P-selectin Mediates Adhesion of Leukocytes, Platelets, and Cancer Cells in Inflammation, Thrombosis, and Cancer Growth and Metastasis

Stimulated endothelial cells and activated platelets express P-selectin (CD62P), a member of the selectin family of cell adhesion molecules, which interacts with P-selectin glycoprotein ligand-1 (PSGL-1, CD162) for leukocyte rolling on stimulated endothelial cells and heterotypic aggregation of activated platelets onto leukocytes. Cross-linking of PSGL-1 by P-selectin also primes leukocytes intracellularly for cytokine and chemoattractant-induced beta2-integrin activation for firm adhesion of leukocytes. Furthermore, P-selectin mediates heterotypic aggregation of activated platelets to cancer cells and adhesion of cancer cells to stimulated endothelial cells. Here we provide a comprehensive summary of the functional roles and the biological importance of P-selectin-mediated cell adhesive interactions in the pathogeneses of inflammation, thrombosis, and the growth and metastasis of cancers.