Background: Long non-coding RNA growth arrest specific 5 (GAS5) is a regulator in non-small cell lung cancer (NSCLC) progression. Nonetheless, the mechanism by which GAS5 exerts its biological function in NSCLC cells remains unclear.
Methods: GAS5, miR-221-3p relative expression levels in NSCLC tissues and cells were examined by qPCR. After gain-of-function and loss-of-function models were established, the viability of H1299 and A549 cells were examined by CCK-8 and EdU assays. Cell migration and invasion were examined by the Transwell experiment. The binding sequence of GAS5 for miR-221-3p was confirmed by the dual-luciferase reporter gene experiment. The regulatory function of GAS5 and miR-221-3p on IRF2 was investigated by Western blot.
Results: GAS5 expression was down-modulated in NSCLC tissues and cell lines. GAS5 overexpression restrained the proliferation, migration and invasion of NSCLC cells, while miR-221-3p, which was targeted and negatively modulated by GAS5, worked oppositely. Restoration of miR-221-3p markedly reversed the effects of GAS5 on NSCLC cells. Additionally, GAS5 increased IRF2 expression in NSCLC cells by repressing miR-221-3p.
Conclusions: GAS5 blocks the progression of NSCLC partly via increasing IRF2 expression level via repressing miR-221-3p.
Keywords: IRF2; NSCLC; lncRNA GAS5; miR-221-3p.