoA, Rac1 and CDC42 that control the activity and proliferation of FLSs. This evidence concerns the gene LERFS and rheumatoid arthritis.