Tumor cell MUC1 and CD43 are glycosylated differently with sialyl-Lewis a and x epitopes and show variable interactions with E-selectin under physiological flow conditions.
The mucins secreted from the colon carcinoma cell line COLO 205 have the MUC1 and CD43 (leukosialin) as core proteins, where both carry sialyl-Lewis a and MUC1 sialyl-Lewis x epitopes. The adhesion of E-selectin expressing CHO cells to the coated mucins was analyzed in a flow system revealing that the MUC1 mucin adhered better than the CD43 mucin. One reason could be their different glycosylation, a difference that was explored by analyzing the biosynthesis of MUC1 and CD43 in COLO 205 cells. Both the MUC1 and CD43 mucins became sialyl-Lewis a reactive, but after different times as revealed by pulse-chase studies. However, only MUC1 became sialyl-Lewis x reactive. These differences suggest that MUC1 and CD43 are synthesized in different compartments of the cell. It was also observed that the mucins from colon carcinoma patients had MUC1-type mucins that carried both sialyl-Lewis a and x epitopes and CD43-type sialyl-Lewis a mucins with only low levels of sialyl-Lewis x epitopes. One could hypothesize that colon carcinoma derived MUC1 is decorated with potent E-selectin epitopes, and that this could be one of several reasons for the involvement of MUC1 in cancer development.
Fernandez-Rodriguez
J
J
Department of Medical Biochemistry, Göteborg University, Box 440, 405 30 Gothenburg, Sweden.
Dwir
O
O
Alon
R
R
Hansson
G C
GC
D000230:Adenocarcinoma / Q000276:immunology* / Q000378:metabolism; D000818:Animals; D015703:Antigens, CD; D018395:CA-19-9 Antigen; D016466:CHO Cells / Q000378:metabolism; D002240:Carbohydrate Sequence; D002448:Cell Adhesion / Q000502:physiology; D003110:Colonic Neoplasms / Q000276:immunology* / Q000378:metabolism; D006224:Cricetinae; D019040:E-Selectin / Q000235:genetics / Q000378:metabolism*; D000939:Epitopes / Q000378:metabolism*; D005732:Gangliosides / Q000276:immunology*; D006031:Glycosylation; D018922:HL-60 Cells / Q000473:pathology; D006801:Humans; D051917:Leukosialin; D008969:Molecular Sequence Data; D018396:Mucin-1 / Q000276:immunology / Q000378:metabolism*; D009844:Oligosaccharides / Q000276:immunology*; D011817:Rabbits; D012795:Sialoglycoproteins / Q000276:immunology / Q000378:metabolism*; D000080506:Sialyl Lewis X Antigen; D013314:Stress, Mechanical; D014407:Tumor Cells, Cultured
D015703:Antigens, CD; D018395:CA-19-9 Antigen; D019040:E-Selectin; D000939:Epitopes; D005732:Gangliosides; D051917:Leukosialin; D018396:Mucin-1; D009844:Oligosaccharides; C465014:SPN protein, human; D012795:Sialoglycoproteins; D000080506:Sialyl Lewis X Antigen; C064564:sialyl Le(a) ganglioside