The role of tumor-derived exosomes in epithelial mesenchymal transition (EMT)

Exosomes are membrane-bound small vesicles (30–150 nm) produced by all cell types and present in all body fluids (1). They are a part of the intercellular communication system that is evolutionarily conserved and operates in bacteria as well as all multicellular organisms (2). Tumor cells produce and release masses of exosomes into the extracellular space. These exosomes carry information in the form of molecular signals and/or genetic materials (mRNA, miRNA, DNA) from the parent tumor cell to locally- or distantly-located recipient cells. Exosome-mediated transfer of information results in re-programming of the recipient cell genome and proteome and ultimately leads to the acquisition of new cellular functions (3).