LncRNA SNHG20 promoted proliferation, invasion and inhibited cell apoptosis of lung adenocarcinoma via sponging miR‐342 and upregulating DDX49

BACKGROUND: There is increasing evidence that long non‐coding RNA (lncRNA) small nucleolar RNA host gene 20 (SNHG20) plays an important role in cancer. However, the function of SNHG20 in lung adenocarcinoma is unclear. The aim of our study was to investigate the roles of SNHG20 in lung adenocarcinoma. METHODS: Real‐time quantitative polymerasechain reaction (RT‐qPCR) was used to calculate the expression of SNHG20, miR‐342 and DEAD‐box helicase 49 (DDX49). Dual luciferase reporter gene assay was applied to verify whether miR‐342 binding to SNHG20 and DDX49. The expression correlation between miR‐342 and SNHG20 or DDX49 was assessed using Pearson's correlation analysis. RESULTS: SNHG20 and DDX49 were overexpressed, while miR‐342 was lowly expressed in lung adenocarcinoma tissues and cell lines. Knockdown of SNHG20 suppressed cell proliferation, invasion and enhanced cell apoptosis. SNHG20 was found to directly bind to miR‐342 and regulate the expression of miR‐342. MiR‐342 directly targeted DDX49 and the expression of miR‐342 had negative connection with DDX49 in lung adenocarcinoma tissues. Knockdown of DDX49 inhibited the progression of lung adenocarcinoma. DDX49 partially restored the functions of SNHG20 in A549 cells. CONCLUSIONS: SNHG20 regulated lung adenocarcinoma cell proliferation, invasion and promoted cell apoptosis via miR‐342/DDX49 axis. Our findings demonstrate that SNHG20/miR‐342/DDX49 axis plays an important role in lung adenocarcinoma, providing a novel insight into the treatment of lung adenocarcinoma.