TF-FVIIa-Xa complex results in thrombin generation. Thrombin is a potent platelet fibrinogen to fibrin, contributing to tumor metastasis. In breast cancer, thrombin acts through protease-activated receptor-1 (PAR-1) receptor and markedly increases growth-related oncogene-alpha (GRO-α) production. Thrombin, PAR activation peptide, and GRO-α all lead to increased production of matrix metalloproteinase (MMP), vascular endothelial growth factor (VEGF), angiopoietin-2 (ANG-2), CD31, and receptors KDR/CXCR-2 in endothelial cells, contributing to tumor growth, angiogenesis, and metastasis. Act. Plts., activated platelets; CXCR2, chemokine receptor for growth-related oncogene-alpha; KDR, kinase insert domain receptor (vascular endothelial growth factor receptor); Plts., platelets.