title: Comprehensive proteome profiling of glioblastoma-derived extracellular vesicles identifies markers for more aggressive disease.
abstract: Extracellular vesicles (EVs) play key roles in glioblastoma (GBM) biology and represent novel sources of biomarkers that are detectable in the peripheral circulation. Despite this notionally non-invasive approach to assess GBM tumours in situ, a comprehensive GBM EV protein signature has not been described. Here, EVs secreted by six GBM cell lines were isolated and analysed by quantitative high-resolution mass spectrometry. Overall, 844 proteins were identified in the GBM EV proteome, of which 145 proteins were common to EVs secreted by all cell lines examined; included in the curated EV compendium (Vesiclepedia_559; http://microvesicles.org ). Levels of 14 EV proteins significantly correlated with cell invasion (invadopodia production; r2> 0.5, p < 0.05), including several proteins that interact with molecules responsible for regulating invadopodia formation. Invadopodia, actin-rich membrane protrusions with proteolytic activity, are associated with more aggressive disease and are sites of EV release. Gene levels corresponding to invasion-related EV proteins showed that five genes (annexin A1, actin-related protein 3, integrin-β1, insulin-like growth factor 2 receptor and programmed cell death 6-interacting protein) were significantly higher in GBM tumours compared to normal brain in silico, with common functions relating to actin polymerisation and endosomal sorting. We also show that Cavitron Ultrasonic Surgical Aspirator (CUSA) washings are a novel source of brain tumour-derived EVs, demonstrated by particle tracking analysis, TEM and proteome profiling. Quantitative proteomics corroborated the high levels of proposed invasion-related proteins in EVs enriched from a GBM compared to low-grade astrocytoma tumour. Large-scale clinical follow-up of putative biomarkers, particularly the proposed survival marker annexin A1, is warranted.
authors: Faculty of Science, School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW, 2006, Australia.
authors: Duthika M
authors: DM
authors: Mallawaaratchy
authors: Discipline of Pathology, Sydney Medical School, The University of Sydney, Sydney, NSW, 2006, Australia.|Brain and Mind Centre, The University of Sydney, Camperdown, NSW, 2050, Australia.
authors: Susannah
authors: S
authors: Hallal
authors: Discipline of Pathology, Sydney Medical School, The University of Sydney, Sydney, NSW, 2006, Australia.|Brain and Mind Centre, The University of Sydney, Camperdown, NSW, 2050, Australia.
authors: Ben
authors: B
authors: Russell
authors: Brain and Mind Centre, The University of Sydney, Camperdown, NSW, 2050, Australia.
authors: Linda
authors: L
authors: Ly
authors: Discipline of Pathology, Sydney Medical School, The University of Sydney, Sydney, NSW, 2006, Australia.|Brain and Mind Centre, The University of Sydney, Camperdown, NSW, 2050, Australia.
authors: Saeideh
authors: S
authors: Ebrahimkhani
authors: Brain and Mind Centre, The University of Sydney, Camperdown, NSW, 2050, Australia.|Department of Neuropathology, Royal Prince Alfred Hospital, Camperdown, NSW, 2050, Australia.
authors: Heng
authors: H
authors: Wei
authors: Faculty of Science, School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW, 2006, Australia.
authors: Richard I
authors: RI
authors: Christopherson
authors: Discipline of Pathology, Sydney Medical School, The University of Sydney, Sydney, NSW, 2006, Australia.|Brain and Mind Centre, The University of Sydney, Camperdown, NSW, 2050, Australia.|Department of Neuropathology, Royal Prince Alfred Hospital, Camperdown, NSW, 2050, Australia.
authors: Michael E
authors: ME
authors: Buckland
authors: Faculty of Science, School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW, 2006, Australia. kim.kaufman@sydney.edu.au.|Brain and Mind Centre, The University of Sydney, Camperdown, NSW, 2050, Australia. kim.kaufman@sydney.edu.au.|Department of Neuropathology, Royal Prince Alfred Hospital, Camperdown, NSW, 2050, Australia. kim.kaufman@sydney.edu.au.
authors: Kimberley L
authors: 0000-0002-7239-039X
authors: KL
authors: Kaufman
mesh_terms: D014408:Biomarkers, Tumor / Q000378:metabolism*; D001932:Brain Neoplasms / Q000378:metabolism* / Q000473:pathology; D045744:Cell Line, Tumor; D000067128:Extracellular Vesicles / Q000378:metabolism* / Q000473:pathology; D005909:Glioblastoma / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D009361:Neoplasm Invasiveness; D020543:Proteome / Q000378:metabolism*; D040901:Proteomics
chemical_list: D014408:Biomarkers, Tumor; D020543:Proteome
keywords: Annexin a1; Exosome; Extracellular vesicle; Glioblastoma; Invadopodia; Proteomics