FIGURE 3.

Schematic illustration of exosome biogenesis, identification, and roles in tumorigenesis, diagnosis, and therapy. This diagram differentiates various types of extracellular vesicles by size and secretion pathways: membrane particles (50–600 nm), microvesicles (100–1,000 nm) originating from the cell surface, and apoptotic bodies (1,000–5,000 nm) from apoptotic cells. Exosomes, derived from multivesicular bodies (MVBs), are depicted as nanoparticles with an average diameter of 40–150 nm. They contain nucleic acids, proteins, lipids, and metabolites, playing crucial roles in intercellular communication. Exosomes influence the tumor microenvironment, aid in tumor formation, and are utilized in blood or urine for early tumor diagnosis. Additionally, they serve as vehicles for targeted cancer therapy.