Circulating microRNA-137 is a potential biomarker for human glioblastoma.

OBJECTIVE In this study, we investigated whether circulating microRNA-137 (miR-137) could be a potential biomarker for patients with glioblastoma (GBM). PATIENTS AND METHODS Serum samples were collected from 64 GBM patients and 64 healthy controls. The expression level of circulating miR-137 was compared by quantitative RT-PCR. Among GBM patients, circulating miR-137 was compared between patients at early stages and those at advanced stages. Also, the correlations of serum miR-137 expression with clinicopathological features and overall survival of GBM patients were statistically examined. Furthermore, whether circulating miR-137 could serve as an independent predicting biomarker GBM patients' survival was assessed. RESULTS Serum miR-137 was downregulated in GBM patients than in healthy controls. It was further downregulated in GBM patients at advanced stages than in patients at early stages. Statistical analysis demonstrated that low serum miR-137 level was strongly correlated with patients' clinical grades (p = 0.003) and KFS (p = 0.002). Low serum miR-137 was also found to be significantly correlated with, and may predict poor survival in GBM patients. CONCLUSIONS Downregulated serum miR-137 may be a potential non-invasive prognostic biomarker for poor prognosis in GBM patients.