Specific detection of sialyl Lewis X determinant carried on the mucin GlcNAcbeta1-->6GalNAcalpha core structure as a tumor-associated antigen.
Sialyl Lewis X serves as a ligand for selectins and is proposed to be implicated in hematogenous metastasis of cancers. When a cultured human breast cancer cell line, MCF-7, which does not express sialyl Lewis X, was transfected with human fucosyltransferase VI cDNA, a strong expression of sialyl Lewis X was induced on transfectant cells. The transfectant cells were found to be also reactive to the antibody NCC-ST-439, which was initially raised against human gastric cancer cells and later was shown to recognize a tumor-associated carbohydrate antigen in breast, gastric, and colon cancers. This suggested that the antigen recognized by NCC-ST-439 is closely related to sialyl Lewis X. Subsequent studies indicated that NCC-ST-439 specifically reacts to NeuAcalpha2-->3Galbeta1-->4(Fucalpha1-->3)GlcNAcbet a1-->6GalNAcalpha1 -->R, the sialyl Lewis X on the mucin GlcNAcbeta1-->6 GalNAcalpha structure. The antibody was not reactive to the conventional sialyl Lewis X determinants on straight and/or branched polylactosamine structures including NeuAcalpha2-->3Galbeta1-->4(Fucalpha1-->3)GlcNAcbet a1-->3Galbeta1-->4 Glcbeta1-->R and NeuAcalpha2-->3Galbeta1-->4(Fucalpha1-->3)GlcNAcbet a1-->6Galbeta1-->4 Glcbeta1-->R. This was in clear contrast to most of the known anti-sialyl Lewis X antibodies, which do not discriminate internal structures carrying the sialyl Lewis X determinant. On the other hand, the newly generated monoclonal antibody GSC154-27 had a specificity completely the reverse of the specificity of NCC-ST-439 in that it was strongly reactive to the conventional sialyl Lewis X determinants in straight and branched polylactosamine structures, while far less reactive to the sialyl Lewis X determinant on the mucin GlcNAcbeta1-->6GalNAcalpha core structure. A set of these two antibodies would be useful in discriminating the molecular species of sialyl Lewis X expressed by malignant cells and in studying their functional significance.
Kumamoto
K
K
Program of Experimental Pathology, Aichi Cancer Center, Nagoya, 464-8681, Japan.
Mitsuoka
C
C
Izawa
M
M
Kimura
N
N
Otsubo
N
N
Ishida
H
H
Kiso
M
M
Yamada
T
T
Hirohashi
S
S
Kannagi
R
R
D000911:Antibodies, Monoclonal; D000918:Antibody Specificity; D015295:Antigens, Tumor-Associated, Carbohydrate / Q000737:chemistry*; D001943:Breast Neoplasms / Q000276:immunology / Q000556:secondary; D002240:Carbohydrate Sequence; D002448:Cell Adhesion / Q000276:immunology; D018076:DNA, Complementary / Q000235:genetics; D004187:Disaccharides / Q000737:chemistry* / Q000276:immunology*; D000939:Epitopes / Q000737:chemistry; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D008969:Molecular Sequence Data; D009077:Mucins / Q000737:chemistry* / Q000276:immunology*; D009844:Oligosaccharides / Q000737:chemistry*; D011379:Prognosis; D000080506:Sialyl Lewis X Antigen; D014162:Transfection; D014407:Tumor Cells, Cultured
D000911:Antibodies, Monoclonal; D015295:Antigens, Tumor-Associated, Carbohydrate; D018076:DNA, Complementary; D004187:Disaccharides; D000939:Epitopes; D009077:Mucins; D009844:Oligosaccharides; D000080506:Sialyl Lewis X Antigen; C073214:N-acetylglucosaminyl beta(1-6)N-acetylgalactosamine