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Dall'Olio F, Malagolini N, Trinchera M, Chiricolo M. Sialosignaling: Sialyltransferases as engines of self-fueling loops in cancer progression. Biochim Biophys Acta Gen Subj 2014; 1840:2752-64. [DOI: 10.1016/j.bbagen.2014.06.006] [Citation(s) in RCA: 99] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2014] [Revised: 05/13/2014] [Accepted: 06/10/2014] [Indexed: 02/03/2023]
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2
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Affiliation(s)
- F Dall'olio
- Dipartimento di Patologia Sperimentale, Università di Bologna, Via S. Giacomo, 14, 40126 Bologna, Italy
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3
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Malagolini N, Chiricolo M, Marini M, Dall'Olio F. Exposure of 2,6-sialylated lactosaminic chains marks apoptotic and necrotic death in different cell types. Glycobiology 2008; 19:172-81. [DOI: 10.1093/glycob/cwn122] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Takahashi T, Naka T, Fujimoto M, Serada S, Horino J, Terabe F, Hirota S, Miyoshi. E, Hirai T, Nakajima K, Nishitani A, Souma Y, Sawa Y, Nishida T. Aberrant expression of glycosylation in juvenile gastrointestinal stromal tumors. Proteomics Clin Appl 2008; 2:1246-54. [DOI: 10.1002/prca.200700119] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2007] [Indexed: 12/15/2022]
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Shaikh FM, Seales EC, Clem WC, Hennessy KM, Zhuo Y, Bellis SL. Tumor cell migration and invasion are regulated by expression of variant integrin glycoforms. Exp Cell Res 2008; 314:2941-50. [PMID: 18703050 DOI: 10.1016/j.yexcr.2008.07.021] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2008] [Revised: 07/15/2008] [Accepted: 07/16/2008] [Indexed: 12/15/2022]
Abstract
The ST6Gal-I glycosyltransferase, which adds alpha2-6-linked sialic acids to glycoproteins, is overexpressed in colon adenocarcinoma, and enzyme activity is correlated with tumor cell invasiveness. Previously we reported that forced expression of oncogenic ras in HD3 colonocytes causes upregulation of ST6Gal-I, leading to increased alpha2-6 sialylation of beta1 integrins. To determine whether ras-induced sialylation is involved in promoting the tumor cell phenotype, we used shRNA to downregulate ST6Gal-I in ras-expressors, and then monitored integrin-dependent responses. Here we show that forced ST6Gal-I downregulation, leading to diminished alpha2-6 sialylation of integrins, inhibits cell adhesion to collagen I, a beta1 ligand. Correspondingly, collagen binding is reduced by enzymatic removal of cell surface sialic acids from ras-expressors with high ST6Gal-I levels (i.e., no shRNA). Cells with forced ST6Gal-I downregulation also exhibit decreased migration on collagen I and diminished invasion through Matrigel. Importantly, GD25 cells, which lack beta1 integrins (and ST6Gal-I), do not demonstrate differential invasiveness when forced to express ST6Gal-I, suggesting that the effects of variant sialylation are mediated specifically by beta1 integrins. The observation that cell migration and invasion can be blocked in oncogenic ras-expressing cells by forcing ST6Gal-I downregulation implicates differential sialylation as an important ras effector, and also suggests that ST6Gal-I is a promising therapeutic target.
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Affiliation(s)
- Faheem M Shaikh
- Department of Physiology and Biophysics, University of Alabama at Birmingham, Birmingham, Alabama 35294, USA
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7
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Naeem A, Haque S, Khan RH. Purification and Characterization of a Novel β-d-Galactosides-Specific Lectin from Clitoria ternatea. Protein J 2007; 26:403-13. [PMID: 17514413 DOI: 10.1007/s10930-007-9080-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A lectin present in seeds of Clitoria ternatea agglutinated trypsin-treated human B erythrocytes. The sugar specificity assay indicated that lectin belongs to Gal/Gal NAc-specific group. Hence the lectin, designated C. ternatea agglutinin (CTA), was purified by the combination of acetic acid precipitation, salt fractionation and affinity chromatography. HPLC gel filtration, SDS-polyacrylamide gel electrophoresis and mass spectrometry indicated that the native lectin is composed of two identical subunits of molecular weight 34.7 kDa associated by non covalent bonds. The N-terminal sequence of CTA shared homology with Glycine max and Pisum sativum. Complete sequence was also found to be homologous to S-64 protein of Glycine max, suggesting that CTA probably exhibits both hemagglutination and probably sugar uptake activity. The carbohydrate binding specificity of the lectin was investigated by quantitative turbidity measurements, and percent inhibition assays. Based on these assays, we conclude that CTA binds beta-D: -galactosides, and also may has an extended specificity towards non-reducing terminal Neu5Acalpha2,6Gal.
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Affiliation(s)
- Aabgeena Naeem
- Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh, 202 002, India
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8
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Poon TCW, Chiu CHS, Lai PBS, Mok TSK, Zee B, Chan ATC, Sung JJY, Johnson PJ. Correlation and prognostic significance of beta-galactoside alpha-2,6-sialyltransferase and serum monosialylated alpha-fetoprotein in hepatocellular carcinoma. World J Gastroenterol 2005; 11:6701-6. [PMID: 16425369 PMCID: PMC4355769 DOI: 10.3748/wjg.v11.i42.6701] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To investigate the correlation between tissue ST6Gal I and serum msAFP in HCC patients, and to investigate their prognostic significance.
METHODS: Preoperative sera, paired tumorous and non-tumorous tissues were collected from 19 consecutive patients who had undergone surgical resection of HCC. ST6Gal I activities in the tissues were measured by an in vitro microsomal enzyme activity assay. The percentages of tumor-specific msAFP in the sera were also estimated by an isoelectric focusing-immunoblotting assay.
RESULTS: The tumor ST6Gal I activity was negatively correlated with serum msAFP percentage (r = -0.53, P = 0.019). Both decreased tumor ST6Gal I activity and increased serum msAFP percentage were associated with poor tumor cell differentiation. Univariate analyses showed that both decreased tumor ST6Gal I activity (P = 0.028), increased serum msAFP percentage (P = 0.034) and poor tumor cell differentiation (P = 0.031) were associated with shorter overall survival. Multivariate analysis using the Cox regression model showed that the preoperative serum msAFP percentage (P = 0.022) and tumor cell differentiation status (P = 0.048) were independent prognostic indicators for patient overall survival.
CONCLUSION: Our results indicate that the presence of msAFP in blood circulation is associated with a decreased activity of ST6Gal I activity in HCC. Both tissue ST6Gal I and serum msAFP are potential prognostic markers for patients with operable HCC.
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Affiliation(s)
- Terence C W Poon
- Department of Medicine and Therapeutics, Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong, China.
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9
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Whalen LJ, McEvoy KA, Halcomb RL. Synthesis and evaluation of phosphoramidate amino acid-based inhibitors of sialyltransferases. Bioorg Med Chem Lett 2003; 13:301-4. [PMID: 12482445 DOI: 10.1016/s0960-894x(02)00735-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Several phosphoramidate analogues of CMP-N-acetylneuraminic acid were prepared for evaluation as inhibitors of alpha-2,3- and alpha-2,6-sialyltransferase. Central to the synthesis was the oxidative coupling of an amino acid ester with an H-phosphonate to construct the phosphoramidate linkage. All compounds synthesized were weak inhibitors of both of the sialyltransferases as determined by an HPLC-based inhibition assay.
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Affiliation(s)
- Lisa J Whalen
- University of Colorado, Department of Chemistry and Biochemistry, UCB 215, Boulder, CO 80309-0215, USA
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10
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Abstract
It has long been known that cancer cells often express more heavily sialylated glycans on their surface and that this feature sometimes correlates with invasion. It is now well established that specific sialylated structures, such as the Thomsen-Friedenreich-related antigens, the sialyl Lewis antigens, the sialyl alpha2-6 lactosaminyl structure, the polysialic acid or some gangliosides, can mediate cellular interactions and are altered in cancer cells. This review summarizes the current knowledge on the cancer-associated alterations in sialyltransferase expression which are often at the basis of the deranged expression of sialylated structures.
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Affiliation(s)
- F Dall'Olio
- Dipartimento di Patologia Sperimentale, Università di Bologna, Via S. Giacomo 14, 40126 Bologna, Italy
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11
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Dall'Olio F, Chiricolo M, Mariani E, Facchini A. Biosynthesis of the cancer-related sialyl-alpha 2,6-lactosaminyl epitope in colon cancer cell lines expressing beta-galactoside alpha 2,6-sialyltransferase under a constitutive promoter. EUROPEAN JOURNAL OF BIOCHEMISTRY 2001; 268:5876-84. [PMID: 11722575 DOI: 10.1046/j.0014-2956.2001.02536.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
An elevation of beta-galactoside alpha 2,6-sialyltransferase (ST6Gal.I) enzyme activity and an increased alpha 2,6-sialylation of cell membranes are among the most prominent glycosylation changes associated with colon cancer; both modifications correlate with a worse prognosis. In our previous studies, we have frequently observed a discrepancy between the ST6Gal.I level within a colon cancer sample or cell line and the respective level of reactivity with the alpha 2,6-sialyl-specific lectin from Sambucus nigra (SNA). In this study, we have investigated quantitatively the biosynthesis of the sialyl-alpha 2,6-lactosaminyl epitope in two colon cancer cell types expressing the ST6Gal.I cDNA under the control of a constitutive promoter. By measuring the amount of ST6Gal.I mRNA using competitive RT-PCR, the expression of alpha 2,6-sialylated lactosaminic structures with SNA and anti-CDw75 Ig, and the presence of unsubstituted lactosaminic termini by Erythrina cristagalli lectin, we reached the following conclusions: (a) a high proportion of the cell surface lactosaminic termini remains unsubstituted, even in the presence of a very high ST6Gal.I activity. This proportion is strongly dependent on the cell type; (b) ST6Gal.I-transfected colon cancer cells do not express the CDw75 epitope; (c) the level of ST6Gal.I enzyme activity only partially correlates with the mRNA level; (d) despite the control by a constitutive promoter, the ST6Gal.I mRNA is not constantly expressed over time; and (e) a very large portion of the enzyme molecules is secreted in the extracellular milieu. These results indicate that post-transcriptional and post-translational mechanisms play a pivotal role in the control of alpha 2,6-sialylation in colon cancer cells.
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Affiliation(s)
- F Dall'Olio
- Dipartimento di Patologia Sperimentale, Università di Bologna, Italy.
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Accili D, Menghi M, Materazzi G, Menghi G. Sialic acid derivatives and their distribution in rat sublingual gland acini during pre- and post-natal development. THE HISTOCHEMICAL JOURNAL 2001; 33:363-71. [PMID: 11758813 DOI: 10.1023/a:1012487426639] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Sialoglycoconjugates in rat sublingual gland acinar cells, at different stages of pre- and post-natal development, were investigated in situ with specific lectins and by the selective removal of terminal sialic acids. Cleavage of acetyl substituents sited in the pyranose ring and/or polyhydroxyl side chain was used as an additional means of characterising the glycoconjugates. The first expression of terminal sialic acid linked to beta-galactose was found at gestational day 17 and progressive different derivatives were observed. The terminal disaccharide sialic acid-N-acetylgalactosamine was constantly visualized in the sublingual gland from gestational day 18. In both terminal disaccharides, sialic acids were characterized by variable degrees of acetylation and were found to be highly packaged and responsible for the hydration coat. The complex data obtained indicated that the sublingual gland is characterized by a marked fluctuation of complex sialoglycoconjugates that differ from those in the submandibular gland of the same species.
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Affiliation(s)
- D Accili
- Department of Comparative Morphology and Biochemistry, University of Camerino, (MC), Italy
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13
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Abstract
Sialylation represents one of the most frequently occurring terminations of the oligosaccharide chains of glycoproteins and glycolipids. Sialic acid is commonly found alpha2,3- or alpha2,6-linked to galactose (Gal), alpha2,6-linked to N-acetylgalactosamine (GalNAc) or alpha2,8-linked to another sialic acid. The biosynthesis of the various linkages is mediated by the different members of the sialyltransferase family. The addition of sialic acid in alpha2,6-linkage to the galactose residue of lactosamine (type 2 chains) is catalyzed by beta-galactoside alpha2,6-sialyltransferase (ST6Gal.I). Although expressed by a single gene, this enzyme shows a complex pattern of regulation which allows its tissue- and stage-specific modulation. The cognate oligosaccharide structure, NeuAcalpha2,6Galbeta1,4GlcNAc, is widely distributed among tissues and is involved in biological processes such as the regulation of the immune response and the progression of colon cancer. This review summarizes the current knowledge on the biochemistry of ST6Gal.I and on the functional role of the sialyl-alpha2,6-lactosaminyl structure.
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Affiliation(s)
- F Dall'Olio
- Dipartimento di Patologia Sperimentale, Università di Bologna, Italy
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Dall'Olio F, Chiricolo M, Ceccarelli C, Minni F, Marrano D, Santini D. Beta-galactoside alpha2,6 sialyltransferase in human colon cancer: contribution of multiple transcripts to regulation of enzyme activity and reactivity with Sambucus nigra agglutinin. Int J Cancer 2000; 88:58-65. [PMID: 10962440 DOI: 10.1002/1097-0215(20001001)88:1<58::aid-ijc9>3.0.co;2-q] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Colon cancer tissues display an increased activity of beta-galactoside alpha2,6 sialyltransferase (ST6Gal.I) and an increased reactivity with the lectin from Sambucus nigra (SNA), specific for alpha2,6-sialyl-linkages. Experimental and clinical studies indicate a contribution of these alterations to tumor progression, but their molecular bases are largely unknown. In many tissues, ST6Gal.I is transcriptionally regulated through the usage of different promoters that originate mRNAs diverging in the 5;-untranslated regions. RT-PCR analysis of 14 carcinoma samples, all expressing an increased ST6Gal.I enzyme activity, and of the corresponding normal mucosa revealed the presence of at least 2 transcripts. One, containing the 5;-untranslated exons, Y+Z, is thought to represent the "housekeeping" expression, and another previously described in hepatic tissues. Both the Y+Z and the hepatic transcripts were detectable in normal and cancer tissues but that latter form had a marked tendency to accumulate in cancer. The extent of alpha2,6-sialylation of glycoconjugates, as determined by SNA-dot blot analysis, was markedly enhanced in all cancer specimens, but the level of reactivity only partially correlated with the level of enzyme expression. Western blot analysis revealed a strikingly heterogeneous pattern of SNA reactivity among cancer tissues. These data indicate that: i) during neoplastic transformation of colonic cells, ST6Gal.I expression may be modulated through a differential promoter usage; ii) the extent of alpha2,6-sialylation of cancer cell membranes is not a direct function of the ST6Gal.I activity, strongly suggesting the existence of other, more complex mechanisms of regulation.
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Affiliation(s)
- F Dall'Olio
- Dipartimento di Patologia Sperimentale, Università di Bologna, Bologna, Italy.
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Slimane TA, Lenoir C, Sapin C, Maurice M, Trugnan G. Apical secretion and sialylation of soluble dipeptidyl peptidase IV are two related events. Exp Cell Res 2000; 258:184-94. [PMID: 10912800 DOI: 10.1006/excr.2000.4894] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The role of glycans in the apical targeting of proteins in epithelial cells remains a debated question. We have expressed the mouse soluble dipeptidyl peptidase IV (DPP IV ectodomain) in kidney (MDCK) and in intestinal (Caco-2) epithelial cell lines, as a model to study the role of glycosylation in apical targeting. The mouse DPP IV ectodomain was secreted mainly into the apical medium by MDCK cells. Exposure of MDCK cells to GalNac-alpha-O-benzyl, a drug previously described as an inhibitor of mucin O-glycosylation, produced a protein with a lower molecular weight. In addition this treatment resulted in a decreased apical secretion and an increased basolateral secretion of mouse DPP IV ectodomain. When expressed in Caco-2 cells, the mouse DPP IV ectodomain was secreted mainly into the basolateral medium. However, BGN was still able to decrease the amount of apically secreted protein and to increase its basolateral secretion. Neuraminidase digestion showed that the most striking effect of BGN was a blockade of DPP IV sialylation in both MDCK and Caco-2 cells. These results indicate that a specific glycosylation step, namely, sialylation, plays a key role in the control of the apical targeting of a secreted DPP IV both in MDCK and Caco-2 cells.
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Affiliation(s)
- T A Slimane
- INSERM U 538, CHU St. Antoine, Paris, France
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Mo H, Winter HC, Goldstein IJ. Purification and characterization of a Neu5Acalpha2-6Galbeta1-4Glc/GlcNAc-specific lectin from the fruiting body of the polypore mushroom Polyporus squamosus. J Biol Chem 2000; 275:10623-9. [PMID: 10744758 DOI: 10.1074/jbc.275.14.10623] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
A lectin has been purified from the carpophores of the mushroom Polyporus squamosus by a combination of affinity chromatography on beta-D-galactosyl-Synsorb and ion-exchange chromatography on DEAE-Sephacel. Gel filtration chromatography, SDS-polyacrylamide gel electrophoresis, and N-terminal amino acid sequencing indicated that the native lectin, designated P. squamosus agglutinin, is composed of two identical 28-kDa subunits associated by noncovalent bonds. P. squamosus agglutinin agglutinated human A, B, and O and rabbit red blood cells but precipitated only with human alpha(2)-macroglobulin, of many glycoproteins and polysaccharides tested. The detailed carbohydrate binding properties of the purified lectin were elucidated using three different approaches, i.e. precipitation inhibition assay (in solution binding assay), fluorescence quenching studies, and glycolipid binding by lectin staining on high-performance thin layer chromatography (solid-phase binding assay). Based on the results obtained by these assays, we conclude that although the P. squamosus lectin binds beta-D-galactosides, it has an extended carbohydrate-combining site that exhibits highest specificity and affinity toward nonreducing terminal Neu5Acalpha2, 6Galbeta1,4Glc/GlcNAc (6'-sialylated type II chain) of N-glycans (2000-fold stronger than toward galactose). The strict specificity of the lectin for alpha2,6-linked sialic acid renders this lectin a valuable tool for glycobiological studies in biomedical and cancer research.
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Affiliation(s)
- H Mo
- Department of Biological Chemistry, The University of Michigan Medical School, Ann Arbor, Michigan 48109-0606, USA
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Petretti T, Schulze B, Schlag PM, Kemmner W. Altered mRNA expression of glycosyltransferases in human gastric carcinomas. BIOCHIMICA ET BIOPHYSICA ACTA 1999; 1428:209-18. [PMID: 10434038 DOI: 10.1016/s0304-4165(99)00080-x] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Biosynthesis of carbohydrate structures is tissue-specific and developmentally regulated by glycosyltransferases like fucosyl-, sialyl- and N-acetylglucosaminyltransferases. During carcinogenesis, aberrant glycosylation leads to the development of tumor subpopulations with different adhesion properties. The aim of this contribution was to directly compare mRNA expression of several glycosyltransferases in surgical specimens of gastric carcinomas. Carcinoma specimens were classified and characterized according to the WHO/UICC system. In each case, the expression of 12 glycosyltransferase enzymes was studied simultaneously by RT-PCR. For semi-quantitative analysis, amplification of the sample sequence was compared with that of beta-actin, co-amplified within the same tube. Expression of N-acetylglucosaminyltransferase V in gastric carcinomas was significantly enhanced compared to normal tissue. Also, expression of sialyltransferase ST3Gal-IV and fucosyltransferase FT-IV was significantly enhanced in carcinoma tissue. No significant differences in glycosyltransferase expression were found in samples positive for Helicobacter pylori or between the different gastric regions. Thus, carcinogenesis is characterized by specific alterations in mRNA expression of several glycosyltransferases. Future studies will show whether RT-PCR detection of the expression of these enzymes could be helpful for prognostic purposes.
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Affiliation(s)
- T Petretti
- Department of Surgery and Surgical Oncology, Klinikum Charite, Robert-Rössle-Klinik at the Max-Delbrück-Center of Molecular Medicine, Lindenberger Weg 80, D-13125, Berlin, Germany
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Dall'Olio F, Chiricolo M, Lau JT. Differential expression of the hepatic transcript of beta-galactoside alpha2,6-sialyltransferase in human colon cancer cell lines. Int J Cancer 1999; 81:243-7. [PMID: 10188726 DOI: 10.1002/(sici)1097-0215(19990412)81:2<243::aid-ijc13>3.0.co;2-o] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The activity of beta-galactoside alpha2,6-sialyltransferase (ST6Gal.1), the enzyme responsible for the addition of sialic acid in alpha2,6-linkage to N-acetyllactosaminic (Gal beta1,4GlcNAc) units of glycoconjugates, is increased in the vast majority of colon cancer specimens, and a positive correlation with an invasive phenotype has been suggested by several studies. In many tissues, ST6Gal.1 is regulated mainly at the transcriptional level through the use of different cell-specific promoters which generate transcripts differing in their 5'-untranslated regions. With the aim of understanding the molecular bases of the increased ST6Gal.1 expression in colon cancer, we investigated the expression of mRNA species in colon cancer cell lines and the relationship with enzyme activity and extent of alpha2,6-sialylation of cell glycoproteins. All cell lines examined express the form containing the 5'-untranslated exons Y and Z, typical of the "basal" expression of the gene, while others express also the liver transcript. This indicates that colon cancer cell lines can be grouped according to expression of the liver transcript of ST6Gal.1. The cell lines expressing only the Y+Z form display, in general, a lower activity:mRNA ratio, which might indicate reduced translational efficiency. The level of alpha2,6-sialylation of cell glycoproteins, as determined by reactivity with the Sambucus nigra lectin, is closely associated with the level of enzyme activity.
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Affiliation(s)
- F Dall'Olio
- Department of Experimental Pathology, University of Bologna, Italy.
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Dimitroff CJ, Pera P, Dall'Olio F, Matta KL, Chandrasekaran EV, Lau JT, Bernacki RJ. Cell surface n-acetylneuraminic acid alpha2,3-galactoside-dependent intercellular adhesion of human colon cancer cells. Biochem Biophys Res Commun 1999; 256:631-6. [PMID: 10080950 DOI: 10.1006/bbrc.1999.0388] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Sialoglycans on the cell surface of human colon cancer (HCC) cells have been implicated in cellular adhesion and metastasis. To clarify the role of N-acetylneuraminic acid (NeuAc) linked alpha2,3 to galactose (Gal) on the surface of HCC cells, we studied the intercellular adhesion of HCC cell lines expressing increasing NeuAcalpha2,3Gal-R. Our model system consisted of the HCC SW48 cell line, which inherently possesses low levels of cell surface alpha2,3 and alpha2,6 sialoglycans. To generate SW48 clonal variants with elevated cell surface NeuAcalpha2,3Gal-R linkages, we transfected the expression vector, pcDNA3, containing either rat liver cDNA encoding Galbeta1,3(4)GlcNAc alpha2,3 sialyltransferase (ST3Gal III) or human placental cDNA encoding Galbeta1,3GalNAc/Galbeta1,4GlcNAc alpha2,3 sialyltransferase (ST3Gal IV) into SW48 cells. Selection of neomycin-resistant clones (600 microgram G418/ml) having a higher percentage of cells expressing NeuAcalpha2,3Gal-R (up to 85% positive Maackia amurenis agglutinin staining compared with 30% for wild type cells) was performed. These ST3Gal III and ST3Gal IV clonal variants demonstrated increased adherence to IL-1beta-activated human umbilical vein endothelial cells (HUVEC) (up to 90% adherent cells compared with 63% for wild type cells). Interestingly, ST3Gal III and ST3Gal IV clonal variants also bound non-activated HUVEC up to 4-fold more effectively than wild type cells. Cell surface NeuAcalpha2,3Gal-R expression within the various SW48 clonal variants correlated directly with increased adhesion to HUVEC (r=0.84). Using HCC HT-29 cells, which express high levels of surface NeuAcalpha2,3Gal-R, addition of synthetic sialyl, sulfo or GalNAc Lewis X structures were found to specifically inhibit intercellular adhesion. At 1.0mM, NeuAcalpha2,3Galbeta1,3(Fucalpha1, 4)GlcNAc-OH and Galbeta1,4(Fucalpha1,3)GlcNAcbeta1,6(SE-6Galbeta1++ +, 3)GalNAcalpha1-O-methyl inhibited HT-29 cell adhesion to IL-1beta-stimulated HUVEC by 100% and 68%, respectively. GalNAcbeta1, 4(Fucalpha1,3)GlcNAcbeta1-O-methyl and GalNAcbeta1,4(Fucalpha1, 3)GlcNAcbeta1,6Manalpha1,6Manbeta1-0-C30H61, however, did not possess inhibitory activity. In conclusion, these studies demonstrated that cell surface NeuAcalpha2,3Gal-R expression is involved in HCC cellular adhesion to HUVEC. These specific carbohydrate-mediated intercellular adhesive events may play an important role in tumor angiogenesis, metastasis and growth control.
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Affiliation(s)
- C J Dimitroff
- Department of Pharmacology and Therapeutics, Department of Gynecologic Oncology, Roswell Park Cancer Institute, Elm and Carlton Streets, Buffalo, New York, 14263, USA
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Müller B, Schaub C, Schmidt RR. Effiziente Sialyltransferase-Inhibitoren auf der Basis von Übergangszustandsanaloga des Sialyldonors. Angew Chem Int Ed Engl 1998. [DOI: 10.1002/(sici)1521-3757(19981016)110:20<3021::aid-ange3021>3.0.co;2-i] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Palmetshofer A, Robson SC, Bach FH. Tyrosine phosphorylation following lectin mediated endothelial cell stimulation. Xenotransplantation 1998; 5:61-6. [PMID: 9507735 DOI: 10.1111/j.1399-3089.1998.tb00010.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Terminal alpha (1,3) galactosyl galactoside epitopes (alpha-gal) on membrane glycoproteins expressed by vascular endothelial cells represent the major xenoreactive antigens in pig to primate xenotransplantation. In other discordant xenotransplantation combinations, such as from guinea pig to rat, carbohydrate epitopes other than alpha-gal may be targeted by xenoreactive antibodies (XNA). We have shown that agonist binding to alpha-gal epitopes induces proinflammatory activation of porcine aortic endothelial cells (PAEC). Binding of alpha-gal epitopes by Bandeiraea simplicifolia isolectin B4 results in both type I and type II PAEC activation. This includes the phosphorylation of tyrosine residue(s) of a protein with an apparent molecular weight of 130 kDa (p130). In order to investigate whether binding of other carbohydrate epitopes could induce a similar phosphorylation event, several lectins with different carbohydrate specificities were used to stimulate PAEC and human umbilical endothelial cells (HUVEC). In addition to BS-IB4 binding to alpha-gal, lectins binding to sialic acid isolated from Sambucus nigra (SNA), Maackia amurensis (MAA), Wheat germ agglutinin (WGA), and lectin from jack bean (Concanavalin A, ConA), that binds to mannose residues within the core structure of N-glycosylated proteins all induced the phosphorylation of the p130 protein(s). Lectins with affinity to alpha bound N-acetylgalactosamine, Dolichos biflorus (DOB), and Sophora japonoca (SOJ) did not induce this phosphorylation event. A similar negative result was obtained with Ulex europaeus lectin I, which binds to fucose residues. Conclusively, endothelial cell activation can be observed upon binding of various lectins to the glycosylated moiety of surface glycoproteins. These carbohydrate epitopes against which XNA may exist in certain models might represent minor xenoantigens from porcine to primates or may comprise the major xenoepitopes in other discordant xenograft models. Binding of XNA and subsequently the elicited xenoreactive antibodies to carbohydrate epitopes may therefore contribute to xenograft rejection even in the absence of complement inactivation.
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Affiliation(s)
- A Palmetshofer
- Novartis Center for Immunobiology, Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA.
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22
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Kemmner W, Hohaus K, Schlag PM. Inhibition of Gal beta1, 4GlcNAc alpha2,6 sialyltransferase expression by antisense-oligodeoxynucleotides. FEBS Lett 1997; 409:347-50. [PMID: 9224687 DOI: 10.1016/s0014-5793(97)00543-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Treatment of human colorectal carcinoma cells HT29 with specific antisense oligodeoxynucleotides led to a decreased Gal beta1,4GlcNAc alpha2,6 sialyltransferase activity on the level of protein expression as well as on the mRNA level. Antisense treatment did not effect cell viability or cell growth. Oligodeoxynucleotides which were complementary to the region upstream of the initiation codon were particularly effective in inhibition of enzyme expression. No such inhibition was found by treatment of cells with oligodeoxynucleotides complementary to the region downstream of the initiation codon or by treatment of cells with scrambled controls or sense oligodeoxynucleotides.
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Affiliation(s)
- W Kemmner
- Department of Surgical Oncology, Robert-Rössle-Klinik at the Max-Delbrück-Centrum for Molecular Medicine, Berlin, Germany.
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23
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Murayama T, Zuber C, Seelentag WK, Li WP, Kemmner W, Heitz PU, Roth J. Colon carcinoma glycoproteins carrying alpha 2,6-linked sialic acid reactive with Sambucus nigra agglutinin are not constitutively expressed in normal human colon mucosa and are distinct from sialyl-Tn antigen. Int J Cancer 1997; 70:575-81. [PMID: 9052758 DOI: 10.1002/(sici)1097-0215(19970304)70:5<575::aid-ijc14>3.0.co;2-c] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
In human colon carcinoma, increased amounts of sialic acids have been found and correlated with tumor progression. Further, the degree of O-acetylation of sialic acid residues in normal mucosa is higher than in colon carcinoma. Thus, tumor-associated sialylated antigens may be constitutively expressed in O-acetylated form in normal mucosa unreactive with the respective monoclonal antibodies. We have earlier demonstrated a colon carcinoma-associated expression of alpha 2,6-linked sialic acid residues with the Sambucus nigra agglutinin (SNA). We report now that de-acetylation of normal and transitional colonic mucosa, in contrast to sialyl-Tn antigen, does not result in SNA binding. Further, the alpha 2,6-linked sialic acid recognized by SNA is distinct from that of sialyl-Tn antigen. This is confirmed by Northern blotting detecting transcripts for alpha 2,6 sialyltransferase of N-glycoproteins and measurement of activity for this sialyltransferase. Blot analysis by SNA of colon carcinoma cells revealed few reactive glycoproteins. Quantitative differences in lectin labeling and sialyltransferase activity were found in HCT116 colon carcinoma cell sub-lines. Our data suggest that SNA binding in human colon carcinoma is due to de novo expression of a specific sialic acid present on selected glycoproteins.
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Affiliation(s)
- T Murayama
- Department of Pathology, University of Zurich, Switzerland
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24
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Nagpurkar A, Hunt D, Mookerjea S. Specific stimulation of alpha 2-6 sialyltransferase activity by a novel cytosolic factor from rat colon. Int J Biochem Cell Biol 1996; 28:1337-48. [PMID: 9022292 DOI: 10.1016/s1357-2725(96)00092-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
A factor present in the 100,000 g supernatant from the homogenate of rat colon stimulated the activity of purified Gal beta 1-4GLcNAc alpha 2,6 sialyltransferase [alpha 2-6ST(N)] from rat liver and alpha 2-6ST(N) from either liver microsomes or Golgi membrane. The stimulation of alpha 2-6ST(N) activity by the colon factor using protein acceptors was about four-fold and highly reproducible when the reaction product of the alpha 2-6ST(N) was assayed by either precipitation or affinity chromatography. In contrast, the colon factor did not stimulate the Gal beta 1-4GlcNAc alpha 2,3 sialyltransferase [alpha 2-3ST (N)], from rat jejunum microsomes or purified Gal beta 1-3GalNAc alpha 2,4 sialyltransferase [alpha 2-3ST (O)] from porcine liver, of purified beta 1,4 galactosyltransferase (GT) from bovine milk. In addition to rat colon, the 100,00 g supernatant from the homogenates of rat brain and kidney also stimulated the alpha 2-6ST(N) activity. The stimulation of alpha 2-6ST(N) by the colon factor resulted in a decrease in the Km (by about two-fold) and an increase in Vmax (about 2- to 3-fold) for desialylated alpha 1 acid glycoprotein and CMP-[14C]N-acetylneuraminic acid. The stimulation of alpha 2-6ST(N) activity by the colon factor was temperature dependent, protease sensitive and was inhibited by CTP, but did not need the presence of either metal ions or detergent. The cytosolic factor was partially purified by ion-exchange chromatography with the retention of the activator activity in the peaks containing low molecular weight proteins, but the activity was lost on attempts to further purification. A specific marked stimulation of the alpha 2-6ST(N) activity by cytosolic factors in certain tissues might suggest a physiological role for these factors in the regulation of alpha 2-5ST(N) activity.
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Affiliation(s)
- A Nagpurkar
- Department of Biochemistry, Memorial University, St. John's, Newfoundland, Canada
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25
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Dall'Olio F, Malagolini N, Guerrini S, Lau JT, Serafini-Cessi F. Differentiation -dependent expression of human beta-galactoside alpha 2,6-sialyltransferase mRNA in colon carcinoma CaCo-2 cells. Glycoconj J 1996; 13:115-21. [PMID: 8785482 DOI: 10.1007/bf01049687] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
We have previously documented a dramatic elevation in the activity of alpha 2,6-sialytransferase towards Gal beta 1,4GlcNAc (EC 2.4.99.1) (alpha 2,6ST) in CaCo-2 cells maintained in culture for several days after confluence to elicit a high degree of enterocytic differentiation phenotype. Northern analysis performed with a probe complementary to a region of human alpha 2,6ST mRNA common to all known transcripts demonstrated that the expression of alpha 2,6ST mRNA in CaCo-2 cells increased with the degree with the degree of differentiation. When probes complementary to 5'-untranslated exons (Y + Z or X) previously identified in transcripts isolated from human placenta and from several human lymphoblastoid cell lines were used, no hybridization signal with mRNA of CaCo-2 cells was found, as reported for the mRNA of hepatoma cell line HepG2 (Wang XC, Vertino A, Eddy RL, Byers MG, Jani-Sait SN, Shows TB, Lau JTY (1993) J Biol Chem 268: 4355-61). These results support the notion that the major alpha 2,6ST transcript of CaCo-2 cells was the hepatoma isoform or a new one, so far unreported. Consistent with the differentiation-dependent increase in alpha 2,6ST-mRNA expression, an elevation of the reactivity with Sambucus nigra agglutinin of differentiated CaCo-2 cell-surface was observed, indicating an enhanced alpha 2,6-sialylation of membrane glycoconjugates.
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Affiliation(s)
- F Dall'Olio
- Department of Experimental Pathology, University of Bologna, Italy
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26
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Kemmner W, Krück D, Schlag P. Different sialyltransferase activities in human colorectal carcinoma cells from surgical specimens detected by specific glycoprotein and glycolipid acceptors. Clin Exp Metastasis 1994; 12:245-54. [PMID: 8194200 DOI: 10.1007/bf01753893] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The amount and type of sialylation of tumor cell membranes depends on the activity of a number of different sialyltransferase enzymes. For the detection of specific activities in human colorectal carcinoma tissue several glycoprotein and glycolipid acceptors were used: desialylated fetuin, alpha 1-acid glycoprotein, beta 2-glycoprotein I, ovine submaxillaris mucin, and the gangliosides GM1, GM2, GM3 and GD1a. Because of their possible relevance for metastasis, precursors of Le(a) and Le(x) antigens, too, were employed, namely neoglycolipids produced by coupling LcOse4 or NeoLcOse4 oligosaccharides to L-alpha-phosphatidyl-ethanol-amine-dipalmitoyl. Our data indicate that human colorectal tumor tissue contains two highly active sialyltransferase enzymes, which are only weakly expressed in normal mucosa. These are a N-glycan-specific alpha 2,6-sialyltransferase, which was significantly increased in metastasizing tumors, and a Gal beta 1,3Gal-NAc-specific sialyltransferase, which was increased in tumors of early stages. A shift to enhanced alpha 2,6-sialylation of membrane glycoproteins during carcinogenesis was demonstrated by lectin ELISA analysis of magneto-bead separated tumor cells. Quantitative determination of specific sialyltransferase activities may be a sensitive tool for detection and monitoring of colon carcinoma.
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Affiliation(s)
- W Kemmner
- Institut für Biochemie II, Universität Heidelberg, Germany
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27
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Gessner P, Riedl S, Quentmaier A, Kemmner W. Enhanced activity of CMP-neuAc:Gal beta 1-4GlcNAc:alpha 2,6-sialyltransferase in metastasizing human colorectal tumor tissue and serum of tumor patients. Cancer Lett 1993; 75:143-9. [PMID: 8313349 DOI: 10.1016/0304-3835(93)90056-f] [Citation(s) in RCA: 91] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The activity of sialyltransferases with different linkage specificities, of a Gal beta 1-4GlcNAc:alpha 2,6-sialyltransferase and a Gal beta 1-4GlcNAc:alpha 2,3-sialyltransferase, was studied in human colorectal tumor tissue from surgical specimens, normal mucosa, liver and liver metastases, and serum of patients suffering from colorectal carcinomas. While alpha 2,3-specific activity was equally high in tumor and mucosa samples, the activity of the alpha 2,6-specific enzyme was increased in tumor tissue and particularly in metastasizing tumors. Also, compared to healthy individuals, serum of patients suffering from metastasizing tumors contained a significantly higher activity of the alpha 2,6-specific enzyme. These results demonstrate that specific sialyltransferase isoforms are expressed in metastasizing tumors and that determination of such isoforms may be a new means for tumor detection and monitoring.
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Affiliation(s)
- P Gessner
- Institut für Biochemie II, Universität Heidelberg, Germany
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28
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Abstract
Glycoproteins are widely distributed among species in soluble and membrane-bound forms, associated with many different functions. The heterogenous sugar moieties of glycoproteins are assembled in the endoplasmic reticulum and in the Golgi and are implicated in many roles that require further elucidation. Glycoprotein-bound oligosaccharides show significant changes in their structures and relative occurrences during growth, development, and differentiation. Diverse alterations of these carbohydrate chains occur in diseases such as cancer, metastasis, leukemia, inflammatory, and other diseases. Structural alterations may correlate with activities of glycosyltransferases that assemble glycans, but often the biochemical origin of these changes remains unclear. This suggests a multitude of biosynthetic control mechanisms that are functional in vivo but have not yet been unraveled by in vitro studies. The multitude of carbohydrate alterations observed in disease states may not be the primary cause but may reflect the growth and biochemical activity of the affected cell. However, knowledge of the control mechanisms in the biosynthesis of glycoprotein glycans may be helpful in understanding, diagnosing, and treating disease.
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Affiliation(s)
- I Brockhausen
- Department of Biochemistry, University of Toronto, Ontario, Canada
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29
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Dall'Olio F, Malagolini N, Serafini-Cessi F. The expression of soluble and cell-bound alpha 2,6 sialyltransferase in human colonic carcinoma CaCo-2 cells correlates with the degree of enterocytic differentiation. Biochem Biophys Res Commun 1992; 184:1405-10. [PMID: 1590800 DOI: 10.1016/s0006-291x(05)80039-7] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
alpha 2,6 sialyltransferase towards the N-acetyllactosaminyl sequence (alpha 2,6 ST, E.C. 2.4.99.1) is one of the major sialyltransferases in human colonic cells; it strongly increases in human colorectal tumors and is largely expressed in fetal and neonatal rat colon. In this study we demonstrate that human colon carcinoma CaCo-2 cells, which differentiate spontaneously into enterocytes when maintained confluent for several days, exhibit a very high expression of alpha 2,6 ST both in the cell-bound and soluble form. When the CaCo-2 cells were cultured on porous membranes the soluble alpha 2,6 ST was mainly detected in the medium collected from the chamber corresponding to the basolateral face of the monolayer. The soluble alpha 2,6 ST could be concentrated and purified from the alpha 2,3 sialyltransferase by affinity chromatography on Blue Sepharose.
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Affiliation(s)
- F Dall'Olio
- Dipartimento di Patologia Sperimentale dell'Università di Bologna, Italy
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