251
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Chen L, Couchman JR, Smith J, Woods A. Molecular characterization of chicken syndecan-2 proteoglycan. Biochem J 2002; 366:481-90. [PMID: 12038962 PMCID: PMC1222803 DOI: 10.1042/bj20020711] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2002] [Revised: 05/29/2002] [Accepted: 05/31/2002] [Indexed: 12/27/2022]
Abstract
A partial syndecan-2 sequence (147 bp) was obtained from chicken embryonic fibroblast poly(A)+ RNA by reverse transcription-PCR. This partial sequence was used to produce a 5'-end-labelled probe. A chicken liver cDNA library was screened with this probe, and overlapping clones were obtained encompassing the entire cDNA of 3 kb. The open reading frame encodes a protein of 201 amino acids. The cytoplasmic domain is identical with that of mammalian syndecan-2, and highly similar to those of Xenopus laevis and zebrafish syndecan-2. The transmembrane domain is identical with that of mammalian and zebrafish syndecan-2, and highly similar to that of Xenopus laevis syndecan-2. The ectodomain is 45-62% identical with that of zebrafish, Xenopus laevis and mammalian syndecan-2. Two coding single nucleotide polymorphisms were observed. In vitro transcription and translation yielded a product of 30 kDa. Western blotting of chicken embryonic fibroblast cell lysates with species-specific monoclonal antibody mAb 8.1 showed that chicken syndecan-2 is substituted with heparan sulphate, and that the major form of chicken syndecan-2 isolated from chicken fibroblasts is consistent with the formation of SDS-resistant dimers, which is common for syndecans. A 5'-end-labelled probe hybridized to two mRNA species in chicken embryonic fibroblasts, while Northern analysis with poly(A)+ RNAs from different tissues of chicken embryos showed wide and distinct distributions of chicken syndecan-2 during embryonic development. This pattern was different from that reported for syndecan-4, but consistent with the roles of syndecan-2 in neural maturation and in mesenchymal-matrix interactions.
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Affiliation(s)
- Ligong Chen
- Department of Cell Biology and Cell Adhesion and Matrix Research Center, University of Alabama at Birmingham, Birmingham, AL 35294, USA
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252
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Yang Y, Yaccoby S, Liu W, Langford JK, Pumphrey CY, Theus A, Epstein J, Sanderson RD. Soluble syndecan-1 promotes growth of myeloma tumors in vivo. Blood 2002; 100:610-7. [PMID: 12091355 DOI: 10.1182/blood.v100.2.610] [Citation(s) in RCA: 151] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Syndecan-1 (CD138) is a transmembrane heparan sulfate-bearing proteoglycan expressed by most myeloma plasma cells that regulates adhesion, migration, and growth factor activity. In patients with myeloma, shed syndecan-1 accumulates in the bone marrow, and high levels of syndecan-1 in the serum are an indicator of poor prognosis. To test the effect of soluble syndecan-1 on tumor cell growth and dissemination, ARH-77 B-lymphoid cells were engineered to produce a soluble form of syndecan-1. Controls included vector only (neo)-transfected cells and cells transfected with full-length syndecan-1 complementary DNA that codes for the cell surface form of syndecan-1. Assays reveal that all 3 transfectants have similar growth rates in vitro, but cells expressing soluble syndecan-1 are hyperinvasive in collagen gels relative to controls. When injected into the marrow of human bones that were implanted in severe combined immunodeficient mice, tumors formed by cells expressing soluble syndecan-1 grow faster than tumors formed by neo-transfected cells or by cells expressing cell surface syndecan-1. In addition, cells bearing cell surface syndecan-1 exhibit a diminished capacity to establish tumors within the mice as compared with both neo- and soluble syndecan-1-transfected cells. Tumor cell dissemination to a contralateral human bone is detected significantly more often in the tumors producing soluble syndecan-1 than in controls. Thus, high levels of soluble syndecan-1 present in patients with myeloma may contribute directly to the growth and dissemination of the malignant cells and thus to poor prognosis.
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Affiliation(s)
- Yang Yang
- Arkansas Cancer Research Center, Department of Pathology, and the Myeloma Institute for Research and Therapy, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
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253
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Tímár J, Lapis K, Dudás J, Sebestyén A, Kopper L, Kovalszky I. Proteoglycans and tumor progression: Janus-faced molecules with contradictory functions in cancer. Semin Cancer Biol 2002; 12:173-86. [PMID: 12083848 DOI: 10.1016/s1044-579x(02)00021-4] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Understanding the details of the molecular mechanism of tumor dissemination revealed that several proteoglycan species are involved in the process but their role can be described as Janus-faced. One level of proteoglycan alterations is at the expression of their genes coding for the core protein. Characteristically, in progressing tumors two patterns emerged: loss or neoexpression of surface proteoglycans (PG) depending on the initial expression pattern of the cell type of origin. The situation is similarly complex concerning the changes of glycosaminoglycan (GAG) of the PG during tumor progression. This is due to the fact that the majority of PGs involved is hybrid molecule meaning that their core protein can be glycanated both with chondroitin and heparan sulfate. However, such an alteration in glycanation of PG may fundamentally change the function of the molecule, especially the one operating at the cell surface. Among the extracellular PGs, decorin emerged as inhibitor of progression while perlecan as a promoter of the process. Analysis of the available data indicate that during metastatization tumor cells must express at least one cell surface HSPG species from the syndecan-glypican-CD44v3 group. Furthermore, the HS-chain of these proteoglycan(s) carry important molecular signatures (suphution or epimerization patterns). Experimental data suggest that tumor cell surface heparan sulfate (PG) may provide a target for specific anti-metastatic interventions.
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Affiliation(s)
- József Tímár
- Department of Tumor Progression, National Institute of Oncology, Budapest, Hungary.
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254
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Horowitz A, Tkachenko E, Simons M. Fibroblast growth factor-specific modulation of cellular response by syndecan-4. J Cell Biol 2002; 157:715-25. [PMID: 12011116 PMCID: PMC2173870 DOI: 10.1083/jcb.200112145] [Citation(s) in RCA: 122] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Proteoglycans participate in growth factor interaction with the cell surface through their heparan sulfate chains (HS), but it is not known if they are otherwise involved in growth factor signaling. It appears now that the syndecan-4 core protein, a transmembrane proteoglycan shown previously to bind phosphatidylinositol 4,5-bisphosphate (PIP(2)) and activate PKC alpha, participates in mediating the effects of fibroblast growth factor (FGF)2 on cell function. Mutations in the cytoplasmic tail of syndecan-4 that either reduced its affinity to PIP(2) (PIP(2)(-)) or disrupted its postsynaptic density 95, disk large, zona occludens-1 (PDZ)-dependent binding (PDZ(-)) produced a FGF2-specific dominant negative phenotype in endothelial cells as evidenced by the marked decline of their migration and proliferation rates and the impairment of their capacity to form tubes. In both cases, the molecular mechanism was determined to consist of a decrease in the syndecan-4-dependent activation of PKC alpha. This decrease was caused either by inhibition of FGF2-induced syndecan-4 dephosphorylation in the case of the PDZ(-) mutation or by disruption of basolateral targeting of syndecan-4 and its associated PDZ-dependent complex in the case of the PIP(2)(-) mutation. These results suggest that PKCalpha activation and PDZ-mediated formation of a serine/threonine phosphatase-containing complex by syndecan-4 are downstream events of FGF2 signaling.
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MESH Headings
- Animals
- Cell Membrane/drug effects
- Cell Membrane/metabolism
- Cells, Cultured
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/growth & development
- Endothelium, Vascular/metabolism
- Fibroblast Growth Factor 2/metabolism
- Fibroblast Growth Factor 2/pharmacology
- Fibroblast Growth Factors/metabolism
- Fibroblast Growth Factors/pharmacology
- Humans
- Isoenzymes/metabolism
- Membrane Glycoproteins/drug effects
- Membrane Glycoproteins/genetics
- Membrane Glycoproteins/metabolism
- Mitogen-Activated Protein Kinase Kinases
- Mutagenesis, Site-Directed/genetics
- Mutation/genetics
- Neovascularization, Physiologic/drug effects
- Neovascularization, Physiologic/physiology
- Phosphatidylinositol 4,5-Diphosphate/genetics
- Phosphatidylinositol 4,5-Diphosphate/metabolism
- Phosphorylation/drug effects
- Polymers/metabolism
- Protein Binding/genetics
- Protein Kinase C/metabolism
- Protein Kinase C-alpha
- Protein Serine-Threonine Kinases/genetics
- Protein Serine-Threonine Kinases/metabolism
- Protein Structure, Tertiary/genetics
- Proteoglycans/drug effects
- Proteoglycans/genetics
- Proteoglycans/metabolism
- Signal Transduction/drug effects
- Signal Transduction/physiology
- Syndecan-4
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Affiliation(s)
- Arie Horowitz
- Angiogenesis Research Center and Section of Cardiology, Department of Medicine, Dartmouth Medical School, Lebanon, NH 03756, USA.
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255
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Abstract
Breast cancer manifests itself in the mammary epithelium, yet there is a growing recognition that mammary stromal cells also play an important role in tumorigenesis. During its developmental cycle, the mammary gland displays many of the properties associated with breast cancer, and many of the stromal factors necessary for mammary development also promote or protect against breast cancer. Here we review our present knowledge of the specific factors and cell types that contribute to epithelial-stromal crosstalk during mammary development. To find cures for diseases like breast cancer that rely on epithelial-stromal crosstalk, we must understand how these different cell types communicate with each other.
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Affiliation(s)
| | - Zena Werb
- To whom correspondence should be addressed.
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256
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Bellin R, Capila I, Lincecum J, Park PW, Reizes O, Bernfield MR. Unlocking the secrets of syndecans: transgenic organisms as a potential key. Glycoconj J 2002; 19:295-304. [PMID: 12975608 DOI: 10.1023/a:1025352501148] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Heparan sulfate proteoglycans are known to modulate the activity of a large number of extracellular ligands thereby having the potential to regulate a great diversity of biological processes. The long-term studies in our laboratory have focused on the syndecans, one of the major cell surface heparan sulfate proteoglycan families. Most early work on syndecans involved biochemical studies that provided initial information on their structure and putative biological roles. In recent years, the development of transgenic organisms has allowed a more complete understanding of syndecan function. Studies with transgenic syndecan-1 and syndecan-3 mice have demonstrated an unforeseen role for syndecans in the regulation of feeding behavior. Syndecan-1 knockout mice display a reduced susceptibility to both Wnt-induced tumorigenesis and microbial pathogenesis. Experiments with Drosophila show that syndecan is first expressed upon cellularization in the early embryo, and may play a role in the early developmental stages of the fly. This review focuses on these diverse functions of the syndecans that have been elucidated by the use of transgenic mice and Drosophila as model systems.
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Affiliation(s)
- Robert Bellin
- Division of Newborn Medicine, Department of Pediatrics, Children's Hospital, Harvard Medical School, 300 Longwood Ave., Enders-950, Boston, MA 02115, USA.
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257
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Lilla J, Stickens D, Werb Z. Metalloproteases and adipogenesis: a weighty subject. THE AMERICAN JOURNAL OF PATHOLOGY 2002; 160:1551-4. [PMID: 12000705 PMCID: PMC1850859 DOI: 10.1016/s0002-9440(10)61100-5] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Affiliation(s)
- Jennifer Lilla
- Department of Anatomy, University of California, San Francisco, California 94143, USA
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258
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Affiliation(s)
- E M Selva
- Department of Genetics and Howard Hughes Medical Institute, Harvard Medical School, Boston, MA 02115, USA
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259
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Hsieh M, Johnson MA, Greenberg NM, Richards JS. Regulated expression of Wnts and Frizzleds at specific stages of follicular development in the rodent ovary. Endocrinology 2002; 143:898-908. [PMID: 11861511 DOI: 10.1210/endo.143.3.8684] [Citation(s) in RCA: 110] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Wnt ligands and Frizzled (Fz) G protein-coupled receptors impact cell fate, including embryonic development of the ovary. Because the role of these regulatory molecules during follicular development in the adult is not known, an RT-PCR survey was done. Wnt-4, Fz-4, and Fz-1 were among the transcripts detected, and each exhibited a specific pattern of expression. Fz-1 mRNA was low in preovulatory follicles of PMSG-treated mice but was increased within 4-12 h after an ovulatory surge of human CG. By in situ analysis, Fz-1 transcripts increased first in the theca cells and then in the granulosa cells of ovulating follicles but were low in corpora lutea. In contrast, Wnt-4, a critical factor in early ovarian development, was expressed in small preantral follicles. In addition, Wnt-4 was detected in preovulatory follicles and exhibited high levels in corpora lutea. A potential receptor for Wnt-4 in corpora lutea is Fz-4 that was also elevated in this tissue. Although Wnt-4 has been shown to function downstream of the PR in other tissues, Wnt-4 was not altered in follicles of PR-null mice that fail to ovulate. Rather expression of Fz-1 was lower in ovaries of PR knockout mice, compared with normal littermates. Thus, specific Wnt/Fz are expressed at distinct stages of follicular development, suggesting multiple functions for this signaling pathway in the ovary.
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MESH Headings
- Animals
- Blotting, Western
- Corpus Luteum/metabolism
- DNA Primers
- Female
- Frizzled Receptors
- Granulosa Cells/metabolism
- In Situ Hybridization
- Ligands
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Ovarian Follicle/physiology
- Ovary/metabolism
- Protein Biosynthesis
- Proteins/genetics
- Proto-Oncogene Proteins/biosynthesis
- Proto-Oncogene Proteins/genetics
- RNA, Messenger/biosynthesis
- RNA, Messenger/isolation & purification
- Rats
- Rats, Sprague-Dawley
- Receptors, Cell Surface
- Receptors, G-Protein-Coupled
- Receptors, Neurotransmitter/biosynthesis
- Receptors, Neurotransmitter/genetics
- Reverse Transcriptase Polymerase Chain Reaction
- Transcription, Genetic
- Wnt Proteins
- Zebrafish Proteins
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Affiliation(s)
- Minnie Hsieh
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas 77030, USA
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260
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Zhan F, Hardin J, Kordsmeier B, Bumm K, Zheng M, Tian E, Sanderson R, Yang Y, Wilson C, Zangari M, Anaissie E, Morris C, Muwalla F, van Rhee F, Fassas A, Crowley J, Tricot G, Barlogie B, Shaughnessy J. Global gene expression profiling of multiple myeloma, monoclonal gammopathy of undetermined significance, and normal bone marrow plasma cells. Blood 2002; 99:1745-57. [PMID: 11861292 DOI: 10.1182/blood.v99.5.1745] [Citation(s) in RCA: 486] [Impact Index Per Article: 22.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Bone marrow plasma cells (PCs) from 74 patients with newly diagnosed multiple myeloma (MM), 5 with monoclonal gammopathy of undetermined significance (MGUS), and 31 healthy volunteers (normal PCs) were purified by CD138(+) selection. Gene expression of purified PCs and 7 MM cell lines were profiled using high-density oligonucleotide microarrays interrogating about 6800 genes. On hierarchical clustering analysis, normal and MM PCs were differentiated and 4 distinct subgroups of MM (MM1, MM2, MM3, and MM4) were identified. The expression pattern of MM1 was similar to normal PCs and MGUS, whereas MM4 was similar to MM cell lines. Clinical parameters linked to poor prognosis, abnormal karyotype (P =.002) and high serum beta(2)-microglobulin levels (P =.0005), were most prevalent in MM4. Also, genes involved in DNA metabolism and cell cycle control were overexpressed in a comparison of MM1 and MM4. In addition, using chi(2) and Wilcoxon rank sum tests, 120 novel candidate disease genes were identified that discriminate normal and malignant PCs (P <.0001); many are involved in adhesion, apoptosis, cell cycle, drug resistance, growth arrest, oncogenesis, signaling, and transcription. A total of 156 genes, including FGFR3 and CCND1, exhibited highly elevated ("spiked") expression in at least 4 of the 74 MM cases (range, 4-25 spikes). Elevated expression of these 2 genes was caused by the translocation t(4;14)(p16;q32) or t(11;14)(q13;q32). Thus, novel candidate MM disease genes have been identified using gene expression profiling and this profiling has led to the development of a gene-based classification system for MM.
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Affiliation(s)
- Fenghuang Zhan
- Donna D. and Donald M. Lambert Laboratory of Myeloma Genetics, Myeloma Institute for Research and Therapy, University of Arkansas for Medical Sciences, Little Rock, 72205, USA
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261
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Derksen PWB, Keehnen RMJ, Evers LM, van Oers MHJ, Spaargaren M, Pals ST. Cell surface proteoglycan syndecan-1 mediates hepatocyte growth factor binding and promotes Met signaling in multiple myeloma. Blood 2002; 99:1405-10. [PMID: 11830493 DOI: 10.1182/blood.v99.4.1405] [Citation(s) in RCA: 211] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Heparan sulfate proteoglycans (HSPGs) play a crucial role in growth regulation by assembling signaling complexes and presenting growth factors to their cognate receptors. Within the immune system, expression of the HSPG syndecan-1 (CD138) is characteristic of terminally differentiated B cells, ie, plasma cells, and their malignant counterpart, multiple myeloma (MM). This study explored the hypothesis that syndecan-1 might promote growth factor signaling and tumor growth in MM. For this purpose, the interaction was studied between syndecan-1 and hepatocyte growth factor (HGF), a putative paracrine and autocrine regulator of MM growth. The study demonstrates that syndecan-1 is capable of binding HGF and that this growth factor is indeed a potent stimulator of MM survival and proliferation. Importantly, the interaction of HGF with heparan sulfate moieties on syndecan-1 strongly promotes HGF-mediated signaling, resulting in enhanced activation of Met, the receptor tyrosine kinase for HGF. Moreover, HGF binding to syndecan-1 promotes activation of the phosphatidylinositol 3-kinase/protein kinase B and RAS/mitogen-activated protein kinase pathways, signaling routes that have been implicated in the regulation of cell survival and proliferation, respectively. These results identify syndecan-1 as a functional coreceptor for HGF that promotes HGF/Met signaling in MM cells, thus suggesting a novel function for syndecan-1 in MM tumorigenesis.
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Affiliation(s)
- Patrick W B Derksen
- Department of Pathology, Academic Medical Center, University of Amsterdam, The Netherlands
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262
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Belting M, Borsig L, Fuster MM, Brown JR, Persson L, Fransson LA, Esko JD. Tumor attenuation by combined heparan sulfate and polyamine depletion. Proc Natl Acad Sci U S A 2002; 99:371-6. [PMID: 11752393 PMCID: PMC117567 DOI: 10.1073/pnas.012346499] [Citation(s) in RCA: 98] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Cells depend on polyamines for growth and their depletion represents a strategy for the treatment of cancer. Polyamines assemble de novo through a pathway sensitive to the inhibitor, alpha-difluoromethylornithine (DFMO). However, the presence of cell-surface heparan sulfate proteoglycans may provide a salvage pathway for uptake of circulating polyamines, thereby sparing cells from the cytostatic effect of DFMO. Here we show that genetic or pharmacologic manipulation of proteoglycan synthesis in the presence of DFMO inhibits cell proliferation in vitro and in vivo. In cell culture, mutant cells lacking heparan sulfate were more sensitive to the growth inhibitory effects of DFMO than wild-type cells or mutant cells transfected with the cDNA for the missing biosynthetic enzyme. Moreover, extracellular polyamines did not restore growth of mutant cells, but completely reversed the inhibitory effect of DFMO in wild-type cells. In a mouse model of experimental metastasis, DFMO provided in the water supply also dramatically diminished seeding and growth of tumor foci in the lungs by heparan sulfate-deficient mutant cells compared with the controls. Wild-type cells also formed tumors less efficiently in mice fed both DFMO and a xylose-based inhibitor of heparan sulfate proteoglycan assembly. The effect seemed to be specific for heparan sulfate, because a different xyloside known to affect only chondroitin sulfate did not inhibit tumor growth. Hence, combined inhibition of heparan sulfate assembly and polyamine synthesis may represent an additional strategy for cancer therapy.
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Affiliation(s)
- Mattias Belting
- Department of Cell and Molecular Biology, Biomedical Center C13, Lund University, P.O.B. 94, S-221 84 Lund, Sweden
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263
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Abstract
Heparan sulfate, a highly sulfated polysaccharide, is present on the surface of mammalian cells and in the extracellular matrix in large quantities. The sulfated monosaccharide sequences within heparan sulfate determine the protein binding specificity and regulate biological functions. Numerous viruses and parasites utilize cell surface heparan sulfate as receptors to infect target cells. Due to the structural complexity of heparan sulfate, it was considered a nonspecific cell surface receptor by interacting with the positive motifs of viral proteins. However, recent studies reveal that heparan sulfate plays multiple roles in assisting viral infection, and the activities in promoting viral infections require unique monosaccharide sequences, suggesting that heparan sulfate could serve as a specific receptor for viral infection. The currently available techniques for the structural analysis of heparan sulfate provide essential information about the specific roles of heparan sulfate in assisting viral infections. The knowledge accumulated in this fast growing field will permit us to have a better understanding of the mechanism of viral infection and will lead to the development of new antiviral agents.
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Affiliation(s)
- Jian Liu
- Division of Medicinal Chemistry and Natural Products, School of Pharmacy, University of North Carolina, Chapel Hill, North Carolina 27599, USA.
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264
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Radisky D, Muschler J, Bissell MJ. Order and disorder: the role of extracellular matrix in epithelial cancer. Cancer Invest 2002; 20:139-53. [PMID: 11852996 PMCID: PMC2933209 DOI: 10.1081/cnv-120000374] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Derek Radisky
- Life Sciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, MS 83-101, Berkeley, CA 94720
| | - John Muschler
- Life Sciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, MS 83-101, Berkeley, CA 94720
| | - Mina J. Bissell
- Life Sciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, MS 83-101, Berkeley, CA 94720
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265
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Ishiguro K, Kadomatsu K, Kojima T, Muramatsu H, Iwase M, Yoshikai Y, Yanada M, Yamamoto K, Matsushita T, Nishimura M, Kusugami K, Saito H, Muramatsu T. Syndecan-4 deficiency leads to high mortality of lipopolysaccharide-injected mice. J Biol Chem 2001; 276:47483-8. [PMID: 11585825 DOI: 10.1074/jbc.m106268200] [Citation(s) in RCA: 106] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Syndecan-4 is a transmembrane heparan sulfate proteoglycan belonging to the syndecan family. Following intraperitoneal injection of lipopolysaccharide (LPS), syndecan-4-deficient mice exhibited high mortality compared with wild-type controls. Severe endotoxin shock was observed in the deficient mice: systolic blood pressure and left ventricular fractional shortening were lower in the deficient mice than in the wild-type controls 9 h after LPS injection. Although histological examinations revealed no apparent differences between two groups, the plasma level of interleukin (IL)-1beta was higher in the deficient mice than in the wild-type controls 9 h after LPS injection. Consistent with the regulatory roles of syndecan-4, its expression in monocytes and endothelial cells of microvasculature increased in the wild-type mice after LPS administration. Although IL-1beta was produced to the same extent by macrophages from syndecan-4-deficient and wild-type mice after LPS stimulation, inhibition of its production by transforming growth factor-beta1 was impaired in the syndecan-4-deficient macrophages. These results indicate that syndecan-4 could be involved in prevention of endotoxin shock, at least partly through the inhibitory action of transforming growth factor-beta1 on IL-1beta production.
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Affiliation(s)
- K Ishiguro
- Department of Biochemistry, Nagoya University School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, Aichi, 466-8550, Japan
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266
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Abstract
The paradigm of cell surface proteoglycan function has been centered on the role of the ectoplasmic heparan sulfate (HS) chains as acceptors of a wide array of ligands, including extracellular matrix (ECM) proteins and soluble growth factors. Within this picture, the core proteins were assigned only a passive role of carrying the glycosaminoglycan (GAG) chains without direct participation in mediating outside-in signals generated by the binding of the above ligands. It appears now, however, that, side by side with the integrins and the tyrosine kinase receptors, the core proteins of the syndecan family of transmembrane proteoglycans are involved in signaling. The highly conserved tails of all the four members of the syndecan family contain a carboxy-terminal PDZ (Postsynaptic density 95, Disk large, Zona occludens-1)-binding motif, capable of forming multimolecular complexes through the binding of PDZ adaptor proteins. The cytoplasmic tail of the ubiquitously expressed syndecan-4 is distinct from the other syndecans in its capacity to bind phosphatidylinositol 4,5-bisphosphate (PIP2) and to activate protein kinase C (PKC) alpha. These properties may confer on syndecan-4 specific and unique signaling functions.
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Affiliation(s)
- M Simons
- Angiogenesis Research Center, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA 02215, USA.
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267
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Perreault N, Katz JP, Sackett SD, Kaestner KH. Foxl1 controls the Wnt/beta-catenin pathway by modulating the expression of proteoglycans in the gut. J Biol Chem 2001; 276:43328-33. [PMID: 11555641 DOI: 10.1074/jbc.m104366200] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Foxl1 is a winged helix transcription factor expressed in the mesenchyme of the gastrointestinal tract. Foxl1 null mice display severe structural defects in the epithelia of the stomach, duodenum, and jejunum. Here we addressed the molecular mechanisms by which Foxl1 controls gastrointestinal differentiation. First we showed that the abnormalities found in the epithelia of the null mice are the result of an increase in the number of proliferating cells and not a change in the rate of cell migration. Next we investigated the regulatory circuits affected by Foxl1. We focused on the Wnt/beta-catenin signaling pathway as a possible target of Foxl1 as it has been shown to play a central role in gastrointestinal proliferation. We demonstrated that Foxl1 activates the Wnt/beta-catenin pathway by increasing extracellular proteoglycans, which act as co-receptors for Wnt. Thus we establish that Foxl1 is involved in the regulation of the Wnt/beta-catenin pathway, providing a novel link in mesenchymal/epithelial cross-talk in the gut. Moreover, we provide the first example implicating proteoglycans in the regulation of cellular proliferation in the gastrointestinal tract.
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Affiliation(s)
- N Perreault
- Department of Genetics, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104-6145, USA
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268
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Abstract
Heparan sulfate proteoglycans (HSPGs) are widely distributed in mammalian tissues and involved in a number of processes related to malignancy. They are composed of a core protein to which chains of the glycosaminoglycan, heparan sulfate (HS), are attached. The existence of various classes of core protein, in addition to highly polymorphic HS chains, creates a superfamily of macromolecules with considerable diversity of structure and function. HSPGs interact with many proteins including growth factors, chemokines and structural proteins of the extracellular matrix to influence cell growth, differentiation, and the cellular response to the environment. The recent identification of two inherited syndromes that are associated with an increased cancer risk, and caused by mutations in HSPG-related genes, has intensified interest in these molecules. This review describes our current understanding of HSPGs in cancer and highlights new possibilities for therapeutic control.
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Affiliation(s)
- F H Blackhall
- Cancer Research Campaign Department of Medical Oncology, Christie Hospital and Paterson Institute for Cancer Research, Wilmslow Road, Withington, Manchester, M20 4BX, UK
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269
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Blair SS. Wnts, Signaling and Sulfates. Sci Signal 2001. [DOI: 10.1126/scisignal.1012001pe32] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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270
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Blair SS. Wnts, signaling and sulfates. SCIENCE'S STKE : SIGNAL TRANSDUCTION KNOWLEDGE ENVIRONMENT 2001; 2001:pe32. [PMID: 11579233 DOI: 10.1126/stke.2001.101.pe32] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Questions remain about the signaling pathways that control pattern formation during development. Blair describes how sulfated glycosaminoglycans affect several developmentally important signaling pathways, including Wnt-Wingless, Fibroblast growth factor, Hedgehog, and Bone morphogenetic protein-4 signaling. A new secreted sulfatase, Qsulf1, regulates the sensitivity of vertebrate cells to Wnts, possibly by modifying the sulfation of glycosaminoglycans.
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Affiliation(s)
- S S Blair
- Department of Zoology, University of Wisconsin, 250 N. Mills St., Madison, WI 53706, USA.
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271
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Veugelers M, De Cat B, Delande N, Esselens C, Bonk I, Vermeesch J, Marynen P, Fryns JP, David G. A 4-Mb BAC/PAC contig and complete genomic structure of the GPC5/GPC6 gene cluster on chromosome 13q32. Matrix Biol 2001; 20:375-85. [PMID: 11566272 DOI: 10.1016/s0945-053x(01)00143-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The glypicans compose a family of glycosylphosphatidylinositol-anchored heparan sulfate proteoglycans that may play a role in the control of cell division and growth regulation. So far, six members (GPC1-6) of this family are known in vertebrates. We report the construction of a high-resolution 4 Mb sequence-ready BAC/PAC contig of the GPC5/GPC6 gene cluster on chromosome region 13q32. The contig indicates that, like the GPC3/GPC4 genes on Xq26, GPC5 and GPC6 are arranged in tandem array. Both GPC5 and GPC6 are very large genes, with sizes well over 1 Mb. With a size of approximately 2 Mb, GPC5 would be the second largest human gene identified to date. Comparison of the long range gene organisation on 13q and Xq, suggests that these chromosomes share several regions of homology. Mutations and deletions affecting GPC3 are associated with the Simpson-Golabi-Behmel overgrowth syndrome. Mutational analysis of GPC5 and GPC6 in 19 patients with somatic overgrowth failed to reveal pathologic mutations in either of these genes, but identified several coding region polymorphisms.
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Affiliation(s)
- M Veugelers
- Laboratory for Glycobiology and Developmental Genetics, Center for Human Genetics, University of Leuven, Campus Gasthuisberg O&N6, Herestraat 49, B-3000 Leuven, Belgium
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272
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273
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Forsberg E, Kjellén L. Heparan sulfate: lessons from knockout mice. J Clin Invest 2001; 108:175-80. [PMID: 11457868 PMCID: PMC203035 DOI: 10.1172/jci13561] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Affiliation(s)
- E Forsberg
- Department of Medical Biochemistry and Microbiology, University of Uppsala, The Biomedical Center, Uppsala, Sweden.
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274
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Delehedde M, Lyon M, Sergeant N, Rahmoune H, Fernig DG. Proteoglycans: pericellular and cell surface multireceptors that integrate external stimuli in the mammary gland. J Mammary Gland Biol Neoplasia 2001; 6:253-73. [PMID: 11547896 DOI: 10.1023/a:1011367423085] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Proteoglycans consist of a core protein and an associated glycosaminoglycan (GAG) chain of heparan sulfate, chondroitin sulfate, dermatan sulfate or keratan sulfate, which are attached to a serine residue. The core proteins of cell surface proteoglycans may be transmembrane, e.g., syndecan, or GPI-anchored, e.g., glypican. Many different cell surface and matrix proteoglycan core proteins are expressed in the mammary gland and in mammary cells in culture. The level of expression of these core proteins, the structure of their GAG chains, and their degradation are regulated by many of the effectors that control the development and function of the mammary gland. Regulatory proteins of the mammary gland that bind GAG include many growth factors and morphogens (fibroblast growth factors, hepatocyte growth factor/scatter factor, members of the midkine family, wnts), matrix proteins (collagen, fibronectin, and laminin), enzymes (lipoprotein lipase) and microbial surface proteins. Structural diversity within GAG chains ensures that each protein-GAG interaction is as specific as necessary and a number of sequences of saccharides that recognize individual proteins have been elucidated. The GAG-protein interactions serve to regulate the signal output of growth factor receptor tyrosine kinase and hence cell fate as well as the storage and diffusion of extracellular protein effectors. In addition, GAGs clearly coordinate stromal and epithelial development, and they are active participants in mediating cell-cell and cell-matrix interactions. Since a single proteoglycan, even if it carries a single GAG chain, can bind multiple proteins, proteoglycans are also likely to act as multireceptors which promote the integration of cellular signals.
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Affiliation(s)
- M Delehedde
- School of Biological Sciences, University of Liverpool, United Kingdom
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275
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Park PW, Pier GB, Hinkes MT, Bernfield M. Exploitation of syndecan-1 shedding by Pseudomonas aeruginosa enhances virulence. Nature 2001; 411:98-102. [PMID: 11333985 DOI: 10.1038/35075100] [Citation(s) in RCA: 187] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Cell-surface heparan sulphate proteoglycans (HSPGs) are ubiquitous and abundant receptors/co-receptors of extracellular ligands, including many microbes. Their role in microbial infections is poorly defined, however, because no cell-surface HSPG has been clearly connected to the pathogenesis of a particular microbe. We have previously shown that Pseudomonas aeruginosa, through its virulence factor LasA, enhances the in vitro shedding of syndecan-1-the predominant cell-surface HSPG of epithelia. Here we show that shedding of syndecan-1 is also activated by P. aeruginosa in vivo, and that the resulting syndecan-1 ectodomains enhance bacterial virulence in newborn mice. Newborn mice deficient in syndecan-1 resist P. aeruginosa lung infection but become susceptible when given purified syndecan-1 ectodomains or heparin, but not when given ectodomain core protein, indicating that the ectodomain's heparan sulphate chains are the effectors. In wild-type newborn mice, inhibition of syndecan-1 shedding or inactivation of the shed ectodomain's heparan sulphate chains prevents lung infection. Our findings uncover a pathogenetic mechanism in which a host response to tissue injury-syndecan-1 shedding-is exploited to enhance microbial virulence apparently by modulating host defences.
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Affiliation(s)
- P W Park
- Division of Newborn Medicine, Department of Pediatrics, Children's Hospital, Harvard Medical School, Boston, MA 02115, USA.
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276
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Abstract
Because heparan sulfate proteoglycans mediate cell adhesion and control the activities of numerous growth and motility factors, they play a critical role in regulating the metastatic behavior of tumor cells. Due to their utilitarian nature, heparan sulfate proteoglycans may at times act as inhibitors of cell invasion and at other times as promoters of cell invasion, with their function being determined by their location (cell surface or extracellular matrix), the heparin-binding molecules they associate with, the presence of modifying enzymes (proteases, heparanases) and the precise structural characteristics of the proteoglycan. Also, the tissue type and pathophysiological state of the tumor influence proteogylcan function. This review summarizes our current knowledge of the role heparan sulfate proteoglycans play in regulating tumor cell metastasis, proposes mechanisms of how these molecules function and examines the potential for discovery of new therapeutic approaches designed to block metastatic cancer.
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Affiliation(s)
- R D Sanderson
- Department of Pathology, Arkansas Cancer Research Center, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA.
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277
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Abstract
The syndecans, cell surface heparan sulfate proteoglycans (HSPGs), bind numerous ligands via their HS glycosaminoglycan chains. The response to this binding is flavored by the identity of the core protein that bears the HS chains. Each of the syndecan core proteins has a short cytoplasmic domain that binds cytosolic regulatory factors. The syndecans also contain highly conserved transmembrane domain and extracellular domains for which important activities are slowly emerging. These protein domains, which will be the focus of this review, localize the syndecan to sites at the cell surface during development where they collaborate with other receptors to regulate signaling and cytoskeletal organization.
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Affiliation(s)
- A C Rapraeger
- Department of Pathology and Laboratory Medicine, University of Wisconsin-Madison, 1300 University Avenue, Madison, WI 53706, USA.
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278
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Affiliation(s)
- A Woods
- Department of Cell Biology, University of Alabama at Birmingham, Volker Hall 203A, 1530 3rd Avenue S., Birmingham, AL 35294-0019, USA.
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279
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Selvarajan S, Lund LR, Takeuchi T, Craik CS, Werb Z. A plasma kallikrein-dependent plasminogen cascade required for adipocyte differentiation. Nat Cell Biol 2001; 3:267-75. [PMID: 11231576 PMCID: PMC2802462 DOI: 10.1038/35060059] [Citation(s) in RCA: 120] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Here we show that plasma kallikrein (PKal) mediates a plasminogen (Plg) cascade in adipocyte differentiation. Ecotin, an inhibitor of serine proteases, inhibits cell-shape change, adipocyte-specific gene expression, and lipid accumulation during adipogenesis in culture. Deficiency of Plg, but not of urokinase or tissue-type plasminogen activator, suppresses adipogenesis during differentiation of 3T3-L1 cells and mammary-gland involution. PKal, which is inhibited by ecotin, is required for adipose conversion, Plg activation and 3T3-L1 differentiation. Human plasma lacking PKal does not support differentiation of 3T3-L1 cells. PKal is therefore a physiological regulator that acts in the Plg cascade during adipogenesis. We propose that the Plg cascade fosters adipocyte differentiation by degradation of the fibronectin-rich preadipocyte stromal matrix.
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Affiliation(s)
- S Selvarajan
- Department of Anatomy, Box 0452, University of California, 513 Parnasssus Avenue, San Francisco, California 94143, USA
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280
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Furukawa K, Takamiya K, Okada M, Inoue M, Fukumoto S, Furukawa K. Novel functions of complex carbohydrates elucidated by the mutant mice of glycosyltransferase genes. BIOCHIMICA ET BIOPHYSICA ACTA 2001; 1525:1-12. [PMID: 11342247 DOI: 10.1016/s0304-4165(00)00185-9] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Complex carbohydrates consist of carbohydrate moieties and protein or lipid portions, resulting in the formation of glycoproteins, proteoglycans or glycosphingolipids. The polymorphic carbohydrate structures are believed to contain profound biological implications which are important in cell-cell or cell-extracellular matrix interactions. A number of studies to delineate the roles of carbohydrates have been performed, and demonstrated definite changes in their profiles, cellular phenotypic changes or, sometimes, morphological and functional changes in tissues after modification of their structures. Recent successes in the isolation of glycosyltransferase genes and their modification enzyme genes has enabled clearer demonstrations of the roles of complex carbohydrates. In particular, genetic modification of glycosyltransferase genes in mice can elucidate the biological significances of their products in vivo. Here, we summarize recent advances in the understanding of the roles of complex carbohydrates provided from studies of gene knock-out mice of glycosyltransferase and modification enzyme genes focusing on novel functions which had not been expected.
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Affiliation(s)
- K Furukawa
- Department of Biochemistry II, Nagoya University School of Medicine, Japan
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281
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Abstract
Now that transmembrane signaling through primary cell-matrix receptors, integrins, is being elucidated, attention is turning to how integrin-ligand interactions can be modulated. Syndecans are transmembrane proteoglycans implicated as coreceptors in a variety of physiological processes, including cell adhesion, migration, response to growth factors, development, and tumorigenesis. This review will describe this family of proteoglycans in terms of their structures and functions and their signaling in conjunction with integrins, and indicate areas for future research.
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Affiliation(s)
- J R Couchman
- Department of Cell Biology and Cell Adhesion and Matrix Research Center, University of Alabama at Birmingham, 35294, USA
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282
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Schmidt A, Möckel B, Eck J, Langer M, Gauert M, Zinke H. Cytotoxic activity of recombinant bFGF-rViscumin fusion proteins. Biochem Biophys Res Commun 2000; 277:499-506. [PMID: 11032750 DOI: 10.1006/bbrc.2000.3697] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A fusion protein (bFGF-rMLA), containing the mitogen basic fibroblast growth factor (bFGF) and the cytotoxic component of rViscumin (recombinant mistletoe lectin), the enzymatic A-chain (rMLA), was expressed in Escherichia coli, purified, and functionally characterized. bFGF-rMLA is cytotoxic for mouse B16 melanoma cells expressing the FGF receptor with an IC(50) value of approximately 1 nM. rMLA shows no significant effect on the viability of the B16 cells up to a concentration of 141 nM. Additionally, bFGF-rMLA was associated with the rViscumin B-chain (rMLB) in an in vitro folding procedure. The IC(50) value of bFGF-rMLA/rMLB to B16 cells in the presence of lactose-to block rMLB lectin activity-was 134 pM. Thus, it was possible to enhance the efficacy of a rViscumin A-chain mitotoxin through addition of rMLB. We conclude that rViscumin fusion proteins may be generally applicable for the receptor-specific inactivation of target cells and point out their potential in drug development.
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MESH Headings
- Animals
- Cell Death/drug effects
- Cloning, Molecular
- Dose-Response Relationship, Drug
- Electrophoresis, Polyacrylamide Gel
- Escherichia coli/metabolism
- Fibroblast Growth Factor 2/metabolism
- Inhibitory Concentration 50
- Kinetics
- Lectins/chemistry
- Melanoma, Experimental
- Mice
- Oligonucleotides/metabolism
- Plant Preparations
- Plant Proteins
- Plasmids/metabolism
- Protein Folding
- Protein Structure, Tertiary
- Recombinant Fusion Proteins/pharmacology
- Ribosome Inactivating Proteins, Type 2
- Time Factors
- Toxins, Biological/chemistry
- Toxins, Biological/metabolism
- Toxins, Biological/pharmacology
- Tumor Cells, Cultured
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Affiliation(s)
- A Schmidt
- BRAIN Aktiengesellschaft, Zwingenberg, 64673, Germany
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283
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Park PW, Reizes O, Bernfield M. Cell surface heparan sulfate proteoglycans: selective regulators of ligand-receptor encounters. J Biol Chem 2000; 275:29923-6. [PMID: 10931855 DOI: 10.1074/jbc.r000008200] [Citation(s) in RCA: 293] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Affiliation(s)
- P W Park
- Division of Newborn Medicine, Department of Pediatrics, Children's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA.
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284
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Perrimon N, Bernfield M. Specificities of heparan sulphate proteoglycans in developmental processes. Nature 2000; 404:725-8. [PMID: 10783877 DOI: 10.1038/35008000] [Citation(s) in RCA: 569] [Impact Index Per Article: 23.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Heparan sulphate proteoglycans are abundant cell-surface molecules that consist of a protein core to which heparan sulphate glycosaminoglycan chains are attached. The functions of these molecules have remained mostly underappreciated by developmental biologists; however, the actions of important signalling molecules, for example Wnt and Hedgehog, depend on them. To understand both the mechanisms by which ligands involved in development interact with their receptors and how morphogens pattern tissues, biologists need to consider the functions of heparan sulphate proteoglycans in signalling and developmental patterning.
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Affiliation(s)
- N Perrimon
- Department of Genetics, Howard Hughes Medical Institute, Harvard Medical School, Boston, Massachusetts 02115, USA
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