Expression and clinical significance of microRNA-148a in patients with non-small cell lung cancer

Abstract

Objective To investigate the expressions of microRNA-148a (miR-148a) in non-small cell lung cancer (NSCLC) tissues and adjacent non-tumor tissues and the relationships with clinicopathologic features, to analyze the roles of miR-148a in evaluating prognosis. Methods Expression levels of miR-148a in 48 pairs of NSCLC and adjacent non-tumor tissues were detected by quantitative real-time PCR (RT-PCR). The patients were divided into 2 groups according to the median value of miR-148a. The relationships between the expression levels of miR-148a and clinicopathological features were analyzed. The survival rate was estimated by Kaplan-Meier method, and single factor analysis was performed. The relationship between the expression level of miR-148a and prognosis was analyzed by Log-rank test. Results miR-148a expression levels were significant down-regulated in NSCLC tissues compared with adjacent non-tumor tissues (1.052 ± 0.659 vs. 1.397 ± 0.667, t=2.549, P=0.013). miR-148a expression level was correlated with tumor size (χ2=4.594, P=0.030), lymph nodes metastasis (χ2=5.486, P=0.019) and clinical stage (χ2=4.090, P=0.043), while it was not correlated with age (χ2=0.354, P=0.551), gender (χ2=2.277, P=0.131), histological type (χ2=0.403, P=0.525) and smoking (χ2=0.444, P=0.505). Kaplan-Meier analysis revealed a significant correlation between low miR-148a expression level and poor overall survival (23.9 months vs. 38.7 months, χ2=4.941, P=0.026), and no significant correlation with progression-free survival (21.6 months vs. 29.4 months, χ2=2.168, P=0.141). Conclusion Down-regulation of miR-148a is correlated with worse clinicopathological features, which serves an independent marker for poor prognosis in patients with NSCLC. Key words: Carcinoma, non-small-cell lung; MicroRNAs; Pathological conditions, signs and symptoms; Survival analysis