Exosomes at a glance - common nominators for cancer hallmarks and novel diagnosis tools.

Cancer represents a heterogeneous disease with multiple levels of regulation and a dynamic environment that sustains the evolution of the malignant mass. This dynamic is in part sustained by a class of extracellular vesicles termed exosomes that are able to imprint the pathological state by incorporating differential cargos in order to facilitate cell-to-cell communication. Exosomes are stable within the extracellular medium and function as shuttles secreted by healthy or pathological cells, being further taken by the accepting cell with direct effects on its phenotype. The exosomal trafficking is deeply involved in multiple levels of cancer development with roles in all cancer hallmarks. Nowadays, studies are constantly exploring the ability of exosomes to sustain the malignant progression in order to attack this pathological trafficking and impair the ability of the tumor mass to expand within the organisms. As important, the circulatory characteristics of exosomes represent a steady advantage regarding the possibility of using them as minimally invasive diagnosis tools, where cancer patients' present modified exosomal profiles compared to the healthy ones. This last characteristic, as novel diagnosis tools, has the advantage of a possible rapid transition within the clinic, compared to the studies that evaluate the therapeutic meaning.