Down-regulation of microRNA-143 contributes to unfavorable prognosis for patients with nasopharyngeal carcinoma

Background: MicroRNAs (miRNAs) can serve as biomarker for prognosis in many cancers. However, little is known about the role of miR-143 for prognosis in nasopharyngeal carcinoma (NPC). Methods: Quantitative real time polymerase chain reaction (qRT-PCR) was used to quantify miR-143 expression in NPC tissues. The relationship of miR-143 expression with clinicopathological parameters of NPC patients was analyzed using Chi-square test. Kaplan-Meier curves were used to estimate the association between miR-143 expression and overall survival. A Cox proportional hazards modeling was performed to identify the prognostic value of miR-143 expression in NPC patients. Results: MiR-143 was significantly down-regulated in NPC clinical tissues (P < 0.05). There were significantly relationship between low miR-143 expression and clinicopathological features, such as clinical stages (P = 0.000), T classification (P = 0.002), N classification (P = 0.014), locoregional recurrence (P = 0.001), and distant metastasis (P = 0.032). In addition, patients with low expression of miR-143 had poorer overall survival than that with high expression (P = 0.000). Furthermore, miR-143 was an independent prognostic factor in NPC in multivariate Cox regression analysis (P = 0.001, HR: 2.847, 95% CI: 1.513-5.360). Conclusion: Our study presents that miR-143 may serve as an important tumor suppressor and indicates that down-regulated expression of miR-143 in NPC could be used as a potential prognostic marker.