<p>Pentosan polysulfate is a polymer of xylose hydrogen sulfate and contains two sulfate groups per carbohydrate monomer. It binds Fibroblast growth factors (FGFs) as well as other heparin-binding growth factors. It has been shown to interact also with the heparin-binding site of FGFR-1. It inhibits the growth of SW13 adrenocortical cells transfected with FGF-4 and tumorigenicity of MCF-7 breast carcinoma cells transfected with FGF-1 or FGF-4.</p>