Downregulated antisense lncRNA contributes to the development of lung adenocarcinoma.

The poor outcome of patients with lung adenocarcinoma (LUAD) highlights the importance to identify novel effective prognostic markers and therapeutic targets. Long noncoding RNAs (lncRNAs) have generally been considered to serve important roles in tumorigenesis and the development of various types of cancer, including LUAD. Here, we aimed to investigate the role of in LUAD and to explore its potential mechanisms by performing comprehensive bioinformatic analyses. The regulatory effect of on the expression of was validated by siRNA-based silencing. The effect of miR-421 on the modulation of was determined by miRNA mimics and inhibitors transfection. was expressed at lower levels in tumor parts and negatively correlated with unfavorable prognosis in LUAD patients. It exerted functions as a tumor suppressor gene by competitively binding to oncomir, miR-421, thereby attenuating expression. Transfection of lung cancer A549 cells with miR-421 mimics decreased the expression of . Transfection of lung cancer A549 cells with miR-421 inhibitors increased the expression of with lower cellular functions as proliferation and migration via epithelial-mesenchymal transition. In addition, inhibition of by siRNA transfection decreased the levels of , supporting the /miR-421/NR3C1 cascade. Moreover, the bioinformatic analysis also showed that could interact with the RNA-binding proteins (RBPs), CELF2 and QKI, consequently regulating RNA expression and processing. Taken together, we identified that and its indirect target can act as novel biomarkers for determining the prognosis of patients with LUAD, and further study is required.