Department of Biochemistry, Sasaki Institute, 22, Kanda-Surugadai, Chiyoda-ku, Tokyo 1010062, and CREST (Core Research for Evolutional Science and Technology) of the Japan Science and Technology Corporation, and 2Second Department of Pathology, Kagoshima University School of Medicine, 8351, Sakuragaoka, Kagoshima 8908520, Japan
Received on February 9, 1999; revised on March 5, 2000; accepted on March 13, 2000.
![]() |
Abstract |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
Key words: sulfotransferase/adenocarcinoma/mucinous carcinoma/ carcinoembryonic antigen/sulfomucin
![]() |
Introduction |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
We previously determined the structure of N-linked glycans in carcinoembryonic antigens (CEA) from foci of liver metastases and the counterpart glycoprotein in normal colonic mucosa, normal fecal antigen-2 (NFA-2) (Yamashita et al., 1987; Fukushima et al., 1995
). The content of GlcNAc-6-O-sulfate residues was consistently found to be
40% in the sugar chains released from five NFA-2 samples. On the other hand, the content of sulfated glycans in two CEA samples was much lower (10%) than that in the case of NFA-2, and the content of sulfated glycans in one CEA sample, in contrast, was much higher (50%) (Fukushima et al., 1995
). These results led us to speculate that human colon tissues have at least two GlcNAc:
6sulfotransferases. Because CEA is a tumor-associated glycoprotein containing 5060%(w/w) of N-linked sugar chains (Yamashita and Kobata, 1996
) and because it has been suggested that CEA may be involved in cell-to-cell interaction as an adhesion molecule (Benchimol et al., 1989
), it seemed important to study the GlcNAc:
6SulT expressed in the course of human colonic carcinogenesis in order to clarify the role of the glycan chains in the biological functions of CEA.
In this study, we examined the biochemical characteristics of GlcNAc:6SulT in human colonic adenocarcinomas and the adjacent normal mucosa. As a result, we found that one type of SulT activity is expressed at a lower level in non-mucinous adenocarcinomas than in the adjacent normal mucosa, and, moreover, that another type of GlcNAc:
6SulT occurs in mucinous adenocarcinomas and adenocarcinomas with a mucinous component.
![]() |
Results |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
|
After digestion, the [35S]-labeled digestion products were applied to a PVL-Sepharose column. PVL is a lectin that recognizes nonsubstituted ß-GlcNAc or ß-GlcNAc substituted at the C-6 position, but it does not bind to ß-GlcNAc substituted at the C-3 or C-4 position (Kochibe and Matta, 1989). A fraction of the [35S]-labeled digestion products bound to the PVL-Sepharose column and was eluted with 0.3 M GlcNAc (Figure 2A), indicating the incorporation of [35S]sulfate at the C-6 position of GlcNAc residues. Rechromatography of the pass-through fraction did not show any radioactivity in the bound and sequential eluent with 0.3M GlcNAc. The [35S]-labeled product in the pass-through fraction in Figure 2 was 3'-O-[35S]sulfo-Galß1
3GalNAc
-pNP, because the [35S]-labeled product was retarded on a MAL-Sepharose column (data not shown), which recognizes SO3
3Galß1
3GalNAc as well as Neu5Ac
2
3Galß1
4GlcNAc3. Gal:
3SulT activities were reported to be present in human normal colon and colon cancer (Kuhns et al., 1995
; Chandrasekaran et al., 1997
).
|
Biochemical properties of SulT-a and SulT-b
In the enzymatic reactions of SulT-a and SulT-b, sulfated products increased linearly for at least 1.5 hr, or up to a protein concentration of 2.0 mg/ml (data not shown). We examined the effects of pH (Figure 3A,B), divalent cations (Figure 3C,D), and detergent (Figure 3E,F) on SulT-a and SulT-b. The optimum pH for activity was 6.88.2 in each instance (Figure 3A,B). The profiles of pH dependency were similar, but SulT-a showed higher activity in cacodylate buffer (pH 5.536.81) than SulT-b. In the presence of 1020 mM MnCl2, the levels of SulT-a and SulT-b activity increased 2.8- and 3.5~4-fold, respectively (Figure 3C, D, solid circles). MgCl2 and CaCl2 had no effect on the activity of these enzymes (Figure 3C, D, open circles and solid triangles, respectively). Chelation of divalent cations by addition of EDTA did not decrease the activity of these enzymes. These results indicate that MnCl2 has a positive effect on the activity of both types of SulT, but is not essential for their activity.
|
Substrate specificities of SulT-a and SulT-b
Next, we examined the acceptor substrate specificities of SulT-a and SulT-b. As shown in Figure 3, G and H, SulT-a recognized core 2 as a good substrate and, to a lesser extent, GlcNAcß12Man. In contrast, SulT-b recognized core 2, core 3, GlcNAcß1
2Man, and GlcNAcß1
3Galß1
4Glc as good substrates. Interestingly, in the case of both types of SulT, the activity decreased at higher concentrations of these acceptor substrates. Table II shows the relative levels of activity of the SulTs derived from non-mucinous adenocarcinomas (cases 3, 10, 13), mucinous adenocarcinomas (cases 29, 34), adenocarcinomas with a mucinous component (case 33), and their adjacent normal mucosa. The relative level of SulT activity in the adjacent mucosa, that of SulT-a, was similar in various specimens, regardless of the histological character of the colon cancer; these GlcNAc:
6SulTs preferentially act on core 2 oligosaccharide and, to a lesser extent, GlcNAcß1
2Man. Core 3 oligosaccharide was not recognized at all by the GlcNAc:
6SulT in normal mucosa. The relative level of SulT activity in non-mucinous adenocarcinomas was similar to that in the adjacent mucosa. In contrast, the GlcNAc:
6SulT derived from mucinous adenocarcinomas or adenocarcinomas with a mucinous component, SulT-b, showed different behavior. SulT-b efficiently acted on GlcNAcß1
3Galß1
4Glc and core 3, as well as core 2 and GlcNAcß1
2Man. We estimated the Michaelis constants (Km) of SulT-a and SulT-b for these substrates based on data obtained at low concentrations (Table III). The Km values of SulT-b for GlcNAcß1
2Man, core 3, GlcNAcß1
3Galß1
4Glc, or core 2 were 1.5, 0.27, 0.42, and 0.28 mM, respectively, and those of SulT-a for GlcNAcß1
2Man or core 2 were 7.7 and 0.30 mM, respectively. The Km values of SulT-a and b for PAPS using core 2 as the acceptor substrate were the same (4 µM).
|
|
|
Difference in GlcNAc:6SulT activities between adenocarcinomas and the adjacent mucosa
As described above, the difference in substrate specificity between SulT-a and SulT-b is especially clear in the behavior with core 3 as the acceptor substrate; SulT-b recognizes core 3 well, whereas SulT-a does not recognize it at all. In view of these characteristics, we assayed the GlcNAc:6SulT activity in all of the membrane fractions listed in Table I using GlcNAcß1
2Man and core 3 as acceptor substrates. As summarized in Table V and Figure 4, (1) in the case of the non-mucinous adenocarcinomas, the levels of GlcNAc:
6SulT activity with GlcNAcß1
2Man as the acceptor substrate were significantly lower in adenocarcinomas than in the adjacent mucosa (1.5 ± 0.27 pmol/min/mg protein in adenocarcinomas on average and 4.0 ± 0.52 pmol/min/mg protein in the adjacent mucosa, p < 0.0002) (Figure 4A). Except for a few specimens, GlcNAc:
6SulT activity was not detected with core 3 as the acceptor substrate (Figure 4C, Table V). (2) In the case of mucinous adenocarcinomas and adenocarcinomas with a mucinous component (Table I and Figure 1), conversely, the levels of activity with GlcNAcß1
2Man as the acceptor substrate were significantly higher in the adenocarcinomas than in the adjacent mucosa (6.1 ± 1.7 pmol/min/mg protein in adenocarcinomas and 2.1 ± 0.56 pmol/min/mg protein in the adjacent mucosa, p < 0.05) (Figure 4B). The occurrence of SulT-b in the adenocarcinomas might contribute to the rather high levels of GlcNAc:
6SulT activity with GlcNAcß1
2Man in the adenocarcinomas, because SulT-b can efficiently act on GlcNAcß1
2Man as well as core 3 (see Table II). SulT activity was not detected in any specimens of adjacent mucosa with core 3 as substrate, but this activity was detected in almost all of these adenocarcinomas (4.6 ± 1.3 pmol/min/mg protein in adenocarcinomas, p < 0.002) (Figure 4D). These results indicate that SulT-b occurs at a high frequency in mucinous adenocarcinomas and adenocarcinomas with a mucinous component, regardless of the proportion of the specimen occupied by the mucinous area as determined microscopically, and that SulT-b is scarcely detected in non-mucinous adenocarcinomas or the adjacent mucosa (Figure 4C).
|
|
|
![]() |
Discussion |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
Colonic mucinous carcinomas are defined by WHO as those in which at least 50% of the area evaluated microscopically is covered with mucus (Morson and Sobin, 1990). We should point out that in this study SulT-b activity was detected not only in the mucinous adenocarcinomas (cases 30, 35, 36) but also in the adenocarcinomas with a mucinous component. These phenomena suggest that it is necessary to carefully examine the differences in biochemical characteristics when comparing mucinous adenocarcinomas and those with a mucinous component.
Moreover, the levels of SulT activity in the mucosa adjacent to non-mucinous adenocarcinomas (4.0 ± 0.52 pmol/min/mg protein on average) were found to be significantly (p < 0.03) higher than those in the mucosa adjacent to mucinous adenocarcinomas (2.1 ± 0.56 pmol/min/mg protein on average), using GlcNAcß12Man as the acceptor substrate (Figure 4). It seems that two possibilities may explain the result. (1) The mucosa adjacent to non-mucinous carcinomas may differ biochemically from that adjacent to mucinous carcinomas, although there appears to be no difference in the pathological features of the mucosa adjacent to these two types of adenocarcinomas. (2) Among the specimens examined, about half of the mucinous adenocarcinomas and about half of those with a mucinous component were present in the ascending colon. The levels of SulT-a activity in the ascending colon might be lower than those in the sigmoid colon and rectum. Further experiments are needed to clarify this matter. We are now searching for other biochemical and histochemical differences between the non-mucinous adenocarcinomas and those with a mucinous component.
This study suggests that the levels of SulT-a and SulT-b activity are correlated with the content of GlcNAc-6-O-sulfate residues in NFA-2 and CEA(Yamashita et al., 1987; Fukushima et al., 1995
). The N-glycans containing GlcNAc-6-O-sulfate residues in CEA molecules may modify the biological properties of the CEA molecules including the cell-to-cell or cell-to-virus/bacteria recognition properties.
We showed that SulT-b has a broader substrate specificity than SulT-a; core 3 and GlcNAcß13Galß1
4Glc are poor acceptor substrates for SulT-a, but good ones for SulT-b. It has been unclear whether or not the core 3 structure exists substantially in O-linked glycans of mucins produced by mucinous adenocarcinomas. Yang et al. (1994)
showed that the levels of enzymatic activity of UDP-GlcNAc:GalNAc-R ß3N-acetylglucosaminyltransferase which synthesizes O-glycan core 3, decrease in cases of colon cancer. Accordingly, it seems necessary to determine the structure of the O-linked, sulfated glycans of mucin-type glycoproteins derived from mucinous adenocarcinoma tissue in the near future.
It has been reported that the abundance of sulfomucins decreases in the course of colonic carcinogenesis (Felipe, 1969; Yamori et al., 1987
). Kuhns et al. (1995)
showed that the level of Gal:
3SulT activity is lower in the case of colon cancer than in normal colonic tissue, indicating that the level of Gal:
3SulT activity reflects the abundance of sulfomucins. Recently, it has been determined that 3'-sulfo-Lewisa is an antigenic determinant on sulfomucins, and expression of this determinant is also decreased in adenocarcinomas (Matsushita et al., 1995
; Loveless et al., 1998
). Although a quantitative difference in the content of 6-O-sulfated GlcNAc in O-linked glycans between normal mucosa and adenocarcinomas has not yet been reported, downregulation of SulT-a might also contribute to the decrease in abundance of sulfomucins in the course of colonic carcinogenesis.
GlcNAc:6SulTs activities have been identified and characterized in rat stomach (Carter et al., 1988
), rat corpus (Goso and Hotta, 1993
), rat liver (Spiro et al., 1996
), human respiratory mucosa (Degroote et al., 1997
), and porcine lymph nodes (Bowman et al., 1998
). Recently, cDNAs for three GlcNAc:
6SulTs have been cloned (Uchimura et al., 1998a
,b; Bistrup et al., 1999
; Hiraoka et al., 1999
; Lee et al., 1999
). The SulT derived from rat liver seems to be different from our colonic SulTs; for example, in terms of the dependencies on divalent cations and pH. The rat liver SulT activity is completely inhibited by EDTA, and the optimal pH region is narrower than that of the SulT-a and SulT-b characterized in this study (Spiro et al., 1996
). In terms of substrate specificity, the rat liver SulT can act on GlcNAcß1
2Man and GlcNAcß1
6Man
1-O-Me, but not on GlcNAcß1
3Galß1
4Glc at all (Spiro et al., 1996
), whereas the human respiratory SulT can act on sialylated core 2 oligosaccharide, but not GlcNAcß1
3GalNAcol (Degroote et al., 1997
). A high content of 6-O-sulfated GlcNAc residues in core 2 oligosaccharides is observed in respiratory mucins derived from cystic fibrosis patients (Lo-Guidice et al., 1994
), indicating that the SulT in the respiratory mucosa may recognize core 2 oligosaccharide as a good acceptor. Uchimura et al. (1998b)
isolated cDNA for a GlcNAc:
6SulT and showed that there is no difference in the amount of the corresponding mRNA expressed in human normal colonic mucosa as compared to adenocarcinomas. Hiraoka et al. (1999)
showed that another GN:SulT, LSST, preferentially acts on core 2 O-glycans, catalyzing their sulfation in vivo, although LSST is unable to act on these oligosaccharides in vitro. We found that the substrate specificity of the GlcNAc:
6SulT reported by Uchimura et al. is similar to that of SulT-a (K.Uchimura, A.Seko, K.Yamashita, and T.Muramatsu, unpublished observations).
More recently, Lee et al. (1999) isolated cDNA for a GlcNAc:
6SulT, expression of which is highly restricted to small intestine and colon. Considering that SulT-b activity can not be detected in normal colon and small intestine (data not shown), SulT-b is an enzyme different from the three GlcNAc:
6SulTs so far cloned, and probably different from the rat liver SulT. Accordingly, since several GlcNAc:
6SulTs showing different enzymatic properties exist in various tissues, it may be necessary to investigate the enzymological properties of these SulTs in detail.
Colonic SulTs have a unique dependency on detergents (Figure 3E,F); digitonin or a low concentration of CHAPS increases the enzymatic activity, whereas n-octyl-ß-D-glucopyranoside and taurodeoxycholate inhibit these SulTs. These results suggest that the condition of solubilization strongly affects the efficiency of catalysis of each of the two SulTs. Since several groups have reported that phospholipids can activate the enzymatic activity of glycosyltransferases, including oligosaccharyltransferase (Chalifour and Spiro, 1988), ß1
4galactosyltransferase (Mitranic et al., 1983
),
2
3sialyltransferase (Westcott et al., 1985
), and glucuronyltransferase (Zakim et al., 1988
; Terayama et al., 1998
), it seems that colonic GlcNAc:
6SulTs may also require a certain lipid cofactor.
It has been proposed that 6-sulfo-3'-sialyl Lewis x is a ligand for L-selectin on the endothelial cells of high endothelial venules (Hemmerich et al., 1995; Sanders et al., 1996
; Mitsuoka et al., 1998
). The initial step in biosynthesis of this glycan is sulfation of the C-6 position of ß-GlcNAc by GlcNAc:
6SulT, and the following galactosylation seems to be catalyzed by GlcNAc-6-O-sulfate:ß1
4GalT which we recently found (Seko et al., 1998
). In cases of colon cancer, 6-sulfo-3'-sialyl Lewis x is expressed on the mucous epithelial cells surrounding differentiated adenocarcinoma tissues (Kannagi et al., 1999
). Although the biological role of this glycan moiety in colon cancer still remains unclear, this glycan moiety may be involved in tumor metastasis or growth of cancer cells. Identification of the SulT-a and SulT-b genes may contribute to clarification of the biological roles of sulfated glycans in colon cancer.
![]() |
Materials and methods |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
Normal mucosal tissue was obtained from an area 10 cm distant from the margin of the carcinoma, and it was separated completely from the muscle layer. The carcinoma tissue was obtained from the surface portion of the carcinoma which was rich in carcinoma cells and had little interstitial tissue.
Chemicals and enzymes
GlcNAcß12Man, GlcNAcß1
3GalNAc
1-p-nitrophenyl (pNP) (core 3), and Galß1
3(GlcNAcß1
6)GalNAc
1-pNP (core 2) were obtained from Funakoshi Co., Ltd. (Tokyo, Japan). GlcNAcß1
3Galß1
4Glc was prepared from lacto-N-tetraose (Kobata, 1972
) by digestion with Streptococcus 6646K ß-galactosidase (Seko et al., 1996
). GlcNAcß1
2Man
1
3(GlcNAcß1
2Man
1
6)Manß1
4GlcNAcß1
4GlcNAc was prepared from egg yolk SGP (Seko et al., 1997
) by mild acid hydrolysis and ß-galactosidase digestion. 3'-Phosphoadenosine-5'-phospho[35S]sulfate ([35S]PAPS, 91.8 GBq/mmol) was purchased from DuPont/NEN (Boston, MA). 3-[(3-Cholamidopropyl)dimethylammonio]-1-propanesulfonate (CHAPS) and sodium taurodeoxycholate were purchased from Sigma (St. Louis, MO). Triton X-100, N-tris[hydroxymethyl]methyl-3-aminopropanesulfonic acid (TAPS), and N-(2-hydroxyethyl)piperazine-N'-2-ethanesulfonic acid (HEPES) were purchased from Nacalai Tesque (Kyoto, Japan). n-Octyl-ß-D-glucopyranoside was obtained from Dojindo Laboratories (Kumamoto, Japan). Digitonin was obtained from Wako Pure Chemical Industries Ltd. (Osaka, Japan). Psathyrella velutina lectin (PVL) was prepared according to the method described previously (Kochibe and Matta, 1989
) and the lectin was conjugated to CNBr-activated Sepharose 4B (Pharmacia) according to the manufacturers recommendations. Bio-Rad Protein Assay dye reagent was obtained from Bio-Rad Laboratories (Richmond, CA).
Preparation of microsomes from human colonic tissues
The microsome preparation procedures were described previously (Seko et al., 1996). Briefly, tissues (0.10.3 g) were immersed in 9 volumes of 10 mM HEPES-NaOH buffer (pH 7.2), 0.25 M sucrose at 4°C, homogenized with a Potter-Elvehjem type homogenizer, and then centrifuged. The extraction was further performed twice and the three supernatant fractions were mixed and ultracentrifuged at 100,000 x g for 1 hr. The precipitated microsomes were suspended in 20 mM HEPES-NaOH buffer (pH 7.2) and kept at 80°C until use.
Assay of GlcNAc:6SulT
A 20 µl reaction mixture consisting of 0.1 M HEPES-NaOH (pH 7.4), 0.1% (w/v) digitonin, 10 mM MnCl2, 0.1 M NaF, 2 mM ATP-Na2, 1 mM acceptor substrate, 6.5 µM [35S]PAPS (2.8 x 105 dpm), and microsomes appropriately diluted, was incubated at 37°C for 1.5 h. The [35S]-labeled products were purified by paper electrophoresis. The Rf values of [35S]-labeled GlcNAcß12Man, [35S]-labeled core 2, and PAPS are 0.90, 0.59, and 1.89, respectively, when the Rf value of bromophenol blue is taken as 1.0. After extraction with water, the [35S]-labeled products using core 2 as substrate were first digested with jack bean ß-N-acetylhexosaminidase (1 unit; 37°C for 16 h, 100 µl of 0.1 M citrate-phosphate buffer pH 6.0) and then applied to PVL-Sepharose column (2 mg/ml; 0.35 x 2.5 cm). Elution was started with 6 ml of 10 mM Tris-HCl (pH 8), 0.15 M NaCl, 1 mM CaCl2, 1 mM MgCl2, followed by the same buffer containing 0.3 M GlcNAc.
Determination of protein concentrations
The protein concentrations in the preparations of microsomes employed were estimated using the Bio-Rad Protein Assay dye reagent with bovine serum albumin as a standard.
Hydrazinolysis-nitrous acid deamination of [35S]sulfated products
This was performed as reported by Edge and Spiro (1984). [35S]Sulfated oligosaccharides were de-N-acetylated by hydrazinolysis at 100°C for 24 h, and then deaminated by treatment with 0.2 M NaNO2 in 0.5 N acetic acid at room temperature for 2 h. After the deaminated fragments were reduced with NaBH4, the sulfated fragments were analyzed by thin layer chromatography (TLC) in the solvent, ethyl acetate/pyridine/acetic acid/water = 5:5:1:3 or 1-butanol/pyridine/water = 6:4:3. Authentic 2,5-anhydro-6-sulfo-[3H]mannitol was prepared as described previously (Fukushima et al., 1995
).
![]() |
Acknowledgments |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
![]() |
Abbreviations |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
![]() |
Footnotes |
---|
![]() |
References |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
Bistrup,A., Bhakta,S., Lee,J.K., Belov,Y.Y., Gunn,M.D., Zuo,F.-R., Huang,C.-C., Kannagi,R., Rosen,S.D. and Hemmerich,S. (1999) Sulfotransferases of two specificities function in the reconstitution of high endothelial cell ligands for L-selectin. J. Cell Biol., 145, 899910.
Bowman,K.G., Hemmerich,S., Bakhta,S., Singer,M.S., Bistrup,A., Rosen,S.D. and Bertozzi,C.R. (1998) Identification of an N-acetylglucosamine-6-O-sulfotransferase activity specific to lymphoid tissue: an enzyme with a possible role in lymphocyte homing. Chem. Biol., 5, 447460.[ISI][Medline]
Brew,K., Vanaman,T.C. and Hill,R.L. (1968) The role of alpha-lactalbumin and the A protein in lactose synthetase: unique mechanism for the control of a biological reaction. Proc. Natl. Acad. Sci. USA, 59, 491497.[ISI][Medline]
Brodbeck,U., Denton,W.L., Tanahashi,N. and Ebner,K.E. (1967) The isolation and identification of the B protein of lactose synthetase as alpha-lactalbumin. J. Biol. Chem., 242, 13911397.
Capon,C., Wieruszeski,J.-M., Lemoine,J., Byrd,J.C., Leffler,H. and Kim,Y.S. (1997) Sulfated Lewis x determinants as a major structural motif in glycans from LS174T-HM7 human colon carcinoma mucin. J. Biol. Chem., 272, 3195731968.
Carter,S.R., Slomiany,A., Gwozdzinski,K., Liau,Y.H. and Slomiany,B.L. (1988) Enzymatic sulfation of mucus glycoprotein in gastric mucosa. Effect of ethanol. J. Biol. Chem., 263, 1197711984.
Chalifour,R.J. and Spiro,R.G. (1988) Effect of phospholipids on thyroid oligosaccharyltransferase activity and orientation. Evaluation of structural determinants for stimulation of N-glycosylation. J. Biol. Chem., 263, 1567315680.
Chandrasekaran,E.V., Jain,R.K., Vig,R. and Matta,K.L. (1997) The enzymatic sulfation of glycoprotein carbohydrate units: blood group T-hapten specific and two other distinct Gal:3-O-sulfotransferases as evident from specificities and kinetics and the influence of sulfate and fucose residues occurring in the carbohydrate chain on C-3 sulfation of terminal Gal. Glycobiology, 7, 753768.[Abstract]
Degroote,S., Lo-Guidice,J.-M., Strecker,G., Ducourouble,M.-P., Roussel,P. and Lamblin,G. (1997) Characterization of an N-acetylglucosamine-6-O-sulfotransferase from human respiratory mucosa active on mucin carbohydrate chains. J. Biol. Chem., 272, 2949329501.
Dixon,M. and Webb,E.C. (1979) In Enzymes, 3rd ed. London: Longmans, pp. 7275.
Edge,A.S.B. and Spiro,R.G. (1984) Presence of sulfate in N-glycosidically linked carbohydrate units of calf thyroid plasma membrane glycoproteins. J. Biol. Chem., 259, 47104713.
Felipe,M.S. (1969) Value of histochemical reactions for mucosubstances in the diagnosis of certain pathological conditions of the colon and rectum. Gut, 10, 577586.[ISI][Medline]
Fukushima,K., Ohkura,T., Kanai,M., Kuroki,M., Matsuoka,Y., Kobata,A. and Yamashita,K. (1995) Carbohydrate structures of a normal counterpart of the carcinoembryonic antigen produced by colon epithelial cells of normal adults. Glycobiology, 5, 105115.[Abstract]
Goso,Y. and Hotta,K. (1993) Characterization of a rat corpus sulfotransferase for the 6-O-sulfation of ß-D-N-acetylglucosamine residues on oligosaccharides. Glycoconjugate J., 10, 226.
Hemmerich,S., Leffler,H. and Rosen,S.D. (1995) Structure of the O-glycans in GlyCAM-1, an endothelial-derived ligand for L-selectin. J. Biol. Chem., 270, 1203512047.
Hiraoka,N., Petryniak,B., Nakayama,J., Tsuboi,S., Suzuki,M., Yeh,J.-C., Izawa,D., Tanaka,T., Miyasaka,M., Lowe,J.B. and Fukuda,M. (1999) A novel, high endothelial venule-specific sulfotransferase expresses 6-sulfosialyl LewisX, an L-selectin ligand displayed by CD34. Immunity, 11, 7989.[ISI][Medline]
Kannagi,R., Kanamori,A., Mitsuoka,C., Kimura,N. and Ohmori,K. (1999) Significance of sialyl 6-sulfo Lewis x: a new ligand for selectins. Glycoconjugate J., 16, S28S29.
Kobata,A. (1972) Isolation of oligosaccharides from human milk. Methods Enzymol., 28, 262271,.
Kochibe,N. and Matta,K.L. (1989) Purification and properties of an N-acetylglucosamine-specific lectin from Psathyrella velutina mushroom. J. Biol. Chem., 264, 173177.
Kuhns,W., Jain,R.K., Matta,K.L., Paulsen,H., Baker,M.A., Geyer,R. and Brockhausen,I. (1995) Characterization of a novel mucin sulphotransferase activity synthesizing sulphated O-glycan core 1, 3-sulphate-Galß13GalNAc-R. Glycobiology, 5, 689697.[Abstract]
Lee,J.K., Bhakta,S., Rosen,S.D. and Hemmerich,S. (1999) Cloning and characterization of a mammalian N-acetylglucosamine-6-sulfotransferase that is highly restricted to intestinal tissue. Biochem. Biophys. Res. Commun., 263, 543549.[ISI][Medline]
Lo-Guidice,J.-M., Wieruszeski,J.-M., Lemoine,J., Verbert,A., Roussel,P. and Lamblin,G. (1994) Sialylation and sulfation of the carbohydrate chains in respiratory mucins from a patient with cystic fibrosis. J. Biol. Chem., 269, 1879418813.
Loveless,R.W., Yuen,C.-T., Tsuiji,H., Irimura,T. and Feizi,T. (1998) Monoclonal antibody 91.9H raised against sulfated mucins is specific for the 3'-sulfated Lewisa tetrasaccharide sequence. Glycobiology, 8, 12371242.
Matsushita,Y., Yamamoto,N., Shirahama,H., Tanaka,S., Yonezawa,S., Yamori,T., Irimura,T. and Sato,E. (1995) Expression of sulfomucins in normal mucosae, colorectal adenocarcinomas and metastases. Jpn. J. Cancer. Res., 86, 10601067.[ISI][Medline]
Mitranic,M.M., Boggs,J.M. and Moscarello,M.A. (1983) Modulation of bovine milk galactosyltransferase activity by lipids. J. Biol. Chem., 258, 86308636.
Mitsuoka,C., Sawada-Kasugai,M., Ando-Furui,K., Izawa,M., Nakanishi,H., Nakamura,S., Ishida,H., Kiso,M. and Kannagi,R. (1998) Identification of a major carbohydrate capping group of the L-selectin ligand on high endothelial venules in human lymph nodes as 6-sulfo sialyl Lewis X. J. Biol. Chem., 273, 1122511233.
Morson,B.C. and Sobin,L.H. (1990) Histological Typing of Intestinal Tumours, 2nd ed. Berlin: Springer-Verlag.
Sanders,W.J., Katsumoto,T.R., Bertozzi,C.R., Rosen,S.D. and Kiessling,L.L. (1996) L-Selectincarbohydrate interactions, relevant modifications of the Lewis x trisaccharide. Biochemistry, 35, 1486214867.[ISI][Medline]
Seko,A., Ohkura,T., Kitamura,H., Yonezawa,S., Sato,E. and Yamashita,K. (1996) Quantitative differences in GlcNAc:ß13 and GlcNAc:ß1
4 galactosyltransferase activities between human colonic adenocarcinomas and normal colonic mucosa. Cancer Res., 56, 34683473.[Abstract]
Seko,A., Koketsu,M., Nishizono,M., Enoki,Y., Ibrahim,H.R., Juneja,L.R., Kim,M. and Yamamoto,T. (1997) Occurrence of a sialylglycopeptide and free sialylglycans in hens egg yolk. Biochim. Biophys. Acta, 1335, 2332.[ISI][Medline]
Seko,A., Hara-Kuge,S., Yonezawa,S., Nagata,K. and Yamashita,K. (1998) Identification and characterization of N-acetylglucosamine-6-O-sulfate-specific ß1,4-galactosyltransferase in human colorectal mucosa. FEBS Lett., 440, 307310.[ISI][Medline]
Spiro,R.G., Yasumoto,Y. and Bhoyroo,V. (1996) Characterization of a rat liver Golgi sulphotransferase responsible for the 6-O-sulphation of N-acetylglucosamine residues in ß-linkage to mannose: role in assembly of sialyl-galactosyl-N-acetylglucosamine 6-sulphate sequence of N-linked oligosaccharides. Biochem. J., 319, 209216.[ISI][Medline]
Terayama,K., Seiki,T., Nakamura,A., Matsumori,K., Ohta,S., Oka,S., Sugita,M. and Kawasaki,T. (1998) Purification and characterization of a glucuronyltransferase involved in the biosynthesis of the HNK-1 epitope on glycoproteins from rat brain. J. Biol. Chem., 273, 3029530300.
Uchimura,K., Muramatsu,H., Kadomatsu,K., Fan,Q.-W., Kurosawa,N., Mitsuoka,C., Kannagi,R., Habuchi,O. and Muramatsu,T. (1998a) Molecular cloning and characterization of an N-acetylglucosamine-6-O-sulfotransferase. J. Biol. Chem., 273, 2257722583.
Uchimura,K., Muramatsu,H., Kaname,T., Ogawa,H., Yamakawa,T., Fan,Q.-W., Mitsuoka,C., Kannagi,R., Habuchi,O., Yokoyama,I. and others. (1998b) Human N-acetylglucosamine-6-O-sulfotransferase involved in the biosynthesis of 6-sulfo sialyl Lewis X: molecular cloning, chromosomal mapping and expression in various organs and tumor cells. J. Biochem., 124, 670678.[Abstract]
Westcott,K.R., Wolf,C.C. and Hill,R.L. (1985) Regulation of ß-D-galactoside 2
3 sialyltransferase activity. The effects of detergents and lysophosphatidates. J. Biol. Chem., 260, 1310913115.
Yamashita,K., Totani,K., Kuroki,M., Matsuoka,Y., Ueda,I. and Kobata,A. (1987) Structural studies of the carbohydrate moieties of carcinoembryonic antigens. Cancer Res., 47, 34513459.[Abstract]
Yamashita,K., Totani,K., Iwaki,Y., Kuroki,M., Matsuoka,Y., Endo,T. and Kobata,A. (1989) Carbohydrate structures of NCA-2, a glycoprotein purified from meconium as an antigen cross-reacting with anti-CEA antibody: occurrence of complex-type sugar chains with the Galß1 3GlcNAcß1
3Galß1
4GlcNAcß1
outer chains. J. Biol. Chem., 264, 1787317881.
Yamashita,K. and Kobata,A. (1996) Cancer cells and metastasis. Carcinoembryonic antigen and related normal antigens. In Montreuil,J., Vliegenthart,J.F.G., and Schachter,H. (eds.), Glycoproteins and Disease. Elsevier, Amsterdam, pp. 229239.
Yamori,T., Kimura,H., Stewart,K., Ota,D.M., Cleary,K.R. and Irimura,T. (1987) Differential production of high molecular weight sulfated glycoproteins in normal colonic mucosa, primary colon carcinoma and metastases. Cancer Res., 47, 27412747.[Abstract]
Yang,J.-M., Byrd,J.C., Siddiki,B.B., Chung,Y.-S., Okuno,M., Sowa,M., Kim,Y.S., Matta,K.L. and Brockhausen,I. (1994) Alterations of O-glycan biosynthesis in human colon cancer tissues. Glycobiology, 4, 873884.[Abstract]
Zakim,D., Cantor,M. and Eibl,H. (1988) Phospholipids and UDP-glucuronosyltransferase. Structure/function relationships. J. Biol. Chem., 263, 51645169.