Exosomes derived from cancer-associated fibroblasts mediate response to cancer therapy.

Cancer-associated fibroblasts (CAFs) are the prominent stromal cell population in the tumor microenvironment (TME), which play an indispensable role in cancer progression and response to therapy. CAFs provide communication between tumor cells and surrounding cells by secreting soluble biomolecules and extracellular vesicles (EVs). Exosomes are small membrane-bound EVs that contain various cargos, including growth factors, non-coding RNAs (ncRNAs), cytokines, and chemokines. These biomolecules can be transferred between cells within the TME and alter the behavior of recipient cells. Some studies have shown that exosomes secreted by CAFs contribute to resistance to chemotherapy and radiotherapy. This review focuses on CAF-derived exosomes in different types of tumors, with emphasis on resistance to chemotherapy and radiotherapy.