Circ_0000514 promotes the malignant biological behaviors of non-small cell lung cancer cells by modulating miR-330-5p and HMGA2

Background: Circular RNA 0000514 (circ_0000514) has a modulatory function in the progression of several cancers, but its role and mechanism in non-small cell lung cancer (NSCLC) are obscure.& nbsp;Methods: The relative expressions of circ_0000514, microRNA-330-5p (miR-330-5p) and high mobility group AT-hook 2 (HMGA2) mRNA in 67 cases of NSCLC and adjacent lung tissues were examined by quantitative realtime polymerase chain reaction (qRT-PCR). The changes in cell phenotypes were examined by cell counting kit-8 (CCK-8), 5-Ethynyl-2 '-deoxyuridine (EdU), Transwell and flow cytometry assays, respectively. Bioinformatics analysis, dual-luciferase reporter gene experiment and RNA immunoprecipitation (RIP) experiment were adopted to predict and validate the relationship between circ_0000514 and miR-330-5p, and miR-330-5p and HMGA2 3 ' UTR, respectively. In addition, Western blot was performed to examine the effects of circ_0000514 overexpression or knockdown on HMGA2 protein expression.& nbsp;Results: Circ_0000514 expression was up-regulated in NSCLC tissues. Circ_0000514 significantly facilitated the growth, cell cycle progression, metastatic potential, and repressed the apoptosis of NSCLC cells. Circ_0000514 was identified as a molecular sponge to decoy miR-330-5p, and HMGA2 was proven to be a target gene of miR330-5p. Moreover, circ_0000514 positively regulated HMGA2 expression, and its biological effect was dependent on miR-330-5p/HMGA2 axis.& nbsp;Conclusion: Circ_0000514 is an oncogenic circRNA in NSCLC progression, and it modulates miR-330-5p/HMGA2 axis.