Diagnostic and prognostic potentials of microRNA-27a in osteosarcoma

Growing evidence suggest that the microRNA (miR)-23a/24-2/27a cluster may play a crucial role in mammary tumorigenesis and act as a novel class of oncogenes. Among these members, miR-27a has been reported to promote proliferation, migration and invasion in human osteosarcoma cells. The aim of this study was to detect the serum levels of miR-27a in osteosarcoma patients and to investigate its associations with clinicopathological features and prognosis.

miR-27a levels in sera from 166 osteosarcoma patients and 60 healthy controls were detected by real-time quantitative RT-PCR. Then, the associations of serum miR-27a level with clinicopathological factors or survival of osteosarcoma patients were further evaluated.

Compared to healthy controls, the serum levels of miR-27a were significantly increased in osteosarcoma patients (P<0.001). Importantly, miR-27a could efficiently screen osteosarcoma patients from healthy controls (Area under receiver operating characteristic curve, AUC=0.867). Then, high miR-27a expression was more frequently occurred in osteosarcoma patients with advanced clinical stage (P=0.001), positive distant metastasis (P=0.01) and poor response to chemotherapy (P=0.008). In Kaplan-Meier survival analysis, high miR-27a expression was a significant indicator for poor overall survival (P=0.006) as well as poor disease-free survival (P=0.01). Furthermore, multivariate analysis demonstrated that miR-27a expression was an independent and significant prognostic factor to predict overall survival (P=0.01) and disease-free survival (P=0.03).

miR-27a expression may be elevated in sera of osteosarcoma patients and in turn contributes to aggressive progression of this malignancy. Detection of serum miR-27a levels may have clinical potentials as a non-invasive diagnostic/prognostic biomarker for osteosarcoma patients.