Up-regulation of serum miR-744 predicts poor prognosis in patients with nasopharyngeal carcinoma.

BACKGROUND MiRNAs has been shown to be implicated in the pathogenesis of many human diseases including cancer. Dysregulation of miR-744 is common in a number of cancers, indicating miR-774 might be closely correlated with the tumorigenesis process. However, the role and clinical significance of miR-774 in nasopharyngeal carcinoma (NPC) is poorly known. Thus the aim of this study is to investigate whether there was any clinical value of serum miR-744 in detecting and predicting the prognosis of NPC. MATERIALS AND METHODS Real-time PCR was used to examine the expression level of serum miR-744 in patients with NPC and the healthy volunteers. The changes in serum miR-744 expression level of NPC patients after receiving chemo-radiotherapy were also evaluated. The association between pre-treatment serum miR-744 expression level and NPC clinicopathological parameters was investigated. Finally we employed Kaplan-Meier method and Cox proportional hazards model to evaluate the clinical value of serum miR-744 in predicting the prognosis of NPC. RESULTS Our study showed the expression level of serum miR-744 was significant higher in patients with NPC in comparison with healthy controls (P<0.01). The serum miR-744 expression level was down-regulated significantly in NPC patients after receiving chemo-radiotherapy (P<0.01). The Pre-treatment Serum miR-744 expression level was correlated with various important NPC clinicopathological parameters including N stage, clinical stage and grade. In addition, NPC patients with higher serum miR-744 expression had poorer 5 year overall survival rate and relapse-free survival rate. What was more, serum miR-744 was showed to be an independent factor for predicting the prognosis of NPC. CONCLUSION Serum miR-744 was up-regulated in NPC patients. Higher expression level of serum miR-744 was closely correlated with was associated with poor prognosis in NPC and it might be employed as a potential biomarker for predicting the clinical outcome of NPC patients.