Table 3.

EV PD-L1 as a potential biomarker for tumor diagnosis, progression and treatment

Type of tumor	Biomarker type	Effect	References
Metastatic melanoma	Diagnostic biomarker	Exo-PD-L1 levels in patients is higher than those in healthy controls	[8]
NSCLC	Diagnostic biomarker	Exo-PD-L1 levels patients in is higher than those in healthy controls	[136]
HNSCC	Tumor progression biomarker	The RFV of Exo-PD-L1 in patients with high UICC stage was higher than that in patients with low UICC stage	[124]
NSCLC	Tumor progression biomarker	High levels of Exo-PD-L1 were associated with larger tumor size, positive lymph node status, distant metastasis and advanced TNM stage	[136]
Pancreatic cancer	Tumor progression biomarker	The OS of patients with high Exo-PD-L1 levels was markedly lower	[125]
GC	Tumor progression biomarker	The OS of patients with high Exo-PD-L1 levels was markedly lower	[126]
Osteosarcoma	Tumor progression biomarker	The levels of Exo-PD-L1 were positively correlated larger tumor size	[114]
Glioblastoma	Tumor progression biomarker	Exo-PD-L1 is associated with lung metastasis of osteosarcoma	[146]
Melanoma	The marker of the efficacy of ICB	High levels of Exo-PD-L1 are associated with low response to anti-PD-1 therapy	[8, 147]
NSCLC	The marker of the efficacy of ICB	The level of Exo-PD-L1 was lower in patients with effective anti-PD-1 therapy	[147]