Microvascular Mural Cells in Cancer.

Microvascular mural cells (MMCs) are important regulators of tumor vessel properties, such as endothelial cell differentiation and vessel permeability, and are recognized as modulators of tumor angiogenesis and growth. Emerging experimental studies suggest impact of MMCs on additional aspects of tumor biology, exerted by functionally distinct subsets. These have been shown to control metastasis both in primary tumors and in the premetastatic niche. Other studies link marker-defined MMCs to tumor immune surveillance and drug sensitivity. In parallel, recent efforts to profile MMCs in clinical samples are confirming the existence of clinically relevant marker-defined MMC subsets which show marker- and tumor-type- specific associations with prognosis and response to treatment. Collectively, findings encourage to continued analyses of MMC subsets as candidate biomarkers and drug targets.