The invention relates to a method for modulating the growth and/or proliferation of mammalian cells by modulating the physical interaction between platelets (thrombocytes) and the surface of the cells. The invention therefore relates to sulfated polysaccharides, preferably glycosaminoglycans, for use as a medicament for the inhibition of the physical interaction between the cell surface and platelets in the treatment of a medical disorder associated with unwanted cell growth and/or proliferation. In vitro methods for modulating the physical interaction between platelets (thrombocytes) and the surface of the cells in order to modulate cell proliferation are also encompassed by the invention. The invention therefore relates to the inhibition of the interaction between the cell surface and platelets for the inhibition of cell growth, and an enhancement of the interaction between platelets and the surface of the cell in order to enhance cell growth.
