TF and cancer: These procoagulant factors include the tissue factor (TF), a protein released by endothelial cells, monocytes, and malignant cells; the TF-bearing microparticles (cancer-associated procoagulant proteins that free float in the plasma of oncology patients and also interact with factor X); and the cancer procoagulant, a molecule that has been found only in fetal and malignant tissue.