N-glycoproteins bearing beta1-6 branched oligosaccharides from the A375 human melanoma cell line analysed by tandem mass spectrometry.
Tumour-associated alterations of cell surface glycosylation play a crucial role in the adhesion and metastasis of cancer cells. It is well known that the metastatic potential is associated with increased GlcNAc beta1-6 branching in N-glycans of tumour cells specifically recognized by a lectin from Phaseolus vulgaris leukoagglutinin (PHA-L). We identified proteins bearing GlcNAc beta1-6 branched N-glycans in the A375 human melanoma cell line by affinity chromatography separation on a PHA-L agarose column, followed by immunoidentification and tandem mass spectrometry (MS/MS) analysis. Amongst the proteins identified were integrin subunits alpha2, alpha3, alpha5 and beta1, as well as N-cadherin and lysosome-associated membrane proteins (LAMP-1 and LAMP-2). In addition, L1, Mac-2 binding protein (Mac-2-BP), activated leukocyte cell adhesion molecule/CD166 (ALCAM) and melanotransferrin were shown to react with PHA-L. Some of these proteins are connected mainly with nervous tissues or the immune system and play a crucial role in cell adhesion processes. The presence of GlcNAc beta1-6 branched oligosaccharides in these proteins may influence their adhesion properties, reducing adhesion of the cells to the extracellular matrix (ECM) and thus facilitating tumour cell invasion.
Ochwat
Danuta
D
Laboratory for Glycobiology, Institute of Zoology, Department of Animal Physiology, Jagiellonian University, Ingardena 6, 30-060 Kraków, Poland.
Hoja-Łukowicz
Dorota
D
Lityńska
Anna
A
D020410:Activated-Leukocyte Cell Adhesion Molecule / Q000378:metabolism; D015703:Antigens, CD / Q000378:metabolism; D000951:Antigens, Neoplasm; D014408:Biomarkers, Tumor; D015820:Cadherins / Q000378:metabolism; D002352:Carrier Proteins / Q000378:metabolism; D002448:Cell Adhesion; D002846:Chromatography, Affinity; D006023:Glycoproteins / Q000378:metabolism*; D006031:Glycosylation; D006801:Humans; D039421:Integrin alpha2 / Q000378:metabolism; D039482:Integrin alpha5 / Q000378:metabolism; D019012:Integrin beta1 / Q000378:metabolism; D051907:Lysosomal Membrane Proteins; D008545:Melanoma / Q000378:metabolism*; D009363:Neoplasm Proteins / Q000378:metabolism*; D025942:Oligosaccharides, Branched-Chain / Q000378:metabolism*; D027805:Phaseolus; D010835:Phytohemagglutinins / Q000378:metabolism; D010940:Plant Proteins / Q000378:metabolism; D012878:Skin Neoplasms / Q000378:metabolism*; D021241:Spectrometry, Mass, Electrospray Ionization; D014407:Tumor Cells, Cultured; D016326:Extracellular Matrix Proteins
D020410:Activated-Leukocyte Cell Adhesion Molecule; D015703:Antigens, CD; D000951:Antigens, Neoplasm; D014408:Biomarkers, Tumor; D015820:Cadherins; D002352:Carrier Proteins; D006023:Glycoproteins; D039421:Integrin alpha2; D039482:Integrin alpha5; D019012:Integrin beta1; D051907:Lysosomal Membrane Proteins; D009363:Neoplasm Proteins; D025942:Oligosaccharides, Branched-Chain; D010835:Phytohemagglutinins; D010940:Plant Proteins; C081856:LGALS3BP protein, human; D016326:Extracellular Matrix Proteins; C100156:leukoagglutinins, plants; C101135:phytohemagglutinin L protein, Phaseolus vulgaris