Department of Neurosurgery, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai 200040, China.
School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, China.
Int J Biol Sci. 2020 Feb 10;16(7):1274-1287. doi: 10.7150/ijbs.42887. eCollection 2020.
Gliomas are highly malignant nervous system tumours. Studies shown that cancer stem cells are one of the main reasons underlying recurrence, metastasis, and poor prognosis in glioma cases. Our previous studies have found that superparamagnetic iron oxide nanoparticles (SPIONs) can act as nucleic acid carriers to drive intracellular overexpression of these nucleic acids. In this study, CD44+/CD133+ glioma stem cells (HuGSCs) were first isolated from surgically resected tissues from patients. qPCR and western blot results showed that Tie1 expression in HuGSCs was significantly higher thanexpression in CD44-/CD133- glioma cells. Bioinformatic analysis and luciferase reporter assays showed that miR-485-5p binds to specific loci on the 3'-UTR of mRNA to inhibit Tie1 expression. Subsequently, miR-485-5p/miR-mut and SPION complexes were transfected into HuGSCs. Transmission electron microscopy showed that a highly dense metallic electron cloud is present in HuGSCs. At the same time, and studies showed that miR-485-5p@SPIONs can significantly inhibit HuGSC proliferation, invasion, tumourigenicity, and angiogenesis. In-depth analysis showed that Tie1 interacts with neuronal growth factors such as FGF2, BDNF, GDNF, and GFAP. qPCR and western blot results showed that in miR-485-5p@SPIONs-HuGSCs, the expression levels of Tie1 and stem cell markers (Oct4, Sox2, Nanog, CD44, and CD133), and even FGF2, BDNF, GDNF, and GFAP were significantly lower than thelevels in the control group (miR-mut@SPIONs-HuGSCs). Therefore, this study showedthat Tie1 is an important factor that maintains glioma stem cell activity. SPIONs drive miR-485-5p overexpression in cells and inhibit endogenous Tie1 expression to downregulate the protein expression levels of Fgf2/GDNF/GFAP/BDNF and significantly weaken the and viability of gliomas.
神经胶质瘤是高度恶性的神经系统肿瘤。研究表明，癌症干细胞是导致神经胶质瘤复发、转移和预后不良的主要原因之一。我们之前的研究发现，超顺磁性氧化铁纳米粒子（SPIONs）可以作为核酸载体，驱动这些核酸在细胞内的过表达。在这项研究中，首先从手术切除的患者组织中分离出 CD44+/CD133+神经胶质瘤干细胞（HuGSCs）。qPCR 和 Western blot 结果显示，HuGSCs 中的 Tie1 表达明显高于 CD44-/CD133-神经胶质瘤细胞中的表达。生物信息学分析和荧光素酶报告基因检测表明，miR-485-5p 结合到 mRNA 的 3'-UTR 上的特定位点，抑制 Tie1 的表达。随后，将 miR-485-5p/miR-mut 和 SPION 复合物转染到 HuGSCs 中。透射电子显微镜显示，HuGSCs 中存在高密度的金属电子云。同时，MTT 和 Transwell 实验表明，miR-485-5p@SPIONs 可以显著抑制 HuGSC 的增殖、侵袭、致瘤性和血管生成。深入分析表明，Tie1 与神经生长因子如 FGF2、BDNF、GDNF 和 GFAP 相互作用。qPCR 和 Western blot 结果显示，在 miR-485-5p@SPIONs-HuGSCs 中，Tie1 和干细胞标志物（Oct4、Sox2、Nanog、CD44 和 CD133）的表达水平，甚至 FGF2、BDNF、GDNF 和 GFAP 的表达水平均显著低于对照组（miR-mut@SPIONs-HuGSCs）。因此，本研究表明 Tie1 是维持神经胶质瘤干细胞活性的重要因素。SPIONs 驱动细胞中 miR-485-5p 的过表达，并抑制内源性 Tie1 的表达，从而下调 Fgf2/GDNF/GFAP/BDNF 的蛋白表达水平，并显著减弱神经胶质瘤的 MTT 和 Transwell 活力。
