Combination of circulating miR-19b-3p, miR-122-5p and miR-486-5p expressions correlates with risk and disease severity of knee osteoarthritis.

The aim of this study was to investigate the association of circulating miRNAs profile with the risk of knee osteoarthritis (OA), and evaluate their correlation with clinical characteristics. This study was divided into two parts: exploration stage and validation stage. In exploration stage, 8 knee OA patients and 8 age and gender highly matched health controls (HCs) were recruited, and plasma sample were collected for microarray examination. Differentially expressed miRNAs and enrichment analysis were subsequently performed. In validation stage, 100 knee OA patients and 100 age and gender matched HCs were enrolled, and Top 8 differentially expressed miRNAs in microarray were selected for further validation by qPCR. In exploration stage, 41 up-regulated miRNAs and 29 down-regulated miRNAs were identified by microarray, and enrichment analysis disclosed these miRNAs were involved in inflammation- and immunity- related process. Top 8 differentially expressed miRNAs in microarray were determined in the validation stage, and miR-19b-3p, miR-92a-3p, miR-122-5p, miR-486-5p and miR-320b expression were increased in knee OA. Univariate and multivariate logistic analysis showed only miR-19b-3p, miR-122-5p and miR-486-5p were independent factors for knee OA risk, and ROC curve showed combination of miR-19b-3p, miR-122-5p and miR-486-5p has a great diagnostic value for knee OA. Besides, miR-19b-3p and miR-486-5p positively correlates with disease severity. This study revealed that circulating miRNA profiles played a key role in knee OA diagnosis, and combined measurement of miR-19b-3p, miR-122-5p and miR-486-5p could be served as a novel and promising biomarker for diagnosis and disease severity of knee OA.