SP1-upregulated LBX2-AS1 promotes the progression of glioma by targeting the miR-491-5p/LIF axis

Background: Mounting evidences have shown the importance of lncRNAs in carcinogenesis and cancer progression. LBX2-AS1 is identified as an oncogenic lncRNA that is abnormally expressed in gastric cancer and lung cancer samples. This study aims to explore the potential role of LBX2-AS1 in regulating proliferation and EMT in glioma, and the underlying mechanism. Methods: Relative levels of LBX2-AS1 in glioma samples and cell lines were detected by qRT-PCR and FISH. In vivo and in vitro regulatory effects of LBX2-AS1 on proliferation and EMT were examined in the xenograft glioma model and glioma cells. The interaction between SP1 and LBX2-AS1 was assessed by ChIP. Through bioinformatic analyses, dual-luciferase reporter assay, RIP and Western blot, the regulation of LBX2-AS1 and miR-491-5p on the target gene LIF was identified. Results: LBX2-AS1 was upregulated in glioma samples and cell lines, and its transcription was promoted by binding to the transcription factor SP1. As a lncRNA mainly distributed in the cytoplasm, LBX2-AS1 sponge miR-491-5p to further upregulate LIF. The subsequent activated LIF/STAT3 signaling was responsible for promoting proliferation and EMT in glioma. Conclusion: LBX2-AS1 is upregulated by SP1 in glioma, which promotes the progression of glioma by targeting the miR-491-5p/LIF axis. In view of this, LBX2-AS1 is suggested as a novel diagnostic biomarker and therapeutic target of glioma.