Fig. 2
From: The role of extracellular vesicles in circulating tumor cell-mediated distant metastasis
Role of EVs on CTCs during tumor metastasis. Tumor metastasis via the circulation involves several processes: invasion, intravasation, intravascular survival, extravasation, and secondary site colonization. At the beginning of metastasis, EVs enhance the shedding of CTCs by promoting epithelial-mesenchymal transition (EMT) and extracellular matrix (ECM) remodeling, as well as promoting angiogenesis and increasing vascular permeability; during metastasis, EVs protect CTCs by activating platelets and inducing immunosuppression; finally, EVs determine the metastatic direction of CTCs, participate in the formation of the pre-metastatic niche (PMN) and promote the metastasis and colonization of CTCs. The figure also summarizes the cargoes carried by EVs of different systemic tumor origins (Figure was created with BioRender.com).