Pathogenesis of human
cancers bridges intracellular oncogenic driver events and their impact on intercellular communication. Among multiple mediators of this 'pathological connectivity' the role of extracellular vesicles (EVs) and their subsets (exosomes, ectosomes, oncosomes) is of particular interest for several reasons. The release of EVs from
cancer cells represents a unique mechanism of regulated expulsion of bioactive molecules, a process that also mediates cell-to-cell transfer of
lipids,
proteins, and
nucleic acids. Biological effects of these processes have been implicated in several aspects of
cancer-related pathology, including tumour growth, invasion, angiogenesis,
metastasis, immunity and
thrombosis. Notably, the emerging evidence suggests that oncogenic mutations may impact several aspects of EV-mediated cell-cell communication including: (i) EV release rate and
protein content; (ii) molecular composition of
cancer EVs; (iii) the inclusion of oncogenic and mutant macromolecules in the EV cargo; (iv) EV-mediated release of genomic
DNA; (v) deregulation of mechanisms responsible for EV biogenesis (vesiculome) and (vi) mechanisms of EV uptake by
cancer cells. Intriguingly, EV-mediated intercellular transfer of mutant and oncogenic molecules between subpopulations of
cancer cells, their indolent counterparts and stroma may exert profound biological effects that often resemble (but are not tantamount to) oncogenic transformation, including changes in cell growth, clonogenicity and angiogenic phenotype, or cause cell stress and death. However, several biological barriers likely curtail a permanent horizontal transformation of normal cells through EV-mediated mechanisms. The ongoing analysis and targeting of EV-mediated intercellular communication pathways can be viewed as a new therapeutic paradigm in
cancer, while the analysis of oncogenic cargo contained in EVs released from
cancer cells into biofluids is being developed for clinical use as a
biomarker and companion diagnostics. Indeed, studies are underway to further explore the multiple links between molecular causality in
cancer and various aspects of cellular vesiculation.