GPC1 and cancer: reported circulating sEVs carrying PD‐L1 were associated with disease progression in head and neck squamous cell carcinoma patients whereas soluble PD‐L1 in plasma was not.[19] Similarly, evidence has shown that serum sEV protein GPC1 from pancreatic cancer patients has absolute specificity and sensitivity to distinguish healthy controls, demonstrating that it is a reliable biomarker for the detection of early‐stage of pancreatic cancer.[20] These data support the concept that sEV protein biomarkers hold potential in cancer early diagnosis and progression stratification.