Aberrant α1→2Fucosyltransferases Found in Human Colorectal Carcinoma Involved in the Accumulation of Le^b and Y Antigens in Colorectal Tumors

Abstract

Evidence indicates that the presence of aberrant α1→2fucosylation pathways is responsible for the accumulation of large quantities of Leb and Y antigens in human colorectal carcinoma. Significantly higher activities of α1→2 as well as α1→3 and α1→4fucosyltransferases were found in most of the tissues from carcinoma than in the adjacent normal tissues and in healthy subjects. α1→2Fucosyl‐transferases associated with the synthesis of Leb (Fucal→2Galβ1→3[Fucc1→4]GlcNAcβ) and Y (Fucα1→2Ga1β→4[Fucα1→3]GlcNAcβ) structures from Le→ (GaIβ1→3[Fucal→4]GlcNAcβ) and X (Galβ1→4[Fucα 1→3]GlcNAcβ) ones, respectively, were demonstrated in colorectal carcinomas and in colorectal carcinoma cell lines (COLO201, LS174T and SW1116). The activation of α1→2fucosyltransferase with such new substrate specificities in colorectal carcinoma might result in the preferential synthesis of Leb and Y structures from Le→ and X rather than from H type 1 and H type 2 structures.

Novel Helicobacter pylori α1,2-fucosyltransferase, a key enzyme in the synthesis of Lewis antigens

“…Here, we show that H. pylori α1,2-FucT is functional in the synthesis of both Le b and Le Y , and the synthetic pathways (Fig. 4) are similar to those found in some human cancer cells or tissues (Blaszczyk-Thurin et al, 1988 ;Yazawa et al, 1993) (Fig. 1b, unusual pathway).…”

“…1a) are synthesized through sequential action of the α1,2-and α1,3\4-FucTs through H determinants (Avent, 1997 ;Watkins, 1995). However, unusual α1,2-FucT activity that synthesizes Le b from Le a or Le Y from Le X has been found in some human cancer cells or tissues (Blaszczyk-Thurin et al, 1988 ;Yazawa et al, 1993), and recently such an unusual (the third type) α1,2-FucT was also found in the normal cells of rabbit (Hitoshi et al, 1996).…”

β‐1,3‐galactosyltransferase and α‐1,2‐fucosyltransferase involved in the biosynthesis of type‐1‐chain carbohydrate antigens in human colon adenocarcinoma cell lines

“…Further studies are thus necessary to help establish the enzymes involved in Le b biosynthesis in tumor tissues from non-secretor individuals. The possibility that Le b biosynthesis in non-secretors takes place via A1,2 fucosylation of Le a has been proposed [23], and the authors suggested the existence of an, as yet unidentified, aberrant, A1,2FT in cancer cells [23]. A recent report proposed that such Le a acting activity is Fuc-TIII in COLO-205 cells [38].…”

Molecular Cloning and Expression of a Third Type of Rabbit GDP-L-Fucose:β-D-Galactoside 2-α-L-Fucosyltransferase

“…These phenotypes, which are virtually absent in Caucasians, are thought to be caused by weak Se-type ␣1,2-fucosyltransferase activity. The molecular basis of weak Secretor phenotypes, whether weak Se-type ␣1,2-fucosyltransferase is encoded by an altered Se gene or a gene other than H and Se, has yet to be determined.Recently, aberrant ␣1,2-fucosyltransferase activity, which synthesized Le b from Le a or Le y from the Le x determinant, or both, was found in cancer cells and tissues, suggesting the possibility of a third distinct ␣1,2-fucosyltransferase gene (13,14). In the rabbit, the possibility of a third type of ␣1,2-fucosyltransferase was suggested by immunohistochemical studies on DRG neurons.…”

“…Recently, aberrant ␣1,2-fucosyltransferase activity, which synthesized Le b from Le a or Le y from the Le x determinant, or both, was found in cancer cells and tissues, suggesting the possibility of a third distinct ␣1,2-fucosyltransferase gene (13,14). In the rabbit, the possibility of a third type of ␣1,2-fucosyltransferase was suggested by immunohistochemical studies on DRG neurons.…”