Inhibition of microRNA-939 suppresses the development of human non-small cell lung cancer via the upregulation of tissue inhibitor of metalloproteinases 2

Numerous microRNAs (miRNA/miRs) have been reported to be associated with the initiation and progression of non-small cell lung cancer (NSCLC). The aim of the present study was to examine the expression and biological role of miR-939 in human NSCLC, in vitro. Reverse transcription-quantitative polymerase chain reaction analysis was used to evaluate the expression of miR-939 in NSCLC tissues. Cell Counting Kit-8, 5-ethynyl-29-deoxyuridine and Transwell assays were also used to determine the effects of miR-939 on tumor cell proliferation and invasion in two human NSCLC cell lines (H1299 and SPCA1). Furthermore, tissue inhibitor of metalloproteinases 2 (TIMP2) was confirmed to be a target of miR-939 by luciferase reporter assay, western blotting and bioinformatics analysis. Following downregulation of miR-939 expression, cell proliferative and invasive abilities were significantly suppressed. Collectively, these findings indicated that the knockdown of miR-939 may inhibit cell proliferation and invasion by regulating the expression of TIMP2 in NSCLC cells. Thus, miR-939 may be a potential target in the treatment of NSCLC, although this requires further investigation.