Upregulation of circular RNA hsa_circ_0007534 predicts unfavorable prognosis for NSCLC and exerts oncogenic properties in vitro and in vivo

Emerging evidence documented the key functions of circular RNAs (circRNAs) in various malignancies. Nevertheless, the research relevant to the clinical value and functions of circRNAs in non-small cell lung cancer (NSCLC) is still very limited. In this study, we performed qRT-PCR to assess the levels of hsa_circ_0007534 in NSCLC tissues and cell lines and evaluated its clinical significance using Fisher's exact test, Kaplan-Meier analysis and Cox regression analysis. Additionally, loss-of-function and gain-of-function experiments were performed to detect whether hsa_circ_0007534 could affect cell proliferation, apoptosis, metastatic properties and epithelial-mesenchymal transition (EMT) in A549 and H1299 cells. Further xenograft study was carried out to validate the in vitro data. The results indicated that hsa_circ_0007534 was up-regulated in both NSCLC tissue samples and cell lines and this up-regulation is linked to lymph node invasion and advanced TNM stage. Hsa_circ_0007534 could also function as an unfavorable prognostic indicator for the patients with NSCLC. For the part of functional assays, down-regulation of hsa_circ_0007534 suppressed cell growth, migratory and invasive capacities; facilitating cell apoptosis in A549 and H1299 cells. Conversely, up-regulation of hsa_circ_0007534 caused the opposite biological behaviors. What's more, animal experiments validated the oncogenic role of hsa_circ_0007534. Ultimately, the present study indicates that hsa_circ_0007534 might be a potential NSCLC-associated prognostic/therapeutic target.