TMP surface proteins and their functions. TMPs are constitutively released from tumors into the circulation. The procoagulant activity of TMPs is mediated by the expression of TF and the exposure of PS on the MP surface. Tumor markers such as MUC-1 can allow for the identification of TMPs in the circulation. Adhesion proteins including P-selectin ligand CD24 and E-selectin ligand CD43 have been proposed to be involved in the binding of TMPs to endothelium and thrombosis sites.^2,69  Delivery of TMP TF to the site of thrombosis can then initiate thrombosis. This diagram is an example of proteins that can be expressed on the surface of TMPs. Protein expression on the surface of TMPs varies with each tumor. FVIIa, factor VIIa.