Platelet contribution to cancer cell growth and migration: The role of platelet growth factors

Blood platelets contain several growth factors and inhibitors. The better known among them are named platelet-derived growth factor (PDGF) and transforming growth factor β (TGFβ), active as modulators of growth of normal mesenchymal and epithelial cells. Cancer cell growth in vitro seems to be independent of the effects of exogenous peptides, but dependent on the cell ability to release autocrine growth factors, similar to PDGF or TGFβ. In addition, platelet-associated growth factors and inhibitors, which are able to induce a Fibrotic response in connective tissue cells, might also play a role to modulate the desmoplastic reaction surrounding the tumor.