Abstract：
Circular RNAs (circRNAs) play critical roles in the recurrence and progression of non-small-cell lung cancer (NSCLC). This study aimed to investigate the function and underlying mechanism of a novel circRNA (circRPPH1) in NSCLC. Localization of circRPPH1 was determined via FISH assay, while cell proliferation was assessed via CCK8 and colony formation assay. Cell migration and invasion were studied using transwell assay, while binding sites between miR-326 and circRPPH1 or ERBB4 were verified by luciferase reporter, RIP, and RNA pull-down assays. Moreover, xenograft assay was performed to verify the in vivo roles of circRPPH1. Results indicated that circRPPH1 was highly expressed in NSCLC tissues and cells, where circRPPH1 levels were predictive of poor prognosis. The malignant behavior of NSCLC cells was exacerbated by overexpressing circRPPH1, while opposite effects were observed when it was knocked down. Direct interaction between miR-326 and circRPPH1 or ERBB4 was confirmed in NSCLC cells, while rescue experiment results showed that circRPPH1 exerted an oncogenic role via miR-326-ERBB4 signal axis. Moreover, in vitro, growth of NSCLC cells was significantly attenuated following circRPPH1 depletion. The study concluded that circRPPH1 was involved in promoting NSCLC progression via the miR-326/ERBB4 axis, which provided a novel potential target for the diagnosis or treatment of NSCLC.
摘要：
环状RNA（circularRNAs，circRNAs）在非小细胞肺癌（NSCLC）的复发和进展中起关键作用。本研究旨在探讨一种新型circRNA(circRPPH1)在非小细胞肺癌中的功能和潜在机制。通过FISH测定确定circRPPH1的定位，同时通过CCK8和集落形成试验评估细胞增殖。使用transwell测定法研究细胞迁移和侵袭，虽然miR-326和circRPPH1或ERBB4之间的结合位点通过荧光素酶报告基因验证，RIP,和RNA下拉法。此外，进行异种移植试验以验证circRPPH1的体内作用。结果表明circRPPH1在NSCLC组织和细胞中高表达，其中circRPPH1水平可预测不良预后。过度表达circRPPH1会加剧NSCLC细胞的恶性行为，而当将其击倒时，观察到相反的作用。在NSCLC细胞中证实了miR-326与circRPPH1或ERBB4之间的直接相互作用，而拯救实验结果表明circRPPH1通过miR-326-ERBB4信号轴发挥致癌作用。此外，在体外，circRPPH1耗竭后，NSCLC细胞的生长显著减弱。该研究得出结论，circRPPH1通过miR-326/ERBB4轴参与促进NSCLC进展，这为NSCLC的诊断或治疗提供了新的潜在靶点。
