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Farrar WL, Ferris DK, Linnekin D. Haemopoietic growth factor regulation of protein kinases and genes associated with cell proliferation. Ciba Found Symp 2007; 148:127-37; discussion 137-44. [PMID: 2180644 DOI: 10.1002/9780470513880.ch9] [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] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Haemopoietic growth factors stimulate a number of common biochemical and molecular events despite the high specificity of individual ligand-receptor interactions. Analysis of three distinct colony-stimulating factors (CSFs), interleukin 3 (IL-3), granulocyte-CSF and granulocyte macrophage-CSF, and the lymphocytotropic growth factor IL-2 revealed remarkably similar distal subcellular biochemical signals, although the mode of initial membrane signal transduction may differ significantly. Both early progenitor cell growth factors, such as IL-3, and late-acting factors, such as CSF-1, stimulate tyrosine and serine/threonine substrate phosphorylations. One substrate (p68) is phosphorylated in response to many CSFs and to IL-2, suggesting that it plays a highly conserved role in the signal transduction processes of many different receptor(s). The proliferative CSFs and IL-2 also stimulate the expression of many of the same genes, including protooncogenes, the ornithine decarboxylase gene, and members of the phylogenetically ancient family of stress response genes. Thus although initial membrane events may differ among the proliferative stimulants, the biochemical and molecular convergence of signalling pathways on highly conserved cellular substrates and on the programme of gene expression is seen.
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Affiliation(s)
- W L Farrar
- Laboratory of Molecular Immunoregulation, National Cancer Institute, Frederick, Maryland
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52
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Lopashov GV. Regenerative capacity of retinal cells and the maintenance of their differentiation. Ciba Found Symp 2007; 160:209-17; discussion 217-8. [PMID: 1752164 DOI: 10.1002/9780470514122.ch11] [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] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Mechanisms underlying cell type stability and the capacity of retinal cells for transdifferentiation are discussed. It is shown that cells of amphibian pigmented epithelium can be transformed into retina or lens cells depending on the inducing cell type: the influence of retina enables them to be transformed into retina, the influence of lens epithelium, to lens cells (lentoids or lenses). This led to an attempt to discover the molecular character of cell action by means of transfilter induction in early gastrula ectoderm of Xenopus laevis. The results show that the induced cell types correspond to the main inducing cell type, around which a range of neighbouring cell types is produced; this has been shown for five different cell types. The inducing factors involved seem to show qualitative differences. It is probable that they play a stabilizing role in the maintenance of the differentiated state of tissues, since temporary dissociation into cells leads eye tissues to transdifferentiate into other types. Such molecular factors can play a significant role in the maintenance of the type of differentiation and also in conversion into other cell types. These mechanisms of maintenance are not restricted to interactions between molecules and cells, since membranes on the surface of the retina and pigmented epithelium contribute to their shaping and consequently to the stability of the cell type.
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Affiliation(s)
- G V Lopashov
- Institute of Gene Biology, USSR Academy of Sciences, Moscow
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53
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Toole BP, Munaim SI, Welles S, Knudson CB. Hyaluronate-cell interactions and growth factor regulation of hyaluronate synthesis during limb development. Ciba Found Symp 2007; 143:138-45; discussion 145-9 281-5. [PMID: 2680342 DOI: 10.1002/9780470513774.ch9] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Hyaluronate is a major component of the intercellular matrix surrounding proliferating and migrating cells in embryonic tissues. When placed in culture, mesodermal cells from the early, proliferative stages of limb development produce high levels of hyaluronate and exhibit prominent hyaluronate-dependent pericellular coats. Cells from the subsequent stages of mesodermal condensation that precede differentiation to cartilage and muscle produce less hyaluronate and do not exhibit these coats. Also at this time, binding sites specific for hyaluronate appear on the surface of the mesodermal cells. These binding sites may participate in the mechanism of condensation by mediating cell aggregation and the endocytosis of hyaluronate. Further changes in hyaluronate-cell interaction occur during differentiation of the condensed mesoderm to cartilage and muscle. Hyaluronate synthesis and pericellular coat formation in the mesoderm are stimulated by a factor, related to transforming growth factor-beta, that is produced by the surrounding ectoderm. The early limb also contains high levels of basic fibroblast growth factor. Its concentration is highest at the earliest stages, when cell proliferation and hyaluronate synthesis are prominent activities, and this factor has been shown to stimulate both these activities in cultures of limb mesodermal cells. Thus fibroblast growth factor and transforming growth factor-beta may be important in the regulation of early growth and morphogenesis of the limb.
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Affiliation(s)
- B P Toole
- Department of Anatomy and Cellular Biology, Tufts University Health Sciences Center, Boston, MA 02111
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54
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Testa NG, Allen TD, Molineux G, Lord BI, Onions D. Haemopoietic growth factors: their relevance in osteoclast formation and function. Ciba Found Symp 2007; 136:257-74. [PMID: 3068014 DOI: 10.1002/9780470513637.ch16] [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] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The major recent advance in our knowledge of the haemopoietic system has been the purification and characterization of a family of haemopoietic growth factors, and their availability in recombinant form. In the bone marrow the sequences of differentiation and proliferation leading to the production of mature cells that these factors regulate may be determined by the relative availability of the factors in microenvironmental domains. The observation that growth factor-producing cells and haemopoietic progenitor cells are not evenly distributed in the bone marrow leads us to expect that the overall effect of growth factors (and other regulatory molecules) on the production and function of macrophages and osteoclasts may differ when in vivo or in vitro assays are used as end-points and, in the latter case, when whole marrow or purified cell populations are tested. The availability of an in vitro assay in which osteoclast-like cells are generated will allow these concepts to be tested.
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Affiliation(s)
- N G Testa
- Paterson Institute for Cancer Research, Christie Hospital & Holt Radium Institute, Withington, Manchester, UK
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55
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Price DJ, Lotto RB, Warren N, Magowan G, Clausen J. The roles of growth factors and neural activity in the development of the neocortex. Ciba Found Symp 2007; 193:231-50; discussion 251-7. [PMID: 8727495 DOI: 10.1002/9780470514795.ch12] [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] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Previous research on primarily the peripheral nervous system has shown that soluble growth factors help control key developmental events by contributing to dynamic autocrine and paracrine signalling systems. Much less is known about the roles of these substances in neocortical development. Using cell and tissue culture paradigms, we have demonstrated that soluble growth factors are produced by the neocortex and its subcortical targets, and that these tissues can respond to them. There are several possible functions for these factors in neocortical development in vivo: they may initiate axonal growth from neocortical neurons and/or their afferents; accelerate or guide that growth; and/or play a role in the later refinement of connections. Although none of these possibilities can be excluded, the existing evidence strengthens the hypothesis that soluble growth factors are important for the early postnatal growth and refinement of neocortical connections, when their levels of release may be regulated by neocortical activity. At present we do not know which growth factors are involved in these processes, but the results of preliminary experiments indicate that neurotrophins and fibroblast growth factor are prime candidates.
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Affiliation(s)
- D J Price
- Department of Physiology, University of Edinburgh Medical School, UK
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56
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Abstract
Nutrient overload induces constitutive S6K1 (S6 kinase 1) activation, which leads to insulin resistance by suppressing insulin-induced class I PI3K (phosphoinositide 3-kinase) signalling [Um, Frigerio, Watanabe, Picard, Joaquin, Sticker, Fumagalli, Allegrini, Kozma, Auwerx and Thomas (2004) Nature 431, 200-205]. This finding gave rise to the question of the mechanism by which nutrients, such as AAs (amino acids), enter the mTOR (mammalian target of rapamycin)/S6K1 signalling pathway. Counter to the prevailing view, our recent studies have shown that the AA input into the mTOR/S6K1 signalling pathway is not mediated by the tumour suppressor TSC1 (tuberous sclerosis complex 1)/TSC2 or its target, the proto-oncogene Rheb (Ras homologue enriched in brain). Instead, we found that the AA input was mediated by class 3 PI3K, or hVps34 (human vacuolar protein sorting 34). In brief, ectopic expression of hVps34 drives S6K1 activation, but only in the presence of AAs, and this effect is blocked by small interfering RNAs directed against hVps34. Moreover, stimulation of cells with AAs increases hVps34 activity, as indicated by the production of PI3P (phosphatidylinositol 3-phosphate). PI3P mediates the recruitment of proteins containing FYVE (Fab1p, YOTB, Vac1p and EEA1) or PX (Phox homology) domains to endosomal membranes, with PI3P-rich micro-domains acting as signalling platforms. Additional evidence indicating hVps34 as the mediator of AA input to S6K1 came from experiments in which S6K1 activation was attenuated by ectopic expression of a cDNA containing two FYVE domains, which bind to PI3P, preventing binding of proteins containing either FYVE or PX domains [Nobukuni, Joaquin, Roccio, Dann, Kim, Gulati, Byfield, Backer, Natt, Bos, Zwartkruis and Thomas (2005) Proc. Natl. Acad. Sci. U.S.A. 102, 14238-14243].
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Affiliation(s)
- P Gulati
- Genome Research Institute, University of Cincinnati, Cincinnati, OH 45237, USA
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57
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Guthridge MA, Lopez AF. Phosphotyrosine/phosphoserine binary switches: a new paradigm for the regulation of PI3K signalling and growth factor pleiotropy? Biochem Soc Trans 2007; 35:250-2. [PMID: 17371251 DOI: 10.1042/bst0350250] [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] [Indexed: 11/17/2022]
Abstract
Cytokines and growth factors exert multiple biological activities through their ability to engage and activate specific receptors displayed on the surface of cells. How these receptors are able to differentially (and sometimes independently) regulate cell survival, proliferation, differentiation and activation to control quite specific and distinct cellular outcomes is unclear. Similarly, how a single growth factor or cytokine receptor can specify alternate cellular responses and control very different cellular fates is also not known. We present a new mechanism by which cytokines and growth factors are able to control these pleiotropic responses.
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Affiliation(s)
- M A Guthridge
- Cytokine Receptor Laboratory, Department of Human Immunology, Hanson Institute, Institute of Medical and Veterinary Science, Frome Rd, Adelaide, SA, Australia.
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58
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Wilson C, Vereshchagina N, Reynolds B, Meredith D, Boyd CAR, Goberdhan DCI. Extracellular and subcellular regulation of the PI3K/Akt cassette: new mechanisms for controlling insulin and growth factor signalling. Biochem Soc Trans 2007; 35:219-21. [PMID: 17371242 PMCID: PMC2648506 DOI: 10.1042/bst0350219] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [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: 11/17/2022]
Abstract
The PI3K (phosphoinositide 3-kinase)/Akt (also called protein kinase B) signalling cassette plays a central role in the response to growth factors, particularly insulin-like molecules, and its misregulation is a characteristic feature of diabetes and many forms of human cancer. Recent molecular genetic studies initiated in the fruitfly, Drosophila melanogaster, have highlighted two new cell-type-specific mechanisms regulating PI3K/Akt signalling and its downstream effects. First, the cellular response to this cassette is modulated by several classes of cell-surface transporters and sensors, suggesting an important role for extracellular nutrients in insulin-sensitivity. Secondly, various cell types show a markedly different subcellular distribution of the activated kinase Akt, influencing the cellular functions of this molecule. These findings reveal new mechanisms by which processes such as growth, lipogenesis and insulin resistance can be differentially regulated and may suggest novel strategies for treating insulin-linked diseases.
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Affiliation(s)
- C Wilson
- Department of Physiology, Anatomy and Genetics, Le Gros Clark Building, University of Oxford, Oxford, UK.
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59
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Abstract
Regeneration is the ability of cells to restore lost or damaged tissues and organs in adults by pathways that mimic developmental processes. Although many of the molecular mechanisms that control cellular differentiation and growth during embryogenesis recur during fracture healing, these processes take place in a postnatal environment that is unique and distinct from those that exist during embryogenesis. Bone tissue has a remarkable capacity of regeneration without scarring. This article highlights central biological and molecular processes that are crucial in embryonic bone development. Several animal bone regeneration models are described. The patterns of gene expression during the regeneration process in the different models are reviewed. Exploring the similarities and the differences in the molecular processes in different models will contribute to the understanding of their potential in the processes of bone regeneration and tissue engineering.
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Affiliation(s)
- H Bahar
- Department of Oral Biology, Maurice and Gabriela Goldschleger School of Dental Medicine, Tel Aviv University, Tel Aviv 69978, Israel
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60
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Abstract
Lymphatic vasculature has recently emerged as a prominent area in biomedical research because of its essential role in the maintenance of normal fluid homeostasis and the involvement in pathogenesis of several human diseases, such as solid tumor metastasis, inflammation and lymphedema. Identification of lymphatic endothelial specific markers and regulators, such as VEGFR-3, VEGF-C/D, PROX1, podoplanin, LYVE-1, ephrinB2 and FOXC2, and the development of mouse models have laid a foundation for our understanding of the major steps controlling growth and remodeling of lymphatic vessels. In this review we summarize recent advances in the field and discuss how this knowledge as well as use of model organisms, such as zebrafish and Xenopus, should allow further in depth analysis of the lymphatic vascular system.
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Affiliation(s)
- T Mäkinen
- Cancer Research UK London Research Institute, 44 Lincoln's Inn Fields, London, WC2A 3PX, UK
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61
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von Haussen J, Koczulla R, Shaykhiev R, Herr C, Pinkenburg O, Reimer D, Wiewrodt R, Biesterfeld S, Aigner A, Czubayko F, Bals R. The host defence peptide LL-37/hCAP-18 is a growth factor for lung cancer cells. Lung Cancer 2007; 59:12-23. [PMID: 17764778 DOI: 10.1016/j.lungcan.2007.07.014] [Citation(s) in RCA: 112] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2007] [Revised: 07/06/2007] [Accepted: 07/15/2007] [Indexed: 12/18/2022]
Abstract
Cancer development can be viewed as dysregulated repair. Antimicrobial peptides (AMPs) are effector molecules of the innate immune system with direct antimicrobial activity. Beside this host defence function several AMPs play a role in the regulation of inflammation and tissue repair. The aim of the present study was to investigate whether the human cathelicidin AMP LL-37/hCAP-18 is involved in the biology of lung cancer. Human cancer cell lines were found to express the human cathelicidin LL-37/hCAP-18 mRNA and peptide at different levels. Immunohistochemistry of human lung cancers showed that the peptide is expressed mostly in adenocarcinoma and squamous cell carcinoma. Application of exogenous LL-37 at low concentrations of 5ng/ml to cancer cell lines increased proliferation and growth of anchorage-independent colonies. At the molecular level, LL-37 induced phosphorylation of the epidermal growth factor receptor (EGFR) and activation of downstream MAP kinase signalling pathways. Lung cancer cell lines that stably overexpress the peptide by means of a doxycycline-regulated promoter system also showed a faster growth. When these cell lines were injected subcutaneously into nude mice, cathelicidin overexpression resulted in increased tumourigenicity and the formation of significantly larger tumours. In conclusion, cathelicidin is expressed in human lung cancers. The peptide activates tumour cells resulting in increased cell growth in vitro and in an animal model. The host defence peptide cathelicidin LL-37/hCAP-18 acts as growth factor for human lung cancer.
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Affiliation(s)
- Judith von Haussen
- Department of Internal Medicine, Philipps-University, 35043 Marburg, Germany
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62
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Watanabe K, Bianco C, Strizzi L, Hamada S, Mancino M, Bailly V, Mo W, Wen D, Miatkowski K, Gonzales M, Sanicola M, Seno M, Salomon DS. Growth factor induction of Cripto-1 shedding by glycosylphosphatidylinositol-phospholipase D and enhancement of endothelial cell migration. J Biol Chem 2007; 282:31643-55. [PMID: 17720976 DOI: 10.1074/jbc.m702713200] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [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: 11/06/2022] Open
Abstract
Cripto-1 (CR-1) is a glycosylphosphatidylinositol (GPI)-anchored membrane glycoprotein that has been shown to play an important role in embryogenesis and cellular transformation. CR-1 is reported to function as a membrane-bound co-receptor and as a soluble ligand. Although a number of studies implicate the role of CR-1 as a soluble ligand in tumor progression, it is unclear how transition from the membrane-bound to the soluble form is physiologically regulated and whether differences in biological activity exist between these forms. Here, we demonstrate that CR-1 protein is secreted from tumor cells into the conditioned medium after treatment with serum, epidermal growth factor, or lysophosphatidic acid, and this soluble form of CR-1 exhibits the ability to promote endothelial cell migration as a paracrine chemoattractant. On the other hand, membrane-bound CR-1 can stimulate endothelial cell sprouting through direct cell-cell interaction. Shedding of CR-1 occurs at the GPI-anchorage site by the activity of GPI-phospholipase D (GPI-PLD), because CR-1 shedding was suppressed by siRNA knockdown of GPI-PLD and enhanced by overexpression of GPI-PLD. These findings describe a novel molecular mechanism of CR-1 shedding, which may contribute to endothelial cell migration and possibly tumor angiogenesis.
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Affiliation(s)
- Kazuhide Watanabe
- Tumor Growth Factor Section, Mammary Biology & Tumorigenesis Laboratory, Center for Cancer Research, NCI, National Institutes of Health, Bethesda, Maryland 20892, USA
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63
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Gardiner SM, Keyte J, Bennett T. Reply to 'Salusins: newly identified bioactive peptides with hemodynamic and mitogenic activities'. Nat Med 2007; 13:661; author reply 661-2. [PMID: 17554326 DOI: 10.1038/nm0607-661a] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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64
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Siriwardhana N, Choudhary S, Wang HCR. Precancerous model of human breast epithelial cells induced by NNK for prevention. Breast Cancer Res Treat 2007; 109:427-41. [PMID: 17653854 DOI: 10.1007/s10549-007-9666-9] [Citation(s) in RCA: 22] [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: 10/25/2006] [Accepted: 06/26/2007] [Indexed: 12/01/2022]
Abstract
Epidemiological investigations have suggested that exposure to tobacco and environmental carcinogens increase the risk of developing human breast cancer. In light of the chronic exposure of human breast tissues to tobacco and environmental carcinogens, we have taken an approach of analyzing cellular changes of immortalized non-cancerous human breast epithelial MCF10A cells during the acquisition of cancerous properties induced by repeated exposure to the tobacco-specific carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) at a low concentration of 100 pM. We found that accumulated exposures of MCF10A cells to NNK result in progressive development of cellular carcinogenesis from a stage of immortalization to precancerous sub-stages of acquiring a reduced dependence on growth factors and acquiring anchorage-independent growth. Using Matrigel for MCF10A cells to form size-restricted acini, we detected that exposures to NNK resulted in altered acinar conformation. Analysis of gene expression profiles by cDNA microarrays revealed up- and down-regulated genes associated with NNK-induced carcinogenesis. Using this cellular carcinogenesis model as a target system to identify anticancer agents, we detected that grape seed proanthocyanadin extract significantly suppressed NNK-induced carcinogenesis of MCF10A cells. Our studies provide a carcinogenesis-cellular model mimicking the accumulative exposure to carcinogens in the progression of human breast epithelial cells to increasingly acquire cancerous properties, as likely occurs in the development of precancerous human breast cells. Our cellular model also serves as a cost-efficient, in vitro system to identify preventive agents that inhibit human breast cell carcinogenesis induced by chronic exposures to carcinogens.
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Affiliation(s)
- Nalin Siriwardhana
- Anticancer Molecular Oncology Laboratory, Department of Pathobiology, College of Veterinary Medicine, University of Tennessee, 2407 River Drive, Knoxville, TN, 37996, USA
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65
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Zhu CQ, Popova SN, Brown ERS, Barsyte-Lovejoy D, Navab R, Shih W, Li M, Lu M, Jurisica I, Penn LZ, Gullberg D, Tsao MS. Integrin alpha 11 regulates IGF2 expression in fibroblasts to enhance tumorigenicity of human non-small-cell lung cancer cells. Proc Natl Acad Sci U S A 2007; 104:11754-9. [PMID: 17600088 PMCID: PMC1913903 DOI: 10.1073/pnas.0703040104] [Citation(s) in RCA: 120] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Integrin alpha11 (ITGA11/alpha11) is localized to stromal fibroblasts and commonly overexpressed in non-small-cell lung carcinoma (NSCLC). We hypothesized that stromal alpha11 could be important for the tumorigenicity of NSCLC cells. SV40 immortalized mouse embryonic fibroblasts established from wild-type (WT) and Itga11-deficient [knockout (KO)] mice were tested for their tumorigenicity in immune-deficient mice when implanted alone or coimplanted with the A549 human lung adenocarcinoma cells. A549 coimplanted with the fibroblasts showed a markedly enhanced tumor growth rate compared with A549, WT, or KO, which alone formed only small tumors. Importantly, the growth was significantly greater for A549+WT compared with A549+KO tumors. Reexpression of human alpha11 cDNA in KO cells rescued a tumor growth rate to that comparable with the A549+WT tumors. These findings were validated in two other NSCLC cell lines, NCI-H460 and NCI-H520. Gene expression profiling indicated that IGF2 mRNA expression level was >200 times lower in A549+KO compared with A549+WT tumors. Stable short-hairpin RNA (shRNA) down-regulation of IGF2 in WT (WT(shIGF2)) fibroblasts resulted in a decreased growth rate of A549+WT(shIGF2), compared with A549+WT tumors. The results indicate that alpha11 is an important stromal factor in NSCLC and propose a paradigm for carcinoma-stromal interaction indirectly through interaction between the matrix collagen and stromal fibroblasts to stimulate cancer cell growth.
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MESH Headings
- Adenocarcinoma/genetics
- Adenocarcinoma/metabolism
- Adenocarcinoma/pathology
- Animals
- Carcinoma, Non-Small-Cell Lung/genetics
- Carcinoma, Non-Small-Cell Lung/metabolism
- Carcinoma, Non-Small-Cell Lung/pathology
- Carcinoma, Squamous Cell/genetics
- Carcinoma, Squamous Cell/metabolism
- Carcinoma, Squamous Cell/pathology
- Cell Line, Transformed
- Cell Line, Tumor
- Collagen/metabolism
- Extracellular Matrix/genetics
- Extracellular Matrix/metabolism
- Extracellular Matrix/pathology
- Fibroblasts/metabolism
- Gene Expression Regulation, Neoplastic/physiology
- Growth Substances/biosynthesis
- Growth Substances/genetics
- Growth Substances/physiology
- Humans
- Insulin-Like Growth Factor II
- Integrin alpha Chains/deficiency
- Integrin alpha Chains/genetics
- Integrin alpha Chains/physiology
- Lung Neoplasms/genetics
- Lung Neoplasms/metabolism
- Lung Neoplasms/pathology
- Male
- Mice
- Mice, Knockout
- Mice, SCID
- Proteins/genetics
- Proteins/metabolism
- Stromal Cells/metabolism
- Stromal Cells/pathology
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Affiliation(s)
- Chang-Qi Zhu
- *Ontario Cancer Institute and Princess Margaret Hospital, University Health Network, Toronto, ON, Canada M5G 2M9
| | - Svetlana N. Popova
- Department of Biomedicine, Division of Physiology, University of Bergen, Jonas Lies vei 91, 5009 Bergen, Norway; and
| | - Ewan R. S. Brown
- *Ontario Cancer Institute and Princess Margaret Hospital, University Health Network, Toronto, ON, Canada M5G 2M9
| | - Dalia Barsyte-Lovejoy
- *Ontario Cancer Institute and Princess Margaret Hospital, University Health Network, Toronto, ON, Canada M5G 2M9
| | - Roya Navab
- *Ontario Cancer Institute and Princess Margaret Hospital, University Health Network, Toronto, ON, Canada M5G 2M9
| | - Warren Shih
- *Ontario Cancer Institute and Princess Margaret Hospital, University Health Network, Toronto, ON, Canada M5G 2M9
| | - Ming Li
- *Ontario Cancer Institute and Princess Margaret Hospital, University Health Network, Toronto, ON, Canada M5G 2M9
| | - Ming Lu
- *Ontario Cancer Institute and Princess Margaret Hospital, University Health Network, Toronto, ON, Canada M5G 2M9
| | - Igor Jurisica
- *Ontario Cancer Institute and Princess Margaret Hospital, University Health Network, Toronto, ON, Canada M5G 2M9
- Departments of Medical Biophysics
- Computer Science, and
| | - Linda Z. Penn
- *Ontario Cancer Institute and Princess Margaret Hospital, University Health Network, Toronto, ON, Canada M5G 2M9
- Departments of Medical Biophysics
| | - Donald Gullberg
- Department of Biomedicine, Division of Physiology, University of Bergen, Jonas Lies vei 91, 5009 Bergen, Norway; and
| | - Ming-Sound Tsao
- *Ontario Cancer Institute and Princess Margaret Hospital, University Health Network, Toronto, ON, Canada M5G 2M9
- Departments of Medical Biophysics
- Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada M5G 2M9
- **To whom correspondence should be addressed.
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66
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Abstract
Genesis of plaque lesion as atherosclerosis is based on the involvement of endothelium and smooth muscle cells
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Affiliation(s)
- Lawrence M Agius
- Department of Pathology, St Luke's Hospital, Tal-Virtu, Rabat RBT09, Malta.
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67
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Burns KA, Vanden Heuvel JP. Modulation of PPAR activity via phosphorylation. Biochim Biophys Acta Mol Cell Biol Lipids 2007; 1771:952-60. [PMID: 17560826 PMCID: PMC2712836 DOI: 10.1016/j.bbalip.2007.04.018] [Citation(s) in RCA: 322] [Impact Index Per Article: 18.9] [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] [Received: 10/28/2006] [Revised: 03/06/2007] [Accepted: 04/30/2007] [Indexed: 02/08/2023]
Abstract
Peroxisome proliferator-activated receptors (PPARs) are members of the nuclear receptor superfamily of transcription factors that respond to specific ligands by altering gene expression in a cell-, developmental- and sex-specific manner. Three subtypes of this receptor have been discovered (PPARalpha, beta and gamma), each apparently evolving to fulfill different biological niches. PPARs control a variety of target genes involved in lipid homeostasis, diabetes and cancer. Similar to other nuclear receptors, the PPARs are phosphoproteins and their transcriptional activity is affected by cross-talk with kinases and phosphatases. Phosphorylation by the mitogen-activated protein kinases (ERK- and p38-MAPK), Protein Kinase A and C (PKA, PKC), AMP Kinase (AMPK) and glycogen synthase kinase-3 (GSK3) affect their activity in a ligand-dependent or -independent manner. The effects of phosphorylation depend on the cellular context, receptor subtype and residue metabolized which can be manifested at several steps in the PPAR activation sequence including ligand affinity, DNA binding, coactivator recruitment and proteasomal degradation. The review will summarize the known PPAR kinases that directly act on these receptors, the sites affected and the result of this modification on receptor activity.
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Affiliation(s)
| | - John P. Vanden Heuvel
- To whom correspondence should be addressed: Jack Vanden Heuvel, PhD, Professor of Molecular Toxicology, Penn State University, 325 Life Sciences Building, University Park, PA 16802, T: (814) 863-8532, F: (814) 863-1696, , jackvh.cas.psu.edu
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Lee SO, Chun JY, Nadiminty N, Lou W, Gao AC. Interleukin-6 undergoes transition from growth inhibitor associated with neuroendocrine differentiation to stimulator accompanied by androgen receptor activation during LNCaP prostate cancer cell progression. Prostate 2007; 67:764-73. [PMID: 17373716 DOI: 10.1002/pros.20553] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
BACKGROUND Interleukin-6 (IL-6) has been implicated in the modulation of growth and differentiation in many cancers, and is associated with poor prognosis in renal cell carcinoma, ovarian cancer, lymphoma, melanoma, and prostate cancer. The effects of IL-6 on the growth of LNCaP human prostate cancer cells are puzzling with some groups showing growth stimulation, while others showing growth inhibition. In this study, we investigated the discrepancy of the effects of IL-6 on prostate cancer cells. METHODS Series of lower and higher passages of LNCaP cell sublines were generated by a long-term exposure of LNCaP cells in IL-6-containing culture media. The characteristics of these cell sublines were analyzed and the potential roles of neuroendocrine (NE) differentiation and androgen receptor (AR) activation were examined. RESULTS We demonstrated that while short-term treatment of IL-6 inhibits LNCaP cell growth by a paracrine mechanism associated with NE differentiation, long-term treatment of IL-6 promotes LNCaP cell growth by an autocrine mechanism accompanied by an activation of AR signaling. In the lower passages (less than 28 passages) of LNCaP cells treated with IL-6, the cell growth was severely retarded which is associated with NE-like morphology and increased expression of NE markers such as neuronspecific enolase (NSE) and chromgranin A (ChgA), and loss of AR expression. However, in the higher passages (higher than 42 passages) of LNCaP cells treated with IL-6, cells started to express endogenous IL-6. At the same time, NE characteristics were disappeared, AR signaling was activated and cells growth was accelerated. Knocking down the AR activation of the higher passages of LNCaP cells abolished autocrine IL-6-induced growth stimulation. CONCLUSIONS These studies suggest that acquisition of endogenous IL-6 production after prolong exposure of prostate cancer cells to IL-6 may contribute to an autocrine cell growth stimulation. Furthermore, the transition of IL-6 from a paracrine growth inhibitor to an autocrine growth stimulator suggests that IL-6 plays an important role during prostate cancer progression, possibly androgen-independent progression.
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Affiliation(s)
- Soo Ok Lee
- Departments of Medicine, Roswell Park Cancer Institute, Buffalo, New York 14263, USA
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69
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70
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Zheng H, Stratton CJ, Morozumi K, Jin J, Yanagimachi R, Yan W. Lack of Spem1 causes aberrant cytoplasm removal, sperm deformation, and male infertility. Proc Natl Acad Sci U S A 2007; 104:6852-7. [PMID: 17426145 PMCID: PMC1871874 DOI: 10.1073/pnas.0701669104] [Citation(s) in RCA: 110] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
We identified a previously uncharacterized gene, spermatid maturation 1 (Spem1), encoding a protein exclusively expressed in the cytoplasm of steps 14-16 elongated spermatids in the mouse testis. This protein contains no known functional domains and is highly conserved across mammalian species. Male mice deficient in Spem1 were completely infertile because of deformed sperm characterized by a bent head wrapped around by the neck and the middle piece of the tail. We show that lack of Spem1 causes failure of the cytoplasm to become loose and detach from the head and the neck region of the developing spermatozoa. Retained cytoplasmic components mechanically obstruct the straightening of the sperm head and the stretching of the growing tail, leading to the bending of the head in the neck, followed by the wrapping of the head by the neck or the middle piece of the sperm tail. Our study reveals that proper cytoplasm removal is a genetically regulated process requiring the participation of Spem1 and that lack of Spem1 causes sperm deformation and male infertility.
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Affiliation(s)
- Huili Zheng
- *Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, NV 89557; and
| | - Clifford J. Stratton
- *Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, NV 89557; and
| | - Kazuto Morozumi
- Institute for Biogenesis Research, John. A. Burns School of Medicine, University of Hawaii, Honolulu, HI 96822
| | - Jingling Jin
- *Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, NV 89557; and
| | - Ryuzo Yanagimachi
- Institute for Biogenesis Research, John. A. Burns School of Medicine, University of Hawaii, Honolulu, HI 96822
- To whom correspondence may be addressed at:
Department of Physiology and Cell Biology, University of Nevada School of Medicine, Anderson Biomedical Science Building 105C/111, 1664 North Virginia Street, MS 352, Reno, NV 89557. E-mail: or
| | - Wei Yan
- *Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, NV 89557; and
- To whom correspondence may be addressed at:
Department of Physiology and Cell Biology, University of Nevada School of Medicine, Anderson Biomedical Science Building 105C/111, 1664 North Virginia Street, MS 352, Reno, NV 89557. E-mail: or
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71
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Yuan N, Ran X. [Application of autologous platelet-rich gel to refractory chronic diabetic cutaneous ulcers]. Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi 2007; 21:426-9. [PMID: 17546893] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
OBJECTIVE To review and evaluate the clinical application of autologous platelet-rich gel (APG) in refractory chronic diabetic cutaneous ulcers. METHODS The latest literature was extensively reviewed, and the potential mechanism of APG for healing diabetic cutaneous ulcers was discussed. RESULTS APG accelerated the ulcer healing, especially in healing the refractory diabetic cutaneous ulcers, and the high-level growth factors from the platelet releasate were thought to be the major potential mechanism of the APG action. CONCLUSION APG can promote the healing of refractory chronic diabetic cutaneous ulcers. Topical haemotherapy with APG may be considered an adjuvant treatment of a multidisciplinary process and may be useful to the effective therapy of cutaneous ulcers.
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Affiliation(s)
- Nanbing Yuan
- Diabetic Foot Care Center, Department of Endocrinology, West China Hospital, Sichuan University, Chengdu Sichuan, 610041, P. R. China
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72
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Hann CL, Rudin CM. Fast, hungry and unstable: finding the Achilles' heel of small-cell lung cancer. Trends Mol Med 2007; 13:150-7. [PMID: 17324626 PMCID: PMC4124625 DOI: 10.1016/j.molmed.2007.02.003] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [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] [Received: 09/28/2006] [Revised: 01/23/2007] [Accepted: 02/14/2007] [Indexed: 12/14/2022]
Abstract
Over 95% of patients with small-cell lung cancer (SCLC) die within five years of diagnosis. The standard of care and the dismal prognosis for this disease have not changed significantly over the past 25 years. Some of the characteristics of SCLC that have defined it as a particularly virulent form of cancer -- rapid proliferation, excessive metabolic and angiogenic dependence, apoptotic imbalance and genetic instability -- are now being pursued as tumor-specific targets for intervention both in preclinical and early phase clinical studies. Here, we summarize areas of ongoing anti-cancer drug development, including classes of agents that target essential pathways regulating proliferation, angiogenesis, apoptotic resistance, chromosomal and protein stability, and cell-cell and cell-matrix interaction.
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Affiliation(s)
- Christine L Hann
- Department of Oncology, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University Cancer Research, Building 2, Baltimore, MD 21231, USA
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73
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Mimeault M, Batra SK. Interplay of distinct growth factors during epithelial mesenchymal transition of cancer progenitor cells and molecular targeting as novel cancer therapies. Ann Oncol 2007; 18:1605-19. [PMID: 17355951 DOI: 10.1093/annonc/mdm070] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.3] [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] [Indexed: 12/17/2022] Open
Abstract
In this review, we describe the critical functions assumed by the interplay of epidermal growth factor, hedgehog, Wnt/beta-catenin, tumor growth factor-beta and integrin signaling cascades in tumorigenic and migrating cancer progenitor cells and activated stromal cells during carcinogenesis. These growth factors provide an important role for the sustained growth and survival of tumorigenic cancer progenitor cells and their progeny by up-regulating numerous mitotic and antiapoptotic signaling cascades. Furthermore, these potent morphogens may cooperate for inducing the molecular events associated with the epithelial-mesenchymal program in cancer cells including the alterations in epithelial cell shape and motility through the dissociation of intercellular adherens junctions. Of therapeutic interest, new strategies for the development of more effective clinical treatments against the locally aggressive and invasive cancers based on the molecular targeting of deregulated signaling elements in tumorigenic and migrating cancer cells and their local microenvironment are also described.
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Affiliation(s)
- M Mimeault
- Department of Biochemistry and Molecular Biology, Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, NE 68198-5870, USA.
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74
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Abstract
Ribosome assembly occurs co-transcriptionally on the rRNA genes. This process requires the co-ordinated expression and assembly of many hundreds of proteins and is finely tuned to cell and organism growth. Co-ordinate regulation of the rRNA genes and the ribosomal protein genes is therefore essential for high-fidelity ribosome assembly. Recent work shows that rRNA gene transcription is regulated at the level of elongation via the mitogen-activated protein kinase pathway. We argue that this may provide an explanation for the high fidelity of ribosome assembly.
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Affiliation(s)
- T Moss
- Cancer Research Centre and Department of Medical Biology, Laval University, CHUQ-HDQ, Pavillon St. Patrick, 9 rue McMahon, QC, Canada G1R 3S3.
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75
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Abstract
Recent development of biomedical engineering including biomaterials and drug delivery system (DDS) as well as basic biology and medicine has enabled cells to induce regeneration repairing of defective tissues as well as substitute the biological functions of damaged organs. For successful tissue regeneration, it is undoubtedly indispensable to give cells a local environment which allows cells to efficiently promote their proliferation and differentiation and consequently induce cell-based tissue regeneration. Tissue engineering is one of the biomedical forms to create this regeneration environment of cells. The tissue and organ repairing based on their regeneration induction has been realized by combining cells with the tissue engineering technology or methodology in a surgical or internally medical manner. This paper overviews the present status and future direction of tissue engineering for regenerative inductive therapy, briefly explaining the key technology of tissue engineering, especially DDS of growth factor and gene.
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Affiliation(s)
- Yasuhiko Tabata
- Department of Biomaterials, Field of Tissue Engineering, Institute for Frontier Medical Sciences, Kyoto University, Sakyo-ku, Kyoto, 606-8507, Japan.
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Abstract
Recurrent glioblastoma multiforme is a lethal disease with currently available treatment options having a limited impact on outcome. In this article, current and novel therapeutic approaches in the treatment of recurrent glioblastoma multiforme, including chemotherapy, targeted molecular agents, virotherapy/gene therapy and immunotherapy and challenges in developing novel therapeutic agents for glioblastoma multiforme will be discussed.
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Affiliation(s)
- Lijo Simpson
- Mayo Clinic, Department of Oncology, 200 1st Str SW, Rochester, MN 55905, USA.
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Sicard F, Ehrhart-Bornstein M, Corbeil D, Sperber S, Krug AW, Ziegler CG, Rettori V, McCann SM, Bornstein SR. Age-dependent regulation of chromaffin cell proliferation by growth factors, dehydroepiandrosterone (DHEA), and DHEA sulfate. Proc Natl Acad Sci U S A 2007; 104:2007-12. [PMID: 17264205 PMCID: PMC1794270 DOI: 10.1073/pnas.0610898104] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
The adrenal gland comprises two endocrine tissues of distinct origin, the catecholamine-producing medulla and the steroid-producing cortex. The inner adrenocortical zone, which is in direct contact with the adrenomedullary chromaffin cells, produces dehydroepiandrostendione (DHEA) and DHEA sulfate (DHEAS). These two androgens exhibit potential effects on neurogenesis, neuronal survival, and neuronal stem cell proliferation. Unlike the closely related sympathetic neurons, chromaffin cells are able to proliferate throughout life. The aim of this study was to investigate the effect of DHEA and DHEAS on proliferation of bovine chromaffin cells from young and adult animals. We demonstrated that graded concentrations of leukemia inhibitory factor induced proliferation of chromaffin cells from young animals, whereas EGF had no effect. On the contrary, EGF increased the cell proliferation in cells from adult animals, whereas leukemia inhibitory factor was inactive. In both cases, DHEA decreased the proliferative effect induced by the growth factors. Surprisingly, DHEAS enhanced, in a dose-dependent-manner, the effect of growth factors on proliferation in cells from adult animals but not from young animals. Flutamide, ICI 182,780, and RU 486 had no effect on the action of DHEA or DHEAS on chromaffin cell proliferation. These data show that DHEA and its sulfated form, DHEAS, differentially regulate growth-factor-induced proliferation of bovine chromaffin cells. In addition, the sensitivity of chromaffin cells to different growth factors is age-dependent. Furthermore, these two androgens may act through a receptor other than the classical steroid receptors.
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Affiliation(s)
- Flavie Sicard
- *Department of Medicine, Carl Gustav Carus University Medical School, and
- To whom correspondence may be addressed at:
Carl Gustav Carus University Hospital, University of Dresden, Fetscherstrasse 74, 01307 Dresden, Germany. E-mail:
| | | | - Denis Corbeil
- Tissue Engineering Laboratories, Biotechnology Center, University of Technology, 01307 Dresden, Germany; and
| | - Simone Sperber
- *Department of Medicine, Carl Gustav Carus University Medical School, and
| | - Alexander W. Krug
- *Department of Medicine, Carl Gustav Carus University Medical School, and
| | | | - Valeria Rettori
- Centro de Estudios Farmocógicos y Botánicos, Consejo Nacional de Investigaciones Científicas y Técnicas, Serrano 669, 1414 Buenos Aires, Argentina
| | - Samuel M. McCann
- Centro de Estudios Farmocógicos y Botánicos, Consejo Nacional de Investigaciones Científicas y Técnicas, Serrano 669, 1414 Buenos Aires, Argentina
- To whom correspondence may be addressed. E-mail:
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78
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Abstract
Bioactive (neuro)peptides play critical roles in regulating most biological processes in animals. Peptides belonging to the same family are characterized by a typical sequence pattern that is conserved among the family's peptide members. Such a conserved pattern or motif usually corresponds to the functionally important part of the biologically active peptide. In this paper, all known bioactive (neuro)peptides annotated in Swiss-Prot and TrEMBL protein databases are collected, and the pattern searching program Pratt is used to search these unaligned peptide sequences for conserved patterns. The obtained patterns are then refined by combining the information on amino acids at important functional sites collected from the literature. All the identified patterns are further tested by scanning them against Swiss-Prot and TrEMBL protein databases. The diagnostic power of each pattern is validated by the fact that any annotated protein from Swiss-Prot and TrEMBL that contains one of the established patterns, is indeed a known (neuro)peptide precursor. We discovered 155 novel peptide patterns in addition to the 56 established ones in the PROSITE database. All the patterns cover 110 peptide families. Fifty-five of these families are not characterized by the PROSITE signatures, and 12 are also not identified by other existing motif databases, such as Pfam and SMART. Using the newly identified peptide signatures as a search tool, we predicted 95 hypothetical proteins as putative peptide precursors.
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Affiliation(s)
- Feng Liu
- Data Analysis & Modeling Group, Transportation Research Institute, Hasselt University, Building D, 3590 Diepenbeek, Belgium
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79
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Luo Y, Kobler JB, Zeitels SM, Langer R. Effects of Growth Factors on Extracellular Matrix Production by Vocal Fold Fibroblasts in 3-Dimensional Culture. ACTA ACUST UNITED AC 2006; 12:3365-74. [PMID: 17518673 DOI: 10.1089/ten.2006.12.3365] [Citation(s) in RCA: 47] [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: 11/12/2022]
Abstract
Culturing cells in 3-dimensional (3D) systems is important in tissue engineering and in fundamental studies of cellular mechanisms that are sensitive or specific to the 3D environment. To guide the engineering of artificial vocal fold lamina propria tissue, we developed 3D cultures containing human vocal fold fibroblasts (hVFFs) dispersed in a synthetic peptide hydrogel matrix. Growth factors were added to the culture to examine their influence on extracellular matrix (ECM) synthesis, cell proliferation, and matrix contraction. The hVFF-hydrogel constructs were treated with transforming growth factor-beta 1 (TGF-beta1), basic fibroblast growth factor (bFGF), or hepatocyte growth factor (HGF), and the culture was maintained for 21 days. TGF-beta1 induced matrix contraction and enhanced collagen and sulfated glycosaminoglycan production, bFGF effectively increased cell proliferation, and HGF stimulated synthesis of hyaluronic acid and elastin with less collagen accumulation than other conditions. Of the growth factors tested, HGF appears to be most useful for stimulating essential tissue components for restoring vocal fold pliability. The results also suggest that multiple growth factors might be employed sequentially or in combination to program the makeup of cell-hydrogel constructs for vocal fold tissue repair.
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Affiliation(s)
- Ying Luo
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
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80
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McLaughlin N, Annabi B, Sik Kim K, Bahary JP, Moumdjian R, Béliveau R. The response to brain tumor-derived growth factors is altered in radioresistant human brain endothelial cells. Cancer Biol Ther 2006; 5:1539-45. [PMID: 17102591 DOI: 10.4161/cbt.5.11.3459] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
INTRODUCTION Radioresistant brain tumor vasculature is thought to hamper the efficiency of adjuvant cancer therapies. However, little is known regarding the signalling pathways involved in the angiogenic response to brain tumor-derived growth factors in irradiated human brain microvascular endothelial cells (HBMEC). The goal of this study is to assess the effect of ionizing radiation (IR) on HBMEC survival, migration and tubulogenesis. METHODS HBMEC were cultured and irradiated at sublethal single doses. Cell survival was assessed by nuclear cell counting and flow cytometry. HBMEC migration in response to brain tumor-derived growth factors (U-87 GF) and tubulogenesis were assayed using modified Boyden chambers and Matrigel, respectively. RESULTS We observed that single administration of 3-10 Gy IR doses only reduced cell survival by 30%. Radioresistant HBMEC overexpressed RhoA, a small GTPase protein regulating cellular adhesion and migration, and Rho-kinase (ROK), a serine-threonine protein kinase and one of RhoA's major targets. HBMEC migration was induced by vascular endothelial growth factor (VEGF), but even more so in response to sphingo-sine-1-phosphate (S1P) and to U-87 GF. Following IR exposure, HBMEC basal migration increased more than two-fold, whereas the response to S1P and to U-87 GF was significantly diminished. Similarly, the inhibitor of ROK Y-27632 decreased HBMEC migration in response to S1P and U-87 GF. Overexpression of RhoA decreased tubulogenesis, an effect also observed in irradiated HBMEC. CONCLUSION Our results suggest that radioresistant HBMEC migration response to tumor-secreted growth factors and tubulogenesis are altered following IR. The RhoA/ROK signalling pathway is involved in the IR-altered angiogenic functions and may represent a potential molecular target for enhancing the impact of radiotherapy on tumor-associated endothelial cells.
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Affiliation(s)
- Nancy McLaughlin
- Laboratoire de Médecine Moléculaire, Centre de Cancérologie Charles-Bruneau, Hôpital Sainte-Justine-UQAM, Montreal, Quebec, Canada
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81
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Hamilton GA. Peroxisomal oxidases and suggestions for the mechanism of action of insulin and other hormones. Adv Enzymol Relat Areas Mol Biol 2006; 57:85-178. [PMID: 2863924 DOI: 10.1002/9780470123034.ch2] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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82
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Abstract
Muscle damage with a lack of regeneration, manifests itself in several life-threatening diseases, including cancer cachexia, congestive heart failure, AIDS and sepsis. Often misdiagnosed as a condition simply of weight loss, cachexia is actually a highly complex metabolic disorder involving features of anorexia, anaemia, lipolysis and insulin resistance. A significant loss of lean body mass arises from such conditions, resulting in wasting of skeletal muscle. Unlike starvation, the weight loss seen in chronic illnesses arises equally from loss of muscle and of fat. The cachectic state is particularly problematic in cancer, typifying poor prognosis and often lowering responses to chemotherapy and radiation treatment. More than half of cancer patients suffer from cachexia, and strikingly, nearly one-third of cancer deaths are related to cachexia rather than the tumour burden. In considering this disorder, we are faced with a conundrum; how is it possible for uncontrolled growth to prevail in the tumour, in the face of unrestrained tissue loss in our muscles? Consistently, the catabolic state has been associated with a shift in the homeostatic balance between muscle synthesis and degradation mediated by the actions of growth factors and cytokines. Indeed, tumour necrosis factor-alpha (TNF-alpha) levels are raised in several animal models of cachectic muscle wasting, whereas the insulin-like growth factor (IGF) system acts potently to regulate muscle development, hypertrophy and maintenance. This concept of skeletal muscle homeostasis, often viewed as the net balance between two separate processes of protein synthesis and degradation has however changed. More recently, the view is that these two biochemical processes are not occurring independently of each other but in fact are finely co-ordinated by a web of intricate signalling networks. This review, therefore, aims to discuss data currently available regarding the mechanisms of degeneration and regeneration with specific emphasis on the potential and controversial cross-talk which may exist between anabolic growth factors (e.g. IGF-I) and catabolic cytokines (e.g. TNF-alpha). Also importantly, the potential impact at a cellular level of exercise, diet and age will be addressed. Finally, the ability to 'hi-jack' signalling pathways traditionally believed to be for growth and survival or death will be reviewed. It is anticipated that such a review will highlight significant gaps in our knowledge of the cachectic state as well as provide caution with regards to therapeutics suggesting total block on inflammatory processes such as that associated with TNF-alpha action.
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Affiliation(s)
- Amarjit Saini
- Institute for Biophysical and Clinical Research into Human Movement, Department of Exercise and Sport Science, Manchester Metropolitan University, Hassall Road, Alsager, Cheshire ST7 2HL, England, UK.
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Tanaka Y, Yamaguchi S, Fujii-Taira I, Iijima R, Natori S, Homma KJ. Involvement of insect-derived growth factor (IDGF) in the cell growth of an embryonic cell line of flesh fly. Biochem Biophys Res Commun 2006; 350:334-8. [PMID: 17011515 DOI: 10.1016/j.bbrc.2006.09.047] [Citation(s) in RCA: 3] [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] [Received: 09/01/2006] [Accepted: 09/09/2006] [Indexed: 01/16/2023]
Abstract
Insect-derived growth factor (IDGF) is the first adenosine deaminase-related growth factor (ADGF) purified from the conditioned medium of NIH-Sape-4, an embryonic cell line of Sarcophaga peregrina (flesh fly). Here we show the requirement of IDGF for the growth of NIH-Sape-4 cells. Growth factor activity was abolished by adsorption of IDGF from the conditioned medium of NIH-Sape-4 cells. In addition, knockdown of IDGF gene expression by RNA interference (RNAi) significantly reduced IDGF secretion from the cells following cell growth inhibition. The IDGF gene was strongly expressed in the hemocytes, and IDGF increased the viability of the larval hemocytes. These data provide evidence that IDGF is required for the growth of NIH-Sape-4 cells and possibly for hemocyte viability.
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Affiliation(s)
- Yasuhiro Tanaka
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
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Zhang YL, Chen SS, Yang KG, Su L, Deng YC, Liu CZ. Functional expression, purification, and characterization of human Flt3 ligand in the Pichia pastoris system. Protein Expr Purif 2006; 42:246-54. [PMID: 15914030 DOI: 10.1016/j.pep.2005.04.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2004] [Revised: 03/31/2005] [Accepted: 04/01/2005] [Indexed: 11/30/2022]
Abstract
Flt3 ligand (FL) is a potent hematopoietic cytokine that affects the growth and differentiation of hematopoietic progenitor and stem cells both in vivo and in vitro. Pichia pastoris transformants secreting high-level rhFL were obtained using 'yeastern blotting' method and the expression level in liquid was about 30 mg/L. rhFL was purified to about 95% purity with overnight dialysis, filtration and an anion-exchange step. Further purification steps employing Sephacryl S-200 and reverse-phase HPLC raised the purity to over 99%. The purified rhFL possessed correct N-terminal amino acid sequence and positive Western blotting bands. SDS-PAGE and mass spectrometry analysis showed molecular weight of rhFL was about 21 and 34 kDa, suggesting that rhFL was glycosylated. The result of capillary electrophoresis showed that its pI is 3.12-4.72. Endo H deglycosylation analysis indicated that there was O-glycosylation besides N-glycosylation in rhFL secreted from P. pastoris. Bioactivity assay showed that the purified rhFL had dose-dependent expansion activity on bone marrow nucleated cells.
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Affiliation(s)
- Yan-Li Zhang
- National Laboratory of Medical Molecular Biology, Department of Biochemistry and Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing 100005, China.
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85
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Abstract
Small GTPases, which are binary switches regulating various signal transduction cascades, function not only to relay signals but also to integrate them from multiple signalling branches. For example, RalA activity is regulated by at least three signalling cascades involving Ras, Rac or PI3K (phosphoinositide 3-kinase). To untangle such complicated regulatory mechanisms, we have been developing probes for GTPases, kinases and phosphatidylinositols based on the principle of FRET (fluorescence resonance energy transfer). We demonstrated previously that, upon EGF (epidermal growth factor) stimulation, Ras activity increases diffusely in the plasma membrane, whereas RalA activity increases predominantly in lamellipodial protrusions. Here, we show that the level of PtdIns(3,4,5)P3 is increased diffusely in the plasma membrane, whereas, in the central region, the level of PtdIns(3,4)P2 is increased more in the nascent lamellipodia than in the plasma membrane. The distribution and time course of Akt activation are similar to those of increased PtdIns(3,4)P2 levels. These observations suggest that the increase in PtdIns(3,4)P2 and the subsequent activation of Akt may be responsible for the localized activation of RalA. Thus the signals from Ras and PI3K converge at the level of Ral GEFs (guanine nucleotide-exchange factors), and this convergence restricts the area of RalA activation.
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Affiliation(s)
- H Yoshizaki
- Department of Pathology and Biology of Diseases, Graduate School of Medicine, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan
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86
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Abstract
The neurobiology of pain had a notable interest in research focused on the study of neuronal plasticity development, nociceptors, molecular identity, signaling mechanism, ionic channels involved in the generation, modulation and propagation of action potential in all type of excitable cells. All the findings open the possibility for developing new therapeutic treatment. Nociceptive/inflammatory pain and neuropathic pain represent two different kinds of persistent chronic pain. We have reviewed the different mechanism suggested for the maintenance of pain, like descending nociceptive mechanism and their changes after tissue damage, including suppression and facilitation of defence behavior during pain. The role of these changes in inducing NMDA and AMPA receptors gene expression, after prolonged inflammation is emphasized by several authors. Furthermore, a relation between a persistent pain and amygdale has been shown. Molecular biology is the new frontier in the study of neurobiology of pain. Since the entire genome has been studied, we will able to find new genes involved in specific condition such as pain, because an altered gene expression can regulate neuronal activity after inflammation or tissue damage.
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Affiliation(s)
- M C Pace
- Department of Anaesthesiological, Surgical and Emergency Sciences, Second University of Naples, Naples, Italy
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87
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Abstract
PURPOSE OF REVIEW The present review summarizes evidence for several functions of neovascularization in plaque growth that sustain perfusion beyond limits of diffusion from the artery lumen and outer adventitial vasa vasorum, deposit proatherogenic plasma molecules, recruit immune cells and progenitors, and promote intraplaque hemorrhage. Recent approvals of antiangiogenesis drugs for clinical use in cancer and macular degeneration improve the feasibility of testing whether such agents inhibit plaque angiogenesis and incidental atherosclerosis. RECENT FINDINGS Improvements in large and small animal models of atherosclerosis and knowledge of the molecular regulation of angiogenesis in development and disease have advanced understanding of plaque angiogenesis. Genetic modifications of angiogenesis molecules in mouse strains susceptible to atherosclerosis provide experimental means to identify native molecules that regulate plaque angiogenesis. Studies of plaque angiogenesis are aided by micro-computed tomography techniques that image vasa vasorum anatomy in relation to the atheroma. SUMMARY Greater knowledge of plaque angiogenesis regulation is needed to design treatments that target the most critical regulatory pathways. Evolutions in angiogenesis inhibitor treatments for cancer and other diseases call for a need to understand the distinct cardiovascular profiles of different agents to rationally combine agents for optimal selectivity and efficacy in the intended vascular bed.
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Affiliation(s)
- Karen S Moulton
- Vascular Biology Program, Department of Surgery, Children's Hospital, Karp Family Research Building 11.212, 1 Blackfan Circle, Boston, MA 02115, USA.
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88
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Abstract
Neurotensin (NT) is a brain-gut tridecapeptide that functions as a neurotransmitter/neuromodulator in the central nervous system (CNS) and as an endocrine agent in the periphery. NT has numerous physiologic effects on multiple organs. This review will focus on the effects of NT as a trophic factor for normal and neoplastic tissues. In this regard, NT may act as an endocrine agent or, in some instances, in a paracrine and/or autocrine fashion. These effects appear to be mediated predominantly through the G protein-coupled high-affinity NT receptor. However, some of the trophic effects may also be through the other two receptor subtypes, particularly the NT receptor type 3, which belongs to a recently identified family of sorting receptors. The signaling pathways mediating the effects of NT are multiple but most appear to activate the ERK signaling pathway, which then activates downstream transcription factors, ultimately leading to proliferation. NT may be a useful agent to enhance the growth of normal tissues such as the small bowel mucosa during periods of gut disuse or disease and, finally, the selective targeting of NT receptor subtypes on certain cancers may offer a novel strategy in the armamentarium of cancer chemotherapeutics.
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Affiliation(s)
- B Mark Evers
- Department of Surgery, The University of Texas Medical Branch, 301 University Boulevard, Galveston, TX 77555, USA.
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89
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Abstract
Focusing on the literature of the past 15 years, we evaluate the evidence that neurotensin and neurotensin receptors participate in cancer growth and we describe possible mechanisms. In addition, we review the progress achieved in the use of neurotensin analogs to image tumors in animals and humans. These exciting advances encourage us to pursue further research and stimulate us to consider novel ideas regarding the multiple inputs to cancer growth that neurotensin might influence.
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Affiliation(s)
- Robert E Carraway
- Department of Physiology, University of Massachusetts Medical School, Worcester, MA 01655, USA.
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90
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Carlo-Stella C, Di Nicola M, Longoni P, Cleris L, Lavazza C, Milani R, Milanesi M, Magni M, Pace V, Colotta F, Avanzini MA, Formelli F, Gianni AM. Placental Growth Factor-1 Potentiates Hematopoietic Progenitor Cell Mobilization Induced by Granulocyte Colony-Stimulating Factor in Mice and Nonhuman Primates. Stem Cells 2006; 25:252-61. [PMID: 17008429 DOI: 10.1634/stemcells.2006-0020] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
The complex hematopoietic effects of placental growth factor (PlGF) prompted us to test in mice and nonhuman primates the mobilization of peripheral blood progenitor cells (PBPCs) elicited by recombinant mouse PlGF-2 (rmPlGF-2) and recombinant human PlGF-1 (rhPlGF-1). PBPC mobilization was evaluated by assaying colony-forming cells (CFCs), high-proliferative potential-CFCs (HPP-CFCs), and long-term culture-initiating cells (LTC-ICs). In mice, both rmPlGF-2 and rhPlGF-1 used as single agents failed to mobilize PBPCs, whereas the combination of rhPlGF-1 and granulocyte colony-stimulating factor (rhG-CSF) increased CFCs and LTC-ICs per milliliter of blood by four- and eightfold, respectively, as compared with rhG-CSF alone. rhPlGF-1 plus rhG-CSF significantly increased matrix metalloproteinase-9 plasma levels over rhG-CSF alone, suggesting a mechanistic explanation for rhPlGF-1/rhG-CSF synergism. In rhesus monkeys, rhPlGF-1 alone had no mobilization effect, whereas rhPlGF-1 (260 microg/kg per day) plus rhG-CSF (100 microg/kg per day) increased rhG-CSF-elicited mobilization of CFCs, HPP-CFCs, and LTC-ICs per milliliter of blood by 5-, 7-, and 15-fold, respectively. No specific toxicity was associated with the administration of rhPlGF-1 alone or in combination. In conclusion, our data demonstrate that rhPlGF-1 significantly increases rhG-CSF-elicited hematopoietic mobilization and provide a preclinical rationale for evaluating rhPlGF-1 in the clinical setting.
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Affiliation(s)
- Carmelo Carlo-Stella
- C. Gandini Bone Marrow Transplantation Unit, Istituto Nazionale Tumori, Via Venezian, 1, 20133 Milano, Italy.
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91
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Evans MK, Yu CR, Lohani A, Mahdi RM, Liu X, Trzeciak AR, Egwuagu CE. Expression of SOCS1 and SOCS3 genes is differentially regulated in breast cancer cells in response to proinflammatory cytokine and growth factor signals. Oncogene 2006; 26:1941-8. [PMID: 17001312 DOI: 10.1038/sj.onc.1209993] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.2] [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: 12/22/2022]
Abstract
DNA-hypermethylation of SOCS genes in breast, ovarian, squamous cell and hepatocellular carcinoma has led to speculation that silencing of SOCS1 and SOCS3 genes might promote oncogenic transformation of epithelial tissues. To examine whether transcriptional silencing of SOCS genes is a common feature of human carcinoma, we have investigated regulation of SOCS genes expression by IFNgamma, IGF-1 and ionizing radiation, in a normal human mammary epithelial cell line (AG11134), two breast-cancer cell lines (MCF-7, HCC1937) and three prostate cancer cell lines. Compared to normal breast cells, we observe a high level constitutive expression of SOCS2, SOCS3, SOCS5, SOCS6, SOCS7, CIS and/or SOCS1 genes in the human cancer cells. In MCF-7 and HCC1937 breast-cancer cells, transcription of SOCS1 is dramatically up-regulated by IFNgamma and/or ionizing-radiation while SOCS3 is transiently down-regulated by IFNgamma and IGF-1, suggesting that SOCS genes are not silenced in these cells by the epigenetic mechanism of DNA-hypermethylation. We further show that the kinetics of SOCS1-mediated feedback inhibition of IFNgamma signaling is comparable to normal breast cells, indicating that the SOCS1 protein in breast-cancer cells is functional. We provide direct evidence that STAT3 pathways are constitutively activated in MCF-7 and HCC1937 cells and may drive the aberrant persistent activation of SOCS genes in breast-cancer cells. Our data therefore suggest that elevated expression of SOCS genes is a specific lesion of breast-cancer cells that may confer resistance to proinflammatory cytokines and trophic factors, by shutting down STAT1/STAT5 signaling that mediate essential functions in the mammary gland.
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Affiliation(s)
- M K Evans
- Laboratory of Cellular and Molecular Biology, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA.
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92
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Wallace MJ, Thiel AM, Lines AM, Polglase GR, Sozo F, Hooper SB. Role of platelet-derived growth factor-B, vascular endothelial growth factor, insulin-like growth factor-II, mitogen-activated protein kinase and transforming growth factor-beta1 in expansion-induced lung growth in fetal sheep. Reprod Fertil Dev 2006; 18:655-65. [PMID: 16930512 DOI: 10.1071/rd05163] [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: 12/13/2005] [Accepted: 03/21/2006] [Indexed: 01/23/2023] Open
Abstract
Increased fetal lung expansion induces lung growth, cell differentiation and extracellular matrix remodelling, although the mechanisms involved are unknown. Platelet-derived growth factor (PDGF)-B, vascular endothelial growth factor (VEGF) and insulin-like growth factor (IGF)-II are mitogens activating the mitogen-activated protein kinase (MAPK) pathway, whereas transforming growth factor (TGF)-beta1 induces differentiation and extracellular matrix remodelling. In the present study, we investigated the mRNA levels of PDGF-B, VEGF, IGF-II and TGF-beta1, as well as active MAPK levels, during increased fetal lung expansion induced by tracheal obstruction (TO) in sheep for 0 (controls), 36 h or 2, 4, or 10 days (n = 5 in each group). The 3.7-kb VEGF transcript increased by 30% (P < 0.05) at 36 h TO. The expression of PDGF-B decreased by approximately 25% (P < 0.01) at 2-10 days TO. In contrast, TGF-beta1 mRNA increased by 96% (P < 0.05) at 10 days TO, when bioactive TGF-beta1 decreased by 55% (P < 0.05). Insulin-like growth factor-II mRNA tended to increase at 10 days TO (37% above controls; P = 0.07), whereas mRNA for its receptor, IGF1R, was reduced by TO. There was no change in active MAPK levels preceding or at the time of a TO-induced 800% increase in cell proliferation. We conclude that VEGF is likely to promote expansion-induced endothelial cell proliferation, but the mechanisms underlying expansion-induced proliferation of fibroblasts and alveolar epithelial cells are unlikely to be mediated by increases in PDGF-B or IGF-II expression or activation of the MAPK pathway.
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Affiliation(s)
- Megan J Wallace
- Department of Physiology, Monash University, Vic. 3800, Australia.
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93
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Abstract
Cell survival has been closely linked to both trophic growth factor signaling and cellular metabolism. Such couplings have obvious physiologic and pathophysiologic implications, but their underlying molecular bases remain incompletely defined. As a common mediator of both the metabolic and anti-apoptotic effects of growth factors, the serine/threonine kinase Akt - also known as protein kinase B or PKB - is capable of regulating and coordinating these inter-related processes. The glucose dependence of the antiapoptotic effects of growth factors and Akt plus a strong correlation between Akt-regulated mitochondrial hexokinase association and apoptotic susceptibility suggest a major role for hexokinases in these effects. Mitochondrial hexokinases catalyse the first obligatory step of glucose metabolism and directly couple extramitochondrial glycolysis to intramitochondrial oxidative phosphorylation, and are thus well suited to play this role. The ability of Akt to regulate energy metabolism appears to have evolutionarily preceded the capacity to control cell survival. This suggests that Akt-dependent metabolic regulatory functions may have given rise to glucose-dependent antiapoptotic effects that evolved as an adaptive sensing system involving hexokinases and serve to ensure mitochondrial homeostasis, thereby coupling metabolism to cell survival. We hypothesize that the enlistment of Akt and hexokinase in the control of mammalian cell apoptosis evolved as a response to the recruitment of mitochondria to the apoptotic cascade. The central importance of mitochondrial hexokinases in cell survival also suggests that they may represent viable therapeutic targets in cancer.
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Affiliation(s)
- R B Robey
- Research and Development Service, White River Junction VA Medical Center, White River Junction, VT 05009-0001, USA
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94
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95
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Abstract
Pituitary tumors exhibit a spectrum of biology, with variable growth and hormonal behaviors. They therefore provide an opportunity to examine pathogenetic mechanisms that underlie the neoplastic process. These include alterations in hormone regulation, growth-factor stimulation, cell-cycle control and cell-stromal interactions that result from genetic mutations or epigenetic disruption of gene expression. Mouse models have validated the roles of these alterations, which can be targets for the development of therapies that can manage these lesions. These therapies are increasingly recognized as critical for quality of life.
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Affiliation(s)
- Shereen Ezzat
- The Freeman Centre for Endocrine Oncology, Mount Sinai Hospital, Toronto, Ontario, Canada
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96
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Abstract
Regeneration that takes place in the human body is limited throughout life. Therefore, when organs are irreparably damaged, they are usually replaced with an artificial device or donor organ. The term "regenerative medicine" covers the restoration or replacement of cells, tissues, and organs. Stem cells play a major role in regenerative medicine by providing the way to repopulate organs damaged by disease. Stem cells have the ability to self renew and to regenerate cells of diverse lineages within the tissue in which they reside. Stem cells could originate from embryos or adult tissues. Growth factors are proteins that may act locally or systemically to affect the growth of cells in several ways. Various cell activities, including division, are influenced by growth factors. Cytokines are a family of low-molecular-weight proteins that are produced by numerous cell types and are responsible for regulating the immune response, inflammation, tissue remodeling and cellular differentiation. Target cells of growth factors and cytokines are mesenchymal, epithelial and endothelial cells. These molecules frequently have overlapping activities and can act in an autocrine or paracrine fashion. A complex network of growth factors and cytokines guides cellular differentiation and regeneration in all organs and tissues. The aim of this paper is to review the role of growth factors and cytokines in different organs or systems and explore their therapeutic application in regenerative medicine. The role of stem cells combined with growth factors and cytokines in the regeneration of vascular and hematopoietic, neural, skeletal, pancreatic, periodontal, and mucosal tissue is reviewed. There is evidence that supports the use of growth factors and cytokines in the treatment of neurological diseases, diabetes, cardiovascular disease, periodontal disease, cancer and its complication, oral mucositis. After solving the ethical issues and establishing clear and reasonable regulations, regenerative medicine through stem cell application combined with specific growth factors and cytokines will have great potential in curing a variety of human diseases.
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Affiliation(s)
- Effie Ioannidou
- Department of Periodontology, School of Dental Medicine, University of Connecticut Health Center, USA.
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97
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Abstract
The human hair follicle is a unique appendage which results from epithelio-mesenchymal interactions initiated around the 3rd month of development. This appendage has a very complex structure, with more than 20 different cell types distributed into 6 main compartments, namely the connective tissue sheath, the dermal papilla, the outer root sheath, the inner root sheath, the shaft and the sebaceous gland. The pigmentation unit, responsible for hair color, is made of fully active melanocytes located on top of the dermal papilla. This complex appendage has a unique behavior in mammals since, after a hair production phase, it involutes in situ before entering a resting phase after which it renews in a cyclical but stochastic fashion, out of a double reservoir of pluripotent stem cells also to able regenerate epidermis. The pigmentation unit also renews in a cyclical fashion, out of a melanocyte progenitor reservoir which progressively declines with time, provoking the hair whitening process. Finally, the shape of the hair shaft is programmed from the bulb. The hair follicle thus behaves as a fully autonomous skin appendage with its own hormonal control, its own autocrine and paracrine network, its own cycle, appearing as an incredibly complex and stable structure which summarizes the main rules of tissue homeostasis.
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Affiliation(s)
- Bruno A Bernard
- L'OREAL Recherche, Centre C. Zviak, 90, rue du Général Roguet, 92110 Clichy
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98
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Abstract
The cardiovascular system plays a critical role in vertebrate development and homeostasis. Vascular development is a highly organized sequence of events that requires the correct spatial and temporal expression of specific sets of genes leading to the development of a primary vascular network. There have been intensive efforts to determine the molecular mechanisms regulating vascular growth and development, and much of the rationale for this has stemmed from the increasing clinical importance and therapeutic potential of modulating vascular formation during various disease states.
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Affiliation(s)
- Domenico Ribatti
- Department of Human Anatomy and Histology, University of Bari Medical School, Italy.
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99
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Katsuma S, Horie S, Daimon T, Iwanaga M, Shimada T. In vivo and in vitro analyses of a Bombyx mori nucleopolyhedrovirus mutant lacking functional vfgf. Virology 2006; 355:62-70. [PMID: 16904150 DOI: 10.1016/j.virol.2006.07.008] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2006] [Revised: 06/12/2006] [Accepted: 07/11/2006] [Indexed: 11/21/2022]
Abstract
All lepidopteran baculovirus genomes sequenced to date encode a viral fibroblast growth factor homolog (vfgf), suggesting that vfgf may play an important role in the infection cycle of lepidopteran baculoviruses. Here, we describe the characterization of a Bombyx mori nucleopolyhedrovirus (BmNPV) mutant lacking functional vfgf. We constructed a vfgf deletion mutant (BmFGFD) and characterized it in BmN cells and B. mori larvae. We observed that budded virus (BV) production was reduced in BmFGFD-infected BmN cells and B. mori larvae. The larval bioassays also revealed that deletion of vfgf did not reduce the infectivity; however, the mutant virus did take 20 h longer to kill B. mori larvae than wild-type BmNPV, when tested either by BV injection or by polyhedrin-inclusion body ingestion. These results suggest that BmNPV vfgf is involved in efficient virus production in BmN cells and B. mori larvae.
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Affiliation(s)
- Susumu Katsuma
- Department of Agricultural and Environmental Biology, Graduate School of Agricultural and Life Sciences, University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan.
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100
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Clark AG, Chen S, Zhang H, Brady GF, Ungewitter EK, Bradley JK, Sackey FN, Foster MH. Multifunctional regulators of cell growth are differentially expressed in anergic murine B cells. Mol Immunol 2006; 44:1274-85. [PMID: 16890292 DOI: 10.1016/j.molimm.2006.06.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [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] [Received: 05/13/2006] [Revised: 06/05/2006] [Accepted: 06/08/2006] [Indexed: 10/24/2022]
Abstract
Defective anergy is a major cause of failed tolerance and is amenable to therapeutic manipulation. To better define the molecular basis of anergy in B cells tolerized by matrix self-antigen, we used complementary approaches of representational difference analysis (RDA) and microarray to identify genes differentially transcribed in anergic as compared to non-tolerant B cells isolated from a well-characterized murine autoantibody transgenic model. Forty RDA clones representing 16 genes were isolated from receptor-stimulated B cells and independently confirmed as differentially expressed in tolerant cells using custom microarray, dot blotting and/or quantitative PCR. Differential expression was conserved in tolerant cells from two different transgenic founder lineages and from two genetically disparate backgrounds. Prominent among recovered gene fragments were genes encoding multifunctional proteins not previously implicated in B cell biology, but with roles in biologic processes fundamental to the tolerance phenotype, including cell growth, proliferation and differentiation. RDA also identified a novel transcript not previously reported in nucleic acid databases. To further explore dependence on receptor stimulation and to identify additional genes, commercial oligonucleotide arrays were probed with labeled B cell transcripts and analyzed for genes differentially expressed in resting as well as stimulated cells and in both B6 and MRL mouse strains. Arrays identified differential expression of a subset of RDA genes as well as 46 additional genes, including subsets engaged in signal transduction, transcriptional regulation, cell growth and apoptosis. Immunoblotting confirmed differential protein expression for galectin-3 and galectin-1, two interactive members of the galectin family, suggesting a novel role for galectins as regulators of immune tolerance.
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Affiliation(s)
- Amy G Clark
- Department of Medicine, Durham Veterans Affairs Medical Center, NC, USA
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