51
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Lange C, Ehlken C, Martin G, Konzok K, Moscoso Del Prado J, Hansen LL, Agostini HT. Intravitreal injection of the heparin analog 5-amino-2-naphthalenesulfonate reduces retinal neovascularization in mice. Exp Eye Res 2007; 85:323-7. [PMID: 17662276 DOI: 10.1016/j.exer.2007.05.007] [Citation(s) in RCA: 15] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2006] [Revised: 05/29/2007] [Accepted: 05/30/2007] [Indexed: 11/16/2022]
Abstract
The effect of the heparin analog 5-amino-2-naphthalenesulfonate (5-amino-2-NMS) on retinal neovascularization was investigated in the mouse model for oxygen-induced retinopathy (OIR). From postnatal day 7 (P7) until P12, mice were kept in a 75% oxygen environment. On P12, they received an intravitreal injection of 10mM 5-amino-2-NMS in one eye and PBS as control substance in the fellow eye. The animals were intracardially perfused with fluorescein-dextran solution on P17. Retinal whole mounts were prepared and ischemic retinopathy was evaluated in 30 animals using a standardized retinopathy score. A single intravitreal injection of 5-amino-2-NMS reduces significantly angioproliferative changes (blood vessel tufts, extra-retinal neovascularization, and blood vessel tortuosity) compared to the contralateral control eye (p=0.025). The median retinopathy score (maximal 13) for the 5-amino-2-NMS treated eyes was 6 versus 8 for the control eyes. 5-Amino-2-NMS binds to the heparin-binding site of FGF1 and FGF2 and thus may be a promising substance for the local treatment of retinal neovascularization.
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Affiliation(s)
- Clemens Lange
- Augenklinik, Universitätsklinikum Freiburg, Killianstrasse 5, 79106 Freiburg, Germany
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52
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Goldbeter A, Gonze D, Pourquié O. Sharp developmental thresholds defined through bistability by antagonistic gradients of retinoic acid and FGF signaling. Dev Dyn 2007; 236:1495-508. [PMID: 17497689 DOI: 10.1002/dvdy.21193] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
The establishment of thresholds along morphogen gradients in the embryo is poorly understood. Using mathematical modeling, we show that mutually inhibitory gradients can generate and position sharp morphogen thresholds in the embryonic space. Taking vertebrate segmentation as a paradigm, we demonstrate that the antagonistic gradients of retinoic acid (RA) and Fibroblast Growth Factor (FGF) along the presomitic mesoderm (PSM) may lead to the coexistence of two stable steady states. Here, we propose that this bistability is associated with abrupt switches in the levels of FGF and RA signaling, which permit the synchronized activation of segmentation genes, such as mesp2, in successive cohorts of PSM cells in response to the segmentation clock, thereby defining the future segments. Bistability resulting from mutual inhibition of RA and FGF provides a molecular mechanism for the all-or-none transitions assumed in the "clock and wavefront" somitogenesis model. Given that mutually antagonistic signaling gradients are common in development, such bistable switches could represent an important principle underlying embryonic patterning.
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Affiliation(s)
- Albert Goldbeter
- Faculté des Sciences, Université Libre de Bruxelles, U.L.B., Brussels, Belgium
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53
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Niwa Y, Masamizu Y, Liu T, Nakayama R, Deng CX, Kageyama R. The Initiation and Propagation of Hes7 Oscillation Are Cooperatively Regulated by Fgf and Notch Signaling in the Somite Segmentation Clock. Dev Cell 2007; 13:298-304. [PMID: 17681139 DOI: 10.1016/j.devcel.2007.07.013] [Citation(s) in RCA: 151] [Impact Index Per Article: 8.9] [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: 02/07/2007] [Revised: 04/24/2007] [Accepted: 07/18/2007] [Indexed: 02/06/2023]
Abstract
Periodic formation of somites is controlled by the segmentation clock, where the oscillator Hes7 regulates cyclic expression of the Notch modulator Lunatic fringe. Here, we show that Hes7 also regulates cyclic expression of the Fgf signaling inhibitor Dusp4 and links Notch and Fgf oscillations in phase. Strikingly, inactivation of Notch signaling abolishes the propagation but allows the initiation of Hes7 oscillation. By contrast, transient inactivation of Fgf signaling abolishes the initiation, whereas sustained inactivation abolishes both the initiation and propagation of Hes7 oscillation. We thus propose that Hes7 oscillation is initiated by Fgf signaling and propagated/maintained anteriorly by Notch signaling.
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Affiliation(s)
- Yasutaka Niwa
- Institute for Virus Research, Kyoto University, Kyoto 606-8507, Japan
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54
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Rolland Y, Demeule M, Michaud-Levesque J, Béliveau R. Inhibition of tumor growth by a truncated and soluble form of melanotransferrin. Exp Cell Res 2007; 313:2910-9. [PMID: 17493610 DOI: 10.1016/j.yexcr.2007.04.013] [Citation(s) in RCA: 9] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2007] [Revised: 04/04/2007] [Accepted: 04/09/2007] [Indexed: 11/20/2022]
Abstract
Melanotransferrin is a glycoprotein expressed at the cell membrane and secreted in the extracellular environment. Recombinant truncated form of membrane-bound melanotransferrin (sMTf) was reported to exert in vitro anti-angiogenic properties. Here we show that sMTf treatment leads to a 50% inhibition of neovascularization in Matrigel implants when stimulated by growth factors. Using a glioblastoma xenograft model, we demonstrate that sMTf delivery at 2.5 and 10 mg/kg/day by micro-osmotic pump inhibits tumor growth by 73% and 91%, respectively. In a lung carcinoma xenograft model, sMTf treatment at 2.5 and 10 mg/kg/day impeded tumor growth by 87% and 97%. Furthermore, subcutaneous glioblastoma and lung carcinoma tumors from mice treated with 10 mg/kg/day of sMTf present insignificant growth toward the study. In association with a reduction in endoglin mRNA expression, the hemoglobin content decreased by half in sMTf-treated glioblastoma tumors. In vitro experiments revealed that NCI-H460 cells treated with sMTf display an inhibition in their invasive capabilities with a concomitant reduction in the expression of the low-density lipoprotein receptor protein and urokinase plasminogen activator receptor. Altogether, our results demonstrate that sMTf exerts anti-cancer and anti-angiogenic activities, suggesting that its administration may provide novel therapeutic strategies for the treatment of cancer.
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Affiliation(s)
- Yannève Rolland
- Laboratoire de Médecine Moléculaire, Service d'Hémato-Oncologie, Hôpital Ste-Justine - Université du Québec à Montréal, Succursale Centre-ville, Montréal, Québec, Canada
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55
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Welsh IC, Hagge-Greenberg A, O'Brien TP. A dosage-dependent role for Spry2 in growth and patterning during palate development. Mech Dev 2007; 124:746-61. [PMID: 17693063 PMCID: PMC2043129 DOI: 10.1016/j.mod.2007.06.007] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2007] [Revised: 06/12/2007] [Accepted: 06/30/2007] [Indexed: 11/28/2022]
Abstract
The formation of the palate involves the coordinated outgrowth, elevation and midline fusion of bilateral shelves leading to the separation of the oral and nasal cavities. Reciprocal signaling between adjacent fields of epithelial and mesenchymal cells directs palatal shelf growth and morphogenesis. Loss of function mutations in genes encoding FGF ligands and receptors have demonstrated a critical role for FGF signaling in mediating these epithelial-mesenchymal interactions. The Sprouty family of genes encode modulators of FGF signaling. We have established that mice carrying a deletion that removes the FGF signaling antagonist Spry2 have cleft palate. We show that excessive cell proliferation in the Spry2-deficient palate is accompanied by the abnormal progression of shape changes and movements required for medially directed shelf outgrowth and midline contact. Expression of the FGF responsive transcription factors Etv5, Msx1, and Barx1, as well as the morphogen Shh, is restricted to specific regions of the developing palate. We detected elevated and ectopic expression of these transcription factors and disorganized Shh expression in the Spry2-deficient palate. Mice carrying a targeted disruption of Spry2 fail to complement the craniofacial phenotype characterized in Spry2 deletion mice. Furthermore, a Spry2-BAC transgene rescues the palate defect. However, the BAC transgenic mouse lines express reduced levels of Spry2. The resulting hypomorphic phenotype demonstrates that palate development is Spry2 dosage sensitive. Our results demonstrate the importance of proper FGF signaling thresholds in regulation of epithelial-mesenchymal interactions and cellular responses necessary for coordinated morphogenesis of the face and palate.
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Affiliation(s)
- Ian C Welsh
- Department of Biomedical Sciences, Cornell University, Ithaca, NY 14853, USA
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56
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Abstract
Angiogenesis, the process of new blood vessel formation from pre-existing ones, plays a key role in various physiological and pathological conditions, including embryonic development, wound repair, inflammation, and tumor growth. The 1980s saw for the first time the identification, purification, and sequencing of the two prototypic heparin-binding angiogenic fibroblast growth factors (FGF) 1 and 2. Since then, 22 structurally-related members of the FGF family and different classes of FGF receptors have been identified. Several experimental evidences point to a role for various FGFs in the neovascularization process that takes place in inflammation, angioproliferative diseases, and tumor growth. Thus, the FGF/FGF receptor system represents a target for the development of anti-angiogenic therapies. Purpose of this review is to summarize the different modalities that have been approached to impair the pro-angiogenic activity of the FGF/FGF receptor system and discuss their possible therapeutic implications.
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Affiliation(s)
- M Rusnati
- Unit of General Pathology and Immunology, Department of Biomedical Sciences and Biotechnology, School of Medicine, University of Brescia, Italy
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57
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Desnoyers LR, Pai R, Ferrando RE, Hötzel K, Le T, Ross J, Carano R, D'Souza A, Qing J, Mohtashemi I, Ashkenazi A, French DM. Targeting FGF19 inhibits tumor growth in colon cancer xenograft and FGF19 transgenic hepatocellular carcinoma models. Oncogene 2007; 27:85-97. [PMID: 17599042 DOI: 10.1038/sj.onc.1210623] [Citation(s) in RCA: 204] [Impact Index Per Article: 12.0] [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: 12/11/2022]
Abstract
Although fibroblast growth factor 19 (FGF19) can promote liver carcinogenesis in mice its involvement in human cancer is not well characterized. Here we report that FGF19 and its cognate receptor FGF receptor 4 (FGFR4) are coexpressed in primary human liver, lung and colon tumors and in a subset of human colon cancer cell lines. To test the importance of FGF19 for tumor growth, we developed an anti-FGF19 monoclonal antibody that selectively blocks the interaction of FGF19 with FGFR4. This antibody abolished FGF19-mediated activity in vitro and inhibited growth of colon tumor xenografts in vivo and effectively prevented hepatocellular carcinomas in FGF19 transgenic mice. The efficacy of the antibody in these models was linked to inhibition of FGF19-dependent activation of FGFR4, FRS2, ERK and beta-catenin. These findings suggest that the inactivation of FGF19 could be beneficial for the treatment of colon cancer, liver cancer and other malignancies involving interaction of FGF19 and FGFR4.
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MESH Headings
- Animals
- Antibodies, Blocking/therapeutic use
- Antibodies, Monoclonal/therapeutic use
- Antineoplastic Agents/pharmacology
- Carcinoma, Hepatocellular/drug therapy
- Carcinoma, Hepatocellular/genetics
- Carcinoma, Hepatocellular/immunology
- Carcinoma, Squamous Cell/drug therapy
- Carcinoma, Squamous Cell/immunology
- Carcinoma, Squamous Cell/metabolism
- Colonic Neoplasms/drug therapy
- Colonic Neoplasms/genetics
- Colonic Neoplasms/immunology
- Fibroblast Growth Factors/antagonists & inhibitors
- Fibroblast Growth Factors/biosynthesis
- Fibroblast Growth Factors/genetics
- Fibroblast Growth Factors/immunology
- Gene Targeting/methods
- HCT116 Cells
- HT29 Cells
- Humans
- Liver Neoplasms, Experimental/drug therapy
- Liver Neoplasms, Experimental/immunology
- Lung Neoplasms/drug therapy
- Lung Neoplasms/genetics
- Lung Neoplasms/immunology
- Mice
- Mice, Inbred BALB C
- Mice, Nude
- Mice, Transgenic
- Neoplasm Transplantation
- Receptor, Fibroblast Growth Factor, Type 4/biosynthesis
- Receptor, Fibroblast Growth Factor, Type 4/genetics
- Receptor, Fibroblast Growth Factor, Type 4/metabolism
- Transplantation, Heterologous
- Xenograft Model Antitumor Assays/methods
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Affiliation(s)
- L R Desnoyers
- 1Department of Molecular Oncology, Genentech Inc., South San Francisco, CA, USA
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58
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Badman MK, Pissios P, Kennedy AR, Koukos G, Flier JS, Maratos-Flier E. Hepatic fibroblast growth factor 21 is regulated by PPARalpha and is a key mediator of hepatic lipid metabolism in ketotic states. Cell Metab 2007; 5:426-37. [PMID: 17550778 DOI: 10.1016/j.cmet.2007.05.002] [Citation(s) in RCA: 1175] [Impact Index Per Article: 69.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/18/2007] [Revised: 04/06/2007] [Accepted: 05/03/2007] [Indexed: 02/06/2023]
Abstract
Mice fed a high-fat, low-carbohydrate ketogenic diet (KD) exhibit marked changes in hepatic metabolism and energy homeostasis. Here, we identify liver-derived fibroblast growth factor 21 (FGF21) as an endocrine regulator of the ketotic state. Hepatic expression and circulating levels of FGF21 are induced by both KD and fasting, are rapidly suppressed by refeeding, and are in large part downstream of PPARalpha. Importantly, adenoviral knockdown of hepatic FGF21 in KD-fed mice causes fatty liver, lipemia, and reduced serum ketones, due at least in part to altered expression of key genes governing lipid and ketone metabolism. Hence, induction of FGF21 in liver is required for the normal activation of hepatic lipid oxidation, triglyceride clearance, and ketogenesis induced by KD. These findings identify hepatic FGF21 as a critical regulator of lipid homeostasis and identify a physiological role for this hepatic hormone.
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Affiliation(s)
- Michael K Badman
- Division of Endocrinology, Department of Medicine, Beth Israel Deaconess Medical Center, 330 Brookline Avenue, Boston, MA 02215, USA
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59
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Furushima K, Yamamoto A, Nagano T, Shibata M, Miyachi H, Abe T, Ohshima N, Kiyonari H, Aizawa S. Mouse homologues of Shisa antagonistic to Wnt and Fgf signalings. Dev Biol 2007; 306:480-92. [PMID: 17481602 DOI: 10.1016/j.ydbio.2007.03.028] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [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: 11/20/2006] [Revised: 03/12/2007] [Accepted: 03/19/2007] [Indexed: 12/28/2022]
Abstract
In an effort to identify Otx2 targets in mouse anterior neuroectoderm we identified a gene, mShisa, which is homologous to xShisa1 that we previously reported as a head inducer in Xenopus. mShisa encodes an antagonist against both Wnt and Fgf signalings; it inhibits these signalings cell-autonomously as xShisa1 does. The mShisa expression is lost or greatly reduced in Otx2 mutant visceral endoderm, anterior mesendoderm and anterior neuroectoderm. However, mShisa mutants exhibited no defects in head development. Shisa is composed of five subfamilies, but normal head development in mShisa mutants is unlikely to be explained in terms of the compensation of mShisa deficiency by its paralogues or by known Wnt antagonists in anterior visceral endoderm and/or anterior mesendoderm.
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Affiliation(s)
- Kenryo Furushima
- Laboratory for Animal Resources and Genetic Engineering, Center for Developmental Biology (CDB), RIKEN Kobe, 2-2-3 Minatojima Minami, Chuo-ku, Kobe 650-0047, Japan
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60
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Li C, Scott DA, Hatch E, Tian X, Mansour SL. Dusp6 (Mkp3) is a negative feedback regulator of FGF-stimulated ERK signaling during mouse development. Development 2007; 134:167-76. [PMID: 17164422 PMCID: PMC2424197 DOI: 10.1242/dev.02701] [Citation(s) in RCA: 221] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Mitogen-activated protein kinase (MAPK) pathways are major mediators of extracellular signals that are transduced to the nucleus. MAPK signaling is attenuated at several levels, and one class of dual-specificity phosphatases, the MAPK phosphatases (MKPs), inhibit MAPK signaling by dephosphorylating activated MAPKs. Several of the MKPs are themselves induced by the signaling pathways they regulate, forming negative feedback loops that attenuate the signals. We show here that in mouse embryos, Fibroblast growth factor receptors (FGFRs) are required for transcription of Dusp6, which encodes MKP3, an extracellular signal-regulated kinase (ERK)-specific MKP. Targeted inactivation of Dusp6 increases levels of phosphorylated ERK, as well as the pERK target, Erm, and transcripts initiated from the Dusp6 promoter itself. Finally, the Dusp6 mutant allele causes variably penetrant, dominant postnatal lethality, skeletal dwarfism, coronal craniosynostosis and hearing loss; phenotypes that are also characteristic of mutations that activate FGFRs inappropriately. Taken together, these results show that DUSP6 serves in vivo as a negative feedback regulator of FGFR signaling and suggest that mutations in DUSP6 or related genes are candidates for causing or modifying unexplained cases of FGFR-like syndromes.
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Affiliation(s)
- Chaoying Li
- Department of Human Genetics, University of Utah, Salt Lake City, UT 84112-5330, USA
| | - Daryl A. Scott
- Department of Human Genetics, University of Utah, Salt Lake City, UT 84112-5330, USA
| | - Ekaterina Hatch
- Department of Human Genetics, University of Utah, Salt Lake City, UT 84112-5330, USA
| | - Xiaoyan Tian
- Department of Radiology (Division of Radiobiology), University of Utah, Salt Lake City, UT 84112-5330, USA
| | - Suzanne L. Mansour
- Department of Human Genetics, University of Utah, Salt Lake City, UT 84112-5330, USA
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61
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Huang X, Yu C, Jin C, Yang C, Xie R, Cao D, Wang F, McKeehan WL. Forced expression of hepatocyte-specific fibroblast growth factor 21 delays initiation of chemically induced hepatocarcinogenesis. Mol Carcinog 2007; 45:934-42. [PMID: 16929488 DOI: 10.1002/mc.20241] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Inappropriate fibroblast growth factor (FGF) signaling is involved in most tissue-specific pathologies including cancer. Previously we showed that inappropriate expression and chronic activity of FGF receptor (FGFR) 1 in hepatocytes accelerated diethylnitrosamine (DEN)-initiated hepatocarcinogenesis. Here we showed that although widely expressed FGF1 and FGF2 are frequently upregulated in hepatocellular carcinoma (HCC), germline deletion of both FGF1 and FGF2 had no effect on DEN-initiated hepatocarcinogenesis. Thus overexpression of FGF1 or FGF2 may be a consequence rather than contributor to hepatoma progression. FGF21 is the first of 22 homologues whose expression has been reported to be preferentially in the liver. We showed that similar to FGF1 and FGF2, FGF21 mRNA was upregulated in neoplastic and regenerating liver after partial hepatectomy (PH) and CCl4 administration. In situ hybridization analysis confirmed that in contrast to FGF1 and FGF2, expression of FGF21 mRNA was limited to hepatocytes. Forced overexpression of FGF21 in hepatocytes by gene targeting had no apparent impact on normal liver development and compensatory response to injury. Surprisingly, overexpression of FGF21 delayed the appearance of DEN-induced liver tumors. At 8 and 10 mo, only 10% and 30% of transgenic mice, respectively, developed adenomas compared to 50% (all adenomas) and 80% (60% adenoma/20% HCC) in the wild-type (WT) mice. However, the incidence and burden of HCC at 10 mo and later was equal in the FGF21 transgenic and WT mice. We propose that FGF21 may delay development of adenomas through activation of resident hepatocyte FGFR4 at early times, but counteracts the delay by acceleration of progression to HCC through interaction with ectopic FGFR1 once it appears in hepatoma cells. This indicates a dual function of FGF21 that may reflect changes in FGFR isotype during progression of differentiated hepatoma cells.
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MESH Headings
- Animals
- Carbon Tetrachloride/toxicity
- Carcinoma, Hepatocellular/chemically induced
- Carcinoma, Hepatocellular/genetics
- Carcinoma, Hepatocellular/pathology
- Cell Transformation, Neoplastic/chemically induced
- Cell Transformation, Neoplastic/genetics
- Cell Transformation, Neoplastic/pathology
- Fibroblast Growth Factor 1/antagonists & inhibitors
- Fibroblast Growth Factor 1/genetics
- Fibroblast Growth Factor 1/physiology
- Fibroblast Growth Factor 2/antagonists & inhibitors
- Fibroblast Growth Factor 2/genetics
- Fibroblast Growth Factor 2/physiology
- Fibroblast Growth Factors/antagonists & inhibitors
- Fibroblast Growth Factors/genetics
- Fibroblast Growth Factors/physiology
- Gene Targeting
- Hepatocytes/metabolism
- Hepatocytes/pathology
- Liver Neoplasms/chemically induced
- Liver Neoplasms/genetics
- Liver Neoplasms/pathology
- Mice
- Mice, Transgenic
- RNA, Messenger/analysis
- RNA, Messenger/metabolism
- Receptor, Fibroblast Growth Factor, Type 4/agonists
- Receptor, Fibroblast Growth Factor, Type 4/metabolism
- Transcriptional Activation
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Affiliation(s)
- Xinqiang Huang
- Center for Cancer Biology and Nutrition, Institute of Biosciences and Technology, Texas A&M University System Health Science Center, Houston, Texas 77030, USA
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62
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Ren Y, Li Z, Rong Z, Cheng L, Li Y, Wang Z, Chang Z. Tyrosine 330 in hSef is critical for the localization and the inhibitory effect on FGF signaling. Biochem Biophys Res Commun 2007; 354:741-6. [PMID: 17266935 DOI: 10.1016/j.bbrc.2007.01.037] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [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: 01/07/2007] [Accepted: 01/09/2007] [Indexed: 11/16/2022]
Abstract
Sef (similar expression to fgf genes) was identified as an inhibitor of FGF signaling. The regulation of this inhibitory effect was largely unknown. In this report we demonstrated that tyrosine 330 in hSef protein plays a critical role in the control of the protein localization and thereby in the regulation of Ras/MAPK signaling pathway. We found that the tyrosine 330 is in the form of the YXXcapital EF, Cyrillic signal context and mutation of this residue resulted in preferred plasma membrane localization of hSef. We also observed that both Sef and SefY330F (where tyrosine is substituted by phenylalanine) interacted and co-localized with FGFR in the co-immunoprecipitation assay, and immunostaining assay respectively. We further revealed that the increased amount of Sef localization in the plasma membrane was coupled with the enhanced inhibitory effect on the FGF signaling pathway, indicating that Sef might exert its inhibitory function on the plasma membrane. This paper revealed that tyrosine 330 is critical for the inhibitory function of Sef on FGF signaling.
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Affiliation(s)
- Yongming Ren
- Department of Biological Sciences and Biotechnology, School of Medicine, Institute of Biomedicine, State Key Laboratory of Biomembrane and Membrane Biotechnology, Tsinghua University, Beijing, China
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63
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Kovalenko D, Yang X, Chen PY, Nadeau RJ, Zubanova O, Pigeon K, Friesel R. A role for extracellular and transmembrane domains of Sef in Sef-mediated inhibition of FGF signaling. Cell Signal 2006; 18:1958-66. [PMID: 16603339 DOI: 10.1016/j.cellsig.2006.03.001] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2006] [Revised: 03/02/2006] [Accepted: 03/03/2006] [Indexed: 11/28/2022]
Abstract
Sef (similar expression to fgf genes) is a member of the fibroblast growth factor (FGF) synexpression group that negatively regulates FGF receptor (FGFR) signaling in zebrafish during early embryonic development and in mammalian cell culture systems. The mechanism by which Sef exerts its inhibitory effect remains controversial. It has been reported that Sef functions either through binding to and inhibiting FGFR1 activation or by acting downstream of FGF receptors at the level of MEK/ERK kinases. In both cases, the intracellular domain of Sef was found to play a role in the inhibitory function of Sef. Here we demonstrated that both extracellular and transmembrane domains of Sef contributed to Sef-mediated negative regulation of FGF signaling. In fact, over-expression studies in NIH3T3 cells showed that a truncated mutant of Sef, which lacks the intracellular domain (SefECTM), exerted the inhibitory activity on FGF signaling by inhibiting FGFR1 tyrosine phosphorylation and subsequent activation of the Raf/MEK/ERK signaling cascade. We also showed that SefECTM associated with FGFR1, and inhibited FGF-induced ERK activation in HEK293T cells. Furthermore, we demonstrated that the over-expression of SefECTM was able to inhibit the function of a constitutively activated form of FGFR1, FGFR1-C289R, but not FGFR1-K562E. Finally, we found that SefECTM reduced cell viability when over-expressed in human umbilical vein endothelial cells (HUVEC). These data provide additional insight into the structure-activity relationship in the mechanism of inhibitory action of Sef on FGFR1-mediated signaling.
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Affiliation(s)
- Dmitry Kovalenko
- Center for Molecular Medicine, Maine Medical Center Research Institute, 81 Research Drive, Scarborough, ME 04074-7205, USA
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64
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Urakawa I, Yamazaki Y, Shimada T, Iijima K, Hasegawa H, Okawa K, Fujita T, Fukumoto S, Yamashita T. Klotho converts canonical FGF receptor into a specific receptor for FGF23. Nature 2006; 444:770-4. [PMID: 17086194 DOI: 10.1038/nature05315] [Citation(s) in RCA: 1315] [Impact Index Per Article: 73.1] [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: 04/12/2006] [Accepted: 10/09/2006] [Indexed: 12/29/2022]
Abstract
FGF23 is a unique member of the fibroblast growth factor (FGF) family because it acts as a hormone that derives from bone and regulates kidney functions, whereas most other family members are thought to regulate various cell functions at a local level. The renotropic activity of circulating FGF23 indicates the possible presence of an FGF23-specific receptor in the kidney. Here we show that a previously undescribed receptor conversion by Klotho, a senescence-related molecule, generates the FGF23 receptor. Using a renal homogenate, we found that Klotho binds to FGF23. Forced expression of Klotho enabled the high-affinity binding of FGF23 to the cell surface and restored the ability of a renal cell line to respond to FGF23 treatment. Moreover, FGF23 incompetence was induced by injecting wild-type mice with an anti-Klotho monoclonal antibody. Thus, Klotho is essential for endogenous FGF23 function. Because Klotho alone seemed to be incapable of intracellular signalling, we searched for other components of the FGF23 receptor and found FGFR1(IIIc), which was directly converted by Klotho into the FGF23 receptor. Thus, the concerted action of Klotho and FGFR1(IIIc) reconstitutes the FGF23 receptor. These findings provide insights into the diversity and specificity of interactions between FGF and FGF receptors.
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Affiliation(s)
- Itaru Urakawa
- Pharmaceutical Research Laboratories, Kirin Brewery Co., Ltd, 3 Miyahara, Takasaki, Gunma 370-1295, Japan.
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65
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Klein OD, Minowada G, Peterkova R, Kangas A, Yu BD, Lesot H, Peterka M, Jernvall J, Martin GR. Sprouty genes control diastema tooth development via bidirectional antagonism of epithelial-mesenchymal FGF signaling. Dev Cell 2006; 11:181-90. [PMID: 16890158 PMCID: PMC2847684 DOI: 10.1016/j.devcel.2006.05.014] [Citation(s) in RCA: 236] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2006] [Revised: 05/16/2006] [Accepted: 05/18/2006] [Indexed: 11/26/2022]
Abstract
Unlike humans, who have a continuous row of teeth, mice have only molars and incisors separated by a toothless region called a diastema. Although tooth buds form in the embryonic diastema, they regress and do not develop into teeth. Here, we identify members of the Sprouty (Spry) family, which encode negative feedback regulators of fibroblast growth factor (FGF) and other receptor tyrosine kinase signaling, as genes that repress diastema tooth development. We show that different Sprouty genes are deployed in different tissue compartments--Spry2 in epithelium and Spry4 in mesenchyme--to prevent diastema tooth formation. We provide genetic evidence that they function to ensure that diastema tooth buds are refractory to signaling via FGF ligands that are present in the region and thus prevent these buds from engaging in the FGF-mediated bidirectional signaling between epithelium and mesenchyme that normally sustains tooth development.
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Affiliation(s)
- Ophir D. Klein
- Department of Anatomy and Program in Developmental Biology, School of Medicine, University of California, San Francisco, San Francisco, California 94143
- Department of Pediatrics, School of Medicine, University of California, San Francisco, San Francisco, California 94143
| | - George Minowada
- Department of Anatomy and Program in Developmental Biology, School of Medicine, University of California, San Francisco, San Francisco, California 94143
- Department of Medicine, Division of Pulmonary and Critical Care Medicine, Case Western Reserve University, School of Medicine, University Hospitals of Cleveland, Cleveland, Ohio 44106
| | - Renata Peterkova
- Department of Teratology, Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Aapo Kangas
- Developmental Biology Program, Institute of Biotechnology, Viikki Biocenter, Post Office Box 56, University of Helsinki, FIN-00014, Helsinki, Finland
| | - Benjamin D. Yu
- Department of Anatomy and Program in Developmental Biology, School of Medicine, University of California, San Francisco, San Francisco, California 94143
- Department of Dermatology, School of Medicine, University of California, San Francisco, San Francisco, California 94143
| | - Herve Lesot
- INSERM UMR-595, Faculty of Medicine, 67085 Strasbourg, France
- University of Louis Pasteur, Faculté de Chirurgie Dentaire, 67085 Strasbourg, France
| | - Miroslav Peterka
- Department of Teratology, Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Jukka Jernvall
- Developmental Biology Program, Institute of Biotechnology, Viikki Biocenter, Post Office Box 56, University of Helsinki, FIN-00014, Helsinki, Finland
| | - Gail R. Martin
- Department of Anatomy and Program in Developmental Biology, School of Medicine, University of California, San Francisco, San Francisco, California 94143
- Correspondence:
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66
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Calmont A, Wandzioch E, Tremblay KD, Minowada G, Kaestner KH, Martin GR, Zaret KS. An FGF response pathway that mediates hepatic gene induction in embryonic endoderm cells. Dev Cell 2006; 11:339-48. [PMID: 16950125 DOI: 10.1016/j.devcel.2006.06.015] [Citation(s) in RCA: 96] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2006] [Revised: 06/05/2006] [Accepted: 06/27/2006] [Indexed: 01/03/2023]
Abstract
While particular combinations of mesodermal signals are known to induce distinct tissue-specific programs in the endoderm, there is little information about the response pathways within endoderm cells that control their specification. We have used signaling inhibitors on embryo tissue explants and whole-embryo cultures as well as genetic approaches to reveal part of an intracellular network by which FGF signaling helps induce hepatic genes and stabilize nascent hepatic cells within the endodermal epithelium. Specifically, we found that hepatic gene induction is elicited by an FGF/MAPK pathway. Although the PI3K pathway is activated in foregut endoderm cells, its inhibition does not block hepatic gene induction in explants; however, it does block tissue growth. We also found that at the onset of hepatogenesis, the FGF/MAPK and PI3K pathways do not crossregulate in the endoderm. The finding of separate pathways for endoderm tissue specification and growth provides insights for guiding cellular regeneration and stem cell differentiation.
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Affiliation(s)
- Amélie Calmont
- Cell and Developmental Biology Program, Fox Chase Cancer Center, 333 Cottman Avenue, Philadelphia, Pennsylvania 19111, USA
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67
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Sander TL, Noll L, Klinkner DB, Weihrauch D, He BJ, Kaul S, Zangwill SD, Tweddell JS, Pritchard KA, Oldham KT. Rosiglitazone antagonizes vascular endothelial growth factor signaling and nuclear factor of activated T cells activation in cardiac valve endothelium. ACTA ACUST UNITED AC 2006; 13:181-90. [PMID: 16840174 DOI: 10.1080/10623320600760308] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [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: 02/07/2023]
Abstract
Nuclear factor of activated T cells, Cytoplasmic 1 (NFATc1) is required for heart valve formation. Vascular endothelial growth factor (VEGF) signaling, mediated by NFATc1 activation, positively regulates growth of valvular endothelial cells. However, regulators of VEGF/NFATc1 signaling in valve endothelium are poorly understood. Peroxisome proliferator-activated receptor gamma (PPARgamma) inhibits NFATc1 activity in T cells and cardiomyocytes, but it is not known if PPARgamma controls NFATc1 function in endothelial cells. The authors hypothesize PPARgamma antagonizes VEGF signaling in valve endothelium by inhibiting NFATc1. Endothelial cells isolated from human valve leaflet tissue were shown by immunocytochemistry to express the endothelial-specific markers von Willebrand factor (vWF) and platelet endothelial cell adhesion molecule (PECAM)-1. VEGF-induced proliferation and migration of human pulmonary valve endothelial cells (HPVECs) were inhibited by rosiglitazone (ROSI), a specific ligand of PPARgamma activation, suggesting that PPARgamma disrupts VEGF signaling in the valve endothelium. ROSI also antagonized VEGF-mediated NFATc1 nuclear translocation in HPVECs, suggesting that PPARgamma inhibits VEGF signaling of NFATc1 activation in the valve. The effect of ROSI on nonvalve human umbilical vein endothelial cells (HUVECs) was tested in parallel and a similar inhibition of NFATc1 activation was observed. These data provide the first demonstration that ROSI negatively regulates VEGF signaling in the valve endothelium by a mechanism involving NFATc1 activation and nuclear translocation.
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Affiliation(s)
- Tara L Sander
- Department of Surgery, Medical College of Wisconsin and Children's Research Institute, Milwaukee, Wisconsin 53226, USA.
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68
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Mizoguchi T, Izawa T, Kuroiwa A, Kikuchi Y. Fgf signaling negatively regulates Nodal-dependent endoderm induction in zebrafish. Dev Biol 2006; 300:612-22. [PMID: 17026981 DOI: 10.1016/j.ydbio.2006.08.073] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [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: 03/07/2006] [Revised: 08/22/2006] [Accepted: 08/25/2006] [Indexed: 11/21/2022]
Abstract
In zebrafish development, Nodal signaling is critical for the induction of endoderm and mesoderm. Three transcription factors downstream of Nodal, Bonnie and Clyde (Bon), Faust (Fau)/Gata5 and Casanova (Cas), are required for endoderm induction. However, it is not yet fully understood how the Nodal signaling pathway regulates the decision process of endoderm and mesoderm induction. In this study, we focused on Fgf signaling, downstream of Nodal signaling, during endoderm induction. We found that activation of Fgf signaling decreases the number of cas-expressing endodermal cells. Conversely, inhibition of this signaling increases the number of endodermal cells without affecting the expression of Nodal, Nodal antagonists, bon or fau/gata5. Inhibition of Fgf signaling in endoderm mutants suggests that this signaling negatively regulates cas expression by a pathway parallel to Bon and Fau/Gata5 in the molecular cascade leading to endoderm. Furthermore, activation of Fgf signaling can overcome Cas-mediated abrogation of mesodermal gene expression. Altogether, these results suggest that Fgf signaling negatively regulates endoderm induction, possibly through repression of cas expression and down-regulation of Cas function.
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Affiliation(s)
- Takamasa Mizoguchi
- Division of Biological Science, Graduate School of Science, Nagoya University Furo-cho, Chikusa-ku, Nagoya 464-8602, Japan
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69
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Miura S, Davis S, Klingensmith J, Mishina Y. BMP signaling in the epiblast is required for proper recruitment of the prospective paraxial mesoderm and development of the somites. Development 2006; 133:3767-75. [PMID: 16943278 DOI: 10.1242/dev.02552] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Bmpr1a encodes the BMP type IA receptor for bone morphogenetic proteins (BMPs), including 2 and 4. Here, we use mosaic inactivation of Bmpr1a in the epiblast of the mouse embryo (Bmpr-MORE embryos) to assess functions of this gene in mesoderm development. Unlike Bmpr1a-null embryos, which fail to gastrulate, Bmpr-MORE embryos initiate gastrulation, but the recruitment of prospective paraxial mesoderm cells to the primitive streak is delayed. This delay causes a more proximal distribution of cells with paraxial mesoderm character within the primitive streak, resulting in a lateral expansion of somitic mesoderm to form multiple columns. Inhibition of FGF signaling restores the normal timing of recruitment of prospective paraxial mesoderm and partially rescues the development of somites. This suggests that BMP and FGF signaling function antagonistically during paraxial mesoderm development.
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MESH Headings
- Animals
- Body Patterning/genetics
- Bone Morphogenetic Protein Receptors, Type I/antagonists & inhibitors
- Bone Morphogenetic Protein Receptors, Type I/genetics
- Bone Morphogenetic Protein Receptors, Type I/physiology
- Bone Morphogenetic Proteins/physiology
- Embryonic Development/genetics
- Fibroblast Growth Factors/antagonists & inhibitors
- Fibroblast Growth Factors/genetics
- Fibroblast Growth Factors/physiology
- Mesoderm/cytology
- Mesoderm/physiology
- Mice
- Mice, Mutant Strains
- Receptor, Fibroblast Growth Factor, Type 1/antagonists & inhibitors
- Receptor, Fibroblast Growth Factor, Type 1/genetics
- Receptor, Fibroblast Growth Factor, Type 1/physiology
- Signal Transduction/genetics
- Somites/cytology
- Somites/physiology
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Affiliation(s)
- Shigeto Miura
- Laboratory of Reproductive and Developmental Toxicology, National Institute of Environmental Health Sciences, MD C4-10, C458, Research Triangle Park, NC 27709, USA
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70
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Abstract
The fossil record indicates that cypriniform fishes, a group including the zebrafish, lost oral teeth over 50 million years ago. Despite subsequent diversification of feeding modes, no cypriniform has regained oral teeth, suggesting the zebrafish as a model for studying the developmental genetic basis of evolutionary constraint. To investigate the mechanism of cypriniform tooth loss, we compared the oral expression of seven genes whose mammalian orthologs are involved in tooth initiation in the zebrafish and the Mexican tetra, Astyanax mexicanus, a related species retaining oral teeth. The most significant difference we found was an absence in zebrafish oral epithelium of expression of dlx2a and dlx2b, transcription factors that are expressed in early Astyanax odontogenic epithelium. Analysis of orthologous genes in the Japanese medaka (Oryzias latipes) and a catfish (Synodontis multipunctatus) suggests that expression was lost in cypriniforms, rather than gained in Astyanax. Treatment of Astyanax with an inhibitor of Fibroblast growth factor (Fgf) signaling produced a partial phenocopy of the zebrafish oral region, in that oral teeth, and expression of dlx2a and dlx2b, were lost, whereas shh and pitx2, genes whose expression is present in zebrafish oral epithelium, were unaffected. We hypothesize that a loss of Fgf signaling to oral epithelium was associated with cypriniform tooth loss.
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Affiliation(s)
- David W Stock
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO 80309-0334, USA.
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71
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Cuevas P, Díaz-González D, Sánchez I, Lozano RM, Giménez-Gallego G, Dujovny M. Dobesilate inhibits the activation of signal transducer and activator of transcription 3, and the expression of cyclin D1 and bcl-XL in glioma cells. Neurol Res 2006; 28:127-30. [PMID: 16551428 DOI: 10.1179/016164106x97982] [Citation(s) in RCA: 16] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
OBJECTIVES Because fibroblast growth factor (FGF) causes the intracellular accumulation of activated signal transducer and activator of transcription 3 (STAT3), we assessed whether dobesilate, a synthetic FGF inhibitor that has been reported to show antiproliferative and proapoptotic activities in glioma cell cultures, down-regulates the STAT3 signaling pathway in growing cultures of those cells. Because STAT3 signaling pathway plays pleiotropic roles in tumor proliferation, maintenance of STAT3 in its inactive state may prevent glioma growth and spreading. METHODS Rat glioma C6 cells were treated with dobesilate and cultures were evaluated immunocytochemically for STAT3 activation and enhancement of the expression rate of cyclin D1 and bcl-XL. RESULTS Dobesilate abrogates the accumulation of activated STAT3 in glioma cells. The decrease in the intracellular levels of activated STAT3 by the dobesilate treatment runs parallel with a significant attenuation of cyclin D1 and bcl-XL expression. CONCLUSION Treatment with inhibitors of FGF down-regulates the STAT3 signaling pathway. These alterations could be correlated to the already observed inhibition of cell proliferation and promotion of apoptosis in glioma cell cultures by dobesilate. The reported results may open new avenues for developing new treatments against these tumors.
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Affiliation(s)
- P Cuevas
- Departamento de Investigación, Hospital Universitario Ramón y Cajal, Universidad de Alcalá de Henares, Madrid, Spain.
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72
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Katoh Y, Katoh M. FGF signaling inhibitor, SPRY4, is evolutionarily conserved target of WNT signaling pathway in progenitor cells. Int J Mol Med 2006; 17:529-32. [PMID: 16465403] [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: 05/06/2023] Open
Abstract
WNT, FGF and Hedgehog signaling pathways network together during embryogenesis, tissue regeneration, and carcinogenesis. FGF16, FGF18, and FGF20 genes are targets of WNT-mediated TCF/LEF-beta-catenin-BCL9/BCL9L-PYGO transcriptional complex. SPROUTY (SPRY) and SPRED family genes encode inhibitors for receptor tyrosine kinase signaling cascades, such as those of FGF receptor family members and EGF receptor family members. Here, transcriptional regulation of SPRY1, SPRY2, SPRY3, SPRY4, SPRED1, SPRED2, and SPRED3 genes by WNT/beta-catenin signaling cascade was investigated by using bioinformatics and human intelligence (humint). Because double TCF/LEF-binding sites were identified within the 5'-promoter region of human SPRY4 gene, comparative genomics analyses on SPRY4 orthologs were further performed. SPRY4-FGF1 locus at human chromosome 5q31.3 and FGF2-NUDT6-SPATA5-SPRY1 locus at human chromosome 4q27-q28.1 were paralogous regions within the human genome. Chimpanzee SPRY4 gene was identified within NW_107083.1 genome sequence. Human, chimpanzee, rat and mouse SPRY4 orthologs, consisting of three exons, were well conserved. SPRY4 gene was identified as the evolutionarily conserved target of WNT/beta-catenin signaling pathway based on the conservation of double TCF/LEF-binding sites within 5'-promoter region of mammalian SPRY4 orthologs. Human SPRY4 mRNA was expressed in embryonic stem (ES) cells, brain, pancreatic islet, colon cancer, head and neck tumor, melanoma, and pancreatic cancer. WNT signaling activation in progenitor cells leads to the growth regulation of progenitor cells themselves through SPRY4 induction, and also to the growth stimulation of proliferating cells through FGF secretion. Epigenetic silencing and loss-of-function mutations of SPRY4 gene in progenitor cells could lead to carcinogenesis. SPRY4 is the pharmacogenomics target in the fields of oncology and regenerative medicine.
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73
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Luesch H, Chanda SK, Raya RM, DeJesus PD, Orth AP, Walker JR, Izpisúa Belmonte JC, Schultz PG. A functional genomics approach to the mode of action of apratoxin A. Nat Chem Biol 2006; 2:158-67. [PMID: 16474387 DOI: 10.1038/nchembio769] [Citation(s) in RCA: 114] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2005] [Accepted: 01/17/2006] [Indexed: 11/09/2022]
Abstract
The cyanobacterial metabolite apratoxin A (1) demonstrates potent cytotoxicity against tumor cell lines by a hitherto unknown mechanism. We have used functional genomics to elucidate the molecular basis for this activity. Gene expression profiling and DNA content analysis showed that apratoxin A induces G1-phase cell cycle arrest and apoptosis. Cell-based functional assays with a genome-wide collection of expression cDNAs showed that ectopic induction of fibroblast growth factor receptor (FGFR) signaling attenuates the apoptotic activity of apratoxin A. This natural product inhibited phosphorylation and activation of STAT3, a downstream effector of FGFR signaling. It also caused defects in FGF-dependent processes during zebrafish development, with concomitant reductions in expression levels of the FGF target gene mkp3. We conclude that apratoxin A mediates its antiproliferative activity through the induction of G1 cell cycle arrest and an apoptotic cascade, which is at least partially initiated through antagonism of FGF signaling via STAT3.
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Affiliation(s)
- Hendrik Luesch
- Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA.
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74
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Tomlinson DC, L'Hôte CG, Kennedy W, Pitt E, Knowles MA. Alternative splicing of fibroblast growth factor receptor 3 produces a secreted isoform that inhibits fibroblast growth factor-induced proliferation and is repressed in urothelial carcinoma cell lines. Cancer Res 2006; 65:10441-9. [PMID: 16288035 DOI: 10.1158/0008-5472.can-05-1718] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [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: 11/16/2022]
Abstract
Fibroblast growth factor receptors (FGFRs) are a family of receptor tyrosine kinases that play key roles in proliferation, differentiation, and tumorigenesis. FGFR3 was identified as the major family member expressed in both normal human urothelium and cultured normal human urothelial (NHU) cells and was expressed as the IIIb isoform. We also identified a splice variant, FGFR3 Delta8-10, lacking exons encoding the COOH-terminal half of immunoglobulin-like domain III and the transmembrane domain. Previous reports have assumed that this is a cancer-specific splice variant. We showed that FGFR3 Delta8-10 is a normal transcript in NHU cells and is translated, N-glycosylated, and secreted. Primary urothelium expressed high levels of FGFR3 transcripts. In culture, levels were reduced in actively proliferating cells but increased at confluence and as cells approached senescence. Cells overexpressing FGFR3 IIIb showed FGF1-induced proliferation, which was inhibited by the addition of FGFR3 Delta8-10. In bladder tumor cell lines derived from aggressive carcinomas, there were significant alterations in the relative expression of isoforms including an overall decrease in the proportion of FGFR3 Delta8-10 and predominant expression of FGFR3 IIIc in some cases. In summary, alternative splicing of FGFR3 IIIb in NHU cells represents a normal mechanism to generate a transcript that regulates proliferation and in bladder cancer, the ratio of FGFR3 isoforms is significantly altered.
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MESH Headings
- Aged
- Aged, 80 and over
- Alternative Splicing
- Base Sequence
- Carcinoma, Renal Cell/genetics
- Carcinoma, Renal Cell/metabolism
- Cell Line, Tumor
- Cloning, Molecular
- Female
- Fibroblast Growth Factors/antagonists & inhibitors
- Glycosylation
- Humans
- Kidney Neoplasms/genetics
- Kidney Neoplasms/metabolism
- Male
- Middle Aged
- Molecular Sequence Data
- Protein Isoforms
- RNA, Messenger/biosynthesis
- RNA, Messenger/genetics
- Receptor, Fibroblast Growth Factor, Type 3/biosynthesis
- Receptor, Fibroblast Growth Factor, Type 3/genetics
- Receptor, Fibroblast Growth Factor, Type 3/metabolism
- Urinary Bladder Neoplasms/genetics
- Urinary Bladder Neoplasms/metabolism
- Urologic Neoplasms/genetics
- Urologic Neoplasms/metabolism
- Urothelium/metabolism
- Urothelium/pathology
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Affiliation(s)
- Darren C Tomlinson
- Cancer Research UK Clinical Centre, St. James's University Hospital, Leeds, United Kingdom
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75
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Wu CS, Lan CCE, Chiou MH, Yu HS. Basic Fibroblast Growth Factor Promotes Melanocyte Migration via Increased Expression of p125FAK on Melanocytes. Acta Derm Venereol 2006; 86:498-502. [PMID: 17106595 DOI: 10.2340/00015555-0161] [Citation(s) in RCA: 23] [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: 11/16/2022] Open
Abstract
Vitiligo is an acquired pigmentary disorder characterized by depigmentation of skin and hair. Melanocyte migration is an important event in re-pigmentation of vitiligo. We have demonstrated that narrow-band ultraviolet B (UVB) irradiation stimulated cultured keratinocytes to release a significant amount of basic fibroblast growth factor (bFGF). Furthermore, narrow-band UVB enhanced migration of melanocytes via increased expression of phosphorylated focal adhesion kinase (p125(FAK)) on melanocytes. The aim of this study was to investigate the effect of recombinant human bFGF (rhbFGF) on melanocyte migration. The relationship between the expression of p125(FAK) and melanocyte migration induced by rhbFGF was also studied. Our results demonstrated that rhbFGF significantly enhanced migration of melanocytes and p125(FAK) expression on melanocytes. Herbimycin A, a potent p125(FAK) inhibitor, effectively abolished rhbFGF-induced melanocyte migration. The combined results indicated that p125(FAK) plays an important role in the signal transduction pathway of melanocyte migration induced by bFGF.
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Affiliation(s)
- Ching-Shuang Wu
- Faculty of Biomedical Laboratory Science, Kaohsiung Medical University Hospital, Taiwan
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76
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Sun Z, Zhao J, Zhang Y, Meng A. Sp5l is a mediator of Fgf signals in anteroposterior patterning of the neuroectoderm in zebrafish embryo. Dev Dyn 2006; 235:2999-3006. [PMID: 16958103 DOI: 10.1002/dvdy.20945] [Citation(s) in RCA: 7] [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: 01/21/2023] Open
Abstract
The neuroectoderm is patterned along the anterior-posterior axis in vertebrate embryos. Fgf signals are required to induce the posterior neuroectodermal fates, but they repress the anterior fate. Sp5l/Spr2, an Sp1-like transcription factor family member, has been shown to be required for development of mesoderm and posterior neuroectoderm. We demonstrate here that repression of the anterior neuroectodermal markers fez and otx1 by fgf17b or fgf3 coincides with induction of sp5l in the anterior neuroectoderm, and that this repression is efficiently rescued by simultaneous sp5l knockdown. On the other hand, sp5l knockdown is able to inhibit inductive activity of ectopic Fgf signals on the expression of the posterior neuroectodermal markers gbx2, hoxb1b, and krox20. Furthermore, effect of overexpression of a dominant negative Fgf receptor on anteroposterior patterning of the neuroectoderm is rescued by sp5l overexpression. Taken together, these data suggest that sp5l mediates the functions of Fgf signals in anteroposterior patterning of the neuroectoderm during zebrafish embryogenesis.
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Affiliation(s)
- Zhihui Sun
- State Key Laboratory of Biomembrane and Membrane Biotechnology, Department of Biological Sciences and Biotechnology, Tsinghua University, Beijing, China
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77
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Cuevas P, Arrazola JM. Therapeutic response of rosacea to dobesilate. Eur J Med Res 2005; 10:454-6. [PMID: 16287608] [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: 05/05/2023] Open
Abstract
Despite an incomplete understanding of the pathogenesis of rosacea, therapeutic modalities continue to expand. The principal subtype of rosacea includes erythematotelangiestatic rosacea, which is characterized by uncontrolled angiogenesis. Angiogenic growth factors such as fibroblast growth factors (FGF) and vascular endothelial growth factor (VEGF) are currently targets of intense effort to inhibit deregulated blood vessel formation in diseases such as cancer. Here we report a 33-years-old woman with erythematotelangestatic rosacea who responds to a daily treatment of topically applied dobesilate, an inhibitor of FGF, with an improvement in erythema and telangectasia after two weeks. Thus, dobesilate might be useful in the treatment of rosacea and other diseases that depend on pathologic angiogenesis.
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Affiliation(s)
- Pedro Cuevas
- Department of Research, Hospital Ramón y Cajal, Madrid, Spain.
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78
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Ørskov C, Hartmann B, Poulsen SS, Thulesen J, Hare KJ, Holst JJ. GLP-2 stimulates colonic growth via KGF, released by subepithelial myofibroblasts with GLP-2 receptors. ACTA ACUST UNITED AC 2005; 124:105-12. [PMID: 15544847 DOI: 10.1016/j.regpep.2004.07.009] [Citation(s) in RCA: 161] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2004] [Revised: 06/22/2004] [Accepted: 07/01/2004] [Indexed: 12/17/2022]
Abstract
BACKGROUND Glucagon-like peptide-2 is thought to act as a growth factor for the gut, but the localization of the GLP-2 receptor and mechanism of action on epithelial growth is unclear. METHODS AND RESULTS We found glucagon-like peptide-2 (GLP-2) receptors mainly on subepithelial myofibroblasts in rat, mouse, marmoset and human small and large intestine by immunohistochemistry and in situ hybridisation. By double labelling we found that these GLP-2 receptor immunoreactive cells also produce smooth muscle actin and keratinocyte growth factor (KGF). By subcutaneous infusion of either GLP-2 alone, GLP-2 plus KGF antibody, KGF antibody alone or saline in mice, we found that KGF antibody abolished the growth promoting effect of GLP-2 in the large intestine, but not in the small intestine. CONCLUSIONS Our findings suggest that GLP-2 in the gut acts by activating receptors on the subepithelial myofibroblasts, causing the release of growth factors, which in turn stimulate intestinal growth.
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Affiliation(s)
- Cathrine Ørskov
- Department of Medical Anatomy, The Panum Institute, University of Copenhagen, Blegdamsvej 3c, Copenhagen DK-2200, Denmark.
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79
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Casanovas O, Hicklin DJ, Bergers G, Hanahan D. Drug resistance by evasion of antiangiogenic targeting of VEGF signaling in late-stage pancreatic islet tumors. Cancer Cell 2005; 8:299-309. [PMID: 16226705 DOI: 10.1016/j.ccr.2005.09.005] [Citation(s) in RCA: 1231] [Impact Index Per Article: 64.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2005] [Revised: 09/06/2005] [Accepted: 09/23/2005] [Indexed: 01/13/2023]
Abstract
Function-blocking antibodies to VEGF receptors R1 and R2 were used to probe their roles in controlling angiogenesis in a mouse model of pancreatic islet carcinogenesis. Inhibition of VEGFR2 but not VEGFR1 markedly disrupted angiogenic switching, persistent angiogenesis, and initial tumor growth. In late-stage tumors, phenotypic resistance to VEGFR2 blockade emerged, as tumors regrew during treatment after an initial period of growth suppression. This resistance to VEGF blockade involves reactivation of tumor angiogenesis, independent of VEGF and associated with hypoxia-mediated induction of other proangiogenic factors, including members of the FGF family. These other proangiogenic signals are functionally implicated in the revascularization and regrowth of tumors in the evasion phase, as FGF blockade impairs progression in the face of VEGF inhibition.
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Affiliation(s)
- Oriol Casanovas
- Department of Biochemistry and Biophysics, Comprehensive Cancer Center, and Diabetes Center, University of California, San Francisco, San Francisco, California 94143, USA
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80
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Laschke MW, Elitzsch A, Vollmar B, Vajkoczy P, Menger MD. Combined inhibition of vascular endothelial growth factor (VEGF), fibroblast growth factor and platelet-derived growth factor, but not inhibition of VEGF alone, effectively suppresses angiogenesis and vessel maturation in endometriotic lesions. Hum Reprod 2005; 21:262-8. [PMID: 16172144 DOI: 10.1093/humrep/dei308] [Citation(s) in RCA: 132] [Impact Index Per Article: 6.9] [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: 11/12/2022] Open
Abstract
BACKGROUND Angiogenesis represents the crucial step in the pathogenesis of endometriosis, because endometriotic lesions require neovascularization to establish, proliferate and invade inside the peritoneal cavity. To elucidate the role of angiogenic factors, we investigated in vivo whether blockade of vascular endothelial growth factor (VEGF), fibroblast growth factor (FGF), and platelet-derived growth factor (PDGF) affects angiogenesis of ectopic endometrium. METHODS Mechanically isolated endometrial fragments were transplanted into the dorsal skinfold chamber of hormonally synchronized hamsters. Subsequently, we analysed the effect of the VEGF inhibitor SU5416 and the combined VEGF, FGF and PDGF inhibitor SU6668 on angiogenesis of the ectopic endometrium over a time-period of 14 days using intravital fluorescence microscopy. RESULTS Selective blockade of VEGF resulted in a slight reduction of microvessel density when compared to control animals. In contrast, combined inhibition of all three growth factors significantly suppressed angiogenesis of endometrial grafts, as indicated by a reduced size of the microvascular network and a decreased microvessel density. This was caused by an inhibition of blood vessel maturation. CONCLUSIONS Vascularization of endometriotic lesions is not solely driven by VEGF, but depends on the cross-talk between VEGF, FGF and PDGF. Thus, the combined inhibition of these growth factors may represent a novel therapeutic strategy in the treatment of endometriosis.
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Affiliation(s)
- M W Laschke
- Institute for Clinical & Experimental Surgery, University of Saarland, 66421 Homburg/Saar, Germany.
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81
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Cuevas P, Arrazola JM. Dobesilate in the treatment of plaque psoriasis. Eur J Med Res 2005; 10:373-6. [PMID: 16183548] [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: 05/04/2023] Open
Abstract
Fibroblast growth factor (FGF)-mediated pathways participate in many of the cellular events implicated in the pathogenesis of psoriasis. Thus, targeting FGF signals may be potentially therapeutic in the treatment of psoriasis. We report for the first time on a 43-year-old man with chronic-type plaque psoriasis with a daily topical treatment of dobesilate, a new FGF inhibitor. As early as at day 14, the patient had cleared or achieved excellent improvement of psoriatic skin lesions. Topical dobesilate offers the potential for treatment of plaque psoriasis without atrophy or other local side effects associated with the use of topical corticosteroids.
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Affiliation(s)
- Pedro Cuevas
- Servicio de Histologia, Departamento de Investigacion, Hospital Ramon y Cajal, Ctra. de Colmenar, km. 9.100, E-28034-Madrid, Spain.
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82
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Lin W, Jing N, Basson MA, Dierich A, Licht J, Ang SL. Synergistic activity of Sef and Sprouty proteins in regulating the expression of Gbx2 in the mid-hindbrain region. Genesis 2005; 41:110-5. [PMID: 15729686 DOI: 10.1002/gene.20103] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Sef and Sprouty proteins function as feedback antagonists of fibroblast growth factor (Fgf) signaling in zebrafish embryos. To study the role of Sef in mice, we generated Sef homozygous mutant animals. These animals are viable and show normal expression of mid-hindbrain genes at embryonic days 8.5 and 9.5. To investigate the possibility of functional synergism between Sef and Sprouty proteins, we electroporated Sprouty2(Y55A), which functions in a dominant-negative manner in tissue culture cells into the mid-hindbrain region of wildtype and Sef mutant embryos. The expression pattern of Gbx2, a downstream target of Fgf signaling, was expanded or shifted in electroporated embryos, and this effect was significantly enhanced in the Sef mutant background. Altogether, our results demonstrate that Sef and Sproutys function synergistically to regulate Gbx2 expression in the anterior hindbrain.
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Affiliation(s)
- Wei Lin
- Medical Research Council, National Institute for Medical Research, London, UK
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83
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Shim K, Minowada G, Coling DE, Martin GR. Sprouty2, a mouse deafness gene, regulates cell fate decisions in the auditory sensory epithelium by antagonizing FGF signaling. Dev Cell 2005; 8:553-64. [PMID: 15809037 DOI: 10.1016/j.devcel.2005.02.009] [Citation(s) in RCA: 202] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2005] [Revised: 02/11/2005] [Accepted: 02/22/2005] [Indexed: 11/20/2022]
Abstract
The auditory sensory epithelium (organ of Corti), where sound waves are converted to electrical signals, comprises a highly ordered array of sensory receptor (hair) cells and nonsensory supporting cells. Here, we report that Sprouty2, which encodes a negative regulator of signaling via receptor tyrosine kinases, is required for normal hearing in mice, and that lack of SPRY2 results in dramatic perturbations in organ of Corti cytoarchitecture: instead of two pillar cells, there are three, resulting in the formation of an ectopic tunnel of Corti. We demonstrate that these effects are due to a postnatal cell fate transformation of a Deiters' cell into a pillar cell. Both this cell fate change and hearing loss can be partially rescued by reducing Fgf8 gene dosage in Spry2 null mutant mice. Our results provide evidence that antagonism of FGF signaling by SPRY2 is essential for establishing the cytoarchitecture of the organ of Corti and for hearing.
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Affiliation(s)
- Katherine Shim
- Department of Anatomy and Program in Developmental Biology, School of Medicine, University of California, San Francisco, California 94143, USA
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84
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Ramsden JD, Buchanan MA, Egginton S, Watkinson JC, Mautner V, Eggo MC. Complete inhibition of goiter in mice requires combined gene therapy modification of angiopoietin, vascular endothelial growth factor, and fibroblast growth factor signaling. Endocrinology 2005; 146:2895-902. [PMID: 15817662 DOI: 10.1210/en.2005-0168] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
In goiter, increased expression of growth factors and their receptors occurs. We have inhibited the action of some of these growth factors, alone and in combination, to determine which are important in goitrogenesis. Recombinant adenovirus vectors (RAds) expressing truncated, secreted forms of human Tie2 (RAd-sTie2) and vascular endothelial growth factor receptor 1 (RAd-sVEGFR1) or a truncated, dominant-negative fibroblast growth factor receptor 1 (RAdDN-FGFR1) were used. Goiters in mice were induced by feeding an iodide-deficient diet, containing methimazole and sodium perchlorate. RAds were administered to mice simultaneously with the goitrogenic regimen, which was continued for 14 d. RAd treatment did not significantly affect increases in TSH or reductions in thyroid hormone or thyroid hyperactivity seen in goitrogen-treated controls mice, suggesting no effect on pituitary or thyroid responses to hypothyroidism. In control goiters, a 4-fold increase in vascular volume accompanied a 2-fold increase in thyroid mass. Complete inhibition of these increases was found when animals were treated with the three RAds in combination. In thyroids from three RAd-treated animals, there was marked, significant inhibition of Tie2, FGFR1, VEGFR1, FGF-2, and VEGF expression, compared with control goiters. When used individually, RAdDN-FGFR1 partially prevented goiter and RAd-sVEGFR1 partially reduced vascular volume. Their effects were not additive. RAd-sTie2 did not reduce goiter mass or vascular volume when used alone but was essential for complete goiter inhibition. VEGF and VEGFR1 expression was reduced in these thyroids. Limitation of physiologic organ growth is complex, requiring inhibition of multiple, interdependent growth factor axes.
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Affiliation(s)
- James D Ramsden
- Division of Medical Sciences, University of Birmingham, Birmingham B15 2TT, UK
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85
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McDaid HM, Lopez-Barcons L, Grossman A, Lia M, Keller S, Pérez-Soler R, Horwitz SB. Enhancement of the therapeutic efficacy of taxol by the mitogen-activated protein kinase kinase inhibitor CI-1040 in nude mice bearing human heterotransplants. Cancer Res 2005; 65:2854-60. [PMID: 15805287 DOI: 10.1158/0008-5472.can-04-4391] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Taxol may contribute to intrinsic chemoresistance by activating the mitogen-activated protein kinase kinase (MEK)/extracellular signal-regulated kinase (ERK) cytoprotective pathway in human cancer cell lines and tumors. We have previously shown additivity between Taxol and the MEK inhibitor, U0126 in human cancer cell lines. Here, the combination of Taxol with an orally bioavailable MEK inhibitor, CI-1040, was evaluated in human lung tumors heterotransplanted into nude mice. Unlike xenograft models that are derived from cells with multiple genetic alterations due to prolonged passage, heterotransplanted tumor models are more clinically relevant. Combined treatment with both drugs resulted in inhibition of tumor growth in all models and tumor regressions in three of four models tested, supporting our previous observation that Taxol's efficacy is potentiated by MEK inhibition. Concurrent administration was superior to intermittent dosing. Pharmacodynamic assessments of tumors indicated that suppression of MEK was associated with induction of S473 phosphorylated Akt and reduced proliferation in the combination groups relative to single agents, in addition to suppression of fibroblast growth factor-mediated angiogenesis and reduced expression of vascular endothelial growth factor. These findings are significant and indicate that this combination may have broad therapeutic applications in a diverse range of lung tumors with different intrinsic chemosensitivities.
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Affiliation(s)
- Hayley M McDaid
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, New York 10461, USA.
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86
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Yoshioka H, Ishimaru Y, Sugiyama N, Tsunekawa N, Noce T, Kasahara M, Morohashi KI. Mesonephric FGF signaling is associated with the development of sexually indifferent gonadal primordium in chick embryos. Dev Biol 2005; 280:150-61. [PMID: 15766755 DOI: 10.1016/j.ydbio.2005.01.011] [Citation(s) in RCA: 24] [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] [Received: 10/27/2004] [Revised: 01/11/2005] [Accepted: 01/12/2005] [Indexed: 11/18/2022]
Abstract
The gonad as well as the reproductive tracts, kidney, and adrenal cortex are derived from the intermediate mesoderm. In addition, the intermediate mesoderm forms the mesonephros. Although the mesonephros is the source of certain testicular cell types, its contribution to gonad formation through expression of growth factors is largely unknown. Here, we examined the expression profiles of FGF9 in the developing mesonephros of chick embryos at sexually indifferent stages, and found that the expression domain is adjacent to the gonadal primordium. Moreover, FGFR3 (FGF receptor 3) showed a strong expression in the gonadal primordium. Next, we examined the functions of FGF signal during gonadal development with misexpressed FGF9. Interestingly, misexpression of FGF9 led to gonadal expansion through stimulation of cell proliferation. In contrast, treatment with a chemical inhibitor for FGFR decreased cell proliferation and resulted in reduction of the gonadal size. Simultaneously, the treatment resulted in reduction of gonadal marker gene expression. Our study demonstrated that FGF expressed in the developing mesonephros is involved in the development of the gonad at the sexually indifferent stages through stimulation of gonadal cell proliferation and gonadal marker gene expression.
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Affiliation(s)
- Hidefumi Yoshioka
- Department of Natural Sciences, Hyogo University of Teacher Education, 942-1, Yashiro-cho, Kato Gun, Hyogo 673-1494, Japan
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87
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Mueller AM, Pedré X, Kleiter I, Hornberg M, Steinbrecher A, Giegerich G. Targeting fibroblast growth factor-inducible-14 signaling protects from chronic relapsing experimental autoimmune encephalomyelitis. J Neuroimmunol 2005; 159:55-65. [PMID: 15652403 DOI: 10.1016/j.jneuroim.2004.10.001] [Citation(s) in RCA: 35] [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] [Received: 04/30/2004] [Revised: 08/04/2004] [Accepted: 10/04/2004] [Indexed: 11/24/2022]
Abstract
The TNF-related weak inducer of apoptosis (TWEAK) is a TNF family member mediating proinflammatory effects by its receptor fibroblast growth factor-inducible-14 (Fn14). We studied the role of TWEAK/Fn14 in experimental autoimmune encephalomyelitis (EAE) by protein vaccination with TWEAK and Fn14 and recombinant TWEAK-DNA, respectively. TWEAK-DNA vaccination worsened the clinical course of EAE and increased central nervous system (CNS) inflammation. TWEAK increased the secretion of CCL2 [monocyte chemotactic protein-1 (MCP-1)] by CNS endothelial cells and astrocytes in vitro, suggesting CCL2 as a critical mediator of TWEAKs proinflammatory effects. Vaccination with the extracellular domain of TWEAK or with Fn14 resulted in the induction of specific inhibitory antibodies and an amelioration of EAE signs in two different models in rats and mice. Spinal cord inflammatory infiltrates were significantly diminished. Purified IgG from TWEAK- or Fn14-vaccinated rats prevented TWEAK-induced production of CCL2 by endothelial cells. Blocking Fn14 signaling represents a novel approach with potential for the treatment of CNS autoimmunity.
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MESH Headings
- Animals
- Antibodies, Blocking/biosynthesis
- Antibodies, Blocking/pharmacology
- Apoptosis
- Apoptosis Regulatory Proteins
- Cell Movement/immunology
- Cell Proliferation
- Chemokines/metabolism
- Chronic Disease
- Cytokine TWEAK
- Encephalomyelitis, Autoimmune, Experimental/immunology
- Encephalomyelitis, Autoimmune, Experimental/pathology
- Encephalomyelitis, Autoimmune, Experimental/prevention & control
- Female
- Fibroblast Growth Factors/antagonists & inhibitors
- Fibroblast Growth Factors/genetics
- Fibroblast Growth Factors/immunology
- Fibroblast Growth Factors/physiology
- Immune Sera/biosynthesis
- Immune Sera/pharmacology
- Ligands
- Lymph Nodes/immunology
- Lymph Nodes/pathology
- Lymphocyte Count
- Membrane Proteins/adverse effects
- Membrane Proteins/genetics
- Membrane Proteins/immunology
- Mice
- Molecular Sequence Data
- Myelin Proteins
- Myelin Proteolipid Protein/antagonists & inhibitors
- Myelin Proteolipid Protein/toxicity
- Myelin-Associated Glycoprotein/antagonists & inhibitors
- Myelin-Associated Glycoprotein/toxicity
- Myelin-Oligodendrocyte Glycoprotein
- Rats
- Recombinant Fusion Proteins/administration & dosage
- Recombinant Fusion Proteins/adverse effects
- Recombinant Fusion Proteins/genetics
- Recombinant Fusion Proteins/immunology
- Secondary Prevention
- Severity of Illness Index
- Signal Transduction/immunology
- T-Lymphocytes/pathology
- Tumor Necrosis Factors/adverse effects
- Tumor Necrosis Factors/genetics
- Tumor Necrosis Factors/immunology
- Vaccines, DNA/administration & dosage
- Vaccines, DNA/adverse effects
- Vaccines, DNA/immunology
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Affiliation(s)
- A M Mueller
- Department of Neurology, University of Regensburg, Universitaetsstr. 84, 93053 Regensburg, Germany
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88
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Abstract
A dominant molecular explanation for neural induction is the 'default model', which proposes that the ectoderm is pre-programmed towards a neural fate, but is normally inhibited by endogenous BMPs. Although there is strong evidence favouring this in Xenopus, data from other organisms suggest more complexity, including an involvement of FGF and modulation of Wnt. However, it is generally believed that these additional signals also act by inhibiting BMPs. We have investigated whether BMP inhibition is necessary and/or sufficient for neural induction. In the chick, misexpression of BMP4 in the prospective neural plate inhibits the expression of definitive neural markers (Sox2 and late Sox3), but does not affect the early expression of Sox3, suggesting that BMP inhibition is required only as a late step during neural induction. Inhibition of BMP signalling by the potent antagonist Smad6, either alone or together with a dominant-negative BMP receptor, Chordin and/or Noggin in competent epiblast is not sufficient to induce expression of Sox2 directly, even in combination with FGF2, FGF3, FGF4 or FGF8 and/or antagonists of Wnt signalling. These results strongly suggest that BMP inhibition is not sufficient for neural induction in the chick embryo. To test this in Xenopus, Smad6 mRNA was injected into the A4 blastomere (which reliably contributes to epidermis but not to neural plate or its border) at the 32-cell stage: expression of neural markers (Sox3 and NCAM) is not induced. We propose that neural induction involves additional signalling events that remain to be identified.
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Affiliation(s)
- Claudia Linker
- Department of Anatomy and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK
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89
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Mukherjee A, Dong SS, Clemens T, Alvarez J, Serra R. Co-ordination of TGF-beta and FGF signaling pathways in bone organ cultures. Mech Dev 2004; 122:557-71. [PMID: 15804568 DOI: 10.1016/j.mod.2004.11.006] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2004] [Revised: 11/09/2004] [Accepted: 11/09/2004] [Indexed: 11/26/2022]
Abstract
Transforming growth factor-beta (TGF-beta) is known to regulate chondrocyte proliferation and hypertrophic differentiation in embryonic bone cultures by a perichondrium dependent mechanism. To begin to determine which factors in the perichondrium mediate the effects of TGF-beta, we studied the effect of Insulin-like Growth Factor-1 (IGF-I) and Fibroblast Growth Factors-2 and -18 (FGF2, FGF18) on metatarsal organ cultures. An increase in chondrocyte proliferation and hypertrophic differentiation was observed after treatment with IGF-I. A similar effect was seen after the perichondrium was stripped from the metatarsals suggesting IGF-I acts directly on the chondrocytes. Treatment with FGF-2 or FGF-18 resulted in a decrease in bone elongation as well as hypertrophic differentiation. Treatment also resulted in a decrease in BrdU incorporation into chondrocytes and an increase in BrdU incorporation in perichondrial cells, similar to what is seen after treatment with TGF-beta1. A similar effect was seen with FGF2 after the perichondrium was stripped suggesting that, unlike TGF-beta, FGF2 acts directly on chondrocytes to regulate proliferation and hypertrophic differentiation. To test the hypothesis that TGF-beta regulates IGF or FGF signaling, activation of the receptors was characterized after treatment with TGF-beta. Activation was measured as the level of tyrosine phosphorylation on the receptor. Treatment with TGF-beta for 24h did not alter the level of IGFR-I tyrosine phosphorylation. In contrast, treatment with TGF-beta resulted in and increase in tyrosine phosphorylation on FGFR3 without alterations in total FGFR3 levels. TGF-beta also stimulated expression of FGF18 mRNA in the cultures and the effects of TGF-beta on metatarsal development were blocked or partially blocked by pretreatment with FGF signaling inhibitors. The results suggest a model in which FGF through FGFR3 mediates some of the effects of TGF-beta on embryonic bone formation.
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Affiliation(s)
- Aditi Mukherjee
- Department of Pathology, University of Alabama, Birmingham, AL 35294-0005, USA
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90
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Abstract
Prostate cancer is the most common malignancy in men in the USA and the second leading cause of cancer deaths. Fibroblast growth factors (FGFs), including FGF1 (acidic FGF), FGF2 (basic FGF), FGF6 and FGF8 are all expressed at increased levels in prostate cancer as paracrine and/or autocrine growth factors for the prostate cancer cells. In addition, increased mobilization of FGFs from the extracellular matrix in cancer tissues can increase the availability of FGFs to cancer cells. Prostate cancer epithelial cells express all four types of FGF receptors (FGFR-1 to -4) at variable frequencies. Expression of FGFR-1 and FGFR-4 is most closely linked to prostate cancer progression, while the role of FGFR-2 remains controversial. Activation of FGF receptors can activate multiple signal transduction pathways including the phospholipase Cgamma, phosphatidyl inositol 3-kinase, mitogen-activated protein kinase and signal transducers and activators of transcription (STAT) pathways, all of which play a role in prostate cancer progression. Sprouty proteins can negatively regulate FGF signal transduction, potentially limiting the impact of FGF signaling in prostate cancer, but in a significant fraction of prostate cancers there is decreased expression of Sprouty1 mRNA and protein. The effects of increased FGF receptor signaling are wide ranging and involve both the cancer cells and surrounding stroma, including the vasculature. The net result of increased FGF signaling includes enhanced proliferation, resistance to cell death, increased motility and invasiveness, increased angiogenesis, enhanced metastasis, resistance to chemotherapy and radiation and androgen independence, all of which can enhance tumor progression and clinical aggressiveness. For this reason, the FGF signaling system it is an attractive therapeutic target, particularly since therapies targeting FGF receptors and/or FGF signaling can affect both the tumor cells directly and tumor angiogenesis. A number of approaches that could target FGF receptors and/or FGF receptor signaling in prostate cancer are currently being developed.
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Affiliation(s)
- B Kwabi-Addo
- Department of Pathology, Baylor College of Medicine and Michael E DeBakey Department of Veterans Affairs Medical Center, Houston, Texas 77030, USA.
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91
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Abstract
Myogenesis in vertebrate myocytes is promoted by activation of the phosphatidyl-inositol 3'-kinase (PI3 kinase) pathway and inhibited by fibroblast growth factor (FGF) signaling. We show that hyperactivation of the Caenorhabditis elegans FGF receptor, EGL-15, similarly inhibits the differentiation of the hermaphrodite sex muscles. Activation of the PI3 kinase signaling pathway can partially suppress this differentiation defect, mimicking the antagonistic relationship between these two pathways known to influence vertebrate myogenesis. When ectopically expressed in body wall muscle precursor cells, hyperactivated EGL-15 can also interfere with the proper development of the body wall musculature. Hyperactivation of EGL-15 has also revealed additional effects on a number of fundamental processes within the postembryonic muscle lineage, such as cell division polarity. These studies provide important in vivo insights into the contribution of FGF signaling events to myogenesis.
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Affiliation(s)
- Isaac E Sasson
- Yale University School of Medicine, Department of Genetics, I-354 SHM, PO Box 208005, New Haven, CT 06520-8005, USA
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92
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Abstract
Fibroblast growth factor (FGF) signaling is required for normal development of the vertebrate brain, including the isthmus and caudal regions of the hindbrain. Recent work in zebrafish has identified a requirement for the combination of fgf3 and fgf8 functions in specification of rhombomeres 5 and 6 (r5, r6), when evaluated at mid- and late somitogenesis stages. However, when examined earlier in development, during early somitogenesis stages, FGF8 alone is required to initiate r5 and r6 development. Both a mutation in fgf8 and injection of fgf8-targeted antisense morpholino-modified oligonucleotides result in suppression of genes normally expressed in r5 and r6 by the one- to two-somite stage. This expression recovers by the six-somite stage, and we propose that this recovery is a response to activation of fgf3 and to delayed accumulation of fgf8. These data demonstrate an early, nonredundant requirement for fgf8 function in hindbrain patterning.
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93
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Umemori H, Linhoff MW, Ornitz DM, Sanes JR. FGF22 and its close relatives are presynaptic organizing molecules in the mammalian brain. Cell 2004; 118:257-70. [PMID: 15260994 DOI: 10.1016/j.cell.2004.06.025] [Citation(s) in RCA: 185] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2004] [Revised: 05/28/2004] [Accepted: 06/01/2004] [Indexed: 01/06/2023]
Abstract
Target-derived cues promote local differentiation of axons into nerve terminals at sites of synaptic contact. Using clustering of synaptic vesicles in cultured neurons as an assay, we purified putative target-derived presynaptic organizing molecules from mouse brain and identified FGF22 as a major active species. FGF7 and FGF10, the closest relatives of FGF22, share this activity; other FGFs have distinct effects. FGF22 is expressed by cerebellar granule cells during the period when they receive synapses. Its receptor, FGFR2, is expressed by pontine and vestibular neurons when their axons (mossy fibers) are making synapses on granule cells. Neutralization of FGF7, -10, and -22 inhibits presynaptic differentiation of mossy fibers at sites of contact with granule cells in vivo. Inactivation of FGFR2 has similar effects. These results indicate that FGF22 and its relatives are presynaptic organizing molecules in the mammalian brain and suggest new functions for this family of signaling molecules.
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Affiliation(s)
- Hisashi Umemori
- Department of Anatomy and Neurobiology, Washington University Medical School, St. Louis, MO 63110, USA
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94
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Myers AP, Corson LB, Rossant J, Baker JC. Characterization of mouse Rsk4 as an inhibitor of fibroblast growth factor-RAS-extracellular signal-regulated kinase signaling. Mol Cell Biol 2004; 24:4255-66. [PMID: 15121846 PMCID: PMC400469 DOI: 10.1128/mcb.24.10.4255-4266.2004] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Receptor tyrosine kinase (RTK) signals regulate the specification of a varied array of tissue types by utilizing distinct modules of proteins to elicit diverse effects. The RSK proteins are part of the RTK signal transduction pathway and are thought to relay these signals by acting downstream of extracellular signal-regulated kinase (ERK). In this study we report the identification of ribosomal S6 kinase 4 (Rsk4) as an inhibitor of RTK signals. Among the RSK proteins, RTK inhibition is specific to RSK4 and, in accordance, is dependent upon a region of the RSK4 protein that is divergent from other RSK family members. We demonstrate that Rsk4 inhibits the transcriptional activation of specific targets of RTK signaling as well as the activation of ERK. Developmentally, Rsk4 is expressed in extraembryonic tissue, where RTK signals are known to have critical roles. Further examination of Rsk4 expression in the extraembryonic tissues demonstrates that its expression is inversely correlated with the presence of activated ERK 1/2. These studies demonstrate a new and divergent function for RSK4 and support a role for RSK proteins in the specification of RTK signals during early mouse development.
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Affiliation(s)
- Andrea Pomrehn Myers
- Department of Genetics, Stanford Medical School, Stanford, California 94305, USA
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95
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Abstract
OBJECTIVES Hyperbaric oxygen (HBO) has been used in the clinical setting to heal problem wounds, yet its direct effects on fibroblasts are not clear. The present study evaluates the effects of HBO on the growth and autocrine production of growth factors by fibroblasts grown in an in vitro, serum-free environment. METHODS Human dermal fibroblasts were propagated in serum-free media and subjected to daily 90-minute HBO treatments at 1.0, 1.5, 2.0, 2.5, and 3.0 atm of pressure for 7 consecutive days. Cell proliferation and growth-factor assays for basic fibroblast growth factor (bFGF), vascular endothelial growth factor (VEGF), and transforming growth factor beta1 (TGF-beta1) were performed on days 1, 3, 5, and 7. RESULTS On day 1, HBO inhibited growth of fibroblasts at all atmospheric pressures compared with control. By day 7, cell proliferation was significantly enhanced only in cells treated with 2.0-atm HBO compared with controls. Secretion of bFGF was significantly increased by HBO-treated fibroblasts on day 1; VEGF levels slightly increased with HBO treatment on day 1, but this effect was not statistically significant; TGF-beta1 levels were detectable on day 1 only for control and HBO-treated cells at 1.0 atm, and not detectable for any cell groups after day 1. CONCLUSIONS These results suggest that daily HBO treatment enhances the growth of fibroblasts when administered to a critical degree. Also, HBO appears to directly effect fibroblast production of autocrine growth factors on initial exposure. We postulate that fibroblasts possess the ability to respond to hyperoxia directly, which causes changes in cell signaling pathways involved in cellular proliferation and growth factor production.
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Affiliation(s)
- Thomas S Kang
- Wound Healing and Tissue Engineering Laboratory, Division of Otolaryngology -- Head and Neck Surgery, Stanford University School of Medicine, Stanford, Calif. 94305-5328, USA
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96
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Mason JM, Morrison DJ, Bassit B, Dimri M, Band H, Licht JD, Gross I. Tyrosine phosphorylation of Sprouty proteins regulates their ability to inhibit growth factor signaling: a dual feedback loop. Mol Biol Cell 2004; 15:2176-88. [PMID: 15004239 PMCID: PMC404014 DOI: 10.1091/mbc.e03-07-0503] [Citation(s) in RCA: 109] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2003] [Revised: 12/22/2003] [Accepted: 01/26/2004] [Indexed: 01/11/2023] Open
Abstract
Sprouty proteins are recently identified receptor tyrosine kinase (RTK) inhibitors potentially involved in many developmental processes. Here, we report that Sprouty proteins become tyrosine phosphorylated after growth factor treatment. We identified Tyr55 as a key residue for Sprouty2 phosphorylation and showed that phosphorylation was required for Sprouty2 to inhibit RTK signaling, because a mutant Sprouty2 lacking Tyr55 augmented signaling. We found that tyrosine phosphorylation of Sprouty2 affected neither its subcellular localization nor its interaction with Grb2, FRS2/SNT, or other Sprouty proteins. In contrast, Sprouty2 tyrosine phosphorylation was necessary for its binding to the Src homology 2-like domain of c-Cbl after fibroblast growth factor (FGF) stimulation. To determine whether c-Cbl was required for Sprouty2-dependent cellular events, Sprouty2 was introduced into c-Cbl-wild-type and -null fibroblasts. Sprouty2 efficiently inhibited FGF-induced phosphorylation of extracellular signal-regulated kinase 1/2 in c-Cbl-null fibroblasts, thus indicating that the FGF-dependent binding of c-Cbl to Sprouty2 was dispensable for its inhibitory activity. However, c-Cbl mediates polyubiquitylation/proteasomal degradation of Sprouty2 in response to FGF. Last, using Src-family pharmacological inhibitors and dominant-negative Src, we showed that a Src-like kinase was required for tyrosine phosphorylation of Sprouty2 by growth factors. Thus, these data highlight a novel negative and positive regulatory loop that allows for the controlled, homeostatic inhibition of RTK signaling.
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Affiliation(s)
- Jacqueline M Mason
- Division of Hematology/Oncology, Department of Medicine, Mount Sinai School of Medicine, New York, NY 10029, USA
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97
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Abstract
The keratinocyte growth factor receptor (KGFR) is a member of the fibroblast growth factor receptor (FGFR) superfamily. The proximal signaling molecules of FGFRs are much less characterized compared with other growth factor receptors. Using the yeast two-hybrid assay, we have identified ribosomal S6 kinase (RSK) to be a protein that associates with the cytoplasmic domain of the KGFR. The RSK family of kinases controls multiple cellular processes, and our studies for the first time show association between the KGFR and RSK. Using a lung-specific inducible transgenic system we have recently demonstrated protective effects of KGF on the lung epithelium and have demonstrated KGF-induced activation of the prosurvival Akt pathway both in vivo and in vitro. Here we show that a kinase inactive RSK mutant blocks KGF-induced Akt activation and KGF-mediated inhibition of caspase 3 activation in epithelial cells subjected to oxidative stress. It was recently shown that RSK2 recruits PDK1, the kinase responsible for both Akt and RSK activation. When viewed collectively, it appears that the association between the KGFR and RSK plays an important role in KGF-induced Akt activation and consequently in the protective effects of KGF on epithelial cells.
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Affiliation(s)
- Zhong-Zong Pan
- Department of Medical Oncology, Fox Chase Cancer Center, Philadelphia, Pennsylvania 19111, USA
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98
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Cha SW, Hwang YS, Chae JP, Lee SY, Lee HS, Daar I, Park MJ, Kim J. Inhibition of FGF signaling causes expansion of the endoderm in Xenopus. Biochem Biophys Res Commun 2004; 315:100-6. [PMID: 15013431 DOI: 10.1016/j.bbrc.2004.01.019] [Citation(s) in RCA: 13] [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] [Received: 12/01/2003] [Indexed: 02/08/2023]
Abstract
Fibroblast growth factor (FGF) is established as an initiator of signaling events critical for neurogenesis and mesoderm formation during early Xenopus embryogenesis. However, less is known about the role FGF signaling plays in endoderm specification. Here, we show for the first time that endoderm-specific genes are induced when FGF signaling is blocked in animal cap explants. This block of FGF signaling is also responsible for a significant enhancement of endodermal gene expression in animal cap explants that are injected with a dominant-negative BMP-4 receptor (DNBR) RNA or treated with activin, however, neural and mesoderm gene expression is diminished. Consistent with these results, the injection of dominant-negative FGF receptor (DNFR) RNA expands endodermal cell fate boundaries while FGF treatment dramatically reduces endoderm in whole embryos. Taken together, these results indicate that inhibition of FGF signaling promotes endoderm formation, whereas the presence of active FGF signaling is necessary for neurogenesis/mesoderm formation.
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Affiliation(s)
- Sang-Wook Cha
- Department of Anatomy, School of Medicine, Kyungpook National University, Daegu 700-422, Republic of Korea
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99
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Wang S, Ai X, Freeman SD, Pownall ME, Lu Q, Kessler DS, Emerson CP. QSulf1, a heparan sulfate 6-O-endosulfatase, inhibits fibroblast growth factor signaling in mesoderm induction and angiogenesis. Proc Natl Acad Sci U S A 2004; 101:4833-8. [PMID: 15051888 PMCID: PMC387334 DOI: 10.1073/pnas.0401028101] [Citation(s) in RCA: 159] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
The signaling activities of multiple developmental ligands require sulfated heparan sulfate (HS) proteoglycans as coreceptors. QSulf1 and its mammalian orthologs are cell surface HS 6-O-endosulfatases that are expressed in embryonic mesodermal and neural progenitors and promote Wnt signal transduction. In this study, we have investigated the function of QSulf1 in fibroblast growth factor (FGF) signaling, which requires 6-O-sulfated HS for FGF receptor (FGFR) dimerization and tyrosine kinase activation. Here, we report that QSulf1 inhibits FGF2- and FGF4-induced mesoderm formation in the Xenopus embryo and FGF-dependent angiogenesis in the chicken embryo through 6-O-desulfation of cell surface HS. QSulf1 regulates FGF signaling through inhibition of HS-mediated FGFR1 activation by interfering with FGF-HS-FGFR1 ternary complex formation. Furthermore, QSulf1 can produce enzymatically modified soluble heparin that acts as a potent inhibitor of FGF2-induced angiogenesis in the chicken embryo. QSulf1, therefore, has dual regulatory functions as a negative regulator of FGF signaling and a positive regulator of Wnt signaling. Therefore, QSulf1 provides another reagent to produce enzymatically modified heparin compounds, in vivo and in vitro, to modulate cellular signaling in stem cell-based therapies to promote tissue regeneration and in cancer therapies to control cell growth and block angiogenesis.
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Affiliation(s)
- Shouwen Wang
- Department of Cell and Developmental Biology, University of Pennsylvania Medical Center, Philadelphia, PA 19104, USA
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100
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Ito C, Saitoh Y, Fujita Y, Yamazaki Y, Imamura T, Oka S, Suzuki S. Decapeptide with fibroblast growth factor (FGF)-5 partial sequence inhibits hair growth suppressing activity of FGF-5. J Cell Physiol 2003; 197:272-83. [PMID: 14502567 DOI: 10.1002/jcp.10369] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [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]
Abstract
Earlier studies demonstrated that knock-out of fibroblast growth factor-5 gene (Fgf-5) prolonged anagen VI phase of hair cycle, resulting long hairs in the mice. We showed the activities on hair growth of the two Fgf-5 gene products, one of which, FGF-5 suppressed hair growth by inhibiting anagen proceeding and inducing the transition from anagen to catagen, and FGF-5S, a shorter polypeptide with FGF-5-antagonizing activity translated from alternatively spliced mRNA, suppressed this activity of FGF-5. As the results suggested that FGF-5 antagonist would increase hair growth, we synthesized various peptides having partial sequences of human FGF-5 and FGF-5S and determined their FGF-5 antagonist activity. Among them, a decapeptide designated P3 (95-VGIGFHLQIY-104) that aligns with receptor binding sites of FGF-1 and FGF-2 suppressed FGF-5-induced proliferation of BALB/3T3 A31 and NIH/3T3 murine fibroblasts, and FGF receptor-1c (FGFR-1c)-transfected Ba/F3 cell line (FR-Ba/F3 cells). IC50s of this peptide on these cell proliferations were 64, 28, 146 microM, respectively. On the other hand, IC50 of this peptide on binding of FGF-5 to the FGFR-1(IIIc)/Fc chimera was 483 microM. Examination in dorsal depilated mice revealed that the P3 peptide reduced the activity of FGF-5 to recover hair pigmentation and hair follicle lengths. The classification of histologically observed skin sections showed FGF-5-induced delations of anagen procedure had reduced by the P3 peptide. The anti-Ki67 antibody staining of hair follicles was inhibited by administration of FGF-5, and this inhibition by FGF-5 was recovered by administration of the P3 peptide. The P3 peptide alone did not affect hair follicle length and hair cell proliferation. These results indicate that the decapeptide antagonized FGF-5 activity in vivo, and reduced the inhibition of FGF-5 in hair growth, confirming that FGF-5 inhibitors are promising substances against hair loss and/or for promoting hair growth.
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Affiliation(s)
- Chikako Ito
- Institute for Biological Resources and Functions, National Institute of Advanced Industrial Science and Technology, Tsukuba, Japan
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