Endothelial Cell Polarity in Health and Disease

Endothelial cell polarity is fundamental to the organization and function of blood vessels, influencing processes such as angiogenesis, vascular stability, and response to shear stress. This review elaborates on the molecular mechanisms that regulate endothelial cell polarity, focusing on key players like the PAR polarity complex and Rho family GTPases. These pathways coordinate the front–rear, apical–basal and planar polarity of endothelial cells, which are essential for the proper formation and maintenance of vascular structures. In health, endothelial polarity ensures not only the orderly development of blood vessels, with tip cells adopting distinct polarities during angiogenesis, but also ensures proper vascular integrity and function. In disease states, however, disruptions in polarity contribute to pathologies such as coronary artery disease, where altered planar polarity exacerbates atherosclerosis, and cancer, where disrupted polarity in tumor vasculature leads to abnormal vessel growth and function. Understanding cell polarity and its disruption is fundamental not only to comprehending how cells interact with their microenvironment and organize themselves into complex, organ-specific tissues but also to developing novel, targeted, and therapeutic strategies for a range of diseases, from cardiovascular disorders to malignancies, ultimately improving patient outcomes.