MicroRNA-199b targets the regulation of ZEB1 expression to inhibit cell proliferation, migration and invasion in non‑small cell lung cancer.

Lung cancer is one of the leading causes of cancer-associated mortality worldwide. Previous evidence suggested that microRNAs (miRs) exhibit important regulatory roles in tumorigenesis and tumor development, including in non-small cell lung cancer (NSCLC). The present study investigated the expression of miR-199b in NSCLC tissues and cell lines, in addition to the biological roles of miR-199b in the carcinogenesis and progression of NSCLC. The results of the present study demonstrated that miR-199b expression was decreased in NSCLC tissues and cell lines compared with matched adjacent healthy tissues and a healthy human bronchial epithelial cell line, respectively. An MTT assay demonstrated that the viability of NSCLC cells was decreased by miR-199b. The migratory and invasive abilities of NSCLC cells were suppressed by miR-199b overexpression. In addition, zinc finger E-box-binding homeobox 1 (ZEB1) was identified to be a novel direct downstream and functional target for miR-199b in NSCLC, using bioinformatics analysis, luciferase reporter assay, the reverse transcription-quantitative polymerase chain reaction and western blotting. ZEB1 underexpression mimicked the roles of miR-199b overexpression in NSCLC cells. In conclusion, the present study demonstrated that miR-199b was downregulated in NSCLC and acted as a tumor suppressor by targeting ZEB1.