Hsa-miR-1276 in peripheral blood mononuclear cells as a potential biomarker for rheumatoid arthritis

MicroRNAs (miRNAs) are increasingly recognized as pivotal regulators in autoimmune diseases. Rheumatoid arthritis (RA) is a chronic autoimmune disorder characterized by persistent inflammation, progressive joint destruction, and systemic complications. Although several miRNAs have been implicated in RA, their specific roles and clinical relevance remain unclear. This study aimed to identify and validate differentially expressed miRNAs in peripheral blood mononuclear cells (PBMCs) from patients with RA and evaluate their potential as diagnostic biomarkers. RNA sequencing (RNA-seq) was performed on PBMCs obtained from three RA patients and three healthy controls (HCs) to screen for differentially expressed miRNAs. Three candidate miRNAs were selected for validation and measured using real-time fluorescence quantitative PCR (RT-qPCR) in an independent cohort of 41 RA patients and 41 HCs. Receiver operating characteristic (ROC) curve analysis was used to evaluate the diagnostic performance. A total of 103 differentially expressed miRNAs were identified, with 34 upregulated and 69 downregulated in RA patients compared with HCs. RT-qPCR confirmed that hsa-miR-1276, hsa-miR-4433a-5p, and hsa-miR-409-3p were significantly upregulated in PBMCs of RA patients (P < 0.05), consistent with the sequencing results. Among them, hsa-miR-1276 showed promising diagnostic accuracy, with an area under the ROC curve (AUC) of 0.9726. Hsa-miR-1276 is significantly upregulated in PBMCs of RA patients and demonstrates promising diagnostic potential. These findings suggest that hsa-miR-1276 may serve as a novel biomarker for the diagnosis of RA.