131 research outputs found

    The expression of thymidine phosphorylase correlates with angiogenesis and the efficacy of chemotherapy using fluorouracil derivatives in advanced gastric carcinoma

    Get PDF
    The expression of thymidine phosphorylase (TP) and the density of microvessel in advanced gastric carcinoma were examined by immunohistochemistry to evaluate the significance of TP. The expression of TP was negative in 72 cases, positive in 54. The microvessel density correlated with the expression of TP. In total cases, patients with TP-positive tumours survived longer than those with TP-negative tumours. In patients treated with fluorouracil derivatives (FUs), the expression of TP significantly correlated with favourable prognosis and with unfavourable prognosis in those not treated with FUs. The patients with TP-positive tumours, the prognosis of patients treated with FUs was significantly better than that of those not treated with FUs. In patients with TP-positive tumours, treatment with FUs and lymph node metastasis were independent prognostic factors according to the Cox proportional hazards model. Depth of invasion and lymph node metastasis were independent prognostic factors in patients with TP-negative tumours. The determination of the expression of TP might be useful for predicting the efficacy of post-operative chemotherapy using FUs to prevent recurrence in advanced gastric carcinoma patients who undergo curative gastrectomy. © 1999 Cancer Research Campaig

    Total Aortic Arch Replacement: Superior Ventriculo-Arterial Coupling with Decellularized Allografts Compared with Conventional Prostheses.

    Get PDF
    BACKGROUND: To date, no experimental or clinical study provides detailed analysis of vascular impedance changes after total aortic arch replacement. This study investigated ventriculoarterial coupling and vascular impedance after replacement of the aortic arch with conventional prostheses vs. decellularized allografts. METHODS: After preparing decellularized aortic arch allografts, their mechanical, histological and biochemical properties were evaluated and compared to native aortic arches and conventional prostheses in vitro. In open-chest dogs, total aortic arch replacement was performed with conventional prostheses and compared to decellularized allografts (n = 5/group). Aortic flow and pressure were recorded continuously, left ventricular pressure-volume relations were measured by using a pressure-conductance catheter. From the hemodynamic variables end-systolic elastance (Ees), arterial elastance (Ea) and ventriculoarterial coupling were calculated. Characteristic impedance (Z) was assessed by Fourier analysis. RESULTS: While Ees did not differ between the groups and over time (4.1+/-1.19 vs. 4.58+/-1.39 mmHg/mL and 3.21+/-0.97 vs. 3.96+/-1.16 mmHg/mL), Ea showed a higher increase in the prosthesis group (4.01+/-0.67 vs. 6.18+/-0.20 mmHg/mL, P<0.05) in comparison to decellularized allografts (5.03+/-0.35 vs. 5.99+/-1.09 mmHg/mL). This led to impaired ventriculoarterial coupling in the prosthesis group, while it remained unchanged in the allograft group (62.5+/-50.9 vs. 3.9+/-23.4%). Z showed a strong increasing tendency in the prosthesis group and it was markedly higher after replacement when compared to decellularized allografts (44.6+/-8.3dyn.sec.cm-5 vs. 32.4+/-2.0dyn.sec.cm-5, P<0.05). CONCLUSIONS: Total aortic arch replacement leads to contractility-afterload mismatch by means of increased impedance and invert ventriculoarterial coupling ratio after implantation of conventional prostheses. Implantation of decellularized allografts preserves vascular impedance thereby improving ventriculoarterial mechanoenergetics after aortic arch replacement

    Cyr61/CCN1 Is Regulated by Wnt/β-Catenin Signaling and Plays an Important Role in the Progression of Hepatocellular Carcinoma

    Get PDF
    Abnormal activation of the canonical Wnt signaling pathway has been implicated in carcinogenesis. Transcription of Wnt target genes is regulated by nuclear β-catenin, whose over-expression is observed in Hepatocellular Carcinoma (HCC) tissue. Cyr61, a member of the CCN complex family of multifunctional proteins, is also found over-expressed in many types of tumor and plays dramatically different roles in tumorigenesis. In this study, we investigated the relationship between Cyr61 and β-catenin in HCC. We found that while Cyr61 protein was not expressed at a detectable level in the liver tissue of healthy individuals, its expression level was elevated in the HCC and HCC adjacent tissues and was markedly increased in cancer-adjacent hepatic cirrhosis tissue. Over-expression of Cyr61 was positively correlated with increased levels of β-catenin in human HCC samples. Activation of β-catenin signaling elevated the mRNA level of Cyr61 in HepG2 cells, while inhibition of β-catenin signaling reduced both mRNA and protein levels of Cyr61. We identified two TCF4-binding elements in the promoter region of human Cyr61 gene and demonstrated that β-catenin/TCF4 complex specifically bound to the Cyr61 promoter in vivo and directly regulated its promoter activity. Furthermore, we found that over-expression of Cyr61 in HepG2 cells promoted the progression of HCC xenografts in SCID mice. These findings indicate that Cyr61 is a direct target of β-catenin signaling in HCC and may play an important role in the progression of HCC

    Ask yeast how to burn your fats: lessons learned from the metabolic adaptation to salt stress

    Full text link
    [EN] Here, we review and update the recent advances in the metabolic control during the adaptive response of budding yeast to hyperosmotic and salt stress, which is one of the best understood signaling events at the molecular level. This environmental stress can be easily applied and hence has been exploited in the past to generate an impressively detailed and comprehensive model of cellular adaptation. It is clear now that this stress modulates a great number of different physiological functions of the cell, which altogether contribute to cellular survival and adaptation. Primary defense mechanisms are the massive induction of stress tolerance genes in the nucleus, the activation of cation transport at the plasma membrane, or the production and intracellular accumulation of osmolytes. At the same time and in a coordinated manner, the cell shuts down the expression of housekeeping genes, delays the progression of the cell cycle, inhibits genomic replication, and modulates translation efficiency to optimize the response and to avoid cellular damage. To this fascinating interplay of cellular functions directly regulated by the stress, we have to add yet another layer of control, which is physiologically relevant for stress tolerance. Salt stress induces an immediate metabolic readjustment, which includes the up-regulation of peroxisomal biomass and activity in a coordinated manner with the reinforcement of mitochondrial respiratory metabolism. Our recent findings are consistent with a model, where salt stress triggers a metabolic shift from fermentation to respiration fueled by the enhanced peroxisomal oxidation of fatty acids. We discuss here the regulatory details of this stress-induced metabolic shift and its possible roles in the context of the previously known adaptive functions.The work of the authors was supported by grants from Ministerio de Economía y Competitividad (BFU2011- 23326 and BFU2016-75792-R).Pascual-Ahuir Giner, MD.; Manzanares-Estreder, S.; Timón Gómez, A.; Proft ., MH. (2017). Ask yeast how to burn your fats: lessons learned from the metabolic adaptation to salt stress. Current Genetics. 64(1):63-69. https://doi.org/10.1007/s00294-017-0724-5S6369641Aguilera J, Prieto JA (2001) The Saccharomyces cerevisiae aldose reductase is implied in the metabolism of methylglyoxal in response to stress conditions. Curr Genet 39:273–283Albertyn J, Hohmann S, Thevelein JM, Prior BA (1994) GPD1, which encodes glycerol-3-phosphate dehydrogenase, is essential for growth under osmotic stress in Saccharomyces cerevisiae, and its expression is regulated by the high-osmolarity glycerol response pathway. Mol Cell Biol 14:4135–4144Alepuz PM, Jovanovic A, Reiser V, Ammerer G (2001) Stress-induced map kinase Hog1 is part of transcription activation complexes. Mol Cell 7:767–777Alepuz PM, de Nadal E, Zapater M, Ammerer G, Posas F (2003) Osmostress-induced transcription by Hot1 depends on a Hog1-mediated recruitment of the RNA Pol II. EMBO J 22:2433–2442Ansell R, Granath K, Hohmann S, Thevelein JM, Adler L (1997) The two isoenzymes for yeast NAD+-dependent glycerol 3-phosphate dehydrogenase encoded by GPD1 and GPD2 have distinct roles in osmoadaptation and redox regulation. EMBO J 16:2179–2187Babazadeh R, Lahtvee PJ, Adiels CB, Goksor M, Nielsen JB, Hohmann S (2017) The yeast osmostress response is carbon source dependent. Sci Rep 7:990Bender T, Pena G, Martinou JC (2015) Regulation of mitochondrial pyruvate uptake by alternative pyruvate carrier complexes. EMBO J 34:911–924Berry DB, Gasch AP (2008) Stress-activated genomic expression changes serve a preparative role for impending stress in yeast. Mol Biol Cell 19:4580–4587Bilsland-Marchesan E, Arino J, Saito H, Sunnerhagen P, Posas F (2000) Rck2 kinase is a substrate for the osmotic stress-activated mitogen-activated protein kinase Hog1. Mol Cell Biol 20:3887–3895Brewster JL, Gustin MC (2014) Hog 1: 20 years of discovery and impact. Sci Signal 7:re7Clotet J, Posas F (2007) Control of cell cycle in response to osmostress: lessons from yeast. Methods Enzymol 428:63–76Clotet J, Escote X, Adrover MA, Yaakov G, Gari E, Aldea M, de Nadal E, Posas F (2006) Phosphorylation of Hsl1 by Hog1 leads to a G2 arrest essential for cell survival at high osmolarity. EMBO J 25:2338–2346Cook KE, O’Shea EK (2012) Hog1 controls global reallocation of RNA Pol II upon osmotic shock in Saccharomyces cerevisiae. Genes Genomes Genetics 2:1129–1136de Nadal E, Posas F (2015) Osmostress-induced gene expression—a model to understand how stress-activated protein kinases (SAPKs) regulate transcription. FEBS J 282:3275–3285de Nadal E, Alepuz PM, Posas F (2002) Dealing with osmostress through MAP kinase activation. EMBO Rep 3:735–740de Nadal E, Casadome L, Posas F (2003) Targeting the MEF2-like transcription factor Smp1 by the stress-activated Hog1 mitogen-activated protein kinase. Mol Cell Biol 23:229–237de Nadal E, Zapater M, Alepuz PM, Sumoy L, Mas G, Posas F (2004) The MAPK Hog1 recruits Rpd3 histone deacetylase to activate osmoresponsive genes. Nature 427:370–374Duch A, de Nadal E, Posas F (2013a) Dealing with transcriptional outbursts during S phase to protect genomic integrity. J Mol Biol 425:4745–4755Duch A, Felipe-Abrio I, Barroso S, Yaakov G, Garcia-Rubio M, Aguilera A, de Nadal E, Posas F (2013b) Coordinated control of replication and transcription by a SAPK protects genomic integrity. Nature 493:116–119Escote X, Zapater M, Clotet J, Posas F (2004) Hog1 mediates cell-cycle arrest in G1 phase by the dual targeting of Sic1. Nat Cell Biol 6:997–1002Ferreira C, van Voorst F, Martins A, Neves L, Oliveira R, Kielland-Brandt MC, Lucas C, Brandt A (2005) A member of the sugar transporter family, Stl1p is the glycerol/H+ symporter in Saccharomyces cerevisiae. Mol Biol Cell 16:2068–2076Gonzalez R, Morales P, Tronchoni J, Cordero-Bueso G, Vaudano E, Quiros M, Novo M, Torres-Perez R, Valero E (2016) New genes involved in osmotic stress tolerance in Saccharomyces cerevisiae. Front Microbiol 7:1545Ho YH, Gasch AP (2015) Exploiting the yeast stress-activated signaling network to inform on stress biology and disease signaling. Curr Genet 61:503–511Hohmann S (2015) An integrated view on a eukaryotic osmoregulation system. Curr Genet 61:373–382Hohmann S, Krantz M, Nordlander B (2007) Yeast osmoregulation. Methods Enzymol 428:29–45Hong SP, Carlson M (2007) Regulation of snf1 protein kinase in response to environmental stress. J Biol Chem 282:16838–16845Li SC, Diakov TT, Rizzo JM, Kane PM (2012) Vacuolar H+-ATPase works in parallel with the HOG pathway to adapt Saccharomyces cerevisiae cells to osmotic stress. Eukaryot Cell 11:282–291Maeta K, Izawa S, Inoue Y (2005) Methylglyoxal, a metabolite derived from glycolysis, functions as a signal initiator of the high osmolarity glycerol-mitogen-activated protein kinase cascade and calcineurin/Crz1-mediated pathway in Saccharomyces cerevisiae. J Biol Chem 280:253–260Manzanares-Estreder S, Espi-Bardisa J, Alarcon B, Pascual-Ahuir A, Proft M (2017) Multilayered control of peroxisomal activity upon salt stress in Saccharomyces cerevisiae. Mol Microbiol 104:851–868Mao K, Wang K, Zhao M, Xu T, Klionsky DJ (2011) Two MAPK-signaling pathways are required for mitophagy in Saccharomyces cerevisiae. J Cell Biol 193:755–767Martinez-Montanes F, Pascual-Ahuir A, Proft M (2010) Toward a genomic view of the gene expression program regulated by osmostress in yeast. OMICS 14:619–627Martinez-Pastor M, Proft M, Pascual-Ahuir A (2010) Adaptive changes of the yeast mitochondrial proteome in response to salt stress. OMICS 14:541–552Mas G, de Nadal E, Dechant R, Rodriguez de la Concepcion ML, Logie C, Jimeno-Gonzalez S, Chavez S, Ammerer G, Posas F (2009) Recruitment of a chromatin remodelling complex by the Hog1 MAP kinase to stress genes. EMBO J 28:326–336Mettetal JT, Muzzey D, Gomez-Uribe C, van Oudenaarden A (2008) The frequency dependence of osmo-adaptation in Saccharomyces cerevisiae. Science 319:482–484Molin C, Jauhiainen A, Warringer J, Nerman O, Sunnerhagen P (2009) mRNA stability changes precede changes in steady-state mRNA amounts during hyperosmotic stress. RNA 15:600–614Nadal-Ribelles M, Conde N, Flores O, Gonzalez-Vallinas J, Eyras E, Orozco M, de Nadal E, Posas F (2012) Hog1 bypasses stress-mediated down-regulation of transcription by RNA polymerase II redistribution and chromatin remodeling. Genome Biol 13:R106Pastor MM, Proft M, Pascual-Ahuir A (2009) Mitochondrial function is an inducible determinant of osmotic stress adaptation in yeast. J Biol Chem 284:30307–30317Petelenz-Kurdziel E, Kuehn C, Nordlander B, Klein D, Hong KK, Jacobson T, Dahl P, Schaber J, Nielsen J, Hohmann S, Klipp E (2013) Quantitative analysis of glycerol accumulation, glycolysis and growth under hyper osmotic stress. PLoS Comput Biol 9:e1003084Posas F, Chambers JR, Heyman JA, Hoeffler JP, de Nadal E, Arino J (2000) The transcriptional response of yeast to saline stress. J Biol Chem 275:17249–17255Proft M, Struhl K (2002) Hog1 kinase converts the Sko1-Cyc8-Tup1 repressor complex into an activator that recruits SAGA and SWI/SNF in response to osmotic stress. Mol Cell 9:1307–1317Proft M, Struhl K (2004) MAP kinase-mediated stress relief that precedes and regulates the timing of transcriptional induction. Cell 118:351–361Proft M, Pascual-Ahuir A, de Nadal E, Arino J, Serrano R, Posas F (2001) Regulation of the Sko1 transcriptional repressor by the Hog1 MAP kinase in response to osmotic stress. EMBO J 20:1123–1133Proft M, Mas G, de Nadal E, Vendrell A, Noriega N, Struhl K, Posas F (2006) The stress-activated Hog1 kinase is a selective transcriptional elongation factor for genes responding to osmotic stress. Mol Cell 23:241–250Ratnakumar S, Young ET (2010) Snf1 dependence of peroxisomal gene expression is mediated by Adr1. J Biol Chem 285:10703–10714Regot S, de Nadal E, Rodriguez-Navarro S, Gonzalez-Novo A, Perez-Fernandez J, Gadal O, Seisenbacher G, Ammerer G, Posas F (2013) The Hog1 stress-activated protein kinase targets nucleoporins to control mRNA export upon stress. J Biol Chem 288:17384–17398Rep M, Krantz M, Thevelein JM, Hohmann S (2000) The transcriptional response of Saccharomyces cerevisiae to osmotic shock. Hot1p and Msn2p/Msn4p are required for the induction of subsets of high osmolarity glycerol pathway-dependent genes. J Biol Chem 275:8290–8300Rep M, Proft M, Remize F, Tamas M, Serrano R, Thevelein JM, Hohmann S (2001) The Saccharomyces cerevisiae Sko1p transcription factor mediates HOG pathway-dependent osmotic regulation of a set of genes encoding enzymes implicated in protection from oxidative damage. Mol Microbiol 40:1067–1083Rienzo A, Poveda-Huertes D, Aydin S, Buchler NE, Pascual-Ahuir A, Proft M (2015) Different mechanisms confer gradual control and memory at nutrient- and stress-regulated genes in yeast. Mol Cell Biol 35:3669–3683Romero-Santacreu L, Moreno J, Perez-Ortin JE, Alepuz P (2009) Specific and global regulation of mRNA stability during osmotic stress in Saccharomyces cerevisiae. RNA 15:1110–1120Roy A, Hashmi S, Li Z, Dement AD, Cho KH, Kim JH (2016) The glucose metabolite methylglyoxal inhibits expression of the glucose transporter genes by inactivating the cell surface glucose sensors Rgt2 and Snf3 in yeast. Mol Biol Cell 27:862–871Ruiz-Roig C, Noriega N, Duch A, Posas F, de Nadal E (2012) The Hog1 SAPK controls the Rtg1/Rtg3 transcriptional complex activity by multiple regulatory mechanisms. Mol Biol Cell 23:4286–4296Saito H, Posas F (2012) Response to hyperosmotic stress. Genetics 192:289–318Sekito T, Thornton J, Butow RA (2000) Mitochondria-to-nuclear signaling is regulated by the subcellular localization of the transcription factors Rtg1p and Rtg3p. Mol Biol Cell 11:2103–2115Silva RD, Sotoca R, Johansson B, Ludovico P, Sansonetty F, Silva MT, Peinado JM, Corte-Real M (2005) Hyperosmotic stress induces metacaspase- and mitochondria-dependent apoptosis in Saccharomyces cerevisiae. Mol Microbiol 58:824–834Sole C, Nadal-Ribelles M, de Nadal E, Posas F (2015) A novel role for lncRNAs in cell cycle control during stress adaptation. Curr Genet 61:299–308Tamas MJ, Luyten K, Sutherland FC, Hernandez A, Albertyn J, Valadi H, Li H, Prior BA, Kilian SG, Ramos J, Gustafsson L, Thevelein JM, Hohmann S (1999) Fps1p controls the accumulation and release of the compatible solute glycerol in yeast osmoregulation. Mol Microbiol 31:1087–1104Teige M, Scheikl E, Reiser V, Ruis H, Ammerer G (2001) Rck2, a member of the calmodulin-protein kinase family, links protein synthesis to high osmolarity MAP kinase signaling in budding yeast. Proc Natl Acad Sci USA 98:5625–5630Timon-Gomez A, Proft M, Pascual-Ahuir A (2013) Differential regulation of mitochondrial pyruvate carrier genes modulates respiratory capacity and stress tolerance in yeast. PLoS One 8:e79405Vanacloig-Pedros E, Bets-Plasencia C, Pascual-Ahuir A, Proft M (2015) Coordinated gene regulation in the initial phase of salt stress adaptation. J Biol Chem 290:10163–10175Warringer J, Hult M, Regot S, Posas F, Sunnerhagen P (2010) The HOG pathway dictates the short-term translational response after hyperosmotic shock. Mol Biol Cell 21:3080–3092Wei CJ, Tanner RD, Malaney GW (1982) Effect of sodium chloride on bakers’ yeast growing in gelatin. Appl Environ Microbiol 43:757–763Westfall PJ, Patterson JC, Chen RE, Thorner J (2008) Stress resistance and signal fidelity independent of nuclear MAPK function. Proc Natl Acad Sci USA 105:12212–12217Ye T, Garcia-Salcedo R, Ramos J, Hohmann S (2006) Gis4, a new component of the ion homeostasis system in the yeast Saccharomyces cerevisiae. Eukaryot Cell 5:1611–1621Yoshida A, Wei D, Nomura W, Izawa S, Inoue Y (2012) Reduction of glucose uptake through inhibition of hexose transporters and enhancement of their endocytosis by methylglyoxal in Saccharomyces cerevisiae. J Biol Chem 287:701–71

    Molecular and physiological basis of Saccharomyces cerevisiae tolerance to adverse lignocellulose-based process conditions

    Get PDF
    Lignocellulose-based biorefineries have been gaining increasing attention to substitute current petroleum-based refineries. Biomass processing requires a pretreatment step to break lignocellulosic biomass recalcitrant structure, which results in the release of a broad range of microbial inhibitors, mainly weak acids, furans, and phenolic compounds. Saccharomyces cerevisiae is the most commonly used organism for ethanol production; however, it can be severely distressed by these lignocellulose-derived inhibitors, in addition to other challenging conditions, such as pentose sugar utilization and the high temperatures required for an efficient simultaneous saccharification and fermentation step. Therefore, a better understanding of the yeast response and adaptation towards the presence of these multiple stresses is of crucial importance to design strategies to improve yeast robustness and bioconversion capacity from lignocellulosic biomass. This review includes an overview of the main inhibitors derived from diverse raw material resultants from different biomass pretreatments, and describes the main mechanisms of yeast response to their presence, as well as to the presence of stresses imposed by xylose utilization and high-temperature conditions, with a special emphasis on the synergistic effect of multiple inhibitors/stressors. Furthermore, successful cases of tolerance improvement of S. cerevisiae are highlighted, in particular those associated with other process-related physiologically relevant conditions. Decoding the overall yeast response mechanisms will pave the way for the integrated development of sustainable yeast cell--based biorefineries.This study was supported by the Portuguese Foundation for Science and Technology (FCT) by the strategic funding of UID/BIO/04469/2013 unit, MIT Portugal Program (Ph.D. grant PD/BD/128247/ 2016 to Joana T. Cunha), Ph.D. grant SFRH/BD/130739/2017 to Carlos E. Costa, COMPETE 2020 (POCI-01-0145-FEDER-006684), BioTecNorte operation (NORTE-01-0145-FEDER-000004), YeasTempTation (ERA-IB-2-6/0001/2014), and MultiBiorefinery project (POCI-01-0145-FEDER-016403). Funding by the Institute for Bioengineering and Biosciences (IBB) from FCT (UID/BIO/04565/2013) and from Programa Operacional Regional de Lisboa 2020 (Project N. 007317) was also receiveinfo:eu-repo/semantics/publishedVersio

    DETERMINATION OF LATTICE PARAMETERS IN HCP COBALT BY USING X-RAY BOND'S METHOD

    No full text
    Measurements of lattice parameters a and c in hcp cobalt single crystals have been made in a temperature range between 4.2 K and room temperature by using the X-ray Bond's method. The results will be applicable to estimate various magnetic quantities such as the magnetocrystalline anisotropy energy
    • …
    corecore