MiR-300 Serves as Potential Biomarker to Screen Knee Osteoarthritis Patients by Targeting TNFα

This study mainly explored the serum level of miR-300 with the risk of knee OA, thereby evaluating their diagnostic ability for treatment of knee osteoarthritis (KOA) patients.In the current study, we evaluated the level of TNFα in KOA patients and HCs. The serum was used to quantify the level of TNF-α by way of a sandwich enzyme-linked immunosorbent assay. Dual luciferase reporter assay was carried out to identify the possible target gene of miR-300.In line with previous studies, our data showed that serum TNFα level was increased along with K/L grades and WOMAC scoring, suggesting TNFα induced inflammatory responses correlating with the severity of KOA. We also showed that serum miR-300 level was increased with the severity of KOA according to X ray examination and K/L grades. Furthermore, we showed that serum miR-300 level positively correlated with K/L grades, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain scoring and WOMAC function scoring. Bioinformatic predictions showed a conserved binding site of miR-300 in the 3'UTR of IκBα. We then carried out a dual luciferase reporter assay and found miR-300 significantly suppressed pmirGLO-IκBα-3'UTR luciferase activity.Serum miR-300 is increased with the severity of KOA according to X-ray examination and K/L grades, thereby reflecting the severity of KOA and the degree of cartilage damage. Therefore, it could be used as a potential biomarker to screen KOA patients from healthy controls.