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Shatirishvili M, Burk AS, Franz CM, Pace G, Kastilan T, Breuhahn K, Hinterseer E, Dierich A, Bakiri L, Wagner EF, Ponta H, Hartmann TN, Tanaka M, Orian-Rousseau V. Epidermal-specific deletion of CD44 reveals a function in keratinocytes in response to mechanical stress. Cell Death Dis 2016; 7:e2461. [PMID: 27831556 PMCID: PMC5260879 DOI: 10.1038/cddis.2016.342] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Revised: 09/18/2016] [Accepted: 09/23/2016] [Indexed: 11/09/2022]
Abstract
CD44, a large family of transmembrane glycoproteins, plays decisive roles in physiological and pathological conditions. CD44 isoforms are involved in several signaling pathways essential for life such as growth factor-induced signaling by EGF, HGF or VEGF. CD44 is also the main hyaluronan (HA) receptor and as such is involved in HA-dependent processes. To allow a genetic dissection of CD44 functions in homeostasis and disease, we generated a Cd44 floxed allele allowing tissue- and time-specific inactivation of all CD44 isoforms in vivo. As a proof of principle, we inactivated Cd44 in the skin epidermis using the K14Cre allele. Although the skin of such Cd44Δker mutants appeared morphologically normal, epidermal stiffness was reduced, wound healing delayed and TPA induced epidermal thickening decreased. These phenotypes might be caused by cell autonomous defects in differentiation and HA production as well as impaired adhesion and migration on HA by Cd44Δker keratinocytes. These findings support the usefulness of the conditional Cd44 allele in unraveling essential physiological and pathological functions of CD44 isoforms.
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Affiliation(s)
- M Shatirishvili
- Karlsruhe Institute of Technology, Institute of Toxicology and Genetics, Karlsruhe, Germany
| | - A S Burk
- University of Heidelberg, Institute of Physical Chemistry, Heidelberg, Germany
| | - C M Franz
- Karlsruhe Institute of Technology, DFG-Center for Functional Nanostructures, Karlsruhe, Germany
| | - G Pace
- Karlsruhe Institute of Technology, Institute of Toxicology and Genetics, Karlsruhe, Germany
| | - T Kastilan
- Karlsruhe Institute of Technology, Institute of Toxicology and Genetics, Karlsruhe, Germany
| | - K Breuhahn
- Heidelberg University Hospital, Institute of Pathology, Heidelberg, Germany
| | - E Hinterseer
- Laboratory for Immunological and Molecular Cancer Research, Third Medical Department with Hematology, Medical Oncology, Hemostaseology, Infectious Diseases, and Rheumatology, Oncologic Center, Paracelsus Medical University, Salzburg, Austria
| | - A Dierich
- Institut Clinique de la Souris Illkirch, Illkirch, France
| | - L Bakiri
- Spanish National Cancer Centre, Genes Development and Disease Group, Cancer Cell Biology Programme, Madrid, Spain
| | - E F Wagner
- Spanish National Cancer Centre, Genes Development and Disease Group, Cancer Cell Biology Programme, Madrid, Spain
| | - H Ponta
- Karlsruhe Institute of Technology, Institute of Toxicology and Genetics, Karlsruhe, Germany
| | - T N Hartmann
- Laboratory for Immunological and Molecular Cancer Research, Third Medical Department with Hematology, Medical Oncology, Hemostaseology, Infectious Diseases, and Rheumatology, Oncologic Center, Paracelsus Medical University, Salzburg, Austria
| | - M Tanaka
- University of Heidelberg, Institute of Physical Chemistry, Heidelberg, Germany.,Institute for Integrated Cell-Material Sciences (WPI iCeMS), Kyoto University, Kyoto 606-8501, Japan
| | - V Orian-Rousseau
- Karlsruhe Institute of Technology, Institute of Toxicology and Genetics, Karlsruhe, Germany
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2
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Abstract
CD44 is a family of single-span transmembrane glycoproteins. Members of this family differ in the extracellular domain where ten variant exons are either excluded or included in various combinations. CD44 isoforms participate in many physiological processes including hematopoiesis, regeneration, lymphocyte homing and inflammation. Most importantly, they are involved in pathological processes and in particular in cancer. In several types of tumors, CD44 together with other antigens specifies for cancer stem cell populations. Mechanistically, CD44 proteins act as receptors for hyaluronan, co-receptor for receptor tyrosine kinases (RTKs) or G-protein-coupled receptors or provide a platform for metalloproteinases. For all these reasons, targeting CD44 may be a successful approach in cancer therapy. In this review, we discuss the various possibilities of targeting CD44. Among these are the production of CD44 ectodomains, antibodies, peptides or aptamers. Also inhibition of CD44 expression has been proposed. Finally, the function of CD44 as a hyaluronan receptor was also taken advantage of. We are convinced that the success of these therapies will depend on an increased understanding of the molecular functions of specific CD44 isoforms in particular in cancer stem cells.
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Affiliation(s)
- V Orian-Rousseau
- Institute of Toxicology and Genetics, Karlsruhe Institute of Technology, Postfach 3640, 76021, Karlsruhe, Germany,
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Sleeman J, Moll J, Sherman L, Dall P, Pals ST, Ponta H, Herrlich P. The role of CD44 splice variants in human metastatic cancer. Ciba Found Symp 2007; 189:142-51; discussion 151-6, 174-6. [PMID: 7587629 DOI: 10.1002/9780470514719.ch11] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The large family of CD44 splice variants are likely to serve multiple functions in the embryo and in the adult organism. This is reflected in their complex patterns of expression. In molecular terms these functions are largely unknown. Certain splice variants (CD44v) can promote the metastatic behaviour of cancer cells. In human colon and breast cancer the presence of epitopes encoded by exon v6 on primary resected tumour material indicates poor prognosis. Metastasis-promoting splice variants differ from those that seem not to have a role in the induction of metastasis by the formation of homomultimeric complexes in the plasma membrane of cells. This may increase their affinity to ligands such as hyaluronate. The affinity can be further regulated over a range from low to very high by cell-specific modification. The fact that CD44v epitopes are found on normal epithelial cells such as skin, cervical epithelium and bladder enforces cautious evaluation of the significance of CD44v expression in human cancer. Nevertheless, certain epitopes can serve as tools in early diagnosis of certain cancers and will facilitate the development of specific targeted therapy.
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Affiliation(s)
- J Sleeman
- Kernforschungszentrum Karlsruhe, Institut für Genetik, Germany
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Affiliation(s)
- S Weg-Remers
- Forschungszentrum Karlsruhe, Germany, Institute of Toxicology and Genetics, 76021 Karlsruhe, Germany.
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Ahrens T, Sleeman JP, Schempp CM, Howells N, Hofmann M, Ponta H, Herrlich P, Simon JC. Soluble CD44 inhibits melanoma tumor growth by blocking cell surface CD44 binding to hyaluronic acid. Oncogene 2001; 20:3399-408. [PMID: 11423990 DOI: 10.1038/sj.onc.1204435] [Citation(s) in RCA: 140] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2001] [Revised: 02/07/2001] [Accepted: 03/06/2001] [Indexed: 01/11/2023]
Abstract
Proteolytic cleavage of the extracellular domain of CD44 from the surface of cells has been observed recently in different cell types. In cell culture supernatants of human melanoma cell lines a 70 kDa soluble CD44 protein (solCD44) was detected at concentrations of 250-300 ng/ml. Protease inhibitor studies revealed that serine proteases and metalloproteases are involved in the cleavage of CD44 from the surface of melanoma cells. To analyse a possible function of soluble CD44 a human malignant melanoma cell line was stably transfected with cDNAs encoding either wild type soluble CD44s or mutated forms with defective HA binding properties (CD44sR41A and CD44sR150A/R154A). Soluble CD44s almost completely inhibited hyaluronic acid binding by melanoma cells, whereas soluble CD44 mutated in the HA binding domain had no effect. When cultivated on hyaluronic acid, melanoma cell proliferation was induced by 30% for both the parental and the control transfected cells. This increase in proliferation was blocked completely in solCD44s-secreting transfectants, whereas solCD44sR41A and solCD44sR150A/R154A-secreting cells again showed hyaluronic acid-induced cell proliferation. These cell lines were subcutaneously injected into MF1 nu/nu mice to compare their growth as tumors in vivo. Compared to tumors derived from parental and control transfected cells, we observed a dramatic reduction of primary tumor growth with solCD44s expressing MM cells. Transfectants expressing solCD44s mutated in the HA binding domain in contrast developed fast-growing primary tumors. These results provide strong evidence that direct solCD44 interactions with hyaluronic acid interfere competitively with processes induced by hyaluronic acid binding to surface CD44. Autocrine, or drug-induced secretion of solCD44 by human melanoma cells may thus exert potent antitumoral effects in vivo.
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Affiliation(s)
- T Ahrens
- Department of Dermatology, University of Freiburg, Hauptstrasse 7, D-79104, Freiburg, Germany
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Morrison H, Sherman LS, Legg J, Banine F, Isacke C, Haipek CA, Gutmann DH, Ponta H, Herrlich P. The NF2 tumor suppressor gene product, merlin, mediates contact inhibition of growth through interactions with CD44. Genes Dev 2001; 15:968-80. [PMID: 11316791 PMCID: PMC312675 DOI: 10.1101/gad.189601] [Citation(s) in RCA: 383] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The neurofibromatosis-2 (NF2) gene encodes merlin, an ezrin-radixin-moesin-(ERM)-related protein that functions as a tumor suppressor. We found that merlin mediates contact inhibition of growth through signals from the extracellular matrix. At high cell density, merlin becomes hypo-phosphorylated and inhibits cell growth in response to hyaluronate (HA), a mucopolysaccharide that surrounds cells. Merlin's growth-inhibitory activity depends on specific interaction with the cytoplasmic tail of CD44, a transmembrane HA receptor. At low cell density, merlin is phosphorylated, growth permissive, and exists in a complex with ezrin, moesin, and CD44. These data indicate that merlin and CD44 form a molecular switch that specifies cell growth arrest or proliferation.
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Affiliation(s)
- H Morrison
- Forschungszentrum Karlsruhe, Institute of Toxicology and Genetics, and University of Karlsruhe, Institute of Genetics, 76021 Karlsruhe, Germany
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Matter N, Marx M, Weg-Remers S, Ponta H, Herrlich P, König H. Heterogeneous ribonucleoprotein A1 is part of an exon-specific splice-silencing complex controlled by oncogenic signaling pathways. J Biol Chem 2000; 275:35353-60. [PMID: 10958793 DOI: 10.1074/jbc.m004692200] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Regulation of alternative pre-mRNA splicing, recognized as increasingly important in causing human disease, was studied using the CD44 gene, whose splice variants have been implicated in tumor progression. We identified heterogeneous ribonucleoprotein (hnRNP) A1 as a protein interacting in vitro and in vivo with regulatory splice elements in CD44 variant exon v5. Transient overexpression of hnRNP A1 prevented v5 exon inclusion, dependent on the exonic elements. HnRNP A1-dependent repression was exon-specific and could be relieved by coexpression of oncogenic forms of Ras and Cdc42. The results define hnRNP A1 as a decisive part of an oncogene-regulated splice-silencing complex, which can select between multiple alternatively spliced exons.
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Affiliation(s)
- N Matter
- Forschungszentrum Karlsruhe, Institut für Toxikologie und Genetik, and Universität Karlsruhe, Institut für Genetik, Postfach 3640, 76021 Karlsruhe, Germany
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Hebbard L, Steffen A, Zawadzki V, Fieber C, Howells N, Moll J, Ponta H, Hofmann M, Sleeman J. CD44 expression and regulation during mammary gland development and function. J Cell Sci 2000; 113 ( Pt 14):2619-30. [PMID: 10862719 DOI: 10.1242/jcs.113.14.2619] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
The CD44v6 epitope has been widely reported to be expressed in human mammary carcinomas, yet its prognostic significance is controversial and its function in mammary tumors and mammary glands is unknown. To begin to resolve these issues, we analysed in detail the normal postnatal expression patterns and regulation of the CD44v6 epitope in murine mammary glands. We demonstrate that significant CD44v6 epitope expression is first seen during puberty, and that after puberty CD44v6 epitope expression follows the estrous cycle. CD44v6 epitope expression is observed in the myoepithelium and also less widely in luminal epithelial cells. During lactation, CD44v6 epitope expression is turned off and reappears during involution. The CD44 variant isoform bearing the v6 epitope is CD44v1-v10. Using HC11, a mammary epithelial cell line with stem cell characteristics, and facilitated by the cloning of the murine CD44 promoter, we show that growth factors and hormones which regulate ductal growth and differentiation modulate CD44 transcription. Together our data suggest that the CD44v6 epitope is expressed in mammary epithelial stems cells and in lineages derived from these cells, and that CD44v6 expression is regulated in part by hormones and growth factors such as IGF-1 and EGF which regulate the growth and differentiation of the mammary epithelium. The function of these same growth factors and hormones is often perturbed in mammary carcinomas, and we suggest that CD44v6 expression in tumors reflects this perturbation. We conclude that the expression of the CD44v6 epitope observed in some mammary tumors reflects the stem cell origin of breast tumors, and that whether or not the CD44v6 epitope is expressed in a mammary tumor is determined by the differentiation status of the tumor cells.
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Affiliation(s)
- L Hebbard
- Forschungszentrum Karlsruhe, Institute für Toxikologie und Genetik, Postfach 3640, D-76021 Karlsruhe, Germany
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Herrlich P, Morrison H, Sleeman J, Orian-Rousseau V, König H, Weg-Remers S, Ponta H. CD44 acts both as a growth- and invasiveness-promoting molecule and as a tumor-suppressing cofactor. Ann N Y Acad Sci 2000; 910:106-18; discussion 118-20. [PMID: 10911909 DOI: 10.1111/j.1749-6632.2000.tb06704.x] [Citation(s) in RCA: 109] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
High-molecular-weight splice variants of the CD44 transmembrane protein family have been implicated in tumorigenesis and metastasis formation. By contrast, in certain tumors--for example, Burkitt's lymphoma, neuroblastomas, and prostate cancer--loss of CD44 expression seems to accompany transformation. Here we describe two modes of action of CD44 proteins. They can bind growth factors and present them to their authentic high-affinity receptors, and thus promote proliferation and invasiveness of cells. Under these conditions the CD44 proteins recruit ERM proteins--for example, ezrin or moesin--to their cytoplasmic tails, thereby producing links to the cytoskeleton. This mode of action could account for the tumor-promoting action of CD44 proteins. The second mode of action of CD44 proteins comes into play when cells reach confluent growth conditions. Under specific conditions, binding of another ligand, the ECM component hyaluronate, leads to the activation and binding to the CD44 cytoplasmic tail of the tumor suppressor protein merlin. The activation of merlin confers growth arrest, so-called contact inhibition. This function of CD44 proteins defines them as tumor suppressors. The type of action of CD44 on a given cell will depend on the isoform pattern of CD44 expressed, on the cellular equipment with ERM protein members, on the nature of the ECM, and on yet-unknown conditions.
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Affiliation(s)
- P Herrlich
- Forschungszentrum Karlsruhe, Institut für Toxikologie und Genetik, Germany.
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10
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Sleeman JP, Kim U, LePendu J, Howells N, Coquerelle T, Ponta H, Herrlich P. Inhibition of MT-450 rat mammary tumour growth by antibodies recognising subtypes of blood group antigen B. Oncogene 1999; 18:4485-94. [PMID: 10442639 DOI: 10.1038/sj.onc.1202808] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Using subtractive immunization to identify cell surface epitopes expressed in a metastasis-specific fashion on cells of the rat MT-W9 mammary carcinoma model, we generated a monoclonal antibody called M-N#1. This antibody binds specifically to metastasizing cells of the MT-W9 series and also to certain other metastasizing rat mammary carcinoma cell lines. We demonstrate that the M-N#1 antibody recognizes a fucosylated N-glycosyl sugar modification, and furthermore show that the epitope specificity of the M-N#1 antibody is for blood group antigen B subtypes 2, 3 and 4 with slight cross-reactivity with blood group antigen A subtype 2. The expression of these carbohydrate epitopes on MT-450 cells is functionally important, because the M-N#1 antibody efficiently inhibits MT-450 tumour growth in spontaneous metastasis assays. These results suggest that expression of the subtypes of blood group antigen B recognized by the M-N#1 antibody does not directly participate in the metastatic cascade but rather confers a growth or survival advantage on the tumour cells.
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Affiliation(s)
- J P Sleeman
- Forschungszentrum Karlsruhe, Institute of Genetics, Germany
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11
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Khaldoyanidi S, Moll J, Karakhanova S, Herrlich P, Ponta H. Hyaluronate-enhanced hematopoiesis: two different receptors trigger the release of interleukin-1beta and interleukin-6 from bone marrow macrophages. Blood 1999; 94:940-9. [PMID: 10419885] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023] Open
Abstract
The glycosaminoglycan hyaluronate (HA) is part of the extracellular environment in bone marrow. We show here that HA activates signal transduction cascades important for hemopoiesis. In myeloid and lymphoid long-term bone marrow cultures (LTBMC), treatment with hyaluronidase (HA'ase) results in reduced production of both progenitor and mature cells. Exogeneous HA added to LTBMC had the opposite effect: it enhanced hematopoiesis. The effect of HA is mediated through two different HA receptors on bone marrow macrophage-like cells, one of which is CD44 while the other is unknown. HA induces bone marrow macrophages to secrete IL-1beta (CD44-dependent) and IL-6 (CD44-independent). The two receptors address different signal transduction pathways: CD44 links to a pathway activating p38 protein kinase while the other yet unknown receptor induces Erk activity. There was no difference of the effect of HA and HA'ase on hematopoiesis in LTBMC and on cytokine production by macrophages in CD44-deficient mice compared with wild-type mice, indicating that the CD44 hyaluronate receptor and its signal transduction can be compensated for. Our data suggest a regulatory role for the extracellular matrix component HA in hematopoiesis and show the induction of signal transduction by HA receptors.
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Affiliation(s)
- S Khaldoyanidi
- Forschungszentrum Karlsruhe, Institute of Genetics, Karlsruhe, Germany
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Foekens JA, Dall P, Klijn JG, Skroch-Angel P, Claassen CJ, Look MP, Ponta H, Van Putten WL, Herrlich P, Henzen-Logmans SC. Prognostic value of CD44 variant expression in primary breast cancer. Int J Cancer 1999; 84:209-15. [PMID: 10371335 DOI: 10.1002/(sici)1097-0215(19990621)84:3<209::aid-ijc2>3.0.co;2-9] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
CD44 is a family of cell surface transmembrane glycoproteins members which differ in the extracellular part by sequences derived by alternative splicing of 10 variant exons (v1-v10). CD44 proteins containing such variant sequences have been implicated in tumor metastasis formation. Here, we have evaluated the expression of CD44 variants by immuno-histochemistry in primary breast cancer samples of 237 node-negative and 230 node-positive patients. For the analysis of samples derived from node-negative patients, the exon-specific antibodies used were DIII, vff7 and vff18 (v6), vff17 (v7/v8), fw11.24 (v9) and vff16 (v10). With the different antibodies which recognize v6 epitopes, the majority of tumors were positively stained (> or = 65% of the tumors) with varying intensities. Thirty-nine percent of the tumors were positively stained with the antibody vff16, and approximately half of the tumors with the antibodies vff17 and fw11.24. The expression of CD44 v6 epitopes in tumors from node-negative patients was associated with a favorable prognosis, both upon univariate and multivariate analysis. The expression of CD44 v7/8, v9 or v10 epitopes was not significantly related with relapse-free survival. Samples from node-positive patients were only examined with the antibodies vff7, vff17 and vff18. The staining with none of these antibodies was correlated with the length of relapse-free survival of the patients. Our data suggest that, generally, the usefulness of knowledge of CD44 variant expression is of limited value for assessing the risk of relapse in patients with primary breast cancer. However, the expression of exon v6 of CD44 may be a marker to identify patients with a relatively favorable prognosis in node-negative patients.
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Affiliation(s)
- J A Foekens
- Department of Medical Oncology, Rotterdam Cancer Institute (Daniel den Hoed Kliniek)/Academic Hospital, The Netherlands.
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Abstract
We have recently shown that the published cDNA sequence encoding the murine cell surface receptor for hyaluronan-mediated motility (RHAMM) in fact represents a partial sequence of the cDNA encoding a new intracellular hyaluronic acid binding protein (IHABP). Here we publish the genomic organisation, including 700bp sequences of the promoter region, of the IHABP gene. The IHABP gene consists of 18 exons and spans more than 25kb. Part of the IHABP gene is identical with the published data on RHAMM. The IHABP gene apparently possesses one promoter region with one major transcriptional start point. IHABP is ubiquitously expressed at the mRNA and the protein level in all murine tissues, suggesting that the function of this intracellular hyaluronan binding protein is not restricted to migrating cells.
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Affiliation(s)
- C Fieber
- Forschungszentrum Karlsruhe, Institute of Genetics, D-76021, Karlsruhe, Germany
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14
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Abstract
Upon allogeneic transplantation (Tx) of pancreatic islets under the kidney capsule of diabetic rats, cells from draining lymph nodes and, to a minor degree, bone marrow transiently upregulate CD44 splice variants as detected by RT-PCR using CD44 variant exon specific primers. Maximal expression was on day 5 post Tx in lymph nodes and thus precedes islet rejection sufficiently (in this model by 5 days) to still permit establishing rescue by immunosuppressive therapy. CD44 variant exon sequence could therefore serve as early markers of allograft rejection.
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Affiliation(s)
- K F Milde
- Forschungszentrum Karlsruhe, Institute of Genetics, Germany
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Hofmann M, Assmann V, Fieber C, Sleeman JP, Moll J, Ponta H, Hart IR, Herrlich P. Problems with RHAMM: a new link between surface adhesion and oncogenesis? Cell 1998; 95:591-2; author reply 592-3. [PMID: 9845361 DOI: 10.1016/s0092-8674(00)81628-1] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Affiliation(s)
- M Hofmann
- Forschungszentrum Karlsruhe and University of Karlsruhe, Institutes of Genetics, Germany
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16
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Abstract
A variant of CD44 containing exon v3 sequences is expressed in the apical ectodermal ridge of the limb bud during embryogenesis. This variant is modified by heparan sulfate moieties and acts as low affinity receptor for FGFs. These FGFs are presented by CD44 to mesenchymal cells which induces their proliferation and limb outgrowth. We suggest that a similar growthfactor presentation mechanism accounts for the function of CD44 variants on metastasizing tumor cells.
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Affiliation(s)
- P Herrlich
- Forschungszentrum Karlsruhe, Institut für Genetik, Karlsruhe, Germany.
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17
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Weiss JM, Renkl AC, Sleeman J, Dittmar H, Termeer CC, Taxis S, Howells N, Schöpf E, Ponta H, Herrlich P, Simon JC. CD44 variant isoforms are essential for the function of epidermal Langerhans cells and dendritic cells. Cell Adhes Commun 1998; 6:157-60. [PMID: 9823467 DOI: 10.3109/15419069809004472] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Upon antigen encounter epidermal Langerhans cells (LC) and dendritic cells (DC) emigrate from peripheral organs and invade lymph nodes through the afferent lymphatic vessels and then assemble in the paracortical T cell zone and present antigen to T lymphocytes. Part of this process is mimicked by metastasizing tumor cells. Since splice variants of CD44 promote metastasis to lymph nodes we explored the expression of CD44 proteins on migrating LC and DC. We show that following antigen contact, LC and DC upregulate pan CD44 epitopes and epitopes encoded by variant exons v4, v5, v6 and v9. Antibodies against CD44 epitopes arrest LC in the epidermis, prevent the binding of activated LC and DC to the T cell zones of lymph nodes, and severely inhibit their capacity to induce a delayed type hypersensitivity reaction to a skin hapten in vivo. Our results demonstrate that CD44 splice variant expression is obligatory for the migration and function of LC and DC.
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Affiliation(s)
- J M Weiss
- Department of Dermatology, University of Freiburg, Germany.
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18
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Moll J, Khaldoyanidi S, Sleeman JP, Achtnich M, Preuss I, Ponta H, Herrlich P. Two different functions for CD44 proteins in human myelopoiesis. J Clin Invest 1998; 102:1024-34. [PMID: 9727071 PMCID: PMC508968 DOI: 10.1172/jci2494] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
CD44 is important during myelopoiesis, although the contributions of variant CD44 proteins are unclear. We show here that in human long-term bone marrow culture antibodies recognizing a CD44 NH2-terminal epitope (mab 25-32) or a CD44v6 epitope (mab VFF18) inhibit myelopoiesis. However, mab 25-32 but not mab VFF18 affects myeloid colony formation. These data suggest that an early precursor cell compartment is the target for the 25-32 antibody, whereas the mab VFF18 targets later stages in myelopoiesis. Since the bulk of hemopoietic precursor cells are negative for the v6 epitope and only a minor subset of myeloid cells express the v6 epitope, we have used several human myeloid progenitor cell lines to unravel the function of different CD44 proteins. These cell lines produce variant CD44 proteins, predominantly a new variant CD44v4-v10, when stimulated towards myeloid differentiation. Features that can be acquired by the expression of CD44v4-v10 are an increased hyaluronate (HA) and a de novo chondroitin sulphate A (CS-A) binding. Although, the expression of CD44v4-v10 per se is necessary for HA and CS-A binding, the protein backbone seems to require appropriate glycosylation. HA binding results in CD44-mediated cellular self-aggregation and adhesion to the stromal cell line MS-5. In summary, our data suggest that different CD44 proteins are important for at least two different steps in myelopoiesis.
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Affiliation(s)
- J Moll
- Forschungszentrum Karlsruhe, Institut für Genetik, P.O. Box 3640, D-76021 Karlsruhe, Germany.
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Weiss JM, Renkl AC, Ahrens T, Moll J, Mai BH, Denfeld RW, Schöpf E, Ponta H, Herrlich P, Simon JC. Activation-dependent modulation of hyaluronate-receptor expression and of hyaluronate-avidity by human monocytes. J Invest Dermatol 1998; 111:227-32. [PMID: 9699722 DOI: 10.1046/j.1523-1747.1998.00286.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
During inflammation, activated monocytes (Mo) migrate into tissues where they interact with extracellular matrix components such as hyaluronate (HA), produced in high amounts at inflammatory sites. We determined whether Mo that had invaded sites of cutaneous inflammation bind HA and express the putative HA receptors CD44 isoforms, ICAM-1, or receptor for hyaluronate-mediated motility (RHAMM). In cutaneous inflammation, activated infiltrating Mo displayed high HA avidity and expressed epitopes encoded by CD44s, CD44 variant exons v3, v4, v5, v6, v7, and v9, and ICAM-1, but not RHAMM. We further investigated how activation affects the avidity of Mo for HA and which receptors were responsible for such binding. Mo freshly purified from human peripheral blood bound little HA and expressed CD44s but no epitopes encoded by CD44v exons, ICAM-1, or RHAMM. During short-term tissue culture, Mo upregulated their HA avidity and expression of ICAM-1, CD44s, and epitopes encoded by CD44v, all of which were further augmented by IFN-gamma or lipopolysaccharide, whereas RHAMM was not detectable. Thus in vitro activated Mo resembled Mo that had migrated to inflammatory sites in vivo. Lipolysaccharide or IFN-gamma-induced HA binding was inhibited by more than 90% with monoclonal antibodies directed against N-terminal HA binding domains of CD44s, but not by monoclonal antibodies against CD44v epitopes or ICAM-1. In conclusion, we show that upon in vitro or in vivo activation, Mo enhance their capacity to bind HA. This is critically dependent upon the expression ofCD44s epitopes. Regulated CD44-HA interactions may be important for the ability of Mo to migrate into and within sites of inflammation and for Mo effector functions.
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Affiliation(s)
- J M Weiss
- Department of Dermatology, University of Freiburg, Germany
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20
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Abstract
Functional differences between members of the CD44 family of cell surface glycoproteins is mediated in part by differential post-translational modification of these proteins and by alternative splicing. Tyrosine sulphation is a secondary modification of the primary amino acid structure of a number of secreted, transmembrane and lysosomal proteins, which is associated with promotion of protein-protein interactions. Here we identify a cannonical tyrosine-sulphation motif within rat and mouse CD44 exon v5. We show that inorganic sulphate is incorporated into the metastasis-associated rat CD44v4-v7 splice variant. The sulphate is not incorporated into sulphated glycosaminoglycan or other sugar modifications of CD44v4-v7. A point mutation of the exon v5 tyrosine to phenylalanine destroys inorganic sulphate incorporation into CD44v4-v7. These results demonstrate that the tyrosine-sulphation motif within rat CD44 exon v5 is used in vivo, and suggest that exon v5 may be involved in mediating CD44 ligand binding-activity by means of its sulphated tyrosine.
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Affiliation(s)
- J P Sleeman
- Forschungszentrum Karlsruhe, Institute of Genetics, Germany.
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21
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Hofmann M, Fieber C, Assmann V, Göttlicher M, Sleeman J, Plug R, Howells N, von Stein O, Ponta H, Herrlich P. Identification of IHABP, a 95 kDa intracellular hyaluronate binding protein. J Cell Sci 1998; 111 ( Pt 12):1673-84. [PMID: 9601097 DOI: 10.1242/jcs.111.12.1673] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The extracellular matrix component hyaluronan is believed to play important roles in various processes of organogenesis, cell migration and cancer. Recognition of and binding to hyaluronan is mediated by cell surface receptors. Three of them, CD44, ICAM-1 and RHAMM (receptor for hyaluronic acid mediated motility), have been identified. A cDNA clone designated RHAMM turned out to possess transforming capacity. Based on this published sequence, we isolated the complete cDNA of the murine gene. The cDNA comprises an open reading frame of 2.3 kb and encodes a 95 kDa protein. The protein carries a hyaluronan binding motif which binds to hyaluronan in vitro but not to heparin or chondroitin sulphate. It is ubiquitously expressed in normal cells and in all tumour cell lines irrespective of their metastatic properties. One tumour cell line, the metastatic Lewis lung carcinoma, expresses a larger 105 kDa variant form of the protein due to a genomic rearrangement. Antibodies raised against the 95 kDa protein were used for subcellular localization studies. The hyaluronan binding protein is not detectable at the cell surface but is rather localized exclusively intracellularly. Clearly, the sequence we have identified encodes a protein with properties substantially different to the RHAMM protein. We tentatively name the protein intracellular hyaluronic acid binding protein, IHABP.
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Affiliation(s)
- M Hofmann
- Forschungszentrum Karlsruhe, Institute of Genetics, D-76021 Karlsruhe, Germany.
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22
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Abstract
Alternative splicing of pre-mRNA is a fundamental mechanism of differential gene expression in that it can give rise to functionally distinct proteins from a single gene, according to the developmental or physiological state of cells in multicellular organisms. In the pre-mRNA of the cell surface molecule CD44, the inclusion of up to 10 variant exons (v1-v10) is regulated during development, upon activation of lymphocytes and dendritic cells, and during tumour progression. Using minigene constructs containing CD44 exon v5, we have discovered exonic RNA elements that couple signal transduction to alternative splicing. They form a composite splice regulator encompassing an exon recognition element and splice silencer elements. Both type of elements are necessary to govern cell type-specific inclusion of the exon as well as inducible inclusion in T cells after stimulation by concanavalin A, by Ras signalling or after activation of protein kinase C by phorbol ester. Inducible splicing does not depend on de novo protein synthesis. The coupling of signal transduction to alternative splicing by such elements probably represents the mechanism whereby splice patterns of genes are established during development and can be changed under physiological and pathological conditions.
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Affiliation(s)
- H König
- Forschungzentrum Karlsruhe, Institut für Genetik, Karlsruhe, Germany
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23
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Sherman L, Wainwright D, Ponta H, Herrlich P. A splice variant of CD44 expressed in the apical ectodermal ridge presents fibroblast growth factors to limb mesenchyme and is required for limb outgrowth. Genes Dev 1998; 12:1058-71. [PMID: 9531542 PMCID: PMC316674 DOI: 10.1101/gad.12.7.1058] [Citation(s) in RCA: 129] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Signals from the apical ectodermal ridge (AER) of the developing vertebrate limb, including fibroblast growth factor-8 (FGF-8), can maintain limb mesenchymal cells in a proliferative state. We report here that a specific CD44 splice variant is crucial for the proliferation of these mesenchymal cells. Epitopes carried by this variant colocalize temporally and spatially with FGF-8 in the AER throughout early limb development. A splice variant containing the same sequences expressed on model cells binds both FGF-4 and FGF-8 and stimulates mesenchymal cells in vitro. When applied to the AER, an antibody against a specific CD44 epitope blocks FGF presentation and inhibits limb outgrowth. Therefore, CD44 is necessary for limb development and functions in a novel growth factor presentation mechanism likely relevant in other physiological and pathological situations where a cell surface protein presents a signaling molecule to a neighboring cell.
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Affiliation(s)
- L Sherman
- Forschungszentrum Karlsruhe, Institut für Genetik, D-76021 Karlsruhe, Germany
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24
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Abstract
The designation CD44 describes a group of type I transmembrane proteins which share N-terminal and C-terminal sequences. These molecules differ in the central extracellular domain by the use of sequences encoded by ten variant exons which may be completely absent or included in various combinations and by cell type specific addition of glycosaminoglycan and carbohydrate moieties. Expression of variant proteins is observed in normal tissues such as on keratinocytes, dendritic cells and activated lymphocytes in the adult organism and on morphogenetically active epithelium such as the apical ectodermal ridge (AER) in the embryo. Certain CD44 proteins expressed on the AER can act as low affinity fibroblast growth factor receptors and are vital for epithelial-mesenchymal cell communication. CD44 variant proteins have also been implicated in tumour growth and metastasis and we speculate that CD44 mediated growth factor presentation may also be decisive in metastasis formation. Molecular strategies designed to block growth factor presentation by CD44 may aid in the therapy of metastatic cancer.
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Affiliation(s)
- H Ponta
- Forschungszentrum Karlsruhe, Institute of Genetics, University of Karlsruhe, Germany
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25
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Sleeman JP, Kondo K, Moll J, Ponta H, Herrlich P. Variant exons v6 and v7 together expand the repertoire of glycosaminoglycans bound by CD44. J Biol Chem 1997; 272:31837-44. [PMID: 9395530 DOI: 10.1074/jbc.272.50.31837] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Isoforms of the glycoprotein CD44 are cell surface receptors for the glycosaminoglycan hyaluronate. They have been implicated in many biological processes, but their function in these is poorly understood and cannot be explained solely by hyaluronate binding. In the present work we examine the ligand binding properties of alternatively spliced CD44 variant isoforms which are functionally involved in the immune system, embryonic development, and tumor behavior. We show that these isoforms bind directly to the purified glycosaminoglycans chondroitin sulfate, heparin, and heparin sulfate, in addition to being able to bind to hyaluronate. Binding to this extended repertoire of glycosaminoglycans by CD44 depends on the inclusion of peptide sequences encoded by the alternatively spliced exons v6 and v7, and occurs both when the CD44 is solubilized from the plasma membrane and when it is expressed on intact cells. A single point mutation in the most N-terminal hyaluronate binding motif of CD44 ablates both hyaluronate and chondroitin sulfate binding, suggesting that glycosaminoglycans are bound through a common motif, and that only one of the hyaluronate binding motifs is responsible for the majority of glycosaminoglycan binding by CD44 on the cell surface. Taken together, these observations indicate that alternative splicing regulates the ligand binding specificity of CD44 and suggest that structural changes in the CD44 protein have a profound effect on the range of ligands to which this molecule can bind with potentially wide-ranging functional consequences.
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Affiliation(s)
- J P Sleeman
- Forschungszentrum Karlsruhe, Institute of Genetics, P. O. Box 3640, D-76021 Karlsruhe, Germany
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26
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Sherman L, Xu HM, Geist RT, Saporito-Irwin S, Howells N, Ponta H, Herrlich P, Gutmann DH. Interdomain binding mediates tumor growth suppression by the NF2 gene product. Oncogene 1997; 15:2505-9. [PMID: 9395247 DOI: 10.1038/sj.onc.1201418] [Citation(s) in RCA: 174] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The neurofibromatosis 2 (NF2) tumor suppressor gene encodes an intracellular membrane-associated protein, called merlin (or schwannomin), that belongs to the band 4.1 family of cytoskeleton-associated proteins. Inactivating NF2 mutations occur in several sporadic tumor types and have been linked to the NF2 disease, whose hallmark is the development of bilateral Schwann cell tumors (schwannomas) of the eighth cranial nerve. Two major alternatively spliced NF2 variants are expressed in normal tissues: 'NF2-17' lacking exon 16 and 'NF2-16' that contains exon 16 and encodes a merlin protein truncated at the C-terminus. We report that overexpression of NF2-17 in rat schwannoma cells inhibits their growth in vitro and in vivo, while NF2-16 fails to influence schwannoma growth. Tumor growth inhibition by merlin depends on an interdomain association occurring either in cis or in trans between the N- and C-termini. This association does not occur in the truncated NF2-16 protein nor in a mutant NF2-17 protein lacking C-terminal sequences. These data indicate that merlin has a unique mechanism of tumor suppression, inhibiting cell proliferation via self-association.
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Affiliation(s)
- L Sherman
- Forschungszentrum Karlsruhe, Institut für Genetik, Germany
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27
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Sherman L, Jacoby LB, Lampe J, Pelton P, Aguzzi A, Herrlich P, Ponta H. CD44 expression is aberrant in benign Schwann cell tumors possessing mutations in the neurofibromatosis type 2, but not type 1, gene. Cancer Res 1997; 57:4889-97. [PMID: 9354454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Atypical expression of CD44 splice variants has been implicated in the progression of numerous tumors. This abnormal CD44 expression is presumed to result from gene alterations that cause tumorigenic transformation. Two tumor types that have been linked to specific gene alterations are schwannomas, which have mutations in the neurofibromatosis (NF) type 2 (NF2) gene, and neurofibromas, which characteristically possess NF type 1 (NF1) gene mutations. We examined CD44 expression in normal sciatic nerves, in schwannomas with confirmed NF2 mutations, and in neurofibromas and malignant peripheral nerve sheath tumor tissue and cell lines from NF1 patients. Compared to normal nerves, schwannomas express higher total levels of CD44 and additional splice variants, whereas CD44 expression in neurofibromas is unaltered. Malignant peripheral nerve sheath tumor tissue and cell lines express the CD44v6 epitope, which is not expressed by normal Schwann cells or by other Schwann cell tumors. These data indicate that altered CD44 expression correlates strictly with mutations in the NF2 but not NF1 gene and suggest that CD44v6 might be a marker for the malignant transformation of Schwann cells.
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Affiliation(s)
- L Sherman
- Forschungszentrum Karlsruhe, Institut für Genetik, Karlsruhe, Germany
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28
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Dall P, Hekele A, Beckmann MW, Bender HG, Herrlich P, Ponta H. Efficient lysis of CD44v7/8-presenting target cells by genetically engineered cytotoxic T-lymphocytes--a model for immunogene therapy of cervical cancer. Gynecol Oncol 1997; 66:209-16. [PMID: 9264564 DOI: 10.1006/gyno.1997.4777] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Variant proteins of the CD44 surface glycoprotein family are expressed on many different human tumors and their lymph node metastases. An epitope encoded by sequences of variant exons CD44v7 and v8 and recognized by the monoclonal antibody VFF17 is frequently detected in cervical cancer, whereas the normal cervical epithelium lacks expression of this epitope. We have developed an immunotherapeutic approach for cervical cancer based on the expression of this CD44v7/8 epitope. The single chain antigen-binding fragment of VFF17 was fused to a signal transducing protein (zeta-chain) of the T-cell receptor complex (TCR) and was introduced into a retroviral gene transfer vector. Gene transfer was applied to the murine cytotoxic T-cell line cl96. All recombinant clones expressed the fusion protein on their cell surface. Functionality of the recombinant fusion protein was tested by subjection of several recombinant clones to in vitro cytotoxicity assays. CD44v7/8-expressing target cells were killed efficiently by reprogrammed cl96 in an MHC-independent fashion, whereas CD44v7/ 8-negative cells were not affected. These transfected T cell lines will now be tested in vivo using immune-deficient mice bearing CD44v7/8-expressing tumors.
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Affiliation(s)
- P Dall
- Department of Obstetrics and Gynecology, University Medical Center Düsseldorf, Germany
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29
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Weiss JM, Sleeman J, Renkl AC, Dittmar H, Termeer CC, Taxis S, Howells N, Hofmann M, Köhler G, Schöpf E, Ponta H, Herrlich P, Simon JC. An essential role for CD44 variant isoforms in epidermal Langerhans cell and blood dendritic cell function. J Cell Biol 1997; 137:1137-47. [PMID: 9166413 PMCID: PMC2136215 DOI: 10.1083/jcb.137.5.1137] [Citation(s) in RCA: 145] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/1997] [Revised: 03/11/1997] [Indexed: 02/04/2023] Open
Abstract
Upon antigen contact, epidermal Langerhans cells (LC) and dendritic cells (DC) leave peripheral organs and home to lymph nodes via the afferent lymphatic vessels and then assemble in the paracortical T cell zone and present antigen to T lymphocytes. Since splice variants of CD44 promote metastasis of certain tumors to lymph nodes, we explored the expression of CD44 proteins on migrating LC and DC. We show that upon antigen contact, LC and DC upregulate pan CD44 epitopes and epitopes encoded by variant exons v4, v5, v6, and v9. Antibodies against CD44 epitopes inhibit the emigration of LC from the epidermis, prevent binding of activated LC and DC to the T cell zones of lymph nodes, and severely inhibit their capacity to induce a delayed type hypersensitivity reaction to a skin hapten in vivo. Our results demonstrate that CD44 splice variant expression is obligatory for the migration and function of LC and DC.
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Affiliation(s)
- J M Weiss
- Department of Dermatology, Freiburg University, D-79104 Freiburg, Germany
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30
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Sleeman J, Rudy W, Hofmann M, Moll J, Herrlich P, Ponta H. Regulated clustering of variant CD44 proteins increases their hyaluronate binding capacity. J Biophys Biochem Cytol 1996; 135:1139-50. [PMID: 8922392 PMCID: PMC2133377 DOI: 10.1083/jcb.135.4.1139] [Citation(s) in RCA: 113] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Cell contact with the extracellular matrix component hyaluronic acid (HA) plays an important role in many developmental, physiological, and pathological processes, although the regulation of this contact is poorly understood. CD44 proteins carry an amino acid motif that mediates affinity to HA. Artificial clustering of the smallest 85-kD isoform of CD44 (CD44s) has previously been shown to promote binding of the protein to soluble HA (Lesley, J., R. Hyman, and P.W. Kincade. 1993. Adv. Immunol. 54:271-335; Persche, A., J. Lesley, N. English, I. Trowbridge, and R. Hyman. 1995. Eur. J. Immunol. 25:495-501). Here we show that in rat pancreatic carcinoma cells, splice variants of CD44 (CD44v), but not CD44s, form molecular aggregates in the plasma membrane. We demonstrate that reduction-sensitive dimerization of CD44v occurs, and also that larger aggregations of the protein can be stabilized by chemical cross-linking. Different CD44v proteins present on the same cell exclusively form homoaggregates. Molecular clustering does not require an intact cytoplasmic domain of the protein. The ability of cells to bind to soluble HA is upregulated more than one magnitude by the ectopic expression of CD44v4-v7, but only when the CD44v4-v7 protein forms intermolecular aggregates. Tunicamycin treatment inhibits HA binding by CD44v and at the same time destroys oligomerization. We propose that the regulation of clustering of CD44, mediated by factors including the presence of variant exons and glycosylation, allows cells in turn to regulate their HA binding properties.
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Affiliation(s)
- J Sleeman
- Forschungszentrum Karlsruhe, Institute of Genetics, Germany
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31
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Hekele A, Dall P, Moritz D, Wels W, Groner B, Herrlich P, Ponta H. Growth retardation of tumors by adoptive transfer of cytotoxic T lymphocytes reprogrammed by CD44v6-specific scFv:zeta-chimera. Int J Cancer 1996; 68:232-8. [PMID: 8900434 DOI: 10.1002/(sici)1097-0215(19961009)68:2<232::aid-ijc16>3.0.co;2-c] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Variants of the CD44 protein family containing sequences encoded by variant exon 6 (v6) are involved in the metastatic spread of rat and human tumors. The rat-specific antibody 1.1ASML, which recognizes a v6 epitope, interferes with metastatic dissemination of a rat pancreatic carcinoma. The single-chain antigen-binding fragment of this monoclonal antibody was fused to the zeta-chain of the T-cell receptor complex. The appropriate fusion gene was incorporated into a retroviral gene transfer vector. Murine cytotoxic T lymphocytes (CTLs) were infected, and cellular clones which express the single-chain zeta-chain fusion protein on their cell surface were selected. These CTLs are not MHC-restricted in their CD44v6 recognition and exhibit in vitro lytic activity toward cells expressing CD44 variants comprising exon v6. Tumor cell xenografts grown in athymic nude mice are suppressed in their growth upon infusion of the genetically manipulated CTLs. Our data indicate that the CD44v6 epitope is an effective target for immune tumor therapy and demonstrate the efficacy of genetically engineered CTLs in targeting tumors expressing such epitopes.
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Affiliation(s)
- A Hekele
- Research Center Karlsruhe, Institute of Genetics, Germany
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32
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33
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Konig H, Moll J, Ponta H, Herrlich P. Trans-acting factors regulate the expression of CD44 splice variants. EMBO J 1996; 15:4030-9. [PMID: 8670907 PMCID: PMC452123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Variant isoforms of the cell surface glycoprotein CD44 (CD44v) are expressed during development, in selected adult tissues and in certain metastatic tumor cells. CD44v differ from the standard isoform (CD44s) by up to ten additional exon sequences included by alternative splicing. By cell fusion experiments, we have obtained evidence for the existence of cell-type specific trans-acting factors recruiting CD44 variant exon sequences. Stable cell hybrids of CD44s and CD44v expressing cells indicated a dominant mechanism for variant-exon inclusion. In transient interspecies heterokaryons of human keratinocytes and rat fibroblasts, the ability of the keratinocytes to include all variant exon sequences in CD44 was conferred completely on the rat fibroblast nucleus. Fusions of cells with complex CD44 splice patterns do not permit interpretation of splice control by the relative abundance of a single trans-acting factor, but rather by (a) positively acting factor(s) recruiting variant exon sequences in the 3' to 5' direction and additional factors selecting individual exons. Since the pancreatic carcinoma cell line BSp73ASML (in contrast to the cervix carcinoma cell lines SiHa and ME180) could not transfer its specific splice pattern in cell fusions, we conclude that in some tumors, splicing is also controlled by mutation of cis-acting recognition sites.
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Affiliation(s)
- H Konig
- Forschungszentrum Karlsruhe der Helmholtz-Gemeinschaft, Institut für Genetik, Postfach 3640, 76021 Karlsruhe, Germany
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34
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Abstract
In animal models, isoforms of CD44 (CD44v) containing sequences encoded by one or several of ten different exons (v1-v10) contribute to tumour metastasis. In certain human cancers, CD44v6 expression is associated with poor prognosis. This paper examines CD44v expression in skin carcinogenesis and skin cancer metastasis. CD44v expression was studied in basal cell carcinoma (BCC), squamous cell carcinoma (SCC), primary malignant melanoma (PMM), metastases of MM (MMM), benign melanocytic naevi (BMN) and normal skin (NS) by immunohistochemistry and reverse transcript polymerase chain reaction (RT-PCR). BCC, SCC and NS expressed several CD44v, including v6, albeit in different distributions and intensities. PMM, MMM and BMN expressed isoforms containing v7/8 and v10, but failed to express epitopes encoded by v5 or v6. Thus, different CD44 isoforms are found in human skin cancers and are modulated during carcinogenesis. However, we did not observe a correlation of CD44v6 expression with metastatic potential.
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MESH Headings
- Antigens, Neoplasm/analysis
- Antigens, Neoplasm/genetics
- Carcinoma, Basal Cell/chemistry
- Carcinoma, Basal Cell/genetics
- Carcinoma, Squamous Cell/chemistry
- Carcinoma, Squamous Cell/genetics
- Gene Expression
- Humans
- Hyaluronan Receptors/analysis
- Hyaluronan Receptors/genetics
- Immunoenzyme Techniques
- Melanoma/chemistry
- Melanoma/genetics
- Melanoma/secondary
- Nevus, Pigmented/chemistry
- Nevus, Pigmented/genetics
- Polymerase Chain Reaction
- RNA, Messenger/genetics
- RNA, Neoplasm/genetics
- Skin/chemistry
- Skin Neoplasms/chemistry
- Skin Neoplasms/genetics
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Affiliation(s)
- J C Simon
- Department of Dermatology, University of Freiburg, Germany
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35
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Sleeman JP, Arming S, Moll JF, Hekele A, Rudy W, Sherman LS, Kreil G, Ponta H, Herrlich P. Hyaluronate-independent metastatic behavior of CD44 variant-expressing pancreatic carcinoma cells. Cancer Res 1996; 56:3134-41. [PMID: 8674073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Several studies have demonstrated a correlation between the expression of CD44 variant isoforms and the ability of tumor cells to metastasize. The CD44 proteins carry amino acid sequence motifs that confer the ability to bind to the extracellular matrix component hyaluronate (HA). In this study, we investigated whether a CD44 variant previously shown to stimulate metastasis in a rat pancreatic carcinoma model (BSp73AS) is capable of binding to HA, and whether such binding is critical for metastasis. We show that transfection of this CD44 variant into BSp73AS cells increases the HA-binding capacity of the cells in a dose-dependent manner. Transfection of the same CD44 variant isoform into BDX2 cells also conferred strong HA-binding properties on these cells, but was insufficient to cause them to metastasize. Transfection of a surface-bound hyaluronidase into metastasizing BSp73AS cells bearing variant CD44 efficiently ablated the ability of these cells to bind to HA. However, in metastasis assays, these hyaluronidase-transfected cells showed patterns of metastasis similar to those of the parental cell line. We also show that the HA-binding capacity of a variety of tumor cells is not correlated with their metastatic proclivity, and that an antibody previously shown to block metastasis of the pancreatic carcinoma cells does not interfere with their ability to bind to HA. We conclude that although CD44 variant expression does promote metastasis formation, HA binding by tumor cells is not rate limiting for metastasis in the BSp73AS system and probably also in other metastasizing tumors. Furthermore, for metastasis by CD44 variant-expressing BSp73AS cells to occur, contact of the CD44 variant protein with a ligand other than HA Is required.
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Affiliation(s)
- J P Sleeman
- Forschungszentrum Karlsruhe, Institute of Genetics, Germany
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36
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Wainwright D, Sherman L, Sleeman J, Ponta H, Herrlich P. A splice variant of CD44 expressed in the rat apical ectodermal ridge contributes to limb outgrowth. Ann N Y Acad Sci 1996; 785:345-9. [PMID: 8702177 DOI: 10.1111/j.1749-6632.1996.tb56305.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Affiliation(s)
- D Wainwright
- Institut für Genetik, Forschungszentrum Karlsruhe, Germany
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37
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Dall P, Hekele A, Ikenberg H, Göppinger A, Bauknecht T, Pfleiderer A, Moll J, Hofmann M, Ponta H, Herrlich P. Increasing incidence of CD44v7/8 epitope expression during uterine cervical carcinogenesis. Int J Cancer 1996; 69:79-85. [PMID: 8608987 DOI: 10.1002/(sici)1097-0215(19960422)69:2<79::aid-ijc2>3.0.co;2-s] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Splice variants of the cell surface glycoprotein CD44 (CD44v) have been implicated in the progression of various human tumors. In the present study, we have examined the expression pattern of a CD44v epitope encoded by the adjacent variant exons v7 and v8 during human cervical carcinogenesis. While only l/ll normal cervical squamous epithelia was positive for this epitope by immunohistochemistry, 4/21 samples of low-grade squamous intra-epithelial lesions (LSIL), 17/35 samples of high-grade squamous intra-epithelial lesions (HSIL), 11/12 samples of the HSIL subgroup of carcinomas in situ and 17/17 cases of invasive cervical carcinoma showed CD44v7/8 epitope expression. In addition to CD44 variant expression, we have analyzed 67 lesions for the presence of HPV16/18-DNA using PCR. Most of the samples expressing the v7/8 epitope were also HPV16-positive (29/32), whereas only 17/35 of the v7/8-negative samples were HPV16-positive. HPV18 DNA was found in only one invasive carcinoma. Our data suggests that high-risk HPV infection may precede CD44v7/8 expression and that the number of samples expressing the CD44v7/8 epitope increases during carcinogenesis and reaches nearly 100% at the carcinoma in situ stage. This CD44 epitope could, therefore, serve as a diagnostic marker of cervical squamous cell carcinomas and as a possible target for CD44v7/8 epitope-directed therapies.
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Affiliation(s)
- P Dall
- Institute of Genetics, Research Center Karlsruhe, Germany
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38
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Moll J, Schmidt A, van der Putten H, Plug R, Ponta H, Herrlich P, Zöller M. Accelerated immune response in transgenic mice expressing rat CD44v4-v7 on T cells. The Journal of Immunology 1996. [DOI: 10.4049/jimmunol.156.6.2085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Abstract
Splice variants of the glycoprotein CD44 (CD44v) that confer metastatic behavior to noninvasively growing rat tumor cells are transiently expressed on lymphocytes during activation. A mAb directed against an epitope encoded by CD44 exon v6 blocks both metastasis formations and lymphocyte activation, implicating CD44v in normal immune function. To explore the nature of this function of CD44v, transgenic mice were generated that constitutively express rat CD44v4-v7 on thymocytes and peripheral T cells. The number of lymphocytes as well as the distribution of lymphocyte subpopulations were similar in nontransgenic and rat CD44v4-v7 transgenic mice. T cells of the transgenic mice, however, responded faster to activating stimuli, particularly during primary stimulations with T cell mitogens and T-dependent Ags in vivo and in vitro. This accelerated response depended on the expression of the transgene product, since a rat CD44v6-specific Ab reverted the response profiles of the transgenic mice to those of nontransgenic mice. Since the transgene gained in vivo and in vitro functional activity only upon antigenic stimulation, it is likely that CD44 variant isoforms are involved in the process of signal transduction during lymphocyte activation.
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Affiliation(s)
- J Moll
- Institute of Genetics, Nuclear Research Center, Karlsruhe, Germany
| | - A Schmidt
- Institute of Genetics, Nuclear Research Center, Karlsruhe, Germany
| | - H van der Putten
- Institute of Genetics, Nuclear Research Center, Karlsruhe, Germany
| | - R Plug
- Institute of Genetics, Nuclear Research Center, Karlsruhe, Germany
| | - H Ponta
- Institute of Genetics, Nuclear Research Center, Karlsruhe, Germany
| | - P Herrlich
- Institute of Genetics, Nuclear Research Center, Karlsruhe, Germany
| | - M Zöller
- Institute of Genetics, Nuclear Research Center, Karlsruhe, Germany
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39
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Moll J, Schmidt A, van der Putten H, Plug R, Ponta H, Herrlich P, Zöller M. Accelerated immune response in transgenic mice expressing rat CD44v4-v7 on T cells. J Immunol 1996; 156:2085-94. [PMID: 8690896] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Splice variants of the glycoprotein CD44 (CD44v) that confer metastatic behavior to noninvasively growing rat tumor cells are transiently expressed on lymphocytes during activation. A mAb directed against an epitope encoded by CD44 exon v6 blocks both metastasis formations and lymphocyte activation, implicating CD44v in normal immune function. To explore the nature of this function of CD44v, transgenic mice were generated that constitutively express rat CD44v4-v7 on thymocytes and peripheral T cells. The number of lymphocytes as well as the distribution of lymphocyte subpopulations were similar in nontransgenic and rat CD44v4-v7 transgenic mice. T cells of the transgenic mice, however, responded faster to activating stimuli, particularly during primary stimulations with T cell mitogens and T-dependent Ags in vivo and in vitro. This accelerated response depended on the expression of the transgene product, since a rat CD44v6-specific Ab reverted the response profiles of the transgenic mice to those of nontransgenic mice. Since the transgene gained in vivo and in vitro functional activity only upon antigenic stimulation, it is likely that CD44 variant isoforms are involved in the process of signal transduction during lymphocyte activation.
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Affiliation(s)
- J Moll
- Institute of Genetics, Nuclear Research Center, Karlsruhe, Germany
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40
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Sherman L, Sleeman J, Dall P, Hekele A, Moll J, Ponta H, Herrlich P. The CD44 proteins in embryonic development and in cancer. Curr Top Microbiol Immunol 1996; 213 ( Pt 1):249-69. [PMID: 8814991 DOI: 10.1007/978-3-642-61107-0_15] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- L Sherman
- Forschungszentrum Karlsruhe, Intitut für Genetik, Germany
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41
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Sherman L, Skroch-Angel P, Moll J, Schwechheimer K, Ponta H, Herrlich P, Hofmann M. Schwann cell tumors express characteristic patterns of CD44 splice variants. J Neurooncol 1995; 26:171-84. [PMID: 8750183 DOI: 10.1007/bf01052620] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Members of the CD44 family of cell surface hyaluronate-binding proteins have been implicated in cell migration, cell-matrix interactions and tumor progression. To determine whether these proteins might play a role in the normal functions of Schwann cells and in their tumorigenesis, we examined the patterns of CD44 expression in Schwann cells from rat peripheral nerve, rat Schwann cell tumor lines, and human schwannomas. Normal rat spinal nerves and primary Schwann cell cultures expressed standard CD44 (CD44s) but not alternatively spliced variant isoforms. In contrast, rat Schwann cell tumor lines expressed both CD44s and a number of variants, including proteins containing sequences encoded by exon v6. Furthermore, we found that these cell lines bind hyaluronate, and that their cell surface hyaluronate binding correlates with CD44 expression. All of the human schwannomas also expressed CD44 variants, especially epitopes encoded by exon v5, the border between v7 and v8, and v9-10. These data indicate that Schwann cells normally express CD44s, that Schwann cell tumors express both CD44s and particular variants of CD44, and that CD44s and possibly variants of CD44 are involved in hyaluronate recognition by Schwann cell tumors.
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Affiliation(s)
- L Sherman
- Institut für Genetik, Kernforschungszentrum Karlsruhe, Germany
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42
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Eibl RH, Pietsch T, Moll J, Skroch-Angel P, Heider KH, von Ammon K, Wiestler OD, Ponta H, Kleihues P, Herrlich P. Expression of variant CD44 epitopes in human astrocytic brain tumors. J Neurooncol 1995; 26:165-70. [PMID: 8750182 DOI: 10.1007/bf01052619] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Expression of CD44 and of specific splice-variants of CD44 has been causally related to metastatic behaviour in a variety of carcinomas and lymphomas. To elucidate whether, in principle, similar splice-variants could be involved in glioma cell invasion we examined the expression of CD44 and its splice-variants in a series of 38 primary human brain tumors (28 astrocytomas, WHO grade I-III and 10 glioblastomas, WHO grade IV) and in cell lines derived from 9 glioblastomas. All brain tumors examined showed strong immunoreactivity for an N-terminal epitope present on all CD44 isoforms known. Using a polyclonal antiserum raised against the complete sequence encoded by variant exons v3 to v10, CD44 splice-variants could be detected irrespective of the grade of malignancy in many of the tumor samples at a low level and often restricted to only a few clustered tumor cells. Thus, the N-terminal epitope probably indicates the presence of the smallest and most ubiquitous isoform CD44s. Interestingly, all glioblastomas expressed CD44 variants whereas expression in astrocytomas WHO grade I, II, and III could only be detected in about half of the tumor samples. Using reverse transcriptase-PCR we were able to detect different CD44 splice-variants in the glioblastoma cell lines and in cultured primary astrocytic cells. Glioblastoma cells analyzed by flow cytometry showed the expected binding capacity for hyaluronic acid which could be increased twofold after pretreatment with hyaluronidase. The results presented show that there is low expression of CD44 variants in human tumors of astrocytic origin. Expression of CD44 and its splice-variants could contribute to the migration capacity of neoplastic astrocytes, and may be considered as a target for new diagnostic and therapeutic approaches in the clinical management of brain tumors.
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Affiliation(s)
- R H Eibl
- Kernforschungszentrum Karlsruhe, Institut für Genetik, Germany
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43
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44
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Abstract
Alternative splicing of ten different variant exons (v1-v10) is responsible for the creation of a large number of different CD44 surface proteins. Some of these proteins play decisive roles in the metastatic spread of rat tumours. Also in human cancers, CD44 splice variants are frequently expressed in advanced states of tumorigenesis. In breast cancer and in non-Hodgkin's lymphomas expression of exon v6 is correlated with poor prognosis of patient survival. In colorectal carcinogenesis, expression of exon v5 is an early tumour marker since it is already detectable on small dysplastic polyps (but not on normal colon epithelium). In contrast, exon v6 expression occurred with increased frequency with tumour progression, and its expression on colorectal tumours indicated reduced survival probability. Most likely, tumours carrying the CD44 v6 epitope acquire selective advantage during tumour progression and metastasis formation. This could be a proliferative advantage since mice transgenic for the CD44 isoform CD44v4-v7 on T lymphocytes show an accelerated T-dependent immune response as compared with non-transgenic siblings.
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Affiliation(s)
- P Herrlich
- Forschungszentrum Karlsruhe, Institut für Genetik, Germany
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45
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Abstract
CD44 designates a group of closely related cell-surface proteins generated by alternative splicing. We have previously shown that splice variants carrying sequences encoded by exon v6 are preferentially expressed in metastatic animal cancer cell lines and that they confer metastatic behaviour on non-metastatic animal tumour cell lines. In this study we set out to assess the expression of CD44 epitopes specific for variant exon sequences in human breast cancer and their potential for determining prognosis. We used affinity-purified polyclonal sera and four monoclonal antibodies raised against the human homologues of CD44 variant exon sequences to investigate the presence of CD44 on 100 primary invasive breast tumours, 12 local recurrences, 18 lymph node metastases, and normal tissue controls. Whereas normal mammary ductal epithelial cells and cells derived from hyperplastic lesions do not express CD44 variant exons, expression of v3, v5, and v6 epitopes was found in most tumour samples. The DIII (exon v6) epitope was present in 84% of the primary tumours and in 100% of axillary lymph node metastases and local recurrences. The presence of these CD44 epitopes is correlated with poor overall survival. 15 patients with exon-v6-negative tumours had good survival compared with 76 patients with exon-v6-positive tumours (p = 0.005; log rank test). Multivariate analysis showed that the CD44 epitope encoded by exon v6 was a good marker for prognosis independent of progesterone receptor, lymph node status, tumour size, and grade.
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Affiliation(s)
- M Kaufmann
- Department of Obstetrics and Gynaecology, University of Heidelberg, Germany
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46
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Dall P, Heider KH, Sinn HP, Skroch-Angel P, Adolf G, Kaufmann M, Herrlich P, Ponta H. Comparison of immunohistochemistry and RT-PCR for detection of CD44v-expression, a new prognostic factor in human breast cancer. Int J Cancer 1995; 60:471-7. [PMID: 7530237 DOI: 10.1002/ijc.2910600408] [Citation(s) in RCA: 120] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
In different human tumors, splice variants of the surface glycoprotein CD44 (CD44v) are correlated with advanced stages of tumor growth and metastatic potential. In breast cancer and colon cancer, expression of epitopes encoded by exon v6 on primary tumors is an independent prognostic factor for poor patient survival. Two different screening methods for the detection of CD44 variants in tumors have been applied: immunohistochemistry (IHC) and semi-quantitative reverse transcription PCR (RT-PCR). In this study, we have compared the predictive capacity and the applicability of both approaches, using 31 human breast-tissue specimens (normal and neoplastic). IHC reveals lack of expression of CD44v on normal ductal epithelial cells but strong expression on myoepithelial cells. The majority of tumors express CD44 epitopes encoded by several variant exons. RT-PCR detects splice variants in normal epithelium, probably derived from RNA expressed in the myoepithelium. In tumors, RT-PCR reveals expression of a wide range of splice variants, including new ones that are not detected in normal breast tissue, e.g. ones that contain all variant exons. The conclusion of this comparison is that IHC is the better method for breast-tumor sample screening but that the increased sensitivity of RT-PCR can help to distinguish CD44v-positive from CD44v-negative tumors in cases where only a few tumor cells express variants or where epitopes are masked.
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MESH Headings
- Antigens, Neoplasm/analysis
- Antigens, Neoplasm/biosynthesis
- Antigens, Neoplasm/genetics
- Base Sequence
- Biomarkers, Tumor/analysis
- Biomarkers, Tumor/genetics
- Blotting, Southern
- Breast Neoplasms/diagnosis
- Breast Neoplasms/immunology
- Carcinoma in Situ/diagnosis
- Carcinoma in Situ/immunology
- Carcinoma, Ductal, Breast/diagnosis
- Carcinoma, Ductal, Breast/immunology
- Carcinoma, Intraductal, Noninfiltrating/diagnosis
- Carcinoma, Intraductal, Noninfiltrating/immunology
- Carcinoma, Lobular/diagnosis
- Carcinoma, Lobular/immunology
- Carrier Proteins/analysis
- Carrier Proteins/biosynthesis
- Carrier Proteins/genetics
- DNA, Neoplasm/genetics
- Epitopes/analysis
- Female
- Fibroadenoma/diagnosis
- Fibroadenoma/immunology
- Gene Expression
- Gene Expression Regulation, Neoplastic
- Humans
- Hyaluronan Receptors
- Immunohistochemistry
- Molecular Sequence Data
- Polymerase Chain Reaction/methods
- Predictive Value of Tests
- Prognosis
- Receptors, Cell Surface/analysis
- Receptors, Cell Surface/biosynthesis
- Receptors, Cell Surface/genetics
- Receptors, Lymphocyte Homing/analysis
- Receptors, Lymphocyte Homing/biosynthesis
- Receptors, Lymphocyte Homing/genetics
- Sensitivity and Specificity
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Affiliation(s)
- P Dall
- Nuclear Research Center Karlsruhe, Institute of Genetics, Germany
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47
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Sinn HP, Heider KH, Skroch-Angel P, von Minckwitz G, Kaufmann M, Herrlich P, Ponta H. Human mammary carcinomas express homologues of rat metastasis-associated variants of CD44. Breast Cancer Res Treat 1995; 36:307-313. [PMID: 8573713 DOI: 10.1007/bf00713402] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Splice variants of CD44 expressed in a metastasizing cell line derived from a rat pancreatic adenocarcinoma have been shown recently to confer metastatic potential onto non-metastasizing rat pancreatic carcinoma and sarcoma cell lines. Homologues of these variants have also been detected in a variety of human malignancies. Using antibodies raised against a bacterially expressed fusion protein containing variant CD44 sequences, we have explored the expression of variant CD44 glycoproteins on tumors of the female breast. The material examined included normal tissue, hyperplastic lesions, 103 primary invasive mammary carcinomas, 10 in situ carcinomas, 12 local recurrences and 18 lymph node metastases. Using a polyclonal serum directed against several variant CD44 epitopes, normal mammary epithelia as well as ductal hyperplasias were negative for these splice variants, while the variant CD44 epitopes were detectable in all but six of the primary invasive carcinomas. From the reaction with various monoclonal antibodies and polyclonal sera specific for individual epitopes it is obvious that the tumors predominantly express CD44 variants encoded by exons v5 to v7. Interestingly, all investigated lymph node metastases reacted positively with the variant-specific antibodies, in contrast to primary tumors which reacted in 54% to 86% of the cases, depending on the antibody used. Statistical analysis revealed a significant correlation between expression of variant exons v3/v4 and v6 and increased tumor grade (p = 0.001 and p < 0.05, respectively; Fisher's exact test). Exon v6 is carried by the variants which confer metastatic capability in the rat. These results indicate that the expression of the CD44 variants is upregulated in mammary carcinomas and is closely linked to tumor anaplasia.
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Affiliation(s)
- H P Sinn
- University of Heidelberg, Department of Pathology, Germany
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48
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Herrlich P, Ponta H. Mutual cross-modulation of steroid/retinoic acid receptor and AP-1 transcription factor activities: a novel property with practical implications. Trends Endocrinol Metab 1994; 5:341-6. [PMID: 18407228 DOI: 10.1016/1043-2760(94)90164-3] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Nuclear receptors and the AP-1 transcription factors (homodimers and heterodimers of members of the Jun/Fos/ATF/families) mutually influence their activities, positively and negatively. Mutual negative interference is of practical importance as it can be exploited for therapy of human diseases. Since the discovery of cross-modulation, many reports, seemingly not always compatible, have appeared. Recent experimental evidence may help to develop a model for this interesting transcription factor interaction that satisfies most observations. Transactivation and transrepression (as one facet o f cross-modulation) are separable activities o f the nuclear receptors. The modulating property appears to be exerted by nuclear receptor monomers. These conclusions are supported by point mutations in the glucocorticoid receptor and by the specific inhibitory effects of ligand analogues on transactivation only. These pilot experiments make a search for ligands that enhance the cross-modulatory function without triggering transactivation very promising.
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Affiliation(s)
- P Herrlich
- Karlsruhe Nuclear Research Center, Institute for Genetics, Karlsruhe, Germany
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49
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Abstract
Hyaluronate (HA) is an abundant component of extracellular matrix that is believed to be crucial in many cellular processes, including tissue remodeling, the creation of cell-free spaces, inflammation and tumorigenesis. Although several well characterized proteins within the extracellular matrix associate with HA, it is now clear that cells can also bind and respond to HA directly, via cell-surface HA-binding proteins. The cDNAs coding for two families of such proteins, CD44 and RHAMM, have been cloned and characterized. These proteins have been implicated in a number of physiological processes, including cell migration, lymphocyte activation and tumor progression. Although many of these processes depend on an association with HA, some are apparently HA-independent, suggesting that other ligands for these receptors may be involved.
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Affiliation(s)
- L Sherman
- Institut für Genetik, Kernforschungszentrum Karlsruhe, Germany
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50
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Heck S, Kullmann M, Gast A, Ponta H, Rahmsdorf HJ, Herrlich P, Cato AC. A distinct modulating domain in glucocorticoid receptor monomers in the repression of activity of the transcription factor AP-1. EMBO J 1994; 13:4087-95. [PMID: 8076604 PMCID: PMC395330 DOI: 10.1002/j.1460-2075.1994.tb06726.x] [Citation(s) in RCA: 383] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Steroid receptors activate and repress genes. An important class of genes that they repress is controlled by the transcription factor AP-1. The activity of AP-1 is inhibited by the receptor, a mechanism exploited for the therapy of various forms of pathological hyperproliferation in humans. We show here by point mutations in the DNA binding domain and by the choice of steroid ligands that repression of AP-1 activity and transactivation functions of the glucocorticoid receptor (GR) are separable entities. While DNA binding and activation of glucocorticoid-regulated promoters require GR dimerization, we present data that suggest that repression is a function of GR monomers.
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Affiliation(s)
- S Heck
- Kernforschungszentrum Karlsruhe, Institut für Genetik, Germany
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