The tumor microenvironment (TME) is a unique platform of
cancer biology that considers the local cellular environment in which a
tumor exists. Increasing evidence points to the TME as crucial for either promoting immune
tumor rejection or protecting the
tumor. The TME includes surrounding blood vessels, the extracellular matrix (ECM), a variety of immune and regulatory cells, and signaling factors. Exosomes have emerged to be molecular contributors in
cancer biology, and to modulate and affect the constituents of the TME. Exosomes are small (40-150 nm) membrane vesicles that are derived from an endocytic nature and are later excreted by cells. Depending on the cells from which they originate, exosomes can play a role in
tumor suppression or
tumor progression.
Tumor-derived exosomes (TDEs) have their own unique phenotypic functions. Evidence points to TDEs as key players involved in
tumor growth,
tumorigenesis, angiogenesis, dysregulation of immune cells and immune escape,
metastasis, and resistance to
therapies, as well as in promoting anti-
tumor response. General exosomes, TDEs, and their influence on the TME are an area of promising research that may provide potential
biomarkers for
therapy, potentiation of anti-
tumor response, development of exosome-based
vaccines, and exosome-derived nanocarriers for drugs.