In the active RA patients, decreased expression of miR-146a (targeting the signal transducer and activator transcription 1 [STAT1]) resulted in development of a pro-inflammatory phenotype in Treg cells.27 Hence, miR-146a in RA patients promotes a pro-inflammatory phenotype of Treg cells and contributes to the pathogenesis of RA. This evidence concerns the gene STAT1 and rheumatoid arthritis.