Serum Expression of Mir-488-3p Serves as a Non-Invasive Diagnostic Biomarker in Patients with Rheumatoid Arthritis.

The diagnosis of rheumatoid arthritis (RA) remains challenging because of the limitations of existing biomarkers. The purpose of the study was to investigate the potential of miR-488-3p in serum as a biomarker for RA and to reveal its potential mechanism of action. The study included 135 RA patients, 130 osteoarthritis (OA) patients, and 125 healthy controls. miR-488-3p expression levels were examined by RT-qPCR. The mechanism of action was analyzed by functional tests (CCK-8, flow cytometry, ELISA) and target validation experiments (luciferase reporter gene, RIP). Serum miR-488-3p expression levels were significantly lower in RA patients than in osteoarthritis (OA) patients and healthy controls (p < 0.001). ROC curve analysis showed that miR-488-3p had a high diagnostic accuracy in distinguishing RA from healthy controls and OA patients. miR-488-3p negatively correlated with erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP), rheumatoid factor (RF), and DAS28 scores. Functional validation revealed that overexpression of miR-488-3p inhibited the proliferation and inflammatory response of synoviocytes while inducing apoptosis. Mechanistic studies showed that miR-488-3p could directly target Rho-associated coiled-coil containing protein kinase 1 (ROCK1), which mediates its protective effects. Serum miR-488-3p holds promise as a novel non-invasive diagnostic marker for RA and protects synoviocyte from injury.