title: Secreted glycoproteins of human kidney tumour cells contain sulphated complex-type oligosaccharides.
abstract: Human kidney tumour cells in culture incorporated [3H]glucosamine and 35SO4 into glycoprotein products, which were secreted into the culture medium. The effects of sodium butyrate, a known differentiation-inducing agent, on the production of these sulphated glycoproteins were studied. Cells were cultured in the absence or presence of butyrate (2 mM) in serum-containing medium, for various times, and the labelled glycoproteins were partially purified by DEAE-cellulose chromatography. Treatment of these cells with butyrate resulted in an increase in the synthesis of secreted [3H]glucosamine- and 35SO4-labelled glycoproteins over several days of culture. This same increase in levels of 35SO4 incorporation was not observed with B16 melanoma cells. Sodium dodecyl sulphate (SDS)/polyacrylamide gel electrophoresis revealed that five major glycoproteins labelled with [3H]glucosamine also were labelled with 35SO4. The major secreted glycoproteins from cells cultured in the absence or presence of butyrate over a 3-day period were similar by SDS/polyacrylamide gel electrophoresis. Analyses of Pronase-derived glycopeptides indicated that these secreted 3H/35S-labelled glycoproteins contained sulphated oligosaccharides with terminal sialic acid----Gal----GlcNAc residues similar to glycoproteins secreted by vascular endothelial cells.
mesh_terms: D002087:Butyrates / Q000494:pharmacology; D020148:Butyric Acid; D002454:Cell Differentiation; D002478:Cells, Cultured; D055598:Chemical Phenomena; D002621:Chemistry; D005944:Glucosamine / Q000378:metabolism; D006023:Glycoproteins / Q000378:metabolism*; D006801:Humans; D007680:Kidney Neoplasms / Q000378:metabolism* / Q000473:pathology; D009363:Neoplasm Proteins / Q000378:metabolism*; D009844:Oligosaccharides / Q000378:metabolism*; D013431:Sulfates / Q000378:metabolism
chemical_list: D002087:Butyrates; D006023:Glycoproteins; D009363:Neoplasm Proteins; D009844:Oligosaccharides; D013431:Sulfates; D020148:Butyric Acid; D005944:Glucosamine