By contrast, platelets do not participate in the generation of the fibrin–fibronectin matrix in tumors, whereas tumor cells are able to secrete several factors with virtually identical functions as those released from platelets, including platelet-derived growth factors (PDGFs), VEGF, transforming growth factor beta (TGF-beta), and fibroblast growth factor 2 (FGF-2) [167,168,169]. This evidence concerns the gene FN1 and neoplasm.