POS0191 THE VALUE OF MIR-20B, MIR-22, MIR-26A, MIR-125B AND MIR-221 IN RHEUMATOID ARTHRITIS

Abstract

Background:Micro-RNAs (miRNAs) are an endogenous small, single-stranded, non-coding RNAs with a 18-25 nucleotide long and have been reported as a potential extracellular biomarkers of various diseases. They mainly decrease the gene expression by inhibiting the translation or cause mRNA destabilization.Objectives:The aim of the study was to identify miRNAs whose plasma expression level is associated with RA prevalence and/or activity.Methods:A total of 74 unrelated individuals, 50 with RA and 24 in a control group were enrolled to the study. Real-time PCR was used to evaluate the plasma expression levels of 5 miRNAs: miR-20b, miR-22 miR-26a, miR-125b, miR-221.Results:We found the differences in four out of five evaluated miRs between RA and HC group – miR-26a, p<0.0001; miR-125b, p <0.0001; miR-20b p<0.0001; miR-22, p=0.005. Graphical presentation of the results is shown in Figure 1. The logistic regression results showed that miR-22 (p=0.0003) and miR-26a (p=0.049) are the most important molecules distinguishing RA patients and healthy controls in the study. MiR-22 was positively correlated with ESR (rs=0.41), CRP (rs=0.49) and DAS28 (rs=0.33) and miR-26a was positively correlated with ESR (rs=0.49), CRP (rs=0.41), number of swelling joints (rs=0.43), number of painful joints (rs=0.74) and DAS28 (rs=0.63). Moreover, miR-22 expression was different between rheumatoid factor (RF) positive and RF negative patients (p=0.04).Conclusion:The results showed that miR-22 (p=0.0003) and miR-26a (p=0.049) may be the most useful in evaluated panel of miRs distinguishing RA patients and HCs. In this study we demonstrated for the first time that plasma concentration of miR-22 may be considered as a potential molecular marker of RA exacerbation.