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Magistri M, Velmeshev D, Makhmutova M, Patel P, Sartor GC, Volmar CH, Wahlestedt C, Faghihi MA. The BET-Bromodomain Inhibitor JQ1 Reduces Inflammation and Tau Phosphorylation at Ser396 in the Brain of the 3xTg Model of Alzheimer's Disease. Curr Alzheimer Res 2017; 13:985-95. [PMID: 27117003 PMCID: PMC5026248 DOI: 10.2174/1567205013666160427101832] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Accepted: 04/25/2016] [Indexed: 12/17/2022]
Abstract
BACKGROUND Alzheimer's disease (AD) is a progressive neurodegenerative disease characterized by welldefined neuropathological brain changes including amyloid plaques, neurofibrillary tangles and the presence of chronic neuroinflammation. OBJECTIVE The brain penetrant BET bromodomain inhibitor JQ1 has been shown to regulate inflammation responses in vitro and in vivo, but its therapeutic potential in AD is currently unknown. METHOD Three-month-old 3xTg mice were injected once a day with JQ1 (50 mg/kg) or vehicle for 15 weeks. At the end of the treatment learning and memory was assessed using the modified Barnes maze and the Y maze behavioral tests. Tissue from the brain and other organs was collected for molecular evaluation of neuroinflammation tau pathology and amyloid β. RESULTS JQ1 treatment reduced splenomegaly and neuroinflammation in the brain of treated mice where we observed a reduction in the expression of the pro-inflammatory modulators Il-1b, Il-6, Tnfa, Ccl2, Nos2 and Ptgs2. Additionally, JQ1-treated mice showed a reduction of tau phosphorylation at Ser396 in the hippocampus and frontal cortex while total levels of tau remained unaffected. On the other hand, JQ1 did not ameliorate learning and memory deficits in 7-month-old 3xTg mice. CONCLUSION Taken together, our data suggest that BET bromodomain inhibitors hold the promise to be used for the treatment of neurological disorders characterized by neuroinflammation.
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Affiliation(s)
| | | | | | | | | | | | | | - Mohammad Ali Faghihi
- Center for Therapeutic Innovation & Department of Psychiatry and Behavioral Sciences, University of Miami Miller School of Medicine, 1501 NW 10th Ave, BRB 508, Miami, FL 33136, USA.
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2
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Pisignano G, Napoli S, Magistri M, Mapelli SN, Pastori C, Di Marco S, Civenni G, Albino D, Enriquez C, Allegrini S, Mitra A, D'Ambrosio G, Mello-Grand M, Chiorino G, Garcia-Escudero R, Varani G, Carbone GM, Catapano CV. A promoter-proximal transcript targeted by genetic polymorphism controls E-cadherin silencing in human cancers. Nat Commun 2017; 8:15622. [PMID: 28555645 PMCID: PMC5459991 DOI: 10.1038/ncomms15622] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2016] [Accepted: 04/12/2017] [Indexed: 02/06/2023] Open
Abstract
Long noncoding RNAs are emerging players in the epigenetic machinery with key roles in development and diseases. Here we uncover a complex network comprising a promoter-associated noncoding RNA (paRNA), microRNA and epigenetic regulators that controls transcription of the tumour suppressor E-cadherin in epithelial cancers. E-cadherin silencing relies on the formation of a complex between the paRNA and microRNA-guided Argonaute 1 that, together, recruit SUV39H1 and induce repressive chromatin modifications in the gene promoter. A single nucleotide polymorphism (rs16260) linked to increased cancer risk alters the secondary structure of the paRNA, with the risk allele facilitating the assembly of the microRNA-guided Argonaute 1 complex and gene silencing. Collectively, these data demonstrate the role of a paRNA in E-cadherin regulation and the impact of a noncoding genetic variant on its function. Deregulation of paRNA-based epigenetic networks may contribute to cancer and other diseases making them promising targets for drug discovery.
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Affiliation(s)
- Giuseppina Pisignano
- Tumor Biology and Experimental Therapeutics Program, Institute of Oncology Research (IOR), and Oncology Institute of Southern Switzerland (IOSI), Bellinzona 6500, Switzerland
| | - Sara Napoli
- Tumor Biology and Experimental Therapeutics Program, Institute of Oncology Research (IOR), and Oncology Institute of Southern Switzerland (IOSI), Bellinzona 6500, Switzerland
| | - Marco Magistri
- Tumor Biology and Experimental Therapeutics Program, Institute of Oncology Research (IOR), and Oncology Institute of Southern Switzerland (IOSI), Bellinzona 6500, Switzerland
| | - Sarah N Mapelli
- Tumor Biology and Experimental Therapeutics Program, Institute of Oncology Research (IOR), and Oncology Institute of Southern Switzerland (IOSI), Bellinzona 6500, Switzerland
| | - Chiara Pastori
- Tumor Biology and Experimental Therapeutics Program, Institute of Oncology Research (IOR), and Oncology Institute of Southern Switzerland (IOSI), Bellinzona 6500, Switzerland
| | - Stefano Di Marco
- Tumor Biology and Experimental Therapeutics Program, Institute of Oncology Research (IOR), and Oncology Institute of Southern Switzerland (IOSI), Bellinzona 6500, Switzerland
| | - Gianluca Civenni
- Tumor Biology and Experimental Therapeutics Program, Institute of Oncology Research (IOR), and Oncology Institute of Southern Switzerland (IOSI), Bellinzona 6500, Switzerland
| | - Domenico Albino
- Tumor Biology and Experimental Therapeutics Program, Institute of Oncology Research (IOR), and Oncology Institute of Southern Switzerland (IOSI), Bellinzona 6500, Switzerland
| | - Claudia Enriquez
- Tumor Biology and Experimental Therapeutics Program, Institute of Oncology Research (IOR), and Oncology Institute of Southern Switzerland (IOSI), Bellinzona 6500, Switzerland
| | - Sara Allegrini
- Tumor Biology and Experimental Therapeutics Program, Institute of Oncology Research (IOR), and Oncology Institute of Southern Switzerland (IOSI), Bellinzona 6500, Switzerland
| | - Abhishek Mitra
- Tumor Biology and Experimental Therapeutics Program, Institute of Oncology Research (IOR), and Oncology Institute of Southern Switzerland (IOSI), Bellinzona 6500, Switzerland
| | | | | | - Giovanna Chiorino
- Laboratory of Cancer Genomics, Fondo Edo Tempia, Biella 13900, Italy
| | - Ramon Garcia-Escudero
- Tumor Biology and Experimental Therapeutics Program, Institute of Oncology Research (IOR), and Oncology Institute of Southern Switzerland (IOSI), Bellinzona 6500, Switzerland.,Molecular Oncology Unit, CIEMAT and Centro de Investigación Biomédica en Red de Cáncer (CIBERONC), Madrid 28040, Spain
| | - Gabriele Varani
- Department of Chemistry, University of Washington, Seattle, Washington 98195-1700, USA
| | - Giuseppina M Carbone
- Tumor Biology and Experimental Therapeutics Program, Institute of Oncology Research (IOR), and Oncology Institute of Southern Switzerland (IOSI), Bellinzona 6500, Switzerland
| | - Carlo V Catapano
- Tumor Biology and Experimental Therapeutics Program, Institute of Oncology Research (IOR), and Oncology Institute of Southern Switzerland (IOSI), Bellinzona 6500, Switzerland.,Department of Oncology, Faculty of Biology and Medicine, University of Lausanne, Lausanne 1066, Switzerland
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3
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Abstract
There are many classes of noncoding RNAs (ncRNAs), with wide-ranging functionalities (e.g., RNA editing, mediation of mRNA splicing, ribosomal function). MicroRNAs (miRNAs) and long ncRNAs (lncRNAs) are implicated in a wide variety of cellular processes, including the regulation of gene expression. Incorrect expression or mutation of lncRNAs has been reported to be associated with several disease conditions, such a malignant transformation in humans. Importantly, pivotal players in tumorigenesis and cancer progression, such as c-Myc, may be regulated by lncRNA at promoter level. The function of lncRNA can be reduced with antisense oligonucleotides that sequester or degrade mature lncRNAs. In alternative, lncRNA transcription can be blocked by small interference RNA (RNAi), which had acquired, recently, broad interested in clinical applications. In vivo-jetPEI™ is a linear polyethylenimine mediating nucleic acid (DNA, shRNA, siRNA, oligonucelotides) delivery with high efficiency. Different in vivo delivery routes have been validated: intravenous (IV), intraperitoneal (IP), intratumoral, subcutaneous, topical, and intrathecal. High levels of nucleic acid delivery are achieved into a broad range of tissues, such as lung, salivary glands, heart, spleen, liver, and prostate upon systemic administration. In addition, in vivo-jetPEI™ is also an efficient carrier for local gene and siRNA delivery such as intratumoral or topical application on the skin. After systemic injection, siRNA can be detected and the levels can be validated in target tissues by qRT-PCR. Targeting promoter-associated lncRNAs with siRNAs (small interfering RNAs) in vivo is becoming an exciting breakthrough for the treatment of human disease.
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Affiliation(s)
- Gianluca Civenni
- Laboratory of Experimental Therapeutics, IOR, Institute of Oncology Research, Via Vela 6, Bellinzona, 6500, Switzerland.
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Magistri M, Velmeshev D, Makhmutova M, Faghihi MA. Transcriptomics Profiling of Alzheimer's Disease Reveal Neurovascular Defects, Altered Amyloid-β Homeostasis, and Deregulated Expression of Long Noncoding RNAs. J Alzheimers Dis 2016; 48:647-65. [PMID: 26402107 PMCID: PMC4698155 DOI: 10.3233/jad-150398] [Citation(s) in RCA: 135] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The underlying genetic variations of late-onset Alzheimer's disease (LOAD) cases remain largely unknown. A combination of genetic variations with variable penetrance and lifetime epigenetic factors may converge on transcriptomic alterations that drive LOAD pathological process. Transcriptome profiling using deep sequencing technology offers insight into common altered pathways regardless of underpinning genetic or epigenetic factors and thus represents an ideal tool to investigate molecular mechanisms related to the pathophysiology of LOAD. We performed directional RNA sequencing on high quality RNA samples extracted from hippocampi of LOAD and age-matched controls. We further validated our data using qRT-PCR on a larger set of postmortem brain tissues, confirming downregulation of the gene encoding substance P (TAC1) and upregulation of the gene encoding the plasminogen activator inhibitor-1 (SERPINE1). Pathway analysis indicates dysregulation in neural communication, cerebral vasculature, and amyloid-β clearance. Beside protein coding genes, we identified several annotated and non-annotated long noncoding RNAs that are differentially expressed in LOAD brain tissues, three of them are activity-dependent regulated and one is induced by Aβ(1-42) exposure of human neural cells. Our data provide a comprehensive list of transcriptomics alterations in LOAD hippocampi and warrant holistic approach including both coding and non-coding RNAs in functional studies aimed to understand the pathophysiology of LOAD.
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Affiliation(s)
| | | | | | - Mohammad Ali Faghihi
- Correspondence to: Dr. Mohammad A. Faghihi, Center for Therapeutic Innovation & Department of Psychiatry and Behavioral Sciences, University of Miami Miller School of Medicine, 1501 NW 10th Ave, BRB 508, Miami, FL 33136, USA.
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5
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The long non-coding RNA FMR4 promotes proliferation of human neural precursor cells and epigenetic regulation of gene expression in trans. Mol Cell Neurosci 2016; 74:49-57. [PMID: 27001315 DOI: 10.1016/j.mcn.2016.03.008] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2015] [Revised: 03/04/2016] [Accepted: 03/17/2016] [Indexed: 01/21/2023] Open
Abstract
Triplet repeat expansions in the Fragile X mental retardation 1 (FMR1) gene cause either intellectual disability and autism, or adult-onset neurodegeneration, with poorly understood variability in presentation. Previous studies have identified several long noncoding RNAs (lncRNAs) at the FMR1 locus, including FMR4. Similarly to FMR1, FMR4 is silenced by large-repeat expansions that result in enrichment of DNA and histone methylation within the shared promoter and repeat sequence, suggesting a possible role for this noncoding RNA in the pathophysiology of Fragile X. We therefore assessed the functional role of FMR4 to gain further insight into the molecular processes in Fragile X-associated disorders. Previous work showed that FMR4 does not exhibit cis-regulation of FMR1. Here, we found that FMR4 is a chromatin-associated transcript and, using genome-wide chromatin immunoprecipitation experiments, showed that FMR4 alters the chromatin state and the expression of several hundred genes in trans. Among the genes regulated by FMR4, we found enrichment for those involved in neural development and cellular proliferation. S-phase marker assays further demonstrated that FMR4 may promote cellular proliferation, rather than differentiation, of human neural precursor cells (hNPCs). By establishing this novel function for FMR4 in hNPCs, we lend support to existing evidence of the epigenetic involvement of lncRNA in nervous system development, and increase our understanding of the complex pathogenesis underlying neurological disorders associated with FMR1 repeat expansions.
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Velmeshev D, Lally P, Magistri M, Faghihi MA. CANEapp: a user-friendly application for automated next generation transcriptomic data analysis. BMC Genomics 2016; 17:49. [PMID: 26758513 PMCID: PMC4710974 DOI: 10.1186/s12864-015-2346-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Accepted: 12/22/2015] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND Next generation sequencing (NGS) technologies are indispensable for molecular biology research, but data analysis represents the bottleneck in their application. Users need to be familiar with computer terminal commands, the Linux environment, and various software tools and scripts. Analysis workflows have to be optimized and experimentally validated to extract biologically meaningful data. Moreover, as larger datasets are being generated, their analysis requires use of high-performance servers. RESULTS To address these needs, we developed CANEapp (application for Comprehensive automated Analysis of Next-generation sequencing Experiments), a unique suite that combines a Graphical User Interface (GUI) and an automated server-side analysis pipeline that is platform-independent, making it suitable for any server architecture. The GUI runs on a PC or Mac and seamlessly connects to the server to provide full GUI control of RNA-sequencing (RNA-seq) project analysis. The server-side analysis pipeline contains a framework that is implemented on a Linux server through completely automated installation of software components and reference files. Analysis with CANEapp is also fully automated and performs differential gene expression analysis and novel noncoding RNA discovery through alternative workflows (Cuffdiff and R packages edgeR and DESeq2). We compared CANEapp to other similar tools, and it significantly improves on previous developments. We experimentally validated CANEapp's performance by applying it to data derived from different experimental paradigms and confirming the results with quantitative real-time PCR (qRT-PCR). CANEapp adapts to any server architecture by effectively using available resources and thus handles large amounts of data efficiently. CANEapp performance has been experimentally validated on various biological datasets. CANEapp is available free of charge at http://psychiatry.med.miami.edu/research/laboratory-of-translational-rna-genomics/CANE-app . CONCLUSIONS We believe that CANEapp will serve both biologists with no computational experience and bioinformaticians as a simple, timesaving but accurate and powerful tool to analyze large RNA-seq datasets and will provide foundations for future development of integrated and automated high-throughput genomics data analysis tools. Due to its inherently standardized pipeline and combination of automated analysis and platform-independence, CANEapp is an ideal for large-scale collaborative RNA-seq projects between different institutions and research groups.
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Affiliation(s)
- Dmitry Velmeshev
- Department of Psychiatry, University of Miami Miller School of Medicine, Miami, FL, 33136, USA. .,Department of Biochemistry & Molecular Biology, University of Miami Miller School of Medicine, Miami, FL, 33136, USA.
| | - Patrick Lally
- Department of Psychiatry, University of Miami Miller School of Medicine, Miami, FL, 33136, USA. .,Department of Biomedical Engineering, University of Miami, Coral Gables, FL, 33146, USA.
| | - Marco Magistri
- Department of Psychiatry, University of Miami Miller School of Medicine, Miami, FL, 33136, USA.
| | - Mohammad Ali Faghihi
- Department of Psychiatry, University of Miami Miller School of Medicine, Miami, FL, 33136, USA.
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7
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Yamanaka Y, Faghihi MA, Magistri M, Alvarez-Garcia O, Lotz M, Wahlestedt C. Antisense RNA controls LRP1 Sense transcript expression through interaction with a chromatin-associated protein, HMGB2. Cell Rep 2015; 11:967-976. [PMID: 25937287 DOI: 10.1016/j.celrep.2015.04.011] [Citation(s) in RCA: 72] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Revised: 03/06/2015] [Accepted: 04/03/2015] [Indexed: 12/16/2022] Open
Abstract
Long non-coding RNAs (lncRNAs), including natural antisense transcripts (NATs), are expressed more extensively than previously anticipated and have widespread roles in regulating gene expression. Nevertheless, the molecular mechanisms of action of the majority of NATs remain largely unknown. Here, we identify a NAT of low-density lipoprotein receptor-related protein 1 (Lrp1), referred to as Lrp1-AS, that negatively regulates Lrp1 expression. We show that Lrp1-AS directly binds to high-mobility group box 2 (Hmgb2) and inhibits the activity of Hmgb2 to enhance Srebp1a-dependent transcription of Lrp1. Short oligonucleotides targeting Lrp1-AS inhibit the interaction of antisense transcript and Hmgb2 protein and increase Lrp1 expression by enhancing Hmgb2 activity. Quantitative RT-PCR analysis of brain tissue samples from Alzheimer's disease patients and aged-matched controls revealed upregulation of LRP1-AS and downregulation of LRP1. Our data suggest a regulatory mechanism whereby a NAT interacts with a ubiquitous chromatin-associated protein to modulate its activity in a locus-specific fashion.
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Affiliation(s)
- Yasunari Yamanaka
- Center for Therapeutic Innovation and Department of Psychiatry and Behavioral Sciences, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Mohammad Ali Faghihi
- Center for Therapeutic Innovation and Department of Psychiatry and Behavioral Sciences, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Marco Magistri
- Center for Therapeutic Innovation and Department of Psychiatry and Behavioral Sciences, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Oscar Alvarez-Garcia
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Martin Lotz
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Claes Wahlestedt
- Center for Therapeutic Innovation and Department of Psychiatry and Behavioral Sciences, University of Miami Miller School of Medicine, Miami, FL 33136, USA.
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8
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Xu Y, Wang J, Fu S, Wang Z. Knockdown of CDK2AP1 by RNA interference inhibits cell growth and tumorigenesis of human glioma. Neurol Res 2013; 36:659-65. [DOI: 10.1179/1743132813y.0000000298] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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9
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Civenni G, Malek A, Albino D, Garcia-Escudero R, Napoli S, Di Marco S, Pinton S, Sarti M, Carbone GM, Catapano CV. RNAi-mediated silencing of Myc transcription inhibits stem-like cell maintenance and tumorigenicity in prostate cancer. Cancer Res 2013; 73:6816-27. [PMID: 24063893 DOI: 10.1158/0008-5472.can-13-0615] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Several studies link disease progression, recurrence, and treatment failures to the cancer stem-like cell (CSC) subpopulation within the heterogeneous tumor cell population. Myc is a transcription factor having a central function in stem cell biology and in human cancers. Hence, Myc represents an attractive target to develop CSC-specific therapies. Recent findings suggest that Myc transcription can be silenced using an RNA interference (RNAi)-based strategy that targets noncoding promoter-associated RNA (paRNA) overlapping the transcription start site. In this study, we investigated the effects of silencing Myc transcription on prostate CSC in cell culture and xenograft models of human prostate cancer. Treatment with an effective promoter-targeting siRNA reduced the fraction of CSCs, leading to reduced self-renewal, tumor-initiating, and metastatic capability. Combined analysis of stem-like cells and senescence markers indicated that Myc silencing triggered a phenotypic shift and senescence in the CSC subpopulation. Notably, systemic delivery of the promoter-targeting siRNA in the xenograft model produced a striking suppression in the development of prostate tumors. Our results support a pivotal role for Myc in CSC maintenance and show that Myc targeting via RNAi-based transcriptional silencing can trigger CSC senescence and loss of their tumor-initiating capability. More generally, our findings demonstrate the efficacy of RNAi-based transcriptional strategies and the potential to target regulatory noncoding paRNAs for therapeutic applications.
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Affiliation(s)
- Gianluca Civenni
- Authors' Affiliations: Institute of Oncology Research; Oncology Institute of Southern Switzerland, Bellinzona, Switzerland; and Molecular Oncology Unit, CIEMAT, Madrid, Spain
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10
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Malek A. RNA networks in ovarian cancer. Methods Mol Biol 2013; 1049:111-117. [PMID: 23913213 DOI: 10.1007/978-1-62703-547-7_10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Development of ovarian cancer is known to be associated with alterations in the expression of cellular RNAs. Most of the clinical and biological characteristics of ovarian cancer have been correlated with significant changes in the expression of a subset of genes. Over the last few years, considerable resources have been focused on understanding the complex structure and function of noncoding RNAs, and this paradigm is also applicable to ovarian cancer research. The chapter provides a brief review of methodological approaches used to study alterations in protein coding and noncoding RNAs in the context of ovarian cancer.
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Affiliation(s)
- Anastasia Malek
- Laboratory of Oncoendocrinology, NN Petrov Institute of Oncology, St. Petersburg, Russia
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Matsui M, Sakurai F, Elbashir S, Foster D, Manoharan M, Corey DR. Activation of LDL receptor expression by small RNAs complementary to a noncoding transcript that overlaps the LDLR promoter. CHEMISTRY & BIOLOGY 2010; 17:1344-55. [PMID: 21168770 PMCID: PMC3071588 DOI: 10.1016/j.chembiol.2010.10.009] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2010] [Revised: 09/30/2010] [Accepted: 10/12/2010] [Indexed: 11/15/2022]
Abstract
Low-density lipoprotein receptor (LDLR) is a cell-surface receptor that plays a central role in regulating cholesterol levels. Increased levels of LDLR would lead to reduced cholesterol levels and contribute to strategies designed to treat hypercholesterolemia. We have previously shown that duplex RNAs complementary to transcription start sites can associate with noncoding transcripts and activate gene expression. Here we show that duplex RNAs complementary to the promoter of LDLR activate expression of LDLR and increase the display of LDLR on the surface of liver cells. Activation requires complementarity to the LDLR promoter and can be achieved by chemically modified duplex RNAs. Promoter-targeted duplex RNAs can overcome repression of LDLR expression by 25-hydroxycholesterol and do not interfere with activation of LDLR expression by lovastatin. These data demonstrate that small RNAs can activate LDLR expression and affect LDLR function.
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Affiliation(s)
- Masayuki Matsui
- Departments of Pharmacology and Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX 75390-9041, USA
| | - Fuminori Sakurai
- Department of Biochemistry and Molecular Biology, Graduate School of Pharmaceutical Sciences, Osaka University, Osaka 565-0871, Japan
| | | | | | | | - David R. Corey
- Departments of Pharmacology and Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX 75390-9041, USA
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