Wang Yixuan, Sun Qian, Geng Rongxin, Liu Hao, Yuan Fan'en, Xu Yang, Qi Yangzhi, Jiang Hongxiang, Chen Qianxue, Liu Baohui
Department of Neurosurgery, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China.
Central Laboratory, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China.
Oncol Lett. 2021 Apr;21(4):303. doi: 10.3892/ol.2021.12564. Epub 2021 Feb 19.
Notch intracellular domain (NICD), also known as the activated form of Notch1 is closely associated with cell differentiation and tumor invasion. However, the role of NICD in glioblastoma (GBM) proliferation and the underlying regulatory mechanism remains unclear. The present study aimed to investigate the expression of NICD and Notch1 downstream gene HES5 in human GBM and normal brain samples and to further detect the effect of NICD on human GBM cell proliferation. For this purpose, western blotting and immunohistochemical staining were performed to analyze the expression of NICD in human GBM tissues, while western blotting and reverse-transcription quantitative PCR experiments were used to analyze the expression of Hes5 in human GBM tissues. A Flag-NICD vector was used to overexpress NICD in U87 cells and compound E and small interfering (si) Notch1 were used to downregulate NICD. Cellular proliferation curves were generated and BrdU assays performed to evaluate the proliferation of U87 cells. The results demonstrated that compared with normal brain tissues, the level of NICD protein in human GBM tissues was upregulated and the protein and mRNA levels of Hes5 were also upregulated in GBM tissues indicating that the Notch1 signaling pathway is activated in GBM. Overexpression of NICD promoted the proliferation of U87 cells while downregulation of NICD by treatment with compound E or siNotch1 suppressed the proliferation of U87 cells . In conclusion, NICD was upregulated in human GBM and NICD promoted GBM proliferation via the Notch1 signaling pathway. NICD may be a potential diagnostic marker and therapeutic target for GBM treatment.
Notch细胞内结构域（NICD），也被称为Notch1的激活形式，与细胞分化和肿瘤侵袭密切相关。然而，NICD在胶质母细胞瘤（GBM）增殖中的作用及其潜在调控机制仍不清楚。本研究旨在调查NICD和Notch1下游基因HES5在人GBM和正常脑样本中的表达情况，并进一步检测NICD对人GBM细胞增殖的影响。为此，采用蛋白质印迹法和免疫组织化学染色分析人GBM组织中NICD的表达，同时利用蛋白质印迹法和逆转录定量PCR实验分析人GBM组织中Hes5的表达。使用Flag-NICD载体在U87细胞中过表达NICD，使用化合物E和小干扰（si）Notch1下调NICD。绘制细胞增殖曲线并进行BrdU检测以评估U87细胞的增殖情况。结果表明，与正常脑组织相比，人GBM组织中NICD蛋白水平上调，GBM组织中Hes5的蛋白和mRNA水平也上调，这表明Notch1信号通路在GBM中被激活。NICD的过表达促进了U87细胞的增殖，而用化合物E或siNotch1处理下调NICD则抑制了U87细胞的增殖。总之，NICD在人GBM中上调，并且NICD通过Notch1信号通路促进GBM增殖。NICD可能是GBM治疗的潜在诊断标志物和治疗靶点。
