Lars Bolund

TY - JOUR

T1 - Influence of Lewis alpha1-3/4-L-fucosyltransferase (FUT3) gene mutations on enzyme activity, erythrocyte phenotyping, and circulating tumor marker sialyl-Lewis a levels

AU - Orntoft, T F

AU - Vestergaard, E M

AU - Holmes, Esbern

AU - Jakobsen, J S

AU - Grunnet, N

AU - Mortensen, M

AU - Johnson, P

AU - Bross, P

AU - Gregersen, N

AU - Andresen, Kirsten Skorstengaard

AU - Jensen, Uffe Birk

AU - Bolund, L

AU - Wolf, H

PY - 1996/12/13

Y1 - 1996/12/13

N2 - Fucosylated glycoproteins carrying alpha1-4 fucose residues are of importance for cell adhesion and as tumor markers. The Lewis gene, FUT3, encodes the only known alpha1-4-fucosyltransferase (FucT), and individuals who are deficient in this enzyme type as Lewis-negative on erythrocytes. We examined the mutational spectrum of the Lewis gene in Denmark and found 6 different mutations. Five, T59G, T202C, C314T, G508A, and T1067A, were frequent, and one, C445A, was only detected in one out of 40 individuals. Allele-specific polymerase chain reaction as well as cloning of FUT3 alleles showed that the 202 and 314 mutations were co-located on the same allele. COS7 cells transfected with an allele having the 202/314 mutations lacked enzyme activity. Polymerase chain reaction-cleavage assays were established for the genotyping of healthy individuals as well as 20 genuine Lewis-negative cancer patients and 10 non-genuine. The latter have Lewis-negative erythrocytes but saliva alpha1-4FucT activity. The genuine Lewis-negative individuals had mutations on both FUT3 alleles. In 66 healthy individuals, a gene dosage effect was detected as FUT3 heterozygous individuals had a lower alpha1-4FucT activity in saliva than did homozygous wild-type individuals. The lower enzyme level in heterozygous individuals resulted in a significantly (p <0.04) lower level of circulating sialyl-Lewis a structure in serum. This has the clinical impact that cut-off levels in tumor marker assays should be defined on the basis of genotyping. In the group of non-genuine Lewis-negative cancer patients, whose erythrocytes convert from Lewis-positive to Lewis-negative during the disease, FUT3 heterozygosity was significantly (p <0.05) more common.

AB - Fucosylated glycoproteins carrying alpha1-4 fucose residues are of importance for cell adhesion and as tumor markers. The Lewis gene, FUT3, encodes the only known alpha1-4-fucosyltransferase (FucT), and individuals who are deficient in this enzyme type as Lewis-negative on erythrocytes. We examined the mutational spectrum of the Lewis gene in Denmark and found 6 different mutations. Five, T59G, T202C, C314T, G508A, and T1067A, were frequent, and one, C445A, was only detected in one out of 40 individuals. Allele-specific polymerase chain reaction as well as cloning of FUT3 alleles showed that the 202 and 314 mutations were co-located on the same allele. COS7 cells transfected with an allele having the 202/314 mutations lacked enzyme activity. Polymerase chain reaction-cleavage assays were established for the genotyping of healthy individuals as well as 20 genuine Lewis-negative cancer patients and 10 non-genuine. The latter have Lewis-negative erythrocytes but saliva alpha1-4FucT activity. The genuine Lewis-negative individuals had mutations on both FUT3 alleles. In 66 healthy individuals, a gene dosage effect was detected as FUT3 heterozygous individuals had a lower alpha1-4FucT activity in saliva than did homozygous wild-type individuals. The lower enzyme level in heterozygous individuals resulted in a significantly (p <0.04) lower level of circulating sialyl-Lewis a structure in serum. This has the clinical impact that cut-off levels in tumor marker assays should be defined on the basis of genotyping. In the group of non-genuine Lewis-negative cancer patients, whose erythrocytes convert from Lewis-positive to Lewis-negative during the disease, FUT3 heterozygosity was significantly (p <0.05) more common.

KW - ABO Blood-Group System

KW - Alleles

KW - Animals

KW - Antigens, Tumor-Associated, Carbohydrate

KW - Base Sequence

KW - Blotting, Northern

KW - COS Cells

KW - Erythrocytes

KW - Flow Cytometry

KW - Fucosyltransferases

KW - Humans

KW - Lewis Blood-Group System

KW - Molecular Sequence Data

KW - Mutagenesis

KW - Oligosaccharides

KW - Phenotype

KW - Polymerase Chain Reaction

KW - Rats

KW - Rats, Inbred Lew

KW - Saliva

KW - Transfection

M3 - Journal article

C2 - 8943285

VL - 271

SP - 32260

EP - 32268

JO - Journal of Biological Chemistry

JF - Journal of Biological Chemistry

SN - 0021-9258

IS - 50

ER -