CXCL8 and glioblastoma: Very large amounts of EVs were isolated from the plasma of GBM patients, and it was found that they contain hypoxia-regulated proteins, such as, among others, matrix metalloprotease 9 (MMP9), platelet-derived growth factor (PDGF), interleukin-8 (IL-8), and caveolin 1 (CAV1).