The potential role of microRNAs as biomarkers in atopic dermatitis: a systematic review.

OBJECTIVE Reliable biomarkers are required for clinical use in atopic dermatitis (AD). MicroRNAs are mediators of post-transcriptional gene silencing, and specific expression patterns are being characterized in AD. To assess whether microRNAs could be useful biomarkers for clinical use in patients with AD. MATERIALS AND METHODS Systematic review of all articles identified in SCOPUS and PubMed through the PRISMA statement. Literature was summarized in narrative form and results are presented per category. RESULTS From a total of 118 identified references 11 manuscripts were included for qualitative analysis, after selecting them according to the eligibility criteria. An aberrant expression of microRNAs characterizes AD, which facilitates T cell polarization towards a Th17 phenotype, especially miR-155. There is also altered regulation of Th1/Th2 phenotypes by overexpression of miR-151a. The aberrant keratinocyte function observed in AD could also be due to altered expression of microRNAs, specifically miR-146a, miR-143 and miR-29. Finally, miR-203 may reflect the extent of inflammation in AD, in parallel with the tumor necrosis factor pathway and immunoglobulin E levels. CONCLUSIONS MicroRNAs are easily identifiable molecules in a variety of cells and body fluids that may be useful as diagnostic (miR-155 and miR-146a) and disease severity (miR-203) biomarkers in patients with AD.