Polypeptide GalNAc-transferases, ST6GalNAc-transferase I, and ST3Gal-transferase I Expression in Gastric Carcinoma Cell Lines

Mucin O-glycosylation in cancer is characterized by aberrant expression of immature carbohydrate structures leading to exposure of simple mucin-type carbohydrate antigens and peptide epitopes. Glycosyltransferases controlling the initial steps of mucin O-glycosylation are responsible for the altered glycosylation observed in cancer. We studied the expression in gastric cell lines of six UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferases (GalNAc-T1, T2, T3, T4, T6, T11) that catalyze the initial key step in the regulation of mucin O-glycosylation, the transfer of GalNAc from UDP-GalNAc to serine and threonine residues. We also studied the expression of ST6GalNAc-I, the enzyme responsible for the synthesis of Sialyl-Tn antigen (NeuAcα2,6GalNAc) and the ST3Gal-I, the enzyme responsible for the synthesis of Sialyl-T antigen (NeuAcα2,3Galβ1,3GalNAc). This study was done using specific monoclonal antibodies, enzymatic assays, and RT-PCR. Our results showed that GalNAc-T1, -T2, and -T3 have an ubiquitous expression in all gastric cell lines, whereas GalNAc-T4, -T6, and -T11 show a restricted expression pattern. The immunoreactivity with MAb VU-2-G7 suggests that, apart from GalNAc-T4, another GalNAc transferase is involved in the glycosylation of the Thr in the PDTR region of the MUC1 tandem repeat. The expression of ST3Gal-I correlates with the expression of the Sialyl-T antigen in gastric cell lines and in the control cell lines studied. The expression of ST6GalNAc-I is low in gastric cell lines, in accordance with the low/absent expression of the Sialyl-Tn antigen.

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Terminal α1,4-linked N-acetylglucosamine in Helicobacter pylori-associated Intestinal Metaplasia of the Human Stomach and Gastric Carcinoma Cell Lines

Journal of Histochemistry & Cytochemistry ◽

10.1369/jhc.5a6836.2006 ◽

2006 ◽

Vol 54 (5) ◽

pp. 585-591 ◽

Cited By ~ 25

Author(s):

Bibiana Ferreira ◽

Nuno T. Marcos ◽

Leonor David ◽

Jun Nakayama ◽

Celso A. Reis

Keyword(s):

Helicobacter Pylori ◽

Gastric Carcinoma ◽

Cell Lines ◽

Carcinoma Cell ◽

Tn Antigen ◽

Gastric Carcinoma Cell ◽

Carcinoma Cell Lines ◽

Gastric Carcinoma Cell Lines ◽

Sialyl Tn Antigen ◽

Sialyl Tn

Helicobacter pylori (Hp) infection is associated with the development of gastric lesions including gastritis, intestinal metaplasia (IM), and gastric carcinoma. In humans, Hp is found almost exclusively in the foveolar epithelium of the gastric mucosa and rarely colonizes the deeper portions where mucous cells of the glands produce mucins with terminal α1, 4-GlcNAc O-glycans. This structure exerts antimicrobial activity against Hp. The development of IM in the stomach is characterized by Hp clearance from the metaplastic glands and by major alterations in the expression of mucins and mucin-carbohydrates. The present work evaluated whether terminal α1,4-GlcNAc and sialyl-Tn antigen are implicated in the process of Hp clearance from metaplastic glands by analyzing the expression of these antigens in different types of IM—complete ( n=12) and incomplete ( n=8)—and in gastric cell lines. Terminal α1,4-GlcNAc was not detected in IM except in a single foci of one case, indicating that this structure is not implicated in the clearance of Hp from IM, in contrast to what is observed in normal gastric mucosa. None of the gastric carcinoma cell lines studied showed terminal α1,4-GlcNAc, suggesting that they do not display a gastric gland mucous cell phenotype and therefore are useful models for in vitro Hp studies. Finally, sialyl-Tn antigen colocalizes with MUC2 mucin and is present in all cases of complete and incomplete IM, suggesting that either or both can be implicated in Hp clearance from IM. (J Histochem Cytochem 54:585-591, 2006)

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Aberrant expression of MUC5AC and MUC6 gastric mucins and sialyl Tn antigen in intraepithelial neoplasms of the pancreas

Gastroenterology ◽

10.1053/gast.2002.36018 ◽

2002 ◽

Vol 123 (4) ◽

pp. 1052-1060 ◽

Cited By ~ 159

Author(s):

Grace E. Kim ◽

Han–Ik Bae ◽

Hee–Ug Park ◽

Shih–Fan Kuan ◽

Suzanne C. Crawley ◽

...

Keyword(s):

Tn Antigen ◽

Aberrant Expression ◽

Intraepithelial Neoplasms ◽

Sialyl Tn Antigen ◽

Sialyl Tn

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Faculty Opinions recommendation of Siglec-15 recognition of sialoglycans on tumor cell lines can occur independently of sialyl Tn antigen expression.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.738093259.793578188 ◽

2020 ◽

Author(s):

Peng Wu

Keyword(s):

Tumor Cell ◽

Cell Lines ◽

Antigen Expression ◽

Tumor Cell Lines ◽

Tn Antigen ◽

Sialyl Tn Antigen ◽

Sialyl Tn

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Predictive value of preoperative serum sialyl tn antigen levels in prognosis of patients with gastric cancer

Cancer ◽

10.1002/1097-0142(19930915)72:6<1836::aid-cncr2820720607>3.0.co;2-7 ◽

1993 ◽

Vol 72 (6) ◽

pp. 1836-1840 ◽

Cited By ~ 30

Author(s):

Ikuo Takahashi ◽

Yoshihiko Maehara ◽

Tetsuya Kusumoto ◽

Motofumi Yoshida ◽

Yoshihiro Kakeji ◽

...

Keyword(s):

Gastric Cancer ◽

Predictive Value ◽

Tn Antigen ◽

Preoperative Serum ◽

Sialyl Tn Antigen ◽

Sialyl Tn

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Siglec-15 recognition of sialoglycans on tumor cell lines can occur independently of sialyl Tn antigen expression

Glycobiology ◽

10.1093/glycob/cwaa048 ◽

2020 ◽

Cited By ~ 4

Author(s):

Gavuthami Murugesan ◽

Viviana G Correia ◽

Angelina S Palma ◽

Wengang Chai ◽

Chunxia Li ◽

...

Keyword(s):

Tumor Cells ◽

Cell Lines ◽

Antigen Expression ◽

Mapk Signaling ◽

Breast Cancer Cell Lines ◽

Cross Linking ◽

Monocytic Cell ◽

Immunosuppressive Microenvironment ◽

Sialyl Tn Antigen ◽

Sialyl Tn

Abstract Siglec-15 is a conserved sialic acid-binding Ig-like lectin expressed on osteoclast progenitors, which plays an important role in osteoclast development and function. It is also expressed by tumor-associated macrophages and by some tumors, where it is thought to contribute to the immunosuppressive microenvironment. It was shown previously that engagement of macrophage-expressed Siglec-15 with tumor cells expressing its ligand, sialyl Tn (sTn), triggered production of TGF-β. In the present study, we have further investigated the interaction between Siglec-15 and sTn on tumor cells and its functional consequences. Based on binding assays with lung and breast cancer cell lines and glycan-modified cells, we failed to see evidence for recognition of sTn by Siglec-15. However, using a microarray of diverse, structurally defined glycans, we show that Siglec-15 binds with higher avidity to sialylated glycans other than sTn or related antigen sequences. In addition, we were unable to demonstrate enhanced TGF-β secretion following co-culture of Siglec-15-expressing monocytic cell lines with tumor cells expressing sTn or following Siglec-15 cross-linking with monoclonal antibodies. However, we did observe activation of the SYK/MAPK signaling pathway following antibody cross-linking of Siglec-15 that may modulate the functional activity of macrophages.

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20 SIALYLTRANSFERASE GENE EXPRESSION IN GGTA1 KNOCKOUT PIGS

Reproduction Fertility and Development ◽

10.1071/rdv28n2ab20 ◽

2016 ◽

Vol 28 (2) ◽

pp. 140

Author(s):

G. A. Kim ◽

J.-X. Jin ◽

S. Lee ◽

A. Oh ◽

B. C. Lee

Keyword(s):

Gene Expression ◽

Somatic Cell ◽

Real Time ◽

Real Time Pcr ◽

Internal Standard ◽

Immune Rejection ◽

Tn Antigen ◽

Transgenic Pigs ◽

Sialyl Tn Antigen ◽

Sialyl Tn

It is considered that GGTA1 knockout (KO) pig production via somatic cell NT would overcome the problem of immune rejection after xenotransplantation. It is reported that although GGTA KO mice showed only a mild increase in sialyltransferase gene expression, GGTA1 deficiency in pig could increase the sialyltransferase activities, non-Gal epitope expression, consequently may raise non-Gal xenoantigenicity. Therefore, in the present study we investigated whether the expression level of Sia-containing glycoconjugate mRNA in transgenic pigs could be affected by knocking out the GGTA1 gene. Besides GGTA1 KO pigs, double genes overexpressing pigs (2TG) and GGTA1 KO with double genes overexpressing (KO+2TG) pigs were produced by somatic cell NT. For the present study, fibroblasts were isolated from wild-type pigs without gene modification, 2TG, GGTA1 KO, and KO+2TG pig. The GAPDH gene was used as an internal standard to normalise the real-time PCR (RT-qPCR) analysis reaction efficiency and to quantify mRNA in pigs-derived fibroblast. The expression levels were compared between them (RT-qPCR) in triplicate for each sample. Oligonucleotide primers for real-time PCR were designed for Hanganutziu-Deicher antigen (ST3Gal1–4, ST6Gal1) and Sialyl-Tn antigen (ST6GalNac1, ST6GalNac2, and ST6GalNac6) analysis. For statistical analysis, one-way ANOVA with Dunn’s multiple comparison test were used. The mRNA expression of GGTA1 KO and KO+2TG pig derived fibroblasts cells genes showed that ST3Gal1, ST3Gal2, ST3Gal3, and ST6Gal1 gene expression were significantly up-regulated compared to the wild and 2TG pigs (P < 0.05). However, ST3Gal4, Sialyl-Tn antigen including ST6GalNac1, ST6GalNac2, and ST6GalNac6 in KO+2TG pigs were not different compared with the wild pigs (P > 0.05), whereas only GGTA1 KO pigs showed significantly higher expressions than wild, 2TG, and KO+2TG pigs (P < 0.05). These results demonstrated that GGTA KO pig-derived cells exhibit a higher Hanganutziu-Deicher antigen on glycoprotein and glycolipid than controls, and KO+2TG pig exhibit no differences when compared with GGTA1 KO pig, indicating that they do not act as an immune antigen in xenograft. Overall, the increase in glycosyltransferase expression suggests a corresponding increase in the cell surface sialyation in GGTA KO pig cells. For xenotransplantation, KO+2TG pigs were more preferable because of absence of immune rejection for Sia-containing glycoconjugate on glycoprotein and glycolipid than GGTA KO pigs. This study was supported by the Ministry of Trade, Industry and Energy (#10048948), Korea IPET (#114059–3), Research Institute for Veterinary Science, TS Corporation, and the BK21 plus program.

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Products of Chemoenzymatic Synthesis Representing MUC1 Tandem Repeat Unit with T-, ST- or STn-antigen Revealed Distinct Specificities of Anti-MUC1 Antibodies

Scientific Reports ◽

10.1038/s41598-019-53052-1 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 7

Author(s):

Yayoi Yoshimura ◽

Kaori Denda-Nagai ◽

Yoshie Takahashi ◽

Izuru Nagashima ◽

Hiroki Shimizu ◽

...

Keyword(s):

Tandem Repeat ◽

Repeat Unit ◽

Structural Features ◽

T Antigen ◽

Enzyme Linked Immunosorbent Assay ◽

Serine Residue ◽

Tn Antigen ◽

Glycosylation Sites ◽

Sialyl Tn Antigen ◽

Cancer Diagnosis And Therapy

Abstract Anti-mucin1 (MUC1) antibodies have long been used clinically in cancer diagnosis and therapy and specific bindings of some of them are known to be dependent on the differential glycosylation of MUC1. However, a systematic comparison of the binding specificities of anti-MUC1 antibodies was not previously conducted. Here, a total of 20 glycopeptides including the tandem repeat unit of MUC1, APPAHGVTSAPDTRPAPGSTAPPAHGV with GalNAc (Tn-antigen), Galβ1-3GalNAc (T-antigen), NeuAcα2-3Galβ1-3GalNAc (sialyl-T-antigen), or NeuAcα2-6GalNAc (sialyl-Tn-antigen) at each threonine or serine residue were prepared by a combination of chemical glycopeptide synthesis and enzymatic extension of carbohydrate chains. These glycopeptides were tested by the enzyme-linked immunosorbent assay (ELISA) for their capacity to bind 13 monoclonal antibodies (mAbs) known to be specific for MUC1. The results indicated that anti-MUC1 mAbs have diverse specificities but can be classified into a few characteristic groups based on their binding pattern toward glycopeptides in some cases having a specific glycan at unique glycosylation sites. Because the clinical significance of some of these antibodies was already established, the structural features identified by these antibodies as revealed in the present study should provide useful information relevant to their further clinical use and the biological understanding of MUC1.

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