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Salvato I, Ricciardi L, Nucera F, Nigro A, Dal Col J, Monaco F, Caramori G, Stellato C. RNA-Binding Proteins as a Molecular Link between COPD and Lung Cancer. COPD 2023; 20:18-30. [PMID: 36655862 DOI: 10.1080/15412555.2022.2107500] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Chronic obstructive pulmonary disease (COPD) represents an independent risk factor for lung cancer development. Accelerated cell senescence, induced by oxidative stress and inflammation, is a common pathogenic determinant of both COPD and lung cancer. The post transcriptional regulation of genes involved in these processes is finely regulated by RNA-binding proteins (RBPs), which regulate mRNA turnover, subcellular localization, splicing and translation. Multiple pro-inflammatory mediators (including cytokines, chemokines, proteins, growth factors and others), responsible of lung microenvironment alteration, are regulated by RBPs. Several mouse models have shown the implication of RBPs in multiple mechanisms that sustain chronic inflammation and neoplastic transformation. However, further studies are required to clarify the role of RBPs in the pathogenic mechanisms shared by lung cancer and COPD, in order to identify novel biomarkers and therapeutic targets. This review will therefore focus on the studies collectively indicating the role of RBPs in oxidative stress and chronic inflammation as common pathogenic mechanisms shared by lung cancer and COPD.
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Affiliation(s)
- Ilaria Salvato
- Pneumologia, Dipartimento di Scienze Biomediche, Odontoiatriche e delle Immagini Morfologiche e Funzionali (BIOMORF), Università degli Studi di Messina, Italy
| | - Luca Ricciardi
- Pneumologia, Dipartimento di Scienze Biomediche, Odontoiatriche e delle Immagini Morfologiche e Funzionali (BIOMORF), Università degli Studi di Messina, Italy
| | - Francesco Nucera
- Pneumologia, Dipartimento di Scienze Biomediche, Odontoiatriche e delle Immagini Morfologiche e Funzionali (BIOMORF), Università degli Studi di Messina, Italy
| | - Annunziata Nigro
- Department of Medicine, Surgery and Dentistry "Scuola Medica Salernitana", University of Salerno, Salerno, Italy
| | - Jessica Dal Col
- Department of Medicine, Surgery and Dentistry "Scuola Medica Salernitana", University of Salerno, Salerno, Italy
| | - Francesco Monaco
- Chirurgia Toracica, Dipartimento di Scienze Biomediche, Odontoiatriche e delle Immagini Morfologiche e Funzionali (BIOMORF), Università degli Studi di Messina, Italy
| | - Gaetano Caramori
- Pneumologia, Dipartimento di Scienze Biomediche, Odontoiatriche e delle Immagini Morfologiche e Funzionali (BIOMORF), Università degli Studi di Messina, Italy
| | - Cristiana Stellato
- Department of Medicine, Surgery and Dentistry "Scuola Medica Salernitana", University of Salerno, Salerno, Italy
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2
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Joseph BP, Weber V, Knüpfer L, Giorgetti A, Alfonso-Prieto M, Krauß S, Carloni P, Rossetti G. Low Molecular Weight Inhibitors Targeting the RNA-Binding Protein HuR. Int J Mol Sci 2023; 24:13127. [PMID: 37685931 PMCID: PMC10488267 DOI: 10.3390/ijms241713127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 08/18/2023] [Accepted: 08/22/2023] [Indexed: 09/10/2023] Open
Abstract
The RNA-binding protein human antigen R (HuR) regulates stability, translation, and nucleus-to-cytoplasm shuttling of its target mRNAs. This protein has been progressively recognized as a relevant therapeutic target for several pathologies, like cancer, neurodegeneration, as well as inflammation. Inhibitors of mRNA binding to HuR might thus be beneficial against a variety of diseases. Here, we present the rational identification of structurally novel HuR inhibitors. In particular, by combining chemoinformatic approaches, high-throughput virtual screening, and RNA-protein pulldown assays, we demonstrate that the 4-(2-(2,4,6-trioxotetrahydropyrimidin-5(2H)-ylidene)hydrazineyl)benzoate ligand exhibits a dose-dependent HuR inhibition effect in binding experiments. Importantly, the chemical scaffold is new with respect to the currently known HuR inhibitors, opening up a new avenue for the design of pharmaceutical agents targeting this important protein.
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Affiliation(s)
- Benjamin Philipp Joseph
- Institute for Neuroscience and Medicine and Institute for Advanced Simulations (INM-9/IAS-5), Computational Biomedicine, Forschungszentrum Jülich, 52425 Jülich, Germany; (B.P.J.); (V.W.); (A.G.); (M.A.-P.); (G.R.)
- Faculty of Mathematics, Computer Science and Natural Sciences, RWTH Aachen University, 52062 Aachen, Germany
| | - Verena Weber
- Institute for Neuroscience and Medicine and Institute for Advanced Simulations (INM-9/IAS-5), Computational Biomedicine, Forschungszentrum Jülich, 52425 Jülich, Germany; (B.P.J.); (V.W.); (A.G.); (M.A.-P.); (G.R.)
- Faculty of Mathematics, Computer Science and Natural Sciences, RWTH Aachen University, 52062 Aachen, Germany
| | - Lisa Knüpfer
- Institute of Biology, University of Siegen, 57076 Siegen, Germany;
| | - Alejandro Giorgetti
- Institute for Neuroscience and Medicine and Institute for Advanced Simulations (INM-9/IAS-5), Computational Biomedicine, Forschungszentrum Jülich, 52425 Jülich, Germany; (B.P.J.); (V.W.); (A.G.); (M.A.-P.); (G.R.)
- Department of Biotechnology, University of Verona, 37134 Verona, Italy
| | - Mercedes Alfonso-Prieto
- Institute for Neuroscience and Medicine and Institute for Advanced Simulations (INM-9/IAS-5), Computational Biomedicine, Forschungszentrum Jülich, 52425 Jülich, Germany; (B.P.J.); (V.W.); (A.G.); (M.A.-P.); (G.R.)
| | - Sybille Krauß
- Institute of Biology, University of Siegen, 57076 Siegen, Germany;
| | - Paolo Carloni
- Institute for Neuroscience and Medicine and Institute for Advanced Simulations (INM-9/IAS-5), Computational Biomedicine, Forschungszentrum Jülich, 52425 Jülich, Germany; (B.P.J.); (V.W.); (A.G.); (M.A.-P.); (G.R.)
- Faculty of Mathematics, Computer Science and Natural Sciences, RWTH Aachen University, 52062 Aachen, Germany
| | - Giulia Rossetti
- Institute for Neuroscience and Medicine and Institute for Advanced Simulations (INM-9/IAS-5), Computational Biomedicine, Forschungszentrum Jülich, 52425 Jülich, Germany; (B.P.J.); (V.W.); (A.G.); (M.A.-P.); (G.R.)
- Jülich Supercomputing Centre (JSC), Forschungszentrum Jülich, 52425 Jülich, Germany
- Department of Neurology, RWTH Aachen University, 44517 Aachen, Germany
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3
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Xiang M, Liu L, Wu T, Wei B, Liu H. RNA-binding proteins in degenerative joint diseases: A systematic review. Ageing Res Rev 2023; 86:101870. [PMID: 36746279 DOI: 10.1016/j.arr.2023.101870] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2022] [Revised: 01/12/2023] [Accepted: 01/27/2023] [Indexed: 02/07/2023]
Abstract
RNA-binding proteins (RBPs), which are conserved proteins comprising multiple intermediate sequences, can interact with proteins, messenger RNA (mRNA) of coding genes, and non-coding RNAs to perform different biological functions, such as the regulation of mRNA stability, selective polyadenylation, and the management of non-coding microRNA (miRNA) synthesis to affect downstream targets. This article will highlight the functions of RBPs, in degenerative joint diseases (intervertebral disc degeneration [IVDD] and osteoarthritis [OA]). It will reviews the latest advancements on the regulatory mechanism of RBPs in degenerative joint diseases, in order to understand the pathophysiology, early diagnosis and treatment of OA and IVDD from a new perspective.
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Affiliation(s)
- Min Xiang
- Department of Orthopedics, Affiliated Hospital of Guangdong Medical University, Zhanjiang 524001, China
| | - Ling Liu
- Department of Pediatrics, Affiliated Hospital of Guangdong Medical University, Zhanjiang 524001, China
| | - Tingrui Wu
- Department of Orthopedics, Affiliated Hospital of Guangdong Medical University, Zhanjiang 524001, China
| | - Bo Wei
- Department of Orthopedics, Affiliated Hospital of Guangdong Medical University, Zhanjiang 524001, China.
| | - Huan Liu
- Department of Orthopedics, Affiliated Traditional Chinese Medicine Hospital of Southwest Medical University, Luzhou 646000, China.
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4
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Hong D, Jeong S. 3'UTR Diversity: Expanding Repertoire of RNA Alterations in Human mRNAs. Mol Cells 2023; 46:48-56. [PMID: 36697237 PMCID: PMC9880603 DOI: 10.14348/molcells.2023.0003] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2023] [Revised: 01/05/2023] [Accepted: 01/08/2023] [Indexed: 01/27/2023] Open
Abstract
Genomic information stored in the DNA is transcribed to the mRNA and translated to proteins. The 3' untranslated regions (3'UTRs) of the mRNA serve pivotal roles in posttranscriptional gene expression, regulating mRNA stability, translation, and localization. Similar to DNA mutations producing aberrant proteins, RNA alterations expand the transcriptome landscape and change the cellular proteome. Recent global analyses reveal that many genes express various forms of altered RNAs, including 3'UTR length variants. Alternative polyadenylation and alternative splicing are involved in diversifying 3'UTRs, which could act as a hidden layer of eukaryotic gene expression control. In this review, we summarize the functions and regulations of 3'UTRs and elaborate on the generation and functional consequences of 3'UTR diversity. Given that dynamic 3'UTR length control contributes to phenotypic complexity, dysregulated 3'UTR diversity might be relevant to disease development, including cancers. Thus, 3'UTR diversity in cancer could open exciting new research areas and provide avenues for novel cancer theragnostics.
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Affiliation(s)
- Dawon Hong
- Laboratory of RNA Cell Biology, Department of Bioconvergence Engineering, Dankook University Graduate School, Yongin 16892, Korea
| | - Sunjoo Jeong
- Laboratory of RNA Cell Biology, Department of Bioconvergence Engineering, Dankook University Graduate School, Yongin 16892, Korea
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5
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Sobolewski C, Dubuquoy L, Legrand N. MicroRNAs, Tristetraprolin Family Members and HuR: A Complex Interplay Controlling Cancer-Related Processes. Cancers (Basel) 2022; 14:cancers14143516. [PMID: 35884580 PMCID: PMC9319505 DOI: 10.3390/cancers14143516] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 07/15/2022] [Accepted: 07/18/2022] [Indexed: 12/17/2022] Open
Abstract
Simple Summary AU-rich Element Binding Proteins (AUBPs) represent important post-transcriptional regulators of gene expression by regulating mRNA decay and/or translation. Importantly, AUBPs can interfere with microRNA-dependent regulation by (i) competing with the same binding sites on mRNA targets, (ii) sequestering miRNAs, thereby preventing their binding to their specific targets or (iii) promoting miRNA-dependent regulation. These data highlight a new paradigm where both miRNA and RNA binding proteins form a complex regulatory network involved in physiological and pathological processes. However, this interplay is still poorly considered, and our current models do not integrate this level of complexity, thus potentially giving misleading interpretations regarding the role of these regulators in human cancers. This review summarizes the current knowledge regarding the crosstalks existing between HuR, tristetraprolin family members and microRNA-dependent regulation. Abstract MicroRNAs represent the most characterized post-transcriptional regulators of gene expression. Their altered expression importantly contributes to the development of a wide range of metabolic and inflammatory diseases but also cancers. Accordingly, a myriad of studies has suggested novel therapeutic approaches aiming at inhibiting or restoring the expression of miRNAs in human diseases. However, the influence of other trans-acting factors, such as long-noncoding RNAs or RNA-Binding-Proteins, which compete, interfere, or cooperate with miRNAs-dependent functions, indicate that this regulatory mechanism is much more complex than initially thought, thus questioning the current models considering individuals regulators. In this review, we discuss the interplay existing between miRNAs and the AU-Rich Element Binding Proteins (AUBPs), HuR and tristetraprolin family members (TTP, BRF1 and BRF2), which importantly control the fate of mRNA and whose alterations have also been associated with the development of a wide range of chronic disorders and cancers. Deciphering the interplay between these proteins and miRNAs represents an important challenge to fully characterize the post-transcriptional regulation of pro-tumorigenic processes and design new and efficient therapeutic approaches.
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6
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Gao H, Lin Y, Huang C, Li X, Diamond MS, Liu C, Zhang R, Zhang P. A genome-wide CRISPR screen identifies HuR as a regulator of apoptosis induced by dsRNA and virus. J Cell Sci 2022; 135:274702. [PMID: 35112703 DOI: 10.1242/jcs.258855] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Accepted: 01/24/2022] [Indexed: 11/20/2022] Open
Abstract
We performed an unbiased whole-genome CRISPR/Cas9 screen in A549 cells to identify potential regulators involved in cell death triggered by dsRNA. Of several top candidate genes, we identified the RNA binding protein ELAV like protein 1 (ELAVL1) that encodes Hu antigen R (HuR). Depletion of HuR led to less cell death induced by dsRNA. HuR is mainly involved in the apoptosis, and all of its RNA recognition motifs are essential for its proapoptotic function. We further showed that the HuR depletion had no influence on the mRNA level of an anti-apoptotic gene, BCL2, instead downregulated its translation in a cap-independent way. Polysome fractionation studies showed that HuR retarded the BCL2 mRNA in the non-translating pool of polysomes. Moreover, protection from dsRNA-induced apoptosis by HuR depletion required the presence of BCL2, indicating that the proapoptotic function of HuR is executed by suppressing BCL2. Consistently, HuR regulated apoptosis induced by infection of encephalomyocarditis or Semliki Forest virus. Collectively, our work identified a suite of proteins that regulate dsRNA-induced cell death, and elucidated the mechanism by which HuR acts as a pro-apoptotic factor.
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Affiliation(s)
- Huixin Gao
- Key Laboratory of Tropical Diseases Control (Sun Yat-sen University), Ministry of Education, Guangzhou 510080, China.,Department of Immunology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China
| | - Yuxia Lin
- Key Laboratory of Tropical Diseases Control (Sun Yat-sen University), Ministry of Education, Guangzhou 510080, China.,Department of Immunology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China
| | - Changbai Huang
- Key Laboratory of Tropical Diseases Control (Sun Yat-sen University), Ministry of Education, Guangzhou 510080, China.,Department of Immunology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China
| | - Xiaobo Li
- Key Laboratory of Tropical Diseases Control (Sun Yat-sen University), Ministry of Education, Guangzhou 510080, China.,Department of Immunology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China
| | - Michael S Diamond
- Departments of Medicine, Molecular Microbiology, Pathology & Immunology, Washington University School of Medicine, Saint Louis, MO, USA
| | - Chao Liu
- Key Laboratory of Tropical Diseases Control (Sun Yat-sen University), Ministry of Education, Guangzhou 510080, China.,Department of Microbiology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China
| | - Rong Zhang
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai, 200032, China
| | - Ping Zhang
- Key Laboratory of Tropical Diseases Control (Sun Yat-sen University), Ministry of Education, Guangzhou 510080, China.,Department of Immunology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China
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7
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Guha A, Waris S, Nabors LB, Filippova N, Gorospe M, Kwan T, King PH. The versatile role of HuR in Glioblastoma and its potential as a therapeutic target for a multi-pronged attack. Adv Drug Deliv Rev 2022; 181:114082. [PMID: 34923029 PMCID: PMC8916685 DOI: 10.1016/j.addr.2021.114082] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 10/15/2021] [Accepted: 12/12/2021] [Indexed: 02/03/2023]
Abstract
Glioblastoma (GBM) is a malignant and aggressive brain tumor with a median survival of ∼15 months. Resistance to treatment arises from the extensive cellular and molecular heterogeneity in the three major components: glioma tumor cells, glioma stem cells, and tumor-associated microglia and macrophages. Within this triad, there is a complex network of intrinsic and secreted factors that promote classic hallmarks of cancer, including angiogenesis, resistance to cell death, proliferation, and immune evasion. A regulatory node connecting these diverse pathways is at the posttranscriptional level as mRNAs encoding many of the key drivers contain adenine- and uridine rich elements (ARE) in the 3' untranslated region. Human antigen R (HuR) binds to ARE-bearing mRNAs and is a major positive regulator at this level. This review focuses on basic concepts of ARE-mediated RNA regulation and how targeting HuR with small molecule inhibitors represents a plausible strategy for a multi-pronged therapeutic attack on GBM.
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Affiliation(s)
- Abhishek Guha
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL 35294, United States
| | - Saboora Waris
- Shaheed Zulfiqar Ali Bhutto Medical University, PIMS, G-8, Islamabad, Pakistan
| | - Louis B Nabors
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL 35294, United States
| | - Natalia Filippova
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL 35294, United States
| | - Myriam Gorospe
- Laboratory of Genetics and Genomics, National Institute on Aging Intramural Research Program, National Institutes of Health, Baltimore, MD 21224, United States
| | - Thaddaeus Kwan
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL 35294, United States
| | - Peter H King
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL 35294, United States; Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL 35294, United States; Birmingham Veterans Affairs Medical Center, Birmingham, AL 35294, United States.
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8
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Trivlidis J, Aloufi N, Al-Habeeb F, Nair P, Azuelos I, Eidelman DH, Baglole CJ. HuR drives lung fibroblast differentiation but not metabolic reprogramming in response to TGF-β and hypoxia. Respir Res 2021; 22:323. [PMID: 34963461 PMCID: PMC8715577 DOI: 10.1186/s12931-021-01916-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Accepted: 12/14/2021] [Indexed: 11/10/2022] Open
Abstract
Background Pulmonary fibrosis is thought to be driven by recurrent alveolar epithelial injury which leads to the differentiation of fibroblasts into α-smooth muscle actin (α-SMA)-expressing myofibroblasts and subsequent deposition of extracellular matrix (ECM). Transforming growth factor beta-1 (TGF-β1) plays a key role in fibroblast differentiation, which we have recently shown involves human antigen R (HuR). HuR is an RNA binding protein that also increases the translation of hypoxia inducible factor (HIF-1α) mRNA, a transcription factor critical for inducing a metabolic shift from oxidative phosphorylation towards glycolysis. This metabolic shift may cause fibroblast differentiation. We hypothesized that under hypoxic conditions, HuR controls myofibroblast differentiation and glycolytic reprogramming in human lung fibroblasts (HLFs). Methods Primary HLFs were cultured in the presence (or absence) of TGF-β1 (5 ng/ml) under hypoxic (1% O2) or normoxic (21% O2) conditions. Evaluation included mRNA and protein expression of glycolytic and myofibroblast/ECM markers by qRT-PCR and western blot. Metabolic profiling was done by proton nuclear magnetic resonance (1H- NMR). Separate experiments were conducted to evaluate the effect of HuR on metabolic reprogramming using siRNA-mediated knock-down. Results Hypoxia alone had no significant effect on fibroblast differentiation or metabolic reprogramming. While hypoxia- together with TGFβ1- increased mRNA levels of differentiation and glycolysis genes, such as ACTA2, LDHA, and HK2, protein levels of α-SMA and collagen 1 were significantly reduced. Hypoxia induced cytoplasmic translocation of HuR. Knockdown of HuR reduced features of fibroblast differentiation in response to TGF-β1 with and without hypoxia, including α-SMA and the ECM marker collagen I, but had no effect on lactate secretion. Conclusions Hypoxia reduced myofibroblasts differentiation and lactate secretion in conjunction with TGF-β. HuR is an important protein in the regulation of myofibroblast differentiation but does not control glycolysis in HLFs in response to hypoxia. More research is needed to understand the functional implications of HuR in IPF pathogenesis.
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9
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Borgonetti V, Coppi E, Galeotti N. Targeting the RNA-Binding Protein HuR as Potential Thera-Peutic Approach for Neurological Disorders: Focus on Amyo-Trophic Lateral Sclerosis (ALS), Spinal Muscle Atrophy (SMA) and Multiple Sclerosis. Int J Mol Sci 2021; 22:ijms221910394. [PMID: 34638733 PMCID: PMC8508990 DOI: 10.3390/ijms221910394] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 09/22/2021] [Accepted: 09/24/2021] [Indexed: 01/03/2023] Open
Abstract
The importance of precise co- and post-transcriptional processing of RNA in the regulation of gene expression has become increasingly clear. RNA-binding proteins (RBPs) are a class of proteins that bind single- or double-chain RNA, with different affinities and selectivity, thus regulating the various functions of RNA and the fate of the cells themselves. ELAV (embryonic lethal/abnormal visual system)/Hu proteins represent an important family of RBPs and play a key role in the fate of newly transcribed mRNA. ELAV proteins bind AU-rich element (ARE)-containing transcripts, which are usually present on the mRNA of proteins such as cytokines, growth factors, and other proteins involved in neuronal differentiation and maintenance. In this review, we focused on a member of ELAV/Hu proteins, HuR, and its role in the development of neurodegenerative disorders, with a particular focus on demyelinating diseases.
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10
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Nuvoli B, Antoniani B, Libener R, Maconi A, Sacconi A, Carosi M, Galati R. Identification of novel COX-2 / CYP19A1 axis involved in the mesothelioma pathogenesis opens new therapeutic opportunities. JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH : CR 2021; 40:257. [PMID: 34404424 PMCID: PMC8369782 DOI: 10.1186/s13046-021-02050-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Accepted: 07/23/2021] [Indexed: 01/12/2023]
Abstract
BACKGROUND Based on previous studies highlighting that the induction of cyclooxygenase-2 (COX-2) and high prostaglandin E2 (PGE2) levels contribute to the pathogenesis of malignant pleural mesothelioma (MPM), and that aromatase (CYP19A1), an enzyme that plays a key role in estrogen biosynthesis, along with estradiol (E2) were expressed in MPM, this study aimed to investigate the possible interplay between COX-2 and CYP19A1 in the pathogenesis of mesothelioma, as well as the underlying mechanism. METHODS The interaction between COX-2 and CYP19A1 was first investigated on different MPM lines upon PGE2, and COX-2 inhibitor (rofecoxib) treatment by western blot, RT-PCR. The key regulatory pathways involved in the COX-2 and CYP19A1 axis were further studied in MPM cells, after rofecoxib and exemestane (CYP19A1 inhibitor) treatment in monotherapy and in combination, by cell cycle distribution, western blot, and combination index analysis. To explore the role of COX-2/CYP19A1 axis in 3D preclinical models of MPM cells, we analyzed the effect of combination of COX-2 and CYP19A1 inhibitors in mesosphere formation. Immunohistochemical analysis of MPM mesosphere and specimens was utilized to evaluate the involvement of COX-2 on the CYP19A1 activity and the relationship between E2 and COX-2. RESULTS PGE2 or rofecoxib treatment caused in MPM cells an increased or decreased, respectively, CYP19A1 expression at mRNA and protein levels. The effect of rofecoxib and exemestane combination in MPM cell proliferation was synergistic. Activation of caspase-3 and cleavage of PARP confirmed an apoptotic death for MPM cell lines. Increased expression levels of p53, p21, and p27, downregulation of cyclin D1 and inhibition of Akt activation (pAKT) were also found. The antagonistic effect of rofecoxib and exemestane combination found only in one cell line, was reverted by pretreatment with MK2206, a pAKT inhibitor, indicating pAKT as an actionable mediator in the COX-2-CYP19A1 axis. Reduction of size and sphere-forming efficiency in MPM spheres after treatment with both inhibitor and a decrease in COX-2 and E2 staining was found. Moreover, immunohistochemical analysis of 46 MPM samples showed a significant positive correlation between COX-2 and E2. CONCLUSIONS Collectively, the results highlighted a novel COX-2/CYP19A1 axis in the pathogenesis of MPM that can be pharmacologically targeted, consequently opening up new therapeutic options.
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Affiliation(s)
- Barbara Nuvoli
- grid.417520.50000 0004 1760 5276Preclinical Models and New Therapeutic Agents Unit, IRCCS Regina Elena National Cancer Institute, Rome, Italy
| | - Barbara Antoniani
- grid.417520.50000 0004 1760 5276Anatomy Pathology Unit, IRCCS Regina Elena National Cancer Institute, Rome, Italy
| | - Roberta Libener
- Department of Integrated Activities Research and Innovation, SS Antonio and Biagio General Hospital, Alessandria, Italy
| | - Antonio Maconi
- Department of Integrated Activities Research and Innovation, SS Antonio and Biagio General Hospital, Alessandria, Italy
| | - Andrea Sacconi
- grid.417520.50000 0004 1760 5276Clinical Trial Center, Biostatistics and Bioinformatics Unit, IRCCS Regina Elena National Cancer Institute, Rome, Italy
| | - Mariantonia Carosi
- grid.417520.50000 0004 1760 5276Anatomy Pathology Unit, IRCCS Regina Elena National Cancer Institute, Rome, Italy
| | - Rossella Galati
- grid.417520.50000 0004 1760 5276Preclinical Models and New Therapeutic Agents Unit, IRCCS Regina Elena National Cancer Institute, Rome, Italy
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11
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Al-Habeeb F, Aloufi N, Traboulsi H, Liu X, Nair P, Haston C, Azuelos I, Huang SK, White ES, Gallouzi IE, Di Marco S, Eidelman DH, Baglole CJ. Human antigen R promotes lung fibroblast differentiation to myofibroblasts and increases extracellular matrix production. J Cell Physiol 2021; 236:6836-6851. [PMID: 33855709 DOI: 10.1002/jcp.30380] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Revised: 03/13/2021] [Accepted: 03/16/2021] [Indexed: 01/12/2023]
Abstract
Idiopathic pulmonary fibrosis (IPF) is a disease of progressive scarring caused by excessive extracellular matrix (ECM) deposition and activation of α-SMA-expressing myofibroblasts. Human antigen R (HuR) is an RNA binding protein that promotes protein translation. Upon translocation from the nucleus to the cytoplasm, HuR functions to stabilize messenger RNA (mRNA) to increase protein levels. However, the role of HuR in promoting ECM production, myofibroblast differentiation, and lung fibrosis is unknown. Human lung fibroblasts (HLFs) treated with transforming growth factor β1 (TGF-β1) showed a significant increase in translocation of HuR from the nucleus to the cytoplasm. TGF-β-treated HLFs that were transfected with HuR small interfering RNA had a significant reduction in α-SMA protein as well as the ECM proteins COL1A1, COL3A, and FN1. HuR was also bound to mRNA for ACTA2, COL1A1, COL3A1, and FN. HuR knockdown affected the mRNA stability of ACTA2 but not that of the ECM genes COL1A1, COL3A1, or FN. In mouse models of pulmonary fibrosis, there was higher cytoplasmic HuR in lung structural cells compared to control mice. In human IPF lungs, there was also more cytoplasmic HuR. This study is the first to show that HuR in lung fibroblasts controls their differentiation to myofibroblasts and consequent ECM production. Further research on HuR could assist in establishing the basis for the development of new target therapy for fibrotic diseases, such as IPF.
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Affiliation(s)
- Fatmah Al-Habeeb
- Translational Research in Respiratory Diseases Program, Research Institute of the McGill University Health Centre, Montreal, Quebec, Canada.,Department of Medicine, McGill University, Montreal, Quebec, Canada
| | - Noof Aloufi
- Translational Research in Respiratory Diseases Program, Research Institute of the McGill University Health Centre, Montreal, Quebec, Canada.,Departments of Pathology, McGill University, Montreal, Quebec, Canada
| | - Hussein Traboulsi
- Translational Research in Respiratory Diseases Program, Research Institute of the McGill University Health Centre, Montreal, Quebec, Canada.,Department of Medicine, McGill University, Montreal, Quebec, Canada
| | - Xingxing Liu
- Translational Research in Respiratory Diseases Program, Research Institute of the McGill University Health Centre, Montreal, Quebec, Canada
| | - Parameswaran Nair
- Department of Medicine, McMaster University & St Joseph's Healthcare, Hamilton, Ontario, Canada
| | - Christina Haston
- Department of Computer Science, Mathematics, Physics and Statistics, University of British Columbia, British Columbia, Canada
| | - Ilan Azuelos
- Translational Research in Respiratory Diseases Program, Research Institute of the McGill University Health Centre, Montreal, Quebec, Canada.,Department of Medicine, McGill University, Montreal, Quebec, Canada
| | - Steven K Huang
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Eric S White
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Imed E Gallouzi
- Department of Biochemistry, McGill University, Montreal, Quebec, Canada.,Faculty of Medicine, Goodman Cancer Centre, McGill University, Montreal, Quebec, Canada
| | - Sergio Di Marco
- Department of Biochemistry, McGill University, Montreal, Quebec, Canada.,Faculty of Medicine, Goodman Cancer Centre, McGill University, Montreal, Quebec, Canada
| | - David H Eidelman
- Department of Medicine, McGill University, Montreal, Quebec, Canada
| | - Carolyn J Baglole
- Translational Research in Respiratory Diseases Program, Research Institute of the McGill University Health Centre, Montreal, Quebec, Canada.,Department of Medicine, McGill University, Montreal, Quebec, Canada.,Departments of Pathology, McGill University, Montreal, Quebec, Canada.,Department of Pharmacology & Therapeutics, McGill University, Montreal, Quebec, Canada
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12
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Hegde M, Joshi MB. Comprehensive analysis of regulation of DNA methyltransferase isoforms in human breast tumors. J Cancer Res Clin Oncol 2021; 147:937-971. [PMID: 33604794 PMCID: PMC7954751 DOI: 10.1007/s00432-021-03519-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Accepted: 01/10/2021] [Indexed: 12/14/2022]
Abstract
Significant reprogramming of epigenome is widely described during pathogenesis of breast cancer. Transformation of normal cell to hyperplastic cell and to neoplastic phenotype is associated with aberrant DNA (de)methylation, which, through promoter and enhancer methylation changes, activates oncogenes and silence tumor suppressor genes in variety of tumors including breast. DNA methylation, one of the major epigenetic mechanisms is catalyzed by evolutionarily conserved isoforms namely, DNMT1, DNMT3A and DNMT3B in humans. Over the years, studies have demonstrated intricate and complex regulation of DNMT isoforms at transcriptional, translational and post-translational levels. The recent findings of allosteric regulation of DNMT isoforms and regulation by other interacting chromatin modifying proteins emphasizes functional integrity and their contribution for the development of breast cancer and progression. DNMT isoforms are regulated by several intrinsic and extrinsic parameters. In the present review, we have extensively performed bioinformatics analysis of expression of DNMT isoforms along with their transcriptional and post-transcriptional regulators such as transcription factors, interacting proteins, hormones, cytokines and dietary elements along with their significance during pathogenesis of breast tumors. Our review manuscript provides a comprehensive understanding of key factors regulating DNMT isoforms in breast tumor pathology and documents unsolved issues.
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Affiliation(s)
- Mangala Hegde
- Manipal School of Life Sciences, Manipal Academy of Higher Education, Planetarium Complex, Manipal, 576104, India
| | - Manjunath B Joshi
- Manipal School of Life Sciences, Manipal Academy of Higher Education, Planetarium Complex, Manipal, 576104, India.
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13
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Abstract
The protein-coding regions of mRNAs have the information to make proteins and hence have been at the center of attention for understanding altered protein functions in disease states, including cancer. Indeed, the discovery of genomic alterations and driver mutations that change protein levels and/or activity has been pivotal in our understanding of cancer biology. However, to better understand complex molecular mechanisms that are deregulated in cancers, we also need to look at non-coding parts of mRNAs, including 3'UTRs (untranslated regions), which control mRNA stability, localization, and translation efficiency. Recently, these rather overlooked regions of mRNAs are gaining attention as mounting evidence provides functional links between 3'UTRs, protein functions, and cancer-related molecular mechanisms. Here, roles of 3'UTRs in cancer biology and mechanisms that result in cancer-specific 3'-end isoform variants will be reviewed. An increased appreciation of 3'UTRs may help the discovery of new ways to explain as of yet unknown oncogene activation and tumor suppressor inactivation cases in cancers, and provide new avenues for diagnostic and therapeutic applications.
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Affiliation(s)
- Ayse Elif Erson-Bensan
- Department of Biological Sciences and Cancer Systems Biology Laboratory, Middle East Technical University (METU, ODTU), Dumlupinar Blv No: 1, Universiteler Mah, 06800, Ankara, Turkey.
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14
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Filippova N, Nabors LB. ELAVL1 Role in Cell Fusion and Tunneling Membrane Nanotube Formations with Implication to Treat Glioma Heterogeneity. Cancers (Basel) 2020; 12:E3069. [PMID: 33096700 PMCID: PMC7590168 DOI: 10.3390/cancers12103069] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Revised: 10/15/2020] [Accepted: 10/18/2020] [Indexed: 12/16/2022] Open
Abstract
Homotypic and heterotypic cell fusions via permanent membrane fusions and temporal tunneling nanotube formations in the glioma microenvironment were recently documented in vitro and in vivo and mediate glioma survival, plasticity, and recurrence. Chronic inflammation, a hypoxic environment, aberrant mitochondrial function, and ER stress due to unfolded protein accumulation upregulate cell fusion events, which leads to tumor heterogeneity and represents an adaptive mechanism to promote tumor cell survival and plasticity in cytotoxic, nutrient-deprived, mechanically stressed, and inflammatory microenvironments. Cell fusion is a multistep process, which consists of the activation of the cellular stress response, autophagy formation, rearrangement of cytoskeletal architecture in the areas of cell-to-cell contacts, and the expression of proinflammatory cytokines and fusogenic proteins. The mRNA-binding protein of ELAV-family HuR is a critical node, which orchestrates the stress response, autophagy formation, cytoskeletal architecture, and the expression of proinflammatory cytokines and fusogenic proteins. HuR is overexpressed in gliomas and is associated with poor prognosis and treatment resistance. Our review provides a link between the HuR role in the regulation of cell fusion and tunneling nanotube formations in the glioma microenvironment and the potential suppression of these processes by different classes of HuR inhibitors.
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Affiliation(s)
- Natalia Filippova
- Department of Neurology, School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Louis B. Nabors
- Department of Neurology, School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
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15
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Cao J, Cowan DB, Wang DZ. tRNA-Derived Small RNAs and Their Potential Roles in Cardiac Hypertrophy. Front Pharmacol 2020; 11:572941. [PMID: 33041815 PMCID: PMC7527594 DOI: 10.3389/fphar.2020.572941] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Accepted: 08/28/2020] [Indexed: 12/21/2022] Open
Abstract
Transfer RNAs (tRNAs) are abundantly expressed, small non-coding RNAs that have long been recognized as essential components of the protein translation machinery. The tRNA-derived small RNAs (tsRNAs), including tRNA halves (tiRNAs), and tRNA fragments (tRFs), were unexpectedly discovered and have been implicated in a variety of important biological functions such as cell proliferation, cell differentiation, and apoptosis. Mechanistically, tsRNAs regulate mRNA destabilization and translation, as well as retro-element reverse transcriptional and post-transcriptional processes. Emerging evidence has shown that tsRNAs are expressed in the heart, and their expression can be induced by pathological stress, such as hypertrophy. Interestingly, cardiac pathophysiological conditions, such as oxidative stress, aging, and metabolic disorders can be viewed as inducers of tsRNA biogenesis, which further highlights the potential involvement of tsRNAs in these conditions. There is increasing enthusiasm for investigating the molecular and biological functions of tsRNAs in the heart and their role in cardiovascular disease. It is anticipated that this new class of small non-coding RNAs will offer new perspectives in understanding disease mechanisms and may provide new therapeutic targets to treat cardiovascular disease.
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Affiliation(s)
- Jun Cao
- Department of Cardiology, Boston Children's Hospital, Harvard Medical School, Boston, MA, United States
| | - Douglas B Cowan
- Department of Cardiology, Boston Children's Hospital, Harvard Medical School, Boston, MA, United States
| | - Da-Zhi Wang
- Department of Cardiology, Boston Children's Hospital, Harvard Medical School, Boston, MA, United States
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16
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Interplay between RNA-binding protein HuR and Nox4 as a novel therapeutic target in diabetic kidney disease. Mol Metab 2020; 36:100968. [PMID: 32240965 PMCID: PMC7115155 DOI: 10.1016/j.molmet.2020.02.011] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2019] [Revised: 02/14/2020] [Accepted: 02/22/2020] [Indexed: 12/28/2022] Open
Abstract
Objective Glomerular injury is a prominent pathological feature of diabetic kidney disease (DKD). Constitutively active NADPH oxidase 4 (Nox4) is a major source of reactive oxygen species that mediates hyperglycemia-induced mesangial cell (MC) fibrotic injury. However, the mechanism that Nox4 utilizes to achieve its biological outcome remains elusive, and the signaling pathways that regulate this isoform oxidase are not well understood. Here, our goal is to study the detailed mechanism by which NAPDH oxidase 4 (Nox4) is post-transcriptionally regulated in MC during diabetic pathology. Methods We studied the protein expression of HuR, Nox4 and matrix proteins by western blotting, while we assessed the mRNA stability of Nox4 by RT-PCR and polysomal assay, examined in vitro cultured glomerular mesangial cells treated by high glucose (HG) and diabetic animal induced by STZ. The binding assay between HuR and the Nox4 promoter was done by immuno-precipiating with HuR antibody and detecting the presence of Nox4 mRNA, or by pull-down by using biotinlyated labeled Nox4 promoter RNA and detecting the presence of the HuR protein. The binding was also confirmed in MCs where Nox4 promoter-containing luciferage constructs were transfected. ROS levels were measured with DHE/DCF dyes in cells, or lucigenin chemiluminescence for Nox enzymatic levels, or HPLC assay for superoxide. HuR protein was inhibited by antisense oligo that utilized osmotic pumps for continuous delivery in animal models. The H1bAc1 ratio was measured by an ELISA kit for mice. Results We demonstrate that in MCs, high glucose (HG) elicits a rapid upregulation of Nox4 protein via translational mechanisms. Nox4 mRNA 3′ untranslated region (3′-UTR) contains numerous AU-rich elements (AREs) that are potential binding sites for the RNA-binding protein human antigen R (HuR). We show that HG promotes HuR activation/expression and that HuR is required for HG-induced Nox4 protein expression/mRNA translation, ROS generation, and subsequent MC fibrotic injury. Through a series of invitro RNA-binding assays, we demonstrate that HuR acts via binding to AREs in Nox4 3′-UTR in response to HG. The invivo relevance of these observations is confirmed by the findings that increased Nox4 is accompanied by the binding of HuR to Nox4 mRNA in kidneys from type 1 diabetic animals, and further suppressing HuR expression showed a reno-protective role in a type 1 diabetic mouse model via reducing MC injury, along with the improvement of hyperglycemia and renal function. Conclusions We established for the first time that HuR-mediated translational regulation of Nox4 contributes to the pathogenesis of fibrosis of the glomerular microvascular bed. Thus therapeutic interventions affecting the interplay between Nox4 and HuR could be exploited as valuable tools in designing treatments for DKD. Increased HuR protein activation/expression responding to HG treatment and in diabetic animals. HuR binds to 3′UTR of Nox4 and promotes its translation during HG treatment. An inhibitor for HuR could be a potential treatment for diabetic kidney disease.
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Abstract
The use of RNA electrophoretic mobility shift assays (REMSAs) for analysis of RNA-protein interactions have been limited to lengthy assay time and qualitative assessment. To vastly improve assay efficiency, feasibility and quality of data procured from REMSAs, we combine here some of the best-known labeling and electrophoretic techniques. Nucleic acid fragments are end-labeled with fluorescent tags, as opposed to the radioactive or biotin tags. The fluorescent probes may be detected directly from the electrophoresis gel, eliminating the need for cumbersome membrane transfer and immunoblotting. Modifying the REMSA protocol to include low-molarity, lithium borate conductive media and near-infrared-labeled probes allows for a reduction assay time, quantitative comparison between experimental conditions and crisp band resolution (i.e., optimized results).
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18
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Poganik JR, Long MJC, Disare MT, Liu X, Chang SH, Hla T, Aye Y. Post-transcriptional regulation of Nrf2-mRNA by the mRNA-binding proteins HuR and AUF1. FASEB J 2019; 33:14636-14652. [PMID: 31665914 DOI: 10.1096/fj.201901930r] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The nuclear factor erythroid 2-related factor 2 (Nrf2) signaling axis is a target of covalent drugs and bioactive native electrophiles. However, much of our understanding of Nrf2 regulation has been focused at the protein level. Here we report a post-transcriptional modality to directly regulate Nrf2-mRNA. Our initial studies focused on the effects of the key mRNA-binding protein (mRBP) HuR on global transcriptomic changes incurred upon oxidant or electrophile stimulation. These RNA-sequencing data and subsequent mechanistic analyses led us to discover a novel role of HuR in regulating Nrf2 activity, and in the process, we further identified the related mRBP AUF1 as an additional novel Nrf2 regulator. Both mRBPs regulate Nrf2 activity by direct interaction with the Nrf2 transcript. Our data showed that HuR enhances Nrf2-mRNA maturation and promotes its nuclear export, whereas AUF1 stabilizes Nrf2-mRNA. Both mRBPs target the 3'-UTR of Nrf2-mRNA. Using a Nrf2 activity-reporter zebrafish strain, we document that this post-transcriptional control of Nrf2 activity is conserved at the whole-vertebrate level.-Poganik, J. R., Long, M. J. C., Disare, M. T., Liu, X., Chang, S.-H., Hla, T., Aye, Y. Post-transcriptional regulation of Nrf2-mRNA by the mRNA-binding proteins HuR and AUF1.
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Affiliation(s)
- Jesse R Poganik
- Swiss Federal Institute of Technology Lausanne (EPFL), Lausanne, Switzerland.,Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York, USA
| | - Marcus J C Long
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York, USA
| | - Michael T Disare
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York, USA
| | - Xuyu Liu
- Swiss Federal Institute of Technology Lausanne (EPFL), Lausanne, Switzerland
| | - Sung-Hee Chang
- Department of Medicine, Weill Cornell Medicine, New York, New York, USA
| | - Timothy Hla
- Department of Surgery, Harvard Medical School, Boston, Massachusetts, USA; and.,Vascular Biology Program, Boston Children's Hospital, Boston, Massachusetts, USA
| | - Yimon Aye
- Swiss Federal Institute of Technology Lausanne (EPFL), Lausanne, Switzerland
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19
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Lee JH, Jung M, Hong J, Kim MK, Chung IK. Loss of RNA-binding protein HuR facilitates cellular senescence through posttranscriptional regulation of TIN2 mRNA. Nucleic Acids Res 2019; 46:4271-4285. [PMID: 29584879 PMCID: PMC5934620 DOI: 10.1093/nar/gky223] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Accepted: 03/15/2018] [Indexed: 02/07/2023] Open
Abstract
Cellular senescence can be induced by high levels of reactive oxygen species (ROS) produced by mitochondria. However, the mechanism by which elevated mitochondrial ROS levels are produced during replicative senescence is not yet fully understood. Here, we report that loss of the RNA-binding protein, human antigen R (HuR), during replicative senescence leads to an increase in ROS levels through enhanced mitochondrial localization of the telomeric protein TIN2. HuR binds to the 3′ untranslated region of TIN2 mRNA. This association decreases TIN2 protein levels by both destabilizing TIN2 mRNA and reducing its translation. Conversely, depletion of HuR levels enhances TIN2 expression, leading to increased mitochondrial targeting of TIN2. Mitochondrial localization of TIN2 increases ROS levels, which contributes to induction and maintenance of cellular senescence. Our findings provide compelling evidence for a novel role of HuR in controlling the process of cellular senescence by regulating TIN2-mediated mitochondrial ROS production, and for a useful therapeutic route for modulating intracellular ROS levels in treating both aging-related complications and cancer.
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Affiliation(s)
- Ji Hoon Lee
- Department of Systems Biology, College of Life Science and Biotechnology, Yonsei University, Seoul 03722, Korea
| | - Misun Jung
- Department of Integrated Omics for Biomedical Science, Yonsei University, Seoul 03722, Korea
| | - Juyeong Hong
- Department of Systems Biology, College of Life Science and Biotechnology, Yonsei University, Seoul 03722, Korea
| | - Mi Kyung Kim
- Department of Systems Biology, College of Life Science and Biotechnology, Yonsei University, Seoul 03722, Korea
| | - In Kwon Chung
- Department of Systems Biology, College of Life Science and Biotechnology, Yonsei University, Seoul 03722, Korea.,Department of Integrated Omics for Biomedical Science, Yonsei University, Seoul 03722, Korea
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20
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Soni S, Anand P, Padwad YS. MAPKAPK2: the master regulator of RNA-binding proteins modulates transcript stability and tumor progression. JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH : CR 2019; 38:121. [PMID: 30850014 PMCID: PMC6408796 DOI: 10.1186/s13046-019-1115-1] [Citation(s) in RCA: 71] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Accepted: 02/21/2019] [Indexed: 01/09/2023]
Abstract
The p38 mitogen-activated protein kinase (p38MAPK) pathway has been implicated in a variety of pathological conditions including inflammation and metastasis. Post-transcriptional regulation of genes harboring adenine/uridine-rich elements (AREs) in their 3'-untranslated region (3'-UTR) is controlled by MAPK-activated protein kinase 2 (MAPKAPK2 or MK2), a downstream substrate of the p38MAPK. In response to diverse extracellular stimuli, MK2 influences crucial signaling events, regulates inflammatory cytokines, transcript stability and critical cellular processes. Expression of genes involved in these vital cellular cascades is controlled by subtle interactions in underlying molecular networks and post-transcriptional gene regulation that determines transcript fate in association with RNA-binding proteins (RBPs). Several RBPs associate with the 3'-UTRs of the target transcripts and regulate their expression via modulation of transcript stability. Although MK2 regulates important cellular phenomenon, yet its biological significance in tumor progression has not been well elucidated till date. In this review, we have highlighted in detail the importance of MK2 as the master regulator of RBPs and its role in the regulation of transcript stability, tumor progression, as well as the possibility of use of MK2 as a therapeutic target in tumor management.
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Affiliation(s)
- Sourabh Soni
- Pharmacology and Toxicology Laboratory, Food and Nutraceuticals Division, CSIR-Institute of Himalayan Bioresource Technology (CSIR-IHBT), Palampur, Himachal Pradesh, India.,Academy of Scientific and Innovative Research, Chennai, Tamil Nadu, India
| | - Prince Anand
- Pharmacology and Toxicology Laboratory, Food and Nutraceuticals Division, CSIR-Institute of Himalayan Bioresource Technology (CSIR-IHBT), Palampur, Himachal Pradesh, India.,Academy of Scientific and Innovative Research, Chennai, Tamil Nadu, India
| | - Yogendra S Padwad
- Pharmacology and Toxicology Laboratory, Food and Nutraceuticals Division, CSIR-Institute of Himalayan Bioresource Technology (CSIR-IHBT), Palampur, Himachal Pradesh, India. .,Academy of Scientific and Innovative Research, Chennai, Tamil Nadu, India.
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21
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Evaluation of Post-transcriptional Gene Regulation in Pancreatic Cancer Cells: Studying RNA Binding Proteins and Their mRNA Targets. Methods Mol Biol 2019; 1882:239-252. [PMID: 30378060 DOI: 10.1007/978-1-4939-8879-2_22] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Post-transcriptional regulation of gene expression through interaction between RNA binding proteins (RBPs) and target mRNAs have gained considerable interest over the last decade. Altered expression of RBPs as detected in pancreatic ductal adenocarcinoma (PDAC) cells alters mRNA processing, and in turn, the entire transcriptome and proteome. Thus, this gene regulatory mechanism can regulate important pro-oncogenic signaling pathways (e.g., TP53, WEE1, and c-MYC) in PDAC cells. Ribonucleoprotein immunoprecipitation assays (RNP-IP or RIP) are a modified immunoprecipitation method to study physical interactions between RBPs and their mRNA targets. As a first step to explore RBP interactomes and define novel therapeutic targets and dysregulated pathways in disease, RIPs are a sensitive and established molecular biology technique used to isolate and differentiate bound transcripts to RBPs in a variety of experimental conditions. This chapter describes an up-to-date, detailed protocol for performing this assay in mammalian cytoplasmic extracts (i.e., PDAC cells), and reviews current methods to validate target binding sites such as electrophoretic mobility shift assay (EMSA) and cross-linking immunoprecipitation polymerase chain reaction (CLIP-PCR).
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22
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Astakhova AA, Chistyakov DV, Sergeeva MG, Reiser G. Regulation of the ARE-binding proteins, TTP (tristetraprolin) and HuR (human antigen R), in inflammatory response in astrocytes. Neurochem Int 2018; 118:82-90. [DOI: 10.1016/j.neuint.2018.04.014] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2017] [Revised: 04/20/2018] [Accepted: 04/23/2018] [Indexed: 01/06/2023]
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23
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Habiba U, Kuroshima T, Yanagawa-Matsuda A, Kitamura T, Chowdhury A, Jehung JP, Hossain E, Sano H, Kitagawa Y, Shindoh M, Higashino F. HuR translocation to the cytoplasm of cancer cells in actin-independent manner. Exp Cell Res 2018; 369:218-225. [PMID: 29807023 DOI: 10.1016/j.yexcr.2018.05.021] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Revised: 05/18/2018] [Accepted: 05/21/2018] [Indexed: 11/18/2022]
Abstract
Human antigen R (HuR) is a RNA-binding protein, which binds to the AU-rich element (ARE) in the 3'-untranslated region (3'-UTR) of certain mRNA and is involved in the export and stabilization of ARE-mRNA. HuR constitutively relocates to the cytoplasm in many cancer cells, however the mechanism of intracellular HuR trafficking is poorly understood. To address this question, we examined the functional role of the cytoskeleton in HuR relocalization. We tested the effect of actin depolymerizing macrolide latrunculin A or myosin II ATPase activity inhibitor blebbistatin for HuR relocalization induced by the vasoactive hormone Angiotensin II in cancer and control normal cells. Western blot and confocal imaging data revealed that both inhibitors attenuated the cytoplasmic HuR in normal cells but no such alteration was observed in cancer cells. Concomitant with changes in intracellular HuR localization, both inhibitors markedly decreased the accumulation and half-lives of HuR target ARE-mRNAs in normal cells, whereas no change was observed in cancer cells. Furthermore, co-immunoprecipitation experiments with HuR proteins revealed clear physical interaction with ß-actin only in normal cells. The current study is the first to verify that cancer cells can implicate a microfilament independent HuR transport. We hypothesized that when cytoskeleton structure is impaired, cancer cells can acquire an alternative HuR trafficking strategy.
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Affiliation(s)
- Umma Habiba
- Department of Oral Pathology and Biology, Hokkaido University Faculty of Dental Medicine and Graduate School of Dental Medicine, Sapporo, Japan
| | - Takeshi Kuroshima
- Department of Oral Diagnosis and Medicine, Hokkaido University Faculty of Dental Medicine and Graduate School of Dental Medicine, Sapporo, Japan
| | - Aya Yanagawa-Matsuda
- Department of Oral Pathology and Biology, Hokkaido University Faculty of Dental Medicine and Graduate School of Dental Medicine, Sapporo, Japan
| | - Tetsuya Kitamura
- Department of Oral Pathology and Biology, Hokkaido University Faculty of Dental Medicine and Graduate School of Dental Medicine, Sapporo, Japan
| | - Afma Chowdhury
- Department of Restorative Dentistry, Hokkaido University Faculty of Dental Medicine and Graduate School of Dental Medicine, Sapporo, Japan
| | - Jumond P Jehung
- Department of Restorative Dentistry, Hokkaido University Faculty of Dental Medicine and Graduate School of Dental Medicine, Sapporo, Japan
| | - Elora Hossain
- Department of Molecular Oncology, Hokkaido University Faculty of Dental Medicine and Graduate School of Biomedical Science and Engineering, 060-8586,North 13, West 7, Kita ku, Sapporo, Japan
| | - Hidehiko Sano
- Department of Restorative Dentistry, Hokkaido University Faculty of Dental Medicine and Graduate School of Dental Medicine, Sapporo, Japan
| | - Yoshimasa Kitagawa
- Department of Oral Diagnosis and Medicine, Hokkaido University Faculty of Dental Medicine and Graduate School of Dental Medicine, Sapporo, Japan
| | - Masanobu Shindoh
- Department of Oral Pathology and Biology, Hokkaido University Faculty of Dental Medicine and Graduate School of Dental Medicine, Sapporo, Japan
| | - Fumihiro Higashino
- Department of Oral Pathology and Biology, Hokkaido University Faculty of Dental Medicine and Graduate School of Dental Medicine, Sapporo, Japan; Department of Molecular Oncology, Hokkaido University Faculty of Dental Medicine and Graduate School of Biomedical Science and Engineering, 060-8586,North 13, West 7, Kita ku, Sapporo, Japan.
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24
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Clinical Significance and Biological Role of HuR in Head and Neck Carcinomas. DISEASE MARKERS 2018; 2018:4020937. [PMID: 29619127 PMCID: PMC5829322 DOI: 10.1155/2018/4020937] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Accepted: 11/27/2017] [Indexed: 12/17/2022]
Abstract
Background Hu-antigen R (HuR) is a posttranscriptional regulator of several target mRNAs, implicated in carcinogenesis. This review aims to present the current evidence regarding the biological role and potential clinical significance of HuR in head and neck carcinomas. Methods The existing literature concerning HuR expression and function in head and neck carcinomas is critically presented and summarised. Results HuR is expressed in the majority of the examined samples, showing higher cytoplasmic levels in malignant or premalignant cases. Moreover, HuR modulates several genes implicated in biological processes important for malignant transformation, growth, and invasiveness. HuR seems to be an adverse prognosticator in patients with OSCCs, whereas a correlation with a more aggressive phenotype is reported in several types of carcinomas. Conclusions A consistent role of HuR in the carcinogenesis and progression of head and neck carcinomas is suggested; nevertheless, further studies are warranted to expand the present information.
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25
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Liu Y, Chen X, Cheng R, Yang F, Yu M, Wang C, Cui S, Hong Y, Liang H, Liu M, Zhao C, Ding M, Sun W, Liu Z, Sun F, Zhang C, Zhou Z, Jiang X, Chen X. The Jun/miR-22/HuR regulatory axis contributes to tumourigenesis in colorectal cancer. Mol Cancer 2018; 17:11. [PMID: 29351796 PMCID: PMC5775639 DOI: 10.1186/s12943-017-0751-3] [Citation(s) in RCA: 92] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Accepted: 12/26/2017] [Indexed: 12/11/2022] Open
Abstract
Background Colorectal cancer (CRC) is a severe health problem worldwide. Clarifying the mechanisms for the deregulation of oncogenes and tumour suppressors in CRC is vital for its diagnosis, treatment, prognosis and prevention. Hu antigen R (HuR), which is highly upregulated in CRC, functions as a pivotal oncogene to promote CRC progression. However, the underlying cause of its dysregulation is poorly understood. Methods In CRC tissue sample pairs, HuR protein levels were measured by Western blot and immunohistochemical (IHC) staining, respectively. HuR mRNA levels were also monitored by qRT-PCR. Combining meta-analysis and microRNA (miRNA) target prediction software, we predicted miRNAs that targeted HuR. Pull-down assay, Western blot and luciferase assay were utilized to demonstrate the direct binding of miR-22 on HuR’s 3’-UTR. The biological effects of HuR and miR-22 were investigated both in vitro by CCK-8, EdU and Transwell assays and in vivo by a xenograft mice model. JASPAR and SABiosciences were used to predict transcriptional factors that could affect miR-22. Luciferase assay was used to explore the validity of putative Jun binding sites for miR-22 regulation. ChIP assay was performed to test the Jun’s occupancy on the C17orf91 promoter. Results We observed a significant upregulation of HuR in CRC tissue pairs and confirmed the oncogenic function of HuR both in vitro and in vivo. We found that an important tumour-suppressive miRNA, miR-22, was significantly downregulated in CRC tissues and inversely correlated with HuR in both CRC tissues and CRC cell lines. We demonstrated that miR-22 directly bound to the 3’-UTR of HuR and led to inhibition of HuR protein, which repressed CRC proliferation and migration in vitro and decelerated CRC xenografted tumour growth in vivo. Furthermore, we found that the onco-transcription factor Jun could inhibit the transcription of miR-22. Conclusions Our findings highlight the critical roles of the Jun/miR-22/HuR regulatory axis in CRC progression and may provide attractive potential targets for CRC prevention and treatment. Electronic supplementary material The online version of this article (10.1186/s12943-017-0751-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Yanqing Liu
- State Key Laboratory of Pharmaceutical Biotechnology, Collaborative Innovation Center of Chemistry for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, NJU Advanced Institute for Life Sciences (NAILS), School of Life Sciences, Nanjing University, Nanjing, Jiangsu, 210046, China
| | - Xiaorui Chen
- State Key Laboratory of Pharmaceutical Biotechnology, Collaborative Innovation Center of Chemistry for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, NJU Advanced Institute for Life Sciences (NAILS), School of Life Sciences, Nanjing University, Nanjing, Jiangsu, 210046, China
| | - Rongjie Cheng
- State Key Laboratory of Pharmaceutical Biotechnology, Collaborative Innovation Center of Chemistry for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, NJU Advanced Institute for Life Sciences (NAILS), School of Life Sciences, Nanjing University, Nanjing, Jiangsu, 210046, China
| | - Fei Yang
- State Key Laboratory of Pharmaceutical Biotechnology, Collaborative Innovation Center of Chemistry for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, NJU Advanced Institute for Life Sciences (NAILS), School of Life Sciences, Nanjing University, Nanjing, Jiangsu, 210046, China
| | - Mengchao Yu
- State Key Laboratory of Pharmaceutical Biotechnology, Collaborative Innovation Center of Chemistry for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, NJU Advanced Institute for Life Sciences (NAILS), School of Life Sciences, Nanjing University, Nanjing, Jiangsu, 210046, China
| | - Chen Wang
- State Key Laboratory of Pharmaceutical Biotechnology, Collaborative Innovation Center of Chemistry for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, NJU Advanced Institute for Life Sciences (NAILS), School of Life Sciences, Nanjing University, Nanjing, Jiangsu, 210046, China
| | - Shufang Cui
- State Key Laboratory of Pharmaceutical Biotechnology, Collaborative Innovation Center of Chemistry for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, NJU Advanced Institute for Life Sciences (NAILS), School of Life Sciences, Nanjing University, Nanjing, Jiangsu, 210046, China
| | - Yeting Hong
- State Key Laboratory of Pharmaceutical Biotechnology, Collaborative Innovation Center of Chemistry for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, NJU Advanced Institute for Life Sciences (NAILS), School of Life Sciences, Nanjing University, Nanjing, Jiangsu, 210046, China
| | - Hongwei Liang
- State Key Laboratory of Pharmaceutical Biotechnology, Collaborative Innovation Center of Chemistry for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, NJU Advanced Institute for Life Sciences (NAILS), School of Life Sciences, Nanjing University, Nanjing, Jiangsu, 210046, China
| | - Minghui Liu
- State Key Laboratory of Pharmaceutical Biotechnology, Collaborative Innovation Center of Chemistry for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, NJU Advanced Institute for Life Sciences (NAILS), School of Life Sciences, Nanjing University, Nanjing, Jiangsu, 210046, China
| | - Chihao Zhao
- State Key Laboratory of Pharmaceutical Biotechnology, Collaborative Innovation Center of Chemistry for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, NJU Advanced Institute for Life Sciences (NAILS), School of Life Sciences, Nanjing University, Nanjing, Jiangsu, 210046, China
| | - Meng Ding
- State Key Laboratory of Pharmaceutical Biotechnology, Collaborative Innovation Center of Chemistry for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, NJU Advanced Institute for Life Sciences (NAILS), School of Life Sciences, Nanjing University, Nanjing, Jiangsu, 210046, China
| | - Wu Sun
- Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center of Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin, 300060, China
| | - Zhijian Liu
- Department of Gastrointestinal Surgery, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, Jiangsu, 210008, China
| | - Feng Sun
- Department of Gastrointestinal Surgery, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, Jiangsu, 210008, China
| | - Chenyu Zhang
- State Key Laboratory of Pharmaceutical Biotechnology, Collaborative Innovation Center of Chemistry for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, NJU Advanced Institute for Life Sciences (NAILS), School of Life Sciences, Nanjing University, Nanjing, Jiangsu, 210046, China
| | - Zhen Zhou
- State Key Laboratory of Pharmaceutical Biotechnology, Collaborative Innovation Center of Chemistry for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, NJU Advanced Institute for Life Sciences (NAILS), School of Life Sciences, Nanjing University, Nanjing, Jiangsu, 210046, China.
| | - Xiaohong Jiang
- State Key Laboratory of Pharmaceutical Biotechnology, Collaborative Innovation Center of Chemistry for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, NJU Advanced Institute for Life Sciences (NAILS), School of Life Sciences, Nanjing University, Nanjing, Jiangsu, 210046, China.
| | - Xi Chen
- State Key Laboratory of Pharmaceutical Biotechnology, Collaborative Innovation Center of Chemistry for Life Sciences, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, NJU Advanced Institute for Life Sciences (NAILS), School of Life Sciences, Nanjing University, Nanjing, Jiangsu, 210046, China.
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Ezegbunam W, Foronjy R. Posttranscriptional control of airway inflammation. WILEY INTERDISCIPLINARY REVIEWS-RNA 2017; 9. [PMID: 29071794 DOI: 10.1002/wrna.1455] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Revised: 09/07/2017] [Accepted: 09/08/2017] [Indexed: 12/18/2022]
Abstract
Acute inflammation in the lungs is a vital protective response, efficiently and swiftly eliminating inciters of tissue injury. However, in respiratory diseases characterized by chronic inflammation, such as chronic obstructive pulmonary disease and asthma, enhanced expression of inflammatory mediators leads to tissue damage and impaired lung function. Although transcription is an essential first step in the induction of proinflammatory genes, tight regulation of inflammation requires more rapid, flexible responses. Increasing evidence shows that such responses are achieved by posttranscriptional mechanisms directly affecting mRNA stability and translation initiation. RNA-binding proteins, microRNAs, and long noncoding RNAs interact with messenger RNA and each other to impact the stability and/or translation of mRNAs implicated in lung inflammation. Recent research has shown that these biological processes play a central role in the pathogenesis of several important pulmonary conditions. This review will highlight several posttranscriptional control mechanisms that influence lung inflammation and the known associations of derangements in these mechanisms with common respiratory diseases. WIREs RNA 2018, 9:e1455. doi: 10.1002/wrna.1455 This article is categorized under: RNA in Disease and Development > RNA in Disease RNA Structure and Dynamics > Influence of RNA Structure in Biological Systems RNA Interactions with Proteins and Other Molecules > Protein-RNA Interactions: Functional Implications RNA Turnover and Surveillance > Regulation of RNA Stability.
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Affiliation(s)
- Wendy Ezegbunam
- Division of Pulmonary and Critical Care Medicine, Department of Medicine and Cell Biology, SUNY Downstate Medical Center, Brooklyn, NY, USA
| | - Robert Foronjy
- Division of Pulmonary and Critical Care Medicine, Department of Medicine and Cell Biology, SUNY Downstate Medical Center, Brooklyn, NY, USA
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García-Mauriño SM, Rivero-Rodríguez F, Velázquez-Cruz A, Hernández-Vellisca M, Díaz-Quintana A, De la Rosa MA, Díaz-Moreno I. RNA Binding Protein Regulation and Cross-Talk in the Control of AU-rich mRNA Fate. Front Mol Biosci 2017; 4:71. [PMID: 29109951 PMCID: PMC5660096 DOI: 10.3389/fmolb.2017.00071] [Citation(s) in RCA: 105] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Accepted: 10/04/2017] [Indexed: 02/06/2023] Open
Abstract
mRNA metabolism is tightly orchestrated by highly-regulated RNA Binding Proteins (RBPs) that determine mRNA fate, thereby influencing multiple cellular functions across biological contexts. Here, we review the interplay between six well-known RBPs (TTP, AUF-1, KSRP, HuR, TIA-1, and TIAR) that recognize AU-rich elements (AREs) at the 3' untranslated regions of mRNAs, namely ARE-RBPs. Examples of the links between their cross-regulations and modulation of their targets are analyzed during mRNA processing, turnover, localization, and translational control. Furthermore, ARE recognition can be self-regulated by several factors that lead to the prevalence of one RBP over another. Consequently, we examine the factors that modulate the dynamics of those protein-RNA transient interactions to better understand the final consequences of the regulation mediated by ARE-RBPs. For instance, factors controlling the RBP isoforms, their conformational state or their post-translational modifications (PTMs) can strongly determine the fate of the protein-RNA complexes. Moreover, mRNA specific sequence and secondary structure or subtle environmental changes are also key determinants to take into account. To sum up, the whole understanding of such a fine tuned regulation is a challenge for future research and requires the integration of all the available structural and functional data by in vivo, in vitro and in silico approaches.
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Affiliation(s)
| | | | | | | | | | | | - Irene Díaz-Moreno
- Instituto de Investigaciones Químicas, Centro de Investigaciones Científicas Isla de la Cartuja, Universidad de Sevilla, Consejo Superior de Investigaciones Científicas, Seville, Spain
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28
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Chen PI, Cao A, Miyagawa K, Tojais NF, Hennigs JK, Li CG, Sweeney NM, Inglis AS, Wang L, Li D, Ye M, Feldman BJ, Rabinovitch M. Amphetamines promote mitochondrial dysfunction and DNA damage in pulmonary hypertension. JCI Insight 2017; 2:e90427. [PMID: 28138562 DOI: 10.1172/jci.insight.90427] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Amphetamine (AMPH) or methamphetamine (METH) abuse can cause oxidative damage and is a risk factor for diseases including pulmonary arterial hypertension (PAH). Pulmonary artery endothelial cells (PAECs) from AMPH-associated-PAH patients show DNA damage as judged by γH2AX foci and DNA comet tails. We therefore hypothesized that AMPH induces DNA damage and vascular pathology by interfering with normal adaptation to an environmental perturbation causing oxidative stress. Consistent with this, we found that AMPH alone does not cause DNA damage in normoxic PAECs, but greatly amplifies DNA damage in hypoxic PAECs. The mechanism involves AMPH activation of protein phosphatase 2A, which potentiates inhibition of Akt. This increases sirtuin 1, causing deacetylation and degradation of HIF1α, thereby impairing its transcriptional activity, resulting in a reduction in pyruvate dehydrogenase kinase 1 and impaired cytochrome c oxidase 4 isoform switch. Mitochondrial oxidative phosphorylation is inappropriately enhanced and, as a result of impaired electron transport and mitochondrial ROS increase, caspase-3 is activated and DNA damage is induced. In mice given binge doses of METH followed by hypoxia, HIF1α is suppressed and pulmonary artery DNA damage foci are associated with worse pulmonary vascular remodeling. Thus, chronic AMPH/METH can induce DNA damage associated with vascular disease by subverting the adaptive responses to oxidative stress.
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29
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Rogers S, de Souza AR, Zago M, Iu M, Guerrina N, Gomez A, Matthews J, Baglole CJ. Aryl hydrocarbon receptor (AhR)-dependent regulation of pulmonary miRNA by chronic cigarette smoke exposure. Sci Rep 2017; 7:40539. [PMID: 28079158 PMCID: PMC5227990 DOI: 10.1038/srep40539] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Accepted: 12/07/2016] [Indexed: 01/04/2023] Open
Abstract
The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor historically known for its toxic responses to man-made pollutants such as dioxin. More recently, the AhR has emerged as a suppressor of inflammation, oxidative stress and apoptosis from cigarette smoke by mechanisms that may involve the regulation of microRNA. However, little is known about the AhR regulation of miRNA expression in the lung in response to inhaled toxicants. Therefore, we exposed Ahr−/− and Ahr+/− mice to cigarette smoke for 4 weeks and evaluated lung miRNA expression by PCR array. There was a dramatic regulation of lung miRNA by the AhR in the absence of exogenous ligand. In response to cigarette smoke, there were more up-regulated miRNA in Ahr−/− mice compared to Ahr+/− mice, including the cancer-associated miRNA miR-96. There was no significant change in the expression of the AhR regulated proteins HuR and cyclooxygenase-2 (COX-2). There were significant increases in the anti-oxidant gene sulfiredoxin 1 (Srxn1) and FOXO3a- predicted targets of miR-96. Collectively, these data support a prominent role for the AhR in regulating lung miRNA expression. Further studies to elucidate a role for these miRNA may further uncover novel biological function for the AhR in respiratory health and disease.
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Affiliation(s)
- Sarah Rogers
- Departments of Medicine, McGill University, Montreal, Quebec, Canada
| | - Angela Rico de Souza
- Research Institute of the McGill University Health Centre (RI-MUHC), Meakins-Christie Laboratories, Montreal, QC, Canada
| | - Michela Zago
- Departments of Pharmacology &Therapeutics, McGill University, Montreal, Quebec, Canada
| | - Matthew Iu
- Departments of Medicine, McGill University, Montreal, Quebec, Canada
| | - Necola Guerrina
- Departments of Pathology, McGill University, Montreal, Quebec, Canada
| | - Alvin Gomez
- Department of Pharmacology &Toxicology, University of Toronto, Toronto, Ontario, Canada
| | - Jason Matthews
- Department of Pharmacology &Toxicology, University of Toronto, Toronto, Ontario, Canada.,Department of Nutrition, University of Oslo, Oslo, Norway
| | - Carolyn J Baglole
- Departments of Medicine, McGill University, Montreal, Quebec, Canada.,Research Institute of the McGill University Health Centre (RI-MUHC), Meakins-Christie Laboratories, Montreal, QC, Canada.,Departments of Pharmacology &Therapeutics, McGill University, Montreal, Quebec, Canada.,Departments of Pathology, McGill University, Montreal, Quebec, Canada
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30
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Kotta-Loizou I, Vasilopoulos SN, Coutts RHA, Theocharis S. Current Evidence and Future Perspectives on HuR and Breast Cancer Development, Prognosis, and Treatment. Neoplasia 2016; 18:674-688. [PMID: 27764700 PMCID: PMC5071540 DOI: 10.1016/j.neo.2016.09.002] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Revised: 09/14/2016] [Accepted: 09/19/2016] [Indexed: 12/20/2022] Open
Abstract
Hu-antigen R (HuR) is an RNA-binding posttranscriptional regulator that belongs to the Hu/ELAV family. HuR expression levels are modulated by a variety of proteins, microRNAs, chemical compounds, or the microenvironment, and in turn, HuR affects mRNA stability and translation of various genes implicated in breast cancer formation, progression, metastasis, and treatment. The aim of the present review is to critically summarize the role of HuR in breast cancer development and its potential as a prognosticator and a therapeutic target. In this aspect, all the existing English literature concerning HuR expression and function in breast cancer cell lines, in vivo animal models, and clinical studies is critically presented and summarized. HuR modulates many genes implicated in biological processes crucial for breast cancer formation, growth, and metastasis, whereas the link between HuR and these processes has been demonstrated directly in vitro and in vivo. Additionally, clinical studies reveal that HuR is associated with more aggressive forms of breast cancer and is a putative prognosticator for patients' survival. All the above indicate HuR as a promising drug target for cancer therapy; nevertheless, additional studies are required to fully understand its potential and determine against which types of breast cancer and at which stage of the disease a therapeutic agent targeting HuR would be more effective.
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Affiliation(s)
- Ioly Kotta-Loizou
- Department of Life Sciences, Faculty of Natural Sciences, Imperial College London, London SW7 2AZ, United Kingdom; First Department of Pathology, Medical School, National and Kapodistrian University of Athens, Athens 11527, Greece.
| | - Spyridon N Vasilopoulos
- First Department of Pathology, Medical School, National and Kapodistrian University of Athens, Athens 11527, Greece
| | - Robert H A Coutts
- Geography, Environment and Agriculture Division, Department of Biological and Environmental Sciences, School of Life and Medical Sciences, University of Hertfordshire, Hatfield AL10 9AB, United Kingdom
| | - Stamatios Theocharis
- First Department of Pathology, Medical School, National and Kapodistrian University of Athens, Athens 11527, Greece
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Bose S, Tholanikunnel TE, Reuben A, Tholanikunnel BG, Spicer EK. Regulation of nucleolin expression by miR-194, miR-206, and HuR. Mol Cell Biochem 2016; 417:141-53. [PMID: 27221739 DOI: 10.1007/s11010-016-2721-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Accepted: 05/13/2016] [Indexed: 11/29/2022]
Abstract
Nucleolin is a proliferation-associated protein that is overexpressed in multiple types of cancer. The mechanisms leading to overexpression of nucleolin in specific cancers are not fully understood. This study found that nucleolin is notably elevated in breast cancer cell lines MCF-7 and MDA-231 compared to nonmalignant breast epithelial MCF-10A cells. In silico analyses revealed the presence of putative binding sites for microRNAs miR-194 and miR-206 in the 3'-untranslated region (3'-UTR) of Ncl mRNA. Transfection of the three cell lines with pre-miR-194 or pre-miR-206 specifically decreased the Ncl mRNA and protein expression. Treatments of the cells with antagomiR-194 or antagomiR-206 upregulated nucleolin expression ~2- to 3-fold. Co-transfection of cells with a reporter vector containing the Ncl 3'-UTR downstream from the Renilla luciferase gene and pre-miR-194 or pre-miR-206 led to a ~3-fold decrease in Renilla/firefly luciferase activity. Cytoplasmic levels of the RNA-binding protein HuR were higher in MCF-7 and MDA-231 cells than those in MCF-10A cells. RNA immunoprecipitation assays demonstrated that HuR binds to Ncl mRNA in all the three cell types. ShRNA-mediated knock-down of HuR induced a decrease in nucleolin expression, while exogenous expression of HuR led to upregulation of nucleolin expression. Analysis of the polysome-monosome distribution of Ncl mRNA in HuR knock-down cells demonstrated that HuR enhances the translation efficiency of Ncl mRNA. These findings demonstrate that nucleolin expression is down-regulated by miR-194 and miR-206 and upregulated by HuR.
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Affiliation(s)
- Sudeep Bose
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, P. O. Box 250509, Charleston, SC, 29425, USA
- Amity Centre for Medical Biotechnology, Amity Institute of Biotechnology, Amity University, Gautam Buddha Nagar Sec-125, Noida, 201301, India
| | - Tracy E Tholanikunnel
- College of Medicine, Medical University of South Carolina, Charleston, SC, 29425, USA
| | - Adrian Reuben
- Division of Gastroenterology and Hepatology, Department of Medicine, Medical University of South Carolina, Charleston, SC, 29425, USA
| | - Baby G Tholanikunnel
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, P. O. Box 250509, Charleston, SC, 29425, USA.
| | - Eleanor K Spicer
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, P. O. Box 250509, Charleston, SC, 29425, USA
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Regulation of Stem Cell Self-Renewal and Oncogenesis by RNA-Binding Proteins. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 907:153-88. [PMID: 27256386 DOI: 10.1007/978-3-319-29073-7_7] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Throughout their life span, multicellular organisms rely on stem cell systems. During development pluripotent embryonic stem cells give rise to all cell types that make up the organism. After birth, tissue stem cells maintain properly functioning tissues and organs under homeostasis as well as promote regeneration after tissue damage or injury. Stem cells are capable of self-renewal, which is the ability to divide indefinitely while retaining the potential of differentiation into multiple cell types. The ability to self-renew, however, is a double-edged sword; the molecular mechanisms of self-renewal can be a target of malignant transformation driving tumor development and progression. Growing lines of evidence have shown that RNA-binding proteins (RBPs) play pivotal roles in the regulation of self-renewal by modulating metabolism of coding and non-coding RNAs both in normal tissues and in cancers. In this review, we discuss our current understanding of tissue stem cell systems and how RBPs regulate stem cell fates as well as how the regulatory functions of RBPs contribute to oncogenesis.
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33
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Shi J, He Y, Hewett SJ, Hewett JA. Interleukin 1β Regulation of the System xc- Substrate-specific Subunit, xCT, in Primary Mouse Astrocytes Involves the RNA-binding Protein HuR. J Biol Chem 2015; 291:1643-1651. [PMID: 26601945 DOI: 10.1074/jbc.m115.697821] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2015] [Indexed: 01/05/2023] Open
Abstract
System xc(-) is a heteromeric amino acid cystine/glutamate antiporter that is constitutively expressed by cells of the CNS, where it functions in the maintenance of intracellular glutathione and extracellular glutamate levels. We recently determined that the cytokine, IL-1β, increases the activity of system xc(-) in CNS astrocytes secondary to an up-regulation of its substrate-specific light chain, xCT, and that this occurs, in part, at the level of transcription. However, an in silico analysis of the murine xCT 3'-UTR identified numerous copies of adenine- and uridine-rich elements, raising the possibility that undefined trans-acting factors governing mRNA stability and translation may also contribute to xCT expression. Here we show that IL-1β increases the level of mRNA encoding xCT in primary cultures of astrocytes isolated from mouse cortex in association with an increase in xCT mRNA half-life. Additionally, IL-1β induces HuR translocation from the nucleus to the cytoplasm. RNA immunoprecipitation analysis reveals that HuR binds directly to the 3'-UTR of xCT in an IL-1β-dependent manner. Knockdown of endogenous HuR protein abrogates the IL-1β-mediated increase in xCT mRNA half-life, whereas overexpression of HuR in unstimulated primary mouse astrocytes doubles the half-life of constitutive xCT mRNA. This latter effect is accompanied by an increase in xCT protein levels, as well as a functional increase in system xc(-) activity. Altogether, these data support a critical role for HuR in mediating the IL-1β-induced stabilization of astrocyte xCT mRNA.
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Affiliation(s)
- Jingxue Shi
- From the Department of Biology and Program in Neuroscience, Syracuse University, Syracuse, New York 13244
| | - Yan He
- From the Department of Biology and Program in Neuroscience, Syracuse University, Syracuse, New York 13244
| | - Sandra J Hewett
- From the Department of Biology and Program in Neuroscience, Syracuse University, Syracuse, New York 13244
| | - James A Hewett
- From the Department of Biology and Program in Neuroscience, Syracuse University, Syracuse, New York 13244.
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Yin H, Sun Y, Wang X, Park J, Zhang Y, Li M, Yin J, Liu Q, Wei M. Progress on the relationship between miR-125 family and tumorigenesis. Exp Cell Res 2015; 339:252-60. [PMID: 26407906 DOI: 10.1016/j.yexcr.2015.09.015] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Revised: 08/25/2015] [Accepted: 09/19/2015] [Indexed: 12/21/2022]
Abstract
miRNA-125 family, which is a highly conserved miRNA family throughout evolution, is consist of miRNA-125a-3p, miRNA-125a-5p, miRNA-125b-1 and miRNA-125b-2.The aberrant expression of miR-125 familyis tightly related to tumorigenesis and tumor development. The downstream targets of miRNA-125 include transcription factors like STAT3, cytokines like IL-6 and TGF-β, tumor suppressing protein p53, pro-apoptotic protein Bak1 and RNA binding protein HuR et al. Through regulating these downstream targets miR-125 family is involved in regulating tumorigenesis and tumor development. Nowadays, miR-125b have already became a putative and valuable biomarker for cancer diagnosis, treatment and prognosis. In this review, we mainly summarize the dual function of miRNA-125 family in suppression and promotion of cancer cells and further elaborate its regulatory mechanisms from four facets, proliferation, apoptosis, invasion or metastasis and immune response.
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Affiliation(s)
- Hang Yin
- Dalian 24 High School, Dalian 116023, China
| | - Yuqiang Sun
- Department of Neurosurgery, The Second Afiliated Hospital of Dalian Medical University, Dalian 116023, China
| | - Xiaofeng Wang
- Department of Neurosurgery, The Second Afiliated Hospital of Dalian Medical University, Dalian 116023, China
| | - Jeiyoun Park
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06520, USA
| | - Yuanyang Zhang
- Department of Ultrasonography, Mudanjiang Medical University, Mudanjiang, Heilongjiang 157011, China
| | - Molin Li
- Department of Pathophysiology, Dalian Medical University, Dalian 116044, China
| | - Jian Yin
- Department of Neurosurgery, The Second Afiliated Hospital of Dalian Medical University, Dalian 116023, China
| | - Qiang Liu
- Institute of Cancer Stem Cell, Dalian Medical University, Dalian, China
| | - Minghai Wei
- Department of Neurosurgery, The Second Afiliated Hospital of Dalian Medical University, Dalian 116023, China.
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35
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Newman R, McHugh J, Turner M. RNA binding proteins as regulators of immune cell biology. Clin Exp Immunol 2015. [PMID: 26201441 DOI: 10.1111/cei.12684] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Sequence-specific RNA binding proteins (RBP) are important regulators of the immune response. RBP modulate gene expression by regulating splicing, polyadenylation, localization, translation and decay of target mRNAs. Increasing evidence suggests that RBP play critical roles in the development, activation and function of lymphocyte populations in the immune system. This review will discuss the post-transcriptional regulation of gene expression by RBP during lymphocyte development, with particular focus on the Tristetraprolin family of RBP.
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Affiliation(s)
- R Newman
- Babraham Institute, Cambridge, UK
| | - J McHugh
- Babraham Institute, Cambridge, UK
| | - M Turner
- Babraham Institute, Cambridge, UK
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36
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Lamy S, Ben Saad A, Zgheib A, Annabi B. Olive oil compounds inhibit the paracrine regulation of TNF-α-induced endothelial cell migration through reduced glioblastoma cell cyclooxygenase-2 expression. J Nutr Biochem 2015; 27:136-45. [PMID: 26410343 DOI: 10.1016/j.jnutbio.2015.08.026] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2015] [Revised: 08/19/2015] [Accepted: 08/21/2015] [Indexed: 11/25/2022]
Abstract
The established causal relationship between the chronic inflammatory microenvironment, tumor development and cancer recurrence has provided leads for developing novel preventive strategies. Accumulating experimental, clinical and epidemiological data has provided support for the chemopreventive properties of olive oil compounds traditionally found within the Mediterranean diet. In this study, we investigated whether tyrosol (Tyr), hydroxytyrosol, oleuropein and oleic acid (OA), four compounds contained in extra virgin olive oil, can prevent tumor necrosis factor (TNF)-α-induced expression of cyclooxygenase (COX)-2 (an inflammation biomarker) in a human glioblastoma cell (U-87 MG) model. We found that Tyr and OA significantly inhibited TNF-α-induced COX-2 gene and protein expression, as well as PGE2 secretion. Both compounds also inhibited TNF-α-induced JNK and ERK phosphorylation, whereas only Tyr inhibited TNF-α-induced NF-κB phosphorylation. Paracrine-regulated migration of human brain microvascular endothelial cells (HBMECs) was assessed using growth factor-enriched conditioned media (CM) isolated from U-87 MG cells. We found that while PGE2 triggered HBMEC migration, the CM isolated from U-87 MG cells, where either COX-2 or NF-κB had been silenced or had been treated with Tyr or OA, exhibited decreased chemotactic properties. These observations demonstrate that olive oil compounds inhibit the effect of the chronic inflammatory microenvironment on glioblastoma progression through TNF-α actions and may be useful in cancer chemoprevention.
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Affiliation(s)
- Sylvie Lamy
- Laboratoire d'Oncologie Moléculaire, Centre de Recherche BioMed, Université du Québec à Montréal, C.P. 8888, Succ. Centre-ville, Montréal, QC, Canada H3C 3P8.
| | - Aroua Ben Saad
- Laboratoire d'Oncologie Moléculaire, Centre de Recherche BioMed, Université du Québec à Montréal, C.P. 8888, Succ. Centre-ville, Montréal, QC, Canada H3C 3P8.
| | - Alain Zgheib
- Laboratoire d'Oncologie Moléculaire, Centre de Recherche BioMed, Université du Québec à Montréal, C.P. 8888, Succ. Centre-ville, Montréal, QC, Canada H3C 3P8.
| | - Borhane Annabi
- Laboratoire d'Oncologie Moléculaire, Centre de Recherche BioMed, Université du Québec à Montréal, C.P. 8888, Succ. Centre-ville, Montréal, QC, Canada H3C 3P8.
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Doller A, Badawi A, Schmid T, Brauss T, Pleli T, zu Heringdorf DM, Piiper A, Pfeilschifter J, Eberhardt W. The cytoskeletal inhibitors latrunculin A and blebbistatin exert antitumorigenic properties in human hepatocellular carcinoma cells by interfering with intracellular HuR trafficking. Exp Cell Res 2014; 330:66-80. [PMID: 25240929 DOI: 10.1016/j.yexcr.2014.09.010] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2014] [Revised: 09/01/2014] [Accepted: 09/07/2014] [Indexed: 10/24/2022]
Abstract
The impact of the RNA-binding protein HuR for the post-transcriptional deregulation of tumor-relevant genes is well established. Despite of elevations in HuR expression levels, an increase in cytoplasmic HuR abundance in many cases correlates with a high grade of malignancy. Here, we demonstrated that administration of the actin-depolymerizing macrolide latrunculin A, or blebbistatin, an inhibitor of myosin II ATPase activity, caused a dose- and time-dependent reduction in the high cytoplasmic HuR content of HepG2 and Huh7 hepatocellular carcinoma (HCC) cells. Subcellular fractionation revealed that in addition, both inhibitors strongly attenuated cytoskeletal and membrane-bound HuR abundance and conversely increased the HuR amount in nuclear cell fractions. Concomitant with changes in intracellular HuR localization, both cytoskeletal inhibitors markedly decreased the half-lives of cyclooxygenase-2 (COX-2), cyclin A and cyclin D1 encoding mRNAs resulting in a significant reduction in their expression levels in HepG2 cells. Importantly, a similar reduction in the expression of these HuR targets was achieved by a RNA interference (RNAi)-mediated knockdown of either HuR or nonmuscle myoin IIA. Using polysomal fractionation, we further demonstrate that the decrease in cytoplasmic HuR by latrunculin A or blebbistatin is accompanied by a marked change in the allocation of HuR and its mRNA cargo from polysomes to ribonucleoprotein (RNP) particles. Functionally, the basal migration and prostaglandin E2 synthesis are similarly impaired in inhibitor-treated and stable HuR-knockdown HepG2 cells. Our data demonstrate that interfering with the actomyosin-dependent HuR trafficking may comprise a valid therapeutic option for antagonizing pathologic posttranscriptional gene expression by HuR and furthermore emphasize the potential benefit of HuR inhibitory strategies for treatment of HCC.
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Affiliation(s)
- Anke Doller
- Pharmazentrum Frankfurt/ZAFES, Klinikum der Goethe-Universität Frankfurt, Frankfurt/Main, Germany
| | - Amel Badawi
- Pharmazentrum Frankfurt/ZAFES, Klinikum der Goethe-Universität Frankfurt, Frankfurt/Main, Germany
| | - Tobias Schmid
- Institut für Biochemie I (Pathobiochemie), Klinikum der Goethe-Universität Frankfurt, Frankfurt/Main, Germany
| | - Thilo Brauss
- Institut für Biochemie I (Pathobiochemie), Klinikum der Goethe-Universität Frankfurt, Frankfurt/Main, Germany
| | - Thomas Pleli
- Medizinische Klinik 1, Schwerpunkt Gastroenterologie und Hepatologie, Klinikum der Goethe-Universität Frankfurt, Frankfurt/Main, Germany
| | | | - Albrecht Piiper
- Medizinische Klinik 1, Schwerpunkt Gastroenterologie und Hepatologie, Klinikum der Goethe-Universität Frankfurt, Frankfurt/Main, Germany
| | - Josef Pfeilschifter
- Pharmazentrum Frankfurt/ZAFES, Klinikum der Goethe-Universität Frankfurt, Frankfurt/Main, Germany
| | - Wolfgang Eberhardt
- Pharmazentrum Frankfurt/ZAFES, Klinikum der Goethe-Universität Frankfurt, Frankfurt/Main, Germany.
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McCarty MF. AMPK activation--protean potential for boosting healthspan. AGE (DORDRECHT, NETHERLANDS) 2014; 36:641-663. [PMID: 24248330 PMCID: PMC4039279 DOI: 10.1007/s11357-013-9595-y] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2013] [Accepted: 10/22/2013] [Indexed: 06/01/2023]
Abstract
AMP-activated kinase (AMPK) is activated when the cellular (AMP+ADP)/ATP ratio rises; it therefore serves as a detector of cellular "fuel deficiency." AMPK activation is suspected to mediate some of the health-protective effects of long-term calorie restriction. Several drugs and nutraceuticals which slightly and safely impede the efficiency of mitochondrial ATP generation-most notably metformin and berberine-can be employed as clinical AMPK activators and, hence, may have potential as calorie restriction mimetics for extending healthspan. Indeed, current evidence indicates that AMPK activators may reduce risk for atherosclerosis, heart attack, and stroke; help to prevent ventricular hypertrophy and manage congestive failure; ameliorate metabolic syndrome, reduce risk for type 2 diabetes, and aid glycemic control in diabetics; reduce risk for weight gain; decrease risk for a number of common cancers while improving prognosis in cancer therapy; decrease risk for dementia and possibly other neurodegenerative disorders; help to preserve the proper structure of bone and cartilage; and possibly aid in the prevention and control of autoimmunity. While metformin and berberine appear to have the greatest utility as clinical AMPK activators-as reflected by their efficacy in diabetes management-regular ingestion of vinegar, as well as moderate alcohol consumption, may also achieve a modest degree of health-protective AMPK activation. The activation of AMPK achievable with any of these measures may be potentiated by clinical doses of the drug salicylate, which can bind to AMPK and activate it allosterically.
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Affiliation(s)
- Mark F McCarty
- Catalytic Longevity, 7831 Rush Rose Dr., Apt. 316, Carlsbad, CA, 92009, USA,
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Serini S, Fasano E, Celleno L, Cittadini A, Calviello G. Potential of long-chain n-3 polyunsaturated fatty acids in melanoma prevention. Nutr Rev 2014; 72:255-66. [PMID: 24665956 DOI: 10.1111/nure.12093] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The possible antineoplastic activity of dietary long-chain n-3 polyunsaturated fatty acids (LC n-3 PUFAs) has been supported by ample preclinical studies that have identified a number of molecular factors and pathways affected by these fatty acids and involved in cell growth, apoptosis, invasion, and angiogenesis. The aim of this critical review is to assess the current state of knowledge on the potential anticancer effects of LC n-3 PUFAs against malignant melanoma, one of the most common cancers among Western populations. The results of preclinical as well as human observational and interventional studies investigating the effects of LC n-3 PUFAs in melanoma were examined. Overall, the analysis of the literature reveals that, even though a large body of information is available, further effort is needed to identify the main molecular targets of LC n-3 PUFAs in melanoma. Moreover, additional well-designed human observational studies are essential to shed further light on the issue. The results of these studies could provide support and specific information for the development of clinical studies, especially those performed in combination with conventional or innovative antineoplastic therapies.
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Affiliation(s)
- Simona Serini
- Institute of General Pathology, Catholic University, Rome, Italy
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40
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Zago M, Sheridan JA, Nair P, Rico de Souza A, Gallouzi IE, Rousseau S, Di Marco S, Hamid Q, Eidelman DH, Baglole CJ. Aryl hydrocarbon receptor-dependent retention of nuclear HuR suppresses cigarette smoke-induced cyclooxygenase-2 expression independent of DNA-binding. PLoS One 2013; 8:e74953. [PMID: 24086407 PMCID: PMC3785509 DOI: 10.1371/journal.pone.0074953] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2013] [Accepted: 08/07/2013] [Indexed: 12/02/2022] Open
Abstract
The aryl hydrocarbon receptor (AhR), a ligand-activated transcription factor that responds to man-made environmental toxicants, has emerged as an endogenous regulator of cyclooxygenase-2 (Cox-2) by a mechanism that is poorly understood. In this study, we first used AhR-deficient (AhR−/−) primary pulmonary cells, together with pharmacological tools to inhibit new RNA synthesis, to show that the AhR is a prominent factor in the destabilization of Cox-2 mRNA. The destabilization of Cox-2 mRNA and subsequent suppression of cigarette smoke-induced COX-2 protein expression by the AhR was independent of its ability to bind the dioxin response element (DRE), thereby differentiating the DRE-driven toxicological AhR pathway from its anti-inflammatory abilities. We further describe that the AhR destabilizes Cox-2 mRNA by sequestering HuR within the nucleus. The role of HuR in AhR stabilization of Cox-2 mRNA was confirmed by knockdown of HuR, which resulted in rapid Cox-2 mRNA degradation. Finally, in the lungs of AhR−/− mice exposed to cigarette smoke, there was little Cox-2 mRNA despite robust COX-2 protein expression, a finding that correlates with almost exclusive cytoplasmic HuR within the lungs of AhR−/− mice. Therefore, we propose that the AhR plays an important role in suppressing the expression of inflammatory proteins, a function that extends beyond the ability of the AhR to respond to man-made toxicants. These findings open the possibility that a DRE-independent AhR pathway may be exploited therapeutically as an anti-inflammatory target.
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MESH Headings
- Animals
- Azo Compounds/pharmacology
- Cell Nucleus/drug effects
- Cell Nucleus/metabolism
- Cells, Cultured
- Cyclooxygenase 2/genetics
- Cyclooxygenase 2/metabolism
- DNA/metabolism
- ELAV Proteins/metabolism
- Fibroblasts/drug effects
- Fibroblasts/enzymology
- Fibroblasts/pathology
- Humans
- Lung/pathology
- Mice
- Models, Biological
- Prostaglandins/biosynthesis
- Protein Binding/drug effects
- Protein Structure, Tertiary
- Protein Transport/drug effects
- Pyrazoles/pharmacology
- RNA Stability/drug effects
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- RNA, Small Interfering/metabolism
- Receptors, Aryl Hydrocarbon/antagonists & inhibitors
- Receptors, Aryl Hydrocarbon/chemistry
- Receptors, Aryl Hydrocarbon/deficiency
- Receptors, Aryl Hydrocarbon/metabolism
- Smoking/adverse effects
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Affiliation(s)
- Michela Zago
- Department of Medicine, McGill University, Montreal, Quebec, Canada
| | | | - Parameswaran Nair
- Department of Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Angela Rico de Souza
- Research Institute of the McGill University Health Centre, Montreal, Quebec, Canada
| | - Imed-Eddine Gallouzi
- Department of Biochemistry and the Goodman Cancer Centre, McGill University, Montreal, Quebec, Canada
| | - Simon Rousseau
- Department of Medicine, McGill University, Montreal, Quebec, Canada
- Research Institute of the McGill University Health Centre, Montreal, Quebec, Canada
| | - Sergio Di Marco
- Department of Biochemistry and the Goodman Cancer Centre, McGill University, Montreal, Quebec, Canada
| | - Qutayba Hamid
- Department of Medicine, McGill University, Montreal, Quebec, Canada
- Research Institute of the McGill University Health Centre, Montreal, Quebec, Canada
| | - David H. Eidelman
- Department of Medicine, McGill University, Montreal, Quebec, Canada
- Research Institute of the McGill University Health Centre, Montreal, Quebec, Canada
| | - Carolyn J. Baglole
- Department of Medicine, McGill University, Montreal, Quebec, Canada
- Research Institute of the McGill University Health Centre, Montreal, Quebec, Canada
- * E-mail:
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41
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Schulz S, Doller A, Pendini NR, Wilce JA, Pfeilschifter J, Eberhardt W. Domain-specific phosphomimetic mutation allows dissection of different protein kinase C (PKC) isotype-triggered activities of the RNA binding protein HuR. Cell Signal 2013; 25:2485-95. [PMID: 23978401 DOI: 10.1016/j.cellsig.2013.08.003] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Revised: 08/06/2013] [Accepted: 08/15/2013] [Indexed: 01/21/2023]
Abstract
The ubiquitous mRNA binding protein human antigen R (HuR) participates in the post-transcriptional regulation of many AU-rich element (ARE)-bearing mRNAs. Previously, by using in vitro kinase assay, we have identified serines (Ser) 158, 221 and 318 as targets of protein kinase C (PKC)-triggered phosphorylation. In this study, we tested whether GFP- or GST-tagged HuR constructs bearing a phosphomimetic Ser (S)-to-Asp (D) substitution at the different PKC target sites, would affect different HuR functions including HuR nucleo-cytoplasmic redistribution and binding to different types of ARE-containing mRNAs. The phosphomimetic GFP-tagged HuR protein bearing a phosphomimetic substitution in the hinge region of HuR (HuR-S221D) showed an increased cytoplasmic abundance when compared to wild-type HuR. Conversely, data from in vitro kinase assay and electrophoretic mobility shift assay (EMSA), implicates that phosphorylation at Ser 221 is not relevant for mRNA binding of HuR. Quantification of in vitro binding affinities of GST-tagged wild-type HuR and corresponding HuR proteins bearing a phosphomimetic substitution in either RRM2 (HuR-S158D) or in RRM3 (HuR-S318D) by microscale thermophoresis (MST) indicates a specific binding of wild-type HuR to type I, II or type III-ARE-oligonucleotides in the high nanomolar range. Interestingly, phosphomimetic mutation at position 158 or 318 had a negative influence on HuR binding to type I- and type II-ARE-mRNAs whereas it significantly enhanced HuR affinity to a type III-ARE substrate. Our data suggest that differential phosphorylation of HuR by PKCs at different HuR domains coordinates subcellular HuR distribution and leads to a preferential binding to U-rich bearing target mRNA.
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Affiliation(s)
- Sebastian Schulz
- pharmazentrum frankfurt/ZAFES, Klinikum der Johann Wolfgang Goethe-Universität, Frankfurt am Main, Germany
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42
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Herjan T, Yao P, Qian W, Li X, Liu C, Bulek K, Sun D, Yang WP, Zhu J, He A, Carman JA, Erzurum SC, Lipshitz HD, Fox PL, Hamilton TA, Li X. HuR is required for IL-17-induced Act1-mediated CXCL1 and CXCL5 mRNA stabilization. THE JOURNAL OF IMMUNOLOGY 2013; 191:640-9. [PMID: 23772036 DOI: 10.4049/jimmunol.1203315] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
IL-17, a major inflammatory cytokine plays a critical role in the pathogenesis of many autoimmune inflammatory diseases. In this study, we report a new function of RNA-binding protein HuR in IL-17-induced Act1-mediated chemokine mRNA stabilization. HuR deficiency markedly reduced IL-17-induced chemokine expression due to increased mRNA decay. Act1-mediated HuR polyubiquitination was required for the binding of HuR to CXCL1 mRNA, leading to mRNA stabilization. Although IL-17 induced the coshift of Act1 and HuR to the polysomal fractions in a sucrose gradient, HuR deficiency reduced the ratio of translation-active/translation-inactive IL-17-induced chemokine mRNAs. Furthermore, HuR deletion in distal lung epithelium attenuated IL-17-induced neutrophilia. In summary, HuR functions to couple receptor-proximal signaling to posttranscriptional machinery, contributing to IL-17-induced inflammation.
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Affiliation(s)
- Tomasz Herjan
- Department of Immunology, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, OH 44195, USA
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43
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Zhu Z, Wang B, Bi J, Zhang C, Guo Y, Chu H, Liang X, Zhong C, Wang J. Cytoplasmic HuR expression correlates with P-gp, HER-2 positivity, and poor outcome in breast cancer. Tumour Biol 2013; 34:2299-308. [PMID: 23605320 DOI: 10.1007/s13277-013-0774-3] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2013] [Accepted: 03/25/2013] [Indexed: 12/18/2022] Open
Abstract
HuR is an ubiquitously expressed RNA-binding protein that stabilizes messenger RNA and regulates translation. This protein has been shown to play an important role in carcinogenesis and cancer progression. P-glycoprotein (P-gp) is the product of the multidrug resistance 1 gene, and the overexpression of P-gp induces multidrug resistance and represents a major obstacle in cancer chemotherapy. The purpose of this study was to determine the expression of HuR and P-gp in human breast cancer tissues and analyze the relationship between HuR or P-gp expression and the clinical-pathological variables and patient outcomes. Immunohistochemistry was used to determine HuR and P-gp expression in 82 human breast cancer tissues and 20 matched adjacent noncancerous tissues. Additionally, 16 benign breast tumor samples were used as controls. The overexpression of cytoplasmic HuR was found in breast cancer but not in the matched adjacent noncancerous tissues or benign breast tumors. The expression levels of cytoplasmic HuR were significantly associated with increased age, high nuclear grade, and the positive expression of the ER, PR, and HER-2/neu. HuR was also associated with the expression of P-gp protein. Furthermore, univariate analysis indicates that patients with high expression levels of cytoplasmic HuR or P-gp had significantly reduced survival compared to patients with low expression levels. A multivariate analysis showed that age at diagnosis, nuclear grade, and cytoplasmic HuR positivity were independent indicators for disease-free survival and overall survival in patients with breast cancer. In conclusion, cytoplasmic HuR expression detected by immunohistochemical staining is a negative prognostic indicator for survival in patients with breast cancer.
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Affiliation(s)
- Zhongpeng Zhu
- Department of Oncology, General Hospital, Jinan Command of People's Liberation Army, Shifan Street 25, Tianqiao District, Jinan, 250031, China
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44
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Hsp27 and F-box protein β-TrCP promote degradation of mRNA decay factor AUF1. Mol Cell Biol 2013; 33:2315-26. [PMID: 23530064 DOI: 10.1128/mcb.00931-12] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Activation of the mitogen-activated protein (MAP) pathway kinases p38 and MK2 induces phosphorylation of the chaperone Hsp27 and stabilization of mRNAs containing AU-rich elements (AREs) (ARE-mRNAs). Likewise, expression of phosphomimetic mutant forms of Hsp27 also stabilizes ARE-mRNAs. It appears to perform this function by promoting degradation of the ARE-mRNA decay factor AUF1 by proteasomes. In this study, we examined the molecular mechanism linking Hsp27 phosphorylation to AUF1 degradation by proteasomes. AUF1 is a target of β-TrCP, the substrate recognition subunit of the E3 ubiquitin ligase Skp1-cullin-F-box protein complex, SCF(β-TrCP). Depletion of β-TrCP stabilized AUF1. In contrast, overexpression of β-TrCP enhanced ubiquitination and degradation of AUF1 and led to stabilization of reporter mRNAs containing cytokine AREs. Enhanced AUF1 degradation required expression of phosphomimetic mutant forms of both Hsp27 and AUF1. Our results suggest that a signaling axis composed of p38 MAP kinase-MK2-Hsp27-β-TrCP may promote AUF1 degradation by proteasomes and stabilization of cytokine ARE-mRNAs.
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45
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Protein kinase D2 and heat shock protein 90 beta are required for BCL6-associated zinc finger protein mRNA stabilization induced by vascular endothelial growth factor-A. Angiogenesis 2013; 16:675-88. [DOI: 10.1007/s10456-013-9345-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2012] [Accepted: 03/08/2013] [Indexed: 10/27/2022]
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46
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The novel tumor suppressor NOL7 post-transcriptionally regulates thrombospondin-1 expression. Oncogene 2012; 32:4377-86. [PMID: 23085760 DOI: 10.1038/onc.2012.464] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2012] [Revised: 08/22/2012] [Accepted: 08/24/2012] [Indexed: 12/30/2022]
Abstract
Thrombospondin-1 (TSP-1) is an endogenous inhibitor of angiogenesis whose expression suppresses tumor growth in vivo. Like many angiogenesis-related genes, TSP-1 expression is tightly controlled by various mechanisms, but there is little data regarding the contribution of post-transcriptional processing to this regulation. NOL7 is a novel tumor suppressor that induces an antiangiogenic phenotype and suppresses tumor growth, in part through upregulation of TSP-1. Here we demonstrate that NOL7 is an mRNA-binding protein that must localize to the nucleoplasm to exert its antiangiogenic and tumor suppressive effects. There, it associates with the RNA-processing machinery and specifically interacts with TSP-1 mRNA through its 3'UTR. Reintroduction of NOL7 into SiHa cells increases luciferase expression through interaction with the TSP-1 3'UTR at both the mRNA and protein levels. NOL7 also increases endogenous TSP-1 mRNA half-life. Further, NOL7 post-transcriptional stabilization is observed in a subset of angiogenesis-related mRNAs, suggesting that the stabilization of TSP-1 may be part of a larger novel mechanism. These data demonstrate that NOL7 significantly alters TSP-1 expression and may be a master regulator that coordinates the post-transcriptional expression of key signaling factors critical for the regulation of the angiogenic phenotype.
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47
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Brewster BL, Rossiello F, French JD, Edwards SL, Wong M, Wronski A, Whiley P, Waddell N, Chen X, Bove B, Hopper JL, John EM, Andrulis I, Daly M, Volorio S, Bernard L, Peissel B, Manoukian S, Barile M, Pizzamiglio S, Verderio P, Spurdle AB, Radice P, Godwin AK, Southey MC, Brown MA, Peterlongo P. Identification of fifteen novel germline variants in the BRCA1 3'UTR reveals a variant in a breast cancer case that introduces a functional miR-103 target site. Hum Mutat 2012; 33:1665-75. [PMID: 22753153 DOI: 10.1002/humu.22159] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2012] [Accepted: 06/20/2012] [Indexed: 01/05/2023]
Abstract
Mutations in the BRCA1 gene confer a substantial increase in breast cancer risk, yet routine clinical genetic screening is limited to the coding regions and intron-exon boundaries, precluding the identification of mutations in noncoding and untranslated regions (UTR). As 3'UTR mutations can influence cancer susceptibility by altering protein and microRNA (miRNA) binding regions, we screened the BRCA1 3'UTR for mutations in a large series of BRCA-mutation negative, population and clinic-based breast cancer cases, and controls. Fifteen novel BRCA1 3'UTR variants were identified, the majority of which were unique to either cases or controls. Using luciferase reporter assays, three variants found in cases, c.* 528G>C, c.* 718A>G, and c.* 1271T>C and four found in controls, c.* 309T>C, c.* 379G>A, c.* 823C>T, and c.* 264C>T, reduced 3'UTR activity (P < 0.02), whereas two variants found in cases, c.* 291C>T and c.* 1139G>T, increased 3'UTR activity (P < 0.01). Three case variants, c.* 718A>G, c.* 800T>C, and c.* 1340_1342delTGT, were predicted to create new miRNA binding sites and c.* 1340_1342delTGT caused a reduction (25%, P = 0.0007) in 3'UTR reporter activity when coexpressed with the predicted targeting miRNA, miR-103. This is the most comprehensive identification and analysis of BRCA1 3'UTR variants published to date.
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Affiliation(s)
- Brooke L Brewster
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Australia.
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48
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HuR thermal stability is dependent on domain binding and upon phosphorylation. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2012; 41:597-605. [PMID: 22706953 DOI: 10.1007/s00249-012-0827-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2011] [Revised: 05/10/2012] [Accepted: 05/28/2012] [Indexed: 12/22/2022]
Abstract
Human antigen R (HuR) is a multitasking RNA binding protein involved in posttranscriptional regulation by recognizing adenine- and uracile-rich elements placed at the 3'-untranslated regions of messenger RNAs (mRNAs). The modular architecture of the protein, which consists of two N-terminal RNA recognition motifs (RRMs) in tandem spaced from a third one by a nuclear-cytoplasmic shuttling sequence, controls the stability of many mRNA targets, as well as their translation rates. A higher level of regulation comes from the fact that both localization and function of HuR are strictly regulated by phosphorylation. Here, we report how the thermal stability of RRM2 is decreased by the presence of RRM1, indicating that both domains are interacting in solution. In addition, even though no significant structural changes are observed among mutants of HuR RRM12 mimicking phosphorylated species, slight differences in stability are appreciable, which may explain the RNA binding activity of HuR.
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49
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Matoulkova E, Michalova E, Vojtesek B, Hrstka R. The role of the 3' untranslated region in post-transcriptional regulation of protein expression in mammalian cells. RNA Biol 2012; 9:563-76. [PMID: 22614827 DOI: 10.4161/rna.20231] [Citation(s) in RCA: 249] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The untranslated regions (UTRs) at the 3'end of mRNA transcripts contain important sequences that influence the fate of mRNA and thus proteosynthesis. In this review, we summarize the information known to date about 3'end processing, sequence characteristics including related binding proteins and the role of 3'UTRs in several selected signaling pathways to delineate their importance in the regulatory processes in mammalian cells. In addition to reviewing recent advances in the more well known aspects, such as cleavage and polyadenylation processes that influence mRNA stability and location, we concentrate on some newly emerging concepts of the role of the 3'UTR, including alternative polyadenylation sites in relation to proliferation and differentiation and the recognition of the multi-functional properties of non-coding RNAs, including miRNAs that commonly target the 3'UTR. The emerging picture is of a highly complex set of regulatory systems that include autoregulation, cooperativity and competition to fine tune proteosynthesis in context-dependent manners.
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50
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Sung S, Park Y, Jo JR, Jung NK, Song DK, Bae J, Keum DY, Kim JB, Park GY, Jang BC, Park JW. Overexpression of cyclooxygenase-2 in NCI-H292 human alveolar epithelial carcinoma cells: roles of p38 MAPK, ERK-1/2, and PI3K/PKB signaling proteins. J Cell Biochem 2012; 112:3015-24. [PMID: 21678473 DOI: 10.1002/jcb.23226] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Evidence suggests overexpression of COX-2 and its role in many human cancers, including lung. However, the regulatory mechanism underlying COX-2 overexpression in lung cancer is not fully understood. We herein investigated whether COX-2 is overexpressed in human airway cancer cell lines, including A549 (lung), Hep-2 (bronchial), and NCI-H292 (alveolar). When grown in cell culture medium containing 10% FBS (serum), of note, there was strong and transient induction of COX-2 protein and mRNA in NCI-H292 cells, but little or low COX-2 expression is seen in A549 or Hep-2 cells. Interestingly, strong and sustained activities of ERK-1/2, JNK-1/2, p38 MAPK, and PKB were also shown in NCI-H292 cells grown in presence of serum. Profoundly, results of pharmacological inhibition studies demonstrated that the serum-dependent COX-2 up-regulation in NCI-H292 cells is attributed to not only the p38 MAPK-, PI3K/PKB-, and ERK-1/2-mediated COX-2 transcriptional up-regulation but also the p38 MAPK- and ERK-1/2-mediated post-transcriptional COX-2 mRNA stabilization. Of further note, it was shown that the ERK-1/2 and PI3K/PKB (but not COX-2, p38 MAPK, and JNK-1/2) activities are necessary for growth of NCI-H292 cells. These findings collectively demonstrate for the first time that COX-2 expression is transiently up-regulated by serum addition in NCI-H292 cells and the serum-induced COX-2 expression is closely linked to the p38 MAPK-, ERK-1/2-, and PI3K/PKB-mediated COX-2 transcriptional and post-transcriptional up-regulation.
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Affiliation(s)
- Suhaeng Sung
- Department of Medical Genetic Engineering, Keimyung University School of Medicine, 1000 Dalgubeol-daero, Dalseo-gu, Daegu 704-701, Korea
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