Uncontrolled endothelial cell proliferation characterizes tumor neovascularization and angioproliferative diseases. Tumor growth is defined by inducement of a new supply of blood. In the control of angiogenesis, the neovascularization process generates new capillary blood vessels, which affects tumor growth and may represent a promising approach to tumor therapy.

Heparan sulfate proteoglycans are involved in the modulation of the neovascularization through the interaction between angiogenic growth factors and/or negative regulators of angiogenesis. The study of the biochemical bases of this interaction may help to design glycosaminoglycan analogs endowed with angiostatic properties.

Pentosan polysulfate binds Fibroblast growth factors (FGF) as well as other heparin-binding factors and it has been shown in vitro to interact with the heparin-binding sites as an effective inhibitor of growth factors, inhibiting the establishment and growth of tumors. Further observations have shown that cultured endothelium is sensitive to inhibition by pentosan polysulfate sodium where microvascular endothelium appears to be most sensitive.
Pentosan polysulfate sodium has been found to inhibit the growth of Kaposi's sarcoma-derived spindle cells in vitro and has been evaluated in phase I/II in advanced cancer and Kaposi’s sarcoma.

Literature

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