In highly malignant brain tumor glioblastoma multiforme (GBM), hypoxic cancer cell-derived exosomes showed enrichment in hypoxia-associated mRNAs and proteins (e.g., matrix metalloproteinases, IL-8, platelet-derived growth factor (PDGF), caveolin 1, and lysyl oxidase) and activated vascular cells in a hypoxia-dependent mode during cancer progression [70]. This evidence concerns the gene CXCL8 and glioblastoma.