Fucosylated chondroitin sulfate from the sea cucumber Hemioedema spectabilis: Structure and influence on cell adhesion and tubulogenesis

•Structure of a new fucosylated chondroitin sulfate HeSp was determined.•The sea cucumber Hemioedema spectabilis was the source of HeSp.•HeSp was composed of sulfated di- and trisaccharide blocks.•HeSp effectively inhibited cancer cells adhesion to platelet-coated surface.•HeSp prevented tubulogenesis more effectively than heparin. Fucosylated chondroitin sulfate (FCS) HeSp was isolated from the Patagonian sea cucumber Hemioedema spectabilis. Ion-exchange chromatography was applied for purification of the FCS from the crude extract of sulfated polysaccharides. Analysis of monosaccharide and sulfate content of HeSp revealed the molar ratio of GlcA:GalNAc:Fuc:SO3Na as 1.15:1:1.1:3.9. Molecular weight of HeSp (44.1 kDa) was determined by GPC. According to the NMR spectral data, the main fragment of HeSp was the trisaccharide →3)-β-d-GalNAc-(1→4)-β-d-GlcA(3-O-α-l-Fuc)-(1→, where GalNAc units were sulfated either at O-4, at O-6 or both at O-4 and O-6. The fucosyl branches attached to O-3 of GlcA showed also different patterns of sulfation: Fucp2S4S, Fucp4S and Fucp3S4S were found in a ratio of 3.8:1.5:1. Besides, small amounts of the disaccharide fragment →3)-β-d-GalNAc-(1→4)-β-d-GlcA3S-(1→ were observed in a structure of HeSp. The polysaccharide was found to block cancer cells adhesion to platelet-coated surface and to inhibit tubulogenesis, thus demonstrating the potential antitumor activity.