Both angiopoietin-1 in serum sEVs and the monocyte differentiation antigen CD14 in serum increased their levels at the pre-symptomatic stage of GBM (T1) and at the later symptomatic stage (T2); thrombospondin 1 was only detected at increased levels in serum sEVs at the symptomatic stage. Here, THBS1 is linked to glioblastoma.