MicroRNA-10b indicates a poor prognosis of non-small cell lung cancer and targets E-cadherin

MicroRNA-10b(miR-10b) has been reported to be dysregulated in some types of cancer and to play an important role in invasion and metastasis. It was previously found to be a tumor enhancer in NSCLC; however, its clinical significance in NSCLC has not been evaluated. We compared the expression levels of miR-10b in 73 pairs of NSCLC tissues and the corresponding noncancerous tissues, as well as in human lung cancer cell line A549 and NHBE cell line by qRT-PCR. Expression of E-cadherin (E-cad) was detected using RT-PCR and Western blot analysis. The disease-specific survival (DSS) was analyzed by log-rank test, and survival curves were plotted according to Kaplan-Meier. MiR-10b was significantly upregulated in NSCLC tissues as well as in A549 cell line. The relative miR-10b expression levels were significantly positively correlated with TNM stage (p = 0.01) and regional lymph node involvement (p < 0.001). Kaplan-Meier analysis showed that patients with higher levels of miR-10b had significantly poorer survival than those with lower expression of this miRNA in patients, with a 5-year DSS of 29.5 and 63.8 %, respectively (p = 0.003). The E-cad mRNA and protein were overexpressed in miR-10b-suppressed cells compared with controls. Our results indicated that miR-10b expression was an independent prognostic factor in NSCLC patients. Furthermore, miR-10b might be necessary for driving the expression of E-cad in NSCLC.