The common structural alterations in the
cell-surface glycoproteins concern the highly elevated expression of tri- and tetra-antennary beta1-6-N-acetylglucosamine (beta1-6 GlcNAc) bearing N-
glycans, which are recognised by Phaseolus vulgaris
agglutinin (
PHA-L). In this report we identified
proteins bearing beta1-6 GlcNAc branched N-
glycans in three human
melanoma cell lines: WM35--from the primary tumour site, as well as WM239 and WM9 from different metastatic sites: the skin and the lymph node, respectively, by tandem mass spectrometry (MS/MS) on
PHA-L agarose bound material, followed by immunochemical identification. Our results show that
melanoma cell lines differ from each other in the number of N-
glycoproteins bearing beta1-6 GlcNAc branched
oligosaccharides. Among identified
proteins the largest group consists of
integrin subunits. In addition, L1-CAM, Mac-2
binding protein,
melanoma cell adhesion molecule,
intercellular adhesion molecule,
melanoma associated
antigen, tumour rejection antigen-1,
melanoma-associated
chondroitin sulfate proteoglycan 4 and
lysosome-associated membrane protein (LAMP-1) were found. It was indicated that WM35 cell line showed the lowest number of
proteins possessing beta1-6 GlcNAc branched N-
glycans in comparison to metastatic WM9 and WM239 cell lines. Our data suggest that changes in the number of
proteins being a substrate for GlcNAc-TV are better correlated with
melanoma development and progression than with expression of
cell adhesion molecules.