MicroRNA-26a reduces synovial inflammation and cartilage injury in osteoarthritis of knee joints through impairing the NF-κB signaling pathway.

Objective: Inflammation is closely implicated in the process of osteoarthritis (OA) and affects disease progression and pain. Herein, the present study explored the effect of microRNA-26a (miR-26a) on the synovial inflammation and cartilage injury in OA, with the involvement with the NF-κB signaling pathway.Methods: Rat models of OA were established by anterior cruciate ligament transection, which were then treated with miR-26a mimics/inhibitors or BMS-345541 (inhibitor of NF-κB pathway). The expression of miR-26a and activator proteins of NF-κB pathway (P-IκBα and P-P65) in synovial tissues was determined. Hematoxylin-eosin (HE) staining was adopted to observe pathological changes of knee joints, synovial tissues, and cartilage of femoral condyle. Terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) staining was used to detect the apoptosis of synoviocytes and chondrocytes.Results: Poorly expressed miR-26a and increased protein levels of P-IκBα and P-P65 were identified in synovial tissues of OA rats. Besides, OA rats showed obvious synovial tissue hyperplasia, inflammation and cartilage injury of femoral condyle, as well as increased inflammation and cartilage injury scores, and apoptosis of synoviocytes and chondrocytes. In response to miR-26a mimics, protein levels of P-IκBα and P-P65 were reduced; meanwhile, synovial tissue hyperplasia, inflammation and cartilage injury of femoral condyle were ameliorated, with decreased inflammation and cartilage injury scores, and apoptosis of synoviocytes and chondrocytes.Conclusion: MiR-26a suppressed the activation of the NF-κB signaling pathway, by which mechanism the synovial inflammation and cartilage injury in OA rats were alleviated.

Ollier disease: two case reports and a review of the literature.

Ollier disease is a rare tumor with unclear clinicopathological features and pathogenesis. We herein report two cases of Ollier disease in a 15-year-old boy and a 66-year-old man. We analyzed the clinicopathological, radiographical, and histochemical characteristics of Ollier disease in these two cases. Furthermore, we reviewed the literature to better understand the clinicopathological features of this disease. The boy had multiple enchondromas in the metaphysis and upper region of the left femur, and his left leg is short naturally. The 66-year-old man had multiple enchondromas in his left ribs and lower segment of the left femur. He was sent to the hospital because of pathological fracture of the ribs. In addition, he was diagnosed with gastric cancer 4 years before visiting an orthopedic clinic. Ollier disease is a rare bone disease that often renders a typical asymmetrical distribution and is confined to the appendicular skeleton. It is known as a benign bone tumor and has a high risk of malignant transformation into a chondrosarcoma (5%-50%). Correct diagnosis requires radiographic, histochemical, and morphological analyses. Better understanding of the clinical manifestations and pathological features can improve the diagnosis and prevent malignant transformation and deformity, especially in adolescent patient.