Long non-coding RNA MEG3 regulates proliferation and apoptosis in non-small cell lung cancer via the miR-205-5p/LRP1 pathway

Long non-coding RNA (lncRNA) MEG3 has been identified as a tumor suppressor in various cancers including non-small cell lung cancer (NSCLC). However, its molecular mechanisms in the development and progression of NSCLC have not been thoroughly elucidated until now. Here, we identified that the expression levels of MEG3 and miR-205-5p were respectively down-regulated and up-regulated in human NSCLC tissues and cells. Bioinformatics analysis, luciferase reporter assays, and RNA immunoprecipitation (RIP) assays combined with western blot assays further validated that MEG3 inhibited miR-205-5p expression via direct interaction. Function and mechanism analysis revealed that the exogenous expression of MEG3 hindered proliferation and induced apoptosis by acting as a miR-205-5p sponge to enhance low-density lipoprotein (LDL) receptor-related protein-1 (LRP1) expression in NSCLC. Moreover, a transplantation experiment demonstrated that MEG3 exerted an oncosuppressive effect via the miR-205-5p/LRP1 axis. Taken together, our study demonstrates that MEG3 represses tumorigenesis through regulating the miR-205-5p/LRP1 pathway in NSCLC.