Altered expression of miR-21, miR-125b, and miR-203 indicates a role for these microRNAs in oral lichen planus

BACKGROUND: Oral lichen planus (OLP), which is a chronic inflammatory disease of the oral mucosa with unknown etiology, affects about 2% of the population. MicroRNAs are small non-coding RNAs involved in normal processes such as development and differentiation as well as progression of human diseases. The aim of this study was to investigate the expression of miR-21, miR-125b, and miR-203 and to compare RNA levels of their potential targets, the tumor suppressor p53 and its relative p63, both known to be deregulated in OLP. METHODS: In biopsies from 20 patients with OLP and 20 age- and sex-matched healthy controls, epithelium was laser dissected and analyzed for the expression of miR-21, miR-125b, miR-203, p53, and p63 using qRT/PCR. RESULTS: Increased expression of miR-21 and miR-203, decreased expression of miR-125, and down-regulation of p53 and Delta Np63 RNA were seen in OLP compared to normal oral mucosa. When comparing microRNA expression to levels of p53 and p63 RNA, a significant negative correlation was seen between DNp63 and miR-203 and between miR-21 and p53, respectively. CONCLUSION: Results indicate a role for the studied microRNAs in changes seen in OLP. J Oral Pathol Med (2012) 41: 9095