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Sample records for activated transforming growth

  1. Cells transformed by murine herpesvirus 68 (MHV-68) release compounds with transforming and transformed phenotype suppressing activity resembling growth factors.

    PubMed

    Šupolíková, M; Staňová, A Vojs; Kúdelová, M; Marák, J; Zelník, V; Golais, F

    2015-12-01

    In this study, we investigated the medium of three cell lines transformed with murine herpesvirus 68 (MHV-68) in vitro and in vivo, 68/HDF, 68/NIH3T3, and S11E, for the presence of compounds resembling growth factors of some herpesviruses which have displayed transforming and transformed phenotype suppressing activity in normal and tumor cells. When any of spent medium was added to cell culture we observed the onset of transformed phenotype in baby hamster kidney cells (BHK-21) cells and transformed phenotype suppressing activity in tumor human epithelial cells (HeLa). In media tested, we have identified the presence of putative growth factor related to MHV-68 (MHGF-68). Its bivalent properties have been blocked entirely by antisera against MHV-68 and two monoclonal antibodies against glycoprotein B (gB) of MHV-68 suggesting viral origin of MHGF-68. The results of initial efforts to separate MHGF-68 on FPLC Sephadex G15 column in the absence of salts revealed the loss of its transforming activity but transformed phenotype suppressing activity retained. On the other hand, the use of methanol-water mobile phase on RP-HPLC C18 column allowed separation of MHGF-68 to two compounds. Both separated fractions, had only the transforming activity to normal cells. Further experiments exploring the nature and the structure of hitherto unknown MHGF-68 are now in the progress to characterize its molecular and biological properties. PMID:26666191

  2. Sustained activation of fibroblast transforming growth factor-beta/Smad signaling in a murine model of scleroderma.

    PubMed

    Takagawa, Shinsuke; Lakos, Gabriella; Mori, Yasuji; Yamamoto, Toshiyuki; Nishioka, Kiyoshi; Varga, John

    2003-07-01

    Transforming growth factor-beta is responsible for triggering a cascade of events leading to fibrosis in scleroderma. The Smads are intracellular signal transducers recently shown to mediate fibroblast activation and other profibrotic responses elicited by transforming growth factor-betain vitro. To understand better the involvement of Smads in the pathogenesis of fibrosis, we examined Smad expression and activation in situ in a murine model of scleroderma. Bleomycin injections induced striking dermal infiltration with macrophages by 3 d, and progressive fibrosis by 2 wk. Infiltrating macrophages and resident fibroblasts expressed Smad3, the positive mediator for transforming growth factor-beta responses. Importantly, in bleomycin-injected skin, fibroblasts showed predominantly nuclear localization of Smad3 and intense staining for phospho-Smad2/3. Furthermore, phosphorylated Smad2/3 in fibroblasts was detected even after the resolution of inflammation. Expression of Smad7, the endogenous inhibitor of transforming growth factor-beta/Smad signaling, was strongly induced in dermal cells by transforming growth factor-beta, but not by bleomycin injections. Collectively, these results indicate that bleomycin-induced murine scleroderma is associated with rapid and sustained induction of transforming growth factor-beta/Smad signaling in resident dermal fibroblasts. Despite apparent activation of the intracellular transforming growth factor-beta signaling pathway in the lesional dermis, the expression of transforming growth factor-beta-inducible Smad7 was not upregulated. In light of the critical function of Smad7 as an endogenous inhibitor of Smad signaling that restricts the duration and magnitude of transforming growth factor-beta responses, and as a mediator of apoptosis, relative Smad7 deficiency observed in the present studies may account for sustained activation of transforming growth factor-beta/Smad signaling in lesional tissues. These findings raise the

  3. Immunocytochemical Localization of Latent Transforming Growth Factor-B1 Activation by Stimulated Macrophages

    SciTech Connect

    Chong, Hyonkyong; Vodovotz, Yoram; Cox, G.W.; Barcellos-Hoff, M.H.

    1998-09-22

    Transforming growth factor-{beta}1 (TGF-{beta}) is secreted in a latent form consisting of mature TGF-{beta} noncovalently associated with its amino-terminal propeptide, which is called latency associated peptide (LAP). Biological activity depends upon the release of TGF-{beta} from the latent complex following extracellular activation, which appears to be the key regulatory mechanism controlling TGF-{beta} action. We have identified two events associated with latent TGF-{beta} (LTGF-{beta}) activation in vivo: increased immunoreactivity of certain antibodies that specifically detect TGF-{beta} concomitant with decreased immunoreactivity of antibodies to LAP. Macrophages stimulated in vitro with interferon-{gamma} and lipopolysaccharide reportedly activate LTGF-{beta} via cell membrane-bound protease activity. We show through dual immunostaining of paraformaldehyde-fixed macrophages that such physiological TGF-{beta} activation is accompanied by a loss of LAP immunoreactivity with concomitant revelation of TGF-{beta} epitopes. The induction of TGF-{beta} immunoreactivity colocalized with immunoreactive betaglycan/RIII in activated macrophages, suggesting that LTGF-{beta} activation occurs on the cell surface. Confocal microscopy of metabolically active macrophages incubated with antibodies to TGF-{beta} and betaglycan/RIII prior to fixation supported the localization of activation to the cell surface. The ability to specifically detect and localize LTGF-{beta} activation provides an important tool for studies of its regulation.

  4. Immunocytochemical localization of latent transforming growth factor-beta1 activation by stimulated macrophages

    NASA Technical Reports Server (NTRS)

    Chong, H.; Vodovotz, Y.; Cox, G. W.; Barcellos-Hoff, M. H.; Chatterjee, A. (Principal Investigator)

    1999-01-01

    Transforming growth factor-beta1 (TGF-beta) is secreted in a latent form consisting of mature TGF-beta noncovalently associated with its amino-terminal propeptide, which is called latency associated peptide (LAP). Biological activity depends upon the release of TGF-beta from the latent complex following extracellular activation, which appears to be the key regulatory mechanism controlling TGF-beta action. We have identified two events associated with latent TGF-beta (LTGF-beta) activation in vivo: increased immunoreactivity of certain antibodies that specifically detect TGF-beta concomitant with decreased immunoreactivity of antibodies to LAP. Macrophages stimulated in vitro with interferon-gamma and lipopolysaccharide reportedly activate LTGF-beta via cell membrane-bound protease activity. We show through dual immunostaining of paraformaldehyde-fixed macrophages that such physiological TGF-beta activation is accompanied by a loss of LAP immunoreactivity with concomitant revelation of TGF-beta epitopes. The induction of TGF-beta immunoreactivity colocalized with immunoreactive betaglycan/RIII in activated macrophages, suggesting that LTGF-beta activation occurs on the cell surface. Confocal microscopy of metabolically active macrophages incubated with antibodies to TGF-beta and betaglycan/RIII prior to fixation supported the localization of activation to the cell surface. The ability to specifically detect and localize LTGF-beta activation provides an important tool for studies of its regulation.

  5. Lysyl oxidase binds transforming growth factor-beta and regulates its signaling via amine oxidase activity.

    PubMed

    Atsawasuwan, Phimon; Mochida, Yoshiyuki; Katafuchi, Michitsuna; Kaku, Masaru; Fong, Keith S K; Csiszar, Katalin; Yamauchi, Mitsuo

    2008-12-01

    Lysyl oxidase (LOX), an amine oxidase critical for the initiation of collagen and elastin cross-linking, has recently been shown to regulate cellular activities possibly by modulating the functions of growth factors. In this study, we investigated the interaction between LOX and transforming growth factor-beta1 (TGF-beta1), a potent growth factor abundant in bone, the effect of LOX on TGF-beta1 signaling, and its potential mechanism. The specific binding between mature LOX and mature TGF-beta1 was demonstrated by immunoprecipitation and glutathione S-transferase pulldown assay in vitro. Both proteins were colocalized in the extracellular matrix in an osteoblastic cell culture system, and the binding complex was identified in the mineral-associated fraction of bone matrix. Furthermore, LOX suppressed TGF-beta1-induced Smad3 phosphorylation likely through its amine oxidase activity. The data indicate that LOX binds to mature TGF-beta1 and enzymatically regulates its signaling in bone and thus may play an important role in bone maintenance and remodeling. PMID:18835815

  6. Redox-mediated activation of latent transforming growth factor-beta 1

    NASA Technical Reports Server (NTRS)

    Barcellos-Hoff, M. H.; Dix, T. A.; Chatterjee, A. (Principal Investigator)

    1996-01-01

    Transforming growth factor beta 1 (TGF beta) is a multifunctional cytokine that orchestrates response to injury via ubiquitous cell surface receptors. The biological activity of TGF beta is restrained by its secretion as a latent complex (LTGF beta) such that activation determines the extent of TGF beta activity during physiological and pathological events. TGF beta action has been implicated in a variety of reactive oxygen-mediated tissue processes, particularly inflammation, and in pathologies such as reperfusion injury, rheumatoid arthritis, and atherosclerosis. It was recently shown to be rapidly activated after in vivo radiation exposure, which also generates reactive oxygen species (ROS). In the present studies, the potential for redox-mediated LTGF beta activation was investigated using a cell-free system in which ROS were generated in solution by ionizing radiation or metal ion-catalyzed ascorbate reaction. Irradiation (100 Gray) of recombinant human LTGF beta in solution induced 26% activation compared with that elicited by standard thermal activation. Metal-catalyzed ascorbate oxidation elicited extremely efficient recombinant LTGF beta activation that matched or exceeded thermal activation. The efficiency of ascorbate activation depended on ascorbate concentrations and the presence of transition metal ions. We postulate that oxidation of specific amino acids in the latency-conferring peptide leads to a conformation change in the latent complex that allows release of TGF beta. Oxidative activation offers a novel route for the involvement of TGF beta in tissue processes in which ROS are implicated and endows LTGF beta with the ability to act as a sensor of oxidative stress and, by releasing TGF beta, to function as a signal for orchestrating the response of multiple cell types. LTGF beta redox sensitivity is presumably directed toward recovery of homeostasis; however, oxidation may also be a mechanism of LTGF beta activation that can be deleterious during

  7. Redox-mediated activation of latent transforming growth factor-beta 1.

    PubMed

    Barcellos-Hoff, M H; Dix, T A

    1996-09-01

    Transforming growth factor beta 1 (TGF beta) is a multifunctional cytokine that orchestrates response to injury via ubiquitous cell surface receptors. The biological activity of TGF beta is restrained by its secretion as a latent complex (LTGF beta) such that activation determines the extent of TGF beta activity during physiological and pathological events. TGF beta action has been implicated in a variety of reactive oxygen-mediated tissue processes, particularly inflammation, and in pathologies such as reperfusion injury, rheumatoid arthritis, and atherosclerosis. It was recently shown to be rapidly activated after in vivo radiation exposure, which also generates reactive oxygen species (ROS). In the present studies, the potential for redox-mediated LTGF beta activation was investigated using a cell-free system in which ROS were generated in solution by ionizing radiation or metal ion-catalyzed ascorbate reaction. Irradiation (100 Gray) of recombinant human LTGF beta in solution induced 26% activation compared with that elicited by standard thermal activation. Metal-catalyzed ascorbate oxidation elicited extremely efficient recombinant LTGF beta activation that matched or exceeded thermal activation. The efficiency of ascorbate activation depended on ascorbate concentrations and the presence of transition metal ions. We postulate that oxidation of specific amino acids in the latency-conferring peptide leads to a conformation change in the latent complex that allows release of TGF beta. Oxidative activation offers a novel route for the involvement of TGF beta in tissue processes in which ROS are implicated and endows LTGF beta with the ability to act as a sensor of oxidative stress and, by releasing TGF beta, to function as a signal for orchestrating the response of multiple cell types. LTGF beta redox sensitivity is presumably directed toward recovery of homeostasis; however, oxidation may also be a mechanism of LTGF beta activation that can be deleterious during

  8. Immunohistochemical detection of active transforming growth factor-beta in situ using engineered tissue

    NASA Technical Reports Server (NTRS)

    Barcellos-Hoff, M. H.; Ehrhart, E. J.; Kalia, M.; Jirtle, R.; Flanders, K.; Tsang, M. L.; Chatterjee, A. (Principal Investigator)

    1995-01-01

    The biological activity of transforming growth factor-beta 1 (TGF-beta) is governed by dissociation from its latent complex. Immunohistochemical discrimination of active and latent TGF-beta could provide insight into TGF-beta activation in physiological and pathological processes. However, evaluation of immunoreactivity specificity in situ has been hindered by the lack of tissue in which TGF-beta status is known. To provide in situ analysis of antibodies to differentiate between these functional forms, we used xenografts of human tumor cells modified by transfection to overexpress latent TGF-beta or constitutively active TGF-beta. This comparison revealed that, whereas most antibodies did not differentiate between TGF-beta activation status, the immunoreactivity of some antibodies was activation dependent. Two widely used peptide antibodies to the amino-terminus of TGF-beta, LC(1-30) and CC(1-30) showed marked preferential immunoreactivity with active TGF-beta versus latent TGF-beta in cryosections. However, in formalin-fixed, paraffin-embedded tissue, discrimination of active TGF-beta by CC(1-30) was lost and immunoreactivity was distinctly extracellular, as previously reported for this antibody. Similar processing-dependent extracellular localization was found with a neutralizing antibody raised to recombinant TGF-beta. Antigen retrieval recovered cell-associated immunoreactivity of both antibodies. Two antibodies to peptides 78-109 showed mild to moderate preferential immunoreactivity with active TGF-beta only in paraffin sections. LC(1-30) was the only antibody tested that discriminated active from latent TGF-beta in both frozen and paraffin-embedded tissue. Thus, in situ discrimination of active versus latent TGF-beta depends on both the antibody and tissue preparation. We propose that tissues engineered to express a specific form of a given protein provide a physiological setting in which to evaluate antibody reactivity with specific functional forms of a

  9. Overexpressed homeobox B9 regulates oncogenic activities by transforming growth factor-β1 in gliomas

    SciTech Connect

    Fang, Liping; Xu, Yinghui; Zou, Lijuan

    2014-03-28

    Highlights: • HOXB9 is overexpressed in gliomas. • HOXB9 over expression had shorter survival time than down expression in gliomas. • HOXB9 stimulated the proliferation, migration and sphere formation of glioma cells. • Activation of TGF-β1 contributed to HOXB9-induced oncogenic activities. - Abstract: Glioma is the leading cause of deaths related to tumors in the central nervous system. The mechanisms of gliomagenesis remain elusive to date. Homeobox B9 (HOXB9) has a crucial function in the regulation of gene expression and cell survival, but its functions in glioma formation and development have yet to be elucidated. This study showed that HOXB9 expression in glioma tissues was significantly higher than that in nontumor tissues. Higher HOXB9 expression was also significantly associated with advanced clinical stage in glioma patients. HOXB9 overexpression stimulated the proliferation, migration, and sphere formation of glioma cells, whereas HOXB9 knockdown elicited an opposite effect. HOXB9 overexpression also increased the tumorigenicity of glioma cells in vivo. Moreover, the activation of transforming growth factor-β1 contributed to HOXB9-induced oncogenic activities. HOXB9 could be used as a predictable biomarker to be detected in different pathological and histological subtypes in glioma for diagnosis or prognosis.

  10. Berbamine enhances the antineoplastic activity of gemcitabine in pancreatic cancer cells by activating transforming growth factor-β/Smad signaling.

    PubMed

    Jin, Xiaoli; Wu, Yulian

    2014-05-01

    Drug-resistance to gemcitabine chemotherapy in pancreatic cancer is still an unsolved problem. Combinations of other chemotherapy drugs with gemcitabine have been shown to increase the efficacy of gemcitabine-based treatment. In this study, the effect of berbamine on the antitumor activity of gemcitabine was evaluated in human pancreatic cancer cell lines Bxpc-3 and Panc-1, and the underlying mechanisms were explored. Our results demonstrated that berbamine exhibited a time- and dose-dependent inhibitory effect in the pancreatic cancer cell lines. Berbamine enhanced gemcitabine-induced cell growth inhibition and apoptosis in these cells. Combined treatment of berbamine and gemcitabine resulted in down-regulation of anti-apoptotic proteins (Bcl-2, Bcl-xL) and up-regulation of pro-apoptotic proteins (Bax, Bid). More importantly, berbamine treatment in combination with gemcitabine activated the transforming growth factor-β/Smad (TGF-β/Smad) signaling pathway, as a result of a decrease in Smad7 and an increase in transforming growth factor-β receptor II (TβRII) expression. Changes in downstream targets of Smad7, such as up-regulation of p21 and down-regulation of c-Myc and Cyclin D1 were also observed. Therefore, berbamine could enhance the antitumor activity of gemcitabine by inhibiting cell growth and inducing apoptosis, possibly through the regulation of the expression of apoptosis-related proteins and the activation of TGF-β/Smad signaling pathway. Our study indicates that berbamine may be a promising candidate to be used in combination with gemcitabine for pancreatic cancer treatment. PMID:24619961

  11. Diosgenin attenuates hepatic stellate cell activation through transforming growth factor-β/Smad signaling pathway

    PubMed Central

    Xie, Wei-Lin; Jiang, Rong; Shen, Xiao-Lu; Chen, Zhi-Yu; Deng, Xiao-Ming

    2015-01-01

    Activation of hepatic stellate cells (HSC) plays a pivotal role in the development of hepatic fibrosis. Transforming growth factor-β1 (TGF-β1) is considered to be the main stimuli factor responsible for the activation of HSC. Diosgenin is a steroidal saponin found in several plants including Solanum and Dioscorea species, and it inhibited high glucose-induced renal tubular fibrosis. However, the effects of diosgenin against hepatic fibrosis remain elusive. Therefore, in this study, we investigated the effects of diosgenin on TGF-β1-induced HSCs and elucidate the possible mechanism of its anti-fibrotic effect. Our results demonstrated that diosgenin inhibited TGF-β1-induced HSC proliferation, reduced the expression of collagen I and α-smooth muscle actin (α-SMA), as well as the expression of TGF-β receptor I (TGF-β RI) and II. Moreover, diosgenin suppressed TGF-β1-induced phosphorylation of Smad3 in HSCs. In conclusion, our data demonstrate that diosgenin inhibited HSC-T6 cell proliferation and activation, at least in part, via the TGF-β1/Smad signaling pathway. These results provide that diosgenin may have potential to treat liver fibrosis. PMID:26884947

  12. Diosgenin attenuates hepatic stellate cell activation through transforming growth factor-β/Smad signaling pathway.

    PubMed

    Xie, Wei-Lin; Jiang, Rong; Shen, Xiao-Lu; Chen, Zhi-Yu; Deng, Xiao-Ming

    2015-01-01

    Activation of hepatic stellate cells (HSC) plays a pivotal role in the development of hepatic fibrosis. Transforming growth factor-β1 (TGF-β1) is considered to be the main stimuli factor responsible for the activation of HSC. Diosgenin is a steroidal saponin found in several plants including Solanum and Dioscorea species, and it inhibited high glucose-induced renal tubular fibrosis. However, the effects of diosgenin against hepatic fibrosis remain elusive. Therefore, in this study, we investigated the effects of diosgenin on TGF-β1-induced HSCs and elucidate the possible mechanism of its anti-fibrotic effect. Our results demonstrated that diosgenin inhibited TGF-β1-induced HSC proliferation, reduced the expression of collagen I and α-smooth muscle actin (α-SMA), as well as the expression of TGF-β receptor I (TGF-β RI) and II. Moreover, diosgenin suppressed TGF-β1-induced phosphorylation of Smad3 in HSCs. In conclusion, our data demonstrate that diosgenin inhibited HSC-T6 cell proliferation and activation, at least in part, via the TGF-β1/Smad signaling pathway. These results provide that diosgenin may have potential to treat liver fibrosis. PMID:26884947

  13. Protection of transforming growth factor-beta 1 activity by heparin and fucoidan.

    PubMed

    McCaffrey, T A; Falcone, D J; Vicente, D; Du, B; Consigli, S; Borth, W

    1994-04-01

    The transforming growth factor-beta (TGF-beta) family of proteins exert diverse and potent effects on proliferation, differentiation, and extracellular matrix synthesis. However, relatively little is known about the stability or processing of endogenous TGF-beta activity in vitro or in vivo. Our previous work indicated that 1) TGF-beta 1 has strong heparin-binding properties that were not previously recognized because of neutralization by iodination, and 2) heparin, and certain other polyanions, could block the binding of TGF-beta 1 to alpha 2-macroglobulin (alpha 2-M). The present studies investigated the influence of heparin-like molecules on the stability of the TGF-beta 1 signal in the pericellular environment. The results indicate that heparin and fucoidan, a naturally occurring sulfated L-fucose polymer, suppress the formation of an initial non-covalent interaction between 125I-TGF-beta 1 and activated alpha 2-M. Electrophoresis of 125I-TGF-beta 1 showed that fucoidan protects TGF-beta 1 from proteolytic degradation by plasmin and trypsin. While plasmin caused little, if any, activation of latent TGF-beta derived from vascular smooth muscle cells (SMC), plasmin degraded acid-activated TGF-beta, and purified TGF-beta 1, and this degradation was inhibited by fucoidan. In vitro, heparin and fucoidan tripled the half-life of 125I-TGF-beta 1 and doubled the amount of cell-associated 125I-TGF-beta 1. Consistent with this protective effect, heparin- and fucoidan-treated SMC demonstrated elevated levels of active, but not latent, TGF-beta activity. PMID:7511146

  14. Growth habit and photo-synthetic activity of shoot cultures of Medicago sativa L. transformed with the oryzacystatin II gene

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In vitro maintained shoot cultures of alfalfa (Medicago sativa L. cv. Zajeÿarska 83) that were transformed with the oryzacystatin II (OCII) gene and propagated on growth regulator-free medium were subjected to analysis of morphological characteristics and photosynthetic activity. The most striking f...

  15. GAP JUNCTION COMMUNICATION MEDIATES TRANSFORMING GROWTH FACTOR-BETA ACTIVATION AND ENDOTHELIAL-INDUCED MURAL CELL DIFFERENTIATION

    Technology Transfer Automated Retrieval System (TEKTRAN)

    During blood vessel assembly, endothelial cells recruit mesenchymal progenitors and induce their differentiation into mural cells via contact-dependent transforming growth factor-beta (TGF-beta) activation. We investigated whether gap junction channels are formed between endothelial cells and recrui...

  16. Urinary active transforming growth factor β in feline chronic kidney disease.

    PubMed

    Lawson, J S; Syme, H M; Wheeler-Jones, C P D; Elliott, J

    2016-08-01

    The cytokine transforming growth factor beta 1 (TGF-β1) has been widely implicated in the development and progression of renal fibrosis in chronic kidney disease (CKD) in humans and in experimental models. The aims of this study were to assess the association between urinary active TGF-β1 and (a) development of CKD in a cross-sectional study, (b) deterioration of renal function over 1 year in a longitudinal study, and (c) renal histopathological parameters in cats. A human active TGF-β1 ELISA was validated for use in feline urine. Cross-sectional analysis revealed no significant difference in urinary active TGF-β1:creatinine ratio (aTGF-β1:UCr) between groups with differing renal function. Longitudinally, non-azotaemic cats that developed CKD demonstrated a significant (P = 0.028) increase in aTGF-β1:UCr approximately 6 months before the development of azotaemia, which remained elevated (P = 0.046) at diagnosis (approximately 12 months prior, 8.4 pg/mg; approximately 6 months prior, 22.2 pg/mg; at CKD diagnosis, 24.6 pg/mg). In the histopathology study, aTGF-β1:UCr was significantly higher in cats with moderate (P = 0.02) and diffuse (P = 0.005) renal fibrosis than in cats without fibrosis. Cats with moderate renal inflammation had significantly higher urinary active aTGF-β1 concentrations than cats with mild (P = 0.035) or no inflammatory change (P = 0.004). The parameter aTGF-β1:UCr was independently associated with Log urine protein:creatinine ratio in a multivariable analysis of clinicopathological parameters and interstitial fibrosis score in a multivariable analysis of histopathological features. These results suggest that urinary aTGF-β1 reflects the severity of renal pathology. Increases in urinary aTGF-β1 followed longitudinally in individual cats may indicate the development of CKD. PMID:27387717

  17. Platelet-derived growth factor and transforming growth factor-beta enhance tissue repair activities by unique mechanisms.

    PubMed

    Pierce, G F; Mustoe, T A; Lingelbach, J; Masakowski, V R; Griffin, G L; Senior, R M; Deuel, T F

    1989-07-01

    Platelet-derived growth factor (PDGF) and transforming growth factor-beta (TGF-beta) markedly potentiate tissue repair in vivo. In the present experiments, both in vitro and in vivo responses to PDGF and TGF-beta were tested to identify mechanisms whereby these growth factors might each enhance the wound-healing response. Recombinant human PDGF B-chain homodimers (PDGF-BB) and TGF-beta 1 had identical dose-response curves in chemotactic assays with monocytes and fibroblasts as the natural proteins from platelets. Single applications of PDGF-BB (2 micrograms, 80 pmol) and TGF-beta 1 (20 micrograms, 600 pmol) were next applied to linear incisions in rats and each enhanced the strength required to disrupt the wounds at 5 d up to 212% of paired control wounds. Histological analysis of treated wounds demonstrated an in vivo chemotactic response of macrophages and fibroblasts to both PDGF-BB and to TGF-beta 1 but the response to TGF-beta 1 was significantly less than that observed with PDGF-BB. Marked increases of procollagen type I were observed by immunohistochemical staining in fibroblasts in treated wounds during the first week. The augmented breaking strength of TGF-beta 1 was not observed 2 and 3 wk after wounding. However, the positive influence of PDGF-BB on wound breaking strength persisted through the 7 wk of testing. Furthermore, PDGF-BB-treated wounds had persistently increased numbers of fibroblasts and granulation tissue through day 21, whereas the enhanced cellular influx in TGF-beta 1-treated wounds was not detectable beyond day 7. Wound macrophages and fibroblasts from PDGF-BB-treated wounds contained sharply increased levels of immunohistochemically detectable intracellular TGF-beta. Furthermore, PDGF-BB in vitro induced a marked, time-dependent stimulation of TGF-beta mRNA levels in cultured normal rat kidney fibroblasts. The results suggest that TGF-beta transiently attracts fibroblasts into the wound and may stimulate collagen synthesis directly. In

  18. Osteogenic Responses in Fibroblasts Activated by Elastin Degradation Products and Transforming Growth Factor-β1

    PubMed Central

    Simionescu, Agneta; Simionescu, Dan T.; Vyavahare, Narendra R.

    2007-01-01

    Our objective was to establish the role of fibroblasts in medial vascular calcification, a pathological process known to be associated with elastin degradation and remodeling. Rat dermal fibroblasts were treated in vitro with elastin degradation products and transforming growth factor (TGF)-β1, factors usually present in deteriorated matrix environments. Cellular changes were monitored at the gene and protein level by reverse transcriptase-polymerase chain reaction, enzyme-linked immunosorbent assay, immunofluorescence, and von Kossa staining for calcium deposits. By 21 days, multicellular calcified nodules were formed in the presence of elastin degradation products and TGF-β1 separately and to a significantly greater extent when used together. Before mineralization, cells expressed α-smooth muscle actin and large amounts of collagen type I and matrix metalloproteinase-2, characteristic features of myofibroblasts, key elements in tissue remodeling and repair. Stimulated cells expressed increased levels of core-binding factor α1, osteocalcin, alkaline phosphatase, and osteoprotegerin, representative bone-regulating proteins. For most proteins analyzed, TGF-β1 synergistically amplified responses of fibroblasts to elastin degradation products. In conclusion, elastin degradation products and TGF-β1 promote myofibroblastic and osteogenic differentiation in fibroblasts. These results support the idea that elastin-related calcification involves dynamic remodeling events and suggest the possibility of a defective tissue repair process. PMID:17591959

  19. P21 Activated Kinase-1 Mediates Transforming Growth Factor β1-Induced Prostate Cancer Cell Epithelial to Mesenchymal Transition

    PubMed Central

    Al-Azayzih, Ahmad; Gao, Fei; Somanath, Payaningal R.

    2015-01-01

    Transforming growth factor beta (TGFβ) is believed to play a dual role in prostate cancer. Molecular mechanism by which TGFβ1 suppresses early prostate tumor growth and induces epithelial-to-mesenchymal transition (EMT) in advanced stages is not known. We determined if P21-activated kinase1 (Pak1), which mediates cytoskeletal remodeling is necessary for the TGFβ1 induced prostate cancer EMT. Effects of TGFβ1 on control prostate cancer PC3 and DU145 cells and those with IPA 3 and siRNA mediated Pak1 inhibition were tested for prostate tumor xenograft in vivo and EMT in vitro. TGFβ1 inhibited PC3 tumor xenograft growth via activation of P38-MAPK and caspase-3, 9. Long-term stimulation with TGFβ1 induced PC3 and DU145 cell scattering and increased expression of EMT markers such as Snail and N-cadherin through tumor necrosis factor receptor-associated factor-6 (TRAF6)-mediated activation of Rac1/Pak1 pathway. Selective inhibition of Pak1 using IPA 3 or knockdown using siRNA both significantly inhibited TGFβ1-induced prostate cancer cell EMT and expression of mesenchymal markers. Our study demonstrated that TGFβ1 induces apoptosis and EMT in prostate cancer cells via activation of P38-MAPK and Rac1/Pak1 respectively. Our results reveal the potential therapeutic benefits of targeting TGFβ1-Pak1 pathway for advanced-stage prostate cancer. PMID:25746720

  20. Synergistic and multidimensional regulation of plasminogen activator inhibitor type 1 expression by transforming growth factor type β and epidermal growth factor

    SciTech Connect

    Song, Xiaoling; Thalacker, F.W.; Nilsen-Hamilton, Marit

    2012-04-06

    The major physiological inhibitor of plasminogen activator, type I plasminogen activator inhibitor (PAI-1), controls blood clotting and tissue remodeling events that involve cell migration. Transforming growth factor type β (TGFβ) and epidermal growth factor (EGF) interact synergistically to increase PAI-1 mRNA and protein levels in human HepG2 and mink Mv1Lu cells. Other growth factors that activate tyrosine kinase receptors can substitute for EGF. EGF and TGFβ regulate PAI-1 by synergistically activating transcription, which is further amplified by a decrease in the rate of mRNA degradation, the latter being regulated only by EGF. The combined effect of transcriptional activation and mRNA stabilization results in a rapid 2-order of magnitude increase in the level of PAI-1. TGFβ also increases the sensitivity of the cells to EGF, thereby recruiting the cooperation of EGF at lower than normally effective concentrations. The contribution of EGF to the regulation of PAI-1 involves the MAPK pathway, and the synergistic interface with the TGFβ pathway is downstream of MEK1/2 and involves phosphorylation of neither ERK1/2 nor Smad2/3. Synergism requires the presence of both Smad and AP-1 recognition sites in the promoter. This work demonstrates the existence of a multidimensional cellular mechanism by which EGF and TGFβ are able to promote large and rapid changes in PAI-1 expression.

  1. Grain nucleation and growth during phase transformations.

    PubMed

    Offerman, S E; van Dijk, N H; Sietsma, J; Grigull, S; Lauridsen, E M; Margulies, L; Poulsen, H F; Rekveldt, M Th; van der Zwaag, S

    2002-11-01

    The mechanical properties of polycrystalline materials are largely determined by the kinetics of the phase transformations during the production process. Progress in x-ray diffraction instrumentation at synchrotron sources has created an opportunity to study the transformation kinetics at the level of individual grains. Our measurements show that the activation energy for grain nucleation is at least two orders of magnitude smaller than that predicted by thermodynamic models. The observed growth curves of the newly formed grains confirm the parabolic growth model but also show three fundamentally different types of growth. Insight into the grain nucleation and growth mechanisms during phase transformations contributes to the development of materials with optimal mechanical properties. PMID:12411699

  2. Augmentation of natural killer cell activity in mice by oral administration of transforming growth factor-beta.

    PubMed Central

    Ishizaka, S; Kimoto, M; Kanda, S; Saito, S

    1998-01-01

    The latent form of transforming growth factor-beta (TGF-beta) in human milk and platelets was converted to the active form when conscious, pylorus-ligated mice were given human milk and platelets by intragastric intubation. Oral administration of TGF-beta exerted enhancing effects on the natural killer (NK)-cell activities in spleen and liver. Augmentation of NK-cell activities in spleen was observed for 7 days after oral administration of TGF-beta. TGF-beta at concentrations of 5 and 20 ng produced the greatest augmentation of NK-cell activities in spleen. However, NK-cell activities in spleen were unaffected when TGF-beta was given intravenously. Interleukin (IL)-12 production in spleen was enhanced by oral administration of TGF-beta, but not by intravenous administration of TGF-beta. These findings suggest that large amounts of TGF-beta in human milk are involved in early antiviral protection through the augmentation of NK-cell activities. PMID:9824511

  3. Characterization of a novel transcriptionally active domain in the transforming growth factor beta-regulated Smad3 protein.

    PubMed

    Prokova, Vassiliki; Mavridou, Sofia; Papakosta, Paraskevi; Kardassis, Dimitris

    2005-01-01

    Transforming growth factor beta (TGFbeta) regulates transcriptional responses via activation of cytoplasmic effector proteins termed Smads. Following their phosphorylation by the type I TGFbeta receptor, Smads form oligomers and translocate to the nucleus where they activate the transcription of TGFbeta target genes in cooperation with nuclear cofactors and coactivators. In the present study, we have undertaken a deletion analysis of human Smad3 protein in order to characterize domains that are essential for transcriptional activation in mammalian cells. With this analysis, we showed that Smad3 contains two domains with transcriptional activation function: the MH2 domain and a second middle domain that includes the linker region and the first two beta strands of the MH2 domain. Using a protein-protein interaction assay based on biotinylation in vivo, we were able to show that a Smad3 protein bearing an internal deletion in the middle transactivation domain is characterized by normal oligomerization and receptor activation properties. However, this mutant has reduced transactivation capacity on synthetic or natural promoters and is unable to interact physically and functionally with the histone acetyltransferase p/CAF. The loss of interaction with p/CAF or other coactivators could account, at least in part, for the reduced transactivation capacity of this Smad3 mutant. Our data support an essential role of the previously uncharacterized middle region of Smad3 for nuclear functions, such as transcriptional activation and interaction with coactivators. PMID:15994459

  4. A novel inhibitor of cyclin-Cdk activity detected in transforming growth factor beta-arrested epithelial cells.

    PubMed Central

    Slingerland, J M; Hengst, L; Pan, C H; Alexander, D; Stampfer, M R; Reed, S I

    1994-01-01

    Transforming growth factor beta (TGF-beta) is a potent inhibitor of epithelial cell growth. Cyclins E and A in association with Cdk2 have been shown to play a role in the G1-to-S phase transition in mammalian cells. We have studied the effects of TGF-beta-mediated growth arrest on G1/S cyclins E and A. Inhibition of cyclin A-associated kinase by TGF-beta is primarily due to a decrease in cyclin A mRNA and protein. By contrast, while TGF-beta inhibits accumulation of cyclin E mRNA, the reduction in cyclin E protein is minimal. Instead, we find that the activation of cyclin E-associated kinase that normally accompanies the G1-to-S phase transition is inhibited. A novel inhibitor of cyclin-Cdk complexes was detected in TGF-beta-treated cell lysates. Inhibition is mediated by a heat-stable protein that targets both Cdk2 and Cdc2 kinases. In G0-arrested cells, a similar inhibitor of Cdk2 kinase was detected. These data suggest the existence of an inhibitor of cyclin-dependent kinases induced under different conditions to mediate antiproliferative responses. Images PMID:8196612

  5. Transforming Growth Factor-Beta and Urokinase-Type Plasminogen Activator: Dangerous Partners in Tumorigenesis—Implications in Skin Cancer

    PubMed Central

    Santibanez, Juan F.

    2013-01-01

    Transforming growth factor-beta (TGF-β) is a pleiotropic factor, with several different roles in health and disease. TGF-β has been postulated as a dual factor in tumor progression, since it represses epithelial tumor development in early stages, whereas it stimulates tumor progression in advanced stages. During tumorigenesis, cancer cells acquire the capacity to migrate and invade surrounding tissues and to metastasize different organs. The urokinase-type plasminogen activator (uPA) system, comprising uPA, the uPA cell surface receptor, and plasminogen-plasmin, is involved in the proteolytic degradation of the extracellular matrix and regulates key cellular events by activating intracellular signal pathways, which together allow cancer cells to survive, thus, enhancing cell malignance during tumor progression. Due to their importance, uPA and its receptor are tightly transcriptionally regulated in normal development, but are deregulated in cancer, when their activity and expression are related to further development of cancer. TGF-β regulates uPA expression in cancer cells, while uPA, by plasminogen activation, may activate the secreted latent TGF-β, thus, producing a pernicious cycle which contributes to the enhancement of tumor progression. Here we review the specific roles and the interplay between TGF-β and uPA system in cancer cells and their implication in skin cancer. PMID:23984088

  6. High glucose increases Cdk5 activity in podocytes via transforming growth factor-β1 signaling pathway

    SciTech Connect

    Zhang, Yue; Li, Hongbo; Hao, Jun; Zhou, Yi; Liu, Wei

    2014-08-15

    Podocytes are highly specialized and terminally differentiated glomerular cells that play a vital role in the development and progression of diabetic nephropathy (DN). Cyclin-dependent kinase 5 (Cdk5), who is an atypical but essential member of the Cdk family of proline-directed serine/threonine kinases, has been shown as a key regulator of podocyte differentiation, proliferation and morphology. Our previous studies demonstrated that the expression of Cdk5 was significantly increased in podocytes of diabetic rats, and was closely related with podocyte injury of DN. However, the mechanisms of how expression and activity of Cdk5 are regulated under the high glucose environment have not yet been fully elucidated. In this study, we showed that high glucose up-regulated the expression of Cdk5 and its co-activator p35 with a concomitant increase in Cdk5 kinase activity in conditionally immortalized mouse podocytes in vitro. When exposed to 30 mM glucose, transforming growth factor-β1 (TGF-β1) was activated. Most importantly, we found that SB431542, the Tgfbr1 inhibitor, significantly decreased the expression of Cdk5 and p35 and Cdk5 kinase activity in high glucose-treated podocytes. Moreover, high glucose increased the expression of early growth response-1 (Egr-1) via TGF-β1-ERK1/2 pathway in podocytes and inhibition of Egr-1 by siRNA decreased p35 expression and Cdk5 kinase activity. Furthermore, inhibition of Cdk5 kinase activity effectively alleviated podocyte apoptosis induced by high glucose or TGF-β1. Thus, the TGF-β1-ERK1/2-Egr-1 signaling pathway may regulate the p35 expression and Cdk5 kinase activity in high glucose-treated podocytes, which contributes to podocyte injury of DN. - Highlights: • HG up-regulated the expression of Cdk5 and p35, and Cdk5 activity in podocytes. • HG activated TGF-β1 pathway and SB431542 inhibited Cdk5 expression and activity. • HG increased the expression of Egr-1 via TGF-β1-ERK1/2 pathway. • Inhibition of Egr-1

  7. Transforming growth factor-beta activation in irradiated murine mammary gland.

    PubMed Central

    Barcellos-Hoff, M H; Derynck, R; Tsang, M L; Weatherbee, J A

    1994-01-01

    The biological activity of TGF-beta, an important modulator of cell proliferation and extracellular matrix formation, is governed by dissociation of mature TGF-beta from an inactive, latent TGF-beta complex in a process that is critical to its role in vivo. So far, it has not been possible to monitor activation in vivo since conventional immunohistochemical detection does not accurately discriminate latent versus active TGF-beta, nor have events associated with activation been defined well enough to serve as in situ markers of this process. We describe here a modified immunodetection method using differential antibody staining that allows the specific detection of active versus latent TGF-beta. Under these conditions, we report that an antibody raised to latency-associated peptide detects latent TGF-beta, and we demonstrate that LC(1-30) antibodies specifically recognize active TGF-beta 1 in tumor xenografts overproducing active TGF-beta 1, without cross-reactivity in tumors expressing similar levels of latent TGF-beta 1. We previously reported that TGF-beta immunoreactivity increases in murine mammary gland after whole-body 60Co-gamma radiation exposure. Using differential antibody staining we now show that radiation exposure specifically generates active TGF-beta 1. While latent TGF-beta 1 was widely distributed in unirradiated tissue, active TGF-beta 1 distribution was restricted. Active TGF-beta 1 increased significantly within 1 h of irradiation concomitant with decreased latent TGF-beta immunoreactivity. This rapid shift in immunoreactivity provides the first evidence for activation of TGF-beta in situ. This reciprocal pattern of expression persisted for 3 d and was accompanied by decreased recovery of latent TGF-beta 1 from irradiated tissue. Radiation-induced activation of TGF-beta may have profound implications for understanding tissue effects caused by radiation therapy. Images PMID:8113421

  8. Alteration of N-glycoproteins/N-glycosites in human hepatic stellate cells activated with transforming growth factor-β1.

    PubMed

    Qin, Y; Wang, Q; Zhong, Y; Zhao, F; Wu, F; Wang, Y; Ma, T; Liu, C; Bian, H; Li, Z

    2016-01-01

    Proteins N-glycosylation is significantly increased in the activated human hepatic stellate cells (HSCs) stimulated by transforming growth factor-β1 (TGF-β1) compared to the quiescent HSCs according to our previous study. However, little is known about the alteration of N-glycoprotein profiles in the activated HSCs. Profiles of N-glycopeptides / N-glycoproteins / N-glycosites in LX-2 cells, with and without activation by TGF-β1, were identified and compared using hydrazide chemistry enrichment coupled with liquid chromatography - mass spectrometry analysis. Western blot and immunohistochemistry were further used for validation. A total of 103 non-redundant N-glycopeptides, with 107 glycosylation sites from 86 N-glycoproteins, were identified in activated and quiescent LX-2 cells respectively. Among these, 23 proteins were known N-glycoproteins, and 58 were newly identified N-glycoproteins. In addition, 43 proteins (e.g., pigment epithelium-derived factor and clathrin heavy chain 1) were solely identified or up-regulated in the activated LX-2 cells, which participated in focal adhesion and glycosaminoglycan degradation pathways and were involved in interaction clusters of cytoskeletal proteins (e.g., myosin light chains and keratins). The increased expression of glucosamine (N-acetyl)-6-sulfatase and phospholipase C beta 2 and the decreased expression of zinc finger and BTB domain-containing protein 1 were validated in the activated compared to the quiescent LX-2 cells. In conclusion, increased expression of N-glycoproteins and N-glycosites play important roles in cellular contractility, signal transduction, and responses to stimuli in the activated HSCs, which might provide useful information for discovering novel molecular mechanism of HSC activation and therapeutic targets in liver fibrosis. PMID:27064874

  9. Influenza Promotes Collagen Deposition via αvβ6 Integrin-mediated Transforming Growth Factor β Activation*

    PubMed Central

    Jolly, Lisa; Stavrou, Anastasios; Vanderstoken, Gilles; Meliopoulos, Victoria A.; Habgood, Anthony; Tatler, Amanda L.; Porte, Joanne; Knox, Alan; Weinreb, Paul; Violette, Shelia; Hussell, Tracy; Kolb, Martin; Stampfli, Martin R.; Schultz-Cherry, Stacey; Jenkins, Gisli

    2014-01-01

    Influenza infection exacerbates chronic pulmonary diseases, including idiopathic pulmonary fibrosis. A central pathway in the pathogenesis of idiopathic pulmonary fibrosis is epithelial injury leading to activation of transforming growth factor β (TGFβ). The mechanism and functional consequences of influenza-induced activation of epithelial TGFβ are unclear. Influenza stimulates toll-like receptor 3 (TLR3), which can increase RhoA activity, a key event prior to activation of TGFβ by the αvβ6 integrin. We hypothesized that influenza would stimulate TLR3 leading to activation of latent TGFβ via αvβ6 integrin in epithelial cells. Using H1152 (IC50 6.1 μm) to inhibit Rho kinase and 6.3G9 to inhibit αvβ6 integrins, we demonstrate their involvement in influenza (A/PR/8/34 H1N1) and poly(I:C)-induced TGFβ activation. We confirm the involvement of TLR3 in this process using chloroquine (IC50 11.9 μm) and a dominant negative TLR3 construct (pZERO-hTLR3). Examination of lungs from influenza-infected mice revealed augmented levels of collagen deposition, phosphorylated Smad2/3, αvβ6 integrin, and apoptotic cells. Finally, we demonstrate that αvβ6 integrin-mediated TGFβ activity following influenza infection promotes epithelial cell death in vitro and enhanced collagen deposition in vivo and that this response is diminished in Smad3 knock-out mice. These data show that H1N1 and poly(I:C) can induce αvβ6 integrin-dependent TGFβ activity in epithelial cells via stimulation of TLR3 and suggest a novel mechanism by which influenza infection may promote collagen deposition in fibrotic lung disease. PMID:25339175

  10. Nucleation and growth transformation kinetics

    NASA Astrophysics Data System (ADS)

    Erukhimovitch, V.; Baram, J.

    1995-03-01

    As a result of the reassessment of the Kolmogorov-Johnson-Mehl-Avrami (KJMA) theory for the kinetics of nucleation and growth transformations, an integral-equation formulation has been developed instead of the well-known and widely used Avrami equation. The presented formulation considers interfacial and diffusional growths, in one, two, and three dimensions, with both time-dependent and time-invariant nucleation and growth rates. The integral-equation model corrects reported inadequacies of the KJMA theory when applied in numerous experiments and various solid-state transformations. It is shown that in the example cases examined in this paper, crystallization from the amorphous state in melt-spun ribbons, isothermal aging of CuAlZn, pearlitic transition in an eutectoid steel, and crystallization in a PEKK polymer, the thermodynamic and kinetic interpretation and parameters extracted from best fits of the Avrami equations to the experimental data are erroneous. The KJMA formulation is a simplification of the real physical conditions. The main limitation of the new model is that almost all the integral equations representing the kinetics of solid-state transformations have no analytical solutions.

  11. Granzyme B Cleaves Decorin, Biglycan and Soluble Betaglycan, Releasing Active Transforming Growth Factor-β1

    PubMed Central

    Boivin, Wendy A.; Shackleford, Marlo; Vanden Hoek, Amanda; Zhao, Hongyan; Hackett, Tillie L.; Knight, Darryl A.; Granville, David J.

    2012-01-01

    Objective Granzyme B (GrB) is a pro-apoptotic serine protease that contributes to immune-mediated target cell apoptosis. However, during inflammation, GrB accumulates in the extracellular space, retains its activity, and is capable of cleaving extracellular matrix (ECM) proteins. Recent studies have implicated a pathogenic extracellular role for GrB in cardiovascular disease, yet the pathophysiological consequences of extracellular GrB activity remain largely unknown. The objective of this study was to identify proteoglycan (PG) substrates of GrB and examine the ability of GrB to release PG-sequestered TGF-β1 into the extracellular milieu. Methods/Results Three extracellular GrB PG substrates were identified; decorin, biglycan and betaglycan. As all of these PGs sequester active TGF-β1, cytokine release assays were conducted to establish if GrB-mediated PG cleavage induced TGF-β1 release. Our data confirmed that GrB liberated TGF-β1 from all three substrates as well as from endogenous ECM and this process was inhibited by the GrB inhibitor 3,4-dichloroisocoumarin. The released TGF-β1 retained its activity as indicated by the induction of SMAD-3 phosphorylation in human coronary artery smooth muscle cells. Conclusion In addition to contributing to ECM degradation and the loss of tissue structural integrity in vivo, increased extracellular GrB activity is also capable of inducing the release of active TGF-β1 from PGs. PMID:22479366

  12. p130Cas Is Required for Mammary Tumor Growth and Transforming Growth Factor-β-mediated Metastasis through Regulation of Smad2/3 Activity*

    PubMed Central

    Wendt, Michael K.; Smith, Jason A.; Schiemann, William P.

    2009-01-01

    During breast cancer progression, transforming growth factor-β (TGF-β) switches from a tumor suppressor to a pro-metastatic molecule. Several recent studies suggest that this conversion in TGF-β function depends upon fundamental changes in the TGF-β signaling system. We show here that these changes in TGF-β signaling are concomitant with aberrant expression of the focal adhesion protein, p130Cas. Indeed, elevating expression of either the full-length (FL) or just the carboxyl terminus (CT) of p130Cas in mammary epithelial cells (MECs) diminished the ability of TGF-β1 to activate Smad2/3, but increased its coupling to p38 MAPK. This shift in TGF-β signaling evoked (i) resistance to TGF-β-induced growth arrest, and (ii) acinar filling upon three-dimensional organotypic cultures of p130Cas-FL or -CT expressing MECs. Furthermore, rendering metastatic MECs deficient in p130Cas enhanced TGF-β-stimulated Smad2/3 activity, which restored TGF-β-induced growth inhibition both in vitro and in mammary tumors produced in mice. Additionally, whereas elevating TβR-II expression in metastatic MECs had no affect on their phosphorylation of Smad2/3, this event markedly enhanced their activation of p38 MAPK, leading to increased MEC invasion and metastasis. Importantly, depleting p130Cas expression in TβR-II-expressing metastatic MECs significantly increased their activation of Smad2/3, which (i) reestablished the physiologic balance between canonical and noncanonical TGF-β signaling, and (ii) reversed cellular invasion and early mammary tumor cell dissemination stimulated by TGF-β. Collectively, our findings identify p130Cas as a molecular rheostat that regulates the delicate balance between canonical and noncanonical TGF-β signaling, a balance that is critical to maintaining the tumor suppressor function of TGF-β during breast cancer progression. PMID:19822523

  13. Latent transforming growth factor beta1 activation in situ: quantitative and functional evidence after low-dose gamma-irradiation

    NASA Technical Reports Server (NTRS)

    Ehrhart, E. J.; Segarini, P.; Tsang, M. L.; Carroll, A. G.; Barcellos-Hoff, M. H.; Chatterjee, A. (Principal Investigator)

    1997-01-01

    The biological activity of transforming growth factor beta1 (TGF-beta) is controlled by its secretion as a latent complex in which it is noncovalently associated with latency-associated peptide (LAP). Activation is the extracellular process in which TGF-beta is released from LAP, and is considered to be a primary regulatory control. We recently reported rapid and persistent changes in TGF-beta immunoreactivity in conjunction with extracellular matrix remodeling in gamma-irradiated mouse mammary gland. Our hypothesis is that these specific changes in immunoreactivity are indicative of latent TGF-beta activation. In the present study, we determined the radiation dose response and tested whether a functional relationship exists between radiation-induced TGF-beta and collagen type III remodeling. After radiation exposures as low as 0.1 Gy, we detected increased TGF-beta immunoreactivity in the mammary epithelium concomitant with decreased LAP immunostaining, which are events consistent with activation. Quantitative image analysis demonstrated a significant (P=0.0005) response at 0.1 Gy without an apparent threshold and a linear dose response to 5 Gy. However, in the adipose stroma, loss of LAP demonstrated a qualitative threshold at 0.5 Gy. Loss of LAP paralleled induction of collagen III immunoreactivity in this tissue compartment. We tested whether TGF-beta mediates collagen III expression by treating animals with TGF-beta panspecific monoclonal antibody, 1D11.16, administered i.p. shortly before irradiation. Radiation-induced collagen III staining in the adipose stroma was blocked in an antibody dose-dependent manner, which persisted through 7 days postirradiation. RNase protection assay revealed that radiation-induced elevation of total gland collagen III mRNA was also blocked by neutralizing antibody treatment. These data provide functional confirmation of the hypothesis that radiation exposure leads to latent TGF-beta activation, support our interpretation of the

  14. Transforming Growth Factor β-1 Stimulates Profibrotic Epithelial Signaling to Activate Pericyte-Myofibroblast Transition in Obstructive Kidney Fibrosis

    PubMed Central

    Wu, Ching-Fang; Chiang, Wen-Chih; Lai, Chun-Fu; Chang, Fan-Chi; Chen, Yi-Ting; Chou, Yu-Hsiang; Wu, Ting-Hui; Linn, Geoffrey R.; Ling, Hong; Wu, Kwan-Dun; Tsai, Tun-Jun; Chen, Yung-Ming; Duffield, Jeremy S.; Lin, Shuei-Liong

    2014-01-01

    Pericytes have been identified as the major source of precursors of scar-producing myofibroblasts during kidney fibrosis. The underlying mechanisms triggering pericyte-myofibroblast transition are poorly understood. Transforming growth factor β-1 (TGF-β1) is well recognized as a pluripotent cytokine that drives organ fibrosis. We investigated the role of TGF-β1 in inducing profibrotic signaling from epithelial cells to activate pericyte-myofibroblast transition. Increased expression of TGF-β1 was detected predominantly in injured epithelium after unilateral ureteral obstruction, whereas downstream signaling from the TGF-β1 receptor increased in both injured epithelium and pericytes. In mice with ureteral obstruction that were treated with the pan anti–TGF-β antibody (1D11) or TGF-β receptor type I inhibitor (SB431542), kidney pericyte-myofibroblast transition was blunted. The consequence was marked attenuation of fibrosis. In addition, epithelial cell cycle G2/M arrest and production of profibrotic cytokines were both attenuated. Although TGF-β1 alone did not trigger pericyte proliferation in vitro, it robustly induced α smooth muscle actin (α-SMA). In cultured kidney epithelial cells, TGF-β1 stimulated G2/M arrest and production of profibrotic cytokines that had the capacity to stimulate proliferation and transition of pericytes to myofibroblasts. In conclusion, this study identified a novel link between injured epithelium and pericyte-myofibroblast transition through TGF-β1 during kidney fibrosis. PMID:23142380

  15. 5-Azacytidine treatment of HA-A melanoma cells induces Sp1 activity and concomitant transforming growth factor alpha expression.

    PubMed Central

    Shin, T H; Paterson, A J; Grant, J H; Meluch, A A; Kudlow, J E

    1992-01-01

    Evidence indicates DNA methylation as a part of the regulatory machinery controlling mammalian gene expression. The human melanoma cell line HA-A expresses low levels of transforming growth factor alpha (TGF-alpha). TGF-alpha mRNA accumulated, however, in response to DNA demethylation induced by a nucleoside analog, 5-azacytidine (5-azaC). The importance of DNA methylation in the TGF-alpha promoter region was examined by a transient transfection assay with luciferase reporter plasmids containing a portion of the TGF-alpha promoter. 5-azaC treatment of HA-A cells before the transfection caused a significant increase in the luciferase activity. Since input plasmids were confirmed to remain unmethylated, DNA demethylation of the TGF-alpha promoter itself does not account for the observed increase in TGF-alpha mRNA. Using an electrophoretic mobility shift assay, enhanced formation of protein-TGF-alpha promoter complex was detected in response to 5-azaC treatment. This 5-azaC-induced complex was shown to contain the transcription factor Sp1 by the following criteria: the protein-DNA complex formed on the TGF-alpha promoter contained immunoreactive Sp1; the mobility of the complex in an electrophoretic mobility shift assay was similar to that formed by recombinant Sp1; and DNase I footprinting analysis demonstrated that the 5-azaC-induced complex produced a footprint on the TGF-alpha promoter identical to that of authentic Sp1. These observations suggest that 5-azaC induces TGF-alpha expression by augmenting the Sp1 activity. However, neither the Sp1 mRNA nor its protein was induced by 5-azaC. These results suggest that in HA-A cells, TGF-alpha expression is down-modulated by DNA methylation. In addition, this process may involve the specific regulation of Sp1 activity without altering the amount of the transcription factor. Images PMID:1380648

  16. Epithelial to mesenchymal transition in arsenic-transformed cells promotes angiogenesis through activating β-catenin–vascular endothelial growth factor pathway

    SciTech Connect

    Wang, Zhishan; Humphries, Brock; Xiao, Hua; Jiang, Yiguo; Yang, Chengfeng

    2013-08-15

    Arsenic exposure represents a major health concern increasing cancer risks, yet the mechanism of arsenic carcinogenesis has not been elucidated. We and others recently reported that cell malignant transformation by arsenic is accompanied by epithelial to mesenchymal transition (EMT). However, the role of EMT in arsenic carcinogenesis is not well understood. Although previous studies showed that short term exposure of endothelial cells to arsenic stimulated angiogenesis, it remains to be determined whether cells that were malignantly transformed by long term arsenic exposure have a pro-angiogenic effect. The objective of this study was to investigate the effect of arsenic-transformed human bronchial epithelial cells that underwent EMT on angiogenesis and the underlying mechanism. It was found that the conditioned medium from arsenic-transformed cells strongly stimulated tube formation by human umbilical vein endothelial cells (HUVECs). Moreover, enhanced angiogenesis was detected in mouse xenograft tumor tissues resulting from inoculation of arsenic-transformed cells. Mechanistic studies revealed that β-catenin was activated in arsenic-transformed cells up-regulating its target gene expression including angiogenic-stimulating vascular endothelial growth factor (VEGF). Stably expressing microRNA-200b in arsenic-transformed cells that reversed EMT inhibited β-catenin activation, decreased VEGF expression and reduced tube formation by HUVECs. SiRNA knockdown β-catenin decreased VEGF expression. Adding a VEGF neutralizing antibody into the conditioned medium from arsenic-transformed cells impaired tube formation by HUVECs. Reverse transcriptase-PCR analysis revealed that the mRNA levels of canonical Wnt ligands were not increased in arsenic-transformed cells. These findings suggest that EMT in arsenic-transformed cells promotes angiogenesis through activating β-catenin–VEGF pathway. - Highlights: • Arsenic-transformed cells that underwent EMT displayed a pro

  17. Transforming growth factor beta 1 and gamma interferon provide opposing signals to lipopolysaccharide-activated mouse macrophages.

    PubMed Central

    Hausmann, E H; Hao, S Y; Pace, J L; Parmely, M J

    1994-01-01

    Bacterial lipopolysaccharides (LPS) are potent inducers of macrophage activation, leading to the production of a number of proinflammatory mediators. Although several cytokines that prime macrophages for enhanced LPS-triggered responses have been identified, far less is known regarding the role that cytokines play in down-regulating macrophage responses to LPS. This study was designed to determine the effects of recombinant transforming growth factor beta 1 (rTGF-beta 1) on macrophage activation by LPS. Pretreatment of either mouse peritoneal macrophages or cells of the RAW 264.7 macrophage-like cell line with rTGF-beta 1 inhibited their ability to produce both tumor necrosis factor alpha (TNF-alpha) and nitric oxide (NO) in response to LPS. These inhibitory effects were reversed by increasing the concentration of LPS or by priming cells with optimal concentrations of recombinant gamma interferon (rIFN-gamma). Pretreatment of cells with rTGF-beta 1 had only a modest inhibitory effect on the expression of TNF-alpha mRNA. By contrast, the expression of mRNA for the inducible form of nitric oxide synthase (iNOS), which is responsible for NO production in activated macrophages, was significantly inhibited by rTGF-beta 1 pretreatment. Thus, rTGF-beta 1-dependent suppression of macrophage TNF-alpha biosynthesis was manifest at a posttranscriptional level, whereas the inhibition of NO production correlated with a direct effect on iNOS gene expression. Importantly, both of these suppressive effects of rTGF-beta 1 were reversed by exposing the cells to priming concentrations of rIFN-gamma. As with NO production, immunocytochemical analysis of iNOS expression in LPS-stimulated macrophages revealed that rIFN-gamma and rTGF-beta 1 had antagonistic effects, with the former increasing, and the latter reducing, the number of iNOS-expressing cells induced by LPS. These data suggest that a balance between the priming effects of IFN-gamma and the inhibitory effects of TGF-beta 1 can

  18. Dissecting the role of transforming growth factor-β1 in topmouth culter immunobiological activity: a fundamental functional analysis

    PubMed Central

    Qi, Pengzhi; Xie, Congxin; Guo, Baoying; Wu, Changwen

    2016-01-01

    Transforming growth factor-β1 (TGF-β1) has been proven to function primarily in mammalian immunobiological activity, but information regarding the immune role of TGF-β1 in teleosts is limited. In the present study, we describe the cDNA cloning and characterization of the TGF-β1 molecule in the topmouth culter. TGF-β1 is highly expressed in immune-related tissues of the culter, including the thymus, head kidney, and spleen. The recombinant culter TGF-β1 (cTGF-β1) was successfully expressed and purified in vitro, and the effects of cTGF-β1 on the mRNA expression of pro-inflammatory cytokines, such as TNF-α and IL-1β, in the absence or presence of LPS was determined in culter peripheral blood leukocytes. cTGF-β1 was found to have bipolar properties in inflammatory reactions. Additionally, to assess the immune role of teleost TGF-β1 in vivo, the expression of TGF-β1 in the culter thymus and spleen tissues induced by poly I:C were also examined. The expression of TGF-β1 was obviously up-regulated, as shown in the cell lines. However, the peak time of cTGF-β1 expression in the cell lines occurred significantly earlier than in the organic tissues under the same inducer, suggesting that the response of the teleost TGF-β1 molecule to exogenous infection depends on a more complicated signalling pathway in vivo than in vitro. PMID:27251472

  19. Dissecting the role of transforming growth factor-β1 in topmouth culter immunobiological activity: a fundamental functional analysis.

    PubMed

    Qi, Pengzhi; Xie, Congxin; Guo, Baoying; Wu, Changwen

    2016-01-01

    Transforming growth factor-β1 (TGF-β1) has been proven to function primarily in mammalian immunobiological activity, but information regarding the immune role of TGF-β1 in teleosts is limited. In the present study, we describe the cDNA cloning and characterization of the TGF-β1 molecule in the topmouth culter. TGF-β1 is highly expressed in immune-related tissues of the culter, including the thymus, head kidney, and spleen. The recombinant culter TGF-β1 (cTGF-β1) was successfully expressed and purified in vitro, and the effects of cTGF-β1 on the mRNA expression of pro-inflammatory cytokines, such as TNF-α and IL-1β, in the absence or presence of LPS was determined in culter peripheral blood leukocytes. cTGF-β1 was found to have bipolar properties in inflammatory reactions. Additionally, to assess the immune role of teleost TGF-β1 in vivo, the expression of TGF-β1 in the culter thymus and spleen tissues induced by poly I:C were also examined. The expression of TGF-β1 was obviously up-regulated, as shown in the cell lines. However, the peak time of cTGF-β1 expression in the cell lines occurred significantly earlier than in the organic tissues under the same inducer, suggesting that the response of the teleost TGF-β1 molecule to exogenous infection depends on a more complicated signalling pathway in vivo than in vitro. PMID:27251472

  20. Kaiso depletion attenuates transforming growth factor-β signaling and metastatic activity of triple-negative breast cancer cells.

    PubMed

    Bassey-Archibong, B I; Kwiecien, J M; Milosavljevic, S B; Hallett, R M; Rayner, L G A; Erb, M J; Crawford-Brown, C J; Stephenson, K B; Bédard, P-A; Hassell, J A; Daniel, J M

    2016-01-01

    Triple-negative breast cancers (TNBCs) represent a subset of breast tumors that are highly aggressive and metastatic, and are responsible for a disproportionate number of breast cancer-related deaths. Several studies have postulated a role for the epithelial-to-mesenchymal transition (EMT) program in the increased aggressiveness and metastatic propensity of TNBCs. Although EMT is essential for early vertebrate development and wound healing, it is frequently co-opted by cancer cells during tumorigenesis. One prominent signaling pathway involved in EMT is the transforming growth factor-β (TGFβ) pathway. In this study, we report that the novel POZ-ZF transcription factor Kaiso is highly expressed in TNBCs and correlates with a shorter metastasis-free survival. Notably, Kaiso expression is induced by the TGFβ pathway and silencing Kaiso expression in the highly invasive breast cancer cell lines, MDA-MB-231 (hereafter MDA-231) and Hs578T, attenuated the expression of several EMT-associated proteins (Vimentin, Slug and ZEB1), abrogated TGFβ signaling and TGFβ-dependent EMT. Moreover, Kaiso depletion attenuated the metastasis of TNBC cells (MDA-231 and Hs578T) in a mouse model. Although high Kaiso and high TGFβR1 expression is associated with poor overall survival in breast cancer patients, overexpression of a kinase-active TGFβR1 in the Kaiso-depleted cells was insufficient to restore the metastatic potential of these cells, suggesting that Kaiso is a key downstream component of TGFβ-mediated pro-metastatic responses. Collectively, these findings suggest a critical role for Kaiso in TGFβ signaling and the metastasis of TNBCs. PMID:26999717

  1. Kaiso depletion attenuates transforming growth factor-β signaling and metastatic activity of triple-negative breast cancer cells

    PubMed Central

    Bassey-Archibong, B I; Kwiecien, J M; Milosavljevic, S B; Hallett, R M; Rayner, L G A; Erb, M J; Crawford-Brown, C J; Stephenson, K B; Bédard, P-A; Hassell, J A; Daniel, J M

    2016-01-01

    Triple-negative breast cancers (TNBCs) represent a subset of breast tumors that are highly aggressive and metastatic, and are responsible for a disproportionate number of breast cancer-related deaths. Several studies have postulated a role for the epithelial-to-mesenchymal transition (EMT) program in the increased aggressiveness and metastatic propensity of TNBCs. Although EMT is essential for early vertebrate development and wound healing, it is frequently co-opted by cancer cells during tumorigenesis. One prominent signaling pathway involved in EMT is the transforming growth factor-β (TGFβ) pathway. In this study, we report that the novel POZ-ZF transcription factor Kaiso is highly expressed in TNBCs and correlates with a shorter metastasis-free survival. Notably, Kaiso expression is induced by the TGFβ pathway and silencing Kaiso expression in the highly invasive breast cancer cell lines, MDA-MB-231 (hereafter MDA-231) and Hs578T, attenuated the expression of several EMT-associated proteins (Vimentin, Slug and ZEB1), abrogated TGFβ signaling and TGFβ-dependent EMT. Moreover, Kaiso depletion attenuated the metastasis of TNBC cells (MDA-231 and Hs578T) in a mouse model. Although high Kaiso and high TGFβR1 expression is associated with poor overall survival in breast cancer patients, overexpression of a kinase-active TGFβR1 in the Kaiso-depleted cells was insufficient to restore the metastatic potential of these cells, suggesting that Kaiso is a key downstream component of TGFβ-mediated pro-metastatic responses. Collectively, these findings suggest a critical role for Kaiso in TGFβ signaling and the metastasis of TNBCs. PMID:26999717

  2. High glucose concentration induces the overexpression of transforming growth factor-beta through the activation of a platelet-derived growth factor loop in human mesangial cells.

    PubMed Central

    Di Paolo, S.; Gesualdo, L.; Ranieri, E.; Grandaliano, G.; Schena, F. P.

    1996-01-01

    High glucose concentration has been shown to induce the overexpression of transforming growth factor (TGF)-beta 1 mRNA and protein in different cell types, including murine mesangial cells, thus possibly accounting for the expansion of mesangial extracellular matrix observed in diabetic glomerulopathy. In the present study, we evaluated platelet-derived growth factor (PDGF) B-chain and PDGF-beta receptor gene expression in human mesangial cells (HMCs) exposed to different concentrations of glucose and then sought a possible relationship between a PDGF loop and the modulation of TGF-beta 1 expression. HMC [3H]thymidine incorporation was upregulated by 30 mmol/L glucose (HG) up to 24 hours, whereas it was significantly inhibited at later time points. Neutralizing antibodies to PDGF BB abolished the biphasic response to HG, whereas anti-TGF-beta antibodies reversed only the late inhibitory effect of hyperglycemic medium. HG induced an early and persistent increase of PDGF B-chain gene expression, as evaluated by reverse transcriptase polymerase chain reaction, whereas PDGF-beta receptor mRNA increased by twofold after 6 hours, thereafter declining at levels 70% lower than in controls after 24 hours. 125I-Labeled PDGF BB binding studies in HMCs exposed to HG for 24 hours confirmed the decrease of PDGF-beta receptor expression. TGF-beta 1-specific transcripts showed 43 and 78% increases after 24 and 48 hours of incubation in HG, respectively, which was markedly diminished by anti-PDGF BB neutralizing antibodies or suramin. We conclude that HG induces an early activation of a PDGF loop that, in turn, causes an increase of TGF-beta 1 gene expression, thus modulating both HMC proliferation and mesangial matrix production. Images Figure 2 Figure 3 Figure 4 Figure 5 PMID:8952542

  3. Regulation of the herpesvirus saimiri oncogene stpC, similar to that of T-cell activation genes, in growth-transformed human T lymphocytes.

    PubMed Central

    Fickenscher, H; Biesinger, B; Knappe, A; Wittmann, S; Fleckenstein, B

    1996-01-01

    Herpesvirus saimiri strain C488, a T-cell tumor virus of New World primates, transforms human T lymphocytes to stable interleukin-2-dependent growth without need for further stimulation by antigen or mitogen. The transformed cell lines show the phenotype of activated mature T cells and retain many essential features of the primary parental cells, e.g., antigen specificity. In contrast to transformed New World monkey T cells, the human lines do not support lytic growth of the virus, even after chemical stimulation. Here we show that many viral genes remain silent during episomal persistence. However, the viral oncogene stpC is predominantly transcribed and translated to a stable cytoplasmic protein of 20 kDa that is heterogeneously expressed in individual cells. This 1.7-kb mRNA is bicistronic, encoding also Tip, a viral protein interacting with the T-cell-specific tyrosine kinase Lck. stpC/tip transcripts are heavily induced upon stimulation by mitogen or phorbol ester. Block of protein synthesis does not abolish transcription: treatment with cycloheximide greatly induces stpC/tip mRNA levels. Thus, this gene complex is regulated similarly to early T-cell activation genes. Constitutive and induced expression engage different transcription start sites. The T-cell regulation of the viral genes stpC and tip may contribute to the T-cell tropism of growth transformation by herpesvirus saimiri. PMID:8709223

  4. Transforming growth factor-beta1-induced activation of the Raf-MEK-MAPK signaling pathway in rat lung fibroblasts via a PKC-dependent mechanism.

    PubMed

    Axmann, A; Seidel, D; Reimann, T; Hempel, U; Wenzel, K W

    1998-08-19

    In fibroblasts transforming growth factor-beta1 (TGF-beta1) regulates cell proliferation and turnover of macromolecular components of the extracellular matrix. Here, intracellular signaling events in growth-inhibited embryonic rat lung fibroblasts (RFL-6) upon stimulation with TGF-beta1 were investigated. TGF-beta1 rapidly induced the activation of c-Raf-1, MEK-1, and MAPK p42 and p44. The activation of this pathway by TGF-beta1 did not depend on autocrine platelet-derived growth factor (PDGF) or basic fibroblast growth factor (bFGF). Inhibition of the binding of growth factors to their tyrosine kinase receptors did not affect MAPK activation by TGF-beta1. Ras activation by TGF-beta1 was significantly lower compared to the activation by PDGF or bFGF. The intracellular transduction of the TGF-beta1 signal was completely suppressed by depletion or inhibition of protein kinase C (PKC). It is shown that calcium-dependent isoforms of PKC are required for MAPK activation by TGF-beta1. PMID:9712718

  5. Constitutive activation of epidermal growth factor receptor promotes tumorigenesis of Cr(VI)-transformed cells through decreased reactive oxygen species and apoptosis resistance development.

    PubMed

    Kim, Donghern; Dai, Jin; Fai, Leonard Yenwong; Yao, Hua; Son, Young-Ok; Wang, Lei; Pratheeshkumar, Poyil; Kondo, Kazuya; Shi, Xianglin; Zhang, Zhuo

    2015-01-23

    Hexavalent chromium (Cr(VI)) compounds are well-established lung carcinogens. Epidermal growth factor receptor (EGFR) is a tyrosine kinase transmembrane receptor that regulates cell survival, tumor invasion, and angiogenesis. Our results show that chronic exposure of human bronchial epithelial (BEAS-2B) cells to Cr(VI) is able to cause malignant cell transformation. These transformed cells exhibit apoptosis resistance with reduced poly ADP-ribose polymerase cleavage (C-PARP) and Bax expression and enhanced expressions of Bcl-2 and Bcl-xL. These transformed cells also exhibit reduced capacity of reactive oxygen species (ROS) generation along with elevated expression of antioxidant manganese superoxide dismutase 2 (SOD2). The expression of this antioxidant was also elevated in lung tumor tissue from a worker exposed to Cr(VI) for 19 years. EGFR was activated in Cr(VI)-transformed BEAS-2B cells, lung tissue from animals exposed to Cr(VI) particles, and human lung tumor tissue. Further study indicates that constitutive activation of EGFR in Cr(VI)-transformed cells was due to increased binding to its ligand amphiregulin (AREG). Inhibition of EGFR or AREG increased Bax expression and reduced Bcl-2 expression, resulting in reduced apoptosis resistance. Furthermore, inhibition of AREG or EGFR restored capacity of ROS generation and decreased SOD2 expression. PI3K/AKT was activated, which depended on EGFR in Cr(VI)-transformed BEAS-2B cells. Inhibition of PI3K/AKT increased ROS generation and reduced SOD2 expression, resulting in reduced apoptosis resistance with commitment increase in Bax expression and reduction of Bcl-2 expression. Xenograft mouse tumor study further demonstrates the essential role of EGFR in tumorigenesis of Cr(VI)-transformed cells. In summary, the present study suggests that ligand-dependent constitutive activation of EGFR causes reduced ROS generation and increased antioxidant expression, leading to development of apoptosis resistance, contributing

  6. Transforming growth factor-beta activities in 'in vivo' lines of hormone-dependent and independent mammary adenocarcinomas induced by medroxyprogesterone acetate in BALB/c mice.

    PubMed

    Elizalde, P V; Lanari, C; Kordon, E; Tezón, J; Charreau, E H

    1990-07-01

    We have determined the presence of transforming growth factor-beta (TGF-beta)-like polypeptides in mammary adenocarcinomas induced by medroxyprogesterone acetate (MPA) in BALB/c mice. In hormone-dependent tumors (HD) from nontreated and MPA-treated mice a high molecular weight (43 kDa) transforming activity was purified by Bio-Gel P-60 chromatography. This TGF was able to confer the neoplastic phenotype on NRK-49F cells without the addition of epidermal growth factor (EGF), though its activity was potentiated by EGF. It did not compete for binding to the EGF receptor, had no mitogenic activity on monolayer cultures of NRK fibroblasts, and was a potent inhibitor of DNA synthesis induced in these cells by EGF and insulin. In HD and hormone-independent tumors (HI) another TGF with a Mr of 13 kDa was isolated. This transforming activity showed the same biological properties as 43 kDa TGF, with the exception that in the absence of EGF it did not stimulate soft agar growth of NRK-49F cells. The synthesis of both factors in 'in vivo' HD tumors seems to be under MPA control, since it is much lower in HD tumors from MPA-treated mice. Further purification of the 13 and 43 kDa TGFs by hydrophobic interaction HPLC demonstrated that each one eluted in a different position, and that their elution profile differed from the TGF-beta from human platelets. The biological activity of the 13 and 43 kDa TGFs was not neutralized by a specific anti-TGF-beta antibody. PMID:2145045

  7. Circadian CLOCK Mediates Activation of Transforming Growth Factor-β Signaling and Renal Fibrosis through Cyclooxygenase 2.

    PubMed

    Chen, Wei-Dar; Yeh, Jih-Kai; Peng, Meng-Ting; Shie, Shian-Sen; Lin, Shuei-Liong; Yang, Chia-Hung; Chen, Tien-Hsing; Hung, Kuo-Chun; Wang, Chun-Chieh; Hsieh, I-Chang; Wen, Ming-Shien; Wang, Chao-Yung

    2015-12-01

    The circadian rhythm regulates blood pressure and maintains fluid and electrolyte homeostasis with central and peripheral clock. However, the role of circadian rhythm in the pathogenesis of tubulointerstitial fibrosis remains unclear. Here, we found that the amplitudes of circadian rhythm oscillation in kidneys significantly increased after unilateral ureteral obstruction. In mice that are deficient in the circadian gene Clock, renal fibrosis and renal parenchymal damage were significantly worse after ureteral obstruction. CLOCK-deficient mice showed increased synthesis of collagen, increased oxidative stress, and greater transforming growth factor-β (TGF-β) expression. TGF-β mRNA expression oscillated with the circadian rhythms under the control of CLOCK-BMAL1 heterodimers. The expression of cyclooxygenase 2 was significantly higher in kidneys from CLOCK-deficient mice with ureteral obstruction. Treatment with a cyclooxygenase 2 inhibitor celecoxib significantly improved renal fibrosis in CLOCK-deficient mice. Taken together, these data establish the importance of the circadian rhythm in tubulointerstitial fibrosis and suggest CLOCK/TGF-β signaling as a novel therapeutic target of cyclooxygenase inhibition. PMID:26458764

  8. The bovine papillomavirus type 1 E5 transforming protein specifically binds and activates the beta-type receptor for the platelet-derived growth factor but not other related tyrosine kinase-containing receptors to induce cellular transformation.

    PubMed Central

    Goldstein, D J; Li, W; Wang, L M; Heidaran, M A; Aaronson, S; Shinn, R; Schlegel, R; Pierce, J H

    1994-01-01

    The 44-amino-acid E5 protein of bovine papillomavirus type 1 is a highly hydrophobic protein which appears to transform cells through the activation of growth factor receptors. To investigate the specificity of E5-growth factor receptor interactions required for mitogenic signaling, we utilized a nontumorigenic, murine myeloid cell line (32D) which is strictly dependent on interleukin-3 (IL-3) for sustained proliferation in culture. This IL-3 dependence can be functionally substituted by the expression of a variety of surrogate growth factor receptors and the addition of the corresponding ligand. Several receptor cDNAs for the alpha- and beta-type platelet-derived growth factor receptors [alpha PDGFR and beta PDGFR], the epidermal growth factor receptor, and the colony-stimulating factor 1 receptor) were transfected into 32D cells constitutively expressing the E5 protein to test for IL-3-independent growth. Only beta PDGFR was capable of abrogating the IL-3 dependence of 32D cells. The proliferative signal induced by the coexpression of beta PDGFR and E5 was accompanied by stable complex formation between these proteins, constitutive tyrosine phosphorylation of the receptor, and tumorigenicity in nude mice. The lack of cooperative interaction between E5 and the epidermal growth factor receptor, the colony-stimulating factor 1 receptor, and the highly related alpha PDGFR was paralleled by the inability of E5 to bind to these receptors and failure to increase receptor tyrosine phosphorylation. Thus, these data indicate that the ability of E5 to induce sustained proliferation and transformation of 32D cells is a direct consequence of specific interaction between the E5 protein and the beta PDGFR signaling complex and the subsequent stimulation of receptor tyrosine phosphorylation. Images PMID:8207816

  9. Role of LncRNA-activated by transforming growth factor beta in the progression of hepatitis C virus-related liver fibrosis.

    PubMed

    Fu, Na; Niu, Xuemin; Wang, Yang; Du, Huijuan; Wang, Baoyu; Du, Jinghua; Li, Ya; Wang, Rongqi; Zhang, Yuguo; Zhao, Suxian; Sun, Dianxing; Qiao, Liang; Nan, Yuemin

    2016-08-01

    Long non-coding RNA (LncRNA)-activated by transforming growth factor-beta (LncRNA-ATB) is a key regulator of transforming growth factor-beta (TGF-β) signaling pathway, and is positively correlated with the development of liver cirrhosis and vascular invasion of hepatocellular carcinoma (HCC). However, the role of LncRNA-ATB in hepatitis C virus (HCV)-related liver fibrosis remains largely unknown. In the present study, we confirmed a high expression level of LncRNA-ATB in the liver tissues and plasma samples of patients with HCV-related hepatic fibrosis, and the plasma level of LncRNA-ATB was significantly correlated with liver fibrosis stages. Furthermore, increased expression level of LncRNA-ATB was also present in activated hepatic stellate cells (HSCs), and knockdown of LncRNA-ATB inhibited the expression of alpha-smooth muscle actin (α-SMA) and alpha-1 type I collagen (Col1A1). LncRNA-ATB was found to share the common miRNA responsive element of miR-425-5p with TGF-β type II receptor (TGF-βRII) and SMAD2. Ectopic expression of LncRNA-ATB in HSCs could upregulate the protein expression of TGF-βRII and SMAD2 by inhibiting the endogenous miR-425-5p. Moreover, overexpression of miR-425-5p could partly abrogate the expression of TGF-βRII and SMAD2 induced by LncRNA-ATB. Hence, we conclude that LncRNA-ATB promotes HCV-induced liver fibrogenesis by activating HSCs and increasing collagen I production through competitively binding to miR-425-5p. LncRNA-ATB may be a novel diagnostic biomarker and a potential therapeutic target for HCV-related hepatic fibrosis. PMID:27585228

  10. Inhibition of Transforming Growth Factor-Beta1 SignalingAttenuates Ataxia Telangiectasia Mutated Activity in Response toGenotoxic Stress

    SciTech Connect

    Kirshner, Julia; Jobling, Michael F.; Pajares, Maria Jose; Ravani, Shraddha A.; Glick, Adam; Lavin, Martin F.; Koslov, Sergei; Shiloh, Yosef; Barcellos-Hoff, Mary Helen

    2006-01-01

    Ionizing radiation causes DNA damage that elicits a cellular program of damage control coordinated by the kinase activity of ataxia telangiectasia mutated protein (ATM). Transforming growth factor {beta} (TGF{beta})-1, which is activated by radiation, is a potent and pleiotropic mediator of physiologic and pathologic processes. Here we show that TGF{beta} inhibition impedes the canonical cellular DNA damage stress response. Irradiated Tgf{beta}I null murine epithelial cells or human epithelial cells treated with a small-molecule inhibitor of TGF{beta} type I receptor kinase exhibit decreased phosphorylation of Chk2, Rad17, and p53; reduced H2AX radiation-induced foci; and increased radiosensitivity compared with TGF{beta} competent cells. We determined that loss of TGF{beta} signaling in epithelial cells truncated ATM autophosphorylation and significantly reduced its kinase activity, without affecting protein abundance. Addition of TGF{beta} restored functional ATM and downstream DNA damage responses. These data reveal a heretofore undetected critical link between the microenvironment and ATM, which directs epithelial cell stress responses, cell fate, and tissue integrity. Thus, Tgf{beta}I, in addition to its role in homoeostatic growth control, plays a complex role in regulating responses to genotoxic stress, the failure of which would contribute to the development of cancer; conversely, inhibiting TGF{beta} may be used to advantage in cancer therapy.

  11. Type III Transforming Growth Factor-β Receptor Drives Cardiac Hypertrophy Through β-Arrestin2-Dependent Activation of Calmodulin-Dependent Protein Kinase II.

    PubMed

    Lou, Jie; Zhao, Dan; Zhang, Ling-Ling; Song, Shu-Ying; Li, Yan-Chao; Sun, Fei; Ding, Xiao-Qing; Yu, Chang-Jiang; Li, Yuan-Yuan; Liu, Mei-Tong; Dong, Chang-Jiang; Ji, Yong; Li, Hongliang; Chu, Wenfeng; Zhang, Zhi-Ren

    2016-09-01

    The role of type III transforming growth factor-β receptor (TβRIII) in the pathogenesis of heart diseases remains largely unclear. Here, we investigated the functional role and molecular mechanisms of TβRIII in the development of myocardial hypertrophy. Western blot and quantitative real time-polymerase chain reaction analyses revealed that the expression of TβRIII was significantly elevated in human cardiac hypertrophic samples. Consistently, TβRIII expression was substantially increased in transverse aortic constriction (TAC)- and isoproterenol-induced mouse cardiac hypertrophy in vivo and in isoproterenol-induced cardiomyocyte hypertrophy in vitro. Overexpression of TβRIII resulted in cardiomyocyte hypertrophy, whereas isoproterenol-induced cardiomyocyte hypertrophy was greatly attenuated by knockdown of TβRIII in vitro. Cardiac-specific transgenic expression of TβRIII independently led to cardiac hypertrophy in mice, which was further aggravated by isoproterenol and TAC treatment. Cardiac contractile function of the mice was not altered in TβRIII transgenic mice; however, TAC led to significantly decreased cardiac contractile function in TβRIII transgenic mice compared with control mice. Conversely, isoproterenol- and TAC-induced cardiac hypertrophy and TAC-induced cardiac contractile function impairment were partially reversed by suppression of TβRIII in vivo. Our data suggest that TβRIII mediates stress-induced cardiac hypertrophy through activation of Ca(2+)/calmodulin-dependent protein kinase II, which requires a physical interaction of β-arrestin2 with both TβRIII and calmodulin-dependent protein kinase II. Our findings indicate that stress-induced increase in TβRIII expression results in cardiac hypertrophy through β-arrestin2-dependent activation of calmodulin-dependent protein kinase II and that transforming growth factor-β and β-adrenergic receptor signaling are not involved in spontaneous cardiac hypertrophy in cardiac

  12. Inhibition of mitogen-activated protein kinase kinase, DNA methyltransferase, and transforming growth factor-β promotes differentiation of human induced pluripotent stem cells into enterocytes.

    PubMed

    Kodama, Nao; Iwao, Takahiro; Kabeya, Tomoki; Horikawa, Takashi; Niwa, Takuro; Kondo, Yuki; Nakamura, Katsunori; Matsunaga, Tamihide

    2016-06-01

    We previously reported that small-molecule compounds were effective in generating pharmacokinetically functional enterocytes from human induced pluripotent stem (iPS) cells. In this study, to determine whether the compounds promote the differentiation of human iPS cells into enterocytes, we investigated the effects of a combination of mitogen-activated protein kinase kinase (MEK), DNA methyltransferase (DNMT), and transforming growth factor (TGF)-β inhibitors on intestinal differentiation. Human iPS cells cultured on feeder cells were differentiated into endodermal cells by activin A. These endodermal-like cells were then differentiated into intestinal stem cells by fibroblast growth factor 2. Finally, the cells were differentiated into enterocyte cells by epidermal growth factor and small-molecule compounds. After differentiation, mRNA expression levels and drug-metabolizing enzyme activities were measured. The mRNA expression levels of the enterocyte marker sucrase-isomaltase and the major drug-metabolizing enzyme cytochrome P450 (CYP) 3A4 were increased by a combination of MEK, DNMT, and TGF-β inhibitors. The mRNA expression of CYP3A4 was markedly induced by 1α,25-dihydroxyvitamin D3. Metabolic activities of CYP1A1/2, CYP2B6, CYP2C9, CYP2C19, CYP3A4/5, UDP-glucuronosyltransferase, and sulfotransferase were also observed in the differentiated cells. In conclusion, MEK, DNMT, and TGF-β inhibitors can be used to promote the differentiation of human iPS cells into pharmacokinetically functional enterocytes. PMID:27161454

  13. HCV induces transforming growth factor β1 through activation of endoplasmic reticulum stress and the unfolded protein response

    PubMed Central

    Chusri, Pattranuch; Kumthip, Kattareeya; Hong, Jian; Zhu, Chuanlong; Duan, Xiaoqiong; Jilg, Nikolaus; Fusco, Dahlene N.; Brisac, Cynthia; Schaefer, Esperance A.; Cai, Dachuan; Peng, Lee F.; Maneekarn, Niwat; Lin, Wenyu; Chung, Raymond T.

    2016-01-01

    HCV replication disrupts normal endoplasmic reticulum (ER) function and activates a signaling network called the unfolded protein response (UPR). UPR is directed by three ER transmembrane proteins including ATF6, IRE1, and PERK. HCV increases TGF-β1 and oxidative stress, which play important roles in liver fibrogenesis. HCV has been shown to induce TGF-β1 through the generation of reactive oxygen species (ROS) and p38 MAPK, JNK, ERK1/2, and NFκB-dependent pathways. However, the relationship between HCV-induced ER stress and UPR activation with TGF-β1 production has not been fully characterized. In this study, we found that ROS and JNK inhibitors block HCV up-regulation of ER stress and UPR activation. ROS, JNK and IRE1 inhibitors blocked HCV-activated NFκB and TGF-β1 expression. ROS, ER stress, NFκB, and TGF-β1 signaling were blocked by JNK specific siRNA. Knockdown IRE1 inhibited JFH1-activated NFκB and TGF-β1 activity. Knockdown of JNK and IRE1 blunted JFH1 HCV up-regulation of NFκB and TGF-β1 activation. We conclude that HCV activates NFκB and TGF-β1 through ROS production and induction of JNK and the IRE1 pathway. HCV infection induces ER stress and the UPR in a JNK-dependent manner. ER stress and UPR activation partially contribute to HCV-induced NF-κB activation and enhancement of TGF-β1. PMID:26927933

  14. Transforming Growth Factor-β-Activated Kinase 1 Is Required for Human FcγRIIIb-Induced Neutrophil Extracellular Trap Formation

    PubMed Central

    Alemán, Omar Rafael; Mora, Nancy; Cortes-Vieyra, Ricarda; Uribe-Querol, Eileen; Rosales, Carlos

    2016-01-01

    Neutrophils (PMNs) are the most abundant leukocytes in the blood. PMN migrates from the circulation to sites of infection where they are responsible for antimicrobial functions. PMN uses phagocytosis, degranulation, and formation of neutrophil extracellular traps (NETs) to kill microbes. Several stimuli, including bacteria, fungi, and parasites, and some pharmacological compounds, such as Phorbol 12-myristate 13-acetate (PMA), are efficient inducers of NETs. Antigen–antibody complexes are also capable of inducing NET formation. Recently, it was reported that FcγRIIIb cross-linking induced NET formation similarly to PMA stimulation. Direct cross-linking of FcγRIIA or integrins did not promote NET formation. FcγRIIIb-induced NET formation presented different kinetics from PMA-induced NET formation, suggesting differences in signaling. Because FcγRIIIb also induces a strong activation of extracellular signal-regulated kinase (ERK) and nuclear factor Elk-1, and the transforming growth factor-β-activated kinase 1 (TAK1) has recently been implicated in ERK signaling, in the present report, we explored the role of TAK1 in the signaling pathway activated by FcγRIIIb leading to NET formation. FcγRIIIb was stimulated by specific monoclonal antibodies, and NET formation was evaluated in the presence or absence of pharmacological inhibitors. The antibiotic LL Z1640-2, a selective inhibitor of TAK1 prevented FcγRIIIb-induced, but not PMA-induced NET formation. Both PMA and FcγRIIIb cross-linking induced phosphorylation of ERK. But, LL Z1640-2 only inhibited the FcγRIIIb-mediated activation of ERK. Also, only FcγRIIIb, similarly to transforming growth factor-β-induced TAK1 phosphorylation. A MEK (ERK kinase)-specific inhibitor was able to prevent ERK phosphorylation induced by both PMA and FcγRIIIb. These data show for the first time that FcγRIIIb cross-linking activates TAK1, and that this kinase is required for triggering the MEK/ERK signaling pathway to

  15. Transforming Growth Factor-β-Activated Kinase 1 Is Required for Human FcγRIIIb-Induced Neutrophil Extracellular Trap Formation.

    PubMed

    Alemán, Omar Rafael; Mora, Nancy; Cortes-Vieyra, Ricarda; Uribe-Querol, Eileen; Rosales, Carlos

    2016-01-01

    Neutrophils (PMNs) are the most abundant leukocytes in the blood. PMN migrates from the circulation to sites of infection where they are responsible for antimicrobial functions. PMN uses phagocytosis, degranulation, and formation of neutrophil extracellular traps (NETs) to kill microbes. Several stimuli, including bacteria, fungi, and parasites, and some pharmacological compounds, such as Phorbol 12-myristate 13-acetate (PMA), are efficient inducers of NETs. Antigen-antibody complexes are also capable of inducing NET formation. Recently, it was reported that FcγRIIIb cross-linking induced NET formation similarly to PMA stimulation. Direct cross-linking of FcγRIIA or integrins did not promote NET formation. FcγRIIIb-induced NET formation presented different kinetics from PMA-induced NET formation, suggesting differences in signaling. Because FcγRIIIb also induces a strong activation of extracellular signal-regulated kinase (ERK) and nuclear factor Elk-1, and the transforming growth factor-β-activated kinase 1 (TAK1) has recently been implicated in ERK signaling, in the present report, we explored the role of TAK1 in the signaling pathway activated by FcγRIIIb leading to NET formation. FcγRIIIb was stimulated by specific monoclonal antibodies, and NET formation was evaluated in the presence or absence of pharmacological inhibitors. The antibiotic LL Z1640-2, a selective inhibitor of TAK1 prevented FcγRIIIb-induced, but not PMA-induced NET formation. Both PMA and FcγRIIIb cross-linking induced phosphorylation of ERK. But, LL Z1640-2 only inhibited the FcγRIIIb-mediated activation of ERK. Also, only FcγRIIIb, similarly to transforming growth factor-β-induced TAK1 phosphorylation. A MEK (ERK kinase)-specific inhibitor was able to prevent ERK phosphorylation induced by both PMA and FcγRIIIb. These data show for the first time that FcγRIIIb cross-linking activates TAK1, and that this kinase is required for triggering the MEK/ERK signaling pathway to NETosis

  16. Transforming growth factor beta 1 increases the stability of p21/WAF1/CIP1 protein and inhibits CDK2 kinase activity in human colon carcinoma FET cells.

    PubMed

    Gong, JianGen; Ammanamanchi, Sudhakar; Ko, Tien C; Brattain, Michael G

    2003-06-15

    We examined transforming growth factor-beta 1 (TGF-beta 1) effects on cell cycle progression of human colon carcinoma FET cells. TGF-beta 1 inhibited DNA synthesis and cyclin-dependent kinase (CDK) activity after release from growth arrest in association with induction of the p21 CDK inhibitor, whereas cyclins, CDKs, and p27 protein levels remained relatively unchanged. The decrease in CDK2 kinase activity was the result of increased p21 association with cyclin A-CDK2 and cyclin E-CDK2. TGF-beta 1 treatment in late G(1) showed reduced induction of p21 protein levels in association with increased DNA synthesis. Consequently, p21 induction in early G(1) is critical for TGF-beta 1 inhibition of CDK2 kinase activity. Although TGF-beta 1 treatments in late G(1) failed to induce p21 protein, p21 mRNA induction was observed in late G(1) and in S phase. Further analysis showed that TGF-beta 1 treatment in early G(1) increases p21 protein stability throughout the G(1) and S phases of the cell cycle. Our results demonstrate that TGF-beta 1 stimulation of p21 is regulated at the posttranscriptional and transcriptional levels. This is a novel mechanism of TGF-beta 1 inhibition requiring early G(1) induction and stabilization of p21 protein, which binds to and inhibits cyclin E-CDK2 and cyclin A-CDK2 kinase activity rather than direct modulation of cyclin or CDK protein levels as seen in other systems. PMID:12810668

  17. Cross-Talk between Human Mast Cells and Bronchial Epithelial Cells in Plasminogen Activator Inhibitor-1 Production via Transforming Growth Factor-β1

    PubMed Central

    Lee, Sun H.; Kato, Atsushi; Takabayashi, Tetsuji; Kulka, Marianna; Shin, Soon C.; Schleimer, Robert P.

    2015-01-01

    Previous reports suggest that plasminogen activator inhibitor-1 (PAI-1) promotes airway remodeling and that human and mouse mast cells (MCs) are an important source of PAI-1. In the present study we investigated MC–epithelial cell (EC) interactions in the production of PAI-1. We stimulated the human MC line LAD2 with IgE-receptor cross-linking and collected the supernatants. We incubated the human bronchial EC line BEAS-2B with the LAD2 supernatants and measured the level of PAI-1. When the supernatants from IgE-stimulated LAD2 were added to BEAS-2B, there was a significant enhancement of PAI-1 production by BEAS-2B. When we treated the MC supernatants with a transforming growth factor (TGF)-β1 neutralizing antibody, the MC-derived induction of PAI-1 from BEAS-2B was completely abrogated. Although TGF-β1 mRNA was constitutively expressed in resting LAD2, it was not highly induced by IgE-mediated stimulation. Nonetheless, active TGF-β1 protein was significantly increased in LAD2 after IgE-mediated stimulation. Active TGF-β1 produced by primary cultured human MCs was significantly reduced in the presence of a chymase inhibitor, suggesting a role of MC chymase as an activator of latent TGF-β1. This study indicates that stimulation of human MCs by IgE receptor cross-linking triggers activation of TGF-β1, at least in part via chymase, which in turn induces the production of PAI-1 by bronchial ECs. Our data suggest that human MCs may play an important role in airway remodeling in asthma as a direct source of PAI-1 and by activating bronchial ECs to produce further PAI-1 via a TGF-β1–mediated activation pathway. PMID:24987792

  18. Cross-talk between human mast cells and bronchial epithelial cells in plasminogen activator inhibitor-1 production via transforming growth factor-β1.

    PubMed

    Cho, Seong H; Lee, Sun H; Kato, Atsushi; Takabayashi, Tetsuji; Kulka, Marianna; Shin, Soon C; Schleimer, Robert P

    2015-01-01

    Previous reports suggest that plasminogen activator inhibitor-1 (PAI-1) promotes airway remodeling and that human and mouse mast cells (MCs) are an important source of PAI-1. In the present study we investigated MC-epithelial cell (EC) interactions in the production of PAI-1. We stimulated the human MC line LAD2 with IgE-receptor cross-linking and collected the supernatants. We incubated the human bronchial EC line BEAS-2B with the LAD2 supernatants and measured the level of PAI-1. When the supernatants from IgE-stimulated LAD2 were added to BEAS-2B, there was a significant enhancement of PAI-1 production by BEAS-2B. When we treated the MC supernatants with a transforming growth factor (TGF)-β1 neutralizing antibody, the MC-derived induction of PAI-1 from BEAS-2B was completely abrogated. Although TGF-β1 mRNA was constitutively expressed in resting LAD2, it was not highly induced by IgE-mediated stimulation. Nonetheless, active TGF-β1 protein was significantly increased in LAD2 after IgE-mediated stimulation. Active TGF-β1 produced by primary cultured human MCs was significantly reduced in the presence of a chymase inhibitor, suggesting a role of MC chymase as an activator of latent TGF-β1. This study indicates that stimulation of human MCs by IgE receptor cross-linking triggers activation of TGF-β1, at least in part via chymase, which in turn induces the production of PAI-1 by bronchial ECs. Our data suggest that human MCs may play an important role in airway remodeling in asthma as a direct source of PAI-1 and by activating bronchial ECs to produce further PAI-1 via a TGF-β1-mediated activation pathway. PMID:24987792

  19. Transforming growth factor beta (TGFB) signaling is activated during porcine implantation: proposed role for latency-associated peptide interactions with integrins at the conceptus-maternal interface.

    PubMed

    Massuto, Dana A; Kneese, Eric C; Johnson, Gregory A; Burghardt, Robert C; Hooper, R Neil; Ing, Nancy H; Jaeger, Laurie A

    2010-02-01

    The process of implantation is mediated by a complex network of signaling and adhesive factors. In the pig, latent and active transforming growth factor beta (TGFB), TGFB receptors (TGFBR), and integrins (ITGs) are present during the peri-implantation period. TGFB signals via TGFBR and activates downstream effector SMAD proteins 2 and 3 (p-SMAD2/3). Latency-associated peptide (LAP), part of the latent TGFB complex, is known to bind to ITG heterodimers and activate TGFB. We hypothesize that active TGFBs and TGFBRs along with LAP and ITGs functionally interact at the conceptus-maternal interface to mediate events essential for conceptus development and attachment in pigs. Uteri and conceptuses from days 10, 12, 16, 20, and 24 pregnant gilts were immunostained for TGFB, LAP, and ITG subunits (ITGAV, ITGB1, ITGB3, ITGB5, ITGB6, and ITGB8). Activation of TGFBRs was evaluated by the presence of phosphorylated downstream effector SMAD2/3. Binding of LAP to ITGs was also evaluated using porcine trophectoderm cells. Abundant active TGFB was detected at the apical surfaces of epithelia at the conceptus-maternal interface, and p-SMAD2/3 was detected at both conceptus attachment and nonattachment sites during implantation. Separate aggregates of LAP, ITGB1, ITGB5, and later ITGB3 were detected at the porcine conceptus-maternal interface, and binding of LAP to ITGs on apical surfaces was demonstrated. Results suggest that functional LAP-ITG adhesion complexes support conceptus attachment and promote TGFB activation leading to TGFB interaction with TGFBR supporting events of porcine implantation. PMID:19920116

  20. Nod-like receptor protein 3 inflammasome activation by Escherichia coli RNA induces transforming growth factor beta 1 secretion in hepatic stellate cells

    PubMed Central

    Wang, Hui; Liu, Shu; Wang, Ying; Chang, Bing; Wang, Bingyuan

    2016-01-01

    Nod-like receptor protein 3 (NLRP3) inflammasome has been implicated in alcoholic liver disease. Chronic alcohol consumption enhances gut permeability and causes microbial translocation. The present study explored the activation of the NLRP3 inflammasome by Escherichia coli RNA in hepatic stellate cells (HSCs), and the potential role of NLRP3 inflammasome in hepatic fibrosis. E. coli RNA transfection induced HSC-T6 cells to secrete and express mature interleukin-1 beta (IL-1β), which was abolished by NLRP3 siRNA pretreatment. In addition, E. coli RNA transfection enhanced caspase-1 expression, whereas reduced caspase-1 precursor (pro-caspase-1) expression. E. coli RNA-stimulated transforming growth factor beta 1 (TGF-β1) overproduction in HSC-T6 cells, which was blocked by recombinant IL-1 receptor antagonist (rIL-1Ra) or nuclear factor κB inhibitor BAY 11-7082. Furthermore, E. coli RNA-induced overexpression of pro-fibrogenic factors was suppressed by rIL-1Ra or TGF-β receptor inhibitor A83-01. These results demonstrate that E. coli RNA can stimulate NLRP3 inflammasome activation, which leads to excessive production of pro-fibrogenic factors, suggesting that NLRP3 inflammasome activation in HSCs may play a role in hepatic fibrosis. PMID:26773180

  1. Transforming growth factor β-activated kinase 1 negatively regulates interleukin-1α-induced stromal-derived factor-1 expression in vascular smooth muscle cells

    SciTech Connect

    Yang, Bin; Li, Wei; Zheng, Qichang; Qin, Tao; Wang, Kun; Li, Jinjin; Guo, Bing; Yu, Qihong; Wu, Yuzhe; Gao, Yang; Cheng, Xiang; Hu, Shaobo; Kumar, Stanley Naveen; Liu, Sanguang; Song, Zifang

    2015-07-17

    Stromal-derived Factor-1 (SDF-1) derived from vascular smooth muscle cells (VSMCs) contributes to vascular repair and remodeling in various vascular diseases. In this study, the mechanism underlying regulation of SDF-1 expression by interleukin-1α (IL-1α) was investigated in primary rat VSMCs. We found IL-1α promotes SDF-1 expression by up-regulating CCAAT-enhancer-binding protein β (C/EBPβ) in an IκB kinase β (IKKβ) signaling-dependent manner. Moreover, IL-1α-induced expression of C/EBPβ and SDF-1 was significantly potentiated by knockdown of transforming growth factor β-activated kinase 1 (TAK1), an upstream activator of IKKβ signaling. In addition, we also demonstrated that TAK1/p38 mitogen-activated protein kinase (p38 MAPK) signaling exerted negative effect on IL-1α-induced expression of C/EBPβ and SDF-1 through counteracting ROS-dependent up-regulation of nuclear factor erythroid 2-related factor 2 (NRF2). In conclusion, TAK1 acts as an important regulator of IL-1α-induced SDF-1 expression in VSMCs, and modulating activity of TAK1 may serve as a potential strategy for modulating vascular repair and remodeling. - Highlights: • IL-1α induces IKKβ signaling-dependent SDF-1 expression by up-regulating C/EBPβ. • Activation of TAK1 by IL-1α negatively regulates C/EBPβ-dependent SDF-1 expression. • IL-1α-induced TAK1/p38 MAPK signaling counteracts ROS-dependent SDF-1 expression. • TAK1 counteracts IL-1α-induced SDF-1 expression by attenuating NRF2 up-regulation.

  2. Sorting nexin 9 differentiates ligand-activated Smad3 from Smad2 for nuclear import and transforming growth factor β signaling

    PubMed Central

    Wilkes, Mark C.; Repellin, Claire E.; Kang, Jeong-Han; Andrianifahanana, Mahefatiana; Yin, Xueqian; Leof, Edward B.

    2015-01-01

    Transforming growth factor β (TGFβ) is a pleiotropic protein secreted from essentially all cell types and primary tissues. While TGFβ’s actions reflect the activity of a number of signaling networks, the primary mediator of TGFβ responses are the Smad proteins. Following receptor activation, these cytoplasmic proteins form hetero-oligomeric complexes that translocate to the nucleus and affect gene transcription. Here, through biological, biochemical, and immunofluorescence approaches, sorting nexin 9 (SNX9) is identified as being required for Smad3-dependent responses. SNX9 interacts with phosphorylated (p) Smad3 independent of Smad2 or Smad4 and promotes more rapid nuclear delivery than that observed independent of ligand. Although SNX9 does not bind nucleoporins Nup153 or Nup214 or some β importins (Imp7 or Impβ), it mediates the association of pSmad3 with Imp8 and the nuclear membrane. This facilitates nuclear translocation of pSmad3 but not SNX9. PMID:26337383

  3. Transforming growth factor-β inhibits IQ motif containing guanosine triphosphatase activating protein 1 expression in lung fibroblasts via the nuclear factor-κB signaling pathway.

    PubMed

    Zong, Chuanyue; Zhang, Xianlong; Xie, Ying; Cheng, Jiawen

    2015-07-01

    IQ motif containing guanosine triphosphatase activating protein 1 (IQGAP1) is associated with idiopathic pulmonary fibrogenesis (IPF); however, characterization of the expression of IQGAP1 in lung fibroblasts has remained elusive. The present study therefore evaluated IQGAP1 expression in mouse and human lung fibroblasts under fibrotic conditions via western blot analysis. It was revealed that IQGAP1 expression levels were significantly decreased in lung fibroblasts isolated from bleomycin-challenged mice than in those of control mice. Transforming growth factor-β (TGF-β) induced differentiation, as well as decreased expression of IQGAP1 in WI-38 cells human lung fibroblasts. Furthermore, inhibition of nuclear factor (NF)-κB activation restored the TGF-β-induced inhibition of IQGAP1 expression in WI-38 cells. In lysophosphatidic acid (LPA)-challenged WI-38 cells, the expression of IQGAP1 was also decreased, while neutralized anti-TGF-β antibody treatment restored the LPA-induced inhibition of IQGAP1 expression. These data indicated that TGF-β inhibited IQGAP1 expression in lung fibroblasts via the NF-κB signaling pathway, presenting a potential novel therapeutic target for the treatment of IPF. PMID:25684348

  4. Transforming Growth Factor β1 (TGF-β1) Activates Hepcidin mRNA Expression in Hepatocytes.

    PubMed

    Chen, Simeng; Feng, Teng; Vujić Spasić, Maja; Altamura, Sandro; Breitkopf-Heinlein, Katja; Altenöder, Jutta; Weiss, Thomas S; Dooley, Steven; Muckenthaler, Martina U

    2016-06-17

    The hepatic hormone hepcidin is the master regulator of systemic iron homeostasis. Its expression level is adjusted to alterations in iron levels, inflammatory cues, and iron requirements for erythropoiesis. Bone morphogenetic protein 6 (BMP6) contributes to the iron-dependent control of hepcidin. In addition, TGF-β1 may stimulate hepcidin mRNA expression in murine hepatocytes and human leukocytes. However, receptors and downstream signaling proteins involved in TGF-β1-induced hepcidin expression are still unclear. Here we show that TGF-β1 treatment of mouse and human hepatocytes, as well as ectopic expression of TGF-β1 in mice, increases hepcidin mRNA levels. The hepcidin response to TGF-β1 depends on functional TGF-β1 type I receptor (ALK5) and TGF-β1 type II receptor (TβRII) and is mediated by a noncanonical mechanism that involves Smad1/5/8 phosphorylation. Interestingly, increasing availability of canonical Smad2/3 decreases TGF-β1-induced hepcidin regulation, whereas the BMP6-hepcidin signal was enhanced, indicating a signaling component stoichiometry-dependent cross-talk between the two pathways. Although ALK2/3-dependent hepcidin activation by BMP6 can be modulated by each of the three hemochromatosis-associated proteins: HJV (hemojuvelin), HFE (hemochromatosis protein), and TfR2 (transferrin receptor 2), these proteins do not control the ALK5-mediated hepcidin response to TGF-β1. TGF-β1 mRNA levels are increased in mouse models of iron overload, indicating that TGF-β1 may contribute to hepcidin synthesis under these conditions. In conclusion, these data demonstrate that a complex regulatory network involving TGF-β1 and BMP6 may control the sensing of systemic and/or hepatic iron levels. PMID:27129231

  5. The immunomodulatory activity of human amniotic fluid can be correlated with transforming growth factor-beta 1 (TGF-beta 1) and beta 2 activity.

    PubMed Central

    Lang, A K; Searle, R F

    1994-01-01

    The role of alphafetoprotein (AFP) in the immunomodulatory activity of amniotic fluids (AF) from normally progressing human pregnancy (weeks 14-16) was investigated. A panel of 42 AF (25% v/v) reduced significantly phytohaemagglutinin (PHA)-induced peripheral blood mononuclear cell (PBMC) proliferation in serum-free cultures with a mean per cent inhibition of 68.4 +/- 5.5%. In contrast, AFP preparations, with one exception (U.AFP), failed to display inhibitory activity. Pretreatment of AF with anti-TGF-beta 1 and beta 2 antibodies used alone resulted in the mean per cent loss of inhibition of 33.1 +/- 3.9% and 52.3 +/- 7.5%, respectively. A summative loss of AF-mediated inhibition was detected when anti-TGF-beta 1 and beta 2 antibodies were used in combination, but immunomodulation was rarely abolished 100% by this treatment. Anti-TGF-beta 2 antibody treatment, unlike anti-TGF-beta 1 antibody treatment, reversed the inhibitory activity of U.AFP. The amount of TGF-beta 1 and beta 2 contained in human AF was studied by growth inhibition of Mv1 Lu cells. The mean levels of TGF-beta 1 and beta 2 in AF were 11 +/- 0.9 U/ml and 2.3 +/- 0.4 U/ml, respectively, which corresponds with a mean per cent inhibition of 49 +/- 4.7%. U.AFP also significantly inhibited Mv1 Lu cell growth. To investigate the mechanism of AF-mediated inhibition, the effect of AF and AFP on IL-2 production by concanavalin A (Con A)-stimulated PBMC blasts was determined by the CTLL-2 cell bioassay. IL-2 production was reduced 55.5% in AF-treated blasts and 61% in U.AFP-treated blasts compared with controls. Our findings indicate that the immunomodulatory activity of human AF can be correlated with TGF-beta 1 and beta 2 and not with AFP, the inhibitory activity of U.AFP preparation reflecting copurifying TGF-beta 2 activity. PMID:7518368

  6. Co-expression of the protease furin in Nicotiana benthamiana leads to efficient processing of latent transforming growth factor-β1 into a biologically active protein.

    PubMed

    Wilbers, Ruud H P; Westerhof, Lotte B; van Raaij, Debbie R; van Adrichem, Marloes; Prakasa, Andreas D; Lozano-Torres, Jose L; Bakker, Jaap; Smant, Geert; Schots, Arjen

    2016-08-01

    Transforming growth factor beta (TGF-β) is a signalling molecule that plays a key role in developmental and immunological processes in mammals. Three TGF-β isoforms exist in humans, and each isoform has unique therapeutic potential. Plants offer a platform for the production of recombinant proteins, which is cheap and easy to scale up and has a low risk of contamination with human pathogens. TGF-β3 has been produced in plants before using a chloroplast expression system. However, this strategy requires chemical refolding to obtain a biologically active protein. In this study, we investigated the possibility to transiently express active human TGF-β1 in Nicotiana benthamiana plants. We successfully expressed mature TGF-β1 in the absence of the latency-associated peptide (LAP) using different strategies, but the obtained proteins were inactive. Upon expression of LAP-TGF-β1, we were able to show that processing of the latent complex by a furin-like protease does not occur in planta. The use of a chitinase signal peptide enhanced the expression and secretion of LAP-TGF-β1, and co-expression of human furin enabled the proteolytic processing of latent TGF-β1. Engineering the plant post-translational machinery by co-expressing human furin also enhanced the accumulation of biologically active TGF-β1. This engineering step is quite remarkable, as furin requires multiple processing steps and correct localization within the secretory pathway to become active. Our data demonstrate that plants can be a suitable platform for the production of complex proteins that rely on specific proteolytic processing. PMID:26834022

  7. A Cationic-Independent Mannose 6-Phosphate Receptor Inhibitor (PXS64) Ameliorates Kidney Fibrosis by Inhibiting Activation of Transforming Growth Factor-β1

    PubMed Central

    Zhang, Jie; Wong, Muh Geot; Wong, May; Gross, Simon; Chen, Jason; Pollock, Carol; Saad, Sonia

    2015-01-01

    The activity of transforming growth factor-β1 (TGF-β1) is regulated by its conversion from the latent to the active form. We have previously shown that the conversion is at least in part mediated by the cationic-independent mannose 6-phosphate receptor (CI-M6PR), as the CI-M6PR inhibitor, PXS-25 has anti-fibrotic properties in human kidney tubular (HK-2) cells under high glucose conditions. However, its clinical use is limited by low bioavailability. Our aim was to determine the effects of PXS64, a pro-drug of PXS25, in in vitro and in vivo models of renal fibrosis. HK-2 cells were exposed to latent TGFβ1+/- PXS64 for 48 hours. The mRNA and protein levels of pro-fibrotic and pro-inflammatory markers were determined. A 7 day unilateral ureteric obstruction (UUO) model was used and the following experimental groups were studied: (i) Sham operated, (ii) UUO, (iii) UUO + telmisartan (iv) UUO + PSX64. HK-2 cells exposed to PXS64 reduced TGFβ mediated effects on collagen IV, fibronectin, macrophage chemotactic protein-1 (MCP-1) and phospho-smad2 protein expression, consistent with inhibition of the conversion of latent to active TGF-β1. PXS 64 treated UUO mice had a lower tubulointerstitial fibrosis index, collagen IV and fibronectin protein and mRNA expression when compared to untreated UUO mice. In addition, these animals had lower MCP-1 mRNA expression, reduced inflammarory cell infiltrate, as indicated by fewer CD45, F4/80 positive cells, and reduced phospho-Smad2 protein expression when compared to untreated UUO animals. Our data demonstrates that PSX64 is an effective anti-fibrotic agent by inhibiting the activation of latent TGF-β1. PMID:25658916

  8. Essential Roles of RNA-binding Protein HuR in Activation of Hepatic Stellate Cells Induced by Transforming Growth Factor-β1

    PubMed Central

    Ge, Jingjing; Chang, Na; Zhao, Zhongxin; Tian, Lei; Duan, Xianghui; Yang, Lin; Li, Liying

    2016-01-01

    RNA-binding protein HuR mediates transforming growth factor (TGF)-β1-induced profibrogenic actions. Up-regulation of Sphingosine kinase 1 (SphK1) is involved in TGF-β1-induced activation of hepatic stellate cells (HSCs) in liver fibrogenesis. However, the molecular mechanism of TGF-β1 regulates SphK1 remains unclear. This study was designed to investigate the role of HuR in TGF-β1-induced SphK1 expression and identify a new molecular mechanism in liver fibrogenensis. In vivo, HuR expression was increased, translocated to cytoplasm, and bound to SphK1 mRNA in carbon tetrachloride- and bile duct ligation-induced mouse fibrotic liver. HuR mRNA expression had a positive correlation with mRNA expressions of SphK1 and fibrotic markers, α-smooth muscle actin (α-SMA) and Collagen α1(I), respectively. In vitro, up-regulation of SphK1 and activation of HSCs stimulated by TGF-β1 depended on HuR cytoplasmic accumulation. The effects of TGF-β1 were diminished when HuR was silenced or HuR cytoplasmic translocation was blocked. Meanwhile, overexpression of HuR mimicked the effects of TGF-β1. Furthermore, TGF-β1 prolonged half-life of SphK1 mRNA by promoting its binding to HuR. Pharmacological or siRNA-induced SphK1 inhibition abrogated HuR-mediated HSC activation. In conclusion, our data suggested that HuR bound to SphK1 mRNA and played a crucial role in TGF-β1-induced HSC activation. PMID:26912347

  9. Extracellular domain dependence of PTPα transforming activity

    PubMed Central

    Zheng, Xinmin; Holsinger, Leslie J.; Shalloway, David

    2016-01-01

    Two isoforms of the transmembrane protein tyrosine phosphatase PTPα, which differ by nine amino acids in their extracellular regions, are expressed in a tissue-specific manner. Over-expression of the shorter isoform transforms rodent cells, and it has previously been reasonable to assume that this was a direct consequence of its dephosphorylation and activation of Src. Transformation by the longer wild-type isoform has not previously been studied. We tested the activities of both isoforms in NIH3T3 cells and found that, while both dephosphorylated and activated Src similarly, only the shorter isoform induced focus formation or anchorage-independent growth. Differences in phosphorylation of PTPα at its known regulatory sites, Grb2 binding to PTPα, phosphorylation level of focal adhesion kinase by PTPα, or overall localization were excluded as possible explanations for the differences in transforming activities. The results suggest that transformation by PTPα involves at least one function other than, or in addition to, its activation of Src and that this depends on PTPα’s extracellular domain. Previous studies have suggested that PTPα might be a useful target in breast and colon cancer therapy, and the results presented here suggest that it may be advantageous to develop isoform-specific therapeutic reagents. PMID:20545765

  10. RB1CC1 Protein Positively Regulates Transforming Growth Factor-β Signaling through the Modulation of Arkadia E3 Ubiquitin Ligase Activity*

    PubMed Central

    Koinuma, Daizo; Shinozaki, Masahiko; Nagano, Yoshiko; Ikushima, Hiroaki; Horiguchi, Kana; Goto, Kouichiro; Chano, Tokuhiro; Saitoh, Masao; Imamura, Takeshi; Miyazono, Kohei; Miyazawa, Keiji

    2011-01-01

    Transforming growth factor-β (TGF-β) signaling is controlled by a variety of regulators, of which Smad7, c-Ski, and SnoN play a pivotal role in its negative regulation. Arkadia is a RING-type E3 ubiquitin ligase that targets these negative regulators for degradation to enhance TGF-β signaling. In the present study we identified a candidate human tumor suppressor gene product RB1CC1/FIP200 as a novel positive regulator of TGF-β signaling that functions as a substrate-selective cofactor of Arkadia. Overexpression of RB1CC1 enhanced TGF-β signaling, and knockdown of endogenous RB1CC1 attenuated TGF-β-induced expression of target genes as well as TGF-β-induced cytostasis. RB1CC1 down-regulated the protein levels of c-Ski but not SnoN by enhancing the activity of Arkadia E3 ligase toward c-Ski. Substrate selectivity is primarily attributable to the physical interaction of RB1CC1 with substrates, suggesting its role as a scaffold protein. RB1CC1 thus appears to play a unique role as a modulator of TGF-β signaling by restricting substrate specificity of Arkadia. PMID:21795712

  11. Lactic Acid is Elevated in Idiopathic Pulmonary Fibrosis and Induces Myofibroblast Differentiation Via pH-Dependent Activation of Transforming Growth Factor-β

    SciTech Connect

    Kottman, R. M.; Kulkarni, Ajit A.; Smolnycki, Katie A.; Lyda, Elizabeth; Dahanayake, Thinesh; Salibi, Rami; Honnons, Sylvie; Jones, Carolyn; Isern, Nancy G.; Hu, Jian Z.; Nathan, Steven D.; Grant, Geraldine; Phipps, Richard P.; Sime, Patricia J.

    2012-10-15

    Rationale: Idiopathic pulmonary fibrosis (IPF) is a complex disease for which the pathogenesis is poorly understood. In this study, we identified lactic acid as a metabolite that is elevated in the lung tissue of patients with IPF. Objectives: This study examines the effect of lactic acid on myofibroblast differentiation and pulmonary fibrosis. Methods:We used metabolomic analysis to examine cellular metabolism in lung tissuefrom patients with IPFanddeterminedthe effects of lactic acid and lactate dehydrogenase-5 (LDH5) overexpression on myofibroblast differentiation and transforming growth factor (TGF)-b activation in vitro. Measurements and Main Results: Lactic acid concentrations from healthy and IPF lung tissue were determined by nuclear magnetic resonance spectroscopy; a-smooth muscle actin, calponin, and LDH5 expression were assessed by Western blot of cell culture lysates. Lactic acid and LDH5 were significantly elevated in IPF lung tissue compared with controls. Physiologic concentrations of lactic acid induced myofibroblast differentiation via activation of TGF-b. TGF-b induced expression of LDH5 via hypoxia-inducible factor 1a (HIF1a). Importantly, overexpression of both HIF1a and LDH5 in human lung fibroblasts induced myofibroblast differentiation and synergized with low dose TGF-b to induce differentiation. Furthermore, inhibition of both HIF1a and LDH5 inhibited TGF-b–induced myofibroblast differentiation. Conclusions: We have identified the metabolite lactic acid as an important mediator of myofibroblast differentiation via a pHdependent activation of TGF-b. We propose that the metabolic milieu of the lung, and potentially other tissues, is an important driving force behind myofibroblast differentiation and potentially the initiation and progression of fibrotic disorders.

  12. Transcriptional activation of mouse mast cell Protease-7 by activin and transforming growth factor-beta is inhibited by microphthalmia-associated transcription factor.

    PubMed

    Funaba, Masayuki; Ikeda, Teruo; Murakami, Masaru; Ogawa, Kenji; Tsuchida, Kunihiro; Sugino, Hiromu; Abe, Matanobu

    2003-12-26

    Previous studies have revealed that activin A and transforming growth factor-beta1 (TGF-beta1) induced migration and morphological changes toward differentiation in bone marrow-derived cultured mast cell progenitors (BMCMCs). Here we show up-regulation of mouse mast cell protease-7 (mMCP-7), which is expressed in differentiated mast cells, by activin A and TGF-beta1 in BMCMCs, and the molecular mechanism of the gene induction of mmcp-7. Smad3, a signal mediator of the activin/TGF-beta pathway, transcriptionally activated mmcp-7. Microphthalmia-associated transcription factor (MITF), a tissue-specific transcription factor predominantly expressed in mast cells, melanocytes, and heart and skeletal muscle, inhibited Smad3-mediated mmcp-7 transcription. MITF associated with Smad3, and the C terminus of MITF and the MH1 and linker region of Smad3 were required for this association. Complex formation between Smad3 and MITF was neither necessary nor sufficient for the inhibition of Smad3 signaling by MITF. MITF inhibited the transcriptional activation induced by the MH2 domain of Smad3. In addition, MITF-truncated N-terminal amino acids could associate with Smad3 but did not inhibit Smad3-mediated transcription. The level of Smad3 was decreased by co-expression of MITF but not of dominant-negative MITF, which resulted from proteasomal protein degradation. The changes in the level of Smad3 protein were paralleled by those in Smad3-mediated signaling activity. These findings suggest that MITF negatively regulates Smad-dependent activin/TGF-beta signaling in a tissue-specific manner. PMID:14527958

  13. Transforming growth factor-{beta} inhibits CCAAT/enhancer-binding protein expression and PPAR{gamma} activity in unloaded bone marrow stromal cells

    SciTech Connect

    Ahdjoudj, S.; Kaabeche, K.; Holy, X.; Fromigue, O.; Modrowski, D.; Zerath, E.; Marie, P.J. . E-mail: pierre.marie@larib.inserm.fr

    2005-02-01

    The molecular mechanisms regulating the adipogenic differentiation of bone marrow stromal cells in vivo remain largely unknown. In this study, we investigated the regulatory effects of transforming growth factor beta-2 (TGF-{beta}2) on transcription factors involved in adipogenic differentiation induced by hind limb suspension in rat bone marrow stromal cells in vivo. Time course real-time quantitative reverse-transcription polymerase chain reaction (RT-PCR) analysis of gene expression showed that skeletal unloading progressively increases the expression of CCAAT/enhancer-binding protein (C/EBP){alpha} and C/EBP{beta} {alpha} at 5 days in bone marrow stromal cells resulting in increased peroxisome proliferator-activated receptor {gamma} (PPAR{gamma}2) transcripts at 7 days. TGF-{beta}2 administration in unloaded rats corrected the rise in C/EBP{alpha} and C/EBP{beta} transcripts induced by unloading in bone marrow stromal cells. This resulted in inhibition of PPAR{gamma}2 expression that was associated with increased Runx2 expression. Additionally, the inhibition of C/EBP{alpha} and C/EBP{beta} expression by TGF-{beta}2 was associated with increased PPAR{gamma} serine phosphorylation in bone marrow stromal cells, a mechanism that inhibits PPAR{gamma} transactivating activity. The sequential inhibitory effect of TGF-{beta}2 on C/EBP{alpha}, C/EBP{beta}, and PPAR{gamma}2 resulted in reduced LPL expression and abolition of bone marrow stromal cell adipogenic differentiation, which contributed to prevent bone loss induced by skeletal unloading. We conclude that TGF-{beta}2 inhibits the excessive adipogenic differentiation of bone marrow stromal cells induced by skeletal unloading by inhibiting C/EBP{alpha}, C/EBP{beta}, and PPAR{gamma} expression and activity, which provides a sequential mechanism by which TGF-{beta}2 regulates adipogenic differentiation of bone marrow stromal cells in vivo.

  14. Inhibition of Plasminogen Activator Inhibitor-1 Attenuates Transforming Growth Factor-β-Dependent Epithelial Mesenchymal Transition and Differentiation of Fibroblasts to Myofibroblasts

    PubMed Central

    Omori, Keitaro; Hattori, Noboru; Senoo, Tadashi; Takayama, Yusuke; Masuda, Takeshi; Nakashima, Taku; Iwamoto, Hiroshi; Fujitaka, Kazunori; Hamada, Hironobu; Kohno, Nobuoki

    2016-01-01

    Transforming growth factor-β (TGF-β) is central during the pathogenesis of pulmonary fibrosis, in which the plasminogen activator inhibitor-1 (PAI-1) also has an established role. TGF-β is also known to be the strongest inducer of PAI-1. To investigate the link between PAI-1 and TGF-β in fibrotic processes, we evaluated the effect of SK-216, a PAI-1-specific inhibitor, in TGF-β-dependent epithelial-mesenchymal transition (EMT) and fibroblast to myofibroblast differentiation. In human alveolar epithelial A549 cells, treatment with TGF-β induced EMT, whereas co-treatment with SK-216 attenuated the occurrence of EMT. The inhibition of TGF-β-induced EMT by SK-216 was also confirmed in the experiment using murine epithelial LA-4 cells. Blocking EMT by SK-216 inhibited TGF-β-induced endogenous production of PAI-1 and TGF-β in A549 cells as well. These effects of SK-216 were not likely mediated by suppressing either Smad or ERK pathways. Using human lung fibroblast MRC-5 cells, we demonstrated that SK-216 inhibited TGF-β-dependent differentiation of fibroblasts to myofibroblasts. We also observed this inhibition by SK-216 in human primary lung fibroblasts. Following these in vitro results, we tested oral administration of SK-216 into mice injected intratracheally with bleomycin. We found that SK-216 reduced the degree of bleomycin-induced pulmonary fibrosis in mice. Although the precise mechanisms underlying the link between TGF-β and PAI-1 regarding fibrotic process were not determined, PAI-1 seems to act as a potent downstream effector on the pro-fibrotic property of TGF-β. In addition, inhibition of PAI-1 activity by a PAI-1 inhibitor exerts an antifibrotic effect even in vivo. These data suggest that targeting PAI-1 as a downstream effector of TGF-β could be a promising therapeutic strategy for pulmonary fibrosis. PMID:26859294

  15. The inhibition of transforming growth factor beta-activated kinase 1 contributed to neuroprotection via inflammatory reaction in pilocarpine-induced rats with epilepsy.

    PubMed

    Tian, Q; Xiao, Q; Yu, W; Gu, M; Zhao, N; Lü, Y

    2016-06-14

    Recently, more and more studies support that inflammation is involved in the pathogenesis of epilepsy. Although TGFβ signaling is involved in epileptogenesis, whether TGFβ-associated neuroinflammation is sufficient to regulate epilepsy remains unknown to date. Furthermore, tumor necrosis factor-α receptor-associated factor-6 (TRAF6), transforming growth factor beta-activated kinase 1 (TAK1), which are the key elements of TGFβ-associated inflammation, is still unclear in epilepsy. Therefore, the present study aimed to explore the role of TRAF6 and TAK1 in pilocarpine-induced epileptic rat model. Firstly, the gene levels and protein expression of TRAF6 and TAK1 were detected in different time points after pilocarpine-induced status epilepticus (SE). 5z-7-oxozeaenol treatment (TAK1 antagonist) was then performed; the changes in TRAF6, TAK1, phosphorylated-TAK1 (P-TAK1), interleukin-1β (IL-1β) levels, neuronal survival and apoptosis, and seizure activity were detected. Our results showed that expressions of TRAF6 were increased after SE, reached the peak in 7day, maintained at the high level to 30days, and the TAK1, P-TAK1 levels were increased after SE following time. After 5z-7-oxozeaenol treatment in epileptic rats, TRAF6-TAK1-P-TAK1 signaling protein expressions were reduced, inflammatory cytokine IL-1β expression was decreased, neuron survival index was improved, the neuron apoptosis index was decreased and seizure durations were alleviated. In conclusion, the expression of TRAF6 and TAK1 are related to the progression of epilepsy. TAK1 might be a potential intervention target for the treatment of epilepsy via neuroprotection. PMID:27012613

  16. Inhibition of liver fibrosis by solubilized coenzyme Q10: Role of Nrf2 activation in inhibiting transforming growth factor-beta1 expression

    SciTech Connect

    Choi, Hoo-Kyun; Pokharel, Yuba Raj; Lim, Sung Chul; Han, Hyo-Kyung; Ryu, Chang Seon; Kim, Sang Kyum; Kwak, Mi Kyong; Kang, Keon Wook

    2009-11-01

    Coenzyme Q10 (CoQ10), an endogenous antioxidant, is important in oxidative phosphorylation in mitochondria. It has anti-diabetic and anti-cardiovascular disease effects, but its ability to protect against liver fibrosis has not been studied. Here, we assessed the ability of solubilized CoQ10 to improve dimethylnitrosamine (DMN)-induced liver fibrogenesis in mice. DMN treatments for 3 weeks produced a marked liver fibrosis as assessed by histopathological examination and tissue 4-hydroxyproline content. Solubilized CoQ10 (10 and 30 mg/kg) significantly inhibited both the increases in fibrosis score and 4-hydroxyproline content induced by DMN. Reverse transcription-polymerase chain reaction and Western blot analyses revealed that solubilized CoQ10 inhibited increases in the transforming growth factor-beta1 (TGF-beta1) mRNA and alpha-smooth muscle actin (alpha-SMA) protein by DMN. Interestingly, hepatic glutamate-cysteine ligase (GCL) and glutathione S-transferase A2 (GSTA2) were up-regulated in mice treated with CoQ10. Solubilized CoQ10 also up-regulated antioxidant enzymes such as catalytic subunits of GCL and GSTA2 via activating NF-E2 related factor2 (Nrf2)/antioxidant response element (ARE) in H4IIE hepatoma cells. Moreover, CoQ10's inhibition of alpha-SMA and TGF-beta1 expressions disappeared in Nrf2-null MEF cells. In contrast, Nrf2 overexpression significantly decreased the basal expression levels of alpha-SMA and TGF-beta1 in Nrf2-null MEF cells. These results demonstrated that solubilized CoQ10 inhibited DMN-induced liver fibrosis through suppression of TGF-beta1 expression via Nrf2/ARE activation.

  17. Identification and characterization of transforming growth factor β-activated kinase 1 from Litopenaeus vannamei involved in anti-bacterial host defense.

    PubMed

    Wang, Sheng; Li, Haoyang; L, Kai; Qian, Zhe; Weng, Shaoping; He, Jianguo; Li, Chaozheng

    2016-05-01

    LvTAK1, a member of transforming growth factor β-activated kinase 1 (TAK1) families, has been identified from Litopenaeus vannamei in this study. The full length of LvTAK1 is 2670 bp, including a 2277 bp open reading frame (ORF) that encoded a putative protein of 758 amino acids with a calculated molecular weight of ∼83.4 kDa LvTAK1 expression was most abundant in muscles and was up-regulated in gills after LPS, Vibrio parahaemolyticus, Staphhylococcu saureus, Poly (I:C) and WSSV challenge. Both in vivo and in vitro experiments indicated that LvTAK1 could activate the expression of several antimicrobial peptide genes (AMPs). In addition, the dsRNA-mediated knockdown of LvTAK1 enhanced the susceptibility of shrimps to Vibrio parahaemolyticus, a kind of Gram-negative bacteria. These results suggested LvTAK1 played important roles in anti-bacterial infection. CoIP and subcellular localization assay demonstrated that LvTAK1 could interact with its binding protein LvTAB2, a key component of IMD pathway. Moreover, over-expression of LvTAK1 in Drosophila S2 cell could strongly induce the promoter activity of Diptericin (Dpt), a typical AMP which is used to read out of the activation of IMD pathway. These findings suggested that LvTAK1 could function as a component of IMD pathway. Interestingly, with the over-expression of LvTAK1 in S2 cell, the promoter activity of Metchnikowin (Mtk), a main target gene of Toll/Dif pathway, was up-regulated over 30 times, suggesting that LvTAK1 may also take part in signal transduction of the Toll pathway. In conclusion, we provided some evidences that the involvement of LvTAK1 in the regulation of both Toll and IMD pathways, as well as innate immune against bacterial infection in shrimp. PMID:27033469

  18. Transforming growth factor-beta and transforming growth factor beta-receptor expression in human meningioma cells.

    PubMed Central

    Johnson, M. D.; Federspiel, C. F.; Gold, L. I.; Moses, H. L.

    1992-01-01

    The transforming growth factor-beta (TGF beta) family in mammals includes three closely related peptides that influence proliferation and numerous physiologic processes in most mesenchymal cells. In this study, Northern blots, immunohistochemistry, TGF beta radioreceptor assays, TGF beta receptor affinity labeling and [3H] thymidine incorporation were used to evaluate whether primary cell cultures of human meningiomas synthesize the three TGF beta isoforms, bear TGF beta receptors, and respond to TGF beta. Transcripts for TGF beta 1 and 2 were detected in the three cases analyzed. Transforming growth factor-beta 1 immunoreactivity was detected in three of six cases, and TGF beta 2 and 3 immunoreactivity were detected in each case analyzed. Media conditioned by cells cultured from six meningiomas also contained latent TGF beta-like activity. Transforming growth factor-beta receptor cross-linking studies identified TGF beta binding sites corresponding to the type 1, type 2, and type 3 receptors on meningioma cells. Treatment with active TGF beta 1 produced a statistically significant reduction in [3H] thymidine incorporation after stimulation with 10% fetal calf serum and epidermal growth factor in all six cases studied. Images Figure 1 Figure 2 Figure 4 PMID:1325741

  19. Transforming growth factor-beta stimulates epithelial-mesenchymal transformation in the proepicardium.

    PubMed

    Olivey, Harold E; Mundell, Nathan A; Austin, Anita F; Barnett, Joey V

    2006-01-01

    The proepicardium (PE) migrates over the heart and forms the epicardium. A subset of these PE-derived cells undergoes epithelial-mesenchymal transformation (EMT) and gives rise to cardiac fibroblasts and components of the coronary vasculature. We report that transforming growth factor-beta (TGFbeta) 1 and TGFbeta2 increase EMT in PE explants as measured by invasion into a collagen gel, loss of cytokeratin expression, and redistribution of ZO1. The type I TGFbeta receptors ALK2 and ALK5 are both expressed in the PE. However, only constitutively active (ca) ALK2 stimulates PE-derived epithelial cell activation, the first step in transformation, whereas caALK5 stimulates neither activation nor transformation in PE explants. Overexpression of Smad6, an inhibitor of ALK2 signaling, inhibits epithelial cell activation, whereas BMP7, a known ligand for ALK2, has no effect. These data demonstrate that TGFbeta stimulates transformation in the PE and suggest that ALK2 partially mediates this effect. PMID:16245329

  20. Role of Flightless-I (Drosophila) homolog in the transcription activation of type I collagen gene mediated by transforming growth factor beta

    SciTech Connect

    Lim, Mi-Sun; Jeong, Kwang Won

    2014-11-21

    Highlights: • FLII activates TGFβ-mediated expression of COL1A2 gene. • TGFβ induces the association of FLII with SMAD3 and BRG1 in A549 cells. • FLII is required for the recruitment of SWI/SNF complex and chromatin accessibility to COL1A2 promoter. - Abstract: Flightless-I (Drosophila) homolog (FLII) is a nuclear receptor coactivator that is known to interact with other transcriptional regulators such as the SWI/SNF complex, an ATP-dependent chromatin-remodeling complex, at the promoter or enhancer region of estrogen receptor (ER)-α target genes. However, little is known about the role of FLII during transcription initiation in the transforming growth factor beta (TGFβ)/SMAD-dependent signaling pathway. Here, we demonstrate that FLII functions as a coactivator in the expression of type I collagen gene induced by TGFβ in A549 cells. FLII activates the reporter gene driven by COL1A2 promoter in a dose-dependent manner. Co-expression of GRIP1, CARM1, or p300 did not show any synergistic activation of transcription. Furthermore, the level of COL1A2 expression correlated with the endogenous level of FLII mRNA level. Depletion of FLII resulted in a reduction of TGFβ-induced expression of COL1A2 gene. In contrast, over-expression of FLII caused an increase in the endogenous expression of COL1A2. We also showed that FLII is associated with Brahma-related gene 1 (BRG1) as well as SMAD in A549 cells. Notably, the recruitment of BRG1 to the COL1A2 promoter region was decreased in FLII-depleted A549 cells, suggesting that FLII is required for TGFβ-induced chromatin remodeling, which is carried out by the SWI/SNF complex. Furthermore, formaldehyde-assisted isolation of regulatory elements (FAIRE)-quantitative polymerase chain reaction (qPCR) experiments revealed that depletion of FLII caused a reduction in chromatin accessibility at the COL1A2 promoter. These results suggest that FLII plays a critical role in TGFβ/SMAD-mediated transcription of the COL1A2 gene

  1. Epidermal growth factor signaling in transformed cells

    PubMed Central

    Lindsey, Stephan; Langhans, Sigrid A.

    2016-01-01

    Members of the epidermal growth factor receptor (EGFR/ErbB) family play a critical role in normal cell growth and development. However, many ErbB family members, especially EGFR, are aberrantly expressed or deregulated in tumors and are thought to play crucial roles in cancer development and metastatic progression. In this chapter, we provide an overview of key mechanisms contributing to aberrant EGFR/ErbB signaling in transformed cells which results in many phenotypic changes associated with the earliest stages of tumor formation, including several hallmarks of epithelial-to-mesenchymal transition (EMT). These changes often occur through interaction with other major signaling pathways important to tumor progression resulting in a multitude of transcriptional changes that ultimately impact cell morphology, proliferation and adhesion, all of which are crucial for tumor progression. The resulting mesh of signaling networks will need to be taken into account as new regimens are designed for targeting EGFR for therapeutic intervention. As new insights into the molecular mechanisms of the cross-talk of EGFR signaling with other signaling pathways and their role in therapeutic resistance to anti-EGFR therapies are gained a continual reassessment of clinical therapeutic regimes and strategies will be required. Understanding the consequences and complexity of EGF signaling and how it relates to tumor progression is critical for the development of clinical compounds and establishing clinical protocols for the treatment of cancer. PMID:25619714

  2. Whey protein concentrate enhances intestinal integrity and influences transforming growth factor-β1 and mitogen-activated protein kinase signalling pathways in piglets after lipopolysaccharide challenge.

    PubMed

    Xiao, Kan; Jiao, Lefei; Cao, Shuting; Song, Zehe; Hu, Caihong; Han, Xinyan

    2016-03-28

    Whey protein concentrate (WPC) has been reported to have protective effects on the intestinal barrier. However, the molecular mechanisms involved are not fully elucidated. Transforming growth factor-β1 (TGF-β1) is an important component in the WPC, but whether TGF-β1 plays a role in these processes is not clear. The aim of this study was to investigate the protective effects of WPC on the intestinal epithelial barrier as well as whether TGF-β1 is involved in these protection processes in a piglet model after lipopolysaccharide (LPS) challenge. In total, eighteen weanling pigs were randomly allocated to one of the following three treatment groups: (1) non-challenged control and control diet; (2) LPS-challenged control and control diet; (3) LPS+5 %WPC diet. After 19 d of feeding with control or 5 %WPC diets, pigs were injected with LPS or saline. At 4 h after injection, pigs were killed to harvest jejunal samples. The results showed that WPC improved (P<0·05) intestinal morphology, as indicated by greater villus height and villus height:crypt depth ratio, and intestinal barrier function, which was reflected by increased transepithelial electrical resistance and decreased mucosal-to-serosal paracellular flux of dextran (4 kDa), compared with the LPS group. Moreover, WPC prevented the LPS-induced decrease (P<0·05) in claudin-1, occludin and zonula occludens-1 expressions in the jejunal mucosae. WPC also attenuated intestinal inflammation, indicated by decreased (P<0·05) mRNA expressions of TNF-α, IL-6, IL-8 and IL-1β. Supplementation with WPC also increased (P<0·05) TGF-β1 protein, phosphorylated-Smad2 expression and Smad4 and Smad7 mRNA expressions and decreased (P<0·05) the ratios of the phosphorylated to total c-jun N-terminal kinase (JNK) and p38 (phospho-JNK:JNK and p-p38:p38), whereas it increased (P<0·05) the ratio of extracellular signal-regulated kinase (ERK) (phospho-ERK:ERK). Collectively, these results suggest that dietary inclusion of WPC

  3. Live imaging of transforming growth factor-β activated kinase 1 activation in Lewis lung carcinoma 3LL cells implanted into syngeneic mice and treated with polyinosinic:polycytidylic acid.

    PubMed

    Takaoka, Saori; Kamioka, Yuji; Takakura, Kanako; Baba, Ai; Shime, Hiroaki; Seya, Tsukasa; Matsuda, Michiyuki

    2016-05-01

    Transforming growth factor-β activated kinase 1 (TAK1) has been shown to play a crucial role in cell death, differentiation, and inflammation. Here, we live-imaged robust TAK1 activation in Lewis lung carcinoma 3LL cells implanted into the s.c. tissue of syngeneic C57BL/6 mice and treated with polyinosinic:polycytidylic acid (PolyI:C). First, we developed and characterized a Förster resonance energy transfer-based biosensor for TAK1 activity. The TAK1 biosensor, named Eevee-TAK1, responded to stress-inducing reagents such as anisomycin, tumor necrosis factor-α, and interleukin1-β. The anisomycin-induced increase in Förster resonance energy transfer was abolished by the TAK1 inhibitor (5z)-7-oxozeaenol. Activity of TAK1 in 3LL cells was markedly increased by PolyI:C in the presence of macrophages. 3LL cells expressing Eevee-TAK1 were implanted into mice and observed through imaging window by two-photon excitation microscopy. During the growth of tumor, the 3LL cells at the periphery of the tumor showed higher TAK1 activity than the 3LL cells located at the center of the tumor, suggesting that cells at the periphery of the tumor mass were under stronger stress. Injection of PolyI:C, which is known to induce regression of the implanted tumors, induced marked and homogenous TAK1 activation within the tumor tissues. The effect of PolyI:C faded within 4 days. These observations suggest that Eevee-TAK1 is a versatile tool to monitor cellular stress in cancer tissues. PMID:26931406

  4. Transforming growth factor-beta 1 and fibroblast growth factors in rat growth plate.

    PubMed

    Jingushi, S; Scully, S P; Joyce, M E; Sugioka, Y; Bolander, M E

    1995-09-01

    Chondrocytes in the growth plate progress in an orderly fashion from resting through proliferating to hypertrophic cells. In the region of hypertrophic chondrocytes, the cartilage is invaded by capillary loops and endochondral ossification is initiated. It is currently believed that growth factors may regulate the proliferation and maturation of chondrocytes and the synthesis of extracellular matrix in the growth plate. The ordered sequence of proliferation and differentiation observed in the growth plate provides a unique opportunity to study the role of acidic fibroblast growth factor, basic fibroblast growth factor, and transforming growth factor-beta 1 in the regulation of these processes. In this study, expression of the mRNA of these growth factors was examined using total RNA extracted from the physis and epiphysis of rat tibias. Transforming growth factor-beta 1 mRNA was detected by Northern hybridization. Expression of the genes encoding acidic and basic fibroblast growth factors was demonstrated by polymerase chain reaction amplification. In addition, using polyclonal antibodies against these growth factors, we localized them by immunohistochemical analysis. Strong intracellular staining with a predominantly nuclear pattern was observed in chondrocytes from the proliferating and upper hypertrophic zones. In contrast, chondrocytes in the resting zone stained only faintly for the presence of these growth factors. Some chondrocytes in the resting zone adjacent to the proliferating zone stained with these antibodies, and the antibodies also stained cells in the zone of Ranvier, which regulates latitudinal bone growth. Lastly, the location of transforming growth factor-beta 1 was examined further with use of a polyclonal antipeptide antibody specific for its extracellular epitope.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7472755

  5. Basic science for the clinician 57: transforming growth factor β.

    PubMed

    Sigal, Leonard H

    2012-08-01

    As is so often the case, a molecule gets named for its first identified activity or apparent role and then that initial name sticks, even as new and perhaps fundamentally different activities emerge from later studies. It is the special power of evolution that takes a certain activity and then uses it over and over again in pursuit of apparently disparate goals in a maturing or mature organism. In general terms, transforming growth factor β (TGF-β) is intimately involved in a variety of differentiation and growth inhibition processes, in apoptosis, and in deposition of the extracellular matrix. Initially identified in its role in oncogenesis, TGF-β is now implicated in a number of vascular and rheumatologic disorders, perhaps most notably the scleroderma. TGF-β has been identified as a powerful influence in angiogenesis, wound healing, joint inflammation, tumor growth and metastasis, and, of course, immunoregulation. So "what is in a name?" A rose by any other name would smell as sweet and would still be immunologically active, even if the name is "misleading." PMID:22832292

  6. Mucin1 mediates autocrine transforming growth factor beta signaling through activating the c-Jun N-terminal kinase/activator protein 1 pathway in human hepatocellular carcinoma cells.

    PubMed

    Li, Qiongshu; Liu, Guomu; Shao, Dan; Wang, Juan; Yuan, Hongyan; Chen, Tanxiu; Zhai, Ruiping; Ni, Weihua; Tai, Guixiang

    2015-02-01

    In a previous study, we observed by global gene expression analysis that oncogene mucin1 (MUC1) silencing decreased transforming growth factor beta (TGF-β) signaling in the human hepatocellular carcinoma (HCC) cell line SMMC-7721. In this study, we report that MUC1 overexpression enhanced the levels of phosphorylated Smad3 linker region (p-Smad3L) (Ser-213) and its target gene MMP-9 in HCC cells, suggesting that MUC1 mediates TGF-β signaling. To investigate the effect of MUC1 on TGF-β signaling, we determined TGF-β secretion in MUC1 gene silencing and overexpressing cell lines. MUC1 expression enhanced not only TGF-β1 expression at the mRNA and protein levels but also luciferase activity driven by a TGF-β promoter, as well as elevated the activation of c-Jun N-terminal kinase (JNK) and c-Jun, a member of the activation protein 1 (AP-1) transcription factor family. Furthermore, pharmacological reduction of TGF-β receptor (TβR), JNK and c-Jun activity inhibited MUC1-induced autocrine TGF-β signaling. Moreover, a co-immunoprecipitation assay showed that MUC1 directly bound and activated JNK. In addition, both MUC1-induced TGF-β secretion and exogenous TGF-β1 significantly increased Smad signaling and cell migration, which were markedly inhibited by either TβR inhibitor or small interfering RNA silencing of TGF-β1 gene in HCC cells. The high correlation between MUC1 and TGF-β1 or p-Smad3L (Ser-213) expression was shown in tumor tissues from HCC patients by immunohistochemical staining analysis. Collectively, these results indicate that MUC1 mediates autocrine TGF-β signaling by activating the JNK/AP-1 pathway in HCC cells. Therefore, MUC1 plays a key role in HCC progression and could serve as an attractive target for HCC therapy. PMID:25526895

  7. Cumulin, an Oocyte-secreted Heterodimer of the Transforming Growth Factor-β Family, Is a Potent Activator of Granulosa Cells and Improves Oocyte Quality.

    PubMed

    Mottershead, David G; Sugimura, Satoshi; Al-Musawi, Sara L; Li, Jing-Jie; Richani, Dulama; White, Melissa A; Martin, Georgia A; Trotta, Andrew P; Ritter, Lesley J; Shi, Junyan; Mueller, Thomas D; Harrison, Craig A; Gilchrist, Robert B

    2015-09-25

    Growth differentiation factor 9 (GDF9) and bone morphogenetic protein 15 (BMP15) are oocyte-specific growth factors with central roles in mammalian reproduction, regulating species-specific fecundity, ovarian follicular somatic cell differentiation, and oocyte quality. In the human, GDF9 is produced in a latent form, the mechanism of activation being an open question. Here, we produced a range of recombinant GDF9 and BMP15 variants, examined their in silico and physical interactions and their effects on ovarian granulosa cells (GC) and oocytes. We found that the potent synergistic actions of GDF9 and BMP15 on GC can be attributed to the formation of a heterodimer, which we have termed cumulin. Structural modeling of cumulin revealed a dimerization interface identical to homodimeric GDF9 and BMP15, indicating likely formation of a stable complex. This was confirmed by generation of recombinant heterodimeric complexes of pro/mature domains (pro-cumulin) and covalent mature domains (cumulin). Both pro-cumulin and cumulin exhibited highly potent bioactivity on GC, activating both SMAD2/3 and SMAD1/5/8 signaling pathways and promoting proliferation and expression of a set of genes associated with oocyte-regulated GC differentiation. Cumulin was more potent than pro-cumulin, pro-GDF9, pro-BMP15, or the two combined on GC. However, on cumulus-oocyte complexes, pro-cumulin was more effective than all other growth factors at notably improving oocyte quality as assessed by subsequent day 7 embryo development. Our results support a model of activation for human GDF9 dependent on cumulin formation through heterodimerization with BMP15. Oocyte-secreted cumulin is likely to be a central regulator of fertility in mono-ovular mammals. PMID:26254468

  8. Role of growth factors in the growth of normal and transformed cells

    SciTech Connect

    Lokeshwar, V.B.

    1989-01-01

    Growth factors play an important role in the growth of normal cells. However, their untimely and/or excess production leads to neoplastic transformation. The role of growth factors in the growth of normal cells was studied by investigating the mechanism of transmodulation of the cell surface EGF receptor number by protamine. Protamine increased the EGF stimulated mitogenic response in Swiss mouse 3T3 cells and A431 cells by increasing the number of functionally active EGF receptors. Protamine also increased EGF receptor number in plasma membranes and solubilized membranes. This was evidenced by an increase in both {sup 125}I-EGF-EGF-receptor complex and EGF stimulated phosphorylation of the EGF receptor. The solubilized EGF receptor was retained on a protamine-agarose gel indicating that protamine might increase EGF receptor number by directly activating cryptic EGF receptors in the plasma membranes. The role of growth factors in neoplastic transformation was studied by investigating the role of the oncogene v-sis in the growth of Simian sarcoma virus (SSV) transformed cells. The product of the oncogene v-sis is 94% homologous to the B chain of PDGF. This study found that (i) v-sis gene product is synthesized as a 32 kDa unglycosylated monomer which is glycosylated, dimerized and proteolytically processed into p36, p72, p68, p58, p44 and p27 mol. wt. species respectively. (ii) p36, p72, p68 and p58 are very likely formed in the endoplasmic reticulum and/or Golgi complex. A fraction of newly synthesized p72, p68 and p58 is degraded intracellularly at a fast rate. (iii) p44 is a secretory product which remains tightly associated with the cell surface. p44 is recaptured by the cells through interaction with cell surface PDGF receptors and degraded into p27. (iv) During long term cultures p44 is extracellularly cleaved into a 27 kDa product.

  9. The microbicidal activity of interferon-gamma-treated macrophages against Trypanosoma cruzi involves an L-arginine-dependent, nitrogen oxide-mediated mechanism inhibitable by interleukin-10 and transforming growth factor-beta.

    PubMed

    Gazzinelli, R T; Oswald, I P; Hieny, S; James, S L; Sher, A

    1992-10-01

    The present study was carried out to determine the effector mechanism of anti-Trypanosoma cruzi activity by interferon (IFN)-gamma plus lipopolysaccharide (LPS)-treated macrophages. A macrophage cell line (IC-21) that failed to mount an appreciable oxidative burst was nevertheless found able to control T. cruzi growth after exposure to IFN-gamma alone or IFN-gamma plus LPS. Moreover, microbicidal functions of both inflammatory macrophages and IC-21 against T. cruzi was found to be inhibited in the presence of NG-monomethyl-L-arginine (NGMMA), a competitive inhibitor of L-arginine. Addition of supplemental L-arginine to the culture overcame the capacity of NGMMA to block activated macrophage anti-T. cruzi functions. The ability of NGMMA to reverse both parasite growth inhibition and killing by IFN-gamma plus LPS-activated macrophages was found to correlate with the suppression of nitrite accumulation in the culture supernatants. Together, these results implicate the L-arginine-dependent production of nitric oxide in T. cruzi killing by activated macrophages. We also tested the ability of interleukin(IL)-10 and transforming growth factor (TGF)-beta, to block regulation of T. cruzi growth in this system. Both IL-10 and TGF-beta inhibited anti-parasite function by IFN-gamma-activated macrophages, with an optimal dose of 100 units/ml and 0.5 ng/ml, respectively. Moreover, when used in combination, suboptimal doses of IL-10 and TGF-beta were found to produce a synergistic inhibitory effect in the regulation of T. cruzi growth. The ability of IL-10 and TGF-beta to suppress microbicidal function was also positively correlated with inhibition of nitrite generation in macrophage culture supernatants. These results predict an in vivo role for IL-10 and TGF-beta in promoting parasite survival in the face of the host cell-mediated immune response. PMID:1396957

  10. The latent transforming growth factor beta binding protein (LTBP) family.

    PubMed Central

    Oklü, R; Hesketh, R

    2000-01-01

    The transforming growth factor beta (TGFbeta) cytokines are a multi-functional family that exert a wide variety of effects on both normal and transformed mammalian cells. The secretion and activation of TGFbetas is regulated by their association with latency-associated proteins and latent TGFbeta binding proteins (LTBPs). Over the past few years, three members of the LTBP family have been identified, in addition to the protoype LTBP1 first sequenced in 1990. Three of the LTBP family are expressed in a variety of isoforms as a consequence of alternative splicing. This review summarizes the differences between the isoforms in terms of the effects on domain structure and hence possible function. The close identity between LTBPs and members of the fibrillin family, mutations in which have been linked directly to Marfan's syndrome, suggests that anomalous expression of LTBPs may be associated with disease. Recent data indicating that differential expression of LTBP1 isoforms occurs during the development of coronary heart disease is considered, together with evidence that modulation of LTBP function, and hence of TGFbeta activity, is associated with a variety of cancers. PMID:11104663

  11. Hydrogen peroxide inhibits transforming growth factor-β1-induced cell cycle arrest by promoting Smad3 linker phosphorylation through activation of Akt-ERK1/2-linked signaling pathway.

    PubMed

    Choi, Jiyeon; Park, Seong Ji; Jo, Eun Ji; Lee, Hui-Young; Hong, Suntaek; Kim, Seong-Jin; Kim, Byung-Chul

    2013-06-14

    Hydrogen peroxide (H2O2) functions as a second messenger in growth factor receptor-mediated intracellular signaling cascade and is tumorigenic by virtue of its ability to promote cell proliferation; however, the mechanisms underlying the growth stimulatory action of H2O2 are less understood. Here we report an important mechanism for antagonistic effects of H2O2 on growth inhibitory response to transforming growth factor-β1 (TGF-β1). In Mv1Lu and HepG2 cells, pretreatment of H2O2 (0.05-0.2 mM) completely blocked TGF-β1-mediated induction of p15(INK4B) expression and increase of its promoter activity. Interestingly, H2O2 selectively suppressed the transcriptional activation potential of Smad3, not Smad2, in the absence of effects on TGF-β1-induced phosphorylation of the COOH-tail SSXS motif of Smad3 and its nuclear translocation. Mechanism studies showed that H2O2 increases the phosphorylation of Smad3 at the middle linker region in a concentration- and time-dependent manner and this effect is mediated by activation of extracellular signal-activated kinase 1/2 through Akt. Furthermore, expression of a mutant Smad3 in which linker phosphorylation sites were ablated significantly abrogated the inhibitory effects of H2O2 on TGF-β1-induced increase of p15(INK4B)-Luc reporter activity and blockade of cell cycle progression from G1 to S phase. These findings for the first time define H2O2 as a signaling molecule that modulate Smad3 linker phosphorylation and its transcriptional activity, thus providing a potential mechanism whereby H2O2 antagonizes the cytostatic function of TGF-β1. PMID:23685151

  12. Recruitment of Matrix Metalloproteinase-9 (MMP-9) to the Fibroblast Cell Surface by Lysyl Hydroxylase 3 (LH3) Triggers Transforming Growth Factor-β (TGF-β) Activation and Fibroblast Differentiation*

    PubMed Central

    Dayer, Cynthia; Stamenkovic, Ivan

    2015-01-01

    Solid tumor growth triggers a wound healing response. Similar to wound healing, fibroblasts in the tumor stroma differentiate into myofibroblasts (also referred to as cancer-associated fibroblasts) primarily, but not exclusively, in response to transforming growth factor-β (TGF-β). Myofibroblasts in turn enhance tumor progression by remodeling the stroma. Among proteases implicated in stroma remodeling, matrix metalloproteinases (MMPs), including MMP-9, play a prominent role. Recent evidence indicates that MMP-9 recruitment to the tumor cell surface enhances tumor growth and invasion. In the present work, we addressed the potential relevance of MMP-9 recruitment to and activity at the surface of fibroblasts. We show that recruitment of MMP-9 to the fibroblast cell surface occurs through its fibronectin-like (FN) domain and that the molecule responsible for the recruitment is lysyl hydroxylase 3 (LH3). Functional assays suggest that both pro- and active MMP-9 trigger α-smooth muscle actin expression in cultured fibroblasts, reflecting myofibroblast differentiation, possibly as a result of TGF-β activation. Moreover, the recombinant FN domain inhibited both MMP-9-induced TGF-β activation and α-smooth muscle actin expression by displacing MMP-9 from the fibroblast cell surface. Together our results uncover LH3 as a new docking receptor of MMP-9 on the fibroblast cell surface and demonstrate that the MMP-9 FN domain is essential for the interaction. They also show that the recombinant FN domain inhibits MMP-9-induced TGF-β activation and fibroblast differentiation, providing a potentially attractive therapeutic reagent toward attenuating tumor progression where MMP-9 activity is strongly implicated. PMID:25825495

  13. Hydrogen peroxide inhibits transforming growth factor-β1-induced cell cycle arrest by promoting Smad3 linker phosphorylation through activation of Akt-ERK1/2-linked signaling pathway

    SciTech Connect

    Choi, Jiyeon; Park, Seong Ji; Jo, Eun Ji; Lee, Hui-Young; Hong, Suntaek; Kim, Seong-Jin; Kim, Byung-Chul

    2013-06-14

    Highlights: •H{sub 2}O{sub 2} inhibits TGF-β1-induced cell cycle arrest. •H{sub 2}O{sub 2} induces Smad3 linker phosphorylation through Akt-ERK1/2 pathway. •H{sub 2}O{sub 2}-mediated suppression of TGF-β signal requires Smad3 linker phosphorylation. •This is a first report about interplay between H{sub 2}O{sub 2} and growth inhibition pathway. -- Abstract: Hydrogen peroxide (H{sub 2}O{sub 2}) functions as a second messenger in growth factor receptor-mediated intracellular signaling cascade and is tumorigenic by virtue of its ability to promote cell proliferation; however, the mechanisms underlying the growth stimulatory action of H{sub 2}O{sub 2} are less understood. Here we report an important mechanism for antagonistic effects of H{sub 2}O{sub 2} on growth inhibitory response to transforming growth factor-β1 (TGF-β1). In Mv1Lu and HepG2 cells, pretreatment of H{sub 2}O{sub 2} (0.05–0.2 mM) completely blocked TGF-β1-mediated induction of p15{sup INK4B} expression and increase of its promoter activity. Interestingly, H{sub 2}O{sub 2} selectively suppressed the transcriptional activation potential of Smad3, not Smad2, in the absence of effects on TGF-β1-induced phosphorylation of the COOH-tail SSXS motif of Smad3 and its nuclear translocation. Mechanism studies showed that H{sub 2}O{sub 2} increases the phosphorylation of Smad3 at the middle linker region in a concentration- and time-dependent manner and this effect is mediated by activation of extracellular signal-activated kinase 1/2 through Akt. Furthermore, expression of a mutant Smad3 in which linker phosphorylation sites were ablated significantly abrogated the inhibitory effects of H{sub 2}O{sub 2} on TGF-β1-induced increase of p15{sup INK4B}-Luc reporter activity and blockade of cell cycle progression from G1 to S phase. These findings for the first time define H{sub 2}O{sub 2} as a signaling molecule that modulate Smad3 linker phosphorylation and its transcriptional activity, thus providing

  14. Transforming growth factor-{beta}-inducible phosphorylation of Smad3.

    PubMed

    Wang, Guannan; Matsuura, Isao; He, Dongming; Liu, Fang

    2009-04-10

    Smad proteins transduce the transforming growth factor-beta (TGF-beta) signal at the cell surface into gene regulation in the nucleus. Upon TGF-beta treatment, the highly homologous Smad2 and Smad3 are phosphorylated by the TGF-beta receptor at the SSXS motif in the C-terminal tail. Here we show that in addition to the C-tail, three (S/T)-P sites in the Smad3 linker region, Ser(208), Ser(204), and Thr(179) are phosphorylated in response to TGF-beta. The linker phosphorylation peaks at 1 h after TGF-beta treatment, behind the peak of the C-tail phosphorylation. We provide evidence suggesting that the C-tail phosphorylation by the TGF-beta receptor is necessary for the TGF-beta-induced linker phosphorylation. Although the TGF-beta receptor is necessary for the linker phosphorylation, the receptor itself does not phosphorylate these sites. We further show that ERK is not responsible for TGF-beta-dependent phosphorylation of these three sites. We show that GSK3 accounts for TGF-beta-inducible Ser(204) phosphorylation. Flavopiridol, a pan-CDK inhibitor, abolishes TGF-beta-induced phosphorylation of Thr(179) and Ser(208), suggesting that the CDK family is responsible for phosphorylation of Thr(179) and Ser(208) in response to TGF-beta. Mutation of the linker phosphorylation sites to nonphosphorylatable residues increases the ability of Smad3 to activate a TGF-beta/Smad-target gene as well as the growth-inhibitory function of Smad3. Thus, these observations suggest that TGF-beta-induced phosphorylation of Smad3 linker sites inhibits its antiproliferative activity. PMID:19218245

  15. Partially transformed, anchorage-independent human diploid fibroblasts result from overexpression of the c-sis oncogene: mitogenic activity of an apparent monomeric platelet-derived growth factor 2 species.

    PubMed Central

    Stevens, C W; Brondyk, W H; Burgess, J A; Manoharan, T H; Häne, B G; Fahl, W E

    1988-01-01

    A human c-sis cDNA in an expression vector was introduced into human diploid fibroblasts by transfection or electroporation. Fibroblast clones showing an aberrant, densely packed colony morphology were isolated and found to overexpress a 3.6-kilobase sis mRNA species and associated immunoprecipitable platelet-derived growth factor (PDGF) 2 proteins. Parallel analyses in cell clones of sis mRNA expression and colony formation in agar indicated that, above a threshold, a linear, positive correlation existed between sis overexpression and acquired anchorage independence. The sis-overexpressing cells formed transient, regressing tumor nodules when injected into nude mice, consistent with the finite life span which they retained. Protein products generated from the transfected c-sis construct in two overexpressing clones were immunoprecipitated with anti-human PDGF antibodies. One clone contained an apparent PDGF dimer of 21 kilodaltons; the second clone contained only an apparent PDGF monomer of 12 kilodaltons, which was shown to account for all of the mitogenic activity present in the cells, essentially all of which was concentrated in the membrane fraction. The results demonstrate a clear link between sis overexpression and acquisition of a partially transformed, anchorage-independent phenotype, and when combined with previous observations of sis overexpression in human tumors, clearly implicate sis overexpression as a genetic mechanism which contributes to human cell transformation. Images PMID:3290648

  16. NF-κB-Mediated Modulation of Inducible Nitric Oxide Synthase Activity Controls Induction of the Epstein-Barr Virus Productive Cycle by Transforming Growth Factor Beta 1▿†

    PubMed Central

    Oussaief, Lassad; Ramírez, Vanessa; Hippocrate, Aurélie; Arbach, Hratch; Cochet, Chantal; Proust, Alexis; Raphaël, Martine; Khelifa, Ridha; Joab, Irène

    2011-01-01

    Transforming growth factor beta 1 (TGF-β1) signal transduction has been implicated in many second-messenger pathways, including the NF-κB pathway. We provide evidence of a novel TGF-β1-mediated pathway that leads to extracellular signal-regulated kinase (ERK) 1/2 phosphorylation, which in turn induces expression of an Epstein-Barr virus (EBV) protein, ZEBRA, that is responsible for the induction of the viral lytic cycle. This pathway includes two unexpected steps, both of which are required to control ERK 1/2 phosphorylation: first, a quick and transient activation of NF-κB, and second, downregulation of inducible nitric oxide synthase (iNOS) activity that requires the participation of NF-κB activity. Although necessary, NF-κB alone is not sufficient to produce downregulation of iNOS, suggesting that another uncharacterized event(s) is involved in this pathway. Dissection of the steps involved in the switch from the EBV latent cycle to the lytic cycle will be important to understand how virus-host relationships modulate the innate immune system. PMID:21507981

  17. Transforming growth factor-beta 1 (TGF-beta 1)- and beta 2-like activities in malignant pleural effusions caused by malignant mesothelioma or primary lung cancer.

    PubMed Central

    Maeda, J; Ueki, N; Ohkawa, T; Iwahashi, N; Nakano, T; Hada, T; Higashino, K

    1994-01-01

    We investigated the levels of TGF-beta in malignant pleural effusions (MPE) caused by malignant mesothelioma (MESO) or primary lung cancer. TGF-beta levels in MPE caused by MESO were 283.9 +/- 219.2 pm (mean +/- s.d.) and were three to six times higher than those due to primary lung cancers (P < 0.01 or P < 0.05). We also evaluated TGF-beta 1- and beta 2-like activities in MPE using specific polyclonal antibodies. Although TGF-beta 1-like activity could be detected in all cases, TGF-beta 2-like activities were detected in five of seven in MESO and in a few cases with primary lung cancer. These results demonstrate that the levels of total TGF-beta and TGF-beta 2-like activity may be clinically useful to differentiate MESO from primary lung cancer. Our data also suggest that TGF-beta may help further characterize the clinical features of MESO. PMID:7955539

  18. Linagliptin but not Sitagliptin inhibited transforming growth factor-β2-induced endothelial DPP-4 activity and the endothelial-mesenchymal transition.

    PubMed

    Shi, Sen; Kanasaki, Keizo; Koya, Daisuke

    2016-02-26

    Dipeptidyl peptidase (DPP)-4 plays an important role in endothelial cell biology. We have shown that the DPP-4 inhibitor Linagliptin can inhibit the endothelial-mesenchymal transition (EndMT) and ameliorate diabetic kidney fibrosis associated with the suppression of DPP-4 protein levels via the induction of miR-29. The current study demonstrated that such effects of Linagliptin on endothelial cell profibrotic programs were drug-specific but not class effects. In the cell-free system, both Linagliptin and Sitagliptin inhibited recombinant DPP-4 activity in a concentration-dependent manner. Linagliptin can inhibit all of the following: DPP-4 activity and protein level, integrin β1 protein levels, EndMT, and DPP-4 3'UTR activity; Sitagliptin, however, inhibited none of these in the current study. Additionally, TGF-β2 induced both the induction of VEGF-R1 and the suppression of VEGF-R2 levels in endothelial cells, and both were inhibited by Linagliptin but not by Sitagliptin. miR-29, the miR that negatively regulates the 3'UTR of DPP-4 mRNA, was suppressed by TGF-β2 and restored by Linagliptin but not by Sitagliptin. Following the overexpression of pCMV-DPP-4-GFP and pCMV6-Myc-DPP-4 in endothelial cells, the proximity of Myc-DPP-4 and DPP-4-GFP was suppressed by Linagliptin but not by Sitagliptin, suggesting that only Linagliptin inhibited the homo-dimer formation of DPP-4 in endothelial cells; this difference in activity between the two gliptins could explain their diverse effects on endothelial cell biology. In conclusion, each of the DPP-4 inhibitors may have unique drug-specific effects. PMID:26826382

  19. E6 and E7 oncoproteins from human papillomavirus type 16 induce activation of human transforming growth factor beta1 promoter throughout Sp1 recognition sequence.

    PubMed

    Peralta-Zaragoza, Oscar; Bermúdez-Morales, Víctor; Gutiérrez-Xicotencatl, Lourdes; Alcocer-González, Juan; Recillas-Targa, Félix; Madrid-Marina, Vicente

    2006-01-01

    Human Papillomavirus (HPV) infection is the main etiologic agent of cervical cancer and HPV E6 and E7 oncogenes trans-regulate many cellular genes. An association between TGF-beta1 gene expression and cervical cancer development has been suggested; however, the mechanisms by which HPV influences TGF-beta1 expression remain unclear. In the present study we analyzed the mechanism through which HPV-16 E6 and E7 oncoproteins regulate the TGF-beta1 promoter in cervical tumor cells. Our results showed that E6 and E7 increased TGF-beta1 promoter activity. Furthermore, we identified a specific DNA sequence motif in the TGF-beta1 core promoter that is responsible for trans-activation and that corresponds to the Sp1e-binding site associated with HPV-16 E6 and E7 oncoproteins. Mutational analysis showed that the Sp1e recognition site abolished the trans-activation caused by E6 and E7. These results suggest a physical interaction and functional cooperation between viral oncoproteins and cellular regulatory elements of the TGF-beta1 promoter, and may explain the contribution of HPV-16 to TGF-beta1 gene expression in cervical cancer. PMID:16987065

  20. Micro-computed tomography of pulmonary fibrosis in mice induced by adenoviral gene transfer of biologically active transforming growth factor-β1

    PubMed Central

    2010-01-01

    Background Micro-computed tomography (micro-CT) is a novel tool for monitoring acute and chronic disease states in small laboratory animals. Its value for assessing progressive lung fibrosis in mice has not been reported so far. Here we examined the importance of in vivo micro-CT as non-invasive tool to assess progression of pulmonary fibrosis in mice over time. Methods Pulmonary fibrosis was induced in mice by intratracheal delivery of an adenoviral gene vector encoding biologically active TGF-ß1 (AdTGF-ß1). Respiratory gated and ungated micro-CT scans were performed at 1, 2, 3, and 4 weeks post pulmonary adenoviral gene or control vector delivery, and were then correlated with respective histopathology-based Ashcroft scoring of pulmonary fibrosis in mice. Visual assessment of image quality and consolidation was performed by 3 observers and a semi-automated quantification algorithm was applied to quantify aerated pulmonary volume as an inverse surrogate marker for pulmonary fibrosis. Results We found a significant correlation between classical Ashcroft scoring and micro-CT assessment using both visual assessment and the semi-automated quantification algorithm. Pulmonary fibrosis could be clearly detected in micro-CT, image quality values were higher for respiratory gated exams, although differences were not significant. For assessment of fibrosis no significant difference between respiratory gated and ungated exams was observed. Conclusions Together, we show that micro-CT is a powerful tool to assess pulmonary fibrosis in mice, using both visual assessment and semi-automated quantification algorithms. These data may be important in view of pre-clinical pharmacologic interventions for the treatment of lung fibrosis in small laboratory animals. PMID:21176193

  1. Transforming growth factor-betas and vascular disorders.

    PubMed

    Bobik, Alex

    2006-08-01

    Transforming growth factor-beta (TGF-beta) superfamily members, TGF-beta and bone morphogenetic proteins (BMPs), are potent regulatory cytokines with diverse functions on vascular cells. They signal through heteromeric type I and II receptor complexes activating Smad-dependent and Smad-independent signals, which regulate proliferation, differentiation, and survival. They are potent regulators of vascular development and vessel remodeling and play key roles in atherosclerosis and restenosis, regulating endothelial, smooth muscle cell, macrophage, T cell, and probably vascular calcifying cell responses. In atherosclerosis, TGF-beta regulates lesion phenotype by controlling T-cell responses and stimulating smooth muscle cells to produce collagen. It contributes to restenosis by augmenting neointimal cell proliferation and collagen accumulation. Defective TGF-beta signaling in endothelial cells attributable to mutations in endoglin or the type I receptor ALK-1 leads to hereditary hemorrhagic telangiectasia, whereas defective BMP signaling attributable to mutations in the BMP receptor II has been associated with development of primary pulmonary hypertension. The development of mouse models with either cell type-specific or general inactivation of TGF-beta/BMP signaling has started to reveal the importance of the regulatory network of TGF-beta/BMP pathways in vivo and their significance for atherosclerosis, hereditary hemorrhagic telangiectasia, and primary pulmonary hypertension. This review highlights recent findings that have advanced our understanding of the roles of TGF-beta superfamily members in regulating vascular cell responses and provides likely avenues for future research that may lead to novel pharmacological therapies for the treatment or prevention of vascular disorders. PMID:16675726

  2. Interactions Between β-Catenin and Transforming Growth Factor-β Signaling Pathways Mediate Epithelial-Mesenchymal Transition and Are Dependent on the Transcriptional Co-activator cAMP-response Element-binding Protein (CREB)-binding Protein (CBP)*

    PubMed Central

    Zhou, Beiyun; Liu, Yixin; Kahn, Michael; Ann, David K.; Han, Arum; Wang, Hongjun; Nguyen, Cu; Flodby, Per; Zhong, Qian; Krishnaveni, Manda S.; Liebler, Janice M.; Minoo, Parviz; Crandall, Edward D.; Borok, Zea

    2012-01-01

    Interactions between transforming growth factor-β (TGF-β) and Wnt are crucial to many biological processes, although specific targets, rationale for divergent outcomes (differentiation versus block of epithelial proliferation versus epithelial-mesenchymal transition (EMT)) and precise mechanisms in many cases remain unknown. We investigated β-catenin-dependent and transforming growth factor-β1 (TGF-β1) interactions in pulmonary alveolar epithelial cells (AEC) in the context of EMT and pulmonary fibrosis. We previously demonstrated that ICG-001, a small molecule specific inhibitor of the β-catenin/CBP (but not β-catenin/p300) interaction, ameliorates and reverses pulmonary fibrosis and inhibits TGF-β1-mediated α-smooth muscle actin (α-SMA) and collagen induction in AEC. We now demonstrate that TGF-β1 induces LEF/TCF TOPFLASH reporter activation and nuclear β-catenin accumulation, while LiCl augments TGF-β-induced α-SMA expression, further confirming co-operation between β-catenin- and TGF-β-dependent signaling pathways. Inhibition and knockdown of Smad3, knockdown of β-catenin and overexpression of ICAT abrogated effects of TGF-β1 on α-SMA transcription/expression, indicating a requirement for β-catenin in these Smad3-dependent effects. Following TGF-β treatment, co-immunoprecipitation demonstrated direct interaction between endogenous Smad3 and β-catenin, while chromatin immunoprecipitation (ChIP)-re-ChIP identified spatial and temporal regulation of α-SMA via complex formation among Smad3, β-catenin, and CBP. ICG-001 inhibited α-SMA expression/transcription in response to TGF-β as well as α-SMA promoter occupancy by β-catenin and CBP, demonstrating a previously unknown requisite TGF-β1/β-catenin/CBP-mediated pro-EMT signaling pathway. Clinical relevance was shown by β-catenin/Smad3 co-localization and CBP expression in AEC of IPF patients. These findings suggest a new therapeutic approach to pulmonary fibrosis by specifically

  3. Identification of cellular target genes of the Epstein-Barr virus transactivator Zta: activation of transforming growth factor beta igh3 (TGF-beta igh3) and TGF-beta 1.

    PubMed Central

    Cayrol, C; Flemington, E K

    1995-01-01

    The lytic switch transactivator Zta initiates the ordered cascade of Epstein-Barr virus gene expression that culminates in virus production. Zta is a sequence-specific DNA-binding protein that transactivates early viral promotes via cis-acting sequences. Activation of some of these genes is mediated through binding to consensus AP-1 promoter elements. This observation suggests that Zta may also regulate the expression of cellular genes. While many targets of Zta have been identified in the Epstein-Barr virus genome, putative host cell targets remain largely unknown. To address this issue, a tetracycline-regulated Zta expression system was generated, and differential hybridization screening was used to isolate Zta-responsive cellular genes. The major target identified by this analysis is a gene encoding a fasciclin-like secreted factor, transforming growth factor beta igh3 (TGF-beta igh3), that was originally identified as a gene that is responsive to the potent immunosuppressor TGF-beta 1. Northern (RNA) blot analysis demonstrated that induction of Zta expression results in a 10-fold increase in TGF-beta igh3 mRNA levels. Zta was also found to increase TGF-beta 1 mRNA levels as well as the amount of active TGF-beta 1 secreted into the medium. Interestingly, alpha 1-collagen IV, which has been shown to potentiate the effects of TGF-beta 1, is also a cellular target of Zta. These results suggest that Zta could play a role in modulating the host cell environment through activating the expression of secreted factors. PMID:7769680

  4. Activation of histamine H4 receptors decreases epithelial-to-mesenchymal transition progress by inhibiting transforming growth factor-β1 signalling pathway in non-small cell lung cancer.

    PubMed

    Cai, Wen-Ke; Hu, Jing; Li, Teng; Meng, Jing-Ru; Ma, Xue; Yin, Sun-Jun; Zhao, Can-Hu; He, Gong-Hao; Xu, Gui-Li

    2014-04-01

    Previous investigations found that epithelial-to-mesenchymal transition (EMT) was an important character of non-small cell lung cancer (NSCLC) and it was also suggested that histamine H4 receptors may have a role in preventing EMT progress in certain kind of tumours. However, the effect of H4 receptor activation on EMT progress of NSCLC and its potential mechanisms remain unclear. Therefore, we performed both in vitro and in vivo experiments to explore the effects of specific H4 receptor agonist 4-methylhistamine and antagonist JNJ7777120 on EMT progress. We showed the expression of H4 receptors in NSCLC and found that 4-methylhistamine increased the expression of the epithelial marker E-cadherin and decreased the expression of Vimentin, the mesenchymal marker, in both NSCLC cell lines and xenograft NSCLC tumours. Pretreatment with JNJ7777120 or H4 receptor gene silencing decreased while overexpression of H4 receptors facilitated this effect of 4-methylhistamine. Furthermore, we showed that down-regulation of cyclic adenosine monophosphate (cAMP) was the secondary signalling after H4 receptor activation, which in turn resulted in inactivation of transforming growth factor-β1 (TGF-β1) pathway and down-regulation of several important EMT inducing factors such as ZEB1, Snail and Slug. In conclusion, these findings revealed the anti-EMT effect of histamine H4 receptor activation in NSCLC, which provide novel insight into the development mechanism of NSCLC; and H4 receptors may be a new therapeutic target for NSCLC treatment. PMID:24447834

  5. Nanowire growth by an electron beam induced massive phase transformation

    SciTech Connect

    Sood, Shantanu; Kisslinger, Kim; Gouma, Perena

    2014-11-15

    Tungsten trioxide nanowires of a high aspect ratio have been synthesized in-situ in a TEM under an electron beam of current density 14A/cm² due to a massive polymorphic reaction. Sol-gel processed pseudocubic phase nanocrystals of tungsten trioxide were seen to rapidly transform to one dimensional monoclinic phase configurations, and this reaction was independent of the substrate on which the material was deposited. The mechanism of the self-catalyzed polymorphic transition and accompanying radical shape change is a typical characteristic of metastable to stable phase transformations in nanostructured polymorphic metal oxides. A heuristic model is used to confirm the metastable to stable growth mechanism. The findings are important to the control electron beam deposition of nanowires for functional applications starting from colloidal precursors.

  6. Nanowire growth by an electron beam induced massive phase transformation

    DOE PAGESBeta

    Sood, Shantanu; Kisslinger, Kim; Gouma, Perena

    2014-11-15

    Tungsten trioxide nanowires of a high aspect ratio have been synthesized in-situ in a TEM under an electron beam of current density 14A/cm² due to a massive polymorphic reaction. Sol-gel processed pseudocubic phase nanocrystals of tungsten trioxide were seen to rapidly transform to one dimensional monoclinic phase configurations, and this reaction was independent of the substrate on which the material was deposited. The mechanism of the self-catalyzed polymorphic transition and accompanying radical shape change is a typical characteristic of metastable to stable phase transformations in nanostructured polymorphic metal oxides. A heuristic model is used to confirm the metastable to stablemore » growth mechanism. The findings are important to the control electron beam deposition of nanowires for functional applications starting from colloidal precursors.« less

  7. Activation of Epidermal Growth Factor Receptor/p38/Hypoxia-inducible Factor-1α Is Pivotal for Angiogenesis and Tumorigenesis of Malignantly Transformed Cells Induced by Hexavalent Chromium.

    PubMed

    Kim, Donghern; Dai, Jin; Park, Youn-Hee; Fai, Leonard Yenwong; Wang, Lei; Pratheeshkumar, Poyil; Son, Young-Ok; Kondo, Kazuya; Xu, Mei; Luo, Jia; Shi, Xianglin; Zhang, Zhuo

    2016-07-29

    Hexavalent chromium (Cr(VI))-containing compounds are well established environmental carcinogens. Most mechanistic investigations of Cr(VI)-induced carcinogenesis focus on oxidative stress and various cellular responses, leading to malignant cell transformation or the first stage of metal-induced carcinogenesis. The development of malignantly transformed cells into tumors that require angiogenesis is the second stage. This study focuses on the second stage, in particular, the role of EGF receptor (EGFR) signaling in angiogenesis and tumorigenesis of Cr(VI)-transformed cells. Our preliminary studies have shown that EGFR is constitutively activated in Cr(VI)-transformed cells, in lung tissue from Cr(VI)-exposed animals, and in lung tumor tissue from a non-smoking worker occupationally exposed to Cr(VI) for 19 years. Using in vitro and in vivo models, the present study has investigated the role of EGFR in angiogenesis of Cr(VI)-transformed cells. The results show that Cr(VI)-transformed cells are angiogenic. Hypoxia-inducible factor-1α, pro-angiogenic protein matrix metalloproteinase 1, and VEGF are all highly expressed in Cr(VI)-transformed cells, in lung tissue from animals exposed to Cr(VI), and in lung tumor tissue from a non-smoking worker occupationally exposed to Cr(VI) for 19 years. p38 MAPK is also activated in Cr(VI)-transformed cells and in human lung tumor tissue. Inhibition of EGFR reduces p38 MAPK, resulting in decreased expression of hypoxia-inducible factor-1α, metalloproteinase 1, and VEGF, leading to suppressions of angiogenesis and tumorigenesis. Overall, the present study has demonstrated that EGFR plays an important role in angiogenesis and tumorigenesis of Cr(VI)-transformed cells. PMID:27226640

  8. Immunosuppression in hamsters with progressive visceral leishmaniasis is associated with an impairment of protein kinase C activity in their lymphocytes that can be partially reversed by okadaic acid or anti-transforming growth factor beta antibody.

    PubMed

    Mookerjee, Ananda; Sen, Parimal C; Ghose, Asoke C

    2003-05-01

    Progressive visceral infection of golden hamsters by Leishmania donovani amastigotes led to gradual impairment of the proliferative responses of their splenic or peripheral blood mononuclear cells (SPMC or PBMC, respectively) to in vitro stimulation with phorbol 12-myristate 13-acetate (PMA) and ionomycin (Io). Removal of macrophage-like adherent cells from SPMC or PBMC of infected animals (I-SPMC or I-PBMC) was earlier shown to restore almost completely their lymphoproliferative responses to PMA plus Io. The present study was directed to evaluate the status of protein kinase C (PKC), a molecule(s) known to play a key role in the lymphoproliferative process. Our results demonstrate that PKC activities (Ca(2+), phosphatidyl serine, and diacyl glycerol dependent) in the cytosolic fraction of untreated nonadherent I-SPMC or I-PBMC as well as in the membrane fraction of PMA-treated cells were decreased significantly relative to those for normal controls. However, removal of adherent cells from I-SPMC or I-PBMC and subsequent overnight in vitro cultivation of nonadherent cells (lymphocytes) resulted in significant restoration of PKC activity in the cytosolic or membrane fraction of untreated or PMA-treated cells, respectively. Partial, though significant, restoration of PKC activity could also be achieved in the membrane fraction of PMA-treated cells following overnight in vitro treatment of I-SPMC or I-PBMC with the Ser/Thr phosphatase inhibitor okadaic acid (OA) or an anti-transforming growth factor beta (anti-TGF-beta) neutralizing antibody. These results correlated well with the ability of OA or the anti-TGF-beta antibody to restore the lymphoproliferative response of I-SPMC or I-PBMC following stimulation with PMA plus Io. Interestingly enough, immunoblotting experiments failed to show any reduction in the level or translocation (following PMA treatment) of conventional PKC isoforms in the SPMC or PBMC of infected animals compared to those of normal controls. The

  9. Transforming growth factor (TGF)-. alpha. in human milk

    SciTech Connect

    Okada, Masaki; Wakai, Kae; Shizume, Kazuo ); Iwashita, Mitsutoshi ); Ohmura, Eiji; Kamiya, Yoshinobu; Murakami, Hitomi; Onoda, Noritaka; Tsushima, Toshio

    1991-01-01

    Transforming growth factor (TGF)-{alpha} and epidermal growth factor (EGF) were measured in human milk by means of homologous radioimmunoassay. As previously reported, EGF concentration in the colostrum was approximately 200 ng/ml and decreased to 50 ng/ml by day 7 postpartum. The value of immunoreactive (IR)-TGF-{alpha} was 2.2-7.2 ng/ml, much lower than that of EGF. In contrast to EGF, the concentration of IR-TGF-{alpha} was fairly stable during the 7 postpartum days. There was no relationship between the concentrations of IR-TGF-{alpha} and IR-EGF, suggesting that the regulatory mechanism in the release of the two growth factors is different. On gel-chromatography using a Sephadex G-50 column, IR-EGF appeared in the fraction corresponding to that of authentic human EGF, while 70%-80% of the IR-TGF-{alpha} was eluted as a species with a molecular weight greater than that of authentic human TGF-{alpha}. Although the physiological role of TGF-{alpha} in milk is not known, it is possible that it is involved in the development of the mammary gland and/or the growth of newborn infants.

  10. c-Jun N-terminal kinase 1 promotes transforming growth factor-β1-induced epithelial-to-mesenchymal transition via control of linker phosphorylation and transcriptional activity of Smad3.

    PubMed

    Velden, Jos L J van der; Alcorn, John F; Guala, Amy S; Badura, Elsbeth C H L; Janssen-Heininger, Yvonne M W

    2011-04-01

    Transforming growth factor (TGF)-β1 is a key mediator of lung remodeling and fibrosis. Epithelial cells are both a source of and can respond to TGF-β1 with epithelial-to-mesenchymal transition (EMT). We recently determined that TGF-β1-induced EMT in lung epithelial cells requires the presence of c-Jun N-terminal kinase (JNK) 1. Because TGF-β1 signals via Smad complexes, the goal of the present study was to determine the impact of JNK1 on phosphorylation of Smad3 and Smad3-dependent transcriptional responses in lung epithelial cells. Evaluation of JNK1-deficient lung epithelial cells demonstrated that TGF-β1-induced terminal phosphorylation of Smad3 was similar, whereas phosphorylation of mitogen-activated protein kinase sites in the linker regions of Smad3 was diminished, in JNK1-deficient cells compared with wild-type cells. In comparison to wild-type Smad3, expression of a mutant Smad3 in which linker mitogen-activated protein kinase sites were ablated caused a marked attenuation in JNK1 or TGF-β1-induced Smad-binding element transcriptional activity, and expression of plasminogen activator inhibitor-1, fibronectin-1, high-mobility group A2, CArG box-binding factor-A, and fibroblast-specific protein-1, genes critical in the process of EMT. JNK1 enhanced the interaction between Smad3 and Smad4, which depended on linker phosphorylation of Smad3. Conversely, Smad3 with phosphomimetic mutations in the linker domain further enhanced EMT-related genes and proteins, even in the absence of JNK1. Finally, we demonstrated a TGF-β1-induced interaction between Smad3 and JNK1. Collectively, these results demonstrate that Smad3 phosphorylation in the linker region and Smad transcriptional activity are directly or indirectly controlled by JNK1, and provide a putative mechanism whereby JNK1 promotes TGF-β1-induced EMT. PMID:20581097

  11. [Activated Sludge Bacteria Transforming Cyanopyridines and Amides of Pyridinecarboxylic Acids].

    PubMed

    Demakov, V A; Vasil'ev, D M; Maksimova, Yu G; Pavlova, Yu A; Ovechkina, G V; Maksimov, A Yu

    2015-01-01

    Species diversity of bacteria from the activated sludge of Perm biological waste treatment facilities capable of transformation of cyanopyridines and amides of pyridinecarboxylic acids was investigated. Enrichment cultures in mineral media with 3-cyanopyridine as the sole carbon and nitrogen source were used to obtain 32 clones of gram-negative heterotrophic bacteria exhibiting moderate growth on solid and liquid media with 3- and 4-cyanopyridine. Sequencing of the 16S rRNA gene fragments revealed that the clones with homology of at least 99% belonged to the genera Acinetobacte, Alcaligenes, Delftia, Ochrobactrum, Pseudomonas, Stenotrophomonas, and Xanthobacter. PCR analysis showed that 13 out of 32 isolates contained the sequences (-1070 bp) homologous to the nitrilase genes reported previously in Alcaligenes faecalis JM3 (GenBank, D13419.1). Nine clones were capable of nitrile and amide transformation in minimal salt medium. Acinetobacter sp. 11 h and Alcaligenes sp. osv transformed 3-cyanopyridine to nicotinamide, while most of the clones possessed amidase activity (0.5 to 46.3 mmol/(g h) for acetamide and 0.1 to 5.6 mmol/(g h) for nicotinamide). Nicotinamide utilization by strain A. faecalis 2 was shown to result in excretion of a secondary metabolite, which was identified as dodecyl acrylate at 91% probability. PMID:26263697

  12. Transformation or Transformism: Engestrom's Version of Activity Theory?

    ERIC Educational Resources Information Center

    Avis, James

    2009-01-01

    The paper examines Engestrom's version of activity theory. It seeks to locate this within the socio-economic and theoretical context in which notions of co-configuration and knotworking are set. Although this theoretical approach offers radical possibilities it is limited by its neglect of the wider social context in which activity systems are…

  13. Atomic mechanisms of diffusional nucleation and growth and comparisons with their counterparts in shear transformations

    NASA Astrophysics Data System (ADS)

    Aaronson, Hubert I.

    1993-02-01

    An integrated overview is presented of a viewpoint on the present understanding of nucleation and growth mechanisms in both diffusional and shear (martensitic) transformations. Special emphasis is placed on the roles played by the anisotropy of interphase boundary structure and energy and also upon elastic shear strain energy in both types of transformation. Even though diffusional nucleation is based on random statistical fluctuations, use of the time reversal principle shows that interfacial energy anisotropy leads to accurately reproducible orientation relationships and hence to partially or fully coherent boundaries, even when nucleation at a grain boundary requires an irrational orientation relationship to obtain. Since the fully coherent boundary areas separating most linear misfit compensating defects are wholly immobile during diffusional growth because of the improbability of moving substitutional atoms even temporarily into interstitial sites under conditions normally encountered, partially and fully coherent interphase boundaries should be immovable without the intervention of growth ledges. These ledges, however, must be heavily kinked and usually irregular in both spacing and path if they, too, are not to be similarly trapped. On the other hand, the large shear strain energy usually associated with martensite requires that its formation be initiated through a process which avoids the activation barrier associated with nucleation, perhaps by the Olson-Cohen matrix dislocation rearrangement mechanism. During growth, certain ledges on martensite plates serve as transformation dislocations and perform the crystal structure change (Bain strain). However, the terraces between these ledges in martensite (unlike those present during diffusional growth) are also mobile during non-fcc/hcp transformations; glissile dislocations on these terraces perform the lattice invariant deformation. Growth ledges operative during both diffusional and shear growth probably

  14. Divergent effects of epidermal growth factor and transforming growth factors on a human endometrial carcinoma cell line.

    PubMed

    Korc, M; Haussler, C A; Trookman, N S

    1987-09-15

    Epidermal growth factor (EGF), at concentrations ranging from 0.83 to 4.98 nM, markedly inhibited the proliferation of RL95-2 cells that were seeded at low plating densities (4.7 X 10(3) cells/cm2). Under the same incubation conditions, 16.6 pM EGF enhanced cell proliferation. At high plating densities (2.5 X 10(4) cells/cm2) 0.83 nM EGF also stimulated cell proliferation. Both the inhibitory and stimulatory effects of EGF were mimicked by transforming growth factor-alpha (TGF-alpha). However, the inhibitory action of TGF-alpha was always greater that of EGF. Binding studies with 125I-labeled TGF-alpha indicated that maximal cell surface binding of TGF-alpha occurred at 15 min, whereas maximal internalization occurred at 45 min. Both cell surface and internalized radioactivity declined sharply thereafter. Analysis of radioactivity released into the incubation medium during pulse-chase experiments indicated that RL95-2 cells extensively degraded both TGF-alpha and EGF. The lysosomotropic compound methylamine arrested the generation of low-molecular-weight degradation products of EGF, but not of TGF-alpha. In contrast to EGF and TGF-alpha, transforming growth factor-beta (TGF-beta) inhibited the proliferation of RL95-2 cells that were seeded at either low or high plating densities. Further, transforming growth factor-beta induced the appearance of large cuboidal cells that were readily distinguished from cells treated with either EGF or TGF-alpha. These findings point to complex regulatory actions of growth factors on the proliferation of RL95-2 cells and suggest that the processing of TGF-alpha following EGF receptor activation is distinct from the processing of EGF. PMID:3497713

  15. [THE ROLE OF TRANSFORMING GROWTH FACTOR-B IN IMMUNOPATHOGENESIS OF DISEASES OF CONNECTIVE TISSUE].

    PubMed

    Rudoi, A S; Moskalev, A V; Sboitchakov, V B

    2016-02-01

    The recent studies of molecular physiology of fibrillin and pathophysiology of inherent disorders of structure and function of connective tissue such as dissection and aneurysm of aorta, myxomatously altered cusps and prolapses of mitral valve, syndrome of hyper-mobility of joints, demonstrated that important role in development of these malformations play alterations of transfer of signals by growth factors and matrix cellular interaction. These conditions under manifesting Marfan's syndrome can be a consequence of anomalies of fibrillin-1 which deficiency unbrakes process of activation of transforming growth factor-β (TGFβ). The involvement of TGFβ in pathogenesis of Marfan's syndrome permits consider antagonists of angiotensin-transforming enzymes as potential pharmaceuticals in therapy of this disease. The article presents analysis of publications' data related to this problem. PMID:27455564

  16. Alterations in cellular differentiation, mitogenesis, cytoskeleton and growth characteristics during Syrian hamster embryo cell multistep in vitro transformation.

    PubMed

    Isfort, R J; Cody, D B; Doersen, C J; Kerckaert, G A; Leboeuf, R A

    1994-10-01

    In vitro Syrian hamster embryo (SHE) cell transformation is a neoplastic process that proceeds through several identifiable consecutive stages including in vitro morphological transformation (mt), acquisition of immortality (I+), acquisition of tumorigenicity (T+) and tumor-derived cells (I'TD). Eight transformed lineages consisting of cells at the mt, I+, T+ and I'TD stages were assayed for alterations in general markers of cell differentiation, mitogenic signaling pathways, cytoskeleton and cellular growth in 3D matrix. Alterations in cellular differentiation markers included a decrease in H19 gene expression and placental alkaline phosphatase enzymatic activity at the mt stage in all lineages examined with a complete absence of H19 gene expression and placental alkaline phosphatase enzymatic activity by the I'TD stage in a majority of transformed lineages. Changes in mitogenic signaling pathways included the production of autocrine growth factors and alterations in growth factor-induced immediate early gene expression by the I'TD stage of transformation in the majority of transformed lineages investigated. By the I'TD stage of transformation in most lineages, changes in both the cytoskeleton (including a decrease in tropomyosin-I gene expression) and the Matrigel growth characteristics of SHE cells were observed. PMID:7927892

  17. The Neuroprotective Functions of Transforming Growth Factor Beta Proteins

    PubMed Central

    Dobolyi, Arpád; Vincze, Csilla; Pál, Gabriella; Lovas, Gábor

    2012-01-01

    Transforming growth factor beta (TGF-β) proteins are multifunctional cytokines whose neural functions are increasingly recognized. The machinery of TGF-β signaling, including the serine kinase type transmembrane receptors, is present in the central nervous system. However, the 3 mammalian TGF-β subtypes have distinct distributions in the brain suggesting different neural functions. Evidence of their involvement in the development and plasticity of the nervous system as well as their functions in peripheral organs suggested that they also exhibit neuroprotective functions. Indeed, TGF-β expression is induced following a variety of types of brain tissue injury. The neuroprotective function of TGF-βs is most established following brain ischemia. Damage in experimental animal models of global and focal ischemia was shown to be attenuated by TGF-βs. In addition, support for their neuroprotective actions following trauma, sclerosis multiplex, neurodegenerative diseases, infections, and brain tumors is also accumulating. The review will also describe the potential mechanisms of neuroprotection exerted by TGF-βs including anti-inflammatory, -apoptotic, -excitotoxic actions as well as the promotion of scar formation, angiogenesis, and neuroregeneration. The participation of these mechanisms in the neuroprotective effects of TGF-βs during different brain lesions will also be discussed. PMID:22942700

  18. Modulation of growth and differentiation in normal human keratinocytes by transforming growth factor-beta

    SciTech Connect

    Matsumoto, K.; Hashimoto, K.; Hashiro, M.; Yoshimasa, H.; Yoshikawa, K. )

    1990-10-01

    The effect of transforming growth factor-type beta 1(TGF-beta) on the growth and differentiation of normal human skin keratinocytes cultured in serum-free medium was investigated. TGF-beta markedly inhibited the growth of keratinocytes at the concentrations greater than 2 ng/ml under low Ca2+ conditions (0.1 mM). Growth inhibition was accompanied by changes in cell functions related to proliferation. Remarkable inhibition of DNA synthesis was demonstrated by the decrease of (3H)thymidine incorporation. The decrease of (3H)thymidine incorporation was observed as early as 3 hr after addition of TGF-beta. TGF-beta also decreased c-myc messenger RNA (mRNA) expression 30 min after addition of TGF-beta. This rapid reduction of c-myc mRNA expression by TGF-beta treatment is possibly one of the main factors in the process of TGF-beta-induced growth inhibition of human keratinocytes. Since growth inhibition and induction of differentiation are closely related in human keratinocytes, the growth-inhibitory effect of TGF-beta under high Ca2+ conditions was examined. TGF-beta inhibited the growth of keratinocytes under high Ca2+ conditions in the same manner as under low Ca2+ conditions, suggesting that it is a strong growth inhibitor in both low and high Ca2+ environments. The induction of keratinocyte differentiation was evaluated by measuring involucrin expression and cornified envelope formation: TGF-beta at 20 ng/ml increased involucrin expression from 9.3% to 18.8% under high Ca2+ conditions, while it decreased involucrin expression from 7.0% to 3.3% under low Ca2+ conditions. Cornified envelope formation was modulated in a similar way by addition of TGF-beta: TGF-beta at 20 ng/ml decreased cornified envelope formation by 53% under low Ca2+ conditions, while it enhanced cornified envelope formation by 30.7% under high Ca2+ conditions.

  19. Transforming growth factor beta mRNA increases during liver regeneration: a possible paracrine mechanism of growth regulation.

    PubMed Central

    Braun, L; Mead, J E; Panzica, M; Mikumo, R; Bell, G I; Fausto, N

    1988-01-01

    Transforming growth factor beta (TGF-beta) is a growth factor with multiple biological properties including stimulation and inhibition of cell proliferation. To determine whether TGF-beta is involved in hepatocyte growth responses in vivo, we measured the levels of TGF-beta mRNA in normal liver and during liver regeneration after partial hepatectomy in rats. TGF-beta mRNA increases in the regenerating liver and reaches a peak (about 8 times higher than basal levels) after the major wave of hepatocyte cell division and mitosis have taken place and after the peak expression of the ras protooncogenes. Although hepatocytes from normal and regenerating liver respond to TGF-beta, they do not synthesize TGF-beta mRNA. Instead, the message is present in liver nonparenchymal cells and is particularly abundant in cell fractions enriched for endothelial cells. TGF-beta inhibits epidermal growth factor-induced DNA synthesis in vitro in hepatocytes from normal or regenerating liver, although the dose-response curves vary according to the culture medium used. We conclude that TGF-beta may function as the effector of an inhibitory paracrine loop that is activated during liver regeneration, perhaps to prevent uncontrolled hepatocyte proliferation. Images PMID:3422749

  20. Retinoic acid modulates rat Ito cell proliferation, collagen, and transforming growth factor beta production.

    PubMed Central

    Davis, B H; Kramer, R T; Davidson, N O

    1990-01-01

    Recent studies suggest that vitamin A plays an inhibitory role with respect to "activation" of the hepatic Ito cell, a likely effector of hepatic fibrogenesis. Ito cell "activation" during fibrogenesis is characterized by a decrease in intracellular vitamin A and an increase in cellular proliferation and collagen production. To explore the hypothesis that retinoids have the capacity to diminish Ito cell activation, cultured Ito cells were exposed to retinoic acid and its effects assessed on three key features: cell proliferation, collagen protein production and mRNA abundance, and transforming growth factor beta protein production. Retinoic acid was 100-1,000X more potent than retinol with respect to inhibition of Ito cell proliferation. Interstitial collagen and transforming growth factor beta production were also reduced by 10(-6) M retinoic acid. The relative abundance of type I collagen mRNA however, was not significantly altered. By contrast, retinoic acid administration to rats caused a marked reduction in the abundance of type I collagen mRNA in both total hepatic and purified Ito cell RNA. The relative abundance of rat hepatic fibronectin or apolipoprotein E mRNA was not significantly altered. These studies demonstrate that retinoic acid can differentially modulate several key features of hepatic fibrogenesis in vitro and in vivo. Images PMID:2254460

  1. Toll-Like Receptor 4 Signaling Augments Transforming Growth Factor-β Responses

    PubMed Central

    Bhattacharyya, Swati; Kelley, Kathleen; Melichian, Denisa S.; Tamaki, Zenshiro; Fang, Feng; Su, Yunyun; Feng, Gilbert; Pope, Richard M.; Budinger, G.R. Scott; Mutlu, Gökhan M.; Lafyatis, Robert; Radstake, Timothy; Feghali-Bostwick, Carol; Varga, John

    2014-01-01

    Because recent studies implicate Toll-like receptors (TLRs) in the pathogenesis of fibrosis, we sought to investigate the in vitro and in vivo role and mechanism of TLR4-mediated fibroblast responses in fibrogenesis. We found that TLR4 was constitutively expressed, and accumulation of endogenous TLR4 ligands significantly elevated, in lesional skin and lung tissues from patients with scleroderma. Activation of TLR4 signaling in explanted fibroblasts resulted in enhanced collagen synthesis and increased expression of multiple genes involved in tissue remodeling and extracellular matrix homeostasis. Moreover, TLR4 dramatically enhanced the sensitivity of fibroblasts to the stimulatory effect of transforming growth factor-β1. These profibrotic responses were abrogated by both genetic and pharmacological disruption of TLR4 signaling in vitro, and skin fibrosis induced by bleomycin in vivo was attenuated in mice harboring a mutated TLR4. Activation of TLR4 in fibroblasts augmented the intensity of canonical Smad signaling, and was accompanied by suppression of anti-fibrotic microRNA expression. Together, these results suggest a novel model to account for persistent fibrogenesis in scleroderma, in which activation of fibroblast TLR4 signaling, triggered by damage-associated endogenous TLR4 ligands, results in augmented transforming growth factor-β1 sensitivity with increased matrix production and progressive connective tissue remodeling. Under these conditions, fibroblast TLR4 serves as the switch for converting self-limited tissue repair into intractable fibrosis. PMID:23141927

  2. Autocrine and exogenous transforming growth factor beta control cell cycle inhibition through pathways with different sensitivity.

    PubMed

    Wang, Jing; Sergina, Natalia; Ko, Tien C; Gong, Jiangeng; Brattain, Michael G

    2004-09-17

    Human colon carcinoma cells HCT116 that lack transforming growth factor beta (TGF-beta) type II receptor (RII) demonstrated restoration of autocrine TGF-beta activity upon reexpression of RII without restoring inhibitory responses to exogenous TGF-beta treatment. RII transfectants (designated RII Cl 37) had a longer lag phase relative to NEO-transfected control cells (designated NEO pool) before entering exponential growth in tissue culture. The prolonged growth arrest of RII Cl 37 cells was associated with markedly reduced cyclin-dependent kinase (CDK)2 activity. Our results demonstrate that p21 induction by autocrine TGF-beta is responsible for reduced CDK2 activity, which at least partially contributes to prolonged growth arrest and reduced cell proliferation in RII Cl 37 cells. In contrast to RII transfectants, HCT116 cells transfected with chromosome 3 (designated HCT116Ch3), which bears the RII gene, restored the response to exogenous TGF-beta as well as autocrine TGF-beta activity. Autocrine TGF-beta activity in HCT116Ch3 cells induced p21 expression as seen in RII Cl 37 cells; however, in addition to autocrine activity, HCT116Ch3 cells responded to exogenous TGF-beta as decreased CDK4 expression and reduced pRb phosphorylation mediated a TGF-beta inhibitory response in these cells. These results indicate that autocrine TGF-beta regulates the cell cycle through a pathway different from exogenous TGF-beta in the sense that p21 is a more sensitive effector of the TGF-beta signaling pathway, which can be induced and saturated by autocrine TGF-beta, whereas CDK4 inhibition is a less sensitive effector, which can only be activated by high levels of exogenous TGF-beta PMID:15271980

  3. Creating Activating Events for Transformative Learning in a Prison Classroom

    ERIC Educational Resources Information Center

    Keen, Cheryl H.; Woods, Robert

    2016-01-01

    In this article, we interpreted, in light of Mezirow's theory of transformative learning, interviews with 13 educators regarding their work with marginalized adult learners in prisons in the northeastern United States. Transformative learning may have been aided by the educators' response to unplanned activating events, humor, and respect, and…

  4. [Transforming growth factor beta-1: structure, function, and regulation mechanisms in cancer].

    PubMed

    Peralta-Zaragoza, O; Lagunas-Martínez, A; Madrid-Marina, V

    2001-01-01

    Transforming growth factor beta-1 (TGF-beta 1) is produced by several cell lineages such as lymphocytes, macrophages, and dendritic cells, and its expression serves in both autocrine and paracrine modes to control the differentiation, proliferation, and state of activation of these and other cells. In general, TGF-beta 1 has pleiotropic properties on the immune response during the development of infection diseases and cancer; however, the mechanisms of action and regulation of gene expression of this cytokine are poorly understood, in this review, the biological properties and the molecular mechanisms that regulate TGF-beta 1 gene expression are described, to understand the role of this cytokine in growth and cell differentiation. The knowledge of molecular mechanisms of gene expression of TGF-beta 1 may serve to develop new cancer therapies. The English version of this paper is available at: http://www.insp.mx/salud/index.html PMID:11547595

  5. Transforming growth factor alpha and epidermal growth factor levels in bladder cancer and their relationship to epidermal growth factor receptor.

    PubMed Central

    Mellon, J. K.; Cook, S.; Chambers, P.; Neal, D. E.

    1996-01-01

    We have examined levels of epidermal growth factor (EGF) and transforming growth factor alpha (TGF-alpha) in neoplastic and non-neoplastic bladder tissue using a standard radioimmunoassay technique. Tumour samples had much higher TGF-alpha levels compared with EGF and TGF-alpha levels in malignant tissue were significantly higher than in benign bladder samples. There was, in addition, a difference in mean EGF levels from 'normal' bladder samples from non-tumour bearing areas of bladder in patients with bladder cancer compared with 'normal' bladder tissue obtained at the time of organ retrieval surgery. Levels of EGF and TGF-alpha did not correlate with levels of EGF receptor (EGFR) as determined by a radioligand binding method but levels of TGF-alpha > 10 ng gm-1 of tumour tissue did correlate with EGFR positivity defined using immunohistochemistry. These data suggest that TGF-alpha is the likely ligand for EGFR in bladder tumours. PMID:8605103

  6. Transforming your professional self: encouraging lifelong personal and professional growth.

    PubMed

    Rodts, Mary F; Lamb, Karen V

    2008-01-01

    Transforming from student nurse to registered nurse is often discussed in a capstone class or a hospital orientation program. Changes in professional plans later in the career continuum often occur, but are not always planned. This article discusses the challenges of change, the need for career planning, stages of role acquisition, role socialization, and role transformation. In addition, it outlines the importance of creating a career plan to meet future career goals. PMID:18385597

  7. TERATOGENIC RESPONSES ARE MODULATED IN MICE LACKING EXPRESSION OF EPIDERMAL GROWTH FACTOR (EGF) AND TRANSFORMING GROWTH FACTOR-ALPHA (TGF)

    EPA Science Inventory

    TITLE:
    TERATOGENIC RESPONSES ARE MODULATED IN MICE LACKING EXPRESSION OF EPIDERMAL GROWTH FACTOR (EGF) AND TRANSFORMING GROWTH FACTOR-ALPHA (TGF). AUTHORS (ALL): Abbott, Barbara D.1; Best, Deborah S.1; Narotsky, Michael G.1. SPONSOR NAME: None INSTITUTIONS (ALL): 1. Repro Tox ...

  8. Transforming Staff Practice through Active Support

    ERIC Educational Resources Information Center

    Riches, Vivienne C.; Harman, Anthony D.; Keen, Deb; Pennell, Donna; Harley, Jane H.; Walker, Michelle

    2011-01-01

    Background: Active support is being introduced in many residential and respite homes in an effort to improve engagement in meaningful activity of people with intellectual disability. Method: A train-the-trainer approach was used in a large government organisation that supports people with intellectual disability in Australia. Five apprentice…

  9. Hammerhead Ribozyme-Mediated Knockdown of mRNA for Fibrotic Growth Factors: Transforming Growth Factor-Beta 1 and Connective Tissue Growth Factor

    PubMed Central

    Robinson, Paulette M.; Blalock, Timothy D.; Yuan, Rong; Lewin, Alfred S.; Schultz, Gregory S.

    2013-01-01

    Excessive scarring (fibrosis) is a major cause of pathologies in multiple tissues, including lung, liver, kidney, heart, cornea, and skin. The transforming growth factor- β (TGF- β) system has been shown to play a key role in regulating the formation of scar tissue throughout the body. Furthermore, connective tissue growth factor (CTGF) has been shown to mediate most of the fibrotic actions of TGF- β, including stimulation of synthesis of extracellular matrix and differentiation of fibroblasts into myofibroblasts. Currently, no approved drugs selectively and specifically regulate scar formation. Thus, there is a need for a drug that selectively targets the TGF- β cascade at the molecular level and has minimal off-target side effects. This chapter focuses on the design of hammerhead ribozymes, measurement of kinetic activity, and assessment of knockdown mRNAs of TGF- β and CTGF in cell cultures. PMID:22131029

  10. Serum deprivation response inhibits breast cancer progression by blocking transforming growth factor-β signaling.

    PubMed

    Tian, Yao; Yu, Yue; Hou, Li-Kun; Chi, Jiang-Rui; Mao, Jie-Fei; Xia, Li; Wang, Xin; Wang, Ping; Cao, Xu-Chen

    2016-03-01

    Serum deprivation response (SDPR), a key substrate for protein kinase C, play a critical role in inducing membrane curvature and participate in the formation of caveolae. However, the function of SDPR in cancer development and progression is still not clear. Here, we found that SDPR is downregulated in human breast cancer. Overexpression of SDPR suppresses cell proliferation and invasion in MDA-MB-231 cells, while depletion of SDPR promotes cell proliferation and invasion in MCF10A cells. Subsequently, SDPR depletion induces epithelial-mesenchymal transition (EMT)-like phenotype. Finally, knockdown of SDPR activates transforming growth factor-β (TGF-β) signaling by upregulation of TGF-β1 expression. In conclusion, our results showed that SDPR inhibits breast cancer progression by blocking TGF-β signaling. Serum deprivation response suppresses cell proliferation and invasion in breast cancer cells. SDPR depletion induces epithelial-mesenchymal transition by activation of TGF-β signaling. PMID:26749136

  11. Transforming growth factor-beta1 mediates cellular response to DNA damage in situ

    NASA Technical Reports Server (NTRS)

    Ewan, Kenneth B.; Henshall-Powell, Rhonda L.; Ravani, Shraddha A.; Pajares, Maria Jose; Arteaga, Carlos; Warters, Ray; Akhurst, Rosemary J.; Barcellos-Hoff, Mary Helen

    2002-01-01

    Transforming growth factor (TGF)-beta1 is rapidly activated after ionizing radiation, but its specific role in cellular responses to DNA damage is not known. Here we use Tgfbeta1 knockout mice to show that radiation-induced apoptotic response is TGF-beta1 dependent in the mammary epithelium, and that both apoptosis and inhibition of proliferation in response to DNA damage decrease as a function of TGF-beta1 gene dose in embryonic epithelial tissues. Because apoptosis in these tissues has been shown previously to be p53 dependent, we then examined p53 protein activation. TGF-beta1 depletion, by either gene knockout or by using TGF-beta neutralizing antibodies, resulted in decreased p53 Ser-18 phosphorylation in irradiated mammary gland. These data indicate that TGF-beta1 is essential for rapid p53-mediated cellular responses that mediate cell fate decisions in situ.

  12. Enhanced jun gene expression is an early genomic response to transforming growth factor beta stimulation.

    PubMed Central

    Pertovaara, L; Sistonen, L; Bos, T J; Vogt, P K; Keski-Oja, J; Alitalo, K

    1989-01-01

    Transforming growth factor beta (TGF beta) is a multifunctional polypeptide that regulates proliferation, differentiation, and other functions of many cell types. The pathway of TGF beta signal transduction in cells is unknown. We report here that an early effect of TGF beta is an enhancement of the expression of two genes encoding serum- and phorbol ester tumor promoter-regulated transcription factors: the junB gene and the c-jun proto-oncogene, respectively. This stimulation was observed in human lung adenocarcinoma A549 cells which were growth inhibited by TGF beta, AKR-2B mouse embryo fibroblasts which were growth stimulated by TGF beta, and K562 human erythroleukemia cells, which were not appreciably affected in their growth by TGF beta. The increase in jun mRNA occurred with picomolar TGF beta concentrations within 1 h of TGF beta stimulation, reached a peak between 1 and 5 h in different cells, and declined gradually to base-line levels. This mRNA response was followed by a large increase in the biosynthesis of the c-jun protein (AP-1), as shown by metabolic labeling and immunoprecipitation analysis. However, differential and cell type-specific regulation appeared to determine the timing and magnitude of the response of each jun gene in a given cell. In AKR-2B and NIH 3T3 cells, only junB was induced by TGF beta, evidently in a protein synthesis-independent fashion. The junB response to TGF beta was maintained in c-Ha-ras and neu oncogene-transformed cells. Thus, one of the earliest genomic responses to TGF beta may involve nuclear signal transduction and amplification by the junB and c-jun transcription factors in concert with c-fos, which is also induced. The differential activation of the jun genes may explain some of the pleiotropic effects of TGF beta. Images PMID:2725496

  13. Transforming Asian Pacific America: The Challenges of Growth and Diversity.

    ERIC Educational Resources Information Center

    Nakanishi, Don T.

    1994-01-01

    Examines the concept of Asian Pacific pan-ethnicity in light of the growing numbers and diversity of this population in the 1990s. While revised immigration laws, new immigrant groups, and continued hostility have brought new challenges, it is argued that Asian Pacific Americans can provide important leadership for the transformation of the United…

  14. Mutant forms of growth factor-binding protein-2 reverse BCR-ABL-induced transformation.

    PubMed Central

    Gishizky, M L; Cortez, D; Pendergast, A M

    1995-01-01

    Growth factor-binding protein 2 (Grb2) is an adaptor protein that links tyrosine kinases to Ras. BCR-ABL is a tyrosine kinase oncoprotein that is implicated in the pathogenesis of Philadelphia chromosome (Ph1)-positive leukemias. Grb2 forms a complex with BCR-ABL and the nucleotide exchange factor Sos that leads to the activation of the Ras protooncogene. In this report we demonstrate that Grb2 mutant proteins lacking amino- or carboxyl-terminal src homology SH3 domains suppress BCR-ABL-induced Ras activation and reverse the oncogenic phenotype. The Grb2 SH3-deletion mutant proteins bind to BCR-ABL and do not impair tyrosine kinase activity. Expression of the Grb2 SH3-deletion mutant proteins in BCR-ABL-transformed Rat-1 fibroblasts and in the human Ph1-positive leukemic cell line K562 inhibits their ability to grow as foci in soft agar and form tumors in nude mice. Furthermore, expression of the Grb2 SH3-deletion mutants in K562 cells induced their differentiation. Because Ras plays an important role in signaling by receptor and nonreceptor tyrosine kinases, the use of interfering mutant Grb2 proteins may be applied to block the proliferation of other cancers that depend in part on activated tyrosine kinases for growth. Images Fig. 1 Fig. 2 Fig. 3 PMID:7479904

  15. Transforming growth factor-beta as a differentiating factor for cultured smooth muscle cells.

    PubMed

    Gawaziuk, J P; X; Sheikh, F; Cheng, Z-Q; Cattini, P A; Stephens, N L

    2007-10-01

    The aim of the present study was to determine whether the development of supercontractile smooth muscle cells, contributing to the nonspecific hyperreactivity of airways in asthmatic patients, is due to transforming growth factor (TGF)-beta. In cultured smooth muscle cells starved by removal of 10% foetal bovine serum for 7 days, growth arrest was seen; 30% became elongated and demonstrated super contractility. Study of conditioned medium suggested that the differentiating factor was TGF-beta. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) was carried out on conditioned medium from the arrested cells. Two protein bands were identified as matrix metalloproteinase (MMP)-2 and TGF-beta1. To determine second messenger signalling by SMAD2, Western blotting and confocal microscopy were employed. Conditioned medium from arrested cultures showed the presence of MMP-2 and TGF-beta1, as revealed by SDS-PAGE; 68- and 25-kDa bands were seen. Differentiation was confirmed by upregulation of marker proteins, smooth muscle type myosin heavy chain and myosin light chain kinase. Confirmation was obtained by downregulating these proteins with decorin treatment, which reduces the levels of active TGF-beta and an adenoviral dominant-negative vector coding for a mutated type II TGF-beta-receptor. Activation of second messenger signalling was demonstrated immunocytochemically by the presence of phosphorylated SMAD2 and SMAD4. Transforming growth factor-beta is likely to be the differentiating factor responsible for the development of these supercontractile smooth muscle cells. The development of such cells in vivo after cessation of an asthmatic attack could contribute to the nonspecific hyperreactivity of airways seen in patients. PMID:17596270

  16. Capsaicin Inhibits Preferentially the NADH Oxidase and Growth of Transformed Cells in Culture

    NASA Astrophysics Data System (ADS)

    Morre, D. James; Chueh, Pin-Ju; Morre, Dorothy M.

    1995-03-01

    A hormone- and growth factor-stimulated NADH oxidase of the mammalian plasma membrane, constitutively activated in transformed cells, was inhibited preferentially in HeLa, ovarian carcinoma, mammary adenocarcinoma, and HL-60 cells, all of human origin, by the naturally occurring quinone analog capsaicin (8-methyl-N-vanillyl-6-noneamide), compared with plasma membranes from human mammary epithelial, rat liver, normal rat kidney cells, or HL-60 cells induced to differentiate with dimethyl sulfoxide. With cells in culture, capsaicin preferentially inhibited growth of HeLa, ovarian carcinoma, mammary adenocarcinoma, and HL-60 cells but was largely without effect on the mammary epithelial cells, rat kidney cells, or HL-60 cells induced to differentiate with dimethyl sulfoxide. Inhibited cells became smaller and cell death was accompanied by a condensed and fragmented appearance of the nuclear DNA, as revealed by fluorescence microscopy with 4',6-diamidino-2-phenylindole, suggestive of apoptosis. The findings correlate capsaicin inhibition of cell surface NADH oxidase activity and inhibition of growth that correlate with capsaicin-induced apoptosis.

  17. Transforming Teacher Education, An Activity Theory Analysis

    ERIC Educational Resources Information Center

    McNicholl, Jane; Blake, Allan

    2013-01-01

    This paper explores the work of teacher education in England and Scotland. It seeks to locate this work within conflicting sociocultural views of professional practice and academic work. Drawing on an activity theory framework that integrates the analysis of these seemingly contradictory discourses with a study of teacher educators' practical…

  18. eps15, a novel tyrosine kinase substrate, exhibits transforming activity.

    PubMed Central

    Fazioli, F; Minichiello, L; Matoskova, B; Wong, W T; Di Fiore, P P

    1993-01-01

    An expression cloning method which allows direct isolation of cDNAs encoding substrates for tyrosine kinases was applied to the study of the epidermal growth factor (EGF) receptor (EGFR) signaling pathway. A previously undescribed cDNA was isolated and designated eps15. The structural features of the predicted eps15 gene product allow its subdivision into three domains. Domain I contains signatures of a regulatory domain, including a candidate tyrosine phosphorylation site and EF-hand-type calcium-binding domains. Domain II presents the characteristic heptad repeats of coiled-coil rod-like proteins, and domain III displays a repeated aspartic acid-proline-phenylalanine motif similar to a consensus sequence of several methylases. Antibodies specific for the eps15 gene product recognize two proteins: a major species of 142 kDa and a minor component of 155 kDa, both of which are phosphorylated on tyrosine following EGFR activation by EGF in vivo. EGFR is also able to directly phosphorylate the eps15 product in vitro. In addition, phosphorylation of the eps15 gene product in vivo is relatively receptor specific, since the erbB-2 kinase phosphorylates it very inefficiently. Finally, overexpression of eps15 is sufficient to transform NIH 3T3 cells, thus suggesting that the eps15 gene product is involved in the regulation of mitogenic signals. Images PMID:7689153

  19. Harnessing high density lipoproteins to block transforming growth factor beta and to inhibit the growth of liver tumor metastases.

    PubMed

    Medina-Echeverz, José; Fioravanti, Jessica; Díaz-Valdés, Nancy; Frank, Kathrin; Aranda, Fernando; Gomar, Celia; Ardaiz, Nuria; Dotor, Javier; Umansky, Viktor; Prieto, Jesús; Berraondo, Pedro

    2014-01-01

    Transforming growth factor β (TGF-β) is a powerful promoter of cancer progression and a key target for antitumor therapy. As cancer cells exhibit active cholesterol metabolism, high density lipoproteins (HDLs) appear as an attractive delivery system for anticancer TGFβ-inhibitory molecules. We constructed a plasmid encoding a potent TGF-β-blocking peptide (P144) linked to apolipoprotein A-I (ApoA-I) through a flexible linker (pApoLinkerP144). The ApoLinkerP144 sequence was then incorporated into a hepatotropic adeno-associated vector (AAVApoLinkerP144). The aim was to induce hepatocytes to produce HDLs containing a modified ApoA-I capable of blocking TGF-β. We observed that transduction of the murine liver with pApoLinkerP144 led to the appearance of a fraction of circulating HDL containing the fusion protein. These HDLs were able to attenuate TGF-β signaling in the liver and to enhance IL-12 -mediated IFN-γ production. Treatment of liver metastasis of MC38 colorectal cancer with AAVApoLinkerP144 resulted in a significant reduction of tumor growth and enhanced expression of IFN-γ and GM-CSF in cancerous tissue. ApoLinkerP144 also delayed MC38 liver metastasis in Rag2-/-IL2rγ-/- immunodeficient mice. This effect was associated with downregulation of TGF-β target genes essential for metastatic niche conditioning. Finally, in a subset of ret transgenic mice, a model of aggressive spontaneous metastatic melanoma, AAVApoLinkerP144 delayed tumor growth in association with increased CD8+ T cell numbers in regional lymph nodes. In conclusion, modification of HDLs to transport TGF-β-blocking molecules is a novel and promising approach to inhibit the growth of liver metastases by immunological and non-immunological mechanisms. PMID:24797128

  20. Harnessing High Density Lipoproteins to Block Transforming Growth Factor Beta and to Inhibit the Growth of Liver Tumor Metastases

    PubMed Central

    Medina-Echeverz, José; Fioravanti, Jessica; Díaz-Valdés, Nancy; Frank, Kathrin; Aranda, Fernando; Gomar, Celia; Ardaiz, Nuria; Dotor, Javier; Umansky, Viktor; Prieto, Jesús; Berraondo, Pedro

    2014-01-01

    Transforming growth factor β (TGF-β) is a powerful promoter of cancer progression and a key target for antitumor therapy. As cancer cells exhibit active cholesterol metabolism, high density lipoproteins (HDLs) appear as an attractive delivery system for anticancer TGFβ-inhibitory molecules. We constructed a plasmid encoding a potent TGF-β-blocking peptide (P144) linked to apolipoprotein A-I (ApoA-I) through a flexible linker (pApoLinkerP144). The ApoLinkerP144 sequence was then incorporated into a hepatotropic adeno-associated vector (AAVApoLinkerP144). The aim was to induce hepatocytes to produce HDLs containing a modified ApoA-I capable of blocking TGF-β. We observed that transduction of the murine liver with pApoLinkerP144 led to the appearance of a fraction of circulating HDL containing the fusion protein. These HDLs were able to attenuate TGF-β signaling in the liver and to enhance IL-12 -mediated IFN-γ production. Treatment of liver metastasis of MC38 colorectal cancer with AAVApoLinkerP144 resulted in a significant reduction of tumor growth and enhanced expression of IFN-γ and GM-CSF in cancerous tissue. ApoLinkerP144 also delayed MC38 liver metastasis in Rag2−/−IL2rγ−/− immunodeficient mice. This effect was associated with downregulation of TGF-β target genes essential for metastatic niche conditioning. Finally, in a subset of ret transgenic mice, a model of aggressive spontaneous metastatic melanoma, AAVApoLinkerP144 delayed tumor growth in association with increased CD8+ T cell numbers in regional lymph nodes. In conclusion, modification of HDLs to transport TGF-β-blocking molecules is a novel and promising approach to inhibit the growth of liver metastases by immunological and non-immunological mechanisms. PMID:24797128

  1. ATP differentially upregulates fibroblast growth factor 2 and transforming growth factor α in neonatal and adult mice: effect on neuroproliferation.

    PubMed

    Jia, C; Cussen, A R; Hegg, C C

    2011-03-17

    Multiple neurotrophic factors play a role in proliferation, differentiation and survival in the olfactory epithelium (OE); however, the signaling cascade has not been fully elucidated. We tested the hypotheses that ATP induces the synthesis and secretion of two neurotrophic factors, fibroblast growth factor 2 (FGF2) and transforming growth factor alpha (TGFα), and that these neurotrophic factors have a role in inducing proliferation. Protein levels of FGF2 and TGFα were increased 20 h post-intranasal instillation of ATP compared to vehicle control in adult Swiss Webster mice. Pre-intranasal treatment with purinergic receptor antagonist pyridoxal-phosphate-6-azophenyl-20,40-disulfonic acid (PPADS) significantly blocked this ATP-induced increase, indicating that upregulation of FGF2 and TGFα expression is mediated by purinergic receptor activation. However, in neonatal mouse, intranasal instillation of ATP significantly increased the protein levels of FGF2, but not TGFα. Likewise, ATP evoked the secretion of FGF2, but not TGFα, from neonatal mouse olfactory epithelial slices and PPADS significantly blocked ATP-evoked FGF2 release. To determine the role of FGF2 and TGFα in inducing proliferation, 5-bromo-2-deoxyuridine (BrdU) incorporation was examined in adult olfactory epithelium. Intranasal treatment with FGF receptor inhibitor PD173074 or epidermal growth factor receptor inhibitor AG1478 following ATP instillation significantly blocked ATP-induced BrdU incorporation. Collectively, these data demonstrate that ATP induces proliferation in adult mouse olfactory epithelium by promoting FGF2 and TGFα synthesis and activation of their receptors. These data suggest that different mechanisms regulate neurogenesis in neonatal and adult OE, and FGF2 and TGFα may have different roles throughout development. PMID:21187124

  2. Nuclear translocation of type I transforming growth factor β receptor confers a novel function in RNA processing.

    PubMed

    Chandra, Manasa; Zang, Shengbing; Li, Haiqing; Zimmerman, Lisa J; Champer, Jackson; Tsuyada, Akihiro; Chow, Amy; Zhou, Weiying; Yu, Yang; Gao, Harry; Ren, Xiubao; Lin, Ren-Jang; Wang, Shizhen Emily

    2012-06-01

    Signaling of transforming growth factor β (TGF-β) is redirected in cancer to promote malignancy, but how TGF-β function is altered in a transformed cell is not fully understood. We investigated TGF-β signaling by profiling proteins that differentially bound to type I TGF-β receptor (TβRI) in nontransformed, HER2-transformed, and HER2-negative breast cancer cells using immunoprecipitation followed by protein identification. Interestingly, several nuclear proteins implicated in posttranscriptional RNA processing were uniquely identified in the TβRI coprecipitates from HER2-transformed cells. Ligand-inducible nuclear translocation of TβRI was observed only in transformed cells, and the translocation required importin β1, nucleolin, and Smad2/3. This trafficking was dependent on the high Ran GTPase activity resulting from oncogenic transformation. In the nucleus, TβRI associated with purine-rich RNA sequences in a synergistic manner with the RNA-binding factor hnRNP A1. We further found that nuclear translocation of TβRI specifically induced epidermal growth factor receptor (EGFR) transcript isoform c, which encodes a soluble EGFR protein, through alternative splicing or 3'-end processing. Our study confirms a cancer-specific nuclear translocation of TβRI and demonstrates its potential function in regulating nuclear RNA processing, as well as a novel gain-of-function mechanism of TGF-β signaling in cancer. PMID:22473997

  3. [Cytogenetic activity of the butylcaptax defoliant transformation product].

    PubMed

    Vesmanova, O Ia; Semykina, E E; Koblov, R K; Ergashev

    1989-01-01

    Cytogenetical activity of the product of metabolitic butylcaptax transformations in cells of cotton plants G. barbadense has been studied. It is shown that butylcaptax, with a significant mutagenicity, looses its mutagenic activity, metabolizing in low mutagenic 2-oxyamylthiobenzthiazole. Low water solubility prevents its concentration to exceed 0.005% in tissue liquids and to exert a mutagenic action on cotton plants. PMID:2773061

  4. Abrogation of fibroblast activation protein enzymatic activity attenuates tumor growth.

    PubMed

    Cheng, Jonathan D; Valianou, Matthildi; Canutescu, Adrian A; Jaffe, Eileen K; Lee, Hyung-Ok; Wang, Hao; Lai, Jack H; Bachovchin, William W; Weiner, Louis M

    2005-03-01

    Tumor-associated fibroblasts are functionally and phenotypically distinct from normal fibroblasts that are not in the tumor microenvironment. Fibroblast activation protein is a 95 kDa cell surface glycoprotein expressed by tumor stromal fibroblasts, and has been shown to have dipeptidyl peptidase and collagenase activity. Site-directed mutagenesis at the catalytic site of fibroblast activation protein, Ser624 --> Ala624, resulted in an approximately 100,000-fold loss of fibroblast activation protein dipeptidyl peptidase (DPP) activity. HEK293 cells transfected with wild-type fibroblast activation protein, enzymatic mutant (S624A) fibroblast activation protein, or vector alone, were inoculated subcutaneously into immunodeficient mouse to assess the contribution of fibroblast activation protein enzymatic activity to tumor growth. Overexpression of wild-type fibroblast activation protein showed growth potentiation and enhanced tumorigenicity compared with both fibroblast activation protein S624A and vector-transfected HEK293 xenografts. HEK293 cells transfected with fibroblast activation protein S624A showed tumor growth rates and tumorigenicity potential similar only to vector-transfected HEK293. In vivo assessment of fibroblast activation protein DPP activity of these tumors showed enhanced enzymatic activity of wild-type fibroblast activation protein, with only baseline levels of fibroblast activation protein DPP activity in either fibroblast activation protein S624A or vector-only xenografts. These results indicate that the enzymatic activity of fibroblast activation protein is necessary for fibroblast activation protein-driven tumor growth in the HEK293 xenograft model system. This establishes the proof-of-principle that the enzymatic activity of fibroblast activation protein plays an important role in the promotion of tumor growth, and provides an attractive target for therapeutics designed to alter fibroblast activation protein-induced tumor growth by targeting

  5. Potassium Inhibits Dietary Salt-Induced Transforming Growth Factor-β Production

    PubMed Central

    Ying, Wei-Zhong; Aaron, Kristal; Wang, Pei-Xuan; Sanders, Paul W.

    2009-01-01

    Human and animal studies demonstrate an untoward effect of excess dietary NaCl (salt) intake on cardiovascular function and life span. The endothelium in particular augments the production of transforming growth factor (TGF)-β, a fibrogenic growth factor, in response to excess dietary salt intake. This study explored the initiating mechanism that regulates salt-induced endothelial cell production of TGF-β. Male Sprague-Dawley rats were given diets containing different amounts of NaCl and potassium for 4 days. A bioassay for TGF-β demonstrated increased (35.2%) amounts of active TGF-β in the medium of aortic ring segments from rats on the high-salt diet compared with rats maintained on a 0.3% NaCl diet. Inhibition of the large-conductance, calcium-activated potassium channel inhibited dietary salt-induced vascular production of TGF-β but did not affect production of TGF-β by ring segments from rats on the low-salt diet. Immunohistochemical and Western analyses demonstrated the α subunit of the calcium-activated potassium channel in endothelial cells. Increasing medium [K+] inhibited production of dietary salt-induced vascular production levels of total and active TGF-β but did not alter TGF-β production by aortic rings from rats on the 0.3% NaCl diet. Increasing dietary potassium content decreased urinary active TGF-β in animals receiving the high-salt diet but did not change urinary active TGF-β in animals receiving the low-salt diet. The findings demonstrated an interesting interaction between the dietary intake of potassium and excess NaCl and further showed the fundamental role of the endothelial calcium-activated potassium channel in the vascular response to excess salt intake. PMID:19738156

  6. Biochemical characterization of the Drosophila dpp protein, a member of the transforming growth factor beta family of growth factors.

    PubMed Central

    Panganiban, G E; Rashka, K E; Neitzel, M D; Hoffmann, F M

    1990-01-01

    The decapentaplegic (dpp) gene of Drosophila melanogaster is required for pattern formation in the embryo and for viability of the epithelial cells in the imaginal disks. The dpp protein product predicted from the DNA sequence is similar to members of a family of growth factors that includes transforming growth factor beta (TGF-beta). We have produced polyclonal antibodies to a recombinant dpp protein made in bacteria and used a metallothionein promoter to express a dpp cDNA in Drosophila S2 cells. Similar to other proteins in the TGF-beta family, the dpp protein produced by the Drosophila cells was proteolytically cleaved, and both portions of the protein were secreted from the cells. The amino-terminal 47-kilodalton (kDa) peptide was found in the medium and in the proteins adhering to the plastic petri dish. The carboxy-terminal peptide, the region with sequence similarity to the active ligand portion of TGF-beta, was found extracellularly as a 30-kDa homodimer. Most of the 30-kDa homodimer was in the S2 cell protein adsorbed onto the surface of the plastic dish. The dpp protein could be released into solution by increased salt concentration and nonionic detergent. Under these conditions, the amino-terminal and carboxy-terminal portions of dpp were not associated in a stable complex. Images PMID:1692958

  7. Stress-induced martensitic transformation in metastable austenitic stainless steels: Effect on fatigue crack growth rate

    NASA Astrophysics Data System (ADS)

    Khan, Z.; Ahmed, M.

    1996-04-01

    This paper addresses the influence of cyclic stress-induced martensitic transformation on fatigue crack growth rates in metastable austenitic stainless steels. At low applied stress and mean stress values in AISI type 301 stainless steel, fatigue crack growth rate is substantially retarded due to a cyclic stress-induced γ-α' and γ-ɛ martensitic transformation occurring at the crack-tip plastic zone. It is suggested that the transformation products produce a compressive residual stress at the tip of the fatigue crack, which essentially lowers the effective stress intensity and hence retards the fatigue crack growth rate. At high applied stress or mean stress values, fatigue crack growth rates in AISI type 301 steels become almost equal to those of stable AISI type 302 alloy. As the amount of transformed products increases (with an increase in applied or mean stress), the strain-hardening effect brought about by the transformed martensite phase appears to accelerate fatigue crack growth, offsetting the contribution from the compressive residual stress produced by the positive volume change of γ → α' or ɛ transformation.

  8. The Role of Ect2 Nuclear RhoGEF Activity in Ovarian Cancer Cell Transformation

    PubMed Central

    Huff, Lauren P.; DeCristo, Molly J.; Trembath, Dimitri; Kuan, Pei Fen; Yim, Margaret; Liu, Jinsong; Cook, Danielle R.; Miller, C. Ryan; Der, Channing J.

    2013-01-01

    Ect2, a Rho guanine nucleotide exchange factor (RhoGEF), is atypical among RhoGEFs in its predominantly nuclear localization in interphase cells. One current model suggests that Ect2 mislocalization drives cellular transformation by promoting aberrant activation of cytoplasmic Rho family GTPase substrates. However, in ovarian cancers, where Ect2 is both amplified and overexpressed at the mRNA level, we observed that the protein is highly expressed and predominantly nuclear and that nuclear but not cytoplasmic Ect2 increases with advanced disease. Knockdown of Ect2 in ovarian cancer cell lines impaired their anchorage-independent growth without affecting their growth on plastic. Restoration of Ect2 expression rescued the anchorage-independent growth defect, but not if either the DH catalytic domain or the nuclear localization sequences of Ect2 were mutated. These results suggested a novel mechanism whereby Ect2 could drive transformation in ovarian cancer cells by acting as a RhoGEF specifically within the nucleus. Interestingly, Ect2 had an intrinsically distinct GTPase specificity profile in the nucleus versus the cytoplasm. Nuclear Ect2 bound preferentially to Rac1, while cytoplasmic Ect2 bound to RhoA but not Rac. Consistent with nuclear activation of endogenous Rac, Ect2 overexpression was sufficient to recruit Rac effectors to the nucleus, a process that required a functional Ect2 catalytic domain. Furthermore, expression of active nuclearly targeted Rac1 rescued the defect in transformed growth caused by Ect2 knockdown. Our work suggests a novel mechanism of Ect2-driven transformation, identifies subcellular localization as a regulator of GEF specificity, and implicates activation of nuclear Rac1 in cellular transformation. PMID:24386507

  9. Direct transfer of transforming growth factor beta 1 gene into arteries stimulates fibrocellular hyperplasia.

    PubMed Central

    Nabel, E G; Shum, L; Pompili, V J; Yang, Z Y; San, H; Shu, H B; Liptay, S; Gold, L; Gordon, D; Derynck, R

    1993-01-01

    The arterial wall responds to thrombosis or mechanical injury through the induction of specific gene products that increase cellular proliferation and connective tissue formation. These changes result in intimal hyperplasia that is observed in restenosis and the early phases of atherosclerosis. Transforming growth factor beta 1 (TGF-beta 1) is a secreted multi-functional protein that plays an important role in embryonal development and in repair following tissue injury. However, the function of TGF-beta 1 in vascular cell growth in vivo has not been defined. In this report, we have evaluated the role of TGF-beta 1 in the pathophysiology of intimal and medial hyperplasia by gene transfer of an expression plasmid encoding active TGF-beta 1 into porcine arteries. Expression of TGF-beta 1 in normal arteries resulted in substantial extracellular matrix production accompanied by intimal and medial hyperplasia. Increased procollagen, collagen, and proteoglycan synthesis in the neointima was demonstrated by immunohistochemistry relative to control transfected arteries. Expression of TGF-beta 1 induced a distinctly different program of gene expression and biologic response from the platelet-derived growth factor B (PDGF B) gene: procollagen synthesis induced by TGF-beta 1 was greater, and cellular proliferation was less prominent. These findings show that TGF-beta 1 differentially modulates extracellular matrix production and cellular proliferation in the arterial wall in vivo and could play a reparative role in the response to arterial injury. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 PMID:8248168

  10. Regulation of the ovarian reserve by members of the transforming growth factor beta family

    PubMed Central

    Pangas, Stephanie A.

    2012-01-01

    Genetic or environmental factors that affect the endowment of oocytes, their assembly nto primordial follicles, or their subsequent entry into the growing follicle pool can disrupt reproductive function and may underlie disorders such as primary ovarian insufficiency. Mouse models have been instrumental in identifying genes important in ovarian development, and a number of genes now associated with ovarian dysfunction in women were first identified as causing reproductive defects in knockout mice. The transforming growth factor beta (TGFB) family consists of developmentally important growth factors that include the TGFBs, anti-Müllerian hormone (AMH), activins, bone morphogenetic proteins (BMPs), and growth and differentiation factor 9 (GDF9). The ovarian primordial follicle pool is the source of oocytes in adults. Development of this pool can be grossly divided into three key processes: (1) establishment of oocytes during embryogenesis followed by (2) assembly and (3) activation of the primordial follicle. Disruptions in any of these processes may cause reproductive dysfunction. Most members of the TGFB family show pivotal roles in each of these areas. Understanding the phenotypes of various mouse models for this protein family will be directly relevant to understanding how disruptions in TGFB family signaling result in reproductive diseases in women and will present new areas for development of tailored diagnostics and interventions for infertility. PMID:22847922

  11. Connective tissue growth factor/CCN2-null mouse embryonic fibroblasts retain intact transforming growth factor-{beta} responsiveness

    SciTech Connect

    Mori, Yasuji; Hinchcliff, Monique; Wu, Minghua; Warner-Blankenship, Matthew; Lyons, Karen M.

    2008-03-10

    Background: The matricellular protein connective tissue growth factor (CCN2) has been implicated in pathological fibrosis, but its physiologic role remains elusive. In vitro, transforming growth factor-{beta} (TGF-{beta}) induces CCN2 expression in mesenchymal cells. Because CCN2 can enhance profibrotic responses elicited by TGF-{beta}, it has been proposed that CCN2 functions as an essential downstream signaling mediator for TGF-{beta}. To explore this notion, we characterized TGF-{beta}-induced activation of fibroblasts from CCN2-null (CCN2{sup -/-}) mouse embryos. Methods: The regulation of CCN2 expression was examined in vivo in a model of fibrosis induced by bleomycin. Cellular TGF-{beta} signal transduction and regulation of collagen gene expression were examined in CCN2{sup -/-} MEFs by immunohistochemistry, Northern, Western and RT-PCR analysis, immunocytochemistry and transient transfection assays. Results: Bleomycin-induced skin fibrosis in the mouse was associated with substantial CCN2 up-regulation in lesional fibroblasts. Whereas in vitro proliferation rate of CCN2{sup -/-} MEFs was markedly reduced compared to wild type MEFs, TGF-{beta}-induced activation of the Smad pathways, including Smad2 phosphorylation, Smad2/3 and Smad4 nuclear accumulation and Smad-dependent transcriptional responses, were unaffected by loss of CCN2. The stimulation of COL1A2 and fibronectin mRNA expression and promoter activity, and of corresponding protein levels, showed comparable time and dose-response in wild type and CCN2{sup -/-} MEFs, whereas stimulation of alpha smooth muscle actin and myofibroblast transdifferentiation showed subtle impairment in MEFs lacking CCN2. Conclusion: Whereas endogenous CCN2 plays a role in regulation of proliferation and TGF-{beta}-induced myofibroblast transdifferentiation, it appears to be dispensable for Smad-dependent stimulation of collagen and extracellular matrix synthesis in murine embryonic fibroblasts.

  12. Pin1 promotes transforming growth factor-beta-induced migration and invasion.

    PubMed

    Matsuura, Isao; Chiang, Keng-Nan; Lai, Chen-Yu; He, Dongming; Wang, Guannan; Ramkumar, Romila; Uchida, Takafumi; Ryo, Akihide; Lu, Kunping; Liu, Fang

    2010-01-15

    Transforming growth factor-beta (TGF-beta) regulates a wide variety of biological activities. It induces potent growth-inhibitory responses in normal cells but promotes migration and invasion of cancer cells. Smads mediate the TGF-beta responses. TGF-beta binding to the cell surface receptors leads to the phosphorylation of Smad2/3 in their C terminus as well as in the proline-rich linker region. The serine/threonine phosphorylation sites in the linker region are followed by the proline residue. Pin1, a peptidyl-prolyl cis/trans isomerase, recognizes phosphorylated serine/threonine-proline motifs. Here we show that Smad2/3 interacts with Pin1 in a TGF-beta-dependent manner. We further show that the phosphorylated threonine 179-proline motif in the Smad3 linker region is the major binding site for Pin1. Although epidermal growth factor also induces phosphorylation of threonine 179 and other residues in the Smad3 linker region the same as TGF-beta, Pin1 is unable to bind to the epidermal growth factor-stimulated Smad3. Further analysis suggests that phosphorylation of Smad3 in the C terminus is necessary for the interaction with Pin1. Depletion of Pin1 by small hairpin RNA does not significantly affect TGF-beta-induced growth-inhibitory responses and a number of TGF-beta/Smad target genes analyzed. In contrast, knockdown of Pin1 in human PC3 prostate cancer cells strongly inhibited TGF-beta-mediated migration and invasion. Accordingly, TGF-beta induction of N-cadherin, which plays an important role in migration and invasion, is markedly reduced when Pin1 is depleted in PC3 cells. Because Pin1 is overexpressed in many cancers, our findings highlight the importance of Pin1 in TGF-beta-induced migration and invasion of cancer cells. PMID:19920136

  13. Valproic acid overcomes transforming growth factor-β-mediated sorafenib resistance in hepatocellular carcinoma

    PubMed Central

    Matsuda, Yasunobu; Wakai, Toshifumi; Kubota, Masayuki; Osawa, Mami; Hirose, Yuki; Sakata, Jun; Kobayashi, Takashi; Fujimaki, Shun; Takamura, Masaaki; Yamagiwa, Satoshi; Aoyagi, Yutaka

    2014-01-01

    Sorafenib is a multi-kinase inhibitor approved for hepatocellular carcinoma, but rarely causes tumor regression in patients with chronic liver diseases. To investigate whether growth factor-mediated signaling is involved in sorafenib resistance, HepG2 and PLC/PRF/5 hepatoma cells were exposed to epidermal growth factor (EGF), hepatocyte growth factor (HGF) or transforming growth factor-β (TGF-β) prior to treatment with sorafenib. Furthermore, to identify an effective combination treatment with sorafenib, growth factor-sensitized cells were treated with sorafenib alone or in combination with celecoxib, lovastatin or valproic acid (VPA). Trypan blue staining and Annexin V assays showed that the cytotoxic effect of sorafenib was inhibited by 15-54% in cells sensitized to TGF-β (P<0.05). Western blotting analysis showed that TGF-β significantly activated extracellular signal-regulated kinase (ERK)-mediated AKT signaling, and sorafenib failed to suppress both ERK and AKT in TGF-β-sensitized cells. The decreased anti-tumor effect of sorafenib was rescued by chemical inhibition of ERK and AKT. When TGF-β-sensitized cells were treated with sorafenib plus VPA, the levels of phosphorylated ERK and AKT were considerably suppressed and the numbers of dead cells were increased by 3.7-5.7-fold compared with those exposed to sorafenib alone (P<0.05). Moreover, low dose sorafenib-induced cell migration was effectively suppressed by combination treatment with sorafenib and VPA. Collectively, TGF-β/ERK/AKT signaling might play a critical role in sorafenib resistance in hepatoma cells, and combination treatment with VPA may be effective against this drug resistance. PMID:24817927

  14. Role of transforming growth factor-beta (TGF) beta in the physiopathology of rheumatoid arthritis.

    PubMed

    Gonzalo-Gil, Elena; Galindo-Izquierdo, María

    2014-01-01

    Transforming growth factor-beta (TGF-β) is a cytokine with pleiotropic functions in hematopoiesis, angiogenesis, cell proliferation, differentiation, migration and apoptosis. Although its role in rheumatoid arthritis is not well defined, TGF-β activation leads to functional immunomodulatory effects according to environmental conditions. The function of TGF-β in the development of arthritis in murine models has been extensively studied with controversial results. Recent findings point to a non-relevant role for TGF-β in a mice model of collagen-induced arthritis. The study of TGF-β on T-cell responses has shown controversial results as an inhibitor or promoter of the inflammatory response. This paper presents a review of the role of TGF-β in animal models of arthritis. PMID:24685296

  15. Stromal inhibition of prostatic epithelial cell proliferation not mediated by transforming growth factor beta.

    PubMed Central

    Kooistra, A.; van den Eijnden-van Raaij, A. J.; Klaij, I. A.; Romijn, J. C.; Schröder, F. H.

    1995-01-01

    The paracrine influence of prostatic stroma on the proliferation of prostatic epithelial cells was investigated. Stromal cells from the human prostate have previously been shown to inhibit anchorage-dependent as well as anchorage-independent growth of the prostatic tumour epithelial cell lines PC-3 and LNCaP. Antiproliferative activity, mediated by a diffusible factor in the stromal cell conditioned medium, was found to be produced specifically by prostatic stromal cells. In the present study the characteristics of this factor were examined. It is demonstrated that prostate stroma-derived inhibiting factor is an acid- and heat-labile, dithiothreitol-sensitive protein. Although some similarities with type beta transforming growth factor (TGF-beta)-like inhibitors are apparent, evidence is presented that the factor is not identical to TGF-beta or to the TGF-beta-like factors activin and inhibin. Absence of TGF-beta activity was shown by the lack of inhibitory response of the TGF-beta-sensitive mink lung cell line CCL-64 to prostate stromal cell conditioned medium and to concentrated, partially purified preparations of the inhibitor. Furthermore, neutralising antibodies against TGF-beta 1 or TGF-beta 2 did not cause a decline in the level of PC-3 growth inhibition caused by partially purified inhibitor. Using Northern blot analyses, we excluded the involvement of inhibin or activin. It is concluded that the prostate stroma-derived factor may be a novel growth inhibitor different from any of the currently described inhibiting factors. Images Figure 5 PMID:7543773

  16. Substrate flexibility regulates growth and apoptosis of normal but not transformed cells

    NASA Technical Reports Server (NTRS)

    Wang, H. B.; Dembo, M.; Wang, Y. L.

    2000-01-01

    One of the hallmarks of oncogenic transformation is anchorage-independent growth (27). Here we demonstrate that responses to substrate rigidity play a major role in distinguishing the growth behavior of normal cells from that of transformed cells. We cultured normal or H-ras-transformed NIH 3T3 cells on flexible collagen-coated polyacrylamide substrates with similar chemical properties but different rigidity. Compared with cells cultured on stiff substrates, nontransformed cells on flexible substrates showed a decrease in the rate of DNA synthesis and an increase in the rate of apoptosis. These responses on flexible substrates are coupled to decreases in cell spreading area and traction forces. In contrast, transformed cells maintained their growth and apoptotic characteristics regardless of substrate flexibility. The responses in cell spreading area and traction forces to substrate flexibility were similarly diminished. Our results suggest that normal cells are capable of probing substrate rigidity and that proper mechanical feedback is required for regulating cell shape, cell growth, and survival. The loss of this response can explain the unregulated growth of transformed cells.

  17. Smad-Independent Transforming Growth Factor-β Regulation of Early Growth Response-1 and Sustained Expression in Fibrosis

    PubMed Central

    Bhattacharyya, Swati; Chen, Shu-Jen; Wu, Minghua; Warner-Blankenship, Matthew; Ning, Hongyan; Lakos, Gabriella; Mori, Yasuji; Chang, Eric; Nihijima, Chihiro; Takehara, Kazuhiro; Feghali-Bostwick, Carol; Varga, John

    2008-01-01

    Transforming growth factor-β (TGF-β) plays a key role in scleroderma pathogenesis. The transcription factor early growth response-1 (Egr-1) mediates the stimulation of collagen transcription elicited by TGF-β and is necessary for the development of pulmonary fibrosis in mice. Here, we report that TGF-β causes a time- and dose-dependent increase in Egr-1 protein and mRNA levels and enhanced transcription of the Egr-1 gene via serum response elements in normal fibroblasts. The ability of TGF-β to stimulate Egr-1 was preserved in Smad3-null mice and in explanted Smad3-null fibroblasts. The response was blocked by a specific mitogen-activated protein kinase kinase 1 (MEK1) inhibitor but not by an ALK5 kinase inhibitor. Furthermore, MEK1 was phosphorylated by TGF-β, which was sufficient to drive Egr-1 transactivation. Stimulation by TGF-β enhanced the transcriptional activity of Elk-1 via the MEK-extracellular signal-regulated kinase 1/2 pathway. Bleomycin-induced scleroderma in the mouse was accompanied by increased Egr-1 accumulation in lesional fibroblasts. Furthermore, biopsies of lesional skin and lung from patients with scleroderma showed increased Egr-1 levels, which were highest in early diffuse disease. Moreover, both Egr-1 mRNA and protein were elevated in explanted scleroderma skin fibroblasts in vitro. Together, these findings define a Smad-independent TGF-β signal transduction mechanism that underlies the stimulation of Egr-1, demonstrate for the first time sustained Egr-1 up-regulation in fibrotic lesions and suggests that Egr-1 has a role in the induction and progression of fibrosis. PMID:18772333

  18. Non-instantaneous growth characteristics of martensitic transformation in high Cr ferritic creep-resistant steel

    NASA Astrophysics Data System (ADS)

    Liu, Chenxi; Shao, Yi; Chen, Jianguo; Liu, Yongchang

    2016-08-01

    Microstructural observation and high-resolution dilatometry were employed to investigate kinetics of martensitic transformation in high Cr ferritic creep-resistant steel upon different quenching/cooling rates. By incorporating the classical athermal nucleation and impingement correction, a non-instantaneous growth model for martensitic transformation has been developed. The developed model describes austenite/martensite interface mobility during martensite growth. The growth rate of martensite is found to be varied from 1 × 10-6 to 3 × 10-6 m/s. The low interface mobility suggests that it is not appropriate to presume the instantaneous growth behavior of martensite. Moreover, based on the proposed model, nucleation rate of martensite under different cooling rates is found to be nearly the same, while the growth rate of martensite is promoted by increasing the cooling rate.

  19. Transforming Growth Factor-Beta and Oxidative Stress Interplay: Implications in Tumorigenesis and Cancer Progression

    PubMed Central

    Krstić, Jelena; Trivanović, Drenka; Mojsilović, Slavko; Santibanez, Juan F.

    2015-01-01

    Transforming growth factor-beta (TGF-β) and oxidative stress/Reactive Oxygen Species (ROS) both have pivotal roles in health and disease. In this review we are analyzing the interplay between TGF-β and ROS in tumorigenesis and cancer progression. They have contradictory roles in cancer progression since both can have antitumor effects, through the induction of cell death, senescence and cell cycle arrest, and protumor effects by contributing to cancer cell spreading, proliferation, survival, and metastasis. TGF-β can control ROS production directly or by downregulating antioxidative systems. Meanwhile, ROS can influence TGF-β signaling and increase its expression as well as its activation from the latent complex. This way, both are building a strong interplay which can be taken as an advantage by cancer cells in order to increment their malignancy. In addition, both TGF-β and ROS are able to induce cell senescence, which in one way protects damaged cells from neoplastic transformation but also may collaborate in cancer progression. The mutual collaboration of TGF-β and ROS in tumorigenesis is highly complex, and, due to their differential roles in tumor progression, careful consideration should be taken when thinking of combinatorial targeting in cancer therapies. PMID:26078812

  20. Cross-Talk Between Nitric Oxide and Transforming Growth Factor-β1 in Malaria

    PubMed Central

    Vodovotz, Yoram; Zamora, Ruben; Lieber, Matthew J.; Luckhart, Shirley

    2008-01-01

    Malaria has re-emerged as a global health problem, leading to an increased focus on the cellular and molecular biology of the mosquito Anopheles and the parasite Plasmodium with the goal of identifying novel points of intervention in the parasite life cycle. Anti-parasite defenses mounted by both mammalian hosts and Anopheles can suppress the growth of Plasmodium. Nonetheless, the parasite is able to escape complete elimination in vivo, perhaps by thwarting or co-opting these mechanisms for its own survival, as do numerous other pathogens. Among the defense systems used by the mammalian host against Plasmodium is the synthesis of nitric oxide (NO), catalyzed by an inducible NO synthase (iNOS). Nitric oxide produced by the action of an inducible Anopheles stephensi NO synthase (AsNOS) may be central to the anti-parasitic arsenal of this mosquito. In mammals, iNOS can be modulated by members of the transforming growth factor-β (TGF-β) cytokine superfamily. Transforming growth factor-β is produced as an inactive precursor that is activated following dissociation of certain inhibitory proteins, a process that can be promoted by reaction products of NO as well as by hemin. Ingestion by Anopheles of blood containing Plasmodium initiates parasite development, blood digestion which results in the accumulation of hematin (hemin) in the insect midgut, and induction of both AsNOS and TGF-β-like (As60A) gene expression in the midgut epithelium. Active mammalian TGF-β1 can be detected in the A. stephensi midgut up to 48h post-ingestion and latent TGF-β1 can be activated by midgut components in vitro, a process that is potentiated by NO and that may involve hematin. Further, mammalian TGF-β1 is perceived as a cytokine by A. stephensi cells in vitro and can alter Plasmodium development in vivo. Bloodfeeding by Anopheles, therefore, results in a juxtaposition of evolutionarily conserved mosquito and mammalian TGF-β superfamily homologs that may influence transmission

  1. Learning Activities for the Growth Season.

    ERIC Educational Resources Information Center

    Darby, Linda, Ed.

    This poster, illustrated with a graphic of a caterpillar changing to a cocoon and emerging as a butterfly, presents learning activities for 7 weeks based on the seven stages of growth in the President's "Call to Action." Each week includes 5 days of activities based on seven themes: (1) "Reading on Your Own"; (2) "Getting Ready for Algebra"; (3)…

  2. Transforming growth factor-beta during carcinogenesis: the shift from epithelial to mesenchymal signaling.

    PubMed

    Matsuzaki, Koichi; Okazaki, Kazuichi

    2006-04-01

    Transforming growth factor-beta (TGF-beta) activates not only TGF-beta type I receptor (TbetaRI) but also c-Jun N-terminal kinase (JNK), changing unphosphorylated Smad3 to its phosphoisoforms: C-terminally phosphorylated Smad3 (pSmad3C) and linker phosphorylated Smad3 (pSmad3L). While the TbetaRI/pSmad3C pathway inhibits growth of normal epithelial cells, JNK/pSmad3L-mediated signaling is involved in invasion by activated mesenchymal cells. During sporadic human colorectal carcinogenesis, TGF-beta signaling confers a selective advantage on tumor cells by shifting from the TbetaRI/pSmad3C pathway characteristic of mature epithelial cells to the JNK/pSmad3L pathway, which is more characteristic of the state of flux shown by the activated mesenchymal cells. JNK acts as a regulator of TGF-beta signaling by increasing the basal level of pSmad3L available for action in the nuclei of the invasive adenocarcinoma, in the meantime shutting down TGF-beta-dependent nuclear activity of pSmad3C. Loss of epithelial homeostasis and acquisition of a migratory, mesenchymal phenotype are essential for tumor invasion. From the viewpoint of TGF-beta signaling, a key therapeutic aim in cancer would be restoration of the lost tumor suppressor function observed in normal colorectal epithelial cells at the expense of effects promoting aggressive behavior of the adenocarcinoma. Specific inhibitors of the JNK/pSmad3L pathway might prove useful in this respect. In the case of molecularly targeted therapy for human cancer, pSmad3L and pSmad3C could be assessed as biomarkers to evaluate the likely benefit from specific inhibition of the JNK/pSmad3L pathway. PMID:16741607

  3. Notch1 signaling antagonizes transforming growth factor-β pathway and induces apoptosis in rabbit trophoblast stem cells.

    PubMed

    Tan, Tao; Lu, Bin; Zhang, Jing; Niu, Yuyu; Si, Wei; Wei, Qiang; Ji, Weizhi

    2014-04-15

    During mammalian development, placental growth needs to be tightly controlled by apoptosis. However, despite the potentially significant problems, the strategies used to balance growth and apoptosis have remained elusive. Here we report that activation of the Notch1 signal pathway inhibits transduction of transforming growth factor (TGF)-β signaling, which leads to cell cycle arrest and apoptosis in rabbit trophoblast stem cells (TSCs). The subcellular location of notch intracellular domain 1 (NICD1) appears to determine whether TGF-β signaling will be inhibited or not. Moreover, changes in NICD1 subcellular location are regulated by intracellular calcium distribution. Collectively, these results establish a potential mechanism whereby TSCs can balance growth and apoptosis, and thus guarantee the development of the fetus. PMID:24251382

  4. The suppression of fibroblast growth factor 2/fibroblast growth factor 4-dependent tumour angiogenesis and growth by the anti-growth factor activity of dextran derivative (CMDB7).

    PubMed Central

    Bagheri-Yarmand, R.; Kourbali, Y.; Mabilat, C.; Morère, J. F.; Martin, A.; Lu, H.; Soria, C.; Jozefonvicz, J.; Crépin, M.

    1998-01-01

    Our previous studies showed that carboxymethyl benzylamide dextran (CMDB7) blocks basic fibroblast growth factor (FGF-2)-dependent cell proliferation of a human breast epithelial line (HBL100), suggesting its potential role as a potent antiangiogenic substance. The derived cell line (HH9), which was transformed with the hst/FGF4 gene, has been shown to be highly proliferative in vitro and to induce angiogenic tumours in nude mice. We show here that CMDB7 inhibits the mitogenic activities of the conditioned media from HBL 100 and HH9 cells in a dose-dependent manner. When HH9 cells were injected s.c. into nude mice, CMDB7 treatment (300 mg kg(-1) week(-1)) suppressed the tumour take and the tumour growth by about 50% and 80% respectively. Immunohistochemical analysis showed a highly significant decrease, by more than threefold, in the endothelial density of viable tumour regions, together with a significant increase in the necrosis area. This antiangiogenic activity of CMDB7 was further demonstrated by direct inhibition of calf pulmonary artery (CPAE) and human umbilical vein (HUVEC) endothelial cell proliferation and migration in vitro. In addition, we showed that CMDB7 inhibits specifically the mitogenic effects of the growth factors that bind to heparin such as FGF-2, FGF-4, platelet-derived growth factor (PDGF-BB) and transforming growth factor (TGF-beta1), but not those of epidermal growth factor (EGF) and insulin-like growth factor (IGF-1). These results demonstrate that CMDB7 inhibits FGF-2/FGF-4-dependent tumour growth and angiogenesis, most likely by disrupting the autocrine and paracrine effects of growth factors released from the tumour cells. Images Figure 4 PMID:9662260

  5. Bereavement and transformation: a psycho-spiritual and post-traumatic growth perspective.

    PubMed

    Bray, Peter

    2013-09-01

    In the aftermath of loss, it is not uncommon for individuals to disclose psycho-spiritual experiences that lead to personal changes and psychological growth. This article argues for and outlines a broad conceptual framework that captures and acknowledges the significance of these subjective experiences. The model synthesises and integrates two approaches to healthy growth: Lawrence Calhoun and Richard Tedeschi's post-traumatic growth model and Stanislav and Christina Grof's model of psycho-spiritual transformation. A rationale for a broader model and underpinning theory is briefly discussed, and their shared understandings about the human potential for growth in the struggle through loss are explored. PMID:21948147

  6. Enhanced jun gene expression is an early genomic response to transforming growth factor. beta. stimulation

    SciTech Connect

    Pertovaara, L.; Sistonen, L.; Keski-Oja, J.; Alitalo, K. ); Bos, T.J.; Vogt, P.K. . Dept. of Microbiology)

    1989-03-01

    Transforming growth factor {beta} (TGF{beta}) is a multifunctional polypeptide4 that regulates proliferation, differentiation, and other functions of many cell types. The pathway of TGF{beta} signal transduction in cells is unknown. The authors report here that an early effect of TGF{beta} is an enhancement of the expression of two genes encoding serum- and phorbol ester tumor promoter-regulated transcription factors: the junB gene and the c-jun proto-oncogene, respectively. This stimulation was observed in human lung adenocarcinoma A549 cells which were growth inhibited by TGF{beta}, AKR-2B mouse embryo fibroblasts which were growth stimulated by TGF{beta}, and K562 human erythroleukemia cells, which were not appreciably affected in their growth by TFG{beta}. The increase in jun mRNA occurred with picomolar TGF{beta} concentrations within 1 h of TGF{beta} stimulation, reached a peak between 1 and 5 h in different cells, and declined gradually to base-fine levels. This mRNA response was followed by a large increase in the biosynthesis of the c-jun protein (AP-1), as shown by metabolic labeling and immunoprecipitation analysis. However, differential and cell type-specific regulation appeared to determine the timing and magnitude of the response of each jun gene in a given cell. In AKR-2B and NIH 3T3 cells, only junB was induced by TGF{beta}, evidently in a protein synthesis-independent fashion. The junB response to TGF{beta} was maintained in c-Ha-ras and neu oncogene-transformed cells. Thus, one of the earliest genomic responses to TGF{beta} may involve nuclear signal transduction and amplification by the junB and c-jun transcription factors in concert with c-fos, which is also induced. The differential activation of the jun genes may explain some of the pleiotropic effects of TGF{beta}.

  7. Transforming growth factor beta 3 involved in the pathogenesis of synovial chondromatosis of temporomandibular joint

    PubMed Central

    Li, Yingjie; El.Mozen, Loaye Abdelaziz; Cai, Hengxing; Fang, Wei; Meng, Qinggong; Li, Jian; Deng, Mohong; Long, Xing

    2015-01-01

    Synovial chondromatosis (SC) of temporomandibular joint is rare proliferative disorder featured by the formation of cartilaginous nodules in synovium and joint space. Transforming growth factor beta 3 (TGF-β3) is closely related to chondrogenic differentiation, and might participate in pathogenesis of SC. We discovered that increased quantity of synoviocytes and blood vessels were observed in SC synovium. The vessel wall and sublining fibroblasts were stained positively by the antibodies against TGF-β3, fibroblast growth factor 2 (FGF-2), and CD34. In loose bodies (LBs), TGF-β3 was mainly expressed in chondrocytes and FGF-2 was expressed in chondrocytes, fibroblasts, and vessel walls. Expressions of TGF-β1, TGF-β3, FGF-2, Sox9, Wnt-4, Foxc2, and VEGF-A mRNA were significantly higher in SC synovium. Stimulation of TGF-β3 on synoviocytes increased alkaline phosphatase (ALP) activity and expressions of chondrogenic genes (Sox9, Col2α1, Aggrecan, Wnt-4, and Wnt-11), osteogenic genes (Runx2, Foxc2, osteocalcin, and Col1α1), and VEGF-A, but failed to influence FGF-2 expression. However, the addition of FGF-2 increased TGF-β3 expression. In conclusion, TGF-β3 existed in synovium and LBs of SC, and was responsible for the pathogenesis of SC. PMID:25742744

  8. Transforming growth factor beta 3 involved in the pathogenesis of synovial chondromatosis of temporomandibular joint.

    PubMed

    Li, Yingjie; El Mozen, Loaye Abdelaziz; Cai, Hengxing; Fang, Wei; Meng, Qinggong; Li, Jian; Deng, Mohong; Long, Xing

    2015-01-01

    Synovial chondromatosis (SC) of temporomandibular joint is rare proliferative disorder featured by the formation of cartilaginous nodules in synovium and joint space. Transforming growth factor beta 3 (TGF-β3) is closely related to chondrogenic differentiation, and might participate in pathogenesis of SC. We discovered that increased quantity of synoviocytes and blood vessels were observed in SC synovium. The vessel wall and sublining fibroblasts were stained positively by the antibodies against TGF-β3, fibroblast growth factor 2 (FGF-2), and CD34. In loose bodies (LBs), TGF-β3 was mainly expressed in chondrocytes and FGF-2 was expressed in chondrocytes, fibroblasts, and vessel walls. Expressions of TGF-β1, TGF-β3, FGF-2, Sox9, Wnt-4, Foxc2, and VEGF-A mRNA were significantly higher in SC synovium. Stimulation of TGF-β3 on synoviocytes increased alkaline phosphatase (ALP) activity and expressions of chondrogenic genes (Sox9, Col2α1, Aggrecan, Wnt-4, and Wnt-11), osteogenic genes (Runx2, Foxc2, osteocalcin, and Col1α1), and VEGF-A, but failed to influence FGF-2 expression. However, the addition of FGF-2 increased TGF-β3 expression. In conclusion, TGF-β3 existed in synovium and LBs of SC, and was responsible for the pathogenesis of SC. PMID:25742744

  9. Tumor-promoting functions of transforming growth factor-β in progression of cancer

    PubMed Central

    2012-01-01

    Transforming growth factor-β (TGF-β) elicits both tumor-suppressive and tumor-promoting functions during cancer progression. Here, we describe the tumor-promoting functions of TGF-β and how these functions play a role in cancer progression. Normal epithelial cells undergo epithelial-mesenchymal transition (EMT) through the action of TGF-β, while treatment with TGF-β and fibroblast growth factor (FGF)-2 results in transdifferentiation into activated fibroblastic cells that are highly migratory, thereby facilitating cancer invasion and metastasis. TGF-β also induces EMT in tumor cells, which can be regulated by oncogenic and anti-oncogenic signals. In addition to EMT promotion, invasion and metastasis of cancer are facilitated by TGF-β through other mechanisms, such as regulation of cell survival, angiogenesis, and vascular integrity, and interaction with the tumor microenvironment. TGF-β also plays a critical role in regulating the cancer-initiating properties of certain types of cells, including glioma-initiating cells. These findings thus may be useful for establishing treatment strategies for advanced cancer by inhibiting TGF-β signaling. PMID:22111550

  10. alpha1B-Adrenergic receptor phosphorylation and desensitization induced by transforming growth factor-beta.

    PubMed Central

    Romero-Avila, M Teresa; Flores-Jasso, C Fabián; García-Sáinz, J Adolfo

    2002-01-01

    Transforming growth factor-beta (TGF-beta) induced alpha(1B)-adrenergic receptor phosphorylation in Rat-1 fibroblasts stably expressing these adrenoceptors. This effect of TGF-beta was rapid, reaching a maximum within 30 min and decreasing thereafter, and concentration-dependent (EC(50) 0.3 pM). The phosphoinositide 3-kinase inhibitors wortmannin and LY294002, and the protein kinase C inhibitors staurosporine, Ro 318220 and bisindolylmaleimide, blocked the effect of this growth factor. alpha(1B)-Adrenergic receptor phosphorylation was associated with desensitization, as indicated by a reduction in the adrenergic-mediated production of [(3)H]inositol phosphates. Phosphorylation of alpha(1B)-adrenergic receptors by TGF-beta was also observed in Cos-1 cells transfected with the receptor. Co-transfection of the dominant-negative mutant of the regulatory subunit of phosphoinositide 3-kinase (Deltap85) inhibited the phosphorylation of alpha(1B)-adrenergic receptors induced by TGF-beta. Our results indicate that activation of TGF-beta receptors induces alpha(1B)-adrenergic receptor phosphorylation and desensitization. The data suggest that phosphoinositide 3-kinase and protein kinase C play key roles in this effect of TGF-beta. PMID:12234252

  11. alpha1B-Adrenergic receptor phosphorylation and desensitization induced by transforming growth factor-beta.

    PubMed

    Romero-Avila, M Teresa; Flores-Jasso, C Fabián; García-Sáinz, J Adolfo

    2002-12-01

    Transforming growth factor-beta (TGF-beta) induced alpha(1B)-adrenergic receptor phosphorylation in Rat-1 fibroblasts stably expressing these adrenoceptors. This effect of TGF-beta was rapid, reaching a maximum within 30 min and decreasing thereafter, and concentration-dependent (EC(50) 0.3 pM). The phosphoinositide 3-kinase inhibitors wortmannin and LY294002, and the protein kinase C inhibitors staurosporine, Ro 318220 and bisindolylmaleimide, blocked the effect of this growth factor. alpha(1B)-Adrenergic receptor phosphorylation was associated with desensitization, as indicated by a reduction in the adrenergic-mediated production of [(3)H]inositol phosphates. Phosphorylation of alpha(1B)-adrenergic receptors by TGF-beta was also observed in Cos-1 cells transfected with the receptor. Co-transfection of the dominant-negative mutant of the regulatory subunit of phosphoinositide 3-kinase (Deltap85) inhibited the phosphorylation of alpha(1B)-adrenergic receptors induced by TGF-beta. Our results indicate that activation of TGF-beta receptors induces alpha(1B)-adrenergic receptor phosphorylation and desensitization. The data suggest that phosphoinositide 3-kinase and protein kinase C play key roles in this effect of TGF-beta. PMID:12234252

  12. Demonstration of single crystal growth via solid-solid transformation of a glass

    DOE PAGESBeta

    Savytskii, Dmytro; Knorr, Brian; Dierolf, Volkmar; Jain, Himanshu

    2016-03-18

    Many advanced technologies have relied on the availability of single crystals of appropriate material such as silicon for microelectronics or superalloys for turbine blades. Similarly, many promising materials could unleash their full potential if they were available in a single crystal form. However, the current methods are unsuitable for growing single crystals of these oftentimes incongruently melting, unstable or metastable materials. Here we demonstrate a strategy to overcome this hurdle by avoiding the gaseous or liquid phase, and directly converting glass into a single crystal. Specifically, Sb2S3 single crystals are grown in Sb-S-I glasses as an example of this approach.more » In this first unambiguous demonstration of an all-solid-state glass → crystal transformation, extraneous nucleation is avoided relative to crystal growth via spatially localized laser heating and inclusion of a suitable glass former in the composition. Lastly, the ability to fabricate patterned single-crystal architecture on a glass surface is demonstrated, providing a new class of micro-structured substrate for low cost epitaxial growth, active planar devices, etc.« less

  13. Demonstration of single crystal growth via solid-solid transformation of a glass.

    PubMed

    Savytskii, Dmytro; Knorr, Brian; Dierolf, Volkmar; Jain, Himanshu

    2016-01-01

    Many advanced technologies have relied on the availability of single crystals of appropriate material such as silicon for microelectronics or superalloys for turbine blades. Similarly, many promising materials could unleash their full potential if they were available in a single crystal form. However, the current methods are unsuitable for growing single crystals of these oftentimes incongruently melting, unstable or metastable materials. Here we demonstrate a strategy to overcome this hurdle by avoiding the gaseous or liquid phase, and directly converting glass into a single crystal. Specifically, Sb2S3 single crystals are grown in Sb-S-I glasses as an example of this approach. In this first unambiguous demonstration of an all-solid-state glass → crystal transformation, extraneous nucleation is avoided relative to crystal growth via spatially localized laser heating and inclusion of a suitable glass former in the composition. The ability to fabricate patterned single-crystal architecture on a glass surface is demonstrated, providing a new class of micro-structured substrate for low cost epitaxial growth, active planar devices, etc. PMID:26988919

  14. Demonstration of single crystal growth via solid-solid transformation of a glass

    NASA Astrophysics Data System (ADS)

    Savytskii, Dmytro; Knorr, Brian; Dierolf, Volkmar; Jain, Himanshu

    2016-03-01

    Many advanced technologies have relied on the availability of single crystals of appropriate material such as silicon for microelectronics or superalloys for turbine blades. Similarly, many promising materials could unleash their full potential if they were available in a single crystal form. However, the current methods are unsuitable for growing single crystals of these oftentimes incongruently melting, unstable or metastable materials. Here we demonstrate a strategy to overcome this hurdle by avoiding the gaseous or liquid phase, and directly converting glass into a single crystal. Specifically, Sb2S3 single crystals are grown in Sb-S-I glasses as an example of this approach. In this first unambiguous demonstration of an all-solid-state glass → crystal transformation, extraneous nucleation is avoided relative to crystal growth via spatially localized laser heating and inclusion of a suitable glass former in the composition. The ability to fabricate patterned single-crystal architecture on a glass surface is demonstrated, providing a new class of micro-structured substrate for low cost epitaxial growth, active planar devices, etc.

  15. Demonstration of single crystal growth via solid-solid transformation of a glass

    PubMed Central

    Savytskii, Dmytro; Knorr, Brian; Dierolf, Volkmar; Jain, Himanshu

    2016-01-01

    Many advanced technologies have relied on the availability of single crystals of appropriate material such as silicon for microelectronics or superalloys for turbine blades. Similarly, many promising materials could unleash their full potential if they were available in a single crystal form. However, the current methods are unsuitable for growing single crystals of these oftentimes incongruently melting, unstable or metastable materials. Here we demonstrate a strategy to overcome this hurdle by avoiding the gaseous or liquid phase, and directly converting glass into a single crystal. Specifically, Sb2S3 single crystals are grown in Sb-S-I glasses as an example of this approach. In this first unambiguous demonstration of an all-solid-state glass → crystal transformation, extraneous nucleation is avoided relative to crystal growth via spatially localized laser heating and inclusion of a suitable glass former in the composition. The ability to fabricate patterned single-crystal architecture on a glass surface is demonstrated, providing a new class of micro-structured substrate for low cost epitaxial growth, active planar devices, etc. PMID:26988919

  16. Role of Ras signaling in the induction of snail by transforming growth factor-beta.

    PubMed

    Horiguchi, Kana; Shirakihara, Takuya; Nakano, Ayako; Imamura, Takeshi; Miyazono, Kohei; Saitoh, Masao

    2009-01-01

    The epithelial-mesenchymal transition (EMT) is a crucial morphological event that occurs during the progression of epithelial tumors. EMT can be induced by transforming growth factor (TGF)-beta in some tumor cells. Here, we demonstrate the molecular mechanism whereby Snail, a key regulator of EMT, is induced by TGF-beta in tumor cells. Snail induction by TGF-beta was highly dependent on cooperation with active Ras signals, and silencing of Ras abolished Snail induction by TGF-beta in pancreatic cancer Panc-1 cells. Transfection of constitutively active Ras into HeLa cells led to induction of Snail by TGF-beta, while representative direct targets of TGF-beta, including Smad7 and PAI-1, were not affected by Ras signaling. Using mitogen-activated protein kinase inhibitors or Smad3 or Smad2 mutants, we found that phosphorylation at the linker region of Smad2/3 was not required for the induction of Snail by TGF-beta. Taken together, these findings indicate that Ras and TGF-beta-Smad signaling selectively cooperate in the induction of Snail, which occurs in a Smad-dependent manner, but independently of phosphorylation at the linker region of R-Smads by Ras signaling. PMID:19010789

  17. Transforming Growth Factor {beta} Can Stimulate Smad1 Phosphorylation Independently of Bone Morphogenic Protein Receptors.

    PubMed

    Wrighton, Katharine H; Lin, Xia; Yu, Paul B; Feng, Xin-Hua

    2009-04-10

    Transforming growth factor-beta (TGFbeta) superfamily ligands control a diverse set of cellular processes by activating type I and type II serine-threonine receptor kinases. Canonical TGFbeta signaling is mediated via the TbetaRI/ALK5 type I receptor that phosphorylates Smad2 and Smad3 in their SXS motif to facilitate their activation and subsequent role in transcriptional regulation. Canonical bone morphogenic protein (BMP) signaling is mediated via the ALK1/2/3/6 type I receptors that phosphorylate Smad1, Smad5, and Smad8 in their SXS motif. However, studies in endothelial cells have shown that TGFbeta can also lead to the phosphorylation of Smad1, dependent on ALK1 receptor activity. Here we present data showing that TGFbeta can significantly induce Smad1 phosphorylation in several non-endothelial cell lineages. Additionally, by using chemical inhibitors specific for the TGFbeta/activin/nodal (ALK4/5/7) and BMP (ALK1/2/3/6) type I receptors, we show that in some cell types TGFbeta induces Smad1 phosphorylation independently of the BMP type I receptors. Thus, TGFbeta-mediated Smad1 phosphorylation appears to occur via different receptor complexes in a cell type-specific manner. PMID:19224917

  18. MTMR4 attenuates transforming growth factor beta (TGFbeta) signaling by dephosphorylating R-Smads in endosomes.

    PubMed

    Yu, Junjing; Pan, Lei; Qin, Xincheng; Chen, Hua; Xu, Youli; Chen, Yeguang; Tang, Hong

    2010-03-12

    Homeostasis of Smad phosphorylation at its C-terminal SXS motif is essential for transforming growth factor beta (TGFbeta) signaling. Whereas it is known that TGFbeta signaling can be terminated by phosphatases, which dephosphorylate R-Smads in the nucleus, it is unclear whether there are any cytoplasmic phosphatase(s) that can attenuate R-Smad phosphorylation and nuclear translocation. Here we demonstrate that myotubularin-related protein 4 (MTMR4), a FYVE domain-containing dual-specificity protein phosphatase (DSP), attenuates TGFbeta signaling by reducing the phosphorylation level of R-Smads in early endosomes. Co-immunoprecipitation experiments showed that endogenous MTMR4 interacts with phosphorylated R-Smads, and that this interaction is correlated with dephosphorylation of R-Smads. Further analysis showed that overexpression of MTMR4 resulted in the sequestration of activated Smad3 in the early endosomes, thus reducing its nuclear translocation. However, both point mutations at the conserved catalytic site of the phosphatase (MTMR4-C407S) and small interference RNA of endogenous Mtmr4 expression led to sustained Smad3 activation. This work therefore suggests that MTMR4 plays an important role in preventing the overactivation of TGFbeta signaling by dephosphorylating activated R-Smads that have been trafficked to early endosomes. PMID:20061380

  19. Characterization and estrogen regulation of uterine growth factor activity

    SciTech Connect

    Beck, C.A.

    1988-01-01

    Acid extracts of rat, bovine and rabbit uterus stimulated glucose transport, measured by phosphorylation of 2-deoxyglucose and DNA synthesis, measured by {sup 3}H-thymidne incorporation, in uterine tumor cells and in primary cultures of rat uterine cells. The stimulation of glucose transport was of the same magnitude and followed the same time course as estradiol stimulation in vivo. Uteri from estradiol-treated rat uteri contained 4 times more glucose transport-stimulating activity as control uteri. DNA synthetic activity in rat uterine homogenates was elevated 3-fold within 18-24 h after estradiol injection. Gel filtration showed molecular weight heterogeneity with activity eluting between 10-30 kDA. Both activities were acid and heat stable, were reduced by trypsin but not by dextran-coated charcoal. The effect of purified growth factors on DNA synthesis in primary cultures of rat uterine cells was examined. Epidermal growth factor (EGF), basic fibroblasts growth factor (bFGF), and transforming growth factor-{beta} (TGF{beta}) had no effect on {sup 3}H-thymidine incorporation.

  20. Aerobic activated sludge transformation of methotrexate: identification of biotransformation products.

    PubMed

    Kosjek, Tina; Negreira, Noelia; de Alda, Miren López; Barceló, Damià

    2015-01-01

    This study describes the biotransformation of cytostatic and immunosuppressive pharmaceutical methotrexate. Its susceptibility to microbiological breakdown was studied in a batch biotransformation system, in presence or absence of carbon source and at two activated sludge concentrations. The primary focus of the present study are methotrexate biotransformation products, which were tentatively identified by the ultra-high performance liquid chromatography-quadrupole--Orbitrap-MS. Data-dependent experiments, combining full-scan MS data with product ion spectra were acquired, in order to identify the molecular ions of methotrexate transformation products, to propose the molecular formulae and to elucidate their chemical structures. Among the identified transformation products 2,4-diamino-N10-methyl-pteroic acid is most abundant and persistent. Other biotransformation reactions involve demethylation, oxidative cleavage of amine, cleavage of C-N bond, aldehyde to carboxylate transformation and hydroxylation. Finally, a breakdown pathway is proposed, which shows that most of methotrexate breakdown products retain the diaminopteridine structural segment. In total we propose nine transformation products, among them eight are described as methotrexate transformation products for the first time. PMID:24835159

  1. Effects of transforming growth factor-beta on growth and differentiation of the continuous rat thyroid follicular cell line, FRTL-5

    SciTech Connect

    Morris, J.C. III; Ranganathan, G.; Hay, I.D.; Nelson, R.E.; Jiang, N.S.

    1988-09-01

    Transforming growth factor-beta (TGF beta) has been shown to influence the growth and differentiation of many widely varied cell types in vitro, including some that are endocrinologically active. We have investigated the previously unknown effects of this unique growth factor in the differentiated rat thyroid follicular cell line FRTL-5. The cells demonstrated specific, high affinity binding of TGF beta, and as with other epithelial cells, the growth of these thyroid follicular cells was potently inhibited by addition of TGF beta to the culture medium. TGF beta caused a significant reduction in TSH-sensitive adenylate cyclase activity in the cells. The addition of (Bu)2cAMP along with the growth factor to cultures partially reversed the characteristic morphological changes seen with TGF beta, but did not reverse the growth inhibition. To further investigate the possible mechanisms of the effects of TGF beta on the cells, we measured the influence of the growth factor on (125I)TSH binding. TGF beta did not compete for specific TSH-binding sites; however, exposure of the cells to TGF beta for 12 or more h resulted in a dose-dependent down-regulation of TSH receptors that was fully reversible. While cellular proliferation was potently inhibited by TGF beta, differentiated function, as manifest by iodine-trapping ability, was stimulated by the growth factor. This stimulation of iodine uptake was independent of, and additive to, the stimulatory effects of TSH. Finally, FRTL-5 cells in serum-free medium and in response to TSH were shown to secrete TGF beta-like activity that competed for (125I)TGF beta in a RRA. These studies suggest that TGF beta may represent an autocrine mechanism of controlling the growth response to TSH in thyroid follicular cells, while allowing the continuance of differentiated function.

  2. Quantitative assessment of growth plate activity

    SciTech Connect

    Harcke, H.T.; Macy, N.J.; Mandell, G.A.; MacEwen, G.D.

    1984-01-01

    In the immature skeleton the physis or growth plate is the area of bone least able to withstand external forces and is therefore prone to trauma. Such trauma often leads to premature closure of the plate and results in limb shortening and/or angular deformity (varus or valgus). Active localization of bone seeking tracers in the physis makes bone scintigraphy an excellent method for assessing growth plate physiology. To be most effective, however, physeal activity should be quantified so that serial evaluations are accurate and comparable. The authors have developed a quantitative method for assessing physeal activity and have applied it ot the hip and knee. Using computer acquired pinhole images of the abnormal and contralateral normal joints, ten regions of interest are placed at key locations around each joint and comparative ratios are generated to form a growth plate profile. The ratios compare segmental physeal activity to total growth plate activity on both ipsilateral and contralateral sides and to adjacent bone. In 25 patients, ages 2 to 15 years, with angular deformities of the legs secondary to trauma, Blount's disease, and Perthes disease, this technique is able to differentiate abnormal segmental physeal activity. This is important since plate closure does not usually occur uniformly across the physis. The technique may permit the use of scintigraphy in the prediction of early closure through the quantitative analysis of serial studies.

  3. Rodent p53 suppresses the transforming activity of the activated Neu oncogene by modulating the Basal promoter activity of Neu.

    PubMed

    Matin, A; Xie, Y; Kao, M; Hung, M

    1995-05-01

    The rat neu oncogene encodes a dominant transforming oncogene. The mouse wild-type p53 suppresses the transforming activity of the neu oncogene while different p53 mutants demonstrate varying ability to repress neu-induced transformation. Suppression of neu-transforming activity is due to inhibition of transcription. Deletion analysis of the rat neu promoter shows that p53 represses the basal promoter activity of neu. Therefore, rodent p53 suppresses the transforming potential of neu by inhibiting transcription from the basal promoter of neu. PMID:21556644

  4. On-line Monitoring and Active Control for Transformer Noise

    NASA Astrophysics Data System (ADS)

    Liang, Jiabi; Zhao, Tong; Tian, Chun; Wang, Xia; He, Zhenhua; Duan, Lunfeng

    This paper introduces the system for on-line monitoring and active noise control towards the transformer noise based on LabVIEW and the hardware equipment including the hardware and software. For the hardware part, it is mainly focused on the composition and the role of hardware devices, as well as the mounting location in the active noise control experiment. And the software part introduces the software flow chats, the measurement and analysis module for the sound pressure level including A, B, C weighting methods, the 1/n octave spectrum and the power spectrum, active noise control module and noise data access module.

  5. TEM Study of the Growth Mechanism, Phase Transformation, and Core/shell Structure of Semiconductor Nanowires

    NASA Astrophysics Data System (ADS)

    Wong, Tai Lun

    In this thesis, the fabrication and characterization of one-dimensional nanostructures have been studied systematically to understand the growth mechanism and structure transformation of one-dimensional nanostructures. The growth behavior of the ultrathin ZnSe nanowires with diameter less than 60 nm was found to be different from classical vapor-liquid-solid (VLS) process. The growth rate increases when the diameter of nanowires decreases, in contrast to the classical VLS process in which the growth rate increases with the diameter. The nucleation, initial growth, growth rates, defects, interface structures and growth direction of the nanowires were investigated by high resolution transmission electron microscopy (HRTEM). We found the structure and growth direction of ultra-thin nanowires are highly sensitive to growth temperatures and diameters of nanowires. At a low growth temperature (380°C), the growth direction for most nanowires is along <111>. Planar defects were found throughout the nanowires. At a high growth temperature (530°C), uniform nanowires with diameters around 10nm were grown along <110> and <112> directions, and the nanowires with diameters larger than 20nm were mainly grown along <111> direction. The possible growth mechanism of ultrathin nanowires was proposed by combining the solid catalytic growth with the interface diffusion theory, in order to explain how the growth temperature and the size of the catalysts influent the morphology, growth direction and growth rate of ultrathin nanowires. Structural and phase transformation of a nickel coated Si nanowire to NiSi2/SiC core-shell nanowire heterostructures has been investigated by the in-situ Transmission Electron Microscope (TEM). The phase transformation is a single-site nucleation process and therefore a single crystalline NiSi2 core resulted in the core-shell nanowire heterostructures. The transformation of the Si nanowire to NiSi2/SiC core-shell nanowire heterostructures was extremely

  6. Cloning the promoter for transforming growth factor-beta type III receptor. Basal and conditional expression in fetal rat osteoblasts

    NASA Technical Reports Server (NTRS)

    Ji, C.; Chen, Y.; McCarthy, T. L.; Centrella, M.

    1999-01-01

    Transforming growth factor-beta binds to three high affinity cell surface molecules that directly or indirectly regulate its biological effects. The type III receptor (TRIII) is a proteoglycan that lacks significant intracellular signaling or enzymatic motifs but may facilitate transforming growth factor-beta binding to other receptors, stabilize multimeric receptor complexes, or segregate growth factor from activating receptors. Because various agents or events that regulate osteoblast function rapidly modulate TRIII expression, we cloned the 5' region of the rat TRIII gene to assess possible control elements. DNA fragments from this region directed high reporter gene expression in osteoblasts. Sequencing showed no consensus TATA or CCAAT boxes, whereas several nuclear factors binding sequences within the 3' region of the promoter co-mapped with multiple transcription initiation sites, DNase I footprints, gel mobility shift analysis, or loss of activity by deletion or mutation. An upstream enhancer was evident 5' proximal to nucleotide -979, and a silencer region occurred between nucleotides -2014 and -2194. Glucocorticoid sensitivity mapped between nucleotides -687 and -253, whereas bone morphogenetic protein 2 sensitivity co-mapped within the silencer region. Thus, the TRIII promoter contains cooperative basal elements and dispersed growth factor- and hormone-sensitive regulatory regions that can control TRIII expression by osteoblasts.

  7. Distinct roles for mammalian target of rapamycin complexes in the fibroblast response to transforming growth factor-beta.

    PubMed

    Rahimi, Rod A; Andrianifahanana, Mahefatiana; Wilkes, Mark C; Edens, Maryanne; Kottom, Theodore J; Blenis, John; Leof, Edward B

    2009-01-01

    Transforming growth factor-beta (TGF-beta) promotes a multitude of diverse biological processes, including growth arrest of epithelial cells and proliferation of fibroblasts. Although the TGF-beta signaling pathways that promote inhibition of epithelial cell growth are well characterized, less is known about the mechanisms mediating the positive response to this growth factor. Given that TGF-beta has been shown to promote fibrotic diseases and desmoplasia, identifying the fibroblast-specific TGF-beta signaling pathways is critical. Here, we investigate the role of mammalian target of rapamycin (mTOR), a known effector of phosphatidylinositol 3-kinase (PI3K) and promoter of cell growth, in the fibroblast response to TGF-beta. We show that TGF-beta activates mTOR complex 1 (mTORC1) in fibroblasts but not epithelial cells via a PI3K-Akt-TSC2-dependent pathway. Rapamycin, the pharmacologic inhibitor of mTOR, prevents TGF-beta-mediated anchorage-independent growth without affecting TGF-beta transcriptional responses or extracellular matrix protein induction. In addition to mTORC1, we also examined the role of mTORC2 in TGF-beta action. mTORC2 promotes TGF-beta-induced morphologic transformation and is required for TGF-beta-induced Akt S473 phosphorylation but not mTORC1 activation. Interestingly, both mTOR complexes are necessary for TGF-beta-mediated growth in soft agar. These results define distinct and overlapping roles for mTORC1 and mTORC2 in the fibroblast response to TGF-beta and suggest that inhibitors of mTOR signaling may be useful in treating fibrotic processes, such as desmoplasia. PMID:19117990

  8. Calycosin inhibits migration and invasion through modulation of transforming growth factor beta-mediated mesenchymal properties in U87 and U251 cells

    PubMed Central

    Nie, Xiao-hu; Ou-yang, Jia; Xing, Ying; Li, Dan-yan; Liu, Ru-en; Xu, Ru-xiang

    2016-01-01

    In this study, we investigated the potential anticancer effects of calycosin against human glioblastoma cells, including the impacts on cell proliferation, apoptosis, and cell cycle distribution. We further studied its inhibitory activity on migration and invasion in U87 and U251 cells. Furthermore, transforming growth factor beta-mediated reductions of mesenchymal-associated genes/activators, matrix metalloproteinases-2, and -9 were detected in this process. Administration of calycosin in a glioblastoma xenograft model showed that calycosin could not only reduce tumor volume but also suppress transforming growth factor beta as well as its downstream molecules. These results revealed calycosin as a potential antitumor agent in human glioblastoma. PMID:26955262

  9. Disruption of transforming growth factor beta signaling by a novel ligand-dependent mechanism.

    PubMed

    Fernandez, Tania; Amoroso, Stephanie; Sharpe, Shellyann; Jones, Gary M; Bliskovski, Valery; Kovalchuk, Alexander; Wakefield, Lalage M; Kim, Seong-Jin; Potter, Michael; Letterio, John J

    2002-05-20

    Transforming growth factor (TGF)-beta is the prototype in a family of secreted proteins that act in autocrine and paracrine pathways to regulate cell development and function. Normal cells typically coexpress TGF-beta receptors and one or more isoforms of TGF-beta, thus the synthesis and secretion of TGF-beta as an inactive latent complex is considered an essential step in regula-ting the activity of this pathway. To determine whether intracellular activation of TGF-beta results in TGF-beta ligand-receptor interactions within the cell, we studied pristane-induced plasma cell tumors (PCTs). We now demonstrate that active TGF-beta1 in the PCT binds to intracellular TGF-beta type II receptor (TbetaRII). Disruption of the expression of TGF-beta1 by antisense TGF-beta1 mRNA restores localization of TbetaRII at the PCT cell surface, indicating a ligand-induced impediment in receptor trafficking. We also show that retroviral expression of a truncated, dominant-negative TbetaRII (dnTbetaRII) effectively competes for intracellular binding of active ligand in the PCT and restores cell surface expression of the endogenous TbetaRII. Analysis of TGF-beta receptor-activated Smad2 suggests the intracellular ligand-receptor complex is not capable of signaling. These data are the first to demonstrate the formation of an intracellular TGF-beta-receptor complex, and define a novel mechanism for modulating the TGF-beta signaling pathway. PMID:12021305

  10. Tissue localization of transforming growth factor-beta1 in pulmonary eosinophilic granuloma.

    PubMed

    Asakura, S; Colby, T V; Limper, A H

    1996-11-01

    Pulmonary eosinophilic granuloma is characterized by infiltration of the lungs with fibronodular lesions containing specialized Langerhans' cells. In some patients, progressive pulmonary fibrosis leads to significant respiratory impairment. Transforming growth factor-beta1 (TGF-beta1) promotes fibrosis by enhancing the synthesis of extracellular matrix components. The role of TGF-beta1 in promoting fibrosis in the setting of pulmonary eosinophilic granuloma is currently unknown. We used immunohistochemistry to evaluate the extent and distribution of TGF-beta1 and the extracellular matrix components type I collagen and decorin, a TGF-beta1-binding proteoglycan. Lung biopsies from 11 patients with pulmonary eosinophilic granuloma were evaluated. In biopsies with active inflammatory lesions containing Langerhans' cells, hyperplastic type 2 pneumocytes and alveolar macrophages within and surrounding the fibronodular lesions contained abundant TGF-beta1. Langerhans' cells were consistently devoid of immunoreactive TGF-beta1. Active inflammatory lesions also exhibited staining for decorin, in a loosely organized distribution. Advanced fibrotic lesions of eosinophilic granuloma, containing minimal inflammatory cells and few or no Langerhans' cells, exhibited weak or absent staining for TGF-beta1 within either hyperplastic type 2 pneumocytes or alveolar macrophages. The fibroconnective tissues of these advanced fibrotic lesions consistently revealed dense staining for decorin. Through their actions on extracellular matrix protein accumulation, TGF-beta1 and the TGF-beta1-binding proteoglycan decorin may modulate fibrotic repair accompanying pulmonary eosinophilic granuloma. PMID:8912775

  11. Requirement of HDAC6 for Transforming Growth Factor-β1-induced Epithelial-Mesenchymal Transition*

    PubMed Central

    Shan, Bin; Yao, Tso-pang; Nguyen, Hong T.; Zhuo, Ying; Levy, Dawn R.; Klingsberg, Ross C.; Tao, Hui; Palmer, Michael L.; Holder, Kevin N.; Lasky, Joseph A.

    2008-01-01

    The aberrant expression of transforming growth factor (TGF)-β1 in the tumor microenvironment and fibrotic lesions plays a critical role in tumor progression and tissue fibrosis by inducing epithelial-mesenchymal transition (EMT). EMT promotes tumor cell motility and invasiveness. How EMT affects motility and invasion is not well understood. Here we report that HDAC6 is a novel modulator of TGF-β1-induced EMT. HDAC6 is a microtubule-associated deacetylase that predominantly deacetylates nonhistone proteins, including α-tubulin, and regulates cell motility. We showed that TGF-β1-induced EMT is accompanied by HDAC6-dependent deacetylation of α-tubulin. Importantly, inhibition of HDAC6 by small interfering RNA or the small molecule inhibitor tubacin attenuated the TGF-β1-induced EMT markers, such as the aberrant expression of epithelial and mesenchymal peptides, as well as the formation of stress fibers. Reduced expression of HDAC6 also impaired the activation of SMAD3 in response to TGF-β1. Conversely, inhibition of SMAD3 activation substantially impaired HDAC6-dependent deacetylation of α-tubulin as well as the expression of EMT markers. These findings reveal a novel function of HDAC6 in EMT by intercepting the TGF-β-SMAD3 signaling cascade. Our results identify HDAC6 as a critical regulator of EMT and a potential therapeutic target against pathological EMT, a key event for tumor progression and fibrogenesis. PMID:18499657

  12. Effects of transformed ferrite growth on the tensile fracture characteristics of a dual-phase steel

    NASA Astrophysics Data System (ADS)

    Jeong, W. C.; Kim, C. H.

    1988-02-01

    The effects of transformed ferrite growth on the tensile fracture characteristics of a dual-phase steel were investigated by observing crack initiation, propagation, and fracture behaviors. Crack initiation occurred by decohesion between martensite and ferrite. However, cracks propagated along the ferrite-martensite interface in a high temperature quenched specimen, whereas in specimens quenched from lower temperature cracks propagated into the martensite particle. Tensile fracture behaviors were not strongly influenced by the cooling rate. At both cooling rates of 5.6 and 0.1 °C/sec, specimens quenched from high temperature fractured by partially brittle fracture mode, but fracture mode changed to ductile mode as the quenching temperature decreased. The effect of transformed ferrite on the fracture mode was not substantially different from that of retained ferrite. However, the crack initiation and propagation was influenced by the variation in martensite distribution caused by different growth behavior of transformed ferrite.

  13. Stable Glass Transformation to Supercooled Liquid via Surface-Initiated Growth Front

    SciTech Connect

    Swallen, Stephen F.; Traynor, Katherine; McMahon, Robert J.; Ediger, M. D.; Mates, Thomas E.

    2009-02-13

    Highly stable glasses of tris-naphthylbenzene transform into a liquid when annealed above the glass transition temperature T{sub g}. In contrast to the predictions of standard models, the observed transformation is spatially inhomogeneous. Secondary ion mass spectrometry experiments on isotopically labeled multilayer films show that the liquid grows into the stable glass with sharp growth fronts initiated at the free surface and at the interface with the substrate. For the free surface, the growth velocity is constant in time and has the same temperature dependence as self-diffusion in the equilibrium supercooled liquid. These stable glasses are packed so efficiently that surfaces and interfaces are required to initiate the transformation to the liquid even well above T{sub g}.

  14. In Vivo Modulation of T-DNA Encoded Amidohydrolase Activity in Transformed Tobacco Cells 1

    PubMed Central

    Kuleck, Gary A.; Binns, Andrew N.; Black, Robert C.

    1991-01-01

    Auxin autonomous growth of most crown gall tumor cells requires the expression of two auxin biosynthesizing genes (tms 1 and tms 2) from the T-DNA of Agrobacterium tumefaciens. The potential role of the tms 2 locus to affect auxin accumulation was studied by measuring the activity of its gene product, indoleacetamide hydrolase (AH), in cloned cells of tobacco (Nicotiana tabacum) transformed by the A6 strain of Agrobacterium tumefaciens. AH activity followed a consistent pattern over a 30 day culture cycle with a peak at 10 to 14 days. This same pattern was observed in a number of independently isolated clones as well as in uncioned tumor tissue, suggesting that AH activation is a regular process in wounded, transformed cells. Transfer of unwounded tissue to fresh media resulted in a similar pattern of AH activation, but with the peak activity only about 50 percent of the cut tissues. These results show that the tms 2 encoded AH activity is modulated over the culture cycle, and that the modulation is affected by wounding and supplying fresh nutrients in the medium. AH activity correlated closely with free indoleacetic acid levels which suggests that it can be an important determinant in controlling free IAA levels in transformed cells. PMID:16668084

  15. 14-3-3 sigma and 14-3-3 zeta plays an opposite role in cell growth inhibition mediated by transforming growth factor-beta 1.

    PubMed

    Hong, Hye-Young; Jeon, Woo-Kwang; Bae, Eun-Jin; Kim, Shin-Tae; Lee, Ho-Jae; Kim, Seong-Jin; Kim, Byung-Chul

    2010-03-01

    The expression of 14-3-3 proteins is dysregulated in various types of cancer. This study was undertaken to investigate the effects of 14-3-3 zeta and 14-3-3 sigma on cell growth inhibition mediated by transforming growth factor-beta 1 (TGF-beta1). Mouse mammary epithelial cells (Eph4) that are transformed with oncogenic c-H-Ras (EpRas) and no longer sensitive to TGF-beta1-mediated growth inhibition displayed increased expression of 14-3-3 zeta and decreased expression of 14-3-3 sigma compared with parental Eph4 cells. Using small interfering RNA-mediated knockdown and overexpression of 14-3-3 sigma or 14-3-3 zeta, we showed that 14-3-3 sigma is required for TGF-beta1-mediated growth inhibition whereas 14-3-3 zeta negatively modulates this growth inhibitory response. Notably, overexpression of 14-3-3 zeta increased the level of Smad3 protein that is phosphorylated at linker regions and cannot mediate the TGF-beta1 growth inhibitory response. Consistent with this finding, mutation of the 14-3-3 zeta phosphorylation sites in Smad3 markedly reduced the 14-3-3 zeta-mediated inhibition of TGF-beta1-induced p15 promoter-reporter activity and cell cycle arrest, suggesting that these residues are critical targets of 14-3-3 zeta in the suppression of TGF-beta1-mediated growth. Taken together, our findings indicate that dysregulation of 14-3-3 sigma or 14-3-3 zeta contributes to TGF-beta1 resistance in cancer cells. PMID:20082218

  16. An Automated Approach to Transform Use Cases into Activity Diagrams

    NASA Astrophysics Data System (ADS)

    Yue, Tao; Briand, Lionel C.; Labiche, Yvan

    Use cases are commonly used to structure and document requirements while UML activity diagrams are often used to visualize and formalize use cases, for example to support automated test case generation. Therefore the automated support for the transition from use cases to activity diagrams would provide significant, practical help. Additionally, traceability could be established through automated transformation, which could then be used for instance to relate requirements to design decisions and test cases. In this paper, we propose an approach to automatically generate activity diagrams from use cases while establishing traceability links. Data flow information can also be generated and added to these activity diagrams. Our approach is implemented in a tool, which we used to perform five case studies. The results show that high quality activity diagrams can be generated. Our analysis also shows that our approach outperforms existing academic approaches and commercial tools.

  17. Platelet-derived growth factor and transforming growth factor-beta in invertebrate immune and neuroendocrine interactions: another sign of conservation in evolution.

    PubMed

    Ottaviani, E; Franchini, A; Kletsas, D

    2001-08-01

    Growth factor-like molecules have been found in various invertebrate species. In particular, we have reported the presence of platelet-derived growth factor (PDGF)-AB and transforming growth factor-beta (TGF-beta)1 immunoreactive molecules in molluscs, insects and annelids. Moreover, PDGF-AB and TGF-beta1 affect the main immune functions, such as phagocytosis, chemotaxis and cell motility. Changes in cell shape are induced via interactions of growth factors with their respective specific receptors. The extracellular signals are transduced by the activation of classical signal transduction pathways, such as those involving PKA and PKC, and pivotal transcription regulators, i.e. the Fos, Jun and SMAD proteins. The two growth factors intervene in stress responses by activating the CRH-ACTH-biogenic amine axis. Exogenous administration of PDGF-AB and TGF-beta1 in a molluscan wound provokes an accelerated migration of immunocytes and fibroblasts to the injured area, stimulating granulation tissue formation and wound re-epithelialization. These findings suggest that these molecules are ancestral and that their function is well conserved and crucial in the maintenance of invertebrate homeostasis. PMID:11489427

  18. Phototransformation of sulfamethoxazole under simulated sunlight: Transformation products and their antibacterial activity toward Vibrio fischeri.

    PubMed

    Gmurek, M; Horn, H; Majewsky, M

    2015-12-15

    Sulfamethoxazole (SMX) is a bacteriostatic antibiotic ubiquitously found in the aquatic environment. Since conventional biological wastewater treatment is not efficient to remove SMX, photolysis in natural waters can represent an important transformation pathway. It was recently shown that SMX transformation products can retain antibiotic activity. Therefore, it is crucial to better understand photochemical processes occurring in natural water just as the formation of active transformation products (TPs). During long-term SMX photolysis experiments (one week), nine TPs were identified by reference standards. Moreover, five further TPs of photodecomposition of SMX were found. For the first time, a TP with m/z 271 [M+H](+) was observed during photolysis and tentatively confirmed as 4,x-dihydroxylated SMX. The DOC mass balance clearly showed that only around 5 to 10% were mineralized during the experiment emphasizing the need to elucidate the fate of TPs. Bacterial bioassays confirmed that the mixture retains its antibiotic toxicity toward luminescence (24h) and that there is no change over the treatment time on EC50. In contrast, growth inhibition activity was found to slightly decrease over the irradiation time. However, this decrease was not proportional to the transformation of the parent compound SMX. PMID:26298248

  19. Althaea rosea Cavanil and Plantago major L. suppress neoplastic cell transformation through the inhibition of epidermal growth factor receptor kinase.

    PubMed

    Choi, Eun-Sun; Cho, Sung-Dae; Shin, Ji-Ae; Kwon, Ki Han; Cho, Nam-Pyo; Shim, Jung-Hyun

    2012-10-01

    For thousands of years in Asia, Althaea rosea Cavanil (ARC) and Plantago major L. (PML) have been used as powerful non-toxic therapeutic agents that inhibit inflammation. However, the anticancer mechanisms and molecular targets of ARC and PML are poorly understood, particularly in epidermal growth factor (EGF)-induced neoplastic cell transformation. The aim of this study was to evaluate the chemopreventive effects and mechanisms of the methanol extracts from ARC (MARC) and PML (MPML) in EGF-induced neoplastic cell transformation of JB6 P+ mouse epidermal cells using an MTS assay, anchorage-independent cell transformation assay and western blotting. Our results showed that MARC and MPML significantly suppressed neoplastic cell transformation by inhibiting the kinase activity of the EGF receptor (EGFR). The activation of EGFR by EGF was suppressed by MARC and MPML treatment in EGFR(+/+) cells, but not in EGFR(-/-) cells. In addition, MARC and MPML inhibited EGF-induced cell proliferation in EGFR-expressing murine embryonic fibroblasts (EGFR(+/+)). These results strongly indicate that EGFR targeting by MARC and MPML may be a good strategy for chemopreventive or chemotherapeutic applications. PMID:22767187

  20. Regulation of type II transforming-growth-factor-beta receptors by protein kinase C iota.

    PubMed Central

    Chuang, Lea-Yea; Guh, Jinn-Yuh; Liu, Shu-Fen; Hung, Min-Yuan; Liao, Tung-Nan; Chiang, Tai-An; Huang, Jau-Shyang; Huang, Yu-Lun; Lin, Chi-Fong; Yang, Yu-Lin

    2003-01-01

    TGF-beta (transforming growth factor-beta) is implicated in the pathogenesis of diabetic nephropathy. We previously demonstrated that up-regulation of type II TGF-beta receptor (TbetaRII) induced by high glucose might contribute to distal tubular hypertrophy [Yang, Guh, Yang, Lai, Tsai, Hung, Chang and Chuang (1998) J. Am. Soc. Nephrol. 9, 182-193]. We have elucidated the mechanism by using cultured Madin-Darby canine kidney cells. Enhancer assay and electrophoretic-mobility-shift assay were used to estimate the involvement of transcription factors. Western blotting and an in vitro kinase assay were used to evaluate the level and activity of protein kinase. We showed that glucose (100-900 mg/dl) induced an increase in mRNA level and promoter activity of TbetaRII (note: 'mg/dl' are the units commonly used in diabetes studies). The promoter region -209 to -177 appeared to contribute to positive transactivation of TbetaRII promoter by comparing five TbetaRII-promoter-CAT (chloramphenicol acetyl-transferase) plasmids. Moreover, the transcription factor AP-1 (activator protein 1) was significantly activated and specifically binds to TbetaRII promoter (-209 to -177). More importantly, we found that atypical PKC iota might be pivotal for high glucose-induced increase in both AP-1 binding and TbetaRII promoter activity. First, high glucose induced cytosolic translocation, activation and autophosphorylation of PKC iota. Secondly, antisense PKC iota expression plasmids attenuated high-glucose-induced increase in AP-1 binding and TbetaRII promoter activity; moreover, sense PKC iota expression plasmids enhanced these instead. Finally, we showed that antisense PKC iota expression plasmids might partly attenuate a high-glucose/TGF-beta1-induced increase in fibronectin. We conclude that PKC iota might mediate high-glucose-induced increase in TbetaRII promoter activity. In addition, antisense PKC iota expression plasmid effectively suppressed up-regulation of TbetaRII and

  1. TRANSFORMATION

    SciTech Connect

    LACKS,S.A.

    2003-10-09

    Transformation, which alters the genetic makeup of an individual, is a concept that intrigues the human imagination. In Streptococcus pneumoniae such transformation was first demonstrated. Perhaps our fascination with genetics derived from our ancestors observing their own progeny, with its retention and assortment of parental traits, but such interest must have been accelerated after the dawn of agriculture. It was in pea plants that Gregor Mendel in the late 1800s examined inherited traits and found them to be determined by physical elements, or genes, passed from parents to progeny. In our day, the material basis of these genetic determinants was revealed to be DNA by the lowly bacteria, in particular, the pneumococcus. For this species, transformation by free DNA is a sexual process that enables cells to sport new combinations of genes and traits. Genetic transformation of the type found in S. pneumoniae occurs naturally in many species of bacteria (70), but, initially only a few other transformable species were found, namely, Haemophilus influenzae, Neisseria meningitides, Neisseria gonorrheae, and Bacillus subtilis (96). Natural transformation, which requires a set of genes evolved for the purpose, contrasts with artificial transformation, which is accomplished by shocking cells either electrically, as in electroporation, or by ionic and temperature shifts. Although such artificial treatments can introduce very small amounts of DNA into virtually any type of cell, the amounts introduced by natural transformation are a million-fold greater, and S. pneumoniae can take up as much as 10% of its cellular DNA content (40).

  2. Handling Arabidopsis plants: growth, preservation of seeds, transformation, and genetic crosses.

    PubMed

    Rivero, Luz; Scholl, Randy; Holomuzki, Nicholas; Crist, Deborah; Grotewold, Erich; Brkljacic, Jelena

    2014-01-01

    Growing healthy plants is essential for the advancement of Arabidopsis thaliana (Arabidopsis) research. Over the last 20 years, the Arabidopsis Biological Resource Center (ABRC) has collected and developed a series of best-practice protocols, some of which are presented in this chapter. Arabidopsis can be grown in a variety of locations, growth media, and environmental conditions. Most laboratory accessions and their mutant or transgenic derivatives flower after 4-5 weeks and set seeds after 7-8 weeks, under standard growth conditions (soil, long day, 23 ºC). Some mutant genotypes, natural accessions, and Arabidopsis relatives require strict control of growth conditions best provided by growth rooms, chambers, or incubators. Other lines can be grown in less-controlled greenhouse settings. Although the majority of lines can be grown in soil, certain experimental purposes require utilization of sterile solid or liquid growth media. These include the selection of primary transformants, identification of homozygous lethal individuals in a segregating population, or bulking of a large amount of plant material. The importance of controlling, observing, and recording growth conditions is emphasized and appropriate equipment required to perform monitoring of these conditions is listed. Proper conditions for seed harvesting and preservation, as well as seed quality control, are also described. Plant transformation and genetic crosses, two of the methods that revolutionized Arabidopsis genetics, are introduced as well. PMID:24057358

  3. Novel alleles of the transforming growth factor β-1 regulatory region and exon 1.

    PubMed

    Arrieta-Bolaños, E; Madrigal, J A; Shaw, B E

    2015-06-01

    Transforming growth factor β-1, encoded by the TGFB1 gene, is a cytokine that plays a central role in many physiologic and pathogenic processes with pleiotropic effects. Regulatory activity for this gene has been shown for 3.0 kb between positions -2665 and +423 from its translational start site. At least 17 TGFB1 regulatory region and exon 1 alleles have been defined on the basis of 18 polymorphic sites. Polymorphisms in TGFB1's regulatory region have been associated with differential levels of expression of this cytokine and to genetic risk in cancer and transplantation. In this report, we present 19 novel TGFB1 regulatory region and exon 1 alleles: p018-p036. Amplification of TGFB1's regulatory region was performed with an in-house protocol, and novel alleles were defined by either allele-specific amplification and/or molecular cloning of the amplicons, followed by sequencing in isolation. Three of these novel alleles (p018, p019, and p020) are shown to be formed by novel combinations of the aforementioned known polymorphic positions. Another 16 novel alleles are shown to carry additional known and unknown single-nucleotide polymorphisms. Polymorphism in TGFB1's regulatory region could have an impact on important processes, including embryogenesis, hematopoiesis, carcinogenesis, angiogenesis, fibrosis, immune responses, and transplantation, making its characterization necessary. PMID:25808355

  4. Targeting the Transforming Growth Factor-β Signaling Pathway in Human Cancer

    PubMed Central

    Nagaraj, Nagathihalli S

    2009-01-01

    The transforming growth factor-β (TGF-β) signaling pathway plays a pivotal role in diverse cellular processes. TGF-β switches its role from tumor suppressor in normal or dysplastic cells to a tumor promoter in advanced cancers. It is widely believed that Smad-dependent pathway is involved in TGF-β tumor suppressive functions, whereas activation of Smad-independent pathways coupled with the loss of tumor suppressor functions of TGF-β is important for its pro-oncogenic functions. TGF-β signaling has been considered as a very suitable therapeutic target. The discovery of oncogenic actions of TGF-β has generated a great deal of enthusiasm for developing TGF-β signaling inhibitors for the treatment of cancer. The challenge is to identify the group of patients where targeted tumors are not only refractory to TGF-β-induced tumor suppressor functions but also responsive to tumor promoting effects of TGF-β. TGF-β pathway inhibitors including small and large molecules have now entered clinical trials. Preclinical studies with these inhibitors have shown promise in a variety of different tumor models. Here we emphasize on the mechanisms of signaling and specific targets of the TGF-β pathway that are critical effectors of tumor progression and invasion. This report also focuses on the therapeutic intervention of TGF-β signaling in human cancers. PMID:20001556

  5. Transforming growth factor-beta 1 in experimental autoimmune neuritis. Cellular localization and time course.

    PubMed Central

    Kiefer, R.; Funa, K.; Schweitzer, T.; Jung, S.; Bourde, O.; Toyka, K. V.; Hartung, H. P.

    1996-01-01

    Experimental autoimmune neuritis (EAN) is a monophasic inflammatory disorder of the peripheral nervous system that resolves spontaneously by molecular mechanisms as yet unknown. We have investigated whether the immunosuppressive cytokine transforming growth factor-beta 1 (TGF-beta 1) might be endogenously expressed in the peripheral nervous system of Lewis rats with actively induced and adoptive transfer EAN. TGF-beta 1 mRNA was upregulated to high levels in sensory and motor roots, spinal ganglia, and sciatic nerve as revealed by quantitative Northern blot analysis and in situ hybridization histochemistry, with peak levels just preceding the first signs of clinical recovery. TGF-beta 1 mRNA was localized to scattered round cells and dense cellular infiltrates, but only rarely to Schwann cell profiles. Double labeling studies revealed macrophages and subpopulations of T cells as the major cellular source of TGF-beta 1 mRNA. TGF-beta 1 protein was visualized immunocytochemically and localized to infiltrating mononuclear cells with peak expression around the same time as mRNA, in addition to some constitutive expression in axons and Schwann cells. Our studies suggest that the spontaneous recovery observed in Lewis rat EAN might be mediated by the endogenous elaboration of TGF-beta 1 within the peripheral nerve, and that macrophages might control their own cytotoxicity by expressing TGF-beta 1. Images Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 PMID:8546208

  6. Activation of phospholipase D by growth factors and oncogenes in murine fibroblasts follow alternative but cross-talking pathways.

    PubMed Central

    del Peso, L; Lucas, L; Esteve, P; Lacal, J C

    1997-01-01

    Phospholipase D (PLD) is activated by a variety of stimuli, including mitogenic stimulation by growth factors and oncogene transformation. Activation of PLD by growth factors requires protein kinase C (PKC) since depletion of the enzyme by down-regulation or direct inhibition by specific drugs completely abrogates this effect. Transformation by the ras and src oncogenes is also associated with an increase in basal PLD activity. However, this effect is not dependent on PKC, suggesting that growth factors and oncogenes may activate PLD by two independent mechanisms. Here we demonstrate that activation of PLD by phorbol esters is greatly enhanced in ras-transformed cells, suggesting synergistic activation of PLD by ras oncogenes and PKC. Also, ras-transformed cells showed a dramatic attenuation of the PLD activation induced by growth factors, although receptor function was still detectable. This attenuation paralleled the specific uncoupling of the phosphatidylinositol-specific phospholipase C (PI-PLC) pathway, indicating that activation of PLD by growth factors may be mediated by PI-PLC and PKC activation. Attenuation of PLD activation by platelet-derived growth factor was also observed in several oncogene-transformed cells, as well as the uncoupling of the PI-PLC pathway. Neither the co-operation with PKC activation nor the attenuation of the PLD response to growth factors in ras-transformed cells was a general consequence of cell transformation, since cells transformed by other oncogenes showed a normal response to either treatment. These results support the existence of at least two alternative signalling routes for the activation of PLD, one mediated by the PI-PLC/diacylglycerol/PKC pathway and a second one mediated by several oncogenes, independent of the PKC pathway, which synergizes with the PI-PLC/PKC-dependent pathway. PMID:9065772

  7. Zoledronic acid suppresses transforming growth factor-β-induced fibrogenesis by human gingival fibroblasts

    PubMed Central

    KOMATSU, YUKO; IBI, MIHO; CHOSA, NAOYUKI; KYAKUMOTO, SEIKO; KAMO, MASAHARU; SHIBATA, TOSHIYUKI; SUGIYAMA, YOSHIKI; ISHISAKI, AKIRA

    2016-01-01

    Bisphosphonates (BPs) are analogues of pyro-phosphate that are known to prevent bone resorption by inhibiting osteoclast activity. Nitrogen-containing BPs, such as zoledronic acid (ZA), are widely used in the treatment of osteoporosis and bone metastasis. However, despite having benefits, ZA has been reported to induce BP-related osteonecrosis of the jaw (BRONJ) in cancer patients. The molecular pathological mechanisms responsible for the development of BRONJ, including necrotic bone exposure after tooth extraction, remain to be elucidated. In this study, we examined the effects of ZA on the transforming growth factor-β (TGF-β)-induced myofibroblast (MF) differentiation of human gingival fibroblasts (hGFs) and the migratory activity of hGFs, which are important for wound closure by fibrous tissue formation. The ZA maximum concentration in serum (Cmax) was found to be approximately 1.47 µM, which clinically, is found after the intravenous administration of 4 mg ZA, and ZA at this dose is considered appropriate for the treatment of cancer bone metastasis or bone diseases, such as Erdheim-Chester disease. At Cmax, ZA significantly suppressed i) the TGF-β-induced promotion of cell viability, ii) the TGF-β-induced expression of MF markers such as α-smooth muscle actin (α-SMA) and type I collagen, iii) the TGF-β-induced migratory activity of hGFs and iv) the expression level of TGF-β type I receptor on the surfaces of hGFs, as well as the TGF-β-induced phosphorylation of Smad2/3. Thus, ZA suppresses TGF-β-induced fibrous tissue formation by hGFs, possibly through the inhibition of Smad-dependent signal transduction. Our findings partly elucidate the molecular mechanisms underlying BRONJ and may prove to be beneficial to the identification of drug targets for the treatment of this symptom at the molecular level. PMID:27176567

  8. Regulation of Transforming Growth Factor-β1–driven Lung Fibrosis by Galectin-3

    PubMed Central

    MacKinnon, Alison C.; Gibbons, Michael A.; Farnworth, Sarah L.; Leffler, Hakon; Nilsson, Ulf J.; Delaine, Tamara; Simpson, A. John; Forbes, Stuart J.; Hirani, Nik; Gauldie, Jack

    2012-01-01

    Rationale: Idiopathic pulmonary fibrosis (IPF) is a chronic dysregulated response to alveolar epithelial injury with differentiation of epithelial cells and fibroblasts into matrix-secreting myofibroblasts resulting in lung scaring. The prognosis is poor and there are no effective therapies or reliable biomarkers. Galectin-3 is a β-galactoside binding lectin that is highly expressed in fibrotic tissue of diverse etiologies. Objectives: To examine the role of galectin-3 in pulmonary fibrosis. Methods: We used genetic deletion and pharmacologic inhibition in well-characterized murine models of lung fibrosis. Further mechanistic studies were performed in vitro and on samples from patients with IPF. Measurements and Main Results: Transforming growth factor (TGF)-β and bleomycin-induced lung fibrosis was dramatically reduced in mice deficient in galectin-3, manifest by reduced TGF-β1–induced EMT and myofibroblast activation and collagen production. Galectin-3 reduced phosphorylation and nuclear translocation of β-catenin but had no effect on Smad2/3 phosphorylation. A novel inhibitor of galectin-3, TD139, blocked TGF-β–induced β-catenin activation in vitro and in vivo and attenuated the late-stage progression of lung fibrosis after bleomycin. There was increased expression of galectin-3 in the bronchoalveolar lavage fluid and serum from patients with stable IPF compared with nonspecific interstitial pneumonitis and controls, which rose sharply during an acute exacerbation suggesting that galectin-3 may be a marker of active fibrosis in IPF and that strategies that block galectin-3 may be effective in treating acute fibrotic exacerbations of IPF. Conclusions: This study identifies galectin-3 as an important regulator of lung fibrosis and provides a proof of principle for galectin-3 inhibition as a potential novel therapeutic strategy for IPF. PMID:22095546

  9. Interleukin-6, vascular endothelial growth factor and transforming growth factor beta 1 in canine steroid responsive meningitis-arteritis

    PubMed Central

    2013-01-01

    Background Steroid Responsive Meningitis-Arteritis (SRMA) is a common cause of inflammation of the canine central nervous system (CNS). To investigate if transforming growth factor beta 1 (TGF-β1), interleukin-6 (IL-6) and vascular endothelial growth factor (VEGF) are involved in the production of excessive immunoglobulin A (IgA), the induction of acute phase proteins and in the development of a systemic necrotizing vasculitis, characteristic of SRMA, these three signalling proteins were evaluated. Results Cerebrospinal fluid (CSF) and serum samples of dogs during the acute phase of SRMA (SRMA) were tested for IL-6, VEGF and TGF- β1. Results were compared to those of dogs affected with SRMA during treatment (SRMA Th) and during relapse (SRMA R), to dogs with other meningoencephalomyelitides (ME), with miscellaneous non-inflammatory diseases of the CNS (CNS-Mix), with idiopathic epilepsy (IE), with systemic inflammatory diseases (Syst. Infl.) and with healthy dogs (Healthy). Concentrations of IL-6 and VEGF in CSF were significantly elevated in the SRMA group compared to the other disease categories (p < 0.05). The CSF concentrations of TGF-β1 were increased in SRMA group, but statistically significant differences were found only in comparison with Healthy and CNS-Mix groups. No differences were detected in the serum concentrations of TGF-β1 between the different groups. In untreated SRMA patients, a positive correlation (rSpear = 0.3549; P = 0.0337) between concentrations of TGF-β1 and IgA concentration was found in CSF, while concentrations of IL-6 and VEGF in CSF positively correlated with the degree of pleocytosis (rSpear = 0.8323; P < 0.0001 and rSpear = 0.5711; P = 0.0166, respectively). Conclusions Our results suggest that these three signalling proteins are biomarkers of disease activity in SRMA. VEGF might play an important role in the development of a systemic arteritis. TGF-β1 is considered to be involved in the excessive

  10. TRANSFORMER

    DOEpatents

    Baker, W.R.

    1959-08-25

    Transformers of a type adapted for use with extreme high power vacuum tubes where current requirements may be of the order of 2,000 to 200,000 amperes are described. The transformer casing has the form of a re-entrant section being extended through an opening in one end of the cylinder to form a coaxial terminal arrangement. A toroidal multi-turn primary winding is disposed within the casing in coaxial relationship therein. In a second embodiment, means are provided for forming the casing as a multi-turn secondary. The transformer is characterized by minimized resistance heating, minimized external magnetic flux, and an economical construction.

  11. The growth-inhibitory function of p53 is separable from transactivation, apoptosis and suppression of transformation by E1a and Ras.

    PubMed

    Hansen, R S; Braithwaite, A W

    1996-09-01

    p53 is known to suppress oncogenic cell transformation, inhibit cell growth, induce apoptosis and activate and repress gene transcription. To investigate the relationships between these functions, we have examined various mutant forms of p53 for their abilities to perform each activity. This study has shown that growth inhibition is not a prerequisite for apoptotic cell death as these two functions are separate and alternative activities of p53. Additionally, we have demonstrated that the ability of p53 to suppress transformation (by adenovirus E1a and activated Ras) correlates with its ability to induce apoptosis and not with its ability to inhibit cell growth. Although p53 is thought to inhibit growth through the transactivation of p21WAFI, our study has demonstrated that transcriptional activation and repression are neither sufficient nor necessary for growth inhibition. This indicates that p53 has more than one mechanism for inhibiting cell growth and that another type of biochemical function must be involved. Furthermore, we have shown that transcriptional activation and repression may each be necessary, and the combination of these activities may even be sufficient, for p53-dependent apoptosis. In summary, our results have provided new information about the cellular and biochemical mechanisms through which p53 acts as a tumor suppressor. PMID:8806689

  12. Effects of microgravity on osteoblast growth activation

    NASA Technical Reports Server (NTRS)

    Hughes-Fulford, M.; Lewis, M. L.

    1996-01-01

    Space flight is an environmental condition where astronauts can lose up to 19% of weight-bearing bone during long duration missions. We used the MC3T3-E1 osteoblast to investigate bone cell growth in microgravity (10(-6) to 10(-9)g). Osteoblasts were launched on the STS-56 shuttle flight in a quiescent state with 0.5% fetal calf serum (FCS) medium and growth activation was initiated by adding fresh medium with 10% FCS during microgravity exposure. Four days after serum activation, the cells were fixed before return to normal Earth gravity. Ground controls were treated in parallel with the flight samples in identical equipment. On landing, cell number, cell cytoskeleton, glucose utilization, and prostaglandin synthesis in flight (n = 4) and ground controls (n = 4) were examined. The flown osteoblasts grew slowly in microgravity with total cell number significantly reduced (55 +/- 6 vs 141 +/- 8 cells per microscopic field). The cytoskeleton of the flight osteoblasts had a reduced number of stress fibers and a unique abnormal morphology. Nuclei in the ground controls were large and round with punctate Hoechst staining of the DNA nucleosomes. The flight nuclei were 30% smaller than the controls (P < 0.0001) and oblong in shape, with fewer punctate areas. Due to their reduced numbers, the cells activated in microgravity used significantly less glucose than ground controls (80.2 +/- 0.7 vs 50.3 +/- 3.7 mg of glucose/dl remaining in the medium) and had reduced prostaglandin E2 (PGE2) synthesis when compared to controls (57.3 +/- 17 vs 138.3 +/- 41 pmol/ml). Cell viability was normal since, on a per-cell basis, glucose use and prostaglandin synthesis were comparable for flight and ground samples. Taken together, these data suggest that growth activation in microgravity results in reduced growth, causing reduced glucose utilization and reduced prostaglandin synthesis, with significantly altered actin cytoskeleton in osteoblasts.

  13. Transformation of the Herbicide Sulcotrione into a Root Growth Enhancer Compound by Sequential Photolysis and Hydrolysis.

    PubMed

    Goujon, Eric; Maruel, Sandra; Richard, Claire; Goupil, Pascale; Ledoigt, Gérard

    2016-01-27

    Xanthene-1,9-dione-3,4-dihydro-6-methylsulfonyl (1), the main product of sulcotrione phototransformation on plant leaves, was slowly hydrolyzed into 2-hydroxy-4-methylsulfonylbenzoic acid (2) and 1,3-cyclohexanedione (3) in aqueous solution. Interestingly, the rate of hydrolysis was significantly enhanced in the presence of roots of monocotyledonous plants, while the same treatment showed adverse effects on broadleaf weeds. Root growth enhancement varied according to the plant species and concentrations of compound 2, as shown with Zea mays roots. Compound 2 is a derivative of salicylic acid that is known to be a plant signaling messenger. Compound 2 was, therefore, able to mimic some known effects of this phytohormone. This work showed that a pesticide like sulcotrione was transformed into a compound exhibiting a positive impact on plant growth. This study exemplified a rarely reported situation where chemical and biological chain reactions transformed a xenobiotic into a compound exhibiting potential beneficial effects. PMID:26654319

  14. Mediation of wound-related Rous sarcoma virus tumorigenesis by TFG (transforming growth factor)-. beta

    SciTech Connect

    Sieweke, M.H.; Bissell, M.J. ); Thompson, N.L.; Sporn, M.B. )

    1990-06-29

    In Rous sarcoma virus (RSV)-infected chickens, wounding leads to tumor formation with nearly 100% frequency in tissues that would otherwise remain tumor-free. Identifying molecular mediators of this phenomenon should yield important clues to the mechanisms involved in RSV tumorigenesis. Immunohistochemical staining showed that TGF-{beta} is present locally shortly after wounding, but not in unwounded controls. In addition, subcutaneous administration of recombinant transforming growth factor {beta}1 (TGF-{beta}1) could substitute completely for wounding in tumor induction. A treatment protocol of four doses of 800 nanograms of TGF-{beta} resulted in v-src-expressing tumors with 100% frequency; four doses of only 10 nanograms still led to tumor formation in 80% of the animals. This effect was specific, as other growth factors with suggested roles in would healing did not elicit the same response. Epidermal growth factor (EGF) or TGF-{alpha} had no effect, and platelet-derived growth factor (PDGF) or insulin-like growth factor-1 (IGF-1) yielded only occasional tumors after longer latency. TGF-{beta} release during the would-healing response may thus be a critical event that creates a conducive environment for RSV tumorigenesis and may act as a cofactor for transformation in this system. 31 refs., 3 figs., 2 tabs.

  15. [Effects of nitrogen regulators on fertilizer nitrogen transformation in meadow cinnamon soil and on pakchoi growth].

    PubMed

    Sun, Zhi-Mei; Zhang, Kuo; Liu, Jian-Tao; Si, Huan-Sen; Wang, Yan-Qun

    2012-09-01

    Soil incubation test and pot experiment were conducted to investigate the effects of dicyandiamide (DCD) and its combination with nano-carbon on the transformation of fertilizers (urea and ammonium bicarbonate) nitrogen (N) in meadow cinnamon soil, a typical soil type in North China Plain, and on the growth of pakchoi (Brassica chinensis). In the first two weeks after applying urea and ammonium bicarbonate, the soil NH4+-N and NO3(-)-N contents varied greatly, but little variation was observed since then. The effects of the applied fertilizer N on the pakchoi growth and its N use efficiency differed significantly at early growth stages, but had little difference at harvesting stage. The DCD inhibited the transformation of the fertilizer N (especially ammonium bicarbonate N) into nitrate markedly, and this effect increased with increasing DCD dose. Under the conditions of our experiment, the optimal application rate of DCD was 1.0-1.5% of applied fertilize N, which could increase the pakchoi yield significantly, improve the leaf color, decrease the plant nitrate contents, and increase the fertilizer N use efficiency. The combination of DCD and nano-carbon exerted a synergistic effect on inhibiting soil ammonium oxidation, and also, promoted the pakchoi growth and N utilization at early growth stages significantly and decreased the plant nitrate level at harvesting stage. PMID:23286007

  16. Purines in neurite growth and astroglia activation.

    PubMed

    Heine, Claudia; Sygnecka, Katja; Franke, Heike

    2016-05-01

    The mammalian nervous system is a complex, functional network of neurons, consisting of local and long-range connections. Neuronal growth is highly coordinated by a variety of extracellular and intracellular signaling molecules. Purines turned out to be an essential component of these processes. Here, we review the current knowledge about the involvement of purinergic signaling in the regulation of neuronal development. We particularly focus on its role in neuritogenesis: the formation and extension of neurites. In the course of maturation mammals generally lose their ability to regenerate the central nervous system (CNS) e.g. after traumatic brain injury; although, spontaneous regeneration still occurs in the peripheral nervous system (PNS). Thus, it is crucial to translate the knowledge about CNS development and PNS regeneration into novel approaches to enable neurons of the mature CNS to regenerate. In this context we give a general overview of growth-inhibitory and growth-stimulatory factors and mechanisms involved in neurite growth. With regard to neuronal growth, astrocytes are an important cell population. They provide structural and metabolic support to neurons and actively participate in brain signaling. Astrocytes respond to injury with beneficial or detrimental reactions with regard to axonal growth. In this review we present the current knowledge of purines in these glial functions. Moreover, we discuss organotypic brain slice co-cultures as a model which retains neuron-glia interactions, and further presents at once a model for CNS development and regeneration. In summary, the purinergic system is a pivotal factor in neuronal development and in the response to injury. This article is part of the Special Issue entitled 'Purines in Neurodegeneration and Neuroregeneration'. PMID:26498067

  17. Increased transforming growth factor beta 1 expression mediates ozone-induced airway fibrosis in mice

    PubMed Central

    Katre, Ashwini; Ballinger, Carol; Akhter, Hasina; Fanucchi, Michelle; Kim, Dae-Kee; Postlethwait, Edward; Liu, Rui-Ming

    2013-01-01

    Ozone (O3), a commonly encountered environmental pollutant, has been shown to induce pulmonary fibrosis in different animal models; the underlying mechanism, however, remains elusive. To investigate the molecular mechanism underlying O3-induced pulmonary fibrosis, 6- to 8-week-old C57BL/6 male mice were exposed to a cyclic O3 exposure protocol consisting of 2 days of filtered air and 5 days of O3 exposure (0.5 ppm, 8 h/day) for 5 and 10 cycles with or without intraperitoneal injection of IN-1233, a specific inhibitor of the type 1 receptor of transforming growth factor beta (TGF-β), the most potent profibrogenic cytokine. The results showed that O3 exposure for 5 or 10 cycles increased the TGF-β protein level in the epithelial lining fluid (ELF), associated with an increase in the expression of plasminogen activator inhibitor 1 (PAI-1), a TGF-β-responsive gene that plays a critical role in the development of fibrosis under various pathological conditions. Cyclic O3 exposure also increased the deposition of collagens and alpha smooth muscle actin (α-SMA) in airway walls. However, these fibrotic changes were not overt until after 10 cycles of O3 exposure. Importantly, blockage of the TGF-β signaling pathway with IN-1233 suppressed O3-induced Smad2/3 phosphorylation, PAI-1 expression, as well as collagens and α-SMA deposition in the lung. Our data demonstrate for the first time that O3 exposure increases TGF-β expression and activates TGF-β signaling pathways, which mediates O3-induced lung fibrotic responses in vivo. PMID:21689010

  18. Localization of transforming growth factor-beta at the human fetal-maternal interface: role in trophoblast growth and differentiation.

    PubMed

    Graham, C H; Lysiak, J J; McCrae, K R; Lala, P K

    1992-04-01

    We examined the localization of transforming growth factor (TGF)-beta in first-trimester and term human decidua and chorionic villi and explored the role of this factor on the proliferation and differentiation of cultured trophoblast cells. Two antibodies, 1D11.16.8, a mouse monoclonal neutralizing antibody capable of recognizing both TGF-beta 1 and TGF-beta 2 and CL-B1/29, a rabbit polyclonal antibody capable of recognizing TGF-beta 2, were used to immunolocalize TGF-beta in fixed, paraffin-embedded, or fixed, frozen sections of placenta and decidua, providing similar results. Intense labeling was observed in the extracellular matrix (ECM) of the first-trimester decidua and cytoplasm of term decidual cells. Syncytiotrophoblast cell cytoplasm as well as the ECM in the core of the chorionic villi of both first-trimester and term placentas exhibited a moderate degree of labeling. Strong cytoplasmic labeling was observed in the cytotrophoblastic shell of the term placenta. To examine the role of TGF-beta on trophoblast proliferation and differentiation, early passage cultures of first-trimester and primary cultures of term trophoblast cells were established and characterized on the basis of numerous immunocytochemical and functional markers. These cells expressed cytokeratin, placental alkaline phosphatase, urokinase-type plasminogen activator, and pregnancy-specific beta glycoprotein, but not factor VIII or 63D3; they also produced hCG and collagenase type IV. Exposure of first-trimester trophoblast cultures to TGF-beta 1 significantly inhibited proliferation in a dose-dependent manner. An antiproliferative effect was also noted in the presence of TGF-beta 2. These effects were abrogated in the presence of the neutralizing anti-TGF-beta antibody (1D11.16.8) in a concentration-dependent manner. In a 3-day culture, exogenous TGF-beta 1 stimulated formation of multinucleated cells by the first trimester as well as term trophoblast cells. Addition of neutralizing anti

  19. Severe inflammatory bowel disease associated with congenital alteration of transforming growth factor beta signaling.

    PubMed

    Naviglio, Samuele; Arrigo, Serena; Martelossi, Stefano; Villanacci, Vincenzo; Tommasini, Alberto; Loganes, Claudia; Fabretto, Antonella; Vignola, Silvia; Lonardi, Silvia; Ventura, Alessandro

    2014-08-01

    Transforming growth factor beta is a pleiotropic cytokine which plays a central role in the homeostasis of the immune system. A complex dysregulation of its signaling occurs in Loeys-Dietz syndrome, a monogenic disorder caused by mutations of transforming growth factor beta receptors type 1 or type 2, characterized by skeletal involvement, craniofacial abnormalities, and arterial tortuosity with a strong predisposition for aneurysm and dissection. In addition, several immunologic abnormalities have been described in these patients, including an increased risk of allergic disorders as well as eosinophilic gastrointestinal disorders. The occurrence of inflammatory bowel disorders has been also reported, but it is poorly documented. We describe two unrelated children with Loeys-Dietz syndrome affected by severe chronic inflammatory colitis appearing at an early age. The intestinal disease presented similar features in both patients, including a histopathological picture of non-eosinophilic chronic ulcerative colitis, striking elevation of inflammatory markers, and a distinctly severe clinical course leading to failure to thrive, with resistance to multiple immunosuppressive treatments. One of the patients also presented autoimmune thyroiditis. Our report confirms that chronic ulcerative colitis may be associated with Loeys-Dietz syndrome. This finding suggests that an alteration of transforming growth factor beta signaling may by itself predispose to inflammatory colitis in humans, and represent an invaluable model to understand inflammatory bowel diseases. PMID:24486179

  20. Deletion of ocular transforming growth factor β signaling mimics essential characteristics of diabetic retinopathy.

    PubMed

    Braunger, Barbara M; Leimbeck, Sarah V; Schlecht, Anja; Volz, Cornelia; Jägle, Herbert; Tamm, Ernst R

    2015-06-01

    Diabetic retinopathy, a major cause of blindness, is characterized by a distinct phenotype. The molecular causes of the phenotype are not sufficiently clear. Here, we report that deletion of transforming growth factor β signaling in the retinal microenvironment of newborn mice induces changes that largely mimic the phenotype of nonproliferative and proliferative diabetic retinopathy in humans. Lack of transforming growth factor β signaling leads to the formation of abundant microaneurysms, leaky capillaries, and retinal hemorrhages. Retinal capillaries are not covered by differentiated pericytes, but by a coat of vascular smooth muscle-like cells and a thickened basal lamina. Reactive microglia is found in close association with retinal capillaries. In older animals, loss of endothelial cells and the formation of ghost vessels are observed, findings that correlate with the induction of angiogenic molecules and the accumulation of retinal hypoxia-inducible factor 1α, indicating hypoxia. Consequently, retinal and vitreal neovascularization occurs, a scenario that leads to retinal detachment, vitreal hemorrhages, neuronal apoptosis, and impairment of sensory function. We conclude that transforming growth factor β signaling is required for the differentiation of retinal pericytes during vascular development of the retina. Lack of differentiated pericytes initiates a scenario of structural and functional changes in the retina that mimics those of diabetic retinopathy strongly indicating a common mechanism. PMID:25857227

  1. Estrogen Receptor β Isoform-Specific Induction of Transforming Growth Factor β-Inducible Early Gene-1 in Human Osteoblast Cells: An Essential Role for the Activation Function 1 Domain

    PubMed Central

    Hawse, John R.; Subramaniam, Malayannan; Monroe, David G.; Hemmingsen, Amanda H.; Ingle, James N.; Khosla, Sundeep; Oursler, Merry Jo; Spelsberg, Thomas C.

    2008-01-01

    The estrogen receptors (ER) α and β are important ligand-mediated transcription factors known to play significant biological roles in numerous tissues including bone. Despite the high homology shared by these receptors, recent studies have suggested that their function is largely unique. Although these receptors have been studied in detail for more than a decade, little data exist concerning the mechanisms by which these two proteins regulate distinct sets of genes. Using the TGFβ-inducible early gene-1 (TIEG) as a model, we demonstrate that TIEG is rapidly induced in response to estrogen in osteoblasts by ERβ, but not ERα. We have identified the regulatory elements utilized by ERβ and have demonstrated that ERβ recruits steroid receptor coactivator (SRC)1 and SRC2 to this regulatory region. Additionally, deletion of the ERβ-activation function 1 (AF1) domain drastically decreases the estrogen induction of TIEG. Through the use of chimeric receptors, we have demonstrated that the AF1 domain of ERβ is responsible for recruiting SRC1 and SRC2 and inducing the expression of TIEG in osteoblasts. Finally, SRC1, but not SRC2, is essential for TIEG induction by ERβ. Overall, these data demonstrate that the estrogen induction of TIEG is ERβ specific and that the AF1 domain of ERβ confers this specificity. Finally, a novel and important role for ERβ’s AF1 is implicated in the recruitment of specific coactivators, suggesting that the AF1 may play a significant role in conferring the differences in regulation of gene expression by these two receptors. PMID:18483178

  2. Apurinic/apyrimidinic endonuclease 1 regulates angiogenesis in a transforming growth factor β-dependent manner in human osteosarcoma

    PubMed Central

    Jiang, Xuan; Shan, Jinlu; Dai, Nan; Zhong, Zhaoyang; Qing, Yi; Yang, Yuxing; Zhang, Shiheng; Li, Chongyi; Sui, Jiangdong; Ren, Tao; Li, Mengxia; Wang, Dong

    2015-01-01

    Angiogenesis plays an important role in tumor growth and metastasis and has been reported to be inversely correlated with overall survival of osteosarcoma patients. It has been shown that apurinic/apyrimidinic endonuclease 1 (APE1), a dually functional protein possessing both base excision repair and redox activities, is involved in tumor angiogenesis, although these mechanisms are not fully understood. Our previous study showed that the expression of transforming growth factor β (TGFβ) was significantly reduced in APE1-deficient osteosarcoma cells. Transforming growth factor β promotes cancer metastasis through various mechanisms including immunosuppression, angiogenesis, and invasion. In the current study, we initially revealed that APE1, TGFβ, and microvessel density (MVD) have pairwise correlation in osteosarcoma tissue samples, whereas TGFβ, tumor size, and MVD were inversely related to the prognosis of the cohort. We found that knocking down APE1 in osteosarcoma cells resulted in TGFβ downregulation. In addition, APE1-siRNA led to suppression of angiogenesis in vitro based on HUVECs in Transwell and Matrigel tube formation assays. Reduced secretory protein level of TGFβ of culture medium also resulted in decreased phosphorylation of Smad3 of HUVECs. In a mouse xenograft model, siRNA-mediated silencing of APE1 downregulated TGFβ expression, tumor size, and MVD. Collectively, the current evidence indicates that APE1 regulates angiogenesis in osteosarcoma by controlling the TGFβ pathway, suggesting a novel target for anti-angiogenesis therapy in human osteosarcoma. PMID:26250694

  3. Active states and structure transformations in accreting white dwarfs

    NASA Astrophysics Data System (ADS)

    Boneva, Daniela; Kaygorodov, Pavel

    2016-07-01

    Active states in white dwarfs are usually associated with light curve's effects that concern to the bursts, flickering or flare-up occurrences. It is common that a gas-dynamics source exists for each of these processes there. We consider the white dwarf binary stars with accretion disc around the primary. We suggest a flow transformation modeling of the mechanisms that are responsible for ability to cause some flow instability and bring the white dwarfs system to the outburst's development. The processes that cause the accretion rate to sufficiently increase are discussed. Then the transition from a quiescent to an active state is realized. We analyze a quasi-periodic variability in the luminosity of white dwarf binary stars systems. The results are supported with an observational data.

  4. Doppler radar fall activity detection using the wavelet transform.

    PubMed

    Su, Bo Yu; Ho, K C; Rantz, Marilyn J; Skubic, Marjorie

    2015-03-01

    We propose in this paper the use of Wavelet transform (WT) to detect human falls using a ceiling mounted Doppler range control radar. The radar senses any motions from falls as well as nonfalls due to the Doppler effect. The WT is very effective in distinguishing the falls from other activities, making it a promising technique for radar fall detection in nonobtrusive inhome elder care applications. The proposed radar fall detector consists of two stages. The prescreen stage uses the coefficients of wavelet decomposition at a given scale to identify the time locations in which fall activities may have occurred. The classification stage extracts the time-frequency content from the wavelet coefficients at many scales to form a feature vector for fall versus nonfall classification. The selection of different wavelet functions is examined to achieve better performance. Experimental results using the data from the laboratory and real inhome environments validate the promising and robust performance of the proposed detector. PMID:25376033

  5. Transforming growth factor-beta1 upregulates myostatin expression in mouse C2C12 myoblasts.

    PubMed

    Budasz-Rwiderska, M; Jank, M; Motyl, T

    2005-06-01

    Myostatin (MSTN) and transforming growth factor-beta1 (TGF-beta1) belong to the same TGF-beta superfamily of proteins. They are involved in regulation of skeletal muscle growth and development as well as muscle catabolism. The aim of the present study was to investigate the relationship between MSTN and TGF-beta1 expression in proliferating and differentiating mouse C2C12 myoblasts cultured in normal and catabolic conditions and to evaluate the effect of exogenous TGF-beta1 as well as "knock down" of TGF-beta1 receptor type II on MSTN expression in proliferating and differentiating myogenic cells. The direct effect of TGF-beta1 on myostatin was also examined. Myostatin expression increased gradually with cell confluency in proliferating cultures, while the level of TGF-beta1, detected in the form of a 100 kDa small latent complex diminished. Myostatin expression was accompanied by a partial cell cycle arrest. Three forms of myostatin were found: a 52 kDa precursor, a 40 kDa latency associated propeptide, and a 26 kDa active peptide. A decrease in myostatin and TGF-beta1 levels was observed during the first three days of differentiation, which was subsequently followed by significant increase of their expression during next three to four days of differentiation. Catabolic state induced by dexamethasone significantly increased the level of all forms of myostatin as well as latent (100 kDa) and active (25 kDa) forms of TGF-beta1 in differentiating myoblasts in a dose dependent manner. Exogenous TGF-beta1 (2 ng/ml) significantly increased myostatin levels both in proliferating and differentiating C2C12 myoblasts, whereas silencing of the TGF-beta1 receptor II gene significantly lowered myostatin level in examined cells. The presented results indicate that TGF-beta1 may control myostatin-related regulation of myogenesis through up-regulation of myostatin, predominantly in the course of terminal differentiation and glucocorticoid-dependent catabolic stimulation. PMID

  6. Transforming growth factor-alpha in vivo stimulates epithelial cell proliferation in digestive tissues of suckling rats.

    PubMed Central

    Hormi, K; Lehy, T

    1996-01-01

    BACKGROUND: The role that exogenous transforming growth factor-alpha (TGF-alpha) may exert on cell proliferation in vivo is poorly understood. AIM: To investigate the effect of rat TGF-alpha on epithelial cell proliferation in all suckling rat digestive tissues and to compare it with that of rat epidermal growth factor (EGF). ANIMAL AND METHODS: TGF-alpha and EGF were given three times daily either subcutaneously (10 or 20 micrograms/kg) or intraperitoneally (100 micrograms/kg) to rats from the ninth postnatal day. Cell proliferation was assessed through 5-bromo- 2-deoxyuridine incorporation and estimation of labelling indices. RESULTS: For both growth factors, the highest dose given for only two days significantly increased stomach and intestinal weights compared with controls (p < 0.05 to p < 0.001). The proliferative responded depended on the dose given, colonic mucosa being the most sensitive whereas oxyntic mucosa remained unresponsive. TGF-alpha was as potent as EGF in stimulating epithelial cell proliferation in antral, duodenal, and colonic mucosae. However, EGF was more active on oesophageal and jejunal cell proliferation whereas TGF-alpha was more active on pancreatic exocrine cell proliferation and the differences between the two growth factor treated groups were significant. CONCLUSIONS: These results prove for the first time the stimulating effect in vivo of exogenous rat TGF-alpha on epithelial cell proliferation in rat digestive tissues during the developmental period and support a functional role for TGF-alpha at that time. PMID:8944561

  7. Plant lectin can target receptors containing sialic acid, exemplified by podoplanin, to inhibit transformed cell growth and migration.

    PubMed

    Ochoa-Alvarez, Jhon Alberto; Krishnan, Harini; Shen, Yongquan; Acharya, Nimish K; Han, Min; McNulty, Dean E; Hasegawa, Hitoki; Hyodo, Toshinori; Senga, Takeshi; Geng, Jian-Guo; Kosciuk, Mary; Shin, Seung S; Goydos, James S; Temiakov, Dmitry; Nagele, Robert G; Goldberg, Gary S

    2012-01-01

    Cancer is a leading cause of death of men and women worldwide. Tumor cell motility contributes to metastatic invasion that causes the vast majority of cancer deaths. Extracellular receptors modified by α2,3-sialic acids that promote this motility can serve as ideal chemotherapeutic targets. For example, the extracellular domain of the mucin receptor podoplanin (PDPN) is highly O-glycosylated with α2,3-sialic acid linked to galactose. PDPN is activated by endogenous ligands to induce tumor cell motility and metastasis. Dietary lectins that target proteins containing α2,3-sialic acid inhibit tumor cell growth. However, anti-cancer lectins that have been examined thus far target receptors that have not been identified. We report here that a lectin from the seeds of Maackia amurensis (MASL) with affinity for O-linked carbohydrate chains containing sialic acid targets PDPN to inhibit transformed cell growth and motility at nanomolar concentrations. Interestingly, the biological activity of this lectin survives gastrointestinal proteolysis and enters the cardiovascular system to inhibit melanoma cell growth, migration, and tumorigenesis. These studies demonstrate how lectins may be used to help develop dietary agents that target specific receptors to combat malignant cell growth. PMID:22844530

  8. Plant Lectin Can Target Receptors Containing Sialic Acid, Exemplified by Podoplanin, to Inhibit Transformed Cell Growth and Migration

    PubMed Central

    Shen, Yongquan; Acharya, Nimish K.; Han, Min; McNulty, Dean E.; Hasegawa, Hitoki; Hyodo, Toshinori; Senga, Takeshi; Geng, Jian-Guo; Kosciuk, Mary; Shin, Seung S.; Goydos, James S.; Temiakov, Dmitry; Nagele, Robert G.; Goldberg, Gary S.

    2012-01-01

    Cancer is a leading cause of death of men and women worldwide. Tumor cell motility contributes to metastatic invasion that causes the vast majority of cancer deaths. Extracellular receptors modified by α2,3-sialic acids that promote this motility can serve as ideal chemotherapeutic targets. For example, the extracellular domain of the mucin receptor podoplanin (PDPN) is highly O-glycosylated with α2,3-sialic acid linked to galactose. PDPN is activated by endogenous ligands to induce tumor cell motility and metastasis. Dietary lectins that target proteins containing α2,3-sialic acid inhibit tumor cell growth. However, anti-cancer lectins that have been examined thus far target receptors that have not been identified. We report here that a lectin from the seeds of Maackia amurensis (MASL) with affinity for O-linked carbohydrate chains containing sialic acid targets PDPN to inhibit transformed cell growth and motility at nanomolar concentrations. Interestingly, the biological activity of this lectin survives gastrointestinal proteolysis and enters the cardiovascular system to inhibit melanoma cell growth, migration, and tumorigenesis. These studies demonstrate how lectins may be used to help develop dietary agents that target specific receptors to combat malignant cell growth. PMID:22844530

  9. Growth and Decay of Solar Active Regions

    NASA Astrophysics Data System (ADS)

    Dobias, J. J.; Chapman, G. A.; Cookson, A. M.; Preminger, D. G.; Walton, S. R.

    2002-05-01

    We report here on a study of growth and decay rates of sunspot and facular areas of solar active regions. The data used in this project come from an ongoing program of daily photometric observations of the sun with the Cartesian Full Disk Telescope No. 1 (CFDT1) at the San Fernando Observatory (SFO). Sunspot regions are determined from images taken with a red filter centered at 672.3 nm with a bandpass of 9.7 nm, while images taken with a Ca II K line filter, centered at 393.4 nm and with a bandpass of only 1nm, are used to find facular areas. Before any areas can be found on any observed images, they have to be calibrated then flattened by removing limb darkening thus producing contrast images. Sunspot areas are then determined from any pixel with contrast of -8.5% or less, while any pixel on a K line contrast image with a contrast of +4.8%/μ or higher, where μ is the cosine of the heliocentric angle, is considered to be a facular pixel. To identify the areas as clearly as possible, studied active regions were usually observed on the sun with relatively low activity; that means that each region is either alone on the sun's disk or with only very few other active regions present. Furthermore, to obtain growth and decay patterns of the areas as reliably as possible, only such active regions must be chosen for which there is as complete observational coverage as possible. At the present time studies have been finished for only a few active regions, but analysis of several others is on going. Obtained results will be presented at the meeting. This work is supported by NSF grant ATM-9912132 and NASA grants NAG5-7191 and NAG5-7778.

  10. Tumor-host interactions in the gallbladder suppress distal angiogenesis and tumor growth: involvement of transforming growth factor beta1.

    PubMed

    Gohongi, T; Fukumura, D; Boucher, Y; Yun, C O; Soff, G A; Compton, C; Todoroki, T; Jain, R K

    1999-10-01

    Angiogenesis inhibitors produced by a primary tumor can create a systemic anti-angiogenic environment and maintain metastatic tumor cells in a state of dormancy. We show here that the gallbladder microenvironment modulates the production of transforming growth factor (TGF)-beta1, a multifunctional cytokine that functions as an endogenous anti-angiogenic and anti-tumor factor in a cranial window preparation. We found that a wide variety of human gallbladder tumors express TGF-beta1 irrespective of histologic type. We implanted a gel impregnated with basic fibroblast growth factor or Mz-ChA-2 tumor in the cranial windows of mice without tumors or mice with subcutaneous or gallbladder tumors to study angiogenesis and tumor growth at a secondary site. Angiogenesis, leukocyte-endothelial interaction in vessels and tumor growth in the cranial window were substantially inhibited in mice with gallbladder tumors. The concentration of TGF-beta1 in the plasma of mice with gallbladder tumors was 300% higher than that in the plasma of mice without tumors or with subcutaneous tumors. In contrast, there was no difference in the plasma levels of other anti- and pro-angiogenic factors. Treatment with neutralizing antibody against TGF-beta1 reversed both angiogenesis suppression and inhibition of leukocyte rolling induced by gallbladder tumors. TGF-beta1 also inhibited Mz-ChA-2 tumor cell proliferation. Our results indicate that the production of anti-angiogenesis/proliferation factors is regulated by tumor-host interactions. PMID:10502827

  11. Epidermal growth factor (EGF) antagonizes transforming growth factor (TGF)-beta1-induced collagen lattice contraction by human skin fibroblasts.

    PubMed

    Park, J S; Kim, J Y; Cho, J Y; Kang, J S; Yu, Y H

    2000-12-01

    Wound contraction plays an important role in healing, but in extreme conditions, it may lead to excessive scar formation and pathological wound contracture. To date, the key regulator of excessive contracture is known to be transforming growth factor-beta (TGF-beta1). In this study, we have evaluated epidermal growth factor (EGF) antagonism in fibroblast-populated collagen lattice (FPCL) gel contraction, which has been generally used as an in vitro model thought to mimic wound contraction in vivo. As expected, TGF-beta1 treatment enhanced normal fibroblast-induced collagen gel contraction in a dose-dependent manner. In contrast, EGF did not affect normal gel formation, but significantly antagonized TGF-beta1-induced gel formation (p<0.05 at 100 ng/ml), whereas the other growth factor, platelet-derived growth factor (PDGF), did not altered either normal or TGF-beta1-induced gel contractions. Similarly, EGF treatment, but not PDGF, also significantly suppressed TGF-beta1 release that was autologously elicited by TGF-beta1 treatment (p<0.01 at 100 ng/ml). Therefore, the results suggest that EGF may negatively regulate the role of TGF-beta1 through attenuating autologous release of TGF-beta1. PMID:11145189

  12. Exercise-induced lactate accumulation regulates intramuscular triglyceride metabolism via transforming growth factor-β1 mediated pathways.

    PubMed

    Nikooie, Rohollah; Samaneh, Sajadian

    2016-01-01

    The mechanism regulating the utilization of intramuscular triacylglycerol (IMTG) during high-intensity interval training (HIIT) and post-exercise recovery period remains elusive. In this study, the acute and long-term effects of HIIT on transforming growth factor beta 1 (TGF-β1) abundance in rat skeletal muscle and role of lactate and TGF-β1 in IMTG lipolysis during post-exercise recovery period were examined. TGF-β1 and Adipose triacylglycerol lipase (ATGL) abundance as well as total lipase activity in the gastrocnemius muscle significantly increased to a maximum value 10 h after acute bout of HIIT. Inhibition of TGF-β1 signaling by intramuscular injection of SB431542 30 min prior to the acute exercise attenuated ATGL abundance and total lipase activity in the gastrocnemius muscle in response to acute exercise. Intramuscular acute injection of lactate increased TGF-β1 and ATGL abundance in the gastrocnemius muscle and there were a significant increase in Muscle TGF-β1 and ATGL abundance after 5 weeks of HIIT/lactate treatment. These results indicate that exercise-induced lactate accumulation regulates intramuscular triglyceride metabolism via transforming growth factor-β1 mediated pathways during post-exercise recovery from strenuous exercise. PMID:26522131

  13. Enhanced transformation of tetrabromobisphenol a by nitrifiers in nitrifying activated sludge.

    PubMed

    Li, Fangjie; Jiang, Bingqi; Nastold, Peter; Kolvenbach, Boris Alexander; Chen, Jianqiu; Wang, Lianhong; Guo, Hongyan; Corvini, Philippe François-Xavier; Ji, Rong

    2015-04-01

    The fate of the most commonly used brominated flame retardant, tetrabromobisphenol A (TBBPA), in wastewater treatment plants is obscure. Using a (14)C-tracer, we studied TBBPA transformation in nitrifying activated sludge (NAS). During the 31-day incubation, TBBPA transformation (half-life 10.3 days) was accompanied by mineralization (17% of initial TBBPA). Twelve metabolites, including those with single benzene ring, O-methyl TBBPA ether, and nitro compounds, were identified. When allylthiourea was added to the sludge to completely inhibit nitrification, TBBPA transformation was significantly reduced (half-life 28.9 days), formation of the polar and single-ring metabolites stopped, but O-methylation was not significantly affected. Abiotic experiments confirmed the generation of mono- and dinitro-brominated forms of bisphenol A in NAS by the abiotic nitration of TBBPA by nitrite, a product of ammonia-oxidizing microorganisms (AOMs). Three biotic (type II ipso-substitution, oxidative skeletal cleavage, and O-methylation) and one abiotic (nitro-debromination) pathways were proposed for TBBPA transformation in NAS. Apart from O-methylation, AOMs were involved in three other pathways. Our results are the first to provide information about the complex metabolism of TBBPA in NAS, and they are consistent with a determining role for nitrifiers in TBBPA degradation by initiating its cleavage into single-ring metabolites that are substrates for the growth of heterotrophic bacteria. PMID:25754048

  14. Equivalency of endothelial cell growth supplement to irradiated feeder cells in carcinogen-induced morphologic transformation of Syrian hamster embryo cells

    SciTech Connect

    Evans, C.H.; DiPaolo, J.A.

    1982-01-01

    Endothelial cell growth supplement (ECGS), an extract of bovine neural tissue with growth-promoting properties for human endothelial and epithelial cells and for mouse BALB/c fibroblast-like cells, can be substituted for feeder cells in a quantitative 7-day Syrian hamster embryo cell colony in vitro model of carcinogenesis. Inclusion of 50 or 100 micrograms ECGS/ml medium throughout the 7-day growth period produced results equal to those obtained with feeder cells. The frequency and morphology of normal fibroblast colonies and carcinogen-induced morphologically transformed cell colony growth in the presence of ECGS were similar to those in the presence of feeder cells. A positive dose-response relationship in transformation by benzo(a)pyrene occurred. The frequency of transformed colonies following UV irradiation and treatment of the cells with the cocarcinogenic tumor promoter 12-O-tetradecanoylphorbol 13-acetate was greatly augmented, and lymphotoxin, a lymphokine with anticarcinogenic activity, reduced transformation. Thus ECGS can substitute for feeder cells in supporting in vitro transformation and eliminates a potential complex source of variability for studies where interaction(s) with feeder cells are a consideration. The mechanics of this model system was simplified, and its versatility for the study of physiologic, carcinogenic, and other pathophysiologic processes was broadened.

  15. Increased origin activity in transformed versus normal cells: identification of novel protein players involved in DNA replication and cellular transformation

    PubMed Central

    Di Paola, Domenic; Rampakakis, Emmanouil; Chan, Man Kid; Arvanitis, Dina N.; Zannis-Hadjopoulos, Maria

    2010-01-01

    Using libraries of replication origins generated previously, we identified three clones that supported the autonomous replication of their respective plasmids in transformed, but not in normal cells. Assessment of their in vivo replication activity by in situ chromosomal DNA replication assays revealed that the chromosomal loci corresponding to these clones coincided with chromosomal replication origins in all cell lines, which were more active by 2–3-fold in the transformed by comparison to the normal cells. Evaluation of pre-replication complex (pre-RC) protein abundance at these origins in transformed and normal cells by chromatin immunoprecipitation assays, using anti-ORC2, -cdc6 and -cdt1 antibodies, showed that they were bound by these pre-RC proteins in all cell lines, but a 2–3-fold higher abundance was observed in the transformed by comparison to the normal cells. Electrophoretic mobility shift assays (EMSAs) performed on the most efficiently replicating clone, using nuclear extracts from the transformed and normal cells, revealed the presence of a DNA replication complex in transformed cells, which was barely detectable in normal cells. Subsequent supershift EMSAs suggested the presence of transformation-specific complexes. Mass spectrometric analysis of these complexes revealed potential new protein players involved in DNA replication that appear to correlate with cellular transformation. PMID:20064876

  16. Transforming activities of Chlamydia pneumoniae in human mesothelial cells.

    PubMed

    Rizzo, Antonietta; Carratelli, Caterina Romano; De Filippis, Anna; Bevilacqua, Nazario; Tufano, Maria Antonietta; Buommino, Elisabetta

    2014-12-01

    Knowledge in viral oncology has made considerable progress in the field of cancer fight. However, the role of bacteria as mediators of oncogenesis has not yet been elucidated. As cancer still is the leading cause of death in developed countries, understanding the long-term effects of bacteria has become of great importance as a possible means of cancer prevention. This study reports that Chlamydia pneumoniae infection induces transformation of human mesothelial cells. Mes1 cells infected with C. pneumoniae at a multiplicity of infection of 4 inclusion-forming units/cell showed many intracellular inclusion bodies. After a 7-day infection an increased proliferative activity was also observed. Real-time PCR analysis revealed a strong induction of calretinin, Wilms' tumour gene 1, osteopontin, matrix metalloproteinases-2, and membrane-type 1 metalloproteinases gene expression in Mes1 cell, infected for a longer period (14 days). The results were confirmed by western blot analysis. Zymography analysis showed that C. pneumoniae modulated the in-vitro secretion of MMP-2 in Mes1 cells both at 7 and 14 days. Cell invasion, as measured by matrigel-coated filter, increased after 7 and 14 days infection with C. pneumoniae, compared with uninfected Mes1 cells. The results of this study suggest that C. pneumoniae infection might support cellular transformation, thus increasing lung cancer risk. PMID:26421735

  17. Protein kinase A modulates transforming growth factor-β signaling through a direct interaction with Smad4 protein.

    PubMed

    Yang, Huibin; Li, Gangyong; Wu, Jing-Jiang; Wang, Lidong; Uhler, Michael; Simeone, Diane M

    2013-03-22

    Transforming growth factor β (TGFβ) signaling normally functions to regulate embryonic development and cellular homeostasis. It is increasingly recognized that TGFβ signaling is regulated by cross-talk with other signaling pathways. We previously reported that TGFβ activates protein kinase A (PKA) independent of cAMP through an interaction of an activated Smad3-Smad4 complex and the regulatory subunit of the PKA holoenzyme (PKA-R). Here we define the interaction domains of Smad4 and PKA-R and the functional consequences of this interaction. Using a series of Smad4 and PKA-R truncation mutants, we identified amino acids 290-300 of the Smad4 linker region as critical for the specific interaction of Smad4 and PKA-R. Co-immunoprecipitation assays showed that the B cAMP binding domain of PKA-R was sufficient for interaction with Smad4. Targeting of B domain regions conserved among all PKA-R isoforms and exposed on the molecular surface demonstrated that amino acids 281-285 and 320-329 were required for complex formation with Smad4. Interactions of these specific regions of Smad4 and PKA-R were necessary for TGFβ-mediated increases in PKA activity, CREB (cAMP-response element-binding protein) phosphorylation, induction of p21, and growth inhibition. Moreover, this Smad4-PKA interaction was required for TGFβ-induced epithelial mesenchymal transition, invasion of pancreatic tumor cells, and regulation of tumor growth in vivo. PMID:23362281

  18. Cellular localization of transforming growth factor-beta expression in bleomycin-induced pulmonary fibrosis.

    PubMed Central

    Zhang, K.; Flanders, K. C.; Phan, S. H.

    1995-01-01

    Bleomycin-induced pulmonary fibrosis is associated with increased lung transforming growth factor-beta (TGF-beta) gene expression, but cellular localization of the source of this expression has not been unequivocally established. In this study, lung fibrosis was induced in rats by endotracheal bleomycin injection on day 0 and, on selected days afterwards, lungs were harvested for in situ hybridization, immunohistochemical and histochemical analyses for TGF-beta 1 mRNA and protein expression, and cell identification. The results show that control lungs express essentially no detectable TGF-beta 1 mRNA or protein in the parenchyma. Before day 3 after bleomycin treatment, scattered bronchiolar epithelial cells, mononuclear cells, and eosinophils expressed elevated levels of TGF-beta 1. Between days 3 and 14, there was a major increase in the number of eosinophils, myofibroblasts, and fibroblasts strongly expressing TGF-beta 1 mRNA and protein. TGF-beta 1-producing cells were predominantly localized within areas of injury and active fibrosis. After day 14, the intensity and number of TGF-beta 1-expressing cells significantly declined and were predominantly found in fibroblasts in fibrotic areas. The expression of TGF-beta 1 protein was generally coincident with that for mRNA with the exception of bronchiolar epithelial cells in which strong protein expression was unaccompanied by a commensurate increase in mRNA. The study demonstrates that myofibroblasts, fibroblasts, and eosinophils represent the major sources of increased lung TGF-beta 1 expression in this model of pulmonary fibrosis. Images Figure 2 Figure 3 Figure 4 PMID:7543734

  19. Early defect of transforming growth factor β1 formation in Huntington’s disease

    PubMed Central

    Battaglia, Giuseppe; Cannella, Milena; Riozzi, Barbara; Orobello, Sara; Maat-Schieman, Marion L; Aronica, Eleonora; Busceti, Carla Letizia; Ciarmiello, Andrea; Alberti, Silvia; Amico, Enrico; Sassone, Jenny; Sipione, Simonetta; Bruno, Valeria; Frati, Luigi; Nicoletti, Ferdinando; Squitieri, Ferdinando

    2011-01-01

    Abstract A defective expression or activity of neurotrophic factors, such as brain- and glial-derived neurotrophic factors, contributes to neuronal damage in Huntington’s disease (HD). Here, we focused on transforming growth factor-β (TGF-β1), a pleiotropic cytokine with an established role in mechanisms of neuroprotection. Asymptomatic HD patients showed a reduction in TGF-β1 levels in the peripheral blood, which was related to trinucleotide mutation length and glucose hypometabolism in the caudate nucleus. Immunohistochemical analysis in post-mortem brain tissues showed that TGF-β1 was reduced in cortical neurons of asymptomatic and symptomatic HD patients. Both YAC128 and R6/2 HD mutant mice showed a reduced expression of TGF-β1 in the cerebral cortex, localized in neurons, but not in astrocytes. We examined the pharmacological regulation of TGF-β1 formation in asymptomatic R6/2 mice, where blood TGF-β1 levels were also reduced. In these R6/2 mice, both the mGlu2/3 metabotropic glutamate receptor agonist, LY379268, and riluzole failed to increase TGF-β1 formation in the cerebral cortex and corpus striatum, suggesting that a defect in the regulation of TGF-β1 production is associated with HD. Accordingly, reduced TGF-β1 mRNA and protein levels were found in cultured astrocytes transfected with mutated exon 1 of the human huntingtin gene, and in striatal knock-in cell lines expressing full-length huntingtin with an expanded glutamine repeat. Taken together, our data suggest that serum TGF-β1 levels are potential biomarkers of HD development during the asymptomatic phase of the disease, and raise the possibility that strategies aimed at rescuing TGF-β1 levels in the brain may influence the progression of HD. PMID:20082658

  20. Transforming growth factor-β and atherosclerosis: interwoven atherogenic and atheroprotective aspects

    PubMed Central

    Toma, Ian

    2016-01-01

    Age-related progression of cardiovascular disease is by far the largest health problem in the US and involves vascular damage, progressive vascular fibrosis and the accumulation of lipid-rich atherosclerotic lesions. Advanced lesions can restrict flow to key organs and can trigger occlusive thrombosis resulting in a stroke or myocardial infarction. Transforming growth factor-beta (TGF-β) is a major orchestrator of the fibroproliferative response to tissue damage. In the early stages of repair, TGF-β is released from platelets and activated from matrix reservoirs; it then stimulates the chemotaxis of repair cells, modulates immunity and inflammation and induces matrix production. At later stages, it negatively regulates fibrosis through its strong antiproliferative and apoptotic effects on fibrotic cells. In advanced lesions, TGF-β might be important in arterial calcification, commonly referred to as “hardening of the arteries”. Because TGF-β can signal through multiple pathways, namely the SMADs, a MAPK pathway and the Rho/ROCK pathways, selective defects in TGF-β signaling can disrupt otherwise coordinated pathways of tissue regeneration. TGF-β is known to control cell proliferation, cell migration, matrix synthesis, wound contraction, calcification and the immune response, all being major components of the atherosclerotic process. However, many of the effects of TGF-β are essential to normal tissue repair and thus, TGF-β is often thought to be “atheroprotective”. The present review attempts to parse systematically the known effects of TGF-β on both the major risk factors for atherosclerosis and to isolate the role of TGF-β in the many component pathways involved in atherogenesis. PMID:21626289

  1. Transcriptional pathways associated with the slow growth phenotype of transformed Anaplasma marginale

    PubMed Central

    2013-01-01

    Background The ability to genetically manipulate bacteria has been fundamentally important for both basic biological discovery and translational research to develop new vaccines and antibiotics. Experimental alteration of the genetic content of prokaryotic pathogens has revealed both expected functional relationships and unexpected phenotypic consequences. Slow growth phenotypes have been reported for multiple transformed bacterial species, including extracellular and intracellular pathogens. Understanding the genes and pathways responsible for the slow growth phenotype provides the opportunity to develop attenuated vaccines as well as bacteriostatic antibiotics. Transformed Anaplasma marginale, a rickettsial pathogen, exhibits slow growth in vitro and in vivo as compared to the parent wild type strain, providing the opportunity to identify the underlying genes and pathways associated with this phenotype. Results Whole genome transcriptional profiling allowed for identification of specific genes and pathways altered in transformed A. marginale. Genes found immediately upstream and downstream of the insertion site, including a four gene operon encoding key outer membrane proteins, were not differentially transcribed between wild type and transformed A. marginale. This lack of significant difference in transcription of flanking genes and the large size of the insert relative to the genome were consistent with a trans rather than a cis effect. Transcriptional profiling across the complete genome identified the most differentially transcribed genes, including an iron transporter, an RNA cleaving enzyme and several genes involved in translation. In order to confirm the trend seen in translation-related genes, K-means clustering and Gene Set Enrichment Analysis (GSEA) were applied. These algorithms allowed evaluation of the behavior of genes as groups that share transcriptional status or biological function. Clustering and GSEA confirmed the initial observations and

  2. Transforming growth factor β recruits persistent MAPK signaling to regulate long-term memory consolidation in Aplysia californica.

    PubMed

    Shobe, Justin; Philips, Gary T; Carew, Thomas J

    2016-05-01

    In this study, we explore the mechanistic relationship between growth factor signaling and kinase activity that supports the protein synthesis-dependent phase of long-term memory (LTM) consolidation for sensitization ofAplysia Specifically, we examine LTM for tail shock-induced sensitization of the tail-elicited siphon withdrawal (T-SW) reflex, a form of memory that requires both (i) extracellular signal-regulated kinase (ERK1/2; MAPK) activity within identified sensory neurons (SNs) that mediate the T-SW and (ii) the activation of transforming growth factor β (TGFβ) signaling. We now report that repeated tail shocks that induce intermediate-term (ITM) and LTM for sensitization, also induce a sustained post-training phase of MAPK activity in SNs (lasting at least 1 h). We identified two mechanistically distinct phases of post-training MAPK: (i) an immediate phase that does not require ongoing protein synthesis or TGFβ signaling, and (ii) a sustained phase that requires both protein synthesis and extracellular TGFβ signaling. We find that LTM consolidation requires sustained MAPK, and is disrupted by inhibitors of protein synthesis and TGFβ signaling during the consolidation window. These results provide strong evidence that TGFβ signaling sustains MAPK activity as an essential mechanistic step for LTM consolidation. PMID:27084925

  3. Shape and size transformation of gold nanorods (GNRs) via oxidation process: A reverse growth mechanism

    NASA Astrophysics Data System (ADS)

    Chandrasekar, Govindasamy; Mougin, Karine; Haidara, Hamidou; Vidal, Loïc; Gnecco, Enrico

    2011-02-01

    The anisotropic shape transformation of gold nanorods (GNRs) with H2O2 was observed in the presence of "cethyl trimethylammonium bromide" (CTAB). The adequate oxidative dissolution of GNR is provided by the following autocatalytic scheme with H2O2: Au0 → Au+, Au0 + Aun+ → 2Au3+, n = 1 and 3. The shape transformation of the GNRs was investigated by UV-vis spectroscopy and transmission electron microscopy (TEM). As-synthesised GNRs exhibit transverse plasmon band (TPB) at 523 nm and longitudinal plasmon band (LPB) at 731 nm. Upon H2O2 oxidation, the LPB showed a systematic hypsochromic (blue) shift, while TPB stays at ca. 523 nm. In addition, a new emerging peak observed at ca. 390 nm due to Au(III)-CTAB complex formation during the oxidation. TEM analysis of as-synthesised GNRs with H2O2 confirmed the shape transformation to spherical particles with 10 nm size in 2 h, whereas centrifuged nanorod solution showed no changes in the aspect ratio under the same condition. Au3+ ions produced from oxidation, complex with excess free CTAB and approach the nanorods preferentially at the end, leading to spatially directed oxidation. This work provides some information to the crystal stability and the growth mechanism of GNRs, as both growth and shortening reactions occur preferentially at the edge of single-crystalline GNRs, all directed by Br- ions.

  4. Phenol oxidase activity in secondary transformed peat-moorsh soils

    NASA Astrophysics Data System (ADS)

    Styła, K.; Szajdak, L.

    2009-04-01

    The chemical composition of peat depends on the geobotanical conditions of its formation and on the depth of sampling. The evolution of hydrogenic peat soils is closely related to the genesis of peat and to the changes in water conditions. Due to a number of factors including oscillation of ground water level, different redox potential, changes of aerobic conditions, different plant communities, and root exudes, and products of the degradation of plant remains, peat-moorsh soils may undergo a process of secondary transformation conditions (Sokolowska et al. 2005; Szajdak et al. 2007). Phenol oxidase is one of the few enzymes able to degrade recalcitrant phenolic materials as lignin (Freeman et al. 2004). Phenol oxidase enzymes catalyze polyphenol oxidation in the presence of oxygen (O2) by removing phenolic hydrogen or hydrogenes to from radicals or quinines. These products undergo nucleophilic addition reactions in the presence or absence of free - NH2 group with the eventual production of humic acid-like polymers. The presence of phenol oxidase in soil environments is important in the formation of humic substances a desirable process because the carbon is stored in a stable form (Matocha et al. 2004). The investigations were carried out on the transect of peatland 4.5 km long, located in the Agroecological Landscape Park host D. Chlapowski in Turew (40 km South-West of Poznań, West Polish Lowland). The sites of investigation were located along Wyskoć ditch. The following material was taken from four chosen sites marked as Zbechy, Bridge, Shelterbelt and Hirudo in two layers: cartel (0-50cm) and cattle (50-100cm). The object of this study was to characterize the biochemical properties by the determination of the phenol oxidize activity in two layers of the four different peat-moors soils used as meadow. The phenol oxidase activity was determined spectrophotometrically by measuring quinone formation at λmax=525 nm with catechol as substrate by method of Perucci

  5. Zoledronic acid suppresses transforming growth factor-β-induced fibrogenesis by human gingival fibroblasts.

    PubMed

    Komatsu, Yuko; Ibi, Miho; Chosa, Naoyuki; Kyakumoto, Seiko; Kamo, Masaharu; Shibata, Toshiyuki; Sugiyama, Yoshiki; Ishisaki, Akira

    2016-07-01

    Bisphosphonates (BPs) are analogues of pyrophosphate that are known to prevent bone resorption by inhibiting osteoclast activity. Nitrogen-containing BPs, such as zoledronic acid (ZA), are widely used in the treatment of osteoporosis and bone metastasis. However, despite having benefits, ZA has been reported to induce BP-related osteonecrosis of the jaw (BRONJ) in cancer patients. The molecular pathological mechanisms responsible for the development of BRONJ, including necrotic bone exposure after tooth extraction, remain to be elucidated. In this study, we examined the effects of ZA on the transforming growth factor-β (TGF‑β)-induced myofibroblast (MF) differentiation of human gingival fibroblasts (hGFs) and the migratory activity of hGFs, which are important for wound closure by fibrous tissue formation. The ZA maximum concentration in serum (Cmax) was found to be approximately 1.47 µM, which clinically, is found after the intravenous administration of 4 mg ZA, and ZA at this dose is considered appropriate for the treatment of cancer bone metastasis or bone diseases, such as Erdheim-Chester disease. At Cmax, ZA significantly suppressed i) the TGF‑β-induced promotion of cell viability, ii) the TGF‑β-induced expression of MF markers such as α-smooth muscle actin (α-SMA) and type I collagen, iii) the TGF‑β-induced migratory activity of hGFs and iv) the expression level of TGF‑β type I receptor on the surfaces of hGFs, as well as the TGF‑β-induced phosphorylation of Smad2/3. Thus, ZA suppresses TGF‑β-induced fibrous tissue formation by hGFs, possibly through the inhibition of Smad‑dependent signal transduction. Our findings partly elucidate the molecular mechanisms underlying BRONJ and may prove to be beneficial to the identification of drug targets for the treatment of this symptom at the molecular level. PMID:27176567

  6. The farnesyltransferase inhibitor, LB42708, inhibits growth and induces apoptosis irreversibly in H-ras and K-ras-transformed rat intestinal epithelial cells

    SciTech Connect

    Kim, Han-Soo; Kim, Ju Won; Gang, Jingu; Wen, Jing; Koh, Sang Seok; Koh, Jong Sung; Chung, Hyun-Ho; Song, Si Young . E-mail: gisong@yumc.yonsei.ac.kr

    2006-09-15

    LB42708 (LB7) and LB42908 (LB9) are pyrrole-based orally active farnesyltransferase inhibitors (FTIs) that have similar structures. The in vitro potencies of these compounds against FTase and GGTase I are remarkably similar, and yet they display different activity in apoptosis induction and morphological reversion of ras-transformed rat intestinal epithelial (RIE) cells. Both FTIs induced cell death despite K-ras prenylation, implying the participation of Ras-independent mechanism(s). Growth inhibition by these two FTIs was accompanied by G1 and G2/M cell cycle arrests in H-ras and K-ras-transformed RIE cells, respectively. We identified three key markers, p21{sup CIP1/WAF1}, RhoB and EGFR, that can explain the differences in the molecular mechanism of action between two FTIs. Only LB7 induced the upregulation of p21{sup CIP1/WAF1} and RhoB above the basal level that led to the cell cycle arrest and to distinct morphological alterations of ras-transformed RIE cells. Both FTIs successfully inhibited the ERK and activated JNK in RIE/K-ras cells. While the addition of conditioned medium from RIE/K-ras reversed the growth inhibition of ras-transformed RIE cells by LB9, it failed to overcome the growth inhibitory effect of LB7 in both H-ras- and K-ras-transformed RIE cells. We found that LB7, but not LB9, decreased the expression of EGFRs that confers the cellular unresponsiveness to EGFR ligands. These results suggest that LB7 causes the induction of p21{sup CIP1/WAF1} and RhoB and downregulation of EGFR that may serve as critical steps in the mechanism by which FTIs trigger irreversible inhibitions on the cell growth and apoptosis in ras-transformed cells.

  7. Mammalian dwarfins are phosphorylated in response to transforming growth factor beta and are implicated in control of cell growth.

    PubMed Central

    Yingling, J M; Das, P; Savage, C; Zhang, M; Padgett, R W; Wang, X F

    1996-01-01

    The dwarfin protein family has been genetically implicated in transforming growth factor beta (TGF-beta)-like signaling pathways in Drosophila and Caenorhabditis elegans. To investigate the role of these proteins in mammalian signaling pathways, we have isolated and studied two murine dwarfins, dwarfin-A and dwarfin-C. Using antibodies against dwarfin-A and dwarfin-C, we show that these two dwarfins and an immunogenically related protein, presumably also a dwarfin, are phosphorylated in a time- and dose-dependent manner in response to TGF-beta. Bone morphogenetic protein 2, a TGF-beta superfamily ligand, induces phosphorylation of only the related dwarfin protein. Thus, TGF-beta superfamily members may use overlapping yet distinct dwarfins to mediate their intracellular signals. Furthermore, transient overexpression of either dwarfin-A or dwarfin-C causes growth arrest, implicating the dwarfins in growth regulation. This work provides strong biochemical and preliminary functional evidence that dwarfin-A and dwarfin-C represent prototypic members of a family of mammalian proteins that may serve as mediators of signaling pathways for TGF-beta superfamily members. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 PMID:8799132

  8. Expression of transforming growth factor alpha and epidermal growth factor receptor in rat lung neoplasms induced by plutonium-239

    SciTech Connect

    Stegelmeier, B.L.; Gillett, N.A.; Hahn, F.F.; Kelly, G.; Rebar, A.H.

    1994-11-01

    Ninety-two rat lung proliferative lesions and neoplasms induced by inhaled {sup 239}PuO{sub 2} were evaluated for aberrant expression of transforming growth factor alpha (TGF-{alpha}) and epidermal growth factor receptor (EGFR). Expression of TGF-{alpha} protein, measured by immunohistochemistry, was higher in 94% of the squamous cell carcinomas and 87% of the foci of alveolar epithelial squamous metaplasia than that exhibited by the normal-appearing, adjacent lung parenchyma. In contrast, only 20% of adenocarcinomas and foci of epithelial hyperplasia expressed elevated levels of TGF-{alpha}. Many neoplasms expressing TGF-{alpha} also expressed excessive levels of EGFR mRNA. Southern and DNA slot blot analyses showed that the elevated EGFR expression was not due to amplification of the EGFR gene. These data suggest that increased amounts of TGF-{alpha} were early alterations in the progression of plutonium-induced squamous cell carcinoma, and these increases may occur in parallel with overexpression of the receptor for this growth factor. Together, these alterations create a potential autocrine loop for sustaining clonal expansion of cells initiated by high-LET radiation. 44 refs., 4 figs., 1 tab.

  9. A glycosylation-deficient endothelial cell mutant with modified responses to transforming growth factor-beta and other growth inhibitory cytokines: evidence for multiple growth inhibitory signal transduction pathways.

    PubMed Central

    Fafeur, V; O'Hara, B; Böhlen, P

    1993-01-01

    An endothelial cell line (M40) resistant to growth inhibition by transforming growth factor-beta type 1 (TGF beta 1) was isolated by chemical mutagenesis and growth in the presence of TGF beta 1. Like normal endothelial cells, this mutant is characterized by high expression of type II TGF beta receptor and low expression of type I TGF beta receptor. However, the mutant cells display a type II TGF beta receptor of reduced molecular weight as a result of a general defect in N-glycosylation of proteins. The alteration does not impair TGF beta 1 binding to cell surface receptors or the ability of TGF beta 1 to induce fibronectin or plasminogen activator inhibitor-type I production. M40 cells were also resistant to growth inhibition by tumor necrosis factor alpha (TNF alpha) and interleukin-1 alpha (IL-1 alpha) but were inhibited by interferon-gamma (IFN gamma) and heparin. These results imply that TGF beta 1, TNF alpha, and IL-1 alpha act through signal transducing pathways that are separate from pathways for IFN gamma and heparin. Basic fibroblast growth factor was still mitogenic for M40, further suggesting that TGF beta 1, TNF alpha, and IL-1 alpha act by direct inhibition of cell growth rather than by interfering with growth stimulatory pathways. Images PMID:8382975

  10. Transformation Pathways of the Recalcitrant Pharmaceutical Compound Carbamazepine by the White-Rot Fungus Pleurotus ostreatus: Effects of Growth Conditions.

    PubMed

    Golan-Rozen, Naama; Seiwert, Bettina; Riemenschneider, Christina; Reemtsma, Thorsten; Chefetz, Benny; Hadar, Yitzhak

    2015-10-20

    The widely used anticonvulsant pharmaceutical carbamazepine is recalcitrant in many environmental niches and thus poses a challenge in wastewater treatment. We followed the decomposition of carbamazepine by the white-rot fungus Pleurotus ostreatus in liquid culture compared to solid-state fermentation on lignocellulosic substrate where different enzymatic systems are active. Carbamazepine metabolites were identified using liquid chromatography-high-resolution mass spectrometry (LC-Q-TOF-MS). In liquid culture, carbamazepine was only transformed to 10,11-epoxy carbamazepine and 10,11-dihydroxy carbamazepine as a dead-end product. During solid-state fermentation, carbamazepine metabolism resulted in the generation of an additional 22 transformation products, some of which are toxic. Under solid-state-fermentation conditions, 10,11-epoxy carbamazepine was further metabolized via acridine and 10,11-dihydroxy carbamazepine pathways. The latter was further metabolized via five subpathways. When (14)C-carbonyl-labeled carbamazepine was used as the substrate, (14)C-CO2 release amounted to 17.4% of the initial radioactivity after 63 days of incubation. The proposed pathways were validated using metabolites (10,11-epoxy carbamazepine, 10,11-dihydroxy carbamazepine, and acridine) as primary substrates and following their fate at different time points. This work highlights the effect of growth conditions on the transformation pathways of xenobiotics. A better understanding of the fate of pollutants during bioremediation treatments is important for establishment of such technologies. PMID:26418858

  11. Expression of transforming growth factor β receptor II in mesenchymal stem cells from systemic sclerosis patients

    PubMed Central

    Vanneaux, Valérie; Farge-Bancel, Dominique; Lecourt, Séverine; Baraut, Julie; Cras, Audrey; Jean-Louis, Francette; Brun, Cécilia; Verrecchia, Franck; Larghero, Jérôme; Michel, Laurence

    2013-01-01

    Objectives The present work aimed to evaluate the expression of transforming growth factor-β (TGF-β) receptors on bone marrow-derived multipotent mesenchymal stromal cells (MSCs) in patients with systemic sclerosis (SSc) and the consequences of TGF-β activation in these cells, since MSC have potential therapeutic interest for SSc patients and knowing that TGF-β plays a critical role during the development of fibrosis in SSc. Design This is a prospective research study using MSC samples obtained from SSc patients and compared with MSC from healthy donors. Setting One medical hospital involving collaboration between an internal medicine department for initial patient recruitment, a clinical biotherapeutic unit for MSC preparation and an academic laboratory for research. Participants 9 patients with diffuse SSc for which bone marrow (BM) aspiration was prescribed by sternum aspiration before haematopoietic stem cell transplantation, versus nine healthy donors for normal BM. Primary and secondary outcome measures TGF-β, TGF-β receptor types I (TBRI) and II (TBRII) mRNA and protein expression were assessed by quantitative PCR and flow cytometry, respectively, in MSC from both SSc patients and healthy donors. MSC were exposed to TGF-β and assessed for collagen 1α2 synthesis and Smad expression. As positive controls, primary cultures of dermal fibroblasts were also analysed. Results Compared with nine controls, MSC from nine SSc patients showed significant increase in mRNA levels (p<0.002) and in membrane expression (p<0.0001) of TBRII. In response to TGF-β activation, a significant increase in collagen 1α synthesis (p<0.05) and Smad-3 phosphorylation was upregulated in SSc MSC. Similar results were obtained on eight SSc-derived dermal fibroblasts compared to six healthy controls. Conclusions TBRII gene and protein expression defect in MSC derived from SSc patients may have pathological significance. These findings should be taken into account when considering

  12. Transforming growth factor-β in breast cancer: too much, too late

    PubMed Central

    Barcellos-Hoff, Mary Helen; Akhurst, Rosemary J

    2009-01-01

    The contribution of transforming growth factor (TGF)β to breast cancer has been studied from a myriad perspectives since seminal studies more than two decades ago. Although the action of TGFβ as a canonical tumor suppressor in breast is without a doubt, there is compelling evidence that TGFβ is frequently subverted in a malignant plexus that drives breast cancer. New knowledge that TGFβ regulates the DNA damage response, which underlies cancer therapy, reveals another facet of TGFβ biology that impedes cancer control. Too much TGFβ, too late in cancer progression is the fundamental motivation for pharmaceutical inhibition. PMID:19291273

  13. Influence of phase transformation on stress evolution during growth of metal thin films on silicon.

    PubMed

    Fillon, A; Abadias, G; Michel, A; Jaouen, C; Villechaise, P

    2010-03-01

    In situ stress measurements during two-dimensional growth of low mobility metal films on amorphous Si were used to demonstrate the impact of interface reactivity and phase transformation on stress evolution. Using Mo1-xSix films as examples, the results show that the tensile stress rise, which develops after the film has become crystalline, is correlated with an increase in lateral grain size. The origin of the tensile stress is attributed to the volume change resulting from the alloy crystallization, which occurs at a concentration-dependent critical thickness. PMID:20366996

  14. A novel transforming growth factor beta2 antisense transcript in mammalian lung.

    PubMed Central

    Coker, R K; Laurent, G J; Dabbagh, K; Dawson, J; McAnulty, R J

    1998-01-01

    Transforming growth factor (TGF) beta2 gene expression was examined in murine, rat and human lung by in situ hybridization with riboprobes. Hybridization signal was observed in a variety of cells with the sense probe, and Northern-blot analysis with this probe demonstrated the presence of a novel 3.5 kb transcript. This first report suggesting the existance of a natural TGFbeta2 antisense transcript raises the possibility that such a transcript may play a role in regulating TGFbeta2 production. PMID:9601055

  15. Phase transformations during the growth of paracetamol crystals from the vapor phase

    NASA Astrophysics Data System (ADS)

    Belyaev, A. P.; Rubets, V. P.; Antipov, V. V.; Bordei, N. S.

    2014-07-01

    Phase transformations during the growth of paracetamol crystals from the vapor phase are studied by differential scanning calorimetry. It is found that the vapor-crystal phase transition is actually a superposition of two phase transitions: a first-order phase transition with variable density and a second-order phase transition with variable ordering. The latter, being a diffuse phase transition, results in the formation of a new, "pretransition," phase irreversibly spent in the course of the transition, which ends in the appearance of orthorhombic crystals. X-ray diffraction data and micrograph are presented.

  16. Phase and structural transformations in annealed copper coatings in relation to oxide whisker growth

    NASA Astrophysics Data System (ADS)

    Dorogov, M. V.; Priezzheva, A. N.; Vlassov, S.; Kink, I.; Shulga, E.; Dorogin, L. M.; Lõhmus, R.; Tyurkov, M. N.; Vikarchuk, A. A.; Romanov, A. E.

    2015-08-01

    We describe structural and phase transformation in copper coatings made of microparticles during heating and annealing in air in the temperature range up to 400 °C. Such thermal treatment is accompanied by intensive CuO nanowhisker growth on the coating surface and the formation of the layered oxide phases (Cu2O and CuO) in the coating interior. X-ray diffraction and focused ion beam (FIB) are employed to characterize the multilayer structure of annealed copper coatings. Formation of volumetric defects such as voids and cracks in the coating is demonstrated.

  17. Transforming Growth Factor-β3 Therapy Delays Postoperative Reossification and Improves Craniofacial Growth in Craniosynostotic Rabbits.

    PubMed

    Gilbert, J; Karski, M; Smith, T D; Burrows, A M; Norbutt, C; Siegel, M I; Costello, B J; Cray, J J; Losee, J E; Moursi, A M; Cooper, G M; Mooney, M P

    2016-03-01

    Postoperative reossification is a common clinical correlate following surgery. It has been suggested that an underexpression of transforming growth factor-β3 (TGF-β3) may be related to craniosynostosis and postoperative reossification. Adding TGF-β3 may delay reossification and improve postoperative growth. The present study was designed to test this hypothesis. Thirty 10-day-old New Zealand white rabbits with hereditary coronal suture synostosis were divided into three groups: (1) suturectomy controls (n = 14), (2) suturectomy treated with bovine serum albumin (n = 8), and (3) suturectomy treated with TGF-β3 protein (n = 8). At 10 days of age, a 3-mm × 15-mm coronal suturectomy was performed, and serial three-dimensional (3D) computed tomography (CT) scans and cephalographs were taken at 10, 25, 42, and 84 days of age. Calvaria were harvested at 84 days of age for histomorphometric analysis. Mean differences were analyzed using a group by age analysis of variance. Analysis of the 3D CT scan data revealed that sites treated with TGF-β3 had significantly (P < .05) greater defect areas and significantly (P < .05) greater intracranial volumes through 84 days of age compared with controls. Histomorphometry showed that sites treated with TGF-β3 had patent suturectomy sites and significantly (P < .001) less new bone in the suturectomy site compared with controls. Serial radiograph data revealed significant (P < .05) differences in craniofacial growth from 25 to 84 days in TGF-β3-treated rabbits compared with controls. Data show that TGF-β3 administration delayed reossification and improved craniofacial growth in this rabbit model. These findings also suggest that this molecular-based therapy may have potential clinical use. PMID:26090789

  18. Active Notch1 Confers a Transformed Phenotype to Primary Human Melanocytes

    PubMed Central

    Pinnix, Chelsea C.; Lee, John T.; Liu, Zhao-Jun; McDaid, Ronan; Balint, Klara; Beverly, Levi J.; Brafford, Patricia A.; Xiao, Min; Himes, Benjamin; Zabierowski, Susan E.; Yashiro-Ohtani, Yumi; Nathanson, Katherine L.; Bengston, Ana; Pollock, Pamela M.; Weeraratna, Ashani T.; Nickoloff, Brian J.; Pear, Warren S.; Capobianco, Anthony J.; Herlyn, Meenhard

    2009-01-01

    The importance of MAPK signaling in melanoma is underscored by the prevalence of activating mutations in N-Ras and B-Raf; yet, clinical development of inhibitors of this pathway has been largely ineffective, suggesting that alternative oncogenes may also promote melanoma. Notch is an interesting candidate that has only been correlated with melanoma development and progression; a thorough assessment of tumor-initiating effects of activated Notch on human melanocytes would clarify the mounting correlative evidence and perhaps identify a novel target for an otherwise untreatable disease. Analysis of a substantial panel of cell lines and patient lesions demonstrated that Notch activity is significantly higher in melanomas than their non-transformed counterparts. The use of a constitutively-active, truncated Notch transgene construct (NIC) was exploited to determine if Notch activation is a ‘driving’ event in melanocytic transformation or instead a ‘passenger’ event associated with melanoma progression. NIC-infected melanocytes displayed increased proliferative capacity and biological features more reminiscent of melanoma such as dysregulated cell adhesion and migration. Gene expression analyses supported these observations and aided in the identification of MCAM, an adhesion molecule associated with acquisition of the malignant phenotype, as a direct target of Notch transactivation. NIC-positive melanocytes grew at clonal density, proliferated in limiting media conditions, and also exhibited anchorage-independent growth suggesting that Notch, alone, is a transforming oncogene in human melanocytes, a phenomenon not previously described for any melanoma oncogene; this new information yields valuable insight into the basic epidemiology of melanoma and launches a realm of possibilities for drug intervention in this deadly disease. PMID:19549918

  19. The expression of transforming growth factor-beta by cultured chick growth plate chondrocytes: differential regulation by 1,25-dihydroxyvitamin D3.

    PubMed

    Farquharson, C; Law, A S; Seawright, E; Burt, D W; Whitehead, C C

    1996-05-01

    1,25-Dihydroxyvitamin D3 (1,25(OH)2D3) and transforming growth factor-beta (TGF-beta) are both important regulators of chondrocyte growth and differentiation. We report here that 1,25(OH)2D3 differentially regulates the expression of the genes for TGF-beta 1 to -beta 3 and the secretion of the corresponding proteins in cultured chick chondrocytes. Confluent growth plate chondrocytes were serum-deprived and cultured in varying concentrations of 1,25(OH)2D3. Cells were assayed for TGF-beta mRNA and conditioned medium was assayed for TGF-beta activity and isoform composition. Active TGF-beta was only detected in 10(-8) M 1,25(OH)2D3-treated cultures (8.37 ng active TGF-beta/mg protein). There was a significant decrease in total (latent-active) TGF-beta activity in conditioned medium of 10(-12) M (23.4%; P < 0.05) and 10(-10) M (20.7%; P < 0.05) 1,25(OH)2D3-treated cultures but 10(-8) M 1,25(OH)2D3 significantly increased (30.9%; P < 0.01) TGF-beta activity. The amounts of TGF-beta 1, -beta 2 and -beta 3 isoforms produced were similar in control, 10(-10) or 10(-12) M 1,25(OH)2D3-treated cultures but the conditioned medium of 10(-8) M 1,25(OH)2D3-treated cultures contained significantly higher amounts of all three isoforms. Quantification of TGF-beta mRNA demonstrated differential control of TGF-beta gene expression with TGF-beta 1 and -beta 3 mRNA levels reduced by all concentrations of 1,25(OH)2D3 examined (10(-8), 10(-10) and 10(-12) M) whilst TGF-beta 2 mRNA concentrations were elevated. Our results indicated that 1,25(OH)2D3 regulates chick growth plate chondrocyte TGF-beta secretion and mRNA expression in a concentration-dependent and isoform-specific manner. This interaction may be important in the regulation of chondrocyte metabolism and endochondral bone growth. PMID:8708539

  20. A methoxy derivative of resveratrol analogue selectively induced activation of the mitochondrial apoptotic pathway in transformed fibroblasts

    PubMed Central

    Gosslau, A; Chen, M; Ho, Ci-T; Chen, K Y

    2005-01-01

    Resveratrol (R-3), a trihydroxy trans-stilbene from grape, inhibits multistage carcinogenesis in animal models. A resveratrol derivative 3,4,5,4′-tetrahydroxystilbene (R-4) exhibits potent growth inhibitory effect against transformed human cells. Here we report that 3,4,5,4′-tetramethoxystilbene (MR-4), converted from R-4, was more potent against cancer cell lines (WI38VA, IMR-90SV, HeLa, LNCaP, HT-29, and HepG2), but had almost no inhibitory effect on the growth of normal cells (WI38, IMR-90, BJ-T) at the concentrations tested. The IC50 value of MR-4 on the growth inhibition of transformed WI38VA human cells was 0.5 μM, as compared to the value of greater than 50 μM for the normal WI38 cells. Resveratrol, however, did not exhibit such clear differential effect and the IC50 value of R-3 for WI38VA cells was about 50 μM. The growth inhibitory effect of MR-4 correlated with the induction of apoptosis in the transformed cells. When normal WI38 cells and transformed WI38VA cells were compared, MR-4 induced increases of the Bax/Bcl-2 mRNA ratio, p53 and Bax protein level, activation of caspases, and DNA fragmentation in transformed, but not in normal cells. Further analysis revealed that MR-4 caused a rapid appearance of perinuclear aggregation of mitochondria in WI38VA but not in WI38 cells, suggesting that the mitochondria could serve as an early target of MR-4. R-3 also induced apoptosis and mitochondrial clustering but only at a much higher concentration, close to 500 μM. Taken together, the specific activation of the mitochondria-mediated apoptotic pathway could be a major reason for the striking differential growth inhibitory effect of MR-4. PMID:15668717

  1. P21-activated protein kinase (PAK2)-mediated c-Jun phosphorylation at 5 threonine sites promotes cell transformation

    PubMed Central

    Li, Tingting; Zhang, Jishuai; Zhu, Feng; Wen, Weihong; Zykova, Tatyana; Li, Xiang; Liu, Kangdong; Peng, Cong; Ma, Weiya; Shi, Guozheng; Dong, Ziming; Bode, Ann M.; Dong, Zigang

    2011-01-01

    The oncoprotein c-Jun is one of the components of the activator protein-1 (AP-1) transcription factor complex. AP-1 regulates the expression of many genes and is involved in a variety of biological functions such as cell transformation, proliferation, differentiation and apoptosis. AP-1 activates a variety of tumor-related genes and therefore promotes tumorigenesis and malignant transformation. Here, we found that epidermal growth factor (EGF) induces phosphorylation of c-Jun by P21-activated kinase (PAK) 2. Our data showed that PAK2 binds and phosphorylates c-Jun at five threonine sites (Thr2, Thr8, Thr89, Thr93 and Thr286) in vitro and ex vivo. Knockdown of PAK2 in JB6 Cl41 (P+) cells had no effect on c-Jun phosphorylation at Ser63 or Ser73 but resulted in decreases in EGF-induced anchorage-independent cell transformation, proliferation and AP-1 activity. Mutation at all five c-Jun threonine sites phosphorylated by PAK2 decreased the transforming ability of JB6 cells. Knockdown of PAK2 in SK-MEL-5 melanoma cells also decreased colony formation, proliferation and AP-1 activity. These results indicated that PAK2/c-Jun signaling plays an important role in EGF-induced cell proliferation and transformation. PMID:21177766

  2. Estimating canopy leaf area index in the late stages of wheat growth using continuous wavelet transform

    NASA Astrophysics Data System (ADS)

    Huang, Yan; Tian, Qingjiu; Wang, Lei; Geng, Jun; Lyu, Chunguang

    2014-01-01

    The existing hyperspectral vegetation indices used for estimating the canopy leaf area index (LAI) of winter wheat (Triticum aestivum L.) performed well, but the use of such indices at late growth stages can lead to inaccurate results. To improve the performance of LAI models for wheat in late growth stages, the continuous wavelet transform (CWT) method was applied in this study and used to decompose the canopy reflectance and its first derivative into wavelet coefficients. The correlation scalograms of wavelet coefficients and the LAI were then constructed and used to extract the top 1% correlated region as the wavelet feature. The canopy LAI estimation model for late growth wheat was established at last and compared with models based on 12 different types of hyperspectral vegetation indices. The results showed that, compared with the estimation models using the hyperspectral vegetation indices (for which the R2 values were all less than 0.15 and the root-mean-square errors (RMSEs) were greater than 1), the CWT-based canopy LAI estimation model for late growth wheat had obvious improvements in accuracy (maximum R2 of 0.53 and minimum of RMSE of 0.78). Hence, this new method shows promise for use in agricultural and ecological applications.

  3. Transforming growth factor-beta in the chicken fundal layers: an immunohistochemical study.

    PubMed

    Mathis, Ute; Schaeffel, Frank

    2010-06-01

    In the chicken model of myopia, it has first been shown that imposing defocus to the retina results in active remodelling of the sclera which, in turn, results in axial length changes of the eye. Transforming growth factor-beta (TGF-beta) is one of the scleral growth modulators but its cellular localization in the fundal layers, colocalization and function are not well known. The aim of the current study was to investigate the cellular distribution of the three isoforms TGF-beta1, 2 and 3 by immunohistochemical labelling. Furthermore, the effects of visual experience that induces refractive errors on TGF-beta2 labelling were examined. Transversal cryostat sections of the fundal layers were analyzed by indirect immunofluorescent labelling and cell counts. Visual experience was changed by having the chicks wear either diffusers, or positive or negative lenses of 7D power in front of the right eyes for various periods of time. Left eyes served as uncovered controls. All TGF-beta isoforms were localized in both scleral layers. In choroid, diffuse labelling of all isoforms was found. In retina, TGF-beta1 and 3 were detected in bipolar, amacrine and ganglion cells and TGF-beta2 in amacrine and ganglion cells. To further characterize these cells, double-labelling with known amacrine and bipolar cell markers was performed (calbindin, cellular retinoic acid binding protein (CRABP), Islet1, Lim3 and protein kinase C (PKC)). TGF-beta1, 2 and 3 could be colocalized with calbindin and CRABP in single amacrine cells. TGF-beta1-positive bipolar cells were immunoreactive to Lim3. TGF-beta1 and 3 were never colocalized with PKC in bipolar cells. Also, colocalization with peptides known to be involved in myopia development in chicks, such as glucagon, or vasointestinal polypeptide and the key enzyme for dopamine synthesis, tyrosine hydroxylase, was not observed. Lenses or diffusers, worn by the chicks for various periods of time, had no effect on TGF-beta2 immunoreactivity in

  4. Constitutive Smad linker phosphorylation in melanoma: a mechanism of resistance to transforming growth factor-β-mediated growth inhibition.

    PubMed

    Cohen-Solal, Karine A; Merrigan, Kim T; Chan, Joseph L-K; Goydos, James S; Chen, Wenjin; Foran, David J; Liu, Fang; Lasfar, Ahmed; Reiss, Michael

    2011-06-01

    Melanoma cells are resistant to transforming growth factor-β (TGFβ)-induced cell-cycle arrest. In this study, we investigated a mechanism of resistance involving a regulatory domain, called linker region, in Smad2 and Smad3, main downstream effectors of TGFβ. Melanoma cells in culture and tumor samples exhibited constitutive Smad2 and Smad3 linker phosphorylation. Treatment of melanoma cells with the MEK1/2 inhibitor, U0126, or the two pan-CDK and GSK3 inhibitors, Flavopiridol and R547, resulted in decreased linker phosphorylation of Smad2 and Smad3. Overexpression of the linker phosphorylation-resistant Smad3 EPSM mutant in melanoma cells resulted in an increase in expression of p15(INK4B) and p21(WAF1) , as compared with cells transfected with wild-type (WT) Smad3. In addition, the cell numbers of EPSM Smad3-expressing melanoma cells were significantly reduced compared with WT Smad3-expressing cells. These results suggest that the linker phosphorylation of Smad3 contributes to the resistance of melanoma cells to TGFβ-mediated growth inhibition. PMID:21477078

  5. Growth Hormone Induces Transforming Growth Factor-Beta-Induced Protein in Podocytes: Implications for Podocyte Depletion and Proteinuria.

    PubMed

    Chitra, P Swathi; Swathi, T; Sahay, Rakesh; Reddy, G Bhanuprakash; Menon, Ram K; Kumar, P Anil

    2015-09-01

    The glomerular podocytes form a major size selective barrier for the filtration of serum proteins and reduced podocyte number is a critical event in the pathogenesis of proteinuria during diabetic nephropathy (DN). An elevated level of growth hormone (GH) is implicated as a causative factor in the development of nephropathy in patients with type 1 diabetes mellitus. We have previously shown that podocytes express GH receptor and are a target for GH action. To elucidate the molecular basis for the effects of GH on podocyte depletion, we conducted PCR-array analyses for extracellular matrix and adhesion molecules in podocytes. Our studies reveal that GH increases expression of a gene that encodes transforming growth factor-beta-induced protein (TGFBIp) expression. Similarly, microarray data retrieved from the Nephromine database revealed elevation of TGFBIp in patients with DN. Treatment with GH results in increased secretion of extracellular TGFBIp by podocytes. Both GH and TGFBIp induced apoptosis and epithelial mesenchymal transition (EMT) of podocytes. Exposure of podocytes to GH and TGFBIp resulted in increased migration of cells and altered podocyte permeability to albumin across podocyte monolayer. Administration of GH to rats induced EMT and apoptosis in the glomerular fraction of the kidney. Therefore, we conclude that the GH-dependent increase in TGFBIp in the podocyte is one of the mechanisms responsible for podocyte depletion in DN. PMID:25740786

  6. Dental pulp stem cells suppress the proliferation of lymphocytes via transforming growth factor-β1.

    PubMed

    Ding, Gang; Niu, Jianyi; Liu, Yi

    2015-04-01

    Dental pulp stem cells (DPSCs) possess self-renewal capability, multi-lineage differentiation potential, and can generate a dentin-pulp-like tissue in vivo, which is promising for tooth regeneration. To enlarge the cells resource of DPSCs and explore the feasibility of DPSCs-mediated immune therapy, it is prerequisite to investigate the immunological properties of DPSCs and the underlying mechanisms. Human DPSCs and peripheral blood mononuclear cells were isolated and cultured. Then we used lymphocytes proliferation assays, cytokines detection, Transwell cultures, neutralization experiments, and flow cytometry to examine the in vitro immune characteristics of DPSCs. We found that DPSCs failed to stimulate allogeneic T cells proliferation and suppressed T cells proliferation, B cells proliferation, and mixed lymphocyte reaction. In addition, DPSCs could up-regulate IL-10, down-regulate the production of IL-2, IL-17, and IFN-γ, and did not affect the production of IL-6. Monoclonal antibody against transforming growth factor-β1 restored the T cells proliferation inhibited by DPSCs. Moreover, the population of regulatory T cells increased significantly and T-helper 17 cells decreased significantly in peripheral blood mononuclear cells co-cultured with DPSCs. These data confirmed that DPSCs are low immunogenic, could inhibit the proliferation of lymphocytes, regulate the production of cytokines in vitro, and the secretion of transforming growth factor-β1 may be involved in this event. PMID:25605036

  7. Strong magnetic field-assisted growth of carbon nanofibers and its microstructural transformation mechanism

    PubMed Central

    Luo, Chengzhi; Fu, Qiang; Pan, Chunxu

    2015-01-01

    It is well-known that electric and magnetic fields can control the growth direction, morphology and microstructure of one-dimensional carbon nanomaterials (1-DCNMs), which plays a key role for its potential applications in micro-nano-electrics and devices. In this paper, we introduce a novel process for controlling growth of carbon nanofibers (CNFs) with assistance of a strong magnetic field (up to 0.5 T in the center) in a chemical vapor deposition (CVD) system. The results reveal that: 1) The CNFs get bundled when grown in the presence of a strong magnetic field and slightly get aligned parallel to the direction of the magnetic field; 2) The CNFs diameter become narrowed and homogenized with increase of the magnetic field; 3) With the increase of the magnetic field, the microstructure of CNFs is gradually changed, i.e., the strong magnetic field makes the disordered “solid-cored” CNFs transform into a kind of bamboo-liked carbon nanotubes; 4) We propose a mechanism that the reason for these variations and transformation is due to diamagnetic property of carbon atoms, so that it has direction selectivity in the precipitation process. PMID:25761381

  8. Strong magnetic field-assisted growth of carbon nanofibers and its microstructural transformation mechanism.

    PubMed

    Luo, Chengzhi; Fu, Qiang; Pan, Chunxu

    2015-01-01

    It is well-known that electric and magnetic fields can control the growth direction, morphology and microstructure of one-dimensional carbon nanomaterials (1-DCNMs), which plays a key role for its potential applications in micro-nano-electrics and devices. In this paper, we introduce a novel process for controlling growth of carbon nanofibers (CNFs) with assistance of a strong magnetic field (up to 0.5 T in the center) in a chemical vapor deposition (CVD) system. The results reveal that: 1) The CNFs get bundled when grown in the presence of a strong magnetic field and slightly get aligned parallel to the direction of the magnetic field; 2) The CNFs diameter become narrowed and homogenized with increase of the magnetic field; 3) With the increase of the magnetic field, the microstructure of CNFs is gradually changed, i.e., the strong magnetic field makes the disordered "solid-cored" CNFs transform into a kind of bamboo-liked carbon nanotubes; 4) We propose a mechanism that the reason for these variations and transformation is due to diamagnetic property of carbon atoms, so that it has direction selectivity in the precipitation process. PMID:25761381

  9. Strong magnetic field-assisted growth of carbon nanofibers and its microstructural transformation mechanism

    NASA Astrophysics Data System (ADS)

    Luo, Chengzhi; Fu, Qiang; Pan, Chunxu

    2015-03-01

    It is well-known that electric and magnetic fields can control the growth direction, morphology and microstructure of one-dimensional carbon nanomaterials (1-DCNMs), which plays a key role for its potential applications in micro-nano-electrics and devices. In this paper, we introduce a novel process for controlling growth of carbon nanofibers (CNFs) with assistance of a strong magnetic field (up to 0.5 T in the center) in a chemical vapor deposition (CVD) system. The results reveal that: 1) The CNFs get bundled when grown in the presence of a strong magnetic field and slightly get aligned parallel to the direction of the magnetic field; 2) The CNFs diameter become narrowed and homogenized with increase of the magnetic field; 3) With the increase of the magnetic field, the microstructure of CNFs is gradually changed, i.e., the strong magnetic field makes the disordered ``solid-cored'' CNFs transform into a kind of bamboo-liked carbon nanotubes; 4) We propose a mechanism that the reason for these variations and transformation is due to diamagnetic property of carbon atoms, so that it has direction selectivity in the precipitation process.

  10. Epigenetic mediated transcriptional activation of WNT5A participates in arsenical-associated malignant transformation

    SciTech Connect

    Jensen, Taylor J.; Wozniak, Ryan J.; Eblin, Kylee E.; Wnek, Sean M.; Gandolfi, A. Jay; Futscher, Bernard W.

    2009-02-15

    Arsenic is a human carcinogen with exposure associated with cancer of the lung, skin, and bladder. Many potential mechanisms have been implicated as playing a role in the process of arsenical-induced malignancy including the perturbation of signaling pathways and aberrant epigenetic regulation. We initiated studies to examine the role of a member of the non-canonical WNT signaling pathway, WNT5A, in UROtsa cells and arsenite [URO-ASSC] and monomethylarsonous acid [URO-MSC] malignantly transformed variants. We present data herein that suggest that WNT5A is transcriptionally activated during arsenical-induced malignant transformation. This WNT5A transcriptional activation is correlated with the enrichment of permissive histone modifications and the reduction of repressive modifications in the WNT5A promoter region. The epigenetic activation of WNT5A expression and acetylation of its promoter remain after the removal of the arsenical, consistent with the maintenance of an anchorage independent growth phenotype in these cells. Additionally, treatment with epigenetic modifying drugs supports a functional role for these epigenetic marks in controlling gene expression. Reduction of WNT5A using lentiviral shRNA greatly attenuated the ability of these cells to grow in an anchorage independent fashion. Extension of our model into human bladder cancer cell lines indicates that each of the cell lines examined also express WNT5A. Taken together, these data suggest that the epigenetic remodeling of the WNT5A promoter is correlated with its transcriptional activation and this upregulation likely participates in arsenical-induced malignant transformation.

  11. Vitamin D inhibition of pro-fibrotic effects of transforming growth factor β1 in lung fibroblasts and epithelial cells

    PubMed Central

    Ramirez, Allan M.; Wongtrakool, Cherry; Welch, Teresa; Steinmeyer, Andreas; Zügel, Ulrich; Roman, Jesse

    2010-01-01

    The mechanisms that control fibroproliferation and matrix deposition in lung fibrosis remain unclear. We speculate that vitamin D deficiency may contribute to pulmonary fibrosis since vitamin D deficiency has been implicated in several diseases. First, we confirmed the presence of vitamin D receptors (VDR) in cultured NIH/3T3 and lung fibroblasts. Fibroblasts transfected with a vitamin D response element – reporter construct and exposed to the active vitamin D metabolite, 1,25(OH)2D3, showed increased promoter activity indicating VDR functionality in these cells. Testing the effects of 1,25(OH)2D3 on fibroblasts treated with transforming growth factor β1 (TGFβ1), considered a driver of many fibrotic disorders, we found that 1,25(OH)2D3 inhibited TGFβ1-induced fibroblast proliferation in a dose-dependent fashion. 1,25(OH)2D3 also inhibited TGFβ1 stimulation of α-smooth muscle actin expression and polymerization and prevented the upregulation of fibronectin and collagen in TGFβ1-treated fibroblasts. Finally, we examined how 1,25(OH)2D3 affects epithelial-mesenchymal transformation of lung epithelial cells upon exposure to TGFβ1. We showed that the TGFβ1-induced upregulation of mesenchymal cell markers and abnormal expression of epithelial cell markers were blunted by 1,25(OH)2D3. These observations suggest that under TGFβ1 stimulation, 1,25(OH)2D3 inhibits the profibrotic phenotype of lung fibroblasts and epithelial cells. PMID:19931390

  12. Protopanaxatirol type ginsenoside Re promotes cyclic growth of hair follicles via inhibiting transforming growth factor β signaling cascades.

    PubMed

    Li, Zheng; Ryu, Seung-Wook; Lee, Jungsul; Choi, Kyungsun; Kim, Sunchang; Choi, Chulhee

    2016-02-19

    Ginsenosides, the major bio-active ingredients included in Panax ginseng, have been known for the hair growth activity and used to treat patients who suffer from hair loss; however, the detailed mechanisms of this action are still largely unknown. This study was conducted to investigate the molecular and cellular mechanisms responsible for hair growth promoting effect of ginsenoside Re (GRe) in vitro and in vivo. Different doses of minoxidil and GRe were administered topically to the back regions of nude mice for up to 45 days, and hair shaft length and hair cycles were determined for hair promoting activities. Topical treatment of GRe significantly increased the hair shaft length and hair existent time, which was comparable to the action of minoxidil. We also demonstrated that GRe stimulated hair shaft elongation in the ex vivo cultures of vibrissa hair follicles isolated from C57BL/6 mouse. Systemic transcriptome analysis by next generation sequencing demonstrated that TGF-β-pathway related genes were selectively down-regulated by treatment of GRe in vivo, and the same treatment suppressed TGF-β-induced phosphorylation of ERK in HeLa cells. The results clearly indicated that GRe is the effective constituent in the ginseng on hair promotion via selective inhibition of the hair growth phase transition related signaling pathways, TGF-β signaling cascades. PMID:26820528

  13. Transforming growth factor-betas and their signaling receptors are coexpressed in Crohn's disease.

    PubMed Central

    di Mola, F F; Friess, H; Scheuren, A; Di Sebastiano, P; Graber, H; Egger, B; Zimmermann, A; Korc, M; Büchler, M W

    1999-01-01

    OBJECTIVE: To evaluate mechanisms that contribute to tissue repair and tissue remodeling in Crohn's disease (CD). SUMMARY BACKGROUND DATA: Transforming growth factor-betas (TGF-betas) are involved in different chronic inflammatory disorders. They function by binding to two receptors, type I (TbetaR-I) subtype ALK5 and type II (TbetaR-II), which are concomitantly required for signal transduction. METHODS: Tissues were obtained from 18 patients with CD (10 female patients, 8 male patients, median age 38.7 years [range 16 to 58 years]) undergoing surgery because of CD-related complications. Tissue samples of 18 healthy organ donors (10 female subjects, 8 male subjects, median age 50.3 years [range 15 to 65 years]) served as controls. The expression and localization of TGF-beta1, TGF-beta2, TGF-beta3, TbetaR-IALK5, TbetaR-II, and TbetaR-III were studied by Northern blot analysis, in situ hybridization, and immunohistochemistry. RESULTS: On Northern blot analysis, 94% of the CD samples exhibited enhanced TGF-beta1, TGF-beta3, and TbetaR-II mRNA expression compared with controls. TGF-beta2 was increased in 72%, TbetaR-IALK5 in 72%, and TbetaR-III in 82% of the patients with CD. On in situ hybridization and immunohistochemical analysis, TGF-beta1, TbetaR-IALK5, and TbetaR-II were seen to be colocalized in the lamina propria cells and in the lymphocytes closest to the luminal surface, but also in the remaining epithelial cells, and in fibroblasts of CD tissue samples. CONCLUSIONS: The concomitant overexpression of TGF-betas and their signaling receptors in CD points to a potential role of these regulatory molecules in the pathophysiology of CD. Activation of TGF-beta-mediated pathways might promote the repair of mucosal injury by enhancing the process of reepithelization, but might also contribute to extracellular matrix generation and subsequently to intramural fibrosis and intestinal obstruction. Images Figure 1. Figure 3. Figure 4. Figure 5. PMID:9923802

  14. Construction of DNA recognition sites active in Haemophilus transformation.

    PubMed Central

    Danner, D B; Smith, H O; Narang, S A

    1982-01-01

    Competent Haemophilus cells recognize and preferentially take up Haemophilus DNA during genetic transformation. This preferential uptake is correlated with the presence on incoming DNA of an 11-base-pair (bp) sequence, 5'-A-A-G-T-G-C-G-G-T-C-A-3'. To prove that this sequence is the recognition site that identifies Haemophilus DNA to the competent cell, we have now constructed a series of plasmids, each of which contains the 11-bp sequence. Using two different assay systems we have tested the ability of fragments from these plasmids to compete with cloned Haemophilus DNA fragments that naturally contain the 11-bp sequence. We find that the addition of the 11-bp sequence to a DNA fragment is necessary and sufficient for preferential uptake of that fragment. However, plasmid DNAs containing this sequence may vary as much as 48-fold in uptake activity, and this variation correlates with the A+T-richness of the DNA flanking the 11-mer. Images PMID:6285382

  15. Angiotensin II-induced hypertrophy of cultured murine proximal tubular cells is mediated by endogenous transforming growth factor-beta.

    PubMed Central

    Wolf, G; Mueller, E; Stahl, R A; Ziyadeh, F N

    1993-01-01

    Previous studies by our group have demonstrated that angiotensin II (ANG II), as a single factor in serum-free medium, induces cellular hypertrophy of a cultured murine proximal tubular cell line (MCT). The present study was performed to test the hypothesis that this growth effect was mediated by activation of endogenous transforming growth factor-beta (TGF-beta). Exogenous TGF-beta 1 (1 ng/ml) mimicked the growth effects observed with 10(-8) M ANG II (inhibition of DNA synthesis and induction of cellular hypertrophy). A neutralizing anti-TGF-beta antibody attenuated the ANG II-induced increase in de novo protein and total RNA synthesis as well as total protein content. This antibody also abolished the ANG II-mediated inhibition of [3H]thymidine incorporation into quiescent MCT cells. Control IgG or an unrelated antibody had no effect. A bioassay for TGF-beta using mink lung epithelial cells revealed that MCT cells treated with ANG II released active TGF-beta into the cell culture supernatant. Northern blot analysis and semi-quantitative cDNA amplification demonstrated increases in steady-state levels for TGF-beta 1 mRNA after ANG II stimulation of MCT cells, but not in a syngeneic murine mesangial cell line. Our data indicate that the ANG II-induced hypertrophy in MCT cells is mediated by synthesis and activation of endogenous TGF-beta. It is intriguing to speculate that TGF-beta may play a role in the early tubular cell hypertrophy and the subsequent interstitial scarring observed in several models of chronic renal injury that are characterized by increased activity of intrarenal ANG II. Images PMID:7690779

  16. Stage-Specific Profiling of Transforming Growth Factor-β, Fibroblast Growth Factor and Wingless-int Signaling Pathways during Early Embryo Development in The Goat

    PubMed Central

    HosseinNia, Pouria; Tahmoorespur, Mojtaba; Hosseini, Sayyed Morteza; Hajian, Mehdi; Ostadhosseini, Somayeh; Nasiri, Mohammad Reza; Nasr-Esfahani, Mohammad Hossein

    2016-01-01

    Objective This research intends to unravel the temporal expression profiles of genes in- volved in three developmentally important signaling pathways [transforming growth factor-β (TGF-β), fibroblast growth factor (FGF) and wingless/int (WNT)] during preand peri-implan- tation goat embryo development. Materials and Methods In this experimental study, we examined the transcripts that encoded the ligand, receptor, intracellular signal transducer and modifier, and the down- stream effector, for each signaling pathway. In vitro mature MII oocytes and embryos at three distinctive stages [8-16 cell stage, day-7 (D7) blastocysts and day-14 (D14) blas- tocysts] were separately prepared in triplicate for comparative real-time reverse tran- scriptase polymerase chain reaction (RT-PCR) using the selected gene sets. Results Most components of the three signaling pathways were present at more or less stable levels throughout the assessed oocyte and embryo developmental stages. The transcripts for TGF-β, FGF and WNT signaling pathways were all induced in unfertilized MII-oocytes. However, developing embryos showed gradual patterns of decrease in the activities of TGF-β, FGF and WNT components with renewal thereafter. Conclusion The results suggested that TGF-β, FGF and WNT are maternally active signaling pathways required during earlier, rather than later, stages of preand peri- implantation goat embryo development. PMID:26862524

  17. The transforming growth factor beta type II receptor can replace the activin type II receptor in inducing mesoderm.

    PubMed Central

    Bhushan, A; Lin, H Y; Lodish, H F; Kintner, C R

    1994-01-01

    The type II receptors for the polypeptide growth factors transforming growth factor beta (TGF-beta) and activin belong to a new family of predicted serine/threonine protein kinases. In Xenopus embryos, the biological effects of activin and TGF-beta 1 are strikingly different; activin induces a full range of mesodermal cell types in the animal cap assay, while TGF-beta 1 has no effects, presumably because of the lack of functional TGF-beta receptors. In order to assess the biological activities of exogenously added TGF-beta 1, RNA encoding the TGF-beta type II receptor was introduced into Xenopus embryos. In animal caps from these embryos, TGF-beta 1 and activin show similar potencies for induction of mesoderm-specific mRNAs, and both elicit the same types of mesodermal tissues. In addition, the response of animal caps to TGF-beta 1, as well as to activin, is blocked by a dominant inhibitory ras mutant, p21(Asn-17)Ha-ras. These results indicate that the activin and TGF-beta type II receptors can couple to similar signalling pathways and that the biological specificities of these growth factors lie in their different ligand-binding domains and in different competences of the responding cells. Images PMID:8196664

  18. Uric acid and transforming growth factor in fructose-induced production of reactive oxygen species in skeletal muscle.

    PubMed

    Madlala, Hlengiwe P; Maarman, Gerald J; Ojuka, Edward

    2016-04-01

    The consumption of fructose, a major constituent of the modern diet, has raised increasing concern about the effects of fructose on health. Research suggests that excessive intake of fructose (>50 g/d) causes hyperuricemia, insulin resistance, mitochondrial dysfunction, de novo lipogenesis by the liver, and increased production of reactive oxygen species (ROS) in muscle. In a number of tissues, uric acid has been shown to stimulate the production of ROS via activation of transforming growth factor β1 and NADPH (nicotinamide adenine dinucleotide phosphate) oxidase 4. The role of uric acid in fructose-induced production of ROS in skeletal muscle, however, has not been investigated. This review examines the evidence for fructose-induced production of ROS in skeletal muscle, highlights proposed mechanisms, and identifies gaps in current knowledge. PMID:26946251

  19. Personalized risk assessment of heart failure patients: more perspectives from transforming growth factor super-family members.

    PubMed

    Goletti, S; Gruson, D

    2015-03-30

    More personalized risk assessment of patients with heart failure (HF) is important to develop more tailored based care and for a better allocation of resources. The measurement of biomarkers is now part of the standards of care and is important for the sub-phenotyping of HF patients to demonstrate the activation of pathophysiological pathways engaged in the worsening of HF. The sub-phenotyping of patients can lead therefore to a more personalized selection of the treatment. Several members of the transforming growth factor β (TGF-β) super-family, such as myostatin, activin A, GDF-15 and GDF-11, are involved in cardiac remodeling and the evaluation of their circulating levels might provide new insights to the course of the disease and also to guide prognostication and therapeutic selection of HF patients. PMID:25260834

  20. In situ electron microscope study of the phase transformation, structure and growth of thin Te1-xSex films

    NASA Astrophysics Data System (ADS)

    Vermaak, J. S.; Raubenheimer, D.

    1988-01-01

    An in-situ electron microscope technique was utilized to observe directly the amorphous-to-crystalline phase transformation, the isothermal growth rates, as well as the orientation and structure of the recrystallized films for the Te1-xSex alloy system for x=0.2, 0.3 and 0.4. Activation energies of E=0.91, 0.93 and 0.96 eV and crystallization temperatures of Tc=-14, 81.5 and 85°C for the three alloys, respectively, were found. In all three cases the crystallization process originated from single crystalline nuclei with a hexagonal structure and with the c-axis in general parallel to the substrate surface.

  1. Reduced susceptibility of mice overexpressing transforming growth factor α to dextran sodium sulphate induced colitis

    PubMed Central

    Egger, B; Carey, H; Procaccino, F; Chai, N; Sandgren, E; Lakshmanan, J; Buslon, V; French, S; Buchler, M; Eysselein, V

    1998-01-01

    Background—Transforming growth factor α (TGF-α) knockout mice have increased susceptibility to dextran sodium sulphate (DSS) induced colitis. 
Aim—To substantiate the findings that TGF-α is a key mediator of colonic mucosal protection and/or repair mechanisms by evaluating the susceptibility of mice overexpressing TGF-α to DSS induced colitis. 
Methods—TGF-α overexpression was induced in transgenic mice by ZnSO4 administration in drinking water (TG+). Three groups were used as controls: one transgenic group without ZnSO4 administration (TG−), and two non-transgenic littermate groups receiving ZnSO4 (Non-TG+) or only water (Non-TG−). Acute colitis was induced in all groups by administration of DSS (5%, w/v) in drinking water for six days ad libitum. 
Results—About 35-39% of the entire colonic mucosa was destroyed in Non-TG−, Non-TG+, and TG− animals compared with 9% in TG+ mice. The crypt damage score was 18.7 (0.9), 18.2 (1.0), 18.9(0.8), and 6.8 (1.5) (means (SEM)) in Non-TG−, Non-TG+, TG−, and TG+ mice respectively. Mucin and bromodeoxyuridine staining were markedly enhanced in colons of TG+ mice compared with controls, indicating increased mucosal protection and regeneration. 
Conclusions—The significantly reduced susceptibility of mice overexpressing TGF-α to DSS further substantiates that endogenous TGF-α is a pivotal mediator of protection and/or healing mechanisms in the colon. 

 Keywords: transforming growth factor α; epidermal growth factor; dextran sodium sulphate; colitis; inflammatory bowel disease; transgenic mice PMID:9771407

  2. Regulation of Transforming Growth Factor β1, Platelet-Derived Growth Factor, and Basic Fibroblast Growth Factor by Silicone Gel Sheeting in Early-Stage Scarring

    PubMed Central

    Choi, Jaehoon; Lee, Eun Hee; Park, Sang Woo

    2015-01-01

    Background Hypertrophic scars and keloids are associated with abnormal levels of growth factors. Silicone gel sheets are effective in treating and preventing hypertrophic scars and keloids. There has been no report on the change in growth factors in the scar tissue following the use of silicone gel sheeting for scar prevention. A prospective controlled trial was performed to evaluate whether growth factors are altered by the application of a silicone gel sheet on a fresh surgical scar. Methods Four of seven enrolled patients completed the study. Transforming growth factor (TGF)-β1, platelet-derived growth factor (PDGF), and basic fibroblast growth factor (bFGF) were investigated immunohistochemically in biopsies taken from five scars at 4 months following surgery. Results In both the epidermis and the dermis, the expression of TGF-β1 (P=0.042 and P=0.042) and PDGF (P=0.043 and P=0.042) was significantly lower in the case of silicone gel sheet-treated scars than in the case of untreated scars. The expression of bFGF in the dermis was significantly higher in the case of silicone gel sheet-treated scars than in the case of untreated scars (P=0.042), but in the epidermis, the expression of bFGF showed no significant difference between the groups (P=0.655). Conclusions The levels of TGF-β1, PDGF, and bFGF are altered by the silicone gel sheet treatment, which might be one of the mechanisms of action in scar prevention. PMID:25606485

  3. Mammary tumor suppression by transforming growth factor beta 1 transgene expression.

    PubMed Central

    Pierce, D F; Gorska, A E; Chytil, A; Meise, K S; Page, D L; Coffey, R J; Moses, H L

    1995-01-01

    In cell culture, type alpha transforming growth factor (TGF-alpha) stimulates epithelial cell growth, whereas TGF-beta 1 overrides this stimulatory effect and is growth inhibitory. Transgenic mice that overexpress TGF-alpha under control of the mouse mammary tumor virus (MMTV) promoter/enhancer exhibit mammary ductal hyperplasia and stochastic development of mammary carcinomas, a process that can be accelerated by administration of the chemical carcinogen 7,12-dimethylbenz[a]anthracene. MMTV-TGF-beta 1 transgenic mice display mammary ductal hypoplasia and do not develop mammary tumors. We report that in crossbreeding experiments involving the production of mice carrying both the MMTV-TGF-beta 1 and MMTV-TGF-alpha transgenes, there is marked suppression of mammary tumor formation and that MMTV-TGF-beta 1 transgenic mice are resistant to 7,12-dimethylbenz[a]anthracene-induced mammary tumor formation. These data demonstrate that overexpression of TGF-beta 1 in vivo can markedly suppress mammary tumor development. Images Fig. 1 Fig. 3 PMID:7753792

  4. Microsatellite mutation of type II transforming growth factor-beta receptor is rare in atherosclerotic plaques.

    PubMed

    Clark, K J; Cary, N R; Grace, A A; Metcalfe, J C

    2001-04-01

    A somatic mutation within a microsatellite polyA tract in the coding region of the type II transforming growth factor (TGF)-beta receptor gene was reported to occur in human atherosclerotic and restenotic lesions. This mutation occurs frequently in colorectal cancer with the replication error repair phenotype and results in loss of sensitivity to the growth inhibitory effects of TGF-beta in cells from the tumors. The mutation was proposed to account for the clonal expansion of vascular smooth muscle cells observed in atherosclerotic plaques, through loss of the growth inhibitory effect of TGF-beta. The frequency of the mutation and the extent of clonal expansion of the mutated cells have major implications for the mechanism of atherogenesis and therapeutic strategies. We analyzed a set of 22 coronary arterial and 9 aortic samples containing early to advanced atherosclerotic lesions for the mutation in the type II TGF-beta receptor polyA tract. Only 1 coronary arterial sample from an advanced lesion showed detectable amounts of the mutation, present at a low level (8% of the DNA sample). The data imply that the mutation occurs only at low frequency and is not a major mechanistic contributor to the development of atherosclerosis. PMID:11304472

  5. Immunohistochemical localization of transforming growth factor beta isoforms in asbestos-related diseases.

    PubMed Central

    Jagirdar, J; Lee, T C; Reibman, J; Gold, L I; Aston, C; Bégin, R; Rom, W N

    1997-01-01

    Transforming growth factor beta (TGF-beta), a multifunctional cytokine and growth factor, plays a key role in scarring and fibrotic processes because of its ability to induce extracellular matrix proteins and modulate the growth and immune function of many cell types. These effects are important in inflammatory disorders with fibrosis and cancer. The asbestos-related diseases are characterized by fibrosis in the lower respiratory tract and pleura and increased occurrence of lung cancer and mesothelioma. We performed immunohistochemistry with isoform-specific antibodies to the three TGF-beta isoforms on 16 autopsy lungs from Quebec, Canada, asbestos miners and millers. There was increased immunolocalization of all three TGF-beta isoforms in the fibrotic lesions of asbestosis and pleural fibrosis. The hyperplastic type II pneumocytes contained all three isoforms. By contrast, there was differential spatial immunostaining for the TGF-beta isoforms in malignant mesothelioma, with TGF-beta 1 in the stroma but TGF-beta 2 in the tumor cells. These data are consistent with an important role for TGF-beta in accumulation of extracellular matrix and cell proliferation in asbestos-related diseases. Images Figure 1. Figure 2. Figure 3. Figure 4. Figure 5. Figure 6. Figure 7. Figure 8. Figure 9. PMID:9400723

  6. Transforming growth factor-β1 induces fibrosis in rat meningeal mesothelial cells via the p38 signaling pathway.

    PubMed

    Yue, Xue-Jing; Guo, Yan; Yang, Hai-Jie; Feng, Zhi-Wei; Li, Tong; Xu, Yu-Ming

    2016-08-01

    Leptomeningeal fibrosis is important in the pathogenesis of communicating hydrocephalus following subarachnoid hemorrhage; however, the underlying mechanisms of leptomeningeal fibrosis remain largely unclear. In the present study, primary meningeal mesothelial cells (MMCs) were used as a cell model to investigate the effect of transforming growth factor‑β1 (TGF‑β1) on leptomeningeal fibrosis. Firstly, primary MMCs were isolated from rat brains and characterized by immunofluorescene, staining positive for keratin and vimentin, but negative for factor VIII. Upon TGF‑β1 treatment, MMCs were induced to express connective tissue growth factor (CTGF), an indicator of fibrosis, in a dose‑dependent manner. Furthermore, p38 mitogen‑activated protein kinase (MAPK) signaling was significantly activated by TGF‑β1. However, in the presence of a p38 MAPK inhibitor, TGF‑β1‑induced CTGF expression was markedly suppressed. Together, these data suggest that TGF‑β1 could induce fibrosis of MMCs via the p38 MAPK signaling pathway, providing a novel potential target for intervention in TGF‑β1‑induced leptomeningeal fibrosis. PMID:27314440

  7. cap alpha. -transforming growth factor secreted by untransformed bovine anterior pituitary cells in culture. I. Purification from conditioned medium

    SciTech Connect

    Samsoondar, J.; Kobrin, M.S.; Kudlow, J.E.

    1986-11-05

    A 6-kDa ..cap alpha..-transforming growth factor (TGF) was purified 100,000-fold to homogeneity from the culture fluid conditioned by normal bovine anterior pituitary-derived cells. Initial purification of the acid-soluble TGF from concentrated conditioned medium was achieved by Bio-Gel P-60 gel filtration (apparent molecular mass of 9 kDa). After the Bio-Gel step, three different steps of reverse-phase fast-protein liquid chromatography on the same Pharmacia C/sub 18/ column, using linear acetonitrile gradients, gave complete purification. The ion-pairing agents used in the three consecutive steps were: 0.1% trifluoroacetic acid, 0.13% heptafluorobutyric acid, and again, 0.1% trifluoroacetic acid at a shallower gradient. Homogeneity was confirmed by reverse-phase high performance liquid chromatography, and by polyacrylamide gel electrophoresis, where TGF visualization was facilitated by autoradiography of /sup 125/I-TGF. The /sup 125/I-TGF bound to epidermal growth factor (EGF) receptors and after elution ran identically to the starting material. The molecular mass of TGF is 6 kDa by polyacrylamide gel electrophoresis and 6.6 kDa by amino acid analysis. The amino acid composition of bovine TGF is similar to that of rat or human ..cap alpha..TGF and distinct from epidermal growth factor. Colony-stimulating activity was lost after purification, but the TGF retained its ability to stimulate thymidine uptake by quiescent cells. This mitogenic activity could be blocked completely by anti-EGF-receptor monoclonal antibodies, indicating that the activity was mediated through the EGF-receptor.

  8. Poxviral Protein A52 Stimulates p38 Mitogen-activated Protein Kinase (MAPK) Activation by Causing Tumor Necrosis Factor Receptor-associated Factor 6 (TRAF6) Self-association Leading to Transforming Growth Factor β-activated Kinase 1 (TAK1) Recruitment*

    PubMed Central

    Stack, Julianne; Hurst, Tara P.; Flannery, Sinead M.; Brennan, Kiva; Rupp, Sebastian; Oda, Shun-ichiro; Khan, Amir R.; Bowie, Andrew G.

    2013-01-01

    Vaccinia virus encodes a number of proteins that inhibit and manipulate innate immune signaling pathways that also have a role in virulence. These include A52, a protein shown to inhibit IL-1- and Toll-like receptor-stimulated NFκB activation, via interaction with interleukin-1 receptor-associated kinase 2 (IRAK2). Interestingly, A52 was also found to activate p38 MAPK and thus enhance Toll-like receptor-dependent IL-10 induction, which was TRAF6-dependent, but the manner in which A52 manipulates TRAF6 to stimulate p38 activation was unclear. Here, we show that A52 has a non-canonical TRAF6-binding motif that is essential for TRAF6 binding and p38 activation but dispensable for NFκB inhibition and IRAK2 interaction. Wild-type A52, but not a mutant defective in p38 activation and TRAF6 binding (F154A), caused TRAF6 oligomerization and subsequent TRAF6-TAK1 association. The crystal structure of A52 shows that it adopts a Bcl2-like fold and exists as a dimer in solution. Residue Met-65 was identified as being located in the A52 dimer interface, and consistent with that, A52-M65E was impaired in its ability to dimerize. A52-M65E although capable of interacting with TRAF6, was unable to cause either TRAF6 self-association, induce the TRAF6-TAK1 association, or activate p38 MAPK. The results suggest that an A52 dimer causes TRAF6 self-association, leading to TAK1 recruitment and p38 activation. This reveals a molecular mechanism whereby poxviruses manipulate TRAF6 to activate MAPKs (which can be proviral) without stimulating antiviral NFκB activation. PMID:24114841

  9. How should enzyme activities be used in fish growth studies?

    PubMed

    Pelletier; Blier; Dutil; Guderley

    1995-01-01

    The activity of glycolytic and oxidative enzymes was monitored in the white muscle of Atlantic cod Gadus morhua experiencing different growth rates. A strong positive relationship between the activity of two glycolytic enzymes and individual growth rate was observed regardless of whether the enzyme activity was expressed as units per gram wet mass, units per gram dry mass or with respect to muscle protein and DNA content. The most sensitive response to growth rate was observed when pyruvate kinase and lactate dehydrogenase activities were expressed as units per microgram DNA, and this may be useful as an indicator of growth rate in wild fish. In contrast, no relationship between the activities of oxidative enzymes and growth rate was observed when cytochrome c oxidase and citrate synthase activities were expressed as units per gram protein. Apparently, the aerobic capacity of white muscle in cod is not specifically increased to match growth rate. PMID:9319392

  10. Autophosphorylation on S614 inhibits the activity and the transforming potential of BRAF.

    PubMed

    Dernayka, Layal; Rauch, Nora; Jarboui, Mohamed-Ali; Zebisch, Armin; Texier, Yves; Horn, Nicola; Romano, David; Gloeckner, Christian Johannes; Kriegsheim, Alex von; Ueffing, Marius; Kolch, Walter; Boldt, Karsten

    2016-09-01

    The BRAF proto-oncogene serine/threonine-protein kinase, known as BRAF, belongs to the RAF kinase family. It regulates the MAPK/ERK signalling pathway affecting several cellular processes such as growth, survival, differentiation, and cellular transformation. BRAF is mutated in ~8% of all human cancers with the V600E mutation constituting ~90% of mutations. Here, we have used quantitative mass spectrometry to map and compare phosphorylation site patterns between BRAF and BRAF V600E. We identified sites that are shared as well as several quantitative differences in phosphorylation abundance. The highest difference is phosphorylation of S614 in the activation loop which is ~5fold enhanced in BRAF V600E. Mutation of S614 increases the kinase activity of both BRAF and BRAF V600E and the transforming ability of BRAF V600E. The phosphorylation of S614 is mitogen inducible and the result of autophosphorylation. These data suggest that phosphorylation at this site is inhibitory, and part of the physiological shut-down mechanism of BRAF signalling. PMID:27345148

  11. Inhibition of endogenous heat shock protein 70 attenuates inducible nitric oxide synthase induction via disruption of heat shock protein 70/Na(+) /H(+) exchanger 1-Ca(2+) -calcium-calmodulin-dependent protein kinase II/transforming growth factor β-activated kinase 1-nuclear factor-κB signals in BV-2 microglia.

    PubMed

    Huang, Chao; Lu, Xu; Wang, Jia; Tong, Lijuan; Jiang, Bo; Zhang, Wei

    2015-08-01

    Inducible nitric oxide synthase (iNOS) critically contributes to inflammation and host defense. The inhibition of heat shock protein 70 (Hsp70) prevents iNOS induction in lipopolysaccharide (LPS)-stimulated macrophages. However, the role and mechanism of endogenous Hsp70 in iNOS induction in microglia remains unclear. This study addresses this issue in BV-2 microglia, showing that Hsp70 inhibition or knockdown prevents LPS-induced iNOS protein expression and nitric oxide production. Real-time PCR experiments showed that LPS-induced iNOS mRNA transcription was blocked by Hsp70 inhibition. Further studies revealed that the inhibition of Hsp70 attenuated LPS-stimulated nuclear translocation and phosphorylation of nuclear factor (NF)-κB as well as the degradation of inhibitor of κB (IκB)-α and phosphorylation of IκB kinase β (IKKβ). This prevention effect of Hsp70 inhibition on IKKβ-NF-κB activation was found to be dependent on the Ca(2+) /calcium-calmodulin-dependent protein kinase II (CaMKII)/transforming growth factor β-activated kinase 1 (TAK1) signals based on the following observations: 1) chelation of intracellular Ca(2+) or inhibition of CaMKII reduced LPS-induced increases in TAK1 phosphorylation and 2) Hsp70 inhibition reduced LPS-induced increases in CaMKII/TAK1 phosphorylation, intracellular pH value, [Ca(2+) ]i , and CaMKII/TAK1 association. Mechanistic studies showed that Hsp70 inhibition disrupted the association between Hsp70 and Na(+) /H(+) exchanger 1 (NHE1), which is an important exchanger responsible for Ca(2+) influx in LPS-stimulated cells. These studies demonstrate that the inhibition of endogenous Hsp70 attenuates the induction of iNOS, which likely occurs through the disruption of NHE1/Hsp70-Ca(2+) -CaMKII/TAK1-NF-κB signals in BV-2 microglia, providing further insight into the functions of Hsp70 in the CNS. PMID:25691123

  12. Interferon-alpha inhibits murine macrophage transforming growth factor-beta mRNA expression.

    PubMed

    Dhanani, S; Huang, M; Wang, J; Dubinett, S M

    1994-06-01

    Transforming growth factor-beta (TGF-beta), a multifunctional polypeptide is produced by a wide variety of cells and regulates a broad array of physiological and pathological functions. TGF-beta appears to play a central role in pulmonary fibrosis and may contribute to tumor-associated immunosuppression. Alveolar macrophages are a rich source of TGF-beta and are intimately involved in lung inflammation. We therefore chose to study TGF-beta regulation in murine alveolar macrophages as well as an immortalized peritoneal macrophage cell line (IC-21). Murine macrophages were incubated with cytokines to evaluate their role in regulating TGF-beta mRNA expression. We conclude that IFN-alpha downregulates TGF-beta mRNA expression in murine macrophages. PMID:8088926

  13. The pleiotropic roles of transforming growth factor beta inhomeostasis and carcinogenesis of endocrine organs.

    SciTech Connect

    Fleisch, Markus C.; Maxwell, Christopher A.; Barcellos-Hoff,Mary-Helen

    2006-01-13

    Transforming growth factor beta (TGF-beta) is a ubiquitous cytokine that plays a critical role in numerous pathways regulating cellular and tissue homeostasis. TGF-beta is regulated by hormones and is a primary mediator of hormone response in uterus, prostate and mammary gland. This review will address the role of TGF-beta in regulating hormone dependent proliferation and morphogenesis. The subversion of TGF-beta regulation during the processes of carcinogenesis, with particular emphasis on its effects on genetic stability and epithelial to mesenchymal transition (EMT), will also be examined. An understanding of the multiple and complex mechanisms of TGF-beta regulation of epithelial function, and the ultimate loss of TGF-beta function during carcinogenesis, will be critical in the design of novel therapeutic interventions for endocrine-related cancers.

  14. Transforming growth factor-β: an important mediator in Helicobacter pylori-associated pathogenesis

    PubMed Central

    Li, Nianshuang; Xie, Chuan; Lu, Nong-Hua

    2015-01-01

    Helicobacter pylori (H.pylori) is a Gram-negative, microaerophilic, helical bacillus that specifically colonizes the gastric mucosa. The interaction of virulence factors, host genetic factors, and environmental factors contributes to the pathogenesis of H. pylori-associated conditions, such as atrophic gastritis and intestinal metaplasia. Infection with H. pylori has recently been recognized as the strongest risk factor for gastric cancer. As a pleiotropic cytokine, transforming growth factor (TGF)-β regulates various biological processes, including cell cycle, proliferation, apoptosis, and metastasis. Recent studies have shed new light on the involvement of TGF-β signaling in the pathogenesis of H. pylori infection. This review focuses on the potential etiological roles of TGF-β in H. pylori-mediated gastric pathogenesis. PMID:26583078

  15. Mechanistic basis and clinical relevance of the role of transforming growth factor-β in cancer

    PubMed Central

    Lin, Run-Long; Zhao, Lu-Jun

    2015-01-01

    Transforming growth factor-β (TGF-β) is a key factor in cancer development and progression. TGF-β can suppress tumorigenesis by inhibiting cell cycle progression and stimulating apoptosis in early stages of cancer progression. However, TGF-β can modulate cancer-related processes, such as cell invasion, distant metastasis, and microenvironment modification that may be used by cancer cells to their advantage in late stages. Corresponding mechanisms include angiogenesis promotion, anti-tumor immunity suppression, and epithelial-to-mesenchymal transition (EMT) induction. The correlation between TGF-β expression and cancer prognosis has also been extensively investigated. Results suggest that TGF-β pathway can be targeted to treat cancer; as such, the feasibility of this treatment is investigated in clinical trials. PMID:26779375

  16. The Role of Transforming Growth Factor β1 in the Regulation of Blood Pressure

    PubMed Central

    Matsuki, Kota; Hathaway, Catherine K.; Lawrence, Marlon G.; Smithies, Oliver; Kakoki, Masao

    2016-01-01

    Although human association studies suggest a link between polymorphisms in the gene encoding transforming growth factor (TGF) β1 and differing blood pressure levels, a causative mechanism for this correlation remains elusive. Recently we have generated a series of mice with graded expression of TGFβ1, ranging from approximately 10% to 300% compared to normal. We have found that blood pressure and plasma volume are negatively regulated by TGFβ1. Of note, the 10% hypomorph exhibits primary aldosteronism and markedly impaired urinary excretion of water and electrolytes. We here review previous literature highlighting the importance of TGFβ signaling as a natriuretic system, which we postulate is a causative mechanism explaining how polymorphisms in TGFβ1 could influence blood pressure levels. PMID:25801626

  17. CYLD negatively regulates transforming growth factor-β-signalling via deubiquitinating Akt

    PubMed Central

    Lim, Jae Hyang; Jono, Hirofumi; Komatsu, Kensei; Woo, Chang-Hoon; Lee, Jiyun; Miyata, Masanori; Matsuno, Takashi; Xu, Xiangbin; Huang, Yuxian; Zhang, Wenhong; Park, Soo Hyun; Kim, Yu-Il; Choi, Yoo-Duk; Shen, Huahao; Heo, Kyung-Sun; Xu, Haodong; Bourne, Patricia; Koga, Tomoaki; Xu, Haidong; Yan, Chen; Wang, Binghe; Chen, Lin-Feng; Feng, Xin-Hua; Li, Jian-Dong

    2012-01-01

    Lung injury, whether induced by infection or caustic chemicals, initiates a series of complex wound-healing responses. If uncontrolled, these responses may lead to fibrotic lung diseases and loss of function. Thus, resolution of lung injury must be tightly regulated. The key regulatory proteins required for tightly controlling the resolution of lung injury have yet to be identified. Here we show that loss of deubiquitinase CYLD led to the development of lung fibrosis in mice after infection with Streptococcus pneumoniae. CYLD inhibited transforming growth factor-β-signalling and prevented lung fibrosis by decreasing the stability of Smad3 in an E3 ligase carboxy terminus of Hsc70-interacting protein-dependent manner. Moreover, CYLD decreases Smad3 stability by deubiquitinating K63-polyubiquitinated Akt. Together, our results unveil a role for CYLD in tightly regulating the resolution of lung injury and preventing fibrosis by deubiquitinating Akt. These studies may help develop new therapeutic strategies for preventing lung fibrosis. PMID:22491319

  18. Transforming growth factor-beta induces loss of epithelial character and smooth muscle cell differentiation in epicardial cells.

    PubMed

    Compton, Leigh A; Potash, Dru A; Mundell, Nathan A; Barnett, Joey V

    2006-01-01

    During embryogenesis, epicardial cells undergo epithelial-mesenchymal transformation (EMT), invade the myocardium, and differentiate into components of the coronary vasculature, including smooth muscle cells. We tested the hypothesis that transforming growth factor-beta (TGFbeta) stimulates EMT and smooth muscle differentiation of epicardial cells. In epicardial explants, TGFbeta1 and TGFbeta2 induce loss of epithelial morphology, cytokeratin, and membrane-associated Zonula Occludens-1 and increase the smooth muscle markers calponin and caldesmon. Inhibition of activin receptor-like kinase (ALK) 5 blocks these effects, whereas constitutively active (ca) ALK5 increases cell invasion by 42%. Overexpression of Smad 3 did not mimic the effects of caALK5. Inhibition of p160 rho kinase or p38 MAP kinase prevented the loss of epithelial morphology in response to TGFbeta, whereas only inhibition of p160 rho kinase blocked TGFbeta-stimulated caldesmon expression. These data demonstrate that TGFbeta stimulates loss of epithelial character and smooth muscle differentiation in epicardial cells by means of a mechanism that requires ALK5 and p160 rho kinase. PMID:16258965

  19. Liver Failure Impairs the Intrahepatic Elimination of Interleukin-6, Tumor Necrosis Factor-Alpha, Hepatocyte Growth Factor, and Transforming Growth Factor-Beta.

    PubMed

    Porowski, Dawid; Wirkowska, Agnieszka; Hryniewiecka, Ewa; Wyzgał, Janusz; Pacholczyk, Marek; Pączek, Leszek

    2015-01-01

    The strategic location of the liver and its metabolic activity make it a key organ regulating homeostasis. Our purpose was to examine its participation in removal of cytokines: interleukin-6 (Il-6), tumor necrosis factor-alpha (TNF-α), hepatocyte growth factor (HGF), and transforming growth factor-beta (TGF-β) from the portal circulation in human. 20 liver donors and 20 patients with end-stage liver failure were included in the study. Their blood was collected during liver transplantation from the portal, hepatic, and peripheral vein, and the hepatic artery and cytokines' concentrations were determined. Using the results the mathematical model of cytokine elimination by the liver was developed. In donors significantly lower levels of IL-6, TNF-α, HGF, and TGF-β were detected in portal blood compared to hepatic vein. In patients with cirrhosis there were no significant differences of IL-6, TNF-α, and TGF-β levels between portal and hepatic veins. Significantly higher level of HGF in hepatic compared to portal vein was observed. In healthy liver elimination of the cytokines prevailed over their synthesis, as reflected by the positive values of the elimination ratios. In the cirrhotic liver elimination ratios of Il-6, HGF, and TGF-β were negative indicating the prevalence of intrahepatic synthesis of cytokines over their removal. PMID:26090463

  20. Growth differentiation factor 11 signals through the transforming growth factor-beta receptor ALK5 to regionalize the anterior-posterior axis.

    PubMed

    Andersson, Olov; Reissmann, Eva; Ibáñez, Carlos F

    2006-08-01

    Growth differentiation factor 11 (GDF11) contributes to regionalize the mouse embryo along its anterior-posterior axis by regulating the expression of Hox genes. The identity of the receptors that mediate GDF11 signalling during embryogenesis remains unclear. Here, we show that GDF11 can interact with type I receptors ALK4, ALK5 and ALK7, but predominantly uses ALK4 and ALK5 to activate a Smad3-dependent reporter gene. Alk5 mutant embryos showed malformations in anterior-posterior patterning, including the lack of expression of the posterior determinant Hoxc10, that resemble defects found in Gdf11-null mutants. A heterozygous mutation in Alk5, but not in Alk4 or Alk7, potentiated Gdf11(-/-)-like phenotypes in vertebral, kidney and palate development in an Acvr2b(-/-) background, indicating a genetic interaction between the two receptor genes. Thus, the transforming growth factor-beta (TGF-beta) receptor ALK5, which until now has only been associated with the biological functions of TGF-beta1 to TGF-beta3 proteins, mediates GDF11 signalling during embryogenesis. PMID:16845371

  1. Transforming growth factor-β1 and cigarette smoke inhibit the ability of β2-agonists to enhance epithelial permeability.

    PubMed

    Unwalla, Hoshang J; Ivonnet, Pedro; Dennis, John S; Conner, Gregory E; Salathe, Matthias

    2015-01-01

    Chronic bronchitis, caused by cigarette smoke exposure, is characterized by mucus hypersecretion and reduced mucociliary clearance (MCC). Effective MCC depends, in part, on adequate airway surface liquid. Cystic fibrosis transmembrane conductance regulator (CFTR) provides the necessary osmotic gradient for serosal to mucosal fluid transport through its ability to both secrete Cl(-) and regulate paracellular permeability, but CFTR activity is attenuated in chronic bronchitis and in smokers. β2-adrenergic receptor (β2-AR) agonists are widely used for managing chronic obstructive pulmonary disease, and can activate CFTR, stimulate ciliary beat frequency, and increase epithelial permeability, thereby stimulating MCC. Patients with chronic airway diseases and cigarette smokers demonstrate increased transforming growth factor (TGF)-β1 signaling, which suppresses β2-agonist-mediated CFTR activation and epithelial permeability increases. Restoring CFTR function in these diseases can restore the ability of β2-agonists to enhance epithelial permeability. Human bronchial epithelial cells, fully redifferentiated at the air-liquid interface, were used for (14)C mannitol flux measurements, Ussing chamber experiments, and quantitative RT-PCR. β2-agonists enhance epithelial permeability by activating CFTR via the β2-AR/adenylyl cyclase/cAMP/protein kinase A pathway. TGF-β1 inhibits β2-agonist-mediated CFTR activation and epithelial permeability enhancement. Although TGF-β1 down-regulates both β2-AR and CFTR mRNA, functionally it only decreases CFTR activity. Cigarette smoke exposure inhibits β2-agonist-mediated epithelial permeability increases, an effect reversed by blocking TGF-β signaling. β2-agonists enhance epithelial permeability via CFTR activation. TGF-β1 signaling inhibits β2-agonist-mediated CFTR activation and subsequent increased epithelial permeability, potentially limiting the ability of β2-agonists to facilitate paracellular transport in disease

  2. Transforming Growth Factor-β1 and Cigarette Smoke Inhibit the Ability of β2-Agonists to Enhance Epithelial Permeability

    PubMed Central

    Ivonnet, Pedro; Dennis, John S.; Conner, Gregory E.; Salathe, Matthias

    2015-01-01

    Chronic bronchitis, caused by cigarette smoke exposure, is characterized by mucus hypersecretion and reduced mucociliary clearance (MCC). Effective MCC depends, in part, on adequate airway surface liquid. Cystic fibrosis transmembrane conductance regulator (CFTR) provides the necessary osmotic gradient for serosal to mucosal fluid transport through its ability to both secrete Cl− and regulate paracellular permeability, but CFTR activity is attenuated in chronic bronchitis and in smokers. β2-adrenergic receptor (β2-AR) agonists are widely used for managing chronic obstructive pulmonary disease, and can activate CFTR, stimulate ciliary beat frequency, and increase epithelial permeability, thereby stimulating MCC. Patients with chronic airway diseases and cigarette smokers demonstrate increased transforming growth factor (TGF)-β1 signaling, which suppresses β2-agonist–mediated CFTR activation and epithelial permeability increases. Restoring CFTR function in these diseases can restore the ability of β2-agonists to enhance epithelial permeability. Human bronchial epithelial cells, fully redifferentiated at the air–liquid interface, were used for 14C mannitol flux measurements, Ussing chamber experiments, and quantitative RT-PCR. β2-agonists enhance epithelial permeability by activating CFTR via the β2-AR/adenylyl cyclase/cAMP/protein kinase A pathway. TGF-β1 inhibits β2-agonist–mediated CFTR activation and epithelial permeability enhancement. Although TGF-β1 down-regulates both β2-AR and CFTR mRNA, functionally it only decreases CFTR activity. Cigarette smoke exposure inhibits β2-agonist–mediated epithelial permeability increases, an effect reversed by blocking TGF-β signaling. β2-agonists enhance epithelial permeability via CFTR activation. TGF-β1 signaling inhibits β2-agonist–mediated CFTR activation and subsequent increased epithelial permeability, potentially limiting the ability of β2-agonists to facilitate paracellular transport in

  3. The fungal metabolite gliotoxin inhibits proteasome proteolytic activity and induces an irreversible pseudocystic transformation and cell death in Tritrichomonas foetus.

    PubMed

    Pereira-Neves, Antonio; Menna-Barreto, Rubem F S; Benchimol, Marlene

    2016-08-01

    Proteasomal proteolysis is required for a wide range of cellular processes, including protein quality control, cell cycle progression, cell death and metabolic adaptation to environment changes or stress responses. Proteasome inhibitors are useful compounds for determining the roles of proteasome in eukaryotic cells. Here, we investigated the effects of gliotoxin, a proteasome inhibitor, on the cell growth, replication, ultrastructure, DNA integrity and proteasomal proteolytic activity of the protist parasite Tritrichomonas foetus. The effect of gliotoxin on the transformation of T. foetus to endoflagellar form (EFF), also known as pseudocyst, was investigated. Gliotoxin inhibited the culture growth, arrested cell cycle, and provoked a trichomonacidal effect in a dose-dependent manner. Parasites treated with gliotoxin displayed features typical of cell death, such as membrane blebbing, concentric membrane whorls containing remnants of organelles, intense cytosolic and nuclear vacuolisation, chromatin condensation, DNA fragmentation, cytoplasmic disintegration and plasma membrane disruption. The proteasomal peptidase activity was inhibited by gliotoxin in a dose-dependent manner. Gliotoxin treatment also induced an irreversible EFF transformation in a dose/time-dependent manner. We compared morphological characteristics between gliotoxin- and cold-induced EFF parasites. Our results suggest that gliotoxin could induce EFF transformation by a mechanism distinct from that provoked by cold temperature. This study further contributes to a better understanding of the role of proteasome system in cell cycle, cell death and EFF transformation in T. foetus. PMID:27106236

  4. Transforming growth factor-alpha promotes mammary tumorigenesis through selective survival and growth of secretory epithelial cells.

    PubMed Central

    Smith, G. H.; Sharp, R.; Kordon, E. C.; Jhappan, C.; Merlino, G.

    1995-01-01

    Transforming growth factor (TGF)-alpha stimulates the growth and development of mammary epithelial cells and is implicated in the pathogenesis of human breast cancer. In this report we evaluate the consequences of overexpressing TGF-alpha in the mammary gland of transgenic mice and examine associated cellular mechanisms. When operating on a FVB/N genetic background (line MT100), TGF-alpha induced the stochastic development of mammary adenomas and adenocarcinomas f secretory epithelial origin in 64% of multiparous females. In contrast, tumors were exceedingly rare in virgin MT100 females, MT100 males, and multiparous FVB/N females. In MT100 females multiple foci of hyperplastic secretory lesions preceded the development of frank tumors; these initial lesions appeared during the involution period after the first lactation. Serial transplantation of these hyperplasias indicated an absence of proliferative immortality. Nevertheless, they gave rise to tumors at a low frequency and after a prolonged latency in virgin hosts; in multiparous hosts, tumors developed earlier and at a high incidence. The TGF-alpha transgene was highly expressed in hyperplasias and tumors but not in virgin and nonlesion-bearing tissue, suggesting that TGF-alpha overexpression provides a selective growth advantage. TGF-alpha also induced at lactation a 6.4-fold increase in DNA synthesis in MT100 epithelial cells, many of which were binucleated. MT100 mammary tissue experienced an obvious delay in involution, resulting in the postlactational survival of a significant population of unregressed secretory epithelial cells. In contrast, another line of transgenic mice on a CD-1 genetic background (MT42), in which TGF-alpha overexpression induced liver but not mammary tumors, failed to demonstrate postlactational epithelial cell survival. These data show that TGF-alpha promotes mammary tumorigenesis in multiparous MT100 mice by stimulating secretory epithelial cell proliferation during lactation and

  5. Expression and localization of epidermal growth factor, transforming growth factor-α and epidermal growth factor receptor in the canine testis

    PubMed Central

    TAMADA, Hiromichi; TAKEMOTO, Kohei; TOMINAGA, Masato; KAWATE, Noritoshi; TAKAHASHI, Masahiro; HATOYA, Shingo; MATSUYAMA, Satoshi; INABA, Toshio; SAWADA, Tsutomu

    2015-01-01

    Gene expression of epidermal growth factor (EGF), transforming growth factor-α (TGF-α) and EGF receptor (EGF-R) and the localization of the corresponding proteins in the canine testis were studied. Levels of mRNA expressions were determined by semiquantitative reverse transcription polymerase chain reaction in the testes of the peripubertal (4–6 months), young adult (3–4 years), advanced adult (7–8 years) and senescent (11–16 years) groups. The EGF-R mRNA level in the testes of the peripubertal group was significantly higher than those in the other groups, whereas there was no difference in EGF and TGF-α mRNA levels among groups. Immunohistochemical stainings for EGF, TGF-α and EGF-R in the testis revealed that immunoreactivity in the seminiferous epithelium and Sertoli cell was weak and nonspecific for the stage of spermatogenesis, and distinct staining was found in Leydig cells. These results suggest that the EGF family of growth factors may be involved in testicular maturation and function in the dog. PMID:26498203

  6. Inhibition of Transforming Growth Factor-{beta} Signaling in Normal Lung Epithelial Cells Confers Resistance to Ionizing Radiation

    SciTech Connect

    Reeves, Anna; Zagurovskaya, Marianna; Gupta, Seema; Shareef, Mohammed M.; Mohiuddin, Mohammed; Ahmed, Mansoor M. . E-mail: mmahmed@geisinger.edu

    2007-05-01

    Purpose: To address the functional role of radiation-induced transforming growth factor-{beta} (TGF-{beta}) signaling in a normal epithelial background, we selected a spontaneously immortalized lung epithelial cell line derived from the normal lung tissue of a dominant-negative mutant of the TGF-{beta} RII ({delta}RII) transgenic mouse that conditionally expressed {delta}RII under the control of the metallothionein promoter (MT-1), and assessed this cell line's response to radiation. Methods and Materials: A spontaneously immortalized lung epithelial cell culture (SILECC) was established and all analyses were performed within 50 passages. Colony-forming and terminal transferase dUPT nick end labeling (TUNEL) assays were used to assess clonogenic inhibition and apoptosis, respectively. Western-blot analysis was performed to assess the kinetics of p21, bax, and RII proteins. Transforming growth factor-{beta}-responsive promoter activity was measured using dual-luciferase reporter assay. Results: Exposure to ZnSO{sub 4} inhibited TGF-{beta} signaling induced either by recombinant TGF-{beta}1 or ionizing radiation. The SILECC, treated with either ZnSO{sub 4} or neutralizing antibody against TGF-{beta}, showed a significant increase in radio-resistance compared to untreated cells. Furthermore, the expression of {delta}RII inhibited the radiation-induced up-regulation of the TGF-{beta} effector gene p21{sup waf1/cip1}. Conclusions: Our findings imply that inhibition of radiation-induced TGF-{beta} signaling via abrogation of the RII function enhances the radio-resistance of normal lung epithelial cells, and this can be directly attributed to the loss of TGF-{beta} signaling function.

  7. Cementogenesis and the induction of periodontal tissue regeneration by the osteogenic proteins of the transforming growth factor-beta superfamily.

    PubMed

    Ripamonti, U; Petit, J-C; Teare, J

    2009-04-01

    The antiquity and severity of periodontal diseases are demonstrated by the hard evidence of alveolar bone loss in gnathic remains of the Pliocene/Pleistocene deposits of the Bloubank Valley at Sterkfontein, Swartkrans and Kromdrai in South Africa. Extant Homo has characterized and cloned a superfamily of proteins which include the bone morphogenetic proteins that regulate tooth morphogenesis at different stages of development as temporally and spatially connected events. The induction of cementogenesis, periodontal ligament and alveolar bone regeneration are regulated by the co-ordinated expression of bone morphogenetic proteins. Naturally derived and recombinant human bone morphogenetic proteins induce periodontal tissue regeneration in mammals. Morphological analyses on undecalcified sections cut at 3-6 mum on a series of mandibular molar Class II and III furcation defects induced in the non-human primate Papio ursinus show the induction of cementogenesis. Sharpey's fibers nucleate as a series of composite collagen bundles within the cementoid matrix in close relation to embedded cementocytes. Osteogenic protein-1 and bone morphogenetic protein-2 possess a structure-activity profile, as shown by the morphology of tissue regeneration, preferentially cementogenic and osteogenic, respectively. In Papio ursinus, transforming growth factor-beta(3) also induces cementogenesis, with Sharpey's fibers inserting into newly formed alveolar bone. Capillary sprouting and invasion determine the sequential insertion and alignment of individual collagenic bundles. The addition of responding stem cells prepared by finely mincing fragments of autogenous rectus abdominis muscle significantly enhances the induction of periodontal tissue regeneration when combined with transforming growth factor-beta(3) implanted in Class II and III furcation defects of Papio ursinus. PMID:18842117

  8. Interrelationship of in situ growth stress evolution and phase transformations in Ti/W multilayered thin films

    NASA Astrophysics Data System (ADS)

    Wan, Li; Yu, Xiao-xiang; Zhou, Xuyang; Thompson, Gregory

    2016-06-01

    This paper addresses the in situ growth stress evolution and phase transformation of bcc to hcp Ti in Ti/W multilayered thin films. A series of equal layer thicknesses from 20 nm to 1 nm were deposited. As the bilayer thickness reduced, the overall film stress became less compressive until the Ti transformed from hcp (at the larger layer thicknesses) to bcc in the 1 nm/1 nm multilayer. The pseudomorphic bcc stabilization resulted in a recovery of the compressive stress to values near that for the bulk phase stabilized for the 5 nm/5 nm multilayer. A discernable change in stress slope was noted for the bcc to hcp Ti transition as a function of Ti layer thickness. The stress states for each film, during film growth, are rationalized by the lattice matching of the phase with the growth surface. These results are coupled to a molecular dynamics deposition simulation which revealed good agreement with the experimentally observed transformation thickness.

  9. Opposing oncogenic activities of small DNA tumor virus transforming proteins

    PubMed Central

    Chinnadurai, G.

    2011-01-01

    The E1A gene of species C human adenovirus is an intensely investigated model viral oncogene that immortalizes primary cells and mediates oncogenic cell transformation in cooperation with other viral or cellular oncogenes. Investigations using E1A proteins have illuminated important paradigms in cell proliferation and the functions of cellular proteins such as the retinoblastoma protein. Studies with E1A have led to the surprising discovery that E1A also suppresses cell transformation and oncogenesis. Here, I review our current understanding of the transforming and tumor suppressive functions of E1A, and how E1A studies led to the discovery of a related tumor suppressive function in benign human papillomaviruses. The potential role of these opposing functions in viral replication in epithelial cells is also discussed. PMID:21330137

  10. Transformational teaching and physical activity: a new paradigm for adolescent health promotion?

    PubMed

    Morton, K L; Keith, S E; Beauchamp, M R

    2010-03-01

    Drawing from transformational leadership theory, this research examined adolescent perceptions of transformational teaching within school-based physical education. In Study 1, focus groups with 62 adolescents examined perceptions of physical education teachers' behaviors. In Study 2, follow-up semi-structured interviews were conducted with 18 purposively sampled students. Findings revealed that behaviors within physical education settings can be understood within a conceptual framework that includes transformational teaching. In addition, students who perceived their teachers to utilize transformational behaviors described more adaptive responses. Issues concerning theory development and the application of transformational teaching to physical activity and health promotion settings are considered. PMID:20207668

  11. A Histologically Distinctive Interstitial Pneumonia Induced by Overexpression of the Interleukin 6, Transforming Growth Factor β1, or Platelet-Derived Growth Factor B Gene

    NASA Astrophysics Data System (ADS)

    Yoshida, Mitsuhiro; Sakuma, Junko; Hayashi, Seiji; Abe, Kin'ya; Saito, Izumu; Harada, Shizuko; Sakatani, Mitsunoir; Yamamoto, Satoru; Matsumoto, Norinao; Kaneda, Yasufumi; Kishmoto, Tadamitsu

    1995-10-01

    Interstitial pneumonia is characterized by alveolitis with resulting fibrosis of the interstitium. To determine the relevance of humoral factors in the pathogenesis of interstitial pneumonia, we introduced expression vectors into Wistar rats via the trachea to locally overexpress humoral factors in the lungs. Human interleukin (IL) 6 and IL-6 receptor genes induced lymphocytic alveolitis without marked fibroblast proliferation. In contrast, overexpression of human transforming growth factor β1 or human platelet-derived growth factor B gene induced only mild or apparent cellular infiltration in the alveoli, respectively. However, both factors induced significant proliferation of fibroblasts and deposition of collagen fibrils. These histopathologic changes induced by the transforming growth factor β1 and platelet-derived growth factor B gene are partly akin to those changes seen in lung tissues from patients with pulmonary fibrosis and markedly contrast with the changes induced by overexpression of the IL-6 and IL-6 receptor genes that mimics lymphocytic interstitial pneumonia.

  12. Transforming growth factor-{beta}2 enhances differentiation of cardiac myocytes from embryonic stem cells

    SciTech Connect

    Kumar, Dinender . E-mail: Dinender.Kumar@uvm.edu; Sun, Baiming

    2005-06-24

    Stem cell therapy holds great promise for the treatment of injured myocardium, but is challenged by a limited supply of appropriate cells. Three different isoforms of transforming growth factor-{beta} (TGF-{beta}) -{beta}1, -{beta}2, and -{beta}3 exhibit distinct regulatory effects on cell growth, differentiation, and migration during embryonic development. We compared the effects of these three different isoforms on cardiomyocyte differentiation from embryonic stem (ES) cells. In contrast to TGF-{beta}1, or -{beta}3, treatment of mouse ES cells with TGF-{beta}2 isoform significantly increased embryoid body (EB) proliferation as well as the extent of the EB outgrowth that beat rhythmically. At 17 days, 49% of the EBs treated with TGF-{beta}2 exhibited spontaneous beating compared with 15% in controls. Cardiac myocyte specific protein markers sarcomeric myosin and {alpha}-actin were demonstrated in beating EBs and cells isolated from EBs. In conclusion, TGF-{beta}2 but not TGF-{beta}1, or -{beta}3 promotes cardiac myocyte differentiation from ES cells.

  13. Melanoma-associated expression of transforming growth factor-beta isoforms.

    PubMed Central

    Van Belle, P.; Rodeck, U.; Nuamah, I.; Halpern, A. C.; Elder, D. E.

    1996-01-01

    Melanocytic neoplasia is characterized by the aberrant overproduction of multiple cytokines in vitro. However, it is largely unknown how cytokine expression relates to melanoma progression in vivo. Transforming growth factor beta (TGF-beta) is a multifunctional cytokine commonly produced by cultured melanoma cells. The in situ expression of all three TGF-beta isoforms (TGF-beta1, -2, and -3) was determined immunohistochemically in melanocytes and in 51 melanocytic lesions using isoform-specific antibodies. Significant linear trends of expression were observed from melanocytes through nevi and primary and metastatic melanomas for all three isoforms. TGF-beta1 was expressed by some melanocytes and almost uniformly by nevi and melanomas. TGF-beta2 and -3 were not expressed in normal melanocytes but were expressed in nevi and early and advanced primary (radial and vertical growth phase) and metastatic melanomas in a tumor-progression-related manner. TGF-beta2 was heterogeneously expressed in advanced primary and metastatic melanomas, whereas TGF-beta3 was uniformly and highly expressed in these lesions. Thus, expression of TGF-beta isoforms in melanocytes and melanocytic lesions is heterogeneous and related to tumor progression, and expression of TGF-beta2 and TGF-beta3 commences at critical junctures during progression of nevi to primary melanomas. Images Figure 2 Figure 3 PMID:8669474

  14. Changes in Maternal Serum Transforming Growth Factor Beta-1 during Pregnancy: A Cross-Sectional Study

    PubMed Central

    Orazulike, Ngozi C.; Ashmore, Jill; Konje, Justin C.

    2013-01-01

    Changes in circulating levels of maternal serum transforming growth factor beta-1 (TGF-β1), collected from 98 women (AGA) at different gestational ages (10–38 weeks) were measured and comparisons were made between levels in pregnant and nonpregnant controls and also between 10 women with small-for-gestational age (SGA) and 7 with appropriate-for-gestational age (AGA) fetuses. Maternal serum TGF-β1 levels at all stages of pregnancy were higher than those in normal healthy nonpregnant adults. The mean TGF-β1 levels in SGA pregnancies at 34-week gestation (32.5 + 3.2 ng/mL) were significantly less than those in AGA pregnancies (39.2 + 9.8 ng/mL) while at 38-week gestation, the levels were similar in the two groups (36.04 + 4.3 versus 36.7 + 7.0 ng/mL). This differential change in TGF-β1 levels is probably an important modulating factor in the aetiopathogenesis of abnormal intrauterine fetal growth. PMID:24350258

  15. Altered expression of transforming growth factor-beta isoforms in bovine cystic ovarian disease.

    PubMed

    Matiller, V; Stangaferro, M L; Díaz, P U; Ortega, H H; Rey, F; Huber, E; Salvetti, N R

    2014-10-01

    Cystic ovarian disease (COD) is one of the main causes of infertility in dairy cattle. It has been shown that intra-ovarian factors may contribute to follicular persistence. Transforming growth factor-beta (TGFB) isoforms are important paracrine and autocrine signalling molecules that regulate ovarian follicle growth and physiology. Considering the importance of these factors in the ovarian physiology, in this study, we examined the expression of TGFB isoforms (TGFB1, TGFB2 and TGFB3) in the ovary of healthy cows and animals with spontaneous and adrenocorticotrophic hormone (ACTH)-induced COD. In the oestrous-synchronized control group, the expression of TGFB1 in granulosa and theca cells was higher in spontaneous cysts than in atretic or tertiary follicles. When we compared TGFB2 expression in granulosa cells from atretic or tertiary follicles from the oestrous-synchronized control group with that in ACTH-induced or spontaneous follicular cysts, we found a higher expression in the latter. The expression of the TGFB isoforms studied was also altered during folliculogenesis in both the spontaneous and ACTH-induced COD groups. As it has been previously shown that TGFB influences steroidogenesis, ovarian follicular proliferation and apoptosis, an alteration in its expression may contribute to the pathogenesis of this disease. PMID:25112788

  16. Down-regulated expression of transforming growth factor beta 1 mRNA in endometrial carcinoma.

    PubMed Central

    Perlino, E.; Loverro, G.; Maiorano, E.; Giannini, T.; Cazzolla, A.; Napoli, A.; Fiore, M. G.; Ricco, R.; Marra, E.; Selvaggi, L.

    1998-01-01

    Transforming growth factor beta1 (TGF-beta1) is a potent modulator of cell proliferation in vitro, and recent studies have demonstrated its overexpression in several different tumours; nevertheless, the molecular mechanisms of TGF-beta1 action on cell growth and differentiation have not been fully elucidated. To clarify the role of TGF-beta and its receptor in human endometrial proliferation and differentiation, TGF-beta1 expression at both the mRNA and protein levels has been evaluated by using Northern blotting and immunohistochemistry, in both normal (atrophic, proliferative and secretory) and neoplastic (adenocarcinoma) endometrial samples. This study demonstrates that TGF-beta1 mRNA expression is dramatically reduced in endometrial carcinomas with respect to non-neoplastic tissues, whereas the immunohistochemical expression of TGF-beta1 is enhanced in the epithelial component of endometrial carcinomas compared with non-neoplastic tissues. These data suggest that TGF-beta1 acts as a paracrine regulator of endometrial cell proliferation and that it may contribute to the carcinogenic mechanisms of endometrial carcinoma. Images Figure 1 Figure 5 Figure 6 Figure 8 PMID:9579831

  17. Down-regulated expression of transforming growth factor beta 1 mRNA in endometrial carcinoma.

    PubMed

    Perlino, E; Loverro, G; Maiorano, E; Giannini, T; Cazzolla, A; Napoli, A; Fiore, M G; Ricco, R; Marra, E; Selvaggi, L

    1998-04-01

    Transforming growth factor beta1 (TGF-beta1) is a potent modulator of cell proliferation in vitro, and recent studies have demonstrated its overexpression in several different tumours; nevertheless, the molecular mechanisms of TGF-beta1 action on cell growth and differentiation have not been fully elucidated. To clarify the role of TGF-beta and its receptor in human endometrial proliferation and differentiation, TGF-beta1 expression at both the mRNA and protein levels has been evaluated by using Northern blotting and immunohistochemistry, in both normal (atrophic, proliferative and secretory) and neoplastic (adenocarcinoma) endometrial samples. This study demonstrates that TGF-beta1 mRNA expression is dramatically reduced in endometrial carcinomas with respect to non-neoplastic tissues, whereas the immunohistochemical expression of TGF-beta1 is enhanced in the epithelial component of endometrial carcinomas compared with non-neoplastic tissues. These data suggest that TGF-beta1 acts as a paracrine regulator of endometrial cell proliferation and that it may contribute to the carcinogenic mechanisms of endometrial carcinoma. PMID:9579831

  18. c-Jun N-terminal kinase inhibitor favors transforming growth factor-β to antagonize hepatitis B virus X protein-induced cell growth promotion in hepatocellular carcinoma

    PubMed Central

    WU, YAN-HUI; AI, XI; LIU, FU-YAO; LIANG, HUI-FANG; ZHANG, BI-XIANG; CHEN, XIAO-PING

    2016-01-01

    Transforming growth factor (TGF)-β induces cell growth arrest in well-differentiated hepatocellular carcinoma (HCC) while hepatitis B virus X protein (HBx) minimizes the tumor suppression of TGF-β signaling in early chronic hepatitis B. However, how to reverse the oncogenic effect of HBx and sustain the tumor-suppressive action of TGF-β has yet to be investigated. The present study examined the effect of TGF-β and a c-Jun N-terminal kinase (JNK) inhibitor on cell growth in HCC cells with forced expression of HBx. It was found that HBx promoted cell growth via activation of the JNK/pSMAD3L pathway and inhibition of the transforming growth factor-beta type I receptor (TβRI)/pSMAD3C pathway. pSMAD3L/SMAD4 and pSMAD3C/SMAD4 complexes antagonized each other to regulate c-Myc expression. In the absence of HBx, TGF-β induced cell growth arrest through activation of the TβRI/pSMAD3C pathway in well-differentiated HCC cells. In the presence of HBx, TGF-β had no effect on cell growth. JNK inhibitor SP600125 significantly reversed the oncogenic action of HBx and favored TGF-β to regain the ability to inhibit the cell growth in HBx-expressing well-differentiated HCC cells. In conclusion, targeting JNK signaling favors TGF-β to block HBx-induced cell growth promotion in well-differentiated HCC cells. As an adjunct to anti-viral therapy, the combination of TGF-β and inhibition of JNK signaling is a potential therapy for HBV-infected HCC. PMID:26648552

  19. Abrogation of growth arrest signals by human papillomavirus type 16 E7 is mediated by sequences required for transformation.

    PubMed Central

    Demers, G W; Espling, E; Harry, J B; Etscheid, B G; Galloway, D A

    1996-01-01

    Cells arrest in the G1 or G0 phase of the cell cycle in response to a variety of negative growth signals that induce arrest by different molecular pathways. The ability of human papillomavirus (HPV) oncogenes to bypass these signals and allow cells to progress into the S phase probably contributes to the neoplastic potential of the virus. The E7 protein of HPV-16 was able to disrupt the response of epithelial cells to three different negative growth arrest signals: quiescence imposed upon suprabasal epithelial cells, G1 arrest induced by DNA damage, and inhibition of DNA synthesis caused by treatment with transforming growth factor beta. The same set of mutated E7 proteins was able to abrogate all three growth arrest signals. Mutant proteins that failed to abrogate growth arrest signals were transformation deficient and included E7 proteins that bound retinoblastoma protein in vitro. In contrast, HPV-16 E6 was able to bypass only DNA damage-induced G1 arrest, not suprabasal quiescence or transforming growth factor beta-induced arrest. The E6 and E7 proteins from the low-risk virus HPV-6 were not able to bypass any of the growth arrest signals. PMID:8794328

  20. Role and mechanism of miR-222 in arsenic-transformed cells for inducing tumor growth

    PubMed Central

    Wang, Min; Li, Dongmei; Liu, Xue; Wang, Lin; Jiang, Chengfei; Shi, Zhumei; Qin, Lianju; Liu, Jiayin; Yang, Hushan; Liu, Ling-Zhi; He, Jun; Zhen, Linlin; Jiang, Bing-Hua

    2016-01-01

    High levels of arsenic in drinking water, soil, and air are associated with the higher incidences of several kinds of cancers worldwide, but the mechanism is yet to be fully discovered. Recently, a number of evidences show that dysregulation of microRNAs (miRNAs) induces carcinogenesis. In this study, we found miR-222 was upregulated in arsenic-transformed human lung epithelial BEAS-2B cells (As-T cells). Anti-miR-222 inhibitor treatment decreased cell proliferation, migration, tube formation, and induced apoptosis. In addition, anti-miR-222 inhibitor expression decreased tumor growth in vivo. We also found that inhibition of miR-222 induced the expression of its direct targets ARID1A and phosphatase and tensin homolog deleted on chromosome 10 (PTEN), and activated apoptosis of As-T cells in part through ARID1A downregulation. These results indicate that miR-222 plays an important role in arsenic-induced tumor growth. PMID:26909602

  1. Active Learning in the Workplace: Transforming Individuals and Institutions

    ERIC Educational Resources Information Center

    Pare, Anthony; Le Maistre, Cathrine

    2006-01-01

    In order to keep current and dynamic, organizations depend on the careful induction of new members. In social work, as in many professions, that task is generally given to experienced practitioners who supervise and manage the gradual transformation of novices into effective professionals. The process is critical for both organizations and…

  2. TRANSFORMING GROWTH FACTOR-BETA MEDIATED SUPPRESSION OF ANTI-TUMOR T CELLS REQUIRES FOXP1 TRANSCRIPTION FACTOR EXPRESSION

    PubMed Central

    Stephen, Tom L.; Rutkowski, Melanie R.; Allegrezza, Michael J.; Perales-Puchalt, Alfredo; Tesone, Amelia J.; Svoronos, Nikolaos; Nguyen, Jenny M.; Sarmin, Fahmida; Borowsky, Mark E.; Tchou, Julia; Conejo-Garcia, Jose R.

    2014-01-01

    SUMMARY Tumor-reactive T cells become unresponsive in advanced tumors. Here we have characterized a common mechanism of T cell unresponsiveness in cancer driven by the up-regulation of the transcription factor Forkhead box protein P1 (Foxp1), which prevents CD8+ T cells from proliferating and up-regulating Granzyme-B and interferon-γ (IFN-γ) in response to tumor antigens. Accordingly, Foxp1-deficient lymphocytes induced rejection of incurable tumors, and promoted protection against tumor re-challenge. Mechanistically, Foxp1 interacted with the transcription factors Smad2 and Smad3 in pre-activated CD8+ T cells in response to microenvironmental transforming growth factor-β (TGF-β), and was essential for its suppressive activity. Therefore, Smad2 and Smad3-mediated c-Myc repression requires Foxp1 expression in T cells. Furthermore, Foxp1 directly mediated TGF-β-induced c-Jun transcriptional repression, which abrogated T cell activity. Our results unveil a fundamental mechanism of T cell unresponsiveness different from anergy or exhaustion, driven by TGF-β signaling on tumor-associated lymphocytes undergoing Foxp1-dependent transcriptional regulation. PMID:25238097

  3. Transforming growth factor beta 1 and beta 2 induce down-modulation of thrombomodulin in human umbilical vein endothelial cells.

    PubMed

    Ohji, T; Urano, H; Shirahata, A; Yamagishi, M; Higashi, K; Gotoh, S; Karasaki, Y

    1995-05-01

    To investigate the effects of transforming growth factor-betas (TGF-betas) on endothelial anticoagulant activity, we assayed thrombomodulin (TM) activity and antigen levels of human umbilical vein endothelial cells (HUVECs) incubated with TGF-betas in vitro. TGF-beta 1 suppressed surface TM activity and surface TM antigen levels maximally 12 h after incubation in dose-dependent manners. TGF-beta 2 was almost equipotent with TGF-beta 1 for the suppression of them. Both TGF-betas suppressed total TM antigen level in HUVECs, and the time course of the suppression was similar to that of the cell surface TM antigen level. The maximal reductions of TM mRNA levels by TGF-betas were observed at several hours ahead of those observed in both surface and total TM antigens levels, suggesting that the TGF-beta-mediated suppression of TM antigen of HUVECs is primarily regulated at the TM mRNA level. Our present work suggests that the down-modulation of TM level induced by TGF-betas in HUVECs contributes in vivo to promoting the thrombogenesis either at the sites of injury of vessel walls, such as atherosclerotic lesions where TGF-beta 1 is released from platelets, smooth muscle cells and monocytes, or at neovascular walls in tumors secreting TGF-beta 2. PMID:7482408

  4. Dynamics of Transforming Growth Factor Beta Signaling in Wound Healing and Scarring

    PubMed Central

    Finnson, Kenneth W.; McLean, Sarah; Di Guglielmo, Gianni M.; Philip, Anie

    2013-01-01

    Significance Wound healing is an intricate biological process in which the skin, or any other tissue, repairs itself after injury. Normal wound healing relies on the appropriate levels of cytokines and growth factors to ensure that cellular responses are mediated in a coordinated manner. Among the many growth factors studied in the context of wound healing, transforming growth factor beta (TGF-β) is thought to have the broadest spectrum of effects. Recent Advances Many of the molecular mechanisms underlying the TGF-β/Smad signaling pathway have been elucidated, and the role of TGF-β in wound healing has been well characterized. Targeting the TGF-β signaling pathway using therapeutic agents to improve wound healing and/or reduce scarring has been successful in pre-clinical studies. Critical Issues Although TGF-β isoforms (β1, β2, β3) signal through the same cell surface receptors, they display distinct functions during wound healing in vivo through mechanisms that have not been fully elucidated. The challenge of translating preclinical studies targeting the TGF-β signaling pathway to a clinical setting may require more extensive preclinical research using animal models that more closely mimic wound healing and scarring in humans, and taking into account the spatial, temporal, and cell-type–specific aspects of TGF-β isoform expression and function. Future Directions Understanding the differences in TGF-β isoform signaling at the molecular level and identification of novel components of the TGF-β signaling pathway that critically regulate wound healing may lead to the discovery of potential therapeutic targets for treatment of impaired wound healing and pathological scarring. PMID:24527343

  5. Mesenchymal stem cells promote tumor angiogenesis via the action of transforming growth factor β1

    PubMed Central

    LI, GUO-CAI; ZHANG, HONG-WEI; ZHAO, QING-CHUN; SUN, LI; YANG, JIAN-JUN; HONG, LIU; FENG, FAN; CAI, LEI

    2016-01-01

    Mesenchymal stem cells (MSCs) may influence the growth and metastasis of various human malignancies, including hepatocellular carcinoma (HCC). Therefore, the underlying mechanisms via which MSCs are able to affect malignancies require investigation. In the present study, the potential role of MSC in the angiogenesis of HCC was investigated. A total of 17 nude mouse models exhibiting human HCC were used to evaluate the effects of MSC on angiogenesis. A total of 8 mice were injected with human MSCs via the tail vein, and the remaining 9 mice were injected with phosphate-buffered saline as a control. A total of 35 days subsequent to the injection of MSCs, the microvessel density (MVD) of tumors was evaluated by immunostaining, using cluster of differentiation 31 antibody. The mRNA levels of transforming growth factor (TGF)β1, Smad2 and Smad7 were detected using reverse transcription-quantitative polymerase chain reaction. Protein expression levels of TGFβ1 and vascular endothelial growth factor (VEGF) in tumor tissues were analyzed using ELISA. Compared with controls, MVD in MSC-treated mice was significantly increased (28.00±9.19 vs. 18.11±3.30; P=0.006). The levels of TGFβ1 mRNA in the MSC-treated group were 2.15-fold higher compared with the control group (1.27±0.61 vs. 0.59±0.39; P=0.033), and MVD was higher in the group exhibiting increased TGFβ1 mRNA levels compared with the control group (26.50±9.11 vs. 19.44±6.14; P=0.038). In addition, a close correlation between the expression levels of TGFβ1 and VEGF was identified. The results of the present study suggested that MSCs may be capable of enhancing the angiogenesis of HCC, which may be partly due to the involvement of TGFβ1. PMID:26893697

  6. Analysis of Epithelial-Mesenchymal Transition Induced by Transforming Growth Factor β.

    PubMed

    Valcourt, Ulrich; Carthy, Jonathon; Okita, Yukari; Alcaraz, Lindsay; Kato, Mitsuyasu; Thuault, Sylvie; Bartholin, Laurent; Moustakas, Aristidis

    2016-01-01

    In recent years, the importance of the cell biological process of epithelial-mesenchymal transition (EMT) has been established via an exponentially growing number of reports. EMT has been documented during embryonic development, tissue fibrosis, and cancer progression in vitro, in animal models in vivo and in human specimens. EMT relates to many molecular and cellular alterations that occur when epithelial cells undergo a switch in differentiation that generates mesenchymal-like cells with newly acquired migratory and invasive properties. In addition, EMT relates to a nuclear reprogramming similar to the one occurring in the generation of induced pluripotent stem cells. Via such a process, EMT is gradually established to promote the generation and maintenance of adult tissue stem cells which under disease states such as cancer, are known as cancer stem cells. EMT is induced by developmental growth factors, oncogenes, radiation, and hypoxia. A prominent growth factor that causes EMT is transforming growth factor β (TGF-β).A series of molecular and cellular techniques can be applied to define and characterize the state of EMT in diverse biological samples. These methods range from DNA and RNA-based techniques that measure the expression of key EMT regulators and markers of epithelial or mesenchymal differentiation to functional assays of cell mobility, invasiveness and in vitro stemness. This chapter focuses on EMT induced by TGF-β and provides authoritative protocols and relevant reagents and citations of key publications aiming at assisting newcomers that enter this prolific area of biomedical sciences, and offering a useful reference tool to pioneers and aficionados of the field. PMID:26520123

  7. Effect of transforming growth factor beta on synthesis of glycosaminoglycans by human lung fibroblasts

    SciTech Connect

    Dubaybo, B.A.; Thet, L.A. )

    1990-09-01

    The processes of lung growth, injury, and repair are characterized by alterations in fibroblast synthesis and interstitial distribution of extracellular matrix components. Transforming growth factor beta (TGF-beta), which is postulated to play a role in modulating lung repair, alters the distribution of several matrix components such as collagen and fibronectin. We studied the effect of TGF-beta on the synthesis and distribution of the various glycosaminoglycans (GAGs) and whether these effects may explain its role in lung repair. Human diploid lung fibroblasts (IMR-90) were exposed to various concentrations of TGF-beta (0-5 nM) for variable periods of time (0-18 h). Newly synthesized GAGs were labeled with either (3H)glucosamine or (35S)sulfate. Individual GAGs were separated by size exclusion chromatography after serial enzymatic and chemical digestions and quantitated using scintillation counting. There was a dose-dependent increase in total GAG synthesis with maximal levels detected after 6 h of exposure. This increase was noted in all individual GAG types measured and was observed in both the cell associated GAGs (cell-matrix fraction) as well as the GAGs released into the medium (medium fraction). In the cell-matrix fraction, TGF-beta increased the proportion of heparan sulfate that was membrane bound as well as the proportion of dermatan sulfate in the intracellular compartment. In the medium fraction, TGF-beta increased the proportion of hyaluronic acid, chondroitin sulfate and dermatan sulfate released. We conclude that the role of TGF-beta in lung growth and repair may be related to increased synthesis of GAGs by human lung fibroblasts as well as alterations in the distribution of individual GAGs.

  8. Growth and phase transformations: Insights from hydrothermal coarsening experiements using nanocrystalline titanium dioxide

    NASA Astrophysics Data System (ADS)

    Penn, Rona Lee

    Controlling the morphology and size of crystallizing materials is of special interest in Materials Science as particle morphology can affect many materials characteristics, including magnetism, reactivity, and densification. High-resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD) peak broadening (Scherrer) analysis, and determination of room temperature adsorption of organic acids by ion chromatography were used to study adsorption and hydrothermal coarsening and morphology development in nanocrystalline anatase (TiOsb2). HRTEM micrographs show that nanocrystalline anatase coarsens by two growth mechanisms: single crystal growth, via subnanometer-high surface steps, and a new growth mechanism known as oriented attachment, which involves topotactic joining of crystallites with subsequent coarsening to form single crystals of unique morphology. Addition of hydrochloric acid (pH = 3.0) to suspensions prior to hydrothermal treatment results in the formation of extremely elongate single crystals often comprised of more than 7 primary anatase crystallites. Both decreasing the pH of solutions below 3 and addition of organic acids resulted in a reduction in the frequency of observed attachments. Because attachment is only constrained by two dimensional match at the interface, attachment can lead to twinning and intergrowths on \\{112\\}, \\{101\\}, and (001). Slight misorientations between particles arising from surface topography at attaching surfaces, produces dislocations of edge, screw, and mixed character. Furthermore, anatase \\{112\\} twin boundaries consist of structural elements common to rutile and may serve as nucleation sites for the anatase-to-rutile transformation. These results have broad relevance for nucleation and growth models as they suggest that twinning, polytypism, and linear defects in macroscopic crystals can originate at oriented interfaces between primary nanocrystalline particles early in their crystallization history

  9. Rapamycin can restore the negative regulatory function of transforming growth factor beta 1 in high grade lymphomas.

    PubMed

    Sebestyén, Anna; Márk, Ágnes; Hajdu, Melinda; Nagy, Noémi; Molnár, Anna; Végső, Gyula; Barna, Gábor; Kopper, László

    2015-06-01

    TGF-β1 (transforming growth factor beta 1) is a negative regulator of lymphocytes, inhibiting proliferation and switching on the apoptotic program in normal lymphoid cells. Lymphoma cells often lose their sensitivity to proapoptotic/anti-proliferative regulators such as TGF-β1. Rapamycin can influence both mTOR (mammalian target of rapamycin) and TGF-β signaling, and through these pathways it is able to enhance TGF-β induced anti-proliferative and apoptotic responses. In the present work we investigated the effect of rapamycin and TGF-β1 combination on cell growth and on TGF-β and mTOR signalling events in lymphoma cells. Rapamycin, an inhibitor of mTORC1 (mTOR complex 1) did not elicit apoptosis in lymphoma cells; however, the combination of rapamycin with exogenous TGF-β1 induced apoptosis and restored TGF-β1 dependent apoptotic machinery in several lymphoma cell lines with reduced TGF-β sensitivity in vitro. In parallel, the phosphorylation of p70 ribosomal S6 kinase (p70S6K) and ribosomal S6 protein, targets of mTORC1, was completely eliminated. Knockdown of Smad signalling by Smad4 siRNA had no influence on apoptosis induced by the rapamycin+TGF-β1, suggesting that this effect is independent of Smad signalling. However, apoptosis induction was dependent on early protein phosphatase 2A (PP2A) activity, and in part on caspases. Rapamycin+TGF-β1 induced apoptosis was not completely eliminated by a caspase inhibitor. These results suggest that high mTOR activity contributes to TGF-β resistance and lowering mTORC1 kinase activity may provide a tool in high grade B-cell lymphoma therapy by restoring the sensitivity to normally available regulators such as TGF-β1. PMID:25794661

  10. Assessment of the frequency of the transforming growth factor beta-1 sequence polymorphisms in patients with alcohol dependence syndrome.

    PubMed

    Augustyńska, Beata; Araszkiewicz, Aleksander; Woźniak, Marcin; Grzybowski, Tomasz; Skonieczna, Katarzyna; Woźniak, Alina; Żyła, Magdalena

    2015-01-01

    Alcohol abuse is one of the most significant factors in the development of liver fibrosis. The pathomechanism of liver fibrosis is the same regardless of its etiology. Fibrosis is a sign of an imbalance between the synthesis of the extracellular matrix components and their degradation. Among the many cytokines that affect hepatic stellate cell activation it seems that transforming growth factor beta (TGF-β) is the most significant, either as the direct factor stimulating polymerase chain reaction (HSC) proliferation and transformation into myofibroblasts, or as the direct factor causing an increase in the activity of genes responsible for the synthesis of extracellular matrix components. The aim of the study was to reveal possible dependencies and differences between the presence of certain alleles of the TGF-β1 gene and its blood level in the study and control group. Blood samples were obtained from 39 patients, the control group consisted of 21 patients. The results obtained in the course of this study showed no statistically significant differences between the frequencies of particular polymorphisms. In the case of haplotype frequencies, insignificant differences were found for the algorithm Excoffier-Laval-Balding predicted haplotypes while one significant difference between the study and control groups was detected in case of the TC haplotype frequency predicted using the Expectation-Maximization algorithm. However, the difference in frequency of TC haplotype predicted by both algorithms was not significant. Genetic analysis of two single nucleotide polymorphisms (SNPs) in exon I of the TGF-β1 gene did not show significant differences between the occurrence of particular polymorphisms and haplotypes in the populations under study. PMID:25710054

  11. Insulin-like growth factor binding protein-2 mediates the inhibition of DNA synthesis by transforming growth factor-beta in mink lung epithelial cells.

    PubMed

    Dong, Feng; Wu, Hai-Bin; Hong, Jiang; Rechler, Matthew M

    2002-01-01

    Insulin-like growth factor binding protein-3 (IGFBP-3) has been proposed to mediate the growth inhibitory effects of transforming growth factor (TGF)-beta in breast and prostate cancer cells. Both TGF-beta and exogenous IGFBP-3 inhibit DNA synthesis in Mv1 mink lung epithelial cells (CCL64). The present study asks whether IGFBPs synthesized by CCL64 cells mediate growth inhibition by TGF-beta. CCL64 cells synthesize and secrete a single 34-kDa IGFBP that was identified as IGFBP-2 by immunoprecipitation and immunodepletion. Recombinant bovine IGFBP-2 inhibited CCL64 DNA synthesis in serum-free media in an IGF-independent manner. Coincubation with Leu(60)-IGF-I, an IGF-I analog that binds to IGFBPs with higher affinity than to IGF-I receptors, decreased the inhibition by bIGFBP-2. Leu(60)-IGF-I also decreased the inhibition of CCL64 DNA synthesis by TGF-beta by up to 70%, whereas Long-R3-IGF-I, an IGF-I analog with higher affinity for IGF-I receptors than for IGFBPs, did not decrease inhibition, suggesting that the effect of Leu(60)-IGF-I resulted from its forming complexes with endogenous IGFBPs. Leu(60)-IGF-I did not decrease TGF-beta stimulation of a Smad3-dependent reporter gene. Following incubation of intact CCL64 cells with bIGFBP-2 at 0 degrees C, bIGFBP-2 was recovered in membrane fractions; membrane association was abolished by coincubation with Leu(60)-IGF-I. If exogenous and secreted IGFBP-2 must bind to CCL64 cells to inhibit DNA synthesis, Leu(60)-IGF-I might reduce the inhibition of DNA synthesis by bIGFBP-2 or TGF-beta by inhibiting the association of IGFBP-2 in the media with CCL64 cells. Since TGF-beta does not increase IGFBP-2 abundance, we propose that TGF-beta sensitizes CCL64 cells to the latent growth inhibitory activity of endogenous IGFBP-2 by potentiating an intracellular IGFBP-2 signaling pathway or by promoting the association of secreted IGFBP-2 with the plasma membrane. PMID:11807812

  12. Transforming growth factor-β as a therapeutic target in hepatocellular carcinoma.

    PubMed

    Giannelli, Gianluigi; Villa, Erica; Lahn, Michael

    2014-04-01

    Hepatocellular carcinoma arises in patients as a consequence of long-standing preexisting liver illnesses, including viral hepatitis, alcohol abuse, or metabolic disease. In such preexisting liver diseases, TGF-β plays an important role in orchestrating a favorable microenvironment for tumor cell growth and promoting epithelial-mesenchymal transition (EMT). TGF-β signaling promotes hepatocellular carcinoma progression by two mechanisms: first, via an intrinsic activity as an autocrine or paracrine growth factor and, second, via an extrinsic activity by inducing microenvironment changes, including cancer-associated fibroblasts, T regulatory cells, and inflammatory mediators. Although there is an increasing understanding on how TGF-β signaling is associated with tumor progression in hepatocellular carcinoma, it is not clear whether TGF-β signaling is limited to a certain subgroup of patients with hepatocellular carcinoma or is a key driver of hepatocellular carcinoma during the entire tumorigenesis of hepatocellular carcinoma. Inhibitors of the TGF-β signaling have been shown to block hepatocellular carcinoma growth and progression by modulating EMT in different experimental models, leading to the clinical investigation of the TGF-β inhibitor LY2157299 monohydrate in hepatocellular carcinoma. Preliminary results from a phase II clinical trial have shown improved clinical outcome and also changes consistent with a reduction of EMT. PMID:24638984

  13. Antibacterial activity of sulfamethoxazole transformation products (TPs): general relevance for sulfonamide TPs modified at the para position.

    PubMed

    Majewsky, Marius; Wagner, Danny; Delay, Markus; Bräse, Stefan; Yargeau, Viviane; Horn, Harald

    2014-10-20

    Sulfonamide antibiotics undergo transformation in the aquatic environment through biodegradation, photolysis, or hydrolysis. In this study, the residual antibacterial activity of 11 transformation products (TPs) of sulfamethoxazole (SMX) was investigated with regard to their in vitro growth and luminescence inhibition on Vibrio fischeri (30 min and 24 h exposure). Two transformation products, 4-hydroxy-SMX and N(4)-hydroxy-acetyl-SMX, were synthesized in-house and confirmed by nuclear magnetic resonance and high-resolution mass spectrometry. Results of individual compound experiments showed that TPs modified at the para amino group still exhibit clear antibacterial effects, whereas TPs resulting from breakdown of the SMX structure lost this mechanism of action. 4-NO2- and 4-OH-SMX were found to inhibit growth to a clearly greater extent than the parent compound, SMX. In contrast, the N(4)-acetyl- and N(4)-hydroxy-acetyl-derivatives retain less than 10 and 5% of the effect of SMX on growth and luminescence inhibition, respectively. The effect of a mixture of para-modified TPs was observed to be additive. Considering the homologous series of sulfa drugs widely prescribed and their common mechanism of action, the potential environmental impact must consider the total amount of sulfonamide antibiotics and their derivative TPs, which might end up in a water body. Extrapolating the results obtained here for the para TPs of SMX to other sulfa drugs and determining the persistence and occurrence of these compounds in the aquatic environment is required for improved risk assessment. PMID:25211553

  14. Transforming growth factor-beta1 incorporated during setting in calcium phosphate cement stimulates bone cell differentiation in vitro.

    PubMed

    Blom, E J; Klein-Nulend, J; Klein, C P; Kurashina, K; van Waas, M A; Burger, E H

    2000-04-01

    Growth stimulation of periimplant tissues by growth factors like transforming growth factor-beta1 (TGF-beta1) may increase the indication for and success of implant use. Calcium phosphate as a material for implants or for coating of implants is known for its good biologic interaction with bone. Therefore, calcium phosphate implants combined with TGF-beta1 might improve osseointegration. In this study we hypothesise that the addition of recombinant human TGF-beta1 (rhTGF-beta1) to calcium phosphate cement (CPC) affects the differentiation of bone cells growing on the cement layer. rhTGF-beta1 incorporated during setting in a CPC layer at 20 ng rhTGF-beta1/60 mg cement was found to be gradually released into tissue culturing medium leading to a 20% release after 24 h. Two cell populations were obtained from collagenase-treated fragments of adult rat long bones: preosteoblastic cells, which were released by the collagenase treatment, and osteoblastic cells, which grew from the collagenase-stripped bone fragments. Both cell populations were tested for their osteoblastic characteristic phenotype by measuring their alkaline phosphatase (ALP) activity after vitamin D treatment and cyclic AMP after parathyroid hormone stimulation. After preculture the cells were plated on a layer of CPC containing 0 (control), 10, or 20 ng rhTGF-beta1/60 mg CPC. Bone cell differentiation was analyzed after 10 days by measuring the ALP activity, as well as the protein content of the cell layer. Incorporation of rhTGF-beta1 in the CPC did not change the ALP activity in osteoblastic cells, but a significant (analyzed by multivariate analysis of variance) increase was observed in preosteoblastic cells. Incorporation of 10 ng of rhTGF-beta1 in 60 mg of CPC increased the ALP activity in preosteoblastic cells by threefold and 20 ng rhTGF-beta1/60 mg CPC increased it by fivefold. The total protein content was not affected by rhTGF-beta1 in either of the cell populations. We conclude that rh

  15. The Interplay between Stem Cells, Microenvironment Mechanics, and Growth Factor activation

    PubMed Central

    Tenney, Rebeca M.; Discher, Dennis E.

    2009-01-01

    Physicochemical features of a cell’s microenvironment can exert important effects on cell behavior and include the effects of matrix elasticity on cell differentiation processes, but molecular mechanisms are largely mysterious. Here we highlight recent reports of a mechanical dependence to growth factor activation, with a particular focus on release of TGFβ (Transforming Growth Factor β) from its large latent complex via forced unfolding. We discuss these processes and pathways in the contexts of matrix adhesion and fluid shearing as they might relate to stem cell differentiation and other mechanisms in development, disease, and repair. PMID:19615877

  16. Activation loop phosphorylation regulates B-Raf in vivo and transformation by B-Raf mutants.

    PubMed

    Köhler, Martin; Röring, Michael; Schorch, Björn; Heilmann, Katharina; Stickel, Natalie; Fiala, Gina J; Schmitt, Lisa C; Braun, Sandra; Ehrenfeld, Sophia; Uhl, Franziska M; Kaltenbacher, Thorsten; Weinberg, Florian; Herzog, Sebastian; Zeiser, Robert; Schamel, Wolfgang W; Jumaa, Hassan; Brummer, Tilman

    2016-01-18

    Despite being mutated in cancer and RASopathies, the role of the activation segment (AS) has not been addressed for B-Raf signaling in vivo. Here, we generated a conditional knock-in mouse allowing the expression of the B-Raf(AVKA) mutant in which the AS phosphoacceptor sites T599 and S602 are replaced by alanine residues. Surprisingly, despite producing a kinase-impaired protein, the Braf(AVKA) allele does not phenocopy the lethality of Braf-knockout or paradoxically acting knock-in alleles. However, Braf(AVKA) mice display abnormalities in the hematopoietic system, a distinct facial morphology, reduced ERK pathway activity in the brain, and an abnormal gait. This phenotype suggests that maximum B-Raf activity is required for the proper development, function, and maintenance of certain cell populations. By establishing conditional murine embryonic fibroblast cultures, we further show that MEK/ERK phosphorylation and the immediate early gene response toward growth factors are impaired in the presence of B-Raf(AVKA). Importantly, alanine substitution of T599/S602 impairs the transformation potential of oncogenic non-V600E B-Raf mutants and a fusion protein, suggesting that blocking their phosphorylation could represent an alternative strategy to ATP-competitive inhibitors. PMID:26657898

  17. Radiation-Induced Liver Fibrosis Is Mitigated by Gene Therapy Inhibiting Transforming Growth Factor-{beta} Signaling in the Rat

    SciTech Connect

    Du Shisuo; Qiang Ming; Zeng Zhaochong; Zhou Jian; Tan Yunshan; Zhang Zhengyu; Zeng Haiying; Liu Zhongshan

    2010-12-01

    Purpose: We determined whether anti-transforming growth factor-{beta} (TGF-{beta}) intervention could halt the progression of established radiation-induced liver fibrosis (RILF). Methods and Materials: A replication-defective adenoviral vector expressing the extracellular portion of human T{beta}RII and the Fc portion of immunoglobulin G fusion protein (AdT{beta}RIIFc) was produced. The entire rat liver was exposed to 30 Gy irradiation to generate a RILF model (RILFM). Then, RILFM animals were treated with AdT{beta}RIIFc (1 x 10{sup 11} plaque-forming units [PFU] of T{beta}RII), control virus (1 x 10{sup 11} PFU of AdGFP), or saline. Delayed radiation liver injury was assessed by histology and immunohistochemistry. Chronic oxidative stress damage, hepatic stellate cell activation, and hepatocyte regeneration were also analyzed. Results: In rats infected with AdT{beta}RIIFc, fibrosis was significantly improved compared with rats treated with AdGFP or saline, as assessed by histology, hydroxyproline content, and serum level of hyaluronic acid. Compared with AdGFP rats, AdT{beta}RIIFc-treated rats exhibited decreased oxidative stress damage and hepatic stellate cell activation and preserved liver function. Conclusions: Our results demonstrate that TGF-{beta} plays a critical role in the progression of liver fibrosis and suggest that anti-TGF-{beta} intervention is feasible and ameliorates established liver fibrosis. In addition, chronic oxidative stress may be involved in the progression of RILF.

  18. Polyamine metabolism and transforming growth factor-beta signaling are affected in Caco-2 cells by differentially cooked broccoli extracts.

    PubMed

    Furniss, Caroline S M; Bennett, Richard N; Bacon, James R; LeGall, Gwen; Mithen, Richard F

    2008-10-01

    The health benefits of consuming cruciferous vegetables are widely considered to be due to the biological activity of glucosinolate degradation products. However, it is conceivable that other phytochemicals within crucifers may also have biological activity that may contribute to health benefits. In this study, we analyzed global gene expression in Caco-2 cells exposed to extracts derived from broccoli that had been heat treated to different extents to result in contrasting profiles of glucosinolates and their degradation products. Extracts microwaved for 0, 1, and 4 min contained 9.5, 25.5, and 0 micromol/L sulforaphane and induced changes in expression of 381, 1017, and 101 genes, respectively (>2 fold; P < 0.01). Seventy-two genes showed similar changes in expression after treatment with all 3 extracts. These included genes involved in polyamine catabolism and transforming growth factor (TGF)-beta signaling. Consistent with these changes in gene expression, subsequent studies demonstrated that exposing cells to these extracts, including the 4-min extract that contained no glucosinolate degradation products, increased putrescine and N-acetyl-spermine concentration, and suppressed the TGFbeta1-mediated induction of phosphorylated Smad 2. This is the first report, to our knowledge, of phytochemicals from a cruciferous vegetable affecting both a signaling pathway and a catabolic process. PMID:18806090

  19. Clinical development of galunisertib (LY2157299 monohydrate), a small molecule inhibitor of transforming growth factor-beta signaling pathway

    PubMed Central

    Herbertz, Stephan; Sawyer, J Scott; Stauber, Anja J; Gueorguieva, Ivelina; Driscoll, Kyla E; Estrem, Shawn T; Cleverly, Ann L; Desaiah, Durisala; Guba, Susan C; Benhadji, Karim A; Slapak, Christopher A; Lahn, Michael M

    2015-01-01

    Transforming growth factor-beta (TGF-β) signaling regulates a wide range of biological processes. TGF-β plays an important role in tumorigenesis and contributes to the hallmarks of cancer, including tumor proliferation, invasion and metastasis, inflammation, angiogenesis, and escape of immune surveillance. There are several pharmacological approaches to block TGF-β signaling, such as monoclonal antibodies, vaccines, antisense oligonucleotides, and small molecule inhibitors. Galunisertib (LY2157299 monohydrate) is an oral small molecule inhibitor of the TGF-β receptor I kinase that specifically downregulates the phosphorylation of SMAD2, abrogating activation of the canonical pathway. Furthermore, galunisertib has antitumor activity in tumor-bearing animal models such as breast, colon, lung cancers, and hepatocellular carcinoma. Continuous long-term exposure to galunisertib caused cardiac toxicities in animals requiring adoption of a pharmacokinetic/pharmacodynamic-based dosing strategy to allow further development. The use of such a pharmacokinetic/pharmacodynamic model defined a therapeutic window with an appropriate safety profile that enabled the clinical investigation of galunisertib. These efforts resulted in an intermittent dosing regimen (14 days on/14 days off, on a 28-day cycle) of galunisertib for all ongoing trials. Galunisertib is being investigated either as monotherapy or in combination with standard antitumor regimens (including nivolumab) in patients with cancer with high unmet medical needs such as glioblastoma, pancreatic cancer, and hepatocellular carcinoma. The present review summarizes the past and current experiences with different pharmacological treatments that enabled galunisertib to be investigated in patients. PMID:26309397

  20. Clinical development of galunisertib (LY2157299 monohydrate), a small molecule inhibitor of transforming growth factor-beta signaling pathway.

    PubMed

    Herbertz, Stephan; Sawyer, J Scott; Stauber, Anja J; Gueorguieva, Ivelina; Driscoll, Kyla E; Estrem, Shawn T; Cleverly, Ann L; Desaiah, Durisala; Guba, Susan C; Benhadji, Karim A; Slapak, Christopher A; Lahn, Michael M

    2015-01-01

    Transforming growth factor-beta (TGF-β) signaling regulates a wide range of biological processes. TGF-β plays an important role in tumorigenesis and contributes to the hallmarks of cancer, including tumor proliferation, invasion and metastasis, inflammation, angiogenesis, and escape of immune surveillance. There are several pharmacological approaches to block TGF-β signaling, such as monoclonal antibodies, vaccines, antisense oligonucleotides, and small molecule inhibitors. Galunisertib (LY2157299 monohydrate) is an oral small molecule inhibitor of the TGF-β receptor I kinase that specifically downregulates the phosphorylation of SMAD2, abrogating activation of the canonical pathway. Furthermore, galunisertib has antitumor activity in tumor-bearing animal models such as breast, colon, lung cancers, and hepatocellular carcinoma. Continuous long-term exposure to galunisertib caused cardiac toxicities in animals requiring adoption of a pharmacokinetic/pharmacodynamic-based dosing strategy to allow further development. The use of such a pharmacokinetic/pharmacodynamic model defined a therapeutic window with an appropriate safety profile that enabled the clinical investigation of galunisertib. These efforts resulted in an intermittent dosing regimen (14 days on/14 days off, on a 28-day cycle) of galunisertib for all ongoing trials. Galunisertib is being investigated either as monotherapy or in combination with standard antitumor regimens (including nivolumab) in patients with cancer with high unmet medical needs such as glioblastoma, pancreatic cancer, and hepatocellular carcinoma. The present review summarizes the past and current experiences with different pharmacological treatments that enabled galunisertib to be investigated in patients. PMID:26309397

  1. Histone deacetylase inhibitors and transforming growth factor-beta induce 15-hydroxyprostaglandin dehydrogenase expression in human lung adenocarcinoma cells.

    PubMed

    Tong, Min; Ding, Yunfei; Tai, Hsin-Hsiung

    2006-09-14

    Histone deacetylase (HDAC) inhibitors have been actively exploited as potential anticancer agents. To identify gene targets of HDAC inhibitors, we found that HDAC inhibitors such as sodium butyrate, scriptaid, apicidin and oxamflatin induced the expression of 15-hydroxyprostaglandin dehydrogenase (15-PGDH), a potential cyclooxygenase-2 (COX-2) antagonist and tumor suppressor, in a time and concentration dependent manner in A549 and H1435 lung adenocarcinoma cells. Detailed analyses indicated that HDAC inhibitors activated the 15-PGDH promoter-luciferase reporter construct in transfected A549 cells. A representative HDAC inhibitor, scriptaid, and its negative structural analog control, nullscript, were further evaluated at the chromatin level. Scriptaid but not nullscript induced a significant accumulation of acetylated histones H3 and H4 which were associated with the 15-PGDH promoter as determined by chromatin immunoprecipitation assay. Transforming growth factor-beta1 (TGF-beta1) also induced the expression of 15-PGDH in a time and concentration dependent manner in A549 and H1435 cells. Induction of 15-PGDH expression by TGF-beta1 was synergistically stimulated by the addition of Wnt3A which was inactive by itself. However, combination of TGF-beta and an HDAC inhibitor, scriptaid, only resulted in an additive effect. Together, our results indicate that 15-PGDH is one of the target genes that HDAC inhibitors and TGF-beta may induce to exhibit tumor suppressive effects. PMID:16844092

  2. Transforming growth factor. beta. sub 1 is present at sites of extracellular matrix gene expression in human pulmonary fibrosis

    SciTech Connect

    Broekelmann, T.J.; Limper, A.H.; McDonald, J.A. ); Colby, T.V. )

    1991-08-01

    Idiopathic pulmonary fibrosis is an inexorably fatal disorder characterized by connective tissue deposition within the terminal air spaces resulting in loss of lung function and eventual respiratory failure. Previously, the authors demonstrated that foci of activated fibroblasts expressing high levels of fibronectin, procollagen, and smooth muscle actin and thus resembling those found in healing wounds are responsible for the connective tissue deposition and scarring in idiopathic pulmonary fibrosis. Using in situ hybridization and immunohistochemistry, they now demonstrate the presence of transforming growth factor {beta}{sub 1} (TGF-{beta}{sub 1}), a potent profibrotic cytokine, in the foci containing these activated fibroblasts. These results suggest that matrix-associated TGF-{beta}{sub 1} may serve as a stimulus for the persistent expression of connective tissue genes. One potential source of the TGF-{beta}{sub 1} is the alveolar macrophage, and they demonstrate the expression of abundant TGF-{beta}{sub 1} mRNA in alveolar macrophages in lung tissue from patients with idiopathic pulmonary fibrosis.

  3. Transgenic mice overexpressing APP and transforming growth factor-beta1 feature cognitive and vascular hallmarks of Alzheimer's disease.

    PubMed

    Ongali, Brice; Nicolakakis, Nektaria; Lecrux, Clotilde; Aboulkassim, Tahar; Rosa-Neto, Pedro; Papadopoulos, Panayiota; Tong, Xin-Kang; Hamel, Edith

    2010-12-01

    High brain levels of amyloid-β (Aβ) and transforming growth factor-β1 (TGF-β1) have been implicated in the cognitive and cerebrovascular alterations of Alzheimer's disease (AD). We sought to investigate the impact of combined increases in Aβ and TGF-β1 on cerebrovascular, neuronal, and mnemonic function using transgenic mice overproducing these peptides (A/T mice). In particular, we measured cerebrovascular reactivity, evoked cerebral blood flow and glucose uptake during brain activation, cholinergic status, and spatial memory, along with cerebrovascular fibrosis, amyloidosis, and astrogliosis, and their evolution with age. An assessment of perfusion and metabolic responses was considered timely, given ongoing efforts for their validation as AD biomarkers. Relative to wild-type littermates, A/T mice displayed an early progressive decline in cerebrovascular dilatory ability, preserved contractility, and reduction in constitutive nitric oxide synthesis that establishes resting vessel tone. Altered levels of vasodilator-synthesizing enzymes and fibrotic proteins, resistance to antioxidant treatment, and unchanged levels of the antioxidant enzyme, superoxide dismutase-2, accompanied these impairments. A/T mice featured deficient neurovascular and neurometabolic coupling to whisker stimulation, cholinergic denervation, cerebral and cerebrovascular Aβ deposition, astrocyte activation, and impaired Morris water maze performance, which gained severity with age. The combined Aβ- and TGF-β1-driven pathology recapitulates salient cerebrovascular, neuronal, and cognitive AD landmarks and yields a versatile model toward highly anticipated diagnostic and therapeutic tools for patients featuring Aβ and TGF-β1 increments. PMID:21088218

  4. Astrocyte transforming growth factor beta 1 promotes inhibitory synapse formation via CaM kinase II signaling.

    PubMed

    Diniz, Luan Pereira; Tortelli, Vanessa; Garcia, Matheus Nunes; Araújo, Ana Paula Bérgamo; Melo, Helen M; Silva, Gisele S Seixas da; Felice, Fernanda G De; Alves-Leon, Soniza Vieira; Souza, Jorge Marcondes de; Romão, Luciana Ferreira; Castro, Newton Gonçalves; Gomes, Flávia Carvalho Alcantara

    2014-12-01

    The balance between excitatory and inhibitory synaptic inputs is critical for the control of brain function. Astrocytes play important role in the development and maintenance of neuronal circuitry. Whereas astrocytes-derived molecules involved in excitatory synapses are recognized, molecules and molecular mechanisms underlying astrocyte-induced inhibitory synapses remain unknown. Here, we identified transforming growth factor beta 1 (TGF-β1), derived from human and murine astrocytes, as regulator of inhibitory synapse in vitro and in vivo. Conditioned media derived from human and murine astrocytes induce inhibitory synapse formation in cerebral cortex neurons, an event inhibited by pharmacologic and genetic manipulation of the TGF-β pathway. TGF-β1-induction of inhibitory synapse depends on glutamatergic activity and activation of CaM kinase II, which thus induces localization and cluster formation of the synaptic adhesion protein, Neuroligin 2, in inhibitory postsynaptic terminals. Additionally, intraventricular injection of TGF-β1 enhanced inhibitory synapse number in the cerebral cortex. Our results identify TGF-β1/CaMKII pathway as a novel molecular mechanism underlying astrocyte control of inhibitory synapse formation. We propose here that the balance between excitatory and inhibitory inputs might be provided by astrocyte signals, at least partly achieved via TGF-β1 downstream pathways. Our work contributes to the understanding of the GABAergic synapse formation and may be of relevance to further the current knowledge on the mechanisms underlying the development of various neurological disorders, which commonly involve impairment of inhibitory synapse transmission. PMID:25042347

  5. Cell-autonomous cytokinin-independent growth of tobacco cells transformed by Agrobacterium tumefaciens strains lacking the cytokinin biosynthesis gene.

    PubMed Central

    Black, R C; Binns, A N; Chang, C F; Lynn, D G

    1994-01-01

    Mutations at the cytokinin biosynthesis locus (tmr) of Agrobacterium tumefaciens usually result in strains that induce tumors exhibiting the rooty phenotype associated with high auxin-to-cytokinin ratios. However, tobacco (Nicotiana tabacum cv Havana 425) leaf disc explants responded to tmr- mutant strain A356 by producing rapidly growing, unorganized tumors, indicating that these lines can grow in a cytokinin-independent fashion despite the absence of a functional tmr gene. Several methods have been used to characterize the physiological and cellular basis of this phenotype. The results indicate that tmr- tumors have a physiologically distinct mechanism for cytokinin-independent growth in comparison to tumors induced by wild-type bacteria. The cytokinin-independent phenotype of the tmr- transformants appears to be cell autonomous in nature: only the transformed cells and their progeny were capable of cytokinin-independent growth. Specifically, the tmr- tumors did not accumulate cytokinin, and clonal analysis indicated the tmr- transformed cells were not capable of stimulating the growth of neighboring nontransformed cells. Finally, the cytokinin-independent phenotype of the tmr- transformants was shown to be cold sensitive, whereas the wild-type tumors exhibited a cold-resistant cytokinin-independent phenotype. Potential mechanisms for this novel form of cytokinin-independent growth, including the role of the dehydrodiconiferyl alcohol glucosides found in both tumor types, are discussed. PMID:8058843

  6. From wavy hair to naked proteins: the role of transforming growth factor alpha in health and disease.

    PubMed

    Singh, Bhuminder; Coffey, Robert J

    2014-04-01

    Since its discovery in 1978 and cloning in 1984, transforming growth factor-alpha (TGF-α, TGFA) has been one of the most extensively studied EGF receptor (EGFR) ligands. In this review, we provide a historical perspective on TGFA-related studies, highlighting what we consider important advances related to its function in normal and disease states. PMID:24631356

  7. Increased susceptibility to atrial fibrillation secondary to atrial fibrosis in transgenic goats expressing transforming growth factor - B1

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia in people with significant morbidity and mortality. There is a strong association between atrial fibrosis and AF. Transforming growth factor B1 (TGF-B1) is an essential mediator of atrial fibrosis in animal models and human pat...

  8. Long Non-coding RNAs (LncRNA) Regulated by Transforming Growth Factor (TGF) β

    PubMed Central

    Richards, Edward J.; Zhang, Gu; Li, Zhu-Peng; Permuth-Wey, Jennifer; Challa, Sridevi; Li, Yajuan; Kong, William; Dan, Su; Bui, Marilyn M.; Coppola, Domenico; Mao, Wei-Min; Sellers, Thomas A.; Cheng, Jin Q.

    2015-01-01

    Long noncoding RNAs (lncRNAs) are emerging as key regulators in various biological processes. Epithelial-to-mesenchymal transition (EMT) is a developmental process hijacked by tumor cells to depart from the primary tumor site, invade surrounding tissue, and establish distant metastases. Transforming growth factor β (TGFβ) signaling has been shown to be a major inducer of EMT and to facilitate breast cancer metastasis. However, the role of lncRNAs in this process remains largely unknown. Here we report a genome-wide lncRNA profile in mouse mammary epithelial NMuMG cells upon TGFβ induction of EMT. Among 10,802 lncRNAs profiled, over 600 were up-regulated and down-regulated during the EMT, respectively. Furthermore, we identify that lncRNA-HIT (HOXA transcript induced by TGFβ) mediates TGFβ function, i.e. depletion of lncRNA-HIT inhibits TGFβ-induced migration, invasion, and EMT in NMuMG. LncRNA-HIT is also significantly elevated in the highly metastatic 4T1 cells. Knockdown of lncRNA-HIT in 4T1 results in decrease of cell migration, invasion, tumor growth, and metastasis. E-cadherin was identified as a major target of lncRNA-HIT. Moreover, lncRNA-HIT is conserved in humans and elevated expression associates with more invasive human primary breast carcinoma. Collectively, these data suggest that a subset of lncRNAs such as lncRNA-HIT play a significant role in regulation of EMT and breast cancer invasion and metastasis, and could be potential therapeutic targets in breast cancers. PMID:25605728

  9. Hypertrophic stimuli induce transforming growth factor-beta 1 expression in rat ventricular myocytes.

    PubMed Central

    Takahashi, N; Calderone, A; Izzo, N J; Mäki, T M; Marsh, J D; Colucci, W S

    1994-01-01

    Transforming growth factor-beta 1 (TGF-beta 1) is a peptide growth factor that may play a role in the myocardial response to hypertrophic stimuli. However, the cellular distribution, mechanism of induction, and source of increased TGF-beta 1 in response to hypertrophic stimuli are not known. We tested the hypothesis that the cardiac myocyte responds to hypertrophic stimuli with the increased expression of TGF-beta 1. In adult rat ventricular myocardium freshly dissociated into myocyte and nonmyocyte cellular fractions, the preponderance of TGF-beta 1 mRNA visualized by Northern hybridization was in the nonmyocyte fraction. Abdominal aortic constriction (7 d) and subcutaneous norepinephrine infusion (36 h) each caused ventricular hypertrophy associated with 3.1-fold and 3.8-fold increases, respectively, in TGF-beta 1 mRNA in the myocyte fraction, but had no effect on the level of TGF-beta 1 mRNA in the nonmyocyte fraction. In ventricular myocytes, norepinephrine likewise caused a 4.1-fold increase in TGF-beta 1 mRNA associated with an increase in TGF-beta bioactivity. This induction of TGF-beta 1 mRNA occurred at norepinephrine concentrations as low as 1 nM and was blocked by prazosin, but not propranolol. NE did not increase the TGF-beta 1 mRNA level in nonmyocytes, primarily fibroblasts, cultured from neonatal rat ventricle. Thus, the cardiac myocyte responds to two hypertrophic stimuli, pressure overload and norepinephrine, with the induction of TGF-beta 1. These data support the view that TGF-beta 1, released by myocytes and acting in an autocrine and/or paracrine manner, is involved in myocardial remodeling by hypertrophic stimuli. Images PMID:7929822

  10. Transforming growth factor: beta signaling is essential for limb regeneration in axolotls.

    PubMed

    Lévesque, Mathieu; Gatien, Samuel; Finnson, Kenneth; Desmeules, Sophie; Villiard, Eric; Pilote, Mireille; Philip, Anie; Roy, Stéphane

    2007-01-01

    Axolotls (urodele amphibians) have the unique ability, among vertebrates, to perfectly regenerate many parts of their body including limbs, tail, jaw and spinal cord following injury or amputation. The axolotl limb is the most widely used structure as an experimental model to study tissue regeneration. The process is well characterized, requiring multiple cellular and molecular mechanisms. The preparation phase represents the first part of the regeneration process which includes wound healing, cellular migration, dedifferentiation and proliferation. The redevelopment phase represents the second part when dedifferentiated cells stop proliferating and redifferentiate to give rise to all missing structures. In the axolotl, when a limb is amputated, the missing or wounded part is regenerated perfectly without scar formation between the stump and the regenerated structure. Multiple authors have recently highlighted the similarities between the early phases of mammalian wound healing and urodele limb regeneration. In mammals, one very important family of growth factors implicated in the control of almost all aspects of wound healing is the transforming growth factor-beta family (TGF-beta). In the present study, the full length sequence of the axolotl TGF-beta1 cDNA was isolated. The spatio-temporal expression pattern of TGF-beta1 in regenerating limbs shows that this gene is up-regulated during the preparation phase of regeneration. Our results also demonstrate the presence of multiple components of the TGF-beta signaling machinery in axolotl cells. By using a specific pharmacological inhibitor of TGF-beta type I receptor, SB-431542, we show that TGF-beta signaling is required for axolotl limb regeneration. Treatment of regenerating limbs with SB-431542 reveals that cellular proliferation during limb regeneration as well as the expression of genes directly dependent on TGF-beta signaling are down-regulated. These data directly implicate TGF-beta signaling in the

  11. Transforming Growth Factor: β Signaling Is Essential for Limb Regeneration in Axolotls

    PubMed Central

    Lévesque, Mathieu; Gatien, Samuel; Finnson, Kenneth; Desmeules, Sophie; Villiard, Éric; Pilote, Mireille; Philip, Anie; Roy, Stéphane

    2007-01-01

    Axolotls (urodele amphibians) have the unique ability, among vertebrates, to perfectly regenerate many parts of their body including limbs, tail, jaw and spinal cord following injury or amputation. The axolotl limb is the most widely used structure as an experimental model to study tissue regeneration. The process is well characterized, requiring multiple cellular and molecular mechanisms. The preparation phase represents the first part of the regeneration process which includes wound healing, cellular migration, dedifferentiation and proliferation. The redevelopment phase represents the second part when dedifferentiated cells stop proliferating and redifferentiate to give rise to all missing structures. In the axolotl, when a limb is amputated, the missing or wounded part is regenerated perfectly without scar formation between the stump and the regenerated structure. Multiple authors have recently highlighted the similarities between the early phases of mammalian wound healing and urodele limb regeneration. In mammals, one very important family of growth factors implicated in the control of almost all aspects of wound healing is the transforming growth factor-beta family (TGF-β). In the present study, the full length sequence of the axolotl TGF-β1 cDNA was isolated. The spatio-temporal expression pattern of TGF-β1 in regenerating limbs shows that this gene is up-regulated during the preparation phase of regeneration. Our results also demonstrate the presence of multiple components of the TGF-β signaling machinery in axolotl cells. By using a specific pharmacological inhibitor of TGF-β type I receptor, SB-431542, we show that TGF-β signaling is required for axolotl limb regeneration. Treatment of regenerating limbs with SB-431542 reveals that cellular proliferation during limb regeneration as well as the expression of genes directly dependent on TGF-β signaling are down-regulated. These data directly implicate TGF-β signaling in the initiation and control

  12. Hair Growth Promotion Activity and Its Mechanism of Polygonum multiflorum

    PubMed Central

    Li, Yunfei; Han, Mingnuan; Lin, Pei; He, Yanran; Yu, Jie; Zhao, Ronghua

    2015-01-01

    Polygonum multiflorum Radix (PMR) has long history in hair growth promotion and hair coloring in clinical applications. However, several crucial problems in its clinic usage and mechanisms are still unsolved or lack scientific evidences. In this research, C57BL/6J mice were used to investigate hair growth promotion activity and possible mechanism of PMR and Polygonum multiflorum Radix Preparata (PMRP). Hair growth promotion activities were investigated by hair length, hair covered skin ratio, the number of follicles, and hair color. Regulation effects of several cytokines involved in the hair growth procedure were tested, such as fibroblast growth factor (FGF-7), Sonic Hedgehog (SHH), β-catenin, insulin-like growth factor-1 (IGF-1), and hepatocyte growth factor (HGF). Oral PMR groups had higher hair covered skin ratio (100 ± 0.00%) than oral PMRP groups (48%~88%). However, topical usage of PMRP had about 90% hair covered skin ratio. Both oral administration of PMR and topically given PMRP showed hair growth promotion activities. PMR was considered to be more suitable for oral administration, while PMRP showed greater effects in external use. The hair growth promotion effect of oral PMR was most probably mediated by the expression of FGF-7, while topical PMRP promoted hair growth by the stimulation of SHH expression. PMID:26294926

  13. uPAR Induces Expression of Transforming Growth Factor β and Interleukin-4 in Cancer Cells to Promote Tumor-Permissive Conditioning of Macrophages

    PubMed Central

    Hu, Jingjing; Jo, Minji; Eastman, Boryana M.; Gilder, Andrew S.; Bui, Jack D.; Gonias, Steven L.

    2015-01-01

    Cancer cells condition macrophages and other inflammatory cells in the tumor microenvironment so that these cells are more permissive for cancer growth and metastasis. Conditioning of inflammatory cells reflects, at least in part, soluble mediators (such as transforming growth factor β and IL-4) that are released by cancer cells and alter the phenotype of cells of the innate immune system. Signaling pathways in cancer cells that potentiate this activity are incompletely understood. The urokinase receptor (uPAR) is a cell-signaling receptor known to promote cancer cell survival, proliferation, metastasis, and cancer stem cell–like properties. The present findings show that uPAR expression in diverse cancer cells, including breast cancer, pancreatic cancer, and glioblastoma cells, promotes the ability of these cells to condition co-cultured bone marrow–derived macrophages so that the macrophages express significantly increased levels of arginase 1, a biomarker of the alternatively activated M2 macrophage phenotype. Expression of transforming growth factor β was substantially increased in uPAR-expressing cancer cells via a mechanism that requires uPA-initiated cell signaling. uPAR also controlled expression of IL-4 in cancer cells via a mechanism that involves activation of ERK1/2. The ability of uPAR to induce expression of factors that condition macrophages in the tumor microenvironment may constitute an important mechanism by which uPAR promotes cancer progression. PMID:25310970

  14. Using the Learning Activities Survey to Examine Transformative Learning Experiences in Two Graduate Teacher Preparation Courses

    ERIC Educational Resources Information Center

    Caruana, Vicki; Woodrow, Kelli; Pérez, Luis

    2015-01-01

    The Learning Activities Survey (LAS) detected whether, and to what extent, a perspective transformation occurred during two graduate courses in teacher preparation. The LAS examined the types of learning identified as contributing to their transformative experiences. This study examined pre-service teachers' critical reflection of the course…

  15. American Student Activism: The Post-Sixties Transformation.

    ERIC Educational Resources Information Center

    Altbach, Philip G.; Cohen, Robert

    1990-01-01

    The trends in college student attitudes and activism in the 1980s are explored, focusing on patterns of attitudes, issues that motivate students, and the campuses on which activism appears to flourish. (MSE)

  16. Protective effect of transforming growth factor beta 1 on experimental autoimmune diseases in mice.

    PubMed

    Kuruvilla, A P; Shah, R; Hochwald, G M; Liggitt, H D; Palladino, M A; Thorbecke, G J

    1991-04-01

    Interleukin 1 (IL-1) and tumor necrosis factor alpha are thought to contribute to the inflammatory response associated with autoimmune diseases. Transforming growth factor beta 1 (TGF-beta 1) counteracts many effects of these cytokines and has various immunosuppressive properties. In the present study, it is shown that microgram amounts of TGF-beta 1, injected daily for 1-2 weeks, protect against collagen-induced arthritis (CIA) and relapsing experimental allergic encephalomyelitis (REAE), the animal models for rheumatoid arthritis and multiple sclerosis, respectively. When administered during induction of the disease, TGF-beta 1 prevents CIA but only delays the onset of REAE by 2-3 days. However, when administered during a remission. TGF-beta 1 prevents the occurrence of relapses in REAE. The results suggest that TGF-beta 1 has powerful anti-inflammatory effects, mimicking in some respects the beneficial effects of immunosuppressive drugs in these experimental models of autoimmune disease, but without discernable adverse effects. PMID:2011600

  17. Loss of transforming growth factor-beta 2 leads to impairment of central synapse function

    PubMed Central

    Heupel, Katharina; Sargsyan, Vardanush; Plomp, Jaap J; Rickmann, Michael; Varoqueaux, Frédérique; Zhang, Weiqi; Krieglstein, Kerstin

    2008-01-01

    Background The formation of functional synapses is a crucial event in neuronal network formation, and with regard to regulation of breathing it is essential for life. Members of the transforming growth factor-beta (TGF-β) superfamily act as intercellular signaling molecules during synaptogenesis of the neuromuscular junction of Drosophila and are involved in synaptic function of sensory neurons of Aplysia. Results Here we show that while TGF-β2 is not crucial for the morphology and function of the neuromuscular junction of the diaphragm muscle of mice, it is essential for proper synaptic function in the pre-Bötzinger complex, a central rhythm organizer located in the brainstem. Genetic deletion of TGF-β2 in mice strongly impaired both GABA/glycinergic and glutamatergic synaptic transmission in the pre-Bötzinger complex area, while numbers and morphology of central synapses of knock-out animals were indistinguishable from their wild-type littermates at embryonic day 18.5. Conclusion The results demonstrate that TGF-β2 influences synaptic function, rather than synaptogenesis, specifically at central synapses. The functional alterations in the respiratory center of the brain are probably the underlying cause of the perinatal death of the TGF-β2 knock-out mice. PMID:18854036

  18. Association of interleukin 10 and transforming growth factor β gene polymorphisms with chronic idiopathic urticaria.

    PubMed

    Tavakol, Marzieh; Movahedi, Masoud; Amirzargar, Ali Akbar; Aryan, Zahra; Bidoki, Alireza Zare; Heidari, Kimia; Soltani, Samaneh; Gharagozlou, Mohammad; Aghamohammadi, Asghar; Nabavi, Mohammad; Nasiri, Rasoul; Ahmadvand, Alireza; Rezaei, Nima

    2014-01-01

    Transforming growth factor β (TGF-β) and interleukin 10 (IL-10) are two anti-inflammatory cytokines that are implicated in the pathogenesis of urticaria. The goal of this study was to examine the possible association of polymorphisms of TGF-β and IL-10 genes with susceptibility to chronic idiopathic urticaria (CIU). This study was conducted on 90 patients with CIU. Polymerase chain reaction (PCR) was done to determine the genotype at 5 polymorphic sites; TGF-β (codon10C/T and codon25G/C) and IL-10 (-1082G/A, -819C/T, and -592C/A). The C allele at codon 25 of TGF-β was more prevalent in CIU patients compared to controls (OR = 9.5, 95% CI = 5.4-16.8, P<0.001). Genotypes of CT and CG at 10 and 25 codons of TGF-β gene, respectively, and AG, CT, and CA for loci of -1082, -819, and -592 of IL-10 gene were significantly higher in CIU patients (P<0.001). In haplotype analysis, frequency of TGF-β haplotypes differed between patients with CIU and controls; CC haplotype was overrepresented, while CG and TG haplotypes were underrepresented (P<0.001). These results suggest that TGF-β and IL-10 genetic variability could contribute to susceptibility to CIU. Additionally, patients with CIU seem to have genotypes leading to high production of TGF-β and IL-10. PMID:25580782

  19. Mitotic Asynchrony Induces Transforming Growth Factor-β1 Secretion from Airway Epithelium

    PubMed Central

    Alcala, Sarah E.; Benton, Angela S.; Watson, Alan M.; Kureshi, Suraiya; Reeves, Erica M. K.; Damsker, Jesse; Wang, Zuyi; Nagaraju, Kanneboyina; Anderson, Julia; Williams, Aaron M.; Lee, Amber J. Y.; Hayes, Kathleen; Rose, Mary C.; Hoffman, Eric P.

    2014-01-01

    We recently proposed that mitotic asynchrony in repairing tissue may underlie chronic inflammation and fibrosis, where immune cell infiltration is secondary to proinflammatory cross-talk among asynchronously repairing adjacent tissues. Building on our previous finding that mitotic asynchrony is associated with proinflammatory/fibrotic cytokine secretion (e.g., transforming growth factor [TGF]-β1), here we provide evidence supporting cause-and-effect. Under normal conditions, primary airway epithelial basal cell populations undergo mitosis synchronously and do not secrete proinflammatory or profibrotic cytokines. However, when pairs of nonasthmatic cultures were mitotically synchronized at 12 hours off-set and then combined, the mixed cell populations secreted elevated levels of TGF-β1. This shows that mitotic asynchrony is not only associated with but is also causative of TGF-β1 secretion. The secreted cytokines and other mediators from asthmatic cells were not the cause of asynchronous regeneration; synchronously mitotic nonasthmatic epithelia exposed to conditioned media from asthmatic cells did not show changes in mitotic synchrony. We also tested if resynchronization of regenerating asthmatic airway epithelia reduces TGF-β1 secretion and found that pulse-dosed dexamethasone, simvastatin, and aphidicolin were all effective. We therefore propose a new model for chronic inflammatory and fibrotic conditions where an underlying factor is mitotic asynchrony. PMID:24669775

  20. Transforming growth factor-β1 in carcinogenesis, progression, and therapy in cervical cancer.

    PubMed

    Zhu, Haiyan; Luo, Hui; Shen, Zhaojun; Hu, Xiaoli; Sun, Luzhe; Zhu, Xueqiong

    2016-06-01

    Transforming growth factor β1 (TGF-β1) is a multifunctional cytokine that plays important roles in cervical tumor formation, invasion, progression, and metastasis. TGF-β1 functions as a tumor inhibitor in precancerous lesions and early stage cancers of cervix whereas as a tumor promoter in later stage. This switch from a tumor inhibitor to a tumor promoter might be due to various alterations in TGF-β signaling pathway, such as mutations or loss of expression of TGF-β receptors and SMAD proteins. Additionally, the oncoproteins of human papillomaviruses have been shown to stimulate TGF-β1 expression, which in turn suppresses host immune surveillance. Thus, in addition to driving tumor cell migration and metastasis, TGF-β1 is believed to play a key role in promoting human papillomavirus infection by weakening host immune defense. In this article, we will discuss the role of TGF-β1 in the expression, carcinogenesis, progression, and therapy in cervical cancers. A better understanding of this cytokine in cervical carcinogenesis is essential for critical evaluation of this cytokine as a potential prognostic marker and therapeutic target. PMID:27010470

  1. Metformin is a novel suppressor for transforming growth factor (TGF)-β1.

    PubMed

    Xiao, Han; Zhang, Jianshu; Xu, Zhonghe; Feng, Yenan; Zhang, Mingliang; Liu, Jianli; Chen, Ruifei; Shen, Jing; Wu, Jimin; Lu, Zhizhen; Fang, Xiaohong; Li, Jingyuan; Zhang, Youyi

    2016-01-01

    Metformin is a widely used first-line antidiabetic drug that has been shown to protect against a variety of specific diseases in addition to diabetes, including cardiovascular disorders, polycystic ovary syndrome, and cancer. However, the precise mechanisms underlying the diverse therapeutic effects of metformin remain elusive. Here, we report that transforming growth factor-β1 (TGF-β1), which is involved in the pathogenesis of numerous diseases, is a novel target of metformin. Using a surface plasmon resonance-based assay, we identified the direct binding of metformin to TGF-β1 and found that metformin inhibits [(125)I]-TGF-β1 binding to its receptor. Furthermore, based on molecular docking and molecular dynamics simulations, metformin was predicted to interact with TGF-β1 at its receptor-binding domain. Single-molecule force spectroscopy revealed that metformin reduces the binding probability but not the binding force of TGF-β1 to its type II receptor. Consequently, metformin suppresses type II TGF-β1 receptor dimerization upon exposure to TGF-β1, which is essential for downstream signal transduction. Thus, our results indicate that metformin is a novel TGF-β suppressor with therapeutic potential for numerous diseases in which TGF-β1 hyperfunction is indicated. PMID:27349853

  2. Uptake of Host Cell Transforming Growth Factor-β by Trypanosoma cruzi Amastigotes in Cardiomyocytes

    PubMed Central

    Waghabi, Mariana C.; Keramidas, Michelle; Bailly, Sabine; Degrave, Wim; Mendonça-Lima, Leila; Soeiro, Maria de Nazaré C.; Meirelles, Maria de Nazareth L.; Paciornik, Sidnei; Araújo-Jorge, Tania C.; Feige, Jean-Jacques

    2005-01-01

    The cytokine transforming growth factor-β (TGF-β) plays various functions in the control of Trypanosoma cruzi infectivity and in the progression of Chagas’ disease. When we immunostained T. cruzi-infected cardiomyocytes (after either in vivo or in vitro infections) for TGF-β, we observed stronger immunoreactivity in parasites than in host cells. TGF-β immunoreactivity evolved during parasite cycle progression, with intense staining in amastigotes versus very faint staining in trypomastigotes. TGF-β was present on the surface of amastigotes, in the flagellar pocket, and in intraparasitic vesicles as revealed by electron microscopy. However, no ortholog TGF-β gene could be identified in the genome of T. cruzi by in silico analysis or by extensive polymerase chain reaction and reverse transcriptase-polymerase chain reaction studies. Immunoreactive TGF-β was most probably taken up by the parasite from the host cell cytoplasm because such an internalization process of biotinylated TGF-β could be observed in axenic amastigotes in vitro. These observations represent the first example of a novel mechanism by which a primitive unicellular protozoan can use host cell TGF-β to control its own intracellular life cycle. PMID:16192635

  3. Transforming growth factor β1 inhibition protects from noise-induced hearing loss

    PubMed Central

    Murillo-Cuesta, Silvia; Rodríguez-de la Rosa, Lourdes; Contreras, Julio; Celaya, Adelaida M.; Camarero, Guadalupe; Rivera, Teresa; Varela-Nieto, Isabel

    2015-01-01

    Excessive exposure to noise damages the principal cochlear structures leading to hearing impairment. Inflammatory and immune responses are central mechanisms in cochlear defensive response to noise but, if unregulated, they contribute to inner ear damage and hearing loss. Transforming growth factor β (TGF-β) is a key regulator of both responses and high levels of this factor have been associated with cochlear injury in hearing loss animal models. To evaluate the potential of targeting TGF-β as a therapeutic strategy for preventing or ameliorating noise-induced hearing loss (NIHL), we studied the auditory function, cochlear morphology, gene expression and oxidative stress markers in mice exposed to noise and treated with TGF-β1 peptidic inhibitors P17 and P144, just before or immediately after noise insult. Our results indicate that systemic administration of both peptides significantly improved both the evolution of hearing thresholds and the degenerative changes induced by noise-exposure in lateral wall structures. Moreover, treatments ameliorated the inflammatory state and redox balance. These therapeutic effects were dose-dependent and more effective if the TGF-β1 inhibitors were administered prior to inducing the injury. In conclusion, inhibition of TGF-β1 actions with antagonistic peptides represents a new, promising therapeutic strategy for the prevention and repair of noise-induced cochlear damage. PMID:25852546

  4. Transforming Growth Factor-β Signaling Guides the Differentiation of Innate Lymphoid Cells in Salivary Glands.

    PubMed

    Cortez, Victor S; Cervantes-Barragan, Luisa; Robinette, Michelle L; Bando, Jennifer K; Wang, Yaming; Geiger, Theresa L; Gilfillan, Susan; Fuchs, Anja; Vivier, Eric; Sun, Joe C; Cella, Marina; Colonna, Marco

    2016-05-17

    The signals guiding differentiation of innate lymphoid cells (ILCs) within tissues are not well understood. Salivary gland (SG) ILCs as well as liver and intestinal intraepithelial ILC1 have markers that denote tissue residency and transforming growth factor-β (TGF-β) imprinting. We deleted Tgfbr2 in cells expressing the ILC and NK marker NKp46 and found that SG ILCs were reduced in number. They lost distinct tissue markers, such as CD49a, and the effector molecules TRAIL and CD73. Expression of the transcription factor Eomes, which promotes NK cell differentiation, was elevated. Conversely, Eomes deletion in NKp46(+) cells enhanced TGF-β-imprinting of SG ILCs. Thus, TGF-β induces SG ILC differentiation by suppressing Eomes. TGF-β acted through a JNK-dependent, Smad4-independent pathway. Transcriptome analysis demonstrated that SG ILCs had characteristic of both NK cells and ILC1. Finally, TGF-β imprinting of SG ILCs was synchronized with SG development, highlighting the impact of tissue microenvironment on ILC development. PMID:27156386

  5. Transforming growth factor β1 inhibition protects from noise-induced hearing loss.

    PubMed

    Murillo-Cuesta, Silvia; Rodríguez-de la Rosa, Lourdes; Contreras, Julio; Celaya, Adelaida M; Camarero, Guadalupe; Rivera, Teresa; Varela-Nieto, Isabel

    2015-01-01

    Excessive exposure to noise damages the principal cochlear structures leading to hearing impairment. Inflammatory and immune responses are central mechanisms in cochlear defensive response to noise but, if unregulated, they contribute to inner ear damage and hearing loss. Transforming growth factor β (TGF-β) is a key regulator of both responses and high levels of this factor have been associated with cochlear injury in hearing loss animal models. To evaluate the potential of targeting TGF-β as a therapeutic strategy for preventing or ameliorating noise-induced hearing loss (NIHL), we studied the auditory function, cochlear morphology, gene expression and oxidative stress markers in mice exposed to noise and treated with TGF-β1 peptidic inhibitors P17 and P144, just before or immediately after noise insult. Our results indicate that systemic administration of both peptides significantly improved both the evolution of hearing thresholds and the degenerative changes induced by noise-exposure in lateral wall structures. Moreover, treatments ameliorated the inflammatory state and redox balance. These therapeutic effects were dose-dependent and more effective if the TGF-β1 inhibitors were administered prior to inducing the injury. In conclusion, inhibition of TGF-β1 actions with antagonistic peptides represents a new, promising therapeutic strategy for the prevention and repair of noise-induced cochlear damage. PMID:25852546

  6. E1A inhibits transforming growth factor-beta signaling through binding to Smad proteins.

    PubMed

    Nishihara, A; Hanai, J; Imamura, T; Miyazono, K; Kawabata, M

    1999-10-01

    Smads form a recently identified family of proteins that mediate intracellular signaling of the transforming growth factor (TGF)-beta superfamily. Smads bind to DNA and act as transcriptional regulators. Smads interact with a variety of transcription factors, and the interaction is likely to determine the target specificity of gene induction. Smads also associate with transcriptional coactivators such as p300 and CBP. E1A, an adenoviral oncoprotein, inhibits TGF-beta-induced transactivation, and the ability of E1A to bind p300/CBP is required for the inhibition. Here we determined the Smad interaction domain (SID) in p300 and found that two adjacent regions are required for the interaction. One of the regions is the C/H3 domain conserved between p300 and CBP, and the other is a nonconserved region. p300 mutants containing SID inhibit transactivation by TGF-beta in a dose-dependent manner. E1A inhibits the interaction of Smad3 with a p300 mutant that contains SID but lacks the E1A binding domain. We found that E1A interacts specifically with receptor-regulated Smads, suggesting a novel mechanism whereby E1A antagonizes TGF-beta signaling. PMID:10497242

  7. Roles of transforming growth factor β in hyperoxia-induced lung injury.

    PubMed

    Liu, Y; Mao, Y F; Zheng, J; Liu, K; Han, C H; Liu, W W

    2016-01-01

    Hyperoxia induced lung injury (HILI) refers to the acute lung injury secondary to prolonged exposure to hyperoxia at elevated partial pressure. With the advent of efficient systems for delivery of high concentrations of oxygen in hospitals, the population at risk for this condition has been markedly increased. Although numerous studies have been conducted to investigate the pathogenesis of HILI, the specific mechanism is still poorly understood and some hypotheses have been proposed. Transforming growth factor β (TGF-β) is a secreted protein that controls proliferation, cellular differentiation and other functions in most cells and is a type of cytokine that plays a role in many diseases. In this mini-review, we summarize the role of TGF-β in HILI according to its relationships with reactive oxygen species (ROS), pro-inflammatory cytokines, cell apoptosis and pulmonary fibrosis. We hope it may help the understanding of pathogenesis of HILI and provide a greater understanding for the target therapy of HILI. PMID:27416690

  8. Effect of transforming growth factor-β3 on mono and multilayer chondrocytes.

    PubMed

    Sefat, Farshid; Youseffi, Mansour; Khaghani, Seyed Ali; Soon, Chin Fhung; Javid, Farideh

    2016-07-01

    Articular cartilage is an avascular and flexible connective tissue found in joints. It produces a cushioning effect at the joints and provides low friction to protect the ends of the bones from wear and tear/damage. It has poor repair capacity and any injury can result pain and loss of mobility. Transforming growth factor-beta (TGF-β), a cytokine superfamily, regulates cell function, including differentiation and proliferation. Although the function of the TGF-βs in various cell types has been investigated, their function in cartilage repair is as yet not fully understood. The effect of TGF-β3 in biological regulation of primary chondrocyte was investigated in this work. TGF-β3 provided fibroblastic morphology to chondrocytes and therefore overall reduction in cell proliferation was observed. The length of the cells supplemented with TGF-β3 were larger than the cells without TGF-β3 treatment. This was caused by the fibroblast like cells (dedifferentiated chondrocytes) which occupied larger areas compared to cells without TGF-β3 addition. The healing process of the model wound closure assay of chondrocyte multilayer was slowed down by TGF-β3, and this cytokine negatively affected the strength of chondrocyte adhesion to the cell culture surface. PMID:27108397

  9. Elevated Transforming Growth Factor β1 in Plasma of Primary Open-Angle Glaucoma Patients

    PubMed Central

    Kuchtey, John; Kunkel, Jessica; Burgess, L. Goodwin; Parks, Megan B.; Brantley, Milam A.; Kuchtey, Rachel W.

    2014-01-01

    Purpose. To test the hypothesis that primary open-angle glaucoma (POAG) patients have a systemic elevation of transforming growth factor β1 (TGFβ1). Methods. Plasma was prepared from blood samples drawn from patients of the Vanderbilt Eye Institute during clinic visits. Concentrations of total TGFβ1 and thrombospondin-1 (TSP1) in plasma were determined by ELISA. Statistical significance of differences between POAG and control samples was evaluated by Mann-Whitney test. Regression analysis was used to evaluate correlations between plasma TGFβ1 and patient age and between plasma TGFβ1 and TSP1. Results. Plasma samples were obtained from 148 POAG patients and 150 controls. Concentration of total TGFβ1 in the plasma of POAG patients (median = 3.25 ng/mL) was significantly higher (P < 0.0001) than in controls (median = 2.46 ng/mL). Plasma TGFβ1 was not correlated with age of patient (P = 0.17). Thrombospondin-1 concentration was also significantly higher (P < 0.0001) in POAG patients (median = 0.774 μg/mL) as compared to controls (median = 0.567 μg/mL). Plasma total TGFβ1 and TSP1 concentrations were linearly correlated (P < 0.0001). Conclusions. Plasma samples from POAG patients display elevated total TGFβ1 compared to controls, consistent with elevated systemic TGFβ1 in POAG patients. PMID:25061114

  10. Transforming growth factor beta (TGF-β) isomers influence cell detachment of MG-63 bone cells.

    PubMed

    Sefat, Farshid; Khaghani, Seyed Ali; Nejatian, Touraj; Genedy, Mohammed; Abdeldayem, Ali; Moghaddam, Zoha Salehi; Denyer, Morgan C T; Youseffi, Mansour

    2015-12-01

    Bone repair and wound healing are modulated by different stimuli. There is evidence that Transforming Growth Factor-beta (TGF-β) super-family of cytokines have significant effects on bone structure by regulating the replication and differentiation of chondrocytes, osteoblasts and osteoclasts. There is also significant evidence that interactions with extracellular matrix molecules influence cell behaviour. In this study cell surface attachment was examined via a trypsinization assay using various TGF-β isomers in which the time taken to trypsinize cells from the surface provided a means of assessing the strength of attachment. Three TGF-β isomers (TGF-β1, 2 and 3), four combined forms (TGF-β(1+2), TGF-β(1+3), TGF-β(2+3) and TGF-β(1+2+3)) along with four different controls (BSA, HCl, BSA/HCl and negative control) were investigated in this study. The results indicated that treatment with TGF-β1, 2, 3 and HCl decreased cell attachment, however, this effect was significantly greater in the case of TGF-β3 (p<0.001) indicating perhaps that TGF-β3 does not act alone in cell detachment, but instead functions synergistically with signalling pathways that are dependent on the availability of hydrogen ions. Widefield Surface Plasmon Resonance (WSPR) microscope was also used to investigate cell surface interactions. PMID:26372305

  11. Effects of transforming growth factor beta 1 on the regulation of osteoclastic development and function

    SciTech Connect

    Hattersley, G.; Chambers, T.J. )

    1991-02-01

    Transforming growth factor (TGF) beta 1 is a multifunctional cytokine with powerful effects on osteoblastic cells. Its role in the regulation of osteoclast generation and function, however, is unclear. It has been reported both to stimulate and to inhibit resorption in organ culture and to inhibit multinuclear cell formation in bone marrow cultures. We tested the effects of TGF-beta 1 on bone resorption by osteoclasts isolated from neonatal rat long bones. We found potent stimulation of osteoclastic bone resorption, mediated by osteoblastic cells, with an EC50 of 10 pg/ml, considerably lower than that of well-documented osteotropic hormones. Stimulation was not mediated by Swiss mouse 3T3 cells, a nonosteoblastic cell line. TGF-beta 1 strongly inhibited the generation of calcitonin receptor (CTR)-positive cells in mouse bone marrow cultures, but as for isolated osteoclasts, bone resorption per CTR-positive cell was increased. The inhibition of CTR-positive cell formation was associated with suppression of maturation of other bone marrow derivatives and may be related more to the known ability of TGF-beta 1 to suppress the proliferation of primitive hematopoietic cells than to a specific role of TGF-beta 1 in osteoclast generation.

  12. The type III transforming growth factor beta receptor regulates vascular and osteoblast development during palatogenesis

    PubMed Central

    Hill, Cynthia R.; Jacobs, Britni H.; Brown, Christopher B.; Barnett, Joey V.; Goudy, Steven L.

    2015-01-01

    Background Cleft palate occurs in up to 1:1000 live births and is associated with mutations in multiple genes. Palatogenesis involves a complex choreography of palatal shelf elongation, elevation, and fusion. Transforming growth factor β (TGFβ) and bone morphogenetic protein 2 (BMP2) canonical signaling is required during each stage of palate development. The type III TGFβ receptor (TGFβR3) binds all three TGFβ ligands and BMP2, but its contribution to palatogenesis is unknown. Results The role of TGFβR3 during palate formation was found to be during palatal shelf elongation and elevation. Tgfbr3-/- embryos displayed reduced palatal shelf width and height, changes in proliferation and apoptosis, and reduced vascular and osteoblast differentiation. Abnormal vascular plexus organization as well as aberrant expression of arterial (Notch1, Alk1), venous (EphB4), and lymphatic (Lyve1) markers was also observed. Decreased osteoblast differentiation factors (Runx2, alk phos, osteocalcin, col1A1, and col1A2) demonstrated poor mesenchymal cell commitment to the osteoblast lineage within the maxilla and palatal shelves in Tgfbr3-/- embryos. Additionally, in vitro bone mineralization induced by osteogenic medium (OM+BMP2) was insufficient in Tgfbr3-/- palatal mesenchyme, but mineralization was rescued by overexpression of TGFβR3. Conclusions These data reveal a critical, previously unrecognized role for TGFβR3 in vascular and osteoblast development during palatogenesis. PMID:25382630

  13. Hepatic transforming growth factor-β 1 stimulated clone-22 D1 controls systemic cholesterol metabolism☆

    PubMed Central

    Jäger, Julia; Greiner, Vera; Strzoda, Daniela; Seibert, Oksana; Niopek, Katharina; Sijmonsma, Tjeerd P.; Schäfer, Michaela; Jones, Allan; De Guia, Roldan; Martignoni, Marc; Dallinga-Thie, Geesje M.; Diaz, Mauricio B.; Hofmann, Thomas G.; Herzig, Stephan

    2014-01-01

    Disturbances in lipid homeostasis are hallmarks of severe metabolic disorders and their long-term complications, including obesity, diabetes, and atherosclerosis. Whereas elevation of triglyceride (TG)-rich very-low-density lipoproteins (VLDL) has been identified as a risk factor for cardiovascular complications, high-density lipoprotein (HDL)-associated cholesterol confers atheroprotection under obese and/or diabetic conditions. Here we show that hepatocyte-specific deficiency of transcription factor transforming growth factor β 1-stimulated clone (TSC) 22 D1 led to a substantial reduction in HDL levels in both wild-type and obese mice, mediated through the transcriptional down-regulation of the HDL formation pathway in liver. Indeed, overexpression of TSC22D1 promoted high levels of HDL cholesterol in healthy animals, and hepatic expression of TSC22D1 was found to be aberrantly regulated in disease models of opposing energy availability. The hepatic TSC22D1 transcription factor complex may thus represent an attractive target in HDL raising strategies in obesity/diabetes-related dyslipidemia and atheroprotection. PMID:24634828

  14. Cardiac fibroblasts are predisposed to convert into myocyte phenotype: Specific effect of transforming growth factor. beta

    SciTech Connect

    Eghbali, M.; Tomek, R.; Woods, C.; Bhambi, B. )

    1991-02-01

    Cardiac fibroblasts are mainly responsible for the synthesis of major extracellular matrix proteins in the heart, including fibrillar collagen types I and III and fibronectin. In this report we show that these cells, when stimulated by transforming growth factor {beta}{sub 1} (TGF-{beta}{sub 1}), acquire certain myocyte-specific properties. Cultured cardiac fibroblasts from adult rabbit heart were treated with TGF-{beta}{sub 1}, (10-15 ng/ml) for different periods of time. Northern hybridization analysis of total RNA showed that cells treated with TGF-{beta}{sub 1} became stained with a monoclonal antibody to muscle-specific actin. After treatment of quiescent cells with TGF-{beta}{sub 1}, cell proliferation (as measured by ({sup 3}H)thymidine incorporation) was moderately increased. Cultured cardiac fibroblasts at the subconfluent stage, when exposed to TGF-{beta}{sub 1} in the presence of 10% fetal bovine serum, gave rise to a second generation of slowly growing cells that expressed muscle-specific actin filaments. The findings demonstrate that cardiac fibroblasts can be made to differentiate into cells that display many characteristics of cardiac myocytes. TGF-{beta}{sub 1} seems to be a specific inducer of such conversion.

  15. Association of Transforming Growth Factor Alpha Polymorphisms with Nonsyndromic Cleft Lip and Palate in Iranian Population

    PubMed Central

    Ebadifar, Asghar; Hamedi, Roya; Khorram Khorshid, Hamid Reza; Saliminejad, Kioomars; Kamali, Koorosh; Aghakhani Moghadam, Fatemeh; Esmaeili Anvar, Nazanin; Ameli, Nazilla

    2015-01-01

    Background: Cleft lip with or without cleft palate (CL/P) is one of the most common congenital anomalies and the etiology of orofacial clefts is multifactorial. Transforming growth factor alpha (TGFA) is expressed at the medial edge epithelium of fusing palatal shelves during craniofacial development. In this study, the association of two important TGFA gene polymorphisms, BamHI (rs11466297) and RsaI (rs3732248), with CL/P was evaluated in an Iranian population. Methods: The frequencies of BamHI and RsaI variations were determined in 105 unrelated Iranian subjects with nonsyndromic CL/P and 218 control subjects using PCR and RFLP methods, and the results were compared with healthy controls. A p-value of <0.05 was considered statistically significant. Results: The BamHI AC genotype was significantly higher (p=0.016) in the patients (12.4%) than the control group (5.0%). The BamHI C allele was significantly higher (p=0.001; OR=3.4, 95% CI: 1.6–7.4) in the cases (8.0%) compared with the control group (2.5%). Conclusion: Our study showed that there was an association between the TGFA BamHI variation and nonsyndromic CL/P in Iranian population. PMID:26605011

  16. Transforming growth factor receptor type II (ec-TβR II) behaves as a halophile.

    PubMed

    Saini, Komal; Khan, M Ashhar I; Chakrapani, Sumit; Deep, Shashank

    2015-01-01

    The members of transforming growth factor β family (TGF-β) are multifunctional proteins but their main role is to control cell proliferation and differentiation. Polypeptides of TGF-β family function by binding to two related, functionally distinct transmembrane receptor kinases, first to the type II (TβR II) followed by type I receptor (TβR I). The paper describes, in details, the stability of wt-ec-TβR II under different conditions. The stability of wt-ec-TβR II was observed at different pH and salt concentration using fluorescence spectroscopy. Stability of ec-TβR II decreases with decrease in pH. Interestingly, the addition of salt increases the stability of the TβRII at pH 5.0 as observed for halophiles. Computational analysis using DELPHI suggests that this is probably due to the decrease in repulsion between negatively charged residues at surface on the addition of salt. This is further confirmed by the change in the stability of receptor on mutation of some of the residues (D32A) at surface. PMID:25316422

  17. Transforming growth factor-beta. Murine glomerular receptors and responses of isolated glomerular cells.

    PubMed Central

    MacKay, K; Striker, L J; Stauffer, J W; Doi, T; Agodoa, L Y; Striker, G E

    1989-01-01

    Proliferation of resident glomerular cells and the accumulation of mesangial matrix are histologic abnormalities which are observed in the course of many progressive glomerular diseases. We explored the potential regulatory effects of transforming growth factor-beta (TGF-beta) on these processes. We found that cultured mouse glomerular endothelial, mesangial, and epithelial cells as well as isolated intact rat glomeruli possess high-affinity receptors for TGF-beta. We also found that, although TGF-beta consistently inhibited the proliferation of glomerular endothelial and epithelial cells, it acted as a bifunctional regulator of mesangial cell proliferation. TGF-beta significantly increased the production of collagen and fibronectin by glomerular mesangial cells whereas only fibronectin production was augmented in glomerular epithelial cells. The presence of TGF-beta receptors on intact glomeruli and on each glomerular cell type and the demonstrated responsiveness of these cells to TGF-beta combine to suggest that potentially important interactions may occur between resident glomerular cells and TGF-beta in vivo. Images PMID:2539392

  18. Integration of sexual trauma in a religious narrative: Transformation, resolution and growth among contemplative nuns

    PubMed Central

    Littlewood, Roland; Leavey, Gerard

    2013-01-01

    The psychological consequences of sexual abuse are generally serious and enduring, particularly when the perpetrator is known and trusted by the survivor. This paper explores the experiences of five contemplative nuns who were sexually abused by priests and the spiritual journeys that followed. In the context of an ethnographic study of contemplative practice, participant observation and in-depth interviews were used to examine the ways that the nuns sought to make sense of their experiences through a long process of solitary introspection. The pursuit of meaning was shaped by religious beliefs relating to forgiveness, sacrifice, and salvation. Thus, trauma was transformed into a symbolic religious narrative that shaped their sense of identity. They were able to restructure core beliefs and to manage their current relationships with priests more securely. They described regaining their spiritual well-being in ways that suggest a form of posttraumatic spiritual growth. We conclude by discussing the findings in the light of the existing literature on the interaction of trauma and spirituality. PMID:23296289

  19. Metformin is a novel suppressor for transforming growth factor (TGF)-β1

    NASA Astrophysics Data System (ADS)

    Xiao, Han; Zhang, Jianshu; Xu, Zhonghe; Feng, Yenan; Zhang, Mingliang; Liu, Jianli; Chen, Ruifei; Shen, Jing; Wu, Jimin; Lu, Zhizhen; Fang, Xiaohong; Li, Jingyuan; Zhang, Youyi

    2016-06-01

    Metformin is a widely used first-line antidiabetic drug that has been shown to protect against a variety of specific diseases in addition to diabetes, including cardiovascular disorders, polycystic ovary syndrome, and cancer. However, the precise mechanisms underlying the diverse therapeutic effects of metformin remain elusive. Here, we report that transforming growth factor-β1 (TGF-β1), which is involved in the pathogenesis of numerous diseases, is a novel target of metformin. Using a surface plasmon resonance-based assay, we identified the direct binding of metformin to TGF-β1 and found that metformin inhibits [125I]-TGF-β1 binding to its receptor. Furthermore, based on molecular docking and molecular dynamics simulations, metformin was predicted to interact with TGF-β1 at its receptor-binding domain. Single-molecule force spectroscopy revealed that metformin reduces the binding probability but not the binding force of TGF-β1 to its type II receptor. Consequently, metformin suppresses type II TGF-β1 receptor dimerization upon exposure to TGF-β1, which is essential for downstream signal transduction. Thus, our results indicate that metformin is a novel TGF-β suppressor with therapeutic potential for numerous diseases in which TGF-β1 hyperfunction is indicated.

  20. Association of transforming growth-factor alpha gene polymorphisms with nonsyndromic cleft palate only (CPO)

    SciTech Connect

    Shiang, R. ); Lidral, A.C.; Ardinger, H.H.; Murray, J.C.; Romitti, P.A.; Munger, R.G.; Buetow, K.H.

    1993-10-01

    Genetic analysis and tissue-specific expression studies support a role for transforming growth-factor alpha (TGFA) in craniofacial development. Previous studies have confirmed an association of alleles for TGFA with nonsyndromic cleft lip with or without cleft palate (CL/P) in humans. The authors carried out a retrospective association study to determine whether specific allelic variants of the TGFA gene are also associated with cleft palate only (CPO). The PCR products from 12 overlapping sets of primers to the TGFA cDNA were examined by using single-strand conformational polymorphism analysis. Four DNA polymorphic sites for TGFA were identified in the 3[prime] untranslated region of the TGFA gene. These variants, as well as previously identified RFLPs for TGFA, were characterized in case and control populations for CPO by using X[sup 2] analysis. A significant association between alleles of TGFA and CPO was identified which further supports a role for this gene as one of the genetic determinants of craniofacial development. Sequence analysis of the variants disclosed a cluster of three variable sites within 30 bp of each other in the 3[prime] untranslated region previously associated with an antisense transcript. These studies extend the role for TGFA in craniofacial morphogenesis and support an interrelated mechanism underlying nonsyndromic forms of CL/P. 46 refs., 3 figs., 3 tabs.

  1. Generation of Mice With a Conditional Allele for the Transforming Growth Factor Beta3 Gene

    PubMed Central

    Doetschman, Thomas; Georgieva, Teodora; Li, Hongqi; Reed, Thomas D.; Grisham, Christina; Friel, Jacqueline; Estabrook, Mark A.; Gard, Connie; Sanford, L.P.; Azhar, Mohamad

    2013-01-01

    Summary The transforming growth factor beta (TGFβ) pathway is involved in embryonic development and several inherited and acquired human diseases. The gene for TGFβ3 (Tgfb3) encodes one of the three ligands for TGF b receptors. It is widely expressed in the embryo and its mutation or misexpression is found in human diseases. Tgfb3−/− mice die at birth from cleft palate, precluding functional studies in adults. Here, we generated mice in which exon 6 of Tgfb3 was flanked with LoxP sites (Tgfb3flox/flox). The adult mice were normal and fertile. EIIa-Cre-mediated deletion of exon 6 in Tgfb3flox/flox mice efficiently generated Tgfb3 conditional knockout (Tgfb3cko/cko) mice which died at birth from the same cleft palate defect as Tgfb3−/− mice, indicating that the conditional and knockout alleles are functionally equivalent. This Tgfb3cko allele will now enable studies of TGFβ3 function in different cell or tissue types in embryonic development and during adulthood. genesis 50:59-66, 2012. PMID:22223248

  2. Integration of sexual trauma in a religious narrative: transformation, resolution and growth among contemplative nuns.

    PubMed

    Durà-Vilà, Glòria; Littlewood, Roland; Leavey, Gerard

    2013-02-01

    The psychological consequences of sexual abuse are generally serious and enduring, particularly when the perpetrator is known and trusted by the survivor. This paper explores the experiences of five contemplative nuns who were sexually abused by priests and the spiritual journeys that followed. In the context of an ethnographic study of contemplative practice, participant observation and in-depth interviews were used to examine the ways that the nuns sought to make sense of their experiences through a long process of solitary introspection. The pursuit of meaning was shaped by religious beliefs relating to forgiveness, sacrifice, and salvation. Thus, trauma was transformed into a symbolic religious narrative that shaped their sense of identity. They were able to restructure core beliefs and to manage their current relationships with priests more securely. They described regaining their spiritual well-being in ways that suggest a form of posttraumatic spiritual growth. We conclude by discussing the findings in the light of the existing literature on the interaction of trauma and spirituality. PMID:23296289

  3. Metformin is a novel suppressor for transforming growth factor (TGF)-β1

    PubMed Central

    Xiao, Han; Zhang, Jianshu; Xu, Zhonghe; Feng, Yenan; Zhang, Mingliang; Liu, Jianli; Chen, Ruifei; Shen, Jing; Wu, Jimin; Lu, Zhizhen; Fang, Xiaohong; Li, Jingyuan; Zhang, Youyi

    2016-01-01

    Metformin is a widely used first-line antidiabetic drug that has been shown to protect against a variety of specific diseases in addition to diabetes, including cardiovascular disorders, polycystic ovary syndrome, and cancer. However, the precise mechanisms underlying the diverse therapeutic effects of metformin remain elusive. Here, we report that transforming growth factor-β1 (TGF-β1), which is involved in the pathogenesis of numerous diseases, is a novel target of metformin. Using a surface plasmon resonance-based assay, we identified the direct binding of metformin to TGF-β1 and found that metformin inhibits [125I]-TGF-β1 binding to its receptor. Furthermore, based on molecular docking and molecular dynamics simulations, metformin was predicted to interact with TGF-β1 at its receptor-binding domain. Single-molecule force spectroscopy revealed that metformin reduces the binding probability but not the binding force of TGF-β1 to its type II receptor. Consequently, metformin suppresses type II TGF-β1 receptor dimerization upon exposure to TGF-β1, which is essential for downstream signal transduction. Thus, our results indicate that metformin is a novel TGF-β suppressor with therapeutic potential for numerous diseases in which TGF-β1 hyperfunction is indicated. PMID:27349853

  4. Identification of selected microorganisms from activated sludge capable of benzothiazole and benzotriazole transformation.

    PubMed

    Kowalska, Katarzyna; Felis, Ewa

    2015-01-01

    Benzothiazole (BT) and benzotriazole (BTA) are present in the environment - especially in urban and industrial areas, usually as anthropogenic micropollutants. BT and BTA have been found in the municipal and industrial wastewater, rivers, soil, groundwater, sediments and sludge. The origins of those substances' presence in the environment are various industry branches (food, chemical, metallurgical, electrical), households and surface runoff from industrial areas. Increasingly strict regulations on water quality and the fact that the discussed compounds are poorly biodegradable, make them a serious problem in the environment. Considering this, it is important to look for environmentally friendly and socially acceptable ways to remove BT and BTA. The aim of this study was to identify microorganisms capable of BT and BTA transformation or/and degradation in aquatic environment. Selected microorganisms were isolated from activated sludge. The identification of microorganisms capable of BT and BTA removal was possible using molecular biology techniques (PCR, DNA sequencing). Among isolated microorganisms of activated sludge are bacteria potentially capable of BT and BTA biotransformation and/or removal. The most common bacteria capable of BT and BTA transformation were Rhodococcus sp., Enterobacter sp., Arthrobacter sp. They can grow in a medium with BT and BTA as the only carbon source. Microorganisms previously adapted to the presence of the studied substances at a concentration of 10 mg/l, showed a greater rate of growth of colonies on media than microorganisms unconditioned to the presence of such compounds. Results of the biodegradation test suggest that BT was degraded to a greater extent than BTA, 98-100% and 11-19%, respectively. PMID:26641641

  5. Transforming Growth Factor Beta 1 Augments Calvarial Defect Healing and Promotes Suture Regeneration

    PubMed Central

    Shakir, Sameer; MacIsaac, Zoe M.; Naran, Sanjay; Smith, Darren M.; Bykowski, Michael R.; Cray, James J.; Craft, Timothy K.; Wang, Dan; Weiss, Lee; Campbell, Phil G.; Mooney, Mark P.; Losee, Joseph E.

    2015-01-01

    Background: Repair of complex cranial defects is hindered by a paucity of appropriate donor tissue. Bone morphogenetic protein 2 (BMP2) and transforming growth factor beta 1 (TGFβ1) have been shown separately to induce bone formation through physiologically distinct mechanisms and potentially improve surgical outcome for cranial defect repair by obviating the need for donor tissue. We hypothesize that a combination of BMP2 and TGFβ1 would improve calvarial defect healing by augmenting physiologic osteogenic mechanisms. Methods/Results: Coronal suturectomies (3×15 mm) were performed in 10-day-old New Zealand White rabbits. DermaMatrix™ (3×15mm) patterned with four treatments (vehicle, 350 ng BMP2, 200 ng TGFβ1, or 350 ng BMP2+200 ng TGFβ1) was placed in suturectomy sites and rabbits were euthanized at 6 weeks of age. Two-dimensional (2D) defect healing, bone volume, and bone density were quantified by computed tomography. Regenerated bone was qualitatively assessed histologically. One-way analysis of variance revealed significant group main effects for all bone quantity measures. Analysis revealed significant differences in 2D defect healing, bone volume, and bone density between the control group and all treatment groups, but no significant differences were detected among the three growth factor treatment groups. Qualitatively, TGFβ1 treatment produced bone with morphology most similar to native bone. TGFβ1-regenerated bone contained a suture-like tissue, growing from the lateral edge of the defect margin toward the midline. Unique to the BMP2 treatment group, regenerated bone contained lacunae with chondrocytes, demonstrating the presence of endochondral ossification. Conclusions/Significance: Total healing in BMP2 and TGFβ1 treatment groups is not significantly different. The combination of BMP2+TGFβ1 did not significantly increase bone healing compared with treatment with BMP2 or TGFβ1 alone postoperatively at 4 weeks. We highlight the

  6. Follicle-restricted compartmentalization of transforming growth factor beta superfamily ligands in the feline ovary.

    PubMed

    Bristol, Sarah K; Woodruff, Teresa K

    2004-03-01

    Ovarian follicular development, follicle selection, and the process of ovulation remain poorly understood in most species. Throughout reproductive life, follicle fate is balanced between growth and apoptosis. These opposing forces are controlled by numerous endocrine, paracrine, and autocrine factors, including the ligands represented by the transforming growth factor beta (TGFbeta) superfamily. TGFbeta, activin, inhibin, bone morphometric protein (BMP), and growth differentiation factor 9 (GDF-9) are present in the ovary of many animals; however, no comprehensive analysis of the localization of each ligand or its receptors and intracellular signaling molecules during folliculogenesis has been done. The domestic cat is an ideal model for studying ovarian follicle dynamics due to an abundance of all follicle populations, including primordial stage, and the amount of readily available tissue following routine animal spaying. Additionally, knowledge of the factors involved in feline follicular development could make an important impact on in vitro maturation/in vitro fertilization (IVM/IVF) success for endangered feline species. Thus, the presence and position of TGFbeta superfamily members within the feline ovary have been evaluated in all stages of follicular development by immunolocalization. The cat inhibin alpha subunit protein is present in all follicle stages but increases in intensity within the mural granulosa cells in large antral follicles. The inhibin betaA and betaB subunit proteins, in addition to the activin type I (ActRIB) and activin type II receptor (ActRIIB), are produced in primordial and primary follicle granulosa cells. Additionally, inhibin betaA subunit is detected in the theca cells from secondary through large antral follicle size classes. GDF-9 is restricted to the oocyte of preantral and antral follicles, whereas the type II BMP receptor (BMP-RII) protein is predominantly localized to primordial- and primary-stage follicles. TGFbeta1, 2

  7. Fibroblast growth factor receptor splice variants are stable markers of oncogenic transforming growth factor β1 signaling in metastatic breast cancers

    PubMed Central

    2014-01-01

    Introduction Epithelial–mesenchymal transition (EMT) and mesenchymal–epithelial transition (MET) facilitate breast cancer (BC) metastasis; however, stable molecular changes that result as a consequence of these processes remain poorly defined. Therefore, with the hope of targeting unique aspects of metastatic tumor outgrowth, we sought to identify molecular markers that could identify tumor cells that had completed the EMT:MET cycle. Methods An in vivo reporter system for epithelial cadherin (E-cad) expression was used to quantify its regulation in metastatic BC cells during primary and metastatic tumor growth. Exogenous addition of transforming growth factor β1 (TGF-β1) was used to induce EMT in an in situ model of BC. Microarray analysis was employed to examine gene expression changes in cells chronically treated with and withdrawn from TGF-β1, thus completing one full EMT:MET cycle. Changes in fibroblast growth factor receptor type 1 (FGFR1) isoform expression were validated using PCR analyses of patient-derived tumor tissues versus matched normal tissues. FGFR1 gene expression was manipulated using short hairpin RNA depletion and cDNA rescue. Preclinical pharmacological inhibition of FGFR kinase was employed using the orally available compound BGJ-398. Results Metastatic BC cells undergo spontaneous downregulation of E-cad during primary tumor growth, and its expression subsequently returns following initiation of metastatic outgrowth. Exogenous exposure to TGF-β1 was sufficient to drive the metastasis of an otherwise in situ model of BC and was similarly associated with a depletion and return of E-cad expression during metastatic progression. BC cells treated and withdrawn from TGF-β stably upregulate a truncated FGFR1-β splice variant that lacks the outermost extracellular immunoglobulin domain. Identification of this FGFR1 splice variant was verified in metastatic human BC cell lines and patient-derived tumor samples. Expression of FGFR1-β was

  8. Expression of transforming growth factor-β (TGF-β) in chronic idiopathic cough

    PubMed Central

    Xie, Shaoping; Macedo, Patricia; Hew, Mark; Nassenstein, Christina; Lee, Kang-Yun; Chung, Kian Fan

    2009-01-01

    In patients with chronic idiopathic cough, there is a chronic inflammatory response together with evidence of airway wall remodelling and an increase in airway epithelial nerves expressing TRPV-1. We hypothesised that these changes could result from an increase in growth factors such as TGFβ and neurotrophins. We recruited 13 patients with persistent non-asthmatic cough despite specific treatment of associated primary cause(s), or without associated primary cause, and 19 normal non-coughing volunteers without cough as controls, who underwent fiberoptic bronchoscopy with bronchoalveolar lavage (BAL) and bronchial biopsies. There was a significant increase in the levels of TGFβ in BAL fluid, but not of nerve growth factor(NGF) and brain-derived nerve growth factor(BDNF) compared to normal volunteers. Levels of TFGβ gene and protein expression were assessed in bronchial biopsies. mRNA expression for TGFβ was observed in laser-captured airway smooth muscle and epithelial cells, and protein expression by immunohistochemistry was increased in ASM cells in chronic cough patients, associated with an increase in nuclear expression of the transcription factor, smad 2/3. Subbasement membrane thickness was significantly higher in cough patients compared to normal subjects and there was a positive correlation between TGF-β levels in BAL and basement membrane thickening. TGFβ in the airways may be important in the airway remodelling changes observed in chronic idiopathic cough patients, that could in turn lead to activation of the cough reflex. PMID:19463161

  9. Overexpression of transforming growth factor-alpha causes liver enlargement and increased hepatocyte proliferation in transgenic mice.

    PubMed Central

    Webber, E. M.; Wu, J. C.; Wang, L.; Merlino, G.; Fausto, N.

    1994-01-01

    Transforming growth factor-alpha (TGF-alpha) expression is associated with hepatocyte DNA replication both in vivo and in culture. Our previous work using TGF-alpha transgenic mice showed that constitutive overexpression of this growth factor in the liver causes hepatic tumors in 75 to 80% of the animals at 12 to 15 months of age. To understand the cellular events by which TGF-alpha overexpression leads to abnormal liver growth, we examined hepatocyte proliferative activity in young and old TGF-alpha transgenic mice and hepatocyte ploidy in normal, dysplastic, and neoplastic livers of these animals. At 4 weeks of age, transgenic mice had higher liver weights and liver weight/body weight ratios than non-transgenic mice of the same age and hepatocyte proliferative activity, measured by 3H-thymidine incorporation after 3- and 7-day infusion, proliferating cell nuclear antigen staining, and mitotic index determination, was 2 to 3 times higher than in controls. In both transgenic and non-transgenic mice hepatocyte proliferation declined with age but the decrease was much more pronounced in control animals, so that at 8 months of age, hepatocyte replication was 8 to 10 times higher in transgenic animals. Surprisingly, however, transgenic and non-transgenic mice at this age had similar liver weight/body weight ratios. Labeling studies done in 3-month-old animals revealed that hepatocyte turnover was much faster in transgenic than in control animals, suggesting that a homeostatic compensatory mechanism involving cell death tended to restore normal liver weight/body weight ratios in older transgenic mice. Ploidy analyses showed that at 4 weeks of age transgenic mice had a higher proportion of diploid and tetraploid hepatocytes and that the hepatocellular tumors which developed in TGF-alpha transgenic mice at 13 months of age contained a higher fraction of diploid hepatocytes than that present in adjacent tissue or in dysplastic livers. The results demonstrate that

  10. Attachment to laminin‐111 facilitates transforming growth factor β‐induced expression of matrix metalloproteinase‐3 in synovial fibroblasts

    PubMed Central

    Hoberg, Maik; Rudert, Maximilian; Pap, Thomas; Klein, Gerd; Gay, Steffen; Aicher, Wilhelm K

    2007-01-01

    Background In the synovial membrane of patients with rheumatoid arthritis (RA), a strong expression of laminins and matrix degrading proteases was reported. Aim To investigate the regulation of matrix metalloproteinases (MMPs) in synovial fibroblasts (SFs) of patients with osteoarthritis (OA) and RA by attachment to laminin‐1 (LM‐111) and in the presence or absence of costimulatory signals provided by transforming growth factor β (TGFβ). Methods SFs were seeded in laminin‐coated flasks and activated by addition of TGFβ. The expression of genes was investigated by quantitative reverse transcriptase‐polymerase chain reaction (qRT‐PCR), immunocytochemistry and ELISA, and intracellular signalling pathways by immunoblotting, and by poisoning p38MAPK by SB203580, MEK‐ERK by PD98059 and SMAD2 by A‐83‐01. Results Attachment of SF to LM‐111 did not activate the expression of MMPs, but addition of TGFβ induced a fivefold higher expression of MMP‐3. Incubation of SF on LM‐111 in the presence of TGFβ induced a significant 12‐fold higher expression of MMP‐3 mRNA, and secretion of MMP‐3 was elevated 20‐fold above controls. Functional blocking of LM‐111–integrin interaction reduced the laminin‐activated MMP‐3 expression significantly. Stimulation of SF by LM‐111 and TGFβ activated the p38MAPK, ERK and SMAD2 pathways, and inhibition of these pathways by using SB203580, PD98059 or A‐83‐01 confirmed the involvement of these pathways in the regulation of MMP‐3. Conclusion Attachment of SF to LM‐111 by itself has only minor effects on the expression of MMP‐1 or MMP‐3, but it facilitates the TGFβ‐induced expression of MMP‐3 significantly. This mode of MMP‐3 induction may therefore contribute to inflammatory joint destruction in RA independent of the proinflammatory cytokines interleukin (IL)1β or tumour necrosis factor (TNF)α. PMID:17124250

  11. Environmental Particulate (PM2.5) Augments Stiffness-Induced Alveolar Epithelial Cell Mechanoactivation of Transforming Growth Factor Beta

    PubMed Central

    Dysart, Marilyn M.; Galvis, Boris R.; Russell, Armistead G.; Barker, Thomas H.

    2014-01-01

    Dysfunctional pulmonary homeostasis and repair, including diseases such as pulmonary fibrosis (PF), chronic obstructive pulmonary disease (COPD), and tumorigenesis have been increasing over the past decade, a fact that heavily implicates environmental influences. Several investigations have suggested that in response to increased transforming growth factor - beta (TGFβ) signaling, the alveolar type II (ATII) epithelial cell undergoes phenotypic changes that may contribute to the complex pathobiology of PF. We have previously demonstrated that increased tissue stiffness associated with PF is a potent extracellular matrix (ECM) signal for epithelial cell activation of TGFβ. The work reported here explores the relationship between tissue stiffness and exposure to environmental stimuli in the activation of TGFβ. We hypothesized that exposure of ATII cells to fine particulate matter (PM2.5) will result in enhanced cell contractility, TGFβ activation, and subsequent changes to ATII cell phenotype. ATII cells were cultured on increasingly stiff substrates with or without addition of PM2.5. Exposure to PM2.5 resulted in increased activation of TGFβ, increased cell contractility, and elongation of ATII cells. Most notably, on 8 kPa substrates, a stiffness greater than normal but less than established fibrotic lung, addition of PM2.5 resulted in increased cortical cell stiffness, enhanced actin staining and cell elongation; a result not seen in the absence of PM2.5. Our work suggests that PM2.5 exposure additionally enhances the existing interaction between ECM stiffness and TGFβ that has been previously reported. Furthermore, we show that this additional enhancement is likely a consequence of intracellular reactive oxygen species (ROS) leading to increased TGFβ signaling events. These results highlight the importance of both the micromechanical and biochemical environment in lung disease initiation and suggest that individuals in early stages of lung remodeling

  12. Mitochondrial-targeted antioxidant therapy decreases transforming growth factor-β-mediated collagen production in a murine asthma model.

    PubMed

    Jaffer, Omar A; Carter, A Brent; Sanders, Philip N; Dibbern, Megan E; Winters, Christopher J; Murthy, Shubha; Ryan, Alan J; Rokita, Adam G; Prasad, Anand M; Zabner, Joseph; Kline, Joel N; Grumbach, Isabella M; Anderson, Mark E

    2015-01-01

    Asthma is a disease of acute and chronic inflammation in which cytokines play a critical role in orchestrating the allergic inflammatory response. IL-13 and transforming growth factor (TGF)-β promote fibrotic airway remodeling, a major contributor to disease severity. Improved understanding is needed, because current therapies are inadequate for suppressing development of airway fibrosis. IL-13 is known to stimulate respiratory epithelial cells to produce TGF-β, but the mechanism through which this occurs is unknown. Here, we tested the hypothesis that reactive oxygen species (ROS) are a critical signaling intermediary between IL-13 or allergen stimulation and TGF-β-dependent airway remodeling. We used cultured human bronchial epithelial cells and an in vivo mouse model of allergic asthma to map a pathway where allergens enhanced mitochondrial ROS, which is an essential upstream signal for TGF-β activation and enhanced collagen production and deposition in airway fibroblasts. We show that mitochondria in airway epithelium are an essential source of ROS that activate TGF-β expression and activity. TGF-β from airway epithelium stimulates collagen expression in fibroblasts, contributing to an early fibrotic response to allergen exposure in cultured human airway cells and in ovalbumin-challenged mice. Treatment with the mitochondrial-targeted antioxidant, (2-(2,2,6,6-Tetramethylpiperidin-1-oxyl-4-ylamino)-2-oxoethyl)triphenylphosphonium chloride (mitoTEMPO), significantly attenuated mitochondrial ROS, TGF-β, and collagen deposition in OVA-challenged mice and in cultured human epithelial cells. Our findings suggest that mitochondria are a critical source of ROS for promoting TGF-β activity that contributes to airway remodeling in allergic asthma. Mitochondrial-targeted antioxidants may be a novel approach for future asthma therapies. PMID:24988374

  13. GSK3 inactivation is involved in mitochondrial complex IV defect in transforming growth factor (TGF) {beta}1-induced senescence

    SciTech Connect

    Byun, Hae-Ok; Jung, Hyun-Jung; Seo, Yong-Hak; Lee, Young-Kyoung; Hwang, Sung-Chul; Seong Hwang, Eun; Yoon, Gyesoon

    2012-09-10

    Transforming growth factor {beta}1 (TGF {beta}1) induces Mv1Lu cell senescence by persistently producing mitochondrial reactive oxygen species (ROS) through decreased complex IV activity. Here, we investigated the molecular mechanism underlying the effect of TGF {beta}1 on mitochondrial complex IV activity. TGF {beta}1 progressively phosphorylated the negative regulatory sites of both glycogen synthase kinase 3 (GSK3) {alpha} and {beta}, corresponding well to the intracellular ROS generation profile. Pre-treatment of N-acetyl cysteine, an antioxidant, did not alter this GSK3 phosphorylation (inactivation), whereas pharmacological inhibition of GSK3 by SB415286 significantly increased mitochondrial ROS, implying that GSK3 phosphorylation is an upstream event of the ROS generation. GSK3 inhibition by SB415286 decreased complex IV activity and cellular O{sub 2} consumption rate and eventually induced senescence of Mv1Lu cell. Similar results were obtained with siRNA-mediated knockdown of GSK3. Moreover, we found that GSK3 not only exists in cytosol but also in mitochondria of Mv1Lu cell and the mitochondrial GSK3 binds complex IV subunit 6b which has no electron carrier and is topologically located in the mitochondrial intermembrane space. Involvement of subunit 6b in controlling complex IV activity and overall respiration rate was proved with siRNA-mediated knockdown of subunit 6b. Finally, TGF {beta}1 treatment decreased the binding of the subunit 6b to GSK3 and subunit 6b phosphorylation. Taken together, our results suggest that GSK3 inactivation is importantly involved in TGF {beta}1-induced complex IV defects through decreasing phosphorylation of the subunit 6b, thereby contributing to senescence-associated mitochondrial ROS generation.

  14. Endotoxin-Induced Endothelial Fibrosis Is Dependent on Expression of Transforming Growth Factors β1 and β2

    PubMed Central

    Echeverría, César; Montorfano, Ignacio; Tapia, Pablo; Riedel, Claudia; Cabello-Verrugio, Claudio

    2014-01-01

    During endotoxemia-induced inflammatory disease, bacterial endotoxins circulate in the bloodstream and interact with endothelial cells (ECs), inducing dysfunction of the ECs. We previously reported that endotoxins induce the conversion of ECs into activated fibroblasts. Through endotoxin-induced endothelial fibrosis, ECs change their morphology and their protein expression pattern, thereby suppressing endothelial markers and upregulating fibrotic proteins. The most commonly used fibrotic inducers are transforming growth factor β1 (TGF-β1) and TGF-β2. However, whether TGF-β1 and TGF-β2 participate in endotoxin-induced endothelial fibrosis remains unknown. We have shown that the endotoxin-induced endothelial fibrosis process is dependent on the TGF-β receptor, ALK5, and the activation of Smad3, a protein that is activated by ALK5 activation, thus suggesting that endotoxin elicits TGF-β production to mediate endotoxin-induced endothelial fibrosis. Therefore, we investigated the dependence of endotoxin-induced endothelial fibrosis on the expression of TGF-β1 and TGF-β2. Endotoxin-treated ECs induced the expression and secretion of TGF-β1 and TGF-β2. TGF-β1 and TGF-β2 downregulation inhibited the endotoxin-induced changes in the endothelial marker VE-cadherin and in the fibrotic proteins α-SMA and fibronectin. Thus, endotoxin induces the production of TGF-β1 and TGF-β2 as a mechanism to promote endotoxin-induced endothelial fibrosis. To the best of our knowledge, this is the first report showing that endotoxin induces endothelial fibrosis via TGF-β secretion, which represents an emerging source of vascular dysfunction. These findings contribute to understanding the molecular mechanism of endotoxin-induced endothelial fibrosis, which could be useful in the treatment of inflammatory diseases. PMID:24935972

  15. Transforming Growth Factor-β1 Downregulates Vascular Endothelial Growth Factor-D Expression in Human Lung Fibroblasts via the Jun NH2-Terminal Kinase Signaling Pathway

    PubMed Central

    Cui, Ye; Osorio, Juan C; Risquez, Cristobal; Wang, Hao; Shi, Ying; Gochuico, Bernadette R; Morse, Danielle; Rosas, Ivan O; El-Chemaly, Souheil

    2014-01-01

    Vascular endothelial growth factor (VEGF)-D, a member of the VEGF family, induces both angiogenesis and lymphangiogenesis by activating VEGF receptor-2 (VEGFR-2) and VEGFR-3 on the surface of endothelial cells. Transforming growth factor (TGF)-β1 has been shown to stimulate VEGF-A expression in human lung fibroblast via the Smad3 signaling pathway and to induce VEGF-C in human proximal tubular epithelial cells. However, the effects of TGF-β1 on VEGF-D regulation are unknown. To investigate the regulation of VEGF-D, human lung fibroblasts were studied under pro-fibrotic conditions in vitro and in idiopathic pulmonary fibrosis (IPF) lung tissue. We demonstrate that TGF-β1 downregulates VEGF-D expression in a dose- and time-dependent manner in human lung fibroblasts. This TGF-β1 effect can be abolished by inhibitors of TGF-β type I receptor kinase and Jun NH2-terminal kinase (JNK), but not by Smad3 knockdown. In addition, VEGF-D knockdown in human lung fibroblasts induces G1/S transition and promotes cell proliferation. Importantly, VEGF-D protein expression is decreased in lung homogenates from IPF patients compared with control lung. In IPF lung sections, fibroblastic foci show very weak VEGF-D immunoreactivity, whereas VEGF-D is abundantly expressed within alveolar interstitial cells in control lung. Taken together, our data identify a novel mechanism for downstream signal transduction induced by TGF-β1 in lung fibroblasts, through which they may mediate tissue remodeling in IPF. PMID:24515257

  16. Mitogenic and metabolic actions of epidermal growth factor on rat articular chondrocytes: modulation by fetal calf serum, transforming growth factor-beta, and tyrphostin.

    PubMed

    Ribault, D; Khatib, A M; Panasyuk, A; Barbara, A; Bouizar, Z; Mitrovic, R D

    1997-01-15

    The effects of human recombinant epidermal growth factor (EGF) on rat articular chondrocytes from humeral and femoral head cartilage of 21-day-old Wistar rats were analyzed. The cells were cultured under standard conditions as monolayers. Cell proliferation was studied by [3H]thymidine incorporation and determination of DNA content, proteoglycan synthesis by [35S]sulfate incorporation, and collagen synthesis by [3H]proline incorporation. The presence of specific receptors was confirmed by [125I]-EGF binding and that of EGF and EGF-receptor (EGF-R) mRNA by reverse transcription and the polymerase chain reaction. EGF (0.5-2.5 ng/ml) stimulated [3H]thymidine incorporation and increased DNA content of cultures. The effect was strongest when serum concentration was low (< or =1%) and was lost at high (> or =7.5%) serum concentrations. The EGF-induced effect on deoxynucleic acid synthesis was inhibited by transforming growth factor-beta and tyrphostin, a tyrosine kinase inhibitor that blocks the phosphorylation of tyrosine residues on EGF-R. Cultured rat articular chondrocytes possess a single class of high-affinity binding sites (Kd 0.18 nM). There were about 4.5 x 10(9) binding sites per microgram of DNA or about 37,800 binding sites per cell with 8.3 pg DNA per cell. Cultured cells contained EGF mRNA and EGF-R mRNA. Incubation of cells with EGF for 24 h decreased the EGF mRNA transcripts and increased the EGF-R mRNA levels. These findings suggest that EGF probably takes part in the regulation of chondrocyte activity under normal and presumably pathological conditions. PMID:9016808

  17. Expression and activation of erbB-2 and epidermal growth factor receptor in lung adenocarcinomas.

    PubMed Central

    Rachwal, W. J.; Bongiorno, P. F.; Orringer, M. B.; Whyte, R. I.; Ethier, S. P.; Beer, D. G.

    1995-01-01

    ErbB-2 and EGFR (epidermal growth factor receptor) are expressed in lung adenocarcinomas and associated with a poor prognosis. Immunocytochemical analysis revealed erbB-2 and EGFR coexperession as a characteristic feature of most lung adenocarcinomas, and at levels of receptor expression present in bronchial epithelial cells. In primary lung tumours and cell lines, erbB-2 detected using Western blot analysis demonstrated low-level phosphotyrosine staining of the 185 kDa band, as compared with breast cancer cell lines. A549 and A427 lung adenocarcinoma cells treated with neu differentiation factor (NDF) showed increased erbB-2 phosphotyrosine staining, but to a much lesser extent than breast cancer cells. The lung cells were examined for expression of the potential autocrine growth factors NDF and transforming growth factor alpha (TGF-alpha) by Northern blot analysis. Both NDF and TFG-alpha mRNA were abundantly expressed in the A549 cells. NDF mRNA was highest during active cell proliferation and decreased in confluent cells or after treatment with the growth-inhibitory steroid dexamethasone. Primary tumours and cell lines expressed EGFR, showing higher basal level phosphotyrosine staining than erbB-2. Treatment with NDF and EGF (epidermal growth factor) stimulated cell growth, and in A549 cells the presence of both factors provided an additive increase in cell growth. The growth stimulus that ligand-activated erbB-2 and EGFR provides to lung adenocarcinoma cells may establish a background of continued cell proliferation over which other critical transforming events may occur. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 PMID:7599067

  18. 76 FR 17145 - Agency Information Collection Activities: Business Transformation-Automated Integrated Operating...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-28

    ... SECURITY U.S. Citizenship and Immigration Services Agency Information Collection Activities: Business Transformation--Automated Integrated Operating Environment (IOE), New Information Collection; Comment Request... Operating Environment (IOE); OMB Control No. 1615-NEW. SUMMARY: USCIS is developing an automated...

  19. 76 FR 63941 - Agency Information Collection Activities: Business Transformation-Automated Integrated Operating...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-14

    ... SECURITY Citizenship and Immigration Services Agency Information Collection Activities: Business Transformation--Automated Integrated Operating Environment (IOE), New Information Collection; Comment Request..., 2011, USCIS published a 60-day notice in the Federal Register at 76 FR 1745, seeking comment on...

  20. Platelet-derived growth factor (BB homodimer), transforming growth factor-beta 1, and basic fibroblast growth factor in dermal wound healing. Neovessel and matrix formation and cessation of repair.

    PubMed Central

    Pierce, G. F.; Tarpley, J. E.; Yanagihara, D.; Mustoe, T. A.; Fox, G. M.; Thomason, A.

    1992-01-01

    Recombinant platelet-derived growth factor (BB homodimer, rPDGF-BB), transforming growth factor beta 1 (rTGF-beta 1), and basic fibroblast growth factor (rbFGF) can accelerate healing of soft tissues. However, little information is available characterizing the components of wound matrix induced by these growth factors and the molecular mechanisms underlying accelerated repair and wound maturation. In this study, the composition, quantity, and rate of extracellular matrix deposition within growth factor-treated lapine ear excisional wounds were analyzed at different stages of healing using specific histochemical and immunohistochemical stains, coupled with image analysis techniques. Single application of optimal concentrations of each growth factor accelerated normal healing by 30% (P less than 0.0003); rPDGF-BB markedly augmented early glycosaminoglycan (GAG) and fibronectin deposition, but induced significantly greater levels of collagen later in the repair process, compared with untreated wounds rTGF-beta 1 treatment led to rapidly enhanced collagen synthesis and maturation, without increased GAG deposition. In contrast, rbFGF treatment induced a predominantly angiogenic response in wounds, with a marked increase in endothelia and neovessels (P less than 0.0001), and increased wound collagenolytic activity (P less than 0.03). rbFGF-treated wounds did not evolve into collagen-containing scars and continued to accumulate only provisional matrix well past wound closure. These results provide new evidence that growth factors influence wound repair via different mechanisms: 1) rPDGF-BB accelerates deposition of provisional wound matrix; 2) rTGF-beta 1 accelerates deposition and maturation of collagen; and 3) rbFGF induces a profound monocellular angiogenic response which may lead to a marked delay in wound maturation, and the possible loss of the normal signal(s) required to stop repair. These results suggest that specific growth factors may selectively regulate

  1. Genetic transformation of Gentiana macrophylla with Agrobacterium rhizogenes: growth and production of secoiridoid glucoside gentiopicroside in transformed hairy root cultures.

    PubMed

    Tiwari, Rajesh Kumar; Trivedi, Mala; Guang, Zhang Chun; Guo, Guang-Qin; Zheng, Guo-Chang

    2007-02-01

    Hairy root cultures of Gentiana macrophylla were established by infecting the different explants four Agrobacterium rhizogenes strains namely A(4)GUS, R1000, LBA 9402 and ATCC11325, and hairy root lines were established with A. rhizogenes strain R1000 in 1/2 MS + B(5) medium. Initially, 42 independent hairy root clones were maintained and seven clones belongs to different category were evaluated for growth, morphology, integration and expression of Ri T-DNA genes, and alkaloid contents in dry root samples. On the basis of total root elongation, lateral root density and biomass accumulation on solid media, hairy root clones were separated into three categories. PCR and Southern hybridization analysis revealed both left and right T-DNA integration in the root clones and RT-PCR analysis confirmed the expression of hairy root inducible gene. GUS assay was also performed to confirm the integration of left T-DNA. The accumulation of considerable amounts of the root-specific secoiridoid glucosides gentiopicroside was observed in GM1 (T +/L and T +/R) and the GM2 (T +/L and T -/R DNA) type clones in considerably higher amount whether as two T -/L but T +/R callus-type clones (GM3) accumulated much less or only very negligible amounts of gentiopicroside. Out of four media composition the 1/2 MS + B(5) vitamin media was found most suitable. We found that initial establishment of root cultures largely depends on root:media ratio. Maximum growth rate was recorded in 1:50 root:media ratio. The maximum biomass in terms of fresh weight (33-fold) was achieved in 1/2 MS + B(5) media composition after 35 days in comparison to sixfold increase in control. The biomass increase was most abundant maximum from 15 to 30 days. Influence of A. rhizogenes strains and Ri plasmid of hairy root induction, the possible role of the T(L)-DNA and T(R)-DNA genes on growth pattern of hairy root, initial root inoculum:media ratio and effect of media composition is discussed. PMID:16972092

  2. Transforming Growth Factor β/activin signalling induces epithelial cell flattening during Drosophila oogenesis

    PubMed Central

    Brigaud, Isabelle; Duteyrat, Jean-Luc; Chlasta, Julien; Le Bail, Sandrine; Couderc, Jean-Louis; Grammont, Muriel

    2015-01-01

    ABSTRACT Although the regulation of epithelial morphogenesis is essential for the formation of tissues and organs in multicellular organisms, little is known about how signalling pathways control cell shape changes in space and time. In the Drosophila ovarian epithelium, the transition from a cuboidal to a squamous shape is accompanied by a wave of cell flattening and by the ordered remodelling of E-cadherin-based adherens junctions. We show that activation of the TGFβ pathway is crucial to determine the timing, the degree and the dynamic of cell flattening. Within these cells, TGFβ signalling controls cell-autonomously the formation of Actin filament and the localisation of activated Myosin II, indicating that internal forces are generated and used to remodel AJ and to promote cytoskeleton rearrangement. Our results also reveal that TGFβ signalling controls Notch activity and that its functions are partly executed through Notch. Thus, we demonstrate that the cells that undergo the cuboidal-to-squamous transition produce active cell-shaping mechanisms, rather than passively flattening in response to a global force generated by the growth of the underlying cells. Thus, our work on TGFβ signalling provides new insights into the mechanisms through which signal transduction cascades orchestrate cell shape changes to generate proper organ structure. PMID:25681395

  3. Effects of transforming growth factor type beta on expression of cytoskeletal proteins in endosteal mouse osteoblastic cells

    SciTech Connect

    Lomri, A.; Marie, P.J. )

    1990-01-01

    Transforming growth factor beta (TGF beta) has been shown to influence the growth and differentiation of many cell types in vitro. We have examined the effects of TGF beta on cell morphology and cytoskeletal organization in relation to parameters of cell proliferation and differentiation in endosteal osteoblastic cells isolated from mouse caudal vertebrae. Treatment of mouse osteoblastic cells cultured in serum free medium for 24 hours with TGF beta (1.5-30 ng/mL) slightly (-23%) inhibited alkaline phosphatase activity. In parallel, TGF beta (0.5-30 ng/mL, 24 hours) greatly increased cell replication as evaluated by (3H)-thymidine incorporation into DNA (157% to 325% of controls). At a median dose (1.5 ng/mL) that affected both alkaline phosphatase and DNA synthesis (235% of controls) TGF beta induced rapid (six hours) cell respreading of quiescent mouse osteoblastic cells. This effect was associated with increased polymerization of actin, alpha actinin, and tubulins, as evaluated by both biochemical and immunofluorescence methods. In addition, TGF beta (1.5 ng/mL) increased the de novo biosynthesis of actin, alpha actinin, vimentin, and tubulins, as determined by {sup 35}S methionine labeling and fractionation of cytoskeletal proteins using two-dimensional gel electrophoresis. These effects were rapid and transient, as they occurred at six hours and were reversed after 24 hours of TGF beta exposure. The results indicate that the stimulatory effect of TGF beta on DNA synthesis in endosteal mouse osteoblastic cells is associated with a transient increase in cell spreading associated with enhanced polymerization and synthesis of cytoskeletal proteins.

  4. Increased expression of transforming growth factor beta s after acute oedematous pancreatitis in rats suggests a role in pancreatic repair.

    PubMed Central

    Riesle, E; Friess, H; Zhao, L; Wagner, M; Uhl, W; Baczako, K; Gold, L I; Korc, M; Büchler, M W

    1997-01-01

    BACKGROUND: Transforming growth factor beta isoforms (TGF beta s) belong to a family of multifunctional regulators of cellular growth and differentiation. They are mitogenic and chemotactic for fibroblasts and are potent stimulators of extracellular matrix production (collagen) and deposition. Upregulation of TGF beta transcription has been reported for several in vivo systems during repair after injury. AIMS: To study the expression of the three mammalian isoforms of TGF beta (TGF beta 1-3) and their relation to collagen expression as a marker for fibroblast response in acute oedematous pancreatitis in rats. METHODS: Using northern blot analysis and immunohistochemistry, the expression and localisation of TGF beta isoforms, collagen, and amylase were analysed during the course of acute oedematous pancreatitis in rats, experimentally induced by intravenous caerulein infusion. RESULTS: Induction of acute pancreatitis resulted in a biphasic peak pattern of expression of TGF beta 1, beta 2, and beta 3 mRNA, with a pronounced increase from day 1 to day 3 (sixfold, 2.5-fold, fivefold, respectively) and again from day 5 to day 7 (three-fold, 2.3-fold, 3.5-fold, respectively). The temporal changes in TGF beta mRNA identically paralleled the expression in collagen mRNA. In contrast, amylase mRNA expression, used as a general indicator of acinar cell integrity, was slightly decreased after induction of acute pancreatitis. Immunohistochemical analysis of pancreatitis tissue showed that increased expression of TGF beta s was mainly present in the pancreatic acinar and ductal cells; this was evident within one day after pancreatitis induction. CONCLUSION: Overexpression of TGF beta s after induction of acute pancreatitis suggests a role for these proteins in pancreatic repair and remodelling. The increased levels of TGF beta s may help suppress immune activation, and may contribute to the increase in the extracellular matrix including collagen and to the repair of the

  5. Resistance to transforming growth factor β-mediated tumor suppression in melanoma: are multiple mechanisms in place?

    PubMed Central

    Lasfar, Ahmed; Cohen-Solal, Karine A.

    2010-01-01

    Resistance to transforming growth factor (TGF) β-mediated tumor suppression in melanoma appears to be a crucial step in tumor aggressiveness since it is usually coupled with the ability of TGFβ to drive the oncogenic process via autocrine and paracrine effects. In this review, we will focus mainly on the mechanisms of escape from TGFβ-induced cell cycle arrest because the mechanisms of resistance to TGFβ-mediated apoptosis are still essentially speculative. As expected, some of these mechanisms can directly affect the function of the main downstream effectors of TGFβ, Smad2 and Smad3, resulting in compromised Smad-mediated antiproliferative activity. Other mechanisms can counteract or overcome TGFβ-mediated cell cycle arrest independently of the Smads. In melanoma, some models of resistance to TGFβ have been suggested and will be described. In addition, we propose additional models of resistance taking into consideration the information available on the dysregulation of fundamental cellular effectors and signaling pathways in melanoma. PMID:20656791

  6. Accumulation of Extracellular Matrix and Developmental Dysregulation in the Pancreas by Transgenic Production of Transforming Growth Factor-β1

    PubMed Central

    Lee, Myung-Shik; Gu, Danling; Feng, Lili; Curriden, Scott; Arnush, Marc; Krahl, Troy; Gurushanthaiah, Deepak; Wilson, Curtis; Loskutoff, David L.; Fox, Howard; Sarvetnick, Nora

    1995-01-01

    Transgenic mice expressing transforming growth factor-β1 (TGF-β1) in the pancreatic β-islet cells directed by human insulin promoter were produced to study in vivo effects of TGF-β1. Fibroblast proliferation and abnormal deposition of extracellular matrix were observed from birth onward, finally replacing almost all the exocrine pancreas. Cellular infiltrates comprising macrophages and neutrophils were also observed. Plasminogen activator inhibitor was induced in the transgenic pancreas as well as fibronectin and laminin, partly explaining accumulation of extracellular matrix. TGF-β1 inhibited proliferation of acinar cells in vivo as evidenced by decreased bromodeoxyuridine incorporation. Development of pancreatic islets was dysregulated, resulting in small islet cell clusters without formation of normal adult islets; however, the overall islet cell mass was not signfifcantly diminished. Additional transgenic lines with less pronounced phenotypes had less expression of TGF-β1 transgene. These findings suggest that TGF-β1 might be a mediator of diseases associated with extracellular matrix deposition such as chronic pancreatitis, and this mouse model will be useful for further analysis of the in vivo effects of TGF-β1, including its potential for immunosuppression. Imagesp43-aFigure 2Figure 3Figure 4Figure 5Figure 6 PMID:7604884

  7. Doxazosin Treatment Attenuates Carbon Tetrachloride-Induced Liver Fibrosis in Hamsters through a Decrease in Transforming Growth Factor β Secretion

    PubMed Central

    Muñoz-Ortega, Martin Humberto; Llamas-Ramírez, Raúl Wiliberto; Romero-Delgadillo, Norma Isabel; Elías-Flores, Tania Guadalupe; de Jesus Tavares-Rodríguez, Edgar; del Rosario Campos-Esparza, María; Cervantes-García, Daniel; Muñoz-Fernández, Luis; Gerardo-Rodríguez, Martin; Ventura-Juárez, Javier

    2016-01-01

    Background/Aims The development of therapeutic strategies for the treatment of cirrhosis has become an important focus for basic and clinical researchers. Adrenergic receptor antagonists have been evaluated as antifibrotic drugs in rodent models of carbon tetrachloride (CCl4)-induced cirrhosis. The aim of the present study was to evaluate the effects of carvedilol and doxazosin on fibrosis/cirrhosis in a hamster animal model. Methods Cirrhotic-induced hamsters were treated by daily administration of carvedilol and doxazosin for 6 weeks. Hepatic function and histological evaluation were conducted by measuring biochemical markers, including total bilirubin, aspartate aminotransferase, alanine aminotransferase and albumin, and liver tissue slices. Additionally, transforming growth factor β (TGF-β) immunohistochemistry was analyzed. Results Biochemical markers revealed that hepatic function was restored after treatment with doxazosin and carvedilol. Histological evaluation showed a decrease in collagen type I deposits and TGF-β-secreting cells. Conclusions Taken together, these results suggest that the decrease in collagen type I following treatment with doxazosin or carvedilol is achieved by decreasing the profibrotic activities of TGF-β via the blockage of α1- and β-adrenergic receptor. Consequently, a diminution of fibrotic tissue in the CCl4-induced model of cirrhosis is achieved. PMID:26573293

  8. Modulation of the transforming growth factor-beta1-induced Smad phosphorylation by the extracellular matrix receptor beta1-integrin.

    PubMed

    Hamajima, Hiroshi; Ozaki, Iwata; Zhang, Hao; Iwane, Shinji; Kawaguchi, Yasunori; Eguchi, Yuichiro; Matsuhashi, Sachiko; Mizuta, Toshihiko; Matsuzaki, Koichi; Fujimoto, Kazuma

    2009-12-01

    Integrins, heterodimeric receptors for the extracellular matrix, are known to modulate transforming growth factor-beta1 (TGF-beta1)-mediated cell behavior. However, the interplay between beta1-integrin and Smad signaling, regulated by TGF-beta1, is not clearly understood. This study focuses on the alterations of the regulatory Smads (R-Smads) by TGF-beta1 in beta1-integrin-transfected HepG2 cells. The phosphorylation at the C-terminal site of R-Smads by TGF-beta1 was impaired in the beta1-integrin-transfected cells. However, the R-Smads were constitutively phosphorylated at the linker region in a MAP kinase-dependent manner. Furthermore, the expression of a mutant Smad3, that lacks the phosphorylation sites in the linker region, restored the TGF-beta1-induced Smad transcriptional activity. These results suggest that beta1-integrin impairs the TGF-beta1-mediated signals through the altered phosphorylation of the R-Smads. PMID:19885568

  9. Pin1 down-regulates transforming growth factor-beta (TGF-beta) signaling by inducing degradation of Smad proteins.

    PubMed

    Nakano, Ayako; Koinuma, Daizo; Miyazawa, Keiji; Uchida, Takafumi; Saitoh, Masao; Kawabata, Masahiro; Hanai, Jun-ichi; Akiyama, Hirotada; Abe, Masahiro; Miyazono, Kohei; Matsumoto, Toshio; Imamura, Takeshi

    2009-03-01

    Transforming growth factor-beta (TGF-beta) is crucial in numerous cellular processes, such as proliferation, differentiation, migration, and apoptosis. TGF-beta signaling is transduced by intracellular Smad proteins that are regulated by the ubiquitin-proteasome system. Smad ubiquitin regulatory factor 2 (Smurf2) prevents TGF-beta and bone morphogenetic protein signaling by interacting with Smads and inducing their ubiquitin-mediated degradation. Here we identified Pin1, a peptidylprolyl cis-trans isomerase, as a novel protein binding Smads. Pin1 interacted with Smad2 and Smad3 but not Smad4; this interaction was enhanced by the phosphorylation of (S/T)P motifs in the Smad linker region. (S/T)P motif phosphorylation also enhanced the interaction of Smad2/3 with Smurf2. Pin1 reduced Smad2/3 protein levels in a manner dependent on its peptidyl-prolyl cis-trans isomerase activity. Knockdown of Pin1 increased the protein levels of endogenous Smad2/3. In addition, Pin1 both enhanced the interaction of Smurf2 with Smads and enhanced Smad ubiquitination. Pin1 inhibited TGF-beta-induced transcription and gene expression, suggesting that Pin1 negatively regulates TGF-beta signaling by down-regulating Smad2/3 protein levels via induction of Smurf2-mediated ubiquitin-proteasomal degradation. PMID:19122240

  10. The kinases MEKK2 and MEKK3 regulate transforming growth factor-β-mediated helper T cell differentiation.

    PubMed

    Chang, Xing; Liu, Fang; Wang, Xiaofang; Lin, Aiping; Zhao, Hongyu; Su, Bing

    2011-02-25

    Mitogen-activated protein kinases (MAPKs) are key mediators of the T cell receptor (TCR) signals but their roles in T helper (Th) cell differentiation are unclear. Here we showed that the MAPK kinase kinases MEKK2 (encoded by Map3k2) and MEKK3 (encoded by Map3k3) negatively regulated transforming growth factor-β (TGF-β)-mediated Th cell differentiation. Map3k2(-/-)Map3k3(Lck-Cre/-) mice showed an abnormal accumulation of regulatory T (Treg) and Th17 cells in the periphery, consistent with Map3k2(-/-)Map3k3(Lck-Cre/-) naive CD4(+) T cells' differentiation into Treg and Th17 cells with a higher frequency than wild-type (WT) cells after TGF-β stimulation in vitro. In addition, Map3k2(-/-)Map3k3(Lck-Cre/-) mice developed more severe experimental autoimmune encephalomyelitis. Map3k2(-/-)Map3k3(Lck-Cre/-) T cells exhibited impaired phosphorylation of SMAD2 and SMAD3 proteins at their linker regions, which negatively regulated the TGF-β responses in T cells. Thus, the crosstalk between TCR-induced MAPK and the TGF-β signaling pathways is important in regulating Th cell differentiation. PMID:21333552

  11. Targeted expression of transforming growth factor-beta 1 in intracardiac grafts promotes vascular endothelial cell DNA synthesis.

    PubMed Central

    Koh, G Y; Kim, S J; Klug, M G; Park, K; Soonpaa, M H; Field, L J

    1995-01-01

    Intracardiac grafts comprised of genetically modified skeletal myoblasts were assessed for their ability to effect long-term delivery of recombinant transforming growth factor-beta (TGF-beta) to the heart. C2C12 myoblasts were stably transfected with a construct comprised of an inducible metallothionein promoter fused to a modified TGF-beta 1 cDNA. When cultured in medium supplemented with zinc sulfate, cells carrying this transgene constitutively secrete active TGF-beta 1. These genetically modified myoblasts were used to produce intracardiac grafts in syngeneic C3Heb/FeJ hosts. Viable grafts were observed as long as three months after implantation, and immunohistological analyses of mice maintained on water supplemented with zinc sulfate revealed the presence of grafted cells which stably expressed TGF-beta 1. Regions of apparent neovascularization, as evidenced by tritiated thymidine incorporation into vascular endothelial cells, were observed in the myocardium which bordered grafts expressing TGF-beta 1. The extent of vascular endothelial cell DNA synthesis could be modulated by altering dietary zinc. Similar effects on the vascular endothelial cells were not seen in mice with grafts comprised of nontransfected cells. This study indicates that genetically modified skeletal myoblast grafts can be used to effect the local, long-term delivery of recombinant molecules to the heart. Images PMID:7529257

  12. Transforming Growth Factor-β1 Signaling Represses Testicular Steroidogenesis through Cross-Talk with Orphan Nuclear Receptor Nur77

    PubMed Central

    Park, Eunsook; Song, Chin-Hee; Park, Jae-Il; Ahn, Ryun-Sup; Choi, Hueng-Sik; Ko, CheMyong; Lee, Keesook

    2014-01-01

    Transforming growth factor- β1 (TGF-β1) has been reported to inhibit luteinizing hormone (LH) mediated-steroidogenesis in testicular Leydig cells. However, the mechanism by which TGF-β1 controls the steroidogenesis in Leydig cells is not well understood. Here, we investigated the possibility that TGF-β1 represses steroidogenesis through cross-talk with the orphan nuclear receptor Nur77. Nur77, which is induced by LH/cAMP signaling, is one of major transcription factors that regulate the expression of steroidogenic genes in Leydig cells. TGF-β1 signaling inhibited cAMP-induced testosterone production and the expression of steroidogenic genes such as P450c17, StAR and 3β-HSD in mouse Leydig cells. Further, TGF-β1/ALK5 signaling repressed cAMP-induced and Nur77-activated promoter activity of steroidogenic genes. In addition, TGF-β1/ALK5-activated Smad3 repressed Nur77 transactivation of steroidogenic gene promoters by interfering with Nur77 binding to DNA. In primary Leydig cells isolated from Tgfbr2flox/flox Cyp17iCre mice, TGF-β1-mediated repression of cAMP-induced steroidogenic gene expression was significantly less than that in primary Leydig cells from Tgfbr2flox/flox mice. Taken together, these results suggest that TGF-β1/ALK5/Smad3 signaling represses the expression of steroidogenic genes via the suppression of Nur77 transactivation in testicular Leydig cells. These findings may provide a molecular mechanism involved in the TGF-β1-mediated repression of testicular steroidogenesis. PMID:25140527

  13. Orphan nuclear receptor small heterodimer partner inhibits transforming growth factor-beta signaling by repressing SMAD3 transactivation.

    PubMed

    Suh, Ji Ho; Huang, Jiansheng; Park, Yun-Yong; Seong, Hyun-A; Kim, Dongwook; Shong, Minho; Ha, Hyunjung; Lee, In-Kyu; Lee, Keesook; Wang, Li; Choi, Hueng-Sik

    2006-12-22

    Orphan nuclear receptor small heterodimer partner (SHP) is an atypical member of the nuclear receptor superfamily; SHP regulates the nuclear receptor-mediated transcription of target genes but lacks a conventional DNA binding domain. In this study, we demonstrate that SHP represses transforming growth factor-beta (TGF-beta)-induced gene expression through a direct interaction with Smad, a transducer of TGF-beta signaling. Transient transfection studies demonstrate that SHP represses Smad3-induced transcription. In vivo and in vitro protein interaction assays revealed that SHP directly interacts with Smad2 and Smad3 but not with Smad4. Mapping of domains mediating the interaction between SHP and Smad3 showed that the entire N-terminal domain (1-159 amino acids) of SHP and the linker domain of Smad3 are involved in this interaction. In vitro glutathione S-transferase pulldown competition experiments revealed the SHP-mediated repression of Smad3 transactivation through competition with its co-activator p300. SHP also inhibits the activation of endogenous TGF-beta-responsive gene promoters, the p21, Smad7, and plasminogen activator inhibitor-1 (PAI-1) promoters. Moreover, adenovirus-mediated overexpression of SHP decreases PAI-1 mRNA levels, and down-regulation of SHP by a small interfering RNA increases both the transactivation of Smad3 and the PAI-1 mRNA levels. Finally, the PAI-1 gene is expressed in SHP(-/-) mouse hepatocytes at a higher level than in normal hepatocytes. Taken together, these data indicate that SHP is a novel co-regulator of Smad3, and this study provides new insights into regulation of TGF-beta signaling. PMID:17074765

  14. miR-140-5p regulates adipocyte differentiation by targeting transforming growth factor-β signaling.

    PubMed

    Zhang, Xin; Chang, Ailing; Li, Yongmei; Gao, Yifei; Wang, Haixiao; Ma, Zhongshu; Li, Xiaoxia; Wang, Baoli

    2015-01-01

    Recent emerging studies of miRNAs in adipocyte commitment provide new insights to understand the molecular basis of adipogenesis. The current study indicated that miR-140-5p was altered in primary cultured marrow stromal cells and established progenitor lines after adipogenic and/or osteogenic treatment. miR-140-5p was increased in adipose tissue in db/db obese mice vs. lean mice. Supplementing miR-140-5p activity induced stromal cell ST2 and preadipocyte 3T3-L1 to differentiate into mature adipocytes. Conversely, inhibition of the endogenous miR-140-5p repressed ST2 and 3T3-L1 to fully differentiate. By contrast, knockdown of the endogenous miR-140-5p enhanced osteoblast differentiation. Transforming growth factor-β receptor I (Tgfbr1) was shown to be a direct target of miR-140-5p. Supplementing miR-140-5p in ST2 reduced the level of TGFBR1 protein, while suppression of endogenous miR-140-5p increased TGFBR1. Overexpression of Tgfbr1 inhibited, whereas knockdown of Tgfbr1 promoted adipogenic differentiation of ST2 cells. Further investigation of mechanisms that control miR-140-5p expression revealed that C/EBPα induced transcriptional activity of the miR-140-5p promoter. Removal of the putative response element of C/EBP from the promoter abolished the enhancement of the promoter activity by C/EBPα, suggesting that C/EBPα transcriptionally controls miR-140-5p expression. Taken together, our study provides evidences that miR-140-5p regulates adipocyte differentiation through a C/EBP/miR-140-5p/TGFBR1 regulatory feedback loop. PMID:26657345

  15. MEK inhibition prevents tumour-shed transforming growth factor-β-induced T-regulatory cell augmentation in tumour milieu.

    PubMed

    Hossain, Dewan M S; Panda, Abir K; Chakrabarty, Sreeparna; Bhattacharjee, Pushpak; Kajal, Kirti; Mohanty, Suchismita; Sarkar, Irene; Sarkar, Diptendra K; Kar, Santosh K; Sa, Gaurisankar

    2015-04-01

    Tumour progression is associated with immune-suppressive conditions that facilitate the escape of tumour cells from the regimen of immune cells, subsequently paralysing the host defence mechanisms. Induction of CD4(+)  CD25(+)  FoxP3(+) T regulatory (Treg) cells has been implicated in the tumour immune escape mechanism, although the novel anti-cancer treatment strategies targeting Treg cells remain unknown. The focus of this study is to define the interaction between tumour and immune system, i.e. how immune tolerance starts and gradually leads to the induction of adaptive Treg cells in the tumour microenvironment. Our study identified hyperactivated mitogen-activated protein kinase kinase (MEK)/extracellular signal-regulated kinase (ERK) -signalling as a potential target for reversing Treg cell augmentation in breast cancer patients. In more mechanistic detail, pharmacological inhibitors of MEK/ERK signalling inhibited transforming growth factor-β (TGF-β) production in tumour cells that essentially blocked TGF-β-SMAD3/SMAD4-mediated induction of CD25/interleukin-2 receptor α on CD4(+) T-cell surface. As a result high-affinity binding of interleukin-2 on those cells was prohibited, causing lack of Janus kinase 1 (JAK1)/JAK3-mediated signal transducer and activator of transcription 3 (STAT3)/STAT5 activation required for FoxP3 expression. Finally, for a more radical approach towards a safe MEK inhibitor, we validate the potential of multi-kinase inhibitor curcumin, especially the nano-curcumin made out of pure curcumin with greater bioavailability; in repealing tumour-shed TGF-β-induced Treg cell augmentation. PMID:25284464

  16. Cooperation of the ErbB2 receptor and transforming growth factor β in induction of migration and invasion in mammary epithelial cells

    PubMed Central

    Seton-Rogers, Sarah E.; Lu, Yu; Hines, Lisa M.; Koundinya, Malvika; LaBaer, Joshua; Muthuswamy, Senthil K.; Brugge, Joan S.

    2004-01-01

    MCF10A mammary epithelial cells form growth-arrested structures when cultured in three-dimensional basement membrane gels. Activation of the receptor tyrosine kinase ErbB2 induces formation of proliferative structures that share properties with noninvasive early stage lesions. We conducted a genetic screen to identify cDNAs that can cooperate with ErbB2 to induce migration in these cells, with the hypothesis that they would represent candidate “second hits” in the development of invasive breast carcinomas. We found that expression of transforming growth factor (TGF)β1 and TGFβ3 in cells expressing activated ErbB2 induces migration in transwell chambers and invasive behavior in both basement membrane cultures and invasion chambers. The ability of ErbB2 to cooperate with TGFβ correlated with sustained, elevated activation of extracellular signal-regulated kinase (Erk)-mitogen-activated protein kinase. Pharmacological reduction of Erk activity inhibited the cooperative effect of TGFβ and ErbB2 on migration and expression of activated Erk kinase was sufficient to cooperate with TGFβ to induce migration and invasion, suggesting that sustained Erk activation is critical for ErbB2/TGFβ cooperation. In addition, we show that costimulation of ErbB2 and TGFβ induces autocrine secretion of factors that are sufficient to induce migration, but not invasion, by means of both epidermal growth factor receptor-dependent and -independent processes. These results support the role of TGFβ as a pro-invasion factor in the progression of breast cancers with activated ErbB2 and suggest that activation of the Erk and epidermal growth factor receptor pathways are key in mediating these events. PMID:14739340

  17. Effects of transforming growth factor-beta on long-term human cord blood monocyte cultures

    SciTech Connect

    Orcel, P.; Bielakoff, J.; De Vernejoul, M.C. )

    1990-02-01

    Transforming growth factor-beta (TGF-beta) modulates growth and differentiation in many cell types and is abundant in bone matrix. We recently showed that human cord blood monocytes cultured in the presence of 1,25(OH)2D3 acquire some features of osteoclast precursors. Since TGF-beta has been shown to influence bone resorption in organ culture, we have studied the effect of TGF-beta (1-1,000 pg/ml) on cord blood monocyte cultures. These cells were cultured on plastic substrate during 3 weeks in the presence of 20% horse serum and 10(-9) M 1,25(OH)2D3. TGF-beta, from a concentration of 10 pg/ml in the culture medium, decreased in a dose dependent manner the formation of multinucleated cells. At a concentration of TGF-beta of 1 ng/ml, the multinucleated cells were reduced to 2.1% +/- 0.3%, compared to 19.3% +/- 1.5% in control cultures. TGF-beta inhibited in a dose-dependent manner the proliferation of cord blood monocytes as assessed by 3H-thymidine incorporation at 7 and 14 days of culture. The fusion index was also decreased by 3 weeks of treatment with TGF-beta. Indomethacin did not reverse the inhibitory effects of TGF-beta. The expression of the osteoclastic phenotype was assessed using two different antibodies: 23C6, a monoclonal antibody directed against the vitronectin receptor, which is highly expressed by osteoclasts but not by adult monocytes, and an antibody to HLA-DR, which is not present on osteoclast. TGF-beta decreased the expression of HLA-DR and increased in a dose-dependent manner the proportion of 23C6-labeled cells; these results suggest that TGF-beta could modulate a differentiation effect to the osteoclastic phenotype. However, when cord blood monocytes were cultured on devitalized rat calvariae prelabeled with 45Ca, TGF-beta did not induce any 45Ca release from bone cultured with monocytes.

  18. Hydrogen Sulfide Inhibits Transforming Growth Factor-β1-Induced EMT via Wnt/Catenin Pathway

    PubMed Central

    Tao, Jie; Lan, Zhen; Hei, Hongya; Tian, Lulu; Pan, Wanma; Wang, Li; Zhang, Xuemei

    2016-01-01

    Hydrogen sulfide (H2S) has anti-fibrotic potential in lung, kidney and other organs. The exogenous H2S is released from sodium hydrosulfide (NaHS) and can influence the renal fibrosis by blocking the differentiation of quiescent renal fibroblasts to myofibroblasts. But whether H2S affects renal epithelial-to-mesenchymal transition (EMT) and the underlying mechanisms remain unknown. Our study is aimed at investigating the in vitro effects of H2S on transforming growth factor-β1 (TGF-β1)-induced EMT in renal tubular epithelial cells (HK-2 cells) and the associated mechanisms. The induced EMT is assessed by Western blotting analysis on the expressions of α-SMA, E-cadherin and fibronectin. HK-2 cells were treated with NaHS before incubating with TGF-β1 to investigate its effect on EMT and the related molecular mechanism. Results demonstrated that NaHS decreased the expression of α-SMA and fibronectin, and increased the expression of E-cadherin. NaHS reduced the expression of TGF-β receptor type I (TβR I) and TGF-β receptor type II (TβR II). In addition, NaHS attenuated TGF-β1-induced increase of β-catenin expression and ERK phosphorylation. Moreover, it inhibited the TGF-β1-induced nuclear translocation of ββ-catenin. These effects of NaHS on fibronectin, E-cadherin and TβR I were abolished by the ERK inhibitor U0126 or β-catenin inhibitor XAV939, or β-catenin siRNA interference. We get the conclusion that NaHS attenuated TGF-β1-induced EMT in HK-2 cells through both ERK-dependent and β-catenin-dependent pathways. PMID:26760502

  19. Genetic variation in Transforming Growth Factor beta 1 and mammographic density in Singapore Chinese women

    PubMed Central

    Lee, Eunjung; Van den Berg, David; Hsu, Chris; Ursin, Giske; Koh, Woon-Puay; Yuan, Jian-Min; Stram, Daniel O.; Yu, Mimi C.; Wu, Anna H.

    2013-01-01

    Transforming growth factor-beta (TGF-β) plays a critical role in normal mammary development and morphogenesis. Decreased TGF-β signaling has been associated with increased mammographic density. Percent mammographic density (PMD) adjusted for age and body mass index (BMI) is a strong risk factor and predictor of breast cancer risk. PMD is highly heritable, but few genetic determinants have been identified. We investigated the association between genetic variation in TGFB1 and PMD using a cross-sectional study of 2,038 women who were members of the population-based Singapore Chinese Health Study cohort. We assessed PMD using a computer-assisted method. We used linear regression to examine the association between 9 tagging SNPs of TGFB1 and PMD and their interaction with parity, adjusting for age, BMI, and dialect group. We calculated ‘P-values adjusted for correlated tests’ (PACT) to account for multiple testing. The strongest association was observed for rs2241716. Adjusted PMD was higher by 1.5% per minor allele (PACT =0.04). When stratifying by parity, this association was limited to nulliparous women. For nulliparous women, adjusted PMD was higher by 8.6% per minor allele (PACT=0.003; P for interaction with parity=0.002). Three additional TGFB1 tagging SNPs, which were in linkage disequilibrium with rs2241716, were statistically significantly associated with adjusted PMD (PACT<0.05) for nulliparous women. However, none of these three SNPs showed statistically significant association after adjusting for rs2241716. Our data support that TGFB1 genetic variation may be an important genetic determinant of mammographic density measure that predicts breast cancer risk, particularly in nulliparous women. PMID:23333936

  20. Transforming growth factor-β mediates endothelial dysfunction in rats during high salt intake.

    PubMed

    Feng, Wenguang; Ying, Wei-Zhong; Aaron, Kristal J; Sanders, Paul W

    2015-12-15

    Endothelial dysfunction has been shown to be predictive of subsequent cardiovascular events and death. Through a mechanism that is incompletely understood, increased dietary salt intake promotes endothelial dysfunction in healthy, salt-resistant humans. The present study tested the hypothesis that dietary salt-induced transforming growth factor (TGF)-β promoted endothelial dysfunction and salt-dependent changes in blood pressure (BP). Sprague-Dawley rats that received diets containing 0.3% NaCl [low salt (LS)] or 8.0% NaCl [high salt (HS)] were treated with vehicle or SB-525334, a specific inhibitor of TGF-β receptor I/activin receptor-like kinase 5, beginning on day 5. BP was monitored using radiotelemetry in four groups of rats (LS, LS + SB-525334, HS, and HS + SB-525334) for up to 14 days. By day 14 of the study, mean daytime systolic BP and mean pulse pressure of the HS group treated with vehicle was greater than those in the other three groups; mean daytime systolic BP and pulse pressure of the HS + SB-525334 group did not differ from the LS and LS + SB-525334-treated groups. Whereas mean systolic BP, mean diastolic BP, and mean arterial pressure did not differ among the groups on the seventh day of the study, endothelium-dependent vasorelaxation was impaired specifically in the HS group; treatment with the activin receptor-like kinase 5 inhibitor prevented the dietary HS intake-induced increases in phospho-Smad2 (Ser(465/467)) and NADPH oxidase-4 in endothelial lysates and normalized endothelial function. These findings suggest that HS-induced endothelial dysfunction and the development of salt-dependent increases in BP were related to endothelial TGF-β signaling. PMID:26447221

  1. Dedifferentiation of Immortalized Human Podocytes in Response to Transforming Growth Factor-β

    PubMed Central

    Herman-Edelstein, Michal; Thomas, Merlin C.; Thallas-Bonke, Vicki; Saleem, Moin; Cooper, Mark E.; Kantharidis, Phillip

    2011-01-01

    OBJECTIVE Diabetic nephropathy is associated with dedifferentiation of podocytes, losing the specialized features required for efficient glomerular function and acquiring a number of profibrotic, proinflammatory, and proliferative features. These result from tight junction and cytoskeletal rearrangement, augmented proliferation, and apoptosis. RESEARCH DESIGN AND METHODS Experiments were performed in conditionally immortalized human podocytes developed by transfection with the temperature-sensitive SV40-T gene. Cells were then cultured in the presence of transforming growth factor (TGF)-β1 or angiotensin II in the presence or absence of a selective inhibitor of the TGF-β type I receptor kinase, SB-431542. Gene and protein expression were then examined by real-time RT-PCR and immunofluorescence, and correlated with changes observed in vivo in experimental diabetes. RESULTS Treatment of cells with TGF-β1 resulted in dynamic changes in their morphology, starting with retraction and shortening of foot processes and finishing with the formation of broad and complex tight junctions between adjacent podocytes. This dedifferentiation was also associated with dose- and time-dependent reduction in the expression of glomerular epithelial markers (nephrin, p-cadherin, zonnula occludens-1) and increased expression of mesenchymal markers (α−smooth muscle actin, vimentin, nestin), matrix components (fibronectin, collagen I, and collagen IV α3), cellular proliferation, and apoptosis. The induction of diabetes in mice was also associated with similar changes in morphology, protein expression, and proliferation in glomerular podocytes. CONCLUSIONS In response to TGF-β and other TGF-dependent stimuli, mature podocytes undergo dedifferentiation that leads to effacement of foot processes, morphologic flattening, and increased formation of intercellular tight junctions. This simplification of their phenotype to a more embryonic form is also associated with reentry of mature

  2. Transforming growth factor-β3 promotes facial nerve injury repair in rabbits

    PubMed Central

    WANG, YANMEI; ZHAO, XINXIANG; HUOJIA, MUHTER; XU, HUI; ZHUANG, YOUMEI

    2016-01-01

    The present study investigated the effects of transforming growth factor (TGF)-β3 on the regeneration of facial nerves in rabbits. A total of 20 adult rabbits were randomly divided into three equal groups: Normal control (n=10), surgical control (n=10) and TGF-β3 treatment (n=10). The total number and diameter of the regenerated nerve fibers was significantly increased in the TGF-β3 treatment group, as compared with in the surgical control group (P<0.01). Furthermore, in the TGF-β3 treatment group, the epineurial repair of the facial nerves was intact and the nerve fibers, which were arranged in neat rows, were morphologically intact with visible myelin swelling. However, in the surgical control group, the epineurial repair was incomplete, as demonstrated by: Atrophic nerve fibers, partially disappeared axons and myelin of uneven thickness with fuzzy borders. Electron microscopy demonstrated that the regenerated fibers in the TGF-β3 treatment group were predominantly myelinated, with clear-layered myelin sheath structures and axoplasms rich in organelles. Although typical layered myelin sheath structures were observed in the surgical control group, the myelin sheaths of the myelinated nerve fibers were poorly developed and few organelles were detected in the axoplasms. Neuro-electrophysiological examination demonstrated that, as compared with the surgical control group, the latency period of the action potentials in the TGF-β3 treatment group were shorter, whereas the stimulus amplitudes of the action potentials were significantly increased (P<0.01). The results of the present study suggest that TGF-β3 may improve the regeneration of facial nerves following trauma or injury. PMID:26997982

  3. Transforming Growth Factor-β2 Induces Bronchial Epithelial Mucin Expression in Asthma

    PubMed Central

    Chu, Hong Wei; Balzar, Silvana; Seedorf, Gregory J.; Westcott, Jay Y.; Trudeau, John B.; Silkoff, Phil; Wenzel, Sally E.

    2004-01-01

    The transforming growth factor (TGF)-β family is important for tissue repair in pathological conditions including asthma. However, little is known about the impact of either TGF-β1 or TGF-β2 on asthmatic airway epithelial mucin expression. We evaluated bronchial epithelial TGF-β1 and TGF-β2 expression and their effects on mucin expression, and the role of TGF-β1 or TGF-β2 in interleukin (IL)-13-induced mucin expression. Epithelial TGF-β1, TGF-β2, and mucin expression were evaluated in endobronchial biopsies from asthmatics and normal subjects. The effects of TGF-β1 or TGF-β2 on mucin MUC5AC protein and mRNA expression, and the impact of IL-13 on epithelial TGF-β1, TGF-β2, and MUC5AC were determined in cultured bronchial epithelial cells from endobronchial brushings of both subject groups. In biopsy tissue, epithelial TGF-β2 expression levels were higher than TGF-β1 in both asthmatics and normals. TGF-β2, but not TGF-β1, was increased in asthmatics compared with normals, and significantly correlated with mucin expression. TGF-β2, but not TGF-β1, increased mucin expression in cultured epithelial cells from both subject groups. IL-13 increased the release of TGF-β2, but not TGF-β1, from epithelial cells. A neutralizing TGF-β2 antibody partially inhibited IL-13-induced mucin expression. These data suggest that TGF-β2 production by asthmatic bronchial epithelial cells may increase airway mucin expression. IL-13-induced mucin expression may occur in part through TGF-β2 up-regulation. PMID:15466377

  4. Transforming growth factor-beta2 induces bronchial epithelial mucin expression in asthma.

    PubMed

    Chu, Hong Wei; Balzar, Silvana; Seedorf, Gregory J; Westcott, Jay Y; Trudeau, John B; Silkoff, Phil; Wenzel, Sally E

    2004-10-01

    The transforming growth factor (TGF)-beta family is important for tissue repair in pathological conditions including asthma. However, little is known about the impact of either TGF-beta1 or TGF-beta2 on asthmatic airway epithelial mucin expression. We evaluated bronchial epithelial TGF-beta1 and TGF-beta2 expression and their effects on mucin expression, and the role of TGF-beta1 or TGF-beta2 in interleukin (IL)-13-induced mucin expression. Epithelial TGF-beta1, TGF-beta2, and mucin expression were evaluated in endobronchial biopsies from asthmatics and normal subjects. The effects of TGF-beta1 or TGF-beta2 on mucin MUC5AC protein and mRNA expression, and the impact of IL-13 on epithelial TGF-beta1, TGF-beta2, and MUC5AC were determined in cultured bronchial epithelial cells from endobronchial brushings of both subject groups. In biopsy tissue, epithelial TGF-beta2 expression levels were higher than TGF-beta1 in both asthmatics and normals. TGF-beta2, but not TGF-beta1, was increased in asthmatics compared with normals, and significantly correlated with mucin expression. TGF-beta2, but not TGF-beta1, increased mucin expression in cultured epithelial cells from both subject groups. IL-13 increased the release of TGF-beta2, but not TGF-beta1, from epithelial cells. A neutralizing TGF-beta2 antibody partially inhibited IL-13-induced mucin expression. These data suggest that TGF-beta2 production by asthmatic bronchial epithelial cells may increase airway mucin expression. IL-13-induced mucin expression may occur in part through TGF-beta2 up-regulation. PMID:15466377

  5. Orofacial clefts, parental cigarette smoking, and transforming growth factor-alpha gene variants

    SciTech Connect

    Shaw, G.M.; Wasserman, C.R.; O`Malley, C.D.

    1996-03-01

    Results of studies determine whether women who smoke during early pregnancy are at increased risk of delivering infants with orofacial clefts have been mixed, and recently a gene-environment interaction between maternal smoking, transforming growth factor-alpha (TGFa), and clefting has been reported. Using a large population-based case-control study, we investigated whether parental periconceptional cigarette smoking was associated with an increased risk for having offspring with orofacial clefts. We also investigated the influence of genetic variation of the TGFa locus on the relation between smoking and clefting. Parental smoking information was obtained from telephone interviews with mothers of 731 (84.7% of eligible) orofacial cleft case infants and with mothers of 734 (78.2%) nonmalformed control infants. DNA was obtained from newborn screening blood spots and genotyped for the allelic variants of TGFa. We found that risks associated with maternal smoking were most elevated for isolated cleft lip with or without cleft palate, (odds ratio 2.1 [95% confidence interval 1.3-3.6]) and for isolated cleft palate (odds ratio 2.2 [1.1-4.5]) when mothers smoked {ge} 20 cigarrettes/d. These risks for white infants ranged from 3-fold to 11-fold across phenotypic groups. Paternal smoking was not associated with clefting among the offspring of nonsmoking mothers, and passive smoke exposures were associated with at most slightly increased risks. This study offers evidence that the risk for orofacial clefting in infants may be influenced by maternal smoke exposures alone as well as in combination (gene-environment interaction) with the presence of the uncommon TGFa allele. 56 refs., 5 tabs.

  6. v-Crk activates the phosphoinositide 3-kinase/AKT pathway in transformation

    PubMed Central

    Akagi, Tsuyoshi; Shishido, Tomoyuki; Murata, Kazutaka; Hanafusa, Hidesaburo

    2000-01-01

    v-Crk induces cellular tyrosine phosphorylation and transformation of chicken embryo fibroblasts (CEF). We studied the molecular mechanism of the v-Crk-induced transformation. Experiments with Src homology (SH)2 and SH3 domain mutants revealed that the induction of tyrosine phosphorylation of cellular proteins requires only the SH2 domain, but both the SH2 and SH3 domains are required for complete transformation. Analysis of three well defined signaling pathways, the mitogen-activated protein kinase (MAPK) pathway, the Jun N-terminal kinase (JNK) pathway, and the phosphoinositide 3-kinase (PI3K)/AKT pathway, demonstrated that only the PI3K/AKT pathway is constitutively activated in v-Crk-transformed CEF. Both the SH2 and SH3 domains are required for this activation of the PI3K/AKT pathway in CEF. We also found that the colony formation of CEF is strongly induced by a constitutively active PI3K mutant, and that a PI3K inhibitor, LY294002, suppresses the v-Crk-induced transformation. These results strongly suggest that constitutive activation of the PI3K/AKT pathway plays an essential role in v-Crk-induced transformation of CEF. PMID:10852971

  7. Activity Theory and the Transformation of Pedagogic Practice

    ERIC Educational Resources Information Center

    Yamazumi, Katsuhiro

    2006-01-01

    Today, work and other societal practices are experiencing accelerating paradigm shifts from mass-production-based systems toward new systems based on networking between organizations, collaboration, and partnerships. This shift requires new paradigms in the fields of education, learning, and development. As human activity quickly changes to…

  8. Transformation of Traditional Vocabulary Exercises into Collaborative Writing Activity

    ERIC Educational Resources Information Center

    Zheng, Jian-feng

    2010-01-01

    In the reading course, especially the so-called intensive reading course or integrative English reading course, there are some vocabulary exercises which intend to consolidate the active vocabulary emerging in the reading passages. Mostly, these exercises are in the form of blank-filling or rewriting sentences with the words given. The problem…

  9. Rat testicular germ cells and sertoli cells release different types of bioactive transforming growth factor beta in vitro

    PubMed Central

    Haagmans, Bart L; Hoogerbrugge, Jos W; Themmen, Axel PN; Teerds, Katja J

    2003-01-01

    Several in vivo studies have reported the presence of immunoreactive transforming growth factor-β's (TGF-β's) in testicular cells at defined stages of their differentiation. The most pronounced changes in TGF-β1 and TGF-β2 immunoreactivity occurred during spermatogenesis. In the present study we have investigated whether germ cells and Sertoli cells are able to secrete bioactive TGF-β's in vitro, using the CCl64 mink lung epithelial cell line as bioassay for the measurement of TGF-β. In cellular lysates, TGF-β bioactivity was only observed following heat-treatment, indicating that within these cells TGF-β is present in a latent form. To our surprise, active TGF-β could be detected in the culture supernatant of germ cells and Sertoli cells without prior heat-treatment. This suggests that these cells not only produce and release TGF-β in a latent form, but that they also release a factor which can convert latent TGF-β into its active form. Following heat-activation of these culture supernatant's, total TGF-β bioactivity increased 6- to 9-fold. Spermatocytes are the cell type that releases most bioactive TGF-β during a 24 h culture period, although round and elongated spermatids and Sertoli cells also secrete significant amounts of TGF-β. The biological activity of TGF-β could be inhibited by neutralizing antibodies against TGF-β1 (spermatocytes and round spermatids) and TGF-β2 (round and elongating spermatids). TGF-β activity in the Sertoli cell culture supernatant was inhibited slightly by either the TGF-β1 and TGF-β2 neutralizing antibody. These in vitro data suggest that germ cells and Sertoli cells release latent TGF-β's. Following secretion, the TGF-β's are converted to a biological active form that can interact with specific TGF-β receptors. These results strengthen the hypothesis that TGF-β's may play a physiological role in germ cell proliferation/differentiation and Sertoli cell function. PMID:12646048

  10. Platelet-activating factor promotes motility in breast cancer cells and disrupts non-transformed breast acinar structures.

    PubMed

    Anandi, V Libi; Ashiq, K A; Nitheesh, K; Lahiri, M

    2016-01-01

    A plethora of studies have demonstrated that chronic inflammatory microenvironment influences the genesis and progression of tumors. Such microenvironments are enriched with various lipid mediators. Platelet activating factor (PAF, 1-alkyl-2-acetyl-sn-glycero-3-phosphocholine) is one such lipid mediator that is secreted by different immune cell types during inflammation and by breast cancer cells upon stimulation with growth factors. Overexpression of PAF-receptor has also been observed in many other cancers. Here we report the possible roles of PAF in tumor initiation and progression. MCF10A, a non-transformed and non-malignant mammary epithelial cell line, when grown as 3D 'on-top' cultures form spheroids that have a distinct hollow lumen surrounded by a monolayer of epithelial cells. Exposure of these spheroids to PAF resulted in the formation of large deformed acinar structures with disrupted lumen, implying transformation. We then examined the response of transformed cells such as MDA-MB 231 to stimulation with PAF. We observed collective cell migration as well as motility at the single cell level on PAF induction, suggesting its role during metastasis. This increase in collective cell migration is mediated via PI3-kinase and/or JNK pathway and is independent of the MAP-kinase pathway. Taken together this study signifies a novel role of PAF in inducing transformation of non-tumorigenic cells and the vital role in promotion of breast cancer cell migration. PMID:26531049

  11. T24 human bladder carcinoma cells with activated Ha-ras protooncogene: Nontumorigenic cells susceptible to malignant transformation with carcinogen

    SciTech Connect

    Senger, D.R.; Perruzzi, C.A.; Ali, I.U. )

    1988-07-01

    A comparative analysis of T24 human bladder carcinoma cells and N-methyl-N{prime}-nitro-N-nitrosoguanidine (MeNNG)-transformed derivatives (MeNNG-T24) revealed the following: (i) The presence of an activated c-Ha-ras gene (in the absence of the normal allele) is sufficient to confer upon T24 cells a tumor-associated phenotype. (ii) MeNNG-transformed T24 cells not only acquire tumor-associated (in vitro) traits (growth in soft agar and rhodamine retention) but, are highly tumorigenic in nude mice. (iii) It is possible to render T24 cells tumorigenic by chemical transformation; therefore, the reason that T24 cells lack tumorigenicity is not because of possible incompatibilities between these cells and nude mice but, in fact, because T24 cells are not malignant. (iv) The loss of expression of a transformation-related M{sub r} 67,000 phosphoprotein by MeNNG-T24 cells after explanation of these cells from nude mouse tumors to in vitro culture indicates that culture conditions can be responsible for rapid phenotypic conversion of human tumor cell lines.

  12. Omega 3 but not omega 6 fatty acids inhibit AP-1 activity and cell transformation in JB6 cells

    PubMed Central

    Liu, Guangming; Bibus, Douglas M.; Bode, Ann M.; Ma, Wei-Ya; Holman, Ralph T.; Dong, Zigang

    2001-01-01

    Epidemiological and animal-based investigations have indicated that the development of skin cancer is in part associated with poor dietary practices. Lipid content and subsequently the derived fatty acid composition of the diet are believed to play a major role in the development of tumorigenesis. Omega 3 (ω3) fatty acids, including docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), can effectively reduce the risk of skin cancer whereas omega 6 (ω6) fatty acids such as arachidonic acid (AA) reportedly promote risk. To investigate the effects of fatty acids on tumorigenesis, we performed experiments to examine the effects of the ω3 fatty acids EPA and DHA and of the ω6 fatty acid AA on phorbol 12-tetradecanoate 13-acetate (TPA)-induced or epidermal growth factor (EGF)-induced transcription activator protein 1 (AP-1) transactivation and on the subsequent cellular transformation in a mouse epidermal JB6 cell model. DHA treatment resulted in marked inhibition of TPA- and EGF-induced cell transformation by inhibiting AP-1 transactivation. EPA treatment also inhibited TPA-induced AP-1 transactivation and cell transformation but had no effect on EGF-induced transformation. AA treatment had no effect on either TPA- or EGF-induced AP-1 transactivation or transformation, but did abrogate the inhibitory effects of DHA on TPA- or EGF-induced AP-1 transactivation and cell transformation in a dose-dependent manner. The results of this study demonstrate that the inhibitory effects of ω3 fatty acids on tumorigenesis are more significant for DHA than for EPA and are related to an inhibition of AP-1. Similarly, because AA abrogates the beneficial effects of DHA, the dietary ratio of ω6 to ω3 fatty acids may be a significant factor in mediating tumor development. PMID:11416221

  13. Mast Cells Infiltrating Inflamed or Transformed Gut Alternatively Sustain Mucosal Healing or Tumor Growth.

    PubMed

    Rigoni, Alice; Bongiovanni, Lucia; Burocchi, Alessia; Sangaletti, Sabina; Danelli, Luca; Guarnotta, Carla; Lewis, Amy; Rizzo, Aroldo; Silver, Andrew R; Tripodo, Claudio; Colombo, Mario P

    2015-09-15

    Mast cells (MC) are immune cells located next to the intestinal epithelium with regulatory function in maintaining the homeostasis of the mucosal barrier. We have investigated MC activities in colon inflammation and cancer in mice either wild-type (WT) or MC-deficient (Kit(W-sh)) reconstituted or not with bone marrow-derived MCs. Colitis was chemically induced with dextran sodium sulfate (DSS). Tumors were induced by administering azoxymethane (AOM) intraperitoneally before DSS. Following DSS withdrawal, Kit(W-sh) mice showed reduced weight gain and impaired tissue repair compared with their WT littermates or Kit(W-sh) mice reconstituted with bone marrow-derived MCs. MCs were localized in areas of mucosal healing rather than damaged areas where they degraded IL33, an alarmin released by epithelial cells during tissue damage. Kit(W-sh) mice reconstituted with MC deficient for mouse mast cell protease 4 did not restore normal mucosal healing or reduce efficiently inflammation after DSS withdrawal. In contrast with MCs recruited during inflammation-associated wound healing, MCs adjacent to transformed epithelial cells acquired a protumorigenic profile. In AOM- and DSS-treated WT mice, high MC density correlated with high-grade carcinomas. In similarly treated Kit(W-sh) mice, tumors were less extended and displayed lower histologic grade. Our results indicate that the interaction of MCs with epithelial cells is dependent on the inflammatory stage, and on the activation of the tissue repair program. Selective targeting of MCs for prevention or treatment of inflammation-associated colon cancer should be timely pondered to allow tissue repair at premalignant stages or to reduce aggressiveness at the tumor stage. PMID:26206557

  14. Critical telomerase activity for uncontrolled cell growth.

    PubMed

    Wesch, Neil L; Burlock, Laura J; Gooding, Robert J

    2016-01-01

    The lengths of the telomere regions of chromosomes in a population of cells are modelled using a chemical master equation formalism, from which the evolution of the average number of cells of each telomere length is extracted. In particular, the role of the telomere-elongating enzyme telomerase on these dynamics is investigated. We show that for biologically relevant rates of cell birth and death, one finds a critical rate, R crit, of telomerase activity such that the total number of cells diverges. Further, R crit is similar in magnitude to the rates of mitosis and cell death. The possible relationship of this result to replicative immortality and its associated hallmark of cancer is discussed. PMID:27500377

  15. Critical telomerase activity for uncontrolled cell growth

    NASA Astrophysics Data System (ADS)

    Wesch, Neil L.; Burlock, Laura J.; Gooding, Robert J.

    2016-08-01

    The lengths of the telomere regions of chromosomes in a population of cells are modelled using a chemical master equation formalism, from which the evolution of the average number of cells of each telomere length is extracted. In particular, the role of the telomere-elongating enzyme telomerase on these dynamics is investigated. We show that for biologically relevant rates of cell birth and death, one finds a critical rate, R crit, of telomerase activity such that the total number of cells diverges. Further, R crit is similar in magnitude to the rates of mitosis and cell death. The possible relationship of this result to replicative immortality and its associated hallmark of cancer is discussed.

  16. Insect growth regulatory activity of Blechnum chilense.

    PubMed

    Hincapié, Carlos A; Monsalve, Zulma; Parada, Katherine; Lamilla, Claudio; Alarcón, Julio; Céspedes, Carlos L; Seigler, David

    2011-08-01

    The genus Blechnum has 13 species that are common plants, well-distributed in Chile. Here, we report a phytochemical analysis of B. chilense (Kaulf.) Mett., as well as the insecticidal effects of extracts of this plant. From the n-hexane fraction four phytoecdysones were isolated: ecdysone, ponasterone, shidasterone and 2-deoxycrustecdysone. A bioassay with Drosophila melanogaster larvae was used to evaluate insecticidal activity. The EtOAc and n-hexane fractions at 800 ppm caused 66.7 and 50.0% larval mortality, respectively. Treatments with both extracts at 800 ppm caused the greatest larval mortality, whereas treatments with 500 and 200 ppm induced premature pupation compared with the control and the highest adult mortality, probably due to interference with ecdysteroid metabolism and inhibition of ecdysis triggering hormone (ETH). The dead adult flies exhibited malformations. PMID:21922904

  17. Insulin-like synergistic stimulation of DNA synthesis in Swiss 3T3 cells by the BSC-1 cell-derived growth inhibitor related to transforming growth factor type beta.

    PubMed Central

    Brown, K D; Holley, R W

    1987-01-01

    A cell growth inhibitor (GI), purified from BSC-1 cell-conditioned medium, has little if any effect on DNA synthesis when added alone to monolayer cultures of quiescent Swiss mouse 3T3 cells in serum-free medium. However, the inhibitor, which is closely related to transforming growth factor type beta (TGF-beta), exhibits a pronounced synergistic stimulation of DNA synthesis in combination with certain peptide (bombesin, vasopressin) or polypeptide (platelet-derived growth factor) mitogens. A similar synergistic response has been demonstrated for TGF-beta purified from human platelets. In the presence of 3 nM bombesin, a half-maximal stimulation of DNA synthesis was obtained at a GI concentration of approximately 60 pg/ml, with a maximal response at approximately 600 pg/ml. The synergistic interactions demonstrated by GI or TGF-beta in stimulating Swiss 3T3 cells closely resemble those previously shown for insulin, and we have observed that GI does not synergize with insulin to stimulate DNA synthesis in these cells. Like insulin, and in contrast to bombesin, vasopressin, and platelet-derived growth factor, GI does not activate cellular inositolphospholipid hydrolysis, calcium mobilization, or cross-regulation of epidermal growth factor receptor affinity. These results raise the possibility that the biochemical pathways activated by GI/TGF-beta and insulin converge at a post-receptor stage. PMID:3295869

  18. Common parietal activation in musical mental transformations across pitch and time.

    PubMed

    Foster, Nicholas E V; Halpern, Andrea R; Zatorre, Robert J

    2013-07-15

    We previously observed that mental manipulation of the pitch level or temporal organization of melodies results in functional activation in the human intraparietal sulcus (IPS), a region also associated with visuospatial transformation and numerical calculation. Two outstanding questions about these musical transformations are whether pitch and time depend on separate or common processing in IPS, and whether IPS recruitment in melodic tasks varies depending upon the degree of transformation required (as it does in mental rotation). In the present study we sought to answer these questions by applying functional magnetic resonance imaging while musicians performed closely matched mental transposition (pitch transformation) and melody reversal (temporal transformation) tasks. A voxel-wise conjunction analysis showed that in individual subjects, both tasks activated overlapping regions in bilateral IPS, suggesting that a common neural substrate subserves both types of mental transformation. Varying the magnitude of mental pitch transposition resulted in variation of IPS BOLD signal in correlation with the musical key-distance of the transposition, but not with the pitch distance, indicating that the cognitive metric relevant for this type of operation is an abstract one, well described by music-theoretic concepts. These findings support a general role for the IPS in systematically transforming auditory stimulus representations in a nonspatial context. PMID:23470983

  19. Thrombospondin-1 Affects Bovine Luteal Function via Transforming Growth Factor-Beta1-Dependent and Independent Actions.

    PubMed

    Farberov, Svetlana; Meidan, Rina

    2016-01-01

    Thrombospondin-1 (THBS1) and transforming growth factor-beta1 (TGFB1) are specifically up-regulated by prostaglandin F2alpha in mature corpus luteum (CL). This study examined the relationship between the expression of THBS1 and TGFB1 and the underlying mechanisms of their actions in luteal endothelial cells (ECs). TGFB1 stimulated SMAD2 phosphorylation and SERPINE1 levels in dose- and time-dependent manners in luteal EC. THBS1 also elevated SERPINE1; this effect was abolished by TGFB1 receptor-1 kinase inhibitor (SB431542). The findings here further imply that THBS1 activates TGFB1 in luteal ECs: THBS1 increased the effects of latent TGFB1 on phosphorylated SMAD (phospho-SMAD) 2 and SERPINE1. THBS1 silencing significantly decreased SERPINE1 and levels of phospho-SMAD2. Lastly, THBS1 actions on SERPINE1 were inhibited by LSKL peptide (TGFB1 activation inhibitor); LSKL also counteracted latent TGFB1-induced phospho-SMAD2. We found that TGFB1 up-regulated its own mRNA levels and those of THBS1. Both compounds generated apoptosis, but THBS1 was significantly more effective (2.5-fold). Notably, this effect of THBS1 was not mediated by TGFB1. THBS1 and TGFB1 also differed in their activation of p38 mitogen-activated protein kinase. Whereas TGFB1 rapidly induced phospho-p38, THBS1 had a delayed effect. Inhibition of p38 pathway by SB203580 did not modulate TGFB1 effect on cell viability, but it amplified THBS1 actions. THBS1-stimulated caspase-3 activation coincided with p38 phosphorylation, suggesting that caspase-induced DNA damage initiated p38 phosphorylation. The in vitro data suggest that a feed-forward loop exists between THBS1, TGFB1, and SERPINE1. Indeed all these three genes were similarly induced in the regressing CL. Their gene products can promote vascular instability, apoptosis, and matrix remodeling during luteolysis. PMID:26658711

  20. Induction of Transforming Growth Factor Beta Receptors following Focal Ischemia in the Rat Brain

    PubMed Central

    Pál, Gabriella; Lovas, Gábor; Dobolyi, Arpád

    2014-01-01

    Transforming growth factor-βs (TGF-βs) regulate cellular proliferation, differentiation, and survival. TGF-βs bind to type I (TGF-βRI) and II receptors (TGF-βRII), which are transmembrane kinase receptors, and an accessory type III receptor (TGF-βRIII). TGF-β may utilize another type I receptor, activin-like kinase receptor (Alk1). TGF-β is neuroprotective in the middle cerebral artery occlusion (MCAO) model of stroke. Recently, we reported the expression pattern of TGF-β1-3 after MCAO. To establish how TGF-βs exert their actions following MCAO, the present study describes the induction of TGF-βRI, RII, RIII and Alk1 at 24 h, 72 h and 1 mo after transient 1 h MCAO as well as following 24 h permanent MCAO using in situ hybridization histochemistry. In intact brain, only TGF-βRI had significant expression: neurons in cortical layer IV contained TGF-βRI. At 24 h after the occlusion, no TGF-β receptors showed induction. At 72 h following MCAO, all four types of TGF-β receptors were induced in the infarct area, while TGF-βRI and RII also appeared in the penumbra. Most cells with elevated TGF-βRI mRNA levels were microglia. TGF-βRII co-localized with both microglial and endothelial markers while TGF-βRIII and Alk1 were present predominantly in endothels. All four TGF-β receptors were induced within the lesion 1 mo after the occlusion. In particular, TGF-βRIII was further induced as compared to 72 h after MCAO. At this time point, TGF-βRIII signal was predominantly not associated with blood vessels suggesting its microglial location. These data suggest that TGF-β receptors are induced after MCAO in a timely and spatially regulated fashion. TGF-β receptor expression is preceded by increased TGF-β expression. TGF-βRI and RII are likely to be co-expressed in microglial cells while Alk1, TGF-βRII, and RIII in endothels within the infarct where TGF-β1 may be their ligand. At later time points, TGF-βRIII may also appear in glial cells to potentially

  1. Angiotensin II stimulated expression of transforming growth factor-beta1 in cardiac fibroblasts and myofibroblasts.

    PubMed

    Campbell, S E; Katwa, L C

    1997-07-01

    Angiotensin II (Ang II) stimulates pathologic myocardial fibrosis. Cardiac fibroblasts (CFb) and myofibroblasts mediate this response, perhaps in part by indirect production of specific cytokines. We sought to determine if Ang II could stimulate transforming growth factor-beta1 (TGF-beta1) gene expression and protein production in adult rat CFb and two cardiac myofibroblast cell types, scar myofibroblasts (MyoFb) and valvular interstitial cells (VIC). Confluent CFb, MyoFb, and VIC in serum-deprived (0.4% FCS) media were treated with Ang II (10(-7) m for CFb; 10(-9) m for MyoFb, VIC) for 24 h. Untreated cells served as controls. Culture media was collected and TGF-beta1 levels determined in triplicate using a sandwich ELISA. Reverse transcriptase-polymerase chain reaction (RT-PCR) analysis was performed to determine TGF-beta1 mRNA expression. Ang II increased CFb (P<0.02) and VIC (P<0.04) TGF-beta1 mRNA expression, while the increase in MyoFb was not statistically significant. MyoFb produced the highest TGF-beta1 levels under control conditions compared to VIC and CFb. Ang II stimulated further TGF-beta1 secretion in VIC and CFb, but not MyoFb. The AT1 receptor antagonist Losartan (10(-7) m) greatly attenuated Ang II-stimulated TGF-B1 secretion and decreased TGF-beta1 immunostaining in VIC. The AT2 receptor antagonist PD123177 (10(-7) m) also decreased secretion and immunostaining of TGF-beta1 in VIC, but to a lesser extent than Losartan. TGF-beta1 secretion by MyoFb was unaffected by Losartan and PD123177, although TGF-B1 immunostaining was absent or greatly decreased, respectively, compared to Ang II-treated MyoFb. Ang II stimulates TGF-beta1 gene expression and/or protein production in cardiac fibroblast-like cells which may act as an autocrine/paracrine stimulus to collagen formation. Furthermore, TGF-beta1 production and secretion in these cells can be modulated by specific Ang II receptor antagonists, suggesting a potential benefit in preventing

  2. Expression of transforming growth factors beta-1, beta 2 and beta 3 in human bladder carcinomas.

    PubMed Central

    Eder, I. E.; Stenzl, A.; Hobisch, A.; Cronauer, M. V.; Bartsch, G.; Klocker, H.

    1997-01-01

    We previously detected elevated transforming growth factor beta-1 (TGF-beta1) serum levels in patients with invasive bladder carcinomas. In this study, we therefore investigated whether elevated serum levels correlate with enhanced TGF-beta expression in human bladder tumours. mRNA levels of TGF-beta1, -beta2 and -beta3 were reduced in bladder tumour tissue to 86%, 68% and 56%, respectively, of the levels in normal urothelium. On the other hand, TGF-beta1 protein levels were found to be higher in superficial tumours (Ta-T1) (mean level of 0.153 ng mg(-1)) and in invasive T2/T3 tumours (mean level of 0.104 ng mg(-1)) compared with normal urothelium (mean level of 0.065 ng mg(-1)). Invasive T4 tumours, however, contained only low amounts of TGF-beta1 (mean level of 0.02 ng mg(-1)). Neither in mean nor in individual patients were serum and tissue TGF-beta levels correlated with each other. Cell culture experiments on primary bladder cells revealed a 57% decrease in TGF-beta1 mRNA levels in tumour compared with normal epithelial cells. Tumour epithelial cells contained about two times higher levels of TGF-beta2 and TGF-beta3 mRNA than normal epithelial cells. Fibroblasts expressed about the same amount of TGF-beta1 or TGF-beta2 as epithelial cells. Yet, fibroblasts released only 19% and 13% of the amount secreted by tumour epithelial cells into the supernatant. TGF-beta3, on the other hand, was expressed by fibroblasts with higher levels than by epithelial cells. TGF-beta1 was the predominent isoform in bladder tissue and cells at protein as well as on mRNA levels indicating that TGFs-beta2 and -beta3 are of minor importance in bladder cancer. In summary, there is a lack of correlation between TGF-beta serum levels and TGF-beta expression in tumour tissue in bladder cancer. Images Figure 1 PMID:9192977

  3. Using Arts-Based Activities to Foster Transformative Learning during a Teaching Practicum in Kenya

    ERIC Educational Resources Information Center

    Black, Glenda; Bernardes, Rogerio

    2012-01-01

    This essay explores and presents strategies we, as Canadian faculty facilitators of a teaching practicum in Kenya, used to foster the pre-service teachers' knowledge and understanding of critical reflection and transformative learning processes by using arts-based activities. Participation in the arts-based activities while in Kenya encouraged the…

  4. Effect of intestinal ischemia-reperfusion on expressions of endogenous basic fibroblast growth factor and transforming growth factor betain lung and its relation with lung repair.

    PubMed

    Fu, Xiao-Bing; Yang, Yin-Hui; Sun, Tong-Zhu; Gu, Xiao-Man; Jiang, Li-Xian; Sun, Xiao-Qing; Sheng, Zhi-Yong

    2000-06-01

    AIM:To study the changes of endogenous transforming growth factor beta(TGFbeta) and basic fibroblast growth factor (bFGF) in lung following intestinal ischemia and reperfusion injury and their effects on lung injury and repair.METHODS:Sixty Wistar rats were divided into five grou