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Sample records for activator upa overexpression

  1. Overexpression of SlUPA-like induces cell enlargement, aberrant development and low stress tolerance through phytohormonal pathway in tomato.

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    Cui, Baolu; Hu, Zongli; Hu, Jingtao; Zhang, Yanjie; Yin, Wencheng; Zhu, Zhiguo; Feng, Ye; Chen, Guoping

    2016-03-30

    upa20 induces cell enlargement and hypertrophy development. In our research, overexpression of SlUPA-like, orthologous to upa20, severely affected the growth of vegetative and reproductive tissues. Wilted leaves curled upwardly and sterile flowers were found in transgenic lines. Through anatomical analysis, palisade and spongy tissues showed fluffy and hypertrophic development in transgenic plants. Gene expression analysis showed that GA responsive, biosynthetic and signal transduction genes (e.g. GAST1, SlGA20OXs, SlGA3OXs, SlGID1s, and SlPREs) were significantly upregulated, indicating that GA response is stimulated by overproduction of SlUPA-like. Furthermore, SlUPA-like was strongly induced by exogenous JA and wounding. Decreased expression of PI-I and induced expression of SlJAZs (including SlJAZ2, SlJAZ10 and SlJAZ11) were observed in transgenic plants, suggesting that JA response is repressed. In addition, SlUPA-like overexpressed plant exhibited more opened stoma and higher water loss than the control when treated with dehydration stress, which was related to decreased ABA biosynthesis, signal transduction and response. Particularly, abnormal developments of transgenic plants promote the plant susceptibility to Xanthomonas campestris pv. campestris. Therefore, it is deduced from these results that SlUPA-like plays vital role in regulation of plant development and stress tolerance through GA, JA and ABA pathways.

  2. Comparison of the inhibition of urokinase-type plasminogen activator (u-PA) activity by monoclonal antibodies specific for u-PA as assessed by different assays

    NARCIS (Netherlands)

    Boheemen, P.A. van; Hoogen, N.M. van den; Koolwijk, N.

    1995-01-01

    Six murine monoclonal antibodies (MAbs) specific for urokinase-type plasminogen activator (u-PA) were tested for their ability to inhibit u-PA activity in three different assays with respect to amidolytic activity, plasminogen activation and fibrinolytic activity. Two of the MAbs were able to inhibi

  3. Poised transcription factories prime silent uPA gene prior to activation.

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    Carmelo Ferrai

    2010-01-01

    Full Text Available The position of genes in the interphase nucleus and their association with functional landmarks correlate with active and/or silent states of expression. Gene activation can induce chromatin looping from chromosome territories (CTs and is thought to require de novo association with transcription factories. We identify two types of factory: "poised transcription factories," containing RNA polymerase II phosphorylated on Ser5, but not Ser2, residues, which differ from "active factories" associated with phosphorylation on both residues. Using the urokinase-type plasminogen activator (uPA gene as a model system, we find that this inducible gene is predominantly associated with poised (S5p(+S2p(- factories prior to activation and localized at the CT interior. Shortly after induction, the uPA locus is found associated with active (S5p(+S2p(+ factories and loops out from its CT. However, the levels of gene association with poised or active transcription factories, before and after activation, are independent of locus positioning relative to its CT. RNA-FISH analyses show that, after activation, the uPA gene is transcribed with the same frequency at each CT position. Unexpectedly, prior to activation, the uPA loci internal to the CT are seldom transcriptionally active, while the smaller number of uPA loci found outside their CT are transcribed as frequently as after induction. The association of inducible genes with poised transcription factories prior to activation is likely to contribute to the rapid and robust induction of gene expression in response to external stimuli, whereas gene positioning at the CT interior may be important to reinforce silencing mechanisms prior to induction.

  4. Plasminogen activator inhibitor-1 (PAI-1 and urokinase plasminogen activator (uPA in sputum of allergic asthma patients.

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    Sebastian Zukowski

    2008-06-01

    Full Text Available Urokinase plasminogen activator (uPA and its inhibitor (PAI-1 have been associated with asthma. The aim of this study was to evaluate concentration of uPA and PAI-1 in induced sputum of house dust mite allergic asthmatics (HDM-AAs. The study was performed on 19 HDM-AAs and 8 healthy nonatopic controls (HCs. Concentration of uPA and PAI-1 was evaluated in induced sputum supernatants using ELISA method. In HDM-AAs the median sputum concentration of uPA (128 pg/ml; 95% CI 99 to 183 pg/ml and PAI-1 (4063 pg/ml; 95%CI 3319 to 4784 pg/ml were significantly greater than in HCs (17 pg/ml; 95%CI 12 to 32 pg/ml; p<0.001 and 626 pg/ml; 95%CI 357 to 961 pg/ml; p<0.001 for uPA and PAI-1 respectively. The sputum concentration of uPA correlated with sputum total cell count (r=0.781; p=0.0001 and with logarithmically transformed exhaled nitric oxide concentration (eNO (r=0.486; p=0.035 but not with FEV1 or bronchial reactivity to histamine. On the contrary, the sputum PAI-1 concentration correlated with FEV1 (r=-0,718; p=0.0005 and bronchial reactivity to histamine expressed as log(PC20 (r=-0.824; p<0.0001 but did not correlate with sputum total cell count or eNO. The results of this study support previous observations linking PAI-1 with airway remodeling and uPA with cellular inflammation. Moreover, the observed effect of uPA seems to be independent of its fibrynolytic activity.

  5. Overexpression of MMP-3 and uPA with Diminished PAI-1 Related to Metastasis in Ductal Breast Cancer Patients Attending a Public Hospital in Mexico City

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    Luis Miguel Barajas-Castañeda

    2016-01-01

    Full Text Available Extracellular matrix metalloproteases and the fibrinolytic system are important protease systems interacting with each other in charge of remodeling and recycling of tissues. Their role in tumor invasion and metastasis is often discussed. In this study several metalloproteases such as MMP-1, MMP-3, MMP-9, and TIMP-1 together with molecules from the fibrinolytic system like uPA, its receptor uPAR, and its inhibitor, PAI-1, were studied by immune-histochemistry to establish a comparison with and without metastasis. From the (118 primary tumors of Mexican patients with ductal breast cancer studied, 56% were grade II and 69% were size T2; the group with metastatic ganglia included 64 samples (54.3%. In patients with metastasis the estimated expression of MMP-3 and uPA (resp., 28% and 45% was higher than that from no metastatic tumors; it means there is higher expression of both markers in metastatic tumors (p<0.05. At the same time, metastatic tumors showed statistically significant lower signal of PAI-1 (24% than tumors without metastasis (p<0.05. We concluded that overexpression of MMP-3 and uPA, altogether with diminished expression of PAI-1 from metastatic tumors, might be a crucial step towards metastasis in ductal breast cancer. Nevertheless, additional studies in different populations are necessary to establish a pattern.

  6. Overexpression of MMP-3 and uPA with Diminished PAI-1 Related to Metastasis in Ductal Breast Cancer Patients Attending a Public Hospital in Mexico City

    Science.gov (United States)

    Barajas-Castañeda, Luis Miguel; Cortés-Gutiérrez, Evelin; García-Rodríguez, Francisco Mario; Campos-Rodríguez, Rafael; Lara-Padilla, Eleazar; Enríquez-Rincón, Fernando; Figueroa-Arredondo, Paula

    2016-01-01

    Extracellular matrix metalloproteases and the fibrinolytic system are important protease systems interacting with each other in charge of remodeling and recycling of tissues. Their role in tumor invasion and metastasis is often discussed. In this study several metalloproteases such as MMP-1, MMP-3, MMP-9, and TIMP-1 together with molecules from the fibrinolytic system like uPA, its receptor uPAR, and its inhibitor, PAI-1, were studied by immune-histochemistry to establish a comparison with and without metastasis. From the (118) primary tumors of Mexican patients with ductal breast cancer studied, 56% were grade II and 69% were size T2; the group with metastatic ganglia included 64 samples (54.3%). In patients with metastasis the estimated expression of MMP-3 and uPA (resp., 28% and 45%) was higher than that from no metastatic tumors; it means there is higher expression of both markers in metastatic tumors (p < 0.05). At the same time, metastatic tumors showed statistically significant lower signal of PAI-1 (24%) than tumors without metastasis (p < 0.05). We concluded that overexpression of MMP-3 and uPA, altogether with diminished expression of PAI-1 from metastatic tumors, might be a crucial step towards metastasis in ductal breast cancer. Nevertheless, additional studies in different populations are necessary to establish a pattern. PMID:27975070

  7. Expression of the urokinase plasminogen activator receptor (uPAR) and its ligand (uPA) in brain tissues of human immunodeficiency virus patients with opportunistic cerebral diseases.

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    Nebuloni, Manuela; Cinque, Paola; Sidenius, Nicolai; Ferri, Angelita; Lauri, Eleonora; Omodeo-Zorini, Elisabetta; Zerbi, Pietro; Vago, Luca

    2009-01-01

    The urokinase plasminogen activator receptor (uPAR) and its ligand (uPA) play an important role in cell migration and extracellular proteolysis. We previously described uPAR/uPA overexpression in the cerebrospinal fluid (CSF) and brain tissues of patients with human immunodeficiency virus (HIV)-related cerebral diseases. In this study, we examined uPAR/uPA expression by immunohistochemistry (IHC) in brains of HIV patients with opportunistic cerebral lesions and in HIV-positive/negative controls. uPAR was found in macrophages/microglia with the highest levels in cytomegalovirus (CMV) encephalitis, toxoplasmosis, and lymphomas; in cryptococcosis and progressive multifocal leukoencephalopathy (PML) cases, only a few positive cells were found and no positivity was observed in controls. uPA expression was demonstrated only in a few macrophages/microglia and lymphocytes in all the cases and HIV-positive controls without different pattern of distribution; no uPA immunostaining was found in cryptococcosis and HIV-negative controls. The higher expression of uPAR/uPA in most of the opportunistic cerebral lesions supports their role in these diseases, suggesting their contribution to tissue injury.

  8. Urokinase plasminogen activator (uPA and plasminogen activator inhibitor type-1 (PAI-1 in breast cancer - correlation with traditional prognostic factors

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    Lampelj Maja

    2015-12-01

    Full Text Available Background. Urokinase plasminogen activator (uPA and plasminogen activator inhibitor type-1 (PAI-1 play a key role in tumour invasion and metastasis. High levels of both proteolytic enzymes are associated with poor prognosis in breast cancer patients. The purpose of this study was to evaluate the correlation between traditional prognostic factors and uPA and PAI-1 expression in primary tumour of breast cancer patients.

  9. Signalling networks associated with urokinase-type plasminogen activator (uPA) and its inhibitor PAI-1 in breast cancer tissues: new insights from protein microarray analysis.

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    Wolff, Claudia; Malinowsky, Katharina; Berg, Daniela; Schragner, Kerstin; Schuster, Tibor; Walch, Axel; Bronger, Holger; Höfler, Heinz; Becker, Karl-Friedrich

    2011-01-01

    The urokinase-type plasminogen activator (uPA) and the main uPA inhibitor PAI-1 play important roles in cell migration and invasion in both physiological and pathological contexts. Both factors are clinically applicable predictive markers in node-negative breast cancer patients that are used to stratify patients for adjuvant chemotherapy. In addition to their classical functions in plasmin regulation, both factors are key components in cancer-related cell signalling. Such signalling cascades are well described in cell culture systems, but a better understanding of uPA- and PAI-1-associated signalling networks in clinical tissues is needed. We examined the expression of uPA, PAI-1, and 21 signalling molecules in 201 primary breast cancer tissues using protein microarrays. Expression of uPA was significantly correlated with the expression of ERK and Stat3, while expression of PAI-1 was correlated with the uPA receptor and Akt activation, presumably via integrin and HER-receptor signalling. Analysis of uPA expression did not reveal any significant correlation with staging, grading or age of the patients. The PAI-1 expression was correlated with nodal stage. Network monitoring for uPA and PAI-1 in breast cancer reveals interactions with main signalling cascades and extends the findings from cell culture experiments. Our results reveal possible mechanisms underlying cancer development.

  10. A key role for the urokinase plasminogen activator (uPA) in invasive Group A streptococcal infection.

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    Sanderson-Smith, Martina L; Zhang, Yueling; Ly, Diane; Donahue, Deborah; Hollands, Andrew; Nizet, Victor; Ranson, Marie; Ploplis, Victoria A; Walker, Mark J; Castellino, Francis J

    2013-01-01

    Recruitment of the serine protease plasmin is central to the pathogenesis of many bacterial species, including Group A streptococcus (GAS), a leading cause of morbidity and mortality globally. A key process in invasive GAS disease is the ability to accumulate plasmin at the cell surface, however the role of host activators of plasminogen in this process is poorly understood. Here, we demonstrate for the first time that the urokinase-type plasminogen activator (uPA) contributes to plasmin recruitment and subsequent invasive disease initiation in vivo. In the absence of a source of host plasminogen activators, streptokinase (Ska) was required to facilitate cell surface plasmin acquisition by GAS. However, in the absence of Ska, host activators were sufficient to promote cell surface plasmin acquisition by GAS strain 5448 during incubation with plasminogen or human plasma. Furthermore, GAS were able mediate a significant increase in the activation of zymogen pro-uPA in human plasma. In order to assess the contribution of uPA to invasive GAS disease, a previously undescribed transgenic mouse model of infection was employed. Both C57/black 6J, and AlbPLG1 mice expressing the human plasminogen transgene, were significantly more susceptible to invasive GAS disease than uPA-/- mice. The observed decrease in virulence in uPA-/-mice was found to correlate directly with a decrease in bacterial dissemination and reduced cell surface plasmin accumulation by GAS. These findings have significant implications for our understanding of GAS pathogenesis, and research aimed at therapeutic targeting of plasminogen activation in invasive bacterial infections.

  11. A key role for the urokinase plasminogen activator (uPA in invasive Group A streptococcal infection.

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    Martina L Sanderson-Smith

    Full Text Available Recruitment of the serine protease plasmin is central to the pathogenesis of many bacterial species, including Group A streptococcus (GAS, a leading cause of morbidity and mortality globally. A key process in invasive GAS disease is the ability to accumulate plasmin at the cell surface, however the role of host activators of plasminogen in this process is poorly understood. Here, we demonstrate for the first time that the urokinase-type plasminogen activator (uPA contributes to plasmin recruitment and subsequent invasive disease initiation in vivo. In the absence of a source of host plasminogen activators, streptokinase (Ska was required to facilitate cell surface plasmin acquisition by GAS. However, in the absence of Ska, host activators were sufficient to promote cell surface plasmin acquisition by GAS strain 5448 during incubation with plasminogen or human plasma. Furthermore, GAS were able mediate a significant increase in the activation of zymogen pro-uPA in human plasma. In order to assess the contribution of uPA to invasive GAS disease, a previously undescribed transgenic mouse model of infection was employed. Both C57/black 6J, and AlbPLG1 mice expressing the human plasminogen transgene, were significantly more susceptible to invasive GAS disease than uPA-/- mice. The observed decrease in virulence in uPA-/-mice was found to correlate directly with a decrease in bacterial dissemination and reduced cell surface plasmin accumulation by GAS. These findings have significant implications for our understanding of GAS pathogenesis, and research aimed at therapeutic targeting of plasminogen activation in invasive bacterial infections.

  12. Progression of Osteosarcoma from a Non-Metastatic to a Metastatic Phenotype Is Causally Associated with Activation of an Autocrine and Paracrine uPA Axis.

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    Liliana Endo-Munoz

    Full Text Available Pulmonary metastasis is the major untreatable complication of osteosarcoma (OS resulting in 10-20% long-term survival. The factors and pathways regulating these processes remain unclear, yet their identification is crucial in order to find new therapeutic targets. In this study we used a multi-omics approach to identify molecules in metastatic and non-metastatic OS cells that may contribute to OS metastasis, followed by validation in vitro and in vivo. We found elevated levels of the urokinase plasminogen activator (uPA and of the uPA receptor (uPAR exclusively in metastatic OS cells. uPA was secreted in soluble form and as part of the protein cargo of OS-secreted extracellular vesicles, including exosomes. In addition, in the tumour microenvironment, uPA was expressed and secreted by bone marrow cells (BMC, and OS- and BMC-derived uPA significantly and specifically stimulated migration of metastatic OS cells via uPA-dependent signaling pathways. Silencing of uPAR in metastatic OS cells abrogated the migratory response to uPA in vitro and decreased metastasis in vivo. Finally, a novel small-molecule inhibitor of uPA significantly (P = 0.0004 inhibited metastasis in an orthotopic mouse model of OS. Thus, we show for the first time that malignant conversion of OS cells to a metastatic phenotype is defined by activation of the uPA/uPAR axis in both an autocrine and paracrine fashion. Furthermore, metastasis is driven by changes in OS cells as well as in the microenvironment. Finally, our data show that pharmacological inhibition of the uPA/uPAR axis with a novel small-molecule inhibitor can prevent the emergence of metastatic foci.

  13. Plasminogen activation independent of uPA and tPA maintains wound healing in gene-deficient mice

    DEFF Research Database (Denmark)

    Lund, Leif R; Green, Kirsty A; Stoop, Allart A;

    2006-01-01

    Simultaneous ablation of the two known activators of plasminogen (Plg), urokinase-type (uPA) and the tissue-type (tPA), results in a substantial delay in skin wound healing. However, wound closure and epidermal re-epithelialization are significantly less impaired in uPA;tPA double-deficient mice...... than in Plg-deficient mice. Skin wounds in uPA;tPA-deficient mice treated with the broad-spectrum matrix metalloproteinase (MMP) inhibitor galardin (N-[(2R)-2-(hydroxamido-carbonylmethyl)-4-methylpentanoyl]-L-tryptophan methylamide) eventually heal, whereas skin wounds in galardin-treated Plg......-deficient mice do not heal. Furthermore, plasmin is biochemically detectable in wound extracts from uPA;tPA double-deficient mice. In vivo administration of a plasma kallikrein (pKal)-selective form of the serine protease inhibitor ecotin exacerbates the healing impairment of uPA;tPA double-deficient wounds...

  14. Urinary-type plasminogen activator (uPA) and its receptor (uPAR) in squamous cell carcinoma of the oral cavity.

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    Shi, Zonggao; Stack, M Sharon

    2007-10-15

    OSCC (oral squamous cell carcinoma) is the most common oral malignancy and is estimated to affect approx. 350000 new patients worldwide this year. OSCC is characterized by a high degree of morbidity and mortality, as most patients exhibit local, regional and distant metastasis at the time of diagnosis. Recent genome-wide screening efforts have identified the serine proteinase uPA (urinary-type plasminogen activator, also known as urokinase) as a strong biomarker for prediction of poor disease outcome and a key candidate for molecular classification of oral neoplasms using a 'gene signature' approach. The proteinase uPA binds a surface-anchored receptor designated uPAR (uPA receptor), focalizing proteolytic activity to the pericellular milieu. Furthermore, uPA-uPAR can interact with transmembrane proteins to modify multiple signal transduction pathways and influence a wide variety of cellular behaviours. Correlative clinical data show elevated uPA-uPAR in oral tumour tissues, with tumours exhibiting high levels of both uPA and uPAR as the most invasive. Combined in vitro, pre-clinical and clinical data support the need for further analysis of uPA-uPAR as a prognostic indicator as well as a potential therapeutic target in OSCC.

  15. Regulation of cell migration and invasion by specific modules of uPA: mechanistic insights and specific inhibitors.

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    Carriero, Maria Vincenza; Franco, Paola; Votta, Giuseppina; Longanesi-Cattani, Immacolata; Vento, Maria Teresa; Masucci, Maria Teresa; Mancini, Alessandro; Caputi, Mario; Iaccarino, Ingram; Stoppelli, Maria Patrizia

    2011-11-01

    Urokinase (uPA) is a 411 residues serine protease originally identified for its ability to activate plasminogen and generate plasmin, a broad-spectrum matrix- and fibrin-degrading enzyme. Later, this protease has been shown to possess also a clear-cut ability to stimulate cell migration and survival in a catalytic-independent manner. This activity turned out to be exerted through the growth factor-like domain (GFD-like, residues 1-49) of the protease binding to a GPIanchored membrane receptor (uPAR), in complex with transmembrane receptors such as integrins, the epidermal growth factor and the formyl-peptide receptors. Direct binding of uPA to integrins through its kringle (residues 50-131) and connecting peptide (residues 132-158) regions results in enhanced migration. The dual function of uPA in promoting migration while reducing the physical resistance of extracellular matrix underlies its crucial role in the invasion of malignant tumours. Consolidated evidence emerging from animal models and clinical studies shows that the overexpression of uPA is a causal determinant to tumour metastasis and is associated to a poor prognosis. Therefore, pinpointing the molecular interactions and identifying novel agents to interfere with the diverse activities of uPA is a goal of basic and applied research. In this review, we discuss the general theme of cell migration and invasion. A description of the uPA structure-function relationship and the functional effects of isolated domains is presented. Current information on molecular agonistic as well as antagonistic compounds, including the compounds which have reached clinical trials, is provided.

  16. Concomitant lack of MMP9 and uPA disturbs physiological tissue remodeling

    DEFF Research Database (Denmark)

    Lund, Ida K; Nielsen, Boye S; Almholt, Kasper

    2011-01-01

    Urokinase-type plasminogen activator (uPA) and matrix metalloproteinase-9 (MMP9, gelatinase B) have separately been recognized to play important roles in various tissue remodeling processes. In this study, we demonstrate that deficiency for MMP9 in combination with ablation of either uPA- or tissue...

  17. A combination of desmopressin and docetaxel inhibit cell proliferation and invasion mediated by urokinase-type plasminogen activator (uPA) in human prostate cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Sasaki, Hiroshi; Klotz, Laurence H. [Division of Urology, Sunnybrook Health Sciences Center, Toronto, ON (Canada); Sugar, Linda M. [Department of Pathology, Sunnybrook Health Sciences Center, Toronto, ON (Canada); Kiss, Alexander [Department of Research Design and Biostatistics, Institute for Clinical Evaluative Sciences, Sunnybrook Health Sciences Center, Toronto, ON (Canada); Venkateswaran, Vasundara, E-mail: vasundara.venkateswaran@sunnybrook.ca [Division of Urology, Sunnybrook Health Sciences Center, Toronto, ON (Canada)

    2015-08-28

    Background: This study was designed to assess the effectiveness of a combination treatment using both desmopressin and docetaxel in prostate cancer treatment. Desmopressin is a well-known synthetic analogue of the antidiuretic hormone vasopressin. It has recently been demonstrated to inhibit tumor progression and metastasis in in vivo models. Docetaxel is widely used for the treatment of castration resistant prostate cancer (CRPC) patients. However, durable responses have been uncommon to date. In this study, we investigated the anti-tumor effect of desmopressin in combination with docetaxel in vitro and in vivo. Methods: Two prostate cancer cells (PC3, LNCaP) were treated with different concentrations of desmopressin alone, docetaxel alone, and a combination of desmopressin and docetaxel. Cell proliferation was determined by MTS assay. The anti-invasive and anti-migration potential of desmopressin and in combination with docetaxel were examined by wound healing assay, migration chamber assay, and matrigel invasion assay. Results: The combination of desmopressin and docetaxel resulted in a significant inhibition of PC3 and LNCaP cell proliferation (p < 0.01). Additionally, cell migration and invasion were also inhibited by the combination when compared to that of either treatment alone in PC3 cells (p < 0.01). The anti-tumor effect of this combination treatment was associated with down-regulation of both urokinase-type plasminogen activator (uPA) and matrix metalloproteinase (MMP-2 and MMP-9) in PC3 cells. Conclusions: We are the first to elucidate the anti-tumor and anti-metastatic potential of desmopressin in combination with docetaxel in a prostate cancer model via the uPA-MMP pathway. Our finding could potentially contribute to the therapeutic profile of desmopressin and enhance the efficacy of docetaxel based treatment for CRPC. - Highlights: • Desmopressin inhibits cell proliferation in prostate cancer cells. • The expression of cyclin A and CDK2

  18. Correlation between Expression of P38 MAPK-Signaling and uPA in Breast Cancer

    Institute of Scientific and Technical Information of China (English)

    Yanchun Han; Luying Liu; Dongxia Yan; Guihua Wang

    2008-01-01

    OBJECTIVE To study the expression of phosphorylated p38 mitogen.Activated protein kinase(p-p38)and uPA and the correlation of their expression with breast cancer Clinic.patholodiCal characteristics,and to investigate the role of the p38MAPK-signaling pathway in regulating uPA expression in breast cancer cells.METHODS Immunohistochemistry(S-P)was used to test the expression of P-p38 and uPA in 60 specimens of breast cancer tissues.Western blots were adopted to detect expression of the p-p38 and uPA proteins in MDA-MB-231 and MCF-7 breast cancer cells.And uPA expression after treatment with SB203580,a specific inhibitor of p38 MAPK.RESULTS The positive rate of the P.P38 protein and uPA protein expression in the breast cancer tissues was 56.7% and 60.0%.Respectively.The expression of P.P38 was positively related to the expression of uPA(r=0.316,P0.05).The expression of p-p38 and uPA in MDA. MB-231 cells was higher than that in MCF.7 cells.SB203580 inhibited the p38 MAPK pathway and reduced uPA protein expression.CONCLUSI0N The p38 MAPK-signaling pathway promotes breast cancer malignant progression by up.Regulating uPA expression,and it may be an important process in breast cancer invasion and metastasis.

  19. Ganodermanontriol (GDNT) exerts its effect on growth and invasiveness of breast cancer cells through the down-regulation of CDC20 and uPA

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Jiahua; Jedinak, Andrej [Cancer Research Laboratory, Methodist Research Institute, Indiana University Health, Indianapolis, IN (United States); Sliva, Daniel, E-mail: dsliva@iuhealth.org [Cancer Research Laboratory, Methodist Research Institute, Indiana University Health, Indianapolis, IN (United States); Department of Medicine, School of Medicine, Indiana University, Indianapolis, IN (United States); Indiana University Simon Cancer Center, School of Medicine, Indiana University, Indianapolis, IN (United States)

    2011-11-18

    Highlights: Black-Right-Pointing-Pointer Ganodermanontriol (GDNT), a Ganoderma mushroom alcohol, inhibits growth of breast cancer cells. Black-Right-Pointing-Pointer CDC20 is over-expressed in tumors but not in the tumor surrounding tissue in breast cancer patients. Black-Right-Pointing-Pointer GDNT inhibits expression of CDC20 in breast cancer cells. Black-Right-Pointing-Pointer GDNT inhibits cell adhesion, cell migration and cell invasion of breast cancer cells. Black-Right-Pointing-Pointer GDNT inhibits secretion of uPA and down-regulates expression of uPAR in breast cancer cells. -- Abstract: Ganoderma lucidum is a medicinal mushroom that has been recognized by Traditional Chinese Medicine (TCM). Although some of the direct anticancer activities are attributed to the presence of triterpenes-ganoderic and lucidenic acids-the activity of other compounds remains elusive. Here we show that ganodermanontriol (GDNT), a Ganoderma alcohol, specifically suppressed proliferation (anchorage-dependent growth) and colony formation (anchorage-independent growth) of highly invasive human breast cancer cells MDA-MB-231. GDNT suppressed expression of the cell cycle regulatory protein CDC20, which is over-expressed in precancerous and breast cancer cells compared to normal mammary epithelial cells. Moreover, we found that CDC20 is over-expressed in tumors when compared to the tissue surrounding the tumor in specimens from breast cancer patients. GDNT also inhibited invasive behavior (cell adhesion, cell migration, and cell invasion) through the suppression of secretion of urokinase-plasminogen activator (uPA) and inhibited expression of uPA receptor. In conclusion, mushroom GDNT is a natural agent that has potential as a therapy for invasive breast cancers.

  20. Modulation of Cellular Migration and Survival by c-Myc through the Downregulation of Urokinase (uPA) and uPA Receptor▿ †

    Science.gov (United States)

    Alfano, Daniela; Votta, Giuseppina; Schulze, Almut; Downward, Julian; Caputi, Mario; Stoppelli, Maria Patrizia; Iaccarino, Ingram

    2010-01-01

    It has been proposed that c-Myc proapoptotic activity accounts for most of its restraint of tumor formation. We established a telomerase-immortalized human epithelial cell line expressing an activatable c-Myc protein. We found that c-Myc activation induces, in addition to increased sensitivity to apoptosis, reductions in cell motility and invasiveness. Transcriptome analysis revealed that urokinase (uPA) and uPA receptor (uPAR) were strongly downregulated by c-Myc. Evidence is provided that the repression of uPA and uPAR may account for most of the antimigratory and proapoptotic activities of c-Myc. c-Myc is known to cooperate with Ras in cellular transformation. We therefore investigated if this cooperation could converge in the control of uPA/uPAR expression. We found that Ras is able to block the effects of c-Myc activation on apoptosis and cellular motility but not on cell invasiveness. Accordingly, the activation of c-Myc in the context of Ras expression had only minor influence on uPAR expression but still had a profound repressive effect on uPA expression. Thus, the differential regulation of uPA and uPAR by c-Myc and Ras correlates with the effects of these two oncoproteins on cell motility, invasiveness, and survival. In conclusion, we have discovered a novel link between c-Myc and uPA/uPAR. We propose that reductions of cell motility and invasiveness could contribute to the inhibition of tumorigenesis by c-Myc and that the regulation of uPA and uPAR expression may be a component of the ability of c-Myc to reduce motility and invasiveness. PMID:20123981

  1. Modulation of cellular migration and survival by c-Myc through the downregulation of urokinase (uPA) and uPA receptor.

    Science.gov (United States)

    Alfano, Daniela; Votta, Giuseppina; Schulze, Almut; Downward, Julian; Caputi, Mario; Stoppelli, Maria Patrizia; Iaccarino, Ingram

    2010-04-01

    It has been proposed that c-Myc proapoptotic activity accounts for most of its restraint of tumor formation. We established a telomerase-immortalized human epithelial cell line expressing an activatable c-Myc protein. We found that c-Myc activation induces, in addition to increased sensitivity to apoptosis, reductions in cell motility and invasiveness. Transcriptome analysis revealed that urokinase (uPA) and uPA receptor (uPAR) were strongly downregulated by c-Myc. Evidence is provided that the repression of uPA and uPAR may account for most of the antimigratory and proapoptotic activities of c-Myc. c-Myc is known to cooperate with Ras in cellular transformation. We therefore investigated if this cooperation could converge in the control of uPA/uPAR expression. We found that Ras is able to block the effects of c-Myc activation on apoptosis and cellular motility but not on cell invasiveness. Accordingly, the activation of c-Myc in the context of Ras expression had only minor influence on uPAR expression but still had a profound repressive effect on uPA expression. Thus, the differential regulation of uPA and uPAR by c-Myc and Ras correlates with the effects of these two oncoproteins on cell motility, invasiveness, and survival. In conclusion, we have discovered a novel link between c-Myc and uPA/uPAR. We propose that reductions of cell motility and invasiveness could contribute to the inhibition of tumorigenesis by c-Myc and that the regulation of uPA and uPAR expression may be a component of the ability of c-Myc to reduce motility and invasiveness.

  2. Cancer therapy trials employing level-of-evidence-1 disease forecast cancer biomarkers uPA and its inhibitor PAI-1

    DEFF Research Database (Denmark)

    Schmitt, Manfred; Harbeck, Nadia; Brünner, Nils;

    2011-01-01

    and III breast cancer therapy trials (Chemo-N0, NNBC-3 and Plan B), and introduces ongoing clinical trials targeting uPA in advanced cancers of the breast and pancreas, employing synthetic small-size drugs to counteract uPA activity (WX-UK1, Mesupron(®)). The therapeutic effect of a uPA-derived small...

  3. uPA and PAI-1-Related Signaling Pathways Differ between Primary Breast Cancers and Lymph Node Metastases12

    Science.gov (United States)

    Malinowsky, Katharina; Wolff, Claudia; Berg, Daniela; Schuster, Tibor; Walch, Axel; Bronger, Holger; Mannsperger, Heiko; Schmidt, Christian; Korf, Ulrike; Höfler, Heinz; Becker, Karl-Friedrich

    2012-01-01

    The supporting role of urokinase-type plasminogen activator (uPA) and its inhibitor plasminogen activator inhibitor 1 (PAI-1) in migration and invasion is well known. In addition, both factors are key components in cancer cell-related signaling. However, little information is available for uPA and PAI-1-associated signaling pathways in primary cancers and corresponding lymph node metastases. The aim of this study was to compare the expression of uPA and PAI-1-associated signaling proteins in 52 primary breast cancers and corresponding metastases. Proteins were extracted from formalin-fixed paraffin-embedded tissue samples of the primary tumors and metastases. Protein lysates were subsequently analyzed by reverse phase protein array for the expression of members of the PI3K/AKT (FAK, GSK3-β, ILK, pGSK3-β, PI3K, and ROCK) and the MAPK pathways (pp38, pSTAT3, and p38). A solid correlation of uPA expression existed between primary tumors and metastases, whereas PAI-1 expression did not significantly correlate between them. The correlations of uPA and PAI-1 with signaling pathways found in primary tumors did not persist in metastases. Analysis of single molecules revealed that some correlated well between tumors and metastases (FAK, pGSK3-β, ILK, Met, PI3K, ROCK, uPA, p38, and pp38), whereas others did not (PAI-1 and GSK3-β). Whether the expression of a protein correlated between tumor and metastasis or not was independent of the pathway the protein is related to. These findings hint at a complete deregulation of uPA and PAI-1-related signaling in metastases, which might be the reason why uPA and PAI-1 reached clinical relevance only for lymph node-negative breast cancer tissues. PMID:22496926

  4. uPA and PAI-1-Related Signaling Pathways Differ between Primary Breast Cancers and Lymph Node Metastases.

    Science.gov (United States)

    Malinowsky, Katharina; Wolff, Claudia; Berg, Daniela; Schuster, Tibor; Walch, Axel; Bronger, Holger; Mannsperger, Heiko; Schmidt, Christian; Korf, Ulrike; Höfler, Heinz; Becker, Karl-Friedrich

    2012-04-01

    The supporting role of urokinase-type plasminogen activator (uPA) and its inhibitor plasminogen activator inhibitor 1 (PAI-1) in migration and invasion is well known. In addition, both factors are key components in cancer cell-related signaling. However, little information is available for uPA and PAI-1-associated signaling pathways in primary cancers and corresponding lymph node metastases. The aim of this study was to compare the expression of uPA and PAI-1-associated signaling proteins in 52 primary breast cancers and corresponding metastases. Proteins were extracted from formalin-fixed paraffin-embedded tissue samples of the primary tumors and metastases. Protein lysates were subsequently analyzed by reverse phase protein array for the expression of members of the PI3K/AKT (FAK, GSK3-β, ILK, pGSK3-β, PI3K, and ROCK) and the MAPK pathways (pp38, pSTAT3, and p38). A solid correlation of uPA expression existed between primary tumors and metastases, whereas PAI-1 expression did not significantly correlate between them. The correlations of uPA and PAI-1 with signaling pathways found in primary tumors did not persist in metastases. Analysis of single molecules revealed that some correlated well between tumors and metastases (FAK, pGSK3-β, ILK, Met, PI3K, ROCK, uPA, p38, and pp38), whereas others did not (PAI-1 and GSK3-β). Whether the expression of a protein correlated between tumor and metastasis or not was independent of the pathway the protein is related to. These findings hint at a complete deregulation of uPA and PAI-1-related signaling in metastases, which might be the reason why uPA and PAI-1 reached clinical relevance only for lymph node-negative breast cancer tissues.

  5. Production of factor VIII by human liver sinusoidal endothelial cells transplanted in immunodeficient uPA mice.

    Directory of Open Access Journals (Sweden)

    Marina E Fomin

    Full Text Available Liver sinusoidal endothelial cells (LSECs form a semi-permeable barrier between parenchymal hepatocytes and the blood. LSECs participate in liver metabolism, clearance of pathological agents, immunological responses, architectural maintenance of the liver and synthesis of growth factors and cytokines. LSECs also play an important role in coagulation through the synthesis of Factor VIII (FVIII. Herein, we phenotypically define human LSECs isolated from fetal liver using flow cytometry and immunofluorescence microscopy. Isolated LSECs were cultured and shown to express endothelial markers and markers specific for the LSEC lineage. LSECs were also shown to engraft the liver when human fetal liver cells were transplanted into immunodeficient mice with liver specific expression of the urokinase-type plasminogen activator (uPA transgene (uPA-NOG mice. Engrafted cells expressed human Factor VIII at levels approaching those found in human plasma. We also demonstrate engraftment of adult LSECs, as well as hepatocytes, transplanted into uPA-NOG mice. We propose that overexpression of uPA provides beneficial conditions for LSEC engraftment due to elevated expression of the angiogenic cytokine, vascular endothelial growth factor. This work provides a detailed characterization of human midgestation LSECs, thereby providing the means for their purification and culture based on their expression of CD14 and CD32 as well as a lack of CD45 expression. The uPA-NOG mouse is shown to be a permissive host for human LSECs and adult hepatocytes, but not fetal hepatoblasts. Thus, these mice provide a useful model system to study these cell types in vivo. Demonstration of human FVIII production by transplanted LSECs encourages further pursuit of LSEC transplantation as a cellular therapy for the treatment of hemophilia A.

  6. Neutralisation of uPA with a monoclonal antibody reduces plasmin formation and delays skin wound healing in tPA-deficient mice

    DEFF Research Database (Denmark)

    Jögi, Annika; Rønø, Birgitte; Lund, Ida K;

    2010-01-01

    Proteolytic degradation by plasmin and metalloproteinases is essential for epidermal regeneration in skin wound healing. Plasminogen deficient mice have severely delayed wound closure as have mice simultaneously lacking the two plasminogen activators, urokinase-type plasminogen activator (u......PA) and tissue-type plasminogen activator (tPA). In contrast, individual genetic deficiencies in either uPA or tPA lead to wound healing kinetics with no or only slightly delayed closure of skin wounds....

  7. Cloning and Analysis of the Promoter Region of Rat uPA Gene

    Institute of Scientific and Technical Information of China (English)

    Yan LIU; Jin-wen XIONG; Li-gang CHEN; Yong-hong TIAN; Cheng-liang XIONG

    2007-01-01

    Objective To clone and analyze the promoter sequence of rat urokinase plasminogen activator protein gene.Methods The genomic DNA was extracted from rat testicular tissue. According to urokinase plasminogen activator, the gene sense primer and antisense primer of uPA gene were designed and synthesized, then Touch-Down PCR were performed. After proper purification, the PCR product was sequenced, analyzed with the promoter prediction software and compared with the DNA sequence of rattuas urokinase plasminogen activator.Results The cloned uPA gene was about 1 572 bp in length, which contained a full open-reading frame with 21 bp in length exons, and the upper region of transcriptional start was 1 551 bp in length which was eucaryon transcriptional control area.The 5' UTR had a promoter region including a non-responsive TATA-box. Not only the GC-box binding region was found in this gene, but also active protein 1 (AP1) and SP1 were seen in other regions.Conclusion A 1 572 bp uPA gene fragment (GenBank accession No. X65651) was obtained from rat genomic DNA library, containing eucaryon transcriptional control area with a promoter region, non-conspicuous TATA-box, GC-box and an extron. A non-responsive TATA-box is located at the upper -30 region.

  8. UPA and PAI-1 analysis from fixed tissues - new perspectives for a known set of predictive markers.

    Science.gov (United States)

    Malinowsky, K; Böllner, C; Hipp, S; Berg, D; Schmitt, M; Becker, K F

    2010-01-01

    The urokinase-type plasminogen activator (uPA) and its main inhibitor PAI-1 play key roles in tumor-associated processes such as the degradation of the extracellular matrix (ECM), tissue remodeling, cell adhesion and migration. Elevated expression of both molecules is known to correlate with negative outcomes in node negative breast cancer. To date, these molecules are the only prognostic markers to have reached the highest level of evidence (LOE I) in multi-centered clinical trials for prognosis of node negative breast cancer. Unfortunately, the clinical utility of these molecules as markers is limited by the use of enzyme-linked immunoassay (ELISA) tests for their detection. The ELISA relies on the use of fresh or frozen tissue, which are rarely available in routine clinical settings. In this review article, we provide an overview of the clinical relevance of uPA and PAI-1 and present alternative methods for their detection. Common uPA and PAI-1 detection methods discussed in literature include RT-PCR-based assays and classical immunohistochemistry approaches. In recent years, attempts have been made to isolate and analyze proteins of formalin fixed, paraffin embedded (FFPE) tissues. These new methods are of special interest because up to now neither RT-PCR nor immunohistochemistry are recommended for the detection of uPA and PAI-1. Here, we present an approach for the analysis of uPA and PAI-1 directly from FFPE tissues that may eventually overcome the limitations of current assays and make the use of both markers widely available for routine prognosis and therapy decisions for breast cancer patients.

  9. Polyphosphates and Polyphosphatase Activity in the Yeast Saccharomyces cerevisiae during Overexpression of the DDP1 Gene.

    Science.gov (United States)

    Trilisenko, L V; Andreeva, N A; Eldarov, M A; Dumina, M V; Kulakovskaya, T V

    2015-10-01

    The effects of overexpression of yeast diphosphoinositol polyphosphate phosphohydrolase (DDP1) having endopolyphosphatase activity on inorganic polyphosphate metabolism in Saccharomyces cerevisiae were studied. The endopolyphosphatase activity in the transformed strain significantly increased compared to the parent strain. This activity was observed with polyphosphates of different chain length, being suppressed by 2 mM tripolyphosphate or ATP. The content of acid-soluble and acid-insoluble polyphosphates under DDP1 overexpression decreased by 9 and 28%, respectively. The average chain length of salt-soluble and alkali-soluble fractions did not change in the overexpressing strain, and that of acid-soluble polyphosphate increased under phosphate excess. At the initial stage of polyphosphate recovery after phosphorus starvation, the chain length of the acid-soluble fraction in transformed cells was lower compared to the recipient strain. This observation suggests the complex nature of DDP1 involvement in the regulation of polyphosphate content and chain length in yeasts.

  10. Assessing behavioural effects of chronic HPA axis activation using conditional CRH-overexpressing mice.

    Science.gov (United States)

    Dedic, Nina; Touma, Chadi; Romanowski, Cristoph P; Schieven, Marcel; Kühne, Claudia; Ableitner, Martin; Lu, Ailing; Holsboer, Florian; Wurst, Wolfgang; Kimura, Mayumi; Deussing, Jan M

    2012-07-01

    The corticotropin-releasing hormone (CRH) and its cognate receptors have been implicated in the pathophysiology of stress-related disorders. Hypersecretion of central CRH and elevated glucocorticoid levels, as a consequence of impaired feedback control, have been shown to accompany mood and anxiety disorders. However, a clear discrimination of direct effects of centrally hypersecreted CRH from those resulting from HPA axis activation has been difficult. Applying a conditional strategy, we have generated two conditional CRH-overexpressing mouse lines: CRH-COE ( Del ) mice overexpress CRH throughout the body, while CRH-COE ( APit ) mice selectively overexpress CRH in the anterior and intermediate lobe of the pituitary. Both mouse lines show increased basal plasma corticosterone levels and consequently develop signs of Cushing's syndrome. However, while mice ubiquitously overexpressing CRH exhibited increased anxiety-related behaviour, overexpression of CRH in the pituitary did not produce alterations in emotional behaviour. These results suggest that chronic hypercorticosteroidism alone is not sufficient to alter anxiety-related behaviour but rather that central CRH hyperdrive on its own or in combination with elevated glucocorticoids is responsible for the increase in anxiety-related behaviour. In conclusion, the generated mouse lines represent valuable animal models to study the consequences of chronic CRH overproduction and HPA axis activation.

  11. Enhanced lysosomal activity by overexpressed aminopeptidase Y in Saccharomyces cerevisiae.

    Science.gov (United States)

    Yoon, Jihee; Sekhon, Simranjeet Singh; Kim, Yang-Hoon; Min, Jiho

    2016-06-01

    Saccharomyces cerevisiae contains vacuoles corresponding to lysosomes in higher eukaryotes. Lysosomes are dynamic (not silent) organelles in which enzymes can be easily integrated or released when exposed to stressful conditions. Changes in lysosomal enzymes have been observed due to oxidative stress, resulting in an increased function of lysosomes. The protein profiles from H2O2- and NH4Cl-treated lysosomes showed different expression patterns, observed with two-dimensional gel electrophoresis. The aminopeptidase Y protein (APE3) that conspicuously enhanced antimicrobial activity than other proteins was selected for further studies. The S. cerevisiae APE3 gene was isolated and inserted into pYES2.0 expression vector. The GFP gene was inserted downstream to the APE3 gene for confirmation of APE3 targeting to lysosomes, and S. cerevisiae was transformed to pYES2::APE3::GFP. The APE3 did not enter in lysosomes and formed an inclusion body at 30 °C, but it inserted to lysosomes as shown by the merger of GFP with lysosomes at 28 °C. Antimicrobial activity of the cloned S. cerevisiae increased about 5 to 10 % against eight strains, compared to normal cells, and galactose induction is increased more two folds than that of normal cells. Therefore, S. cerevisiae was transformed to pYES2::APE3::GFP, accumulating a large amount of APE3, resulting in increased lysosomal activity. Increase in endogenous levels of lysosomes and their activity following genetic modification can lead to its use in applications such as antimicrobial agents and apoptosis-inducing materials for cancer cells, and consequently, it may also be possible to use the organelles for improving in vitro functions.

  12. Overexpression of INCREASED CAMBIAL ACTIVITY, a putative methyltransferase, increases cambial activity and plant growth

    Institute of Scientific and Technical Information of China (English)

    Hyunsook Kim; Mikiko Kojima; Daeseok Choi; Soyoung Park; Minami Matsui; Hitoshi Sakakibara; Ildoo Hwang

    2016-01-01

    Cambial activity is a prerequisite for secondary growth in plants; however, regulatory factors control ing the activity of the secondary meristem in radial growth remain elusive. Here, we identified INCREASED CAMBIAL ACTIVITY (ICA), a gene encoding a putative pectin methyltransferase, which could function as a modulator for the meristematic activity of fascicular and interfascicular cambium in Arabidopsis. An overexpressing transgenic line, 35S::ICA, showed accelerated stem elongation and radial thickening, resulting in increased accumulation of biomass, and increased levels of cytokinins (CKs) and gibberel ins (GAs). Expression of genes encoding pectin methylesterases involved in pectin modification together with pectin methyltransferases was highly induced in 35S::ICA, which might contribute to an increase of methanol emission as a byproduct in 35S::ICA. Methanol treatment induced the expression of GA-or CK-responsive genes and stimulated plant growth. Overal , we propose that ectopic expression of ICA increases cambial activity by regulating CK and GA homeostasis, and methanol emission, eventual y leading to stem elongation and radial growth in the inflorescence stem.

  13. Over-expression of calpastatin inhibits calpain activation and attenuates post-infarction myocardial remodeling.

    Directory of Open Access Journals (Sweden)

    Tingqiao Ye

    Full Text Available Calpain is activated following myocardial infarction and ablation of calpastatin (CAST, an endogenous inhibitor of calpains, promotes left ventricular remodeling after myocardial infarction (MI. The present study aimed to investigate the effect of transgenic over-expression of CAST on the post-infarction myocardial remodeling process.We established transgenic mice (TG ubiquitously over-expressing human CAST protein and produced MI in TG mice and C57BL/6J wild-type (WT littermates.The CAST protein expression was profoundly upregulated in the myocardial tissue of TG mice compared with WT littermates (P < 0.01. Overexpression of CAST significantly reduced the infarct size (P < 0.01 and blunted MI-induced interventricular hypertrophy, global myocardial fibrosis and collagen I and collagen III deposition, hypotension and hemodynamic disturbances at 21 days after MI. Moreover, the MI-induced up-regulation and activation of calpains were obviously attenuated in CAST TG mice. MI-induced down-regulation of CAST was partially reversed in TG mice. Additionally, the MI-caused imbalance of matrix metalloproteinases and their inhibitors was improved in TG mice.Transgenic over-expression of CAST inhibits calpain activation and attenuates post-infarction myocardial remodeling.

  14. Tetrahydrocurcumin inhibits HT1080 cell migration and invasion via downregulation of MMPs and uPA

    Institute of Scientific and Technical Information of China (English)

    Supachai YODKEEREE; Spiridione GARBISA; Pomngarm LIMTRAKUL

    2008-01-01

    Aim: Tetrahydrocurcumin (THC) is an active metabolite of curcumin. It has been reported to have similar pharmacological activity to curcumin. The proteases that participate in extracellular matrix (ECM) degradation are involved in cancer cell metastasis. The present study investigates the effect of an ultimate metabolite of curcumin, THC, on the invasion and motility of highly-metastatic HT1080 human fibrosarcoma cells. Methods: The effect of THC on HTI080 cell invasion and migration was determined using Boyden chamber assay. Cell-adhesion assay was used for examining the binding of cells to ECM molecules. Zymography assay was used to analyze the effect of THC on matrix metalloproteinase (MMP)-2, MMP-9, and urokinase plasminogen activator (uPA) secretion from HT1080 cells. Tissue inhibitor of metalloproteinase (TIMP)-2 and membrane-type 1 matrix metalloproteinase (MT1-MMP) proteins levels were analyzed by Western blotting. Results: Treatment with THC reduced HT1080 cell invasion and migration in a dose-dependent manner. THC also decreased the cell adhesion to Matrigel and laminin-coated plates. Analysis by zymography demonstrated that treatment with THC reduced the levels of MMP-2, MMP-9, and uPA. THC also inhibited the levels of MT1-MMP and TIMP-2 proteins detected by Western blot analysis. Conclusion: Our findings revealed that THC reduced HT1080 cell invasion and migration. The inhibition of cancer cell invasion is associated with the downregulation of ECM degradation enzymes and the inhibition of cell adhesion to ECM proteins.

  15. RhoA/ROCK pathway mediates leptin-induced uPA expression to promote cell invasion in ovarian cancer cells.

    Science.gov (United States)

    Ghasemi, Ahmad; Hashemy, Seyed Isaac; Aghaei, Mahmoud; Panjehpour, Mojtaba

    2017-04-01

    Previous studies have shown that leptin, an adipocyte-secreted hormone, stimulates ovarian cancer invasion. Here, we investigated the contribution of uPA in leptin-induced ovarian cancer cell invasion. The cell invasion and migration experiments were carried out using matrigel invasion and wound healing assays in ovarian cancer cell lines (OVCAR3, SKOV3and CaoV-3). The mechanism underlying the invasive effect of leptin was examined using cell transfection with Ob-Rb siRNA, pre-treatment with a specific inhibitor of RhoA and ROCK, RhoA activation assay, OB-Rb, Rock and upA protein expression. Our results show that leptin induced ovarian cancer cell invasion via up-regulating upA in a time and dose-dependent manner, which was attenuated using knockdown of OB-Rb by siRNA. Moreover, pre-incubation with C3 (inhibitor of RhoA) and Y-27632 (inhibitor of ROCK) effectively attenuated leptin-induced upA expression and inhibited invasive ability of ovarian cancer cells. We also found that pretreatment with inhibitors of PI3K/AKT (LY294002), JAK/STAT (AG490) and NF-kB (BAY 11-7082) significantly reduced leptin-induced upA expression. Collectively, our findings demonstrate that OB-Rb, RhoA/ROCK, PI3K/AKT, JAK/STAT pathways and NF-kB activation are involved in leptin-induced upA expression. These results may provide a new mechanism that facilitates leptin-induced ovarian cancer invasion.

  16. uPA, uPAR and TGFβ₁ expression during early and late post myocardial infarction period in rat myocardium.

    Science.gov (United States)

    Stavropoulou, Anastasia; Philippou, Anastassios; Halapas, Antonios; Sourla, Antigone; Pissimissis, Nikolaos; Koutsilieris, Michael

    2010-01-01

    The expression patterns of transforming growth factor beta 1 (TGFβ₁), urokinase-type plasminogen activator (uPA) and uPA receptor (uPAR) were analysed after artery ligation-induced myocardial infarction (MI) in the rat myocardium. uPA and uPAR expressions were significantly increased both at transcriptional and protein level during early phase post MI period (uPA at 1 hour and uPAR at 24 hours post infarction). TGFβ1 mRNA expression profile revealed a significant increase of TGFβ1 expression from day 4 up to 8 weeks post infarction. These data suggest that the need for an increasing TGFβ₁ bioavailability during the post-infarction period in rat myocardium is achieved in the early post MI period by an increased expression of uPA/uPAR proteolytic system (indirect activation of latent TGFβ₁) and in the late post MI period by direct regulation of TGFβ₁ expression. It is therefore concluded that differential regulation of the TGFβ₁ bioavailability may be a crucial step of the repair mechanisms during the post MI infarction period in the rat myocardium.

  17. Altered expression of urokinase-type plasminogen activator and plasminogen activator inhibitor in high-risk soft tissue sarcomas.

    Science.gov (United States)

    Benassi, M S; Ponticelli, F; Azzoni, E; Gamberi, G; Pazzaglia, L; Chiechi, A; Conti, A; Spessotto, P; Scapolan, M; Pignotti, E; Bacchini, P; Picci, P

    2007-09-01

    In recent years, classification of soft-tissue sarcomas (STS) has improved with cytogenetic analyses, but their clinical behavior is still not easily predictable. The aim of this study was to detect alterations in the urokinase-type plasminogen system, involved in tumor growth and invasion, by comparing mRNA levels of its components with those of paired normal tissues, and relating them with patient clinical course. Real-time PCR was performed on human STS cell lines and tissues from highly malignant STS, including leiomyosarcomas and malignant fibrous histiocytomas, to evaluate the expression of urokinase-type plasminogen activator (uPA), uPA receptor (uPAR) and plasminogen activator inhibitor-1 (PAI-1). Immunohistochemistry of gene products was also performed. Median mRNA values of all genes studied were higher in tumors than in paired normal tissues. In agreement with data on STS cell lines, significant up-regulation for uPA and PAI-1 genes compared to reference values was seen. Moreover, different levels of expression were related to histotype and metastatic phenotype. There was accordance between uPA mRNA and protein expression, while immunodetection of PAI-1 product was weak and scattered. Clearly, the controversial role of PAI-1 protein requires further biological analyses, but evident involvement of uPA/PAI-1 gene overexpression in STS malignancy may highlight a molecular defect useful in discriminating STS high-risk patients.

  18. Overexpressed active Notch1 induces cell growth arrest of HeLa cervical carcinoma cells.

    Science.gov (United States)

    Wang, L; Qin, H; Chen, B; Xin, X; Li, J; Han, H

    2007-01-01

    Human cervical carcinoma is one of the most common malignant tumors, but the mechanisms that orchestrate the multiple oncogenic insults required for initiation and progression are not clear. Notch signaling plays a critical role in maintaining the balance between cell proliferation, differentiation, and apoptosis, but perturbed Notch signaling may contribute to tumorigenesis. We now show that Notch1 is detected in all cervical cancer, including advanced diseases. We also constitutively overexpressed active Notch1 in human cervical carcinoma to explore the effects of Notch1 signaling on human cervical carcinoma cell growth and to investigate the underlying molecular mechanisms. The signaling may participate in the development of human cervical carcinoma cells, but overexpressed active Notch1 inhibits their growth through induction of cell cycle arrest. Increased Notch1 signaling induced a downmodulation of human papillomavirus transcription through suppression of activator protein (AP)-1 activity by upregulation of c-Jun and the decreased expression of c-Fos. Thus, Notch1 signaling plays a key role and exerts dual effects, functioning in context-specific manner.

  19. MSX2 overexpression inhibits gemcitabine-induced caspase-3 activity in pancreatic cancer cells

    Institute of Scientific and Technical Information of China (English)

    Shin Hamada; Kennichi Satoh; Kenji Kimura; Atsushi Kanno; Atsushi Masamune; Tooru Shimosegawa

    2005-01-01

    AIM: To evaluate the effect of MSX2 on gemcitabineinduced caspase-3 activation in pancreatic cancer cell line Panc-1.METHODS: Using V5-tagged MSX2 expression vector,stable transfectant of MSX2 was generated from Panc-1cells (Px14 cells). Cell viability under gemcitabine administration was determined by MTT assay relative to control cell line (empty-vector transfected Panc-1 cells;P-3EV cells). Hoechst staining was used for the detection of apoptotic cell. Activation of caspase-3 was assessed using Western blotting analysis and direct measurement of caspase-3 specific activities.RESULTS: MSX2 overexpression in Panc-1 cells resulted in decreased gemcitabine-induced caspase-3 activation and increased cell viability under gemcitabine treatment in Px14 cells.CONCLUSION: MSX2 exerts repressive effects on gemcitabine-induced apoptotic pathway. This novel apoptosis-regulating function of MSX2 may provide a new therapeutic target for pancreatic cancer.

  20. E2F1 activation is responsible for pituitary adenomas induced by HMGA2 gene overexpression

    Directory of Open Access Journals (Sweden)

    Fusco Alfredo

    2006-08-01

    Full Text Available Abstract The High Mobility Group protein HMGA2 is a nuclear architectural factor that plays a critical role in a wide range of biological processes including regulation of gene expression, embryogenesis and neoplastic transformation. Several studies are trying to identify the mechanisms by which HMGA2 protein is involved in each of these activities, and only recently some new significant insights are emerging from the study of transgenic and knock-out mice. Overexpression of HMGA2 gene leads to the onset of prolactin and GH-hormone induced pituitary adenomas in mice, suggesting a critical role of this protein in pituitary tumorigenesis. This was also confirmed in the human pathology by the finding that HMGA2 amplification and/or overexpression is present in human prolactinomas. This review focuses on recent data that explain the mechanism by which HMGA2 induces the development of pituitary adenomas in mice. This mechanism entails the activation of the E2F1 protein by the HMGA2-mediated displacement of HDAC1 from pRB protein.

  1. Peroxisome proliferator-activated receptor gamma overexpression suppresses proliferation of human colon cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Tsukahara, Tamotsu, E-mail: ttamotsu@shinshu-u.ac.jp [Department of Integrative Physiology and Bio-System Control, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto, Nagano 390-8621 (Japan); Haniu, Hisao [Department of Orthopaedic Surgery, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto, Nagano 390-8621 (Japan)

    2012-08-03

    Highlights: Black-Right-Pointing-Pointer We examined the correlation between PPAR{gamma} expression and cell proliferation. Black-Right-Pointing-Pointer PPAR{gamma} overexpression reduces cell viability. Black-Right-Pointing-Pointer We show the synergistic effect of cell growth inhibition by a PPAR{gamma} agonist. -- Abstract: Peroxisome proliferator-activated receptor gamma (PPAR{gamma}) plays an important role in the differentiation of intestinal cells and tissues. Our previous reports indicate that PPAR{gamma} is expressed at considerable levels in human colon cancer cells. This suggests that PPAR{gamma} expression may be an important factor for cell growth regulation in colon cancer. In this study, we investigated PPAR{gamma} expression in 4 human colon cancer cell lines, HT-29, LOVO, DLD-1, and Caco-2. Real-time polymerase chain reaction (PCR) and Western blot analysis revealed that the relative levels of PPAR{gamma} mRNA and protein in these cells were in the order HT-29 > LOVO > Caco-2 > DLD-1. We also found that PPAR{gamma} overexpression promoted cell growth inhibition in PPAR{gamma} lower-expressing cell lines (Caco-2 and DLD-1), but not in higher-expressing cells (HT-29 and LOVO). We observed a correlation between the level of PPAR{gamma} expression and the cells' sensitivity for proliferation.

  2. P190B RhoGAP overexpression in the developing mammary epithelium induces TGFβ-dependent fibroblast activation.

    Directory of Open Access Journals (Sweden)

    Melissa Gillette

    Full Text Available Rho GTPases mediate stromal-epithelial interactions that are important for mammary epithelial cell (MEC morphogenesis. Increased extracellular matrix (ECM deposition and reorganization affect MEC morphogenesis in a Rho GTPase-dependent manner. Although the effects of altered ECM on MEC morphogenesis have been described, how MECs regulate stromal deposition is not well understood. Previously, we showed that p190B RhoGAP overexpression disrupts mammary gland morphogenesis by inducing hyperbranching in association with stromal alterations. We therefore hypothesized that MEC overexpression of p190B regulates paracrine interactions to impact fibroblast activation. Using a combination of in vivo morphometric and immunohistochemical analyses and primary cell culture assays, we found that p190B overexpression in MECs activates fibroblasts leading to increased collagen, fibronectin, and laminin production and elevated expression of the collagen crosslinking enzyme lysyl oxidase. Phosphorylation of the TGF-β effector SMAD2 and expression of the TGF-β target gene αSma were increased in p190B-associated fibroblasts, suggesting that elevated TGF-β signaling promoted fibroblast activation. Mechanical tension and TGF-β cooperate to activate fibroblasts. Interestingly, active TGF-β was elevated in conditioned medium from p190B overexpressing MECs compared to control MECs, and p190B overexpressing MECs exhibited increased contractility in a collagen gel contraction assay. These data suggest that paracrine signaling from the p190B overexpressing MECs may activate TGF-β signaling in adjacent fibroblasts. In support of this, transfer of conditioned medium from p190B overexpressing MECs onto wildtype fibroblasts or co-culture of p190B overexpressing MECs with wildtype fibroblasts increased SMAD2 phosphorylation and mRNA expression of ECM genes in the fibroblasts when compared to fibroblasts treated with control CM or co-cultured with control MECs. The

  3. Characterization of human endothelial cell urokinase-type plasminogen activator receptor protein and messenger RNA

    DEFF Research Database (Denmark)

    Barnathan, E S; Kuo, A; Karikó, K

    1990-01-01

    Human umbilical vein endothelial cells in culture (HUVEC) express receptors for urokinase-type plasminogen activators (u-PA). The immunochemical nature of this receptor and its relationship to u-PA receptors expressed by other cell types is unknown. Cross-linking active site-blocked u-PA to HUVEC...

  4. CARMA3 is overexpressed in colon cancer and regulates NF-{kappa}B activity and cyclin D1 expression

    Energy Technology Data Exchange (ETDEWEB)

    Miao, Zhifeng; Zhao, Tingting; Wang, Zhenning; Xu, Yingying; Song, Yongxi; Wu, Jianhua [Department of General Surgery, First Affiliated Hospital of China Medical University, Shenyang (China); Xu, Huimian, E-mail: xuhuimianpaper@yahoo.com.cn [Department of General Surgery, First Affiliated Hospital of China Medical University, Shenyang (China)

    2012-09-07

    Highlights: Black-Right-Pointing-Pointer CARMA3 expression is elevated in colon cancers. Black-Right-Pointing-Pointer CARMA3 promotes proliferation and cell cycle progression in colon cancer cells. Black-Right-Pointing-Pointer CARMA3 upregulates cyclinD1 through NF-{kappa}B activation. -- Abstract: CARMA3 was recently reported to be overexpressed in cancers and associated with the malignant behavior of cancer cells. However, the expression of CARMA3 and its biological roles in colon cancer have not been reported. In the present study, we analyzed the expression pattern of CARMA3 in colon cancer tissues and found that CARMA3 was overexpressed in 30.8% of colon cancer specimens. There was a significant association between CARMA3 overexpression and TNM stage (p = 0.0383), lymph node metastasis (p = 0.0091) and Ki67 proliferation index (p = 0.0035). Furthermore, knockdown of CARMA3 expression in HT29 and HCT116 cells with high endogenous expression decreased cell proliferation and cell cycle progression while overexpression of CARMA3 in LoVo cell line promoted cell proliferation and facilitated cell cycle transition. Further analysis showed that CARMA3 knockdown downregulated and its overexpression upregulated cyclin D1 expression and phospho-Rb levels. In addition, we found that CARMA3 depletion inhibited p-I{kappa}B levels and NF-{kappa}B activity and its overexpression increased p-I{kappa}B expression and NF-{kappa}B activity. NF-{kappa}B inhibitor BAY 11-7082 reversed the role of CARMA3 on cyclin D1 upregulation. In conclusion, our study found that CARMA3 is overexpressed in colon cancers and contributes to malignant cell growth by facilitating cell cycle progression through NF-{kappa}B mediated upregulation of cyclin D1.

  5. The plasminogen activation system modulates differently adipogenesis and myogenesis of embryonic stem cells.

    Directory of Open Access Journals (Sweden)

    Ola Hadadeh

    Full Text Available Regulation of the extracellular matrix (ECM plays an important functional role either in physiological or pathological conditions. The plasminogen activation (PA system, comprising the uPA and tPA proteases and their inhibitor PAI-1, is one of the main suppliers of extracellular proteolytic activity contributing to tissue remodeling. Although its function in development is well documented, its precise role in mouse embryonic stem cell (ESC differentiation in vitro is unknown. We found that the PA system components are expressed at very low levels in undifferentiated ESCs and that upon differentiation uPA activity is detected mainly transiently, whereas tPA activity and PAI-1 protein are maximum in well differentiated cells. Adipocyte formation by ESCs is inhibited by amiloride treatment, a specific uPA inhibitor. Likewise, ESCs expressing ectopic PAI-1 under the control of an inducible expression system display reduced adipogenic capacities after induction of the gene. Furthermore, the adipogenic differentiation capacities of PAI-1(-/- induced pluripotent stem cells (iPSCs are augmented as compared to wt iPSCs. Our results demonstrate that the control of ESC adipogenesis by the PA system correspond to different successive steps from undifferentiated to well differentiated ESCs. Similarly, skeletal myogenesis is decreased by uPA inhibition or PAI-1 overexpression during the terminal step of differentiation. However, interfering with uPA during days 0 to 3 of the differentiation process augments ESC myotube formation. Neither neurogenesis, cardiomyogenesis, endothelial cell nor smooth muscle formation are affected by amiloride or PAI-1 induction. Our results show that the PA system is capable to specifically modulate adipogenesis and skeletal myogenesis of ESCs by successive different molecular mechanisms.

  6. Up-Regulation of PAI-1 and Down-Regulation of uPA Are Involved in Suppression of Invasiveness and Motility of Hepatocellular Carcinoma Cells by a Natural Compound Berberine.

    Science.gov (United States)

    Wang, Xuanbin; Wang, Ning; Li, Hongliang; Liu, Ming; Cao, Fengjun; Yu, Xianjun; Zhang, Jingxuan; Tan, Yan; Xiang, Longchao; Feng, Yibin

    2016-04-16

    Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related death and its prognosis remains poor due to the high risk of tumor recurrence and metastasis. Berberine (BBR) is a natural compound derived from some medicinal plants, and accumulating evidence has shown its potent anti-tumor activity with diverse action on tumor cells, including inducing cancer cell death and blocking cell cycle and migration. Molecular targets of berberine involved in its inhibitory effect on the invasiveness remains not yet clear. In this study, we identified that berberine exhibits a potent inhibition on the invasion and migration of HCC cells. This was accompanied by a dose-dependent down-regulation of expression of Cyclooxygenase-2 (COX-2), nuclear factor kappa B (NF-κB), urokinase-type plasminogen activator (uPA) and matrix metalloproteinase (MMP)-9 in berberine-treated HCC cells. Furthermore, berberine inactivated p38 and Erk1/2 signaling pathway in HCC cells. Primarily, this may be attributed to the up-regulation of plasminogen activator inhibitor-1 (PAI-1), a tumor suppressor that can antagonize uPA receptor and down-regulation of uPA. Blockade of uPA receptor-associated pathways leads to reduced invasiveness and motility of berberine-treated HCC cells. In conclusion, our findings identified for the first time that inactivation of uPA receptor by up-regulation of PAI-1 and down-regulation of uPA is involved in the inhibitory effect of berberine on HCC cell invasion and migration.

  7. Common TNF-alpha, IL-1 beta, PAI-1, uPA, CD14 and TLR4 polymorphisms are not associated with disease severity or outcome from Gram negative sepsis

    DEFF Research Database (Denmark)

    Jessen, Kirstine Marie; Lindboe, Sarah Bjerre; Petersen, Anncatrine Luisa

    2007-01-01

    consecutive adult patients with culture proven Gram negative bacteremia admitted to a Danish hospital between 2000 and 2002. Analysis for commonly described SNPs of tumor necrosis-alpha, (TNF-alpha), interleukin-1 beta (IL-1 beta), plasminogen activator-1 (PAI-1), urokinase plasminogen activator (uPA), CD14...

  8. Rap1 overexpression reveals that activated RasD induces separable defects during Dictyostelium development.

    Science.gov (United States)

    Louis, S A; Weeks, G; Spiegelman, G B

    1997-10-15

    One of the Dictyostelium ras genes, rasD, is expressed preferentially in prestalk cells at the slug stage of development and overexpression of this gene containing a G12T activating mutation causes the formation of aberrant multitipped aggregates that are blocked from further development (Reymond et al., 1986, Nature, 323, 340-343). The ability of the Dictyostelium rap1 gene to suppress this abnormal developmental phenotype was investigated. The rap1 gene and G12V activated and G10V negative mutant forms of the rap1 gene were independently linked to the rasD promoter and each construct used to transform M1, a Dictyostelium cell line expressing RasD[G12T]. Transformants of M1 that expressed Rap1 or Rap1[G12V] protein still formed multitipped aggregates, but most tips were able to complete development and form fruiting bodies. Cell lines showing this modified phenotype were designated ME (multitipped escape). The rap1[G10V] construct did not modify the M1 phenotype. These data suggest that overexpression of RasD[G12T] has two effects, the formation of a multitipped aggregate and a block in subsequent differentiation and that the expression of Rap1 or Rap1[G12V] reverses only the latter. Differentiation of ME cells in low density monolayers showed the identical low level of stalk and spore cell formation seen for M1 cells under the same conditions. Thus the cell autonomous defect in monolayer differentiation induced in the M1 strain was not corrected in the ME strain. Cell type-specific gene expression during the development of M1 cells is dramatically altered: prestalk cell-specific gene expression is greatly enhanced, whereas prespore-specific gene expression is almost suppressed (Louis et al., 1997, Mol. Biol. Cell, 8, 303-312). During the development of ME cells, ecmA mRNA levels were restored to those seen for Ax3, and tagB mRNA levels were also markedly reduced, although not to Ax3 levels. cotC expression in ME cells was enhanced severalfold relative to M1

  9. Overexpression of the trichodiene synthase gene tri5 increases trichodermin production and antimicrobial activity in Trichoderma brevicompactum.

    Science.gov (United States)

    Tijerino, Anamariela; Cardoza, R Elena; Moraga, Javier; Malmierca, Mónica G; Vicente, Francisca; Aleu, Josefina; Collado, Isidro G; Gutiérrez, Santiago; Monte, Enrique; Hermosa, Rosa

    2011-03-01

    Trichoderma brevicompactum produces trichodermin, a simple trichothecene-type toxin that shares the first steps of the sesquiterpene biosynthetic pathway with other phytotoxic trichothecenes from Fusarium spp. Trichodiene synthase catalyses the conversion of farnesyl pyrophosphate to trichodiene and it is encoded by the tri5 gene that was cloned and analysed functionally by homologous overexpression in T. brevicompactum. tri5 expression was up-regulated in media with glucose, H(2)O(2) or glycerol. tri5 repression was observed in cultures supplemented with the antioxidants ferulic acid and tyrosol. Acetone extracts of tri5-overexpressing transformants displayed higher antifungal activity than those from the wild-type. Chromatographic and spectroscopic analyses revealed that tri5 overexpression led to an increased production of trichodermin and tyrosol. Agar diffusion assays with these two purified metabolites from the tri5-overexpressing transformant T. brevicompactum Tb41tri5 showed that only trichodermin had antifungal activity against Saccharomyces cerevisiae, Kluyveromyces marxianus, Candida albicans, Candida glabrata, Candida tropicalis and Aspergillus fumigatus, in most cases such activity being higher than that observed for amphotericin B and hygromycin. Our results point to the significant role of tri5 in the production of trichodermin and in the antifungal activity of T. brevicompactum.

  10. Insulin receptor-overexpressing β-cells ameliorate hyperglycemia in diabetic rats through Wnt signaling activation.

    Directory of Open Access Journals (Sweden)

    Mi-Hyun Kim

    Full Text Available To investigate the therapeutic efficacy and mechanism of β-cells with insulin receptor (IR overexpression on diabetes mellitus (DM, rat insulinoma (INS-1 cells were engineered to stably express human insulin receptor (INS-IR cells, and subsequently transplanted into streptozotocin- induced diabetic rats. Compared with INS-1 cells, INS-IR cells showed improved β-cell function, including the increase in glucose utilization, calcium mobilization, and insulin secretion, and exhibited a higher rate of cell proliferation, and maintained lower levels of blood glucose in diabetic rats. These results were attributed to the increase of β-catenin/PPARγ complex bindings to peroxisome proliferator response elements in rat glucokinase (GK promoter and the prolongation of S-phase of cell cycle by cyclin D1. These events resulted from more rapid and higher phosphorylation levels of insulin-signaling intermediates, including insulin receptor substrate (IRS-1/IRS-2/phosphotylinositol 3 kinase/v-akt murine thymoma viral oncogene homolog (AKT 1, and the consequent enhancement of β-catenin nuclear translocation and Wnt responsive genes including GK and cyclin D1. Indeed, the higher functionality and proliferation shown in INS-IR cells were offset by β-catenin, cyclin D1, GK, AKT1, and IRS-2 gene depletion. In addition, the promotion of cell proliferation and insulin secretion by Wnt signaling activation was shown by 100 nM insulin treatment, and to a similar degree, was shown in INS-IR cells. In this regard, this study suggests that transferring INS-IR cells into diabetic animals is an effective and feasible DM treatment. Accordingly, the method might be a promising alternative strategy for treatment of DM given the adverse effects of insulin among patients, including the increased risk of modest weight gain and hypoglycemia. Additionally, this study demonstrates that the novel mechanism of cross-talk between insulin and Wnt signaling plays a primary role in

  11. Overexpression of plastidial thioredoxins f and m differentially alters photosynthetic activity and response to oxidative stress in tobacco plants

    Directory of Open Access Journals (Sweden)

    Pascal eREY

    2013-10-01

    Full Text Available Plants display a remarkable diversity of thioredoxins (Trxs, reductases controlling the thiol redox status of proteins. The physiological function of many of them remains elusive, particularly for plastidial Trxs f and m, which are presumed based on biochemical data to regulate photosynthetic reactions and carbon metabolism. Recent reports revealed that Trxs f and m participate in vivo in the control of starch metabolism and cyclic photosynthetic electron transfer around photosystem I, respectively. To further delineate their in planta function, we compared the photosynthetic characteristics, the level and/or activity of various Trx targets and the responses to oxidative stress in transplastomic tobacco plants overexpressing either Trx f or Trx m. We found that plants overexpressing Trx m specifically exhibit altered growth, reduced chlorophyll content, impaired photosynthetic linear electron transfer and decreased pools of glutathione and ascorbate. In both transplastomic lines, activities of two enzymes involved in carbon metabolism, NADP-malate dehydrogenase and NADP-glyceraldehyde-3-phosphate dehydrogenase are markedly and similarly altered. In contrast, plants overexpressing Trx m specifically display increased capacity for methionine sulfoxide reductases, enzymes repairing damaged proteins by regenerating methionine from oxidized methionine. Finally, we also observed that transplastomic plants exhibit distinct responses when exposed to oxidative stress conditions generated by methyl viologen or exposure to high light combined with low temperature, the plants overexpressing Trx m being notably more tolerant than Wt and those overexpressing Trx f. Altogether, these data indicate that Trxs f and m fulfill distinct physiological functions. They prompt us to propose that the m type is involved in key processes linking photosynthetic activity, redox homeostasis and antioxidant mechanisms in the chloroplast.

  12. 尿激酶(uPA)化学合成抑制剂%Synthetic Inhibitors of uPA

    Institute of Scientific and Technical Information of China (English)

    李永东; 王华; 曾丹; 郭道义; 李勋; 范小林

    2011-01-01

    胞外蛋白的水解是恶性肿瘤细胞侵袭和转移的必要条件,各种蛋白酶的水解反应降解细胞外基质,破坏细胞/细胞间的联系以适应细胞的迁移。尿激酶型纤溶酶原激活物(尿激酶,urokinase—typeplasminogen activator,uPA)激活不具有丝氨酸蛋白酶活性的纤溶酶原为活性纤溶酶,在保持血流畅通与防止血栓的形成中具有重要的作用。此外,活性尿激酶降解细胞外基质,激活多种基质金属蛋白酶,以适应肿瘤细胞的侵袭、扩散和转移。抑制尿激酶的活性被公认为是抑制癌症转移的有效方法,其中合成小分子uPA抑制剂成为抗癌%The extracellular proteolysis is the necessary condition for the malignant process of tumor invasion and metastasis. These proteolytic reactions destruct the cell-cell and cell/ECM contacts and degrade the extracellular matrix (ECM) components which pose physical obstacle in the direction of migration/invasion. Urokinase-type plasminogen activator (uPA), which can activate the inactive plasminogen to plasmin, plays a pivotal role in clot lysis and keeps the blood flowing. Moreover, active uPA degrades ECM and activates a number of matrix metalloproteases, beginning a cascade of events adapting to the cancer cell invasion, spread and metastasis. The inhibition of uPA activity has been recognized as an efficient method in the treatment of cancer by retarding tumor growth and metastasis and inhibition of urokinase with synthetic inhibitor is a new concept for specific cancer therapy. Here we review the current research status of synthetic uPA inhibitors.

  13. Reversibility of epithelial-mesenchymal transition (EMT) induced in breast cancer cells by activation of urokinase receptor-dependent cell signaling.

    Science.gov (United States)

    Jo, Minji; Lester, Robin D; Montel, Valerie; Eastman, Boryana; Takimoto, Shinako; Gonias, Steven L

    2009-08-21

    Hypoxia induces expression of the urokinase receptor (uPAR) and activates uPAR-dependent cell signaling in cancer cells. This process promotes epithelial-mesenchymal transition (EMT). uPAR overexpression in cancer cells also promotes EMT. In this study, we tested whether uPAR may be targeted to reverse cancer cell EMT. When MDA-MB 468 breast cancer cells were cultured in 1% O(2), uPAR expression increased, as anticipated. Cell-cell junctions were disrupted, vimentin expression increased, and E-cadherin was lost from cell surfaces, indicating EMT. Transferring these cells back to 21% O(2) decreased uPAR expression and reversed the signs of EMT. In uPAR-overexpressing MDA-MB 468 cells, EMT was reversed by silencing expression of endogenously produced urokinase-type plasminogen activator (uPA), which is necessary for uPAR-dependent cell signaling, or by targeting uPAR-activated cell signaling factors, including phosphatidylinositol 3-kinase, Src family kinases, and extracellular signal-regulated kinase. MDA-MB 231 breast cancer cells express high levels of uPA and uPAR and demonstrate mesenchymal cell morphology under normoxic culture conditions (21% O(2)). Silencing uPA expression in MDA-MB-231 cells decreased expression of vimentin and Snail, and induced changes in morphology characteristic of epithelial cells. These results demonstrate that uPAR-initiated cell signaling may be targeted to reverse EMT in cancer.

  14. YB-1 overexpression promotes a TGF-β1-induced epithelial–mesenchymal transition via Akt activation

    Energy Technology Data Exchange (ETDEWEB)

    Ha, Bin; Lee, Eun Byul; Cui, Jun; Kim, Yosup [Department of Molecular Medicine, Lee Gil Ya Cancer and Diabetes Institute, Gachon University, Incheon 406-799 (Korea, Republic of); Jang, Ho Hee, E-mail: hhjang@gachon.ac.kr [Department of Molecular Medicine, Lee Gil Ya Cancer and Diabetes Institute, Gachon University, Incheon 406-799 (Korea, Republic of); Gachon Medical Research Institute, Gil Medical Center, Gachon University, Incheon (Korea, Republic of)

    2015-03-06

    The Y-box binding protein-1 (YB-1) is a transcription/translation regulatory protein, and the expression thereof is associated with cancer aggressiveness. In the present study, we explored the regulatory effects of YB-1 during the transforming growth factor-β1 (TGF-β1)-induced epithelial-to-mesenchymal transition (EMT) in lung adenocarcinoma cells. Downregulation of YB-1 increased E-cadherin promoter activity, and upregulation of YB-1 decreased promoter activity, suggesting that the YB-1 level may be correlated with the EMT. TGF-β1 induced YB-1 expression, and TGF-β1 translocated cytosolic YB-1 into the nucleus. YB-1 overexpression promoted TGF-β1-induced downregulation of epithelial markers, upregulation of mesenchymal markers, and cell migration. Moreover, YB-1 overexpression enhanced the expression of E-cadherin transcriptional repressors via TGF-β1-induced Akt activation. Our findings afford new insights into the role played by YB-1 in the TGF-β1 signaling pathway. - Highlights: • YB-1 regulates E-cadherin expression in A549 cells. • TGF-β1 induces upregulating and nuclear localization of YB-1. • YB-1 overexpression accelerates TGF-β1-induced EMT and cell migration. • YB-1 regulates Snail and Slug expression via Akt activation.

  15. Effect of the over-expression of PII and PZ proteins on the nitrogenase activity of Azospirillum brasilense.

    Science.gov (United States)

    Huergo, Luciano F; Filipaki, Angela; Chubatsu, Leda S; Yates, M Geoffrey; Steffens, Maria Berenice; Pedrosa, Fabio O; Souza, Emanuel M

    2005-12-01

    The Azospirillum brasilense PII and PZ proteins, encoded by the glnB and glnZ genes respectively, are intracellular transducers of nitrogen levels with distinct functions. The PII protein participates in nif regulation by controlling the activity of the transcriptional regulator NifA. PII is also involved in transducing the prevailing nitrogen levels to the Fe-protein ADP-ribosylation system. PZ regulates negatively ammonium transport and is involved in nitrogenase reactivation. To further investigate the role of PII and PZ in the regulation of nitrogen fixation, broad-host-range plasmids capable of over-expressing the glnB and glnZ genes under control of the ptac promoter were constructed and introduced into A. brasilense. The nitrogenase activity and nitrate-dependent growth was impaired in A. brasilense cells over-expressing the PII protein. Using immunoblot analysis we observed that the reduction of nitrogenase activity in cells over-expressing PII was due to partial ADP-ribosylation of the Fe-protein under derepressing conditions and a reduction in the amount of Fe-protein. These results support the hypothesis that the unmodified PII protein act as a signal to the DraT enzyme to ADP-ribosylate the Fe-protein in response to ammonium shock, and that it also inhibits nif gene expression. In cells over-expressing the PZ protein the nitrogenase reactivation after an ammonium shock was delayed indicating that the PZ protein is involved in regulation of DraG activity.

  16. Uniform {sup 15}N- and {sup 15}N/{sup 13}C-labeling of proteins in mammalian cells and solution structure of the amino terminal fragment of u-PA

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, A.P.; Petros, A.M.; Meadows, R.P.; Mazar, A.P.; Nettesheim, D.G.; Pederson, T.M.; Fesik, S.W. [Abbott Laboratories, Abbott Park, IL (United States)

    1994-12-01

    Urokinase-type plasminogen activator (u-PA) is a 54-kDa glycoprotein that catalyzes the conversion of plasminogen to plasmin, a broad-specificity protease responsible for the degradation of fibrin clots and extracellular matrix components. The u-PA protein consists of three individual modules: a growth factor domain (GFD), a kringle, and a serine protease domain. The amino terminal fragment (ATF) includes the GFD-responsible for u-PA binding to its receptor-and the kringle domains. This protein was expressed and uniformly {sup 15}N-and {sup 15}N/{sup 13}C-labeled in mammalian cells by methods that will be described. In addition, we present the three-dimensional structure of ATF that was derived from 1299 NOE-derived distance restraints along with the {phi} angle and hydrogen bonding restraints. Although the individual domains in the structures were highly converged, the two domains are structurally independent. The overall structures of the individual domains are very similar to the structures of homologous proteins. However, important structural differences between the growth factor domain of u-PA and other homologous proteins were observed in the region that has been implicated in binding the urokinase receptor. These results may explain, in part, why other growth factors show no appreciable affinity for the urokinase receptor.

  17. Enhancement of Spontaneous Activity by HCN4 Overexpression in Mouse Embryonic Stem Cell-Derived Cardiomyocytes - A Possible Biological Pacemaker.

    Directory of Open Access Journals (Sweden)

    Yukihiro Saito

    Full Text Available Establishment of a biological pacemaker is expected to solve the persisting problems of a mechanical pacemaker including the problems of battery life and electromagnetic interference. Enhancement of the funny current (If flowing through hyperpolarization-activated cyclic nucleotide-gated (HCN channels and attenuation of the inward rectifier K+ current (IK1 flowing through inward rectifier potassium (Kir channels are essential for generation of a biological pacemaker. Therefore, we generated HCN4-overexpressing mouse embryonic stem cells (mESCs and induced cardiomyocytes that originally show poor IK1 currents, and we investigated whether the HCN4-overexpressing mESC-derived cardiomyocytes (mESC-CMs function as a biological pacemaker in vitro.The rabbit Hcn4 gene was transfected into mESCs, and stable clones were selected. mESC-CMs were generated via embryoid bodies and purified under serum/glucose-free and lactate-supplemented conditions. Approximately 90% of the purified cells were troponin I-positive by immunostaining. In mESC-CMs, expression level of the Kcnj2 gene encoding Kir2.1, which is essential for generation of IK1 currents that are responsible for stabilizing the resting membrane potential, was lower than that in an adult mouse ventricle. HCN4-overexpressing mESC-CMs expressed about a 3-times higher level of the Hcn4 gene than did non-overexpressing mESC-CMs. Expression of the Cacna1h gene, which encodes T-type calcium channel and generates diastolic depolarization in the sinoatrial node, was also confirmed. Additionally, genes required for impulse conduction including Connexin40, Connexin43, and Connexin45 genes, which encode connexins forming gap junctions, and the Scn5a gene, which encodes sodium channels, are expressed in the cells. HCN4-overexpressing mESC-CMs showed significantly larger If currents and more rapid spontaneous beating than did non-overexpressing mESC-CMs. The beating rate of HCN4-overexpressing mESC-CMs responded

  18. CARD15 gene overexpression reduces effect of etanercept, infliximab, and adalimumab on cytokine secretion from PMA activated U937 cells.

    Science.gov (United States)

    Teimourian, Shahram; Masoudzadeh, Nooshin

    2015-09-05

    Crohn's disease (CD), a subcategory of inflammatory bowel disease, is an immune-related disorder characterized by inflammation of the gastrointestinal mucosa, which can take place in any region along the alimentary tract. The most important gene involved in the etiology of CD is NOD2/CARD15 located on chromosome 16. It has been shown that CARD15 is overexpressed in monocytes of CD patients. The common treatment for the disease is anti-TNF-alpha drugs, the most hopeful of which are probably infliximab and etanercept. Infliximab rapidly reduces signs and symptoms of active Crohn's disease. In contrast, etanercept shows no such effect. In the present study, we evaluated the effects of the CARD15 gene overexpression in monocytic cell line U937 in the production of anti-inflammatory cytokine, IL-10, and proinflammatory cytokine, Il-1 beta, produced after incubation with infliximab, adalimumab, and etanercept separately. Our results show that infliximab and adalimumab significantly decreased IL-10 and IL-1beta secretion levels. However, etanercept inhibition of secretion was less compared with infliximab or adalimumab. In all three cases, suppression of cytokine production is reduced by CARD15 overexpression.

  19. Overexpression of a novel activator of PAK4, the CDK5 kinase-associated protein CDK5RAP3, promotes hepatocellular carcinoma metastasis.

    Science.gov (United States)

    Mak, Grace Wing-Yan; Chan, Mandy Man-Lok; Leong, Veronica Yee-Law; Lee, Joyce Man-Fong; Yau, Tai-On; Ng, Irene Oi-Lin; Ching, Yick-Pang

    2011-04-15

    The CDK5 kinase regulatory subunit-associated protein 3 (CDK5RAP3 or C53/LZAP) regulates apoptosis induced by genotoxic stress. Although CDK5RAP3 has been implicated in cancer progression, its exact role in carcinogenesis is not well established. In this article, we report that CDK5RAP3 has an important prometastatic function in hepatocarcinogenesis. An examination of human hepatocellular carcinoma (HCC) samples revealed at least twofold overexpression of CDK5RAP3 transcripts in 58% (39/67) of HCC specimens when compared with corresponding nontumorous livers. CDK5RAP3 overexpression was associated with more aggressive biological behavior. In HCC cell lines, stable overexpression of CDK5RAP3 promoted, and small interfering RNA-mediated knockdown inhibited, tumorigenic activity and metastatic potential. We found that overexpression of CDK5RAP3 and p21-activated protein kinase 4 (PAK4) correlated in human HCCs, and that CDK5RAP3 was a novel binding partner of PAK4, and this binding enhanced PAK4 activity. siRNA-mediated knockdown of PAK4 in CDK5RAP3-expressing HCC cells reversed the enhanced cell invasiveness mediated by CDK5RAP3 overexpression, implying that PAK4 is essential for CDK5RAP3 function. Taken together, our findings reveal that CDK5RAP3 is widely overexpressed in HCC and that overexpression of CDK5RAP3 promotes HCC metastasis through PAK4 activation.

  20. Phenotypic alterations in breast cancer cells overexpressing the nuclear receptor co-activator AIB1

    Directory of Open Access Journals (Sweden)

    Azorsa David O

    2003-09-01

    Full Text Available Abstract Background Estrogen signaling plays a critical role in a number of normal physiological processes and has important implications in the treatment of breast cancer. The p160 nuclear receptor coactivator, AIB1 (amplified in breast cancer 1, is frequently amplified and overexpressed in human breast cancer and has been shown to enhance estrogen-dependent transactivation. Methods To better understand the molecular and physiological consequences of AIB1 overexpression in breast cancer cells, an AIB1 cDNA was transfected into the low AIB1 expressing, estrogen-receptor (ER negative breast cancer cell line, MDA-MB-436. The features of a derivative cell line, designated 436.1, which expresses high levels of AIB1, are described and compared with the parental cell line. Results A significant increase in the levels of CREB binding protein (CBP was observed in 436.1 cells and immunofluorescent staining revealed altered AIB1 and CBP staining patterns compared to the parental cells. Further, transient transfection assays demonstrated that the overall estrogen-dependent transactivation in 436.1 cells is approximately 20-fold higher than the parental cells and the estrogen dose-response curve is repositioned to the right. Finally, cDNA microarray analysis of approximately 7,100 cDNAs identified a number of differentially expressed genes in the 436.1 cells. Conclusion These observations lend insight into downstream signaling pathways that are influenced by AIB1.

  1. Lysophosphatidic acid activates peroxisome proliferator activated receptor-γ in CHO cells that over-express glycerol 3-phosphate acyltransferase-1.

    Directory of Open Access Journals (Sweden)

    Cliona M Stapleton

    Full Text Available Lysophosphatidic acid (LPA is an agonist for peroxisome proliferator activated receptor-γ (PPARγ. Although glycerol-3-phosphate acyltransferase-1 (GPAT1 esterifies glycerol-3-phosphate to form LPA, an intermediate in the de novo synthesis of glycerolipids, it has been assumed that LPA synthesized by this route does not have a signaling role. The availability of Chinese Hamster Ovary (CHO cells that stably overexpress GPAT1, allowed us to analyze PPARγ activation in the presence of LPA produced as an intracellular intermediate. LPA levels in CHO-GPAT1 cells were 6-fold higher than in wild-type CHO cells, and the mRNA abundance of CD36, a PPARγ target, was 2-fold higher. Transactivation assays showed that PPARγ activity was higher in the cells that overexpressed GPAT1. PPARγ activity was enhanced further in CHO-GPAT1 cells treated with the PPARγ ligand troglitazone. Extracellular LPA, phosphatidic acid (PA or a membrane-permeable diacylglycerol had no effect, showing that PPARγ had been activated by LPA generated intracellularly. Transient transfection of a vector expressing 1-acylglycerol-3-phosphate acyltransferase-2, which converts endogenous LPA to PA, markedly reduced PPARγ activity, as did over-expressing diacylglycerol kinase, which converts DAG to PA, indicating that PA could be a potent inhibitor of PPARγ. These data suggest that LPA synthesized via the glycerol-3-phosphate pathway can activate PPARγ and that intermediates of de novo glycerolipid synthesis regulate gene expression.

  2. Cytosolic phospholipase A2 activation correlates with HER2 overexpression and mediates estrogen-dependent breast cancer cell growth.

    LENUS (Irish Health Repository)

    Caiazza, Francesco

    2010-05-01

    Cytosolic phospholipase A(2)alpha (cPLA(2)alpha) catalyzes the hydrolysis of membrane glycerol-phospholipids to release arachidonic acid as the first step of the eicosanoid signaling pathway. This pathway contributes to proliferation in breast cancer, and numerous studies have demonstrated a crucial role of cyclooxygenase 2 and prostaglandin E(2) release in breast cancer progression. The role of cPLA(2)alpha activation is less clear, and we recently showed that 17beta-estradiol (E2) can rapidly activate cPLA(2)alpha in MCF-7 breast cancer cells. Overexpression or gene amplification of HER2 is found in approximately 30% of breast cancer patients and correlates with a poor clinical outcome and resistance to endocrine therapy. This study reports the first evidence for a correlation between cPLA(2)alpha enzymatic activity and overexpression of the HER2 receptor. The activation of cPLA(2)alpha in response to E2 treatment was biphasic with the first phase dependent on trans-activation through the matrix metalloproteinase-dependent release of heparin-bound epidermal growth factor. EGFR\\/HER2 heterodimerization resulted in downstream signaling through the ERK1\\/2 cascade to promote cPLA(2)alpha phosphorylation at Ser505. There was a correlation between HER2 and cPLA(2)alpha expression in six breast cancer cell lines examined, and inhibition of HER2 activation or expression in the SKBR3 cell line using herceptin or HER2-specific small interfering RNA, respectively, resulted in decreased activation and expression of cPLA(2)alpha. Pharmacological blockade of cPLA(2)alpha using a specific antagonist suppressed the growth of both MCF-7 and SKBR3 cells by reducing E2-induced proliferation and by stimulating cellular apoptosis and necrosis. This study highlights cPLAalpha(2) as a potential target for therapeutic intervention in endocrine-dependent and endocrine-independent breast cancer.

  3. Induction of HSPA4 and HSPA14 by NBS1 overexpression contributes to NBS1-induced in vitro metastatic and transformation activity

    Directory of Open Access Journals (Sweden)

    Lin Chih-Ta

    2011-01-01

    Full Text Available Abstract Background Nijmegen breakage syndrome (NBS is a chromosomal-instability syndrome associated with cancer predisposition, radiosensitivity, microcephaly, and growth retardation. The NBS gene product, NBS1 (p95 or nibrin, is a part of the MRN complex, a central player associated with double-strand break (DSB repair. We previously demonstrated that NBS1 overexpression contributes to transformation through the activation of PI 3-kinase/Akt. NBS1 overexpression also induces epithelial-mesenchymal transition through the Snail/MMP2 pathway. Methods RT-PCR, Western blot analysis, in vitro migration/invasion, soft agar colony formation, and gelatin zymography assays were performed. Results Here we show that heat shock protein family members, A4 and A14, were induced by NBS1 overexpression. siRNA mediated knockdown of HSPA4 or HSPA14 decreased the in vitro migration, invasion, and transformation activity in H1299 cells overexpressing NBS1. However, HSPA4 or HSPA14 induced activity was not mediated through MMP2. NBS1 overexpression induced the expression of heat shock transcription factor 4b (HSF4b, which correlated with the expression of HSPA4 and HSPA14. Conclusion These results identify a novel pathway (NBS1-HSF4b-HSPA4/HSPA14 axis to induce migration, invasion, and transformation, suggesting the activation of multiple signaling events induced by NBS1 overexpression.

  4. GIGANTEA enables drought escape response via abscisic acid-dependent activation of the florigens and SUPPRESSOR OF OVEREXPRESSION OF CONSTANS.

    Science.gov (United States)

    Riboni, Matteo; Galbiati, Massimo; Tonelli, Chiara; Conti, Lucio

    2013-07-01

    Modulation of the transition to flowering plays an important role in the adaptation to drought. The drought-escape (DE) response allows plants to adaptively shorten their life cycle to make seeds before severe stress leads to death. However, the molecular basis of the DE response is unknown. A screen of different Arabidopsis (Arabidopsis thaliana) flowering time mutants under DE-triggering conditions revealed the central role of the flower-promoting gene GIGANTEA (GI) and the florigen genes FLOWERING LOCUS T (FT) and TWIN SISTER OF FT (TSF) in the DE response. Further screens showed that the phytohormone abscisic acid is required for the DE response, positively regulating flowering under long-day conditions. Drought stress promotes the transcriptional up-regulation of the florigens in an abscisic acid- and photoperiod-dependent manner, so that early flowering only occurs under long days. Along with the florigens, the floral integrator SUPPRESSOR OF OVEREXPRESSION OF CONSTANS1 is also up-regulated in a similar fashion and contributes to the activation of TSF. The DE response was recovered under short days in the absence of the floral repressor SHORT VEGETATIVE PHASE or in GI-overexpressing plants. Our data reveal a key role for GI in connecting photoperiodic cues and environmental stress independently from the central FT/TSF activator CONSTANS. This mechanism explains how environmental cues may act upon the florigen genes in a photoperiodically controlled manner, thus enabling plastic flowering responses.

  5. Overexpression of guanylate cyclase activating protein 2 in rod photoreceptors in vivo leads to morphological changes at the synaptic ribbon.

    Directory of Open Access Journals (Sweden)

    Natalia López-del Hoyo

    Full Text Available Guanylate cyclase activating proteins are EF-hand containing proteins that confer calcium sensitivity to retinal guanylate cyclase at the outer segment discs of photoreceptor cells. By making the rate of cGMP synthesis dependent on the free intracellular calcium levels set by illumination, GCAPs play a fundamental role in the recovery of the light response and light adaptation. The main isoforms GCAP1 and GCAP2 also localize to the synaptic terminal, where their function is not known. Based on the reported interaction of GCAP2 with Ribeye, the major component of synaptic ribbons, it was proposed that GCAP2 could mediate the synaptic ribbon dynamic changes that happen in response to light. We here present a thorough ultrastructural analysis of rod synaptic terminals in loss-of-function (GCAP1/GCAP2 double knockout and gain-of-function (transgenic overexpression mouse models of GCAP2. Rod synaptic ribbons in GCAPs-/- mice did not differ from wildtype ribbons when mice were raised in constant darkness, indicating that GCAPs are not required for ribbon early assembly or maturation. Transgenic overexpression of GCAP2 in rods led to a shortening of synaptic ribbons, and to a higher than normal percentage of club-shaped and spherical ribbon morphologies. Restoration of GCAP2 expression in the GCAPs-/- background (GCAP2 expression in the absence of endogenous GCAP1 had the striking result of shortening ribbon length to a much higher degree than overexpression of GCAP2 in the wildtype background, as well as reducing the thickness of the outer plexiform layer without affecting the number of rod photoreceptor cells. These results indicate that preservation of the GCAP1 to GCAP2 relative levels is relevant for maintaining the integrity of the synaptic terminal. Our demonstration of GCAP2 immunolocalization at synaptic ribbons at the ultrastructural level would support a role of GCAPs at mediating the effect of light on morphological remodeling changes of

  6. Tumor Budding, uPA, and PAI-1 in Colorectal Cancer: Update of a Prospective Study.

    Science.gov (United States)

    Märkl, Bruno; Hardt, Jochen; Franz, Simon; Schaller, Tina; Schenkirsch, Gerhard; Kriening, Bernadette; Hoffmann, Reinhard; Rüth, Stefan

    2017-01-01

    Aims. The prognostic role of the proteases uPA and PAI-1, as well as tumor budding, in colon cancer, has been investigated previously. Methods. We provide 6-year follow-up data and results of the validation set. The initial test set and validation set consisted of 55 colon cancers and 68 colorectal cancers, respectively. Tissue samples were analyzed for uPA and PAI-1 using a commercially available Enzyme-Linked Immunosorbent Assay (ELISA). Tumor budding was analyzed on cytokeratin-stained slides. Survival analyses were performed using cut-offs that were determined previously. Results. uPA was not prognostic for outcome. PAI-1 showed a trend towards reduced cancer specific survival in PAI-1 high-grade cases (68 versus 83 months; P = 0.091). The combination of high-grade PAI-1 and tumor budding was associated with significantly reduced cancer specific survival (60 versus 83 months; P = 0.021). After pooling the data from both sets, multivariate analyses revealed that the factors pN-stage, V-stage, and a combination of tumor budding and PAI-1 were independently prognostic for the association with distant metastases. Conclusions. A synergistic adverse effect of PAI-1 and tumor budding in uni- and multivariable analyses was found. PAI-1 could serve as a target for anticancer therapy.

  7. Overexpression of EB1 in human esophageal squamous cell carcinoma (ESCC) may promote cellular growth by activating beta-catenin/TCF pathway.

    Science.gov (United States)

    Wang, Yihua; Zhou, Xiaobo; Zhu, Hongxia; Liu, Shuang; Zhou, Cuiqi; Zhang, Guo; Xue, Liyan; Lu, Ning; Quan, Lanping; Bai, Jinfeng; Zhan, Qimin; Xu, Ningzhi

    2005-10-01

    Esophageal squamous cell carcinoma (ESCC) has a multifactorial etiology involving environmental and/or genetic factors. End-binding protein 1 (EB1), which was cloned as an interacting partner of the adenomatous polyposis coli (APC) tumor suppressor protein, was previously found overexpressed in ESCC. However, the precise role of EB1 in the development of this malignancy has not yet been elucidated. In this study, we analysed freshly resected ESCC specimens and demonstrated that EB1 was overexpressed in approximately 63% of tumor samples compared to matched normal tissue. We report that overexpression of EB1 in the ESCC line EC9706 significantly promotes cell growth, whereas suppression of EB1 protein level by RNA interference significantly inhibited growth of esophageal tumor cells. In addition, EB1 overexpression induced nuclear accumulation of beta-catenin and promoted the transcriptional activity of beta-catenin/T-cell factor (TCF). These effects were partially or completely abolished by coexpression of APC or DeltaN TCF4, respectively. Also, we found that EB1 affected the interaction between beta-catenin and APC. Furthermore, EB1 overexpression was correlated with cytoplasmic/nuclear accumulation of beta-catenin in primary human ESCC. Taken together, these results support the novel hypothesis that EB1 overexpression may play a role in the development of ESCC by affecting APC function and activating the beta-catenin/TCF pathway.

  8. Unsupervised learning human's activities by overexpressed recognized non-speech sounds

    OpenAIRE

    2013-01-01

    Human activity and environment produces sounds such as, at home, the noise produced by water, cough, or television. These sounds can be used to determine the activity in the environment. The objective is to monitor a person's activity or determine his environment using a single low cost microphone by sound analysis. The purpose is to adapt programs to the activity or environment or detect abnormal situations. Some patterns of over expressed repeatedly in the sequences of recognized sounds int...

  9. Neuroprotection by urokinase plasminogen activator in the hippocampus.

    Science.gov (United States)

    Cho, Eunsil; Lee, Kyung Jin; Seo, Jung-Woo; Byun, Catherine Jeonghae; Chung, Sun-Ju; Suh, Dae Chul; Carmeliet, Peter; Koh, Jae-Young; Kim, Jong S; Lee, Joo-Yong

    2012-04-01

    Tissue plasminogen activator (tPA) and urokinase plasminogen activator (uPA), which are both used for thrombolytic treatment of acute ischemic stroke, are serine proteases that convert plasminogen to active plasmin. Although recent experimental evidences have raised controversy about the neurotoxic versus neuroprotective roles of tPA in acute brain injury, uPA remains unexplored in this context. In this study, we evaluated the effect of uPA on neuronal death in the hippocampus of mice after kainate-induced seizures. In the normal brain, uPA was localized to both nuclei and cytosol of neurons. Following severe kainate-induced seizures, uPA completely disappeared in degenerating neurons, whereas uPA-expressing astrocytes substantially increased, suggesting reactive astrogliosis. uPA-knockout mice were more vulnerable to kainate-induced neuronal death than wild-type mice. Consistent with this, inhibition of uPA by intracerebral injection of the uPA inhibitor UK122 increased the level of neuronal death. In contrast, prior administration of recombinant uPA significantly attenuated neuronal death. Collectively, these results indicate that uPA renders neurons resistant to kainate-induced excitotoxicity. Moreover, recombinant uPA suppressed cell death in primary cultures of hippocampal neurons exposed to H2O2, zinc, or various excitotoxins, suggesting that uPA protects against neuronal injuries mediated by the glutamate receptor, or by oxidation- or zinc-induced death signaling pathways. Considering that tPA may facilitate neurodegeneration in acute brain injury, we suggest that uPA, as a neuroprotectant, might be beneficial for the treatment of acute brain injuries such as ischemic stroke.

  10. Cloning, Overexpression, and Characterization of a Metagenome-Derived Phytase with Optimal Activity at Low pH.

    Science.gov (United States)

    Tan, Hao; Wu, Xiang; Xie, Liyuan; Huang, Zhongqian; Gan, Bingcheng; Peng, Weihong

    2015-06-01

    A phytase gene was identified in a publicly available metagenome derived from subsurface groundwater, which was deduced to encode for a protein of the histidine acid phosphatase (HAP) family. The nucleotide sequence of the phytase gene was chemically synthesized and cloned, in order to further overexpress the phytase in Escherichia coli. Purified protein of the recombinant phytase demonstrated an activity for phytic acid of 298 ± 17 μmol P/min/mg, at the pH optimum of 2.0 with the temperature of 37 °C. Interestingly, the pH optimum of this phytase is much lower in comparison with most HAP phytases known to date. It suggests that the phytase could possess improved adaptability to the low pH condition caused by the gastric acid in livestock and poultry stomachs.

  11. Bacterial endotoxin enhances colorectal cancer cell adhesion and invasion through TLR-4 and NF-kappaB-dependent activation of the urokinase plasminogen activator system.

    LENUS (Irish Health Repository)

    Killeen, S D

    2009-05-19

    Perioperative exposure to lipopolysaccharide (LPS) is associated with accelerated metastatic colorectal tumour growth. LPS directly affects cells through Toll-like receptor 4 (TLR-4) and the transcription factor NF-kappaB. The urokinase plasminogen activator (u-PA) system is intimately implicated in tumour cell extracellular matrix (ECM) interactions fundamental to tumour progression. Thus we sought to determine if LPS directly induces accelerated tumour cell ECM adhesion and invasion through activation of the u-PA system and to elucidate the cellular pathways involved. Human colorectal tumour cell lines were stimulated with LPS. u-PA concentration, u-PA activity, active u-PA, surface urokinase plasminogen activator receptor (u-PAR) and TLR-4 expression were assessed by ELISA, colorimetric assay, western blot analysis and flow cytometry respectively. In vitro tumour cell vitronectin adhesion and ECM invasion were analysed by vitronectin adhesion assay and ECM invasion chambers. u-PA and u-PAR function was inhibited with anti u-PA antibodies or the selective u-PA inhibitors amiloride or WXC-340, TLR-4 by TLR-4-blocking antibodies and NF-kappaB by the selective NF-kappaB inhibitor SN-50. LPS upregulates u-PA and u-PAR in a dose-dependent manner, enhancing in vitro tumour cell vitronectin adhesion and ECM invasion by >40% (P<0.01). These effects were ameliorated by u-PA and u-PAR inhibition. LPS activates NF-kappaB through TLR-4. TLR-4 and NF-kappaB inhibition ameliorated LPS-enhanced u-PA and u-PAR expression, tumour cell vitronectin adhesion and ECM invasion. LPS promotes tumour cell ECM adhesion and invasion through activation of the u-PA system in a TLR-4- and NF-kappaB-dependent manner.

  12. Transgenic medaka that overexpress growth hormone have a skin color that does not indicate the activation or inhibition of somatolactin-α signal.

    Science.gov (United States)

    Komine, Ritsuko; Nishimaki, Toshiyuki; Kimura, Tetsuaki; Oota, Hiroki; Naruse, Kiyoshi; Homma, Noriko; Fukamachi, Shoji

    2016-06-10

    Teleosts have two paralogous growth-hormone receptors (GHRs). In vitro studies demonstrated that both receptors bind to and transmit the signal of the growth hormone (GH). However, one of the GHRs (GHR1) was shown to bind more strongly to somatolactin-α (SLα), a fish-specific peptide hormone that is closely related to GH, and is, therefore, termed somatolactin receptor (SLR). In this study, we questioned whether the dual binding of GHR1/SLR causes a crosstalk (reciprocal activation or inhibition) between GH and SLα signals in vivo. For this purpose, we newly established a transgenic medaka that overexpresses GH (Actb-GH:GFP) and assessed its phenotype. The body weight of these transgenic medaka is about twice that of wild-type fish, showing that functional GH was successfully overexpressed in Actb-GH:GFP fish. The transgenic medaka, especially female fish, showed severe infertility, which was a common side effect in GH transgenesis. The skin color, which reflects the effects of SLα most conspicuously in medaka, was similar to that of neither the SLα-overexpressing nor the SLα-deficient medaka, indicating that GH overexpression does not enhance or suppress the SLα signal. We also verified that a transgenic medaka that overexpressed SLα grew and reproduced normally. Therefore, regardless of the in vitro binding relationships, the GH and SLα signals seem not to crosstalk significantly in vivo even when these hormones are overexpressed.

  13. EXPRESSION AND SIGNIFICANCE OF UROKINASE-TYPE PLASMINOGEN ACTIVATOR IN BREAST CANCER

    Institute of Scientific and Technical Information of China (English)

    XIAO Jiping; ZHANG Guangde; XIA Wenhua; CHENG Deji

    1999-01-01

    Objective: To study the expression and clinical significance of urokinase-type plasminogen activator (uPA) in breast cancer. Methods: Applying streptavidin-biotin complex (SABC) immunohistochemical technique, expression of uPA was studied in 100 patients with primary breast cancer. Results: There were 55 patients with high uPA expression, and 45 with lower expression. There was significant correlation between uPA expression and TNM stage, lymph node status, and the tumor size. Neither age, menopausal status, nor ER status was significantly related with level of uPA expression. The patients with high expression of uPA had significantly shorter disease-free survival (DFS)and overall survival (OS) than did those with low expression of uPA. Univariate analysis showed that uPA as a prognostic factor was of similar magnitude to lymph node status and TNM stage, but stronger than that of ER status and tumor size. UPA was an independent prognostic factor affecting disease-free survival and overall survival. Conclusion: uPA appears to be a strong and independent biologic marker for predicting prognosis of breast cancer.

  14. Common TNF-α, IL-1β, PAI-1, uPA, CD14 and TLR4 polymorphisms are not associated with disease severity or outcome from Gram negative sepsis

    Directory of Open Access Journals (Sweden)

    Eugen-Olsen Jesper

    2007-09-01

    Full Text Available Abstract Background Several studies have investigated single nucleotide polymorphisms (SNPs in candidate genes associated with sepsis and septic shock with conflicting results. Only few studies have combined the analysis of multiple SNPs in the same population. Methods Clinical data and DNA from consecutive adult patients with culture proven Gram negative bacteremia admitted to a Danish hospital between 2000 and 2002. Analysis for commonly described SNPs of tumor necrosis-α, (TNF-α, interleukin-1β (IL-1β, plasminogen activator-1 (PAI-1, urokinase plasminogen activator (uPA, CD14 and toll-like receptor 4 (TLR4 was done. Results Of 319 adults, 74% had sepsis, 19% had severe sepsis and 7% were in septic shock. No correlation between severity or outcome of sepsis was observed for the analyzed SNPs of TNF-α, IL-1β, PAI-1, uPA, CD14 or TLR-4. In multivariate Cox proportional hazard regression analysis, increasing age, polymicrobial infection and haemoglobin levels were associated with in-hospital mortality. Conclusion We did not find any association between TNF-α, IL-1β, PAI-1, uPA, CD14 and TLR4 polymorphisms and outcome of Gram negative sepsis. Other host factors appear to be more important than the genotypes studied here in determining the severity and outcome of Gram negative sepsis.

  15. Optimized immunohistochemistry in combination with image analysis: a reliable alternative to quantitative ELISA determination of uPA and PAI-1 for routine risk group discrimination in breast cancer.

    Science.gov (United States)

    Lang, D S; Heilenkötter, U; Schumm, W; Behrens, O; Simon, R; Vollmer, E; Goldmann, T

    2013-10-01

    The determination of the invasion markers urokinase-type plasminogen activator (uPA) and plasminogen activator inhibitor-1 (PAI-1) has further improved the possibilities for individualized therapy of breast cancer. To date, quantitative measurement by ELISA, that needs large amounts of fresh, frozen material, is the only standardized procedure for diagnostic purposes. Therefore, the aim of this study was the establishment of a reliable alternative method based on immunohistochemistry (IHC) and image analysis requiring only small amounts of fixed tumor tissue. Protein expression of uPA and PAI-1 was analyzed in HOPE-fixed tumor samples using tissue microarrays (TMAs) and semiquantitative image analysis. The results of both methods were significantly correlated and risk assessment showed an overall concordance of 78% (83/107; high- and low-risk) and of 94% (74/79) regarding only high-risk patients. The data demonstrate that optimized IHC in combination with image analysis can provide adequate clinical significance compared to ELISA-derived determination of uPA and PAI-1.

  16. Overexpression of hepatic plasminogen activator inhibitor type 1 mRNA in rabbits with fatty liver

    Institute of Scientific and Technical Information of China (English)

    Jian-Gao Fan; Liang-Hua Chen; Zheng-Jie Xu; Min-De Zeng

    2001-01-01

    @@ INTRODUCTION Plasminogen activator inhibitor type 1 ( PAI-I ), an approximately Mr 50000 glycoprotein, is the major physiological inhibitor of plasminogen activators. It is not only the priming factor for atherosclerosis and coronary thrombosis[1-3] , but also participates in the genesis of chronic hepatitis and liver fibrosis[4-11] . However, there has been no available report yet about the research of hepatic PAl-1 gene expression in hyperlipidemia and fatty liver. The present study aimed to explore the change of hepatic PAl-1 mRNA and its plasma activity by means of animal model.

  17. RKIP phosphorylation-dependent ERK1 activation stimulates adipogenic lipid accumulation in 3T3-L1 preadipocytes overexpressing LC3.

    Science.gov (United States)

    Hahm, Jong Ryeal; Ahmed, Mahmoud; Kim, Deok Ryong

    2016-09-01

    3T3-L1 preadipocytes undergo adipogenesis in response to treatment with dexamethaxone, 1-methyl-3-isobutylxanthine, and insulin (DMI) through activation of several adipogenic transcription factors. Many autophagy-related proteins are also highly activated in the earlier stages of adipogenesis, and the LC3 conjugation system is required for formation of lipid droplets. Here, we investigated the effect of overexpression of green fluorescent protein (GFP)-LC3 fusion protein on adipogenesis. Overexpression of GFP-LC3 in 3T3-L1 preadipocytes using poly-l-lysine-assisted adenoviral GFP-LC3 transduction was sufficient to produce intracellular lipid droplets. Indeed, GFP-LC3 overexpression stimulated expression of some adipogenic transcription factors (e.g., C/EBPα or β, PPARγ, SREBP2). In particular, SREBP2 was highly activated in preadipocytes transfected with adenoviral GFP-LC3. Also, phosphorylation of Raf kinase inhibitory protein (RKIP) at serine 153, consequently stimulating extracellular-signal regulated kinase (ERK)1 activity, was significantly increased during adipogenesis induced by either poly-l-lysine-assisted adenoviral GFP-LC3 transduction or culture in the presence of dexamethasone, 1-methyl-3-isobutylxanthine, and insulin. Furthermore, RKIP knockdown promoted ERK1 and PPARγ activation, and significantly increased the intracellular accumulation of triacylglycerides in DMI-induced adipogenesis. In conclusion, GFP-LC3 overexpression in 3T3-L1 preadipocytes stimulates adipocyte differentiation via direct modulation of RKIP-dependent ERK1 activity.

  18. Overexpression of Id1 in transgenic mice promotes mammary basal stem cell activity and breast tumorigenesis.

    Science.gov (United States)

    Shin, Dong-Hui; Park, Ji-Hye; Lee, Jeong-Yeon; Won, Hee-Young; Jang, Ki-Seok; Min, Kyueng-Whan; Jang, Si-Hyong; Woo, Jong-Kyu; Oh, Seung Hyun; Kong, Gu

    2015-07-10

    Inhibitor of differentiation/DNA binding (Id)1 is a crucial regulator of mammary development and breast cancer progression. However, its effect on stemness and tumorigenesis in mammary epithelial cells remains undefined. Herein, we demonstrate that Id1 induces mammary tumorigenesis by increasing normal and malignant mammary stem cell (MaSC) activities in transgenic mice. MaSC-enriched basal cell expansion and increased self-renewal and in vivo regenerative capacity of MaSCs are observed in the mammary glands of MMTV-Id1 transgenic mice. Furthermore, MMTV-Id1 mice develop ductal hyperplasia and mammary tumors with highly expressed basal markers. Id1 also increases breast cancer stem cell (CSC) population and activity in human breast cancer lines. Moreover, the effects of Id1 on normal and malignant stem cell activities are mediated by the Wnt/c-Myc pathway. Collectively, these findings provide in vivo genetic evidence of Id1 functions as an oncogene in breast cancer and indicate that Id1 regulates mammary basal stem cells by activating the Wnt/c-Myc pathway, thereby contributing to breast tumor development.

  19. Expression and clinical significance of Hpa and uPA in thyroid carcinoma%Hpa、uPA 在分化型甲状腺癌组织中表达的临床意义

    Institute of Scientific and Technical Information of China (English)

    李建业; 鲁凯; 姚壮凯; 耿强; 张哲雄; 孙志超

    2015-01-01

    Objective To study the relationship between heparanase( Hpa) , urokinase type plasminogen activator( uPA) expression and lymph node metastasis in thyroid carcinoma.Methods Immunohistochemieal SP method was used to analyze the expression of Hpa and uPA in 113 cases of thyroid carcinoma and 134 cases of be-nign thyroid nodules.The expression of Hpa and uPA in thyroid carcinoma and its clinical significance were ana-lyzed.Results The positive expression rate of Hpa and uPA in thyroid carcinoma and benign nodular thyroid tis-sue were 82.30%,16.42%and 89.38%, 11.19%.The positive expression rate of Hpa and uPA in carcinoma tissues with lymph metastasis and without metastasis were 93.94%,100% and 65.96%,74.47%.Expression of Hpa and uPA in thyroid carcinoma group was significantly higher than that of benign thyroid nodules group( P<0.001) .The rate of positive expression in lymph metastatic tissues were significantly higher than those in tissue without metastasis( P<0.001) .Hpa and uPA expression in thyroid carcinoma tissues was positively correlated( r=0.437, P=0.021).Conclusion The expression of Hpa and uPA is closely related with the occurrence and metastasis of thyroid carcinoma.%目的:研究乙酰肝素酶( heparanase,Hpa)、尿激酶纤溶酶原激活剂( urokinase type plasmino-gen activator,uPA)在甲状腺癌组织中的表达与淋巴结转移的关系。方法采用免疫组化SP法检测113例甲状腺癌及134例良性甲状腺结节组织中Hpa、uPA蛋白的表达情况,分析Hpa、uPA蛋白在甲状腺癌中表达及其临床意义。结果 Hpa、uPA在甲状腺癌及良性甲状腺结节组织中表达阳性率分别为82.30%、89.38%和16.42%、11.19%,甲状腺癌组织中Hpa、uPA的表达高于良性甲状腺结节(P<0.001)。在甲状腺癌有、无淋巴结转移组Hpa、uPA蛋白表达阳性率分别93.94%、100%和65.96%、74.47%,甲状腺癌组织中有周围淋巴结转移组Hpa、uPA的表达高于

  20. Overexpression and enhanced specific activity of aldoketo reductases (AKR1B1 & AKR1B10) in human breast cancers.

    Science.gov (United States)

    Reddy, K Ashok; Kumar, P Uday; Srinivasulu, M; Triveni, B; Sharada, K; Ismail, Ayesha; Reddy, G Bhanuprakash

    2017-02-01

    The incidence of breast cancer in India is on the rise and is rapidly becoming the primary cancer in Indian women. The aldoketo reductase (AKR) family has more than 190 proteins including aldose reductase (AKR1B1) and aldose reductase like protein (AKR1B10). Apart from liver cancer, the status of AKR1B1 and AKR1B10 with respect to their expression and activity has not been reported in other human cancers. We studied the specific activity and expression of AKR1B1 and AKR1B10 in breast non tumor and tumor tissues and in the blood. Fresh post-surgical breast cancer and non-cancer tissues and blood were collected from the subjects who were admitted for surgical therapy. Malignant, benign and pre-surgical chemotherapy samples were evaluated by histopathology scoring. Expression of AKR1B1 and AKR1B10 was carried out by immunoblotting and immunohistochemistry (IHC) while specific activity was determined spectrophotometrically. The specific activity of AKR1B1 was significantly higher in red blood cells (RBC) in all three grades of primary surgical and post-chemotherapy samples. Specific activity of both AKR1B1 and AKR1B10 increased in tumor samples compared to their corresponding non tumor samples (primary surgical and post-chemotherapy). Immunoblotting and IHC data also indicated overexpression of AKR1B1 in all grades of tumors compared to their corresponding non tumor samples. There was no change in the specific activity of AKR1B1 in benign samples compared to all grades of tumor and non-tumors.

  1. Overexpression of Id1 in transgenic mice promotes mammary basal stem cell activity and breast tumorigenesis

    OpenAIRE

    Shin, Dong-Hui; Park, Ji-Hye; Lee, Jeong-Yeon; Won, Hee-Young; Jang, Ki-Seok; MIN, KYUENG-WHAN; Jang, Si-Hyong; Woo, Jong-Kyu; Oh, Seung Hyun; Kong, Gu

    2015-01-01

    Inhibitor of differentiation/DNA binding (Id)1 is a crucial regulator of mammary development and breast cancer progression. However, its effect on stemness and tumorigenesis in mammary epithelial cells remains undefined. Herein, we demonstrate that Id1 induces mammary tumorigenesis by increasing normal and malignant mammary stem cell (MaSC) activities in transgenic mice. MaSC-enriched basal cell expansion and increased self-renewal and in vivo regenerative capacity of MaSCs are observed in th...

  2. The complex between urokinase (uPA) and its type-1 inhibitor (PAI-1) in pulmonary adenocarcinoma: Relation to prognosis

    DEFF Research Database (Denmark)

    Pappot, Helle; Pedersen, Anders N; Brünner, Nils

    2006-01-01

    In a lung cancer population comprising tumor tissue from 99 pulmonary adenocarcinoma patients, the relationship between tumor tissue level of the complex formed of urokinase (uPA) and its type-1 inhibitor (PAI-1) and survival was studied. The study included patient material previously investigated....... The amounts of uPA-PAI-1 complex measured in pulmonary adenocarcinoma tissue were within the same range as previously reported in breast cancer tissue (0.11-5.74 ng/mg protein). uPA and PAI-1 levels were weakly correlated to the uPA-PAI-1 complex, r = 0.52 and r = 0.47, respectively, and no relation was found...... these interactions and the clinical importance of the tissue levels of uPA, PAI-1 and uPA-PAI-1 complex, the results suggest further exploratory studies of the components in pulmonary adenocarcinomas and other cancers....

  3. The complex between urokinase (uPA) and its type-1 inhibitor (PAI-1) in pulmonary adenocarcinoma

    DEFF Research Database (Denmark)

    Pappot, Helle; Pedersen, Anders N.; Brünner, Nils

    2006-01-01

    In a lung cancer population comprising tumor tissue from 99 pulmonary adenocarcinoma patients, the relationship between tumor tissue level of the complex formed of urokinase (uPA) and its type-1 inhibitor (PAI-1) and survival was studied. The study included patient material previously investigated....... The amounts of uPA-PAI-1 complex measured in pulmonary adenocarcinoma tissue were within the same range as previously reported in breast cancer tissue (0.11-5.74 ng/mg protein). uPA and PAI-1 levels were weakly correlated to the uPA-PAI-1 complex, r = 0.52 and r = 0.47, respectively, and no relation was found...... these interactions and the clinical importance of the tissue levels of uPA, PAI-1 and uPA-PAI-1 complex, the results suggest further exploratory studies of the components in pulmonary adenocarcinomas and other cancers....

  4. Urokinase, urokinase receptor, and plasminogen activator inhibitor-1 expression on podocytes in immunoglobulin A glomerulonephritis

    OpenAIRE

    Lee, Ji-Hye; Oh, Mee-Hye; Park, Jae-seok; Na, Gyoung-Jae; Gil, Hye-Wook; Yang, Jong-Oh; Lee, Eun-Young; Hong, Sae-Yong

    2014-01-01

    Background/Aims The purpose of this study was to investigate the expression of urokinase-type plasminogen activator (uPA), uPA receptor (uPAR), and plasminogen activator inhibitor (PAI)-1 on podocytes in immunoglobulin A (IgA) glomerulonephritis (GN). Methods Renal biopsy specimens from 52 IgA GN patients were deparaffinized and subjected to immunohistochemical staining for uPA, PAI-1, and uPAR. The biopsies were classified into three groups according to the expression of uPA and uPAR on podo...

  5. Process and genes for expression and overexpression of active [FeFe] hydrogenases

    Energy Technology Data Exchange (ETDEWEB)

    Seibert, Michael; King, Paul W; Ghirardi, Maria Lucia; Posewitz, Matthew C; Smolinski, Sharon L

    2014-09-16

    A process for expression of active [FeFe]-hydrogenase in a host organism that does not contain either the structural gene(s) for [FeFe]-hydrogenases and/or homologues for the maturation genes HydE, HydF and HyG, comprising: cloning the structural hydrogenase gene(s) and/or the maturation genes HydE, HydF and HydG from an organisms that contains these genes into expression plasmids; transferring the plasmids into an organism that lacks a native [FeFe]-hydrogenase or that has a disrupted [FeFe]-hydrogenase and culturing it aerobically; and inducing anaerobiosis to provide [FeFe] hydrogenase biosynthesis and H?2#191 production.

  6. Metastin receptor is overexpressed in papillary thyroid cancer and activates MAP kinase in thyroid cancer cells.

    Science.gov (United States)

    Ringel, Matthew D; Hardy, Elena; Bernet, Victor J; Burch, Henry B; Schuppert, Frank; Burman, Kenneth D; Saji, Motoyasu

    2002-05-01

    The development of distant metastasis is the most important predictor of death from thyroid cancer. KiSS-1 is a recently cloned human metastasis suppressor gene whose product, metastin, was recently identified as the endogenous agonist for a novel Gq/11 coupled receptor (metastin receptor). The expression and functional consequences of metastin and the metastin receptor have not been evaluated in thyroid cancer. We measured metastin and metastin receptor mRNA levels in 10 FCs and 13 papillary carcinomas (PCs), 2 benign non-functioning follicular adenomas (FAs), and 11 normal thyroid samples, and evaluated the signaling pathways activated by metastin in ARO thyroid cancer cells that express the metastin receptor endogenously. Paired normal and tumor samples were available for 4 PC and 3 PFC samples. Metastin mRNA was detected in 6/11 normal samples, and 0/2 FA, 2/10 FC, and 9/13 PC samples (p Metastin receptor was not expressed in any normal thyroid or benign FA samples, and was expressed in only a minority (2/10) of FC samples. However, the receptor was expressed in the majority (10/13) of PCs (p = 0.002 for PC vs. normal tissue). Increased levels of metastin receptor were detected in all four PCs compared to adjacent normal tissue. Incubation levels of metastin receptor were detected in all four PCs compared to adjacent normal tissue. Incubation of metastin receptor expressing ARO thyroid cancer cells with metastin resulted in activation of ERK, but not Akt. Taken together, these data suggest a potential role for metastin and/or metastin receptors in modulating the biological behavior of thyroid cancers.

  7. Effect of gene modified mesenchymal stem cells overexpression human receptor activity modified protein 1 on inflammation and cardiac repair in a rabbit model of myocardial infarction

    Institute of Scientific and Technical Information of China (English)

    赵然尊

    2012-01-01

    Objective To investigate the effect of mesenchymal stem cells(MSCs) overexpressing human receptor activity modified protein 1(hRAMP1) by adenovirus vector on infarction related inflammation and cardiac repair in a rabbit model of myocardial infarction(MI)

  8. Engagement of overexpressed Her2 with GEP100 induces autonomous invasive activities and provides a biomarker for metastases of lung adenocarcinoma.

    Directory of Open Access Journals (Sweden)

    Toshi Menju

    Full Text Available Overexpression of Her2/ErbB2/Neu in cancer is often correlated with recurrent distant metastasis, although the mechanism still remains largely elusive. We have previously shown that EGFR, when tyrosine-phosphorylated, binds to GEP100/BRAG2 to activate Arf6, which induces cancer invasion and metastasis. We now show that overexpressed Her2 in lung adenocarcinoma cells also employs GEP100. Like EGFR-GEP100 binding, this association is primarily mediated by the pleckstrin homology (PH domain of GEP100 and Tyr1139/Tyr1196 of Her2. Tyr1139/Tyr1196 are autonomously phosphorylated, when Her2 is overexpressed. Accordingly, invasive activities mediated by the Her2-GEP100 pathway are not dependent on external factors. Blocking Her2-GEP100 binding, as well as its signaling pathway all inhibit cancer invasive activities. Moreover, our clinical study indicates that co-overexpression of Her2 with GEP100 in primary lung adenocarcinomas of patients is correlated with the presence of their node-metastasis with a statistical significance. Since the GEP100 PH domain interacts with both Her2 and EGFR, targeting this domain may provide novel cancer therapeutics.

  9. Overexpression of constitutively active BMP-receptor-IB in mouse skin causes an ichthyosis-vulgaris-like disease.

    Science.gov (United States)

    Yu, Xueyan; Espinoza-Lewis, Ramón A; Sun, Cheng; Lin, Lisong; He, Fenglei; Xiong, Wei; Yang, Jing; Wang, Alun; Chen, Yiping

    2010-12-01

    The skin is the outer layer of protection against the environment. The development and formation of the skin is regulated by several genetic cascades including the bone morphogenetic protein (BMP) signaling pathway, which has been suggested to play an important role during embryonic organ development. Several skin defects and diseases are caused by genetic mutations or disorders. Ichthyosis is a common genetic skin disorder characterized by dry scaly skin. Loss-of-function mutations in the filaggrin (FLG) gene have been identified as the cause of the ichthyosis vulgaris (IV) phenotype; however, the direct regulation of filaggrin expression in vivo is unknown. We present evidence that BMP signaling regulates filaggrin expression in the epidermis. Mice expressing a constitutively active form of BMP-receptor-IB in the developing epidermis exhibit a phenotype resembling IV in humans, including dry flaky skin, compact hyperkeratosis, and an attenuated granular layer associated with a significantly downregulated expression of filaggrin. Regulation of filaggrin expression by BMP signaling has been further confirmed by the application of exogenous BMP2 in skin explants and by a transgenic model overexpressing Noggin in the epidermis. Our results demonstrate that aberrant BMP signaling in the epidermis causes overproliferation and hyperkeratinization, leading to an IV-like skin disease.

  10. SIRT1 overexpression antagonizes cellular senescence with activated ERK/S6k1 signaling in human diploid fibroblasts.

    Directory of Open Access Journals (Sweden)

    Jing Huang

    Full Text Available Sir2, a NAD-dependent deacetylase, modulates lifespan in yeasts, worms and flies. The SIRT1, mammalian homologue of Sir2, regulates signaling for favoring survival in stress. But whether SIRT1 has the function to influence cell viability and senescence under non-stressed conditions in human diploid fibroblasts is far from unknown. Our data showed that enforced SIRT1 expression promoted cell proliferation and antagonized cellular senescence with the characteristic features of delayed Senescence-Associated beta-galactosidase (SA-beta-gal staining, reduced Senescence-Associated Heterochromatic Foci (SAHF formation and G1 phase arrest, increased cell growth rate and extended cellular lifespan in human fibroblasts, while dominant-negative SIRT1 allele (H363Y did not significantly affect cell growth and senescence but displayed a bit decreased lifespan. Western blot results showed that SIRT1 reduced the expression of p16(INK4A and promoted phosphorylation of Rb. Our data also exposed that overexpression of SIRT1 was accompanied by enhanced activation of ERK and S6K1 signaling. These effects were mimicked in both WI38 cells and 2BS cells by concentration-dependent resveratrol, a SIRT1 activator. It was noted that treatment of SIRT1-.transfected cells with Rapamycin, a mTOR inhibitor, reduced the phosphorylation of S6K1 and the expression of Id1, implying that SIRT1-induced phosphorylation of S6K1 may be partly for the decreased expression of p16(INK4A and promoted phosphorylation of Rb in 2BS. It was also observed that the expression of SIRT1 and phosphorylation of ERK and S6K1 was declined in senescent 2BS. These findings suggested that SIRT1-promoted cell proliferation and antagonized cellular senescence in human diploid fibroblasts may be, in part, via the activation of ERK/ S6K1 signaling.

  11. Peroxisome proliferator-activated receptor-gamma agonists suppress tissue factor overexpression in rat balloon injury model with paclitaxel infusion.

    Directory of Open Access Journals (Sweden)

    Jun-Bean Park

    Full Text Available The role and underlying mechanisms of rosiglitazone, a peroxisome proliferator-activated receptor-gamma (PPAR-γ agonist, on myocardial infarction are poorly understood. We investigated the effects of this PPAR-γ agonist on the expression of tissue factor (TF, a primary molecule for thrombosis, and elucidated its underlying mechanisms. The PPAR-γ agonist inhibited TF expression in response to TNF-α in human umbilical vein endothelial cells, human monocytic leukemia cell line, and human umbilical arterial smooth muscle cells. The overexpression of TF was mediated by increased phosphorylation of mitogen-activated protein kinase (MAPK, which was blocked by the PPAR-γ agonist. The effective MAPK differed depending on each cell type. Luciferase and ChIP assays showed that transcription factor, activator protein-1 (AP-1, was a pivotal target of the PPAR-γ agonist to lower TF transcription. Intriguingly, two main drugs for drug-eluting stent, paclitaxel or rapamycin, significantly exaggerated thrombin-induced TF expression, which was also effectively blocked by the PPAR-γ agonist in all cell types. This PPAR-γ agonist did not impair TF pathway inhibitor (TFPI in three cell types. In rat balloon injury model (Sprague-Dawley rats, n = 10/group with continuous paclitaxel infusion, the PPAR-γ agonist attenuated TF expression by 70±5% (n = 4; P<0.0001 in injured vasculature. Taken together, rosiglitazone reduced TF expression in three critical cell types involved in vascular thrombus formation via MAPK and AP-1 inhibitions. Also, this PPAR-γ agonist reversed the paclitaxel-induced aggravation of TF expression, which suggests a possibility that the benefits might outweigh its risks in a group of patients with paclitaxel-eluting stent implanted.

  12. Over-expression of rice leucine-rich repeat protein results in activation of defense response, thereby enhancing resistance to bacterial soft rot in Chinese cabbage.

    Science.gov (United States)

    Park, Young Ho; Choi, Changhyun; Park, Eun Mi; Kim, Hyo Sun; Park, Hong Jae; Bae, Shin Cheol; Ahn, Ilpyung; Kim, Min Gab; Park, Sang Ryeol; Hwang, Duk-Ju

    2012-10-01

    Pectobacterium carotovorum subsp. carotovorum causes soft rot disease in various plants, including Chinese cabbage. The simple extracellular leucine-rich repeat (eLRR) domain proteins have been implicated in disease resistance. Rice leucine-rich repeat protein (OsLRP), a rice simple eLRR domain protein, is induced by pathogens, phytohormones, and salt. To see whether OsLRP enhances disease resistance to bacterial soft rot, OsLRP was introduced into Chinese cabbage by Agrobacterium-mediated transformation. Two independent transgenic lines over-expressing OsLRP were generated and further analyzed. Transgenic lines over-expressing OsLRP showed enhanced disease resistance to bacterial soft rot compared to non-transgenic control. Bacterial growth was retarded in transgenic lines over-expressing OsLRP compared to non-transgenic controls. We propose that OsLRP confers enhanced resistance to bacterial soft rot. Monitoring expression of defense-associated genes in transgenic lines over-expressing OsLRP, two different glucanases and Brassica rapa polygalacturonase inhibiting protein 2, PDF1 were constitutively activated in transgenic lines compared to non-transgenic control. Taken together, heterologous expression of OsLRP results in the activation of defense response and enhanced resistance to bacterial soft rot.

  13. Cardiac-specific overexpression of catalase prevents diabetes-induced pathological changes by inhibiting NF-κB signaling activation in the heart.

    Science.gov (United States)

    Cong, Weitao; Ruan, Dandan; Xuan, Yuanhu; Niu, Chao; Tao, Youli; Wang, Yang; Zhan, Kungao; Cai, Lu; Jin, Litai; Tan, Yi

    2015-12-01

    Catalase is an antioxidant enzyme that specifically catabolizes hydrogen peroxide (H2O2). Overexpression of catalase via a heart-specific promoter (CAT-TG) was reported to reduce diabetes-induced accumulation of reactive oxygen species (ROS) and further prevent diabetes-induced pathological abnormalities, including cardiac structural derangement and left ventricular abnormity in mice. However, the mechanism by which catalase overexpression protects heart function remains unclear. This study found that activation of a ROS-dependent NF-κB signaling pathway was downregulated in hearts of diabetic mice overexpressing catalase. In addition, catalase overexpression inhibited the significant increase in nitration levels of key enzymes involved in energy metabolism, including α-oxoglutarate dehydrogenase E1 component (α-KGD) and ATP synthase α and β subunits (ATP-α and ATP-β). To assess the effects of the NF-κB pathway activation on heart function, Bay11-7082, an inhibitor of the NF-κB signaling pathway, was injected into diabetic mice, protecting mice against the development of cardiac damage and increased nitrative modifications of key enzymes involved in energy metabolism. In conclusion, these findings demonstrated that catalase protects mouse hearts against diabetic cardiomyopathy, partially by suppressing NF-κB-dependent inflammatory responses and associated protein nitration.

  14. Aberrant glomerular filtration of urokinase-type plasminogen activator in nephrotic syndrome leads to amiloride-sensitive plasminogen activation in urine

    DEFF Research Database (Denmark)

    Staehr, Mette; Buhl, Kristian B; Andersen, René F

    2015-01-01

    (uPA) in vitro. It was hypothesized that uPA is abnormally filtered to pre-urine and is inhibited in urine by amiloride in nephrotic syndrome. This was tested by determination of Na+-balance, uPA protein and activity and amiloride concentration in urine from rats with puromycin aminonucleoside (PAN......In nephrotic syndrome, aberrant glomerular filtration of plasminogen and conversion to active plasmin in pre-urine is thought to activate proteolytically ENaC and contribute to sodium retention and edema. The ENaC blocker amiloride is an off-target inhibitor of urokinase-type plasminogen activator......) induced nephrotic syndrome. Urine samples from 6 adult and 18 pediatric patients with nephrotic syndrome were analyzed for uPA activity and protein. PAN-treatment induced significant proteinuria in rats which coincided with increased urine uPA protein and activity, increased urine protease activity...

  15. Osmium (VI) complexes of the 3', 5'-dinucleoside monophosphates, ApU and UpA.

    Science.gov (United States)

    Daniel, F B; Behrman, E J

    1976-02-10

    The dinucleoside monophosphates, ApU and UpA, react with potassium osmate (VI) and 2,2'-bipyridyl to form the corresponding oxo-osmium (VI) bipyridyl sugar ester in which the osmate group is bonded to the terminal 2',3'-glycol. Osmium (VIII) tetroxide and 2,2'-bipyridyl react with the dinucleosides to form the corresponding oxo-osmium (VI) bipyridyl heterocyclic esters which result from addition of the tetroxide to the 5,6-double bond of the uracil residue. Although capable of transesterification reactions, these heterocyclic esters are exceptionally stable toward exchange reactions in solution. No apparent exchange was observed after 1 month. This reaction thus seems promising for single-site osmium labeling in polynucleotides.

  16. Overexpression of SDF-1 activates the NF-κB pathway to induce epithelial to mesenchymal transition and cancer stem cell-like phenotypes of breast cancer cells.

    Science.gov (United States)

    Kong, Lingxin; Guo, Sufen; Liu, Chunfeng; Zhao, Yiling; Feng, Chong; Liu, Yunshuang; Wang, Tao; Li, Caijuan

    2016-03-01

    The formation of EMT and EMT-induced CSC-like phenotype is crucial for the metastasis of tumor cells. The stromal cell-derived factor-1 (SDF-1) is upregulated in various human carcinomas, which is closely associated with proliferation, migration, invasion and prognosis of malignancies. However, limited attention has been directed towards the effect of SDF-1 on epithelial to mesenchymal transition (EMT) or cancer stem cell (CSC)-like phenotype formation in breast cancer cells and the related mechanism. In the present study, we screened MCF-7 cells with low SDF-1 expression level for the purpose of evaluating whether SDF-1 is involved in EMT and CSC-like phenotype formation in MCF-7 cells. The pEGFP-N1-SDF-1 plasmid was transfected into MCF-7 cells, and the stably overexpressed SDF-1 in MCF-7 cells was confirmed by real-time PCR and western blot analysis. Colony formation assay, MTT, wound healing assay and Transwell invasion assay demonstrated that overexpression of SDF-1 significantly boosted the proliferation, migration and invasion of MCF-7 cells compared with parental (PSDF-1 overexpressing MCF-7 cells (PSDF-1 overexpressed MCF-7 cells in comparison with parental (PSDF-1 induced the activation of NF-κB pathway in MCF-7 cells. Conversely, suppressing or silencing p65 expression by antagonist or RNA interference could remarkably increase the expression of E-cadherin in SDF-1 overexpressed MCF-7 cells (PSDF-1 enhanced EMT by activating the NF-κB pathway of MCF-7 cells and further induced the formation of CSC-like phenotypes, ultimately promoting the proliferation and metastasis of MCF-7 cells. Therefore, SDF-1 may further be assessed as a potential target for gene therapy of breast cancer.

  17. Antibody-mediated targeting of the urokinase-type plasminogen activator proteolytic function neutralizes fibrinolysis in vivo

    DEFF Research Database (Denmark)

    Lund, Ida K; Jögi, Annika; Rønø, Birgitte

    2008-01-01

    Urokinase-type plasminogen activator (uPA) plays a central role in tissue remodeling processes. Most of our understanding of the role of uPA in vivo is derived from studies using gene-targeted uPA-deficient mice. To enable in vivo studies on the specific interference with uPA functionality in mouse...... models, we have now developed murine monoclonal antibodies (mAbs) directed against murine uPA by immunization of uPA-deficient mice with the recombinant protein. Guided by enzyme-linked immunosorbent assay, Western blotting, surface plasmon resonance, and enzyme kinetic analyses, we have selected two...

  18. JNK suppression is essential for 17β-Estradiol inhibits prostaglandin E2-Induced uPA and MMP-9 expressions and cell migration in human LoVo colon cancer cells

    Directory of Open Access Journals (Sweden)

    Chen Wei-Kung

    2011-08-01

    Full Text Available Abstract Background Epidemiological studies demonstrate that the incidence and mortality rates of colorectal cancer in women are lower than in men. However, it is unknown if 17β-estradiol treatment is sufficient to inhibit prostaglandin E2 (PGE2-induced cellular motility in human colon cancer cells. Methods We analyzed the protein expression of urokinase plasminogen activator (uPA, tissue plasminogen activator (tPA, matrix metallopeptidases (MMPs, plasminogen activator inhibitor-1 (PAI-1 and tissue inhibitor of metalloproteinases (TIMPs, and the cellular motility in PGE2-stimulated human LoVo cells. 17β-Estradiol and the inhibitors including LY294002 (Akt activation inhibitor, U0126 (ERK1/2 inhibitor, SB203580 (p38 MAPK inhibitor, SP600125 (JNK1/2 inhibitor, QNZ (NFκB inhibitor and ICI 182 780 were further used to explore the inhibitory effects of 17β-estradiol on PGE2-induced LoVo cell motility. Student's t-test was used to analyze the difference between the two groups. Results Upregulation of urokinase plasminogen activator (uPA, tissue plasminogen activator (tPA and matrix metallopeptidases (MMPs is reported to associate with the development of cancer cell mobility, metastasis, and subsequent malignant tumor. After administration of inhibitors including LY294002, U0126, SB203580, SP600125 or QNZ, we found that PGE2 treatment up-regulated uPA and MMP-9 expression via JNK1/2 signaling pathway, thus promoting cellular motility in human LoVo cancer cells. However, PGE2 treatment showed no effects on regulating expression of tPA, MMP-2, plasminogen activator inhibitor-1 (PAI-1, tissue inhibitor of metalloproteinase-1, -2, -3 and -4 (TIMP-1, -2, -3 and -4. We further observed that 17β-estradiol treatment inhibited PGE2-induced uPA, MMP-9 and cellular motility by suppressing activation of JNK1/2 in human LoVo cancer cells. Conclusions Collectively, these results suggest that 17β-estradiol treatment significantly inhibits PGE2-induced motility

  19. Wild-Type N-Ras, Overexpressed in Basal-like Breast Cancer, Promotes Tumor Formation by Inducing IL-8 Secretion via JAK2 Activation

    Directory of Open Access Journals (Sweden)

    Ze-Yi Zheng

    2015-07-01

    Full Text Available Basal-like breast cancers (BLBCs are aggressive, and their drivers are unclear. We have found that wild-type N-RAS is overexpressed in BLBCs but not in other breast cancer subtypes. Repressing N-RAS inhibits transformation and tumor growth, whereas overexpression enhances these processes even in preinvasive BLBC cells. We identified N-Ras-responsive genes, most of which encode chemokines; e.g., IL8. Expression levels of these chemokines and N-RAS in tumors correlate with outcome. N-Ras, but not K-Ras, induces IL-8 by binding and activating the cytoplasmic pool of JAK2; IL-8 then acts on both the cancer cells and stromal fibroblasts. Thus, BLBC progression is promoted by increasing activities of wild-type N-Ras, which mediates autocrine/paracrine signaling that can influence both cancer and stroma cells.

  20. Wild-Type N-Ras, Overexpressed in Basal-like Breast Cancer, Promotes Tumor Formation by Inducing IL-8 Secretion via JAK2 Activation.

    Science.gov (United States)

    Zheng, Ze-Yi; Tian, Lin; Bu, Wen; Fan, Cheng; Gao, Xia; Wang, Hai; Liao, Yi-Hua; Li, Yi; Lewis, Michael T; Edwards, Dean; Zwaka, Thomas P; Hilsenbeck, Susan G; Medina, Daniel; Perou, Charles M; Creighton, Chad J; Zhang, Xiang H-F; Chang, Eric C

    2015-07-21

    Basal-like breast cancers (BLBCs) are aggressive, and their drivers are unclear. We have found that wild-type N-RAS is overexpressed in BLBCs but not in other breast cancer subtypes. Repressing N-RAS inhibits transformation and tumor growth, whereas overexpression enhances these processes even in preinvasive BLBC cells. We identified N-Ras-responsive genes, most of which encode chemokines; e.g., IL8. Expression levels of these chemokines and N-RAS in tumors correlate with outcome. N-Ras, but not K-Ras, induces IL-8 by binding and activating the cytoplasmic pool of JAK2; IL-8 then acts on both the cancer cells and stromal fibroblasts. Thus, BLBC progression is promoted by increasing activities of wild-type N-Ras, which mediates autocrine/paracrine signaling that can influence both cancer and stroma cells.

  1. Fbxl10 overexpression in murine hematopoietic stem cells induces leukemia involving metabolic activation and upregulation of Nsg2

    DEFF Research Database (Denmark)

    Ueda, Takeshi; Nagamachi, Akiko; Takubo, Keiyo;

    2015-01-01

    investigate the role of Fbxl10 in leukemogenesis, we generated transgenic (Tg) mice that overexpress Fbxl10 in hematopoietic stem cells (HSCs). Interestingly, Fbxl10 Tg mice developed myeloid or B-lymphoid leukemia with complete penetrance. HSCs from the Tg mice exhibited an accelerated G0/G1 to S transition...

  2. Quantitative RT-PCR assays for the determination of urokinase-type plasminogen activator and plasminogen activator inhibitor type 1 mRNA in primary tumor tissue of breast cancer patients: comparison to antigen quantification by ELISA.

    NARCIS (Netherlands)

    Biermann, J.C.; Holzscheiter, L.; Kotzsch, M.; Luther, T.; Kiechle-Bahat, M.; Sweep, F.C.; Span, P.N.; Schmitt, M.; Magdolen, V.

    2008-01-01

    Urokinase-type plasminogen activator (uPA) and its inhibitor plasminogen activator inhibitor type 1 (PAI-1) play a key role in tumor-associated processes such as the degradation of extracellular matrix proteins, tissue remodeling, cell adhesion, migration, and invasion. High antigen levels of uPA an

  3. A20 overexpression inhibits lipopolysaccharide-induced NF-κB activation, TRAF6 and CD40 expression in rat peritoneal mesothelial cells.

    Science.gov (United States)

    Zou, Xun-Liang; Pei, De-An; Yan, Ju-Zhen; Xu, Gang; Wu, Ping

    2014-04-17

    Zinc finger protein A20 is a key negative regulator of inflammation. However, whether A20 may affect inflammation during peritoneal dialysis (PD)-associated peritonitis is still unclear. This study was aimed to investigate the effect of A20 overexpression on lipopolysaccharide (LPS)-induced inflammatory response in rat peritoneal mesothelial cells (RPMCs). Isolated and cultured RPMCs in vitro. Plasmid pGEM-T easy-A20 was transfected into RPMCs by Lipofectamine™2000. The protein expression of A20, phospho-IκBα, IκBα, TNF receptor-associated factor (TRAF) 6 and CD40 were analyzed by Western blot. The mRNA expression of TRAF6, CD40, interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) were determined by real time-PCR. NF-κB p65 DNA binding activity, IL-6 and TNF-α levels in cells culture supernatant were determined by ELISA. Our results revealed that RPMCs overexpression of A20 lead to significant decrease of LPS-induced IκBα phosphorylation and NF-κB DNA binding activity (all pTNF-α as well as levels of IL-6 and TNF-α in cells culture supernatant (all pinhibited CD40 expression. Our study indicated that A20 overexpression may depress the inflammatory response induced by LPS in cultured RPMCs through negatively regulated the relevant function of adaptors in LPS signaling pathway.

  4. Over-expression of miR-106b promotes cell migration and metastasis in hepatocellular carcinoma by activating epithelial-mesenchymal transition process.

    Directory of Open Access Journals (Sweden)

    Wing Lung Yau

    Full Text Available Hepatocellular carcinoma (HCC is one the the most fatal cancers worldwide. The poor prognosis of HCC is mainly due to the developement of distance metastasis. To investigate the mechanism of metastasis in HCC, an orthotopic HCC metastasis animal model was established. Two sets of primary liver tumor cell lines and corresponding lung metastasis cell lines were generated. In vitro functional analysis demonstrated that the metastatic cell line had higher invasion and migration ability when compared with the primary liver tumor cell line. These cell lines were subjected to microRNA (miRNAs microarray analysis to identify differentially expressed miRNAs which were associated with the developement of metastasis in vivo. Fifteen human miRNAs, including miR-106b, were differentially expressed in 2 metastatic cell lines compared with the primary tumor cell lines. The clinical significance of miR-106b in 99 HCC clinical samples was studied. The results demonstrated that miR-106b was over-expressed in HCC tumor tissue compared with adjacent non-tumor tissue (p = 0.0005, and overexpression of miR-106b was signficantly correlated with higher tumor grade (p = 0.018. Further functional studies demonstrated that miR-106b could promote cell migration and stress fiber formation by over-expressing RhoGTPases, RhoA and RhoC. In vivo functional studies also showed that over-expression of miR-106b promoted HCC metastasis. These effects were related to the activation of the epithelial-mesenchymal transition (EMT process. Our results suggested that miR-106b expression contributed to HCC metastasis by activating the EMT process promoting cell migration in vitro and metastasis in vivo.

  5. Targeting the autolysis loop of urokinase-type plasminogen activator with conformation-specific monoclonal antibodies

    DEFF Research Database (Denmark)

    Bøtkjær, Kenneth Alrø; Fogh, Sarah; Bekes, Erin C;

    2011-01-01

    , with high levels correlating with a poor prognosis. This observation has stimulated efforts into finding new principles for intervening with uPA's activity. In the present study we characterize the so-called autolysis loop in the catalytic domain of uPA as a potential inhibitory target. This loop was found...

  6. The expression and significance of u-PA and PAI-1 in human lupus nephritis%狼疮性肾炎中u-PA和PAI-1的表达及其意义

    Institute of Scientific and Technical Information of China (English)

    洪寅峰; 张志刚; 高山

    2001-01-01

    Objective To investigate the expression and significance of urokinase-type plasminogen activator (uPA) and type Ⅰ plasminogen activator inhibitor (PAI-1) in human lupus nephritis (LN). Method Immunohistochemistry and imaging analysis were used for detecting the intensity of expression of u-PA and PAI-1 in renal biopsied tissue of 50 cases with various types of LN and 10 cases with minor glomerular lesions (control group), the results were analyzed correlatively with PCNA cells and type IV collagen. Results The levels of u-PA and PAI-1 expression were different in various type of LN , in which, both were significantly higher than those of the minor glomerular lesion group (P<0.05), and the highest was LN-IV group. The staining intensity of PAI-1 expression was significantly stronger than that of u-PA in various type of LN (P <0.05), the increased expression of u-PA and PAI-1 were positively correlated with increased number of PCNA + cell (P <0.05), while the expression of PAI-1 was also closely related to increased deposition of type IV collagen in the glomeruli ( P <0.05). Conclusion The abnormal expression of u-PA and PAI-1 were associated with the extent of injury and types of LN and may be one of important factor in contributing to the progression and inimry in LN. (Shanghai Med J, 2001,24:169)%目的了解尿激酶型纤溶酶原激活物(u-PA)及其Ⅰ型抑制因子(PAI-1)在狼疮性肾炎(LN)肾小球病变中的表达及其意义。方法对50例不同类型的LN和10例原发性肾小球轻微病变的肾活检组织,采用免疫组化及图象分析法比较观察了u-PA和PAI-1在肾小球的表达强度,并与肾小球增殖细胞核抗原(PCNA)阳性细胞数和Ⅳ型胶原染色强度作相关分析。结果u-PA和PAI-1在各型LN病变肾小球中的表达,均比肾小球轻微病变明显增强(P<0.05或<0.01),并以LN-IV型为最明显。PAI-1的染色反应强于同组的u-PA,两者有显著差异(P<0.05)

  7. Overexpressed neuroglobin raises threshold for nitric oxide-induced impairment of mitochondrial respiratory activities and stress signaling in primary cortical neurons.

    Science.gov (United States)

    Singh, Shilpee; Zhuo, Ming; Gorgun, Falih M; Englander, Ella W

    2013-08-01

    Surges of nitric oxide compromise mitochondrial respiration primarily by competitive inhibition of oxygen binding to cytochrome c oxidase (complex IV) and are particularly injurious in neurons, which rely on oxidative phosphorylation for all their energy needs. Here, we show that transgenic overexpression of the neuronal globin protein, neuroglobin, helps diminish protein nitration, preserve mitochondrial function and sustain ATP content of primary cortical neurons challenged by extended nitric oxide exposure. Specifically, in transgenic neurons, elevated neuroglobin curtailed nitric oxide-induced alterations in mitochondrial oxygen consumption rates, including baseline oxygen consumption, consumption coupled with ATP synthesis, proton leak and spare respiratory capacity. Concomitantly, activation of genes involved in sensing and responding to oxidative/nitrosative stress, including the early-immediate c-Fos gene and the phase II antioxidant enzyme, heme oxygenase-1, was diminished in neuroglobin-overexpressing compared to wild-type neurons. Taken together, these differences reflect a lesser insult produced by similar concentrations of nitric oxide in neuroglobin-overexpressing compared to wild-type neurons, suggesting that abundant neuroglobin buffers nitric oxide and raises the threshold of nitric oxide-mediated injury in neurons.

  8. Inhibition of PMA-induced endothelial cell activation and adhesion by over-expression of domain negative IκBα protein

    Institute of Scientific and Technical Information of China (English)

    Jian-Feng Wei; Ke Sun; Shi-Guo Xu; Hai-Yang Xie; Shu-Sen Zheng

    2005-01-01

    AIM: NF-κB, regulate the expression of cytokine-inducible genes involving immune and inflammatory responses, will be potential therapy approach for allograft from rejection. In this study, we use pCMV-IκBαM vector to inhibit NF-κB activation and investigate the effect of pCMV-IκBαM in inhibition of T cells adhesion to endothelial cells. METHODS: The NF-κB activity was detected with pNF-κB reporter gene and electrophoretic mobility shift assay. Expression of cell surface molecules was detected by RT-PCR and flow cytometer. The cell-cell adhesion assay was performed to determine the effect of pCMV-IκBαM in inhibition of T cells adhesion to endothelial cells. RESULTS: We could find that NF-κB activity is inhibited by over-expression of non-degraded IκBα protein. Expression of adhesion molecules like ICAM-1, VCAM-1, and P-selectin as well as cell-cell adhesion were inhibited significantly by transfection of the pCMV-IκBαM vector. CONCLUSION: Our results indicate that the pCMVIκBαM, which inhibit the activity of NF-κB through over-expression of non-degraded IκBα protein, can be used for gene therapy in diseases involving NF-κB activation abnormally like organ transplantation via inhibiting cell adhesion.

  9. Life Testing of the Vapor Compression Distillation Urine Processing Assembly (VCD/UPA) at the Marshall Space Flight Center

    Science.gov (United States)

    Wieland, Paul O.

    1998-01-01

    Wastewater and urine generated on the International Space Station will be processed to recover pure water. The method selected is vapor compression distillation (VCD). To verify the long-term reliability and performance of the VCD Urine Processing Assembly (UPA), accelerated life testing was performed at the Marshall Space Flight Center (MSFC) from January 1993 to April 1996. Two UPAS, the VCD-5 and VCD-5A, were tested for 204 days and 665 days, respectively. The compressor gears and the distillation centrifuge drive belt were found to have an operating life of approximately 4800 hours. Precise alignment of the flex-spline of the fluids pump is essential to avoid failure of the pump after about 400 hours of operation. Also, leakage around the seals of the drive shaft of the fluids pump and purge pump must be eliminated for continued good performance. Results indicate that, with some design and procedural modifications and suitable quality control, the required performance and operational life can be met with the VCD/UPA.

  10. The Anti-Cancer Potency and Mechanism of a Novel Tumor-Activated Fused Toxin, DLM

    Directory of Open Access Journals (Sweden)

    Dejun Sun

    2015-02-01

    Full Text Available Melittin, which acts as a membrane-disrupting lytic peptide, is not only cytotoxic to tumors, but also vital to normal cells. Melittin had low toxicity when coupled with target peptides. Despite significant research development with the fused toxin, a new fused toxin is needed which has a cleavable linker such that the fused toxin can release melittin after protease cleavage on the tumor cell surface. We describe a novel fused toxin, composed of disintegrin, uPA (urokinase-type plasminogen activator-cleavable linker, and melittin. Disintegrin is a single strand peptide (73 aa isolated from Gloydius Ussuriensis venom. The RGD (Arg-Gly-Asp site of disintegrin dominates its interaction with integrins on the surface of the tumor cells. uPA is over-expressed and plays an important role in tumor cell invasiveness and metastatic progression. The DLM (disintegrin-linker-melittin linker is uPA-cleavable, enabling DLM to release melittin. We compared binding activity of our synthesized disintegrin with native disintegrin and report that DLM had less binding activity than the native form. uPA-cleavage was evaluated in vitro and the uPA-cleavable linker released melittin. Treating tumors expressing uPA with DLM enhanced tumor cell killing as well as reduced toxicity to erythrocytes and other non-cancerous normal cells. The mechanism behind DLM tumor cell killing was tested using a DNA ladder assay, fluorescent microscopy, flow cytometry, and transmission electron microscopy. Data revealed tumor cell necrosis as the mechanism of cell death, and the fused DLM toxin with an uPA-cleavable linker enhanced tumor selectivity and killing ability.

  11. A20 Overexpression Inhibits Lipopolysaccharide-Induced NF-κB Activation, TRAF6 and CD40 Expression in Rat Peritoneal Mesothelial Cells

    Directory of Open Access Journals (Sweden)

    Xun-Liang Zou

    2014-04-01

    Full Text Available Zinc finger protein A20 is a key negative regulator of inflammation. However, whether A20 may affect inflammation during peritoneal dialysis (PD-associated peritonitis is still unclear. This study was aimed to investigate the effect of A20 overexpression on lipopolysaccharide (LPS-induced inflammatory response in rat peritoneal mesothelial cells (RPMCs. Isolated and cultured RPMCs in vitro. Plasmid pGEM-T easy-A20 was transfected into RPMCs by Lipofectamine™2000. The protein expression of A20, phospho-IκBα, IκBα, TNF receptor-associated factor (TRAF 6 and CD40 were analyzed by Western blot. The mRNA expression of TRAF6, CD40, interleukin-6 (IL-6 and tumor necrosis factor-α (TNF-α were determined by real time-PCR. NF-κB p65 DNA binding activity, IL-6 and TNF-α levels in cells culture supernatant were determined by ELISA. Our results revealed that RPMCs overexpression of A20 lead to significant decrease of LPS-induced IκBα phosphorylation and NF-κB DNA binding activity (all p < 0.01. In addition, A20 also attenuated the expression of TRAF6, CD40, IL-6 and TNF-α as well as levels of IL-6 and TNF-α in cells culture supernatant (all p < 0.05. However, A20 only partly inhibited CD40 expression. Our study indicated that A20 overexpression may depress the inflammatory response induced by LPS in cultured RPMCs through negatively regulated the relevant function of adaptors in LPS signaling pathway.

  12. Diffuse glutamine synthetase overexpression restricted to areas of peliosis in a β-catenin-activated hepatocellular adenoma: a potential pitfall in glutamine synthetase interpretation.

    Science.gov (United States)

    Berry, Ryan S; Gullapalli, Rama R; Wu, Jin; Morris, Katherine; Hanson, Joshua A

    2014-08-01

    Hepatocellular adenomas have recently been classified into four subtypes based on molecular findings: hepatocyte nuclear factor 1α (HNF1α) inactivated, inflammatory/telangiectatic, β-catenin activated, and unclassifiable. β-catenin-activated adenomas have the potential for malignant transformation and are thus important to recognize. Diffuse glutamine synthetase immunohistochemical positivity has been shown to be a reliable surrogate marker for β-catenin activation, though variations in staining patterns may be difficult to interpret. We report a case of a peliotic adenoma that was morphologically consistent with a β-catenin wild-type hepatocellular adenoma but harbored a β-catenin mutation by molecular analysis. The tumor lacked nuclear β-catenin positivity and demonstrated a hitherto undescribed pattern of glutamine synthetase overexpression restricted to areas of peliosis with mostly negative staining in non-peliotic areas. This pattern was initially interpreted as physiologic and may represent a potential pitfall in glutamine synthetase interpretation.

  13. Matrine inhibits diethylnitrosamine-induced HCC proliferation in rats through inducing apoptosis via p53, Bax-dependent caspase-3 activation pathway and down-regulating MLCK overexpression.

    Science.gov (United States)

    Zhang, Xiaolin; Yu, Hao

    2016-01-01

    The proliferation of hepatocellular carcinoma (HCC) cells is one of the leading causes of liver cancer mortality in humans. The inhibiting effects of matrine on HCC cell proliferation have been studied, but the mechanism of that inhibition has not been fully elucidated. Since, apoptosis plays an important role in HCC cell proliferation. We examined the apoptosis-inducing effect of matrine on tumor cells. Western blot analysis of p53, Bax, cleaved caspase-3 and myosin light chain kinase (MLCK) revealed that matrine induced tumor cell apoptosis by controlling anoikis. It activated p53, Bax-dependent caspase-3 and blocked the ECM-integrin mediated cell survival pathway through down-regulating MLCK over-expression in the liver of rats with diethyl nitrosamine (DENA)-induced HCC. Our results suggest that matrine can inhibit the proliferation of HCC cells through inducing tumor cell apoptosis via activation of the p53 pathway and inhibition of MLCK overexpression. Matrine may thus be used as a potentially promising reagent to inhibit HCC cell proliferation and MLCK may be a novel target for the treatment of HCC.

  14. Combined effects of lapatinib and bortezomib in human epidermal receptor 2 (HER2)-overexpressing breast cancer cells and activity of bortezomib against lapatinib-resistant breast cancer cells.

    Science.gov (United States)

    Ma, Chuandong; Niu, Xiuqing; Luo, Jianmin; Shao, Zhimin; Shen, Kunwei

    2010-10-01

    Lapatinib and bortezomib are highly active against breast cancer cells. Breast cancer patients who initially respond to lapatinib may eventually manifest acquired resistance to this treatment. Thus, the identification of novel agents that may prevent or delay the development of acquired resistance to lapatinib is critical. In the current study, we show that the combination of lapatinib and bortezomib results in a synergistic growth inhibition in human epidermal receptor 2 (HER2)-overexpressing breast cancer cells and that the combination enhances apoptosis of SK-BR-3 cells. Importantly, we found that the combination of lapatinib plus bortezomib more effectively blocked activation of the HER2 pathway in SK-BR-3 cells, compared with monotherapy. In addition, we established a model of acquired resistance to lapatinib by chronically challenging SK-BR-3 breast cancer cells with increasing concentrations of lapatinib. Here, we showed that bortezomib notably induced apoptosis of lapatinib-resistant SK-BR-3 pools and further inhibited HER2 signaling in the resistant cells. Taken together, the current data indicate a synergistic interaction between lapatinib and bortezomib in HER2-overexpressing breast cancer cells and provide the rationale for the clinical evaluation of these two noncross-resistant targeted therapies. The combination of lapatinib and bortezomib may be a potentially novel approach to prevent or delay the onset of acquired resistance to lapatinib in HER2-overxpressing/estrogen receptor (ER)-negative breast cancers.

  15. Matrine inhibits diethylnitrosamine-induced HCC proliferation in rats through inducing apoptosis via p53, Bax-dependent caspase-3 activation pathway and down-regulating MLCK overexpression

    Science.gov (United States)

    Zhang, Xiaolin; Yu, Hao

    2016-01-01

    The proliferation of hepatocellular carcinoma (HCC) cells is one of the leading causes of liver cancer mortality in humans. The inhibiting effects of matrine on HCC cell proliferation have been studied, but the mechanism of that inhibition has not been fully elucidated. Since, apoptosis plays an important role in HCC cell proliferation. We examined the apoptosis-inducing effect of matrine on tumor cells. Western blot analysis of p53, Bax, cleaved caspase-3 and myosin light chain kinase (MLCK) revealed that matrine induced tumor cell apoptosis by controlling anoikis. It activated p53, Bax-dependent caspase-3 and blocked the ECM-integrin mediated cell survival pathway through down-regulating MLCK over-expression in the liver of rats with diethyl nitrosamine (DENA)-induced HCC. Our results suggest that matrine can inhibit the proliferation of HCC cells through inducing tumor cell apoptosis via activation of the p53 pathway and inhibition of MLCK overexpression. Matrine may thus be used as a potentially promising reagent to inhibit HCC cell proliferation and MLCK may be a novel target for the treatment of HCC. PMID:27642320

  16. MiR-1207 overexpression promotes cancer stem cell-like traits in ovarian cancer by activating the Wnt/β-catenin signaling pathway.

    Science.gov (United States)

    Wu, Geyan; Liu, Aibin; Zhu, Jinrong; Lei, Fangyong; Wu, Shu; Zhang, Xin; Ye, Liping; Cao, Lixue; He, Shanyang

    2015-10-06

    Wnt/β-catenin signaling pathway is strictly controlled by multiple negative regulators. However, how tumor cells override the negative regulatory effects to maintain constitutive activation of Wnt/β-catenin signaling, which is commonly observed in various cancers, remains puzzling. In current study, we reported that overexpression of miR-1207 in ovarian cancer activated Wnt/β-catenin signaling by directly targeting and suppressing secreted Frizzled-related protein 1 (SFRP1), AXIN2 and inhibitor of β-catenin and TCF-4 (ICAT), which are vital negative regulators of the Wnt/β-catenin pathway. We found that the expression of miR-1207 was ubiquitously upregulated in both ovarian cancer tissues and cells, which inversely correlated with patient overall survival. Furthermore, overexpression of miR-1207 enhanced, while silencing miR-1207 reduced, stem cell-like traits of ovarian cancer cells in vitro and in vivo, including tumor sphere formation capability and proportion of SP+ and CD133+ cells. Importantly, upregulating miR-1207 promoted, while silencing miR-1207 inhibited, the tumorigenicity of ovarian cancer cells. Hence, our results suggest that miR-1207 plays a vital role in promoting the cancer stem cell-like phenotype in ovarian cancer and might represent a potential target for anti-ovarian cancer therapy.

  17. The glucose-dependent insulinotropic polypeptide receptor is overexpressed amongst GNAS1 mutation-negative somatotropinomas and drives growth hormone (GH)-promoter activity in GH3 cells.

    Science.gov (United States)

    Occhi, G; Losa, M; Albiger, N; Trivellin, G; Regazzo, D; Scanarini, M; Monteserin-Garcia, J L; Fröhlich, B; Ferasin, S; Terreni, M R; Fassina, A; Vitiello, L; Stalla, G; Mantero, F; Scaroni, C

    2011-07-01

    Somatic mutations in the GNAS1 gene, encoding the α-subunit of the heterotrimeric stimulatory G protein (Gαs), occur in approximately 40% of growth hormone (GH)-secreting pituitary tumours. By altering the adenylate cyclase-cAMP-protein kinase A pathway, they unequivocally give somatotroph cells a growth advantage. Hence, the pathogenesis of somatotropinomas could be linked to anomalies in receptors coupled to the cAMP second-messenger cascade. Among them, the glucose-dependent insulinotropic polypeptide receptor (GIPR) is already known to play a primary role in the impaired cAMP-dependent cortisol secretion in patients affected by food-dependent Cushing's syndrome. In the present study, 43 somatotropinomas and 12 normal pituitary glands were investigated for GIPR expression by quantitative reverse transcriptase-polymerase chain reaction, western blotting and immunohistochemistry. Tumoural specimens were also evaluated for GNAS1 mutational status. The effect of GIPR overexpression on cAMP levels and GH transcription was evaluated in an in vitro model of somatotropinomas, the GH-secreting pituitary cell line GH3. GIPR was expressed at higher levels compared to normal pituitaries in 13 GNAS1 mutation-negative somatotropinomas. GIP stimulated adenylyl cyclase and GH-promoter activity in GIPR-transfected GH3 cells, confirming a correct coupling of GIPR to Gαs. In a proportion of acromegalic patients, GIPR overexpression appeared to be associated with a paradoxical increase in GH after an oral glucose tolerance test. Whether GIPR overexpression in acromegalic patients may be associated with this paradoxical response or more generally involved in the pathogenesis of acromegaly, as suggested by the mutually exclusive high GIPR levels and GNAS1 mutations, remains an open question.

  18. Resveratrol chemosensitizes HER-2-overexpressing breast cancer cells to docetaxel chemoresistance by inhibiting docetaxel-mediated activation of HER-2-Akt axis.

    Science.gov (United States)

    Vinod, B S; Nair, H H; Vijayakurup, V; Shabna, A; Shah, S; Krishna, A; Pillai, K S; Thankachan, S; Anto, R J

    2015-01-01

    As breast cancer cells often develop chemoresistance, better therapeutic options are in search to circumvent it. Here we demonstrate that human epidermal growth factor receptor-2 (HER-2)-overexpressing breast cancer cells resist docetaxel-induced cytotoxicity by upregulating HER-2 and its activity downstream, through Akt and mitogen-activated protein kinase (MAPK) pathways. We observed that introducing resveratrol as a chemosensitizer in docetaxel chemotherapy blocks upregulation and activation of HER-2 in addition to blocking downstream signaling pathways such as Akt. Resveratrol and docetaxel combination results in the synergistic induction of cell death in HER-2-overexpressing SK-BR-3 cells, whereas introduction of wild-type HER-2 in MDA-MD-231 cells increased the resistance to docetaxel. Dominant-negative HER-2 sensitizes SK-BR-3 cells to docetaxel. Our study identified a new synergistic therapeutic combination that targets HER-2-induced breast cancer resistance and might help to overcome therapeutic resistance during breast cancer therapy. The synergism of docetaxel and resveratrol was maximum in SK-BR-3, which is unique among the cell lines studied, due to its high expression status of HER-2, a receptor known to dictate the signaling environment of breast cancer cells. Docetaxel could further induce HER-2 activity in these cells, which was downregulated on resveratrol treatment. Transfection of DN-HER-2 in SK-BR-3 cells inhibits the synergism as the transfection itself sensitizes these cells to docetaxel, leaving no role for resveratrol, whereas ectopic expression of HER-2 introduces the synergism in MDA-MB-231, the triple-negative cell line, in which the synergism was minimum, attesting the crucial role of HER-2 in suppressing the sensitivity to docetaxel. Single-agent docetaxel induced HER-2-mediated resistance to cell death, which was blocked by resveratrol. Resveratrol also downregulated docetaxel-induced activation of MAPK and Akt, survival signaling

  19. Bcl-2 over-expression and activation of protein kinase C suppress the Trail-induced apoptosis in Jurkat T cells

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Trail,a tumor necrosis factor-related apoptosis-inducing ligand,is a novel potent endogenous activator of the cell death pathway through the activation of cell surface death receptors Trail-R1 and Trail-R2.Its role,like FasL in activation-induced cell death(AICD),has been demonstrated in immune system.However the mechanism of Trail induced apoptosis remains unclear.In this report,the recombinant Trail protein was expressed and purified.The apoptosis-inducing activity and the regulation mechanism of recombinant Trail on Jurkat T cells were explored in vitro.Trypan blue exclusion assay demonstrated that the recombinant Trail protein actively killed Jurkat T cells in a dose-dependent manner.Trail-induced apoptosis in Jurkat T cells were remarkably reduced by Bcl-2 over expression in Bcl-2 gene transfected cells.Treatment with PMA(phorbol 12-myristate 13-acetate),a PKC activator,suppressed Trail-induced apoptosis in Jurkat T cells.The inhibition of apoptosis by PMA was abolished by pretreatment with Bis,a PKC inhibitor.Taken together,it was suggested that Bcl-2 over-expression and PMA activated PKC actively down-regulated the Trail-mediated apoptosis in Jurkat T cell.

  20. Pyrrolidine dithiocarbamate (PDTC) inhibits the overexpression of MCP-1 and attenuates microglial activation in the hippocampus of a pilocarpine-induced status epilepticus rat model.

    Science.gov (United States)

    Lv, Rilang; Xu, Xiaoyun; Luo, Zheng; Shen, Nan; Wang, Feng; Zhao, Yongbo

    2014-01-01

    The aim of this study was to investigate the effects of pyrrolidine dithiocarbamate (PDTC) on MCP-1 expression and microglial activation in the hippocampus of a rat model of pilocarpine (PILO)-induced status epilepticus (SE). Moreover, seizure susceptibility, frequency and severity as well as brain damage were analyzed and changes in behavior were recorded. Chemokine MCP-1 expression and microglial activation were detected by immunohistochemistry (IHC). Fluoro-Jade C (FJC) and NeuN staining were used for the evaluation of tissue damage. Our results showed that although SE resulted in the upregulation of MCP-1 and microglial activation in the rat hippocampus 24 h after seizure onset, pretreatment with PDTC significantly inhibited the MCP-1 overexpression and attenuated the microglial activation. These effects were accompanied by neurodegenerative amelioration. To the best of our knowledge, these findings indicated for the first time that the activation of the nuclear factor-κB (NF-κB) pathway may contribute to MCP-1 upregulation and microglial activation in the context of epilepsy. PDTC was also shown to exert anticonvulsant activity and to have a neuroprotective effect on the hippocampal CA1 and CA3 regions, potentially through attenuating microglial activation.

  1. Overexpression of a GmCnx1 gene enhanced activity of nitrate reductase and aldehyde oxidase, and boosted mosaic virus resistance in soybean.

    Directory of Open Access Journals (Sweden)

    Zheng Zhou

    Full Text Available Molybdenum cofactor (Moco is required for the activities of Moco-dependant enzymes. Cofactor for nitrate reductase and xanthine dehydrogenase (Cnx1 is known to be involved in the biosynthesis of Moco in plants. In this work, a soybean (Glycine max L. Cnx1 gene (GmCnx1 was transferred into soybean using Agrobacterium tumefaciens-mediated transformation method. Twenty seven positive transgenic soybean plants were identified by coating leaves with phosphinothricin, bar protein quick dip stick and PCR analysis. Moreover, Southern blot analysis was carried out to confirm the insertion of GmCnx1 gene. Furthermore, expression of GmCnx1 gene in leaf and root of all transgenic lines increased 1.04-2.12 and 1.55-3.89 folds, respectively, as compared to wild type with GmCnx1 gene and in line 10 , 22 showing the highest expression. The activities of Moco-related enzymes viz nitrate reductase (NR and aldehydeoxidase (AO of T1 generation plants revealed that the best line among the GmCnx1 transgenic plants accumulated 4.25 μg g(-1 h(-1 and 30 pmol L(-1, respectively (approximately 2.6-fold and 3.9-fold higher than non-transgenic control plants.In addition, overexpression ofGmCnx1boosted the resistance to various strains of soybean mosaic virus (SMV. DAS-ELISA analysis further revealed that infection rate of GmCnx1 transgenic plants were generally lower than those of non-transgenic plants among two different virus strains tested. Taken together, this study showed that overexpression of a GmCnx1 gene enhanced NR and AO activities and SMV resistance, suggesting its important role in soybean genetic improvement.

  2. PII Overexpression in Lotus japonicus Affects Nodule Activity in Permissive Low-Nitrogen Conditions and Increases Nodule Numbers in High Nitrogen Treated Plants.

    Science.gov (United States)

    D'Apuzzo, Enrica; Valkov, Vladimir Totev; Parlati, Aurora; Omrane, Selim; Barbulova, Ani; Sainz, Maria Martha; Lentini, Marco; Esposito, Sergio; Rogato, Alessandra; Chiurazzi, Maurizio

    2015-04-01

    We report here the first characterization of a GLNB1 gene coding for the PII protein in leguminous plants. The main purpose of this work was the investigation of the possible roles played by this multifunctional protein in nodulation pathways. The Lotus japonicus LjGLB1 gene shows a significant transcriptional regulation during the light-dark cycle and different nitrogen availability, conditions that strongly affect nodule formation, development, and functioning. We also report analysis of the spatial profile of expression of LjGLB1 in root and nodule tissues and of the protein's subcellular localization. Transgenic L. japonicus lines overexpressing the PII protein were obtained and tested for the analysis of the symbiotic responses in different conditions. The uncoupling of PII from its native regulation affects nitrogenase activity and nodule polyamine content. Furthermore, our results suggest the involvement of PII in the signaling of the nitrogen nutritional status affecting the legumes' predisposition for nodule formation.

  3. Overexpression of the mitogen-activated protein kinase gene OsMAPK33 enhances sensitivity to salt stress in rice (Oryza sativa L.)

    Indian Academy of Sciences (India)

    Seong-Kon Lee; Beom-Gi Kim; Taek-Ryoun Kwon; Mi-Jeong Jeong; Sang-Ryeol Park; Jung-Won Lee; Myung-Ok Byun; Hawk-Bin Kwon; Benjamin F Matthews; Choo-Bong Hong; Soo-Chul Park

    2011-03-01

    Mitogen-activated protein kinases (MAPK) signalling cascades are activated by extracellular stimuli such as environmental stresses and pathogens in higher eukaryotic plants. To know more about MAPK signalling in plants, a MAPK cDNA clone, OsMAPK33, was isolated from rice. The gene is mainly induced by drought stress. In phylogenetic analysis, OsMAPK33 (Os02g0148100) showed approximately 47–93% identity at the amino acid level with other plant MAPKs. It was found to exhibit organ-specific expression with relatively higher expression in leaves as compared with roots or stems, and to exist as a single copy in the rice genome. To investigate the biological functions of OsMAPK33 in rice MAPK signalling, transgenic rice plants that either overexpressed or suppressed OsMAPK33 were made. Under dehydration conditions, the suppressed lines showed lower osmotic potential compared with that of wild-type plants, suggesting a role of OsMAPK33 in osmotic homeostasis. Nonetheless, the suppressed lines did not display any significant difference in drought tolerance compared with their wild-type plants. With increased salinity, there was still no difference in salt tolerance between OsMAPK33-suppressed lines and their wild-type plants. However, the overexpressing lines showed greater reduction in biomass accumulation and higher sodium uptake into cells, resulting in a lower K+/Na+ ratio inside the cell than that in the wild-type plants and OsMAPK33-suppressed lines. These results suggest that OsMAPK33 could play a negative role in salt tolerance through unfavourable ion homeostasis. Gene expression profiling of OsMAPK33 transgenic lines through rice DNA chip analysis showed that OsMAPK33 altered expression of genes involved in ion transport. Further characterization of downstream components will elucidate various biological functions of this novel rice MAPK.

  4. Glucose-stimulated insulin secretion does not require activation of pyruvate dehydrogenase: impact of adenovirus-mediated overexpression of PDH kinase and PDH phosphate phosphatase in pancreatic islets.

    Science.gov (United States)

    Nicholls, Linda I; Ainscow, Edward K; Rutter, Guy A

    2002-03-01

    Glucose-stimulated increases in mitochondrial metabolism are generally thought to be important for the activation of insulin secretion. Pyruvate dehydrogenase (PDH) is a key regulatory enzyme, believed to govern the rate of pyruvate entry into the citrate cycle. We show here that elevated glucose concentrations (16 or 30 vs 3 mM) cause an increase in PDH activity in both isolated rat islets, and in a clonal beta-cell line (MIN6). However, increases in PDH activity elicited with either dichloroacetate, or by adenoviral expression of the catalytic subunit of pyruvate dehydrogenase phosphatase, were without effect on glucose-induced increases in mitochondrial pyridine nucleotide levels, or cytosolic ATP concentration, in MIN6 cells, and insulin secretion from isolated rat islets. Similarly, the above parameters were unaffected by blockade of the glucose-induced increase in PDH activity by adenovirus-mediated over-expression of PDH kinase (PDK). Thus, activation of the PDH complex plays an unexpectedly minor role in stimulating glucose metabolism and in triggering insulin release.

  5. Involvement of urokinase-type plasminogen activator system in cancer: an overview.

    Science.gov (United States)

    Mekkawy, Ahmed H; Pourgholami, Mohammad H; Morris, David L

    2014-09-01

    Currently, there are several studies supporting the role of urokinase-type plasminogen activator (uPA) system in cancer. The association of uPA to its receptor triggers the conversion of plasminogen into plasmin. This process is regulated by the uPA inhibitors (PAI-1 and PAI-2). Plasmin promotes degradation of basement membrane and extracellular matrix (ECM) components as well as activation of ECM latent matrix metalloproteases. Degradation and remodeling of the surrounding tissues is crucial in the early steps of tumor progression by facilitating expansion of the tumor mass, release of tumor growth factors, activation of cytokines as well as induction of tumor cell proliferation, migration, and invasion. Hence, many tumors showed a correlation between uPA system component levels and tumor aggressiveness and survival. Therefore, this review summarizes the structure of the uPA system, its contribution to cancer progression, and the clinical relevance of uPA family members in cancer diagnosis. In addition, the review evaluates the significance of uPA system in the development of cancer-targeted therapies.

  6. Psc-AFP from Psoralea corylifolia L. overexpressed in Pichia pastoris increases antimicrobial activity and enhances disease resistance of transgenic tobacco.

    Science.gov (United States)

    Luo, Xiu-Mei; Xie, Cheng-Jian; Wang, De; Wei, Yun-Min; Cai, Jie; Cheng, Shan-Shan; Yang, Xing -Yong; Sui, An -Ping

    2017-02-01

    Psc-AFP, isolated from the seeds of Psoralea corylifolia L., is an antimicrobial protein with trypsin inhibitor activity. Its encoding gene was cloned by 3'- rapid amplification of cDNA ends (RACE) combined with Y-shaped adaptor-dependent extension (YADE) method. The gene Psc-AFP encodes a protein of 203 amino acids with a deduced signal peptide of 24 residues. The growth inhibition effect exerted by the heterologously expressed Psc-AFP in Pichia pastoris revealed that the recombinant Psc-AFP inhibited mycelium growth of Aspergillus niger, Rhizoctonia solani, and Alternaria brassicae and conidial germination of Alternaria alternata. The recombinant Psc-AFP also showed protease inhibitor activity manifested by the inhibition of trypsin. The transgenic tobacco bioassays confirmed that overexpressing Psc-AFP significantly enhanced the disease resistance of tobacco and that some of the transgenic lines were almost fully tolerant to Ralstonia solanacearum and A. alternata, whereas no apparent alteration in plant growth and development was observed. Collectively, these results indicate that the recombinant Psc-AFP is an active antimicrobial protein, with protease inhibitor activity that can be successfully produced in the yeast and tobacco and, therefore, maybe a potential antimicrobial candidate for practical use.

  7. Overexpression of erg20 gene encoding farnesyl pyrophosphate synthase has contrasting effects on activity of enzymes of the dolichyl and sterol branches of mevalonate pathway in Trichoderma reesei.

    Science.gov (United States)

    Piłsyk, Sebastian; Perlińska-Lenart, Urszula; Górka-Nieć, Wioletta; Graczyk, Sebastian; Antosiewicz, Beata; Zembek, Patrycja; Palamarczyk, Grażyna; Kruszewska, Joanna S

    2014-07-10

    The mevalonate pathway is the most diverse metabolic route resulting in the biosynthesis of at least 30,000 isoprenoid compounds, many of which, such as sterols or dolichols, are indispensable for living cells. In the filamentous fungus Trichoderma of major biotechnological interest isoprenoid metabolites are also involved in the biocontrol processes giving the mevalonate pathway an additional significance. On the other hand, little is known about genes coding for enzymes of the mevalonate pathway in Trichoderma. Here, we present cloning and functional analysis of the erg20 gene from Trichoderma reesei coding for farnesyl pyrophosphate (FPP) synthase (EC 2.5.1.10), an enzyme located at the branching point of the mevalonate pathway. Expression of the gene in a thermosensitive erg20-2 mutant of Saccharomyces cerevisiae impaired in the FPP synthase activity suppressed the thermosensitive phenotype. The same gene overexpressed in T. reesei significantly enhanced the FPP synthase activity and also stimulated the activity of cis-prenyltransferase, an enzyme of the dolichyl branch of the mevalonate pathway. Unexpectedly, the activity of squalene synthase from the other, sterol branch, was significantly decreased without, however, affecting ergosterol level.

  8. Nuclear reprogramming of luminal-like breast cancer cells generates Sox2-overexpressing cancer stem-like cellular states harboring transcriptional activation of the mTOR pathway

    Science.gov (United States)

    Corominas-Faja, Bruna; Cufí, Sílvia; Oliveras-Ferraros, Cristina; Cuyàs, Elisabet; López-Bonet, Eugeni; Lupu, Ruth; Alarcón, Tomás; Vellon, Luciano; Iglesias, Juan Manuel; Leis, Olatz; Martín, Ángel G; Vazquez-Martin, Alejandro; Menendez, Javier A

    2013-01-01

    Energy metabolism plasticity enables stemness programs during the reprogramming of somatic cells to an induced pluripotent stem cell (iPSC) state. This relationship may introduce a new era in the understanding of Warburg’s theory on the metabolic origin of cancer at the level of cancer stem cells (CSCs). Here, we used Yamanaka’s stem cell technology in an attempt to create stable CSC research lines in which to dissect the transcriptional control of mTOR—the master switch of cellular catabolism and anabolism—in CSC-like states. The rare colonies with iPSC-like morphology, obtained following the viral transduction of the Oct4, Sox2, Klf4, and c-Myc (OSKM) stemness factors into MCF-7 luminal-like breast cancer cells (MCF-7/Rep), demonstrated an intermediate state between cancer cells and bona fide iPSCs. MCF-7/Rep cells notably overexpressed SOX2 and stage-specific embryonic antigen (SSEA)-4 proteins; however, other stemness-related markers (OCT4, NANOG, SSEA-1, TRA-1–60, and TRA-1–81) were found at low to moderate levels. The transcriptional analyses of OSKM factors confirmed the strong but unique reactivation of the endogenous Sox2 stemness gene accompanied by the silencing of the exogenous Sox2 transgene in MCF-7/Rep cells. Some but not all MCF-7/Rep cells acquired strong alkaline phosphatase (AP) activity compared with MCF-7 parental cells. SOX2-overexpressing MCF-7/Rep cells contained drastically higher percentages of CD44+ and ALDEFLUOR-stained ALDHbright cells than MCF-7 parental cells. The overlap between differentially expressed mTOR signaling-related genes in 3 different SOX2-overexpressing CSC-like cell lines revealed a notable downregulation of 3 genes, PRKAA1 (which codes for the catalytic α 1 subunit of AMPK), DDIT4/REDD1 (a stress response gene that operates as a negative regulator of mTOR), and DEPTOR (a naturally occurring endogenous inhibitor of mTOR activity). The insulin-receptor gene (INSR) was differentially upregulated in MCF-7/Rep

  9. Inhibition of migration and invasion of carcinoma cells by urokinase-derived antagonists of alphavbeta5 integrin activation.

    Science.gov (United States)

    Vocca, Immacolata; Franco, Paola; Alfano, Daniela; Votta, Giuseppina; Carriero, Maria Vincenza; Estrada, Yeriel; Caputi, Mario; Netti, Paolo A; Ossowski, Liliana; Stoppelli, Maria Patrizia

    2009-01-15

    We previously showed that, while binding to urokinase receptor (uPAR) through its growth factor domain (GFD, residues 1-49), urokinase (uPA) can engage alphavbeta5 integrin through an internal domain (CP, residues 132-158). This novel uPA/alphavbeta5 interaction promotes cytoskeletal rearrangements and directional cell migration (Franco et al., J Cell Sci 2006;119:3424-34). We now show that treatment of cells with phosphomimic uPA (uPA138E/303E, serine 138 and 303 substituted with glutamic acid) strongly inhibits matrix-induced cell migration. Unlike uPA, binding of uPA138E/303E to cell surface did not induce F-actin enriched protruding structures and caused a 5-fold reduction in cell translocation speed, as determined by video tracking of living cells. Inhibition of migration was found to be independent of uPAR, since uPA variants lacking the GFD domain, but carrying the relevant Ser to Glu substitutions were as effective inhibitor as uPA138E/303E. Through several independent approaches, we established that the phosphomimics specifically bind to alphavbeta5 integrin through the CP region carrying the S138E mutation. This interaction blocks integrin activation, as determined by a decreased affinity of alphavbeta5 to vitronectin and a reduced association of the beta5 cytoplasmic tail with talin. Finally, stable expression of uPA138E/303E in human squamous carcinoma cells prevented tumor cell invasion in vivo. Thus, when expressed in cancer cells, the inhibitory phosphomimic effect was dominant over the effect of endogenously produced uPA. These results shed light on the regulation of cell migration by uPA phosphorylation and provide a realistic opportunity for a novel antiinvasive/metastatic therapeutic intervention.

  10. Overexpression of Fc receptor-like 1 associated with B-cell activation during hepatitis B virus infection

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Ke [Key Laboratory of Nuclear Medicine, Ministry of Health, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi, Jiangsu Province (China); Pei, Hao [Wuxi Hospital of Infectious Disease, Wuxi, Jiangsu Province (China); Huang, Biao; Yang, Run-Lin [Key Laboratory of Nuclear Medicine, Ministry of Health, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi, Jiangsu Province (China); Wu, Hang-Yuan [Wuxi Hospital of Infectious Disease, Wuxi, Jiangsu Province (China); Zhu, Xue; Zhu, Lan [Key Laboratory of Nuclear Medicine, Ministry of Health, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi, Jiangsu Province (China)

    2012-08-17

    The role of B cells in the pathogenesis of hepatitis B virus (HBV) infection has not been explored in depth. In the present study, the activation status of B cells from peripheral blood of healthy controls (N = 20) and patients with acute hepatitis B (AHB, N = 15) or chronic hepatitis B (CHB, N = 30) was evaluated by measuring the expression levels of B-cell activation markers CD69 and CD86, using quantitative real-time PCR and flow cytometry. Moreover, the potential mechanism underlying B-cell activation during HBV infection was further investigated by analyzing the expression profile of FCRL1, an intrinsic activation molecule of B cells. An elevation in the levels of B-cell activation markers including CD69 and CD86 was observed in the AHB patients (44.31 ± 9.27, 27.64 ± 9.26%) compared to CHB patients (30.35 ± 11.27, 18.41 ± 6.56%, P < 0.05), which was still higher than healthy controls (12.23 ± 7.84, 8.22 ± 3.43%, P < 0.05). Furthermore, the expression of FCRL1 was found to be similar to B-cell activation markers, which was highest in AHB patients (70.15 ± 17.11%), lowest in healthy donors (36.32 ± 9.98%, P < 0.05) and half-way between these levels in patients with CHB (55.17 ± 12.03%, P < 0.05). The results were positively associated with aberrant B-cell activation. These data suggest that B cells can play a role in HBV infection, and therefore more effort should be devoted to exploring their functions.

  11. Overexpression of AtFRO6 in transgenic tobacco enhances ferric chelate reductase activity in leaves and increases tolerance to iron-deficiency chlorosis.

    Science.gov (United States)

    Li, Li-Ya; Cai, Qiu-Yi; Yu, Dian-Si; Guo, Chang-Hong

    2011-08-01

    The Arabidopsis gene FRO6(AtFRO6) encodes ferric chelate reductase and highly expressed in green tissues of plants. We have expressed the gene AtFRO6 under the control of a 35S promoter in transgenic tobacco plants. High-level expression of AtFRO6 in transgenic plants was confirmed by northern blot analysis. Ferric reductase activity in leaves of transgenic plants grown under iron-sufficient or iron-deficient conditions is 2.13 and 1.26 fold higher than in control plants respectively. The enhanced ferric reductase activity led to increased concentrations of ferrous iron and chlorophyll, and reduced the iron deficiency chlorosis in the transgenic plants, compared to the control plants. In roots, the concentration of ferrous iron and ferric reductase activity were not significantly different in the transgenic plants compared to the control plants. These results suggest that FRO6 functions as a ferric chelate reductase for iron uptake by leaf cells, and overexpression of AtFRO6 in transgenic plants can reduce iron deficiency chlorosis.

  12. Overexpression of guanylate cyclase activating protein 2 in rod photoreceptors in vivo leads to morphological changes at the synaptic ribbon

    OpenAIRE

    Natalia López-del Hoyo; Lucrezia Fazioli; Santiago López-Begines; Laura Fernández-Sánchez; Nicolás Cuenca; Jordi Llorens; Pedro de la Villa; Ana Méndez

    2012-01-01

    Guanylate cyclase activating proteins are EF-hand containing proteins that confer calcium sensitivity to retinal guanylate cyclase at the outer segment discs of photoreceptor cells. By making the rate of cGMP synthesis dependent on the free intracellular calcium levels set by illumination, GCAPs play a fundamental role in the recovery of the light response and light adaptation. The main isoforms GCAP1 and GCAP2 also localize to the synaptic terminal, where their function is not known. Based o...

  13. A integração das Unidades de Pronto Atendimento (UPA com a rede assistencial no município do Rio de Janeiro, Brasil

    Directory of Open Access Journals (Sweden)

    Mariana Teixeira Konder

    2016-01-01

    Full Text Available No município do Rio de Janeiro, a implantação das Unidades de Pronto Atendimento 24h (UPA foi o fio condutor da política de saúde e modelo para estruturação da rede de urgência e emergência (RUE. Este estudo analisou a integração das UPAs na rede assistencial do município. Foram realizadas nove entrevistas, com gestores centrais e locais, analisadas à luz da Teoria da Estruturação de Giddens. Resultados mostraram pouca integração das UPAs, por deficiências estruturais da rede de serviços e fragmentação gerencial, pela ausência de governança unificada. Apesar do investimento político e financeiro, essa estratégia não logrou contornar os problemas de integração entre as unidades de saúde e, ainda, ressaltou a baixa prioridade governamental para a atenção básica. Assim, as UPAs pouco contribuíram para o desenvolvimento de redes de atenção à saúde e para a reorientação do modelo assistencial.

  14. Decreased 11β-Hydroxysteroid Dehydrogenase 1 Level and Activity in Murine Pancreatic Islets Caused by Insulin-Like Growth Factor I Overexpression.

    Directory of Open Access Journals (Sweden)

    Subrata Chowdhury

    Full Text Available We have reported a high expression of IGF-I in pancreatic islet β-cells of transgenic mice under the metallothionein promoter. cDNA microarray analysis of the islets revealed that the expression of 82 genes was significantly altered compared to wild-type mice. Of these, 11β-hydroxysteroid dehydrogenase 1 (11β-HSD1, which is responsible for the conversion of inert cortisone (11-dehydrocorticosterone, DHC in rodents to active cortisol (corticosterone in the liver and adipose tissues, has not been identified previously as an IGF-I target in pancreatic islets. We characterized the changes in its protein level, enzyme activity and glucose-stimulated insulin secretion. In freshly isolated islets, the level of 11β-HSD1 protein was significantly lower in MT-IGF mice. Using dual-labeled immunofluorescence, 11β-HSD1 was observed exclusively in glucagon-producing, islet α-cells but at a lower level in transgenic vs. wild-type animals. MT-IGF islets also exhibited reduced enzymatic activities. Dexamethasone (DEX and DHC inhibited glucose-stimulated insulin secretion from freshly isolated islets of wild-type mice. In the islets of MT-IGF mice, 48-h pre-incubation of DEX caused a significant decrease in insulin release, while the effect of DHC was largely blunted consistent with diminished 11β-HSD1 activity. In order to establish the function of intracrine glucocorticoids, we overexpressed 11β-HSD1 cDNA in MIN6 insulinoma cells, which together with DHC caused apoptosis and a significant decrease in proliferation. Both effects were abolished with the treatment of an 11β-HSD1 inhibitor. Our results demonstrate an inhibitory effect of IGF-I on 11β-HSD1 expression and activity within the pancreatic islets, which may mediate part of the IGF-I effects on cell proliferation, survival and insulin secretion.

  15. The amino-terminal domain of human signal transducers and activators of transcription 1: Overexpression, purification and characterization

    Indian Academy of Sciences (India)

    Arati Prabhu; Evans Coutinho; Sudha Srivastava

    2005-12-01

    The dual functional signal transducers and activators of transcription (STAT) proteins are latent cytoplasmic transcription factors that play crucial roles in host defense. Animals that lack these proteins are highly susceptible to microbial and viral infections and chemically induced primary tumours. We have over expressed the aminoterminal domain of human STAT1 (hSTAT1) in Escherichia coli and purified it by affinity chromatography and gel filtration chromatography. The entire process has been monitored by gel electrophoresis. The pure protein has been characterized by mass spectrometry and 2-dimensional nuclear magnetic resonance (2D-NMR) spectroscopy. Our results indicate that the N-terminus of hSTAT1 exists as a dimer in solution.

  16. Generation of a transformant showing higher manganese peroxidase (Mnp) activity by overexpression of Mnp gene in Trametes versicolor.

    Science.gov (United States)

    Yeo, Sumin; Park, Nammee; Song, Hong-Gyu; Choi, Hyoung T

    2007-06-01

    Trametes versicolor has a lignin degrading enzyme system, which is also involved in the degradation of diverse recalcitrant compounds. Manganese-dependent peroxidase (MnP) is one of the lignin degrading enzymes in T. versicolor. In this study, a cDNA clone of a putative MnP-coding gene was cloned and transferred into an expression vector (pBARGPE1) carrying a phosphinothricin resistance gene (bar) as a selectable marker to yield the expression vector, pBARTvMnP2. Transformants were generated through genetic transformation using pBARTvMnP2. The genomic integration of the MnP clone was confirmed by PCR with bar-specific primers. One transformant showed higher enzyme activity than the recipient strain did, and was genetically stable even after 10 consecutive transfers on non-selective medium.

  17. Potential clinical relevance of uPA and PAI-1 levels in node-negative, postmenopausal breast cancer patients bearing histological grade II tumors with ER/PR expression, during an early follow-up.

    Science.gov (United States)

    Buta, Marko; Džodić, Radan; Đurišić, Igor; Marković, Ivan; Vujasinović, Tijana; Markićević, Milan; Nikolić-Vukosavljević, Dragica

    2015-09-01

    We evaluated urokinase-type plasminogen activator (uPA) and plasminogen activator inhibitor-1 (PAI-1) prognostic value in postmenopausal, node-negative breast cancer patients bearing tumors with estrogen receptor (ER)/progesterone receptor (PR) expression, treated with locoregional therapy alone, within an early follow-up. We focused our analysis on tumors of histological grade II in order to improve its prognostic value and, consequently, to improve a decision-making process. The cytosol extracts of 73 tumor samples were used for assessing several biomarkers. ER and PR levels were measured by classical biochemical method. Cathepsin D was assayed by a radiometric immunoassay while both uPA and PAI-1 level determinations were performed by enzyme-linked immunosorbent assays. HER-2 gene amplification was determined by chromogenic in situ hybridization (CISH) in primary tumor tissue. Patients bearing tumors smaller than or equal to 2 cm (pT1) or those with low PAI-1 levels (PAI-1 PAI-1 levels, respectively. Analyses of 4 phenotypes, defined by tumor size and PAI-1 status, revealed that patients bearing either pT1 tumors, irrespective of PAI-1 levels, or pT2,3 tumors with low PAI-1 levels, had similar disease-free interval probabilities and showed favorable outcome compared to those bearing pT2,3 tumors with high PAI-1 levels. Our findings suggest that tumor size and PAI-1, used in combination as phenotypes are not only prognostic but might also be predictive in node-negative, postmenopausal breast cancer patients bearing histological grade II tumors with ER/PR expression, during an early follow-up period.

  18. Abnormal B-cell activation associated with TALL-1 over-expression and SOCS-1 suppression during chronic hepatitis C virus infection.

    Science.gov (United States)

    Moorman, Jonathan; Dong, Zhi P; Ni, Lei; Zhang, Chunlan; Borthwick, Thomas; Yao, Zhi Q

    2009-10-01

    Chronic hepatitis C virus (HCV) infection is associated with cirrhosis, autoimmunity and lymphoproliferative disorders. We have previously reported a differential regulation of T and B lymphocytes by HCV core protein in vitro. In this report, we employed a translational approach to characterize the activation status of peripheral B cells from individuals with chronic HCV infection and to explore potential mechanisms for B-cell dysregulation in the setting of HCV infection. In contrast to the T-cell suppression observed in HCV-infected individuals, B cells exhibit a non-specific polyclonal activation phenotype, characterized by significantly higher levels of (1) the early activation marker, CD69, (2) the costimulatory molecule, CD86, and (3) the CCR5 chemokine receptor, CD195, when compared with B cells from healthy donors in response to phytohaemagglutinin (PHA) stimulation. Importantly, tumour necrosis factor- and Apo-L-related leucocyte-expressed ligand-1 (TALL-1), also known as B-lymphocyte stimulator (BLYS), was found to be up-regulated on the surface of B cells from HCV patients in response to PHA as well as HCV core antigen stimulation. This up-regulation of TALL-1 was associated with vigorous memory B-cell responses to viral antigenic stimulation. Additionally, suppressor of cytokine signalling-1 (SOCS-1), a negative feedback immunoregulator that is inhibited in B lymphocytes by HCV core in vitro, was also inhibited in B cells from HCV patients when compared with healthy donors. These findings suggest that TALL-1 over-expression and SOCS-1 suppression are associated with aberrant B-cell activation, providing a plausible basis for the B-cell clonal expansion underlying the lymphoproliferative disorders and autoimmune phenomena observed during chronic HCV infection.

  19. Cell homeostasis in a Leishmania major mutant overexpressing the spliced leader RNA is maintained by an increased proteolytic activity.

    Science.gov (United States)

    Toledo, Juliano S; Ferreira, Tiago R; Defina, Tânia P A; Dossin, Fernando de M; Beattie, Kenneth A; Lamont, Douglas J; Cloutier, Serge; Papadopoulou, Barbara; Schenkman, Sergio; Cruz, Angela K

    2010-10-01

    Although several stage-specific genes have been identified in Leishmania, the molecular mechanisms governing developmental gene regulation in this organism are still not well understood. We have previously reported an attenuation of virulence in Leishmania major and L. braziliensis carrying extra-copies of the spliced leader RNA gene. Here, we surveyed the major differences in proteome and transcript expression profiles between the spliced leader RNA overexpressor and control lines using two-dimensional gel electrophoresis and differential display reverse transcription PCR, respectively. Thirty-nine genes related to stress response, cytoskeleton, proteolysis, cell cycle control and proliferation, energy generation, gene transcription, RNA processing and post-transcriptional regulation have abnormal patterns of expression in the spliced leader RNA overexpressor line. The evaluation of proteolytic pathways in the mutant revealed a selective increase of cysteine protease activity and an exacerbated ubiquitin-labeled protein population. Polysome profile analysis and measurement of cellular protein aggregates showed that protein translation in the spliced leader RNA overexpressor line is increased when compared to the control line. We found that L. major promastigotes maintain homeostasis in culture when challenged with a metabolic imbalance generated by spliced leader RNA surplus through modulation of intracellular proteolysis. However, this might interfere with a fine-tuned gene expression control necessary for the amastigote multiplication in the mammalian host.

  20. Enhanced levels of urokinase plasminogen activator and its soluble receptor in common variable immunodeficiency

    DEFF Research Database (Denmark)

    Fevang, Børre; Eugen-Olsen, Jesper; Yndestad, Arne;

    2009-01-01

    Common variable immunodeficiency (CVID) is a heterogeneous syndrome characterized by defective immunoglobulin production and high frequency of bacterial infections, autoimmunity and manifestations of chronic inflammation. The urokinase plasminogen activator (uPA), its cell bound and soluble recep...

  1. Role of Urokinase-type Plasminogen Activator in the Precontact Sperm-egg Communication and Fertility of Mice in vitro

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Objective To explore the role of urokinase-type plasminogen activator(uPA) in precontact sperm-egg communication and fertility of mice in vitro.Methods Firstly, sperm chemotaxis (SC) induced by uPA was assayed by measuring the sperm densities in capillaries with a descending gradient or no gradient of uPA respectively. Secondly, the role of uPAR that exists in sperm plasma membrane in SC was studied by examining the change of sperm density in capillary after incubating spermatozoa with anti-uPAR antibody. Thirdly, SC induced by eggs, which had been treated with uPA, PAI-1 and anti-uPAR beforehand respectively, was assayed to study the role of uPA in PSEC. Lastly, the fertilization capability of spermatozoa treated with uPA was examined by counting the number of fertilized eggs.Results 1)The density of spermatozoa that migrated down the gradient of uPA into the capillary was significantly lower than that into the capillary containing no-gradient uPA. 2) When uPAR of spermatozoa was inhibited by anti-uPAR antibody, the density of spermatozoa that migrated into the capillary with ascending gradient of uPA decreased correspondingly. 3) The density of spermatozoa attracted by eggs, which were treated with uPA beforehand, increased significantly than that of attracted by non-treated eggs. On the contrary, the sperm density decreased correspondingly when the egg was treated with PAI-1. 4) The number of fertilized eggs increased significantly after the spermatozoa used here was treated with uPA beforehand.Conclusion uPA could induce SC of mice sperm in vitro through the uPAR on its membrane, enhance the capability of egg inducing SC, and promote spermatozoa to fertilize eggs. Thus, uPA may act as an attractant in PSEC, increase the chance encounter of spermatozoa and eggs, therefore, enhance the fertility success correspondingly.This study, in some degree, provides an evidence that uPA may be used as a new medicine and diagnostic reagent for male infertility.

  2. Overexpression of the Large-Conductance, Ca2+-Activated K+ (BK) Channel Shortens Action Potential Duration in HL-1 Cardiomyocytes.

    Science.gov (United States)

    Stimers, Joseph R; Song, Li; Rusch, Nancy J; Rhee, Sung W

    2015-01-01

    Long QT syndrome is characterized by a prolongation of the interval between the Q wave and the T wave on the electrocardiogram. This abnormality reflects a prolongation of the ventricular action potential caused by a number of genetic mutations or a variety of drugs. Since effective treatments are unavailable, we explored the possibility of using cardiac expression of the large-conductance, Ca2+-activated K+ (BK) channel to shorten action potential duration (APD). We hypothesized that expression of the pore-forming α subunit of human BK channels (hBKα) in HL-1 cells would shorten action potential duration in this mouse atrial cell line. Expression of hBKα had minimal effects on expression levels of other ion channels with the exception of a small but significant reduction in Kv11.1. Patch-clamped hBKα expressing HL-1 cells exhibited an outward voltage- and Ca2+-sensitive K+ current, which was inhibited by the BK channel blocker iberiotoxin (100 nM). This BK current phenotype was not detected in untransfected HL-1 cells or in HL-1 null cells sham-transfected with an empty vector. Importantly, APD in hBKα-expressing HL-1 cells averaged 14.3 ± 2.8 ms (n = 10), which represented a 53% reduction in APD compared to HL-1 null cells lacking BKα expression. APD in the latter cells averaged 31.0 ± 5.1 ms (n = 13). The shortened APD in hBKα-expressing cells was restored to normal duration by 100 nM iberiotoxin, suggesting that a repolarizing K+ current attributed to BK channels accounted for action potential shortening. These findings provide initial proof-of-concept that the introduction of hBKα channels into a cardiac cell line can shorten APD, and raise the possibility that gene-based interventions to increase hBKα channels in cardiac cells may hold promise as a therapeutic strategy for long QT syndrome.

  3. Overexpression of Elafin in Ovarian Carcinoma Is Driven by Genomic Gains and Activation of the Nuclear Factor κB Pathway and Is Associated with Poor Overall Survival

    Directory of Open Access Journals (Sweden)

    Adam Clauss

    2010-02-01

    Full Text Available Ovarian cancer is a leading cause of cancer mortality in women. The aim of this study was to elucidate whether whey acidic protein (WAP genes on chromosome 20q13.12, a region frequently amplified in this cancer, are expressed in serous carcinoma, the most common form of the disease. Herein, we report that a trio of WAP genes (HE4, SLPI, and Elafin is overexpressed and secreted by serous ovarian carcinomas. To our knowledge, this is the first report linking Elafin to ovarian cancer. Fluorescence in situ hybridization analysis of primary tumors demonstrates genomic gains of the Elafin locus in a majority of cases. In addition, a combination of peptidomimetics, RNA interference, and chromatin immunoprecipitation experiments shows that Elafin expression can be transcriptionally upregulated by inflammatory cytokines through activation of the nuclear factor κB pathway. Importantly, using a clinically annotated tissue microarray composed of late-stage, high-grade serous ovarian carcinomas, we show that Elafin expression correlates with poor overall survival. These results, combined with our observation that Elafin is secreted by ovarian tumors and is minimally expressed in normal tissues, suggest that Elafin may serve as a determinant of poor survival in this disease.

  4. Overexpression of Rhizomucor miehei Lipase and Activity Assay%米黑霉脂肪酶基因的高效表达及活性测定

    Institute of Scientific and Technical Information of China (English)

    王珏; 王丹; 张兵; 于洪巍

    2012-01-01

    为了实现米黑霉脂肪酶(Rhizomucor miehei Lipase,RML)基因在大肠杆菌中的高效表达,并得到大量的具有生物活性的脂肪酶,首先通过3种方式提高RML在大肠杆菌中可溶性蛋白的表达量:1)低温诱导(16℃)RML表达;2)新型分子伴侣(Skp)与RML N端融合表达;3)载体pET32a上的Trx·tag与RML N端融合表达.其次对各蛋白质进行纯化及活性测定,各种条件得到的RML比活在(226±10~247±10) U/mg.蛋白质表达结果显示:经低温诱导RML的效果最好,纯蛋白质量浓度为0.86 mg/mL,表明诱导温度是影响可溶性蛋白质表达量的关键因素;活性测定结果表明,Skp和Trx· tag与目的基因N端的融合没有影响RML活性中心(C末端)对底物的结合和催化能力.因此,RML不仅在大肠杆菌中得到高效表达,并且保持原有生物学活性,在工业生产中有应用价值.%In order to overexpress the Rhizomucor miehei Lipase (RML) gene and obtain a large number of bioactive proteins in Escherichia coli. Firstly,the research improved the amount of the soluble protein through three methods: 1) RML was introduced at 16 CC. 2) RML was fused with a new chaperone (Skp) which was located at the N terminal of RML;3) RML was fused with the Trx. tag in pET32a and the tag was located at the N terminal of RML Secondly,the specific activity of purified RML derived from different methods was detected as (226±10-247+10) U/mg. The expression result showed that the low-temperature inducing was best method and the concentration of RML was 0.86 mg/mL It was proposed that the temperature was the key factor of controling the amount of soluble protein. The activity test showed that fusion of Skr/Trx·tag and the N terminal of RML did not change the activity center (C terminal) and the catalytic ability of RML Therefore,the strategy for overexpression of RML in E.coli kept the biologycal activity and was valuble in the practice.

  5. Apigenin induces caspase-dependent apoptosis by inhibiting signal transducer and activator of transcription 3 signaling in HER2-overexpressing SKBR3 breast cancer cells.

    Science.gov (United States)

    Seo, Hye-Sook; Ku, Jin Mo; Choi, Han-Seok; Woo, Jong-Kyu; Jang, Bo-Hyoung; Go, Hoyeon; Shin, Yong Cheol; Ko, Seong-Gyu

    2015-08-01

    Phytoestrogens have been demonstrated to inhibit tumor induction; however, their molecular mechanisms of action have remained elusive. The present study aimed to investigate the effects of a phytoestrogen, apigenin, on proliferation and apoptosis of the human epidermal growth factor receptor 2 (HER2)-expressing breast cancer cell line SKBR3. Proliferation assay, MTT assay, fluorescence-activated cell sorting analysis, western blot analysis, immunocytochemistry, reverse transcription-polymerase chain reaction and ELISA assay were used in the present study. The results of the present study indicated that apigenin inhibited the proliferation of SKBR3 cells in a dose-and time-dependent manner. This inhibition of growth was accompanied by an increase in the sub-G0/G1 apoptotic population. Furthermore, apigenin enhanced the expression levels of cleaved caspase-8 and -3, and induced the cleavage of poly(adenosine diphosphate ribose) polymerase in SKBR3 cells, confirming that apigenin promotes apoptosis via a caspase-dependent pathway. Apigenin additionally reduced the expression of phosphorylated (p)-janus kinase 2 and p-signal transducer and activator of transcription 3 (STAT3), inhibited CoCl2-induced vascular endothelial growth factor (VEGF) secretion and decreased the nuclear localization of STAT3. The STAT3 inhibitor S31-201 decreased the cellular proliferation rate and reduced the expression of p-STAT3 and VEGF. Therefore, these results suggested that apigenin induced apoptosis via the inhibition of STAT3 signaling in SKBR3 cells. In conclusion, the results of the present study indicated that apigenin may be a potentially useful compound for the prevention or treatment of HER2-overexpressing breast cancer.

  6. EMMPRIN/CD147 up-regulates urokinase-type plasminogen activator: implications in oral tumor progression

    Directory of Open Access Journals (Sweden)

    Lescaille Géraldine

    2012-03-01

    Full Text Available Abstract Backgrounds An elevated level of EMMPRIN in cancer tissues have been correlated with tumor invasion in numerous cancers including oral cavity and larynx. Although EMMPRIN's effect has been generally attributed to its MMP inducing activity, we have previously demonstrated in breast cancer model that EMMPRIN can also enhance invasion by upregulating uPA. In this study, the role of EMMPRIN in regulating uPA and invasion was investigated in oral squamous cell carcinoma (OSCC progression. Methods Precancerous and invasive oral tumoral tissues were used as well as the corresponding cell lines, DOK and SCC-9 respectively. The paracrine regulation of uPA by EMMPRIN was investigated by treating culture cells with EMMPRIN-enriched membrane vesicles. UPA expression was analyzed by qPCR and immunostaining and the consequence on the invasion capacity was studied using modified Boyden chamber assay, in the presence or absence of EMMPRIN blocking antibody, the uPA inhibitor amiloride or the MMP inhibitor marimastat. Results OSCC tumors were shown to express more EMMPRIN and uPA compared to dysplastic lesions. The corresponding cell models, SCC-9 and DOK cells, displayed similar expression pattern. In both cell types EMMPRIN upregulated the expression of uPA as well as that of MMP-2 and MMP-9. EMMPRIN treatment led to a significant increase in cell invasion both in the invasive SCC-9 and in the less invasive dysplastic DOK cells, in an MMP and uPA dependent manner. Conclusions Our results suggest that the upregulation of uPA contributes to EMMPRIN's effect in promoting oral tumor invasion.

  7. Corticotropin-releasing factor-overexpressing mice exhibit reduced neuronal activation in the arcuate nucleus and food intake in response to fasting.

    Science.gov (United States)

    Stengel, Andreas; Goebel, Miriam; Million, Mulugeta; Stenzel-Poore, Mary P; Kobelt, Peter; Mönnikes, Hubert; Taché, Yvette; Wang, Lixin

    2009-01-01

    Corticotropin-releasing factor (CRF) overexpressing (OE) mice are a genetic model that exhibits features of chronic stress. We investigated whether the adaptive feeding response to a hypocaloric challenge induced by food deprivation is impaired under conditions of chronic CRF overproduction. Food intake response to a 16-h overnight fast and ip injection of gut hormones regulating food intake were compared in CRF-OE and wild type (WT) littermate mice along with brain Fos expression, circulating ghrelin levels, and gastric emptying of a nonnutrient meal. CRF-OE mice injected ip with saline showed a 47 and 44% reduction of 30-min and 4-h cumulative food intake response to an overnight fast, respectively, compared with WT. However, the 30-min food intake decrease induced by ip cholecystokinin (3 microg/kg) and increase by ghrelin (300 microg/kg) were similar in CRF-OE and WT mice. Overnight fasting increased the plasma total ghrelin to similar levels in CRF-OE and WT mice, although CRF-OE mice had a 2-fold reduction of nonfasting ghrelin levels. The number of Fos-immunoreactive cells induced by fasting in the arcuate nucleus was reduced by 5.9-fold in CRF-OE compared with WT mice whereas no significant changes were observed in other hypothalamic nuclei. In contrast, fasted CRF-OE mice displayed a 5.6-fold increase in Fos-immunoreactive cell number in the dorsal motor nucleus of the vagus nerve and a 34% increase in 20-min gastric emptying. These findings indicate that sustained overproduction of hypothalamic CRF in mice interferes with fasting-induced activation of arcuate nucleus neurons and the related hyperphagic response.

  8. Overexpression of activated phospholipase Cγ1 is a risk factor for distant metastases in T1-T2, N0 breast cancer patients undergoing adjuvant chemotherapy.

    Science.gov (United States)

    Lattanzio, Rossano; Marchisio, Marco; La Sorda, Rossana; Tinari, Nicola; Falasca, Marco; Alberti, Saverio; Miscia, Sebastiano; Ercolani, Cristiana; Di Benedetto, Anna; Perracchio, Letizia; Melucci, Elisa; Iacobelli, Stefano; Mottolese, Marcella; Natali, Pier Giorgio; Piantelli, Mauro

    2013-03-01

    Phospholipase Cγ1 (PLCγ1) is highly expressed in several tumors. We have previously reported that both stable and inducible PLCγ1 down-regulation resulted in an almost complete inhibition of breast cancer-derived experimental lung metastasis formation. The aim of our study is to evaluate the association between the expression of PLCγ1 and of PLCγ1 phosphorylated at Tyr1253 (PLCγ1-pY1253) and at Tyr783 (PLCγ1-pY783) with the clinical outcome of patients with node negative, T1/T2 breast cancers. The study groups consisted of 292 (training set) and 122 (validation set) patients presenting with primary unilateral breast carcinoma (T1-T2), with no evidence of nodal involvement and distant metastases. PLCγ1, PLCγ1-pY1253 and PLCγ1-pY783 protein expression were assessed by immunohistochemistry on tissue microarrays and the results correlated with the clinical data using Kaplan-Meier curves and multivariate Cox regression analysis. Tumor cells while expressing variable proportions of cytoplasmic PLCγ1, express PLCγ1-pY1253 and PLCγ1-pY783 predominantly in the nucleus. High expression of PLCγ1, and of its activated forms, is associated with a worse clinical outcome in terms of incidence of distant metastases, and not of local relapse in T1-T2, N0 breast cancer patients undergone adjuvant chemotherapy. PLCγ1 over-expression appears to be a reliable predictive surrogate marker of development of metastases. Thus, targeting PLCγ1 pathways might represent a potential therapeutic approach for the prevention of metastatic disease in breast cancer.

  9. miR-155 Over-expression Promotes Genomic Instability by Reducing High-fidelity Polymerase Delta Expression and Activating Error-prone DSB Repair

    Science.gov (United States)

    Czochor, Jennifer R.; Sulkowski, Parker; Glazer, Peter M.

    2016-01-01

    miR-155 is an oncogenic microRNA (miR) that is often over-expressed in cancer and is associated with poor prognosis. miR-155 can target several DNA repair factors including RAD51, MLH1, and MSH6, and its over-expression results in an increased mutation frequency in vitro, although the mechanism has yet to be fully understood. Here, we demonstrate that over-expression of miR-155 drives an increased mutation frequency both in vitro and in vivo, promoting genomic instability by affecting multiple DNA repair pathways. miR-155 over-expression causes a decrease in homologous recombination, but yields a concurrent increase in the error-prone non-homologous end-joining (NHEJ) pathway. Despite repressing established targets MLH1 and MSH6, the identified mutation pattern upon miR-155 over-expression does not resemble that of a mismatch repair-deficient background. Further investigation revealed that all four subunits of polymerase delta, a high-fidelity DNA replication and repair polymerase, are down-regulated at the mRNA level in the context of miR-155 over-expression. FOXO3a, a transcription factor and known target of miR-155, has one or more putative binding site(s) in the promoter of all four polymerase delta subunits. Finally, suppression of FOXO3a by miR-155 or by siRNA knockdown is sufficient to repress the expression of the catalytic subunit of polymerase delta, POLD1, at the protein level, indicating that FOXO3a contributes to the regulation of polymerase delta levels. PMID:26850462

  10. Identificación de factores externos que inciden en el fortalecimiento de las unidades productivas asociativas (UPAS en Medellín, Colombia

    Directory of Open Access Journals (Sweden)

    Martha Luz Benjumea Arias

    2015-01-01

    Full Text Available presentan los resultados de la fase I en la que se analizan las percepciones de los emprendedores de 36 unidades productivas asociativas (upas en relación con los factores del entorno. También se exponen las bases metodológicas para el desarrollo de la fase ii que evaluará el impacto social y económico de los emprendedores y las upas a partir del método de comparación reflexiva. Los principales resultados señalan que las mayores dificultades están representadas en los trámites legales, la articulación comercial y la inexistencia de vínculos de asociación, mientras que resaltan positivamente el apoyo del gobierno municipal, la infraestructura física, capacidad de consumo y la identificación de nichos de mercado.

  11. The nicotinic alpha7 acetylcholine receptor agonist ssr180711 is unable to activate limbic neurons in mice overexpressing human amyloid-beta1-42

    DEFF Research Database (Denmark)

    Soderman, A.; Spang-Thomsen, Mogens; Hansen, H.

    2008-01-01

    7 nAChR have not been examined. The aim of this study has been to evaluate the efficacy of alpha7 nAChR modulators in transgene mice that overexpress human amyloid precursor protein and accumulate Abeta1-40 and Abeta1-42. In accordance with observations in human Alzheimer tissues, we show here...

  12. RNA Interference of Interferon Regulatory Factor-1 Gene Expression in THP-1 Cell Line Leads to Toll-Like Receptor-4 Overexpression/Activation As Well As Up-modulation of Annexin-II

    Directory of Open Access Journals (Sweden)

    Christos I. Maratheftis

    2007-12-01

    Full Text Available Interferon regulatory factor-1 (IRF-1 is a candidate transcription factor for the regulation of the Toll-like receptor-4 (TLR-4 gene. Using a small interfering RNAbased (siRNA process to silence IRF-1 gene expression in the leukemic monocytic cell line THP-1, we investigated whether such a modulation would alter TLR-4 expression and activation status in these cells. The siIRF-1 cells expressed elevated levels of TLR-4 mRNA and protein compared to controls by 90% and 77%, respectively. ICAM.1 protein expression and apoptosis levels were increased by 8.35- and 4.25-fold, respectively. The siIRF-1 cells overexpressed Bax mRNA compared to controls. Proteomic analysis revealed upmodulation of the Annexin-II protein in siIRF-1 THP-1 cells. Myelodysplastic syndrome (MDS patients with an absence of full-length IRF-1 mRNA also overexpressed Annexin-II. It is plausible that this overexpression may lead to the activation of TLR-4 contributing to the increased apoptosis characterizing MDS.

  13. Corticotropin-Releasing Factor-Overexpressing Mice Exhibit Reduced Neuronal Activation in the Arcuate Nucleus and Food Intake in Response to Fasting

    OpenAIRE

    2008-01-01

    Corticotropin-releasing factor (CRF) overexpressing (OE) mice are a genetic model that exhibits features of chronic stress. We investigated whether the adaptive feeding response to a hypocaloric challenge induced by food deprivation is impaired under conditions of chronic CRF overproduction. Food intake response to a 16-h overnight fast and ip injection of gut hormones regulating food intake were compared in CRF-OE and wild type (WT) littermate mice along with brain Fos expression, circulatin...

  14. Antitumor activity of a combination of trastuzumab (Herceptin) and oral fluoropyrimidine S-1 on human epidermal growth factor receptor 2-overexpressing pancreatic cancer.

    Science.gov (United States)

    Saeki, Hiroyuki; Yanoma, Shunsuke; Takemiya, Shouji; Sugimasa, Yukio; Akaike, Makoto; Yukawa, Norio; Rino, Yasushi; Imada, Toshio

    2007-08-01

    The cytotoxic effect of trastuzumab in combination with oral fluoropyrimidine S-1 on human epidermal growth factor receptor 2 (HER2)-overexpressing human pancreatic cancer cell line TRG in vitro and in vivo was investigated. HER2 expression in TRG was analyzed by RT-PCR and flow cytometry. For in vitro experiments, 5-fluorouracil (5-FU) was used instead of S-1. In vivo studies were conducted with TRG xenografts in athymic mice. Trastuzumab (10 mg/kg) was administered intraperitoneally once a week for 4 weeks. S-1 (10 mg/kg) was administered orally 5 days a week for 4 weeks. The results showed that TRG cells were positive for HER2 mRNA and overexpressed HER2 protein. Either trastuzumab or 5-FU concentration-dependently inhibited the growth of TRG cells. The combination of trastuzumab and 5-FU resulted in a significant inhibition of growth of TRG cells compared to either agent alone (P<0.001). Incubation of TRG cells with peripheral blood mononuclear cells after treatment with trastuzumab enhanced the antiproliferative effect of trastuzumab, which could be the result of antibody-dependent cellular cytotoxicity. The combination of trastuzumab and S-1 resulted in a significant reduction in xenograft volume compared to each agent alone (P<0.0001). In conclusion, this study showed that combination therapy with trastuzumab and S-1 may be effective for HER2-overexpressing pancreatic cancer patients.

  15. Decreased signaling competence as a result of receptor overexpression: overexpression of CD4 reduces its ability to activate p56lck tyrosine kinase and to regulate T-cell antigen receptor expression in immature CD4+CD8+ thymocytes.

    OpenAIRE

    Nakayama, T.; Wiest, D L; Abraham, K.M.; Munitz, T I; Perlmutter, R M; Singer, A

    1993-01-01

    Thymic selection of the developing T-cell repertoire occurs in immature CD4+CD8+ thymocytes, with the fate of individual thymocytes determined by the specificity of T-cell antigen receptor they express. However, T-cell antigen receptor expression in immature CD4+CD8+ thymocytes is actively down-regulated in CD4+CD8+ thymocytes by CD4-mediated tyrosine kinase signals that are generated in the thymus as a result of CD4 engagement by intrathymic ligands. In the present study we have examined the...

  16. The LysM Receptor-Like Kinase LysM RLK1 Is Required to Activate Defense and Abiotic-Stress Responses Induced by Overexpression of Fungal Chitinases in Arabidopsis Plants

    Institute of Scientific and Technical Information of China (English)

    Yariv Brotman; Ada Viterbo; Udi Landau; Smadar Pnini; Jan Lisec; Salma Balazadeh; Bernd Mueller-Roeber; Aviah Zilberstein; Lothar Willmitzer; Ilan Chet

    2012-01-01

    Application of crab shell chitin or pentamer chitin oligosaccharide to Arabidopsis seedlings increased tolerance to salinity in wild-type but not in knockout mutants of the LysM Receptor-Like Kinase1 (CERK1/LysM RLK1) gene,known to play a critical role in signaling defense responses induced by exogenous chitin.Arabidopsis plants overexpressing the endochitinase chit36 and hexoaminidase excy1 genes from the fungus Trichoderma asperelleoides T203 showed increased tolerance to salinity,heavy-metal stresses,and Botrytis cinerea infection.Resistant lines,overexpressing fungal chitinases at different levels,were outcrossed to lysm rlk1 mutants.Independent homozygous hybrids lost resistance to biotic and abiotic stresses,despite enhanced chitinase activity.Expression analysis of 270 stress-related genes,including those induced by reactive oxygen species (ROS) and chitin,revealed constant up-regulation (at least twofold) of 10 genes in the chitinase-overexpressing line and an additional 76 salt-induced genes whose expression was not elevated in the lysm rlk1 knockout mutant or the hybrids harboring the mutation.These findings elucidate that chitin-induced signaling mediated by LysM RLK1 receptor is not limited to biotic stress response but also encompasses abiotic-stress signaling and can be conveyed by ectopic expression of chitinases in plants.

  17. Anti-tumor activities of luteolin and silibinin in glioblastoma cells: overexpression of miR-7-1-3p augmented luteolin and silibinin to inhibit autophagy and induce apoptosis in glioblastoma in vivo.

    Science.gov (United States)

    Chakrabarti, Mrinmay; Ray, Swapan K

    2016-03-01

    Glioblastoma is the deadliest brain tumor in humans. High systemic toxicity of conventional chemotherapies prompted the search for natural compounds for controlling glioblastoma. The natural flavonoids luteolin (LUT) and silibinin (SIL) have anti-tumor activities. LUT inhibits autophagy, cell proliferation, metastasis, and angiogenesis and induces apoptosis; while SIL activates caspase-8 cascades to induce apoptosis. However, synergistic anti-tumor effects of LUT and SIL in glioblastoma remain unknown. Overexpression of tumor suppressor microRNA (miR) could enhance the anti-tumor effects of LUT and SIL. Here, we showed that 20 µM LUT and 50 µM SIL worked synergistically for inhibiting growth of two different human glioblastoma U87MG (wild-type p53) and T98G (mutant p53) cell lines and natural combination therapy was more effective than conventional chemotherapy (10 µM BCNU or 100 µM TMZ). Combination of LUT and SIL caused inhibition of growth of glioblastoma cells due to induction of significant amounts of apoptosis and complete inhibition of invasion and migration. Further, combination of LUT and SIL inhibited rapamycin (RAPA)-induced autophagy, a survival mechanism, with suppression of PKCα and promotion of apoptosis through down regulation of iNOS and significant increase in expression of the tumor suppressor miR-7-1-3p in glioblastoma cells. Our in vivo studies confirmed that overexpression of miR-7-1-3p augmented anti-tumor activities of LUT and SIL in RAPA pre-treated both U87MG and T98G tumors. In conclusion, our results clearly demonstrated that overexpression of miR-7-1-3p augmented the anti-tumor activities of LUT and SIL to inhibit autophagy and induce apoptosis for controlling growth of different human glioblastomas in vivo.

  18. Construction of a single lentiviral vector containing tetracycline-inducible Alb-uPA for transduction of uPA expression in murine hepatocytes.

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    Jiasi Bai

    Full Text Available The SCID-beige/Alb-uPA mouse model is currently the best small animal model available for viral hepatitis infection studies [1]. But the construction procedure is often costly and time-consuming due to logistic and technical difficulties. Thus, the widespread application of these chimeric mice has been hampered [2]. In order to optimize the procedure, we constructed a single lentiviral vector containing modified tetracycline-regulated system to control Alb-uPA gene expression in the cultured hepatocytes. The modified albumin promoter controlled by tetracycline (Tet-dependent transactivator rtTA2S-M2 was integrated into a lentiviral vector. The full-length uPA cDNA was inserted into another lentiviral vector containing PTight, a modified Tet-responsive promoter. Two vectors were then digested by specific enzymes and ligated by DNA ligase 4. The ligated DNA fragment was inserted into a modified pLKO.1 cloning vector and the final lentiviral vector was then successfully constructed. H2.35 cell, Lewis lung carcinoma, primary kidney, primary hepatic interstitial and CT26 cells were infected with recombinant lentivirus at selected MOI. The expression of uPA induced by DOX was detectable only in the infected H2.35 cells, which was confirmed by real-time PCR and Western blot analysis. Moreover, DOX induced uPA expression on the infected H2.35 cells in a dose-dependent manner. The constructed single lentiviral vector has many biological advantages, including that the interested gene expression under "Tet-on/off" system is controlled by DOX in a dose-depending fashion only in murine liver cells, which provides an advantage for simplifying generation of conditional transgenic animals.

  19. Overexpression of integrin αv facilitates proliferation and invasion of oral squamous cell carcinoma cells via MEK/ERK signaling pathway that is activated by interaction of integrin αvβ8 with type Ⅰ collagen.

    Science.gov (United States)

    Hayashido, Yasutaka; Kitano, Hisataka; Sakaue, Taishi; Fujii, Takahiko; Suematsu, Mirei; Sakurai, Shigeru; Okamoto, Tetsuji

    2014-11-01

    To examine the role of integrin αv subunit in the progression of squamous cell carcinoma (SCC), oral SCC cells were stably transfected with integrin αv cDNA. Integrin αv transfectants exhibited the enhancement of proliferation on type Ⅰ collagen, and seemed to have a high ability to invade type Ⅰ collagen gel. Overexpression of integrin αv led to rapid phosphorylation of focal adhesion kinase (FAK), mitogen‑activated protein kinase kinase 1/2 (MEK1/2) and extracellular signal‑regulated kinase 1/2 (ERK1/2) in SCC cells on type Ⅰ collagen. The downregulation of integrin β8 in integrin αv transfectants by its specific antisense oligonucleotide led to a decrease in type Ⅰ collagen‑stimulated activation of FAK and the MEK/ERK signaling pathway, and also suppressed the proliferation on type Ⅰ collagen and the invasiveness into type Ⅰ collagen gel. Moreover, the expression of integrin β8 was induced following transfection with integrin αv cDNA. These results indicated that the overexpression of integrin αv induces integrin αvβ8 heterodimer formation and the binding of integrin αvβ8 to type Ⅰ collagen might enhance the proliferation and invasion of SCC cells via the activation of the MEK/ERK signaling pathway.

  20. Overexpression of linker for activated T cells, cyclooxygenase-2, CD1a, CD68 and myeloid/histiocyte antigen in an inflamed seborrheic keratosis

    Directory of Open Access Journals (Sweden)

    Ana Maria Abreu-Velez

    2011-01-01

    Full Text Available Context: Inflamed seborrheic keratoses are generally associated with the accumulation of variable numbers of lymphocytes and histiocytes in the superficial dermis. The precise immunologic mechanism of this histologic phenomenon is not known Case Report: A 62-year-old male presented with a patch on the right neck with additional features of inflammation. Skin biopsies for hematoxylin and eosin examination, as well as for immunohistochemistry analysis were performed. Results: H&E staining demonstrated classic features of an inflamed seborrheic keratosis. Overexpression of LAT, COX-2, CD1a, and CD68 was noticed in the inflammatory infiltrate. A strong presence of CD1a was also seen in the epidermis suprajacent to the inflammation. Myeloid/histiocyte antigen was strongly expressed by the keratinocytes . Conclusion : A complex immune response seems to be involved in the pathophysiology of an inflamed seborrheic keratosis.

  1. Reduction of mouse atherosclerosis by urokinase inhibition or with a limited-spectrum matrix metalloproteinase inhibitor

    DEFF Research Database (Denmark)

    Hu, Jie Hong; Touch, Phanith; Zhang, Jingwan;

    2015-01-01

    AIMS: Elevated activity of urokinase plasminogen activator (uPA) and MMPs in human arteries is associated with accelerated atherosclerosis, aneurysms, and plaque rupture. We used Apoe-null mice with macrophage-specific uPA overexpression (SR-uPA mice; a well-characterized model of protease-accele...

  2. Does Council Tax Valuation Band (CTVB correlate with Under-Privileged Area 8 (UPA8 score and could it be a better 'Jarman Index'?

    Directory of Open Access Journals (Sweden)

    Taylor Gordon

    2001-11-01

    Full Text Available Abstract Background Widespread scepticism persists on the use of the Under-Privileged Area (UPA8 score of Jarman in distributing supplementary resources to so-attributed 'deprived' UK general practices. The search for better 'needs' markers continues. Having already shown that Council Tax Valuation Band (CTVB is a predictor of UK GP workload, we compare, here, CTVB of residence of a random sample of patients with their respective 'Jarman' scores. Methods Correlation coefficient is calculated between (i the CTVB of residence of a randomised sample of patients from an English general practice and (ii the UPA8 scores of the relevant enumeration districts in which they live. Results There is a highly significant correlation between the two measures despite modest study size of 478 patients (85% response. Conclusions The proposal that CTVB is a marker of deprivation and of clinical demand should be examined in more detail: it correlates with 'Jarman', which is already used in NHS resource allocation. But unlike 'Jarman', CTVB is simple, objective, and free of the problems of Census data. CTVB, being household-based, can be aggregated at will.

  3. Neurotensin (NTS) and its receptor (NTSR1) causes EGFR, HER2 and HER3 over-expression and their autocrine/paracrine activation in lung tumors, confirming responsiveness to erlotinib.

    Science.gov (United States)

    Younes, Mohamad; Wu, Zherui; Dupouy, Sandra; Lupo, Audrey Mansuet; Mourra, Najat; Takahashi, Takashi; Fléjou, Jean François; Trédaniel, Jean; Régnard, Jean François; Damotte, Diane; Alifano, Marco; Forgez, Patricia

    2014-09-30

    Alterations in the signaling pathways of epidermal growth factor receptors (HERs) are associated with tumor aggressiveness. Neurotensin (NTS) and its high affinity receptor (NTSR1) are up regulated in 60% of lung cancers. In a previous clinical study, NTSR1 overexpression was shown to predict a poor prognosis for 5 year overall survival in a selected population of stage I lung adenocarcinomas treated by surgery alone. In a second study, shown here, the frequent and high expression of NTSR1 was correlated with a pejorative prognosis in 389 patients with stage I to III lung adenocarcinoma, and was an independent prognosis marker. Interactions between NTS and NTSR1 induce pro-oncogenic biological effects associated with neoplastic processes and tumor progression. Here we highlight the cellular mechanisms activated by Neurotensin (NTS) and its high affinity receptor (NTSR1) contributing to lung cancer cell aggressiveness. We show that the NTS autocrine and/or paracrine regulation causes EGFR, HER2, and HER3 over-expression and activation in lung tumor cells. The EGFR and HER3 autocrine activation is mediated by MMP1 activation and EGF "like" ligands (HB-EGF, Neuregulin 1) release. By establishing autocrine and/or paracrine NTS regulation, we show that tumor growth is modulated according to NTS expression, with a low growth rate in those tumors that do not express NTS. Accordingly, xenografted tumors expressing NTS and NTSR1 showed a positive response to erlotinib, whereas tumors void of NTSR1 expression had no detectable response. This is consistent with the presence of a NTS autocrine loop, leading to the sustained activation of EGFR and responsible for cancer aggressiveness. We propose the use of NTS/NTSR1 tumor expression, as a biomarker for the use of EGFR tyrosine kinase inhibitors in patients lacking EGFR mutation.

  4. Camptothecin induces urokinase-type plasminogen activator gene-expression in human RC-K8 malignant lymphoma and H69 small cell lung cancer cells.

    Directory of Open Access Journals (Sweden)

    Shibakura M

    2002-10-01

    Full Text Available We previously reported that anthracyclines, which could generate reactive oxygen species (ROS, could induce the urokinase-type plasminogen activator (uPA gene expression in human RC-K8 malignant lymphoma cells and in H69 small cell lung cancer (SCLC cells. In screening other uPA-inducible anti-cancer agents, we found that camptothecin (CPT and its derivative, SN38, could induce uPA in RC-K8 and H69 cells. CPT and SN38, which are also used for the treatment of lymphoma and SCLC, significantly increased the uPA accumulation in the conditioned media of both cells in a dose-dependent manner. The maximum induction of uPA mRNA levels was observed 24 h after stimulation. Pretreatment with pyrrolidine dithiocarbamate (PDTC, an anti-oxidant, inhibited the CPT-induced uPA mRNA expression. Thus, CPT induces uPA through gene expression, and, therefore, CPT may influence the tumor-cell biology by up-regulating the uPA/plasmin system.

  5. Camptothecin induces urokinase-type plasminogen activator gene-expression in human RC-K8 malignant lymphoma and H69 small cell lung cancer cells.

    Science.gov (United States)

    Shibakura, Misako; Niiya, Kenji; Kiguchi, Toru; Nakata, Yasunari; Tanimoto, Mitsune

    2002-10-01

    We previously reported that anthracyclines, which could generate reactive oxygen species (ROS), could induce the urokinase-type plasminogen activator (uPA) gene expression in human RC-K8 malignant lymphoma cells and in H69 small cell lung cancer (SCLC) cells. In screening other uPA-inducible anti-cancer agents, we found that camptothecin (CPT) and its derivative, SN38, could induce uPA in RC-K8 and H69 cells. CPT and SN38, which are also used for the treatment of lymphoma and SCLC, significantly increased the uPA accumulation in the conditioned media of both cells in a dose-dependent manner. The maximum induction of uPA mRNA levels was observed 24 h after stimulation. Pretreatment with pyrrolidine dithiocarbamate (PDTC), an anti-oxidant, inhibited the CPT-induced uPA mRNA expression. Thus, CPT induces uPA through gene expression, and, therefore, CPT may influence the tumor-cell biology by up-regulating the uPA/plasmin system.

  6. Overexpression of S-adenosylmethionine decarboxylase (SAMDC) in Xenopus embryos activates maternal program of apoptosis as a "fail-safe" mechanism of early embryogenesis

    Institute of Scientific and Technical Information of China (English)

    MASATAKE KAI; CHIKARA KAITO; HIROSHI FUKAMACHI; TAKAYASU HIGO; EIJI TA-KAYAMA; HIROSHI HARA; YOSHIKAZU OHYA; KAZUEI IGARASHI; KOICHIRO SHIOKAWA

    2003-01-01

    In Xenopus, injection of S-adenosylmethionine decarboxylase (SAMDC) mRNA into fertilized eggs or2-cell stage embryos induces massive cell dissociation and embryo-lysis at the early gastrula stage due toactivation of the maternal program of apoptosis. We injected SAMDC mRNA into only one of the animalside blastomeres of embryos at different stages of cleavage, and examined the timing of the onset of theapoptotic reaction. In the injection at 4- and 8-cell stages, a considerable number of embryos developed intotadpoles and in the injection at 16- and 32-cell stages, all the embryos became tadpoles, although tadpolesobtained were sometimes abnormal. However, using GFP as a lineage tracer, we found that descendant cellsof the blastomere injected with SAMDC mRNA at 8- to 32-cell stages are confined within the blastocoel atthe early gastrula stage and undergo apoptotic cell death within the blastocoel, in spite of the continueddevelopment of the injected embryos. These results indicate that cells overexpressed with SAMDC undergoapoptotic cell death consistently at the early gastrula stage, irrespective of the timing of the mRNA injection.We assume that apoptosis is executed in Xenopus early gastrulae as a "fail-safe" mechanism to eliminatephysiologically-severely damaged cells to save the rest of the embryo.

  7. Uncharged isocoumarin-based inhibitors of urokinase-type plasminogen activator

    Directory of Open Access Journals (Sweden)

    Deck Lorraine M

    2006-02-01

    Full Text Available Abstract Background Urokinase-type plasminogen activator (uPA plays a major role in extracellular proteolytic events associated with tumor cell growth, migration and angiogenesis. Consequently, uPA is an attractive target for the development of small molecule active site inhibitors. Most of the recent drug development programs aimed at nonpeptidic inhibitors targeted at uPA have focused on arginino mimetics containing amidine or guanidine functional groups attached to aromatic or heterocyclic scaffolds. There is a general problem of limited bioavailability of these charged inhibitors. In the present study, uPA inhibitors were designed on an isocoumarin scaffold containing uncharged substituents. Results 4-Chloro-3-alkoxyisocoumarins were synthesized in which the 3-alkoxy group contained a terminal bromine; these were compared with similar inhibitors that contained a charged terminal functional group. Additional variations included functional groups attached to the seven position of the isocoumarin scaffold. N- [3-(3-Bromopropoxy-4-chloro-1-oxo-1H-isochromen-7-yl]benzamide was identified as an uncharged lead inhibitor of uPA, Ki = 0.034 μM. Molecular modeling of human uPA with these uncharged inhibitors suggests that the bromine occupies the same position as positively charged arginino mimetic groups. Conclusion This study demonstrates that potent uncharged inhibitors of uPA can be developed based upon the isocoumarin scaffold. A tethered bromine in the three position and an aromatic group in the seven position are important contributors to binding. Although the aim was to develop compounds that act as mechanism-based inactivators, these inhibitors are competitive reversible inhibitors.

  8. Immunohistochemical localization of urokinase-type plasminogen activator, urokinase-type plasminogen activator receptor and α2-antiplasmin in human corneal perforation: a case report

    Directory of Open Access Journals (Sweden)

    Sugioka Koji

    2012-11-01

    Full Text Available Abstract Background Corneal ulceration leading to perforation is associated with infectious and non-infectious destructive conditions in the cornea. The fibrinolytic (plasminogen/plasmin system is considered to contribute to tissue remodeling in the wound healing process and it is believed to play an important role in proteolysis and fibrosis. To determine the localization of urokinase-type plasminogen activator (u-PA, u-PA receptor (u-PAR and α2-antiplasmin (α2AP in the tissue of a corneal perforation, we investigated immunohistochemical expressions of u-PA, u-PAR, α2AP, CD68, and α-smooth muscle actin (α-SMA in a patient with corneal perforation that developed from an ulcer of no clear cause. Case presentation The patient was a 77-year-old woman who presented with a perforated corneal ulcer in her right eye. The cause of her corneal ulcer was unknown. Double immunohistochemistry was performed for the combinations of u-PA with u-PAR, CD68 or α-SMA and α2AP with CD68 or α-SMA to detect the localization of u-PA and α2AP. u-PA and u-PAR co-localization was seen in the corneal ulceration area. u-PA was mainly observed in CD68-positive cells and in some α-SMA positive cells. On the other hand, α2AP was not expressed in CD68-positive cells, but was expressed in α-SMA positive cells. Conclusion We identified expression of the u-PA/u-PAR complex and α2AP in a patient with a corneal ulcer. These two molecules are believed to play a crucial role in inflammatory cell recruitment, ECM synthesis and degradation during corneal wound healing.

  9. Urokinase-type plasminogen activator deficiency has little effect on seizure susceptibility and acquired epilepsy phenotype but reduces spontaneous exploration in mice.

    Science.gov (United States)

    Rantala, J; Kemppainen, S; Ndode-Ekane, X E; Lahtinen, L; Bolkvadze, Tamuna; Gurevicius, K; Tanila, H; Pitkänen, A

    2015-01-01

    Urokinase-type plasminogen activator (uPA), a serine protease, converts plasminogen to plasmin. Activation of plasmin leads to degradation of the extracellular matrix, which is critical for tissue recovery, angiogenesis, cell migration, and axonal and synaptic plasticity. We hypothesized that uPA deficiency would cause an abnormal neurophenotype and would lead to exacerbated epileptogenesis after brain injury. Wild-type (Wt) and uPA-/- mice underwent a battery of neurologic behavioral tests evaluating general reactivity, spontaneous exploratory activity, motor coordination, pain threshold, fear and anxiety, and memory. We placed particular emphasis on the effect of uPA deficiency on seizure susceptibility, including the response to convulsants (pentylenetetrazol, kainate, or pilocarpine) and kainate-induced epileptogenesis and epilepsy. The uPA-/- mice showed no motor or sensory impairment compared with the Wt mice. Hippocampus-dependent spatial memory also remained intact. The uPA-/- mice, however, exhibited reduced exploratory activity and an enhanced response to a tone stimulus (p<0.05 compared with the Wt mice). The urokinase-type plasminogen activator deficient mice showed no increase in spontaneous or evoked epileptiform electrographic activity. Rather, the response to pilocarpine administration was reduced compared with the Wt mice (p<0.05). Also, the epileptogenesis and the epilepsy phenotype after intrahippocampal kainate injection were similar to those in the Wt mice. Taken together, uPA deficiency led to diminished interest in the environmental surroundings and enhanced emotional reactivity to unexpected aversive stimuli. Urokinase-type plasminogen activator deficiency was not associated with enhanced seizure susceptibility or worsened poststatus epilepticus epilepsy phenotype.

  10. Overexpression of activin-A and -B in malignant mesothelioma – Attenuated Smad3 signaling responses and ERK activation promote cell migration and invasive growth

    Energy Technology Data Exchange (ETDEWEB)

    Tamminen, Jenni A.; Yin, Miao [Research Programs Unit, Translational Cancer Biology, University of Helsinki (Finland); Transplantation Laboratory, Haartman Institute, University of Helsinki (Finland); Rönty, Mikko [Helsinki University Central Hospital Laboratory, Helsinki (Finland); Department of Pathology, University of Helsinki (Finland); Sutinen, Eva [Helsinki University Central Hospital Laboratory, Helsinki (Finland); Department of Medicine, Division of Pulmonary Medicine, University of Helsinki (Finland); Pasternack, Arja; Ritvos, Olli [Helsinki University Central Hospital Laboratory, Helsinki (Finland); Department of Bacteriology and Immunology, University of Helsinki (Finland); Myllärniemi, Marjukka [Transplantation Laboratory, Haartman Institute, University of Helsinki (Finland); Helsinki University Central Hospital Laboratory, Helsinki (Finland); Department of Medicine, Division of Pulmonary Medicine, University of Helsinki (Finland); Koli, Katri, E-mail: katri.koli@helsinki.fi [Research Programs Unit, Translational Cancer Biology, University of Helsinki (Finland); Transplantation Laboratory, Haartman Institute, University of Helsinki (Finland)

    2015-03-01

    Activin-A and activin-B, members of the TGF-β superfamily, are regulators of reproductive functions, inflammation and wound healing. These dimeric molecules regulate various cellular activities such as proliferation, migration and suvival. Malignant mesothelioma is an asbestos exposure related tumor affecting mainly pleura and it usually has a dismal prognosis. Here, we demonstrate that both activin-A and -B are abundantly expressed in mesothelioma tumor tissue as well as in cultured primary and established mesothelioma cells. Migratory and invasive mesothelioma cells were also found to have attenuated activation of the Smad2/3 pathway in response to activins. Migration and invasive growth of the cells in three-dimentional matrix was prevented by inhibition of activin activity using a soluble activin receptor 2B (sActR2B-Fc). This was associated with decreased ERK activity. Furthermore, migration and invasive growth was significantly inhibited by blocking ERK phosphorylation. Mesothelioma tumors are locally invasive and our results clearly suggest that acivins have a tumor-promoting function in mesothelioma through increasing expression and switching from canonical Smad3 pathway to non-canonical ERK pathway signaling. Blocking activin activity offers a new therapeutic approach for inhibition of mesothelioma invasive growth. - Highlights: • Activin-A and activin-B are highly expressed in mesothelioma. • Mesothelioma cell migration and invasive growth can be blocked with sActR2B. • Activin induced Smad3 activity is attenuated in invasive mesothelioma cells. • Activins induce ERK activity in mesothelioma cells.

  11. PEITC inhibits human brain glioblastoma GBM 8401 cell migration and invasion through the inhibition of uPA, Rho A, and Ras with inhibition of MMP-2, -7 and -9 gene expression.

    Science.gov (United States)

    Chou, Yu-Cheng; Chang, Meng-Ya; Wang, Mei-Jen; Yu, Fu-Shun; Liu, Hsin-Chung; Harnod, Tomor; Hung, Chih-Huang; Lee, Hsu-Tung; Chung, Jing-Gung

    2015-11-01

    Glioblastoma is the most aggressive primary brain malignancy, and the efficacy of multimodality treatments remains unsatisfactory. Phenethyl isothiocyanate (PEITC), one member of the isothiocyanate family, was found to inhibit the migration and invasion of many types of human cancer cells. In our previous study, PEITC induced the apoptosis of human brain glioblastoma GBM 8401 cells through the extrinsic and intrinsic signaling pathways. In the present study, we first investigated the effects of PEITC on the migration and invasion of GBM 8401 cells. PEITC decreased the migration of GBM 8401 cells in a dose-dependent manner as determined from scratch wound healing and Transwell migration assays. The percentage of inhibition ranged from 46.89 to 15.75%, and from 27.80 to 7.31% after a 48-h treatment of PEITC as determined from the Transwell migration assay and invasion assay, respectively. The western blot analysis indicated that PEITC decreased the levels of proteins associated with migration and invasion, Ras, uPA, RhoA, GRB2, p-p38, p-JNK, p-ERK, p65, SOS1, MMP-2, MMP-9 and MMP-13, in a dose-dependent manner. Real-time PCR analyses revealed that PEITC reduced the mRNA levels of MMP-2, MMP-7, MMP-9 and RhoA in a dose- and time-dependent manner. PEITC exhibited potent anticancer activities through the inhibition of migration and invasion in the GBM 8401 cells. Our findings elucidate the possible molecular mechanisms and signaling pathways of the anti-metastatic effects of PEITC on human brain glioblastoma cells, and PEITC may be considered as a therapeutic agent.

  12. High nuclear grade, frequent mitotic activity, cyclin D1 and p53 overexpression are associated with stromal invasion in mammary intracystic papillary carcinoma.

    Science.gov (United States)

    Zhang, Cunxian; Zhang, Peng; Hao, Jie; Quddus, M Ruhul; Steinhoff, Margaret M; Sung, C James

    2005-01-01

    Stromal invasion is identified with difficulty in routine hematoxylin-eosin-stained sections of core needle biopsy specimens from mammary intracystic papillary carcinomas. The goal of this study was to determine if nuclear grade, mitotic activity, and immunohistochemical stains for p53 and cyclin D1 would assist in differentiating intracystic papillary carcinomas without stromal invasion (ICPC) from tumors with stromal invasion (ICPC-INVA). Eight cases of ICPC and 12 cases of ICPC-INVA were reviewed. Hematoxylin-eosin slides were examined to determine the histologic features. Immunohistochemistry was performed using monoclonal antibodies to human p53 and cyclin D1. Fisher's exact test was used to compare the nuclear grade, mitotic activity, and immunoreactivity between ICPC and ICPC-INVA. High nuclear grade was more often associated with ICPC-INVA than with ICPC, although the difference was not statistically significant (p = 0.069). Frequent mitotic activity was associated with ICPC-INVA more than with ICPC (p = 0.0198). All cases of ICPC were negative for either p53 or cyclin D1, whereas 7 of 12 cases (58.3%) of ICPC-INVA were positive for either cyclin D1 alone (3 cases), p53 alone (3 cases), or both cyclin D1 and p53 (1 case) (p = 0.0147). Identical nuclear grade, mitotic activity, and immunostaining patterns were seen in the intracystic and the invasive components, and in the core biopsy and the excision of the same tumor. When any one of the positive indicators (high nuclear grade, frequent mitotic activity, or positive immunostains for cyclin D1 and/or p53) was present, the positive predictive value for stromal invasion was 91.7%. When none of the positive indicators was present, the negative predictive value was 87.5%.

  13. Electroanalysis of pM-levels of urokinase plasminogen activator in serum by phosphorothioated RNA aptamer.

    Science.gov (United States)

    Jarczewska, Marta; Kékedy-Nagy, László; Nielsen, Jesper S; Campos, Rui; Kjems, Jørgen; Malinowska, Elżbieta; Ferapontova, Elena E

    2015-06-01

    Protein biomarkers of cancer allow a dramatic improvement in cancer diagnostics as compared to the traditional histological characterisation of tumours by enabling a non-invasive analysis of cancer development and treatment. Here, an electrochemical label-free assay for urokinase plasminogen activator (uPA), a universal biomarker of several cancers, has been developed based on the recently selected uPA-specific fluorinated RNA aptamer, tethered to a gold electrode via a phosphorothioated dA tag, and soluble redox indicators. The binding properties of the uPA-aptamer couple and interference from the non-specific adsorption of bovine serum albumin (BSA) were modulated by the electrode surface charge. A nM uPA electroanalysis at positively charged surfaces, complicated by the competitive adsorption of BSA, was tuned to the pM uPA analysis at negative surface charges of the electrode, being improved in the presence of negatively charged BSA. The aptamer affinity for uPA displayed via the binding/dissociation constant relationship correspondingly increased, ca. three orders of magnitude, from 0.441 to 367. Under optimal conditions, the aptasensor allowed 10(-12)-10(-9) M uPA analysis, also in serum, being practically useful for clinical applications. The proposed strategy for optimization of the electrochemical protein sensing is of particular importance for the assessment and optimization of in vivo protein ligand binding by surface-tethered aptamers.

  14. Gene expression of fibrinolytic factors urokinase plasminogen activator and plasminogen activator inhibitor-1 in rabbit temporo-mandibular joint cartilage with disc displacement

    Institute of Scientific and Technical Information of China (English)

    ZHAN Jing; GU Zhi-yuan; WU Li-qun; ZHANG Yin-kai; HU Ji-an

    2005-01-01

    Background The urokinase plasminogen activator system is believed to play an important role in degradation of the extracellular matrix associated with cartilage and bone destruction; however its precise roles in temporomandibular disorders have not yet been clarified. The aims of this study were to investigate the gene expression of fibrinolytic factors urokinase plasminogen activator (uPA) and plasminogen activator inhibitor-1 (PAI-1) in the articular cartilage of rabbit temporomandibular joint (TMJ) with disc displacement (DD) and to probe the relationship between fibrinolytic activity and cartilage remodeling. Methods Disc displacement of right joints was performed in 36 of 78 rabbits under investigation. The animals were sacrificed at 4 days and 1, 2, 4, 8 and 12 weeks after surgery, respectively. The right joints of these animals were harvested and processed for the examination of mRNA expression of uPA and PAI-1 in articular cartilage using in situ hybridization techniques. Results The expression of uPA and PAI-1 was co-expressed weakly in the chondrocytes from transitive zone to hypertrophic zone and mineralized zone, while no hybridizing signals were shown in proliferative zone and superficial zone in control rabbits. The most striking was the up-regulation of uPA and PAI-1 mRNA in 4-day rabbits postoperatively at the onset of cartilage degeneration. The strongest hybridizing signals for uPA and PAI-1 were seen in 2-week rabbits postoperatively. After 2 weeks, the expression of uPA and PAI-1 began to decrease and reached nearly normal level at 12 weeks. Conclusions The expression of the uPA/PAI-1 system coincides with the pathological changes in condylar cartilage after DD. The uPA/PAI-1 system may be one of the essential mediators in articular cartilage remodeling.

  15. Increases of ferrous iron oxidation activity and arsenic stressed cell growth by overexpression of Cyc2 in Acidithiobacillus ferrooxidans ATCC19859.

    Science.gov (United States)

    Liu, Wei; Lin, Jianqun; Pang, Xin; Mi, Shuang; Cui, Shuang; Lin, Jianqiang

    2013-01-01

    Acidithiobacillus ferrooxidans plays an important role in bioleaching in reproducing the mineral oxidant of ferric iron (Fe(3+) ) by oxidization of ferrous iron (Fe(2+) ). The high-molecular-weight c-type cytochrome Cyc2 that is located in the external membrane is postulated as the first electron carrier in the Fe(2+) oxidation respiratory pathway of A. ferrooxidans. To increase ferrous iron oxidation activity, a recombinant plasmid pTCYC2 containing cyc2 gene under the control of Ptac promoter was constructed and transferred into A. ferrooxidans ATCC19859. The transcriptional level of cyc2 gene was increased by 2.63-fold and Cyc2 protein expression was observed in the recombinant strain compared with the control. The ferrous iron oxidation activity and the arsenic stressed cell growth of the recombinant strain were also elevated.

  16. Overexpression of phyA and appA genes improves soil organic phosphorus utilisation and seed phytase activity in Brassica napus.

    Directory of Open Access Journals (Sweden)

    Yi Wang

    Full Text Available Phytate is the major storage form of organic phosphorus in soils and plant seeds, and phosphorus (P in this form is unavailable to plants or monogastric animals. In the present study, the phytase genes phyA and appA were introduced into Brassica napus cv Westar with a signal peptide sequence and CaMV 35S promoter, respectively. Three independent transgenic lines, P3 and P11 from phyA and a18 from appA, were selected. The three transgenic lines exhibited significantly higher exuded phytase activity when compared to wild-type (WT controls. A quartz sand culture experiment demonstrated that transgenic Brassica napus had significantly improved P uptake and plant biomass. A soil culture experiment revealed that seed yields of transgenic lines P11 and a18 increased by 20.9% and 59.9%, respectively, when compared to WT. When phytate was used as the sole P source, P accumulation in seeds increased by 20.6% and 46.9% with respect to WT in P11 and a18, respectively. The P3 line accumulated markedly more P in seeds than WT, while no significant difference was observed in seed yields when phytate was used as the sole P source. Phytase activities in transgenic canola seeds ranged from 1,138 to 1,605 U kg(-1 seeds, while no phytase activity was detected in WT seeds. Moreover, phytic acid content in P11 and a18 seeds was significantly lower than in WT. These results introduce an opportunity for improvement of soil and seed phytate-P bioavailability through genetic manipulation of oilseed rape, thereby increasing plant production and P nutrition for monogastric animals.

  17. Induction of caspase-dependent extrinsic apoptosis by apigenin through inhibition of signal transducer and activator of transcription 3 (STAT3) signalling in HER2-overexpressing BT-474 breast cancer cells.

    Science.gov (United States)

    Seo, Hye-Sook; Jo, Jae Kyung; Ku, Jin Mo; Choi, Han-Seok; Choi, Youn Kyung; Woo, Jong-Kyu; Kim, Hyo In; Kang, Soo-Yeon; Lee, Kang Min; Nam, Koong Won; Park, Namkyu; Jang, Bo-Hyoung; Shin, Yong Cheol; Ko, Seong-Gyu

    2015-10-23

    Phytoestrogen intake is known to be beneficial to decrease breast cancer incidence and progression. But its molecular mechanisms of action are still unknown. The present study aimed to examine the effect of apigenin on proliferation and apoptosis in HER2-expressing breast cancer cells. In our experiments, apigenin inhibited the proliferation of BT-474 cells in a dose- and time-dependent manner. Apigenin also inhibited clonogenic survival (anchorage-dependent and -independent) of BT-474 cells in a dose-dependent manner. These growth inhibitions were accompanied with an increase in sub-G0/G1 apoptotic populations. Apigenin-induced extrinsic a caspase-dependent apoptosis up-regulating the levels of cleaved caspase-8 and cleaved caspase-3, and inducing the cleavage of poly (ADP-ribose) polymerase (PARP). Whereas, apigenin did not induce apoptosis via intrinsic mitochondrial apoptosis pathway since this compound did not decrease mitochondrial membrane potential without affecting the levels of B-cell lymphoma 2 (Bcl-2) and Bcl-2-associated X protein (BAX). Apigenin reduced the expression of phospho-JAK1, phospho-JAK2 and phospho-STAT3 and decreased signal transducer and activator of transcription 3 (STAT3) dependent luciferase reporter gene activity in BT-474 cells. Apigenin inhibited CoCl2-induced VEGF secretion and decreased the nuclear translocation of STAT3. Our study indicates that apigenin induces apoptosis through inhibition of STAT3 signalling and could serve as a useful compound to prevent or treat HER2-overexpressing breast cancer.

  18. Overexpression of cyclooxygenase-2 in malignant peripheral nerve sheath tumor and selective cyclooxygenase-2 inhibitor-induced apoptosis by activating caspases in human malignant peripheral nerve sheath tumor cells.

    Directory of Open Access Journals (Sweden)

    Michiyuki Hakozaki

    Full Text Available BACKGROUND: Cyclooxygenase-2 (COX-2 is a key enzyme in the conversion of arachidonic acid to prostanoids, and its activation is associated with carcinogenesis as well as inflammation. The antitumor effect of selective COX-2 inhibitors has been noted in various malignancies. Malignant peripheral nerve sheath tumor (MPNST is a rare and aggressive soft tissue sarcoma for which effective treatments have not yet been established. The purpose of this study was to investigate a potential therapeutic role of COX-2 in MPNST. METHODS: We evaluated the expression of COX-2 in 44 cases of high-grade MPNST using immunohistochemical staining and compared the staining results with the characteristics and outcome of the patients. We also investigated the antitumor effect of etodolac, a selective COX-2 inhibitor, on MPNST cells in vitro using the MPNST cell line, FMS-1. RESULTS: Overexpression of COX-2 (≥50% positive cells was observed in 29 cases (65.9%, was significantly associated with a poor overall survival (P = 0.0495, and was considered an independent risk factor for a poor outcome by the results of both univariate and multivariate analysis. Etodolac induced apoptosis of FMS-1 cells through the activation of caspase-8, -9, and -3. Moreover, several caspase inhibitors significantly inhibited etodolac-induced apoptosis. CONCLUSIONS: Selective COX-2 inhibitors including etodolac had an antitumor effect on MPNST cells, and their use holds promise as a novel therapeutic strategy for patients with MPNST to improve their prognoses.

  19. The pro-urokinase plasminogen-activation system in the presence of serpin-type inhibitors and the urokinase receptor

    DEFF Research Database (Denmark)

    Behrendt, Niels; List, Karin; Andreasen, Peter A;

    2003-01-01

    The reciprocal pro-enzyme activation system of plasmin, urokinase-type plasminogen activator (uPA) and their respective zymogens is a potent mechanism in the generation of extracellular proteolytic activity. Plasminogen activator inhibitor type 1 (PAI-1) acts as a negative regulator. This system ...

  20. Ovulation efficiency is reduced in mice that lack plasminogen activator gene function: functional redundancy among physiological plasminogen activators.

    Science.gov (United States)

    Leonardsson, G; Peng, X R; Liu, K; Nordström, L; Carmeliet, P; Mulligan, R; Collen, D; Ny, T

    1995-01-01

    Several lines of indirect evidence suggest that plasminogen activation plays a crucial role in degradation of the follicular wall during ovulation. However, single-deficient mice lacking tissue-type plasminogen activator (tPA), urokinase-type plasminogen activator (uPA), or PA inhibitor type 1(PAI-1) gene function were recently found to have normal reproduction, although mice with a combined deficiency of tPA and uPA were significantly less fertile. To investigate whether the reduced fertility of mice lacking PA gene function is due to a reduced ovulation mechanism, we have determined the ovulation efficiency in 25-day-old mice during gonadotropin-induced ovulation. Our results reveal that ovulation efficiency is normal in mice with a single deficiency of tPA or uPA but reduced by 26% in mice lacking both physiological PAs. This result suggests that plasminogen activation plays a role in ovulatory response, although neither tPA nor uPA individually or in combination is obligatory for ovulation. The loss of an individual PA seems to be functionally complemented by the remaining PA but this compensation does not appear to involve any compensatory up-regulation. Our data imply that a functionally redundant mechanism for plasmin formation operates during gonadotropin-induced ovulation and that PAs together with other proteases generate the proteolytic activity required for follicular wall degradation. Images Fig. 3 Fig. 4 PMID:8618918

  1. The nicotinic alpha7 acetylcholine receptor agonist ssr180711 is unable to activate limbic neurons in mice overexpressing human amyloid-beta1-42

    DEFF Research Database (Denmark)

    Søderman, Andreas; Thomsen, Morten Skøtt; Hansen, Henrik H;

    2008-01-01

    Recent studies have demonstrated that amyloid-beta1-42 (Abeta1-42) binds to the nicotinergic alpha7 acetylcholine receptor (alpha7 nAChR) and that the application of Abeta1-42 to cells inhibits the function of the alpha7 nAChR. The in vivo consequences of the pharmacological activation of the alpha...... through the use of co-immunoprecipitation that human Abeta-immunoreactive peptides bind to mice alpha7 nAChR in vivo. Agonists of the alpha7 nAChR improve memory and attentional properties and increase immediate early gene expression in the prefrontal cortex and the nucleus accumbens. We show that acute...

  2. Combinatorial method for overexpression of membrane proteins in Escherichia coli.

    Science.gov (United States)

    Leviatan, Shani; Sawada, Keisuke; Moriyama, Yoshinori; Nelson, Nathan

    2010-07-30

    Membrane proteins constitute 20-30% of all proteins encoded by the genome of various organisms. Large amounts of purified proteins are required for activity and crystallization attempts. Thus, there is an unmet need for a heterologous membrane protein overexpression system for purification, crystallization, and activity determination. We developed a combinatorial method for overexpressing and purifying membrane proteins using Escherichia coli. This method utilizes short hydrophilic bacterial proteins, YaiN and YbeL, fused to the ends of the membrane proteins to serve as facilitating factors for expression and purification. Fourteen prokaryotic and mammalian membrane proteins were expressed using this system. Moderate to high expression was obtained for most proteins, and detergent solubilization combined with a short purification process produced stable, monodispersed membrane proteins. Five of the mammalian membrane proteins, overexpressed using our system, were reconstituted into liposomes and exhibited transport activity comparable with the native transporters.

  3. Combinatorial Method for Overexpression of Membrane Proteins in Escherichia coli*

    Science.gov (United States)

    Leviatan, Shani; Sawada, Keisuke; Moriyama, Yoshinori; Nelson, Nathan

    2010-01-01

    Membrane proteins constitute 20–30% of all proteins encoded by the genome of various organisms. Large amounts of purified proteins are required for activity and crystallization attempts. Thus, there is an unmet need for a heterologous membrane protein overexpression system for purification, crystallization, and activity determination. We developed a combinatorial method for overexpressing and purifying membrane proteins using Escherichia coli. This method utilizes short hydrophilic bacterial proteins, YaiN and YbeL, fused to the ends of the membrane proteins to serve as facilitating factors for expression and purification. Fourteen prokaryotic and mammalian membrane proteins were expressed using this system. Moderate to high expression was obtained for most proteins, and detergent solubilization combined with a short purification process produced stable, monodispersed membrane proteins. Five of the mammalian membrane proteins, overexpressed using our system, were reconstituted into liposomes and exhibited transport activity comparable with the native transporters. PMID:20525689

  4. DLL4 overexpression increases gastric cancer stem/progenitor cell self-renewal ability and correlates with poor clinical outcome via Notch-1 signaling pathway activation.

    Science.gov (United States)

    Miao, Zhi-Feng; Xu, Hao; Xu, Hui-Mian; Wang, Zhen-Ning; Zhao, Ting-Ting; Song, Yong-Xi; Xu, Ying-Ying

    2017-01-01

    Gastric cancer is one of the most common malignant diseases, and poses a serious threat to the quality of human life. Gastric cancer stem/progenitor cells (GCSPCs) have critical effects on tumor formation, affecting specific features of self-renewal and differentiation and playing a critical role in metastasis. The Notch-1 pathway is crucially important to GCSPCs and is regulated by DLL4. In this study, DLL4 and Nestin levels were measured in 383 gastric cancer tissue samples by immunohistochemistry, and the clinico-pathological features of patients assessed. After DLL4 silencing in selected gastric cancer cell lines, the expression of GCSPC markers and colony formation ability were analyzed and the self-renewal and differentiation capacities of the cells were evaluated. The relationship between DLL4 levels and Notch-1 signaling pathway effector amounts was assessed via Western blotting and immunofluorescence. Finally, the tumor formation ability of the gastric cancer cells was evaluated with different levels of DLL4 and multiple cell densities in vivo. Our results indicate that DLL4 expression is associated with TNM stage and cancer metastasis, with high amounts of DLL4 leading to poor outcome. DLL4 silencing inhibited the self-renewal ability of GCSPCs and increased their multidifferentiation capacity, resulting in reduced GCSPC ratios. DLL4 knockdown also blocked the Notch-1 pathway, weakening invasion ability and resistance to 5-FU chemotherapy. In vivo, DLL4 silencing inhibited the tumor formation ability of GCSPCs. In conclusion, DLL4 affects GCSPC stemness, altering their pathological behavior. DLL4 silencing inhibits GCSPC metastatic potential both in vitro and in vivo by impeding Notch-1 signaling pathway activation, indicating that DLL4 may be a new potential therapeutic target.

  5. Over-expression of TRIM37 promotes cell migration and metastasis in hepatocellular carcinoma by activating Wnt/β-catenin signaling

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Jianxin; Yu, Chao; Chen, Meiyuan; Tian, She; Sun, Chengyi, E-mail: chenyisun11@163.com

    2015-09-04

    Hepatocellular carcinoma (HCC) is the most common cancer in the world especially in East Asia and Africa. Advanced stage, metastasis and frequent relapse are responsible for the poor prognosis of HCC. However, the precise mechanisms underlying HCC remained unclear. So it is urgent to identify the pathological processes and relevant molecules of HCC. TRIM37 is an E3 ligase and has been observed deregulated expression in various tumors. Recent studies of TRIM37 have implicated that TRIM37 played critical roles in cell proliferation and other processes. In the present study, we demonstrated that TRIM37 expression was notably up-regulated in HCC samples and was associated with advanced stage and tumor volume, which all indicating the poor outcomes. We also found that TRIM37 could serve as an independent prognostic factor of HCC. During the course of in vitro and in vivo work, we showed that TRIM37 promoted HCC cells migration and metastasis by inducing EMT. Furthermore, we revealed that the effect of TRIM37 mediated EMT in HCC cells was achieved by the activation of Wnt/β-catenin signaling. These finding may provide insight into the understanding of TRIM37 as a novel critical factor of HCC and a candidate target for HCC treatment. - Highlights: • Highly expression of TRIM37 is found in HCC samples compared with nontumorous samples. • TRIM37 expression is correlated with advanced HCC stages and could be an independent prognostic factor. • TRIM37 promotes cell proliferation and metastasis. • We report an E3 ligase TRIM37 affects Wnt/β-catenin signaling.

  6. Repositioning the substrate activity screening (SAS) approach as a fragment-based method for identification of weak binders.

    Science.gov (United States)

    Gladysz, Rafaela; Cleenewerck, Matthias; Joossens, Jurgen; Lambeir, Anne-Marie; Augustyns, Koen; Van der Veken, Pieter

    2014-10-13

    Fragment-based drug discovery (FBDD) has evolved into an established approach for "hit" identification. Typically, most applications of FBDD depend on specialised cost- and time-intensive biophysical techniques. The substrate activity screening (SAS) approach has been proposed as a relatively cheap and straightforward alternative for identification of fragments for enzyme inhibitors. We have investigated SAS for the discovery of inhibitors of oncology target urokinase (uPA). Although our results support the key hypotheses of SAS, we also encountered a number of unreported limitations. In response, we propose an efficient modified methodology: "MSAS" (modified substrate activity screening). MSAS circumvents the limitations of SAS and broadens its scope by providing additional fragments and more coherent SAR data. As well as presenting and validating MSAS, this study expands existing SAR knowledge for the S1 pocket of uPA and reports new reversible and irreversible uPA inhibitor scaffolds.

  7. Overexpression of human selenoprotein H in neuronal cells enhances mitochondrial biogenesis and function through activation of protein kinase A, protein kinase B, and cyclic adenosine monophosphate response element-binding protein pathway.

    Science.gov (United States)

    Mehta, Suresh L; Mendelev, Natalia; Kumari, Santosh; Andy Li, P

    2013-03-01

    Mitochondrial biogenesis is activated by nuclear encoded transcription co-activator peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α), which is regulated by several upstream factors including protein kinase A and Akt/protein kinase B. We have previously shown that selenoprotein H enhances the levels of nuclear regulators for mitochondrial biogenesis, increases mitochondrial mass and improves mitochondrial respiratory rate, under physiological condition. Furthermore, overexpression of selenoprotein H protects neuronal HT22 cells from ultraviolet B irradiation-induced cell damage by lowering reactive oxygen species production, and inhibiting activation of caspase-3 and -9, as well as p53. The objective of this study is to identify the cell signaling pathways by which selenoprotein H initiates mitochondrial biogenesis. We first confirmed our previous observation that selenoprotein H transfected HT22 cells increased the protein levels of nuclear-encoded mitochondrial biogenesis factors, peroxisome proliferator-activated receptor γ coactivator-1α, nuclear respiratory factor 1 and mitochondrial transcription factor A. We then observed that total and phosphorylation of protein kinase A, Akt/protein kinase B and cyclic adenosine monophosphate response element-binding protein (CREB) were significantly increased in selenoprotein H transfected cells compared to vector transfected HT22 cells. To verify whether the observed stimulating effects on mitochondrial biogenesis pathways are caused by selenoprotein H and mediated through CREB, we knocked down selenoprotein H mRNA level using siRNA and inhibited CREB with napthol AS-E phosphate in selenoprotein H transfected cells and repeated the measurements of the aforementioned biomarkers. Our results revealed that silencing of selenoprotein H not only decreased the protein levels of PGC-1α, nuclear respiratory factor 1 and mitochondrial transcription factor A, but also decreased the total and

  8. Chemotactic effect of urokinase-type plasminogen activator on mouse spermatozoa in vitro

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The aim of this study is to investigate the chemotactic effect of urokinase-type plasminogen activator (uPA)on mouse spermatozoa.Capillary assays were applied to study the chemotactic activity of ascending and descending gradients of uPA.Firstly,the chemotactic effect of an ascending gradient of uPA on mouse spermatozoa was observed by counting the number of spermatozoa that migrated into the capillary after incubation with uPA for 5,10,20,and 30 min,respectively,compared with that after incubation with F10.Twenty minutes was a suitable incubation time to obtain a plateau of sperm accumulation.Meanwhile,to confirm the specific effect of uPA on mouse sperm chemotaxis,uPA inhibitor (PAI-1)and anti-uPAR rabbit IgG were added to the test solution containing 20 U/mL uPA,respectively.To exclude the possibility that PAI-1 and anti-uPAR rabbit IgG may affect sperm accumulation nonspecifically,PAIl and anti-uPAR rabbit IgG were added to F10,respectively.It was found that the chemotactic effect of uPA was neutralized completely by PAI-1 and anti-uPAR rabbit IgG.PAI-1 and anti-uPAR rabbit IgG had no neutralizing effect on the sperm chemotactic effect.Lastly,the sperm chemotaxis response to a descending gradient of uPA was also observed.Taken together,the results suggest that uPA can induce sperm chemotaxis in vitro by binding to its receptor on the sperm membrane and may act as a chemoattractant in precontacting sperm-egg communication thereby increasing the chance encounter of spermatozoa and eggs.

  9. Establishment of a robust hepatitis C virus replicon cell line over-expressing P-glycoprotein that facilitates analysis of P-gp drug transporter effects on inhibitor antiviral activity.

    Science.gov (United States)

    Hernandez, Dennis; Falk, Paul; Yu, Fei; Zhai, Guangzhi; Quan, Yong; Faria, Teresa; Cao, Kai; Scola, Paul; McPhee, Fiona

    2013-01-01

    P-glycoprotein (P-gp) is an active efflux pump affecting the pharmacokinetic (PK) profiles of drugs that are P-gp substrates. The Caco-2 bi-directional assay is widely used to identify drug-P-gp interactions in vitro. For molecules exhibiting non-classical drug properties however, ambiguous results limit its use in lead optimization. The goal of this study was to develop a robust cell-based assay system to directly measure the role of P-gp-driven efflux in reducing the potency of hepatitis C virus (HCV) replication inhibitors. Vinblastine (Vin) was employed to select for a Vin-resistant HCV replicon (313-11) from the parental cell line (377-2). The 313-11 cell line was >50-fold resistant to Vin and over-expressed P-gp, as determined by Western immunoblots. Increased expression of P-gp was mediated by up-regulation of the MDR1 transcript. The reduced potency of different classes of HCV replication inhibitors in the 313-11 P-gp cell line was restored in the presence of known P-gp inhibitors. Addition of the P-gp inhibitor, tariquidar, increased the uptake of a radiolabeled HCV replication inhibitor by 14-fold in the 313-11 replicon cell line. Finally, a positive correlation was demonstrated between potency in the 313-11 replicon and the bi-directional Caco-2 efflux ratio for a panel of HCV protease inhibitors. In conclusion, a robust P-gp HCV replicon cell-based assay has been developed to measure the effect of the P-gp efflux pump on the potency of different classes of HCV replication inhibitors. This system establishes a direct correlation between antiviral activity and the effect of P-gp efflux in a single cell line.

  10. Protein kinase C alpha-CARMA3 signaling axis links Ras to NF-kappa B for lysophosphatidic acid-induced urokinase plasminogen activator expression in ovarian cancer cells.

    Science.gov (United States)

    Mahanivong, C; Chen, H M; Yee, S W; Pan, Z K; Dong, Z; Huang, S

    2008-02-21

    We reported previously that a signaling pathway consisting of G(i)-Ras-NF-kappaB mediates lysophosphatidic acid (LPA)-induced urokinase plasminogen activator (uPA) upregulation in ovarian cancer cells. However, it is not clear what signaling components link Ras to nuclear factor (NF)-kappaB for this LPA-induced event. In the present study, we found that treatment of protein kinase C (PKC) inhibitors including conventional PKC (cPKC) inhibitor Gö6976 abolished LPA-induced uPA upregulation in ovarian cancer cell lines tested, indicating the importance of cPKC activity in this LPA-induced event. Indeed, LPA stimulation led to the activation of PKCalpha and Ras-PKCalpha interaction. Although constitutively active mutants of PKCalpha (a cPKC), PKCtheta (a novel PKC (nPKC)) and PKCzeta (an atypical PKC (aPKC)) were all able to activate NF-kappaB and upregulate uPA expression, only dominant-negative PKCalpha mutant attenuated LPA-induced NF-kappaB activation and uPA upregulation. These results suggest that PKCalpha, rather than PKC isoforms in other PKC classes, participates in LPA-induced NF-kappaB activation and uPA upregulation in ovarian cancer cells. To determine the signaling components downstream of PKCalpha mediating LPA-induced uPA upregulation, we showed that forced expression of dominant-negative CARMA3 or silencing CARMA3, Bcl10 and MALT1 with specific siRNAs diminished these LPA-induced events. Furthermore, we demonstrated that PKCalpha/CARMA3 signaling axis is important in LPA-induced ovarian cancer cell in vitro invasion.

  11. NUCKS overexpression in breast cancer

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    Kittas Christos

    2009-08-01

    Full Text Available Abstract Background NUCKS (Nuclear, Casein Kinase and Cyclin-dependent Kinase Substrate is a nuclear, DNA-binding and highly phosphorylated protein. A number of reports show that NUCKS is highly expressed on the level of mRNA in several human cancers, including breast cancer. In this work, NUCKS expression on both RNA and protein levels was studied in breast tissue biopsies consisted of invasive carcinomas, intraductal proliferative lesions, benign epithelial proliferations and fibroadenomas, as well as in primary cultures derived from the above biopsies. Specifically, in order to evaluate the level of NUCKS protein in correlation with the histopathological features of breast disease, immunohistochemistry was employed on paraffin sections of breast biopsies of the above types. In addition, NUCKS expression was studied by means of Reverse Transcription PCR (RT-PCR, real-time PCR (qRT-PCR and Western immunoblot analyses in the primary cell cultures developed from the same biopsies. Results The immunohistochemical Results showed intense NUCKS staining mostly in grade I and II breast carcinomas compared to normal tissues. Furthermore, NUCKS was moderate expressed in benign epithelial proliferations, such as adenosis and sclerosing adenosis, and highly expressed in intraductal lesions, specifically in ductal carcinomas in situ (DCIS. It is worth noting that all the fibroadenoma tissues examined were negative for NUCKS staining. RT-PCR and qRT-PCR showed an increase of NUCKS expression in cells derived from primary cultures of proliferative lesions and cancerous tissues compared to the ones derived from normal breast tissues and fibroadenomas. This increase was also confirmed by Western immunoblot analysis. Although NUCKS is a cell cycle related protein, its expression does not correlate with Ki67 expression, neither in tissue sections nor in primary cell cultures. Conclusion The results show overexpression of the NUCKS protein in a number of non

  12. Reactive oxygen species regulate urokinase plasminogen activator expression and cell invasion via mitogen-activated protein kinase pathways after treatment with hepatocyte growth factor in stomach cancer cells

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    Kim Jae-Ryong

    2009-06-01

    Full Text Available Abstract Background Reactive oxygen species (ROS are closely associated with the intracellular signal cascade, thus strongly implicating involvement in tumor progression. However, the mechanism by which ROS are generated and how ROS target downstream molecules to trigger tumor metastasis is unclear. In this study, we investigated the underlying signal pathways in ROS-induced urokinase plasminogen activator (uPA expression in the human gastric cancer cells, NUGC-3 and MKN-28. Methods and Results Intracellular ROS, as determined using the fluorescent probe, 2'-7' dichlorofluorescein diacetate, decreased after treatment with hepatocyte growth factor (HGF. We confirmed that Rac-1 regulated ROS production after activation of the AKT pathway with HGF. Exogenously added H2O2 promoted the expression of HGF, but not in a dose-dependent manner and also showed negative expression of HGF after co-treatment with H2O2 and HGF. Treatment with NAC, an intracellular free radical scavenger, decreased the enhancement of uPA production and tumor invasion in both cells. We clarified the downstream pathways regulated by ROS after treatment with H2O2, which showed negative control between FRK and p38 kinase activities for uPA regulation. Conclusion HGF regulates Rac-1-induced ROS production through the Akt pathway and ROS regulates uPA production and invasion via MAP kinase, which provides novel insight into the mechanisms underlying the progression of gastric cancer.

  13. Basic Fibroblast Growth Factor-Mediated Overexpression of Vascular Endothelial Growth Factor in 1F6 Human Melanoma Cells is Regulated by Activation of PI-3K and p38 MAPK

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    Dennis Fontijn

    2009-01-01

    Full Text Available Background: 1F6 human melanoma xenografts overexpressing either the 18 kD (18kD form or all (ALL forms of human basic fibroblast growth factor (bFGF demonstrate an abundant number of microvessels and accelerated growth. We now examined whether bFGF mediates vascular endothelial growth factor (VEGF expression.

  14. A serpin-induced extensive proteolytic susceptibility of urokinase-type plasminogen activator implicates distortion of the proteinase substrate-binding pocket and oxyanion hole in the serpin inhibitory mechanism.

    Science.gov (United States)

    Egelund, R; Petersen, T E; Andreasen, P A

    2001-02-01

    The formation of stable complexes between serpins and their target serine proteinases indicates formation of an ester bond between the proteinase active-site serine and the serpin P1 residue [Egelund, R., Rodenburg, K.W., Andreasen, P.A., Rasmussen, M.S., Guldberg, R.E. & Petersen, T.E. (1998) Biochemistry 37, 6375-6379]. An important question concerning serpin inhibition is the contrast between the stability of the ester bond in the complex and the rapid hydrolysis of the acyl-enzyme intermediate in general serine proteinase-catalysed peptide bond hydrolysis. To answer this question, we used limited proteolysis to detect conformational differences between free urokinase-type plasminogen activator (uPA) and uPA in complex with plasminogen activator inhibitor-1 (PAI-1). Whereas the catalytic domain of free uPA, pro-uPA, uPA in complex with non-serpin inhibitors and anhydro-uPA in a non-covalent complex with PAI-1 was resistant to proteolysis, the catalytic domain of PAI-1-complexed uPA was susceptible to proteolysis. The cleavage sites for four different proteinases were localized in specific areas of the C-terminal beta-barrel of the catalytic domain of uPA, providing evidence that the serpin inhibitory mechanism involves a serpin-induced massive rearrangement of the proteinase active site, including the specificity pocket, the oxyanion hole, and main-chain binding area, rendering the proteinase unable to complete the normal hydrolysis of the acyl-enzyme intermediate. The distorted region includes the so-called activation domain, also known to change conformation on zymogen activation.

  15. Expression of Truncated uPA Fused to EGFP in HEK293F Cells%人尿激酶型纤溶酶原激活因子截短型突变体与绿色荧光蛋白在真核细胞HEK293F中的融合表达

    Institute of Scientific and Technical Information of China (English)

    张连成; 高丽华; 张昕; 潘芸; 高招刚; 李伊培; 胡显文; 陈惠鹏

    2013-01-01

      Objective: To construct and express eukaryotic expression vectors of the truncated urokinase-type plas⁃minogen activator(uPA) fused to enhanced green fluorescent protein(EGFP). Methods: EGFP and truncated uPA genes were amplified by PCR using plasmid pIRES2-EGFP and recombinant plasmid pcDNA3.1(+)/uPA as tem⁃plates, and inserted into eukaryotic expression vector pcDNA3.1(+) sequentially. The constructed recombinant plas⁃mids were transfected into HEK293F cells, and treated with high concentration G418. The expression of recombi⁃nant proteins was detected by confocal microscopy and ELISA. Results: DNA sequencing proved that the eukaryot⁃ic expression vectors of the fusion proteins were constructed successfully. And the green fluorescent protein could be observed in cells by confocal microscopy after the transfection, and the stable expression cell lines were got af⁃ter selected by G418. ELISA showed that the secreting type fusion proteins exist in supernatant. Conclusion: Re⁃combinant plasmids have been constructed and expressed in HEK293T cells, which will contribute to further re⁃search of the interaction of uPA and its biological function in cells.%  目的:构建人尿激酶型纤溶酶原激活因子(uPA)截短型突变体与绿色荧光蛋白(EGFP)分泌型融合表达载体并在真核细胞中表达。方法:采用PCR法,分别以质粒pIRES2-EGFP和重组质粒pcDNA3.1(+)/uPA为模板,扩增出带BamHⅠ和XbaⅠ酶切位点的EGFP及带NheⅠ和HindⅢ酶切位点的uPA截短体基因片段,先后将EGFP和截短型uPA基因片段克隆到真核表达载体pcDNA3.1(+)上,转入HEK293F细胞,用G418对转染细胞进行加压筛选,通过共聚焦显微镜观察和ELISA方法鉴定表达产物。结果:DNA测序结果显示,uPA不同截短型突变体基因片段与EGFP基因融合的真核表达载体构建成功,共聚焦显微镜观察发现HEK293F细胞中有绿色荧光且定位

  16. Fisetin inhibits migration and invasion of human cervical cancer cells by down-regulating urokinase plasminogen activator expression through suppressing the p38 MAPK-dependent NF-κB signaling pathway.

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    Ruey-Hwang Chou

    Full Text Available Fisetin (3,3',4',7-tetrahydroxyflavone, a naturally occurring flavonoid, has been reported to inhibit proliferation and induce apoptosis in several cancer types. However, its effect on the anti-metastatic potential of cervical cancer cells remains unclear. In the present study, we found that fisetin inhibits the invasion and migration of cervical cancer cells. The expression and activity of urokinase plasminogen activator (uPA was significantly suppressed by fisetin in a dose-dependent manner. We also demonstrated that fisetin reduces the phosphorylation of p38 MAPK, but not that of ERK1/2, JNK1/2, or AKT. Addition of a p38 MAPK inhibitor, SB203580, further enhanced the inhibitory effect of fisetin on the expression and activity of uPA and the invasion and motility in cervical cancer cells. Fisetin suppressed the TPA (tetradecanoylphorbol-13-acetate-induced activation of p38 MAPK and uPA, and inhibited the TPA-enhanced migratory and invasive abilities. Furthermore, the promoter activity of the uPA gene was dramatically repressed by fisetin, which disrupted the nuclear translocation of NF-κB and its binding amount on the promoter of the uPA gene, and these suppressive effects could be further enhanced by SB203580. This study provides strong evidence for the molecular mechanism of fisetin in inhibiting the aggressive phenotypes by repression of uPA via interruption of p38 MAPK-dependent NF-κB signaling pathway in cervical cancer cells and thus contributes insight to the potential of using fisetin as a therapeutic strategy against cervical cancer by inhibiting migration and invasion.

  17. Fisetin inhibits migration and invasion of human cervical cancer cells by down-regulating urokinase plasminogen activator expression through suppressing the p38 MAPK-dependent NF-κB signaling pathway.

    Science.gov (United States)

    Chou, Ruey-Hwang; Hsieh, Shu-Ching; Yu, Yung-Luen; Huang, Min-Hsien; Huang, Yi-Chang; Hsieh, Yi-Hsien

    2013-01-01

    Fisetin (3,3',4',7-tetrahydroxyflavone), a naturally occurring flavonoid, has been reported to inhibit proliferation and induce apoptosis in several cancer types. However, its effect on the anti-metastatic potential of cervical cancer cells remains unclear. In the present study, we found that fisetin inhibits the invasion and migration of cervical cancer cells. The expression and activity of urokinase plasminogen activator (uPA) was significantly suppressed by fisetin in a dose-dependent manner. We also demonstrated that fisetin reduces the phosphorylation of p38 MAPK, but not that of ERK1/2, JNK1/2, or AKT. Addition of a p38 MAPK inhibitor, SB203580, further enhanced the inhibitory effect of fisetin on the expression and activity of uPA and the invasion and motility in cervical cancer cells. Fisetin suppressed the TPA (tetradecanoylphorbol-13-acetate)-induced activation of p38 MAPK and uPA, and inhibited the TPA-enhanced migratory and invasive abilities. Furthermore, the promoter activity of the uPA gene was dramatically repressed by fisetin, which disrupted the nuclear translocation of NF-κB and its binding amount on the promoter of the uPA gene, and these suppressive effects could be further enhanced by SB203580. This study provides strong evidence for the molecular mechanism of fisetin in inhibiting the aggressive phenotypes by repression of uPA via interruption of p38 MAPK-dependent NF-κB signaling pathway in cervical cancer cells and thus contributes insight to the potential of using fisetin as a therapeutic strategy against cervical cancer by inhibiting migration and invasion.

  18. Camptothecin induces urokinase-type plasminogen activator gene-expression in human RC-K8 malignant lymphoma and H69 small cell lung cancer cells.

    OpenAIRE

    Shibakura M; Niiya K; Kiguchi T; Nakata Y; Tanimoto M

    2002-01-01

    We previously reported that anthracyclines, which could generate reactive oxygen species (ROS), could induce the urokinase-type plasminogen activator (uPA) gene expression in human RC-K8 malignant lymphoma cells and in H69 small cell lung cancer (SCLC) cells. In screening other uPA-inducible anti-cancer agents, we found that camptothecin (CPT) and its derivative, SN38, could induce uPA in RC-K8 and H69 cells. CPT and SN38, which are also used for the treatment of lymphoma and SCLC, significan...

  19. Structure, function and expression on blood and bone marrow cells of the urokinase-type plasminogen activator receptor, uPAR

    DEFF Research Database (Denmark)

    Plesner, T; Behrendt, N; Ploug, M

    1997-01-01

    Several important functions have been assigned to the receptor for urokinase-type plasminogen activator, uPAR. As implied by the name, uPAR was first identified as a high affinity cellular receptor for urokinase plasminogen activator (uPA). It mediates the binding of the zymogen, pro-uPA, to the ...

  20. Vitis vinifera VvNPR1.1 is the functional ortholog of AtNPR1 and its overexpression in grapevine triggers constitutive activation of PR genes and enhanced resistance to powdery mildew.

    Science.gov (United States)

    Le Henanff, Gaëlle; Farine, Sibylle; Kieffer-Mazet, Flore; Miclot, Anne-Sophie; Heitz, Thierry; Mestre, Pere; Bertsch, Christophe; Chong, Julie

    2011-08-01

    Studying grapevine (Vitis vinifera) innate defense mechanisms is a prerequisite to the development of new protection strategies, based on the stimulation of plant signaling pathways to trigger pathogen resistance. Two transcriptional coactivators (VvNPR1.1 and VvNPR1.2) with similarity to Arabidopsis thaliana NPR1 (Non-Expressor of PR genes 1), a well-characterized and key signaling element of the salicylic acid (SA) pathway, were recently isolated in Vitis vinifera. In this study, functional characterization of VvNPR1.1 and VvNPR1.2, including complementation of the Arabidopsis npr1 mutant, revealed that VvNPR1.1 is a functional ortholog of AtNPR1, whereas VvNPR1.2 likely has a different function. Ectopic overexpression of VvNPR1.1 in the Arabidopsis npr1-2 mutant restored plant growth at a high SA concentration, Pathogenesis Related 1 (PR1) gene expression after treatment with SA or bacterial inoculation, and resistance to virulent Pseudomonas syringae pv. maculicola bacteria. Moreover, stable overexpression of VvNPR1.1-GFP in V. vinifera resulted in constitutive nuclear localization of the fusion protein and enhanced PR gene expression in uninfected plants. Furthermore, grapevine plants overexpressing VvNPR1.1-GFP exhibited an enhanced resistance to powdery mildew infection. This work highlights the importance of the conserved SA/NPR1 signaling pathway for resistance to biotrophic pathogens in V. vinifera.

  1. Augmented expression of urokinase plasminogen activator and extracellular matrix proteins associates with multiple myeloma progression.

    Science.gov (United States)

    Khan, Rehan; Gupta, Nidhi; Kumar, Raman; Sharma, Manoj; Kumar, Lalit; Sharma, Alpana

    2014-06-01

    Multiple myeloma (MM) represents a B cell malignancy, characterized by a monoclonal proliferation of malignant plasma cells. Interactions between tumor cells and extracellular matrix (ECM) are of importance for tumor invasion and metastasis. Protein levels of urokinase plasminogen activator (uPA) and fibulin 1, nidogen and laminin in plasma and serum respectively and mRNA levels of these molecules in peripheral blood mononuclear cells were determined in 80 subjects by using ELISA and quantitative PCR and data was analyzed with severity of disease. Pearson correlation was determined to observe interrelationship between different molecules. A statistical significant increase for ECM proteins (laminin, nidogen and fibulin 1) and uPA at circulatory level as well as at mRNA level was observed compared to healthy controls. The levels of these molecules in serum might be utilized as a marker of active disease. Significant positive correlation of all ECM proteins with uPA was found and data also correlates with severity of disease. Strong association found between ECM proteins and uPA in this study supports that there might be interplay between these molecules which can be targeted. This study on these molecules may help to gain insight into processes of growth, spread, and clinical behavior of MM.

  2. Brain phenotype of transgenic mice overexpressing cystathionine β-synthase.

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    Vinciane Régnier

    Full Text Available BACKGROUND: The cystathionine β-synthase (CBS gene, located on human chromosome 21q22.3, is a good candidate for playing a role in the Down Syndrome (DS cognitive profile: it is overexpressed in the brain of individuals with DS, and it encodes a key enzyme of sulfur-containing amino acid (SAA metabolism, a pathway important for several brain physiological processes. METHODOLOGY/PRINCIPAL FINDINGS: Here, we have studied the neural consequences of CBS overexpression in a transgenic mouse line (60.4P102D1 expressing the human CBS gene under the control of its endogenous regulatory regions. These mice displayed a ∼2-fold increase in total CBS proteins in different brain areas and a ∼1.3-fold increase in CBS activity in the cerebellum and the hippocampus. No major disturbance of SAA metabolism was observed, and the transgenic mice showed normal behavior in the rotarod and passive avoidance tests. However, we found that hippocampal synaptic plasticity is facilitated in the 60.4P102D1 line. CONCLUSION/SIGNIFICANCE: We demonstrate that CBS overexpression has functional consequences on hippocampal neuronal networks. These results shed new light on the function of the CBS gene, and raise the interesting possibility that CBS overexpression might have an advantageous effect on some cognitive functions in DS.

  3. Constitutive overexpression of muscarinic receptors leads to vagal hyperreactivity.

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    Angelo Livolsi

    Full Text Available BACKGROUND: Alterations in muscarinic receptor expression and acetylcholinesterase (AchE activity have been observed in tissues from Sudden Infant Death Syndrome (SIDS. Vagal overactivity has been proposed as a possible cause of SIDS as well as of vasovagal syncopes. The aim of the present study was to seek whether muscarinic receptor overexpression may be the underlying mechanism of vagal hyperreactivity. Rabbits with marked vagal pauses following injection of phenylephrine were selected and crossed to obtain a vagal hyperreactive strain. The density of cardiac muscarinic receptors and acetylcholinesterase (AchE gene expression were assessed. Blood markers of the observed cardiac abnormalities were also sought. METHODOLOGY/PRINCIPAL FINDINGS: Cardiac muscarinic M(2 and M(3 receptors were overexpressed in hyperreactive rabbits compared to control animals (2.3-fold and 2.5-fold, respectively and the severity of the phenylephrine-induced bradycardia was correlated with their densities. A similar overexpression of M(2 receptors was observed in peripheral mononuclear white blood cells, suggesting that cardiac M(2 receptor expression can be inferred with high confidence from measurements in blood cells. Sequencing of the coding fragment of the M(2 receptor gene revealed a single nucleotide mutation in 83% of hyperreactive animals, possibly contributing for the transcript overexpression. Significant increases in AchE expression and activity were also assessed (AchE mRNA amplification ratio of 3.6 versus normal rabbits. This phenomenon might represent a compensatory consequence of muscarinic receptors overexpression. Alterations in M(2 receptor and AchE expression occurred between the 5th and the 7th week of age, a critical period also characterized by a higher mortality rate of hyperreactive rabbits (52% in H rabbits versus 13% in normal rabbits and preceeded the appearance of functional disorders. CONCLUSIONS/SIGNIFICANCE: The results suggest that

  4. Novel inhibitors of urokinase-type plasminogen activator and matrix metalloproteinase expression in metastatic cancer cell lines.

    Science.gov (United States)

    Cakarovski, Kristina; Leung, Jenny Y; Restall, Christina; Carin-Carlson, Anna; Yang, Eunice; Perlmutter, Patrick; Anderson, Robin; Medcalf, Robert; Dear, Anthony E

    2004-07-01

    The plasminogen-activating (PA) and matrix metalloproteinase (MMP) enzyme systems are implicated in proteolytic turnover of the extracellular matrix (ECM) associated with biologic processes including wound healing, inflammation and angiogenesis. Aberrant expression of components of the PA and MMP enzyme systems occurs in the pathogenesis of metastatic cancer. Oxamflatin (Ox), a novel hydroxamic acid derivative, inhibits u-PA mRNA expression and proteolytic activity while simultaneously upregulating the expression of the natural inhibitor of u-PA, plasminogen activator inhibitor type 2 (PAI-2) in metastatic cancer cells. We have characterized the effects of Ox and a novel derivative, Metacept-1 (MCT-1), on PA and MMP-mediated proteolysis and invasion in several metastatic tumor lines. Both compounds are able to inhibit u-PA-, MMP-2- and MMP-9-mediated gene expression at low micromolar concentrations as well as u-PA- and MMP-mediated proteolysis as assessed by zymography, with MCT-1 being the more effective of the 2 agents in some assays. Cellular invasion assays correlate with gene expression and zymography experiments identifying both Ox and MCT-1 as able to inhibit invasion of metastatic cancer cell lines through matrigel at nanomolar concentrations, with MCT-1 more effective than Ox in 2 of the 3 cancer cell lines assessed.

  5. Two distinct expression patterns of urokinase, urokinase receptor and plasminogen activator inhibitor-1 in colon cancer liver metastases

    DEFF Research Database (Denmark)

    Illemann, Martin; Bird, Nigel; Majeed, Ali;

    2009-01-01

    Metastatic growth and invasion by colon cancer cells in the liver requires the ability of the cancer cells to interact with the new tissue environment. Plasmin(ogen) is activated on cell surfaces by urokinase-type PA (uPA), and is regulated by uPAR and plasminogen activator inhibitor-1 (PAI-1......). To compare the expression patterns of uPA, uPAR and PAI-1 in colon cancer with that in their liver metastases, we analysed matched samples from 14 patients. In all 14 primary colon cancers, we found upregulation of uPAR, uPA mRNA and PAI-1 in primarily stromal cells at the invasive front. In 5 of the 14......, whereas 8 of the remaining 9 showed direct contact between the cancer cells and the liver parenchyma. We conclude that there are 2 distinct patterns of expression of uPAR, uPA and PAI-1 in colon cancer liver metastases and that these correlate closely with 2 morphological growth patterns. These findings...

  6. Biological effects of combined inactivation of plasminogen activator and plasminogen activator inhibitor-1 gene function in mice.

    Science.gov (United States)

    Lijnen, H R; Moons, L; Beelen, V; Carmelie, P; Collen, D

    1995-10-01

    Mice with combined homozygous deficiency of tissue-type plasminogen activator (t-PA) and urokinase-type plasminogen activator (u-PA) (T-U-), of t-PA and plasminogen activator inhibitor-1 (PAI-1) (T-P-), of u-PA and PAI-1 (U-P-) or of t-PA, u-PA, and PAI-1 (T-U-P-) were generated by inbreeding of mice with the respective deficiencies. Homologous recombination at the t-PA, u-PA and PAI-1 locus was verified by Southern blot analysis of genomic tail tip DNA, and confirmed by measurement of antigen levels in plasma or urine. T-P- and U-P- mice were apparently healthy and fertile. T-U- mice showed extensive fibrin deposition with calcification in the liver, whereas T-U-P- mice were significantly (p measured 4 h after injection of a 125I-fibrin-labeled clot prepared from plasma of wild-type (WT) mice into the jugular vein, was (mean +/- SEM of n experiments) 2 +/- 1% (n = 8) for T-P-, 49 +/- 6% (n = 9) for U-P-, 1 +/- 1% (n = 4) for T-U- and 3 +/- 3% (n = 3) for T-U-P- mice, as compared to 32 +/- 4% (n = 10) for WT, 1 +/- 0% (n = 7) for T-, 30 +/- 5% (n = 5) for U- and 58 +/- 10% (n = 6) for P- mice. Plasminogen-dependent lysis of 125I-fibrin-labeled matrix and of 3H-proline-labeled subendothelial matrix (mean +/- SEM; n = 4 to 6) was lower with thioglycollate-stimulated macrophages obtained from U-P- mice (22 +/- 7% and 5 +/- 1%, respectively), as compared to WT mice (57 +/- 14% and 18 +/- 5%, respectively) and T-P- mice (87 +/- 6% and 27 +/- 4%, respectively). A similar decrease was previously observed with U- mice, but not with T- or P- mice. Thus, the phenotype of mice with combined deficiency of t-PA and PAI-1 or of u-PA and PAI-1 is similar to the phenotype observed in mice with single deficiency of the plasminogen activator. Additional deletion of PAI-1 does not affect viability, fertility, macrophage function or thrombolytic potential of the single deficient mice. Additional deletion of PAI in mice with combined deficiency of t-PA and u-PA does not restore the

  7. Overexpression of smooth muscle myosin heavy chain leads to activation of the unfolded protein response and autophagic turnover of thick filament-associated proteins in vascular smooth muscle cells.

    Science.gov (United States)

    Kwartler, Callie S; Chen, Jiyuan; Thakur, Dhananjay; Li, Shumin; Baskin, Kedryn; Wang, Shanzhi; Wang, Zhao V; Walker, Lori; Hill, Joseph A; Epstein, Henry F; Taegtmeyer, Heinrich; Milewicz, Dianna M

    2014-05-16

    Duplications spanning nine genes at the genomic locus 16p13.1 predispose individuals to acute aortic dissections. The most likely candidate gene in this region leading to the predisposition for dissection is MYH11, which encodes smooth muscle myosin heavy chain (SM-MHC). The effects of increased expression of MYH11 on smooth muscle cell (SMC) phenotypes were explored using mouse aortic SMCs with transgenic overexpression of one isoform of SM-MHC. We found that these cells show increased expression of Myh11 and myosin filament-associated contractile genes at the message level when compared with control SMCs, but not at the protein level due to increased protein degradation. Increased expression of Myh11 resulted in endoplasmic reticulum (ER) stress in SMCs, which led to a paradoxical decrease of protein levels through increased autophagic degradation. An additional consequence of ER stress in SMCs was increased intracellular calcium ion concentration, resulting in increased contractile signaling and contraction. The increased signals for contraction further promote transcription of contractile genes, leading to a feedback loop of metabolic abnormalities in these SMCs. We suggest that overexpression of MYH11 can lead to increased ER stress and autophagy, findings that may be globally implicated in disease processes associated with genomic duplications.

  8. Overexpression of Smooth Muscle Myosin Heavy Chain Leads to Activation of the Unfolded Protein Response and Autophagic Turnover of Thick Filament-associated Proteins in Vascular Smooth Muscle Cells*

    Science.gov (United States)

    Kwartler, Callie S.; Chen, Jiyuan; Thakur, Dhananjay; Li, Shumin; Baskin, Kedryn; Wang, Shanzhi; Wang, Zhao V.; Walker, Lori; Hill, Joseph A.; Epstein, Henry F.; Taegtmeyer, Heinrich; Milewicz, Dianna M.

    2014-01-01

    Duplications spanning nine genes at the genomic locus 16p13.1 predispose individuals to acute aortic dissections. The most likely candidate gene in this region leading to the predisposition for dissection is MYH11, which encodes smooth muscle myosin heavy chain (SM-MHC). The effects of increased expression of MYH11 on smooth muscle cell (SMC) phenotypes were explored using mouse aortic SMCs with transgenic overexpression of one isoform of SM-MHC. We found that these cells show increased expression of Myh11 and myosin filament-associated contractile genes at the message level when compared with control SMCs, but not at the protein level due to increased protein degradation. Increased expression of Myh11 resulted in endoplasmic reticulum (ER) stress in SMCs, which led to a paradoxical decrease of protein levels through increased autophagic degradation. An additional consequence of ER stress in SMCs was increased intracellular calcium ion concentration, resulting in increased contractile signaling and contraction. The increased signals for contraction further promote transcription of contractile genes, leading to a feedback loop of metabolic abnormalities in these SMCs. We suggest that overexpression of MYH11 can lead to increased ER stress and autophagy, findings that may be globally implicated in disease processes associated with genomic duplications. PMID:24711452

  9. Effects of p53 overexpression on neoplastic cell pro-liferation and apoptosis in thymic carcinoma

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    To investigate p53 overexpression and its correlation with neoplastic cell proliferation and apoptosis in 20 thymic carcinomas. Methods: 20 surgical samples of thymic carcinoma were collected randomly during the past 15 years in the Guangzhou area. Immunohistochemical staining was performed using LSAB method with anti-p53 monoclonal antibody (DO-7) and proliferating cell nuclear antigen (clone PC 10) as primary antibodies. The p53 index was indicated by the number of p53 positive cells among 100 carcinoma cells. More than 25 percentage of p53 positive cells found in tissue sections was recognized as p53 overexpression. Carcinoma cell proliferation activity was assayed by PCNA index (PI), and apoptosis degree was evaluated by TUNEL (TdT-mediated dUTP-X nick end labeling) index (TI) using Boehringer Mannheim In Situ Death Detection Kit. Results: P53 positive cells could be found in vast majority of thymic carcinomas (19/20) and the overexpression rate reached 35% (7/20). The median PI (40%) of 7 cases with p53 overexpression was higher than that (31%) of 13 cases without p53 overexpression, but there was no statistical significance that existed between these two data (P>0.05). The median TI (0.5/HPF) of 7 p53 overexpression cases was much lower than that (4.5/HPF) of 13 non-overexpression cases, and there was a significant difference statistically (P<0.05). Conclusion: p53 expression was a frequent finding in thymic carcinoma cells, and the p53 overexpression which might represent p53 inactivation or gene mutation was often involved in thymic carcino-genesis. The median PCNA index of p53 overexpression group was higher than that of non-overexpression group though there existed no statistical difference. This indicates that the inhibiting function of p53 on cell proliferation seemed lost in p53 overexpressed thymic carcinomas. It is worthy to be specially mentioned that the inducing function of p53 on cell apoptosis was markedly lost in p53 overexpressed thymic

  10. Regulation of tissue-type plasminogen activator and plasminogen activator inhibitor type-1 in cultured rat Sertoli and Leydig cells

    Institute of Scientific and Technical Information of China (English)

    刘以训; 杜群; 周红明; 刘奎; 胡召元

    1996-01-01

    New data are provided to show that (i) rat Sertoli cells produce two types of plasminogen activators, tissue type (tPA) and urokinase type (uPA), and a plasminogen activator inhibitor type-1 (PAI-1); (ii) both tPA (but not uPA) and PAI-1 secretion in the culture are modified by FSH, forskolin, dbcAMP, GnRH, PMA and growth factors (EGF and FGF), but not by hCG and androstenedione (△4); (iii) in vitro secretion of tPA and PA-PAI-1 complexes of Sertoli cells are greatly enhanced by presence of Leydig cells which produce negligible tPA but measurable PAI-1 activity;(iv) combination culture of Sertoli and Leydig cells remarkably increases FSH-induced PAI-1 activity and decreases hCG- and forskolin-induced inhibitor activity as compared with that of two cell types cultured alone. These data suggest that rat Sertoli cells, similar to ovarian granulosa cells, are capable of secreting both tPA and uPA, as well as PAI-1. The interaction of Sertoli cells and Leydig cells is essential for the cells to response to

  11. Overexpression of Lamin B Receptor Results in Impaired Skin Differentiation.

    Directory of Open Access Journals (Sweden)

    Agustín Sola Carvajal

    Full Text Available Hutchinson-Gilford progeria syndrome (HGPS is a rare segmental progeroid disorder commonly caused by a point mutation in the LMNA gene that results in the increased activation of an intra-exonic splice site and the production of a truncated lamin A protein, named progerin. In our previous work, induced murine epidermal expression of this specific HGPS LMNA mutation showed impaired keratinocyte differentiation and upregulated lamin B receptor (LBR expression in suprabasal keratinocytes. Here, we have developed a novel transgenic animal model with induced overexpression of LBR in the interfollicular epidermis. LBR overexpression resulted in epidermal hypoplasia, along with the downregulation and mislocalization of keratin 10, suggesting impaired keratinocyte differentiation. Increased LBR expression in basal and suprabasal cells did not coincide with increased proliferation. Similar to our previous report of HGPS mice, analyses of γH2AX, a marker of DNA double-strand breaks, revealed an increased number of keratinocytes with multiple foci in LBR-overexpressing mice compared with wild-type mice. In addition, suprabasal LBR-positive cells showed densely condensed and peripherally localized chromatin. Our results show a moderate skin differentiation phenotype, which indicates that upregulation of LBR is not the sole contributor to the HGPS phenotype.

  12. Lysophosphatidylcholine acyltransferase 1 (LPCAT1) overexpression in human colorectal cancer.

    Science.gov (United States)

    Mansilla, Francisco; da Costa, Kerry-Ann; Wang, Shuli; Kruhøffer, Mogens; Lewin, Tal M; Orntoft, Torben F; Coleman, Rosalind A; Birkenkamp-Demtröder, Karin

    2009-01-01

    The alteration of the choline metabolite profile is a well-established characteristic of cancer cells. In colorectal cancer (CRC), phosphatidylcholine is the most prominent phospholipid. In the present study, we report that lysophosphatidylcholine acyltransferase 1 (LPCAT1; NM_024830.3), the enzyme that converts lysophosphatidylcholine into phosphatidylcholine, was highly overexpressed in colorectal adenocarcinomas when compared to normal mucosas. Our microarray transcription profiling study showed a significant (p mucosas. Immunohistochemical analysis of colon tumors with a polyclonal antibody to LPCAT1 confirmed the upregulation of the LPCAT1 protein. Overexpression of LPCAT1 in COS7 cells localized the protein to the endoplasmic reticulum and the mitochondria and increased LPCAT1 specific activity 38-fold. In cultured cells, overexpressed LPCAT1 enhanced the incorporation of [(14)C]palmitate into phosphatidylcholine. COS7 cells transfected with LPCAT1 showed no growth rate alteration, in contrast to the colon cancer cell line SW480, which significantly (p < 10(-5)) increased its growth rate by 17%. We conclude that LPCAT1 may contribute to total choline metabolite accumulation via phosphatidylcholine remodeling, thereby altering the CRC lipid profile, a characteristic of malignancy.

  13. Overexpression of Fatty-Acid-β-Oxidation-Related Genes Extends the Lifespan of Drosophila melanogaster

    Directory of Open Access Journals (Sweden)

    Shin-Hae Lee

    2012-01-01

    Full Text Available A better understanding of the aging process is necessary to ensure that the healthcare needs of an aging population are met. With the trend toward increased human life expectancies, identification of candidate genes affecting the regulation of lifespan and its relationship to environmental factors is essential. Through misexpression screening of EP mutant lines, we previously isolated several genes extending lifespan when ubiquitously overexpressed, including the two genes encoding the fatty-acid-binding protein and dodecenoyl-CoA delta-isomerase involved in fatty-acid β-oxidation, which is the main energy resource pathway in eukaryotic cells. In this study, we analyzed flies overexpressing the two main components of fatty-acid β-oxidation, and found that overexpression of fatty-acid-β-oxidation-related genes extended the Drosophila lifespan. Furthermore, we found that the ability of dietary restriction to extend lifespan was reduced by the overexpression of fatty-acid-β-oxidation-related genes. Moreover, the overexpression of fatty-acid-β-oxidation-related genes enhanced stress tolerance to oxidative and starvation stresses and activated the dFOXO signal, indicating translocation to the nucleus and transcriptional activation of the dFOXO target genes. Overall, the results of this study suggest that overexpression of fatty-acid-β-oxidation-related genes extends lifespan in a dietary-restriction-related manner, and that the mechanism of this process may be related to FOXO activation.

  14. Zastosowanie fizykoterapii w leczeniu dolegliwości bólowych odcinka lędźwiowego kręgosłupa = The use of physical therapy in the treatment of pain lumbar spine

    OpenAIRE

    2015-01-01

    Plaskiewicz Anna, Kałużny Krystian, Kochański Bartosz, Płoszaj Ola, Lulińska-Kuklik Ewelina, Weber-Rajek Magdalena, Zukow Walery. Zastosowanie fizykoterapii w leczeniu dolegliwości bólowych odcinka lędźwiowego kręgosłupa = The use of physical therapy in the treatment of pain lumbar spine. Journal of Education, Health and Sport. 2015;5(5):11-20. ISSN 2391-8306. DOI: 10.5281/zenodo.17290 http://ojs.ukw.edu.pl/index.php/johs/article/view/2015%3B5%285%29%3A11-20   htt...

  15. Retraction: "Down-regulation of uPA and uPAR by 3,3'-diindolylmethane contributes to the inhibition of cell growth and migration of breast cancer cells" by Ahmad et al.

    Science.gov (United States)

    2016-08-01

    The above article, published online on August 19, 2009 in Wiley Online Library (wileyonlinelibrary.com), has been retracted by agreement between the journal Editor in Chief, Gary S. Stein, and Wiley Periodicals, Inc. The retraction has been agreed following an investigation from Wayne State University involving the third author and the corresponding author that found Figure 5C to be inappropriately re-used and re-labeled. REFERENCE Ahmad A, Kong D, Wang Z, Sarkar SH, Banerjee S, Sarkar FH. 2009. Down-regulation of uPA and uPAR by 3,3'-diindolylmethane contributes to the inhibition of cell growth and migration of breast cancer cells. J Cell Biochem 108:916-925; doi: 10.1002/jcb.22323.

  16. Significance of Aurora B overexpression in hepatocellular carcinoma. Aurora B Overexpression in HCC

    Directory of Open Access Journals (Sweden)

    Lin Zhong-Zhe

    2010-08-01

    Full Text Available Abstract Background To investigate the significance of Aurora B expression in hepatocellular carcinoma (HCC. Methods The Aurora B and Aurora A mRNA level was measured in 160 HCCs and the paired nontumorous liver tissues by reverse transcription-polymerase chain reaction. Mutations of the p53 and β-catenin genes were analyzed in 134 and 150 tumors, respectively, by direct sequencing of exon 2 to exon 11 of p53 and exon 3 of β-catenin. Anticancer effects of AZD1152-HQPA, an Aurora B kinase selective inhibitor, were examined in Huh-7 and Hep3B cell lines. Results Aurora B was overexpressed in 98 (61% of 160 HCCs and in all 7 HCC cell lines examined. The overexpression of Aurora B was associated with Aurora A overexpression (P = 0.0003 and p53 mutation (P = 0.002 and was inversely associated with β-catenin mutation (P = 0.002. Aurora B overexpression correlated with worse clinicopathologic characteristics. Multivariate analysis confirmed that Aurora B overexpression was an independent poor prognostic factor, despite its interaction with Aurora A overexpression and mutations of p53 and β-catenin. In Huh-7 and Hep3B cells, AZD1152-HQPA induced proliferation blockade, histone H3 (Ser10 dephosphorylation, cell cycle disturbance, and apoptosis. Conclusion Aurora B overexpression is an independent molecular marker predicting tumor invasiveness and poor prognosis of HCC. Aurora B kinase selective inhibitors are potential therapeutic agents for HCC treatment.

  17. Six1 overexpression at early stages of HPV16-mediated transformation of human keratinocytes promotes differentiation resistance and EMT

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Hanwen [Department of Drug Discovery and Biomedical Sciences, South Carolina College of Pharmacy, University of South Carolina, Columbia, SC 29208 (United States); Pirisi, Lucia [Department of Pathology, Microbiology and Immunology, University of South Carolina School of Medicine, University of South Carolina, Columbia, SC 29208 (United States); Creek, Kim E., E-mail: creekk@sccp.sc.edu [Department of Drug Discovery and Biomedical Sciences, South Carolina College of Pharmacy, University of South Carolina, Columbia, SC 29208 (United States)

    2015-01-01

    Previous studies in our laboratory discovered that SIX1 mRNA expression increased during in vitro progression of HPV16-immortalized human keratinocytes (HKc/HPV16) toward a differentiation-resistant (HKc/DR) phenotype. In this study, we explored the role of Six1 at early stages of HPV16-mediated transformation by overexpressing Six1 in HKc/HPV16. We found that Six1 overexpression in HKc/HPV16 increased cell proliferation and promoted cell migration and invasion by inducing epithelial–mesenchymal transition (EMT). Moreover, the overexpression of Six1 in HKc/HPV16 resulted in resistance to serum and calcium-induced differentiation, which is the hallmark of the HKc/DR phenotype. Activation of MAPK in HKc/HPV16 overexpressing Six1 is linked to resistance to calcium-induced differentiation. In conclusion, this study determined that Six1 overexpression resulted in differentiation resistance and promoted EMT at early stages of HPV16-mediated transformation of human keratinocytes. - Highlights: • Six1 expression increases during HPV16-mediated transformation. • Six1 overexpression causes differentiation resistance in HPV16-immortalized cells. • Six1 overexpression in HPV16-immortalized keratinocytes activates MAPK. • Activation of MAPK promotes EMT and differentiation resistance. • Six1 overexpression reduces Smad-dependent TGF-β signaling.

  18. Mechanisms of cell cycle control revealed by a systematic and quantitative overexpression screen in S. cerevisiae.

    Directory of Open Access Journals (Sweden)

    Wei Niu

    2008-07-01

    Full Text Available Regulation of cell cycle progression is fundamental to cell health and reproduction, and failures in this process are associated with many human diseases. Much of our knowledge of cell cycle regulators derives from loss-of-function studies. To reveal new cell cycle regulatory genes that are difficult to identify in loss-of-function studies, we performed a near-genome-wide flow cytometry assay of yeast gene overexpression-induced cell cycle delay phenotypes. We identified 108 genes whose overexpression significantly delayed the progression of the yeast cell cycle at a specific stage. Many of the genes are newly implicated in cell cycle progression, for example SKO1, RFA1, and YPR015C. The overexpression of RFA1 or YPR015C delayed the cell cycle at G2/M phases by disrupting spindle attachment to chromosomes and activating the DNA damage checkpoint, respectively. In contrast, overexpression of the transcription factor SKO1 arrests cells at G1 phase by activating the pheromone response pathway, revealing new cross-talk between osmotic sensing and mating. More generally, 92%-94% of the genes exhibit distinct phenotypes when overexpressed as compared to their corresponding deletion mutants, supporting the notion that many genes may gain functions upon overexpression. This work thus implicates new genes in cell cycle progression, complements previous screens, and lays the foundation for future experiments to define more precisely roles for these genes in cell cycle progression.

  19. Urokinase-type Plasminogen Activator-like Proteases in Teleosts Lack Genuine Receptor-binding Epidermal Growth Factor-like Domains

    DEFF Research Database (Denmark)

    Bager, René; Kristensen, Thomas Kielsgaard; Jensen, Jan Kristian

    2012-01-01

    Plasminogen activation catalyzed by urokinase-type plasminogen activator (uPA) plays an important role in normal and pathological tissue remodeling processes. Since its discovery in the mid-1980s, the cell membrane-anchored urokinase-type plasminogen activator receptor (uPAR) has been believed...... mammals and uPA-catalyzed plasminogen activation in fish may occur mainly in solution. Studies with nonmammalian vertebrate species are needed to obtain a comprehensive understanding of the mechanism of plasminogen activation....

  20. EFFECTS OF p53 OVEREXPRESSION ON NEOPLASTIC CELL MITOSIS AND APOPTOSIS IN NASOPHARYNGEAL CARCINOMA

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    To investigate the p53 overexpression and its correlation withneoplastic cell mitosis and apoptosis in 43 nasopharyngeal carcinomas (NPCs). Methods: Forty-three pretreated NPC biopsy samples were randomly collected in the year 1997 for this study. p53 overexpression was detected by LSAB immunohistochemistry using DO-7 primary antibody. Mitotic figures were counted on H&E stained slides, and apoptotic cells on TUNEL-stained slides by use of in-situ cell death detection kit. Both of mitotic and apoptotic cells were quantitated by cell numbers per one high power field (5′ 40) averagely in terms of mitotic index (MI) and TUNEL index (TI), respectively. To compare the mean MIs of two groups categorized by different percentages of positive p53 positive cells found in NPC specimens was taken for the purpose of designating the criterion of p53 overexpression. And then, the correlation of p53 overexpression with MI and TI was made by statistical analysis. Results: Because statistically significant difference appeared at the criterion of 20%, the p53 overexpression of NPC was defined as≥20% of positive cells found. The p53 overexpression thus could be detected in 37 out of 43 NPCs, reaching 86.05% (37/43). The mean MI (1.87± 1.78/HPF) of 37 NPCs with p53 overexpression was significantly higher than that (0.76± 0.63/HPF) of 6 NPCs without p53 overexpression, the P value being <0.05. However, there was no statistical difference between the mean TI (24.50± 26.66HPF) of 37 NPCs with p53 overexpression and TI (23.17± 25.30/HPF) of 6 NPCs without p53 overexpression. Conclusions: p53 overexpression of NPC could be designated by ≥20% of positive neoplastic cells found in pretreated NPC specimens, and the rate of which reached 86.05% (37/43). The overexpressed p53 could enhance cell proliferative activity in pretreated NPCs represented by increasing of MI, but showed no effect on neoplastic cell apoptosis.

  1. Cardiac specific ATP-sensitive K+ channel (KATP) overexpression results in embryonic lethality.

    Science.gov (United States)

    Toib, Amir; Zhang, Hai Xia; Broekelmann, Thomas J; Hyrc, Krzysztof L; Guo, Qiusha; Chen, Feng; Remedi, Maria S; Nichols, Colin G

    2012-09-01

    Transgenic mice overexpressing SUR1 and gain of function Kir6.2[∆N30, K185Q] K(ATP) channel subunits, under cardiac α-myosin heavy chain (αMHC) promoter control, demonstrate arrhythmia susceptibility and premature death. Pregnant mice, crossed to carry double transgenic progeny, which harbor high levels of both overexpressed subunits, exhibit the most extreme phenotype and do not deliver any double transgenic pups. To explore the fetal lethality and embryonic phenotype that result from K(ATP) overexpression, wild type (WT) and K(ATP) overexpressing embryonic cardiomyocytes were isolated, cultured and voltage-clamped using whole cell and excised patch clamp techniques. Whole mount embryonic imaging, Hematoxylin and Eosin (H&E) and α smooth muscle actin (αSMA) immunostaining were used to assess anatomy, histology and cardiac development in K(ATP) overexpressing and WT embryos. Double transgenic embryos developed in utero heart failure and 100% embryonic lethality by 11.5 days post conception (dpc). K(ATP) currents were detectable in both WT and K(ATP)-overexpressing embryonic cardiomyocytes, starting at early stages of cardiac development (9.5 dpc). In contrast to adult cardiomyocytes, WT and K(ATP)-overexpressing embryonic cardiomyocytes exhibit basal and spontaneous K(ATP) current, implying that these channels may be open and active under physiological conditions. At 9.5 dpc, live double transgenic embryos demonstrated normal looping pattern, although all cardiac structures were collapsed, probably representing failed, non-contractile chambers. In conclusion, K(ATP) channels are present and active in embryonic myocytes, and overexpression causes in utero heart failure and results in embryonic lethality. These results suggest that the K(ATP) channel may have an important physiological role during early cardiac development.

  2. Identification of developmental regulatory genes in Aspergillus nidulans by overexpression.

    Science.gov (United States)

    Marhoul, J F; Adams, T H

    1995-02-01

    Overexpression of several Aspergillus nidulans developmental regulatory genes has been shown to cause growth inhibition and development at inappropriate times. We set out to identify previously unknown developmental regulators by constructing a nutritionally inducible A. nidulans expression library containing small, random genomic DNA fragments inserted next to the alcA promoter [alcA(p)] in an A. nidulans transformation vector. Among 20,000 transformants containing random alcA(p) genomic DNA fusion constructs, we identified 66 distinct mutant strains in which alcA(p) induction resulted in growth inhibition as well as causing other detectable phenotypic changes. These growth inhibited mutants were divided into 52 FIG (Forced expression Inhibition of Growth) and 14 FAB (Forced expression Activation of brlA) mutants based on whether or not alcA(p) induction resulted in accumulation of mRNA for the developmental regulatory gene brlA. In four FAB mutants, alcA(p) induction not only activated brlA expression but also caused hyphae to differentiate into reduced conidiophores that produced viable spores from the tips as is observed after alcA(p)::brlA induction. Sequence analyses of the DNA fragments under alcA(p) control in three of these four sporulating strains showed that in two cases developmental activation resulted from overexpression of previously uncharacterized genes, whereas in the third strain, the alcA(p) was fused to brlA. The potential uses for this strategy in identifying genes whose overexpression results in specific phenotypic changes like developmental induction are discussed.

  3. Overexpression of protein O-fucosyltransferase 1 accelerates hepatocellular carcinoma progression via the Notch signaling pathway.

    Science.gov (United States)

    Ma, Lijie; Dong, Pingping; Liu, Longzi; Gao, Qiang; Duan, Meng; Zhang, Si; Chen, She; Xue, Ruyi; Wang, Xiaoying

    2016-04-29

    Aberrant activation of Notch signaling frequently occurs in liver cancer, and is associated with liver malignancies. However, the mechanisms regulating pathologic Notch activation in hepatocellular carcinoma (HCC) remain unclear. Protein O-fucosyltransferase 1 (Pofut1) catalyzes the addition of O-linked fucose to the epidermal growth factor-like repeats of Notch. In the present study, we detected the expression of Pofut1 in 8 HCC cell lines and 253 human HCC tissues. We reported that Pofut1 was overexpressed in HCC cell lines and clinical HCC tissues, and Pofut1 overexpression clinically correlated with the unfavorable survival and high disease recurrence in HCC. The in vitro assay demonstrated that Pofut1 overexpression accelerated the cell proliferation and migration in HCC cells. Furthermore, Pofut1 overexpression promoted the binding of Notch ligand Dll1 to Notch receptor, and hence activated Notch signaling pathway in HCC cells, indicating that Pofut1 overexpression could be a reason for the aberrant activation of Notch signaling in HCC. Taken together, our findings indicated that an aberrant activated Pofut1-Notch pathway was involved in HCC progression, and blockage of this pathway could be a promising strategy for the therapy of HCC.

  4. Bicyclic Peptide Inhibitor of Urokinase-Type Plasminogen Activator

    DEFF Research Database (Denmark)

    Roodbeen, Renée; Paaske, Berit; Jiang, Longguang;

    2013-01-01

    The development of protease inhibitors for pharmacological intervention has taken a new turn with the use of peptidebased inhibitors. Here, we report the rational design of bicyclic peptide inhibitors of the serine protease urokinase-type plasminogen activator (uPA), based on the established...... monocyclic peptide, upain-2. It was successfully converted to a bicyclic peptide, without loss of inhibitory properties. The aim was to produce a peptide cyclised by an amide bond with an additional stabilising across-the-ring covalent bond. We expected this bicyclic peptide to exhibit a lower entropic...... burden upon binding. Two bicyclic peptides were synthesised with affinities similar to that of upain-2, and their binding energetics were evaluated by isothermal titration calorimetry. Indeed, compared to upain-2, the bicyclic peptides showed reduced loss of entropy upon binding to uPA. We also...

  5. Overexpression of c-myc induces epithelial mesenchymal transition in mammary epithelial cells.

    Science.gov (United States)

    Cho, Kyoung Bin; Cho, Min Kyong; Lee, Won Young; Kang, Keon Wook

    2010-07-28

    The c-myc gene is frequently overexpressed in human breast cancer and its target genes are involved in tumorigenesis. Epithelial mesenchymal transitions (EMT), where cells undergo a developmental switch from a polarized epithelial phenotype to a highly motile mesenchymal phenotype, are associated with invasion and motility of cancer cells. Basal E-cadherin expression was down-regulated in c-myc overexpressing MCF10A (c-myc-MCF10A) cells compared to GFP-overexpressing MCF10A (GFP-MCF10A) cells, while N-cadherin was distinctly increased in c-myc-MCF10A cells. Given that glycogen synthase kinase-3beta (GSK-3beta) and the snail axis have key roles in E-cadherin deregulation during EMT, we investigated the role of GSK-3beta/snail signaling pathways in the induction of EMT by c-myc overexpression. In contrast to GFP-MCF10A cells, both the transcriptional activity and the ubiquitination-dependent protein stability of snail were enhanced in c-myc-MCF10A cells, and this was reversed by GSK-3beta overexpression. We also found that c-myc overexpression inhibits GSK-3beta activity through activation of extracellular signal-regulated kinase (ERK). Inhibition of ERK by dominant negative mutant transfection or chemical inhibitor significantly suppressed snail gene transcription. These results suggest that c-myc overexpression during transformation of mammary epithelial cells (MEC) is involved in EMTs via ERK-dependent GSK-3beta inactivation and subsequent snail activation.

  6. Conditional overexpression of connective tissue growth factor disrupts postnatal lung development.

    Science.gov (United States)

    Wu, Shu; Platteau, Astrid; Chen, Shaoyi; McNamara, George; Whitsett, Jeffrey; Bancalari, Eduardo

    2010-05-01

    Connective tissue growth factor (CTGF) is a member of an emerging family of immediate-early gene products that coordinates complex biological processes during development, differentiation, and tissue repair. Overexpression of CTGF is associated with mechanical ventilation with high tidal volume and oxygen exposure in newborn lungs. However, the role of CTGF in postnatal lung development and remodeling is not well understood. In the present study, a double-transgenic mouse model was generated with doxycycline-inducible overexpression of CTGF in respiratory epithelial cells. Overexpression of CTGF from Postnatal Days 1-14 resulted in thicker alveolar septa and decreased secondary septal formation. This is correlated with increased myofibroblast differentiation and disorganized elastic fiber deposition in alveolar septa. Overexpression of CTGF also decreased alveolar capillary network formation. There were increased alpha-smooth muscle actin expression and collagen deposition, and dramatic thickening in the peribronchial/peribronchiolar and perivascular regions in the double-transgenic lungs. Furthermore, overexpression of CTGF increased integrin-linked kinase expression, activated its downstream signaling target, Akt, as well as increased mRNA expression of fibronectin. These data demonstrate that overexpression of CTGF disrupts alveologenesis and capillary formation, and induces fibrosis during the critical period of alveolar development. These histologic changes are similar to those observed in lungs of infants with bronchopulmonary dysplasia.

  7. Enhancement of geraniol resistance of Escherichia coli by MarA overexpression.

    Science.gov (United States)

    Shah, Asad Ali; Wang, Chonglong; Chung, Young-Ryun; Kim, Jae-Yean; Choi, Eui-Sung; Kim, Seon-Won

    2013-03-01

    Improvement of a microorganism's tolerance against organic solvents is required for a microbial factory producing terpenoid based biofuels. The bacterial genes, marA, imp, cls and cti have been found to increase organic solvent tolerance. Thus, the tolerance against the following terpenoids (isopentenol, geraniol, myrcene, and farnesol) was studied with overexpression of marA, imp, cls and cti genes in Escherichia coli. The marA overexpression significantly enhanced the tolerance of E. coli against geraniol, whereas there was no tolerance improvement against the terpenoids by overexpression of cls and cti genes. The imp overexpression even yielded sensitive phenotype to the tested solvents. The colony forming efficiency of the marA overexpressing E. coli was increased by 10(4)-fold in plate overlay of geraniol compared to that of wild type E. coli and a two-fold decrease of intracellular geraniol accumulation was also observed in liquid culture of geraniol. Single knock-out mutations of marA, or one of the following genes (acrA, acrB and tolC) encoding AcrAB-TolC efflux pump made E. coli hypersensitive to geraniol. The geraniol tolerance conferred by marA overexpression was attributed to the AcrAB-TolC efflux pump that is activated by MarA.

  8. Cyclopamine and jervine induce COX-2 overexpression in human erythroleukemia cells but only cyclopamine has a pro-apoptotic effect

    Energy Technology Data Exchange (ETDEWEB)

    Ghezali, Lamia; Leger, David Yannick; Limami, Youness [Université de Limoges, FR 3503 GEIST, EA 1069 “Laboratoire de Chimie des Substances Naturelles”, GDR CNRS 3049, Faculté de Pharmacie, Laboratoire de Biochimie et Biologie Moléculaire, 2 rue du Docteur Marcland, 87025 Limoges Cedex (France); Cook-Moreau, Jeanne [Université de Limoges, FR 3503 GEIST, UMR CNRS 7276 “Contrôle de la réponse immune B et lymphoproliférations”, Faculté de Médecine, 2 rue du Docteur Marcland, 87025 Limoges Cedex (France); Beneytout, Jean-Louis [Université de Limoges, FR 3503 GEIST, EA 1069 “Laboratoire de Chimie des Substances Naturelles”, GDR CNRS 3049, Faculté de Pharmacie, Laboratoire de Biochimie et Biologie Moléculaire, 2 rue du Docteur Marcland, 87025 Limoges Cedex (France); Liagre, Bertrand, E-mail: bertrand.liagre@unilim.fr [Université de Limoges, FR 3503 GEIST, EA 1069 “Laboratoire de Chimie des Substances Naturelles”, GDR CNRS 3049, Faculté de Pharmacie, Laboratoire de Biochimie et Biologie Moléculaire, 2 rue du Docteur Marcland, 87025 Limoges Cedex (France)

    2013-04-15

    Erythroleukemia is generally associated with a very poor response and survival to current available therapeutic agents. Cyclooxygenase-2 (COX-2) has been described to play a crucial role in the proliferation and differentiation of leukemia cells, this enzyme seems to play an important role in chemoresistance in different cancer types. Previously, we demonstrated that diosgenin, a plant steroid, induced apoptosis in HEL cells with concomitant COX-2 overexpression. In this study, we investigated the antiproliferative and apoptotic effects of cyclopamine and jervine, two steroidal alkaloids with similar structures, on HEL and TF1a human erythroleukemia cell lines and, for the first time, their effect on COX-2 expression. Cyclopamine, but not jervine, inhibited cell proliferation and induced apoptosis in these cells. Both compounds induced COX-2 overexpression which was responsible for apoptosis resistance. In jervine-treated cells, COX-2 overexpression was NF-κB dependent. Inhibition of NF-κB reduced COX-2 overexpression and induced apoptosis. In addition, cyclopamine induced apoptosis and COX-2 overexpression via PKC activation. Inhibition of the PKC pathway reduced both apoptosis and COX-2 overexpression in both cell lines. Furthermore, we demonstrated that the p38/COX-2 pathway was involved in resistance to cyclopamine-induced apoptosis since p38 inhibition reduced COX-2 overexpression and increased apoptosis in both cell lines. - Highlights: ► Cyclopamine alone but not jervine induces apoptosis in human erythroleukemia cells. ► Cyclopamine and jervine induce COX-2 overexpression. ► COX-2 overexpression is implicated in resistance to cyclopamine-induced apoptosis. ► Apoptotic potential of jervine is restrained by NF-κB pathway activation. ► PKC is involved in cyclopamine-induced apoptosis and COX-2 overexpression.

  9. Proteome analysis of a Lactococcus lactis strain overexpressing gapA suggests that the gene product is an auxiliary glyceraldehyde 3-phosphate dehydrogenase

    DEFF Research Database (Denmark)

    Willemoes, Martin; Kilstrup, Mogens; Roepstorff, P.;

    2002-01-01

    strain that overexpessed the gapA gene derived from MG1363 upon nisin induction. Compared to the wild-type, the overexpressing strain had a 3.4-fold elevated level of specific GAPDH activity when grown in the presence of nisin. In both MG 1363 and the gapA overexpressing strain the GAPDH activity...

  10. Ectopic overexpression of the cell wall invertase gene CIN1 leads to dehydration avoidance in tomato

    DEFF Research Database (Denmark)

    Albacete, Alfonso; Cantero-Navarro, Elena; Grosskinsky, Dominik Kilian

    2015-01-01

    in plant growth and development. However, the physiological role of invertases during adaptation to abiotic stress conditions is not yet fully understood. Here it is shown that plant adaptation to drought stress can be markedly improved in tomato (Solanum lycopersicum L.) by overexpression of the cell wall...... invertase (cwInv) gene CIN1 from Chenopodium rubrum. CIN1 overexpression limited stomatal conductance under normal watering regimes, leading to reduced water consumption during the drought period, while photosynthetic activity was maintained. This caused a strong increase in water use efficiency (up to 50......%), markedly improving water stress adaptation through an efficient physiological strategy of dehydration avoidance. Drought stress strongly reduced cwInv activity and induced its proteinaceous inhibitor in the leaves of the wild-type plants. However, the CIN1-overexpressing plants registered 3- to 6-fold...

  11. Antitumor efficacy of piperine in the treatment of human HER2-overexpressing breast cancer cells.

    Science.gov (United States)

    Do, Minh Truong; Kim, Hyung Gyun; Choi, Jae Ho; Khanal, Tilak; Park, Bong Hwan; Tran, Thu Phuong; Jeong, Tae Cheon; Jeong, Hye Gwang

    2013-12-01

    Piperine is a bioactive component of black pepper, Piper nigrum Linn, commonly used for daily consumption and in traditional medicine. Here, the molecular mechanisms by which piperine exerts antitumor effects in HER2-overexpressing breast cancer cells was investigated. The results showed that piperine strongly inhibited proliferation and induced apoptosis through caspase-3 activation and PARP cleavage. Furthermore, piperine inhibited HER2 gene expression at the transcriptional level. Blockade of ERK1/2 signaling by piperine significantly reduced SREBP-1 and FAS expression. Piperine strongly suppressed EGF-induced MMP-9 expression through inhibition of AP-1 and NF-κB activation by interfering with ERK1/2, p38 MAPK, and Akt signaling pathways resulting in a reduction in migration. Finally, piperine pretreatment enhanced sensitization to paclitaxel killing in HER2-overexpressing breast cancer cells. Our findings suggest that piperine may be a potential agent for the prevention and treatment of human breast cancer with HER2 overexpression.

  12. 自然流产患者绒毛组织PAI-14G/5G多态性和uPA基因的表达及其意义%Expression and Clinical Significance of PAI-1 4G/5G Polymorphism and uPA in the Villus of Spontaneous Abortion

    Institute of Scientific and Technical Information of China (English)

    杨玲竹; 瞿小玲; 李亚敏

    2011-01-01

    目的:探讨纤溶酶原激活物抑制剂-1(PAI-1)4G/5G多态性和纤溶酶原激活剂(uPA)与自然流产的关系及其在妊娠中的作用.方法:正常早孕(对照组)人工流产和自然流产(实验组)稽留流产的绒毛组织各30例,应用免疫组织化学PV法检测绒毛组织中PAI-1和uPA蛋白表达情况,等位基因特异性-PCR(AS-PCR)法检测PAI-14G/5G多态性的表达情况,RT-PCR法检测uPA mRNA表达情况.结果:① PAI-1蛋白主要在绒毛组织的滋养细胞质中表达,其表达对照组低于实验组(P<0.05).uPA与PAI-1蛋白在细胞中分布一致,其表达水平对照组高于实验组(P<0.05).②PAI-14G/4G基因型和4G等位基因表达水平对照组低于实验组(P<0.05),uPA mRNA表达水平对照组高于实验组(P<0.05).③PAI-1和uPA蛋白在自然流产患者绒毛组织中的表达呈负相关(r=-0.639).结论:PAI-14G/5G多态性和uPA异常表达可能与自然流产的发生有关.%Objective: To explore the correlation of PAI-14G/5G polymorphism and uPA with spontaneous abortion and their effect during pregnancy. Methods: Each of 30 samples was from the villus of normal pregnancy (control group) and spontaneous abortion (experimental group), respectively. Immunchistochchemistry analysis was used to detect the protein expression of PAI-1 and uPA. AS-PCR analysis was used to detect PAI-1 4G/5G polymorphism expression and RT-PCR analysis was used to detect uPA mRNA expression. Results: 1) The expression of PAI-1 protein in spontaneous abortion villus was higher than that of normal pregnancy (P< 0.05)and it was mainly expressed in the trophocyte cytoplasm. The expression of uPA protein in spontaneous abortion villus was lower than that of normal pregnancy (P<0.05) and it's distribution was consistent with the PAI-1.2)The frequencies of 4G/4G genotype and 4G alleles of PAI- 1 were signicantly higher in abortions compared with the control. The expression of uPA mRNA was significantly lower in abortions

  13. Matrix metalloproteinase-9 and urokinase plasminogen activator mediate interleukin-1-induced neurotoxicity.

    Science.gov (United States)

    Thornton, Peter; Pinteaux, Emmanuel; Allan, Stuart M; Rothwell, Nancy J

    2008-01-01

    Matrix metalloproteinases (MMPs) are endopeptidases known to mediate acute neuronal injury, but it is unclear whether these proteases are induced by the primary insult or by inflammation associated with injury. We have reported recently that interleukin-1 (IL-1) induces neurotoxicity by an astrocyte-dependent mechanism. The aim of the present study was to test the hypothesis that MMPs mediate IL-1 neurotoxicity in rat, glial-neuronal cocultures. IL-1beta induced the release of astrocytic MMP-9 in cocultures, whilst an antagonist of MMP-9 inhibited IL-1beta-induced neuronal death. Urokinase plasminogen activator (uPA) was constitutively expressed on neuronal membrane fractions, and amiloride (an antagonist of uPA) or plasminogen activator inhibitor (PAI)-1 significantly reduced IL-1beta-induced neurotoxicity. Thus, neuronal uPA contributes to IL-1 neurotoxicity, and may be responsible for activating MMP-9 released from IL-1-primed astrocytes. In summary, IL-1-induced neurotoxicity is dependent on extracellular protease activity, and these mechanisms may contribute to neuronal cell death in CNS diseases.

  14. The relationship between oral squamous cell carcinoma of MMP-1, MMP-2, UPA's expression of tumor invasion and metastasis%口腔鳞癌中MMP-1、MMP-2、uPA的表达与肿瘤侵袭和转移的关系

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

      目的探讨基质金属蛋白酶-1、2(MMP-1、MMP-2)及尿激酶型纤溶酶原激活物(uPA)的表达与口腔鳞癌侵袭和转移的关系。方法选取我院收治的60例口腔鳞癌患者,用免疫组化检测癌旁正常组织和癌组织中MMP-1、MM P-2、uPA的含量并进行比较。结果口腔鳞癌患者肿瘤组织与口腔癌旁正常组织MMP-1、MMP-2、uPA的含量有统计学差异(P <0.05)。结论口腔鳞癌中MMP-1、MMP-2、uPA的表达与肿瘤的侵袭、转移有着密切的关系,有可能成为评价肿瘤侵袭、转移程度的指标。%Objective To investigate the relationship between MMP-1, MMP-2, UPA's expression in oral squamous cell carcinoma invasion and metastasis, to provide experimental evidence for tumor treatment and prognosis. Methods 60 patients with oral squamous cell carcinoma patients in our hospitalwere for the study, immunohistochemical detection of adjacent normal tissue and cancer tissue in MMP-1, the MM P -2, UPA's content. Results Patients with oral squamous cell carcinoma tumor cavity adjacent normal tissue MMP-1, MMP-2, the UPA's content difference were significant(P <0.05). Conclusion Oral squamous cell carcinoma of MMP-1, MMP-2, UPA's expression in tumor invasion and metastasis are closely related, it is possible to become the evaluation of invasion, metastasis indicators.

  15. SERCA overexpression reduces hydroxyl radical injury in murine myocardium.

    Science.gov (United States)

    Hiranandani, Nitisha; Bupha-Intr, Tepmanas; Janssen, Paul M L

    2006-12-01

    Hydroxyl radicals (*OH) are involved in the pathogenesis of ischemia-reperfusion injury and are observed in clinical situations, including acute heart failure, stroke, and myocardial infarction. Acute transient exposure to *OH causes an intracellular Ca(2+) overload and leads to impaired contractility. We investigated whether upregulation of sarcoplasmic reticulum Ca(2+)-ATPase function (SERCA) can attenuate *OH-induced dysfunction. Small, contracting right ventricular papillary muscles from wild-type (WT) SERCA1a-overexpressing (transgenic, TG) and SERCA2a heterogeneous knockout (HET) mice were directly exposed to *OH. This brief 2-min exposure led to a transient elevation of diastolic force (F(dia)) and depression of developed force (F(dev)). In WT mice, F(dia) increased to 485 +/- 49% and F(dev) decreased to 11 +/- 3%. In sharp contrast, in TG mice F(dia) increased only to 241 +/- 17%, whereas F(dev) decreased only to 51 +/- 5% (P group. The results indicate that SERCA overexpression can reduce the *OH-induced contractile dysfunction in murine myocardium, whereas a reduced SR Ca(2+)-ATPase activity aggravates this injury. Loss of pPLB levels at Ser16 likely amplifies the differences observed in injury response.

  16. Effects of CYP7A1 overexpression on cholesterol and bile acid homeostasis.

    Science.gov (United States)

    Pandak, W M; Schwarz, C; Hylemon, P B; Mallonee, D; Valerie, K; Heuman, D M; Fisher, R A; Redford, K; Vlahcevic, Z R

    2001-10-01

    The initial and rate-limiting step in the classic pathway of bile acid biosynthesis is 7alpha-hydroxylation of cholesterol, a reaction catalyzed by cholesterol 7alpha-hydroxylase (CYP7A1). The effect of CYP7A1 overexpression on cholesterol homeostasis in human liver cells has not been examined. The specific aim of this study was to determine the effects of overexpression of CYP7A1 on key regulatory steps involved in hepatocellular cholesterol homeostasis, using primary human hepatocytes (PHH) and HepG2 cells. Overexpression of CYP7A1 in HepG2 cells and PHH was accomplished by using a recombinant adenovirus encoding a CYP7A1 cDNA (AdCMV-CYP7A1). CYP7A1 overexpression resulted in a marked activation of the classic pathway of bile acid biosynthesis in both PHH and HepG2 cells. In response, there was decreased HMG-CoA-reductase (HMGR) activity, decreased acyl CoA:cholesterol acyltransferase (ACAT) activity, increased cholesteryl ester hydrolase (CEH) activity, and increased low-density lipoprotein receptor (LDLR) mRNA expression. Changes observed in HMGR, ACAT, and CEH mRNA levels paralleled changes in enzyme specific activities. More specifically, LDLR expression, ACAT activity, and CEH activity appeared responsive to an increase in cholesterol degradation after increased CYP7A1 expression. Conversely, accumulation of the oxysterol 7alpha-hydroxycholesterol in the microsomes after CYP7A1 overexpression was correlated with a decrease in HMGR activity.

  17. Overexpression of HDAC1 induces cellular senescence by Sp1/PP2A/pRb pathway

    Energy Technology Data Exchange (ETDEWEB)

    Chuang, Jian-Ying [Department of Pharmacology, National Cheng-Kung University, Tainan 701, Taiwan (China); Hung, Jan-Jong, E-mail: petehung@mail.ncku.edu.tw [Department of Pharmacology, National Cheng-Kung University, Tainan 701, Taiwan (China); Institute of Bioinformatics and Biosignal Transduction, National Cheng-Kung University, Tainan 701, Taiwan (China)

    2011-04-15

    Highlights: {yields} Overexpression of HDAC1 induces Sp1 deacetylation and raises Sp1/p300 complex formation to bind to PP2Ac promoter. {yields} Overexpression of HDAC1 strongly inhibits the phosphorylation of pRb through up-regulation of PP2A. {yields} Overexpressed HDAC1 restrains cell proliferaction and induces cell senescence though a novel Sp1/PP2A/pRb pathway. -- Abstract: Senescence is associated with decreased activities of DNA replication, protein synthesis, and cellular division, which can result in deterioration of cellular functions. Herein, we report that the growth and division of tumor cells were significantly repressed by overexpression of histone deacetylase (HDAC) 1 with the Tet-off induced system or transient transfection. In addition, HDAC1 overexpression led to senescence through both an accumulation of hypophosphorylated active retinoblastoma protein (pRb) and an increase in the protein level of protein phosphatase 2A catalytic subunit (PP2Ac). HDAC1 overexpression also increased the level of Sp1 deacetylation and elevated the interaction between Sp1 and p300, and subsequently that Sp1/p300 complex bound to the promoter of PP2Ac, thus leading to induction of PP2Ac expression. Similar results were obtained in the HDAC1-Tet-off stable clone. Taken together, these results indicate that HDAC1 overexpression restrained cell proliferation and induced premature senescence in cervical cancer cells through a novel Sp1/PP2A/pRb pathway.

  18. Overexpressed TP73 induces apoptosis in medulloblastoma

    Directory of Open Access Journals (Sweden)

    Perlaky Laszlo

    2007-07-01

    Full Text Available Abstract Background Medulloblastoma is the most common malignant brain tumor of childhood. Children who relapse usually die of their disease, which reflects resistance to radiation and/or chemotherapy. Improvements in outcome require a better understanding of the molecular basis of medulloblastoma growth and treatment response. TP73 is a member of the TP53 tumor suppressor gene family that has been found to be overexpressed in a variety of tumors and mediates apoptotic responses to genotoxic stress. In this study, we assessed expression of TP73 RNA species in patient tumor specimens and in medulloblastoma cell lines, and manipulated expression of full-length TAp73 and amino-terminal truncated ΔNp73 to assess their effects on growth. Methods We analyzed medulloblastoma samples from thirty-four pediatric patients and the established medulloblastoma cell lines, Daoy and D283MED, for expression of TP73 RNA including the full-length transcript and the 5'-terminal variants that encode the ΔNp73 isoform, as well as TP53 RNA using quantitative real time-RTPCR. Protein expression of TAp73 and ΔNp73 was quantitated with immunoblotting methods. Clinical outcome was analyzed based on TP73 RNA and p53 protein expression. To determine effects of overexpression or knock-down of TAp73 and ΔNp73 on cell cycle and apoptosis, we analyzed transiently transfected medulloblastoma cell lines with flow cytometric and TUNEL methods. Results Patient medulloblastoma samples and cell lines expressed full-length and 5'-terminal variant TP73 RNA species in 100-fold excess compared to non-neoplastic brain controls. Western immunoblot analysis confirmed their elevated levels of TAp73 and amino-terminal truncated ΔNp73 proteins. Kaplan-Meier analysis revealed trends toward favorable overall and progression-free survival of patients whose tumors display TAp73 RNA overexpression. Overexpression of TAp73 or ΔNp73 induced apoptosis under basal growth conditions in vitro and

  19. Nucleophosmin is overexpressed in thyroid tumors

    Energy Technology Data Exchange (ETDEWEB)

    Pianta, Annalisa; Puppin, Cinzia [Dipartimento di Scienze e Tecnologie Biomediche, Universita di Udine, Udine (Italy); Franzoni, Alessandra; Fabbro, Dora [Azienda Ospedaliero-Universitaria ' S. Maria della Misericordia' Udine, Udine (Italy); Di Loreto, Carla [Dipartimento di Ricerche Mediche e Morfologiche, Universita di Udine, Udine (Italy); Bulotta, Stefania [Department of Pharmacobiological Sciences, Universita di Catanzaro ' Magna Graecia' , Catanzaro (Italy); Deganuto, Marta; Paron, Igor; Tell, Gianluca [Dipartimento di Scienze e Tecnologie Biomediche, Universita di Udine, Udine (Italy); Puxeddu, Efisio [Department of Internal Medicine, Universita di Perugia, Perugia (Italy); Filetti, Sebastiano [Department of Clinical Sciences, Universita di Roma ' La Sapienza' , Roma (Italy); Russo, Diego [Department of Pharmacobiological Sciences, Universita di Catanzaro ' Magna Graecia' , Catanzaro (Italy); Damante, Giuseppe, E-mail: giuseppe.damante@uniud.it [Dipartimento di Scienze e Tecnologie Biomediche, Universita di Udine, Udine (Italy); Azienda Ospedaliero-Universitaria ' S. Maria della Misericordia' Udine, Udine (Italy)

    2010-07-02

    Nucleophosmin (NPM) is a protein that contributes to several cell functions. Depending on the context, it can act as an oncogene or tumor suppressor. No data are available on NPM expression in thyroid cells. In this work, we analyzed both NPM mRNA and protein levels in a series of human thyroid tumor tissues and cell lines. By using immunohistochemistry, NPM overexpression was detected in papillary, follicular, undifferentiated thyroid cancer, and also in follicular benign adenomas, indicating it as an early event during thyroid tumorigenesis. In contrast, various levels of NPM mRNA levels as detected by quantitative RT-PCR were observed in tumor tissues, suggesting a dissociation between protein and transcript expression. The same behavior was observed in the normal thyroid FRTL5 cell lines. In these cells, a positive correlation between NPM protein levels, but not mRNA, and proliferation state was detected. By using thyroid tumor cell lines, we demonstrated that such a post-mRNA regulation may depend on NPM binding to p-Akt, whose levels were found to be increased in the tumor cells, in parallel with reduction of PTEN. In conclusion, our present data demonstrate for the first time that nucleophosmin is overexpressed in thyroid tumors, as an early event of thyroid tumorigenesis. It seems as a result of a dysregulation occurring at protein and not transcriptional level related to an increase of p-Akt levels of transformed thyrocytes.

  20. Quantitation of the receptor for urokinase plasminogen activator by enzyme-linked immunosorbent assay

    DEFF Research Database (Denmark)

    Rønne, E; Behrendt, N; Ploug, M;

    1994-01-01

    variant of uPAR, suPAR, has been constructed by recombinant technique and the protein content of a purified suPAR standard preparation was determined by amino acid composition analysis. The sensitivity of the assay (0.6 ng uPAR/ml) is strong enough to measure uPAR in extracts of cultured cells and cancer......Binding of the urokinase plasminogen activator (uPA) to a specific cell surface receptor (uPAR) plays a crucial role in proteolysis during tissue remodelling and cancer invasion. An immunosorbent assay for the quantitation of uPAR has now been developed. This assay is based on two monoclonal...... tissue. Recent studies have shown that a high uPA level in tumor extracts is in some cancers associated with poor prognosis. The present assay will now allow similar prognostic studies of uPAR levels....

  1. Improved antibody production in Chinese hamster ovary cells by ATF4 overexpression

    OpenAIRE

    Haredy, AM; Nishizawa, A.; Honda, K.; T. Ohya; Ohtake, H; Omasa, T

    2013-01-01

    To improve antibody production in Chinese hamster ovary (CHO) cells, the humanized antibody-producing CHO DP-12-SF cell line was transfected with the gene encoding activating transcription factor 4 (ATF4), a central factor in the unfolded protein response. Overexpression of ATF4 significantly enhanced the production of antibody in the CHO DP-12-SF cell line. The specific IgG production rate of in the ATF4-overexpressing CHO-ATF4-16 cells was approximately 2.4 times that of the parental host c...

  2. Absence of Hyperplasia in Gasp-1 Overexpressing Mice is Dependent on Myostatin Up-Regulation

    Directory of Open Access Journals (Sweden)

    Caroline Brun

    2014-09-01

    Full Text Available Background/Aims: Overexpression of Gasp-1, an inhibitor of myostatin, leads to a hypermuscular phenotype due to hypertrophy rather than hyperplasia in mice. However to date, the cellular and molecular mechanisms underlying this phenotype are not investigated. Methods: Skeletal muscles of overexpressing Gasp-1 mice, called Tg(Gasp-1 mice, were analyzed by histological methods. Satellite cell-derived myoblasts from these mice were used to investigate the molecular mechanisms. Results: We demonstrated that hypertrophy in Tg(Gasp-1 mice was related to a myonuclear accretion during the first 3 postnatal weeks and an activation of the pro-hypertrophic Akt/mTORC/p70S6K signaling. In accordance with these results, we showed that overexpressing Gasp-1 primary myoblasts proliferated faster and myonuclei average per myotube was increased during differentiation. Molecular analysis revealed that Gasp-1 overexpression resulted in increased myostatin expression related to its auto-regulation. Despite its inhibition, myostatin led to Pax7 deregulation through its non-canonical Erk1/2 signaling pathway. Consistent with this, inhibition of Erk1/2 signaling pathway as well as neutralization of secreted myostatin rescue the Pax7 expression in overexpressing Gasp-1 myoblasts. Conclusion: Our study shows that myostatin is able to act independently of its canonical pathway to regulate the Pax7 expression. Altogether, our results indicate that myostatin could regulate muscle development despite its protein inhibition.

  3. Cetuximab enhanced the efficacy of chemotherapeutic agent in ABCB1/P-glycoprotein-overexpressing cancer cells.

    Science.gov (United States)

    Wang, Fang; Chen, Yifan; Huang, Lihua; Liu, Tao; Huang, Yue; Zhao, Jianming; Wang, Xiaokun; Yang, Ke; Ma, Shaolin; Huang, Liyan; To, Kenneth Kin Wah; Gu, Yong; Fu, Liwu

    2015-12-01

    The overexpression of ATP-binding cassette (ABC) transporters is closely associated with the development of multidrug resistance (MDR) in certain types of cancer, which represents a formidable obstacle to the successful cancer chemotherapy. Here, we investigated that cetuximab, an EGFR monoclonal antibody, reversed the chemoresistance mediated by ABCB1, ABCG2 or ABCC1. Our results showed that cetuximab significantly enhanced the cytotoxicity of ABCB1 substrate agent in ABCB1-overexpressing MDR cells but had no effect in their parental drug sensitive cells and ABCC1, ABCG2 overexpressing cells. Furthermore, cetuximab markedly increased intracellular accumulation of doxorubicin (DOX) and rhodamine 123 (Rho 123) in ABCB1-overexpressing MDR cancer cells in a concentration-dependent manner. Cetuximab stimulated the ATPase activity but did not alter the expression level of ABCB1 or block phosphorylation of AKT and ERK. Interestingly, cetuximab decreased the cell membrane fluidity which was known to decrease the function of ABCB1. Our findings advocate further clinical investigation of combination chemotherapy of cetuximab and conventional chemotherapeutic drugs in ABCB1 overexpressing cancer patients.

  4. Overexpressed Genes/ESTs and Characterization of Distinct Amplicons on 17823 in Breast Cancer Cells

    Directory of Open Access Journals (Sweden)

    Ayse E. Erson

    2001-01-01

    Full Text Available 17823 is a frequent site of gene amplification in breast cancer. Several lines of evidence suggest the presence of multiple amplicons on 17823. To characterize distinct amplicons on 17823 and localize putative oncogenes, we screened genes and expressed sequence tags (ESTs in existing physical and radiation hybrid maps for amplification and overexpression in breast cancer cell lines by semiquantitative duplex PCR, semiquantitative duplex RT-PCR, Southern blot, Northern blot analyses. We identified two distinct amplicons on 17823, one including TBX2 and another proximal region including RPS6KB1 (PS6K and MUL. In addition to these previously reported overexpressed genes, we also identified amplification and overexpression of additional uncharacterized genes and ESTs, some of which suggest potential oncogenic activity. In conclusion, we have further defined two distinct regions of gene amplification and overexpression on 17823 with identification of new potential oncogene candidates. Based on the amplification and overexpression patterns of known and as of yet unrecognized genes on 17823, it is likely that some of these genes mapping to the discrete amplicons function as oncogenes and contribute to tumor progression in breast cancer cells.

  5. Mitogen activated protein kinase kinase kinase 3 (MAP3K3/MEKK3) overexpression is an early event in esophageal tumorigenesis and is a predictor of poor disease prognosis

    OpenAIRE

    2014-01-01

    Background Mitogen-activated protein kinase kinase kinase3 (MAP3K3/MEKK3) was identified to be differentially expressed in esophageal squamous cell carcinoma (ESCC) using cDNA microarrays by our laboratory. Here in we determined the clinical significance of MEKK3 in ESCC. Methods Immunohistochemical analysis of MEKK3 expression was carried out in archived tissue sections from 93 ESCCs, 47 histologically normal and 61 dysplastic esophageal tissues and correlated with clinicopathological parame...

  6. ß-Cell Specific Overexpression of GPR39 Protects against Streptozotocin-Induced Hyperglycemia

    DEFF Research Database (Denmark)

    Egerod, Kristoffer Lihme; Jin, Chunyu; Petersen, Pia Steen;

    2011-01-01

    and OGTT. Although the overexpression of the constitutively active GPR39 receptor in animals not treated with streptozotocin appeared by itself to impair the glucose tolerance slightly and to decrease the ß-cell mass, it nevertheless totally protected against the gradual hyperglycemia in the steptozotocin...

  7. Overexpression of citrus polygalacturonase-inhibiting protein in citrus black rot pathogen Alternaria citri.

    Science.gov (United States)

    Katoh, Hiroshi; Nalumpang, Sarunya; Yamamoto, Hiroyuki; Akimitsu, Kazuya

    2007-05-01

    The rough lemon (Citrus jambhiri) gene encoding polygalacturonase-inhibiting protein (RlemPGIPA) was overexpressed in the pathogenic fungus Alternaria citri. The overexpression mutant AcOPI6 retained the ability to utilize pectin as a sole carbon source, and the overexpression of polygalacturonase-inhibiting protein did not have any effect on the growth of AcOPI6 in potato dextrose and pectin medium. The pathogenicity of AcOPI6 to cause a black rot symptom in citrus fruits was also unchanged. Polygalacturonase-inhibiting protein was secreted together with endopolygalacturonase into culture filtrates of AcOPI6, and oligogalacturonides were digested from polygalacturonic acid by both proteins in the culture filtrates. The reaction mixture containing oligogalacturonides possessed activity for induction of defense-related gene, RlemLOX, in rough lemon leaves.

  8. Enhanced acetaminophen hepatotoxicity in transgenic mice overexpressing BCL-2.

    Science.gov (United States)

    Adams, M L; Pierce, R H; Vail, M E; White, C C; Tonge, R P; Kavanagh, T J; Fausto, N; Nelson, S D; Bruschi, S A

    2001-11-01

    Mitochondria play an important role in the cell death induced by many drugs, including hepatotoxicity from overdose of the popular analgesic, acetaminophen (APAP). To investigate mitochondrial alterations associated with APAP-induced hepatotoxicity, the subcellular distribution of proapoptotic BAX was determined. Based on the antiapoptotic characteristics of BCL-2, we further hypothesized that if a BAX component was evident then BCL-2 overexpression may be hepatoprotective. Mice, either with a human bcl-2 transgene (-/+) or wild-type mice (WT; -/-), were dosed with 500 or 600 mg/kg (i.p.) APAP or a nonhepatotoxic isomer, N-acetyl-m-aminophenol (AMAP). Immunoblot analyses indicated increased mitochondrial BAX-beta content very early after APAP or AMAP treatment. This was paralleled by disappearance of BAX-alpha from the cytosol of APAP treated animals and, to a lesser extent, with AMAP treatment. Early pathological evidence of APAP-induced zone 3 necrosis was seen in bcl-2 (-/+) mice, which progressed to massive panlobular necrosis with hemorrhage by 24 h. In contrast, WT mice dosed with APAP showed a more typical, and less severe, centrilobular necrosis. AMAP-treated bcl-2 (-/+) mice displayed only early microvesicular steatosis without progression to extensive necrosis. Decreased complex III activity, evident as early as 6 h after treatment, correlated well with plasma enzyme activities at 24 h (AST r(2) = 0.89, ALT r(2) = 0.87) thereby confirming a role for mitochondria in APAP-mediated hepatotoxicity. In conclusion, these data suggest for the first time that BAX may be an early determinant of APAP-mediated hepatotoxicity and that BCL-2 overexpression unexpectedly enhances APAP hepatotoxicity.

  9. Fascin overexpression promotes neoplastic progression in oral squamous cell carcinoma

    Directory of Open Access Journals (Sweden)

    Alam Hunain

    2012-01-01

    Full Text Available Abstract Background Fascin is a globular actin cross-linking protein, which plays a major role in forming parallel actin bundles in cell protrusions and is found to be associated with tumor cell invasion and metastasis in various type of cancers including oral squamous cell carcinoma (OSCC. Previously, we have demonstrated that fascin regulates actin polymerization and thereby promotes cell motility in K8-depleted OSCC cells. In the present study we have investigated the role of fascin in tumor progression of OSCC. Methods To understand the role of fascin in OSCC development and/or progression, fascin was overexpressed along with vector control in OSCC derived cells AW13516. The phenotype was studied using wound healing, Boyden chamber, cell adhesion, Hanging drop, soft agar and tumorigenicity assays. Further, fascin expression was examined in human OSCC samples (N = 131 using immunohistochemistry and level of its expression was correlated with clinico-pathological parameters of the patients. Results Fascin overexpression in OSCC derived cells led to significant increase in cell migration, cell invasion and MMP-2 activity. In addition these cells demonstrated increased levels of phosphorylated AKT, ERK1/2 and JNK1/2. Our in vitro results were consistent with correlative studies of fascin expression with the clinico-pathological parameters of the OSCC patients. Fascin expression in OSCC showed statistically significant correlation with increased tumor stage (P = 0.041, increased lymph node metastasis (P = 0.001, less differentiation (P = 0.005, increased recurrence (P = 0.038 and shorter survival (P = 0.004 of the patients. Conclusion In conclusion, our results indicate that fascin promotes tumor progression and activates AKT and MAPK pathways in OSCC-derived cells. Further, our correlative studies of fascin expression in OSCC with clinico-pathological parameters of the patients indicate that fascin may prove to be useful in prognostication and

  10. Enhanced fatty acid flux triggered by adiponectin overexpression.

    Science.gov (United States)

    Shetty, Shoba; Ramos-Roman, Maria A; Cho, You-Ree; Brown, Jonathan; Plutzky, Jorge; Muise, Eric S; Horton, Jay D; Scherer, Philipp E; Parks, Elizabeth J

    2012-01-01

    Adiponectin overexpression in mice increases insulin sensitivity independent of adiposity. Here, we combined stable isotope infusion and in vivo measurements of lipid flux with transcriptomic analysis to characterize fatty acid metabolism in transgenic mice that overexpress adiponectin via the aP2-promoter (ADNTg). Compared with controls, fasted ADNTg mice demonstrated a 31% reduction in plasma free fatty acid concentrations (P = 0.008), a doubling of ketones (P = 0.028), and a 68% increase in free fatty acid turnover in plasma (15.1 ± 1.5 vs. 25.3 ± 6.8 mg/kg · min, P = 0.011). ADNTg mice had 2-fold more brown adipose tissue mass, and triglyceride synthesis and turnover were 5-fold greater in this organ (P = 0.046). Epididymal white adipose tissue was slightly reduced, possibly due to the approximately 1.5-fold increase in the expression of genes involved in oxidation (peroxisome proliferator-activated receptor α, peroxisome proliferator-activated receptor-γ coactivator 1α, and uncoupling protein 3). In ADNTg liver, lipogenic gene expression was reduced, but there was an unexpected increase in the expression of retinoid pathway genes (hepatic retinol binding protein 1 and retinoic acid receptor beta and adipose Cyp26A1) and liver retinyl ester content (64% higher, P < 0.02). Combined, these data support a physiological link between adiponectin signaling and increased efficiency of triglyceride synthesis and hydrolysis, a process that can be controlled by retinoids. Interactions between adiponectin and retinoids may underlie adiponectin's effects on intermediary metabolism.

  11. VEGF receptor-2 (Flk-1 overexpression in mice counteracts focal epileptic seizures.

    Directory of Open Access Journals (Sweden)

    Litsa Nikitidou

    Full Text Available Vascular endothelial growth factor (VEGF was first described as an angiogenic agent, but has recently also been shown to exert various neurotrophic and neuroprotective effects in the nervous system. These effects of VEGF are mainly mediated by its receptor, VEGFR-2, which is also referred to as the fetal liver kinase receptor 1 (Flk-1. VEGF is up-regulated in neurons and glial cells after epileptic seizures and counteracts seizure-induced neurodegeneration. In vitro, VEGF administration suppresses ictal and interictal epileptiform activity caused by AP4 and 0 Mg(2+ via Flk-1 receptor. We therefore explored whether increased VEGF signaling through Flk-1 overexpression may regulate epileptogenesis and ictogenesis in vivo. To this extent, we used transgenic mice overexpressing Flk-1 postnatally in neurons. Intriguingly, Flk-1 overexpressing mice were characterized by an elevated threshold for seizure induction and a decreased duration of focal afterdischarges, indicating anti-ictal action. On the other hand, the kindling progression in these mice was similar to wild-type controls. No significant effects on blood vessels or glia cells, as assessed by Glut1 and GFAP immunohistochemistry, were detected. These results suggest that increased VEGF signaling via overexpression of Flk-1 receptors may directly affect seizure activity even without altering angiogenesis. Thus, Flk-1 could be considered as a novel target for developing future gene therapy strategies against ictal epileptic activity.

  12. NDRG1 overexpression promotes the progression of esophageal squamous cell carcinoma through modulating Wnt signaling pathway

    Science.gov (United States)

    Ai, Runna; Sun, Yulin; Guo, Zhimin; Wei, Wei; Zhou, Lanping; Liu, Fang; Hendricks, Denver T.; Xu, Yang; Zhao, Xiaohang

    2016-01-01

    ABSTRACT N-myc down-regulated gene 1 (NDRG1) has been shown to regulate tumor growth and metastasis in various malignant tumors and also to be dysregulated in esophageal squamous cell carcinoma (ESCC). Here, we show that NDRG1 overexpression (91.9%, 79/86) in ESCC tumor tissues is associated with poor overall survival of esophageal cancer patients. When placed in stable transfectants of the KYSE 30 ESCC cell line generated by lentiviral transduction with the ectopic overexpression of NDRG1, the expression of transducin-like enhancer of Split 2 (TLE2) was decreased sharply, however β−catenin was increased. Mechanistically, NDRG1 physically associates with TLE2 and β−catenin to affect the Wnt pathway. RNA interference and TLE2 overexpression studies demonstrate that NDRG1 fails to active Wnt pathway compared with isogenic wild-type controls. Strikingly, NDRG1 overexpression induces the epithelial mesenchymal transition (EMT) through activating the Wnt signaling pathway in ESCC cells, decreased the expression of E-cadherin and enhanced the expression of Snail. Our study elucidates a mechanism of NDRG1-regulated Wnt pathway activation and EMT via affecting TLE2 and  β-catenin expression in esophageal cancer cells. This indicates a pro-oncogenic role for NDRG1 in esophageal cancer cells whereby it modulates tumor progression. PMID:27414086

  13. Targeted anticancer therapy: overexpressed receptors and nanotechnology.

    Science.gov (United States)

    Akhtar, Mohd Javed; Ahamed, Maqusood; Alhadlaq, Hisham A; Alrokayan, Salman A; Kumar, Sudhir

    2014-09-25

    Targeted delivery of anticancer drugs to cancer cells and tissues is a promising field due to its potential to spare unaffected cells and tissues, but it has been a major challenge to achieve success in these therapeutic approaches. Several innovative approaches to targeted drug delivery have been devised based on available knowledge in cancer biology and on technological advancements. To achieve the desired selectivity of drug delivery, nanotechnology has enabled researchers to design nanoparticles (NPs) to incorporate anticancer drugs and act as nanocarriers. Recently, many receptor molecules known to be overexpressed in cancer have been explored as docking sites for the targeting of anticancer drugs. In principle, anticancer drugs can be concentrated specifically in cancer cells and tissues by conjugating drug-containing nanocarriers with ligands against these receptors. Several mechanisms can be employed to induce triggered drug release in response to either endogenous trigger or exogenous trigger so that the anticancer drug is only released upon reaching and preferentially accumulating in the tumor tissue. This review focuses on overexpressed receptors exploited in targeting drugs to cancerous tissues and the tumor microenvironment. We briefly evaluate the structure and function of these receptor molecules, emphasizing the elegant mechanisms by which certain characteristics of cancer can be exploited in cancer treatment. After this discussion of receptors, we review their respective ligands and then the anticancer drugs delivered by nanotechnology in preclinical models of cancer. Ligand-functionalized nanocarriers have delivered significantly higher amounts of anticancer drugs in many in vitro and in vivo models of cancer compared to cancer models lacking such receptors or drug carrying nanocarriers devoid of ligand. This increased concentration of anticancer drug in the tumor site enabled by nanotechnology could have a major impact on the efficiency of cancer

  14. Overexpression of Colligin 2 in Glioma Vasculature is Associated with Overexpression of Heat Shock Factor 2.

    Science.gov (United States)

    Mustafa, Dana A M; Sieuwerts, Anieta M; Zheng, Ping Pin; Kros, Johan M

    2010-10-20

    In previous studies we found expression of the protein colligin 2 (heat shock protein 47 (HSP47), SERPINH1) in glioma neovasculature while not in normal brain tissue. Generally, the regulation of heat shock gene expression in eukaryotes is mediated by heat shock factors (HSF). In mammals, three heat shock transcription factors, HSF-1, -2, and -4, have been isolated. Here we investigated the relation between the expression of colligin 2 and these heat shock factors at the mRNA level using real-time reverse transcriptase PCR (qRT-PCR) in different grades of astrocytic tumorigenesis, viz., low-grade glioma and glioblastoma. Endometrium samples, representing physiological angiogenesis, were included as controls. Since colligin 2 is a chaperon for collagens, the gene expression of collagen I (COL1A1) was also investigated. The blood vessel density of the samples was monitored by expression of the endothelial marker CD31 (PECAM1). Because NG2-immunopositive pericytic cells are involved in glioma neovascularization, the expression of NG2 (CSPG4) was also measured.We demonstrate overexpression of HSF2 in both stages of glial tumorigenesis (reaching significance only in low-grade glioma) and also minor elevated levels of HSF1 as compared to normal brain. There were no differences in expression of HSF4 between low-grade glioma and normal brain while HSF4 was downregulated in glioblastoma. In the endometrium samples, none of the HSFs were upregulated. In the low-grade gliomas SERPINH appeared to be slightly overexpressed with a parallel 4-fold upregulation of COL1A1, while in glioblastoma there was over 5-fold overexpression of SERPINH1 and more than 150-fold overexpression of COL1A1. In both the lowgrade gliomas and the glioblastomas overexpression of CSPG4 was found and overexpression of PECAM1 was only found in the latter. Our data suggest that the upregulated expression of colligin 2 in glioma is accompanied by upregulation of COL1A1, CSPG4, HSF2 and to a lesser extent

  15. Over-expression of LPTS-L in hepatocellular carcinoma cell line SMMC-7721 induces crisis

    Institute of Scientific and Technical Information of China (English)

    Cheng Liao; Mu-Jun Zhao; Jing Zhao; Di Jia; Hai Song; Zai-Ping Li

    2002-01-01

    AIM: To evaluate the function of the longer transcripts LPTS-Lin hepatocellular carcinoma cell line SMMC-7721.METHODS: SMMC-7721 cells were transfected with LPTSL expression construct and stably transfected cells were selected by G418. Multiple single clones formed and were checked for their phenotype. In the study of the effect on telomerase activity of LPTS-Lin vitro, GST-LPTS-L fusion protein was expressed in E.coli and purified by glutathioneagarose column. Telomeric repeat amplification protocol (TRAP) assays were performed to study the influence of telomerase activity in SMMC-7721 cells.RESULTS: Over-expression of LPTS-L induced SMMC-7721 cells into crisis. LPTS-L could inhibit the telomerase activity in SMMC-7721 cellsin vitro.CONCLUSION: LPTS-L is a potent telomeraseinhibitor. Over-expression of LPTS-L can induce hepatoma cells into crisis due to the reduction of telomerase activity.

  16. SERCA1 overexpression minimizes skeletal muscle damage in dystrophic mouse models.

    Science.gov (United States)

    Mázala, Davi A G; Pratt, Stephen J P; Chen, Dapeng; Molkentin, Jeffery D; Lovering, Richard M; Chin, Eva R

    2015-05-01

    Duchenne muscular dystrophy (DMD) is characterized by progressive muscle wasting secondary to repeated muscle damage and inadequate repair. Elevations in intracellular free Ca²⁺ have been implicated in disease progression, and sarcoplasmic/endoplasmic reticulum Ca²⁺-ATPase 1 (SERCA1) overexpression has been shown to ameliorate the dystrophic phenotype in mdx mice. The purpose of this study was to assess the effects of SERCA1 overexpression in the more severe mdx/Utr(-/-) mouse model of DMD. Mice overexpressing SERCA1 were crossed with mdx/Utr ± mice to generate mdx/Utr(-/-)/+SERCA1 mice and compared with wild-type (WT), WT/+SERCA1, mdx/+SERCA1, and genotype controls. Mice were assessed at ∼12 wk of age for changes in Ca²⁺ handling, muscle mass, quadriceps torque, markers of muscle damage, and response to repeated eccentric contractions. SERCA1-overexpressing mice had a two- to threefold increase in maximal sarcoplasmic reticulum Ca²⁺-ATPase activity compared with WT which was associated with normalization in body mass for both mdx/+SERCA1 and mdx/Utr(-/-)/+SERCA1. Torque deficit in the quadriceps after eccentric injury was 2.7-fold greater in mdx/Utr(-/-) vs. WT mice, but only 1.5-fold greater in mdx/Utr(-/-)/+SERCA1 vs. WT mice, an attenuation of 44%. Markers of muscle damage (% centrally nucleated fibers, necrotic area, and serum creatine kinase levels) were higher in both mdx and mdx/Utr(-/-) vs. WT, and all were attenuated by overexpression of SERCA1. These data indicate that SERCA1 overexpression ameliorates functional impairments and cellular markers of damage in a more severe mouse model of DMD. These findings support targeting intracellular Ca²⁺ control as a therapeutic approach for DMD.

  17. The Effect of cdk- 5 Overexpression and Overactivation on Tau Hyperphosphorylation in Cultured N2a Cells

    Institute of Scientific and Technical Information of China (English)

    CHEN Juan; LI Hong-lian; FENG You-mei; WANG Jian-zhi

    2005-01-01

    Neurofibrillary tangles (NFTs) are one of the neuropathological hallmarks of Alzheimer' s disease (AD) and abnormally hyperphosphorylated tau is the major protein of NFTs. It was reported that cyclin-dependent kinase5 (Cdk-5) could phosphorylate tau at most AD-related epitopes in vivo. In this study, we investigated the effect of cdk-5 overexpression on tau hyperphosphorylation in neuroblastoma N2a cells. We demonstrated that overexpression of cdk-5 which resulted in a 3.5-fold Cdk5 activation in the transfected cells induced a dramatic increase in phosphorylation of tau at several phosphorylation sites. Overexpression of cdk-5 led to a reduced staining with antibody Tau-1 and an enhanced staining with antibody PHF-1, suggesting hy perphosphorylation of tau at Ser199/202 and Ser396/404 sites. It implies that in vitro overexpression of cdk-5 leads to Cdk5 overactivation and tau hyperphosphorylation may be the underline mechanism.

  18. 重组融合蛋白C-CPE-ETA′对卵巢癌细胞的细胞毒作用%Target-specific cytotoxic activity of recombinant fusion toxin C-CPE-ETA′ against CLDN-3, 4-overexpressing ovarian cancer cells

    Institute of Scientific and Technical Information of China (English)

    姚勤; 郑庆梅; 温君凤; 吕腾; 魏明谦; 戴淑真

    2010-01-01

    Objective The aim of this study was to explore the possibility of creating a toxin,C-CPE-ETA′, by fusing C-terminal high affinity binding domain of CPE(C-CPE)with a truncated form of Pseudomonas aeruginosa exotoxin A(ETA')and to examine whether C-CPE-ETA' could specifically target CLDN-3,4 molecule and the targeted toxin was cytotoxic against CLDN-3,4-overexpressing ovarian cancer.Methods CLDN-3 and CLDN-4 expressions were analyzed at the mRNA level in three ovarian cancer cell liues and epithelial ovarian cancer tissues from 20 patients. After transforming an expression plasmid of C-CPE-ETA′ into E. coli BL21(DE3)plysS strain, the recombinant protein was purified using His-Bind resin chromatography column and analyzed by Western blot and Coomassie blue staining. The specific binding, proapoptotic and cytolytic activities were evaluated by flow cytometry, fluorescence microscopy with the JC-1 probe and MTT assay in CLDN-3,4-overexpressing ovarian cancer cells. Results Quantitive RT-PCR results showed there existed high levels of CLDN-3 and CLDN-4 in ovarian cancer cells, CAOV3,OVCAR3 and SKOV3. Moreover, high expressions of CLDN-3 and CLDN-4 were observed in 90.0%(18/20)and 60.0%(12/20)of ovarian cancer tissues, with an expression level 10-fold higher than that in the normal ovarian tissue. A 58 000 recombinant protein C-CPE-ETA′ was demonstrated by Western blot and Coomassie blue staining. Purified and recombinant C-CPE-ETA' was bound with high affinity to CLDN-3,4-overexpressing ovarian cancer cells, CAOV3, OVCAR3 and SKOV3 cells. C-CPE-ETA′ was strongly proapoptotic and cytotoxic towards the CLDN-3,4-overexpressing ovarian cancer cells. The concentration of IC50 was 7. 364 ng/ml for CAOV3 cells, 8.110 ng/ml for OVCAR3 cells and 22. 340 ng/ml for SKOV3cells, respectively. However, control CLDN-3,4-deficient cell line HUVEC was not susceptible to the recombinant C-CPE-ETA' at a concentration up to 10 μg/ml. Conclusions The C-CPE-ETA' protein exhibits

  19. Myc overexpression enhances of epicardial contribution to the developing heart and promotes extensive expansion of the cardiomyocyte population

    Science.gov (United States)

    Villa del Campo, Cristina; Lioux, Ghislaine; Carmona, Rita; Sierra, Rocío; Muñoz-Chápuli, Ramón; Clavería, Cristina; Torres, Miguel

    2016-01-01

    Myc is an essential regulator of cell growth and proliferation. Myc overexpression promotes the homeostatic expansion of cardiomyocyte populations by cell competition, however whether this applies to other cardiac lineages remains unknown. The epicardium contributes signals and cells to the developing and adult injured heart and exploring strategies for modulating its activity is of great interest. Using inducible genetic mosaics, we overexpressed Myc in the epicardium and determined the differential expansion of Myc-overexpressing cells with respect to their wild type counterparts. Myc-overexpressing cells overcolonized all epicardial-derived lineages and showed increased ability to invade the myocardium and populate the vasculature. We also found massive colonization of the myocardium by Wt1Cre-derived Myc-overexpressing cells, with preservation of cardiac development. Detailed analyses showed that this contribution is unlikely to derive from Cre activity in early cardiomyocytes but does not either derive from established epicardial cells, suggesting that early precursors expressing Wt1Cre originate the recombined cardiomyocytes. Myc overexpression does not modify the initial distribution of Wt1Cre-recombined cardiomyocytes, indicating that it does not stimulate the incorporation of early expressing Wt1Cre lineages to the myocardium, but differentially expands this initial population. We propose that strategies using epicardial lineages for heart repair may benefit from promoting cell competitive ability. PMID:27752085

  20. PEP3 overexpression shortens lag phase but does not alter growth rate in Saccharomyces cerevisiae exposed to acetic acid stress.

    Science.gov (United States)

    Ding, Jun; Holzwarth, Garrett; Bradford, C Samuel; Cooley, Ben; Yoshinaga, Allen S; Patton-Vogt, Jana; Abeliovich, Hagai; Penner, Michael H; Bakalinsky, Alan T

    2015-10-01

    In fungi, two recognized mechanisms contribute to pH homeostasis: the plasma membrane proton-pumping ATPase that exports excess protons and the vacuolar proton-pumping ATPase (V-ATPase) that mediates vacuolar proton uptake. Here, we report that overexpression of PEP3 which encodes a component of the HOPS and CORVET complexes involved in vacuolar biogenesis, shortened lag phase in Saccharomyces cerevisiae exposed to acetic acid stress. By confocal microscopy, PEP3-overexpressing cells stained with the vacuolar membrane-specific dye, FM4-64 had more fragmented vacuoles than the wild-type control. The stained overexpression mutant was also found to exhibit about 3.6-fold more FM4-64 fluorescence than the wild-type control as determined by flow cytometry. While the vacuolar pH of the wild-type strain grown in the presence of 80 mM acetic acid was significantly higher than in the absence of added acid, no significant difference was observed in vacuolar pH of the overexpression strain grown either in the presence or absence of 80 mM acetic acid. Based on an indirect growth assay, the PEP3-overexpression strain exhibited higher V-ATPase activity. We hypothesize that PEP3 overexpression provides protection from acid stress by increasing vacuolar surface area and V-ATPase activity and, hence, proton-sequestering capacity.

  1. Transgenic cloned sheep overexpressing ovine toll-like receptor 4.

    Science.gov (United States)

    Deng, Shoulong; Li, Guiguan; Zhang, Jinlong; Zhang, Xiaosheng; Cui, Maosheng; Guo, Yong; Liu, Guoshi; Li, Guangpeng; Feng, Jianzhong; Lian, Zhengxing

    2013-07-01

    An ovine fetal fibroblast cell line highly expressing TLR4 was established by inserting TLR4 into a reconstructive p3S-LoxP plasmid. Transgenic sheep overexpressing TLR4 were produced by transferring TLR4-transfected fetal fibroblasts into metaphase (M)II-stage enucleated oocytes (using SCNT). Because reconstructed embryos derived from MII-stage enucleated oocytes matured in vivo using a delayed-activated method had a higher pregnancy rate (18.52%) than that from MII-stage enucleated oocytes matured in vitro, the former procedure was used. Nine TLR4-transgenic live births were confirmed using polymerase chain reaction and Southern blot analysis. Increased expression of TLR4 at mRNA and protein levels in ear tissues of transgenic lambs were verified using reverse transcription polymerase chain reaction and immunohistochemistry, respectively. More toll-like receptor 4 protein was expressed by peripheral blood monocytes and/or macrophages collected from 3-month-old TLR4-transgenic than nontransgenic lambs at 0, 1, and 4 hours after lipopolysaccharide stimulation. Furthermore, interferon-γ and tumor necrosis factor α secreted by monocytes and/or macrophages of TLR4-transgenic lambs were significantly higher at 1 hour. Therefore, lipopolysaccharide-induced inflammatory responses from monocytes and/or macrophages occurred sooner in TLR4-transgenic lambs, consistent with an enhanced host immune response. In conclusion, transgenic sheep overexpressing TLR4 are a primary model to investigate the role of transgenic animals in disease resistance and have potential for breeding sheep with disease resistance.

  2. Cellular receptors for plasminogen activators recent advances.

    Science.gov (United States)

    Ellis, V

    1997-10-01

    The generation of the broad-specificity protease plasmin by the plasminogen activators urokinase-type plasminogen activator (uPA) and tissue-type plasminogen activator (tPA) is implicated in a variety of pathophysiological processes, including vascular fibrin dissolution, extracellular matrix degradation and remodeling, and cell migration. A mechanism for the regulation of plasmin generation is through binding of the plasminogen activators to specific cellular receptors: uPA to the glycolipid-anchored membrane protein urokinase-type plasminogen activator receptor (uPAR) and tPA to a number of putative binding sites. The uPA-uPAR complex can interact with a variety of ligands, including plasminogen, vitronectin, and integrins, indicating a multifunctional role for uPAR, regulating not only efficient and spatially restricted plasmin generation but also having the potential to modulate cell adhesion and signal transduction. The cellular binding of tPA, although less well characterized, also has the capacity to regulate plasmin generation and to play a significant role in vessel-wall biology. (Trends Cardiovasc Med 1997;7:227-234). © 1997, Elsevier Science Inc.

  3. Overexpression of mitochondrial sirtuins alters glycolysis and mitochondrial function in HEK293 cells.

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    Michelle Barbi de Moura

    Full Text Available SIRT3, SIRT4, and SIRT5 are mitochondrial deacylases that impact multiple facets of energy metabolism and mitochondrial function. SIRT3 activates several mitochondrial enzymes, SIRT4 represses its targets, and SIRT5 has been shown to both activate and repress mitochondrial enzymes. To gain insight into the relative effects of the mitochondrial sirtuins in governing mitochondrial energy metabolism, SIRT3, SIRT4, and SIRT5 overexpressing HEK293 cells were directly compared. When grown under standard cell culture conditions (25 mM glucose all three sirtuins induced increases in mitochondrial respiration, glycolysis, and glucose oxidation, but with no change in growth rate or in steady-state ATP concentration. Increased proton leak, as evidenced by oxygen consumption in the presence of oligomycin, appeared to explain much of the increase in basal oxygen utilization. Growth in 5 mM glucose normalized the elevations in basal oxygen consumption, proton leak, and glycolysis in all sirtuin over-expressing cells. While the above effects were common to all three mitochondrial sirtuins, some differences between the SIRT3, SIRT4, and SIRT5 expressing cells were noted. Only SIRT3 overexpression affected fatty acid metabolism, and only SIRT4 overexpression altered superoxide levels and mitochondrial membrane potential. We conclude that all three mitochondrial sirtuins can promote increased mitochondrial respiration and cellular metabolism. SIRT3, SIRT4, and SIRT5 appear to respond to excess glucose by inducing a coordinated increase of glycolysis and respiration, with the excess energy dissipated via proton leak.

  4. Urokinase-targeted recombinant bacterial protein toxins-a rationally designed and engineered anticancer agent for cancer therapy

    Institute of Scientific and Technical Information of China (English)

    Yizhen LIU; Shi-Yan LI

    2009-01-01

    Urokinase-targeted recombinant bacterial protein toxins are a sort of rationally designed and engineered anticancer recombinant fusion proteins representing a novel class of agents for cancer therapy.Bacterial protein toxins have long been known as the primary virulence factor(s) for a variety of pathogenic bacteria and are the most powerful human poisons.On the other hand,it has been well documented that urokinase-type plasminogen activator (uPA) and urokinase plasminogen activator receptor (uPAR),making up the uPA system,are overexpressed in a variety of human tumors and tumor cell lines.The expression of uPA system is highly correlated with tumor invasion and metastasis.To exploit these characteristics in the design of tumor cell-selective cytotoxins,two prominent bacterial protein toxins,i.e.,the diphtheria toxin and anthrax toxin are deliberately engineered through placing a sequence targeted specifically by the uPA system to form anticancer recombinant fusion proteins.These uPA system-targeted bacterial protein toxins are activated selectively on the surface of uPA systemexpressing tumor cells,thereby killing these cells.This article provides a review on the latest progress in the exploitation of these recombinant fusion proteins as potent tumoricidal agents.It is perceptible that the strategies for cancer therapy are being innovated by this novel therapeutic approach.

  5. Overexpression of human and fly frataxins in Drosophila provokes deleterious effects at biochemical, physiological and developmental levels.

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    Juan A Navarro

    Full Text Available BACKGROUND: Friedreich's ataxia (FA, the most frequent form of inherited ataxias in the Caucasian population, is caused by a reduced expression of frataxin, a highly conserved protein. Model organisms have contributed greatly in the efforts to decipher the function of frataxin; however, the precise function of this protein remains elusive. Overexpression studies are a useful approach to investigate the mechanistic actions of frataxin; however, the existing literature reports contradictory results. To further investigate the effect of frataxin overexpression, we analyzed the consequences of overexpressing human (FXN and fly (FH frataxins in Drosophila. METHODOLOGY/PRINCIPAL FINDINGS: We obtained transgenic flies that overexpressed human or fly frataxins in a general pattern and in different tissues using the UAS-GAL4 system. For both frataxins, we observed deleterious effects at the biochemical, histological and behavioral levels. Oxidative stress is a relevant factor in the frataxin overexpression phenotypes. Systemic frataxin overexpression reduces Drosophila viability and impairs the normal embryonic development of muscle and the peripheral nervous system. A reduction in the level of aconitase activity and a decrease in the level of NDUF3 were also observed in the transgenic flies that overexpressed frataxin. Frataxin overexpression in the nervous system reduces life span, impairs locomotor ability and causes brain degeneration. Frataxin aggregation and a misfolding of this protein have been shown not to be the mechanism that is responsible for the phenotypes that have been observed. Nevertheless, the expression of human frataxin rescues the aconitase activity in the fh knockdown mutant. CONCLUSION/SIGNIFICANCE: Our results provide in vivo evidence of a functional equivalence for human and fly frataxins and indicate that the control of frataxin expression is important for treatments that aim to increase frataxin levels.

  6. Overexpression of Human and Fly Frataxins in Drosophila Provokes Deleterious Effects at Biochemical, Physiological and Developmental Levels

    Science.gov (United States)

    Soriano, Sirena; Botella, José A.; Schneuwly, Stephan; Martínez-Sebastián, María J.; Moltó, María D.

    2011-01-01

    Background Friedreich's ataxia (FA), the most frequent form of inherited ataxias in the Caucasian population, is caused by a reduced expression of frataxin, a highly conserved protein. Model organisms have contributed greatly in the efforts to decipher the function of frataxin; however, the precise function of this protein remains elusive. Overexpression studies are a useful approach to investigate the mechanistic actions of frataxin; however, the existing literature reports contradictory results. To further investigate the effect of frataxin overexpression, we analyzed the consequences of overexpressing human (FXN) and fly (FH) frataxins in Drosophila. Methodology/Principal Findings We obtained transgenic flies that overexpressed human or fly frataxins in a general pattern and in different tissues using the UAS-GAL4 system. For both frataxins, we observed deleterious effects at the biochemical, histological and behavioral levels. Oxidative stress is a relevant factor in the frataxin overexpression phenotypes. Systemic frataxin overexpression reduces Drosophila viability and impairs the normal embryonic development of muscle and the peripheral nervous system. A reduction in the level of aconitase activity and a decrease in the level of NDUF3 were also observed in the transgenic flies that overexpressed frataxin. Frataxin overexpression in the nervous system reduces life span, impairs locomotor ability and causes brain degeneration. Frataxin aggregation and a misfolding of this protein have been shown not to be the mechanism that is responsible for the phenotypes that have been observed. Nevertheless, the expression of human frataxin rescues the aconitase activity in the fh knockdown mutant. Conclusion/Significance Our results provide in vivo evidence of a functional equivalence for human and fly frataxins and indicate that the control of frataxin expression is important for treatments that aim to increase frataxin levels. PMID:21779322

  7. Enhanced Arabidopsis pattern-triggered immunity by overexpression of cysteine-rich receptor-like kinases

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    Yu-Hung eYeh

    2015-05-01

    Full Text Available Upon recognition of microbe-associated molecular patterns (MAMPs such as the bacterial flagellin (or the derived peptide flg22 by pattern-recognition receptors (PRRs such as the FLAGELLIN SENSING2 (FLS2, plants activate the pattern-triggered immunity (PTI response. The L-type lectin receptor kinase-VI.2 (LecRK-VI.2 is a positive regulator of Arabidopsis thaliana PTI. Cysteine-rich receptor-like kinases (CRKs possess two copies of the C-X8-C-X2-C (DUF26 motif in their extracellular domains and are thought to be involved in plant stress resistance, but data about CRK functions are scarce. Here we show that Arabidopsis overexpressing the LecRK-VI.2-responsive CRK4, CRK6 and CRK36 demonstrated an enhanced PTI response and were resistant to virulent bacteria Pseudomonas syringae pv. tomato DC3000. Notably, the flg22-triggered oxidative burst was primed in CRK4, CRK6, and CRK36 transgenics and up-regulation of the PTI-responsive gene FLG22-INDUCED RECEPTOR-LIKE 1 (FRK1 was potentiated upon flg22 treatment in CRK4 and CRK6 overexpression lines or constitutively increased by CRK36 overexpression. PTI-mediated callose deposition was not affected by overexpression of CRK4 and CRK6, while CRK36 overexpression lines demonstrated constitutive accumulation of callose. In addition, Pst DC3000-mediated stomatal reopening was blocked in CRK4 and CRK36 overexpression lines, while overexpression of CRK6 induced constitutive stomatal closure suggesting a strengthening of stomatal immunity. Finally, bimolecular fluorescence complementation and co-immunoprecipitation analyses in Arabidopsis protoplasts suggested that the plasma membrane localized CRK4, CRK6 and CRK36 associate with the PRR FLS2. Association with FLS2 and the observation that overexpression of CRK4, CRK6, and CRK36 boosts specific PTI outputs and resistance to bacteria suggest a role for these CRKs in Arabidopsis innate immunity.

  8. Cardiac muscarinic receptor overexpression in sudden infant death syndrome.

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    Angelo Livolsi

    Full Text Available BACKGROUND: Sudden infant death syndrome (SIDS remains the leading cause of death among infants less than 1 year of age. Disturbed expression of some neurotransmitters and their receptors has been shown in the central nervous system of SIDS victims but no biological abnormality of the peripheral vago-cardiac system has been demonstrated to date. The present study aimed to seek vago-cardiac abnormalities in SIDS victims. The cardiac level of expression of muscarinic receptors, as well as acetylcholinesterase enzyme activity were investigated. METHODOLOGY/PRINCIPAL FINDINGS: Left ventricular samples and blood samples were obtained from autopsies of SIDS and children deceased from non cardiac causes. Binding experiments performed with [(3H]NMS, a selective muscarinic ligand, in cardiac membrane preparations showed that the density of cardiac muscarinic receptors was increased as shown by a more than doubled B(max value in SIDS (n = 9 SIDS versus 8 controls. On average, the erythrocyte acetylcholinesterase enzyme activity was also significantly increased (n = 9 SIDS versus 11 controls. CONCLUSIONS: In the present study, it has been shown for the first time that cardiac muscarinic receptor overexpression is associated with SIDS. The increase of acetylcholinesterase enzyme activity appears as a possible regulatory mechanism.

  9. Ras1CA overexpression in the posterior silk gland improves silk yield

    Institute of Scientific and Technical Information of China (English)

    Li Ma; Hanfu Xu; Jinqi Zhu; Sanyuan Ma; Yan Liu; Rong-Jing Jiang; Qingyou Xia; Sheng Li

    2011-01-01

    Sericulture has been greatly advanced by applying hybrid breeding techniques to the domesticated silkworm,Bombyx mori,but has reached a plateau during the last decades. For the first time,we report improved silk yield in a GAL4/UAS transgenic silkworm. Overexpression of the Ras1CA oncogene specifically in the posterior silk gland improved fibroin production and silk yield by 60%,while increasing food consumption by only 20%. Ras activation by Ras1CA overexpression in the posterior silk gland enhanced phosphorylation levels of Ras downstream effector proteins,up-regulated fibroin mRNA levels,increased total DNA content,and stimulated endoreplication. Moreover,Rasl activation increased cell and nuclei sizes,enriched subcellular organelles related to protein synthesis,and stimulated ribosome biogenesis for mRNA translation. We conclude that Rasl activation increases cell size and protein synthesis in the posterior silk gland,leading to silk yield improvement.

  10. Contribution of macrophages to plasmin activity in ewe bulk milk

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    M. Albenzio

    2010-04-01

    Full Text Available A total of 225 bulk sheep milk samples were collected throughout lactation to assess the contribution of macrophages to the regulation of the plasmin/plasminogen system. Samples were analyzed for composition, milk renneting parameters, and for activities of plasmin (PL, plasminogen (PG and plasminogen activators (PA. Isolation of macrophages from milk was performed using a magnetic positive separation; separated cells were lysed and activity of urokinase-PA was determined. PL activity in milk decreased during lactation (P < 0.001. The reduction in plasmin activity recorded in the mid and late lactation milk matched with the increase in PG/PL ratio (P < 0.001. The activity of PA increased throughout lactation (P < 0.001, the highest value being recorded in the late lactation milk.The amount of isolated and concentrated macrophages was higher in early and mid lactation milk than in late lactation milk (P < 0.01. Stage of lactation did not influence the activity of u-PA detected in isolated macrophages. The activity of u-PA associated with macrophages was lower than total PA activity detected in milk. Our results lend support to the hypothesis that in ewe bulk milk from healthy flocks macrophages only slightly contributed to the activation of plasmin/plasminogen system.

  11. Overexpression of phosphomimic mutated OsWRKY53 leads to enhanced blast resistance in rice.

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    Tetsuya Chujo

    Full Text Available WRKY transcription factors and mitogen-activated protein kinase (MAPK cascades have been shown to play pivotal roles in the regulation of plant defense responses. We previously reported that OsWRKY53-overexpressing rice plants showed enhanced resistance to the rice blast fungus. In this study, we identified OsWRKY53 as a substrate of OsMPK3/OsMPK6, components of a fungal PAMP-responsive MAPK cascade in rice, and analyzed the effect of OsWRKY53 phosphorylation on the regulation of basal defense responses to a virulence race of rice blast fungus Magnaporthe oryzae strain Ina86-137. An in vitro phosphorylation assay revealed that the OsMPK3/OsMPK6 activated by OsMKK4 phosphorylated OsWRKY53 recombinant protein at its multiple clustered serine-proline residues (SP cluster. When OsWRKY53 was coexpressed with a constitutively active mutant of OsMKK4 in a transient reporter gene assay, the enhanced transactivation activity of OsWRKY53 was found to be dependent on phosphorylation of the SP cluster. Transgenic rice plants overexpressing a phospho-mimic mutant of OsWRKY53 (OsWRKY53SD showed further-enhanced disease resistance to the blast fungus compared to native OsWRKY53-overexpressing rice plants, and a substantial number of defense-related genes, including pathogenesis-related protein genes, were more upregulated in the OsWRKY53SD-overexpressing plants compared to the OsWRKY53-overexpressing plants. These results strongly suggest that the OsMKK4-OsMPK3/OsMPK6 cascade regulates transactivation activity of OsWRKY53, and overexpression of the phospho-mimic mutant of OsWRKY53 results in a major change to the rice transcriptome at steady state that leads to activation of a defense response against the blast fungus in rice plants.

  12. Conditional astroglial Rictor overexpression induces malignant glioma in mice.

    Directory of Open Access Journals (Sweden)

    Tariq Bashir

    Full Text Available BACKGROUND: Hyperactivation of the mTORC2 signaling pathway has been shown to contribute to the oncogenic properties of gliomas. Moreover, overexpression of the mTORC2 regulatory subunit Rictor has been associated with increased proliferation and invasive character of these tumor cells. METHODOLOGY/PRINCIPAL FINDINGS: To determine whether Rictor overexpression was sufficient to induce glioma formation in mice, we inserted a Cre-lox-regulated human Rictor transgene into the murine ROSA26 locus. This floxed Rictor strain was crossed with mice expressing the Cre recombinase driven from the glial fibrillary acidic protein (GFAP promoter whose expression is limited to the glial cell compartment. Double transgenic GFAP-Cre/Rictor(loxP/loxP mice developed multifocal infiltrating glioma containing elevated mTORC2 activity and typically involved the subventricular zone (SVZ and lateral ventricle. Analysis of Rictor-dependent signaling in these tumors demonstrated that in addition to elevated mTORC2 activity, an mTORC2-independent marker of cortical actin network function, was also elevated. Upon histological examination of the neoplasms, many displayed oligodendroglioma-like phenotypes and expressed markers associated with oligodendroglial lineage tumors. To determine whether upstream oncogenic EGFRvIII signaling would alter tumor phenotypes observed in the GFAP-Cre/Rictor(loxP/loxP mice, transgenic GFAP-EGFRvIII; GFAP-Cre/Rictor(loxP/loxP mice were generated. These mice developed mixed astrocytic-oligodendroglial tumors, however glioma formation was accelerated and correlated with increased mTORC2 activity. Additionally, the subventricular zone within the GFAP-Cre/Rictor(loxP/loxP mouse brain was markedly expanded, and a further proliferation within this compartment of the brain was observed in transgenic GFAP-EGFRvIII; GFAP-Cre/Rictor(loxP/loxP mice. CONCLUSION/SIGNIFICANCE: These data collectively establish Rictor as a novel oncoprotein and support

  13. Conditional Astroglial Rictor Overexpression Induces Malignant Glioma in Mice

    Science.gov (United States)

    Bashir, Tariq; Cloninger, Cheri; Artinian, Nicholas; Anderson, Lauren; Bernath, Andrew; Holmes, Brent; Benavides-Serrato, Angelica; Sabha, Nesrin; Nishimura, Robert N.; Guha, Abhijit; Gera, Joseph

    2012-01-01

    Background Hyperactivation of the mTORC2 signaling pathway has been shown to contribute to the oncogenic properties of gliomas. Moreover, overexpression of the mTORC2 regulatory subunit Rictor has been associated with increased proliferation and invasive character of these tumor cells. Methodology/Principal Findings To determine whether Rictor overexpression was sufficient to induce glioma formation in mice, we inserted a Cre-lox-regulated human Rictor transgene into the murine ROSA26 locus. This floxed Rictor strain was crossed with mice expressing the Cre recombinase driven from the glial fibrillary acidic protein (GFAP) promoter whose expression is limited to the glial cell compartment. Double transgenic GFAP-Cre/RictorloxP/loxP mice developed multifocal infiltrating glioma containing elevated mTORC2 activity and typically involved the subventricular zone (SVZ) and lateral ventricle. Analysis of Rictor-dependent signaling in these tumors demonstrated that in addition to elevated mTORC2 activity, an mTORC2-independent marker of cortical actin network function, was also elevated. Upon histological examination of the neoplasms, many displayed oligodendroglioma-like phenotypes and expressed markers associated with oligodendroglial lineage tumors. To determine whether upstream oncogenic EGFRvIII signaling would alter tumor phenotypes observed in the GFAP-Cre/RictorloxP/loxP mice, transgenic GFAP-EGFRvIII; GFAP-Cre/RictorloxP/loxP mice were generated. These mice developed mixed astrocytic-oligodendroglial tumors, however glioma formation was accelerated and correlated with increased mTORC2 activity. Additionally, the subventricular zone within the GFAP-Cre/RictorloxP/loxP mouse brain was markedly expanded, and a further proliferation within this compartment of the brain was observed in transgenic GFAP-EGFRvIII; GFAP-Cre/RictorloxP/loxP mice. Conclusion/Significance These data collectively establish Rictor as a novel oncoprotein and support the role of dysregulated

  14. CDC25B overexpression stabilises centrin 2 and promotes the formation of excess centriolar foci.

    Directory of Open Access Journals (Sweden)

    Rose Boutros

    Full Text Available CDK-cyclin complexes regulate centriole duplication and microtubule nucleation at specific cell cycle stages, although their exact roles in these processes remain unclear. As the activities of CDK-cyclins are themselves positively regulated by CDC25 phosphatases, we investigated the role of centrosomal CDC25B during interphase. We report that overexpression of CDC25B, as is commonly found in human cancer, results in a significant increase in centrin 2 at the centrosomes of interphase cells. Conversely, CDC25B depletion causes a loss of centrin 2 from the centrosome, which can be rescued by treatment with the proteasome inhibitor MG132. CDC25B overexpression also promotes the formation of excess centrin 2 "foci". These foci can accumulate other centrosome proteins, including γ-tubulin and PCM-1, and can function as microtubule organising centres, indicating that these represent functional centrosomes. Formation of centrin 2 foci can be blocked by specific inhibition of CDK2 but not CDK1. CDK2-mediated phosphorylation of Monopolar spindle 1 (Mps1 at the G1/S transition is essential for the initiation of centrosome duplication, and Mps1 is reported to phosphorylate centrin 2. Overexpression of wild-type or non-degradable Mps1 exacerbated the formation of excess centrin 2 foci induced by CDC25B overexpression, while kinase-dead Mps1 has a protective effect. Together, our data suggest that CDC25B, through activation of a centrosomal pool of CDK2, stabilises the local pool of Mps1 which in turn regulates the level of centrin 2 at the centrosome. Overexpression of CDC25B may therefore contribute to tumourigenesis by perturbing the natural turnover of centrosome proteins such as Mps1 and centrin 2, thus resulting in the de novo assembly of extra-numerary centrosomes and potentiating chromosome instability.

  15. Inhibition of ERBB2-overexpressing Tumors by Recombinant Human Prolidase and Its Enzymatically Inactive Mutant

    Directory of Open Access Journals (Sweden)

    Lu Yang

    2015-05-01

    Full Text Available ERBB2 is an oncogenic receptor tyrosine kinase overexpressed in a subset of human breast cancer and other cancers. We recently found that human prolidase (PEPD, a dipeptidase, is a high affinity ERBB2 ligand and cross-links two ERBB2 monomers. Here, we show that recombinant human PEPD (rhPEPD strongly inhibits ERBB2-overexpressing tumors in mice, whereas it does not impact tumors without ERBB2 overexpression. rhPEPD causes ERBB2 depletion, disrupts oncogenic signaling orchestrated by ERBB2 homodimers and heterodimers, and induces apoptosis. The impact of enzymatically-inactive mutant rhPEPDG278D on ERBB2 is indistinguishable from that of rhPEPD, but rhPEPDG278D is superior to rhPEPD for tumor inhibition. The enzymatic function of rhPEPD stimulates HIF-1α and other pro-survival factors in tumors, which likely attenuates its antitumor activity. rhPEPDG278D is also attractive in that it may not interfere with the physiologic function of endogenous PEPD in normal cells. Collectively, we have identified a human protein as an inhibitory ERBB2 ligand that inhibits ERBB2-overexpressing tumors in vivo. Several anti-ERBB2 agents are on the market but are hampered by drug resistance and high drug cost. rhPEPDG278D may synergize with these agents and may also be highly cost-effective, since it targets ERBB2 with a different mechanism and can be produced in bacteria.

  16. erbB2 Overexpression in Uterine Serous Cancer: A Molecular Target for Trastuzumab Therapy

    Directory of Open Access Journals (Sweden)

    Karim S. ElSahwi

    2011-01-01

    Full Text Available Endometrial cancer is the most common female genital tract malignancy in the United States. Type I endometrial cancer is usually diagnosed at an early stage, and has a good prognosis. Type II is very aggressive, and is responsible for most uterine cancer relapses and deaths. Uterine serous adenocarcinomas (USC constitute the majority of Type II variants. They have a higher propensity for lymph node and distant metastases. They are frequently aneuploid and associated with p53 mutations. erbB2 overexpression in USC has been described. The incidence, which is higher in African Americans, ranges from 18–80%. erbB2 overexpression was found to be associated with higher stage, chemoresistance, and worse survival. Trastuzumab a humanized mAb was approved by the FDA for treatment of breast cancers that overexpress erbB2 in combination with standard chemotherapy. Evidence of trastuzumab activity in USC has been reported in vitro, as well as in case reports of advanced and recurrent cases. Promising results were obtained in these heavily pretreated patients either with trastuzumab alone or in combination with chemotherapy. This supports the hypothesis that trastuzumab may very well be an attractive and viable treatment option for advanced stage USC tumors that overexpress the erbB2, and is worthy of further study.

  17. Improved antibody production in Chinese hamster ovary cells by ATF4 overexpression.

    Science.gov (United States)

    Haredy, Ahmad M; Nishizawa, Akitoshi; Honda, Kohsuke; Ohya, Tomoshi; Ohtake, Hisao; Omasa, Takeshi

    2013-12-01

    To improve antibody production in Chinese hamster ovary (CHO) cells, the humanized antibody-producing CHO DP-12-SF cell line was transfected with the gene encoding activating transcription factor 4 (ATF4), a central factor in the unfolded protein response. Overexpression of ATF4 significantly enhanced the production of antibody in the CHO DP-12-SF cell line. The specific IgG production rate of in the ATF4-overexpressing CHO-ATF4-16 cells was approximately 2.4 times that of the parental host cell line. Clone CHO-ATF4-16 did not show any change in growth rate compared with the parental cells or mock-transfected CHO-DP12-SF cells. The expression levels of mRNAs encoding both the antibody heavy and light chains in the CHO-ATF4-16 clone were analyzed. This analysis showed that ATF4 overexpression improved the total production and specific production rate of antibody without affecting the mRNA transcription level. These results indicate that ATF4 overexpression is a promising method for improving recombinant IgG production in CHO cells.

  18. Engineering overexpression of ORCA3 and strictosidine glucosidase in Catharanthus roseus hairy roots increases alkaloid production.

    Science.gov (United States)

    Sun, Jiayi; Peebles, Christie A M

    2016-09-01

    Catharanthus roseus produces many pharmaceutically important terpenoid indole alkaloids (TIAs) such as vinblastine, vincristine, ajmalicine, and serpentine. Past metabolic engineering efforts have pointed to the tight regulation of the TIA pathway and to multiple rate-limiting reactions. Transcriptional regulator ORCA3 (octadecanoid responsive Catharanthus AP2-domain protein), activated by jasmonic acid, plays a central role in regulating the TIA pathway. In this study, overexpressing ORCA3 under the control of a glucocorticoid-inducible promoter in C. roseus hairy roots resulted in no change in the total amount of TIAs measured. RT-qPCR results showed that ORCA3 overexpression triggered the upregulation of transcripts of most of the known TIA pathway genes. One notable exception was the decrease in strictosidine glucosidase (SGD) transcripts. These results corresponded to previously published results. In this study, ORCA3 and SGD were both engineered in hairy roots under the control of a glucocorticoid-inducible promoter. Co-overexpression of ORCA3 and SGD resulted in a significant (p < 0.05) increase in serpentine by 44 %, ajmalicine by 32 %, catharanthine by 38 %, tabersonine by 40 %, lochnericine by 60 % and hörhammericine by 56 % . The total alkaloid pool was increased significantly by 47 %. Thus, combining overexpression of a positive regulator and a pathway gene which is not controlled by this regulator provided a way to enhance alkaloid production.

  19. Overexpression and topology of bacterial oligosaccharyltransferase PglB

    Energy Technology Data Exchange (ETDEWEB)

    Li, Lei [National Glycoengineering Research Center and The State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Shandong 250100 (China); Departments of Biochemistry and Chemistry, The Ohio State University, Columbus, OH 43210 (United States); Woodward, Robert [Departments of Biochemistry and Chemistry, The Ohio State University, Columbus, OH 43210 (United States); Ding, Yan; Liu, Xian-wei [National Glycoengineering Research Center and The State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Shandong 250100 (China); Yi, Wen; Bhatt, Veer S. [Departments of Biochemistry and Chemistry, The Ohio State University, Columbus, OH 43210 (United States); Chen, Min [National Glycoengineering Research Center and The State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Shandong 250100 (China); Zhang, Lian-wen [College of Pharmacy, Nankai University, Tianjin 300071 (China); Wang, Peng George, E-mail: wang.892@osu.edu [National Glycoengineering Research Center and The State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Shandong 250100 (China); Departments of Biochemistry and Chemistry, The Ohio State University, Columbus, OH 43210 (United States)

    2010-04-16

    Campylobacter jejuni contains a post-translational N-glycosylation system in which a STT3 homologue, PglB, functions as the oligosaccharyltransferase. Herein, we established a method for obtaining relatively large quantities of homogenous PglB proteins. PglB was overexpressed in Escherichia coli C43(DE3) at a level of 1 mg/L cell cultures. The activity of purified PglB was verified using a chemically synthesized sugar donor: N-acetylgalactosamine-diphospho-undecaprenyl (GalNAc-PP-Und) and a synthesized peptide acceptor. The result confirms that PglB is solely responsible for the oligosaccharyltransferase activity and complements the finding that PglB exhibits relaxed sugar substrate specificity. In addition, we performed the topology mapping of PglB using the PhoA/LacZ fusion method. The topological model shows that PglB possesses 11 transmembrane segments and two relatively large periplasmic regions other than the C-terminal domain, which is consistent with the proposal of the common N{sub cyt}-C{sub peri} topology with 11 transmembrane segments for the STT3 family proteins.

  20. Brak skuteczności leczenia zespołów bólowych kręgosłupa za pomocą laseroterapii i fali ultradźwiękowej = Lack of efficacy of laser therapy and ultrasound for low back pain

    OpenAIRE

    2016-01-01

    Kocjan Janusz. Brak skuteczności leczenia zespołów bólowych kręgosłupa za pomocą laseroterapii i fali ultradźwiękowej = Lack of efficacy of laser therapy and ultrasound for low back pain. Journal of Education, Health and Sport. 2016;6(9):323-332. eISSN 2391-8306. DOI http://dx.doi.org/10.5281/zenodo.61876 http://ojs.ukw.edu.pl/index.php/johs/article/view/3805       The journal has had 7 points in Ministry of Science and Higher Education paramet...

  1. Asbestos exposure increases human bronchial epithelial cell fibrinolytic activity.

    Science.gov (United States)

    Gross, T J; Cobb, S M; Gruenert, D C; Peterson, M W

    1993-03-01

    Chronic exposure to asbestos fibers results in fibrotic lung disease. The distal pulmonary epithelium is an early target of asbestos-mediated injury. Local plasmin activity may be important in modulating endoluminal inflammatory responses in the lung. We studied the effects of asbestos exposure on cell-mediated plasma clot lysis as a marker of pericellular plasminogen activation. Exposing human bronchial epithelial (HBE) cells to 100 micrograms/ml of asbestos fibers for 24 h resulted in increased plasma clot lysis. Fibrinolytic activity was augmented in a dose-dependent fashion, was not due to secreted protease, and occurred only when there was direct contact between the plasma clot and the epithelial monolayer. Further analysis showed that asbestos exposure increased HBE cell-associated urokinase-type plasminogen activator (uPA) activity in a time-dependent manner. The increased cell-associated PA activity could be removed by acid washing. The increase in PA activity following asbestos exposure required new protein synthesis because it was abrogated by treatment with either cycloheximide or actinomycin D. Therefore, asbestos exposure increases epithelial-mediated fibrinolysis by augmenting expression of uPA activity at the cell surface by mechanisms that require new RNA and protein synthesis. These observations suggest a novel mechanism whereby exposure of the distal epithelium to inhaled particulates may result in a chronic inflammatory response that culminates in the development of fibrotic lung disease.

  2. Over-expressed CmbT multidrug resistance transporter improves the fitness of Lactococcus lactis

    Directory of Open Access Journals (Sweden)

    Filipić Brankica

    2013-01-01

    Full Text Available The influence of the over-expression of CmbT multidrug resistance transporter on the growth rate of Lactococcus lactis NZ9000 was studied. L. lactis is a lactic acid bacteria (LAB widely used as a starter culture in dairy industry. Recently characterized CmbT MDR transporter in L. lactis confers resistance to a wide variety of toxic compounds as well as to some clinically relevant antibiotics. In this study, the cmbT gene was over-expressed in the strain L. lactis NZ9000 in the presence of nisin inducer. Over-expression of the cmbT gene in L. lactis NZ9000 was followed by RT-PCR. The obtained results showed that the cmbT gene was successfully over-expressed by addition of sub-inhibitory amounts of nisin. Growth curves of L. lactis NZ9000/pCT50 over-expressing the cmbT gene and L. lactis NZ9000 control strain were followed in the rich medium as well as in the chemically defined medium in the presence solely of methionine (0.084 mM or mix of methionine and cysteine (8.4 mM and 8.2 mM, respectively. Resulting doubling times revealed that L. lactis NZ9000/pCT50 had higher growth rate comparing to the control strain. This could be a consequence of the CmbT efflux activity, which improves the fitness of the host bacterium through the elimination of toxic compounds from the cell.

  3. Overexpression of Histone Deacetylase 6 Enhances Resistance to Porcine Reproductive and Respiratory Syndrome Virus in Pigs

    Science.gov (United States)

    Li, Qiuyan; Li, Zhiguo; Wang, Meng; Liu, Lin; Tian, Kegong; Li, Ning

    2017-01-01

    Porcine reproductive and respiratory syndrome virus (PRRSV) is one of the most economically relevant viral pathogens in pigs and causes substantial losses in the pig industry worldwide each year. At present, PRRSV vaccines do not effectively prevent and control this disease. Consequently, it is necessary to develop new antiviral strategies to compensate for the inefficacy of the available vaccines. Histone deacetylase 6 (HDAC6) is an important member of the histone deacetylase family that is responsible for regulating many important biological processes. Studies have shown that HDAC6 has anti-viral activities during the viral life cycle. However, whether HDAC6 overexpression enhances resistance to PRRSV in pigs remains unknown. In this study, we used a somatic cell cloning method to produce transgenic (TG) pigs that constitutively overexpress porcine HDAC6. These TG pigs showed germ line transmission with continued overexpression of HDAC6. In vitro, virus-challenged porcine alveolar macrophages (PAMs) overexpressed HDAC6, which suppressed viral gene expression and PRRSV production. In vivo, resistance to PRRSV in TG pigs was evaluated by direct or cohabitation mediated infection with a highly pathogenic PRRSV (HP-PRRSV) strain. Compared with non-TG (NTG) siblings, TG pigs showed a significantly lower viral load in the lungs and an extended survival time after infection with HP-PRRSV via intramuscular injection. In the cohabitation study, NTG pigs housed with challenged NTG pigs exhibited significantly worse clinical symptoms than the other three in-contact groups. These results collectively suggest that HDAC6 overexpression enhances resistance to PRRSV infection both in vitro and in vivo. Our findings suggest the potential involvement of HDAC6 in the response to PRRSV, which will facilitate the development of novel therapies for PRRSV. PMID:28052127

  4. Purification and Refolding of Overexpressed Human Basic Fibroblast Growth Factor in Escherichia coli

    OpenAIRE

    2011-01-01

    International audience; This work describes the integration of expanded bed adsorption (EBA) and adsorptive protein refolding operations used to recover purified and biologically active human basic fibroblast growth factor from inclusion bodies expressed in E. coli. Insoluble overexpressed human basic fibroblast growth factor has been purified on CM Hyper Z matrix by expanded bed adsorption after isolation and solubilization in 8 M urea. The adsorption was made in expanded bed without clarifi...

  5. Method and tool for prognosticating HIV infection in a subject by measuring soluble urokinase plasminogen activator receptor, degradation products thereof, and urokinase plasminogen activator receptor

    DEFF Research Database (Denmark)

    2000-01-01

    Method of diagnosing and/or prognosticating HIV infection in a subject comprising the steps of: (a) performing in vitro a measurement of the level of a marker in the form of (i) urokinase plasminogen activator receptor (uPAR), (ii) soluble urokinase plasminogen activator receptor (suPAR), (iii......) urokinase-type plasminogen activator (uPA), (iv) one or more degradation products of (i), (ii), or (iii), and/or (v) an mRNA for (i), (ii) or (iii), in a biological fluid sample from a subject, and (b) using the measurement value obtained to evaluate the state of the subject....

  6. Proteome analysis of a Lactococcus lactis strain overexpressing gapA suggests that the gene product is an auxiliary glyceraldehyde 3-phosphate dehydrogenase

    DEFF Research Database (Denmark)

    Willemoës, Martin; Kilstrup, Mogens; Roepstorff, Peter;

    2002-01-01

    strain that overexpessed the gapA gene derived from MG1363 upon nisin induction. Compared to the wild-type, the overexpressing strain had a 3.4-fold elevated level of specific GAPDH activity when grown in the presence of nisin. In both MG1363 and the gapA overexpressing strain the GAPDH activity...

  7. Overexpression of vsr in Escherichia coli is mutagenic.

    Science.gov (United States)

    Doiron, K M; Viau, S; Koutroumanis, M; Cupples, C G

    1996-01-01

    Overexpression of vsr in Escherichia coli stimulates transition and frameshift mutations. The pattern of mutations suggests that mutagenesis is due to saturation or inactivation of dam-directed mismatch repair. PMID:8763960

  8. [Overexpression of FKS1 to improve yeast autolysis-stress].

    Science.gov (United States)

    Li, Jia; Wang, Jinjing; Li, Qi

    2015-09-01

    With the development of high gravity brewing, yeast cells are exposed to multiple brewing-associated stresses, such as increased osmotic pressure, enhanced alcohol concentration and nutritional imbalance. These will speed up yeast autolysis, which seriously influence beer flavor and quality. To increase yeast anti-autolytic ability, FKS1 overexpression strain was constructed by 18S rDNA. The concentration of β-1,3-glucan of overexpression strain was 62% higher than that of wild type strain. Meantime, FKS1 overexpression strain increased anti-stress ability at 8% ethanol, 0.4 mol/L NaCl and starvation stress. Under simulated autolysis, FKS1 showed good anti-autolytic ability by slower autolysis. These results confirms the potential of FKS1 overexpression to tackle yeast autolysis in high-gravity brewing.

  9. Plasminogen-independent initiation of the pro-urokinase activation cascade in vivo. Activation of pro-urokinase by glandular kallikrein (mGK-6) in plasminogen-deficient mice

    DEFF Research Database (Denmark)

    List, K; Jensen, Ole Nørregaard; Bugge, T H;

    2000-01-01

    kallikrein). The pro-uPA converting activity of the mGK-6 enzyme, as well as its ability to cleave a synthetic substrate for glandular kallikrein, was inhibited by the serine proteinase inhibitor leupeptin but not by other serine proteinase inhibitors such as aprotinin, antithrombin III, or alpha(1...... the cascade by activating pro-uPA. The urine from Plg -/- mice contained active two-chain uPA as well as a proteinase capable of activating exogenously added pro-uPA. The active component was purified and identified by mass spectrometry-based peptide mapping as mouse glandular kallikrein mGK-6 (true tissue...

  10. GH/STAT5 signaling during the growth period in livers of mice overexpressing GH.

    Science.gov (United States)

    Martinez, Carolina S; Piazza, Verónica G; Díaz, María E; Boparai, Ravneet K; Arum, Oge; Ramírez, María C; González, Lorena; Becú-Villalobos, Damasia; Bartke, Andrzej; Turyn, Daniel; Miquet, Johanna G; Sotelo, Ana I

    2015-04-01

    GH/STAT5 signaling is desensitized in the liver in adult transgenic mice overexpressing GH; however, these animals present greater body size. To assess whether the STAT5 pathway is active during the growth period in the liver in these animals, and how signaling modulators participate in this process, growing transgenic mice and normal siblings were evaluated. STAT5 does not respond to an acute GH-stimulus, but displays higher basal phosphorylation in the livers of growing GH-overexpressing mice. GH receptor and the positive modulators glucocorticoid receptor and HNF1 display greater abundance in transgenic animals, supporting the activity of STAT5. The negative modulators cytokine-induced suppressor and PTP1B are increased in GH-overexpressing mice. The suppressors SOCS2 and SOCS3 exhibit higher mRNA levels in transgenic mice but lower protein content, indicating that they are being actively degraded. Therefore, STAT5 signaling is increased in the liver in GH-transgenic mice during the growth period, with a balance between positive and negative effectors resulting in accelerated but controlled growth.

  11. Overexpression of CTHRC1 in hepatocellular carcinoma promotes tumor invasion and predicts poor prognosis.

    Directory of Open Access Journals (Sweden)

    Yu-Ling Chen

    Full Text Available Collagen triple helix repeat containing-1 (CTHRC1 is a secreted glycoprotein that activates the planar cell polarity pathway of Wnt signaling. Using microarray analysis, we found that the CTHRC1 gene is overexpressed in hepatocellular carcinoma (HCC. The level of CTHRC1 mRNA was measured in 201 surgically resected HCCs using real time reverse transcription-polymerase chain reaction. Overexpression of CTHRC1 in HCC was associated with large tumor size and advanced tumor stage. Furthermore, expression of CTHRC1 as was identified as an independent prognostic factors in the multivariate analysis. Suppression of CTHRC1 expression inhibited tumor migration and invasion whereas overexpression of CTHRC1 promoted tumor invasion. Activation of RhoA, but not Rac1 or Cdc42, was found to play a crucial role in CTHRC1-induced cell migration. CTHRC1 promoted adhesion of cancer cells to extracellular matrix through induction of integrin β1 expression and activation of focal adhesion kinase. These results suggest CTHRC1 promotes tumor invasion and metastasis by enhancing the adhesion and migratory abilities of tumor cells. It is also a promising biomarker for predicting the prognosis of patients with HCC.

  12. 活化的cdc42相关激酶1的高表达影响食管鳞癌的分期和预后%Correlation study of the overexpression of activated Cdc42-associated kinase 1 and the stage and prognosis of esophageal squamous cell carcinoma

    Institute of Scientific and Technical Information of China (English)

    陈照丽; 昌盛; 李宝重; 周芳; 谭晓刚; 石素胜; 冯晓莉; 赫捷

    2011-01-01

    Objective To investigate the expression and relationship of activated Cdc42-associated kinase 1 ( ACK1 ) and the clinical characteristics of esophageal squamous cell carcinoma (ESCC). Methods The ACK1 expression in ESCC cell lines was detected by Western blot Immunohistochemistry was performed to assay the expression level of ACK1 protein in tumor tissues and adjacent normal epithelium from 105 ESCC patients in tissue microarray and 45 patients in normal tissue slices. Semi-quantitative RT-PCR (reverse transcription-polymerase chain reaction)was performed to determine the expression level of ACK1 mRNA in 45 pairs of ESCC frozen tissues. Results The expression level of ACK1 protein was significantly upregulated in 48. 6% ESCC tissues as compared with the normal adjacent epithelium in tissue microarray. The overexpression of ACK1 was significantly correlated with the lymph node metastasis and TNM stage of ESCC patients. The results of normal tissue slices were consistent with those of tissue microarray. Furthermore the overexpression of ACK1 was associated with a poor survival of ESCC patients ( P = 0. 030 ). The elevated mRNA level of ACK1 in ESCC tissues was correlated with the lymph node metastasis and TNM stage of ESCC patients. And a significant correlation was observed between protein and mRNA level of ACK1 (P =0.021 ).Conclusion The up-regulated expressions of ACK1 protein and mRNA are correlated with the progression and prognosis of ESCC.%目的 研究活化的Cdc42相关激酶1(ACK1)在食管鳞癌组织中的表达水平及其临床意义.方法 回顾性收集1990至2001年间在中国医学科学院肿瘤医院接受手术治疗的原发食管癌病例120例,可分析病例为105例.Western印迹检测食管鳞癌细胞中ACK1的表达.免疫组织化学检测了组织芯片中105例和普通病理切片中45例食管鳞癌及其配对的癌旁正常食管黏膜中ACK1蛋白表达水平.半定量RT-PCR检测了45对冰冻食管鳞癌组织中ACK1

  13. Overexpression and export of Vibrio anguillarum metalloprotease in Escherichia coli

    Institute of Scientific and Technical Information of China (English)

    Zhang Fengli; Chi Zhenming; Chen Jixiang; Wu Longfei; Liang Likun

    2007-01-01

    Vibrio anguillarum metalloprotease, an extracellular zinc metalloprotease involved in the virulence mechanism of Vibrio anguillarum, is synthesized from the empA gene as a 611-residue precursor and naturally secreted via Sec secretion pathway in Vibrio anguillarum. In this study, heterologous expression of the empA gene encoding metallopmtease and export of the recombinant metalloprotease in Escherichia coliwere examined. The empA gene was subcloned into pBAD24 with arabinose promoter and sequenced. The sequence encoded a polypeptide(611 amino acids)consisting of four domains: a signal peptide, an Nterminal propeptide, a mature region and a C-terminal propeptide. The empA gene inserted in plasmid pBAD24 was overexpressed in TOP10 strain of E. Coli after arabinose induction. The 36kDa polypeptide of the recombinant metalloprotease as the mature protease was further confirmed by SDS-PAGE and immunoblotting. It was found that recombinant metalloprotease with the EmpA activity and antigenicity wasexported into the periplasm of Escherichia coli cells via Sec translocation pathway, whereas it was secreted into extracellular environments in V. Anguillarum. The results imply that the expression, export and processing mechanism of the protein in E. Coli are similar to those in V. Anguillarum.

  14. Enhanced migration of tissue inhibitor of metalloproteinase overexpressing hepatoma cells is attributed to gelatinases:Relevance to intracellular signaling pathways

    Institute of Scientific and Technical Information of China (English)

    Elke Roeb; Anja-Katrin Bosserhoff; Sabine Hamacher; Bettina Jansen; Judith Dahmen; Sandra Wagner; Siegfried Matern

    2005-01-01

    AIM: To study the effect of gelatinases (especially MMP-9)on migration of tissue inhibitor of metalloproteinase (TIMP-1) overexpressing hepatoma cells.METHODS: Wild type HepG2 cells, cells stably transfected with TIMP-1 and TIMP-1 antagonist (MMP-9-H401A, a catalytically inactive matrix metalloproteinase (MMP) which still binds and neutralizes TIMP-1) were incubated in Boyden chambers either with or without Galardin (a synthetic inhibitor of MMP-1, -2, -3, -8, -9) or a specific inhibitor of gelatinases.RESULTS: Compared to wild type HepG2 cells, the cells overexpressing TIMP-1 showed 115% migration (P<0.05)and the cells overexpressing MMP-9-H401A showed 62% migration (P<0.01). Galardin reduced cell migration dose dependently in all cases. The gelatinase inhibitor reduced migration in TIMP-1 overexpressing cells predominantly.Furthermore, we examined intracellular signal transduction pathways of TIMP-1-dependent HepG2 cells. TIMP-1deactivates cell signaling pathways of MMP-2 and MMP-9involving p38 mitogen-activated protein kinase. Specific blockade of the ERK pathway suppresses gelatinase expression either in the presence or absence of TIMP-1.CONCLUSION: Overexpressing functional TIMP-1-enhanced migration of HepG2-TIMP-1 cells depends on enhanced MMP-activity, especially MMP-9.

  15. Overexpression of LRIG1 regulates PTEN via MAPK/MEK signaling pathway in esophageal squamous cell carcinoma

    Science.gov (United States)

    Jiang, Xiaofang; Li, Huiwu

    2016-01-01

    The present study aimed to evaluate the role of leucine-rich repeats and immunoglobulin-like domain protein 1 (LRIG1) in the regulation of phosphatase and tensin homolog (PTEN) expression in esophageal carcinogenesis. LRIG1 was overexpressed in esophageal squamous cell carcinoma (ESCC) cell lines, and the effect of LRIG1 overexpression on the mRNA and protein expression levels of PTEN was evaluated by reverse transcription-quantitative polymerase chain reaction and western blotting. Furthermore, the effects of LRIG1 overexpression on the cell cycle distribution and apoptosis of ESCC cells were examined by flow cytometry. Various cell signaling pathway inhibitors were used to assess the effects of LRIG1 on downstream signaling in ESCC cell lines. In addition, the association between LRIG1 and PTEN expression was examined in 48 samples from patients with ESCC. LRIG1 overexpression was demonstrated to downregulate PTEN expression in ESCC cell lines, and promote their proliferation and inhibit apoptosis. In addition, LRIG1-mediated suppression of PTEN expression was inhibited by the U0126 inhibitor, which suggests that LRIG1 may inhibit the activation of PTEN signaling molecules by triggering the mitogen-activated protein kinase (MAPK)/MAPK kinase 1 (MEK) signaling pathway. In conclusion, the present study demonstrated that overexpression of LRIG1 significantly and adversely affected the survival of ESCC cells, and that the MAPK/MEK signaling pathway may be responsible for the repression of PTEN expression and function. PMID:27698691

  16. The construction and expression of chimeric urokinase-type plasminogen activator genes containing kringle domains of human plasminogen.

    Science.gov (United States)

    Boutaud, A; Castellino, F J

    1993-06-01

    A series of chimeric urokinase-type plasminogen activator (uPA) genes, which contain combinations of kringle domains of human plasminogen (HPg) in place of the uPA kringle (KuPA), has been constructed and expressed. Some of the resulting recombinant (r) variant uPA chimeras contain modules that potentially mediate the macroscopic binding of HPg to its activation effectors, fibrin(ogen) and 6-aminohexanoic acid (EACA). Such binding sites are not possessed by KuPA, but are present in certain of the HPg kringles, viz., kringle 1 (K1HPg), kringle 4 (K4HPg), and kringle 5 (K5HPg). The recombinant (r) chimeras constructed included molecules with replacements of KuPA with K1HPg (r-[KuPA-->K1HPg]uPA), and with KuPA replaced by double kringle combinations of K1HPgK4HPg (r-[KuPA-->K1HPgK4HPg]uPA), K2HPgK3HPg (r-[KuPA-->K2HPgK3HPg]uPA), and K4HPgK5HPg (r-[KuPA-->K4HPgK5HPg]uPA). All of these variant genes, along with their wild-type (wt) r-uPA counterparts, were expressed in human kidney 293 cells. In cases wherein EACA-binding kringles from HPg have been placed in uPA, this property has been retained in the chimeric molecule and employed as an essential part of the purification procedures for the variants. The steady state amidolytic activity of two-chain (tc) wtr-uPA toward the chromogenic substrate, H-D-pyroglutamyl-Gly-L-Arg-p-nitroanilide (S2444), is characterized by a kcat/KM (pH 7.4, 37 degrees C) of 120 s-1 mM-1. This value ranges from 92 s-1 mM-1 (tcr-[KuPA-->K1HPg]uPA) to 166 s-1 mM-1 (tcr-[KuPA-->K1HPgK4HPg]uPA) for each of the variants, demonstrating that the catalytic efficiency of the active site is altered only in a small way by changes in the noncatalytic domain of uPA. Small differences are also observed in the abilities of these tcr variants to interact with the fast-acting plasma inhibitor of uPA, viz., plasminogen activator inhibitor-1 (PAI-1). The second-order rate constant for the interaction of PAI-1 with tcr-uPA, 0.46 x 10(7) M-1s-1 (pH 7.4, 10 degrees

  17. Cooperatively transcriptional and epigenetic regulation of sonic hedgehog overexpression drives malignant potential of breast cancer.

    Science.gov (United States)

    Duan, Zhao-Heng; Wang, Hao-Chuan; Zhao, Dong-Mei; Ji, Xiao-Xin; Song, Min; Yang, Xiao-Jun; Cui, Wei

    2015-08-01

    Sonic hedgehog (Shh), a ligand of Hedgehog signaling pathway, is considered an important oncogene and an exciting potential therapeutic target in several cancers. Comprehensive understanding of the regulation mechanism of Shh in cancer cells is necessary to find an effective approach to selectively block its tumorigenic function. We and others previously demonstrated that nuclear factor-kappa B (NF-κB) activation and promoter hypomethylation contributed to the overexpression of Shh. However, the relationship between transcriptional and epigenetic regulation of Shh, and their roles in the malignant phenotype of cancer cells are still not clearly elucidated. In the present study, our data showed that the level of Shh was higher in breast cancer tissues with positive NF-κB nuclear staining and promoter hypomethylation. In addition, survival analysis revealed that Shh overexpression, but not hypomethylation and NF-κB nuclear staining, was a poor prognosis indicator for breast cancers. Moreover, in vitro data demonstrated that both NF-κB activation and hypomethylation in promoter region were positively associated with the overexpression of Shh. Mechanistically, the hypomethylation in Shh promoter could facilitate NF-κB binding to its site, and subsequently cooperate to induce transcription of Shh. Furthermore, the biological function data indicated that overexpressed Shh enhanced the self-renewal capacity and migration ability of breast cancer cells, which could be augmented by promoter demethylation and NF-κB activation. Overall, our findings reveal multiple and cooperative mechanisms of Shh upregulation in cancer cells, and the roles of Shh in tumor malignant behavior, thus suggesting a new strategy for therapeutic interventions to reduce Shh in tumors and improve patients' prognosis.

  18. The cooperation between hMena overexpression and HER2 signalling in breast cancer.

    Science.gov (United States)

    Di Modugno, Francesca; Mottolese, Marcella; DeMonte, Lucia; Trono, Paola; Balsamo, Michele; Conidi, Andrea; Melucci, Elisa; Terrenato, Irene; Belleudi, Francesca; Torrisi, Maria Rosaria; Alessio, Massimo; Santoni, Angela; Nisticò, Paola

    2010-12-30

    hMena and the epithelial specific isoform hMena(11a) are actin cytoskeleton regulatory proteins belonging to the Ena/VASP family. EGF treatment of breast cancer cell lines upregulates hMena/hMena(11a) expression and phosphorylates hMena(11a), suggesting cross-talk between the ErbB receptor family and hMena/hMena(11a) in breast cancer. The aim of this study was to determine whether the hMena/hMena(11a) overexpression cooperates with HER-2 signalling, thereby affecting the HER2 mitogenic activity in breast cancer. In a cohort of breast cancer tissue samples a significant correlation among hMena, HER2 overexpression, the proliferation index (high Ki67), and phosphorylated MAPK and AKT was found and among the molecular subtypes the highest frequency of hMena overexpressing tumors was found in the HER2 subtype. From a clinical viewpoint, concomitant overexpression of HER2 and hMena identifies a subgroup of breast cancer patients showing the worst prognosis, indicating that hMena overexpression adds prognostic information to HER2 overexpressing tumors. To identify a functional link between HER2 and hMena, we show here that HER2 transfection in MCF7 cells increased hMena/hMena(11a) expression and hMena(11a) phosphorylation. On the other hand, hMena/hMena(11a) knock-down reduced HER3, AKT and p44/42 MAPK phosphorylation and inhibited the EGF and NRG1-dependent HER2 phosphorylation and cell proliferation. Of functional significance, hMena/hMena(11a) knock-down reduced the mitogenic activity of EGF and NRG1. Collectively these data provide new insights into the relevance of hMena and hMena(11a) as downstream effectors of the ErbB receptor family which may represent a novel prognostic indicator in breast cancer progression, helping to stratify patients.

  19. The cooperation between hMena overexpression and HER2 signalling in breast cancer.

    Directory of Open Access Journals (Sweden)

    Francesca Di Modugno

    Full Text Available hMena and the epithelial specific isoform hMena(11a are actin cytoskeleton regulatory proteins belonging to the Ena/VASP family. EGF treatment of breast cancer cell lines upregulates hMena/hMena(11a expression and phosphorylates hMena(11a, suggesting cross-talk between the ErbB receptor family and hMena/hMena(11a in breast cancer. The aim of this study was to determine whether the hMena/hMena(11a overexpression cooperates with HER-2 signalling, thereby affecting the HER2 mitogenic activity in breast cancer. In a cohort of breast cancer tissue samples a significant correlation among hMena, HER2 overexpression, the proliferation index (high Ki67, and phosphorylated MAPK and AKT was found and among the molecular subtypes the highest frequency of hMena overexpressing tumors was found in the HER2 subtype. From a clinical viewpoint, concomitant overexpression of HER2 and hMena identifies a subgroup of breast cancer patients showing the worst prognosis, indicating that hMena overexpression adds prognostic information to HER2 overexpressing tumors. To identify a functional link between HER2 and hMena, we show here that HER2 transfection in MCF7 cells increased hMena/hMena(11a expression and hMena(11a phosphorylation. On the other hand, hMena/hMena(11a knock-down reduced HER3, AKT and p44/42 MAPK phosphorylation and inhibited the EGF and NRG1-dependent HER2 phosphorylation and cell proliferation. Of functional significance, hMena/hMena(11a knock-down reduced the mitogenic activity of EGF and NRG1. Collectively these data provide new insights into the relevance of hMena and hMena(11a as downstream effectors of the ErbB receptor family which may represent a novel prognostic indicator in breast cancer progression, helping to stratify patients.

  20. Identification of a novel subgroup of melanomas with KIT/cyclin-dependent kinase-4 overexpression.

    Science.gov (United States)

    Smalley, Keiran S M; Contractor, Rooha; Nguyen, Thiennga K; Xiao, Min; Edwards, Robin; Muthusamy, Viswanathan; King, Alastair J; Flaherty, Keith T; Bosenberg, Marcus; Herlyn, Meenhard; Nathanson, Katherine L

    2008-07-15

    Although many melanomas harbor either activating mutations in BRAF or NRAS, there remains a substantial, yet little known, group of tumors without either mutation. Here, we used a genomic strategy to define a novel group of melanoma cell lines with co-overexpression of cyclin-dependent kinase 4 (CDK4) and KIT. Although this subgroup lacked any known KIT mutations, they had high phospho-KIT receptor expression, indicating receptor activity. Quantitative PCR confirmed the existence of a similar KIT/CDK4 subgroup in human melanoma samples. Pharmacologic studies showed the KIT/CDK4-overexpressing subgroup to be resistant to BRAF inhibitors but sensitive to imatinib in both in vitro and in vivo melanoma models. Mechanistically, imatinib treatment led to increased apoptosis and G(1) phase cell cycle arrest associated with the inhibition of phospho-ERK and increased expression of p27(KIP). Other melanoma cell lines, which retained some KIT expression but lacked phospho-KIT, were not sensitive to imatinib, suggesting that KIT expression alone is not predictive of response. We suggest that co-overexpression of KIT/CDK4 is a potential mechanism of oncogenic transformation in some BRAF/NRAS wild-type melanomas. This group of melanomas may be a subpopulation for which imatinib or other KIT inhibitors may constitute optimal therapy.

  1. Cardiomyocyte Overexpression of FABP4 Aggravates Pressure Overload-Induced Heart Hypertrophy.

    Directory of Open Access Journals (Sweden)

    Ji Zhang

    Full Text Available Fatty acid binding protein 4 (FABP4 is a member of the intracellular lipid-binding protein family, responsible for the transportation of fatty acids. It is considered to express mainly in adipose tissues, and be strongly associated with inflammation, obesity, diabetes and cardiovasculardiseases. Here we report that FABP4 is also expressed in cardiomyocytes and plays an important role in regulating heart function under pressure overload. We generated heart-specific transgenic FABP4 (FABP4-TG mice using α myosin-heavy chain (α-MHC promoter and human FABP4 sequence, resulting in over-expression of FABP4 in cardiomyocytes. The FABP4-TG mice displayed normal cardiac morphology and contractile function. When they were subjected to the transverse aorta constriction (TAC procedure, the FABP4-TG mice developed more cardiac hypertrophy correlated with significantly increased ERK phosphorylation, compared with wild type controls. FABP4 over-expression in cardiomyocytes activated phosphor-ERK signal and up-regulate the expression of cardiac hypertrophic marker genes. Conversely, FABP4 induced phosphor-ERK signal and hypertrophic gene expressions can be markedly inhibited by an ERK inhibitor PD098059 as well as the FABP4 inhibitor BMS309403. These results suggest that FABP4 over-expression in cardiomyocytes can aggravate the development of cardiac hypertrophy through the activation of ERK signal pathway.

  2. Overexpression of the protein tyrosine phosphatase PRL-2 correlates with breast tumor formation and progression.

    Science.gov (United States)

    Hardy, Serge; Wong, Nau Nau; Muller, William J; Park, Morag; Tremblay, Michel L

    2010-11-01

    The PRL-1, PRL-2, and PRL-3 phosphatases are prenylated protein tyrosine phosphatases with oncogenic activity that are proposed to drive tumor metastasis. We found that PRL-2 mRNA is elevated in primary breast tumors relative to matched normal tissue, and also dramatically elevated in metastatic lymph nodes compared with primary tumors. PRL-2 knockdown in metastatic MDA-MB-231 breast cancer cells decreased anchorage-independent growth and cell migration, suggesting that the malignant phenotype of these cells is mediated at least in part through PRL-2 signaling. In different mouse mammary tumor-derived cell lines overexpressing PRL-2, we confirmed its role in anchorage-independent growth and cell migration. Furthermore, injection of PRL-2-overexpressing cells into the mouse mammary fat pad promoted extracellular signal-regulated kinase 1/2 activation and tumor formation. MMTV-PRL-2 transgenic mice engineered to overexpress the enzyme in mammary tissue did not exhibit spontaneous tumorigenesis, but they exhibited an accelerated development of mammary tumors initiated by introduction of an MMTV-ErbB2 transgene. Together, our results argue that PRL-2 plays a role in breast cancer progression.

  3. Acute overexpression of lactate dehydrogenase-A perturbs beta-cell mitochondrial metabolism and insulin secretion.

    Science.gov (United States)

    Ainscow, E K; Zhao, C; Rutter, G A

    2000-07-01

    Islet beta-cells express low levels of lactate dehydrogenase and have high glycerol phosphate dehydrogenase activity. To determine whether this configuration favors oxidative glucose metabolism via mitochondria in the beta-cell and is important for beta-cell metabolic signal transduction, we have determined the effects on glucose metabolism and insulin secretion of acute overexpression of the skeletal muscle isoform of lactate dehydrogenase (LDH)-A. Monitored in single MIN6 beta-cells, LDH hyperexpression (achieved by intranuclear cDNA microinjection or adenoviral infection) diminished the response to glucose of both phases of increases in mitochondrial NAD(P)H, as well as increases in mitochondrial membrane potential, cytosolic free ATP, and cystolic free Ca2+. These effects were observed at all glucose concentrations, but were most pronounced at submaximal glucose levels. Correspondingly, adenoviral vector-mediated LDH-A overexpression reduced insulin secretion stimulated by 11 mmol/l glucose and the subsequent response to stimulation with 30 mmol/l glucose, but it was without significant effect when the concentration of glucose was raised acutely from 3 to 30 mmol/l. Thus, overexpression of LDH activity interferes with normal glucose metabolism and insulin secretion in the islet beta-cell type, and it may therefore be directly responsible for insulin secretory defects in some forms of type 2 diabetes. The results also reinforce the view that glucose-derived pyruvate metabolism in the mitochondrion is critical for glucose-stimulated insulin secretion in the beta-cell.

  4. Overexpression of Rac1 in leukemia patients and its role in leukemia cell migration and growth

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jiying [State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, 288 Nanjing Road, Tianjin 300020 (China); Rao, Qing, E-mail: raoqing@gmail.com [State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, 288 Nanjing Road, Tianjin 300020 (China); Wang, Min; Wei, Hui; Xing, Haiyan; Liu, Hang; Wang, Yanzhong; Tang, Kejing; Peng, Leiwen; Tian, Zheng; Wang, Jianxiang [State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, 288 Nanjing Road, Tianjin 300020 (China)

    2009-09-04

    Rac1 belongs to the Rho family that act as critical mediators of signaling pathways controlling cell migration and proliferation and contributes to the interactions of hematopoietic stem cells with their microenvironment. Alteration of Rac1 might result in unbalanced interactions and ultimately lead to leukemogenesis. In this study, we analyze the expression of Rac1 protein in leukemia patients and determine its role in the abnormal behaviours of leukemic cells. Rac1 protein is overexpressed in primary acute myeloid leukemia cells as compared to normal bone marrow mononuclear cells. siRNA-mediated silencing of Rac1 in leukemia cell lines induced inhibition of cell migration, proliferation, and colony formation. Additionally, blocking Rac1 activity by an inhibitor of Rac1-GTPase, NSC23766, suppressed cell migration and growth. We conclude that overexpression of Rac1 contributes to the accelerated migration and high proliferation potential of leukemia cells, which could be implicated in leukemia development and progression.

  5. Analysis of Rheb in the cellular slime mold Dictyostelium discoideum: Cellular localization, spatial expression and overexpression

    Indian Academy of Sciences (India)

    Pynskhem Bok Swer; Pooja Bhadoriya; Shweta Saran

    2014-03-01

    Dictyostelium discoideum encodes a single Rheb protein showing sequence similarity to human homologues of Rheb. The DdRheb protein shares 52% identity and 100% similarity with the human Rheb1 protein. Fluorescence of Rheb yellow fluorescent protein fusion was detected in the D. discoideum cytoplasm. Reverse transcription-polymerase chain reaction and whole-mount in situ hybridization analyses showed that rheb is expressed at all stages of development and in prestalk cells in the multicellular structures developed. When the expression of rheb as a fusion with lacZ was driven under its own promoter, the -galactosidase activity was seen in the prestalk cells. D. discoideum overexpressing Rheb shows an increase in the size of the cell. Treatment of the overexpressing Rheb cells with rapamycin confirms its involvement in the TOR signalling pathway.

  6. Glycomic and sialoproteomic data of gastric carcinoma cells overexpressing ST3GAL4.

    Science.gov (United States)

    Mereiter, Stefan; Magalhães, Ana; Adamczyk, Barbara; Jin, Chunsheng; Almeida, Andreia; Drici, Lylia; Ibáñez-Vea, Maria; Larsen, Martin R; Kolarich, Daniel; Karlsson, Niclas G; Reis, Celso A

    2016-06-01

    Gastric carcinoma MKN45 cells stably transfected with the full-length ST3GAL4 gene were characterised by glycomic and sialoproteomic analysis. Complementary strategies were applied to assess the glycomic alterations induced by ST3GAL4 overexpression. The N- and O-glycome data were generated in two parallel structural analyzes, based on PGC-ESI-MS/MS. Data on glycan structure identification and relative abundance in ST3GAL4 overexpressing cells and respective mock control are presented. The sialoproteomic analysis based on titanium-dioxide enrichment of sialopeptides with subsequent LC-MS/MS identification was performed. This analysis identified 47 proteins with significantly increased sialylation. The data in this article is associated with the research article published in Biochim Biophys Acta "Glycomic analysis of gastric carcinoma cells discloses glycans as modulators of RON receptor tyrosine kinase activation in cancer" [1].

  7. Overexpression of Annexin II Receptor-Induced Autophagy Protects Against Apoptosis in Uveal Melanoma Cells.

    Science.gov (United States)

    Zhang, Yuelu; Song, Hongyuan; Guo, Ting; Zhu, Yongzhe; Tang, Hailin; Qi, Zhongtian; Zhao, Ping; Zhao, Shihong

    2016-05-01

    Uveal melanoma is the most common primary malignant intraocular tumor in adults and still lacks effective systemic therapies. Annexin A2 receptor (AXIIR), a receptor for Annexin II, was demonstrated to play an important role in multiple cells, but its role in uveal melanoma cells remains exclusive. Herein, the authors reported that overexpression of AXIIR was able to reduce cell viability and activate apoptosis apparently in the Mum2C uveal melanoma cell line. Meanwhile, overexpression of AXIIR could induce autophagy and increase autophagy flux. After autophagy was inhibited by chloroquine, enhanced apoptosis and cytotoxicity could be detected. In summary, these data highlighted the crucial role of AXIIR in reducing Mum2C cell viability through inducing apoptosis, while autophagy played a protective role in this process. Interference of this gene may be a promising method for uveal melanoma therapy and combination with specific inhibitor of autophagy may serve as a supplementary.

  8. Mannose 6-Phosphate Receptor Is Reduced in -Synuclein Overexpressing Models of Parkinsons Disease

    DEFF Research Database (Denmark)

    Matrone, Carmela; Dzamko, Nicolas; Madsen, Peder;

    2016-01-01

    Increasing evidence points to defects in autophagy as a common denominator in most neurodegenerative conditions. Progressive functional decline in the autophagy-lysosomal pathway (ALP) occurs with age, and the consequent impairment in protein processing capacity has been associated with a higher...... to autophagy defects in PD neurons is still uncertain. Here we demonstrate that MPR300 shuttling between endosomes and the trans Golgi network is altered in α-synuclein overexpressing neurons. Consequently, CD is not correctly trafficked to lysosomes and cannot be processed to generate its mature active form......, leading to a reduced CD-mediated α-synuclein degradation and α-synuclein accumulation in neurons. MPR300 is downregulated in brain from α-synuclein overexpressing animal models and in PD patients with early diagnosis. These data indicate MPR300 as crucial player in the autophagy-lysosomal dysfunctions...

  9. Glycomic and sialoproteomic data of gastric carcinoma cells overexpressing ST3GAL4

    Directory of Open Access Journals (Sweden)

    Stefan Mereiter

    2016-06-01

    Full Text Available Gastric carcinoma MKN45 cells stably transfected with the full-length ST3GAL4 gene were characterised by glycomic and sialoproteomic analysis. Complementary strategies were applied to assess the glycomic alterations induced by ST3GAL4 overexpression. The N- and O-glycome data were generated in two parallel structural analyzes, based on PGC-ESI-MS/MS. Data on glycan structure identification and relative abundance in ST3GAL4 overexpressing cells and respective mock control are presented. The sialoproteomic analysis based on titanium-dioxide enrichment of sialopeptides with subsequent LC-MS/MS identification was performed. This analysis identified 47 proteins with significantly increased sialylation. The data in this article is associated with the research article published in Biochim Biophys Acta “Glycomic analysis of gastric carcinoma cells discloses glycans as modulators of RON receptor tyrosine kinase activation in cancer” [1].

  10. Over-expression of ST3Gal-I promotes mammary tumorigenesis

    DEFF Research Database (Denmark)

    Picco, Gianfranco; Julien, Sylvain; Brockhausen, Inka;

    2010-01-01

    3Gal-I adds sialic acid to the galactose residue of core 1 (Galbeta1,3GalNAc) O-glycans and this enzyme is over-expressed in breast cancer resulting in the expression of sialylated core 1 glycans. In order to study the role of ST3Gal-I in mammary tumor development, we developed transgenic mice......Changes in glycosylation are common in malignancy, and as almost all surface proteins are glycosylated, this can dramatically affect the behavior of tumor cells. In breast carcinomas, the O-linked glycans are frequently truncated, often as a result of premature sialylation. The sialyltransferase ST...... that over-express the sialyltransferase under the control of the human membrane-bound mucin 1 promoter. These mice were then crossed with PyMT mice that spontaneously develop mammary tumors. As expected, ST3Gal-I transgenic mice showed increased activity and expression of the enzyme in the pregnant...

  11. Overexpression of Bax sensitizes prostate cancer cells to TGF-β induced apoptosis

    Institute of Scientific and Technical Information of China (English)

    Pei Hui LIN; Zui PAN; Lin ZHENG; Na LI; David DANIELPOUR; Jian Jie MA

    2005-01-01

    NRP-154 is a tumorigenic epithelial cell line derived from the preneoplastic dorsal-lateral prostate of rats. These cells are exquisitely sensitive to TGF-β induced apoptosis. In contrast, we find that NRP-154 cells can sustain overexpression of exogenous Bax protein, which is different from non-tumor cells where Bax functions as a ubiquitous stimulator of apoptosis. NRP-154 cells stably overexpressing Bax show increased sensitivity to TGF-β induced apoptosis. The degree of TGF-β induced apoptosis displays high correlation with cleavage of Bax at the amino-terminus. Our data indicate that prostate cancer cells can host high levels of latent Bax which can be activated through post-translational modification.

  12. [Overexpression of Penicillium expansum lipase gene in Pichia pastoris].

    Science.gov (United States)

    Yuan, Cai; Lin, Lin; Shi, Qiao-Qin; Wu, Song-Gang

    2003-03-01

    The alkaline lipase gene of Penicillium expansum (PEL) was coloned into the yeast integrative plasmid pPIC3.5K, which was then transformed into His4 mutant yeast GS115. Recombinant Pichia strains were obtained by minimal olive oil-methanol plates screening and confirmed by PCR. The expression producus of PEL gene was analysis by SDS-PAGE and olive oil plate, the result indicated that PEL gene was functionally overexpressed in Pichia pastoris and up to 95% of the secreted protein. Recombinant lipase had a molecular mass of 28kD, showing a range similar to that of PEL, could hydrolyze olive oil and formed clear halos in the olive oil plates. Four different strategies (different media, pH, glycerol and methanol concentration) were applied to optimize the cultivation conditions, the activity of lipase was up to 260 u/mL under the optimal cultivation conditions. It is pointed out that the absence of the expensive biotin and yeast nitrogen base in the medium increased the lipase production. The possible reason of this result is absence of yeast nitrogen base increased the medium pH during cultivation, and PEL shows a higher stability at this condition. The lipase activity of the supernatant from the culture grown at pH 7 was higher than the one from the culture in the same medium at pH 6.0 is due to the pH stability of PEL too. The results also showed that the methanol and glycerol concentration had a marked effect on the production of lipase.

  13. Anosmin-1 over-expression regulates oligodendrocyte precursor cell proliferation, migration and myelin sheath thickness.

    Science.gov (United States)

    Murcia-Belmonte, Verónica; Esteban, Pedro F; Martínez-Hernández, José; Gruart, Agnès; Luján, Rafael; Delgado-García, José María; de Castro, Fernando

    2016-04-01

    During development of the central nervous system, anosmin-1 (A1) works as a chemotropic cue contributing to axonal outgrowth and collateralization, as well as modulating the migration of different cell types, fibroblast growth factor receptor 1 (FGFR1) being the main receptor involved in all these events. To further understand the role of A1 during development, we have analysed the over-expression of human A1 in a transgenic mouse line. Compared with control mice during development and in early adulthood, A1 over-expressing transgenic mice showed an enhanced oligodendrocyte precursor cell (OPC) proliferation and a higher number of OPCs in the subventricular zone and in the corpus callosum (CC). The migratory capacity of OPCs from the transgenic mice is increased in vitro due to a higher basal activation of ERK1/2 mediated through FGFR1 and they also produced more myelin basic protein (MBP). In vivo, the over-expression of A1 resulted in an elevated number of mature oligodendrocytes with higher levels of MBP mRNA and protein, as well as increased levels of activation of the ERK1/2 proteins, while electron microscopy revealed thicker myelin sheaths around the axons of the CC in adulthood. Also in the mature CC, the nodes of Ranvier were significantly longer and the conduction velocity of the nerve impulse in vivo was significantly increased in the CC of A1 over-expressing transgenic mice. Altogether, these data confirmed the involvement of A1 in oligodendrogliogenesis and its relevance for myelination.

  14. Overexpression of the mitochondrial T3 receptor induces skeletal muscle atrophy during aging.

    Directory of Open Access Journals (Sweden)

    François Casas

    Full Text Available In previous studies, we characterized a new hormonal pathway involving a mitochondrial T3 receptor (p43 acting as a mitochondrial transcription factor. In in vitro and in vivo studies, we have shown that p43 increases mitochondrial transcription and mitochondrial biogenesis. In addition, p43 overexpression in skeletal muscle stimulates mitochondrial respiration and induces a shift in metabolic and contractile features of muscle fibers which became more oxidative.Here we have studied the influence of p43 overexpression in skeletal muscle of mice during aging. We report that p43 overexpression initially increased mitochondrial mass. However, after the early rise in mitochondrial DNA occurring at 2 months of age in transgenic mice, we observed a progressive decrease of mitochondrial DNA content which became 2-fold lower at 23 months of age relatively to control animals. Moreover, p43 overexpression induced an oxidative stress characterized by a strong increase of lipid peroxidation and protein oxidation in quadriceps muscle, although antioxidant enzyme activities (catalase and superoxide dismutase were stimulated. In addition, muscle atrophy became detectable at 6 months of age, probably through a stimulation of the ubiquitin proteasome pathway via two muscle-specific ubiquitin ligases E3, Atrogin-1/MAFbx and MuRF1.Taken together, these results demonstrate that a prolonged stimulation of mitochondrial activity induces muscle atrophy. In addition, these data underline the importance of a tight control of p43 expression and suggest that a deregulation of the direct T3 mitochondrial pathway could be one of the parameters involved in the occurrence of sarcopenia.

  15. Identification of cytotoxic drugs that selectively target tumor cells with MYC overexpression.

    Directory of Open Access Journals (Sweden)

    Anna Frenzel

    Full Text Available Expression of MYC is deregulated in a wide range of human cancers, and is often associated with aggressive disease and poorly differentiated tumor cells. Identification of compounds with selectivity for cells overexpressing MYC would hence be beneficial for the treatment of these tumors. For this purpose we used cell lines with conditional MYCN or c-MYC expression, to screen a library of 80 conventional cytotoxic compounds for their ability to reduce tumor cell viability and/or growth in a MYC dependent way. We found that 25% of the studied compounds induced apoptosis and/or inhibited proliferation in a MYC-specific manner. The activities of the majority of these were enhanced both by c-MYC or MYCN over-expression. Interestingly, these compounds were acting on distinct cellular targets, including microtubules (paclitaxel, podophyllotoxin, vinblastine and topoisomerases (10-hydroxycamptothecin, camptothecin, daunorubicin, doxorubicin, etoposide as well as DNA, RNA and protein synthesis and turnover (anisomycin, aphidicholin, gliotoxin, MG132, methotrexate, mitomycin C. Our data indicate that MYC overexpression sensitizes cells to disruption of specific pathways and that in most cases c-MYC and MYCN overexpression have similar effects on the responses to cytotoxic compounds. Treatment of the cells with topoisomerase I inhibitors led to down-regulation of MYC protein levels, while doxorubicin and the small molecule MYRA-A was found to disrupt MYC-Max interaction. We conclude that the MYC pathway is only targeted by a subset of conventional cytotoxic drugs currently used in the clinic. Elucidating the mechanisms underlying their specificity towards MYC may be of importance for optimizing treatment of tumors with MYC deregulation. Our data also underscores that MYC is an attractive target for novel therapies and that cellular screenings of chemical libraries can be a powerful tool for identifying compounds with a desired biological activity.

  16. Identification of cytotoxic drugs that selectively target tumor cells with MYC overexpression.

    Science.gov (United States)

    Frenzel, Anna; Zirath, Hanna; Vita, Marina; Albihn, Ami; Henriksson, Marie Arsenian

    2011-01-01

    Expression of MYC is deregulated in a wide range of human cancers, and is often associated with aggressive disease and poorly differentiated tumor cells. Identification of compounds with selectivity for cells overexpressing MYC would hence be beneficial for the treatment of these tumors. For this purpose we used cell lines with conditional MYCN or c-MYC expression, to screen a library of 80 conventional cytotoxic compounds for their ability to reduce tumor cell viability and/or growth in a MYC dependent way. We found that 25% of the studied compounds induced apoptosis and/or inhibited proliferation in a MYC-specific manner. The activities of the majority of these were enhanced both by c-MYC or MYCN over-expression. Interestingly, these compounds were acting on distinct cellular targets, including microtubules (paclitaxel, podophyllotoxin, vinblastine) and topoisomerases (10-hydroxycamptothecin, camptothecin, daunorubicin, doxorubicin, etoposide) as well as DNA, RNA and protein synthesis and turnover (anisomycin, aphidicholin, gliotoxin, MG132, methotrexate, mitomycin C). Our data indicate that MYC overexpression sensitizes cells to disruption of specific pathways and that in most cases c-MYC and MYCN overexpression have similar effects on the responses to cytotoxic compounds. Treatment of the cells with topoisomerase I inhibitors led to down-regulation of MYC protein levels, while doxorubicin and the small molecule MYRA-A was found to disrupt MYC-Max interaction. We conclude that the MYC pathway is only targeted by a subset of conventional cytotoxic drugs currently used in the clinic. Elucidating the mechanisms underlying their specificity towards MYC may be of importance for optimizing treatment of tumors with MYC deregulation. Our data also underscores that MYC is an attractive target for novel therapies and that cellular screenings of chemical libraries can be a powerful tool for identifying compounds with a desired biological activity.

  17. Overexpression of denticleless E3 ubiquitin protein ligase homolog (DTL) is related to poor outcome in gastric carcinoma

    OpenAIRE

    Kobayashi, Hiroki; Komatsu, Shuhei; Ichikawa, Daisuke; Kawaguchi, Tsutomu; Hirajima, Shoji; Miyamae, Mahito; Okajima, Wataru; Ohashi, Takuma; Kosuga, Toshiyuki; Konishi, Hirotaka; Shiozaki, Atsushi; FUJIWARA, Hitoshi; Okamoto, Kazuma; Tsuda, Hitoshi; Otsuji, Eigo

    2015-01-01

    Background Denticleless E3 ubiquitin protein ligase homolog (DTL) has been identified in amplified region (1q32) of several cancers and has an oncogenic function. In this study, we tested whether DTL acts as a cancer-promoting gene through its activation/overexpression in gastric cancer (GC). Methods We analyzed 7 GC cell lines and 100 primary tumors that were curatively resected in our hospital between 2001 and 2003. Results Overexpression of the DTL protein was detected in GC cell lines (4/...

  18. Relaxin Stimulates cAMP Production in MCF-7 Cells upon Overexpression of Type V Adenylyl Cyclase

    OpenAIRE

    Nguyen, Bao T.; Dessauer, Carmen W.

    2005-01-01

    Relaxin stimulates cAMP production and activation of ERK and PI3K in THP-1 cells. Relaxin also stimulates protein kinase C zeta (PKCζ) translocation to the plasma membrane in a PI3K-dependent manner in THP-1 and MCF-7 cells. However, relaxin did not increase cAMP production in MCF-7 cells. We overexpressed different adenylyl cyclase (AC) isoforms in MCF-7 cells to examine coupling of endogenous relaxin receptors to cAMP production. Overexpression of types II and IV AC had no effect on cAMP pr...

  19. mad—overexpression down regulates the malignant growth and p53 mediated apoptosis in human hepatocellular carcinoma BEL—7404 cells

    Institute of Scientific and Technical Information of China (English)

    ZHANHUA; YONGHUAXU

    1999-01-01

    Mad protein has been shown as an antagonist of cMyc protein in some cell lines.The effect of Mad protein to the malignant phenotype of human hepatoma BEL-7404 cell line was investigated experimentally.An eukarryotic vector pCDNA Ⅲ containing full ORF fragment of mad cDNA was transfected into targeted cells.Under G418 selection,stable Mad-overexpressed cells were cloned.Studies on the effect of Mad over-expression in cell proliferation and cell cycle revealed that cell morphology of the Mad-overexpressed BEL-7404-M1 cells was significantly different from the parent and control vector transfected cells.DNA synthesis,cell proliferation and anchorage-independent growth in soft-agar of the madtransfected cells were partially inhibited in comparison to control cells.Flos cytometry analysis indicated that mad over-expression might block more transfectant cells at G0/G1 phase,resulting in the retardation of cell proliferation.RT-PCR detected a marked inhibition of the expression of cdc25A,an important regulator gene of G0/G1 to S phase in cell cycle.It was also found that Mad protein overexpression could greatly suppress p53-mediated apoptosis in BEL-74040M1 cells in the absence of serume.Thus,Mad proteins may function as a negative regulator antagonizing c-Myc activity in the control of cell growth and apoptosis in human hepatocellular carcinoma BEL-7404 cells.

  20. ERK and AKT signaling drive MED1 overexpression in prostate cancer in association with elevated proliferation and tumorigenicity.

    Science.gov (United States)

    Jin, Feng; Irshad, Shazia; Yu, Wei; Belakavadi, Madesh; Chekmareva, Marina; Ittmann, Michael M; Abate-Shen, Cory; Fondell, Joseph D

    2013-07-01

    MED1 is a key coactivator of the androgen receptor (AR) and other signal-activated transcription factors. Whereas MED1 is overexpressed in prostate cancer cell lines and is thought to coactivate distinct target genes involved in cell-cycle progression and castration-resistant growth, the underlying mechanisms by which MED1 becomes overexpressed and its oncogenic role in clinical prostate cancer have remained unclear. Here, we report that MED1 is overexpressed in the epithelium of clinically localized human prostate cancer patients, which correlated with elevated cellular proliferation. In a Nkx3.1:Pten mutant mouse model of prostate cancer that recapitulates the human disease, MED1 protein levels were markedly elevated in the epithelium of both invasive and castration-resistant adenocarcinoma prostate tissues. Mechanistic evidence showed that hyperactivated ERK and/or AKT signaling pathways promoted MED1 overexpression in prostate cancer cells. Notably, ectopic MED1 overexpression in prostate cancer xenografts significantly promoted tumor growth in nude mice. Furthermore, MED1 expression in prostate cancer cells promoted the expression of a number of novel genes involved in inflammation, cell proliferation, and survival. Together, these findings suggest that elevated MED1 is a critical molecular event associated with prostate oncogenesis.

  1. High-level quinolone resistance is associated with the overexpression of smeVWX in Stenotrophomonas maltophilia clinical isolates.

    Science.gov (United States)

    García-León, G; Ruiz de Alegría Puig, C; García de la Fuente, C; Martínez-Martínez, L; Martínez, J L; Sánchez, M B

    2015-05-01

    Stenotrophomonas maltophilia is the only known bacterium in which quinolone-resistant isolates do not present mutations in the genes encoding bacterial topoisomerases. The expression of the intrinsic quinolone resistance elements smeDEF, smeVWX and Smqnr was analysed in 31 clinical S. maltophilia isolates presenting a minimum inhibitory concentration (MIC) range to ciprofloxacin between 0.5 and > 32 μg/mL; 11 (35.5%) overexpressed smeDEF, 2 (6.5%) presenting the highest quinolone MICs overexpressed smeVWX and 1 (3.2%) overexpressed Smqnr. Both strains overexpressing smeVWX presented changes at the Gly266 position of SmeRv, the repressor of smeVWX. Changes at the same position were previously observed in in vitro selected S. maltophilia quinolone-resistant mutants, indicating this amino acid is highly relevant for the activity of SmeRv in repressing smeVWX expression. For the first time SmeVWX overexpression is associated with quinolone resistance of S. maltophilia clinical isolates.

  2. Overexpression of ADH1 and HXT1 genes in the yeast Saccharomyces cerevisiae improves the fermentative efficiency during tequila elaboration.

    Science.gov (United States)

    Gutiérrez-Lomelí, Melesio; Torres-Guzmán, Juan Carlos; González-Hernández, Gloria Angélica; Cira-Chávez, Luis Alberto; Pelayo-Ortiz, Carlos; Ramírez-Córdova, Jose de Jesús

    2008-05-01

    This work assessed the effect of the overexpression of ADH1 and HXT1 genes in the Saccharomyces cerevisiae AR5 strain during fermentation of Agave tequilana Weber blue variety must. Both genes were cloned individually and simultaneously into a yeast centromere plasmid. Two transformant strains overexpressing ADH1 and HXT1 individually and one strain overexpressing both genes were randomly selected and named A1, A3 and A5 respectively. Overexpression effect on growth and ethanol production of the A1, A3 and A5 strains was evaluated in fermentative conditions in A. tequilana Weber blue variety must and YPD medium. During growth in YPD and Agave media, all the recombinant strains showed lower cell mass formation than the wild type AR5 strain. Adh enzymatic activity in the recombinant strains A1 and A5 cultivated in A. tequilana and YPD medium was higher than in the wild type. The overexpression of both genes individually and simultaneously had no significant effect on ethanol formation; however, the fermentative efficiency of the A5 strain increased from 80.33% to 84.57% and 89.40% to 94.29% in YPD and Agave medium respectively.

  3. Ectopic overexpression of the cell wall invertase gene CIN1 leads to dehydration avoidance in tomato.

    Science.gov (United States)

    Albacete, Alfonso; Cantero-Navarro, Elena; Großkinsky, Dominik K; Arias, Cintia L; Balibrea, María Encarnación; Bru, Roque; Fragner, Lena; Ghanem, Michel E; González, María de la Cruz; Hernández, Jose A; Martínez-Andújar, Cristina; van der Graaff, Eric; Weckwerth, Wolfram; Zellnig, Günther; Pérez-Alfocea, Francisco; Roitsch, Thomas

    2015-02-01

    Drought stress conditions modify source-sink relations, thereby influencing plant growth, adaptive responses, and consequently crop yield. Invertases are key metabolic enzymes regulating sink activity through the hydrolytic cleavage of sucrose into hexose monomers, thus playing a crucial role in plant growth and development. However, the physiological role of invertases during adaptation to abiotic stress conditions is not yet fully understood. Here it is shown that plant adaptation to drought stress can be markedly improved in tomato (Solanum lycopersicum L.) by overexpression of the cell wall invertase (cwInv) gene CIN1 from Chenopodium rubrum. CIN1 overexpression limited stomatal conductance under normal watering regimes, leading to reduced water consumption during the drought period, while photosynthetic activity was maintained. This caused a strong increase in water use efficiency (up to 50%), markedly improving water stress adaptation through an efficient physiological strategy of dehydration avoidance. Drought stress strongly reduced cwInv activity and induced its proteinaceous inhibitor in the leaves of the wild-type plants. However, the CIN1-overexpressing plants registered 3- to 6-fold higher cwInv activity in all analysed conditions. Surprisingly, the enhanced invertase activity did not result in increased hexose concentrations due to the activation of the metabolic carbohydrate fluxes, as reflected by the maintenance of the activity of key enzymes of primary metabolism and increased levels of sugar-phosphate intermediates under water deprivation. The induced sink metabolism in the leaves explained the maintenance of photosynthetic activity, delayed senescence, and increased source activity under drought stress. Moreover, CIN1 plants also presented a better control of production of reactive oxygen species and sustained membrane protection. Those metabolic changes conferred by CIN1 overexpression were accompanied by increases in the concentrations of the

  4. Metabolic Engineering of Mannitol Production in Lactococcus lactis: Influence of Overexpression of Mannitol 1-Phosphate Dehydrogenase in Different Genetic Backgrounds

    NARCIS (Netherlands)

    Wisselink, H.W.; Mars, A.E.; Meer, van der P.; Eggink, G.; Hugenholtz, J.

    2004-01-01

    To obtain a mannitol-producing Lactococcus lactis strain, the mannitol 1-phosphate dehydrogenase gene (mtlD) from Lactobacillus plantarum was overexpressed in a wild-type strain, a lactate dehydrogenase(LDH)-deficient strain, and a strain with reduced phosphofructokinase activity. High-performance l

  5. Effects of EpCAM overexpression on human breast cancer cell lines

    Directory of Open Access Journals (Sweden)

    Krobitsch Sylvia

    2011-01-01

    Full Text Available Abstract Background Recently, EpCAM has attracted major interest as a target for antibody- and vaccine-based cancer immunotherapies. In breast cancer, the EpCAM antigen is overexpressed in 30-40% of all cases and this increased expression correlates with poor prognosis. The use of EpCAM-specific monoclonal antibodies is a promising treatment approach in these patients. Methods In order to explore molecular changes following EpCAM overexpression, we investigated changes of the transcriptome upon EpCAM gene expression in commercially available human breast cancer cells lines Hs578T and MDA-MB-231. To assess cell proliferation, a tetrazolium salt based assay was performed. A TCF/LEF Reporter Kit was used to measure the transcriptional activity of the Wnt/β-catenin pathway. To evaluate the accumulation of β-catenin in the nucleus, a subcellular fractionation assay was performed. Results For the first time we could show that expression profiling data of EpCAM transfected cell lines Hs578TEpCAM and MDA-MB-231EpCAM indicate an association of EpCAM overexpression with the downregulation of the Wnt signaling inhibitors SFRP1 and TCF7L2. Confirmation of increased Wnt signaling was provided by a TCF/LEF reporter kit and by the finding of the nuclear accumulation of ß-catenin for MDA-MB-231EpCAM but not Hs578TEpCAM cells. In Hs578T cells, an increase of proliferation and chemosensitivity to Docetaxel was associated with EpCAM overexpression. Conclusions These data show a cell type dependent modification of Wnt signaling components after EpCAM overexpression in breast cancer cell lines, which results in marginal functional changes. Further investigations on the interaction of EpCAM with SFRP1 and TCF7L2 and on additional factors, which may be causal for changes upon EpCAM overexpression, will help to characterize unique molecular properties of EpCAM-positive breast cancer cells.

  6. TOX3 (TNRC9) overexpression in bladder cancer cells decreases cellular proliferation and triggers an interferon-like response

    DEFF Research Database (Denmark)

    Birkenkamp-Demtröder, Karin; Mansilla, Francisco; Andersen, Lars Dyrskjøt

    2013-01-01

    urothelium. Microarray expression profiling of human bladder cancer cells overexpressing TOX3 followed by Pathway analysis showed that TOX3 overexpression mainly affected the Interferon Signaling Pathway. TOX3 upregulation induced the expression of several genes with a gamma interferon activation site (GAS......), e.g. STAT1. In vitro functional studies showed that TOX3 was able to bind to the GAS-sequence located at the STAT1 promoter. siRNA mediated knockdown of TOX3 in RT4 bladder cancer cells decreased STAT1 expression suggesting a direct impact of TOX3 on STAT1. Immunoprecipitation of TOX3 overexpressing......Background Human TOX3 (TOX high mobility group box family member 3) regulates Ca2+-dependent transcription in neurons and has been associated with breast cancer susceptibility. Aim of the study was to investigate the expression of TOX3 in bladder cancer tissue samples and to identify genes...

  7. MUSCLE-SPECIFIC OVEREXPRESSION OF THE CATALYTIC SUBUNIT OF DNA POLYMERASE γ INDUCES PUPAL LETHALITY IN Drosophila melanogaster

    Science.gov (United States)

    Martínez-Azorín, Francisco; Calleja, Manuel; Hernández-Sierra, Rosana; Farr, Carol L.; Kaguni, Laurie S.; Garesse, Rafael

    2015-01-01

    We show the physiological effects and molecular characterization of overexpression of the catalytic core of mitochondrial DNA (mtDNA) polymerase (pol γ-α) in muscle of Drosophila melanogaster. Muscle-specific overexpression of pol γ-α using the UAS/GAL4 (where UAS is upstream activation sequence) system produced more than 90% of lethality at the end of pupal stage at 25°C, and the survivor adult flies showed a significant reduction in life span. The survivor flies displayed a decreased mtDNA level that is accompanied by a corresponding decrease in the levels of the nucleoid-binding protein mitochondrial transcription factor A (mtTFA). Furthermore, an increase in apoptosis is detected in larvae and adults overexpressing pol γ-α. We suggest that the pupal lethality and reduced life span of survivor adult flies are both caused mainly by massive apoptosis of muscle cells induced by mtDNA depletion. PMID:23729397

  8. Targeted overexpression of amelotin disrupts the microstructure of dental enamel.

    Directory of Open Access Journals (Sweden)

    Rodrigo S Lacruz

    Full Text Available We have previously identified amelotin (AMTN as a novel protein expressed predominantly during the late stages of dental enamel formation, but its role during amelogenesis remains to be determined. In this study we generated transgenic mice that produce AMTN under the amelogenin (Amel gene promoter to study the effect of AMTN overexpression on enamel formation in vivo. The specific overexpression of AMTN in secretory stage ameloblasts was confirmed by Western blot and immunohistochemistry. The gross histological appearance of ameloblasts or supporting cellular structures as well as the expression of the enamel proteins amelogenin (AMEL and ameloblastin (AMBN was not altered by AMTN overexpression, suggesting that protein production, processing and secretion occurred normally in transgenic mice. The expression of Odontogenic, Ameloblast-Associated (ODAM was slightly increased in secretory stage ameloblasts of transgenic animals. The enamel in AMTN-overexpressing mice was much thinner and displayed a highly irregular surface structure compared to wild type littermates. Teeth of transgenic animals underwent rapid attrition due to the brittleness of the enamel layer. The microstructure of enamel, normally a highly ordered arrangement of hydroxyapatite crystals, was completely disorganized. Tomes' process, the hallmark of secretory stage ameloblasts, did not form in transgenic mice. Collectively our data demonstrate that the overexpression of amelotin has a profound effect on enamel structure by disrupting the formation of Tomes' process and the orderly growth of enamel prisms.

  9. 多孔微载体无血清培养rCHO细胞生产u-PA%Production of u-PA with rCHO Cell Culture on Porous Microcarriers in Serum-free Growth Medium

    Institute of Scientific and Technical Information of China (English)

    胡显文; 肖成祖; 李佐虎; 郭志霞; 高丽华; 张正光; 胥照平; 王菲

    2000-01-01

    . With four-step purification process, about 80 g u-PA(~90 % scu-PA)was recovered from~2100 liters supernatant which contained~135 g u-PA.

  10. Pericellular proteolytic cascade by plasmin/plasminogen activator system

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Plasmin/plasminogen activators (PA) are the serine enzyme which digests fibrin and/or fibrinogen. Plasmin is produced by the cleavage of its precursor, plasminogen by PAs (urokinase-type PA and tissue-type PA). These events are expected in the thrmbolytic therapy for thromboembolic deseases. Apart from the blood fibrinolysis mentioned above, new role of plasmin/plasminogen activators has been extensively investigated in the field of cellular biology. On the cell surface, the receptor for urokinase-type PA (u-PAR) was found (that for t-PA has not cloned yet). Then, plasmin as well as u-PA itself activates pro-form of matrix metalloproteinases (MMPs) around the pericellular space. These proteolytic activities by u-PA, plasmin and MMPs induce the degradation of extracellular matrix (ECM), affording the cells certain enviroment for their biological function. Further, the coupling of u-PA/u-PAR system and integrins can generate intracellular signal transductions which take part in the regulation of cell proliferation, attachment or migration followed by various physiological and pathophysiological functions. These serial mechanisms are the principle of pericellular proteolytic cascade.

  11. Lipid-Based Nanovectors for Targeting of CD44-Overexpressing Tumor Cells

    Directory of Open Access Journals (Sweden)

    Silvia Arpicco

    2013-01-01

    Full Text Available Hyaluronic acid (HA is a naturally occurring glycosaminoglycan that exists in living systems, and it is a major component of the extracellular matrix. The hyaluronic acid receptor CD44 is found at low levels on the surface of epithelial, haematopoietic, and neuronal cells and is overexpressed in many cancer cells particularly in tumour initiating cells. HA has been therefore used as ligand attached to HA-lipid-based nanovectors for the active targeting of small or large active molecules for the treatment of cancer. This paper describes the different approaches employed for the preparation, characterization, and evaluation of these potent delivery systems.

  12. Enhanced tolerance to drought in transgenic rice plants overexpressing C4 photosynthesis enzymes

    Institute of Scientific and Technical Information of China (English)

    Jun-Fei; Gu; Ming; Qiu; Jian-Chang; Yang

    2013-01-01

    Maize-specific pyruvate orthophosphate dikinase(PPDK) was overexpressed in rice independently or in combination with the maize C4-specific phosphoenolpyruvate carboxylase(PCK). The wild-type(WT) cultivar Kitaake and transgenic plants were evaluated in independent field and tank experiments. Three soil moisture treatments,well-watered(WW), moderate drought(MD) and severe drought(SD), were imposed from 9d post-anthesis till maturity. Leaf physiological and biochemical traits, root activities,biomass, grain yield, and yield components in the untransformed WT and two transgenic rice lines(PPDK and PCK) were systematically studied. Compared with the WT, both transgenic rice lines showed increased leaf photosynthetic rate: by 20%–40% under WW, by45%–60% under MD, and by 80%–120% under SD. The transgenic plants produced 16.1%,20.2% and 20.0% higher grain yields than WT under the WW, MD and SD treatments,respectively. Under the same soil moisture treatments, activities of phosphoenolpyruvate carboxylase(PEPC) and carbonic anhydrase(CA) in transgenic plants were 3–5-fold higher than those in WT plants. Compared with ribulose-1,5-bisphosphate carboxylase, activities of PEPC and CA were less reduced under both MD and SD treatments. The transgenic plants also showed higher leaf water content, stomatal conductance, transpiration efficiency, and root oxidation activity and a stronger active oxygen scavenging system than the WT under all soil moisture treatments, especially MD and SD. The results suggest that drought tolerance is greatly enhanced in transgenic rice plants overexpressing C4photosynthesis enzymes. This study was performed under natural conditions and normal planting density to evaluate yield advantages on a field basis. It may open a new avenue to droughttolerance breeding via overexpression of C4enzymes in rice.

  13. Enhanced tolerance to drought in transgenic rice plants overexpressing C4 photosynthesis enzymes

    Directory of Open Access Journals (Sweden)

    Jun-Fei Gu

    2013-12-01

    Full Text Available Maize-specific pyruvate orthophosphate dikinase (PPDK was overexpressed in rice independently or in combination with the maize C4-specific phosphoenolpyruvate carboxylase (PCK. The wild-type (WT cultivar Kitaake and transgenic plants were evaluated in independent field and tank experiments. Three soil moisture treatments, well-watered (WW, moderate drought (MD and severe drought (SD, were imposed from 9 d post-anthesis till maturity. Leaf physiological and biochemical traits, root activities, biomass, grain yield, and yield components in the untransformed WT and two transgenic rice lines (PPDK and PCK were systematically studied. Compared with the WT, both transgenic rice lines showed increased leaf photosynthetic rate: by 20%–40% under WW, by 45%–60% under MD, and by 80%–120% under SD. The transgenic plants produced 16.1%, 20.2% and 20.0% higher grain yields than WT under the WW, MD and SD treatments, respectively. Under the same soil moisture treatments, activities of phosphoenolpyruvate carboxylase (PEPC and carbonic anhydrase (CA in transgenic plants were 3–5-fold higher than those in WT plants. Compared with ribulose-1,5-bisphosphate carboxylase, activities of PEPC and CA were less reduced under both MD and SD treatments. The transgenic plants also showed higher leaf water content, stomatal conductance, transpiration efficiency, and root oxidation activity and a stronger active oxygen scavenging system than the WT under all soil moisture treatments, especially MD and SD. The results suggest that drought tolerance is greatly enhanced in transgenic rice plants overexpressing C4 photosynthesis enzymes. This study was performed under natural conditions and normal planting density to evaluate yield advantages on a field basis. It may open a new avenue to drought-tolerance breeding via overexpression of C4 enzymes in rice.

  14. Brain-targeted angiotensin-converting enzyme 2 overexpression attenuates neurogenic hypertension by inhibiting cyclooxygenase-mediated inflammation.

    Science.gov (United States)

    Sriramula, Srinivas; Xia, Huijing; Xu, Ping; Lazartigues, Eric

    2015-03-01

    Overactivity of the renin-angiotensin system, oxidative stress, and cyclooxygenases (COX) in the brain are implicated in the pathogenesis of hypertension. We previously reported that angiotensin-converting enzyme 2 (ACE2) overexpression in the brain attenuates the development of deoxycorticosterone acetate-salt hypertension, a neurogenic hypertension model with enhanced brain renin-angiotensin system and sympathetic activity. To elucidate the mechanisms involved, we investigated whether oxidative stress, mitogen-activated protein kinase signaling and cyclooxygenase (COX) activation in the brain are modulated by ACE2 in neurogenic hypertension. Deoxycorticosterone acetate-salt hypertension significantly increased expression of Nox-2 (+61±5%), Nox-4 (+50±13%), and nitrotyrosine (+89±32%) and reduced activity of the antioxidant enzymes, catalase (-29±4%) and superoxide dismutase (-31±7%), indicating increased oxidative stress in the brain of nontransgenic mice. This increased oxidative stress was attenuated in transgenic mice overexpressing ACE2 in the brain. Deoxycorticosterone acetate-salt-induced reduction of neuronal nitric oxide synthase expression (-26±7%) and phosphorylated endothelial nitric oxide synthase/total endothelial nitric oxide synthase (-30±3%), and enhanced phosphorylation of protein kinase B and extracellular signal-regulated kinase 1/2 in the paraventricular nucleus, were reversed by ACE2 overexpression. In addition, ACE2 overexpression blunted the hypertension-mediated increase in gene and protein expression of COX-1 and COX-2 in the paraventricular nucleus. Furthermore, gene silencing of either COX-1 or COX-2 in the brain, reduced microglial activation and accompanied neuroinflammation, ultimately attenuating Deoxycorticosterone acetate-salt hypertension. Together, these data provide evidence that brain ACE2 overexpression reduces oxidative stress and COX-mediated neuroinflammation, improves antioxidant and nitric oxide signaling, and

  15. Hepatocellular alterations and dysregulation of oncogenic pathways in the liver of transgenic mice overexpressing growth hormone.

    Science.gov (United States)

    Miquet, Johanna G; Freund, Thomas; Martinez, Carolina S; González, Lorena; Díaz, María E; Micucci, Giannina P; Zotta, Elsa; Boparai, Ravneet K; Bartke, Andrzej; Turyn, Daniel; Sotelo, Ana I

    2013-04-01

    Growth hormone (GH) overexpression throughout life in transgenic mice is associated with the development of liver tumors at old ages. The preneoplastic pathology observed in the liver of young adult GH-overexpressing mice is similar to that present in humans at high risk of hepatic cancer. To elucidate the molecular pathogenesis underlying the pro-oncogenic liver pathology induced by prolonged exposure to elevated GH levels, the activation and expression of several components of signal transduction pathways that have been implicated in hepatocellular carcinogenesis were evaluated in the liver of young adult GH-transgenic mice. In addition, males and females were analyzed in parallel in order to evaluate sexual dimorphism. Transgenic mice from both sexes exhibited hepatocyte hypertrophy with enlarged nuclear size and exacerbated hepatocellular proliferation, which were higher in males. Dysregulation of several oncogenic pathways was observed in the liver of GH-overexpressing transgenic mice. Many signaling mediators and effectors were upregulated in transgenic mice compared with normal controls, including Akt2, NFκB, GSK3β, β-catenin, cyclin D1, cyclin E, c-myc, c-jun and c-fos. The molecular alterations described did not exhibit sexual dimorphism in transgenic mice except for higher gene expression and nuclear localization of cyclin D1 in males. We conclude that prolonged exposure to GH induces in the liver alterations in signaling pathways involved in cell growth, proliferation and survival that resemble those found in many human tumors.

  16. Transgenic mice overexpressing renin exhibit glucose intolerance and diet-genotype interactions

    Directory of Open Access Journals (Sweden)

    Sarah J. Fletcher

    2013-01-01

    Full Text Available Numerous animal and clinical investigations have pointed to a potential role of the renin-angiotensin system (RAS in the development of insulin resistance and diabetes in conditions of expanded fat mass. However, the mechanisms underlying this association remain unclear. We used a transgenic mouse model overexpressing renin in the liver (RenTgMK to examine the effects of chronic activation of RAS on adiposity and insulin sensitivity. Hepatic overexpression of renin resulted in constitutively elevated plasma angiotensin II (4-6-fold increase vs. wild type. Surprisingly, RenTgMK mice developed glucose intolerance despite low levels of adiposity and insulinemia. The transgenics also had lower plasma triglyceride levels. Glucose intolerance in transgenic mice fed a low-fat diet was comparable to that observed in high fat-fed wild type mice. Glucose intolerance was exacerbated by high-fat feeding, only in female transgenic mice. These studies demonstrate that overexpression of renin and associated hyperangiotensinemia impair glucose tolerance in a diet-dependent manner and further support a consistent role of RAS in the pathogenesis of diabetes and insulin resistance, independent of changes in fat mass.

  17. CmMYB19 Over-Expression Improves Aphid Tolerance in Chrysanthemum by Promoting Lignin Synthesis

    Science.gov (United States)

    Wang, Yinjie; Sheng, Liping; Zhang, Huanru; Du, Xinping; An, Cong; Xia, Xiaolong; Chen, Fadi; Jiang, Jiafu; Chen, Sumei

    2017-01-01

    The gene encoding the MYB (v-myb avian myeloblastosis vira l oncogene homolog) transcription factor CmMYB19 was isolated from chrysanthemum. It encodes a 200 amino acid protein and belongs to the R2R3-MYB subfamily. CmMYB19 was not transcriptionally activated in yeast, while a transient expression experiment conducted in onion epidermal cells suggested that the CmMYB19 product localized to the nucleus. CmMYB19 transcription was induced by aphid (Macrosiphoniella sanborni) infestation, and the abundance of transcript was higher in the leaf and stem than in the root. The over-expression of CmMYB19 restricted the multiplication of the aphids. A comparison of transcript abundance of the major genes involved in lignin synthesis showed that CmPAL1 (phenylalanine ammonia lyase 1), CmC4H (cinnamate4 hydroxylase), Cm4CL1 (4-hydroxy cinnamoyl CoA ligase 1), CmHCT (hydroxycinnamoyl CoA-shikimate/quinate hydroxycinnamoyl transferase), CmC3H1 (coumarate3 hydroxylase1), CmCCoAOMT1 (caffeoyl CoA O-methyltransferase 1) and CmCCR1 (cinnamyl CoA reductase1) were all upregulated, in agreement with an increase in lignin content in CmMYB19 over-expressing plants. Collectively, the over-expression of CmMYB19 restricted the multiplication of the aphids on the host, mediated by an enhanced accumulation of lignin. PMID:28287502

  18. Overexpression of poplar cellulase accelerates growth and disturbs the closing movements of leaves in sengon.

    Science.gov (United States)

    Hartati, Sri; Sudarmonowati, Enny; Park, Yong Woo; Kaku, Tomomi; Kaida, Rumi; Baba, Kei'ichi; Hayashi, Takahisa

    2008-06-01

    In this study, poplar (Populus alba) cellulase (PaPopCel1) was overexpressed in a tropical Leguminosae tree, sengon (Paraserianthes falcataria), by the Agrobacterium tumefaciens method. PaPopCel1 overexpression increased the length and width of stems with larger leaves, which showed a moderately higher density of green color than leaves of the wild type. The pairs of leaves on the transgenic plants closed more slowly during sunset than those on the wild-type plants. When main veins from each genotype were excised and placed on a paper towel, however, the leaves of the transgenic plants closed more rapidly than those of the wild-type plant. Based on carbohydrate analyses of cell walls, the leaves of the transgenic plants contained less wall-bound xyloglucan than those of the wild-type plants. In situ xyloglucan endotransglucosylase activity showed that the incorporation of whole xyloglucan, potentially for wall tightening, occurred in the parenchyma cells (motor cells) of the petiolule pulvinus attached to the main vein, although the transgenic plant incorporated less whole xyloglucan than the wild-type plant. These observations support the hypothesis that the paracrystalline sites of cellulose microfibrils are attacked by poplar cellulase, which loosens xyloglucan intercalation, resulting in an irreversible wall modification. This process could be the reason why the overexpression of poplar cellulase both promotes plant growth and disturbs the biological clock of the plant by altering the closing movements of the leaves of the plant.

  19. Conditional Cripto overexpression in satellite cells promotes myogenic commitment and enhances early regeneration.

    Science.gov (United States)

    Prezioso, Carolina; Iaconis, Salvatore; Andolfi, Gennaro; Zentilin, Lorena; Iavarone, Francescopaolo; Guardiola, Ombretta; Minchiotti, Gabriella

    2015-01-01

    Skeletal muscle regeneration mainly depends on satellite cells, a population of resident muscle stem cells. Despite extensive studies, knowledge of the molecular mechanisms underlying the early events associated with satellite cell activation and myogenic commitment in muscle regeneration remains still incomplete. Cripto is a novel regulator of postnatal skeletal muscle regeneration and a promising target for future therapy. Indeed, Cripto is expressed both in myogenic and inflammatory cells in skeletal muscle after acute injury and it is required in the satellite cell compartment to achieve effective muscle regeneration. A critical requirement to further explore the in vivo cellular contribution of Cripto in regulating skeletal muscle regeneration is the possibility to overexpress Cripto in its endogenous configuration and in a cell and time-specific manner. Here we report the generation and the functional characterization of a novel mouse model for conditional expression of Cripto, i.e., the Tg:DsRed (loxP/loxP) Cripto-eGFP mice. Moreover, by using a satellite cell specific Cre-driver line we investigated the biological effect of Cripto overexpression in vivo, and provided evidence that overexpression of Cripto in the adult satellite cell compartment promotes myogenic commitment and differentiation, and enhances early regeneration in a mouse model of acute injury.

  20. Enhanced leavening ability of baker's yeast by overexpression of SNR84 with PGM2 deletion.

    Science.gov (United States)

    Lin, Xue; Zhang, Cui-Ying; Bai, Xiao-Wen; Xiao, Dong-Guang

    2015-06-01

    Dough-leavening ability is one of the main aspects considered when selecting a baker's yeast strain for baking industry. Generally, modification of maltose metabolic pathway and known regulatory networks of maltose metabolism were used to increase maltose metabolism to improve leavening ability in lean dough. In this study, we focus on the effects of PGM2 (encoding for the phosphoglucomutase) and SNR84 (encoding for the H/ACA snoRNA) that are not directly related to both the maltose metabolic pathway and known regulatory networks of maltose metabolism on the leavening ability of baker's yeast in lean dough. The results show that the modifications on PGM2 and/or SNR84 are effective ways in improving leavening ability of baker's yeast in lean dough. Deletion of PGM2 decreased cellular glucose-1-phosphate and overexpression of SNR84 increased the maltose permease activity. These changes resulted in 11, 19 and 21% increases of the leavening ability for PGM2 deletion, SNR84 overexpression and SNR84 overexpression combining deleted PGM2, respectively.

  1. Overexpression of glucose-6-phosphate dehydrogenase is associated with lipid dysregulation and insulin resistance in obesity.

    Science.gov (United States)

    Park, Jiyoung; Rho, Ho Kyung; Kim, Kang Ho; Choe, Sung Sik; Lee, Yun Sok; Kim, Jae Bum

    2005-06-01

    Glucose-6-phosphate dehydrogenase (G6PD) produces cellular NADPH, which is required for the biosynthesis of fatty acids and cholesterol. Although G6PD is required for lipogenesis, it is poorly understood whether G6PD in adipocytes is involved in energy homeostasis, such as lipid and glucose metabolism. We report here that G6PD plays a role in adipogenesis and that its increase is tightly associated with the dysregulation of lipid metabolism and insulin resistance in obesity. We observed that the enzymatic activity and expression levels of G6PD were significantly elevated in white adipose tissues of obese models, including db/db, ob/ob, and diet-induced obesity mice. In 3T3-L1 cells, G6PD overexpression stimulated the expression of most adipocyte marker genes and elevated the levels of cellular free fatty acids, triglyceride, and FFA release. Consistently, G6PD knockdown via small interfering RNA attenuated adipocyte differentiation with less lipid droplet accumulation. Surprisingly, the expression of certain adipocytokines such as tumor necrosis factor alpha and resistin was increased, whereas that of adiponectin was decreased in G6PD overexpressed adipocytes. In accordance with these results, overexpression of G6PD impaired insulin signaling and suppressed insulin-dependent glucose uptake in adipocytes. Taken together, these data strongly suggest that aberrant increase of G6PD in obese and/or diabetic subjects would alter lipid metabolism and adipocytokine expression, thereby resulting in failure of lipid homeostasis and insulin resistance in adipocytes.

  2. Superoxide dismutase overexpression protects against glucocorticoid-induced depressive-like behavioral phenotypes in mice.

    Science.gov (United States)

    Uchihara, Yuki; Tanaka, Ken-ichiro; Asano, Teita; Tamura, Fumiya; Mizushima, Tohru

    2016-01-22

    In the stress response, activation of the hypothalamic-pituitary-adrenal axis, and particularly the release of glucocorticoids, plays a critical role. However, dysregulation of this system and sustained high plasma levels of glucocorticoids can result in depression. Recent studies have suggested the involvement of reactive oxygen species (ROS), such as superoxide anion, in depression. However, direct evidence for a role of ROS in the pathogenesis of this disorder is lacking. In this study, using transgenic mice expressing human Cu/Zn-superoxide dismutase (SOD1), an enzyme that catalyzes the dismutation of superoxide anions, we examined the effect of SOD1 overexpression on depressive-like behavioral phenotypes in mice. Depressive-like behaviors were induced by daily subcutaneous administration of the glucocorticoid corticosterone for 4 weeks, and was monitored with the social interaction test, the sucrose preference test and the forced swim test. These tests revealed that transgenic mice overexpressing SOD1 are more resistant to glucocorticoid-induced depressive-like behavioral disorders than wild-type animals. Furthermore, compared with wild-type mice, transgenic mice showed a reduction in the number of 8-hydroxy-2'-deoxyguanosine (a marker of oxidative stress)-positive cells in the hippocampal CA3 region following corticosterone administration. These results suggest that overexpression of SOD1 protects mice against glucocorticoid-induced depressive-like behaviors by decreasing cellular ROS levels.

  3. CD147 overexpression promotes tumorigenicity in Chinese hamster ovary cells.

    Science.gov (United States)

    Yong, Yu-Le; Liao, Cheng-Gong; Wei, Ding; Chen, Zhi-Nan; Bian, Huijie

    2016-04-01

    CD147 overexpresses in many epithelium-originated tumors and plays an important role in tumor migration and invasion. Most studies aim at the role of CD147 in tumor progression using tumor cell models. However, the influence of abnormal overexpression of CD147 on neoplastic transformation of normal cells is unknown. Here, the role of CD147 in malignant phenotype transformation in CHO cells was investigated. Three CHO cell lines that stably overexpressed CD147 (CHO-CD147), EGFP-CD147 (CHO-EGFP-CD147), and EGFP (CHO-EGFP) were generated by transfection of plasmids containing human CD147, EGFP-human CD147, and EGFP genes into CHO cells. Cell migration and invasion were detected by wound healing and transwell matrix penetration assay. Trypan blue exclusion, MTT, cell cycle analysis, and BrdU cell proliferation assay were used to detect cell viability and cell proliferation. Annexin V-FITC analysis was performed to detect apoptosis. We found that CD147 overexpression promoted the migration and invasion of CHO cells. CD147 accelerated the G1 to S phase transition and enhanced the CHO cell proliferation. Overexpression of CD147 inhibited both early- and late-stages of apoptosis of CHO-CD147 cells, which is caused by serum deprivation. CHO-EGFP-CD147 cells showed an increased anchorage-independent growth compared with CHO-EGFP cells as detected by soft-agar colony formation assay. The tumors formed by CHO-CD147 cells in nude mice were larger and coupled with higher expression of proliferating cell nuclear antigen and Ki-67 than that of CHO cells. In conclusion, human CD147 overexpression induces malignant phenotype in CHO cells.

  4. RAC1b overexpression stimulates proliferation and NF-kB-mediated anti-apoptotic signaling in thyroid cancer cells

    Science.gov (United States)

    Faria, Márcia; Matos, Paulo; Pereira, Teresa; Cabrera, Rafael; Cardoso, Bruno A.; Bugalho, Maria João

    2017-01-01

    Overexpression of tumor-associated RAC1b has been recently highlighted as one of the most promising targets for therapeutic intervention in colon, breast, lung and pancreatic cancer. RAC1b is a hyperactive variant of the small GTPase RAC1 and has been recently shown to be overexpressed in a subset of papillary thyroid carcinomas associated with unfavorable outcome. Using the K1 PTC derived cell line as an in vitro model, we observed that both RAC1 and RAC1b were able to induce a significant increase on NF-kB and cyclin D1 reporter activity. A clear p65 nuclear localization was found in cells transfected with RAC1b-WT, confirming NF-kB canonical pathway activation. Consistently, we observed a RAC1b-mediated decrease in IκBα (NF-kB inhibitor) protein levels. Moreover, we show that RAC1b overexpression stimulates G1/S progression and protects thyroid cells against induced apoptosis, the latter through a process involving the NF-kB pathway. Present data support previous findings suggesting an important role for RAC1b in the development of follicular cell-derived thyroid malignancies and point out NF-kB activation as one of the molecular mechanisms associated with the pro-tumorigenic advantage of RAC1b overexpression in thyroid carcinomas. PMID:28234980

  5. Arabidopsis LOS5/ABA3 overexpression in transgenic tobacco (Nicotiana tabacum cv. Xanthi-nc) results in enhanced drought tolerance.

    Science.gov (United States)

    Yue, Yuesen; Zhang, Mingcai; Zhang, Jiachang; Duan, Liusheng; Li, Zhaohu

    2011-10-01

    Drought is a major environmental stress factor that affects growth and development of plants. Abscisic acid (ABA), osmotically active compounds, and synthesis of specific proteins, such as proteins that scavenge oxygen radicals, are crucial for plants to adapt to water deficit. LOS5/ABA3 (LOS5) encodes molybdenum-cofactor sulfurase, which is a key regulator of ABA biosynthesis. We overexpressed LOS5 in tobacco using Agrobacterium-mediated transformation. Detached leaves of LOS5-overexpressing seedlings showed lower transpirational water loss than that of nontransgenic seedlings in the same period under normal conditions. When subjected to water-deficit stress, transgenic plants showed less wilting, maintained higher water content and better cellular membrane integrity, accumulated higher quantities of ABA and proline, and exhibited higher activities of antioxidant enzymes, i.e., superoxide dismutase, catalase, peroxidase and ascorbate peroxidase, as compared with control plants. Furthermore, LOS5-overexpressing plants treated with 30% polyethylene glycol showed similar performance in cellular membrane protection, ABA and proline accumulation, and activities of catalase and peroxidase to those under drought stress. Thus, overexpression of LOS5 in transgenic tobacco can enhance drought tolerance.

  6. Effects of MAL61 and MAL62 overexpression on maltose fermentation of baker's yeast in lean dough.

    Science.gov (United States)

    Zhang, Cui-Ying; Lin, Xue; Song, Hai-Yan; Xiao, Dong-Guang

    2015-08-01

    The predominant fermentable sugar in lean dough is maltose. To improve the leavening ability of baker's yeast in lean dough, maltose metabolism should be improved. Maltase (alpha-glucosidase, encoded by MAL62) and maltose permease (encoded by MAL61) are the major factors involved in maltose metabolism. The major rate-limiting factor in maltose metabolism and leavening ability of baker's yeast remains unclear. In this work, MAL61 and/or MAL62 overexpression strains were constructed to investigate the decisive factor for maltose metabolism of industrial baker's yeast in lean dough. Our results show that elevated maltose permease activity by MAL61 overexpression yielded less improvement in maltose fermentation compared to elevated maltase activity by MAL62 overexpression. Significant increase in maltase activity by MAL62 overexpression could result in a 44% increase in leavening ability of industrial baker's yeast in lean dough and a 39% increase in maltose metabolism in a medium containing glucose and maltose. Thus, maltase was the rate-limiting factor in maltose fermentation of industrial baker's yeast in lean dough. This study lays a foundation for breeding of industrial baker's yeast for quick dough leavening.

  7. Compensation of the AKT signaling by ERK signaling in transgenic mice hearts overexpressing TRIM72

    Energy Technology Data Exchange (ETDEWEB)

    Ham, Young-Mi, E-mail: youngmi_ham@hms.harvard.edu [College of Life Science and Biotechnology, Korea University, Seoul (Korea, Republic of); Department of Cell Biology, Harvard Medical School, Boston, MA 02115 (United States); Mahoney, Sarah Jane [Department of Cell Biology, Harvard Medical School, Boston, MA 02115 (United States)

    2013-06-10

    The AKT and ERK signaling pathways are known to be involved in cell hypertrophy, proliferation, survival and differentiation. Although there is evidence for crosstalk between these two signaling pathways in cellulo, there is less evidence for cross talk in vivo. Here, we show that crosstalk between AKT and ERK signaling in the hearts of TRIM72-overexpressing transgenic mice (TRIM72-Tg) with alpha-MHC promoter regulates and maintains their heart size. TRIM72, a heart- and skeletal muscle-specific protein, downregulates AKT-mTOR signaling via IRS-1 degradation and reduces the size of rat cardiomyocytes and the size of postnatal TRIM72-Tg hearts. TRIM72 expression was upregulated by hypertrophic inducers in cardiomyocytes, while IRS-1 was downregulated by IGF-1. TRIM72 specifically regulated IGF-1-dependent AKT-mTOR signaling, resulting in a reduction of the size of cardiomyocytes. Postnatal TRIM72-Tg hearts were smaller than control-treated hearts with inhibition of AKT-mTOR signaling. However, adult TRIM72-Tg hearts were larger than of control despite the suppression of AKT-mTOR signaling. Activation of ERK, PKC-α, and JNK were observed to be elevated in adult TRIM72-Tg, and these signals were mediated by ET-1 via the ET receptors A and B. Altogether, these results suggest that AKT signaling regulates cardiac hypertrophy in physiological conditions, and ERK signaling compensates for the absence of AKT signaling during TRIM72 overexpression, leading to pathological hypertrophy. -- Highlights: • TRIM72 inhibits AKT signaling through ubiquitination of IRS-1 in cardiac cells. • TRIM72 regulates the size of cardiac cells. • TRIM72 regulates size of postnatal TRIM72-overexpressing transgenic mice hearts. • Adult TRIM72-overexpressing transgenic mice hearts showed cardiac dysfunction. • Adult TRIM72 transgenic mice hearts showed higher expression of endothelin receptors.

  8. Overexpression of Caspase-1 in adenocarcinoma of pancreas and chronic pancreatitis

    Institute of Scientific and Technical Information of China (English)

    Yin-Mo Yang; Marco Ramadani; Yan-Ting Huang

    2003-01-01

    AIM: To identify the expression of Caspase-l(interleukin1.β converting enzyme) and its role in adenoma of the pancreas and chronic pancreatitis.METHODS: The expression of Caspase-1 was assessed in 42 pancreatic cancer tissue samples, 38 chronic pancreatitis specimens, and 9 normal pancreatic tissues by immunohistochemistry and Western blot analysis.RESULTS: Overexpression of Caspase-1 was observed in both disorders, but there were differences in the expression patterns in distinct morphologic compartments. Pancreatic cancer tissues showed a clear cytoplasmatic overexpression of Caspase-1 in tumor cells of 71% of the tumors, whereas normal pancreatic tissues showed only occasional immunoreactivity. In chronic pancreatitis, overexpression of Caspase-1 was found in atrophic acinar cells (89 %),hyperplastic ducts (87 %), and dedifferentiating acinar cells (84 %). Although in atrophic cells a clear nuclear expression was found, hyperplastic ducts and dedifferentiating acinar cells showed dear cytoplasmic expression. Western blot analysis revealed a marked expression of the 45 kDa precursor of Caspase-1 in pancreatic cancer and chronic pancreatitis (80 %and 86 %, respectively). Clear bands at 30 kDa, which suggested the p10-p20 heterodimer of active Caspase-1, were found in 60 % of the cancer tissue and 14 % of the pancreatitis tissue specimens, but not in normal pancreatic tissues.CONCLUSION: Overexpression of Caspase-1 is a frequent event in pancreatic disorders and its differential expression patterns may reflect two functions of the protease. One is its participation in the apoptotic pathway in atrophic acinar cells and tumor-surrounding pancreatitis tissue, the other is its possible role in proliferative processes in pancreatic cancer cells and hyperplastic duct cells and dedifferentiating acinar cells in chronic pancreatitis.

  9. Towards efficient photosynthesis: overexpression of Zea mays phosphoenolpyruvate carboxylase in Arabidopsis thaliana.

    Science.gov (United States)

    Kandoi, Deepika; Mohanty, Sasmita; Govindjee; Tripathy, Baishnab C

    2016-12-01

    Plants with C4 photosynthesis are efficient in carbon assimilation and have an advantage over C3 photosynthesis. In C4 photosynthesis, the primary CO2 fixation is catalyzed by phosphoenolpyruvate carboxylase (PEPC). Here, we show that overexpression of Zea mays PEPC cDNA, under the control of (35)S promoter, in Arabidopsis thaliana resulted in ~7-10 fold higher protein abundance and ~7-10 fold increase in PEPC activity in the transgenic lines than that in the vector control. We suggest that overexpression of PEPC played an anaplerotic role to increase the supply of 4-carbon carboxylic acids, which provided carbon skeletons for increased amino acid and protein synthesis. Higher protein content must have been responsible for increased metabolic processes including chlorophyll biosynthesis, photosynthesis, and respiration. Consequently, the PEPC-overexpressed transgenic plants had higher chlorophyll content, enhanced electron transport rate (ETR), lower non-photochemical quenching (NPQ) of chlorophyll a fluorescence, and a higher performance index (PI) than the vector control. Consistent with these observations, the rate of CO2 assimilation, the starch content, and the dry weight of PEPC-overexpressed plants increased by 14-18 %, 10-18 %, and 6.5-16 %, respectively. Significantly, transgenics were tolerant to salt stress as they had increased ability to synthesize amino acids, including the osmolyte proline. NaCl (150 mM)-treated transgenic plants had higher variable to maximum Chl a fluorescence (F v/F m) ratio, higher PI, higher ETR, and lower NPQ than the salt-treated vector controls. These results suggest that expression of C4 photosynthesis enzyme(s) in a C3 plant can improve its photosynthetic capacity with enhanced tolerance to salinity stress.

  10. Overexpression of the transcription factor Yap1 modifies intracellular redox conditions and enhances recombinant protein secretion

    Directory of Open Access Journals (Sweden)

    Marizela Delic

    2014-10-01

    Full Text Available Oxidative folding of secretory proteins in the endoplasmic reticulum (ER is a redox active process, which also impacts the redox conditions in the cytosol. As the transcription factor Yap1 is involved in the transcriptional response to oxidative stress, we investigate its role upon the production of secretory proteins, using the yeast Pichia pastoris as model, and report a novel important role of Yap1 during oxidative protein folding. Yap1 is needed for the detoxification of reactive oxygen species (ROS caused by increased oxidative protein folding. Constitutive co-overexpression of PpYAP1 leads to increased levels of secreted recombinant protein, while a lowered Yap1 function leads to accumulation of ROS and strong flocculation. Transcriptional analysis revealed that more than 150 genes were affected by overexpression of YAP1, in particular genes coding for antioxidant enzymes or involved in oxidation-reduction processes. By monitoring intracellular redox conditions within the cytosol and the ER using redox-sensitive roGFP1 variants, we could show that overexpression of YAP1 restores cellular redox conditions of protein-secreting P. pastoris by reoxidizing the cytosolic redox state to the levels of the wild type. These alterations are also reflected by increased levels of oxidized intracellular glutathione (GSSG in the YAP1 co-overexpressing strain. Taken together, these data indicate a strong impact of intracellular redox balance on the secretion of (recombinant proteins without affecting protein folding per se. Re-establishing suitable redox conditions by tuning the antioxidant capacity of the cell reduces metabolic load and cell stress caused by high oxidative protein folding load, thereby increasing the secretion capacity.

  11. Overexpression of a soybean salicylic acid methyltransferase gene confers resistance to soybean cyst nematode.

    Science.gov (United States)

    Lin, Jingyu; Mazarei, Mitra; Zhao, Nan; Zhu, Junwei J; Zhuang, Xiaofeng; Liu, Wusheng; Pantalone, Vincent R; Arelli, Prakash R; Stewart, Charles N; Chen, Feng

    2013-12-01

    Salicylic acid plays a critical role in activating plant defence responses after pathogen attack. Salicylic acid methyltransferase (SAMT) modulates the level of salicylic acid by converting salicylic acid to methyl salicylate. Here, we report that a SAMT gene from soybean (GmSAMT1) plays a role in soybean defence against soybean cyst nematode (Heterodera glycines Ichinohe, SCN). GmSAMT1 was identified as a candidate SCN defence-related gene in our previous analysis of soybean defence against SCN using GeneChip microarray experiments. The current study started with the isolation of the full-length cDNAs of GmSAMT1 from a SCN-resistant soybean line and from a SCN-susceptible soybean line. The two cDNAs encode proteins of identical sequences. The GmSAMT1 cDNA was expressed in Escherichia coli. Using in vitro enzyme assays, E. coli-expressed GmSAMT1 was confirmed to function as salicylic acid methyltransferase. The apparent Km value of GmSAMT1 for salicylic acid was approximately 46 μM. To determine the role of GmSAMT1 in soybean defence against SCN, transgenic hairy roots overexpressing GmSAMT1 were produced and tested for SCN resistance. Overexpression of GmSAMT1 in SCN-susceptible backgrounds significantly reduced the development of SCN, indicating that overexpression of GmSAMT1 in the transgenic hairy root system could confer resistance to SCN. Overexpression of GmSAMT1 in transgenic hairy roots was also found to affect the expression of selected genes involved in salicylic acid biosynthesis and salicylic acid signal transduction.

  12. Matrix metalloproteinase-8 overexpression prevents proper tissue repair

    DEFF Research Database (Denmark)

    Danielsen, Patricia Louise; Holst, Anders V; Maltesen, Henrik R

    2011-01-01

    The collagenolytic matrix metalloproteinase-8 (MMP-8) is essential for normal tissue repair but is often overexpressed in wounds with disrupted healing. Our aim was to study the impact of a local excess of this neutrophil-derived proteinase on wound healing using recombinant adenovirus-driven tra......The collagenolytic matrix metalloproteinase-8 (MMP-8) is essential for normal tissue repair but is often overexpressed in wounds with disrupted healing. Our aim was to study the impact of a local excess of this neutrophil-derived proteinase on wound healing using recombinant adenovirus...

  13. Positive fluorescent selection permits precise, rapid, and in-depth overexpression analysis in plant protoplasts.

    Science.gov (United States)

    Bargmann, Bastiaan O R; Birnbaum, Kenneth D

    2009-03-01

    Transient genetic modification of plant protoplasts is a straightforward and rapid technique for the study of numerous aspects of plant biology. Recent studies in metazoan systems have utilized cell-based assays to interrogate signal transduction pathways using high-throughput methods. Plant biologists could benefit from new tools that expand the use of cell culture for large-scale analysis of gene function. We have developed a system that employs fluorescent positive selection in combination with flow cytometric analysis and fluorescence-activated cell sorting to isolate responses in the transformed protoplasts exclusively. The system overcomes the drawback that transfected protoplast suspensions are often a heterogeneous mix of cells that have and have not been successfully transformed. This Gateway-compatible system enables high-throughput screening of genetic circuitry using overexpression. The incorporation of a red fluorescent protein selection marker enables combined utilization with widely available green fluorescent protein (GFP) tools. For instance, such a dual labeling approach allows cytometric analysis of GFP reporter gene activation expressly in the transformed cells or fluorescence-activated cell sorting-mediated isolation and downstream examination of overexpression effects in a specific GFP-marked cell population. Here, as an example, novel uses of this system are applied to the study of auxin signaling, exploiting the red fluorescent protein/GFP dual labeling capability. In response to manipulation of the auxin response network through overexpression of dominant negative auxin signaling components, we quantify effects on auxin-responsive DR5::GFP reporter gene activation as well as profile genome-wide transcriptional changes specifically in cells expressing a root epidermal marker.

  14. BAK overexpression mediates p53-independent apoptosis inducing effects on human gastric cancer cells

    Directory of Open Access Journals (Sweden)

    Liu Jun

    2004-07-01

    Full Text Available Abstract Background BAK (Bcl-2 homologous antagonist/killer is a novel pro-apoptotic gene of the Bcl-2 family. It has been reported that gastric tumors have reduced BAK levels when compared with the normal mucosa. Moreover, mutations of the BAK gene have been identified in human gastrointestinal cancers, suggesting that a perturbation of BAK-mediated apoptosis may contribute to the pathogenesis of gastric cancer. In this study, we explored the therapeutic effects of gene transfer mediated elevations in BAK expression on human gastric cancer cells in vitro. Methods Eukaryotic expression vector for the BAK gene was constructed and transferred into gastric cancer cell lines, MKN-45 (wild-type p53 and MKN-28 (mutant-type p53. RT-PCR and Western Blotting detected cellular BAK gene expression. Cell growth activities were detected by MTT colorimetry and flow cytometry, while apoptosis was assayed by electronic microscopy and TUNEL. Western Blotting and colorimetry investigated cellular caspase-3 activities. Results BAK gene transfer could result in significant BAK overexpression, decreased in vitro growth, cell cycle G0/G1 arrest, and induced apoptosis in gastric cancer cells. In transferred cells, inactive caspase-3 precursor was cleaved into the active subunits p20 and p17, during BAK overexpression-induced apoptosis. In addition, this process occurred equally well in p53 wild-type (MKN-45, or in p53 mutant-type (MKN-28 gastric cancer cells. Conclusions The data presented suggests that overexpression of the BAK gene can lead to apoptosis of gastric cancer cells in vitro, which does not appear to be dependent on p53 status. The action mechanism of BAK mediated apoptosis correlates with activation of caspase-3. This could be served as a potential strategy for further development of gastric cancer therapies.

  15. SIX1 overexpression predicts poor prognosis and induces radioresistance through AKT signaling in esophageal squamous cell carcinoma

    Science.gov (United States)

    He, Zheng; Li, Guang; Tang, Lingrong; Li, Yaming

    2017-01-01

    The Sineoculis homeobox homolog 1 (SIX1) protein has been found to be overexpressed in several human cancers. However, its expression pattern and biological roles in esophageal squamous cell carcinoma (ESCC) remain unexplored. This study examined the clinical significance of SIX1 in 119 ESCC tissues. It was found that SIX1 protein was upregulated in 36.9% (44/119) cases. SIX1 overexpression was an independent predictor for short survival of ESCC patients. siRNA knockdown and plasmid transfection were carried out in ESCC cell lines. SIX1 depletion inhibited cell growth, invasion, and colony formation, whereas its overexpression facilitated in vivo and in vitro cell growth, invasion, and colony formation. The apoptosis rate induced by X-ray irradiation was substantially increased by SIX1 knockdown in Eca-109 cells. Ectopic overexpression of SIX1 in TE-1 cells dramatically enhanced resistance to irradiation. Western blot analysis showed that SIX1 depletion downregulated cyclin E, matrix metalloproteinase-2 (MMP-2), Bcl-2 expression and upregulated Bim expression. SIX1 overexpression exhibited the opposite effect on these proteins. In addition, it was found that SIX1 could positively regulate extracellular signal-regulated kinase (ERK) and AKT signaling pathway. ERK inhibitor abolished the effect of SIX1 on MMP-2 expression. AKT inhibitor treatment blocked the role of SIX1 on anti-apoptotic protein Bcl-2. In conclusion, this study demonstrates that SIX1 overexpression predicts poor survival in ESCC patients and confers radioresistance through activation of AKT signaling pathways. PMID:28260921

  16. Urokinase plasminogen activator inhibits HIV virion release from macrophage-differentiated chronically infected cells via activation of RhoA and PKCε.

    Directory of Open Access Journals (Sweden)

    Francesca Graziano

    Full Text Available BACKGROUND: HIV replication in mononuclear phagocytes is a multi-step process regulated by viral and cellular proteins with the peculiar feature of virion budding and accumulation in intra-cytoplasmic vesicles. Interaction of urokinase-type plasminogen activator (uPA with its cell surface receptor (uPAR has been shown to favor virion accumulation in such sub-cellular compartment in primary monocyte-derived macrophages and chronically infected promonocytic U1 cells differentiated into macrophage-like cells by stimulation with phorbol myristate acetate (PMA. By adopting this latter model system, we have here investigated which intracellular signaling pathways were triggered by uPA/uPAR interaction leading the redirection of virion accumulation in intra-cytoplasmic vesicles. RESULTS: uPA induced activation of RhoA, PKCδ and PKCε in PMA-differentiated U1 cells. In the same conditions, RhoA, PKCδ and PKCε modulated uPA-induced cell adhesion and polarization, whereas only RhoA and PKCε were also responsible for the redirection of virions in intracellular vesicles. Distribution of G and F actin revealed that uPA reorganized the cytoskeleton in both adherent and polarized cells. The role of G and F actin isoforms was unveiled by the use of cytochalasin D, a cell-permeable fungal toxin that prevents F actin polymerization. Receptor-independent cytoskeleton remodeling by Cytochalasin D resulted in cell adhesion, polarization and intracellular accumulation of HIV virions similar to the effects gained with uPA. CONCLUSIONS: These findings illustrate the potential contribution of the uPA/uPAR system in the generation and/or maintenance of intra-cytoplasmic vesicles that actively accumulate virions, thus sustaining the presence of HIV reservoirs of macrophage origin. In addition, our observations also provide evidences that pathways controlling cytoskeleton remodeling and activation of PKCε bear relevance for the design of new antiviral strategies aimed

  17. APRIL is overexpressed in cancer: link with tumor progression

    Directory of Open Access Journals (Sweden)

    Veyrune Jean-Luc

    2009-03-01

    Full Text Available Abstract Background BAFF and APRIL share two receptors – TACI and BCMA – and BAFF binds to a third receptor, BAFF-R. Increased expression of BAFF and APRIL is noted in hematological malignancies. BAFF and APRIL are essential for the survival of normal and malignant B lymphocytes, and altered expression of BAFF or APRIL or of their receptors (BCMA, TACI, or BAFF-R have been reported in various B-cell malignancies including B-cell non-Hodgkin's lymphoma, chronic lymphocytic leukemia, Hodgkin's lymphoma, multiple myeloma, and Waldenstrom's macroglobulinemia. Methods We compared the expression of BAFF, APRIL, TACI and BAFF-R gene expression in 40 human tumor types – brain, epithelial, lymphoid, germ cells – to that of their normal tissue counterparts using publicly available gene expression data, including the Oncomine Cancer Microarray database. Results We found significant overexpression of TACI in multiple myeloma and thyroid carcinoma and an association between TACI expression and prognosis in lymphoma. Furthermore, BAFF and APRIL are overexpressed in many cancers and we show that APRIL expression is associated with tumor progression. We also found overexpression of at least one proteoglycan with heparan sulfate chains (HS, which are coreceptors for APRIL and TACI, in tumors where APRIL is either overexpressed or is a prognostic factor. APRIL could induce survival or proliferation directly through HS proteoglycans. Conclusion Taken together, these data suggest that APRIL is a potential prognostic factor for a large array of malignancies.

  18. Neuroglobin-overexpression reduces traumatic brain lesion size in mice

    Directory of Open Access Journals (Sweden)

    Zhao Song

    2012-06-01

    Full Text Available Abstract Background Accumulating evidence has demonstrated that over-expression of Neuroglobin (Ngb is neuroprotective against hypoxic/ischemic brain injuries. In this study we tested the neuroprotective effects of Ngb over-expression against traumatic brain injury (TBI in mice. Results Both Ngb over-expression transgenic (Ngb-Tg and wild-type (WT control mice were subjected to TBI induced by a controlled cortical impact (CCI device. TBI significantly increased Ngb expression in the brains of both WT and Ngb-Tg mice, but Ngb-Tg mice had significantly higher Ngb protein levels at the pre-injury baseline and post-TBI. Production of oxidative tissue damage biomarker 3NT in the brain was significantly reduced in Ngb-Tg mice compared to WT controls at 6 hours after TBI. The traumatic brain lesion volume was significantly reduced in Ngb Tg mice compared to WT mice at 3 weeks after TBI; however, there were no significant differences in the recovery of sensorimotor and spatial memory functional deficits between Ngb-Tg and WT control mice for up to 3 weeks after TBI. Conclusion Ngb over-expression reduced traumatic lesion volume, which might partially be achieved by decreasing oxidative stress.

  19. Over-expression of cyclooxygenase-2 in human prostate adenocarcinoma.

    Science.gov (United States)

    Gupta, S; Srivastava, M; Ahmad, N; Bostwick, D G; Mukhtar, H

    2000-01-01

    Aberrant or increased expression of cyclooxygenase (COX)-2 has been implicated in the pathogenesis of many diseases including carcinogenesis. COX-2 has been shown to be over-expressed in some human cancers. Employing semi-quantitative reverse transcription-PCR, immunoblotting, and immunohistochemistry we assessed COX-2 expression in samples of pair-matched benign and cancer tissue obtained from the same prostate cancer patient. Mean levels of COX-2 mRNA were 3.4-fold higher in prostate cancer tissue (n = 12) compared with the paired benign tissue. The immunoblot analysis demonstrated that as compared to benign tissue COX-2 protein was over-expressed in 10 of 12 samples examined. Immunohistochemical analysis also verified COX-2 over-expression in cancer than in benign tissue. To our knowledge, this is the first in vivo study showing an over-expression of COX-2 in prostate cancer. These data suggest that COX-2 inhibitors may be useful for prevention or therapy of prostate cancer in humans.

  20. Optimization of membrane protein overexpression and purification using GFP fusions

    NARCIS (Netherlands)

    Drew, David; Lerch, Mirjam; Kunji, Edmund; Slotboom, Dirk-Jan; de Gier, Jan-Willem

    2006-01-01

    Optimizing conditions for the overexpression and purification of membrane proteins for functional and structural studies is usually a Laborious and time-consuming process. This process can be accelerated using membrane protein-GFP fusions(1-3), which allows direct monitoring and visualization of mem

  1. Pleiotropic effect of sigE over-expression on cell morphology, photosynthesis and hydrogen production in Synechocystis sp. PCC 6803.

    Science.gov (United States)

    Osanai, Takashi; Kuwahara, Ayuko; Iijima, Hiroko; Toyooka, Kiminori; Sato, Mayuko; Tanaka, Kan; Ikeuchi, Masahiko; Saito, Kazuki; Hirai, Masami Yokota

    2013-11-01

    Over-expression of sigE, a gene encoding an RNA polymerase sigma factor in the unicellular cyanobacterium Synechocystis sp. PCC 6803, is known to activate sugar catabolism and bioplastic production. In this study, we investigated the effects of sigE over-expression on cell morphology, photosynthesis and hydrogen production in this cyanobacterium. Transmission electron and scanning probe microscopic analyses revealed that sigE over-expression increased the cell size, possibly as a result of aberrant cell division. Over-expression of sigE reduced respiration and photosynthesis activities via changes in gene expression and chlorophyll fluorescence. Hydrogen production under micro-oxic conditions is enhanced in sigE over-expressing cells. Despite these pleiotropic phenotypes, the sigE over-expressing strain showed normal cell viability under both nitrogen-replete and nitrogen-depleted conditions. These results provide insights into the inter-relationship among metabolism, cell morphology, photosynthesis and hydrogen production in this unicellular cyanobacterium.

  2. KLF5 overexpression attenuates cardiomyocyte inflammation induced by oxygen-glucose deprivation/reperfusion through the PPARγ/PGC-1α/TNF-α signaling pathway.

    Science.gov (United States)

    Li, Yang; Li, Jian; Hou, Zhiwen; Yu, Yang; Yu, Bo

    2016-12-01

    The primary physiological function of Krüppel-like zinc-finger transcription factor (KLF5) is the regulation of cardiovascular remodeling. Vascular remodeling is closely related to the amelioration of various ischemic diseases. However, the underlying correlation of KLF5 and ischemia is not clear. In this study, we aim to investigate the role of KLF5 in myocardial ischemia reperfusion (IR) injury and the potential mechanisms involved. Cultured H9C2 cells were subjected to oxygen-glucose deprivation/reperfusion (OGD/Rep) to mimic myocardial IR injury in vivo. Expressions of KLF5 and PPARγ were distinctly inhibited, and PGC-1α expression was activated at 24h after myocardial OGD/Rep injury. After myocardial OGD/Rep injury, we found that KLF5 overexpression down-regulated levels of TNF-α, IL-1β, IL-6 and IL-8. Through the analysis of lactate dehydrogenase (LDH) release, we demonstrate that KLF5 overexpression reduced the release of OGD/Rep-induced LDH. KLF5 overexpression significantly enhanced cell activity and decreased cell apoptosis during OGD/Rep injury. Compared with the OGD/Rep group, cells overexpressing KLF5 showed anti-apoptotic effects, such as decreased expression of Bax and cleaved caspase-3 as well as increased Bcl-2 expression. KLF5 overexpression activated PPARγ, a protein involved in OGD/Rep injury, and increased levels of PGC-1α, while TNF-α expression was remarkably inhibited. In addition, GW9662, a PPARγ receptor antagonist, reversed the expression of PPARγ/PGC-1α/TNF-α and cell activity induced by KLF5 overexpression. The effects of KLF5 overexpression on PPARγ/PGC-1α/TNF-α and cell activity were abolished by co-treatment with GW9662. Taken together, these results suggest that KLF5 can efficiently alleviate OGD/Rep-induced myocardial injury, perhaps through regulation of the PPARγ/PGC-1α/TNF-α pathway.

  3. DEK over-expression promotes mitotic defects and micronucleus formation.

    Science.gov (United States)

    Matrka, Marie C; Hennigan, Robert F; Kappes, Ferdinand; DeLay, Monica L; Lambert, Paul F; Aronow, Bruce J; Wells, Susanne I

    2015-01-01

    The DEK gene encodes a nuclear protein that binds chromatin and is involved in various fundamental nuclear processes including transcription, RNA splicing, DNA replication and DNA repair. Several cancer types characteristically over-express DEK at the earliest stages of transformation. In order to explore relevant mechanisms whereby DEK supports oncogenicity, we utilized cancer databases to identify gene transcripts whose expression patterns are tightly correlated with that of DEK. We identified an enrichment of genes involved in mitosis and thus investigated the regulation and possible function of DEK in cell division. Immunofluorescence analyses revealed that DEK dissociates from DNA in early prophase and re-associates with DNA during telophase in human keratinocytes. Mitotic cell populations displayed a sharp reduction in DEK protein levels compared to the corresponding interphase population, suggesting DEK may be degraded or otherwise removed from the cell prior to mitosis. Interestingly, DEK overexpression stimulated its own aberrant association with chromatin throughout mitosis. Furthermore, DEK co-localized with anaphase bridges, chromosome fragments, and micronuclei, suggesting a specific association with mitotically defective chromosomes. We found that DEK over-expression in both non-transformed and transformed cells is sufficient to stimulate micronucleus formation. These data support a model wherein normal chromosomal clearance of DEK is required for maintenance of high fidelity cell division and chromosomal integrity. Therefore, the overexpression of DEK and its incomplete removal from mitotic chromosomes promotes genomic instability through the generation of genetically abnormal daughter cells. Consequently, DEK over-expression may be involved in the initial steps of developing oncogenic mutations in cells leading to cancer initiation.

  4. Overexpression of AtBMI1C, a polycomb group protein gene, accelerates flowering in Arabidopsis.

    Directory of Open Access Journals (Sweden)

    Wei Li

    Full Text Available Polycomb group protein (PcG-mediated gene silencing is emerging as an essential developmental regulatory mechanism in eukaryotic organisms. PcGs inactivate or maintain the silenced state of their target chromatin by forming complexes, including Polycomb Repressive Complex 1 (PRC1 and 2 (PRC2. Three PRC2 complexes have been identified and characterized in Arabidopsis; of these, the EMF and VRN complexes suppress flowering by catalyzing the trimethylation of lysine 27 on histone H3 of FLOWER LOCUS T (FT and FLOWER LOCUS C (FLC. However, little is known about the role of PRC1 in regulating the floral transition, although AtRING1A, AtRING1B, AtBMI1A, and AtBMI1B are believed to regulate shoot apical meristem and embryonic development as components of PRC1. Moreover, among the five RING finger PcGs in the Arabidopsis genome, four have been characterized. Here, we report that the fifth, AtBMI1C, is a novel, ubiquitously expressed nuclear PcG protein and part of PRC1, which is evolutionarily conserved with Psc and BMI1. Overexpression of AtBMI1C caused increased H2A monoubiquitination and flowering defects in Arabidopsis. Both the suppression of FLC and activation of FT were observed in AtBMI1C-overexpressing lines, resulting in early flowering. No change in the H3K27me3 level in FLC chromatin was detected in an AtBMI1C-overexpressing line. Our results suggest that AtBMI1C participates in flowering time control by regulating the expression of FLC; moreover, the repression of FLC by AtBMI1C is not due to the activity of PRC2. Instead, it is likely the result of PRC1 activity, into which AtBMI1C is integrated.

  5. Overexpression of Catalase Enhances Benzo(a)pyrene Detoxification in Endothelial Microsomes

    Science.gov (United States)

    Yang, Fang; Yang, Hong; Ramesh, Aramandla; Goodwin, J. Shawn; Okoro, Emmanuel U.; Guo, ZhongMao

    2016-01-01

    We previously reported that overexpression of catalase upregulated xenobiotic- metabolizing enzyme (XME) expression and diminished benzo(a)pyrene (BaP) intermediate accumulation in mouse aortic endothelial cells (MAECs). Endoplasmic reticulum (ER) is the most active organelle involved in BaP metabolism. To examine the involvement of ER in catalase-induced BaP detoxification, we compared the level and distribution of XMEs, and the profile of BaP intermediates in the microsomes of wild-type and catalase transgenic endothelial cells. Our data showed that endothelial microsomes were enriched in cytochrome P450 (CYP) 1A1, CYP1B1 and epoxide hydrolase 1 (EH1), and contained considerable levels of NAD(P)H: quinone oxidoreductase-1 (NQO1) and glutathione S-transferase-pi (GSTP). Treatment of wild-type MAECs with 1μM BaP for 2 h increased the expression of microsomal CYP1A1, 1B1 and NQO1 by ~300, 64 and 116%, respectively. However, the same treatment did not significantly alter the expression of EH1 and GSTP. Overexpression of catalase did not significantly increase EH1, but upregulated BaP-induced expression of microsomal CYP1A1, 1B1, NQO1 and GSTP in the following order: 1A1>NQO1>GSTP>1B1. Overexpression of catalase did not alter the distribution of each of these enzymes in the microsomes. In contrast to our previous report showing lower level of BaP phenols versus BaP diols/diones in the whole-cell, this report demonstrated that the sum of microsomal BaP phenolic metabolites were ~60% greater than that of the BaP diols/diones after exposure of microsomes to BaP. Overexpression of catalase reduced the concentrations of microsomal BaP phenols and diols/diones by ~45 and 95%, respectively. This process enhanced the ratio of BaP phenol versus diol/dione metabolites in a potent manner. Taken together, upregulation of phase II XMEs and CYP1 proteins, but not EH1 in the ER might be the mechanism by which overexpression of catalase reduces the levels of all the BaP metabolites

  6. Expression profiling in transgenic FVB/N embryonic stem cells overexpressing STAT3

    Directory of Open Access Journals (Sweden)

    Yokota Takashi

    2008-05-01

    Full Text Available Abstract Background The transcription factor STAT3 is a downstream target of the LIF signalling cascade. LIF signalling or activation is sufficient to maintain embryonic stem (ES cells in an undifferentiated and pluripotent state. To further investigate the importance of STAT3 in the establishment of ES cells we have in a first step derived stable pluripotent embryonic stem cells from transgenic FVB mice expressing a conditional tamoxifen dependent STAT3-MER fusion protein. In a second step, STAT3-MER overexpressing cells were used to identify STAT3 pathway-related genes by expression profiling in order to identify new key-players involved in maintenance of pluripotency in ES cells. Results Transgenic STAT3-MER blastocysts yielded pluripotent germline-competent ES cells at a high frequency in the absence of LIF when established in tamoxifen-containing medium. Expression profiling of tamoxifen-induced transgenic FVB ES cell lines revealed a set of 26 genes that were markedly up- or down-regulated when compared with wild type cells. The expression of four of the up-regulated genes (Hexokinase II, Lefty2, Pramel7, PP1rs15B was shown to be restricted to the inner cell mass (ICM of the blastocysts. These differentially expressed genes represent potential candidates for the maintenance of pluripotency of ES cells. We finally overexpressed two candidate genes, Pem/Rhox5 and Pramel7, in ES cells and demonstrated that their overexpression is sufficient for the maintenance of expression of ES cell markers as well as of the typical morphology of pluripotent ES cells in absence of LIF. Conclusion Overexpression of STAT3-MER in the inner cell mass of blastocyst facilitates the establishment of ES cells and induces the upregulation of potential candidate genes involved in the maintenance of pluripotency. Two of them, Pem/Rhox5 and Pramel7, when overexpressed in ES cells are able to maintain the embryonic stem cells in a pluripotent state in a LIF independent

  7. Overexpression of MexAB-OprM efflux pump in carbapenem-resistant Pseudomonas aeruginosa.

    Science.gov (United States)

    Pan, Ya-Ping; Xu, Yuan-Hong; Wang, Zhong-Xin; Fang, Ya-Ping; Shen, Ji-Lu

    2016-08-01

    Efflux pump systems are one of the most important mechanisms conferring multidrug resistance in Pseudomonas aeruginosa. MexAB-OprM efflux pump is one of the largest multi-drug resistant efflux pumps with high-level expression, which is controlled by regulatory genes mexR, nalC, and nalD. This study investigated the role of efflux pump MexAB-OprM in 75 strains of carbapenem-resistant P. aeruginosa and evaluated the influence of point mutation of the regulatory genes. The minimum inhibitory concentrations of imipenem and meropenem, with or without MC207110, an efflux pump inhibitor, were determined by agar dilution method to select the positive strains for an overexpressed active efflux pump. Carba NP test and EDTA-disk synergy test were used for the detection of carbapenemase and metallo-β-lactamases, respectively. The gene mexA, responsible for the fusion protein structure, and the reference gene rpoD of the MexAB-OprM pump were amplified by real-time PCR. The quantity of relative mRNA expression was determined simultaneously. By PCR method, the efflux regulatory genes mexR, nalC, and nalD and outer membrane protein OprD2 were amplified for the strains showing overexpression of MexAB-OprM and subsequently analyzed by BLAST. Among the 75 P. aeruginosa strains, the prevalence of efflux pump-positive phenotype was 17.3 % (13/75). Carba NP test and EDTA-disk synergy test were all negative in the 13 strains. PCR assay results showed that ten strains overexpressed the MexAB-OprM efflux pump and were all positive for the regulatory genes mexR, nalC, and nalD. Sequence analysis indicated that of the ten isolates, nine had a mutation (Gly → Glu) at 71st amino acid position in NalC, and eight also had a mutation (Ser → Arg) at 209th position in NalC. Only one strain had a mutation (Thr → Ile) at the 158th amino acid position in NalD, whereas eight isolates had mutations in MexR. In conclusion, overexpression of efflux pump MexAB-OprM plays an important role in

  8. Production of transgenic pigs over-expressing the antiviral gene Mx1

    OpenAIRE

    2014-01-01

    The myxovirus resistance gene (Mx1) has a broad spectrum of antiviral activities. It is therefore an interesting candidate gene to improve disease resistance in farm animals. In this study, we report the use of somatic cell nuclear transfer (SCNT) to produce transgenic pigs over-expressing the Mx1 gene. These transgenic pigs express approximately 15–25 times more Mx1 mRNA than non-transgenic pigs, and the protein level of Mx1 was also markedly enhanced. We challenged fibroblast cells isolated...

  9. Glycomic and sialoproteomic data of gastric carcinoma cells overexpressing ST3GAL4

    DEFF Research Database (Denmark)

    Mereiter, Stefan; Magalhães, Ana; Adamczyk, Barbara

    2016-01-01

    Gastric carcinoma MKN45 cells stably transfected with the full-length ST3GAL4 gene were characterised by glycomic and sialoproteomic analysis. Complementary strategies were applied to assess the glycomic alterations induced by ST3GAL4 overexpression. The N- and O-glycome data were generated in two......-MS/MS identification was performed. This analysis identified 47 proteins with significantly increased sialylation. The data in this article is associated with the research article published in Biochim Biophys Acta "Glycomic analysis of gastric carcinoma cells discloses glycans as modulators of RON receptor tyrosine...... kinase activation in cancer" [1]....

  10. Role of adenosine A2b receptor overexpression in tumor progression.

    Science.gov (United States)

    Sepúlveda, Cesar; Palomo, Iván; Fuentes, Eduardo

    2016-12-01

    The adenosine A2b receptor is a G-protein coupled receptor. Its activation occurs with high extracellular adenosine concentration, for example in inflammation or hypoxia. These conditions are generated in the tumor environment. Studies show that A2b receptor is overexpressed in various tumor lines and biopsies from patients with different cancers. This suggests that A2b receptor can be used by tumor cells to promote progression. Thus A2b participates in different events, such as angiogenesis and metastasis, besides exerting immunomodulatory effects that protect tumor cells. Therefore, adenosine A2b receptor appears as an interesting therapeutic target for cancer treatment.

  11. Proline iminopeptidase PepI overexpressing Lactobacillus casei as an adjunct starter in Edam cheese

    Science.gov (United States)

    Navidghasemizad, Sahar; Takala, Timo M; Alatossava, Tapani; Saris, Per EJ

    2013-01-01

    In this study the growth of genetically modified Lactobacillus casei LAB6, overexpressing proline iminopeptidase PepI and its capacity to increase free proline was investigated during ripening of Edam cheese. The strain successfully survived 12 weeks of ripening period in cheese. The food-grade plasmid pLEB604, carrying the pepI gene, was stable, and PepI enzyme was active in LAB6 cells isolated at different stages of the ripening process. However, HPLC analyses indicated that Lb. casei LAB6 could not increase the amount of free proline in ripened cheese. PMID:23851577

  12. Overexpression of Arabidopsis molybdenum cofactor sulfurase gene confers drought tolerance in maize (Zea mays L.).

    Science.gov (United States)

    Lu, Yao; Li, Yajun; Zhang, Jiachang; Xiao, Yitao; Yue, Yuesen; Duan, Liusheng; Zhang, Mingcai; Li, Zhaohu

    2013-01-01

    Abscisic acid (ABA) is a key component of the signaling system that integrates plant adaptive responses to abiotic stress. Overexpression of Arabidopsis molybdenum cofactor sulfurase gene (LOS5) in maize markedly enhanced the expression of ZmAO and aldehyde oxidase (AO) activity, leading to ABA accumulation and increased drought tolerance. Transgenic maize (Zea mays L.) exhibited the expected reductions in stomatal aperture, which led to decreased water loss and maintenance of higher relative water content (RWC) and leaf water potential. Also, transgenic maize subjected to drought treatment exhibited lower leaf wilting, electrolyte leakage, malondialdehyde (MDA) and H(2)O(2) content, and higher activities of antioxidative enzymes and proline content compared to wild-type (WT) maize. Moreover, overexpression of LOS5 enhanced the expression of stress-regulated genes such as Rad 17, NCED1, CAT1, and ZmP5CS1 under drought stress conditions, and increased root system development and biomass yield after re-watering. The increased drought tolerance in transgenic plants was associated with ABA accumulation via activated AO and expression of stress-related gene via ABA induction, which sequentially induced a set of favorable stress-related physiological and biochemical responses.

  13. Over-Expression of BnMAPK1 in Brassica napus Enhances Tolerance to Drought Stress

    Institute of Scientific and Technical Information of China (English)

    WENG Chang-mei; LU Jun-xing; WAN Hua-fang; WANG Shu-wen; WANG Zhen; LU Kun; LIANG Ying

    2014-01-01

    Mitogen-activated protein kinases (MAPKs) are a family of Ser/Thr protein kinases widely conserved in all eukaryotes and involved in responses to biotic and abiotic stresses. In this study, two over-expressing BnMAPK1 oilseed rape lines, ov3 and ov11, were used to study the drought-resistant mechanism of BnMAPK1 under natural drought and simulation drought through spraying 10%PEG 8000 in seedlings. Zhongyou 821 (WT) was used as control. Compared with wild type, transgenic seedlings had higher leaf water content, higher root activity, slightly higher peroxidase (POD) and superoxide dismutase (SOD) activity, higher proline content and lower malondialdehyde (MDA) content. The expression of drought-resistant related genes, including P5CSB, PLC, LEA4 and SCE1, have been up-regulated in some degree and the expressed time of transgenic lines were earlier than that of wild type. These results suggested that over-expression of BnMAPK1 can enhance the resistance to drought in oilseed rape (Brassica napus).

  14. Overexpression of uncoupling protein 3 in skeletal muscle protects against fat-induced insulin resistance

    Science.gov (United States)

    Choi, Cheol Soo; Fillmore, Jonathan J.; Kim, Jason K.; Liu, Zhen-Xiang; Kim, Sheene; Collier, Emily F.; Kulkarni, Ameya; Distefano, Alberto; Hwang, Yu-Jin; Kahn, Mario; Chen, Yan; Yu, Chunli; Moore, Irene K.; Reznick, Richard M.; Higashimori, Takamasa; Shulman, Gerald I.

    2007-01-01

    Insulin resistance is a major factor in the pathogenesis of type 2 diabetes and is strongly associated with obesity. Increased concentrations of intracellular fatty acid metabolites have been postulated to interfere with insulin signaling by activation of a serine kinase cascade involving PKCθ in skeletal muscle. Uncoupling protein 3 (UCP3) has been postulated to dissipate the mitochondrial proton gradient and cause metabolic inefficiency. We therefore hypothesized that overexpression of UCP3 in skeletal muscle might protect against fat-induced insulin resistance in muscle by conversion of intramyocellular fat into thermal energy. Wild-type mice fed a high-fat diet were markedly insulin resistant, a result of defects in insulin-stimulated glucose uptake in skeletal muscle and hepatic insulin resistance. Insulin resistance in these tissues was associated with reduced insulin-stimulated insulin receptor substrate 1– (IRS-1–) and IRS-2–associated PI3K activity in muscle and liver, respectively. In contrast, UCP3-overexpressing mice were completely protected against fat-induced defects in insulin signaling and action in these tissues. Furthermore, these changes were associated with a lower membrane-to-cytosolic ratio of diacylglycerol and reduced PKCθ activity in whole-body fat–matched UCP3 transgenic mice. These results suggest that increasing mitochondrial uncoupling in skeletal muscle may be an excellent therapeutic target for type 2 diabetes mellitus. PMID:17571165

  15. Catalase overexpression reduces the germination time and increases the pathogenicity of the fungus Metarhizium anisopliae.

    Science.gov (United States)

    Morales Hernandez, Claudia Erika; Padilla Guerrero, Israel Enrique; Gonzalez Hernandez, Gloria Angelica; Salazar Solis, Eduardo; Torres Guzman, Juan Carlos

    2010-07-01

    Catalases and peroxidases are the most important enzymes that degrade hydrogen peroxide into water and oxygen. These enzymes and superoxide dismutase are the first lines of cell defense against reactive oxygen species. Metarhizium anisopliae displays an increase in catalase-peroxidase activity during germination and growth. To determine the importance of catalase during the invasion process of M. anisopliae, we isolated the cat1 gene. cat1 cDNA expression in Escherichia coli and the subsequent purification of the protein confirmed that the cat1 gene codes for a monofunctional catalase. Expression analysis of this gene by RT-PCR from RNA isolated from fungus grown in liquid cultures showed a decrease in the expression level of the cat1 gene during germination and an increase during mycelium growth. The expression of this gene in the fungus during the infection process of the larvae of Plutella xylostella also showed a significant increase during invasive growth. Transgenic strains overexpressing the cat1 gene had twice the catalase activity of the wild-type strain. This increase in catalase activity was accompanied by a higher level of resistance to exogenous hydrogen peroxide and a reduction in the germination time. This improvement was also observed during the infection of P. xylostella larvae. M. anisopliae transgenic strains overexpressing the cat1 gene grew and spread faster in the soft tissue of the insect, reducing the time to death of the insect by 25% and the dose required to kill 50% of the population 14-fold.

  16. YUCCA6 over-expression demonstrates auxin function in delaying leaf senescence in Arabidopsis thaliana

    KAUST Repository

    Kim, Jeong Im

    2011-04-21

    The Arabidopsis thaliana YUCCA family of flavin monooxygenase proteins catalyses a rate-limiting step in de novo auxin biosynthesis. A YUCCA6 activation mutant, yuc6-1D, has been shown to contain an elevated free IAA level and to display typical high-auxin phenotypes. It is reported here that Arabidopsis plants over-expressing YUCCA6, such as the yuc6-1D activation mutant and 35S:YUC6 transgenic plants, displayed dramatic longevity. In addition, plants over-expressing YUCCA6 exhibited classical, delayed dark-induced and hormone-induced senescence in assays using detached rosette leaves. However, plants over-expressing an allele of YUCCA6, that carries mutations in the NADPH cofactor binding site, exhibited neither delayed leaf senescence phenotypes nor phenotypes typical of auxin overproduction. When the level of free IAA was reduced in yuc6-1D by conjugation to lysine, yuc6-1D leaves senesced at a rate similar to the wild-type leaves. Dark-induced senescence in detached leaves was accompanied by a decrease in their free IAA content, by the reduced expression of auxin biosynthesis enzymes such as YUCCA1 and YUCCA6 that increase cellular free IAA levels, and by the increased expression of auxin-conjugating enzymes encoded by the GH3 genes that reduce the cellular free auxin levels. Reduced transcript abundances of SAG12, NAC1, and NAC6 during senescence in yuc6-1D compared with the wild type suggested that auxin delays senescence by directly or indirectly regulating the expression of senescence-associated genes. 2011 The Author(s).

  17. Transgenic overexpression of SUR1 in the heart suppresses sarcolemmal K(ATP).

    Science.gov (United States)

    Flagg, Thomas P; Remedi, Maria Sara; Masia, Ricard; Gomes, Jefferson; McLerie, Meredith; Lopatin, Anatoli N; Nichols, Colin G

    2005-10-01

    The lack of pathological consequences of cardiac ATP-sensitive potassium channel (K(ATP)) channel gene manipulation is in stark contrast to the effect of similar perturbations in the pancreatic beta-cell. Because the pancreatic and cardiac channel share the same pore-forming subunit (Kir6.2), the different effects of genetic manipulation likely reflect, at least in part, the tissue-specific expression of the regulatory subunit (SUR1 in pancreas vs. SUR2A in heart) of the bipartite channel complex. To examine this, we have generated transgenic (TG) mice that overexpress epitope-tagged SUR1 or SUR2A under the transcriptional control of the alpha-myosin heavy chain promoter. Western blot and real time RT-PCR analysis confirm transgene expression in the heart, and variable levels of SUR1 RNA and protein, in 16 viable founder lines. Surprisingly, activation of channels by either pharmacological agents (diazoxide and pinacidil) or metabolic inhibitors (oligomycin and 2-deoxyglucose) reveals a suppression of total K(ATP) conductance in high expressing TG mice. Moreover, K(ATP) channel activity was significantly reduced in excised cardiac patches from TG myocytes that overexpress either SUR1 or SUR2A. Using a recombinant cell system, we show that overexpression of either SUR1 or Kir6.2 suppresses the functional expression of K(ATP) from optimized dimeric SUR1-Kir6.2. Thus, the graded effect of SUR1 expression in the intact heart appears to demonstrate an in vivo requirement for 1:1 expression ratio of Kir6.2 and SURx.

  18. The bone morphogenetic protein antagonist gremlin 1 is overexpressed in human cancers and interacts with YWHAH protein

    Directory of Open Access Journals (Sweden)

    Hur Soo

    2006-03-01

    Full Text Available Abstract Background Basic studies of oncogenesis have demonstrated that either the elevated production of particular oncogene proteins or the occurrence of qualitative abnormalities in oncogenes can contribute to neoplastic cellular transformation. The purpose of our study was to identify an unique gene that shows cancer-associated expression, and characterizes its function related to human carcinogenesis. Methods We used the differential display (DD RT-PCR method using normal cervical, cervical cancer, metastatic cervical tissues, and cervical cancer cell lines to identify genes overexpressed in cervical cancers and identified gremlin 1 which was overexpressed in cervical cancers. We determined expression levels of gremlin 1 using Northern blot analysis and immunohistochemical study in various types of human normal and cancer tissues. To understand the tumorigenesis pathway of identified gremlin 1 protein, we performed a yeast two-hybrid screen, GST pull down assay, and immunoprecipitation to identify gremlin 1 interacting proteins. Results DDRT-PCR analysis revealed that gremlin 1 was overexpressed in uterine cervical cancer. We also identified a human gremlin 1 that was overexpressed in various human tumors including carcinomas of the lung, ovary, kidney, breast, colon, pancreas, and sarcoma. PIG-2-transfected HEK 293 cells exhibited growth stimulation and increased telomerase activity. Gremlin 1 interacted with homo sapiens tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein, eta polypeptide (14-3-3 eta; YWHAH. YWHAH protein binding site for gremlin 1 was located between residues 61–80 and gremlin 1 binding site for YWHAH was found to be located between residues 1 to 67. Conclusion Gremlin 1 may play an oncogenic role especially in carcinomas of the uterine cervix, lung, ovary, kidney, breast, colon, pancreas, and sarcoma. Over-expressed gremlin 1 functions by interaction with YWHAH. Therefore, Gremlin 1 and its binding

  19. Overexpression of the human MNB/DYRK1A gene induces formation of multinucleate cells through overduplication of the centrosome

    Directory of Open Access Journals (Sweden)

    Hiraoka Yasushi

    2003-09-01

    Full Text Available Abstract Background Previously we cloned the human MNB/DYRK1A gene from the "Down syndrome critical region" on chromosome 21. This gene encodes a dual specificity protein kinase that catalyzes its autophosphorylation on serine/threonine and tyrosine residues. But, the functions of the MNB/DYRK1A gene in cellular processes are unknown. Results In this study, we examined HeLa cells transfected with cDNA encoding a green fluorescent protein (GFP-MNB/DYRK1A fusion protein and found 2 patterns of expression: In one group of transfected cells, GFP-MNB/DYRK1A was localized as dots within the nucleus; and in the other group, it was overexpressed and had accumulated all over the nucleus. In the cells overexpressing GFP-MNB/DYRK1A, multinucleation was clearly observed; whereas in those with the nuclear dots, such aberrant nuclei were not found. Furthermore, in the latter cells, essential processes such as mitosis and cytokinesis occurred normally. Multinucleation was dependent on the kinase activity of MNB/DYRK1A, because it was not observed in cells overexpressing kinase activity-negative mutants, GFP-MNB/DYRK1A (K179R and GFP-MNB/DYRK1A (Y310F/Y312F. Immunostaining of GFP-MNB/DYRK1A-overexpressing cells with specific antibodies against α- and γ-tubulin revealed that multiple copies of centrosomes and aberrant multipolar spindles were generated in these cells. Conclusions These results indicate that overexpression of MNB/DYRK1A induces multinucleation in HeLa cells through overduplication of the centrosome during interphase and production of aberrant spindles and missegregation of chromosomes during mitosis.

  20. Changes in the relative inflammatory responses in sheep cells overexpressing of toll-like receptor 4 when stimulated with LPS.

    Directory of Open Access Journals (Sweden)

    Shoulong Deng

    Full Text Available BACKGROUND: Many groups of Gram-negative bacteria cause diseases harmful to sheep. TLR4 is an important Toll-like receptor (TLR which responds to common Gram-negative bacterial infections. Activation of TLR4 leads to the induction of inflammatory responses, which is a linkage between the innate and adaptive immune systems. A vector pTLR4-3S was constructed to overexpress TLR4 gene in sheep. In this study, effects of TLR4 overexpression on inflammation response under LPS stimulated were addressed in vivo and in vitro. METHODOLOGY/PRINCIPAL FINDINGS: Sheep fetal fibroblasts were transfected with expression vector pTLR4-3S. Transgenic sheep were produced by microinjection of the constructed plasmids into fertilized eggs. Fetal fibroblasts, monocyte-macrophage and fibroblasts isolated from the transgenic sheep were stimulated by LPS. After that immunoactive factors (TNF-α, IL-10, IL-6, IL-8, IFN-γ, nitric oxide, phagocytize ability and adhesion were detected. Furthermore, transgenic sheep were intradermal injected of LPS in ear and observed pathological changes by HE strain. Overexpression of TLR4 gene was observed on transgenic cells and individuals. In vitro, TLR4 overexpression transgenic cells secreted Th1 and Th2 inducing cytokines with a strong LPS mediated inflammation response and promoting the secretion of nitric oxide, and then recovered to initial level. The phagocytosis index of monocyte/macrophage in transgenic sheep was higher than that of non-transgenic sheep (P<0.05. In vivo, tissue sections showed that transgenic individuals launched inflammation response more quickly. CONCLUSIONS/SIGNIFICANCE: Overexpression of TLR4 in transgenic sheep enhanced the clearance of invaded microbe through secretion of cytokines, activation of macrophage, oxidation damage and infiltration of neutrophil.

  1. Squalamine and cisplatin block angiogenesis and growth of human ovarian cancer cells with or without HER-2 gene overexpression.

    Science.gov (United States)

    Li, Dan; Williams, Jon I; Pietras, Richard J

    2002-04-25

    Angiogenesis is important for growth and progression of ovarian cancers. Squalamine is a natural antiangiogenic sterol, and its potential role in treatment of ovarian cancers with or without standard cisplatin chemotherapy was assessed. Since HER-2 gene overexpression is associated with cisplatin resistance in vitro and promotion of tumor angiogenesis in vivo, the response of ovarian cancer cells with or without HER-2 gene overexpression to squalamine and cisplatin was evaluated both in tumor xenograft models and in tissue culture. Ovarian cancer cells with or without HER-2 overexpression were grown as subcutaneous xenografts in nude mice. Animals were treated by intraperitoneal injection with control vehicle, cisplatin, squalamine or cisplatin combined with squalamine. At the end of the experiment, tumors were assessed for tumor growth inhibition and for changes in microvessel density and apoptosis. Additional in vitro studies evaluated effects of squalamine on tumor and endothelial cell growth and on signaling pathways in human endothelial cells. Profound growth inhibition was elicited by squalamine alone and by combined treatment with squalamine and cisplatin for both parental and HER-2-overexpressing ovarian tumor xenografts. Immunohistochemical evaluation of tumors revealed decreased microvessel density and increased apoptosis. Although HER-2-overexpressing tumors had more angiogenic and less apoptotic activity than parental cancers, growth of both tumor types was similarly suppressed by treatment with squalamine combined with cisplatin. In in vitro studies, we found that squalamine does not directly affect proliferation of ovarian cells. However, squalamine significantly blocked VEGF-induced activation of MAP kinase and cell proliferation in human vascular endothelial cells. The results suggest that squalamine is anti-angiogenic for ovarian cancer xenografts and appears to enhance cytotoxic effects of cisplatin chemotherapy independent of HER-2 tumor status.

  2. Afatinib and its encapsulated polymeric micelles inhibits HER2-overexpressed colorectal tumor cell growth in vitro and in vivo.

    Science.gov (United States)

    Guan, Siao-Syun; Chang, Jungshan; Cheng, Chun-Chia; Luo, Tsai-Yueh; Ho, Ai-Sheng; Wang, Chia-Chi; Wu, Cheng-Tien; Liu, Shing-Hwa

    2014-07-15

    Colorectal cancer (CRC) is known as a common malignant neoplasm worldwide. The role of EGFR/HER2 in CRC is unclear. Afatinib is an irreversible EGFR/HER2 inhibitor. There were few studies of afatinib on CRC. Here, we investigated the protein levels/expressions of HER2 in sera and tumors from CRC patients and the therapeutic effect of afatinib on HER2-overexpressed CRC in vitro and in vivo. The increased HER2 levels were detected in the collected sera and tumors of patients with CRC. The serological HER2 levels were correlated with the tumor HER2 expressions in patients. Afatinib also inhibited the HER2-positive tumor cell growth and caused apoptosis in HER2-overexpressed human colorectal cancer HCT-15 cells but not in low HER2 expressed human gastric cancer MKN45 cells. In vivo study showed that afatinib reduced tumor growth in HER2-overexpressed xenografts. Moreover, afatinib-encapsulated micelles displayed higher cytotoxic activity in HCT-15 cells and were more effective for tumor growth suppression in HCT-15-induced tumor xenografts than afatinib performance alone. Taken together, these findings suggest that higher serum HER2 levels reflect the higher HER2 contents in tumors of CRC patients, and the improved afatinib-encapsulated micelles possess high therapeutic efficacy in HER2-overexpressed CRC in vitro and in vivo.

  3. The effect of a DNA repair gene on cellular invasiveness: XRCC3 over-expression in breast cancer cells.

    Directory of Open Access Journals (Sweden)

    Veronica L Martinez-Marignac

    Full Text Available Over-expression of DNA repair genes has been associated with resistance to radiation and DNA-damage induced by chemotherapeutic agents such as cisplatin. More recently, based on the analysis of genome expression profiling, it was proposed that over-expression of DNA repair genes enhances the invasive behaviour of tumour cells. In this study we present experimental evidence utilizing functional assays to test this hypothesis. We assessed the effect of the DNA repair proteins known as X-ray complementing protein 3 (XRCC3 and RAD51, to the invasive behavior of the MCF-7 luminal epithelial-like and BT20 basal-like triple negative human breast cancer cell lines. We report that stable or transient over-expression of XRCC3 but not RAD51 increased invasiveness in both cell lines in vitro. Moreover, XRCC3 over-expressing MCF-7 cells also showed a higher tumorigenesis in vivo and this phenotype was associated with increased activity of the metalloproteinase MMP-9 and the expression of known modulators of cell-cell adhesion and metastasis such as CD44, ID-1, DDR1 and TFF1. Our results suggest that in addition to its' role in facilitating repair of DNA damage, XRCC3 affects invasiveness of breast cancer cell lines and the expression of genes associated with cell adhesion and invasion.

  4. Modulation of plasminogen activator inhibitor-1 (PAI-1) by the naphthoquinone shikonin.

    Science.gov (United States)

    Han, Tingting; Zhang, Guangping; Yan, Dong; Yang, Hong; Ma, Tonghui; Ye, Zuguang

    2016-09-01

    Plasminogen activator inhibitor-1 (PAI-1) is a key negative regulator of the fibrinolytic system. Elevated levels of PAI-1 are associated with thrombosis and cardiovascular and metabolic diseases. Inhibition of PAI-1 activity represents a new strategy for antithrombotic and antifibrinolysis therapies. In this study, we systematically investigated the inhibitory effect of shikonin on PAI-1 activity. In the chromogenic substrate-based urokinase (uPA)/PAI-1 assay, we found that shikonin inhibited human PAI-1 activity with IC50 values of 30.68±2.32μM. This result was further confirmed by urokinase-type plasminogen activator (uPA)-mediated clot lysis assay. Mechanistic studies indicated that shikonin directly could bind to PAI-1 and prevent the binding of PAI-1 to uPA in a dose-dependent manner. Shikonin also blocked the formation of PAI-1/uPA complex, as shown by SDS/PAGE analysis. In the mouse arterial thrombosis model, intraperitoneal injection of shikonin at 1mgkg(-1) dose significantly prolonged tail bleeding time from 12.956±4.457min to 26.576±2.443min. It also reduced arterial thrombus weight from 0.01±0.001g to 0.006±0.001g (pPAI-1 that could have become a lead drug the treatment of thrombus and fibrosis.

  5. Overexpression of esterase D in kidney from trisomy 13 fetuses

    Energy Technology Data Exchange (ETDEWEB)

    Loughna, S.; Moore, G. (Institute of Obstetrics and Gynaecology, London (United Kingdom)); Gau, G.; Blunt, S. (Cytogenetics Lab., London (United Kingdom)); Nicolaides, K. (King' s College School of Medicine and Dentistry, London (United Kingdom))

    1993-10-01

    Human trisomy 13 (Patau syndrome) occurs in approximately 1 in 5,000 live births. It is compatible with life, but prolonged survival is rare. Anomalies often involve the urogenital, cardiac, craniofacial, and central nervous systems. It is possible that these abnormalities may be due to the overexpression of developmentally important genes on chromosome 13. The expression of esterase D (localized to chromosome 13q14.11) has been investigated in both muscle and kidney from trisomy 13 fetuses and has been compared with normal age- and sex-matched fetal tissues, by using northern analysis. More than a twofold increase in expression of esterase D was found in the kidney of two trisomy 13 fetuses, with normal levels in a third. Overexpression was not seen in the muscle tissues from these fetuses. 34 refs., 3 figs., 2 tabs.

  6. Overexpression of the riboflavin biosynthetic pathway in Pichia pastoris

    Directory of Open Access Journals (Sweden)

    Mattanovich Diethard

    2008-07-01

    Full Text Available Abstract Background High cell density cultures of Pichia pastoris grown on methanol tend to develop yellow colored supernatants, attributed to the release of free flavins. The potential of P. pastoris for flavin overproduction is therefore given, but not pronounced when the yeast is grown on glucose. The aim of this study is to characterize the relative regulatory impact of each riboflavin synthesis gene. Deeper insight into pathway control and the potential of deregulation is established by overexpression of the single genes as well as a combined deregulation of up to all six riboflavin synthesis genes. Results Overexpression of the first gene of the riboflavin biosynthetic pathway (RIB1 is already sufficient to obtain yellow colonies and the accumulation of riboflavin in the supernatant of shake flask cultures growing on glucose. Sequential deregulation of all the genes, by exchange of their native promoter with the strong and constitutive glyceraldehyde-3-phosphate dehydrogenase promoter (PGAP increases the riboflavin accumulation significantly. Conclusion The regulation of the pathway is distributed over more than one gene. High cell density cultivations of a P. pastoris strain overexpressing all six RIB genes allow the accumulation of 175 mg/L riboflavin in the supernatant. The basis for rational engineering of riboflavin production in P. pastoris has thus been established.

  7. Overexpression of Mafb in podocytes protects against diabetic nephropathy.

    Science.gov (United States)

    Morito, Naoki; Yoh, Keigyou; Ojima, Masami; Okamura, Midori; Nakamura, Megumi; Hamada, Michito; Shimohata, Homare; Moriguchi, Takashi; Yamagata, Kunihiro; Takahashi, Satoru

    2014-11-01

    We previously showed that the transcription factor Mafb is essential for podocyte differentiation and foot process formation. Podocytes are susceptible to injury in diabetes, and this injury leads to progression of diabetic nephropathy. In this study, we generated transgenic mice that overexpress Mafb in podocytes using the nephrin promoter/enhancer. To examine a potential pathogenetic role for Mafb in diabetic nephropathy, Mafb transgenic mice were treated with either streptozotocin or saline solution. Diabetic nephropathy was assessed by renal histology and biochemical analyses of urine and serum. Podocyte-specific overexpression of Mafb had no effect on body weight or blood glucose levels in either diabetic or control mice. Notably, albuminuria and changes in BUN levels and renal histology observed in diabetic wild-type animals were ameliorated in diabetic Mafb transgenic mice. Moreover, hyperglycemia-induced downregulation of Nephrin was mitigated in diabetic Mafb transgenic mice, and reporter assay results suggested that Mafb regulates Nephrin directly. Mafb transgenic glomeruli also overexpressed glutathione peroxidase, an antioxidative stress enzyme, and levels of the oxidative stress marker 8-hydroxydeoxyguanosine decreased in the urine of diabetic Mafb transgenic mice. Finally, Notch2 expression increased in diabetic glomeruli, and this effect was enhanced in diabetic Mafb transgenic glomeruli. These data indicate Mafb has a protective role in diabetic nephropathy through regulation of slit diaphragm proteins, antioxidative enzymes, and Notch pathways in podocytes and suggest that Mafb could be a therapeutic target.

  8. Impact of Adiponectin Overexpression on Allergic Airways Responses in Mice

    Directory of Open Access Journals (Sweden)

    Norah G. Verbout

    2013-01-01

    Full Text Available Obesity is an important risk factor for asthma. Obese individuals have decreased circulating adiponectin, an adipose-derived hormone with anti-inflammatory properties. We hypothesized that transgenic overexpression of adiponectin would attenuate allergic airways inflammation and mucous hyperplasia in mice. To test this hypothesis, we used mice overexpressing adiponectin (Adipo Tg. Adipo Tg mice had marked increases in both serum adiponectin and bronchoalveolar lavage (BAL fluid adiponectin. Both acute and chronic ovalbumin (OVA sensitization and challenge protocols were used. In both protocols, OVA-induced increases in total BAL cells were attenuated in Adipo Tg versus WT mice. In the acute protocol, OVA-induced increases in several IL-13 dependent genes were attenuated in Adipo Tg versus WT mice, even though IL-13 per se was not affected. With chronic exposure, though OVA-induced increases in goblet cells numbers per millimeter of basement membrane were greater in Adipo Tg versus WT mice, mRNA abundance of mucous genes in lungs was not different. Also, adiponectin overexpression did not induce M2 polarization in alveolar macrophages. Our results indicate that adiponectin protects against allergen-induced inflammatory cell recruitment to the airspaces, but not development of goblet cell hyperplasia.

  9. Dentin sialoprotein and dentin phosphoprotein overexpression during amelogenesis.

    Science.gov (United States)

    Paine, Michael L; Luo, Wen; Wang, Hong-Jun; Bringas, Pablo; Ngan, Amanda Y W; Miklus, Vetea G; Zhu, Dan-Hong; MacDougall, Mary; White, Shane N; Snead, Malcolm L

    2005-09-09

    The gene for dentin sialophosphoprotein produces a single protein that is post-translationally modified to generate two distinct extracellular proteins: dentin sialoprotein and dentin phosphoprotein. In teeth, dentin sialophosphoprotein is expressed primarily by odontoblast cells, but is also transiently expressed by presecretory ameloblasts. Because of this expression profile it appears that dentin sialophosphoprotein contributes to the early events of amelogenesis, and in particular to those events that result in the formation of the dentino-enamel junction and the adjacent "aprismatic" enamel. Using a transgenic animal approach we have extended dentin sialoprotein or dentin phosphoprotein expression throughout the developmental stages of amelogenesis. Overexpression of dentin sialoprotein results in an increased rate of enamel mineralization, however, the enamel morphology is not significantly altered. In wild-type animals, the inclusion of dentin sialoprotein in the forming aprismatic enamel may account for its increased hardness properties, when compared with bulk enamel. In contrast, the overexpression of dentin phosphoprotein creates "pitted" and "chalky" enamel of non-uniform thickness that is more prone to wear. Disruptions to the prismatic enamel structure are also a characteristic of the dentin phosphoprotein overexpressing animals. These data support the previous suggestion that dentin sialoprotein and dentin phosphoprotein have distinct functions related to tooth formation, and that the dentino-enamel junction should be viewed as a unique transition zone between enamel and the underlying dentin. These results support the notion that the dentin proteins expressed by presecretory ameloblasts contribute to the unique properties of the dentino-enamel junction.

  10. Pancreatic beta-cell lipotoxicity induced by overexpression of hormone-sensitive lipase

    DEFF Research Database (Denmark)

    Winzell, Maria Sörhede; Svensson, Håkan; Enerbäck, Sven;

    2003-01-01

    Lipid perturbations associated with triglyceride overstorage in beta-cells impair insulin secretion, a process termed lipotoxicity. To assess the role of hormone-sensitive lipase, which is expressed and enzymatically active in beta-cells, in the development of lipotoxicity, we generated transgenic...... mice overexpressing hormone-sensitive lipase specifically in beta-cells. Transgenic mice developed glucose intolerance and severely blunted glucose-stimulated insulin secretion when challenged with a high-fat diet. As expected, both lipase activity and forskolin-stimulated lipolysis was increased...... results highlight the importance of mobilization of the islet triglyceride pool in the development of beta-cell lipotoxicity. We propose that hormone-sensitive lipase is involved in mediating beta-cell lipotoxicity by providing ligands for peroxisome proliferator-activated receptors and other lipid...

  11. Genome wide transcription profiling of the effects of overexpression of Spc1 and its kinase dead mutant in Schizosaccharomyces pombe

    Directory of Open Access Journals (Sweden)

    Madhurima Paul

    2015-12-01

    Full Text Available The Mitogen Activated Protein Kinase Spc1 (p38 homolog is a major player in stress responses of the unicellular fission yeast Schizosaccharomyces pombe. This pathway is therefore also known as the SAPK or Stress Activated Protein Kinase pathway. Spc1 is a known activator of transcription factors that control gene expression in response to extracellular stimuli and is also known to interact with the translation machinery [1–8]. Spc1 has also been implicated in cell cycle regulation and meiosis in S. pombe [1,2,9,10]. Given its documented role in modulating gene expression, we performed a microarray based identification of genes whose expression in unperturbed cells (absence of stress stimuli is dependent on Spc1. For this we overexpressed Spc1 in S. pombe. Additionally we also overexpressed Spc1K49R (a kinase dead mutant of Spc1 to understand the contribution of Spc1's kinase activity towards the observed gene expression changes. The microarray data are available at NCBI's Gene Expression Omnibus (GEO Series (accession number GSE73618. Here we report the annotation of the genes whose expression get altered by Spc1/Spc1K49R overexpression and also provide details related to sample processing and statistical analysis of our microarray data.

  12. RNF13: a novel RING-type ubiquitin ligase over-expressed in pancreatic cancer

    Institute of Scientific and Technical Information of China (English)

    Qiang Zhang; Yunxiao Meng; Lei Zhang; Jie Chen; Dahai Zhu

    2009-01-01

    Protein ubiquitination by E3 ubiquitin ligases plays an important role in cancer development. In this study, we provide experimental evidence that a RING-finger-containing protein RNF13 is an ER/Golgi membrane-associated E3 ubiquitin ligase and its RING finger domain is required for the ubiquitin iigase activity, lmmunohistochemical analysis of pancreatic ductal adenocarcinoma (PDAC) and paracancerous normal tissues from 72 patients documented RNF13 over-expression in 30 tumor samples (41.7%, 30/72), and its expression was significantly associated with histological grading (P= 0.024). In addition, RNFI3 was detected in precancerous lesions: tubular complexes in chronic pancreatitis (CP) and pancreatic intraepithelial neoplasia (PanlN) (79.3%, 23/29 and 62.8%, 22/35, respectively). Moreover, RNF13 staining was significantly correlated with Tenascin-C expression (P = 0.004) in PDAC samples, further supporting the role of RNF13 in cancer progression. Over-expression of wild type but not RING domain-mutant RNF13 in pancreatic MiaPaca-2 cancer cells increased invasive potential and gelatinolytic activity by matrix metalloproteinase-9. Taken together, these findings reveal that RNF13 is a novel E3 ubiquitin ligase involved in pancreatic carcinogenesis; ubiqui-tin-mediated modification of proteins by RNF13 may participate in pancreatic cancer development.

  13. FOX-2 dependent splicing of ataxin-2 transcript is affected by ataxin-1 overexpression.

    Directory of Open Access Journals (Sweden)

    Franziska Welzel

    Full Text Available Alternative splicing is a fundamental posttranscriptional mechanism for controlling gene expression, and splicing defects have been linked to various human disorders. The splicing factor FOX-2 is part of a main protein interaction hub in a network related to human inherited ataxias, however, its impact remains to be elucidated. Here, we focused on the reported interaction between FOX-2 and ataxin-1, the disease-causing protein in spinocerebellar ataxia type 1. In this line, we further evaluated this interaction by yeast-2-hybrid analyses and co-immunoprecipitation experiments in mammalian cells. Interestingly, we discovered that FOX-2 localization and splicing activity is affected in the presence of nuclear ataxin-1 inclusions. Moreover, we observed that FOX-2 directly interacts with ataxin-2, a protein modulating spinocerebellar ataxia type 1 pathogenesis. Finally, we provide evidence that splicing of pre-mRNA of ataxin-2 depends on FOX-2 activity, since reduction of FOX-2 levels led to increased skipping of exon 18 in ataxin-2 transcripts. Most striking, we observed that ataxin-1 overexpression has an effect on this splicing event as well. Thus, our results demonstrate that FOX-2 is involved in splicing of ataxin-2 transcripts and that this splicing event is altered by overexpression of ataxin-1.

  14. Germinal center reentries of BCL2-overexpressing B cells drive follicular lymphoma progression

    Science.gov (United States)

    Sungalee, Stéphanie; Mamessier, Emilie; Morgado, Ester; Grégoire, Emilie; Brohawn, Philip Z.; Morehouse, Christopher A.; Jouve, Nathalie; Monvoisin, Céline; Menard, Cédric; Debroas, Guilhaume; Faroudi, Mustapha; Mechin, Violaine; Navarro, Jean-Marc; Drevet, Charlotte; Eberle, Franziska C.; Chasson, Lionel; Baudimont, Fannie; Mancini, Stéphane J.; Tellier, Julie; Picquenot, Jean-Michel; Kelly, Rachel; Vineis, Paolo; Ruminy, Philippe; Chetaille, Bruno; Jaffe, Elaine S.; Schiff, Claudine; Hardwigsen, Jean; Tice, David A.; Higgs, Brandon W.; Tarte, Karin; Nadel, Bertrand; Roulland, Sandrine

    2014-01-01

    It has recently been demonstrated that memory B cells can reenter and reengage germinal center (GC) reactions, opening the possibility that multi-hit lymphomagenesis gradually occurs throughout life during successive immunological challenges. Here, we investigated this scenario in follicular lymphoma (FL), an indolent GC-derived malignancy. We developed a mouse model that recapitulates the FL hallmark t(14;18) translocation, which results in constitutive activation of antiapoptotic protein B cell lymphoma 2 (BCL2) in a subset of B cells, and applied a combination of molecular and immunofluorescence approaches to track normal and t(14;18)+ memory B cells in human and BCL2-overexpressing B cells in murine lymphoid tissues. BCL2-overexpressing B cells required multiple GC transits before acquiring FL-associated developmental arrest and presenting as GC B cells with constitutive activation–induced cytidine deaminase (AID) mutator activity. Moreover, multiple reentries into the GC were necessary for the progression to advanced precursor stages of FL. Together, our results demonstrate that protracted subversion of immune dynamics contributes to early dissemination and progression of t(14;18)+ precursors and shapes the systemic presentation of FL patients. PMID:25384217

  15. Overexpression of carboxylesterase contributes to the attenuation of cyanotoxin microcystin-LR toxicity.

    Science.gov (United States)

    Takumi, Shota; Shimono, Tai; Ikema, Satoshi; Hotta, Yuki; Chigwechokha, Petros K; Shiozaki, Kazuhiro; Sugiyama, Yasumasa; Hashimoto, Mitsuru; Furukawa, Tatsuhiko; Komatsu, Masaharu

    2017-04-01

    Microcystin-LR is a hepatotoxin produced by several cyanobacteria. Its toxicity is mainly due to a inhibition of protein phosphatase, PP1 and PP2A. Previously, we used a cell line stably expressing uptake transporter for microcystin-LR, OATP1B3 (HEK293-OATP1B3 cells). In this study, to determine whether overexpression of carboxylesterase (CES), which degrades ester-group and amide-group, attenuates the cytotoxicity of microcystin-LR, we generated the HEK293-OATP1B3/CES2 double-transfected cells. HEK293-OATP1B3/CES2 cells showed high hydrolysis activity of p-nitrophenyl acetate (PNPA), which is an authentic substrate for esterase. CES activity in HEK293-OATP1B3/CES2 cells was approximately 3-fold higher than that in the HEK293-OATP1B3 cells. HEK293-OATP1B3/CES2 cells (IC50: 25.4±7.7nM) showed approximately 2.1-fold resistance to microcystin-LR than HEK293-OATP1B3 cells (IC50: 12.0±1.5nM). Moreover, the CES inhibition assay and microcystin-agarose pull down assay showed the possibility of the interaction between CES2 and microcystin-LR. Our results indicated that the overexpression of CES2 attenuates the cytotoxicity of microcystin-LR via interaction with microcystin-LR.

  16. Large-scale overexpression and purification of ADARs from Saccharomyces cerevisiae for biophysical and biochemical studies.

    Science.gov (United States)

    Macbeth, Mark R; Bass, Brenda L

    2007-01-01

    Many biochemical and biophysical analyses of enzymes require quantities of protein that are difficult to obtain from expression in an endogenous system. To further complicate matters, native adenosine deaminases that act on RNA (ADARs) are expressed at very low levels, and overexpression of active protein has been unsuccessful in common bacterial systems. Here we describe the plasmid construction, expression, and purification procedures for ADARs overexpressed in the yeast Saccharomyces cerevisiae. ADAR expression is controlled by the Gal promoter, which allows for rapid induction of transcription when the yeast are grown in media containing galactose. The ADAR is translated with an N-terminal histidine tag that is cleaved by the tobacco etch virus protease, generating one nonnative glycine residue at the N-terminus of the ADAR protein. ADARs expressed using this system can be purified to homogeneity, are highly active in deaminating RNA, and are produced in quantities (from 3 to 10mg of pure protein per liter of yeast culture) that are sufficient for most biophysical studies.

  17. Overexpression of Citrus junos mitochondrial citrate synthase gene in Nicotiana benthamiana confers aluminum tolerance.

    Science.gov (United States)

    Deng, Wei; Luo, Keming; Li, Zhengguo; Yang, Yingwu; Hu, Nan; Wu, Yu

    2009-07-01

    Aluminum (Al) toxicity is one of the major factors that limit plant growth in acid soils. Al-induced release of organic acids into rhizosphere from the root apex has been identified as a major Al-tolerance mechanism in many plant species. In this study, Al tolerance of Yuzu (Citrus Junos Sieb. ex Tanaka) was tested on the basis of root elongation and the results demonstrated that Yuzu was Al tolerant compared with other plant species. Exposure to Al triggered the exudation of citrate from the Yuzu root. Thus, the mechanism of Al tolerance in Yuzu involved an Al-inducible increase in citrate release. Aluminum also elicited an increase of citrate content and increased the expression level of mitochondrial citrate synthase (CjCS) gene and enzyme activity in Yuzu. The CjCS gene was cloned from Yuzu and overexpressed in Nicotiana benthamiana using Agrobacterium tumefaciens-mediated methods. Increased expression level of the CjCS gene and enhanced enzyme activity were observed in transgenic plants compared with the wild-type plants. Root growth experiments showed that transgenic plants have enhanced levels of Al tolerance. The transgenic Nicotiana plants showed increased levels of citrate in roots compared to wild-type plants. The exudation of citrate from roots of the transgenic plants significantly increased when exposed to Al. The results with transgenic plants suggest that overexpression of mitochondrial CS can be a useful tool to achieve Al tolerance.

  18. Neurogenic role of the depolarizing chloride gradient revealed by global overexpression of KCC2 from the onset of development.

    Science.gov (United States)

    Reynolds, Annie; Brustein, Edna; Liao, Meijiang; Mercado, Adriana; Babilonia, Elisa; Mount, David B; Drapeau, Pierre

    2008-02-13

    GABA- and glycine-induced depolarization is thought to provide important developmental signals, but the role of the underlying chloride gradient has not been examined from the onset of development. We therefore overexpressed globally the potassium-chloride cotransporter 2 (KCC2) in newly fertilized zebrafish embryos to reverse the chloride gradient. This rendered glycine hyperpolarizing in all neurons, tested at the time that motor behaviors (but not native KCC2) first appear. KCC2 overexpression resulted in fewer mature spontaneously active spinal neurons, more immature silent neurons, and disrupted motor activity. We observed fewer motoneurons and interneurons, a reduction in the elaboration of axonal tracts, and smaller brains and spinal cords. However, we observed no increased apoptosis and a normal complement of sensory neurons, glia, and progenitors. These results suggest that chloride-mediated excitation plays a crucial role in promoting neurogenesis from the earliest stages of embryonic development.

  19. [Community vegetable gardens as a health promotion activity: an experience in Primary Healthcare Units].

    Science.gov (United States)

    Costa, Christiane Gasparini Araújo; Garcia, Mariana Tarricone; Ribeiro, Silvana Maria; Salandini, Marcia Fernanda de Sousa; Bógus, Cláudia Maria

    2015-10-01

    Urban and peri-urban agriculture (UPA) is being practiced in different settings, contributing to the improvement of health in communities and healthier environments. In order to identify the meanings and implications of the practice of UPA in Primary Healthcare Units (PHU) as an activity of health promotion (HP), and to what extent its therapeutic dimension characterizes it as an activity aligned with complementary and integrative practices (CIP), a qualitative cross-sectional study was performed in Embu das Artes, State of São Paulo. From the analysis, the following main themes arose: health concept, health outcomes, the return to traditional practices and habits and the reorientation of health services. It was possible to identify the close link between the cultivation of vegetable gardens and HP guidelines and fields of action, such as creating healthier environments, boosting community actions, developing personal skills, stimulating autonomy and empowerment and demands for the reorientation of services. The garden activities, set up in PHU areas, proved to be an implementation strategy of CIP. The conclusion reached is that vegetable gardening activities in community gardens are seen to be health promotion practices that integrate key elements of CIP.

  20. Astrocyte-specific overexpressed gene signatures in response to methamphetamine exposure in vitro

    KAUST Repository

    Bortell, Nikki

    2017-03-09

    BackgroundAstrocyte activation is one of the earliest findings in the brain of methamphetamine (Meth) abusers. Our goal in this study was to identify the characteristics of the astrocytic acute response to the drug, which may be critical in pathogenic outcomes secondary to the use.MethodsWe developed an integrated analysis of gene expression data to study the acute gene changes caused by the direct exposure to Meth treatment of astrocytes in vitro, and to better understand how astrocytes respond, what are the early molecular markers associated with this response. We examined the literature in search of similar changes in gene signatures that are found in central nervous system disorders.ResultsWe identified overexpressed gene networks represented by genes of an inflammatory and immune nature and that are implicated in neuroactive ligand-receptor interactions. The overexpressed networks are linked to molecules that were highly upregulated in astrocytes by all doses of methamphetamine tested and that could play a role in the central nervous system. The strongest overexpressed signatures were the upregulation of MAP2K5, GPR65, and CXCL5, and the gene networks individually associated with these molecules. Pathway analysis revealed that these networks are involved both in neuroprotection and in neuropathology. We have validated several targets associated to these genes.ConclusionsGene signatures for the astrocytic response to Meth were identified among the upregulated gene pool, using an in vitro system. The identified markers may participate in dysfunctions of the central nervous system but could also provide acute protection to the drug exposure. Further in vivo studies are necessary to establish the role of these gene networks in drug abuse pathogenesis.

  1. Muscle-specific growth hormone receptor (GHR) overexpression induces hyperplasia but not hypertrophy in transgenic zebrafish.

    Science.gov (United States)

    Figueiredo, Marcio Azevedo; Mareco, Edson A; Silva, Maeli Dal Pai; Marins, Luis Fernando

    2012-06-01

    Even though growth hormone (GH) transgenesis has demonstrated potential for improved growth of commercially important species, the hormone excess may result in undesired collateral effects. In this context, the aim of this work was to develop a new model of transgenic zebrafish (Danio rerio) characterized by a muscle-specific overexpression of the GH receptor (GHR) gene, evaluating the effect of transgenesis on growth, muscle structure and expression of growth-related genes. In on line of transgenic zebrafish overexpressing GHR in skeletal muscle, no significant difference in total weight in comparison to non-transgenics was observed. This can be explained by a significant reduction in expression of somatotrophic axis-related genes, in special insulin-like growth factor I (IGF-I). In the same sense, a significant increase in expression of the suppressors of cytokine signaling 1 and 3 (SOCS) was encountered in transgenics. Surprisingly, expression of genes coding for the main myogenic regulatory factors (MRFs) was higher in transgenic than non-transgenic zebrafish. Genes coding for muscle proteins did not follow the MRFs profile, showing a significant decrease in their expression. These results were corroborated by the histological analysis, where a hyperplasic muscle growth was observed in transgenics. In conclusion, our results demonstrated that GHR overexpression does not induce hypertrophic muscle growth in transgenic zebrafish probably because of SOCS impairment of the GHR/IGF-I pathway, culminating in IGF-I and muscle proteins decrease. Therefore, it seems that hypertrophy and hyperplasia follow two different routes for entire muscle growth, both of them triggered by GHR activation, but regulated by different mechanisms.

  2. CaMKIId overexpression in hypertrophy and heart failure: cellular consequences for excitation-contraction coupling

    Directory of Open Access Journals (Sweden)

    Maier L.S.

    2005-01-01

    Full Text Available Ca/calmodulin-dependent protein kinase IIdelta (CaMKIIdelta is the predominant isoform in the heart. During excitation-contraction coupling (ECC CaMKII phosphorylates several Ca-handling proteins including ryanodine receptors (RyR, phospholamban, and L-type Ca channels. CaMKII expression and activity have been shown to correlate positively with impaired ejection fraction in the myocardium of patients with heart failure and CaMKII has been proposed to be a possible compensatory mechanism to keep hearts from complete failure. However, in addition to these acute effects on ECC, CaMKII was shown to be involved in hypertrophic signaling, termed excitation-transcription coupling (ETC. Thus, animal models have shown that overexpression of nuclear isoform CaMKIIdeltaB can induce myocyte hypertrophy. Recent study from our laboratory has suggested that transgenic overexpression of the cytosolic isoform CaMKIIdeltaC in mice causes severe heart failure with altered intracellular Ca handling and protein expression leading to reduced sarcoplasmic reticulum (SR Ca content. Interestingly, the frequency of diastolic spontaneous SR Ca release events (or opening of RyR was greatly enhanced, demonstrating increased diastolic SR Ca leak. This was attributed to increased CaMKII-dependent RyR phosphorylation, resulting in increased and prolonged openings of RyR since Ca spark frequency could be reduced back to normal levels by CaMKII inhibition. This review focuses on acute and chronic effects of CaMKII in ECC and ETC. In summary, CaMKII overexpression can lead to heart failure and CaMKII-dependent RyR hyperphosphorylation seems to be a novel and important mechanism in ECC due to SR Ca leak which may be important in the pathogenesis of heart failure.

  3. FHL1 reduces dystrophy in transgenic mice overexpressing FSHD muscular dystrophy region gene 1 (FRG1.

    Directory of Open Access Journals (Sweden)

    Sandra J Feeney

    Full Text Available Facioscapulohumeral muscular dystrophy (FSHD is an autosomal-dominant disease with no effective treatment. The genetic cause of FSHD is complex and the primary pathogenic insult underlying the muscle disease is unknown. Several disease candidate genes have been proposed including DUX4 and FRG1. Expression analysis studies of FSHD report the deregulation of genes which mediate myoblast differentiation and fusion. Transgenic mice overexpressing FRG1 recapitulate the FSHD muscular dystrophy phenotype. Our current study selectively examines how increased expression of FRG1 may contribute to myoblast differentiation defects. We generated stable C2C12 cell lines overexpressing FRG1, which exhibited a myoblast fusion defect upon differentiation. To determine if myoblast fusion defects contribute to the FRG1 mouse dystrophic phenotype, this strain was crossed with skeletal muscle specific FHL1-transgenic mice. We previously reported that FHL1 promotes myoblast fusion in vitro and FHL1-transgenic mice develop skeletal muscle hypertrophy. In the current study, FRG1 mice overexpressing FHL1 showed an improvement in the dystrophic phenotype, including a reduced spinal kyphosis, increased muscle mass and myofiber size, and decreased muscle fibrosis. FHL1 expression in FRG1 mice, did not alter satellite cell number or activation, but enhanced myoblast fusion. Primary myoblasts isolated from FRG1 mice showed a myoblast fusion defect that was rescued by FHL1 expression. Therefore, increased FRG1 expression may contribute to a muscular dystrophy phenotype resembling FSHD by impairing myoblast fusion, a defect that can be rescued by enhanced myoblast fusion via expression of FHL1.

  4. Bacterial lipoprotein-induced tolerance is reversed by overexpression of IRAK-1.

    LENUS (Irish Health Repository)

    Li, Chong Hui

    2012-03-01

    Tolerance to bacterial cell wall components including bacterial lipoprotein (BLP) represents an essential regulatory mechanism during bacterial infection. Reduced Toll-like receptor 2 (TLR2) and IL-1 receptor-associated kinase 1 (IRAK-1) expression is a characteristic of the downregulated TLR signaling pathway observed in BLP-tolerised cells. In this study, we attempted to clarify whether TLR2 and\\/or IRAK-1 are the key molecules responsible for BLP-induced tolerance. Transfection of HEK293 cells and THP-1 cells with the plasmid encoding TLR2 affected neither BLP tolerisation-induced NF-κB deactivation nor BLP tolerisation-attenuated pro-inflammatory cytokine tumor necrosis factor alpha (TNF-α) production, indicating that BLP tolerance develops despite overexpression of TLR2 in these cells. In contrast, overexpression of IRAK-1 reversed BLP-induced tolerance, as transfection of IRAK-1 expressing vector resulted in a dose-dependent NF-κB activation and TNF-α release in BLP-tolerised cells. Furthermore, BLP-tolerised cells exhibited markedly repressed NF-κB p65 phosphorylation and impaired binding of p65 to several pro-inflammatory cytokine gene promoters including TNF-α and interleukin-6 (IL-6). Overexpression of IRAK-1 restored the nuclear transactivation of p65 at both TNF-α and IL-6 promoters. These results indicate a crucial role for IRAK-1 in BLP-induced tolerance, and suggest IRAK-1 as a potential target for manipulation of the TLR-mediated inflammatory response during microbial sepsis.

  5. Overexpression of adenosine A2A receptors in rats: effects on depression, locomotion and anxiety

    Directory of Open Access Journals (Sweden)

    Joana E Coelho

    2014-06-01

    Full Text Available Adenosine A2A receptors (A2AR are a sub-type of receptors enriched in basal ganglia, activated by the neuromodulator adenosine, which interact with dopamine D2 receptors. Although this reciprocal antagonistic interaction is well established in motor function, the outcome in dopamine-related behaviors remains uncertain, in particular in depression and anxiety. We have demonstrated an upsurge of A2AR associated to aging and chronic stress. Furthermore, Alzheimer’s disease patients present A2AR accumulation in cortical areas together with depressive signs. We now tested the impact of overexpressing A2AR in forebrain neurons on dopamine related behavior, namely depression. Adult male rats overexpressing human A2AR under the control of CaMKII promoter [Tg(CaMKII-hA2AR] and aged-matched wild-types (WT of the same strain (Sprague-Dawley were studied. The forced swimming test (FST, sucrose preference test (SPT and the open-field test (OFT were performed to evaluate behavioral despair, anhedonia, locomotion and anxiety. Tg(CaMKII-hA2AR animals spent more time floating and less time swimming in the FST and presented a decreased sucrose preference at 48h in the SPT. They also covered higher distances in the OFT and spent more time in the central zone than the WT. The results indicate that Tg(CaMKII-hA2AR rats exhibit depressive-like behavior, hyperlocomotion and altered exploratory behavior. This A2AR overexpression may explain the depressive signs found in aging, chronic stress and Alzheimer’s disease.

  6. Over-expression of ST3Gal-I promotes mammary tumorigenesis.

    Science.gov (United States)

    Picco, Gianfranco; Julien, Sylvain; Brockhausen, Inka; Beatson, Richard; Antonopoulos, Aristotelis; Haslam, Stuart; Mandel, Ulla; Dell, Anne; Pinder, Sarah; Taylor-Papadimitriou, Joyce; Burchell, Joy

    2010-10-01

    Changes in glycosylation are common in malignancy, and as almost all surface proteins are glycosylated, this can dramatically affect the behavior of tumor cells. In breast carcinomas, the O-linked glycans are frequently truncated, often as a result of premature sialylation. The sialyltransferase ST3Gal-I adds sialic acid to the galactose residue of core 1 (Galbeta1,3GalNAc) O-glycans and this enzyme is over-expressed in breast cancer resulting in the expression of sialylated core 1 glycans. In order to study the role of ST3Gal-I in mammary tumor development, we developed transgenic mice that over-express the sialyltransferase under the control of the human membrane-bound mucin 1 promoter. These mice were then crossed with PyMT mice that spontaneously develop mammary tumors. As expected, ST3Gal-I transgenic mice showed increased activity and expression of the enzyme in the pregnant and lactating mammary glands, the stomach, lungs and intestine. Although no obvious defects were observed in the fully developed mammary gland, when these mice were crossed with PyMT mice, a highly significant decrease in tumor latency was observed compared to the PyMT mice on an identical background. These results indicate that ST3Gal-I is acting as a tumor promoter in this model of breast cancer. This, we believe, is the first demonstration that over-expression of a glycosyltransferase involved in mucin-type O-linked glycosylation can promote tumorigenesis.

  7. Overexpression of glycerol-3-phosphate acyltransferase gene improves chilling tolerance in tomato.

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    Sui, Na; Li, Meng; Zhao, Shi-Jie; Li, Feng; Liang, Hui; Meng, Qing-Wei

    2007-10-01

    A tomato (Lycopersicon esculentum Mill.) glycerol-3-phosphate acyltransferase gene (LeGPAT) was isolated. The deduced amino acid sequence revealed that LeGPAT contained four acyltransferase domains, showing high identities with GPAT in other plant species. A GFP fusion protein of LeGPAT was targeted to chloroplast in cowpea mesophyll protoplast. RNA gel blot showed that the mRNA accumulation of LeGPAT in the wild type (WT) was induced by chilling temperature. Higher expression levels were observed when tomato leaves were exposed to 4 degrees C for 4 h. RNA gel and western blot analysis confirmed that the sense gene LeGPAT was transferred into the tomato genome and overexpressed under the control of 35S-CaMV. Although tomato is classified as a chilling-sensitive plant, LeGPAT exhibited selectivity to 18:1 over 16:0. Overexpression of LeGPAT increased total activity of LeGPAT and cis-unsaturated fatty acids in PG in thylakoid membrane. Chilling treatment induced less ion leakage from the transgenic plants than from the WT. The photosynthetic rate and the maximal photochemical efficiency of PS II (Fv/Fm) in transgenic plants decreased more slowly during chilling stress and recovered faster than in WT under optimal conditions. The oxidizable P700 in both WT and transgenic plants decreased obviously at chilling temperature under low irradiance, but the oxidizable P700 recovered faster in transgenic plants than in the WT. These results indicate that overexpression of LeGPAT increased the levels of PG cis-unsaturated fatty acids in thylakoid membrane, which was beneficial for the recovery of chilling-induced PS I photoinhibition in tomato.

  8. Overexpression of Snail in retinal pigment epithelial triggered epithelial–mesenchymal transition

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    Li, Hui; Li, Min; Xu, Ding; Zhao, Chun; Liu, Guodong; Wang, Fang, E-mail: milwang_122@msn.com

    2014-03-28

    Highlights: • First reported overexpression of Snail in RPE cells could directly trigger EMT. • Further confirmed the regulator role of Snail in RPE cells EMT in vitro. • Snail may be a potential therapeutic target to prevent the fibrosis of PVR. - Abstract: Snail transcription factor has been implicated as an important regulator in epithelial–mesenchymal transition (EMT) during tumourigenesis and fibrogenesis. Our previous work showed that Snail transcription factor was activated in transforming growth factor β1 (TGF-β1) induced EMT in retinal pigment epithelial (RPE) cells and may contribute to the development of retinal fibrotic disease such as proliferative vitreoretinopathy (PVR). However, whether Snail alone has a direct role on retinal pigment epithelial–mesenchymal transition has not been investigated. Here, we analyzed the capacity of Snail to drive EMT in human RPE cells. A vector encoding Snail gene or an empty vector were transfected into human RPE cell lines ARPE-19 respectively. Snail overexpression in ARPE-19 cells resulted in EMT, which was characterized by the expected phenotypic transition from a typical epithelial morphology to mesenchymal spindle-shaped. The expression of epithelial markers E-cadherin and Zona occludin-1 (ZO-1) were down-regulated, whereas mesenchymal markers a-smooth muscle actin (a-SMA) and fibronectin were up-regulated in Snail expression vector transfected cells. In addition, ectopic expression of Snail significantly enhanced ARPE-19 cell motility and migration. The present data suggest that overexpression of Snail in ARPE-19 cells could directly trigger EMT. These results may provide novel insight into understanding the regulator role of Snail in the development of retinal pigment epithelial–mesenchymal transition.

  9. Small heterodimer partner overexpression partially protects against liver tumor development in farnesoid X receptor knockout mice

    Energy Technology Data Exchange (ETDEWEB)

    Li, Guodong [Department of Surgical Oncology, Cancer Treatment Center, The Fourth Affiliated Hospital of Harbin Medical University, Harbin (China); Kong, Bo [Department of Pharmacology and Toxicology, School of Pharmacy, Rutgers University, Piscataway, NJ (United States); Zhu, Yan [Department of General Surgery, Xuanwu Hospital, Capital Medical University, Beijing (China); Zhan, Le [Department of Pharmacology and Toxicology, School of Pharmacy, Rutgers University, Piscataway, NJ (United States); Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, KS (United States); Williams, Jessica A. [Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, KS (United States); Tawfik, Ossama [Department of Pathology and Laboratory Medicine, University of Kansas Medical Center, Kansas City, KS (United States); Kassel, Karen M. [Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, KS (United States); Luyendyk, James P. [Pathobiology and Diagnostic Investigation, Michigan State University, East Lansing, MI (United States); Wang, Li [Department of Medicine, Huntsman Cancer Institute, University of Utah School of Medicine, Salt Lake City, UT (United States); Guo, Grace L., E-mail: guo@eohsi.rutgers.edu [Department of Pharmacology and Toxicology, School of Pharmacy, Rutgers University, Piscataway, NJ (United States)

    2013-10-15

    Farnesoid X receptor (FXR, Nr1h4) and small heterodimer partner (SHP, Nr0b2) are nuclear receptors that are critical to liver homeostasis. Induction of SHP serves as a major mechanism of FXR in suppressing gene expression. Both FXR{sup −/−} and SHP{sup −/−} mice develop spontaneous hepatocellular carcinoma (HCC). SHP is one of the most strongly induced genes by FXR in the liver and is a tumor suppressor, therefore, we hypothesized that deficiency of SHP contributes to HCC development in the livers of FXR{sup −/−} mice and therefore, increased SHP expression in FXR{sup −/−} mice reduces liver tumorigenesis. To test this hypothesis, we generated FXR{sup −/−} mice with overexpression of SHP in hepatocytes (FXR{sup −/−}/SHP{sup Tg}) and determined the contribution of SHP in HCC development in FXR{sup −/−} mice. Hepatocyte-specific SHP overexpression did not affect liver tumor incidence or size in FXR{sup −/−} mice. However, SHP overexpression led to a lower grade of dysplasia, reduced indicator cell proliferation and increased apoptosis. All tumor-bearing mice had increased serum bile acid levels and IL-6 levels, which was associated with activation of hepatic STAT3. In conclusion, SHP partially protects FXR{sup −/−} mice from HCC formation by reducing tumor malignancy. However, disrupted bile acid homeostasis by FXR deficiency leads to inflammation and injury, which ultimately results in uncontrolled cell proliferation and tumorigenesis in the liver. - Highlights: • SHP does not prevent HCC incidence nor size in FXR KO mice but reduces malignancy. • Increased SHP promotes apoptosis. • Bile acids and inflammation maybe critical for HCC formation with FXR deficiency.

  10. WISP1 overexpression promotes proliferation and migration of human vascular smooth muscle cells via AKT signaling pathway.

    Science.gov (United States)

    Lu, Shun; Liu, Hao; Lu, Lihe; Wan, Heng; Lin, Zhiqi; Qian, Kai; Yao, Xingxing; Chen, Qing; Liu, Wenjun; Yan, Jianyun; Liu, Zhengjun

    2016-10-05

    Proliferation and migration of vascular smooth muscle cells (VSMCs) play crucial roles in the development of vascular restenosis. Our previous study showed that CCN4, namely Wnt1 inducible signaling pathway protein 1 (WISP1), significantly promotes proliferation and migration of rat VSMCs, but its mechanism remains unclear. This study aims to investigate whether and how WISP1 stimulates proliferation and migration of human VSMCs. Western blot analysis showed that FBS treatment increased WISP1 protein levels in human VSMCs in a dose-dependent manner. Overexpression of WISP1 using adenovirus encoding WISP1 (AD-WISP1) significantly increased proliferation rate of human VSMCs by 2.98-fold compared with empty virus (EV)-transfected cells, shown by EdU incorporation assay. Additionally, Scratch-induced wound healing assay revealed that adenovirus-mediated overexpression of WISP1 significantly increased cell migration compared with EV-transfected cells from 6h (4.56±1.14% vs. 11.23±2.25%, PMigration Assay confirmed that WISP1 overexpression significantly promoted human VSMC migration by 2.25-fold compared with EV. Furthermore, WISP1 overexpression stimulated Akt signaling activation in human VSMCs. Blockage of Akt signaling by Akt inhibitor AZD5363 or PI3K inhibitor LY294002, led to an inhibitory effect of WISP1-induced proliferation and migration in human VSMCs. Moreover, we found that WISP1 overexpression stimulated GSK3α/β phosphorylation, and increased expression of cyclin D1 and MMP9 in human VSMCs, and this effect was abolished by AZD5363. Collectively, we demonstrated that Akt signaling pathway mediates WISP1-induced migration and proliferation of human VSMCs, suggesting that WISP1 may act as a novel potential therapeutic target for vascular restenosis.

  11. A New Endogenous Overexpression System of Multidrug Transporters of Candida albicans Suitable for Structural and Functional Studies

    Directory of Open Access Journals (Sweden)

    Atanu eBanerjee

    2016-03-01

    Full Text Available Fungal pathogens have a robust array of multidrug transporters which aid in active expulsion of drugs and xenobiotics to help them evade toxic effects of drugs. Thus, these transporters impose a major impediment to effective chemotherapy. Although the Saccharomyces cerevisiae strain AD1-8u- has catered well to the need of an over-expression system to study drug transport by multidrug transporters of Candida albicans, artefacts associated with a heterologous system could not be excluded. To avoid the issue, we exploited a azole-resistant clinical isolate of C. albicans to develop a new system devoid of three major multidrug transporters (Cdr1p, Cdr2p and Mdr1p for the over-expression of multidrug transporters under native hyperactive CDR1 promoter due to gain of function (GOF mutation in TAC1. The study deals with overexpression and functional characterization of representatives of two major classes of multidrug transporters, Cdr1p and Mdr1p, to prove the functionality of this newly developed endogenous expression system. Expression of native Cdr1 and Mdr1 protein in C. albicans cells was confirmed by confocal microscopy and immunodetection and resulted in increased resistance to the putative substrates as compared to control. The system was further validated by overexpressing a few key mutant variants of Cdr1p and Mdr1p. Together, our data confirms the utility of new endogenous overexpression system which is devoid of artifactual factors as most suited for functional characterization of multidrug transporter proteins of C. albicans.

  12. Overexpression of PDGFRA cooperates with loss of NF1 and p53 to accelerate the molecular pathogenesis of malignant peripheral nerve sheath tumors.

    Science.gov (United States)

    Ki, D H; He, S; Rodig, S; Look, A T

    2017-02-23

    Malignant peripheral nerve sheath tumors (MPNSTs) are aggressive, frequently metastatic sarcomas that are associated with neurofibromatosis type 1 (NF1), a prominent inherited genetic disease in humans. Although loss of the NF1 gene predisposes to MPNST induction, relatively long tumor latency in NF1 patients suggests that additional genetic or epigenetic abnormalities are needed for the development of these nerve sheath malignancies. To study the molecular pathways contributing to the formation of MPNSTs in NF1 patients, we used a zebrafish tumor model defined by nf1 loss in a p53-deficient background together with the overexpression of either wild-type or constitutively activated PDGFRA (platelet-derived growth factor receptor-α) under control of the sox10 neural crest-specific promoter. Here we demonstrate the accelerated onset and increased penetrance of MPNST formation in fish overexpressing both the wild-type and the mutant PDGFRA transgenes in cells of neural crest origin. Interestingly, overexpression of the wild-type PDGFRA was even more potent in promoting transformation than the mutant PDGFRA, which is important because ~78% of human MPNSTs have expression of wild-type PDGFRA, whereas only 5% harbor activating mutations of the gene encoding this receptor. Further analysis revealed the induction of cellular senescence in zebrafish embryos overexpressing mutant, but not wild-type, PDGFRA, suggesting a mechanism through which the oncogenic activity of the mutant receptor is tempered by the activation of premature cellular senescence in an NF1-deficient background. Taken together, our study suggests a model in which overexpression of wild-type PDGFRA associated with NF1 deficiency leads to aberrant activation of downstream RAS signaling and thus contributes importantly to MPNST development-a prediction supported by the ability of the kinase inhibitor sunitinib alone and in combination with the MEK inhibitor trametinib to retard MPNST progression in

  13. Overexpression of PDGFRA cooperates with loss of NF1 and p53 to accelerate the molecular pathogenesis of malignant peripheral nerve sheath tumors

    Science.gov (United States)

    Ki, D H; He, S; Rodig, S; Look, A T

    2017-01-01

    Malignant peripheral nerve sheath tumors (MPNSTs) are aggressive, frequently metastatic sarcomas that are associated with neurofibromatosis type 1 (NF1), a prominent inherited genetic disease in humans. Although loss of the NF1 gene predisposes to MPNST induction, relatively long tumor latency in NF1 patients suggests that additional genetic or epigenetic abnormalities are needed for the development of these nerve sheath malignancies. To study the molecular pathways contributing to the formation of MPNSTs in NF1 patients, we used a zebrafish tumor model defined by nf1 loss in a p53-deficient background together with the overexpression of either wild-type or constitutively activated PDGFRA (platelet-derived growth factor receptor-α) under control of the sox10 neural crest-specific promoter. Here we demonstrate the accelerated onset and increased penetrance of MPNST formation in fish overexpressing both the wild-type and the mutant PDGFRA transgenes in cells of neural crest origin. Interestingly, overexpression of the wild-type PDGFRA was even more potent in promoting transformation than the mutant PDGFRA, which is important because ~78% of human MPNSTs have expression of wild-type PDGFRA, whereas only 5% harbor activating mutations of the gene encoding this receptor. Further analysis revealed the induction of cellular senescence in zebrafish embryos overexpressing mutant, but not wild-type, PDGFRA, suggesting a mechanism through which the oncogenic activity of the mutant receptor is tempered by the activation of premature cellular senescence in an NF1-deficient background. Taken together, our study suggests a model in which overexpression of wild-type PDGFRA associated with NF1 deficiency leads to aberrant activation of downstream RAS signaling and thus contributes importantly to MPNST development—a prediction supported by the ability of the kinase inhibitor sunitinib alone and in combination with the MEK inhibitor trametinib to retard MPNST progression in

  14. Silencing KRAS overexpression in arsenic-transformed prostate epithelial and stem cells partially mitigates malignant phenotype.

    Science.gov (United States)

    Ngalame, Ntube N O; Tokar, Erik J; Person, Rachel J; Waalkes, Michael P

    2014-12-01

    Inorganic arsenic is a human carcinogen that likely targets the prostate. Chronic arsenic exposure malignantly transforms the RWPE-1 human prostate epithelial line to chronic arsenic exposed-prostate epithelial (CAsE-PE) cells, and a derivative normal prostate stem cell (SC) line, WPE-stem to arsenic-cancer SCs (As-CSCs). The KRAS oncogene is highly overexpressed in CAsE-PE cells and activation precedes transformation, inferring mechanistic significance. As-CSCs also highly overexpress KRAS. Thus, we hypothesize KRAS activation is key in causing and maintaining an arsenic-induced malignant phenotype, and hence, KRAS knockdown (KD) may reverse this malignant phenotype. RNA interference using shRNAmirs to obtain KRAS KD was used in CAsE-PE and As-CSC cells. Cells analyzed 2 weeks post transduction showed KRAS protein decreased to 5% of control after KD, confirming stable KD. KRAS KD decreased phosphorylated ERK, indicating inhibition of RAS/ERK signaling, a proliferation/survival pathway activated with arsenic transformation. Secreted metalloproteinase (MMP) activity was increased by arsenic-induced malignant transformation, but KRAS KD from 4 weeks on decreased secreted MMP-9 activity by 50% in As-CSCs. Colony formation, a characteristic of cancer cells, was decreased in both KRAS KD transformants. KRAS KD also decreased the invasive capacity of both cell types. KRAS KD decreased proliferation in As-CSCs, consistent with loss of rapid tumor growth. Genes predicted to impact cell proliferation (eg, Cyclin D1, p16, and p21) changed accordingly in both KD cell types. Thus, KRAS silencing impacts aspects of arsenic-induced malignant phenotype, inducing loss of many typical cancer characteristics particularly in As-CSCs.

  15. Overexpression of circadian clock protein cryptochrome (CRY) 1 alleviates sleep deprivation-induced vascular inflammation in a mouse model.

    Science.gov (United States)

    Qin, Bing; Deng, Yunlong

    2015-01-01

    Disturbance of the circadian clock by sleep deprivation has been proposed to be involved in the regulation of inflammation. However, the underlying mechanism of circadian oscillator components in regulating the pro-inflammatory process during sleep deprivation remains poorly understood. Using a sleep deprivation mouse model, we showed here that sleep deprivation increased the expression of pro-inflammatory cytokines expression and decreased the expression of cryptochrome 1 (CRY1) in vascular endothelial cells. Furthermore, the adhesion molecules including intercellular adhesion molecule-1, vascular cell adhesion molecule-1 and E-selectin were elevated in vascular endothelial cells and the monocytes binding to vascular endothelial cells were also increased by sleep deprivation. Interestingly, overexpression of CRY1 in a mouse model by adenovirus vector significantly inhibited the expression of inflammatory cytokines and adhesion molecules, and NF-κB signal pathway activation, as well as the binding of monocytes to vascular endothelial cells. Using a luciferase reporter assay, we found that CRY1 could repress the transcriptional activity of nuclear factor (NF)-κB in vitro. Subsequently, we demonstrated that overexpression of CRY1 inhibited the basal concentration of cyclic adenosine monophosphate (cAMP), leading to decreased protein kinase A activity, which resulted in decreased phosphorylation of p65. Taken together, these results suggested that the overexpression of CRY1 inhibited sleep deprivation-induced vascular inflammation that might be associated with NF-κB and cAMP/PKA pathways.

  16. DNMT3b overexpression contributes to a hypermethylator phenotype in human breast cancer cell lines

    Directory of Open Access Journals (Sweden)

    Rivenbark Ashley G

    2008-01-01

    Full Text Available Abstract Background DNA hypermethylation events and other epimutations occur in many neoplasms, producing gene expression changes that contribute to neoplastic transformation, tumorigenesis, and tumor behavior. Some human cancers exhibit a hypermethylator phenotype, characterized by concurrent DNA methylation-dependent silencing of multiple genes. To determine if a hypermethylation defect occurs in breast cancer, the expression profile and promoter methylation status of methylation-sensitive genes were evaluated among breast cancer cell lines. Results The relationship between gene expression (assessed by RT-PCR and quantitative real-time PCR, promoter methylation (assessed by methylation-specific PCR, bisulfite sequencing, and 5-aza-2'deoxycytidine treatment, and the DNA methyltransferase machinery (total DNMT activity and expression of DNMT1, DNMT3a, and DNMT3b proteins were examined in 12 breast cancer cell lines. Unsupervised cluster analysis of the expression of 64 methylation-sensitive genes revealed two groups of cell lines that possess distinct methylation signatures: (i hypermethylator cell lines, and (ii low-frequency methylator cell lines. The hypermethylator cell lines are characterized by high rates of concurrent methylation of six genes (CDH1, CEACAM6, CST6, ESR1, LCN2, SCNN1A, whereas the low-frequency methylator cell lines do not methylate these genes. Hypermethylator cell lines coordinately overexpress total DNMT activity and DNMT3b protein levels compared to normal breast epithelial cells. In contrast, most low-frequency methylator cell lines possess DNMT activity and protein levels that are indistinguishable from normal. Microarray data mining identified a strong cluster of primary breast tumors that express the hypermethylation signature defined by CDH1, CEACAM6, CST6, ESR1, LCN2, and SCNN1A. This subset of breast cancers represents 18/88 (20% tumors in the dataset analyzed, and 100% of these tumors were classified as basal

  17. Overexpression of X-linked genes in T cells from women with lupus.

    Science.gov (United States)

    Hewagama, Anura; Gorelik, Gabriela; Patel, Dipak; Liyanarachchi, Punsisi; McCune, W Joseph; Somers, Emily; Gonzalez-Rivera, Tania; Strickland, Faith; Richardson, Bruce

    2013-03-01

    Women develop lupus more frequently than men and the reason remains incompletely understood. Evidence that men with Klinefelter's Syndrome (XXY) develop lupus at approximately the same rate as women suggests that a second X chromosome contributes. However, since the second X is normally inactivated, how it predisposes to lupus is unclear. DNA methylation contributes to the silencing of one X chromosome in women, and CD4+ T cell DNA demethylation contributes to the development of lupus-like autoimmunity. This suggests that demethylation of genes on the inactive X may predispose women to lupus, and this hypothesis is supported by a report that CD40LG, an immune gene encoded on the X chromosome, demethylates and is overexpressed in T cells from women but not men with lupus. Overexpression of other immune genes on the inactive X may also predispose women to this disease. We therefore compared mRNA and miRNA expression profiles in experimentally demethylated T cells from women and men as well as in T cells from women and men with lupus. T cells from healthy men and women were treated with the DNA methyltransferase inhibitor 5-azacytidine, then X-linked mRNAs were surveyed with oligonucleotide arrays, and X-linked miRNA's surveyed with PCR arrays. CD40LG, CXCR3, OGT, miR-98, let-7f-2*, miR 188-3p, miR-421 and miR-503 were among the genes overexpressed in women relative to men. MiRNA target prediction analyses identified CBL, which downregulates T cell receptor signaling and is decreased in lupus T cells, as a gene targeted by miR-188-3p and miR-98. Transfection with miR-98 and miR-188-3p suppressed CBL expression. The same mRNA and miRNA transcripts were also demethylated and overexpressed in CD4+ T cells from women relative to men with active lupus. Together these results further support a role for X chromosome demethylation in the female predisposition to lupus.

  18. Adenoviral overexpression of Lhx2 attenuates cell viability but does not preserve the stem cell like phenotype of hepatic stellate cells

    Energy Technology Data Exchange (ETDEWEB)

    Genz, Berit [Institute for Experimental Surgery, Rostock University Medical Center, Rostock (Germany); Thomas, Maria [Dr. Margarete Fischer-Bosch Institute of Clinical Pharmacology, Stuttgart (Germany); Pützer, Brigitte M. [Institute of Experimental Gene Therapy and Cancer Research, Rostock University Medical Center, Rostock (Germany); Siatkowski, Marcin; Fuellen, Georg [Institute for Biostatistics and Informatics in Medicine and Ageing Research, Rostock University Medical Center, Rostock (Germany); Vollmar, Brigitte [Institute for Experimental Surgery, Rostock University Medical Center, Rostock (Germany); Abshagen, Kerstin, E-mail: kerstin.abshagen@uni-rostock.de [Institute for Experimental Surgery, Rostock University Medical Center, Rostock (Germany)

    2014-11-01

    Hepatic stellate cells (HSC) are well known initiators of hepatic fibrosis. After liver cell damage, HSC transdifferentiate into proliferative myofibroblasts, representing the major source of extracellular matrix in the fibrotic organ. Recent studies also demonstrate a role of HSC as progenitor or stem cell like cells in liver regeneration. Lhx2 is described as stem cell maintaining factor in different organs and as an inhibitory transcription factor in HSC activation. Here we examined whether a continuous expression of Lhx2 in HSC could attenuate their activation and whether Lhx2 could serve as a potential target for antifibrotic gene therapy. Therefore, we evaluated an adenoviral mediated overexpression of Lhx2 in primary HSC and investigated mRNA expression patterns by qRT-PCR as well as the activation status by different in vitro assays. HSC revealed a marked increase in activation markers like smooth muscle actin alpha (αSMA) and collagen 1α independent from adenoviral transduction. Lhx2 overexpression resulted in attenuated cell viability as shown by a slightly hampered migratory and contractile phenotype of HSC. Expression of stem cell factors or signaling components was also unaffected by Lhx2. Summarizing these results, we found no antifibrotic or stem cell maintaining effect of Lhx2 overexpression in primary HSC. - Highlights: • We performed adenoviral overexpression of Lhx2 in primary hepatic stellate cells. • Hepatic stellate cells expressed stem cell markers during cultivation. • Cell migration and contractility was slightly hampered upon Lhx2 overexpression. • Lhx2 overexpression did not affect stem cell character of hepatic stellate cells.

  19. Overexpression of NOTCH-regulated Ankyrin Repeat Protein is associated with papillary thyroid carcinoma progression

    Science.gov (United States)

    Zhang, Mingdi; Qin, Yiyu; Zuo, Bin; Gong, Wei; Zhang, Shenglai; Gong, Yurong; Quan, Zhiwei; Chu, Bingfeng

    2017-01-01

    Papillary thyroid cancer (PTC) is one of the endocrine cancers with high clinical and genetic heterogeneity. NOTCH signaling and its downstream NOTCH-Regulated Ankyrin Repeat Protein (NRARP) have been implicated in oncogenesis of many cancers, but the roles in PTCs are less studied. In this study, we show that NRARP is frequently over-expressed in thyroid carcinoma. The over-activation of NRARP is highly and positively correlated with NOTCH genes. Moreover, we find that the expression of NRARP is highly associated with several epithelial mesenchymal transition (EMT) markers and contributes to poor survival outcomes. Therefore, these results indicate that NRARP is an important clinical biomarker in thyroid carcinoma and it promotes EMT induction as well as the progression of PTCs via NOTCH signaling activation. PMID:28207739

  20. Regulation of Alternative Splicing in Vivo by Overexpression of Antagonistic Splicing Factors

    Science.gov (United States)

    Caceres, Javier F.; Stamm, Stefan; Helfman, David M.; Krainer, Adrian R.

    1994-09-01

    The opposing effects of SF2/ASF and heterogeneous nuclear ribonucleoprotein (hnRNP) A1 influence alternative splicing in vitro. SF2/ASF or hnRNP A1 complementary DNAs were transiently overexpressed in HeLa cells, and the effect on alternative splicing of several cotransfected reporter genes was measured. Increased expression of SF2/ASF activated proximal 5' splice sites, promoted inclusion of a neuron-specific exon, and prevented abnormal exon skipping. Increased expression of hnRNP A1 activated distal 5' splice sites. Therefore, variations in the intracellular levels of antagonistic splicing factors influence different modes of alternative splicing in vivo and may be a natural mechanism for tissue-specific or developmental regulation of gene expression.

  1. Overexpression of Dishevelled-2 contributes to proliferation and migration of human esophageal squamous cell carcinoma.

    Science.gov (United States)

    Zhou, Guoren; Ye, Jinjun; Sun, Lei; Zhang, Zhi; Feng, Jifeng

    2016-06-01

    Dishevelled-2 (Dvl2) was associated with tumor cell proliferation and migration. We aimed to examine the mechanism of Dvl2 in esophageal squamous cell carcinoma (ESCC). Dvl2 was overexpressed in human ESCC tissues and cell lines ECA109 and TE1 cells. CCK-8 and colony formation assay was performed to evaluate the proliferation in ECA109 cells transfected with Dvl2-shRNA. Wound-healing assay and transwell assay were used to examine the activities of migration and invasion in Dvl2-silenced ESCC cells. Knockdown of Dvl2 significantly reduced ECA109 cell proliferation and migration. Moreover, we demonstrated that the proliferation and migration ability of Dvl2 might through the activation of Wnt pathway by targeting the Cyclin D1 and MMP-9. We came to the conclusion that the proliferation and migration effects of Dvl2 might contribute to malignant development of human ESCC.

  2. Overexpression of a Chitinase Gene from Trichoderma asperellum Increases Disease Resistance in Transgenic Soybean.

    Science.gov (United States)

    Zhang, Fuli; Ruan, Xianle; Wang, Xian; Liu, Zhihua; Hu, Lizong; Li, Chengwei

    2016-12-01

    In the present study, a chi gene from Trichoderma asperellum, designated Tachi, was cloned and functionally characterized in soybean. Firstly, the effects of sodium thiosulfate on soybean Agrobacterium-mediated genetic transformation with embryonic tip regeneration system were investigated. The transformation frequency was improved by adding sodium thiosulfate in co-culture medium for three soybean genotypes. Transgenic soybean plants with constitutive expression of Tachi showed increased resistance to Sclerotinia sclerotiorum compared to WT plants. Meanwhile, overexpression of Tachi in soybean exhibited increased reactive oxygen species (ROS) level as well as peroxidase (POD) and catalase (SOD) activities, decreased malondialdehyde (MDA) content, along with diminished electrolytic leakage rate after S. sclerotiorum inoculation. These results suggest that Tachi can improve disease resistance in plants by enhancing ROS accumulation and activities of ROS scavenging enzymes and then diminishing cell death. Therefore, Tachi represents a candidate gene with potential application for increasing disease resistance in plants.

  3. SET overexpression decreases cell detoxification efficiency: ALDH2 and GSTP1 are downregulated, DDR is impaired and DNA damage accumulates.

    Science.gov (United States)

    Almeida, Luciana O; Goto, Renata N; Pestana, Cezar R; Uyemura, Sérgio A; Gutkind, Silvio; Curti, Carlos; Leopoldino, Andréia M

    2012-12-01

    Alcohol and tobacco consumption are risk factors for head and neck squamous cell carcinoma (HNSCC). Aldehyde dehydrogenase 2 (ALDH2) and glutathione S-transferase pi 1 (GSTP1) are important enzymes for cellular detoxification and low efficiencies are implicated in cancer. We assessed the potential role of SET protein overexpression, a histone acetylation modulator accumulated in HNSCC, in gene regulation and protein activity of ALDH2 and GSTP1. SET was knocked down in HN13, HN12 and Cal27, and overexpressed in HEK293 cells; ethanol and cisplatin were the chemical agents. Cells with SET overexpression (HEK293/SET, HN13 and HN12) showed lower ALDH2 and GSTP1 mRNA levels and trichostatin A increased them (real-time PCR). Ethanol upregulated GSTP1 and ALDH2 mRNAs, whereas cisplatin upregulated GSTP1 in HEK293 cells. SET-chromatin binding revealed SET interaction with ALDH2 and GSTP1 promoters, specifically via SET NAP domain; ethanol and cisplatin abolished SET binding. ALDH2 and GSTP1 efficiency was assessed by enzymatic and comet assay. A lower ALDH2 activity was associated with greater DNA damage (tail intensity) in HEK293/SET compared with HEK293 cells, whereas HN13/siSET showed ALDH2 activity higher than HN13 cells. HN13/siSET cells showed increased tail intensity. Cisplatin-induced DNA damage response showed negative relationship between SET overexpression and BRCA2 recruitment. SET downregulated repair genes ATM, BRCA1 and CHEK2 and upregulated TP53. Cisplatin-induced cell-cycle arrest occurred in G(0) /G(1) and S in HEK293 cells, whereas HEK293/SET showed G(2) /M stalling. Overall, cisplatin was more cytotoxic for HN13 than HN13/siSET cells. Our data suggest a role for SET in cellular detoxification, DNA damage response and genome integrity.

  4. A novel amino acid and metabolomics signature in mice overexpressing muscle uncoupling protein 3.

    Science.gov (United States)

    Aguer, Céline; Piccolo, Brian D; Fiehn, Oliver; Adams, Sean H; Harper, Mary-Ellen

    2017-02-01

    Uncoupling protein 3 (UCP3) is highly selectively expressed in skeletal muscle and is known to lower mitochondrial reactive oxygen species and promote fatty acid oxidation; however, the global impact of UCP3 activity on skeletal muscle and whole-body metabolism have not been extensively studied. We utilized untargeted metabolomics to identify novel metabolites that distinguish mice overexpressing UCP3 in muscle, both at rest and after exercise regimens that challenged muscle metabolism, to potentially unmask subtle phenotypes. Male wild-type (WT) and muscle-specific UCP3-overexpressing transgenic (UCP3 Tg) C57BL/6J mice were compared with or without a 5 wk endurance training protocol at rest or after an acute exercise bout (EB). Skeletal muscle, liver, and plasma samples were analyzed by gas chromatography time-of-flight mass spectrometry. Discriminant metabolites were considered if within the top 99th percentile of variable importance measurements obtained from partial least-squares discriminant analysis models. A total of 80 metabolites accurately discriminated UCP3 Tg mice from WT when modeled within a specific exercise condition (i.e., untrained/rested, endurance trained/rested, untrained/EB, and endurance trained/EB). Results revealed that several amino acids and amino acid derivatives in skeletal muscle and plasma of UCP3 Tg mice (e.g., Asp, Glu, Lys, Tyr, Ser, Met) were significantly reduced after an EB; that metabolites associated with skeletal muscle glutathione/Met/Cys metabolism (2-hydroxybutanoic acid, oxoproline, Gly, and Glu) were altered in UCP3 Tg mice across all training and exercise conditions; and that muscle metabolite indices of dehydrogenase activity were increased in UCP3 Tg mice, suggestive of a shift in tissue NADH/NAD(+) ratio. The results indicate that mitochondrial UCP3 activity affects metabolism well beyond fatty acid oxidation, regulating biochemical pathways associated with amino acid metabolism and redox status. That select

  5. Differences in radiosensitivity between three HER2 overexpressing cell lines

    Energy Technology Data Exchange (ETDEWEB)

    Steffen, Ann-Charlott; Tolmachev, Vladimir; Stenerloew, Bo [Uppsala University, Unit of Biomedical Radiation Sciences, Department of Oncology, Radiology and Clinical Immunology, Rudbeck Laboratory, Uppsala (Sweden); Goestring, Lovisa [Affibody AB, Bromma (Sweden); Palm, Stig [Sahlgrenska Academy at Goeteborg University, Department of Radiation Physics, Goeteborg (Sweden); Carlsson, Joergen [Uppsala University, Unit of Biomedical Radiation Sciences, Department of Oncology, Radiology and Clinical Immunology, Rudbeck Laboratory, Uppsala (Sweden); Rudbeck Laboratory, Biomedical Radiation Sciences, Uppsala (Sweden)

    2008-06-15

    HER2 is a potential target for radionuclide therapy, especially when HER2 overexpressing breast cancer cells are resistant to Herceptin {sup registered} treatment. Therefore, it is of interest to analyse whether HER2 overexpressing tumour cells have different inherent radiosensitivity. The radiosensitivity of three often used HER2 overexpressing cell lines, SKOV-3, SKBR-3 and BT-474, was analysed. The cells were exposed to conventional photon irradiation, low linear energy transfer (LET), to characterise their inherent radiosensitivity. The analysis was made with clonogenic survival and growth extrapolation assays. The cells were also exposed to alpha particles, high LET, from {sup 211}At decays using the HER2-binding affibody molecule {sup 211}At-(Z{sub HER2:4}){sub 2} as targeting agent. Assays for studies of internalisation of the affibody molecule were applied. SKOV-3 cells were most radioresistant, SKBR-3 cells were intermediate and BT-474 cells were most sensitive as measured with the clonogenic and growth extrapolation assays after photon irradiation. The HER2 dependent cellular uptake of {sup 211}At was qualitatively similar for all three cell lines. However, the sensitivity to the alpha particles from {sup 211}At differed; SKOV-3 was most resistant, SKBR-3 intermediate and BT-474 most sensitive. These differences were unexpected because it is assumed that all types of cells should have similar sensitivity to high-LET radiation. The sensitivity to alpha particle exposure correlated with internalisation of the affibody molecule and with size of the cell nucleus. There can be differences in radiosensitivity, which, if they also exist between patient breast cancer cells, are important to consider for both conventional radiotherapy and for HER2-targeted radionuclide therapy. (orig.)

  6. Effects of ADH2 overexpression in Saccharomyces bayanus during alcoholic fermentation.

    Science.gov (United States)

    Maestre, Oscar; García-Martínez, Teresa; Peinado, Rafael A; Mauricio, Juan C

    2008-02-01

    The effect of overexpression of the gene ADH2 on metabolic and biological activity in Saccharomyces bayanus V5 during alcoholic fermentation has been evaluated. This gene is known to encode alcohol dehydrogenase II (ADH II). During the biological aging of sherry wines, where yeasts have to grow on ethanol owing to the absence of glucose, this isoenzyme plays a prominent role by converting the ethanol into acetaldehyde and producing NADH in the process. Overexpression of the gene ADH2 during alcoholic fermentation has no effect on the proteomic profile or the net production of some metabolites associated with glycolysis and alcoholic fermentation such as ethanol, acetaldehyde, and glycerol. However, it affects indirectly glucose and ammonium uptakes, cell growth, and intracellular redox potential, which lead to an altered metabolome. The increased contents in acetoin, acetic acid, and L-proline present in the fermentation medium under these conditions can be ascribed to detoxification by removal of excess acetaldehyde and the need to restore and maintain the intracellular redox potential balance.

  7. Overexpression of Nelumbo nucifera metallothioneins 2a and 3 enhances seed germination vigor in Arabidopsis.

    Science.gov (United States)

    Zhou, Yuliang; Chu, Pu; Chen, Huhui; Li, Yin; Liu, Jun; Ding, Yu; Tsang, Edward W T; Jiang, Liwen; Wu, Keqiang; Huang, Shangzhi

    2012-03-01

    Metallothioneins (MTs) are small, cysteine-rich and metal-binding proteins which are involved in metal homeostasis and scavenging of reactive oxygen species. Although plant MTs have been intensively studied, their roles in seeds remain to be clearly established. Here, we report the isolation and characterization of NnMT2a, NnMT2b and NnMT3 from sacred lotus (Nelumbo nucifera Gaertn.) and their roles in seed germination vigor. The transcripts of NnMT2a, NnMT2b and NnMT3 were highly expressed in developing and germinating sacred lotus seeds, and were dramatically up-regulated in response to high salinity, oxidative stresses and heavy metals. Analysis of transformed Arabidopsis protoplasts showed that NnMT2a-YFP and NnMT3-YFP were localized in cytoplasm and nucleoplasm. Transgenic Arabidopsis seeds overexpressing NnMT2a and NnMT3 displayed improved resistance to accelerated aging (AA) treatment, indicating their significant roles in seed germination vigor. These transgenic seeds also exhibited higher superoxide dismutase activity compared to wild-type seeds after AA treatment. In addition, we showed that NnMT2a and NnMT3 conferred improved germination ability to NaCl and methyl viologen on transgenic Arabidopsis seeds. Taken together, these data demonstrate that overexpression of NnMT2a and NnMT3 in Arabidopsis significantly enhances seed germination vigor after AA treatment and under abiotic stresses.

  8. Overexpression of phytochelatin synthase in Arabidopsis leads to enhanced arsenic tolerance and cadmium hypersensitivity.

    Science.gov (United States)

    Li, Yujing; Dhankher, Om Parkash; Carreira, Laura; Lee, David; Chen, Alice; Schroeder, Julian I; Balish, Rebecca S; Meagher, Richard B

    2004-12-01

    Phytochelatin synthase (PCS) catalyzes the final step in the biosynthesis of phytochelatins, which are a family of cysteine-rich thiol-reactive peptides believed to play important roles in processing many thiol-reactive toxicants. A modified Arabidopsis thaliana PCS sequence (AtPCS1) was active in Escherichia coli. When AtPCS1 was overexpressed in Arabidopsis from a strong constitutive Arabidopsis actin regulatory sequence (A2), the A2::AtPCS1 plants were highly resistant to arsenic, accumulating 20-100 times more biomass on 250 and 300 microM arsenate than wild type (WT); however, they were hypersensitive to Cd(II). After exposure to cadmium and arsenic, the overall accumulation of thiol-peptides increased to 10-fold higher levels in the A2::AtPCS1 plants compared with WT, as determined by fluorescent HPLC. Whereas cadmium induced greater increases in traditional PCs (PC2, PC3, PC4), arsenic exposure resulted in the expression of many unknown thiol products. Unexpectedly, after arsenate or cadmium exposure, levels of the dipeptide substrate for PC synthesis, gamma-glutamyl cysteine (gamma-EC), were also dramatically increased. Despite these high thiol-peptide concentrations, there were no significant increases in concentrations of arsenic and cadmium in above-ground tissues in the AtPCS1 plants relative to WT plants. The potential for AtPCS1 overexpression to be useful in strategies for phytoremediating arsenic and to compound the negative effects of cadmium are discussed.

  9. Mannose 6-Phosphate Receptor Is Reduced in -Synuclein Overexpressing Models of Parkinsons Disease

    Science.gov (United States)

    Matrone, Carmela; Dzamko, Nicolas; Madsen, Peder; Nyegaard, Mette; Pohlmann, Regina; Søndergaard, Rikke V.; Lassen, Louise B.; Andresen, Thomas L.; Halliday, Glenda M.; Jensen, Poul Henning

    2016-01-01

    Increasing evidence points to defects in autophagy as a common denominator in most neurodegenerative conditions. Progressive functional decline in the autophagy-lysosomal pathway (ALP) occurs with age, and the consequent impairment in protein processing capacity has been associated with a higher risk of neurodegeneration. Defects in cathepsin D (CD) processing and α-synuclein degradation causing its accumulation in lysosomes are particularly relevant for the development of Parkinson's disease (PD). However, the mechanism by which alterations in CD maturation and α-synuclein degradation leads to autophagy defects in PD neurons is still uncertain. Here we demonstrate that MPR300 shuttling between endosomes and the trans Golgi network is altered in α-synuclein overexpressing neurons. Consequently, CD is not correctly trafficked to lysosomes and cannot be processed to generate its mature active form, leading to a reduced CD-mediated α-synuclein degradation and α-synuclein accumulation in neurons. MPR300 is downregulated in brain from α-synuclein overexpressing animal models and in PD patients with early diagnosis. These data indicate MPR300 as crucial player in the autophagy-lysosomal dysfunctions reported in PD and pinpoint MRP300 as a potential biomarker for PD. PMID:27509067

  10. Effects of over-expressing resistin on glucose and lipid metabolism in mice

    Institute of Scientific and Technical Information of China (English)

    You LIU; Qun WANG; Ying-bin PAN; Zhi-jie GAO; Yan-fen LIU; Shao-hong CHEN

    2008-01-01

    Resistin, a newly discovered peptide hormone mainly secreted by adipose tissues, is present at high levels in serum of obese mice and may be a potential link between obesity and insulin resistance in rodents. However, some studies of rat and mouse models have associated insulin resistance and obesity with decreased resistin expression. In humans, no relationship between resistin level and insulin resistance or adiposity was observed. This suggests that additional studies are necessary to determine the specific role of resistin in the regulation of energy metabolism and adipogenesis. In the present study, we investigated the effect of resistin in vivo on glucose and lipid metabolism by over-expressing resistin in mice by intramuscular injection of a recombinant eukaryotic expression vector pcDNA3.1-Retn encoding porcine resistin gene. After injection, serum resistin and serum glucose (GLU) levels were significantly increased in the pcDNA3.1-Retn-treated mice; there was an obvious difference in total cholesterol (TC) level between the experiment and the control groups on Day 30. In pcDNA3.1-Retn-treated mice, both free fatty acid (FFA) and high density lipoprotein (HDL) cholesterol levels were markedly lower than those of control, whereas HDL cholesterol and triglyceride (TG) levels did not differ between the two groups. Furthermore, lipase activity was expressly lower on Day 20. Our data suggest that resistin over-expressed in mice might be responsible for insulin resistance and parameters related to glucose and lipid metabolism were changed accordingly.

  11. Heme oxygenase-1 overexpression increases liver injury after bile duct ligation in rats

    Institute of Scientific and Technical Information of China (English)

    Matthias Froh; Ronald G Thurman; Lars Conzelmann; Peter Walbrun; Susanne Netter; Reiner Wiest; Michael D Wheeler; Mark Lehnert; Takehiko Uesugi; Jurgen Scholmerich

    2007-01-01

    AIM: To investigate the effects of heme oxygenase-1(HO-1) against oxidant-induced injury caused by bile duct ligation (BDL).METHODS: Either cobalt protoporphyrin (CoPP), a HO-1 inducer, or saline were injected intraperitoneally in male SD-rats. Three days later, BDL or sham-operations were performed. Rats were sacrificed 3 wk after BDL and livers were harvested for histology. Fibrosis was evaluated by sirius red staining and image analysis.Alpha-smooth muscular actin, which indicates activation of stellate cells, was detected by immunohistochemical staining, and cytokine and collagen- Ⅰα (Col- Ⅰα) mRNA expression was detected using RNase protection assays.RESULTS: Serum alanine transaminase increased 8-fold above normal levels one day after BDL. Surprisingly,enzyme release was not reduced in rats receiving CoPP.Liver fibrosis was evaluated 3 wk after BDL and the sirius red-positive area was found to be increased to about 7.8%. However, in CoPP pretreated rats sirius redpositive areas were increased to about 11.7% after BDL.Collagen- Ⅰα and TGF-β mRNA increased significantly by BDL. Again, this effect was increased by HO-1overexpression.CONCLUSION: Hepatic fibrosis due to BDL is not reduced by the HO-1 inducer CoPP. In contrast, HO-1overexpression increases liver injury in rats under conditions of experimental chronic cholestasis.

  12. Enhanced flux through the methylerythritol 4-phosphate pathway in Arabidopsis plants overexpressing deoxyxylulose 5-phosphate reductoisomerase.

    Science.gov (United States)

    Carretero-Paulet, Lorenzo; Cairó, Albert; Botella-Pavía, Patricia; Besumbes, Oscar; Campos, Narciso; Boronat, Albert; Rodríguez-Concepción, Manuel

    2006-11-01

    The methylerythritol 4-phosphate (MEP) pathway synthesizes the precursors for an astonishing diversity of plastid isoprenoids, including the major photosynthetic pigments chlorophylls and carotenoids. Since the identification of the first two enzymes of the pathway, deoxyxylulose 5-phoshate (DXP) synthase (DXS) and DXP reductoisomerase (DXR), they both were proposed as potential control points. Increased DXS activity has been shown to up-regulate the production of plastid isoprenoids in all systems tested, but the relative contribution of DXR to the supply of isoprenoid precursors is less clear. In this work, we have generated transgenic Arabidopsis thaliana plants with altered DXS and DXR enzyme levels, as estimated from their resistance to clomazone and fosmidomycin, respectively. The down-regulation of DXR resulted in variegation, reduced pigmentation and defects in chloroplast development, whereas DXR-overexpressing lines showed an increased accumulation of MEP- derived plastid isoprenoids such as chlorophylls, carotenoids, and taxadiene in transgenic plants engineered to produce this non-native isoprenoid. Changes in DXR levels in transgenic plants did not result in changes in DXS gene expression or enzyme accumulation, confirming that the observed effects on plastid isoprenoid levels in DXR-overexpressing lines were not an indirect consequence of altering DXS levels. The results indicate that the biosynthesis of MEP (the first committed intermediate of the pathway) limits the production of downstream isoprenoids in Arabidopsis chloroplasts, supporting a role for DXR in the control of the metabolic flux through the MEP pathway.

  13. Overexpression of transcriptional coactivator AIB1 promotes hepatocellular carcinoma progression by enhancing cell proliferation and invasiveness.

    Science.gov (United States)

    Xu, Y; Chen, Q; Li, W; Su, X; Chen, T; Liu, Y; Zhao, Y; Yu, C

    2010-06-10

    Amplified in breast cancer 1 (AIB1) is a transcriptional coactivator for nuclear receptors and other transcription factors. AIB1 has an important role in malignancy of several cancers such as breast and prostate cancers. However, its involvement in human hepatocellular carcinoma (HCC) progression remains unclear. Here, we found that AIB1 protein was overexpressed in 23 of 34 human HCC specimens (68%). Down-regulation of AIB1 reduced HCC cell proliferation, migration, invasion, colony formation ability and tumorigenic potential in nude mice. These phenotypic changes caused by AIB1 knockdown correlated with increased expression of the cell cycle inhibitor p21(Cip1/Waf1) and decreased Akt activation and the expression of proliferating cell nuclear antigen (PCNA) and matrix metallopeptidase MMP-9. In agreement with these findings, clinical AIB1-positive HCC expressed higher levels of PCNA than AIB1-negative HCC. A positive correlation was established between the levels of AIB1 protein and PCNA protein in HCC, suggesting that AIB1 may contribute to HCC cell proliferation. In addition, MMP-9 expression in AIB1-postive HCC was significantly higher than that in AIB1-negative HCC, suggesting that AIB1-postive HCC may be more invasive. Collectively, our results show that overexpression of AIB1 promotes human HCC progression by enhancing cell proliferation and invasiveness. Therefore, AIB1 is a master regulator of human HCC growth and might be a useful molecular target for HCC prognosis and treatment.

  14. Molecular characterization and homologous overexpression of [FeFe]-hydrogenase in Clostridium tyrobutyricum JM1

    Energy Technology Data Exchange (ETDEWEB)

    Jo, Ji Hye [Biosciences Center, National Renewable Energy Laboratory, 1617 Cole Blvd, Golden, CO 80401-3393 (United States); Jeon, Che Ok [Department of Life Science, Chung-Ang University, Seoul 156-756 (Korea); Lee, Seung Yoon [K-water Research Institute, Korea Water Resources Corporation, 462-1, Jeonmin-dong, Yuseong-gu, Daejon 305-703 (Korea); Lee, Dae Sung [Department of Environmental Engineering, Kyungpook National University, 1370 Sankyuk-dong, Buk-gu, Daegu 702-701 (Korea); Park, Jong Moon [Department of Chemical Engineering, Pohang University of Science and Technology, San 31, Hyoja-dong, Nam-gu, Pohang, Gyeongbuk 790-784 (Korea)

    2010-02-15

    The H{sub 2}-evoving [FeFe]-hydrogenase in Clostridium tyrobutyricum JM1 was isolated to elucidate molecular characterization and modular structure of the hydrogenase. Then, homologous overexpression of the hydrogenase gene was for the first time performed to enhance hydrogen production. The hydA open reading frame (ORF) was 1734-bp, encodes 577 amino acids with a predicted molecular mass of 63,970 Da, and presents 80% and 75% identity at the amino acid level with the [FeFe]-hydrogenase genes of Clostridium kluyveri DSM 555 and Clostridium acetobutylicum ATCC 824, respectively. One histidine residue and 19 cysteine residues, known to fasten one [2Fe-2S] cluster, three [4Fe-4S] clusters and one H-cluster, were conserved in hydA of C. tyrobutyricum. A 2327-bp DNA region containing the ORF and the putative promoter region was amplified and subcloned into a pJIR418 shuttle vector. The gene transfer of the recombinant plasmid into C. tyrobutyricum JM1 was performed by a modified electrotransformation method. Homologous overexpression of the [FeFe]-hydrogenase gene resulted in a 1.7-fold and 1.5-fold increase in hydrogenase activity and hydrogen yield concomitant with the shift of metabolic pathway. (author)

  15. Overexpression of a proton-coupled vacuolar glucose exporter impairs freezing tolerance and seed germination.

    Science.gov (United States)

    Klemens, Patrick A W; Patzke, Kathrin; Trentmann, Oliver; Poschet, Gernot; Büttner, Michael; Schulz, Alexander; Marten, Irene; Hedrich, Rainer; Neuhaus, H Ekkehard

    2014-04-01

    Arabidopsis vacuoles harbor, besides sugar transporter of the TMT-type, an early response to dehydration like 6 (ERDL6) protein involved in glucose export into the cytosol. However, the mode of transport of ERDL6 and the plant's feedback to overexpression of its activity on essential properties such as, for example, seed germination or freezing tolerance, remain unexplored. Using patch-clamp studies on vacuoles expressing AtERDL6 we demonstrated directly that this carrier operates as a proton-driven glucose exporter. Overexpression of BvIMP, the closest sugar beet (Beta vulgaris) homolog to AtERDL6, in Arabidopsis leads surprisingly to impaired seed germination under both conditions, sugar application and low environmental temperatures, but not under standard conditions. Upon cold treatment, BvIMP overexpressor plants accumulated lower quantities of monosaccharides than the wild-type, a response in line with the reduced frost tolerance of the transgenic Arabidopsis plants, and the fact that cold temperatures inhibits BvIMP transcription in sugar beet leaves. With these findings we show that the tight control of vacuolar sugar import and export is a key requisite for cold tolerance and seed germination of plants.

  16. Selenium status and over-expression of interleukin-15 in celiac disease and autoimmune thyroid diseases

    Directory of Open Access Journals (Sweden)

    Anna Velia Stazi

    2010-12-01

    Full Text Available In celiac disease (CD, for its multifactorial nature, the target organs are not limited to the gut, but include thyroid, liver, skin and reproductive and nervous systems. Between the extraintestinal symptoms associated with CD, autoimmune thyroid diseases (AITDs are more evident, underlining as CD-related autoimmune alterations can be modulated not only by gluten but also by various concurrent endogenous (genetic affinity, over-expression of cytokines and exogenous (environment, nutritional deficiency factors. In their pathogenesis a central role for over-expression of interleukin-15 (IL-15 is shown, by inhibiting apoptosis, leading to the perpetuation of inflammation and tissue destruction. Thyroid is particularly sensitive to selenium deficiency because selenoproteins are significant in biosynthesis and activity of thyroid hormones; besides, some selenoproteins as glutathione peroxidase are involved in inhibiting apoptosis. Thus, selenium malabsorption in CD can be thought as a key factor directly leading to thyroid and intestinal damage. Considering the complexity of this interaction and on the basis of available evidence, the aim of this review is to assess as preventive and therapeutic target the role of IL-15 and selenium in the pathogeneses of both CD and AITD.

  17. Effect of MexXY overexpression on ceftobiprole susceptibility in Pseudomonas aeruginosa.

    Science.gov (United States)

    Baum, Ellen Z; Crespo-Carbone, Steven M; Morrow, Brian J; Davies, Todd A; Foleno, Barbara D; He, Wenping; Queenan, Anne Marie; Bush, Karen

    2009-07-01

    Ceftobiprole, an anti-methicillin-resistant Staphylococcus aureus broad-spectrum cephalosporin, has activity (MIC for 50% of strains tested, ceftobiprole clinical studies, paired isolates of P. aeruginosa from four subjects demonstrated ceftobiprole MICs of 2 to 4 microg/ml at baseline but 16 microg/ml posttreatment, unrelated to beta-lactamase levels. Within each pair, the level of mexXY RNA, but not mexAB, mexCD, and mexEF, increased by an average of 50-fold from baseline to posttreatment isolates. Sequencing of the negative regulatory gene mexZ indicated that each posttreatment isolate contained a mutation not present at baseline. mexXY expression as a primary ceftobiprole and cefepime resistance mechanism was further examined in isogenic pairs by using cloned mexXY and mexZ. Expression of cloned mexXY in strain PAO1 or in a baseline isolate increased the ceftobiprole MIC to that for the posttreatment isolate. In contrast, in posttreatment isolates, lowering mexXY expression via introduction of cloned mexZ decreased the ceftobiprole MIC to that for the baseline isolates. Similar changes were observed for cefepime. A spontaneous mutant selectively overexpressing mexXY displayed a fourfold elevation in its ceftobiprole MIC, while overexpression of mexAB, -CD, and -EF had a minimal effect. These data indicate that ceftobiprole, like cefepime, is an atypical beta-lactam that is a substrate for the MexXY efflux pump in P. aeruginosa.

  18. Bacterial glyphosate resistance conferred by overexpression of an E. coli membrane efflux transporter.

    Science.gov (United States)

    Staub, Jeffrey M; Brand, Leslie; Tran, Minhtien; Kong, Yifei; Rogers, Stephen G

    2012-04-01

    Glyphosate herbicide-resistant crop plants, introduced commercially in 1994, now represent approximately 85% of the land area devoted to transgenic crops. Herbicide resistance in commercial glyphosate-resistant crops is due to expression of a variant form of a bacterial 5-enolpyruvylshikimate-3-phosphate synthase with a significantly decreased binding affinity for glyphosate at the target site of the enzyme. As a result of widespread and recurrent glyphosate use, often as the only herbicide used for weed management, increasing numbers of weedy species have evolved resistance to glyphosate. Weed resistance is most often due to changes in herbicide translocation patterns, presumed to be through the activity of an as yet unidentified membrane transporter in plants. To provide insight into glyphosate resistance mechanisms and identify a potential glyphosate transporter, we screened Escherichia coli genomic DNA for alternate sources of glyphosate resistance genes. Our search identified a single non-target gene that, when overexpressed in E. coli and Pseudomonas, confers high-level glyphosate resistance. The gene, yhhS, encodes a predicted membrane transporter of the major facilitator superfamily involved in drug efflux. We report here that an alternative mode of glyphosate resistance in E. coli is due to reduced accumulation of glyphosate in cells that overexpress this membrane transporter and discuss the implications for potential alternative resistance mechanisms in other organisms such as plants.

  19. Selective endothelial overexpression of arginase II induces endothelial dysfunction and hypertension and enhances atherosclerosis in mice.

    Directory of Open Access Journals (Sweden)

    Boris L Vaisman

    Full Text Available Cardiovascular disorders associated with endothelial dysfunction, such as atherosclerosis, have decreased nitric oxide (NO bioavailability. Arginase in the vasculature can compete with eNOS for L-arginine and has been implicated in atherosclerosis. The aim of this study was to evaluate the effect of endothelial-specific elevation of arginase II expression on endothelial function and the development of atherosclerosis.Transgenic mice on a C57BL/6 background with endothelial-specific overexpression of human arginase II (hArgII gene under the control of the Tie2 promoter were produced. The hArgII mice had elevated tissue arginase activity except in liver and in resident peritoneal macrophages, confirming endothelial specificity of the transgene. Using small-vessel myography, aorta from these mice exhibited endothelial dysfunction when compared to their non-transgenic littermate controls. The blood pressure of the hArgII mice was 17% higher than their littermate controls and, when crossed with apoE -/- mice, hArgII mice had increased aortic atherosclerotic lesions.We conclude that overexpression of arginase II in the endothelium is detrimental to the cardiovascular system.

  20. Enhanced negative chronotropy by inhibitory receptors in transgenic heart overexpressing beta(2)-adrenoceptors.

    Science.gov (United States)

    Du, X J; Vincan, E; Percy, E; Woodcock, E A

    2000-03-15

    Transgenic (TG) mice overexpressing beta(2)-adrenoceptors (AR) in the heart have enhanced beta-adrenergic activity. Since the degree of beta-adrenergic activation influences the negative chronotropic control of heart rate (HR), we studied the inhibitory effect of cholinergic and purinergic stimulation on HR in TG and wild-type (WT) control mice. Bradycardia in response to vagal nerve stimulation and administration of acetylcholine or adenosine was studied in anesthetised animals and perfused hearts. Basal HR was significantly higher in TG than WT mice (P<0.01). Electrical stimulation of vagal nerves (1-32 Hz) induced a Hz-dependent reduction in HR and the response was more pronounced in TG than WT groups (P<0.01). In perfused hearts, HR reduction by acetylcholine (ACh) was more pronounced with EC(50) 110-fold lower in TG than WT hearts. Adenosine-induced bradycardia, which was abolished by a P(1) antagonist, was more pronounced in TG hearts. After pre-treatment with pertussis toxin (PT, 100 microg/kg), bradycardia by vagal nerve stimulation or ACh remained unchanged in WT, but markedly inhibited in TG hearts (both P<0.01). Conversely, inhibiting guanylyl cyclase with LY83583 (30 microM) or nitric oxide synthase with L-NMMA (100 microM) attenuated HR reduction by vagal nerve stimulation in WT but not in TG hearts. Immunobloting assay showed similar G(ialpha2) abundance in TG and WT hearts. Thus, cardiac overexpression of beta(2)AR with high beta-adrenergic activity leads to hypersensitivity of inhibitory receptors controlling HR due to increase in activity of PT-sensitive G-proteins.

  1. Over-expression of tetraspanin 8 in malignant glioma regulates tumor cell progression

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Si-Jian [Department of Neurosurgery, Rui Jin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200025 (China); Wu, Yue-Bing [Department of Internal Medicine Oncology, Hubei Cancer Hospital, Wuhan, Hubei 430079 (China); Cai, Shang [Department of Radiotherapy and Oncology, the Second Affiliated Hospital of Soochow University, Suzhou 21500 (China); Pan, Yi-Xin; Liu, Wei [Department of Stereotactic and Functional Neurosurgery, Rui Jin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025 (China); Bian, Liu-Guan [Department of Neurosurgery, Rui Jin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200025 (China); Sun, Bomin [Department of Stereotactic and Functional Neurosurgery, Rui Jin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025 (China); Sun, Qing-Fang, E-mail: sunqingfang11@163.com [Department of Neurosurgery, Rui Jin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200025 (China)

    2015-03-13

    Tumor cell invasion and proliferation remain the overwhelming causes of death for malignant glioma patients. To establish effective therapeutic methods, new targets implied in these processes have to be identified. Tetraspanin 8 (Tspn8) forms complexes with a large variety of trans-membrane and/or cytosolic proteins to regulate several important cellular functions. In the current study, we found that Tspn8 was over-expressed in multiple clinical malignant glioma tissues, and its expression level correlated with the grade of tumors. Tspn8 expression in malignant glioma cells (U251MG and U87MG lines) is important for cell proliferation and migration. siRNA-mediated knockdown of Tspn8 markedly reduced in vitro proliferation and migration of U251MG and U87MG cells. Meanwhile, Tspn8 silencing also increased the sensitivity of temozolomide (TMZ), and significantly increased U251MG or U87MG cell death and apoptosis by TMZ were achieved with Tspn8 knockdown. We observed that Tspn8 formed a complex with activated focal adhesion kinase (FAK) in both human malignant glioma tissues and in above glioma cells. This complexation appeared required for FAK activation, since Tspn8 knockdown inhibited FAK activation in U251MG and U87MG cells. These results provide evidence that Tspn8 contributes to the pathogenesis of glioblastoma probably by promoting proliferation, migration and TMZ-resistance of glioma cells. Therefore, targeting Tspn8 may provide a potential therapeutic intervention for malignant glioma. - Highlights: • Tspn8 is over-expressed in multiple clinical malignant glioma tissues. • Tspn8 expression is correlated with the grade of malignant gliomas. • Tspn8 knockdown suppresses U251MG/U87MG proliferation and in vitro migration. • Tspn8 knockdown significantly increases TMZ sensitivity in U251MG/U87MG cells. • Tspn8 forms a complex with FAK, required for FAK activation.

  2. BRCA1-IRIS overexpression promotes formation of aggressive breast cancers.

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    Yoshiko Shimizu

    Full Text Available INTRODUCTION: Women with HER2(+ or triple negative/basal-like (TN/BL breast cancers succumb to their cancer rapidly due, in part to acquired Herceptin resistance and lack of TN/BL-targeted therapies. BRCA1-IRIS is a recently discovered, 1399 residue, BRCA1 locus alternative product, which while sharing 1365 residues with the full-length product of this tumor suppressor gene, BRCA1/p220, it has oncoprotein-like properties. Here, we examine whether BRCA1-IRIS is a valuable treatment target for HER2(+ and/or TN/BL tumors. METHODOLOGY/PRINCIPAL FINDINGS: Immunohistochemical staining of large cohort of human breast tumor samples using new monoclonal anti-BRCA1-IRIS antibody, followed by correlation of BRCA1-IRIS expression with that of AKT1, AKT2, p-AKT, survivin and BRCA1/p220, tumor status and age at diagnosis. Generation of subcutaneous tumors in SCID mice using human mammary epithelial (HME cells overexpressing TERT/LT/BRCA1-IRIS, followed by comparing AKT, survivin, and BRCA1/p220 expression, tumor status and aggressiveness in these tumors to that in tumors developed using TERT/LT/Ras(V12-overexpressing HME cells. Induction of primary and invasive rat mammary tumors using the carcinogen N-methyl-N-nitrosourea (NMU, followed by analysis of rat BRCA1-IRIS and ERα mRNA levels in these tumors. High BRCA1-IRIS expression was detected in the majority of human breast tumors analyzed, which was positively correlated with that of AKT1-, AKT2-, p-AKT-, survivin, but negatively with BRCA1/p220 expression. BRCA1-IRIS-positivity induced high-grade, early onset and metastatic HER2(+ or TN/BL tumors. TERT/LT/BRCA1-IRIS overexpressing HME cells formed invasive subcutaneous tumors that express high AKT1, AKT2, p-AKT and vimentin, but no CK19, p63 or BRCA1/p220. NMU-induced primary and invasive rat breast cancers expressed high levels of rat BRCA1-IRIS mRNA but low levels of rat ERα mRNA. CONCLUSION/SIGNIFICANCE: BRCA1-IRIS overexpression triggers aggressive

  3. Overexpression of HDAC6 induces pro-inflammatory responses by regulating ROS-MAPK-NF-κB/AP-1 signaling pathways in macrophages.

    Science.gov (United States)

    Youn, Gi Soo; Lee, Keun Wook; Choi, Soo Young; Park, Jinseu

    2016-08-01

    Although histone deacetylase 6 (HDAC6) has been implicated in inflammatory diseases, direct involvement and its action mechanism of HDAC6 in the transcriptional regulation of pro-inflammatory genes have been unclear. In this study, we investigated the possible role of HDAC6 in the expression of pro-inflammatory mediators, indicator of macrophage activation, in RAW 264.7 cells and primary mouse macrophages. HDAC6 overexpression significantly enhanced expression of pro-inflammatory cytokines, such as TNF-α, IL-1β, and IL-6, with concomitant reduction in acetylated α-tubulin. HDAC6 overexpression significantly induced ROS generation via upregulation of NADPH oxidase expression and activity. Inhibition of ROS generation by N-acetyl cysteine, diphenyl iodonium and apocynin suppressed HDAC6-induced pro-inflammatory cytokines. An HDAC6 enzymatic inhibitor significantly inhibited ROS generation and expression of HDAC6-induced pro-inflammatory mediators, indicating the requirement of HDAC6 enzymatic activity for induction of pro-inflammatory cytokines. In addition, HDAC6 overexpression increased activation of MAPK species including ERK, JNK, and p38. Furthermore, HDAC6 overexpression resulted in activation of the NF-κB and AP-1 signaling pathways. Overall, our results provide the first evidence that HDAC6 is capable of inducing expression of pro-inflammatory genes by regulating the ROS-MAPK-NF-κB/AP-1 pathways and serves as a molecular target for inflammation.

  4. Serotonin accumulation in transgenic rice by over-expressing tryptophan decarboxylase results in a dark brown phenotype and stunted growth.

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    Kanjanaphachoat, Parawee; Wei, Bi-Yin; Lo, Shuen-Fang; Wang, I-Wen; Wang, Chang-Sheng; Yu, Su-May; Yen, Ming-Liang; Chiu, Sheng-Hsien; Lai, Chien-Chen; Chen, Liang-Jwu

    2012-04-01

    A mutant M47286 with a stunted growth, low fertility and dark-brown phenotype was identified from a T-DNA-tagged rice mutant library. This mutant contained a copy of the T-DNA tag inserted at the location where the expression of two putative tryptophan decarboxylase genes, TDC-1 and TDC-3, were activated. Enzymatic assays of both recombinant proteins showed tryptophan decarboxylase activities that converted tryptophan to tryptamine, which could be converted to serotonin by a constitutively expressed tryptamine 5' hydroxylase (T5H) in rice plants. Over-expression of TDC-1 and TDC-3 in transgenic rice recapitulated the stunted growth, darkbrown phenotype and resulted in a low fertility similar to M47286. The degree of stunted growth and dark-brown color was proportional to the expression levels of TDC-1 and TDC-3. The levels of tryptamine and serotonin accumulation in these transgenic rice lines were also directly correlated with the expression levels of TDC-1 and TDC-3. A mass spectrometry assay demonstrated that the darkbrown leaves and hulls in the TDC-overexpressing transgenic rice were caused by the accumulation of serotonin dimer and that the stunted growth and low fertility were also caused by the accumulation of serotonin and serotonin dimer, but not tryptamine. These results represent the first evidence that over-expression of TDC results in stunted growth, low fertility and the accumulation of serotonin, which when converted to serotonin dimer, leads to a dark brown plant color.

  5. Local overexpression of Su(H-MAPK variants affects Notch target gene expression and adult phenotypes in Drosophila

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    Jasmin S. Auer

    2015-12-01

    Here we address the consequences of a local induction of three Su(H variants on Notch target gene expression. To this end, wild-type Su(H, a phospho-deficient Su(HMAPK-ko and a phospho-mimetic Su(HMAPK-ac isoform were overexpressed in the central domain of the wing anlagen. The expression of the Notch target genes cut, wingless, E(splm8-HLH and vestigial, was monitored. For the latter two, reporter genes were used (E(splm8-lacZ, vgBE-lacZ. In general, Su(HMAPK-ko induced a stronger response than wild-type Su(H, whereas the response to Su(HMAPK-ac was very weak. Notch target genes cut, wingless and vgBE-lacZ were ectopically activated, whereas E(splm8-lacZ was repressed by overexpression of Su(H proteins. In addition, in epistasis experiments an activated form of the EGF-receptor (DERact or the MAPK (rlSEM and individual Su(H variants were co-overexpressed locally, to compare the resultant phenotypes in adult flies (thorax, wings and eyes as well as to assay the response of the Notch target gene cut in cell clones.

  6. SOD1 Overexpression Preserves Baroreflex Control of Heart Rate with an Increase of Aortic Depressor Nerve Function

    Science.gov (United States)

    Hatcher, Jeffrey; Gu, He; Cheng, Zixi (Jack)

    2016-01-01

    Overproduction of reactive oxygen species (ROS), such as the superoxide radical (O2∙−), is associated with diseases which compromise cardiac autonomic function. Overexpression of SOD1 may offer protection against ROS damage to the cardiac autonomic nervous system, but reductions of O2∙− may interfere with normal cellular functions. We have selected the C57B6SJL-Tg (SOD1)2 Gur/J mouse as a model to determine whether SOD1 overexpression alters cardiac autonomic function, as measured by baroreflex sensitivity (BRS) and aortic depressor nerve (ADN) recordings, as well as evaluation of baseline heart rate (HR) and mean arterial pressure (MAP). Under isoflurane anesthesia, C57 wild-type and SOD1 mice were catheterized with an arterial pressure transducer and measurements of HR and MAP were taken. After establishing a baseline, hypotension and hypertension were induced by injection of sodium nitroprusside (SNP) and phenylephrine (PE), respectively, and ΔHR versus ΔMAP were recorded as a measure of baroreflex sensitivity (BRS). SNP and PE treatment were administered sequentially after a recovery period to measure arterial baroreceptor activation by recording aortic depressor nerve activity. Our findings show that overexpression of SOD1 in C57B6SJL-Tg (SOD1)2 Gur/J mouse preserved the normal HR, MAP, and BRS but enhanced aortic depressor nerve function. PMID:26823951

  7. Hydrogen-producing Escherichia coli strains overexpressing lactose permease: FT-IR analysis of the lactose-induced stress.

    Science.gov (United States)

    Grube, Mara; Dimanta, Ilze; Gavare, Marita; Strazdina, Inese; Liepins, Janis; Juhna, Talis; Kalnenieks, Uldis

    2014-01-01

    The lactose permease gene (lacY) was overexpressed in the septuple knockout mutant of Escherichia coli, previously engineered for hydrogen production from glucose. It was expected that raising the lactose transporter activity would elevate the intracellular lactose concentration, inactivate the lactose repressor, induce the lactose operon, and as a result stimulate overall lactose consumption and conversion. However, overexpression of the lactose transporter caused a considerable growth delay in the recombinant strain on lactose, resembling to some extent the "lactose killing" phenomenon. Therefore, the recombinant strain was subjected to selection on lactose-containing media. Selection on plates with 3% lactose yielded a strain with a decreased content of the recombinant plasmid but with an improved ability to grow and produce hydrogen on lactose. Macromolecular analysis of its biomass by means of Fourier transform-infrared spectroscopy demonstrated that increase of the cellular polysaccharide content might contribute to the adaptation of E. coli to lactose stress.

  8. Striatal adenosine-cannabinoid receptor interactions in rats over-expressing adenosine A2A receptors.

    Science.gov (United States)

    Chiodi, Valentina; Ferrante, Antonella; Ferraro, Luca; Potenza, Rosa Luisa; Armida, Monica; Beggiato, Sarah; Pèzzola, Antonella; Bader, Michael; Fuxe, Kjell; Popoli, Patrizia; Domenici, Maria Rosaria

    2016-03-01

    Adenosine A2A receptors (A2 A Rs) and cannabinoid CB1 receptors (CB1 Rs) are highly expressed in the striatum, where they functionally interact and form A2A /CB1 heteroreceptor complexes. We investigated the effects of CB1 R stimulation in a transgenic rat strain over-expressing A2 A Rs under the control of the neural-specific enolase promoter (NSEA2A rats) and in age-matched wild-type (WT) animals. The effects of the CB1 R agonist WIN 55,212-2 (WIN) were significantly lower in NSEA2A rats than in WT animals, as demonstrated by i) electrophysiological recordings of synaptic transmission in corticostriatal slices; ii) the measurement of glutamate outflow from striatal synaptosomes and iii) in vivo experiments on locomotor activity. Moreover, while the effects of WIN were modulated by both A2 A R agonist (CGS 21680) and antagonists (ZM 241385, KW-6002 and SCH-442416) in WT animals, the A2 A R antagonists failed to influence WIN-mediated effects in NSEA2A rats. The present results demonstrate that in rats with genetic neuronal over-expression of A2 A Rs, the effects mediated by CB1 R activation in the striatum are significantly reduced, suggesting a change in the stoichiometry of A2A and CB1 receptors and providing a strategy to dissect the involvement of A2 A R forming or not forming heteromers in the modulation of striatal functions. These findings add additional evidence for the existence of an interaction between striatal A2 A Rs and CB1 Rs, playing a fundamental role in the regulation of striatal functions. We studied A2A -CB1 receptor interaction in transgenic rats over-expressing adenosine A2A receptors under the control of the neuron-specific enolase promoter (NSEA2A ). In these rats, we demonstrated a reduced effect of the CB1 receptor agonist WIN 55,212-2 in the modulation of corticostriatal synaptic transmission and locomotor activity, while CB1 receptor expression level did not change with respect to WT rats. A reduction in the expression of A2A -CB1

  9. Overexpression of Indian hedgehog partially rescues short stature homeobox 2-overexpression-associated congenital dysplasia of the temporomandibular joint in mice.

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    Li, Xihai; Liang, Wenna; Ye, Hongzhi; Weng, Xiaping; Liu, Fayuan; Lin, Pingdong; Liu, Xianxiang

    2015-09-01

    The role of short stature homeobox 2 (shox2) in the development and homeostasis of the temporomandibular joint (TMJ) has been well documented. Shox2 is known to be expressed in the progenitor cells and perichondrium of the developing condyle. A previous study by our group reported that overexpression of shox2 leads to congenital dysplasia of the TMJ via downregulation of the Indian hedgehog (Ihh) signaling pathway, which is essential for embryonic disc primordium formation and mandibular condylar growth. To determine whether overexpression of Ihh may rescue the overexpression of shox2 leading to congenital dysplasia of the TMJ, a mouse model in which Ihh and shox2 were overexpressed (Wnt1-Cre; pMes-stop shox2; pMes-stop Ihh mice) was utilized to assess the consequences of this overexpression on TMJ development during post-natal life. The results showed that the developmental process and expression levels of runt-related transcription factor 2 and sex determining region Y-box 9 in the TMJ of the Wnt1-Cre; pMes-stop shox2; pMes-stop Ihh mice were similar to those in wild‑type mice. Overexpression of Ihh rescued shox2 overexpression-associated reduction of extracellular matrix components. However, overexpression of Ihh did not inhibit the shox2 overexpression-associated increase of matrix metalloproteinases (MMPs) MMP9, MMP13 and apoptosis in the TMJ. These combinatory cellular and molecular defects appeared to account for the observed congenital dysplasia of TMJ, suggesting that overexpression of Ihh partially rescued shox2 overexpression‑associated congenital dysplasia of the TMJ in mice.

  10. Overexpression of glutamine synthetases confers transgenic rice herbicide resistance

    Institute of Scientific and Technical Information of China (English)

    Sun Hui; Huang Qiman; Su Jin

    2005-01-01

    Glutamine synthetase (GS, E.C.6.3.1.2) is a key enzyme involved in the assimilation of inorganic nitrogen in higher plants and gram-negative microorganisms. GS is the targeting enzyme of a herbicide phosphinothricin (PPT) or Basta. In order to generate PPT-resistant transgenic rice via overexpression of GS, we constructed a plant expression vector p2GS harboring two different isoenzymes GS1 and GS2 cDNAs under the control of constitutive promoters of rice Act1 and maize Ubiquitin(Ubi) genes. The p2GS was introduced into rice genome by Agrobacterium-mediated transformation and confirmed by PCR and Southern blot hybridization. GS-transgene expression was first detected by Northern blot analyses. Results from Basta test indicated that GS-transgenic plants can tolerate as high as 0.3% Basta solution. In addition, our results also demonstrated that GS overexpression conferred transformed rice calli PPT resistance. Thus, GS cassette can serve as a selective marker gene instead of bar cassette for selection of PPT transformants.

  11. Over-expression of EGFR in Breast Cancer

    Institute of Scientific and Technical Information of China (English)

    BO Ai-hua; HOU Jin-chao; LAN Yong-hao; TIAN Ya-ting; ZHANG Jun-yan

    2008-01-01

    Objective:To explore the relationship of overexpression of epidermal growth factor receptor(EGFR)in occurrence,development and treatment of breast cancer. Methods:Samples of 46 breast adenoma tissues and 86 breast cancer tissues were regularly dehydrate-fixed,embedded in paraffin,sliced in to 5 μm thick,stained with SABC immunohistochemistry and coloured with DAB. Results:The positive staining of EGFR was shown as brown- yellow and distributed in cytoplasm.The positive rates in the tissues of breast adenosis and breast cancer were 17.04%(6/46)and 56.98%(49/86)respectively.The positive rates of EGFR in the tissue of invasive ductal carcinoma was 64.49%(41/59),which was significantly higher than that in in situ carcinoma(P<0.05).The positive rate of lymph metastasis group was higher than that in non-lymph metastasis group (P<0.05). Conclusion:The overexpression of EGFR was related with occurrence,lymph metastasis and pathologic types of breast cancer.The examination of EGFR in the breast cancer can serve as a guidance for target chemotherapy.

  12. Overexpression of neurofilament H disrupts normal cell structure and function

    Science.gov (United States)

    Szebenyi, Gyorgyi; Smith, George M.; Li, Ping; Brady, Scott T.

    2002-01-01

    Studying exogenously expressed tagged proteins in live cells has become a standard technique for evaluating protein distribution and function. Typically, expression levels of experimentally introduced proteins are not regulated, and high levels are often preferred to facilitate detection. However, overexpression of many proteins leads to mislocalization and pathologies. Therefore, for normative studies, moderate levels of expression may be more suitable. To understand better the dynamics of intermediate filament formation, transport, and stability in a healthy, living cell, we inserted neurofilament heavy chain (NFH)-green fluorescent protein (GFP) fusion constructs in adenoviral vectors with tetracycline (tet)-regulated promoters. This system allows for turning on or off the synthesis of NFH-GFP at a selected time, for a defined period, in a dose-dependent manner. We used this inducible system for live cell imaging of changes in filament structure and cell shape, motility, and transport associated with increasing NFH-GFP expression. Cells with low to intermediate levels of NFH-GFP were structurally and functionally similar to neighboring, nonexpressing cells. In contrast, overexpression led to pathological alterations in both filament organization and cell function. Copyright 2002 Wiley-Liss, Inc.

  13. Overexpression of Catalase Diminishes Oxidative Cysteine Modifications of Cardiac Proteins.

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    Chunxiang Yao

    Full Text Available Reactive protein cysteine thiolates are instrumental in redox regulation. Oxidants, such as hydrogen peroxide (H2O2, react with thiolates to form oxidative post-translational modifications, enabling physiological redox signaling. Cardiac disease and aging are associated with oxidative stress which can impair redox signaling by altering essential cysteine thiolates. We previously found that cardiac-specific overexpression of catalase (Cat, an enzyme that detoxifies excess H2O2, protected from oxidative stress and delayed cardiac aging in mice. Using redox proteomics and systems biology, we sought to identify the cysteines that could play a key role in cardiac disease and aging. With a 'Tandem Mass Tag' (TMT labeling strategy and mass spectrometry, we investigated differential reversible cysteine oxidation in the cardiac proteome of wild type and Cat transgenic (Tg mice. Reversible cysteine oxidation was measured as thiol occupancy, the ratio of total available versus reversibly oxidized cysteine thiols. Catalase overexpression globally decreased thiol occupancy by ≥1.3 fold in 82 proteins, including numerous mitochondrial and contractile proteins. Systems biology analysis assigned the majority of proteins with differentially modified thiols in Cat Tg mice to pathways of aging and cardiac disease, including cellular stress response, proteostasis, and apoptosis. In addition, Cat Tg mice exhibited diminished protein glutathione adducts and decreased H2O2 production from mitochondrial complex I and II, suggesting improved function of cardiac mitochondria. In conclusion, our data suggest that catalase may alleviate cardiac disease and aging by moderating global protein cysteine thiol oxidation.

  14. Over-expression of AtPAP2 in Camelina sativa leads to faster plant growth and higher seed yield

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    Zhang Youjun

    2012-04-01

    Full Text Available Abstract Background Lipids extracted from seeds of Camelina sativa have been successfully used as a reliable source of aviation biofuels. This biofuel is environmentally friendly because the drought resistance, frost tolerance and low fertilizer requirement of Camelina sativa allow it to grow on marginal lands. Improving the species growth and seed yield by genetic engineering is therefore a target for the biofuels industry. In Arabidopsis, overexpression of purple acid phosphatase 2 encoded by Arabidopsis (AtPAP2 promotes plant growth by modulating carbon metabolism. Overexpression lines bolt earlier and produce 50% more seeds per plant than wild type. In this study, we explored the effects of overexpressing AtPAP2 in Camelina sativa. Results Under controlled environmental conditions, overexpression of AtPAP2 in Camelina sativa resulted in longer hypocotyls, earlier flowering, faster growth rate, higher photosynthetic rate and stomatal conductance, increased seed yield and seed size in comparison with the wild-type line and null-lines. Similar to transgenic Arabidopsis, activity of sucrose phosphate synthase in leaves of transgenic Camelina was also significantly up-regulated. Sucrose produced in photosynthetic tissues supplies the building blocks for cellulose, starch and lipids for growth and fuel for anabolic metabolism. Changes in carbon flow and sink/source activities in transgenic lines may affect floral, architectural, and reproductive traits of plants. Conclusions Lipids extracted from the seeds of Camelina sativa have been used as a major constituent of aviation biofuels. The improved growth rate and seed yield of transgenic Camelina under controlled environmental conditions have the potential to boost oil yield on an area basis in field conditions and thus make Camelina-based biofuels more environmentally friendly and economically attractive.

  15. Mitogenic signaling pathways in the liver of growth hormone (GH)-overexpressing mice during the growth period.

    Science.gov (United States)

    Martinez, Carolina S; Piazza, Verónica G; González, Lorena; Fang, Yimin; Bartke, Andrzej; Turynl, Danie; Miquet, Johanna G; Sotelo, Ana I

    2016-01-01

    Growth hormone (GH) is a pleiotropic hormone that triggers STATs, ERK1/2 and Akt signaling, related to cell growth and proliferation. Transgenic mice overexpressing GH present increased body size, with a disproportionate liver enlargement due to hypertrophy and hyperplasia of the hepatocytes. We had described enhanced mitogenic signaling in liver of young adult transgenic mice. We now evaluate the activation of these signaling cascades during the growth period and relate them to the morphological alterations found. Signaling mediators, cell cycle regulators and transcription factors involved in cellular growth in the liver of GH-overexpressing growing mice were assessed by immunoblotting, RT-qPCR and immunohistochemistry. Hepatocyte enlargement can be seen as early as 2-weeks of age in GH-overexpressing animals, although it is more pronounced in young adults. Levels of cell cycle mediators PCNA and cyclin D1, and transcription factor c-Jun increase with age in transgenic mice with no changes in normal mice, whereas c-Myc levels are higher in 2-week-old transgenic animals and cyclin E levels decline with age for both genotypes. STAT3, Akt and GSK3 present higher activation in the adult transgenic mice than in the growing animals, while for c-Src and mTOR, phosphorylation in GH-overexpressing mice is higher than in control siblings at 4 and 9 weeks of age. No significant changes are observed for ERK1/2, neither by age or genotype. Thus, the majority of the mitogenic signaling pathways are gradually up-regulated in the liver of GH-transgenic mice, giving rise to the hepatic morphological changes these mice exhibit.

  16. Metabolic hormone FGF21 is induced in ground squirrels during hibernation but its overexpression is not sufficient to cause torpor.

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    Bethany T Nelson

    Full Text Available Hibernation is a natural adaptation that allows certain mammals to survive physiological extremes that are lethal to humans. Near freezing body temperatures, heart rates of 3-10 beats per minute, absence of food consumption, and depressed metabolism are characteristic of hibernation torpor bouts that are periodically interrupted by brief interbout arousals (IBAs. The molecular basis of torpor induction is unknown, however starved mice overexpressing the metabolic hormone fibroblast growth factor 21 (FGF21 promote fat utilization, reduce body temperature, and readily enter torpor-all hallmarks of mammalian hibernation. In this study we cloned FGF21 from the naturally hibernating thirteen-lined ground squirrel (Ictidomys tridecemlineatus and found that levels of FGF21 mRNA in liver and FGF21 protein in serum are elevated during hibernation torpor bouts and significantly elevated during IBAs compared to summer active animals. The effects of artificially elevating circulating FGF21 concentrations 50 to 100-fold via adenoviral-mediated overexpression were examined at three different times of the year. This is the first time that a transgenic approach has been used in a natural hibernator to examine mechanistic aspects of hibernation. Surgically implanted transmitters measured various metrics of the hibernation phenotype over a 7-day period including changes in motor activity, heart rate and core body temperature. In April fed-state animals, FGF21 overexpression decreased blood insulin and free fatty acid concentrations, effects similar to those seen in obese mice. However, elevated FGF21 concentrations did not cause torpor in these fed-state animals nor did they cause torpor or affect metabolic parameters in fasted-state animals in March/April, August or October. We conclude that FGF21 is strongly regulated during torpor and IBA but that its overexpression is not sufficient to cause torpor in naturally hibernating ground squirrels.

  17. Overexpression of ERβ is sufficient to inhibit hypoxia-inducible factor-1 transactivation

    Energy Technology Data Exchange (ETDEWEB)

    Park, Choa; Lee, YoungJoo, E-mail: yjlee@sejong.ac.kr

    2014-07-18

    Highlights: • We examined the effect of ERβ specific ligand on HIF-1 inhibition. • DPN down-regulates the ARNT protein levels in PC3 cells. • DPN did not show additional effect in ERβ transfected MCF-7 cells. • Our study shows that unliganded ERβ is sufficient to inhibit HIF-1 in systems of overexpression. - Abstract: Estrogen receptor (ER) β is predicted to play an important role in the prevention of breast cancer development and progression. We have previously shown that ERβ suppresses hypoxia inducible factor (HIF)-1-mediated transcription through aryl hydrocarbon receptor nuclear translocator (ARNT) degradation via ubiquitination processes. In this study, we attempted to examine the effect of ERβ specific ligand on HIF-1 inhibition in ERβ positive PC3 cells and ERβ transfected MCF-7 cells. ERβ specific agonist diarylpropionitrile (DPN) stimulated estrogen response element (ERE)-luciferase activity in a similar fashion to estradiol in PC3 cells. We observed that DPN down-regulates the ARNT protein levels leading to an attenuation of hypoxia-induced hypoxia response element (HRE)-driven luciferase reporter gene activation in PC3 cells. Treatment of DPN reduced vascular endothelial growth factor (VEGF) expression and co-treatment with ERβ specific antagonist PHTPP abrogated the effect in PC3 cells. We then examined the effect of DPN in ERβ transfected MCF-7 cells. HIF-1 transcriptional activity repression by ERβ was not further reduced by DPN, as examined by HRE-driven luciferase assays. Expression of ERβ significantly decreased VEGF secretion and ARNT expression under hypoxic conditions. However, DPN did not additionally affect this suppression in MCF-7 cells transfected with ERβ. This result shows that unliganded ERβ is sufficient to inhibit HIF-1 in systems of overexpression.

  18. Muscle cell atrophy induced by HSP gene silencing was counteracted by HSP overexpression

    Science.gov (United States)

    Choi, Inho; Lee, Joo-Hee; Nikawa, Takeshi; Gwag, Taesik; Park, Kyoungsook; Park, Junsoo

    Heat shock proteins (HSP), as molecular chaperones, are known to assist protein quality control under various stresses. Although overexpression of HSP70 was found to contribute to muscle size retention under an unloading condition, it remains largely unclarified whether muscle atrophy is induced by active suppression of HSP expression. In this study, we pre-treated Hsp70 siRNA to rat L6 cells for the HSP gene silencing, and determined myotube diameter, HSP72 expression and anabolic and catabolic signaling activities in the absence or presence of triterpene celastrol (CEL), the HSP70 inducer. Relative to a negative control (NC), muscle cell diameter was reduced 0.89-fold in the siRNA-treated group, increased 1.2-fold in the CEL-treated group and retained at the size of NC in the siRNA+CEL group. HSP72 expression was decreased 0.35-fold by siRNA whereas the level was increased 6- to 8-fold in the CEL and siRNA+CEL groups. Expression of FoxO3 and atrogin-1 was increased 1.8- to 4.8-fold by siRNA, which was abolished by CEL treatment. Finally, phosphorylation of Akt1, S6K and ERK1/2 was not affected by siRNA, but was elevated 2- to 6-fold in the CEL and siRNA+CEL groups. Taken together, HSP downregulation by Hsp gene silencing led to muscle cell atrophy principally via increases in catabolic activities and that such anti-atrophic effect was counteracted by HSP overexpression.

  19. Overexpression of insulin-like growth factor-II induces accelerated myoblast differentiation.

    Science.gov (United States)

    Stewart, C E; James, P L; Fant, M E; Rotwein, P

    1996-10-01

    Previous studies have shown that exogenous insulin-like growth factors (IGFs) can stimulate the terminal differentiation of skeletal myoblasts in culture and have established a correlation between the rate and the extent of IGF-II secretion by muscle cell lines and the rate of biochemical and morphological differentiation. To investigate the hypothesis that autocrine secretion of IGF-II plays a critical role in stimulating spontaneous myogenic differentiation in vitro, we have established C2 muscle cell lines that stably express a mouse IGF-II cDNA under control of the strong, constitutively active Moloney sarcoma virus promoter, enabling us to study directly the effects of IGF-II overproduction. Similar to observations with other muscle cell lines, IGF-II overexpressing myoblasts proliferated normally in growth medium containing 20% fetal serum, but they underwent enhanced differentiation compared with controls when incubated in low-serum differentiation medium. Accelerated differentiation of IGF-II overexpressing C2 cells was preceded by the rapid induction of myogenin mRNA and protein expression (within 1 h, compared with 24-48 h in controls) and was accompanied by an enhanced proportion