Table 1.

Studies employing exosomes without genetic modification for the treatment of cancer.

Exosome Source	Setting	Therapy	Tumour	Study Outcome	Reference
Macrophages (RAW 264.7)	In Vivo	PTX/DOX	Lung Mets	Exosomal PTX preferentially accumulated in cancer cells	[9]
Ascites-derived	Clinical trial	AEX alone or AEX + GM-CSF	Colorectal	AEX + GM-CSF was safe, nontoxic, tolerable, and induced a beneficial tumour-specific anti-tumour CTL response	[14]
Dendritic cells	Clinical trial	MHC Class II peptides	Melanoma	Large scale exosome production was feasible and exosome administration was safe and well tolerated	[15]
Dendritic cells	Clinical trial	MAGE (tumour antigens)	Lung	Therapy well tolerated with some experiencing long term stable disease and activation of immune effectors	[16]
Dendritic cells	In Vivo	IL-4 + GM-CSF	Breast	Eradication/suppression of growth of pre-established tumours in a T-cell dependant manner	[17]
Dendritic cells	In Vivo	MHC Class I	Melanoma	MHC Class I restricted CD8+ T-cell expansion and differentiation	[18]
Dendritic cells	In Vivo	CpG Adjuvant	Melanoma	Combination of exosomes and TLR 3 + 9 triggered efficient MHC-restricted CD8+ T-cell responses	[19]
Dendritic cells	In Vivo	DC-Exo alone	Melanoma	DC-Exo promoted IL-15Rα- and NKG2D-dependent NK cell proliferation and activation which resulted in anti-metastatic effects	[20]
Dendritic cells	In Vitro	DC-Exo alone	Breast	Incorporation of DC-Exo by tumour cells increased ability to activate T-cells for a more effective response	[21]
Brain endothelial cells	In Vivo	rhodamine 123, PTX, DOX	Brain	Exosome delivery allowed DOX and PTX to cross the BBB which resulted in cytotoxicity against U-87 MG cells	[22]

Abbreviations: AEX—Ascites-derived exosomes; GM-CSF—granulocyte-macrophage colony-stimulating factor; CTL—cytotoxic T lymphocyte; PTX—Paclitaxel; Dox—Doxorubicin; IL—Interleukin; MAGE—Melanoma-associated antigen; DC—Dendritic Cell.