Department of Cardiology, Tianjin Baodi Hospital, Baodi Clinical College of Tianjin Medical University, Tianjin 301800, P.R. China.
Department of Clinical Laboratory, Tianjin Baodi Hospital, Baodi Clinical College of Tianjin Medical University, Tianjin 301800, P.R. China.
Oncol Rep. 2020 Jul;44(1):115-125. doi: 10.3892/or.2020.7605. Epub 2020 May 7.
Long non‑coding RNAs (lncRNAs) have been validated to mediate the development of atherosclerosis (AS). In the present study, the molecular mechanisms and functions of lncRNA nuclear paraspeckle assembly transcript 1 (NEAT1) in the advancement of human aortic endothelial cells (HAECs) were investigated. The levels of lncRNA‑NEAT1 and miR‑638 expression in clinical samples and cells were explored via quantitative reverse transcription polymerase chain reaction. Colony formation and CCK‑8 assays were performed to determine the proliferative capacity of cells, and the apoptotic capacity of cells was analyzed on the basis of apoptotic cell proportion and caspase‑3 activity. Then, the proportion of cells and correlations among phosphoglycerate kinase 1 (PGK1), NEAT1, and miR‑638 were determined through RNA immunoprecipitation and luciferase assays and bioinformatics analysis. Moreover, the expression levels of Ki‑67, proliferating cell nuclear antigen, PGK1, Bax, Bcl‑2, (p)‑mTOR, (p)‑AKT, and β‑catenin were analyzed via western blot analysis. In the serum of patients with AS and HAECs induced by oxidized low‑density lipoprotein (ox‑LDL), the expression level of miR‑638 was decreased, whereas that of NEAT1 was increased. After ox‑LDL therapy, NEAT1 knockdown suppressed HAEC proliferation and stimulated HAEC apoptosis, which could be reversed by the miR‑638 inhibitor. NEAT1 inhibited miR‑638 expression through direct mutual action. The following mechanical investigations revealed that PGK1 was a miR‑638 target, whose expression was increased by NEAT1, a competing endogenous RNA of miR‑638. Additionally, the miR‑638 inhibitor contributed to proliferation and suppressed apoptosis through the activation of the AKT/mTOR signaling pathway in ox‑LDL‑induced HAECs. NEAT1 adjusted the AKT/mTOR signaling pathway via miR‑638 in ox‑LDL‑induced HAECs to accelerate their proliferation and impede their apoptosis. This result revealed that NEAT1 may be valuable in the treatment of AS.
长链非编码 RNA（lncRNA）已被证实可介导动脉粥样硬化（AS）的发生。本研究旨在探讨核小体旁聚核糖核酸 1（lncRNA-NEAT1）在人主动脉内皮细胞（HAEC）进展中的分子机制和功能。通过实时定量逆转录聚合酶链反应（qRT-PCR）检测临床标本和细胞中 lncRNA-NEAT1 和 miR-638 的表达水平。通过集落形成和 CCK-8 测定来检测细胞的增殖能力，并基于细胞凋亡比例和 caspase-3 活性来分析细胞的凋亡能力。然后，通过 RNA 免疫沉淀和荧光素酶测定以及生物信息学分析来确定 PGK1、NEAT1 和 miR-638 之间的细胞比例和相关性。此外，通过 Western blot 分析来检测 Ki-67、增殖细胞核抗原、PGK1、Bax、Bcl-2、（p）-mTOR、（p）-AKT 和β-连环蛋白的表达水平。在 AS 患者的血清和经氧化低密度脂蛋白（ox-LDL）诱导的 HAEC 中，miR-638 的表达水平降低，而 NEAT1 的表达水平升高。ox-LDL 治疗后，NEAT1 敲低抑制 HAEC 增殖并刺激 HAEC 凋亡，miR-638 抑制剂可逆转这一现象。NEAT1 通过直接相互作用抑制 miR-638 的表达。进一步的机制研究表明，PGK1 是 miR-638 的靶基因，其表达可被作为 miR-638 竞争性内源性 RNA 的 NEAT1 上调。此外，miR-638 抑制剂可通过激活 ox-LDL 诱导的 HAEC 中的 AKT/mTOR 信号通路促进增殖并抑制凋亡。NEAT1 通过 ox-LDL 诱导的 HAEC 中的 miR-638 调节 AKT/mTOR 信号通路，从而加速其增殖并抑制其凋亡。这些结果表明，NEAT1 可能在 AS 的治疗中具有重要价值。
