Serum miR-124a and miR-34a as Potential Biomarkers for Rheumatoid Arthritis

Abstract

Background: MicroRNAs (miRs) are defined as noncoding small RNAs that are involved in the regulation of various immune functions, indicating they could be possible biomarkers for immune-mediated disorders. We aimed to evaluate miR-124a and miR-34a levels in serum as diagnostic biomarkers for rheumatoid arthritis (RA) and to investigate their correlation with the disease activity in RA patients. Methods: Our study consisted of 40 patients with RA and 40 controls. The disease activity for the RA patients was evaluated using the Disease Activity Score in 28 joints (DAS28). Relative quantification of miR-124a and miR-34a expressions in serum was conducted by reverse transcriptase quantitative real-time polymerase chain reaction. Results: Expression levels of miR-124a and miR-34a in serum were significantly lower in RA patients (median: 0.64 and 0.30, respectively) compared to controls (median: 3.12 and 1.88, respectively), P < 0.001. Their serum levels were negatively associated with disease activity and inversely correlated with DAS28, C-reactive protein, and erythrocyte sedimentation rate (P < 0.001). Conclusion: Serum miR-124a and miR-34a could serve as potential noninvasive biomarkers for RA diagnosis and reflect the disease activity in RA patients.