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Yang J, DeVore AN, Fu DA, Spicer MM, Guo M, Thompson SG, Ahlers-Dannen KE, Polato F, Nussenzweig A, Fisher RA. Rapid and precise genotyping of transgene zygosity in mice using an allele-specific method. Life Sci Alliance 2023; 6:e202201729. [PMID: 37037594 PMCID: PMC10087101 DOI: 10.26508/lsa.202201729] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Revised: 03/22/2023] [Accepted: 03/23/2023] [Indexed: 04/12/2023] Open
Abstract
Precise determination of transgene zygosity is essential for use of transgenic mice in research. Because integration loci of transgenes are usually unknown due to their random insertion, assessment of transgene zygosity remains a challenge. Current zygosity genotyping methods (progeny testing, qPCR, and NGS-computational biology analysis) are time consuming, prone to error or technically challenging. Here, we developed a novel method to determine transgene zygosity requiring no knowledge of transgene insertion loci. This method applies allele-specific restriction enzyme digestion of PCR products (RE/PCR) to rapidly and reliably quantify transgene zygosity. We demonstrate the applicability of this method to three transgenic strains of mice (Atm TgC3001L, Nes-Cre, and Syn1-Cre) harboring a unique restriction enzyme site on either the transgene or its homologous sequence in the mouse genome. This method is as accurate as the gold standard of progeny testing but requires 2 d instead of a month or more. It is also exceedingly more accurate than the most commonly used approach of qPCR quantification. Our novel method represents a significant technical advance in determining transgene zygosities in mice.
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Affiliation(s)
- Jianqi Yang
- Departments of Neuroscience and Pharmacology, The University of Iowa, Iowa City, IA, USA
| | - Alison N DeVore
- Departments of Neuroscience and Pharmacology, The University of Iowa, Iowa City, IA, USA
| | - Daniel A Fu
- Departments of Neuroscience and Pharmacology, The University of Iowa, Iowa City, IA, USA
| | - Mackenzie M Spicer
- Departments of Neuroscience and Pharmacology, The University of Iowa, Iowa City, IA, USA
| | - Mengcheng Guo
- Departments of Neuroscience and Pharmacology, The University of Iowa, Iowa City, IA, USA
| | - Samantha G Thompson
- Departments of Neuroscience and Pharmacology, The University of Iowa, Iowa City, IA, USA
| | | | - Federica Polato
- Laboratory of Genome Integrity, National Institutes of Health, Centre for Cancer Research, Bethesda, MD, USA
| | - Andre Nussenzweig
- Laboratory of Genome Integrity, National Institutes of Health, Centre for Cancer Research, Bethesda, MD, USA
| | - Rory A Fisher
- Departments of Neuroscience and Pharmacology, The University of Iowa, Iowa City, IA, USA
- Roy J and Lucille A Carver College of Medicine, The University of Iowa, Iowa City, IA, USA
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Bullock J, Polato F, Abu-Asab M, Bernardo-Colón A, Aflaki E, Agbaga MP, Becerra SP. Degradation of Photoreceptor Outer Segments by the Retinal Pigment Epithelium Requires Pigment Epithelium-Derived Factor Receptor (PEDF-R). Invest Ophthalmol Vis Sci 2021; 62:30. [PMID: 33605986 PMCID: PMC7900850 DOI: 10.1167/iovs.62.2.30] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Accepted: 01/19/2021] [Indexed: 12/28/2022] Open
Abstract
Purpose To examine the contribution of pigment epithelium-derived factor receptor (PEDF-R) to the phagocytosis process. Previously, we identified PEDF-R, the protein encoded by the PNPLA2 gene, as a phospholipase A2 in the retinal pigment epithelium (RPE). During phagocytosis, RPE cells ingest abundant phospholipids and protein in the form of photoreceptor outer segment (POS) tips, which are then hydrolyzed. The role of PEDF-R in RPE phagocytosis is not known. Methods Mice in which PNPLA2 was conditionally knocked out (cKO) in the RPE were generated. Mouse RPE/choroid explants were cultured. Human ARPE-19 cells were transfected with siPNPLA2 silencing duplexes. POSs were isolated from bovine retinas. The phospholipase A2 inhibitor bromoenol lactone was used. Transmission electron microscopy, immunofluorescence, lipid labeling, pulse-chase experiments, western blots, and free fatty acid and β-hydroxybutyrate assays were performed. Results The RPE of the cKO mice accumulated lipids, as well as more abundant and larger rhodopsin particles, compared to littermate controls. Upon POS exposure, RPE explants from cKO mice released less β-hydroxybutyrate compared to controls. After POS ingestion during phagocytosis, rhodopsin degradation was stalled both in cells treated with bromoenol lactone and in PNPLA2-knocked-down cells relative to their corresponding controls. Phospholipase A2 inhibition lowered β-hydroxybutyrate release from phagocytic RPE cells. PNPLA2 knockdown also resulted in a decline in fatty acids and β-hydroxybutyrate release from phagocytic RPE cells. Conclusions PEDF-R downregulation delayed POS digestion during phagocytosis. The findings imply that the efficiency of RPE phagocytosis depends on PEDF-R, thus identifying a novel contribution of this protein to POS degradation in the RPE.
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Affiliation(s)
- Jeanee Bullock
- Section of Protein Structure and Function, Laboratory of Retinal Cell and Molecular Biology, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States
- Department of Biochemistry and Molecular & Cellular Biology, Georgetown University Medical Center, Washington DC, United States
| | - Federica Polato
- Section of Protein Structure and Function, Laboratory of Retinal Cell and Molecular Biology, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States
| | - Mones Abu-Asab
- Section of Histopathology, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States
| | - Alexandra Bernardo-Colón
- Section of Protein Structure and Function, Laboratory of Retinal Cell and Molecular Biology, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States
| | - Elma Aflaki
- Section of Protein Structure and Function, Laboratory of Retinal Cell and Molecular Biology, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States
| | - Martin-Paul Agbaga
- Departments of Cell Biology and Ophthalmology, Dean McGee Eye Institute, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States
| | - S. Patricia Becerra
- Section of Protein Structure and Function, Laboratory of Retinal Cell and Molecular Biology, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States
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Dixit S, Polato F, Samardzija M, Abu-Asab M, Grimm C, Crawford SE, Becerra SP. PEDF deficiency increases the susceptibility of rd10 mice to retinal degeneration. Exp Eye Res 2020; 198:108121. [PMID: 32721425 DOI: 10.1016/j.exer.2020.108121] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 06/09/2020] [Accepted: 06/15/2020] [Indexed: 12/29/2022]
Abstract
The SERPINF1 gene encodes pigment epithelium-derived factor (PEDF), a member of the serpin superfamily with neurotrophic and antiangiogenic properties in the retina. We hypothesized that absence of PEDF would lead to increased stress-associated retinal degeneration in Serpinf1 null mice. Accordingly, using a Serpinf1 null mouse model, we investigated the impact of PEDF absence on retinal morphology, and susceptibility to induced and inherited retinal degeneration. We studied the pattern of Serpinf1 expression in the mouse retina layers. PEDF protein was detected by western blotting. Transmission electron microscopy was performed on mouse retina. Serpinf1 null mice and wild type littermates were injected with NaIO3 (30 mg/kg body weight) intraperitonially. At post-injection day 1, 3, 4, 6 and 8 mice were euthanized, and eyes were enucleated. Serpinf1 null and rd10 double mutant mice were generated and their eyes enucleated at different time points from post-natal day 15 to post-natal day 28. Enucleated eyes were processed for hematoxylin and eosin staining and histopathological evaluations. We found that Serpinf1 was expressed in the retinal pigment epithelium, in the inner nuclear layer and in the ganglion cell layer, but undetectable in the outer nuclear layer of wild type mice. Plasma PEDF protein levels were undetectable in Serpinf1 null animals. RPE atrophy and retinal thinning were observed in NaIO3-treated wild type mice that progressed with time post-injection. NaIO3-treated Serpinf1 null mice showed comparatively better retinal morphology than wild type mice at day 4 post-injection. However, the absence of PEDF in Serpinf1 null x rd10 mice increased the susceptibility to retinal degeneration relative to that of rd10 mice. We concluded that histopathological evaluation of retinas lacking PEDF showed that removal of the Serpinf1 gene may activate PEDF-independent compensatory mechanisms to protect the retina against oxidative stress, while it increases the susceptibility to degenerate the retina in inherited retinal degeneration models.
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Affiliation(s)
- Shivani Dixit
- Section of Protein Structure and Function, LRCMB-NEI-NIH, Bethesda, MD, USA
| | - Federica Polato
- Section of Protein Structure and Function, LRCMB-NEI-NIH, Bethesda, MD, USA
| | - Marijana Samardzija
- Laboratory of Retinal Cell Biology, Department of Ophthalmology, University of Zurich, Zurich, Switzerland
| | | | - Christian Grimm
- Laboratory of Retinal Cell Biology, Department of Ophthalmology, University of Zurich, Zurich, Switzerland
| | - Susan E Crawford
- Department of Surgery, NorthShore University Health System Research Institute, Evanston, IL, USA
| | - S Patricia Becerra
- Section of Protein Structure and Function, LRCMB-NEI-NIH, Bethesda, MD, USA.
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Abstract
Pigment epithelium-derived factor (PEDF) is a natural protein of the retina with demonstrable neurotrophic properties, found in the interphotoreceptor matrix in intimate contact with photoreceptors. This review summarizes the effects of PEDF on photoreceptors in several animal models of retinal degeneration.
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Affiliation(s)
- Federica Polato
- Section of Protein Structure and Function, Laboratory of Retinal Cell and Molecular Biology, NEI, National Institutes of Health, NIH-NEI BG.6. Room 134. 6 Center Drive MSC 0608, 20892-0608, Bethesda, MD, USA.
| | - S Patricia Becerra
- Section of Protein Structure and Function, Laboratory of Retinal Cell and Molecular Biology, NEI, National Institutes of Health, NIH-NEI BG.6. Room 134. 6 Center Drive MSC 0608, 20892-0608, Bethesda, MD, USA.
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Kenealey J, Subramanian P, Comitato A, Bullock J, Keehan L, Polato F, Hoover D, Marigo V, Becerra SP. Small Retinoprotective Peptides Reveal a Receptor-binding Region on Pigment Epithelium-derived Factor. J Biol Chem 2015; 290:25241-53. [PMID: 26304116 DOI: 10.1074/jbc.m115.645846] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2015] [Indexed: 11/06/2022] Open
Abstract
The cytoprotective effects of pigment epithelium-derived factor (PEDF) require interactions between an as of a yet undefined region with a distinct ectodomain on the PEDF receptor (PEDF-R). Here we characterized the area in PEDF that interacts with PEDF-R to promote photoreceptor survival. Molecular docking studies suggested that the ligand binding site of PEDF-R interacts with the neurotrophic region of PEDF (44-mer, positions 78-121). Binding assays demonstrated that PEDF-R bound the 44-mer peptide. Moreover, peptide P1 from the PEDF-R ectodomain had affinity for the 44-mer and a shorter fragment within it, 17-mer (positions 98-114). Single residue substitutions to alanine along the 17-mer sequence were designed and tested for binding and biological activity. Altered 17-mer[R99A] did not bind to the P1 peptide, whereas 17-mer[H105A] had higher affinity than the unmodified 17-mer. Peptides 17-mer, 17-mer[H105A], and 44-mer exhibited cytoprotective effects in cultured retina R28 cells. Intravitreal injections of these peptides and PEDF in the rd1 mouse model of retinal degeneration decreased the numbers of dying photoreceptors, 17-mer[H105A] being most effective. The blocking peptide P1 hindered their protective effects both in retina cells and in vivo. Thus, in addition to demonstrating that the region composed of positions 98-114 of PEDF contains critical residues for PEDF-R interaction that mediates survival effects, the findings reveal distinct small PEDF fragments with neurotrophic effects on photoreceptors.
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Affiliation(s)
| | | | - Antonella Comitato
- the Department of Life Sciences, University of Modena and Reggio Emilia, 41125 Modena, Italy, and
| | - Jeanee Bullock
- From the National Eye Institute and the Department of Biochemistry and Molecular and Cellular Biology, Georgetown University, Washington, D. C. 20057
| | | | | | - David Hoover
- the Center for Information Technology, National Institutes of Health, Bethesda, Maryland 20892
| | - Valeria Marigo
- the Department of Life Sciences, University of Modena and Reggio Emilia, 41125 Modena, Italy, and
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Polato F, Bunting S, Wong N, Chen HT, Kozak M, Kruhlak M, Reczek C, Lee WH, Baer R, Ludwig T, Feigenbaum L, Jackson S, Nussenzweig A. CtIP-mediated resection is essential for viability and can operate independently of BRCA1. J Biophys Biochem Cytol 2014. [DOI: 10.1083/jcb.2054oia99] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Polato F, Callen E, Wong N, Faryabi R, Bunting S, Chen HT, Kozak M, Kruhlak MJ, Reczek CR, Lee WH, Ludwig T, Baer R, Feigenbaum L, Jackson S, Nussenzweig A. CtIP-mediated resection is essential for viability and can operate independently of BRCA1. ACTA ACUST UNITED AC 2014; 211:1027-36. [PMID: 24842372 PMCID: PMC4042650 DOI: 10.1084/jem.20131939] [Citation(s) in RCA: 95] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
In contrast to BRCA1, CtIP has indispensable roles in promoting resection and embryonic development. Homologous recombination (HR) is initiated by DNA end resection, a process in which stretches of single-strand DNA (ssDNA) are generated and used for homology search. Factors implicated in resection include nucleases MRE11, EXO1, and DNA2, which process DNA ends into 3′ ssDNA overhangs; helicases such as BLM, which unwind DNA; and other proteins such as BRCA1 and CtIP whose functions remain unclear. CDK-mediated phosphorylation of CtIP on T847 is required to promote resection, whereas CDK-dependent phosphorylation of CtIP-S327 is required for interaction with BRCA1. Here, we provide evidence that CtIP functions independently of BRCA1 in promoting DSB end resection. First, using mouse models expressing S327A or T847A mutant CtIP as a sole species, and B cells deficient in CtIP, we show that loss of the CtIP-BRCA1 interaction does not detectably affect resection, maintenance of genomic stability or viability, whereas T847 is essential for these functions. Second, although loss of 53BP1 rescues the embryonic lethality and HR defects in BRCA1-deficient mice, it does not restore viability or genome integrity in CtIP−/− mice. Third, the increased resection afforded by loss of 53BP1 and the rescue of BRCA1-deficiency depend on CtIP but not EXO1. Finally, the sensitivity of BRCA1-deficient cells to poly ADP ribose polymerase (PARP) inhibition is partially rescued by the phospho-mimicking mutant CtIP (CtIP-T847E). Thus, in contrast to BRCA1, CtIP has indispensable roles in promoting resection and embryonic development.
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Affiliation(s)
- Federica Polato
- Laboratory of Genome Integrity, Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Elsa Callen
- Laboratory of Genome Integrity, Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Nancy Wong
- Laboratory of Genome Integrity, Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Robert Faryabi
- Laboratory of Genome Integrity, Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Samuel Bunting
- Laboratory of Genome Integrity, Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Hua-Tang Chen
- Laboratory of Genome Integrity, Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Marina Kozak
- Laboratory of Genome Integrity, Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Michael J Kruhlak
- Laboratory of Genome Integrity, Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Colleen R Reczek
- Institute for Cancer Genetics, Department of Pathology and Cell Biology, Columbia University Medical Center, New York, NY 10032
| | - Wen-Hwa Lee
- Department of Biological Chemistry, School of Medicine, University of California, Irvine, CA 92697
| | - Thomas Ludwig
- Ohio State University Wexner Medical Center, Columbus, OH 43210
| | - Richard Baer
- Institute for Cancer Genetics, Department of Pathology and Cell Biology, Columbia University Medical Center, New York, NY 10032
| | - Lionel Feigenbaum
- Science Applications International Corporation-Frederick National Cancer Institute-Frederick Cancer Research and Development Center, Frederick, MD 21704
| | - Stephen Jackson
- The Wellcome Trust and Cancer Research UK Gurdon Institute and Department of Biochemistry, University of Cambridge, Cambridge CB2 1GA, England, UK The Wellcome Trust and Cancer Research UK Gurdon Institute and Department of Biochemistry, University of Cambridge, Cambridge CB2 1GA, England, UK The Wellcome Trust Sanger Institute, Hinxton CB10 1SA, England, UK
| | - André Nussenzweig
- Laboratory of Genome Integrity, Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
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Polato F, Rusconi P, Zangrossi S, Morelli F, Boeri M, Musi A, Marchini S, Castiglioni V, Scanziani E, Torri V, Broggini M. DRAGO (KIAA0247), a new DNA damage-responsive, p53-inducible gene that cooperates with p53 as oncosuppressor. [Corrected]. J Natl Cancer Inst 2014; 106:dju053. [PMID: 24652652 DOI: 10.1093/jnci/dju053] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND p53 influences genomic stability, apoptosis, autophagy, response to stress, and DNA damage. New p53-target genes could elucidate mechanisms through which p53 controls cell integrity and response to damage. METHODS DRAGO (drug-activated gene overexpressed, KIAA0247) was characterized by bioinformatics methods as well as by real-time polymerase chain reaction, chromatin immunoprecipitation and luciferase assays, time-lapse microscopy, and cell viability assays. Transgenic mice (94 p53(-/-) and 107 p53(+/-) mice on a C57BL/6J background) were used to assess DRAGO activity in vivo. Survival analyses were performed using Kaplan-Meier curves and the Mantel-Haenszel test. All statistical tests were two-sided. RESULTS We identified DRAGO as a new p53-responsive gene induced upon treatment with DNA-damaging agents. DRAGO is highly conserved, and its ectopic overexpression resulted in growth suppression and cell death. DRAGO(-/-) mice are viable without macroscopic alterations. However, in p53(-/-) or p53(+/-) mice, the deletion of both DRAGO alleles statistically significantly accelerated tumor development and shortened lifespan compared with p53(-/-) or p53(+/-) mice bearing wild-type DRAGO alleles (p53(-/-), DRAGO(-/-) mice: hazard ratio [HR] = 3.25, 95% confidence interval [CI] = 1.7 to 6.1, P < .001; p53(+/-), DRAGO(-/-) mice: HR = 2.35, 95% CI = 1.3 to 4.0, P < .001; both groups compared with DRAGO(+/+) counterparts). DRAGO mRNA levels were statistically significantly reduced in advanced-stage, compared with early-stage, ovarian tumors, but no mutations were found in several human tumors. We show that DRAGO expression is regulated both at transcriptional-through p53 (and p73) and methylation-dependent control-and post-transcriptional levels by miRNAs. CONCLUSIONS DRAGO represents a new p53-dependent gene highly regulated in human cells and whose expression cooperates with p53 in tumor suppressor functions.
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Affiliation(s)
- Federica Polato
- Affiliations of authors: Laboratory of Molecular Pharmacology (FP, PR, SZ, FM, MBo, AM, SM, MBr), and Laboratory of Methodology for Biomedical Research (VT), Department of Oncology, IRCCS-Istituto di Ricerche Farmacologiche Mario Negri, Milan, Italy; Dipartimento di Patologia Animale, Igiene e Sanità Pubblica Veterinaria, Università degli Studi di Milano, Milan, Italy (VC, ES); Mouse and Animal Pathology Laboratory, Fondazione Filarete, Milan, Italy (VC, ES); Present address: Laboratory of Genome Integrity, National Cancer Institute, National Institutes of Health, Bethesda, MD (FP)
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Mallampalli MP, Davies E, Wood D, Robertson H, Polato F, Carter CL. Role of environment and sex differences in the development of autoimmune diseases: a roundtable meeting report. J Womens Health (Larchmt) 2013; 22:578-86. [PMID: 23829184 DOI: 10.1089/jwh.2013.4462] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Autoimmune diseases (ADs) impose substantial health and financial burdens in the United States and in many parts of the world. Women are disproportionately affected by many of these disorders, which often contribute to lifelong disabilities. While the number of patients with some ADs appears to be rising, the complexities of conducting epidemiological studies prevent a thorough understanding of the prevalence and incidence of these various conditions. Research on environmental influences of these illnesses is limited, although they are generally hypothesized to result from the interaction of environmental agents in genetically susceptible individuals. Further, there is little known regarding the role of sex and gender in the environmentally influenced mechanisms leading to the development of AD. To address these issues, particularly the roles of environment and sex and gender in ADs and the factors that contribute to the rise in ADs, the Society for Women's Health Research convened an interdisciplinary roundtable of experts from academia, medicine, and government agencies to share their expertise, address knowledge gaps in research, and propose future research recommendations.
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Affiliation(s)
- Monica P Mallampalli
- Scientific Programs, Society for Women's Health Research, Washington, DC 20036, USA
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Caamano-Isorna F, Ramkumar MR, Doallo S, Corral M, Rodriguez-Holguin S, Cadaveira F, Nemtsov AV, Gilder D, Ehlers C, Gizer I, Yehuda R, Razvodovsky Y, Thorens G, Achab S, Peraro L, Lobello S, Rosa-Rizzotto E, Caroli D, Polato F, De Lazzari F, Grinakis E, Stathaki D, Sfakianaki E, Mouzas J, Salem B, Lesch OM, Mouzas I, Koulentaki M, Grinakis E, Liodaki N, Sfakianaki K, Stathaki D, Pikraki K, Aggouridaki R, Hovhannisyan K, Skagert E, Thornqvist K, Ohlsson M, Wikstrom MM, Tonnesen H, Anderson P, Gual A, Spak F, Bendtsen P, Keurhorst M, Segura L, Colom J, Reynolds J, Drummond C, Deluca P, van Steenkiste B, Mierzecki A, Kloda K, Wallace P, Newbury-Birch D, Kaner E, Laurant M, Wojnar M, Anderson P, Gual A, Spak F, Bendtsen P, Keurhorst M, Segura L, Colom J, Reynolds J, Drummond C, Deluca P, van Steenkiste B, Mierzecki A, Kloda K, Wallace P, Newbury-Birch D, Kaner E, Laurant M, Wojnar M, Anderson P, Gual A, Spak F, Bendtsen P, Keurhorst M, Segura L, Colom J, Reynolds J, Drummond C, Deluca P, van Steenkiste B, Mierzecki A, Kloda K, Wallace P, Newbury-Birch D, Kaner E, Laurant M, Wojnar M. EPIDEMIOLOGY. Alcohol Alcohol 2013. [DOI: 10.1093/alcalc/agt118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Moirand R, Gomez CD, Ngantcha M, Legarjean N, Travers D, Le Lan C, Guillery X, Perennes M, Kerdiles FJ, Brouard N, Lasbleiz M, Bellou A, Lobello S, Rosa-Rizzotto E, Peraro L, Caroli D, Polato F, Vendramin A, De Lazzari F, Barroso T, Jorge M, Vonkova H, Miovsky M, Gabrhelik R, Cablova L. O4 * FREE ORAL COMMUNICATIONS 4: ALCOHOL INTERVENTIONS IN DIFFERENT SETTINGS. Alcohol Alcohol 2013. [DOI: 10.1093/alcalc/agt096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Callen E, Di Virgilio M, Kruhlak MJ, Nieto-Soler M, Wong N, Chen HT, Faryabi RB, Polato F, Santos M, Starnes LM, Wesemann DR, Lee JE, Tubbs A, Sleckman BP, Daniel JA, Ge K, Alt FW, Fernandez-Capetillo O, Nussenzweig MC, Nussenzweig A. 53BP1 mediates productive and mutagenic DNA repair through distinct phosphoprotein interactions. Cell 2013; 153:1266-80. [PMID: 23727112 DOI: 10.1016/j.cell.2013.05.023] [Citation(s) in RCA: 258] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2013] [Revised: 04/09/2013] [Accepted: 05/10/2013] [Indexed: 01/13/2023]
Abstract
The DNA damage response (DDR) protein 53BP1 protects DNA ends from excessive resection in G1, and thereby favors repair by nonhomologous end-joining (NHEJ) as opposed to homologous recombination (HR). During S phase, BRCA1 antagonizes 53BP1 to promote HR. The pro-NHEJ and antirecombinase functions of 53BP1 are mediated in part by RIF1, the only known factor that requires 53BP1 phosphorylation for its recruitment to double-strand breaks (DSBs). Here, we show that a 53BP1 phosphomutant, 53BP18A, comprising alanine substitutions of the eight most N-terminal S/TQ phosphorylation sites, mimics 53BP1 deficiency by restoring genome stability in BRCA1-deficient cells yet behaves like wild-type 53BP1 with respect to immunoglobulin class switch recombination (CSR). 53BP18A recruits RIF1 but fails to recruit the DDR protein PTIP to DSBs, and disruption of PTIP phenocopies 53BP18A. We conclude that 53BP1 promotes productive CSR and suppresses mutagenic DNA repair through distinct phosphodependent interactions with RIF1 and PTIP.
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Affiliation(s)
- Elsa Callen
- Laboratory of Genome Integrity, National Cancer Institute, NIH, Bethesda, MD 20892, USA
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Rusconi P, Polato F, Musi A, Broggini M. Abstract 792: DRAGO (KIAA0247), a new p53-regulated antioncogene. Cancer Res 2013. [DOI: 10.1158/1538-7445.am2013-792] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
INTRODUCTION: The present work aims at functionally characterize DRAGO (DRug Activated Gene Overexpressed)/KIAA0247, an unknown, highly evolutionary-conserved gene. Data obtained in the lab showed that DRAGO is up-regulated by p53 in response to chemotherapeutic compound treatment in vitro and that its ectopic overexpression in cells growing in culture leads to cell death. DRAGO knockout mice are normal, fertile and do not develop tumors. At clinical level, lower DRAGO mRNA levels correlate to worse prognosis in colorectal and ovarian cancer patients. Preliminary evidences suggest a potential involvement of DRAGO in the control of immune response.
EXPERIMENTAL PROCEDURES: to verify if DRAGO may cooperate with p53 in counteracting tumor onset we crossed DRAGO and p53 knockout mice and evaluated the distribution of spontaneous tumors and the survival of double transgenic mice. DRAGO KO mice were generated by Cre recombinase-mediated-cassette-exchange approach. p53 KO mice were purchased from Jackson Lab. Mice were bred and PCR genotyped. Survival analysis were performed with GraphPad Prism 5 ®. Formalin fixed and paraffin embedded histological samples were hematoxylin/eosin stained and assessed by pathologists for diagnosis.
As regards macrophages isolation, PECs (Peritoneal Exudate Cells) were collected from DRAGO +/+ or -/- mice and M1 and M2 response were induced in vitro by LPS and IL4 treatment respectively. Gene expression was assessed with The TaqMan® Mouse Immune Array. Results were validated by FACS analysis.
RESULTS: DRAGO knockout negatively influenced survival: on a p53-/- background, deletion of either one or both DRAGO alleles progressively reduced survival (median survival: 166 and 139 days respectively) compared with DRAGO+/+ mice (190days). On a p53+/- background, DRAGO-/- and DRAGO+/- mice showed similar survival decrease (446 and 431 days respectively) compared with DRAGO+/+ mice (570 days). DRAGO genotype did not influence tumor incidence both in the p53-/- subpopulations (lymphomas 70%, sarcomas 30%), and in the p53+/- subpopulations (sarcomas 60%, lymphomas and carcinomas 20%).
PEC gene expression assessment displayed significant overexpression of CCR4 receptor on DRAGO-/- PECs, both in physiological conditions and upon M1 and M2 phenotype induction. FACS analysis confirmed that CCR4 expression is higher on DRAGO-/- PECs compared to DRAGO+/+ counterpart (43% vs 25% of positive cells).
CONCLUSIONS: crossing p53 and DRAGO knockout mice allowed us to demonstrate the oncosuppressive role of DRAGO in vivo and its cooperation with p53. Deletion of one or both DRAGO alleles determined a detrimental effect over survival both in p53-/- and in p53+/- mice. Also, DRAGO genotype did not affect tumor incidence on both p53 backgrounds. Preliminary data suggest that DRAGO might have a role in the macrophage functionality.
Citation Format: Paolo Rusconi, Federica Polato, Alberto Musi, Massimo Broggini. DRAGO (KIAA0247), a new p53-regulated antioncogene. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 792. doi:10.1158/1538-7445.AM2013-792
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Affiliation(s)
- Paolo Rusconi
- 1Mario Negri Institute for Pharmacological Research, Milan, Italy
| | | | - Alberto Musi
- 1Mario Negri Institute for Pharmacological Research, Milan, Italy
| | - Massimo Broggini
- 1Mario Negri Institute for Pharmacological Research, Milan, Italy
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Bothmer A, Rommel PC, Gazumyan A, Polato F, Reczek CR, Muellenbeck MF, Schaetzlein S, Edelmann W, Chen PL, Brosh RM, Casellas R, Ludwig T, Baer R, Nussenzweig A, Nussenzweig MC, Robbiani DF. Mechanism of DNA resection during intrachromosomal recombination and immunoglobulin class switching. J Biophys Biochem Cytol 2012. [DOI: 10.1083/jcb1997oia11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Bothmer A, Rommel PC, Gazumyan A, Polato F, Reczek CR, Muellenbeck MF, Schaetzlein S, Edelmann W, Chen PL, Brosh RM, Casellas R, Ludwig T, Baer R, Nussenzweig A, Nussenzweig MC, Robbiani DF. Mechanism of DNA resection during intrachromosomal recombination and immunoglobulin class switching. ACTA ACUST UNITED AC 2012; 210:115-23. [PMID: 23254285 PMCID: PMC3549709 DOI: 10.1084/jem.20121975] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
CtBP-interacting protein, exonuclease 1, and RecQ helicases contribute to the processing of DNA ends during double-strand break repairs in primary lymphocytes. DNA double-strand breaks (DSBs) are byproducts of normal cellular metabolism and obligate intermediates in antigen receptor diversification reactions. These lesions are potentially dangerous because they can lead to deletion of genetic material or chromosome translocation. The chromatin-binding protein 53BP1 and the histone variant H2AX are required for efficient class switch (CSR) and V(D)J recombination in part because they protect DNA ends from resection and thereby favor nonhomologous end joining (NHEJ). Here, we examine the mechanism of DNA end resection in primary B cells. We find that resection depends on both CtBP-interacting protein (CtIP, Rbbp8) and exonuclease 1 (Exo1). Inhibition of CtIP partially rescues the CSR defect in 53BP1- and H2AX-deficient lymphocytes, as does interference with the RecQ helicases Bloom (Blm) and Werner (Wrn). We conclude that CtIP, Exo1, and RecQ helicases contribute to the metabolism of DNA ends during DSB repair in B lymphocytes and that minimizing resection favors efficient CSR.
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Affiliation(s)
- Anne Bothmer
- Laboratory of Molecular Immunology, The Rockefeller University, New York, NY 10065, USA
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Rusconi P, Polato F, Musi A, Broggini M. 922 DRAGO, a P53/p73 Regulated Gene That Modulates Survival in Tumour Prone Mouse Model. Eur J Cancer 2012. [DOI: 10.1016/s0959-8049(12)71549-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Bunting SF, Callén E, Wong N, Chen HT, Polato F, Gunn A, Bothmer A, Feldhahn N, Fernandez-Capetillo O, Cao L, Xu X, Deng CX, Finkel T, Nussenzweig M, Stark JM, Nussenzweig A. 53BP1 inhibits homologous recombination in Brca1-deficient cells by blocking resection of DNA breaks. Cell 2010; 141:243-54. [PMID: 20362325 DOI: 10.1016/j.cell.2010.03.012] [Citation(s) in RCA: 1223] [Impact Index Per Article: 87.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2009] [Revised: 02/12/2010] [Accepted: 03/10/2010] [Indexed: 12/18/2022]
Abstract
Defective DNA repair by homologous recombination (HR) is thought to be a major contributor to tumorigenesis in individuals carrying Brca1 mutations. Here, we show that DNA breaks in Brca1-deficient cells are aberrantly joined into complex chromosome rearrangements by a process dependent on the nonhomologous end-joining (NHEJ) factors 53BP1 and DNA ligase 4. Loss of 53BP1 alleviates hypersensitivity of Brca1 mutant cells to PARP inhibition and restores error-free repair by HR. Mechanistically, 53BP1 deletion promotes ATM-dependent processing of broken DNA ends to produce recombinogenic single-stranded DNA competent for HR. In contrast, Lig4 deficiency does not rescue the HR defect in Brca1 mutant cells but prevents the joining of chromatid breaks into chromosome rearrangements. Our results illustrate that HR and NHEJ compete to process DNA breaks that arise during DNA replication and that shifting the balance between these pathways can be exploited to selectively protect or kill cells harboring Brca1 mutations.
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Affiliation(s)
- Samuel F Bunting
- Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
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Polato F, Codegoni A, Fruscio R, Perego P, Mangioni C, Saha S, Bardelli A, Broggini M. PRL-3 phosphatase is implicated in ovarian cancer growth. Clin Cancer Res 2006; 11:6835-9. [PMID: 16203771 DOI: 10.1158/1078-0432.ccr-04-2357] [Citation(s) in RCA: 121] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE The PRL-3 phosphatase has been found expressed at higher levels in metastasis than in primary tumors of patients with colorectal cancer. In the present study, we evaluated the expression of PRL-3 in ovarian cancer tissue and its role in ovarian cancer cell growth. EXPERIMENTAL DESIGN PRL-3 phosphatase expression was evaluated in 84 ovarian tumor samples. PRL-3 expression has been knocked down using specific small interfering RNAs to determine its role in ovarian cancer cell growth in vitro. RESULTS In ovarian cancers, PRL-3 expression correlates with disease progression, being higher in advanced (stage III) than in early (stage I) tumors. In situ measurements of PRL-3 expression showed that it was confined to the epithelial neoplastic cells. The molecular mechanism underlying PRL-3 overexpression in ovarian cancers is independent from amplification of the corresponding genomic locus. Ovarian cancer cells growing in culture have high levels of expression of this phosphatase. PRL-3-specific knockdown using small interfering RNA severely impaired the growth of cells without affecting the expression of the closely related homologue PRL-1. Intriguingly, the growth of human colon carcinoma cells expressing lower levels of the PRL-3 was not affected by the PRL-3 knockdown. CONCLUSIONS Altogether, these results show that PRL-3 expression is associated with ovarian cancer progression and point to a key role for this phosphatase in the control of ovarian cancer cells growth. This strongly suggests that PRL-3 should be considered as a target for the discovery of new anticancer agents to be tested against this malignancy.
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Affiliation(s)
- Federica Polato
- Laboratory of Molecular Pharmacology, Department of Oncology, Istituto di Ricerche Farmacologiche Mario Negri, Milan, Italy
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Marabese M, Marchini S, Sabatino MA, Polato F, Vikhanskaya F, Marrazzo E, Riccardi E, Scanziani E, Broggini M. Effects of inducible overexpression of DNp73alpha on cancer cell growth and response to treatment in vitro and in vivo. Cell Death Differ 2005; 12:805-14. [PMID: 15877106 DOI: 10.1038/sj.cdd.4401622] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
The p73 gene has a complex regulation, which leads to the expression of different isoforms, often with opposite biological effects. We have generated in the human colocarcinoma cell line HCT116, expressing a wild-type p53, an inducible DNp73alpha expressing system. Two clones (HCT116/DN3 and HCT116/DN14), upon doxycycline addition, show a strong expression of DNp73alpha. In vitro the two DNp73alpha overexpressing clones grow at similar rate of the control transfected clone (HCT116/8a) and similarly respond to DNA damage. When injected in mice, HCT116/DN3, HCT116/DN14, and HCT116/8a cells grew similarly in the absence or presence of tetracycline. In HCT116/DN3 and HCT116/DN14 tumors, tetracycline induced a strong expression of DNp73alpha both as mRNA and protein. These results indicate that in this system the overexpression of the DNp73alpha does not induce a more aggressive phenotype and does not seem to be associated with a reduced response of the cells to treatment with anticancer agents.
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Affiliation(s)
- M Marabese
- Laboratory of Molecular Pharmacology, Istituto di Ricerche Farmacologiche Mario Negri, Via Eritrea 62, 20157 Milan, Italy.
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Finco C, Sarzo G, Parise P, Savastano S, De Lazzari F, Polato F, Merigliano S. Laparoscopic treatment of post-hysterectomy colovaginal fistula in diverticular disease. Case report. MINERVA CHIR 2004; 59:301-5. [PMID: 15252398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/30/2023]
Abstract
Colonic diverticular disease is a benign condition typical of the Western world, but it is not rare for even the 1st episode of diverticulitis to carry potentially fatal complications. The evolution of a peridiverticular process generally poses problems for medical treatment and exposes patients to repeated episodes of diverticulitis, making surgical treatment necessary in approximately 30% of symptomatic patients. One of the most worrying complications of diverticulosis is internal fistula. The most common types of fistula are colovesical and colovaginal, against which the uterus can act as an important protective factor. The symptoms and the clinical and instrumental management of patients with diverticular fistulas are much the same as for patients with episodes of acute diverticulitis. Staging of the disease (according to Hinchey) should be done promptly so that the necessary action can be taken prior to surgery, implementing total parenteral nutrition (TPN), nasogastric aspiration and broad-spectrum antibiotic treatment. The best surgical approach to adopt in patients with diverticulitis complicated by fistula is still not entirely clear, though the 3-step strategy is currently tending to be abandoned due to its high morbidity and mortality rates. There is a widespread conviction, however, that the 2-step strategy (Hartmann, or resection with protective stomy) and the 1-step alternative should be reserved, respectively, for patients in Hinchey stages 3, 4 and 1, 2 with a situation of attenuated local inflammation. The 1-step approach seems to be safe and effective. This report describes a case of colovaginal fistula in a patient with colonic diverticulosis who had recently undergone hysterectomy, but who, unlike such cases in the past, was treated in a single step using a laparoscopic technique.
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Affiliation(s)
- C Finco
- Department of Medical and Surgical Sciences, IV General Surgical Clinic, University of Padua, Padua, Italy
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Polato F, Broggini M. Microsatellite instability and genetic alterations in ovarian cancer. Minerva Ginecol 2003; 55:129-38. [PMID: 12711999] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/02/2023]
Abstract
Inactivation of the mismatch repair system (MMR) leads to the accumulation of mutations, particularly in highly repeated sequences (microsatellite). The resulting microsatellite instability can profoundly affect the cellular behaviour, since many genes playing important roles in the mechanisms of signal transduction, apoptosis, DNA repair and cell cycle control can be altered in tumors presenting microsatellite instability. Germline mutations in MMR genes are associated with hereditary non polyposis colon cancer. Microsatellite instability and the associated frameshift mutations in genes have been well described in sporadic colon, gastric and endometrium tumors. In this review we collected the data available on the impact of microsatellite instability in ovarian cancer and the possible consequences of this instability to the presence of mutations in genes containing in their coding regions repeated nucleotides and to the response of these tumors to chemotherapy.
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Affiliation(s)
- F Polato
- Laboratory of Molecular Pharmacology, Institute for Pharmacological Research, Mario Negri, Milan, Italy
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Abstract
The ability of the TRAIL ligand to induce cell killing in three ovarian cancer cell lines was investigated using a glutathione-S-transferase (GST)-TRAIL fusion protein. One of the three lines was sensitive to TRAIL, which induced cell killing in a range of concentrations similar to those necessary to kill the TRAIL-sensitive leukaemic cell line Jurkat. The relative mRNA expression of the four TRAIL receptors did not explain the different sensitivities of the three ovarian cancer cell lines to TRAIL treatment. The TRAIL-sensitive IGROV-1 cell line expressed slightly lower levels of the anti-apoptotic protein FLIP than the two TRAIL-insensitive cell lines (A2780 and SKOV-3). Nevertheless, although TRAIL did not significantly reduce cell growth in the A2780 and SKOV-3 cells it did enhance the activity of paclitaxel and cisplatin (DDP), the two most widely used drugs for the treatment of ovarian cancer, increasing their ability to induce apoptosis. The use of TRAIL in combination with classical anticancer agents might thus boost the apoptotic response, improving the activity of DDP and paclitaxel in ovarian cancer.
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Affiliation(s)
- S Vignati
- Laboratory of Molecular Pharmacology, Department of Oncology, Istituto di Ricerche Farmacologiche Mario Negri, Via Eritrea 62, 20157 Milan, Italy
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Simonato B, De Lazzari F, Pasini G, Polato F, Giannattasio M, Gemignani C, Peruffo AD, Santucci B, Plebani M, Curioni A. IgE binding to soluble and insoluble wheat flour proteins in atopic and non-atopic patients suffering from gastrointestinal symptoms after wheat ingestion. Clin Exp Allergy 2001; 31:1771-8. [PMID: 11696054 DOI: 10.1046/j.1365-2222.2001.01200.x] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
BACKGROUND The involvement of IgE-mediated hypersensitivity reactions in the genesis of gastrointestinal symptoms after ingestion of foods containing wheat has been rarely reported. OBJECTIVE To detect IgE specifically binding to wheat proteins in the sera of atopic and non-atopic patients suffering from gastrointestinal symptoms after ingestion of wheat and to evaluate the reliability of skin prick test and CAP in the diagnosis of food allergy to wheat. METHODS The sera of patients (10 atopic and 10 non-atopic) previously diagnosed as suffering from irritable bowel syndrome and complaining of symptoms after wheat ingestion were analysed by immunoblotting for IgE binding to water/salt-soluble and insoluble wheat flour proteins. RESULTS All the atopic patients and only one of the non-atopic patients were positive to wheat CAP. For the patients tested, skin prick test was positive for all the atopic patients and for only one of the non-atopic patients. However, immunoblotting experiments showed the presence of specific IgE to wheat proteins in all the patients. Ten out of 11 of the wheat CAP-positive patients had IgE binding to a soluble 16-kDa band, but the same band was recognized, in a slighter way, by only two out of nine of the wheat CAP-negative patients. Moreover, although almost all of the patients were negative in CAP testing with gluten, 19 out of 20 recognized protein bands belonging to the prolamin fraction. CONCLUSIONS For the atopic patients the positivity to skin prick test and CAP to wheat was in accordance with the immunoblotting results and a food allergy to wheat could be diagnosed. In these patients a major allergen was a 16-kDa band corresponding to members of the cereal alpha-amylase/trypsin inhibitors protein family, the major allergens involved in baker's asthma. In the non-atopic patients the positive immunoblotting results contrasted with the responses of the allergologic tests, indicating that the allergenic wheat protein preparations currently used are of limited value in detecting specific IgE to wheat and that the fraction of irritable bowel syndrome (IBS) patients with food allergy may be larger than believed.
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Affiliation(s)
- B Simonato
- Dipartimento di Biotecnologie Agrarie, Università di Padova, Padova, Italy
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D'Orazio L, Mancarella C, Martuscelli E, Polato F. Polypropylene/ethylene-co-propylene blends: influence of molecular structure and composition of EPR on melt rheology, morphology and impact properties of injection-moulded samples. POLYMER 1991. [DOI: 10.1016/0032-3861(91)90220-d] [Citation(s) in RCA: 91] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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