BACKGROUND: Psoriasis is a systemic inflammatory skin disease. MicroRNAs (miRNAs) are a class of small non-coding RNA molecules that recently have been found in the blood to be relevant as disease biomarkers.

OBJECTIVE: We aimed to explore miRNAs potential as blood biomarkers for psoriasis.

METHODS: Using microarray and quantitative real-time PCR we measured the global miRNA expression in whole blood, plasma and peripheral blood mononuclear cells (PBMCs) from patients with psoriasis and healthy controls.

RESULTS: We identified several deregulated miRNAs in the blood from patients with psoriasis including miR-223 and miR-143 which were found to be significantly upregulated in the PBMCs from patients with psoriasis compared with healthy controls (FCH=1.63, P<0.01; FCH=2.18, P<0.01, respectively). In addition, miR-223 and miR-143 significantly correlated with the PASIscore (r=0.46, P<0.05; r=0.55, P<0.02, respectively). Receiver-operating characteristic analysis (ROC) showed that miR-223 and -143 have the potential to distinguish between psoriasis and healthy controls (miR-223: area under the curve (AUC)=0.80, miR-143: AUC=0.75). Interestingly, after 3-5 weeks of treatment with methotrexate following a significant decrease in psoriasis severity, miR-223 and miR-143 were significantly downregulated in the PBMCs from patients with psoriasis.

CONCLUSION: We suggest that changes in the miR-223 and miR-143 expressions in PBMCs from patients with psoriasis may serve as novel biomarkers for disease activity in psoriasis; however, further investigations are warranted to clarify their specific roles.