Anti-angiogenic properties of sulfated polysaccharides fucoidans and their analogs

In order to find efficient anticancer agents among natural sulfated polysaccharides and their analogs, we studied the anti-angiogenic capacity of natural fucoidans from brown algae Saccharina latissima (SL) and Chordaria flagelliformis (CF) along with chemically modified fucoidan from Punctaria plantaginea (MF) and synthetic completely sulfated fucooctasaccharide (OS) built of (1 & RARR;3)-bonded residues of alpha-l-fucopyranose of exhibiting anti-angiogenic activity in vitro on the model of formation of capillary-like structures (precapillaries) by endothelial cells or their precursors, mesenchymal stem cells. The activity of the studied compounds was tested on cells of low-grade human breast cancer of the MDA-MB-231 line and multipotent mesenchymal stem cells (MSCs) of dogs. Fucoidan CF and its derivatives SL and MF in a concentration of 0.1 mg mL(-1) reliably suppress the formation of closed circular structures by cancer cells. The formation of capillary-like structures of MSC is inhibited by fucoidan CF in concentrations of 0.1 and 0.01 mg mL(-1). Modified fucoidan MF and synthetic oligosaccharide OS are somewhat less active, which can be due to their insufficiently high molecular weights and specific features of the sulfation character. The obtained data indicate that the search for anti-angiogenic agents in the series of sulfated oligosaccharides with the variation of the molecular size, structure, and sulfation pattern should be extended.