1. Please check and comment entries here.
Table of Contents

    Topic review

    Extracellular Vesicles in Glioblastoma

    Subjects: Oncology
    View times: 8
    Submitted by: Natalia Simionescu


    Glioblastoma (GB) is the most aggressive form of brain cancer in adults, characterized by poor survival rates and lack of effective therapies. MicroRNAs (miRNAs) are small, non‐coding RNAs that regulate gene expression post‐transcriptionally through specific pairing with target messenger RNAs (mRNAs). Extracellular vesicles (EVs) are cell‐derived vesicles which transport miRNAs, mRNAs and intracellular proteins, and have been shown to promote horizontal malignancy into adjacent tissue, as well as resistance to conventional therapies. Furthermore, GB-derived EVs have distinct miRNA contents and are able to penetrate the blood–brain barrier and could be used as biomarkers, while EVs carrying specific miRNAs or miRNA inhibitors have great potential as therapeutic nanotools in GB.

    1. Overview

    Glioblastoma (GB) is the most aggressive form of brain cancer in adults, characterized by poor survival rates and lack of effective therapies. MicroRNAs (miRNAs) are small, non-coding RNAs that regulate gene expression post-transcriptionally through specific pairing with target messenger RNAs (mRNAs). Extracellular vesicles (EVs), a heterogeneous group of cell-derived vesicles, transport miRNAs, mRNAs and intracellular proteins, and have been shown to promote horizontal malignancy into adjacent tissue, as well as resistance to conventional therapies. Furthermore, GB-derived EVs have distinct miRNA contents and are able to penetrate the blood–brain barrier. Numerous studies have attempted to identify EV-associated miRNA biomarkers in serum/plasma and cerebrospinal fluid, but their collective findings fail to identify reliable biomarkers that can be applied in clinical settings. However, EVs carrying specific miRNAs or miRNA inhibitors have great potential as therapeutic nanotools in GB, and several studies have investigated this possibility on in vitro and in vivo models. In this review, we discuss the role of EVs and their miRNA content in GB progression and resistance to therapy, with emphasis on their potential as diagnostic, prognostic and disease monitoring biomarkers and as nanocarriers for gene therapy.

    2. Glioblastoma

    Glioblastoma (GB) is the most aggressive form of brain cancer in adults, characterized by fast growth and invasiveness, high tumor heterogeneity, poor survival and lack of effective therapies [1][2][3]. The diagnosis and classification of brain tumors have undergone several modifications over the last two decades. Thus, the latest classification of central nervous system (CNS) tumors released by the World Health Organization (WHO) [4] takes into account molecular markers along with histological assessment and clinical presentation into the diagnosis and classification of GB. In this regard, it has been demonstrated that GBs with identical histopathological classification, but of a different molecular subtype, have distinctive clinical outcomes and treatment responses: the Proneural subtype is associated with longer survival and low treatment response compared to other subtypes, while Classical and Mesenchymal subtypes respond significantly better to aggressive treatment [5][6]. Following diagnosis, the current standard of treatment for GB includes maximum safe surgical resection (often aided by 5-aminolevulinic acid (5-ALA)-induced tumor fluorescence), radiotherapy and chemotherapy using temozolomide (TMZ) or other agents [7][8][9][10][11].
    Despite recent therapeutic advances and improved imaging techniques, de novo GB diagnosis is frequently done in advanced stages of the disease, when the impact on patients’ quality of life is severe. Furthermore, recurring GB tumors are still difficult to manage, and magnetic resonance imaging (MRI) follow-ups are expensive and sometimes misleading, as it is difficult to distinguish between recurrence and pseudo progression. Despite ongoing efforts to develop new diagnostic and therapeutic tools, minimal advances have been made, and no reliable biomarkers are being used in clinical practice [12]. Therefore, there is a need for minimally invasive, easy to measure and cost-effective biomarkers for early diagnosis of GB and therapeutic response monitoring. The advancements in molecular biology in the last decades have led to the discovery of new potential biomarkers, among which microRNAs (miRNAs) seem to be the most promising ones.
    MiRNAs are small, single-stranded, non-coding RNAs that regulate gene expression post-transcriptionally by inhibiting translation and/or promoting messenger RNA (mRNA) degradation through specific pairing with target mRNAs [13]. MiRNAs are stress response molecules, have modified expression levels during disease progression and are known to be involved in the initiation and development of various types of cancer [14][15]. Furthermore, miRNAs have been shown to circulate in the blood stream and cerebrospinal fluid (CSF), associated with extracellular vesicles (EVs), lipoproteins or protein complexes, and their circulating profiles reflect their modified tissue expression or an increased intercellular communication [16][17]. This, combined with the fact that miRNAs are relatively easy to measure in biological fluids, supports their potential use as biomarkers for diagnosis, prognosis and therapeutic response monitoring of CNS malignancies. However, many studies have attempted to identify specific serum or CSF miRNAs as biomarkers for brain tumors, including GB [18], but their collective findings fail to identify reliable biomarkers that can be applied in clinical settings. Serum biomarkers are easy to measure and can be useful in clinical practice, but EVs have a more disease- and tissue-specific cargo and could differentiate between pathologies more accurately.
    EVs represent a heterogenous group of lipid vesicles that are secreted by numerous cell types, under physiological or pathological conditions, exhibit specific markers and transport particular molecules from their cells of origin, including miRNAs [19][20][21][22][23][24]. Furthermore, EVs bind and fuse with their target cells, delivering their cargo and promoting horizontal malignancy into adjacent tissues [23][25], as well as resistance to therapeutic interventions [26][27][28][29][30][31]. On the other hand, EVs derived from healthy cells have been shown to improve pathological conditions in recipient cells [32][33][34]. Considering the ability of miRNAs to target multiple transcripts, EV-mediated transfer of miRNAs to recipient cells could have an extensive impact.
    EVs can be isolated from biological fluids [35][36][37][38][39][40][41][42] or cell culture medium [43], providing an extensive platform for studying pathological processes. Moreover, EVs have been shown to contain a significantly distinct miRNA signature compared to their cells of origin, suggesting a selective miRNA packaging into EVs [24], and their number and miRNA content change under pathological conditions [23][44][45]. These aspects could be exploited in a clinical setting as EVs have been shown to have diagnostic potential in various pathologies, including GB [26][46], as well as biomarker potential for treatment response monitoring and disease recurrence [47][48][49][50][51][52].
    Due to the ability of EVs to cross the blood–brain barrier [53][54] and to transfer their cargo to a wide array of cells [23][25][32][33][34], they could be used as therapeutic tools in GB. This possibility opens up many new avenues in cancer treatment, aided by the fact that EVs can be enriched in endogenous [55] or synthetic miRNAs [56], or miRNA inhibitors [57][58]. The production and clinical use of EV-based therapeutics depend on numerous safety, biological and manufacturing aspects and are still not clearly regulated [59]. Despite current limitations and drawbacks, EV-based miRNA nanocarriers could represent an important adjuvant in GB therapy, combined with the current standard of treatment.

    3. Conclusions

    Despite recent advancements in diagnostic techniques, GB diagnosis is frequently done in advanced stages of the disease. There is a need for minimally invasive, easy to measure and cost-effective biomarkers for early diagnosis and therapeutic response monitoring of GB. The research data obtained in the last decades has led to the discovery of new potential biomarkers, among which miRNAs seem to be the most promising ones. Moreover, there is increasing evidence that EV-associated miRNAs may provide a more specific discrimination between studied cohorts and, therefore, could have great diagnostic and prognostic value. However, these biomarkers have not been yet introduced in clinical practice due to great differences between studies. In order to identify reliable biomarkers, larger studies with well characterized cohorts of patients need to be undertaken.
    Furthermore, EV-based miRNA nanocarriers can be taken into consideration as adjuvants in GB therapy, combined with the current standard of treatment.

    The entry is from 10.3390/pharmaceutics13070988


    1. Patel, A.P.; Tirosh, I.; Trombetta, J.J.; Shalek, A.K.; Gillespie, S.M.; Wakimoto, H.; Cahill, D.P.; Nahed, B.V.; Curry, W.T.; Martuza, R.L.; et al. Single-cell RNA-seq highlights intratumoral heterogeneity in primary glioblastoma. Science 2014, 344, 1396–1401.
    2. Zong, H.; Verhaak, R.G.W.; Canolk, P. The cellular origin for malignant glioma and prospects for clinical advancements. Expert Rev. Mol. Diagn. 2012, 12, 383–394.
    3. Lathia, J.D.; Heddleston, J.M.; Venere, M.; Rich, J.N. Deadly teamwork: Neural cancer stem cells and the tumor microenvironment. Cell Stem Cell 2011, 8, 482–485.
    4. Louis, D.N.; Perry, A.; Reifenberger, G.; von Deimling, A.; Figarella-Branger, D.; Cavenee, W.K.; Ohgaki, H.; Wiestler, O.D.; Kleihues, P.; Ellison, D.W. The 2016 World Health Organization Classification of Tumors of the Central Nervous System: A summary. Acta Neuropathol. 2016, 131, 803–820.
    5. Verhaak, R.G.W.; Hoadley, K.A.; Purdom, E.; Wang, V.; Qi, Y.; Wilkerson, M.D.; Miller, C.R.; Ding, L.; Golub, T.; Mesirov, J.P.; et al. Integrated Genomic Analysis Identifies Clinically Relevant Subtypes of Glioblastoma Characterized by Abnormalities in PDGFRA, IDH1, EGFR, and NF1. Cancer Cell 2010, 17, 98–110.
    6. Brennan, C.W.; Verhaak, R.G.W.; McKenna, A.; Campos, B.; Noushmehr, H.; Salama, S.R.; Zheng, S.; Chakravarty, D.; Sanborn, J.Z.; Berman, S.H.; et al. The somatic genomic landscape of glioblastoma. Cell 2013, 155, 462–477.
    7. Munteanu, R.M.; Eva, L.; Dobrovăţ, B.I.; Iordache, A.C.; Pendefunda, L.; Dumitrescu, N.; Mihăilă, D.; Gavrilescu, C.M.; Şapte, E.; Poeată, I. Longer survival of a patient with glioblastoma resected with 5-aminolevulinic acid (5-ALA)-guided surgery and foreign body reaction to polyglycolic acid (PGA) suture. Rom. J. Morphol. Embryol. 2017, 58, 671–680.
    8. Hanif, F.; Muzaffar, K.; Perveen, K.; Malhi, S.M.; Simjee, S.U. Glioblastoma multiforme: A review of its epidemiology and pathogenesis through clinical presentation and treatment. Asian Pac. J. Cancer Prev. 2017, 18, 3–9.
    9. Stupp, R.; Hegi, M.E.; Mason, W.P.; van den Bent, M.J.; Taphoorn, M.J.; Janzer, R.C.; Ludwin, S.K.; Allgeier, A.; Fisher, B.; Belanger, K.; et al. Effects of radiotherapy with concomitant and adjuvant temozolomide versus radiotherapy alone on survival in glioblastoma in a randomised phase III study: 5-year analysis of the EORTC-NCIC trial. Lancet Oncol. 2009, 10, 459–466.
    10. Reardon, D.A.; Wen, P.Y. Therapeutic Advances in the Treatment of Glioblastoma: Rationale and Potential Role of Targeted Agents. Oncologist 2006, 11, 152–164.
    11. Weller, M.; van den Bent, M.; Preusser, M.; Le Rhun, E.; Tonn, J.C.; Minniti, G.; Bendszus, M.; Balana, C.; Chinot, O.; Dirven, L.; et al. EANO guidelines on the diagnosis and treatment of diffuse gliomas of adulthood. Nat. Rev. Clin. Oncol. 2021, 18, 170–186.
    12. Weller, M.; van den Bent, M.; Tonn, J.C.; Stupp, R.; Preusser, M.; Cohen-Jonathan-Moyal, E.; Henriksson, R.; Rhun, E.L.; Balana, C.; Chinot, O.; et al. European Association for Neuro-Oncology (EANO) guideline on the diagnosis and treatment of adult astrocytic and oligodendroglial gliomas. Lancet Oncol. 2017, 18, e315–e329.
    13. Bartel, D.P. MicroRNAs: Genomics, Biogenesis, Mechanism, and Function. Cell 2004, 116, 281–297.
    14. Hayes, J.; Peruzzi, P.P.; Lawler, S. MicroRNAs in cancer: Biomarkers, functions and therapy. Trends Mol. Med. 2014, 20, 460–469.
    15. Areeb, Z.; Stylli, S.S.; Koldej, R.; Ritchie, D.S.; Siegal, T.; Morokoff, A.P.; Kaye, A.H.; Luwor, R.B. MicroRNA as potential biomarkers in Glioblastoma. J. Neurooncol. 2015, 125, 237–248.
    16. Vickers, K.C.; Remaley, A.T. Lipid-based carriers of microRNAs and intercellular communication. Curr. Opin. Lipidol. 2012, 23, 91–97.
    17. Gareev, I.F.; Novicova, L.B.; Beylerli, O.A. Circulating MicroRNA as Novel Potential Biomarkers for the Diagnosis of Highly Malignant Gliomas. Neurosci. Behav. Physiol. 2020, 50, 283–287.
    18. Petrescu, G.E.D.; Sabo, A.A.; Torsin, L.I.; Calin, G.A.; Dragomir, M.P. MicroRNA based theranostics for brain cancer: Basic principles. J. Exp. Clin. Cancer Res. 2019, 38, 231.
    19. Doyle, L.; Wang, M. Overview of Extracellular Vesicles, Their Origin, Composition, Purpose, and Methods for Exosome Isolation and Analysis. Cells 2019, 8, 727.
    20. Alexandru, N.; Badila, E.; Weiss, E.; Cochior, D.; Stępień, E.; Georgescu, A. Vascular complications in diabetes: Microparticles and microparticle associated microRNAs as active players Dedicated to the 150th anniversary of the Romanian Academy. Biochem. Biophys. Res. Commun. 2016, 472, 1–10.
    21. Jurj, A.; Zanoaga, O.; Braicu, C.; Lazar, V.; Tomuleasa, C.; Irimie, A.; Berindan-Neagoe, I. A comprehensive picture of extracellular vesicles and their contents. Molecular transfer to cancer cells. Cancers 2020, 12, 298.
    22. Al-Nedawi, K.; Meehan, B.; Micallef, J.; Lhotak, V.; May, L.; Guha, A.; Rak, J. Intercellular transfer of the oncogenic receptor EGFRvIII by microvesicles derived from tumour cells. Nat. Cell Biol. 2008, 10, 619–624.
    23. Skog, J.; Würdinger, T.; van Rijn, S.; Meijer, D.H.; Gainche, L.; Curry, W.T.; Carter, B.S.; Krichevsky, A.M.; Breakefield, X.O. Glioblastoma microvesicles transport RNA and proteins that promote tumour growth and provide diagnostic biomarkers. Nat. Cell Biol. 2008, 10, 1470–1476.
    24. Collino, F.; Deregibus, M.C.; Bruno, S.; Sterpone, L.; Aghemo, G.; Viltono, L.; Tetta, C.; Camussi, G. Microvesicles derived from adult human bone marrow and tissue specific mesenchymal stem cells shuttle selected pattern of miRNAs. PLoS ONE 2010, 5, e11803.
    25. Chen, X.; Liang, H.; Zhang, J.; Zen, K.; Zhang, C.Y. Horizontal transfer of microRNAs: Molecular mechanisms and clinical applications. Protein Cell 2012, 3, 28–37.
    26. Chistiakov, D.A.; Chekhonin, V.P. Extracellular vesicles shed by glioma cells: Pathogenic role and clinical value. Tumor Biol. 2014, 35, 8425–8438.
    27. Yin, J.; Zeng, A.; Zhang, Z.; Shi, Z.; Yan, W.; You, Y. Exosomal transfer of miR-1238 contributes to temozolomide-resistance in glioblastoma. EBioMedicine 2019, 42, 238–251.
    28. Zeng, A.; Wei, Z.; Yan, W.; Yin, J.; Huang, X.; Zhou, X.; Li, R.; Shen, F.; Wu, W.; Wang, X.; et al. Exosomal transfer of miR-151a enhances chemosensitivity to temozolomide in drug-resistant glioblastoma. Cancer Lett. 2018, 436, 10–21.
    29. Munoz, J.L.; Walker, N.D.; Mareedu, S.; Pamarthi, S.H.; Sinha, G.; Greco, S.J.; Rameshwar, P. Cycling quiescence in temozolomide resistant glioblastoma cells is partly explained by microRNA-93 and -193-mediated decrease of cyclin D. Front. Pharmacol. 2019, 10, 134.
    30. Xiao, S.; Yang, Z.; Lv, R.; Zhao, J.; Wu, M.; Liao, Y.; Liu, Q. MiR-135b contributes to the radioresistance by targeting GSK3βb in Human glioblastoma multiforme cells. PLoS ONE 2014, 9, e108810.
    31. Yue, X.; Lan, F.; Xia, T. Hypoxic Glioma Cell-Secreted Exosomal miR-301a Activates Wnt/β-catenin Signaling and Promotes Radiation Resistance by Targeting TCEAL7. Mol. Ther. 2019, 27, 1939–1949.
    32. Alexandru, N.; Andrei, E.; Niculescu, L.; Dragan, E.; Ristoiu, V.; Georgescu, A. Microparticles of healthy origins improve endothelial progenitor cell dysfunction via microRNA transfer in an atherosclerotic hamster model. Acta Physiol. 2017, 221, 230–249.
    33. Xu, H.; Zhao, G.; Zhang, Y.; Jiang, H.; Wang, W.; Zhao, D.; Hong, J.; Yu, H.; Qi, L. Mesenchymal stem cell-derived exosomal microRNA-133b suppresses glioma progression via Wnt/β-catenin signaling pathway by targeting EZH2. Stem Cell Res. Ther. 2019, 10, 381.
    34. Qiu, G.; Zheng, G.; Ge, M.; Wang, J.; Huang, R.; Shu, Q.; Xu, J. Mesenchymal stem cell-derived extracellular vesicles affect disease outcomes via transfer of microRNAs. Stem Cell Res. Ther. 2018, 9, 320.
    35. Akers, J.C.; Ramakrishnan, V.; Yang, I.; Hua, W.; Mao, Y.; Carter, B.S.; Chen, C.C. Optimizing preservation of extracellular vesicular miRNAs derived from clinical cerebrospinal fluid. Cancer Biomark. 2016, 17, 125–132.
    36. Liu, Z.; Cauvi, D.M.; Bernardino, E.M.A.; Lara, B.; Lizardo, R.E.; Hawisher, D.; Bickler, S.; De Maio, A. Isolation and characterization of human urine extracellular vesicles. Cell Stress Chaperones 2018, 23, 943–953.
    37. Yuan, Z.; Bedi, B.; Sadikot, R.T. Bronchoalveolar lavage exosomes in lipopolysaccharide-induced septic lung injury. J. Vis. Exp. 2018.
    38. Arraud, N.; Linares, R.; Tan, S.; Gounou, C.; Pasquet, J.M.; Mornet, S.; Brisson, A.R. Extracellular vesicles from blood plasma: Determination of their morphology, size, phenotype and concentration. J. Thromb. Haemost. 2014, 12, 614–627.
    39. Zonneveld, M.I.; Brisson, A.R.; van Herwijnen, M.J.C.; Tan, S.; van de Lest, C.H.A.; Redegeld, F.A.; Garssen, J.; Wauben, M.H.M.; Nolte-t’Hoen, E.N.M. Recovery of extracellular vesicles from human breast milk is influenced by sample collection and vesicle isolation procedures. J. Extracell. Vesicles 2014, 3, 24215.
    40. Höög, J.L.; Lötvall, J. Diversity of extracellular vesicles in human ejaculates revealed by cryo-electron microscopy. J. Extracell. Vesicles 2015, 4, 28680.
    41. Iwai, K.; Yamamoto, S.; Yoshida, M.; Shiba, K. Isolation of Extracellular Vesicles in Saliva Using Density Gradient Ultracentrifugation. Methods Mol. Biol. 2017, 1660, 340–353.
    42. Ebert, B.; Rai, A.J. Isolation and characterization of amniotic fluid-derived extracellular vesicles for biomarker discovery. In Methods in Molecular Biology; Humana Press: Totowa, NJ, USA, 2019; Volume 1885, pp. 287–294.
    43. Palviainen, M.; Saari, H.; Kärkkäinen, O.; Pekkinen, J.; Auriola, S.; Yliperttula, M.; Puhka, M.; Hanhineva, K.; Siljander, P.R.M. Metabolic signature of extracellular vesicles depends on the cell culture conditions. J. Extracell. Vesicles 2019, 8, 1596669.
    44. André-Grégoire, G.; Bidère, N.; Gavard, J. Temozolomide affects Extracellular Vesicles Released by Glioblastoma Cells. Biochimie 2018, 155, 11–15.
    45. Blandford, S.N.; Galloway, D.A.; Moore, C.S. The roles of extracellular vesicle microRNAs in the central nervous system. Glia 2018, 66, 2267–2278.
    46. Alexandru, N.; Costa, A.; Constantin, A.; Cochior, D.; Georgescu, A. Microparticles: From Biogenesis to Biomarkers and Diagnostic Tools in Cardiovascular Disease. Curr. Stem Cell Res. Ther. 2016, 12, 89–102.
    47. Akers, J.C.; Ramakrishnan, V.; Kim, R.; Skog, J.; Nakano, I.; Pingle, S.; Kalinina, J.; Hua, W.; Kesari, S.; Mao, Y.; et al. miR-21 in the Extracellular Vesicles (EVs) of Cerebrospinal Fluid (CSF): A Platform for Glioblastoma Biomarker Development. PLoS ONE 2013, 8, e78115.
    48. Shi, R.; Wang, P.Y.; Li, X.Y.; Chen, J.X.; Li, Y.; Zhang, X.Z.; Zhang, C.G.; Jiang, T.; Li, W.B.; Ding, W.; et al. Exosomal levels of miRNA-21 from cerebrospinal fluids associated with poor prognosis and tumor recurrence of glioma patients. Oncotarget 2015, 6, 26971–26981.
    49. Santangelo, A.; Imbrucè, P.; Gardenghi, B.; Belli, L.; Agushi, R.; Tamanini, A.; Munari, S.; Bossi, A.M.; Scambi, I.; Benati, D.; et al. A microRNA signature from serum exosomes of patients with glioma as complementary diagnostic biomarker. J. Neurooncol. 2018, 136, 51–62.
    50. Zhong, F.; Huang, T.; Leng, J. Serum miR-29b as a novel biomarker for glioblastoma diagnosis and prognosis. Int. J. Clin. Exp. Pathol. 2019, 12, 4106–4112.
    51. Tabibkhooei, A.; Izadpanahi, M.; Arab, A.; Zare-Mirzaei, A.; Minaeian, S.; Rostami, A.; Mohsenian, A. Profiling of novel circulating microRNAs as a non-invasive biomarker in diagnosis and follow-up of high and low-grade gliomas. Clin. Neurol. Neurosurg. 2020, 190, 105652.
    52. Li, Z.; Ye, L.; Wang, L.; Quan, R.; Zhou, Y.; Li, X. Identification of miRNA signatures in serum exosomes as a potential biomarker after radiotherapy treatment in glioma patients. Ann. Diagn. Pathol. 2020, 44, 151436.
    53. Morad, G.; Carman, C.V.; Hagedorn, E.J.; Perlin, J.R.; Zon, L.I.; Mustafaoglu, N.; Park, T.E.; Ingber, D.E.; Daisy, C.C.; Moses, M.A. Tumor-Derived Extracellular Vesicles Breach the Intact Blood-Brain Barrier via Transcytosis. ACS Nano 2019, 13, 13853–13865.
    54. Saint-Pol, J.; Gosselet, F.; Duban-Deweer, S.; Pottiez, G.; Karamanos, Y. Targeting and Crossing the Blood-Brain Barrier with Extracellular Vesicles. Cells 2020, 9, 851.
    55. Fareh, M.; Almairac, F.; Turchi, L.; Burel-Vandenbos, F.; Paquis, P.; Fontaine, D.; Lacas-Gervais, S.; Junier, M.P.; Chneiweiss, H.; Virolle, T. Cell-based therapy using miR-302-367 expressing cells represses glioblastoma growth. Cell Death Dis. 2017, 8, e2713.
    56. Lee, H.K.; Finniss, S.; Cazacu, S.; Bucris, E.; Ziv-Av, A.; Xiang, C.; Bobbitt, K.; Rempel, S.A.; Hasselbach, L.; Mikkelsen, T.; et al. Mesenchymal stem cells deliver synthetic microRNA mimics to glioma cells and glioma stem cells and inhibit their cell migration and self-renewal. Oncotarget 2013, 4, 346–361.
    57. Munoz, J.L.; Bliss, S.A.; Greco, S.J.; Ramkissoon, S.H.; Ligon, K.L.; Rameshwar, P. Delivery of functional anti-miR-9 by mesenchymal stem cell-derived exosomes to glioblastoma multiforme cells conferred chemosensitivity. Mol. Ther. Nucleic Acids 2013, 2, e126.
    58. Monfared, H.; Jahangard, Y.; Nikkhah, M.; Mirnajafi-Zadeh, J.; Mowla, S.J. Potential therapeutic effects of exosomes packed with a miR-21-sponge construct in a rat model of glioblastoma. Front. Oncol. 2019, 9, 782.
    59. Lener, T.; Gimona, M.; Aigner, L.; Börger, V.; Buzas, E.; Camussi, G.; Chaput, N.; Chatterjee, D.; Court, F.A.; del Portillo, H.A.; et al. Applying extracellular vesicles based therapeutics in clinical trials—An ISEV position paper. J. Extracell. Vesicles 2015, 4, 30087.