1. Department of Neurosurgery, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai 200040, China
2. School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, China
3. Department of Imaging, Dahua Hospital, Xuhui District, Shanghai 200237, China
4. School of Life Science and Technology, Tongji University, Shanghai 200092, China
5. State Key Laboratory of New Drug and Pharmaceutical Process, Shanghai Institute of Pharmaceutical Industry, China State Institute of Pharmaceutical Industry, Shanghai 200437, China
6. Department of medical oncology, Shanghai Changzheng hospital, Second Military Medical University, Shanghai 200003, China
7. Shanghai Geriatric Institute of Chinese Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai 200031, China
* These authors contributed equally to this work and shared the first authorship.
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 Tie1 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, in vivo and in vitro 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 in vivo and in vitro viability of gliomas.
Keywords: Superparamagnetic iron oxide nanoparticles (SPIONs), microRNA, glioma stem cells, Tie1