PSAP and glioblastoma: Of the many interesting proteins resolved, A2M, ALDOA, CLU, CTSA, FABP5, GGH, MVP, MYOF, S100-A11, PSAP, VDAC1 warrant specific mention as they were identified in at least two comparative analyses here and were previously identified as GBM-EV biomarkers in other biofluids (Table 2) [3, 5, 40].