Abstract
Long non-coding RNA TGFB2-antisense RNA1 (TGFB2-AS1) has been reported could regulate tumorigenesis. However, the roles of TGFB2-AS1 in lung adenocarcinoma (LUAD) remain largely unknown. In this work, we aimed to explore the expression levels of TGFB2-AS1 and mechanisms in regulating LUAD progression. Expression level of TGFB2-AS1 in LUAD tissues and normal tissues was analyzed at StarBase. Moreover, its expression in LUAD cells and normal cell was analyzed with quantitative real-time polymerase chain reaction method. Gain- and loss-of-function studies were conducted to analyze the biological roles of TGFB2-AS1 in LUAD. Results indicated TGFB2-AS1 was evidently downregulated in LUAD tissues and cells. Moreover, as analyzed by cell counting kit-8 assay, wound-healing and transwell invasion assays, results revealed TGFB2-AS1 overexpression could suppress proliferation, migration and invasion abilities of LUAD cells in vitro and tumor growth in vivo. In addition, LncBase V2.0 and TargetScan prediction tools showed TGFB2-AS1 and endothelin receptor type B (EDNRB) shares binding site in microRNA-340-5p (miR-340-5p). Furthermore, luciferase activity reporter assay and RT-qPCR assay validated these prediction results. Furthermore, we showed TGFB2-AS1 functions as sponge for miR-340-5p to regulate EDNRB expression. Collectively, our results indicated TGFB2-AS1/miR-340-5p/EDNRB axis plays crucial roles in regulating LUAD progression, indicating TGFB2-AS1 may be a novel therapeutic target for LUAD.