Another one, described by Yokota et al., identified PAR1 signaling on both tumor and host cells as a contributor to metastasis in hyperthrombotic mice; the authors indicate that procoagulant activity of tissue factor (TF) plays a crucial role in successful metastasis by improving intravascular tumor cell survival through fibrin formation, platelet activation and platelet-dependent protection from natural killer cell attack [44]. Here, F3 is linked to neoplasm.