TGFB1 and glioblastoma: In another study, glioblastoma-specific epidermal growth factor receptor vIII (EGFRvIII) was found in serum exosomes from a significant proportion of patients, whereas EGFR, EGFRvIII, and TGF-β were found in serum exosomes from patients with brain tumours, suggesting that they all might provide diagnostic information for glioblastomas and brain tumours respectively [235, 236].