Department of Nuclear Medicine, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, China.
Department of Minimally Invasive Intervention, Shaanxi Province Tumor Hospital, Xi'an, 710061, China.
J Bioenerg Biomembr. 2021 Jun;53(3):321-332. doi: 10.1007/s10863-021-09892-6. Epub 2021 Mar 19.
Lung cancer is one of the most common malignant tumors in the world. Non-small cell lung cancer (NSCLC) accounts for about 80% of all lung cancers. About 75% of patients are in the middle and advanced stages at the time of discovery, and the 5-year survival rate is very low. The aim of this study was to investigate the role of long non-coding RNA (lncRNA) NORAD in the pathogenesis of NSCLC. We found that lncRNA NORAD was highly expressed in human NSCLC tissues and cell lines. The CCK-8 assay results showed that lncRNA NORAD had no effect on cell proliferation. The Transwell assay and Western blotting results showed that overexpression of lncRNA NORAD promoted the invasion and epithelial-mesenchymal transition (EMT) of NSCLC cells. Then bioinformatics analysis was used to screen for candidate miRNA bound with lncRNA NORAD and the target gene of miRNA in NSCLC. The luciferase reporter gene assay and RNA pull-down assay were used to verify the relationship. We found that miR-363-3p expression was down-regulated, whereas PEAK1 expression was upregulated in NSCLC cells. We performed gain and loss function test of lncRNA NORAD, miR-363-3p and PEAK1, the results showed that while miR-363-3p-mimic inhibited cell invasion and EMT by targeting PEAK1, lncRNA NORAD acted as a sponge of miR-363-3p and promoted cell invasion and EMT by increasing the expression of PEAK1. In addition, p-ERK expression was detected by Western blotting to observe the effects of lncRNA NORAD, miR-363-3p and PEAK1 on activation of the ERK signaling pathway. Taken together, lncRNA NORAD upregulated the expression of PEAK1 through sponging miR-363-3p, and then activated the ERK signaling pathway, thereby promoting the development of NSCLC.
肺癌是世界上最常见的恶性肿瘤之一。非小细胞肺癌（NSCLC）约占所有肺癌的 80%。大约 75%的患者在发现时处于中晚期，5 年生存率非常低。本研究旨在探讨长链非编码 RNA（lncRNA）NORAD 在 NSCLC 发病机制中的作用。我们发现 lncRNA NORAD 在人 NSCLC 组织和细胞系中高表达。CCK-8 检测结果表明 lncRNA NORAD 对细胞增殖没有影响。Transwell 检测和 Western blot 结果表明，lncRNA NORAD 的过表达促进了 NSCLC 细胞的侵袭和上皮-间充质转化（EMT）。然后，利用生物信息学分析筛选与 lncRNA NORAD 结合的候选 miRNA 及其在 NSCLC 中的靶基因。通过荧光素酶报告基因检测和 RNA 下拉实验验证了它们之间的关系。我们发现，miR-363-3p 的表达在 NSCLC 细胞中下调，而 PEAK1 的表达上调。我们进行了 lncRNA NORAD、miR-363-3p 和 PEAK1 的增益和缺失功能测试，结果表明，miR-363-3p 模拟物通过靶向 PEAK1 抑制细胞侵袭和 EMT，而 lncRNA NORAD 作为 miR-363-3p 的海绵体，通过增加 PEAK1 的表达促进细胞侵袭和 EMT。此外，通过 Western blot 检测 p-ERK 表达，观察 lncRNA NORAD、miR-363-3p 和 PEAK1 对 ERK 信号通路激活的影响。综上所述，lncRNA NORAD 通过海绵吸附 miR-363-3p 上调 PEAK1 的表达，进而激活 ERK 信号通路，从而促进 NSCLC 的发展。
