Down-regulated MicroRNA 148b expression as predictive biomarker and its prognostic significance associated with clinicopathological features in non-small-cell lung cancer patients

BACKGROUND: Lung cancer is most common and is the leading cause of cancer-related death in both men and women worldwide. Understanding of the molecular mechanisms underlying non-small cell lung cancer (NSCLC) development and progression are important. In the present study, we investigated the potential role of miR-148b expression analysis as potential lung cancer biomarker with the correlation of circulating miR-148b to clinicopathological features. METHODS: A total of 104 NSCLC patients were diagnosed and cancer tissues together with adjacent normal tissues were evaluated. Quantitative Real-time PCR method was utilized to evaluate the expression levels of miR-148b. In addition, we investigated to clarify the relationship of miR-148b with clinicopathological features and survival in patients with NSCLC. RESULTS: Our findings showed that miR-148b was downregulated in tumor tissues when compared with corresponding adjacent normal lung tissues (0.34 ± 0.13 vs. 1.00 ± 0.57, P < 0.05). Moreover decreased expression of miR-148b was significantly related to TNM stage (P = 0.001) and lymph node-metastasis (P = 0.023). This findings suggested that miR-148b was down-regulated in NSCLC patients and may play a key role as a tumor suppressor gene in NSCLC. Kaplan-Meier survival analysis and log-rank test suggested that low-expression group of patients had significantly shorter overall survival than high-expression group (log-rank test: P = 0.031). Multivariate Cox proportional hazards model analysis indicated that low miR-148b expression was independently linked to poor survival of patients with NSCLC (HR = 3.215, 95 % CI: 1.543-10.621, P = 0.021) and other factors were not significant independent predictor of survival in patients with NSCLC. CONCLUSION: Our findings demonstrated that miR-148b may play a role as independent prognostic factor for patients with NSCLC.