Resumen
Therapeutic functions of mesenchymal stroma-/stem-like cells (MSCs) are mediated predominantly through paracrine effects by the release of various different components. Upon recruitment of MSCs to damaged tissue sites or tumors, several bioactive molecules and organelles that are secreted by MSCs among others are cytokines, chemokines, metabolites, and extracellular vesicles including exosomes. The MSC-mediated cargo of released exosomes contains specific proteins and nucleic acids with varying regulatory microRNAs according to the tissue origin and the MSC microenvironment. These MSC-released exosomes are taken up by different target cells in damaged tissues to promote a regulatory network of tissue repair, including immune modulation and induction of angiogenesis. Conversely, in tumors, MSC-derived exosomes can confer predominant signals to suppress neovascularization and to relay further tumor-inhibitory effects. However, MSCs that adapted to the tumor tissue by mutual interaction with cancer cells progressively alter to an aberrant phenotype with the release of exosomes carrying tumor-supportive material.