Expression of nucleostemin gene in primary osteoarthritis

The identification of genes associated with osteoarthritis can help reveal underlying biological mechanisms that may lead to development of new therapeutic targets or biomarkers for early detection and risk stratification. Nucleostemin (GNL3) is a nucleolar GTPase initially identified in the nucleolus of rat neural stem cells. The current study was conducted to determine the expression of nucleostemin gene in the synovium and synovial fluid of patients with primary osteoarthritis and to correlate its expression to the different clinicopathological factors of the disease.

It included 31 patients with primary knee osteoarthritis and 25 osteoarthritis free patients served as a control group. Synovial tissue and synovial fluid samples were obtained directly from each patient for real time PCR of GNL3.

Relative expression of GNL3 in synovial tissue and fluid samples was significantly higher in the osteoarthritic group as compared to the non-osteoarthritic group. GNL3 relative expression in both samples showed a significant difference among different BMI categories and among different radiographic grades of osteoarthritis. A high significant correlation was found between GNL3 relative expression levels in synovial tissue samples and those of synovial fluid samples with concordance of 85.7%.

Nucleostemin could serve as a powerful prognostic marker for clinical use in osteoarthritis and its usefulness needs to be standardized and validated in a large-scale prospective multicentric study.