Background: Rheumatoid arthritis (RA) leads to joint deformities or permanent disability. The erratic expression of various micro-RNAs (miRNAs) is strongly associated with RA. This research assessed the significance of miRNA-146a and miRNA-155 as predictors of RA development. We also assessed their promising application as biomarkers of RA disease activity.
Methods: This case-control study included 62 subjects (31 RA patients and 31 healthy controls). Participants' sera were used for laboratory tests and measuring miRNA-146a and miRNA-155 gene expression.
Results: In RA patients, miRNA-146a and miRNA-155 expressions were significantly higher than in controls (P<0.001). The receiver operating characteristic (ROC) curve analysis showed that miRNA-146a could predict RA with area under curve (AUC) 0.857, sensitivity 77.4%, and specificity 80.6% (P<0.001) at 95% confidence interval (CI). MiRNA-155 could predict RA with AUC 0.829, sensitivity 77.4% and specificity 67.7% (P<0.001) at 95% CI. Active RA patients expressed more miRNA-146a and miRNA-155 than the inactive group. There was a significant positive correlation (P<0.05) among miRNAs-146a and155 expression levels and DAS-28 score in RA patients. MiRNA -146a increased the risk of active RA significantly independently by 2.023 folds. The ROC curve showed that miRNA -146a is useful for predicting RA disease activity with AUC 0.905, sensitivity 91.3% and specificity 87.5% (P<0.001) at 95% CI .
Conclusion: MiRNA-146a and miRNA-155 expressions were remarkable in RA patients and were recognized as potential biomarkers for early RA diagnosis. MiRNA- 146a expression is an independent risk for active RA and could be a valuable biomarker to predict RA disease activity.