Platelet receptors implicated in hematogenous tumor metastasis. Schematic representation of platelet surface molecules whose primary functions contribute to hemostasis and coagulation through binding to ligands expressed by other cells or extracellular matrix (ECM) molecules. Modulation of these molecules, for example, through platelet activation, in genetically engineered mice or by antibody-mediated blockade, has been shown in many cases to impact on experimental tumor metastasis.