Role of exosomes in the invasion and metastasis of PCa. (1) The exosomes secreted by PCa bind to the components of ECM through adhesion receptors and released proteases, which makes the ECM reshape and be hydrolyzed by enzymes. In addition, in PCa, exosomes promote epithelial cells to mesenchymal cells. This allows cancer cells to invade the tissue barrier and metastasize. (2) In PCa, exosomes promote angiogenesis by transferring sphingomyelin and CD147 to endothelial cells; in the case of hypoxia, exosomes promote angiogenesis by promoting the secretion of angiogenic factors. (3) PCa cell-derived exosomes induce the Warburg effect, increase glycolysis rate, and produce lactic acid in stromal cells, leading to cancer progression and invasion. (4) In the tumor microenvironment, cancer cells remodel B cells, T cells, DCs, and NK cells via exosomes to promote tumor progression. EMT, epithelial–mesenchymal transition; FGF, fibroblast growth factor; FGFR, fibroblast growth factor receptor; MMP, matrix metalloproteinase; VEGF, vascular endothelial grown factor; VEGFR, vascular endothelial growth factor receptor.