MicroRNAs (miRNAs) are small noncoding RNA molecules that negatively regulate 
gene expression at the post-transcriptional level. Currently, there are 939 
mature human miRNA sequences listed in the Sanger updated miRNA registry. There 
are approximately 1500 predicted miRNAs in the human genome that may regulate 
the expression of one third of our genes. By controlling the accumulation of the 
target protein(s) in cells, these regulatory RNA molecules participate in key 
functions in many physiological networks and their deregulation has been 
implicated in the pathogenesis of serious human disorders, such as cancer and 
infection. The implication of miRNAs in immune-mediated disorders such as 
rheumatoid arthritis (RA) has recently emerged suggesting that miRNA-based 
therapeutic approaches may have a promising potential in these diseases. Here, 
we provide an overview of the state-of-the-art on miRNAs in RA, focusing on both 
systemic and local features of the pathology.