Table 2.

Summary of functions of small and large EVs and their identified major component contributing to the response to a systemic therapy.

EV Cargo	Type of EVs	Function	References
Gastric cancer
Multidrug resistance protein	Mesenchymal stem cell-exosomes	Induces the resistance of gastric cancer to 5-fluorouracil by antagonising apoptosis and enhancing the expression of multidrug resistance-associated proteins	[168]
miR-21	Tumour-associated macrophage-exosomes	Reduces chemosensitivity to cisplatin and apoptosis of GC cells by upregulating the PTEN/PI3K/AKT pathway	[176]
miR-155-5p	Cancer cell-exosomes	Resistance of GC cells to paclitaxel via GATA binding protein 3 and tumour protein p53-inducible nuclear protein 1 suppression	[177]
miR-501	Cancer cell-exosomes	Promotes doxorubicin resistance in GC by downregulating BH3-like motif-containing cell death inducer and inactivating apoptosis	[178]
Oesophageal cancer
miR-193	Cancer cell-exosomes	Cisplatin resistance of oesophageal cancer cells	[179]
lncRNA PART1	Cancer cell-exosomes	Induces gefitinib resistance in ESCC by targeting Bcl-2 signalling and inducing the suppression of apoptosis	[180]
Colorectal cancer
miR-21	Fibroblast-exosomes	Resistance to oxaliplatin in CRC cells	[181]
miR-196b-5p	Blood circulating-exosomes	to 5-fluorouracil resistance via activating signal transducer and activator of transcription 3 signalling pathway	[182]
Wnt ligands	Fibroblast-exosomes	Resistance to chemotherapy	[183]
miR-21-5p miR-1246 miR-1229-5p miR-96-5p	Cancer cell-exosomes Blood-circulating-exosomes	Oxaliplatin and 5-fluorouracil resistance	[184]
miR-34 miR-145	Cancer cell-microvesicles	5-fluorouracil resistance	[185]
lncRNA H19	Fibroblast-exosomes	Oxaliplatin resistance via Wnt/β-catenin pathway activation	[186]
p-STAT3	Cancer cell-exosomes	Reduces caspase cascade activation leading to 5-fluorouracil resistance	[187]
HCC
ND	Cancer cell-exosomes	Activates the HGF/c-Met/Akt signalling pathway thus inhibit sorafenib-induced apoptosis	[189]
miR-32-5p	Cancer cell-exosomes	Stimulates the PI3K/Akt pathway of HCC cells, which possess the potential to induce multidrug resistance through angiogenesis and epithelial-mesenchymal transition	[191]
lnRNA ROR	Cancer cell- exosomes	Regulates chemoresistance by reducing cell death in the TGFβ-dependent manner	[192]
miR-122	Cancer cell –exosomes	Reduces the resistance to sorafenib via inhibition of RAS/RAF/ERK signalling	[193]
siGRP78	bone marrow mesenchymal stem cells exosomes	sensitise HCC cells to sorafenib	[195]

ND, not determined; ESCC, oesophageal squamous cell carcinoma; STAT3, Signal transducer and activator of transcription 3.