Inhibitory Effect of MiR-449b on Cancer Cell Growth and Invasion through LGR4 in Non-Small-Cell Lung Carcinoma

摘要

Non-small-cell lung carcinoma (NSCLC) is one of the most frequently diagnosed malignancies worldwide.Previous studies have shown that microRNA-449b (miR-449b) functions as a tumor suppressor in many cancers.However,the role of miR-449b in NSCLC is still unknown.In the present study,miR-449b was significantly downregulated in NSCLC samples and cell lines.Bioinformatics analysis revealed that 3'-UTR region of leucine rich repeat containing G protein-coupled receptor 4 (LGR4) mRNA had putative complementary sequences to miR-449b,which was further confirmed by the luciferase assay.Western blotting showed that restoration of miR-449b in NSCLC cells decreased the expression of LGR4.Interestingly,over-expression of miR-449b inhibited growth and invasion of NSCLC cells in vitro.Furthermore,ectopic expression of LGR4 reversed miR-449b-suppressed proliferation and invasion of NSCLC cells.Therefore,the data of the present study demonstrate that miR-449b inhibits tumor cell growth and invasion by targeting LGR4 in NSCLC.