Expression of microRNA-218 in nasopharyngeal carcinoma and its clinical significance

Objective: To investigate the expression of miR-218 (microRNA-218) in NPC (nasopharyngeal carcinoma) tissues and its clinical significance. Methods: A series of 54 tissue biopsies obtained from NPC patients and 35 control tissues with no-NPC (normal nasopharyngeal mucosa or chronic inflammation of nasopharyngeal mucosa) were collected. RFQ-PCR (real-time fluorescence-based quantitative PCR) was used to detect the miR-218 expressions in these samples. The correlations of miR-218 expression with clinicopathological characteristics and prognosis of NPC patients were analyzed. Results: Compared with the control tissues, miR-218 was consistently down-regulated in NPC tissues. The average expression level of miR-218 in NPC tissues was significantly lower than that of the control tissues (P = 0.000). The expression level of miR-218 in poorly differentiated NPC was significantly reduced as compared with well/moderately differentiated NPC (P = 0.032). The expression level of miR-218 in clinical stages Ⅲ/Ⅳ NPC was lower than that in clinical stages Ⅰ/Ⅱ NPC (P = 0.007). Moreover, the expression level of miR-218 in NPC patients with lymph node metastasis was significantly lower than that in NPC patients without lymph node metastasis (P = 0.019). NPC patients with a higher level of miR-218 expression had also a longer survival (P < 0.05).  Conclusion: The expression of miR-218 is associated with carcinogenesis, progression and prognosis of nasopharyngeal carcinoma, so it may be used as a potential therapeutic target, a diagnostic biomarker and a prognostic predictor in patients with NPC in future. DOI:10.3781/j.issn.1000-7431.2013.02.012