MicroRNA-148b is down-regulated in non-small cell lung cancer and associated with poor survival

Background: The aim of this study was to clarify the clinicopathological significance of miRNA-148b (miR-148b) expression in NSCLC, and to explore the correlation between miR-148b level and the prognosis of patients with NSCLC. Methods: 151 patients diagnosed with NSCLC between May 2007 and April 2012 were included in the present study. Real-time RT-PCR method was used to assess the expression levels of miR-148b. The differences between two groups were assessed using Student’s t -test, and the Kaplan-Meier method was used to estimate overall survival. Results: The expression of miR-148b was decreased in tumor tissues compared to corresponding adjacent normal lung tissues (0.37 ± 0.12 vs. 1.00 ± 0.53, P < 0.05). Low miR-148b expression was significantly associated with TNM stage (P = 0.014), lymph node metastasis (P = 0.031), and distant metastasis (P = 0.008). Kaplan-Meier survival analysis showed that patients with low expression of miR-148b had significantly worse overall survival rates compared with those who had cancers with high miR-148b expression (log-rank test P = 0.039). Furthermore, multivariate Cox proportional hazards model analysis showed that miR-148b expression was independently associated with overall survival of patients with NSCLC (HR = 2.357, 95% CI: 1.612-9.212, P = 0.011). Conclusion: our data indicate that decreased expression of miR-148b in NSCLC tissues has prognostic value.