Serum miR-210 and miR-155 expression levels as novel biomarkers for rheumatoid arthritis diagnosis

Background: MicroRNAs play a crucial role in the regulation of immune response. We hypothesised roles for serum miR-210 and miR-155 in the diagnosis of rheumatoid arthritis (RA) and relationships with the clinical and laboratory variables including erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), rheumatoid factor (RF), anti-cyclic citrullinated peptide (CCP) antibodies, tumour necrosis factor-alpha (TNF-α) and interleukin-1β (IL-1β). Methods: MiR-210 and miR-155 levels were identified by real-time polymerase chain reaction (PCR). TNF-α and IL-1β were measured by enzyme-linked immunosorbent assay and routine markers by standard techniques in 100 patients with RA and 100 individuals as healthy controls. Disease activity in the patients was assessed by DA-S28. Results: MiR-210 was lower in RA compared to controls [median/IQR 0.96 (0.8-1.24) vs. 4 (1.28-3.93), p