Wang Chongwu, Wang Zhaotao, Chen Chen, Fu Xiaojun, Wang Ji, Fei Xiaowei, Yan Xiaojing, Xu Ruxiang
The 7th Medical center of Chinese PLA general hospital, Chinese PLA General Hospital Afflicted the Seventh Medical Center, Beijing, China.
Department of Neurosurgery, The Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, China.
Br J Pharmacol. 2020 Jul;177(13):3009-3023. doi: 10.1111/bph.15030. Epub 2020 Apr 5.
As a hallmark of glioblastoma multiforme (GBM), CD44 plays a crucial role in promoting glioblastoma stem cell (GSC) stemness phenotypes and multiple drug resistance. The therapeutic potential of CD44 has been validated by the clinical successes of several CD44 inhibitors, including antibodies and hyaluronan-related drugs.
We used systemsDock software to predict verbascoside as a candidate CD44 inhibitor. Microscale thermophoresis was used to confirm the interaction between CD44 and verbascoside. Four glioblastoma cell lines and a patient-derived glioblastoma cell line were used to test the influences of verbascoside on glioblastoma. CD44-overexpressing and CD44-knockout cell lines were also used. Real-time quantitative PCR and western blot analyses were performed. A xenograft mouse model was used to test verbascoside.
Verbascoside bound to CD44 and suppressed its dimerization. By inhibiting CD44 dimerization, verbascoside decreased the release of the CD44 intracellular domain (CD44ICD) and suppressed the expression of CD44 downstream genes. Verbascoside treatment suppressed the stemness phenotypes of cells with high CD44 expression. In a mouse model of glioma, verbascoside treatment highly reduced the growth of intracranial tumours and inhibited CD44ICD release. Both stem cell marker and mesenchymal GBM subtype marker genes were down-regulated in verbascoside-treated mice.
Verbascoside suppressed growth of glioblastoma cells by inhibiting CD44 dimerization. Stem cell-like cell properties and tumour cell growth were also suppressed by verbascoside, both in vitro and in vivo. Verbascoside significantly prolonged survival of xenografted mice.
作为多形性胶质母细胞瘤（GBM）的一个标志，CD44在促进胶质母细胞瘤干细胞（GSC）干性表型和多药耐药性方面发挥着关键作用。几种CD44抑制剂（包括抗体和透明质酸相关药物）的临床成功验证了CD44的治疗潜力。
我们使用SystemsDock软件预测毛蕊花糖苷为候选CD44抑制剂。采用微量热泳动技术确认CD44与毛蕊花糖苷之间的相互作用。使用四种胶质母细胞瘤细胞系和一种患者来源的胶质母细胞瘤细胞系来测试毛蕊花糖苷对胶质母细胞瘤的影响。还使用了CD44过表达和CD44敲除细胞系。进行了实时定量PCR和蛋白质印迹分析。使用异种移植小鼠模型来测试毛蕊花糖苷。
毛蕊花糖苷与CD44结合并抑制其二聚化。通过抑制CD44二聚化，毛蕊花糖苷减少了CD44细胞内结构域（CD44ICD）的释放，并抑制了CD44下游基因的表达。毛蕊花糖苷处理抑制了高CD44表达细胞的干性表型。在胶质瘤小鼠模型中，毛蕊花糖苷处理显著降低了颅内肿瘤的生长并抑制了CD44ICD的释放。在毛蕊花糖苷处理的小鼠中，干细胞标志物和间充质GBM亚型标志物基因均下调。
毛蕊花糖苷通过抑制CD44二聚化抑制胶质母细胞瘤细胞的生长。在体外和体内，毛蕊花糖苷还抑制了干细胞样细胞特性和肿瘤细胞生长。毛蕊花糖苷显著延长了异种移植小鼠的生存期。
