The evident overexpression of microRNA-203 in OLP was also described by Shen et al. (24) These authors (24) studied 50 oral biopsies of patients diagnosed with OLP and 19 healthy patients showing that the overexpression of microRNA-203 and the underexpression of microRNA-562 and its probable target, interleukin-22, molecule involved in chronic inflammation and autoimmunity (33), play an important role in the pathogenesis of OLP. This evidence concerns the gene IL22 and oral lichen planus.