Cell biology of tissue factor, an unusual member of the cytokine receptor family

Tissue factor (TF) is a 47-kDa transmembrane protein, involved in the onset of coagulation. However, it also influences pathophysiological processes such as inflammation and tumor angiogenesis. Although the molecular mechanisms responsible for these phenomena remain unclear, it is thought that they are brought about by the action of intracellular signaling, resulting in gene transcription and subsequent protein synthesis. In this review we focus on FVIIa/TF-induced intracellular signaling and its possible role in physiology.