DOCSLIB.ORG

Microrna-100 Suppresses Chronic Vascular Inflammation by Stimulation of Endothelial Autophagy

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Microrna-100 Suppresses Chronic Vascular Inflammation by Stimulation of Endothelial Autophagy MicroRNA-100 Suppresses Chronic Vascular Inflammation by Stimulation of Endothelial Autophagy Franziska Pankratz1, Catherine Hohnloser1, Xavier Bemtgen1, Caterina Jaenich1, Sheena Kreuzaler1, Imo Hoefer2, Gerard Pasterkamp2, Justin Mastroianni3, Robert Zeiser3, Christian Smolka1, Laura Schneider1, Julien Martin1, Maike Juschkat1, Thomas Helbing1, Martin Moser1, Christoph Bode1 1 Sebastian Grundmann 1Department of Cardiology and Angiology I, University Heart Center Freiburg, Germany; 2Experimental Cardiology Laboratory, University Medical Center Utrecht, The Netherlands, and;3Department of Hematology and Oncology, University Hospital Freiburg, Germany. Running title: MiR-100 Suppresses Chronic Vascular Inflammation Downloaded from http://circres.ahajournals.org/ by guest on January 9, 2018 Subject Terms: Atherosclerosis Basic Science Research Inflammation Gene Expression and Regulation Address correspondence to: Dr. Sebastian Grundmann Department of Cardiology and Angiology I Heart Center, University of Freiburg Hugstetter Str. 55 79106 Freiburg Germany Tel: +49 (0) 761 270 70460 Fax: +49 (0) 761 270 70450 [email protected] In November 2017, the average time from submission to first decision for all original research papers submitted to Circulation Research was 11.99 days. DOI: 10.1161/CIRCRESAHA.117.311428 1 ABSTRACT Rationale: The interaction of circulating cells within the vascular wall is a critical event in chronic inflammatory processes such as atherosclerosis, but the control of the vascular inflammatory state is still largely unclear. Objective: This study was undertaken to characterize the function of the endothelial-enriched microRNA miR-100 during vascular inflammation and atherogenesis. Methods and Results: Based on a transcriptome analysis of endothelial cells after miR-100 overexpression, we identified miR-100 as potent suppressor of endothelial adhesion molecule expression, resulting in attenuated leukocyte-endothelial interaction in vitro and in vivo as shown by flow cytometry and intravital imaging approach. Mechanistically, miR-100 directly repressed several components of mTORC1-signalling, including mTOR and raptor, which resulted in a stimulation of endothelial autophagy and attenuated NF-κB signaling in vitro and in vivo. In a LDLR-deficient atherosclerotic mouse model, pharmacologic inhibition of miR-100 resulted in enhanced plaque lesion formation and a higher macrophage content of the plaque, whereas a systemic miR-100 replacement Downloaded from therapy had protective effects and attenuated atherogenesis, resulting in a decrease of plaque area by 45%. Finally, analysis of miR-100 expression in more than 70 samples obtained during carotid endarterectomy revealed that local miR-100 expression was inversely correlated with inflammatory cell content in patients. http://circres.ahajournals.org/ Conclusion: In summary, we describe an anti-inflammatory function of miR-100 in the vascular response to injury and inflammation and identify an important novel modulator of mTOR signaling and autophagy in the vascular system. Our findings of miR-100 as a potential protective "anti-athero-miR" suggest that the therapeutic replacement of this miRNA could be a potential strategy for the treatment of chronic inflammatory diseases such as atherosclerosis in the future. Keywords: MicroRNA, atherosclerosis, inflammation, endothelium, arteriosclerosis, gene expression/regulation. by guest on January 9, 2018 DOI: 10.1161/CIRCRESAHA.117.311428 2 Nonstandard Abbreviations and Acronyms: Athero-Express Atherosclerotic plaque expression in relation to vascular events and patient characteristics CD Cluster of differentiation eNOS Endothelial NO synthase HDL High-density lipoprotein HEK Human embryonic kidney cells HFD High fat diet HMGCoA 3-hydroxy-3-methylglutaryl-coenzyme A HUVECs Human umbilical vein endothelial cells ICAM-1 Intracellular adhesion molecule 1 IKK IᴋB kinase IL Interleukin Keap-1 Kelch-like ECH associated protein 1 KLF2 Kruepple like factor 2 LDL Low-density lipoprotein Downloaded from LDLR Low-density lipoprotein receptor MCP-1 Monocyte chemoattractant protein 1 MIP-1 Macrophage inflammatory protein 1 miRNA microRNA mTOR Mammalian target of rapamycin http://circres.ahajournals.org/ mTORC1 mTOR complex 1 NFᴋB Nuclear factor 'kappa-light-chain-enhancer' of activated B-cells oxLDL Oxidized low-density lipoprotein sICAM-1 Soluble intracellular adhesion molecule 1 SMA Smooth muscle actin by guest on January 9, 2018 INTRODUCTION Inflammation is an important component of the host defense reaction against external pathogens and injury, but can also induce and maintain harmful conditions such as autoimmune diseases, atherosclerosis, in-stent restenosis or ischemia/reperfusion injury. The endothelial cell layer of blood vessels is a critical modulating structure in this process, as circulating immune cells need to attach to the endothelium and migrate into the vessel wall or the perivascular space to exert their function. In fact, the up-regulation of endothelial adhesion molecules due to alterations in fluid shear forces, hypertension or elevated LDL-cholesterol levels is one of the earliest steps in the initiation of atherosclerosis, which is now generally regarded as a chronic inflammatory disease1-3. Many attempts to modulate leukocyte-endothelial interaction to prevent or reduce excessive inflammatory reactions were made in the past. However, the basic regulatory principles of the endothelial inflammatory process remain unclear. It seems that the inhibition of individual components of the inflammatory cascade, e.g. by a single antibody against an adhesion molecule, may not be enough to achieve a sustained effect on vascular inflammation. In the past years, microRNAs (miRNAs) have been identified as important regulators of gene expression in a wide range of organisms and biological processes. MiRNAs are short (17-24 base pairs), non-coding, single stranded RNA-molecules that are transcribed as precursor molecules and processed to mature miRNAs. MiRNAs regulate the expression of their target genes by translational repression or mRNA degradation. MiRNAs play a key role in cellular proliferation, development and tissue remodeling. Currently, 2603 human and 1920 mouse miRNAs are annotated in the miRBASE 21.0 database, but even more human miRNAs are predicted and their identification and functional characterization is ongoing. DOI: 10.1161/CIRCRESAHA.117.311428 3 Several studies have implicated miRNAs as pivotal players in the regulation of different aspects of vascular biology. Our own group recently used miRNA-transcriptome profiling to screen for miRNAs involved in the regulation of adaptive neovascularization. We identified miR-100 as an endothelial enriched miRNA that attenuates blood vessel growth in response to ischemia following arterial occlusion in mice via repression of the pro-angiogenic and pro-arteriogenic signal transducer mammalian target of rapamycin (mTOR)4. In the present study we now aimed to explore the regulation and function of this miRNA in endothelial cells. Starting from a global transcriptome analysis of human umbilical vein endothelial cells (HUVECs) after miR-100 overexpression, we identified a potent regulatory role of miR-100 in the endothelial inflammatory response to injury. In addition, we demonstrate the modulation of miR-100 levels by pro- and anti-inflammatory stimuli and describe a novel mechanism by which miR-100 exerts strong anti-inflammatory properties in endothelial cells via the augmentation of endothelial autophagy. METHODS Downloaded from The detailed protocols of this study are available from the first author upon request. Transgenic mice are available from the commercial vendors. The microarray data created for this study have been made publicly available at the NCBI gene expression and hybridization array data repository (GEO, http://www.ncbi.nlm.nih.gov/geo/) and can be accessed under the accession number GSE 20668. http://circres.ahajournals.org/ A more detailed description of material and methods used in the manuscript can be found in the supplement. Cell culture experiments. Human umbilical vein endothelial cells (HUVECs) were isolated from donated umbilical cords, cultivated and used until passage five. HEK293A cells were cultured in Dulbecco`s Modified Eagle Medium (DMEM), Life technologies, Darmstadt, Germany, supplemented with 10 % FBS. For transfection protocols please refer to the online supplement. by guest on January 9, 2018 Autophagy detection kit. HUVECs were sowed in culture slides and miRNA expression levels were modulated. As positive control, cells were treated with 50 μM chloroquine for 24 h to artificially generate autophagosomes. Endothelial autophagy was analyzed by immunofluorescence staining against LC3B positive autophagosomes using the “LC3B antibody kit for autophagy”, Life technologies, Darmstadt, Germany. Following staining, the average number of LC3-II-positive autophagosomes per cell was counted in a randomly chosen imaging field (20 cells/ imaging field). The results of 20 cells were averaged. Animal experiments. C57/BL6J mice were purchased either from Charles River or from the local stock of the animal facility at University Hospital Freiburg, Germany. NF-ᴋB-RE-luc mice (BALB/c-Tg(Rela-luc)31Xen, #10499- M) were purchased from Taconic, Hudson, NY, USA and B6.129S7-Ldlrtm1Her/J (LDLR-/-) mice were obtained from the Jackson Laboratory. Mice were bred in a specific pathogen free animal facility of the University
Load more

Recommended publications
  • Microrna-33A Regulates Cholesterol Synthesis and Cholesterol Efflux
    Kostopoulou et al. Arthritis Research & Therapy (2015) 17:42 DOI 10.1186/s13075-015-0556-y RESEARCH ARTICLE Open Access MicroRNA-33a regulates cholesterol synthesis and cholesterol efflux-related genes in osteoarthritic chondrocytes Fotini Kostopoulou1,2, Konstantinos N Malizos2,3, Ioanna Papathanasiou1 and Aspasia Tsezou1,2,4* Abstract Introduction: Several studies have shown that osteoarthritis (OA) is strongly associated with metabolism-related disorders, highlighting OA as the fifth component of the metabolic syndrome (MetS). On the basis of our previous findings on dysregulation of cholesterol homeostasis in OA, we were prompted to investigate whether microRNA-33a (miR-33a), one of the master regulators of cholesterol and fatty acid metabolism, plays a key role in OA pathogenesis. Methods: Articular cartilage samples were obtained from 14 patients with primary OA undergoing total knee replacement surgery. Normal cartilage was obtained from nine individuals undergoing fracture repair surgery. Bioinformatics analysis was used to identify miR-33a target genes. miR-33a and sterol regulatory element-binding protein 2 (SREBP-2) expression levels were investigated using real-time PCR, and their expression was also assessed after treatment with transforming growth factor-β1(TGF-β1) in cultured chondrocytes.Aktphosphorylationafter treatment with both TGF-β1 and miR-33a inhibitor or TGF-β1 and miR-33a mimic was assessed by Western blot analysis. Furthermore, we evaluated the effect of miR-33a mimic and miR-33a inhibitor on Smad7,anegative regulator of TGF-β signaling, on cholesterol efflux-related genes, ATP-binding cassette transporter A1 (ABCA1), apolipoprotein A1 (ApoA1)andliverXreceptors(LXRα and LXRβ), as well as on matrix metalloproteinase-13 (MMP-13), using real-time PCR.
    [Show full text]
  • Ablation of Mir-144 Increases Vimentin Expression and Atherosclerotic Plaque Formation Quan He1, Fangfei Wang1, Takashi Honda1, Kenneth D
    www.nature.com/scientificreports OPEN Ablation of miR-144 increases vimentin expression and atherosclerotic plaque formation Quan He1, Fangfei Wang1, Takashi Honda1, Kenneth D. Greis2 & Andrew N. Redington1* It has been suggested that miR-144 is pro-atherosclerotic via efects on reverse cholesterol transportation targeting the ATP binding cassette protein. This study used proteomic analysis to identify additional cardiovascular targets of miR-144, and subsequently examined the role of a newly identifed regulator of atherosclerotic burden in miR-144 knockout mice receiving a high fat diet. To identify afected secretory proteins, miR-144 treated endothelial cell culture medium was subjected to proteomic analysis including two-dimensional gel separation, trypsin digestion, and nanospray liquid chromatography coupled to tandem mass spectrometry. We identifed 5 gel spots representing 19 proteins that changed consistently across the biological replicates. One of these spots, was identifed as vimentin. Atherosclerosis was induced in miR-144 knockout mice by high fat diet and vascular lesions were quantifed by Oil Red-O staining of the serial sectioned aortic root and from en-face views of the aortic tree. Unexpectedly, high fat diet induced extensive atherosclerosis in miR-144 knockout mice and was accompanied by severe fatty liver disease compared with wild type littermates. Vimentin levels were reduced by miR-144 and increased by antagomiR-144 in cultured cardiac endothelial cells. Compared with wild type, ablation of the miR-144/451 cluster increased plasma vimentin, while vimentin levels were decreased in control mice injected with synthetic miR-144. Furthermore, increased vimentin expression was prominent in the commissural regions of the aortic root which are highly susceptible to atherosclerotic plaque formation.
    [Show full text]
  • Cancer Stem Cells in Pancreatic Cancer
    Cancers 2010, 2, 1629-1641; doi:10.3390/cancers2031629 OPEN ACCESS cancers ISSN 2072-6694 www.mdpi.com/journal/cancers Review Cancer Stem Cells in Pancreatic Cancer Qi Bao †, Yue Zhao †, Andrea Renner, Hanno Niess, Hendrik Seeliger, Karl-Walter Jauch and Christiane J. Bruns * Department of Surgery, Ludwig Maximilian University of Munich, Klinikum Grosshadern, Marchioninistr. 15, D-81377, Munich, Germany; E-Mails: [email protected] (Q.B.); [email protected] (Y.Z.); [email protected] (A.R.); [email protected] (H.N.); [email protected] (H.S.); [email protected] (K.W.J.) † These authors contributed equally to this work. * Author to whom correspondence should be addressed; Tel.: +49-89-7095-3570; Fax: +49-89-7095-8894; E-Mail: [email protected]. Received: 2 July 2010; in revised form: 29 July 2010 / Accepted: 18 August 2010 / Published: 19 August 2010 Abstract: Pancreatic cancer is an aggressive malignant solid tumor well-known by early metastasis, local invasion, resistance to standard chemo- and radiotherapy and poor prognosis. Increasing evidence indicates that pancreatic cancer is initiated and propagated by cancer stem cells (CSCs). Here we review the current research results regarding CSCs in pancreatic cancer and discuss the different markers identifying pancreatic CSCs. This review will focus on metastasis, microRNA regulation and anti-CSC therapy in pancreatic cancer. Keywords: cancer stem cells; pancreatic cancer; signaling pathways; metastasis; CSC-related therapy; microRNAs 1. Introduction Stem cells are a subpopulation of cells that have the capability to differentiate into multiple cell types and maintain their self-renewal activity.
    [Show full text]
  • Development of Novel Therapeutic Agents by Inhibition of Oncogenic Micrornas
    International Journal of Molecular Sciences Review Development of Novel Therapeutic Agents by Inhibition of Oncogenic MicroRNAs Dinh-Duc Nguyen and Suhwan Chang * ID Department of Biomedical Sciences, University of Ulsan College of Medicine, Asan Medical Center, Seoul 05505, Korea; [email protected] * Correspondence: [email protected] Received: 21 November 2017; Accepted: 22 December 2017; Published: 27 December 2017 Abstract: MicroRNAs (miRs, miRNAs) are regulatory small noncoding RNAs, with their roles already confirmed to be important for post-transcriptional regulation of gene expression affecting cell physiology and disease development. Upregulation of a cancer-causing miRNA, known as oncogenic miRNA, has been found in many types of cancers and, therefore, represents a potential new class of targets for therapeutic inhibition. Several strategies have been developed in recent years to inhibit oncogenic miRNAs. Among them is a direct approach that targets mature oncogenic miRNA with an antisense sequence known as antimiR, which could be an oligonucleotide or miRNA sponge. In contrast, an indirect approach is to block the biogenesis of miRNA by genome editing using the CRISPR/Cas9 system or a small molecule inhibitor. The development of these inhibitors is straightforward but involves significant scientific and therapeutic challenges that need to be resolved. In this review, we summarize recent relevant studies on the development of miRNA inhibitors against cancer. Keywords: antimiR; antagomiR; miRNA-sponge; oncomiR; CRISPR/Cas9; cancer therapeutics 1. Introduction Cancer has been the leading cause of death and a major health problem worldwide for many years; basically, it results from out-of-control cell proliferation. Traditionally, several key proteins have been identified and found to affect signaling pathways regulating cell cycle progression, apoptosis, and gene transcription in various types of cancers [1,2].
    [Show full text]
  • The Positive Effect of Mir1 Antagomir on Ischemic Neurological Disorders Via Changing the Expression of Bcl-W and Bad Genes
    Basic and Clinical November, December 2020, Volume 11, Number 6 Research Paper: The Positive Effect of MiR1 Antagomir on Ischemic Neurological Disorders Via Changing the Expression of Bcl-w and Bad Genes Anis Talebi1 , Mehdi Rahnema2 , Mohammad Reza Bigdeli1* 1. Department of Biology, Faculty of Life Sciences and Biotechnology, Shahid Beheshti University, Tehran, Iran. 2. Department of Biology, Faculty of Engineering and Basic Sciences, Zanjan Branch, Islamic Azad University, Zanjan, Iran. Use your device to scan and read the article online Citation: Talebi, A., Rahnema, M., & Bigdeli, M. R. (2020). The Positive Effect of MiR1 Antagomir on Ischemic Neurological Disorders Via Changing the Expression of Bcl-w and Bad Genes. Basic and Clinical Neuroscience, 11(6), 811-820. http://dx.doi. org/10.32598/bcn.11.6.324.3 : http://dx.doi.org/10.32598/bcn.11.6.324.3 A B S T R A C T Introduction: MicroRNAs (miRNAs or miRs) are non-coding RNAs. Studies have shown that miRNAs are expressed aberrantly in stroke. The miR1 enhances ischemic damage, and Article info: a previous study has demonstrated that reduction of miR1 level has a neuroprotective effect Received: 26 Feb 2018 on the Middle Cerebral Artery Occlusion (MCAO). Since apoptosis is one of the important First Revision:10 Mar 2018 processes in neural protection, the possible effect of miR1 on this pathway has been tested in Accepted: 15 Oct 2019 this study. Post-ischemic administration of miR1 antagomir reduces infarct volume via bcl-w Available Online: 01 Nov 2020 and bad expression. Methods: Rats were divided into four experimental groups: sham, control, positive control, and antagomir treatment group.
    [Show full text]
  • Microrna21 Contributes to Myocardial Disease by Stimulating MAP Kinase
    Vol 456 | 18/25 December 2008 | doi:10.1038/nature07511 LETTERS MicroRNA-21 contributes to myocardial disease by stimulating MAP kinase signalling in fibroblasts Thomas Thum1,2*, Carina Gross3*, Jan Fiedler1,2, Thomas Fischer3, Stephan Kissler3, Markus Bussen5, Paolo Galuppo1, Steffen Just6, Wolfgang Rottbauer6, Stefan Frantz1, Mirco Castoldi7,8,Ju¨rgen Soutschek9, Victor Koteliansky10, Andreas Rosenwald4, M. Albert Basson11, Jonathan D. Licht12, John T. R. Pena13, Sara H. Rouhanifard13, Martina U. Muckenthaler7,8, Thomas Tuschl13, Gail R. Martin5, Johann Bauersachs1 & Stefan Engelhardt3,14 MicroRNAs comprise a broad class of small non-coding RNAs that fibroblasts; expression was highest in fibroblasts from the failing control expression of complementary target messenger RNAs1,2. heart, but was low in cardiomyocytes (Fig. 2c and data not shown). Dysregulation of microRNAs by several mechanisms has been 3–5 6–10 a Early stage Intermediate stage Late stage described in various disease states including cardiac disease . 2 ) Whereas previous studies of cardiac disease have focused on 2 microRNAs that are primarily expressed in cardiomyocytes, the 1 role of microRNAs expressed in other cell types of the heart is 0 unclear. Here we show that microRNA-21 (miR-21, also known as Mirn21) regulates the ERK–MAP kinase signalling pathway in –1 control mice (log control failure model versus failure cardiac fibroblasts, which has impacts on global cardiac structure miRNA level in heart –2 and function. miR-21 levels are increased selectively in fibroblasts *** of the failing heart, augmenting ERK–MAP kinase activity through b Non-failing inhibition of sprouty homologue 1 (Spry1). This mechanism reg- 6 Failing ulates fibroblast survival and growth factor secretion, apparently Non-failing Failing *** controlling the extent of interstitial fibrosis and cardiac hyper- Early miR-21 4 trophy.
    [Show full text]
  • Microrna Regulation of Human Pancreatic Cancer Stem Cells
    Review Article Page 1 of 7 microRNA regulation of human pancreatic cancer stem cells Yi-Fan Xu, Bethany N. Hannafon, Wei-Qun Ding Department of Pathology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, OK 73104, USA Contributions: (I) Conception and design: All authors; (II) Administrative support: None; (III) Provision of study materials or patients: None; (IV) Collection and assembly of data: None; (V) Data analysis and interpretation: None; (VI) Manuscript writing: All authors; (VII) Final approval of manuscript: All authors. Correspondence to: Dr. Wei-Qun Ding. Department of Pathology, University of Oklahoma Health Sciences Center, BRC 411A, 975 NE 10th Street, Oklahoma City, OK 73104, USA. Email: [email protected]. Abstract: microRNAs (miRNAs) are a group of small non-coding RNAs that function primarily in the post transcriptional regulation of gene expression in plants and animals. Deregulation of miRNA expression in cancer cells, including pancreatic cancer cells, is well documented, and the involvement of miRNAs in orchestrating tumor genesis and cancer progression has been recognized. This review focuses on recent reports demonstrating that miRNAs are involved in regulation of pancreatic cancer stem cells (CSCs). A number of miRNA species have been identified to be involved in regulating pancreatic CSCs, including miR-21, miR-34, miR-1246, miR-221, the miR-17-92 cluster, the miR-200 and let-7 families. Furthermore, the Notch-signaling pathway and epithelial-mesenchymal transition (EMT) process are associated with miRNA regulation of pancreatic CSCs. Given the significant contribution of CSCs to chemo-resistance and tumor progression, a better understanding of how miRNAs function in pancreatic CSCs could provide novel strategies for the development of therapeutics and diagnostics for this devastating disease.
    [Show full text]
  • Mir-122 in Hepatic Function and Liver Diseases
    Protein Cell 2012, 3(5): 364–371 DOI 10.1007/s13238-012-2036-3 Protein & Cell REVIEW MiR-122 in hepatic function and liver diseases Jun Hu, Yaxing Xu, Junli Hao, Saifeng Wang, Changfei Li, Songdong Meng CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences (CAS), Beijing 100101, China Correspondence: [email protected] Received February 5, 2012 Accepted February 22, 2012 ABSTRACT habditis elegans, especially the subsequent identification of another miRNA let-7 as a new posttranscriptional regulator of As the most abundant liver-specific microRNA, mi- gene expression more than a decade ago (Fire et al., 1998; croRNA-122 (miR-122) is involved in various physio- Reinhart et al., 2000), the small non-coding RNA known as logical processes in hepatic function as well as in liver miRNA has been extensively studied in plants, animals and pathology. There is now compelling evidence that miR- human beings. miRNAs are a large class of small non-coding 122, as a regulator of gene networks and pathways in and double-stranded RNA molecules of approximately 22 hepatocytes, plays a central role in diverse aspects of nucleotides in length. Full-length miRNAs are transcripted by hepatic function and in the progress of liver diseases. RNA polymerase II, which are called pri-miRNAs (hairpin This liver-enriched transcription factors-regulated precursors). These pri-miRNAs are processed by Drosha miRNA promotes differentiation of hepatocytes and within the nuclear compartment to produce pre-miRNAs
    [Show full text]
  • Therapeutic Evaluation of Micrornas by Molecular Imaging Thillai V
    Theranostics 2013, Vol. 3, Issue 12 964 Ivyspring International Publisher Theranostics 2013; 3(12):964-985. doi: 10.7150/thno.4928 Review Therapeutic Evaluation of microRNAs by Molecular Imaging Thillai V. Sekar1, Ramkumar Kunga Mohanram1, 2, Kira Foygel1, and Ramasamy Paulmurugan1 1. Molecular Imaging Program at Stanford, Bio-X Program, Department of Radiology, Stanford University School of Medicine, Stanford, California, USA. 2. Current address: SRM Research Institute, SRM University, Kattankulathur– 603 203, Tamilnadu, India Corresponding author: Ramasamy Paulmurugan, Ph.D. Department of Radiology, Stanford University School of Medicine, 1501, South California Avenue, #2217, Palo Alto, CA 94304. Phone: 650-725-6097; Fax: 650-721-6921. Email: [email protected] © Ivyspring International Publisher. This is an open-access article distributed under the terms of the Creative Commons License (http://creativecommons.org/ licenses/by-nc-nd/3.0/). Reproduction is permitted for personal, noncommercial use, provided that the article is in whole, unmodified, and properly cited. Received: 2013.07.26; Accepted: 2013.09.22; Published: 2013.12.06 Abstract MicroRNAs (miRNAs) function as regulatory molecules of gene expression with multifaceted activities that exhibit direct or indirect oncogenic properties, which promote cell proliferation, differentiation, and the development of different types of cancers. Because of their extensive functional involvement in many cellular processes, under both normal and pathological conditions such as various cancers, this class of molecules holds particular interest for cancer research. MiRNAs possess the ability to act as tumor suppressors or oncogenes by regulating the expression of different apoptotic proteins, kinases, oncogenes, and other molecular mechanisms that can cause the onset of tumor development.
    [Show full text]
  • Charakterisierung Der Funktionellen Bedeutung Der Mikrorna-34A Während Der Entwicklung Und Der Tumorgenese Mittels Eines Mausmodells
    Charakterisierung der funktionellen Bedeutung der mikroRNA-34a während der Entwicklung und der Tumorgenese mittels eines Mausmodells Inaugural-Dissertation zur Erlangung des Doktorgrades Dr. rer. nat. der Fakultät für Biologie an der Universität Duisburg-Essen vorgelegt von Theresa Thor aus Gelsenkirchen Juni 2012 Die der vorliegenden Arbeit zugrunde liegenden Experimente wurden im hämatologisch- onkologischen Labor der Kinderklinik III der Uniklinik Essen durchgeführt. 1. Gutachter: Prof. Dr. med. Johannes H. Schulte 2. Gutachter: PD. Dr. rer. nat. Wiebke Hansen 3. Gutachter: Prof. Dr. med. Olaf Witt Vorsitzender des Prüfungsausschusses: Prof. Dr. Michael Ehrmann Tag der mündlichen Prüfung: 16.11.2012 Für meine Eltern Inhaltsverzeichnis Inhaltsverzeichnis 1 Einleitung ........................................................................................................................... 1 1.1 Die Entdeckung der mikroRNAs ................................................................................. 1 1.2 Biogenese der mikroRNAs .......................................................................................... 2 1.3 Die Funktion von mikroRNAs ..................................................................................... 3 1.4 mikroRNAs während der Tumorgenese ...................................................................... 4 1.4.1 miRNAs als Onkogene ......................................................................................... 4 1.4.2 miRNAs als Tumorsuppressorgene .....................................................................
    [Show full text]
  • Microrna Therapeutics
    Gene Therapy (2011) 18, 1104–1110 & 2011 Macmillan Publishers Limited All rights reserved 0969-7128/11 www.nature.com/gt REVIEW MicroRNA therapeutics JA Broderick1 and PD Zamore2 MicroRNAs (miRNAs) provide new therapeutic targets for many diseases, while their myriad roles in development and cellular processes make them fascinating to study. We still do not fully understand the molecular mechanisms by which miRNAs regulate gene expression nor do we know the complete repertoire of mRNAs each miRNA regulates. However, recent progress in the development of effective strategies to block miRNAs suggests that anti-miRNA drugs may soon be used in the clinic. Gene Therapy (2011) 18, 1104–1110; doi:10.1038/gt.2011.50; published online 28 April 2011 Keywords: miRNA; antagomir; anti-miR; Argonaute; RNA silencing; miRNA inhibition INTRODUCTION within the pri-miRNA (Figure 1). Cleavage of the pri-miRNA by the MicroRNAs (miRNAs) are 21–23 nucleotide long RNAs that direct RNase III enzyme, Drosha, releases the pre-miRNA stem-loop, which Argonaute proteins to bind to and repress complementary mRNA bears the two nucleotide, 3¢ overhanging ends characteristic of RNase targets. The human genome contains more than 500 miRNAs, and III enzymes. The pre-miRNA is then exported to the cytoplasm, where each miRNA can repress hundreds of genes, regulating almost every its loop is removed by a second RNase III enzyme, Dicer, that cellular process.1,2 Individual miRNAs are often produced only in specifically recognizes the pre-miRNA structure, including its two specific cell types or developmental stages. nucleotide, 3¢ overhanging end. The resulting miRNA/miRNA* duplex Inappropriate miRNA expression has been linked to a variety of is then loaded into a member of the Argonaute family of proteins.
    [Show full text]
  • Systemic Delivery of Microrna As a Therapeutic Modality to Treat Cancer
    Systemic Delivery of miRNA as a Therapeutic Modality to Treat Cancer John P. Pozniak Submitted in partial fulfillment of the requirements for the degree of Master of Science in Cancer and Cell Biology Committee Chair: Daniel Starczynowski Committee Member: Chunying Du Committee Member: Kathryn Wikenheiser-Brokamp University of Cincinnati Cincinnati, OH April, 2013 Abstract MicroRNAs (miRNA) are small noncoding RNAs with an important role in the initiation and progression of human cancers by posttranscriptional regulation of tumors suppressors and oncogenes. Recent evidence showing miRNAs are aberrantly expressed in tumors underscores them as potential targets for therapeutic intervention. The rationale for developing miRNA-based cancer therapeutics is based on correcting miRNA expression by either antagonism or miRNA replacement in tumors that may provide therapeutic benefit. This article surveys the present knowledge of cancer-associated miRNAs and considers advantages and potential challenges of current delivery technologies employed to systemically deliver miRNAs to tumors by experimental and pre-clinical studies that have used these approaches. Table of Contents 1. Introduction 2. miRNA and Cancer Development 3. Circulating miRNAs as Biomarkers 4. miRNA Therapeutics 5. Efficacy of Systemic Delivery of miRNA With Available Delivery Systems 5.1 Adeno-Associated Virus 5.2 AntagomiRs 5.3 Atellocollagen 5.3 Lipid-Based 5.4 Exosomes 5.5 Non-lipid Nanoparticles 6. Concluding Remarks 7. References Table 1: Summary of Cancer-Associated miRNAs
    [Show full text]