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Pap A, Kiraly IE, Medzihradszky KF, Darula Z. Multiple Layers of Complexity in O-Glycosylation Illustrated With the Urinary Glycoproteome. Mol Cell Proteomics 2022; 21:100439. [PMID: 36334872 PMCID: PMC9758497 DOI: 10.1016/j.mcpro.2022.100439] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Revised: 10/17/2022] [Accepted: 10/31/2022] [Indexed: 11/11/2022] Open
Abstract
While N-glycopeptides are relatively easy to characterize, O-glycosylation analysis is more complex. In this article, we illustrate the multiple layers of O-glycopeptide characterization that make this task so challenging. We believe our carefully curated dataset represents perhaps the largest intact human glycopeptide mixture derived from individuals, not from cell lines. The samples were collected from healthy individuals, patients with superficial or advanced bladder cancer (three of each group), and a single bladder inflammation patient. The data were scrutinized manually and interpreted using three different search engines: Byonic, Protein Prospector, and O-Pair, and the tool MS-Filter. Despite all the recent advances, reliable automatic O-glycopeptide assignment has not been solved yet. Our data reveal such diversity of site-specific O-glycosylation that has not been presented before. In addition to the potential biological implications, this dataset should be a valuable resource for software developers in the same way as some of our previously released data has been used in the development of O-Pair and O-Glycoproteome Analyzer. Based on the manual evaluation of the performance of the existing tools with our data, we lined up a series of recommendations that if implemented could significantly improve the reliability of glycopeptide assignments.
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Affiliation(s)
- Adam Pap
- Laboratory of Proteomics Research, Biological Research Centre, Eotvos Lorand Research Network (ELKH) Szeged, Hungary
| | | | - Katalin F. Medzihradszky
- Laboratory of Proteomics Research, Biological Research Centre, Eotvos Lorand Research Network (ELKH) Szeged, Hungary,For correspondence: Zsuzsanna Darula; Katalin F. Medzihradszky
| | - Zsuzsanna Darula
- Laboratory of Proteomics Research, Biological Research Centre, Eotvos Lorand Research Network (ELKH) Szeged, Hungary,Single Cell Omics Advanced Core Facility, Hungarian Centre of Excellence for Molecular Medicine Szeged, Hungary,For correspondence: Zsuzsanna Darula; Katalin F. Medzihradszky
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2
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Occurrence of a D-arabinose-containing complex-type free-N-glycan in the urine of cancer patients. Sci Rep 2022; 12:4889. [PMID: 35318379 PMCID: PMC8941101 DOI: 10.1038/s41598-022-08790-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Accepted: 03/14/2022] [Indexed: 11/11/2022] Open
Abstract
Urinary free-glycans are promising markers of disease. In this study, we attempted to identify novel tumor markers by focusing on neutral free-glycans in urine. Free-glycans extracted from the urine of normal subjects and cancer patients with gastric, colorectal, pancreatic and bile duct were fluorescently labeled with 2-aminopyridine. Profiles of these neutral free-glycans constructed using multidimensional high performance liquid chromatography separation were compared between normal controls and cancer patients. The analysis identified one glycan in the urine of cancer patients with a unique structure, which included a pentose residue. To reveal the glycan structure, the linkage fashion, monosaccharide species and enantiomer of the pentose were analyzed by high performance liquid chromatography and mass spectrometry combined with several chemical treatments. The backbone of the glycan was a monoantennary complex-type free-N-glycan containing β1,4-branch. The pentose residue was attached to the antennal GlcNAc and released by α1,3/4-l-fucosidase. Intriguingly, the pentose residue was consistent with d-arabinose. Collectively, this glycan structure was determined to be Galβ1-4(d-Araβ1-3)GlcNAcβ1-4Manα1-3Manβ1-4GlcNAc-PA. Elevation of d-arabinose-containing free-glycans in the urine of cancer patients was confirmed by selected reaction monitoring. This is the first study to unequivocally show the occurrence of a d-arabinose-containing oligosaccharide in human together with its detailed structure.
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3
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Recent advances and trends in sample preparation and chemical modification for glycan analysis. J Pharm Biomed Anal 2022; 207:114424. [PMID: 34653745 DOI: 10.1016/j.jpba.2021.114424] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2021] [Revised: 10/05/2021] [Accepted: 10/05/2021] [Indexed: 12/26/2022]
Abstract
Growing significance of glycosylation in protein functions has accelerated the development of methodologies for detection, identification, and characterization of protein glycosylation. In the past decade, glycobiology research has been advanced by innovative techniques with further progression in the post-genome era. Although significant technical progress has been made in terms of analytical throughput, comprehensiveness, and sensitivity, most methods for glycosylation analysis still require laborious and time-consuming sample preparation tasks. Additionally, sample preparation methods that are focused on specific glycan(s) require an in-depth understanding of various issues in glycobiology. In this review, modern sample preparation and chemical modification methods for the structural and quantitative glycan analyses together with the challenges and advantages of recent sample preparation methods are summarized. The techniques presented herein can facilitate the exploration of biomarkers, understanding of unknown glycan functions, and development of biopharmaceuticals.
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4
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Groux‐Degroote S, Vicogne D, Cogez V, Schulz C, Harduin‐Lepers A. B4GALNT2 Controls Sd
a
and SLe
x
Antigen Biosynthesis in Healthy and Cancer Human Colon. Chembiochem 2021. [DOI: 10.1002/cbic.202100363
expr 800938655 + 862139822] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/16/2023]
Affiliation(s)
- Sophie Groux‐Degroote
- Univ. Lille CNRS UMR 8576 UGSF Unité de Glycobiologie Structurale et Fonctionnelle 59000 Lille France
| | - Dorothée Vicogne
- Univ. Lille CNRS UMR 8576 UGSF Unité de Glycobiologie Structurale et Fonctionnelle 59000 Lille France
| | - Virginie Cogez
- Univ. Lille CNRS UMR 8576 UGSF Unité de Glycobiologie Structurale et Fonctionnelle 59000 Lille France
| | - Céline Schulz
- Univ. Lille CNRS UMR 8576 UGSF Unité de Glycobiologie Structurale et Fonctionnelle 59000 Lille France
| | - Anne Harduin‐Lepers
- Univ. Lille CNRS UMR 8576 UGSF Unité de Glycobiologie Structurale et Fonctionnelle 59000 Lille France
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5
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Groux-Degroote S, Vicogne D, Cogez V, Schulz C, Harduin-Lepers A. B4GALNT2 Controls Sd a and SLe x Antigen Biosynthesis in Healthy and Cancer Human Colon. Chembiochem 2021; 22:3381-3390. [PMID: 34397142 PMCID: PMC9290495 DOI: 10.1002/cbic.202100363] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Revised: 08/11/2021] [Indexed: 12/30/2022]
Abstract
The Sda carbohydrate antigen and the corresponding biosynthetic enzyme B4GALNT2 are primarily expressed in human normal colonic mucosa and are down‐regulated to variable degrees in colon cancer. On the other hand, the tumor associated antigen SLex is not detected in the healthy colon and is upregulated in colon cancer. High level of B4GALNT2 gene expression appears to be a good marker of prognosis in colon cancer; however, the molecular mechanisms regulating these carbohydrate antigens’ expression are still poorly understood. We review here the most recent progress made towards understanding this balanced expression of blood group carbohydrate epitopes Sda and SLex. In particular in recent years, we have attained a better understanding of genetic and epigenetic regulation of the B4GALNT2 gene and of the subcellular fate of B4GALNT2 isoforms.
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Affiliation(s)
- Sophie Groux-Degroote
- Univ. Lille, CNRS, UMR 8576, UGSF, Unité de Glycobiologie Structurale et Fonctionnelle, 59000, Lille, France
| | - Dorothée Vicogne
- Univ. Lille, CNRS, UMR 8576, UGSF, Unité de Glycobiologie Structurale et Fonctionnelle, 59000, Lille, France
| | - Virginie Cogez
- Univ. Lille, CNRS, UMR 8576, UGSF, Unité de Glycobiologie Structurale et Fonctionnelle, 59000, Lille, France
| | - Céline Schulz
- Univ. Lille, CNRS, UMR 8576, UGSF, Unité de Glycobiologie Structurale et Fonctionnelle, 59000, Lille, France
| | - Anne Harduin-Lepers
- Univ. Lille, CNRS, UMR 8576, UGSF, Unité de Glycobiologie Structurale et Fonctionnelle, 59000, Lille, France
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6
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The Cancer-Associated Antigens Sialyl Lewis a/x and Sd a: Two Opposite Faces of Terminal Glycosylation. Cancers (Basel) 2021; 13:cancers13215273. [PMID: 34771437 PMCID: PMC8582462 DOI: 10.3390/cancers13215273] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Revised: 10/11/2021] [Accepted: 10/19/2021] [Indexed: 12/12/2022] Open
Abstract
Simple Summary The glycosyltransferase β1,4-N-acetylgalactosaminyltransferae 2 (B4GALNT2), product of the B4GALNT2 gene is responsible for the biosynthesis of the carbohydrate antigen Sda. Both the enzyme and its cognate antigen display a restricted pattern of tissue expression and modulation in colorectal, gastric, and mammary cancers. In colorectal cancer, B4GALNT2 is generally downregulated, but patients displaying higher expression survive longer. The sialyl Lewisa and sialyl Lewisx antigens are associated with malignancy. Their biosynthesis and that of Sda are mutually exclusive. Forced expression of B4GALNT2 in colorectal cancer cell lines modulates the transcriptome towards lower malignancy, reducing stemness. These effects are independent of B4GALNT2-induced sLea/sLex inhibition. Thus, B4GALNT2 is a marker of better prognosis and a cancer-restraining enzyme in colorectal cancer, with a therapeutic potential. Abstract Terminal carbohydrate structures are particularly relevant in oncology because they can serve as cancer markers and alter the phenotype of cancer cells. The Sda antigen and the sialyl Lewisx and sialyl Lewisa (sLex and sLea) antigens are terminal structures whose biosynthesis is mutually exclusive. In this review, we describe the main features of the Sda antigen in cancer and its relationship with sLex/a antigens. Information was obtained from an extensive literature search and from The Cancer Genome Atlas (TCGA) public database. The Sda biosynthetic enzyme B4GALNT2 undergoes downregulation in colorectal (CRC) and stomach cancer, while it is ectopically expressed by a minority of breast cancer (BRCA) patients. High expression of B4GALNT2 is associated with better prognosis and a less malignant gene expression profile in CRC, while the opposite occurs in BRCA. The regulation of B4GALNT2 expression in CRC is multifactorial, involving gene methylation and miRNA expression. Forced expression of B4GALNT2 inhibited sLea/sLex and reduced malignancy and stemness in cells constitutively expressing sLex/a antigens. However, consistent effects were observed upon B4GALNT2 forced expression and in cells not expressing sLex/a antigens. Thus, B4GALNT2 and the Sda antigen exert a tumor-restraining activity in CRC and probably other gastrointestinal cancers, independently of sLex/a antigens.
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7
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Tikhonov A, Smoldovskaya O, Feyzkhanova G, Kushlinskii N, Rubina A. Glycan-specific antibodies as potential cancer biomarkers: a focus on microarray applications. Clin Chem Lab Med 2021; 58:1611-1622. [PMID: 32324152 DOI: 10.1515/cclm-2019-1161] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2019] [Accepted: 03/10/2020] [Indexed: 02/06/2023]
Abstract
Glycosylation is one of the most common posttranslational modifications of proteins and lipids. In the case of tumors, cell transformation accompanied by aberrant glycosylation results in the expression of tumor-associated glycans that promote tumor invasion. As part of the innate immunity, anti-glycan antibodies recognize tumor-associated glycans, and these antibodies can be present in the bloodstream in the early stages of cancer. Recently, anti-glycan antibody profiles have been of interest in various cancer studies. Novel advantages in the field of analytical techniques have simplified the analysis of anti-glycan antibodies and made it easier to have more comprehensive knowledge about their functions. One of the robust approaches for studying anti-glycan antibodies engages in microarray technology. The analysis of glycan microarrays can provide more expanded information to simultaneously specify or suggest the role of antibodies to a wide variety of glycans in the progression of different diseases, therefore making it possible to identify new biomarkers for diagnosing cancer and/or the state of the disease. Thus, in this review, we discuss antibodies to various glycans, their application for diagnosing cancer and one of the most promising tools for the investigation of these molecules, microarrays.
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Affiliation(s)
- Aleksei Tikhonov
- Laboratory of Biological Microchips, Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, Russia
| | - Olga Smoldovskaya
- Laboratory of Biological Microchips, Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, Russia
| | - Guzel Feyzkhanova
- Laboratory of Biological Microchips, Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, Russia
| | - Nikolay Kushlinskii
- Laboratory of Clinical Biochemistry, Federal State Budgetary Institution «N.N. Blokhin National Medical Research Center of Oncology» оf the Ministry of Health of the Russian Federation, Moscow, Russia
| | - Alla Rubina
- Laboratory of Biological Microchips, Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, Russia
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8
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Tabang DN, Ford M, Li L. Recent Advances in Mass Spectrometry-Based Glycomic and Glycoproteomic Studies of Pancreatic Diseases. Front Chem 2021; 9:707387. [PMID: 34368082 PMCID: PMC8342852 DOI: 10.3389/fchem.2021.707387] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Accepted: 07/12/2021] [Indexed: 12/14/2022] Open
Abstract
Modification of proteins by glycans plays a crucial role in mediating biological functions in both healthy and diseased states. Mass spectrometry (MS) has emerged as the most powerful tool for glycomic and glycoproteomic analyses advancing knowledge of many diseases. Such diseases include those of the pancreas which affect millions of people each year. In this review, recent advances in pancreatic disease research facilitated by MS-based glycomic and glycoproteomic studies will be examined with a focus on diabetes and pancreatic cancer. The last decade, and especially the last five years, has witnessed developments in both discovering new glycan or glycoprotein biomarkers and analyzing the links between glycans and disease pathology through MS-based studies. The strength of MS lies in the specificity and sensitivity of liquid chromatography-electrospray ionization MS for measuring a wide range of biomolecules from limited sample amounts from many sample types, greatly enhancing and accelerating the biomarker discovery process. Furthermore, imaging MS of glycans enabled by matrix-assisted laser desorption/ionization has proven useful in complementing histology and immunohistochemistry to monitor pancreatic disease progression. Advances in biological understanding and analytical techniques, as well as challenges and future directions for the field, will be discussed.
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Affiliation(s)
- Dylan Nicholas Tabang
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, United States
| | - Megan Ford
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI, United States
| | - Lingjun Li
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, United States.,School of Pharmacy, University of Wisconsin-Madison, Madison, WI, United States
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9
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Hanzawa K, Tanaka-Okamoto M, Murakami H, Mukai M, Takahashi H, Omori T, Ikezawa K, Ohkawa K, Ohue M, Miyamoto Y. Investigation of acidic free-glycans in urine and their alteration in cancer. Glycobiology 2020; 31:391-409. [PMID: 33135073 PMCID: PMC8091460 DOI: 10.1093/glycob/cwaa100] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Revised: 10/20/2020] [Accepted: 10/21/2020] [Indexed: 11/14/2022] Open
Abstract
Alterations to glycans in cancer patients have been used to identify novel tumor biomarkers. Most of these studies have focused on protein glycosylation but less attention has been paid to free-glycans. Here, we analyzed acidic free-glycans in the urine of cancer patients to identify novel tumor marker candidates. Specifically, urine samples were collected from patients with gastric cancer, pancreatic cancer and cholangiocarcinoma as well as normal controls. The free-glycans were extracted from creatinine-adjusted urine and fluorescently labeled with 2-aminopyridine. Initially, we performed profiling of urinary free-glycans by high-performance liquid chromatography and mass spectrometry with enzymatic and chemical degradation. More than 100 glycans, including novel structures, were identified. The chromatographic peaks suggested some of these glycans were present at elevated levels in cancer patients. To verify cancer-associated alterations, we compared the glycan levels between cancer patients and normal controls by selected reaction monitoring. Representative structures of glycans with elevated levels in cancer patients included the following: small glycans related to sialyllactose; sialyl Lewis X; lactose- and N-acetyllactosamine (LacNAc) type-II-core glycans with LacNAc (type-I or II)-extensions and modifications of α1,3/4-fucose and/or 6-sulfate on the Glc/GlcNAc; free-N-glycans containing sialylation or β1,6-branch of 6-sulfo Lewis X; novel NeuAcα2-3Galβ1-4(+/−Fucα1-3) Xylα1-3Glc glycans. Our results provide further insight into urinary free-glycans and suggest the potential utility of these compounds as tumor markers.
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Affiliation(s)
- Ken Hanzawa
- Department of Molecular Biology, Osaka International Cancer Institute, 3-1-69 Otemae, Chuo-ku, Osaka 541-8567, Japan
| | - Miki Tanaka-Okamoto
- Department of Molecular Biology, Osaka International Cancer Institute, 3-1-69 Otemae, Chuo-ku, Osaka 541-8567, Japan
| | - Hiroko Murakami
- Department of Molecular Biology, Osaka International Cancer Institute, 3-1-69 Otemae, Chuo-ku, Osaka 541-8567, Japan
| | - Mikio Mukai
- Department of Medical Checkup, Osaka International Cancer Institute, 3-1-69 Otemae, Chuo-ku, Osaka 541-8567, Japan
| | - Hidenori Takahashi
- Department of Gastroenterological Surgery, Osaka International Cancer Institute, 3-1-69 Otemae, Chuo-ku, Osaka 541-8567, Japan
| | - Takeshi Omori
- Department of Gastroenterological Surgery, Osaka International Cancer Institute, 3-1-69 Otemae, Chuo-ku, Osaka 541-8567, Japan
| | - Kenji Ikezawa
- Department of Hepatobiliary and Pancreatic Oncology, Osaka International Cancer Institute, 3-1-69 Otemae, Chuo-ku, Osaka 541-8567, Japan
| | - Kazuyoshi Ohkawa
- Department of Hepatobiliary and Pancreatic Oncology, Osaka International Cancer Institute, 3-1-69 Otemae, Chuo-ku, Osaka 541-8567, Japan
| | - Masayuki Ohue
- Department of Gastroenterological Surgery, Osaka International Cancer Institute, 3-1-69 Otemae, Chuo-ku, Osaka 541-8567, Japan
| | - Yasuhide Miyamoto
- Department of Molecular Biology, Osaka International Cancer Institute, 3-1-69 Otemae, Chuo-ku, Osaka 541-8567, Japan
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Papi F, Pâris A, Lafite P, Daniellou R, Nativi C. Synthesis of an STnThr analogue, structurally based on a TnThr antigen mimetic. Org Biomol Chem 2020; 18:7366-7372. [PMID: 32924046 DOI: 10.1039/d0ob01749c] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The monosaccharide Tn and the disaccharide STn are tumor antigens with similar structures and common biosynthetic pathways. Both are always over-expressed simultaneously on tumor cell surfaces. We report herein the efficient synthesis of the STnThr antigen analogue 2, featuring the immunogenic TnThr mimetic 1 aglycon. Analogously to the native STn, 2 is recognized by the influenza N1 neuraminidase. A model of the N1·2 complex showed the sialyl moiety of 2 well nested in the active site pocket, with docking unaffected by the rigid aglycon. The analogue 2 is, therefore, in association with mimetic 1, a good determinant for the design of new multiantigen cancer vaccines.
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Affiliation(s)
- Francesco Papi
- Department of Chemistry, University of Florence, via della Lastruccia, 3-13, I-50119 Sesto F.no (FI), Italy.
| | - Arnaud Pâris
- Institut de Chimie Organique et Analytique (ICOA), Université d'Orléans/CNRS, UMR 7311, BP 6759, F-45067, Orléans Cedex 2, France
| | - Pierre Lafite
- Institut de Chimie Organique et Analytique (ICOA), Université d'Orléans/CNRS, UMR 7311, BP 6759, F-45067, Orléans Cedex 2, France
| | - Richard Daniellou
- Institut de Chimie Organique et Analytique (ICOA), Université d'Orléans/CNRS, UMR 7311, BP 6759, F-45067, Orléans Cedex 2, France
| | - Cristina Nativi
- Department of Chemistry, University of Florence, via della Lastruccia, 3-13, I-50119 Sesto F.no (FI), Italy.
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Stenfelt L, Hellberg Å, Möller M, Thornton N, Larson G, Olsson ML. Missense mutations in the C-terminal portion of the B4GALNT2-encoded glycosyltransferase underlying the Sd(a-) phenotype. Biochem Biophys Rep 2019; 19:100659. [PMID: 31367682 PMCID: PMC6646742 DOI: 10.1016/j.bbrep.2019.100659] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Revised: 06/16/2019] [Accepted: 06/19/2019] [Indexed: 01/02/2023] Open
Abstract
Sda is a high-frequency carbohydrate histo-blood group antigen, GalNAcβ1-4(NeuAcα2-3)Galβ, implicated in pathogen invasion, cancer, xenotransplantation and transfusion medicine. Complete lack of this glycan epitope results in the Sd(a−) phenotype observed in 4% of individuals who may produce anti-Sda. A candidate gene (B4GALNT2), encoding a Sda-synthesizing β-1,4-N-acetylgalactosaminyltransferase (β4GalNAc-T2), was cloned in 2003 but the genetic basis of human Sda deficiency was never elucidated. Experimental and bioinformatic approaches were used to identify and characterize B4GALNT2 variants in nine Sd(a−) individuals. Homozygosity for rs7224888:T > C dominated the cohort (n = 6) and causes p.Cys466Arg, which targets a highly conserved residue located in the enzymatically active domain and is judged deleterious to β4GalNAc-T2. Its allele frequency was 0.10–0.12 in different cohorts. A Sd(a−) compound heterozygote combined rs7224888:T > C with a splice-site mutation, rs72835417:G > A, predicted to alter splicing and occurred at a frequency of 0.11–0.12. Another compound heterozygote had two rare nonsynonymous variants, rs148441237:A > G (p.Gln436Arg) and rs61743617:C > T (p.Arg523Trp), in trans. One sample displayed no differences compared to Sd(a+). When investigating linkage disequilibrium between B4GALNT2 variants, we noted a 32-kb block spanning intron 9 to the intergenic region downstream of B4GALNT2. This block includes RP11-708H21.4, a long non-coding RNA recently reported to promote tumorigenesis and poor prognosis in colon cancer. The expression patterns of B4GALNT2 and RP11-708H21.4 correlated extremely well in >1000 cancer cell lines. In summary, we identified a connection between variants of the cancer-associated B4GALNT2 gene and Sda, thereby establishing a new blood group system and opening up for the possibility to predict Sd(a+) and Sd(a‒) phenotypes by genotyping.
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Affiliation(s)
- Linn Stenfelt
- Hematology and Transfusion Medicine, Department of Laboratory Medicine, Lund University, BMC C14, Sölvegatan 19, SE-22184, Lund, Sweden
| | - Åsa Hellberg
- Department of Clinical Immunology and Transfusion Medicine, Laboratory Medicine, Office of Medical Service, F-blocket, Klinikgatan 21, SE-22185, Lund, Sweden
| | - Mattias Möller
- Hematology and Transfusion Medicine, Department of Laboratory Medicine, Lund University, BMC C14, Sölvegatan 19, SE-22184, Lund, Sweden
| | - Nicole Thornton
- International Blood Group Reference Laboratory, NHS Blood and Transplant, 500, North Bristol Park, Filton, Bristol, BS34 7QH, United Kingdom
| | - Göran Larson
- Department of Laboratory Medicine, Institute of Biomedicine, Sahlgrenska Academy at the University of Gothenburg, Bruna Stråket 16, SE-41345, Gothenburg, Sweden.,Laboratory of Clinical Chemistry, Sahlgrenska University Hospital, Bruna Stråket 16, SE-41345, Gothenburg, Sweden
| | - Martin L Olsson
- Hematology and Transfusion Medicine, Department of Laboratory Medicine, Lund University, BMC C14, Sölvegatan 19, SE-22184, Lund, Sweden.,Department of Clinical Immunology and Transfusion Medicine, Laboratory Medicine, Office of Medical Service, F-blocket, Klinikgatan 21, SE-22185, Lund, Sweden
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