Upregulation of microRNA-450 inhibits the progression of lung cancer in vitro and in vivo by targeting interferon regulatory factor 2.

MicroRNAs (miRNAs) are a class of non‑coding RNAs that play pivotal roles in human lung cancer development. The majority of studies have focused on either non-small cell lung cancer (NSCLC) or small cell lung cancer (SCLC). In the present study, we investigated a plausible mechanism of action of miR‑450 in these types of lung cancer. We found that the level of miR‑450 was decreased in lung cancer cell lines, as well as in solid tumors. As exemplified in the H510A (SCLC) and H2291 (NSCLC) cells, transfection with lentivirus carrying miR‑450 upregulated miR‑450 expression and significantly attenuated lung cancer cell proliferation and invasion, as well as the growth of implantated tumors. Interferon regulatory factor 2 (IRF2) was also verified to be a direct target of miR‑450 in lung cancer cells. The overexpression of IRF2 in the H510A and H2291 cells abrogated the inhibitory effects of miR‑450 on lung cancer cell proliferation and invasion. Taken together, in this study, we identified a novel role of miR‑450 in lung cancer. miR-450 targets IRF2 and thus supresses lung cancer cell proliferation and invasion.