Expression of MiR-140 and MiR-199 in Synovia and its Correlation with the Progression of Knee Osteoarthritis

BACKGROUND The aim of this study was to explore the expression of miR-140 and miR-199 in synovia of patients with knee osteoarthritis (KOA) and its correlation with the progression of this disease. We used the Kellgren and Lawrence grading (KLG) system. MATERIAL AND METHODS There were 110 patients with early (KLG <2), middle (KLG=2) and late (KLG >2) stage KOA and 60 healthy individuals (control) included in this study. RESULTS The relative expression levels of miR-140 (1.07±0.091) and miR-199 (1.03±0.110) in synovia of the control group were higher than those of KOA groups (0.511±0.130, 0.298±0.168) and the difference exhibited statistical significance (P<0.01). Expression of miR-140 in the middle and the late stage KOA groups (0.322±0.118 and 0.110±0.088 respectively) were 58.80% and 81.29% lower, respectively, compared to the early stage KOA group (0.588±0.172), which was significant (P<0.05). Expression of miR-199 in the middle and the late stage KOA groups (0.210±0.124 and 0.056±0.068 respectively) were 39.41% (P<0.05) and 83.72% (P<0.01) respectively lower than that in the early KOA group (0.344±0.147). The severity of OA was significantly negatively correlated with the expressions of miR-140 and miR-199 (r=-0.859, P<0.05; r=-0.724, P<0.001 respectively). Matrix metalloproteinase (MMP)-3 levels of the early stage, middle stage and late stage KOA groups were 1.320±0.118, 1.488±0.210, and 1.955±0.023 respectively; and IL-1ß mRNA was 1.401±0.204, 1.522±0.210, and 1.889±0.217 respectively, which were obviously higher than those in the control group (1.020±0.085), (P<0.05). CONCLUSIONS Expression levels of miR-140 and miR-199 in synovia might act as an early diagnostic marker for KOA. These expression levels might also act as indicators of OA progression to some extent.