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Misao T, Fukushima K, Fujino H. Novel anti-cancer effect of 2-arachidonoylglycerol via processing body formation in HCA-7 human colon cancer cells. Prostaglandins Other Lipid Mediat 2024; 174:106861. [PMID: 38876400 DOI: 10.1016/j.prostaglandins.2024.106861] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2024] [Revised: 06/04/2024] [Accepted: 06/11/2024] [Indexed: 06/16/2024]
Abstract
The endocannabinoid 2-arachidonoylglycerol (2-AG) has been reported to exhibit anticancer effects, including against colorectal cancer (CRC); however, the detailed mechanisms have not been clarified. Herein, we demonstrated that 2-AG suppressed cyclooxygenase-2 (COX-2) expression induced by prostaglandin E2 in human colon cancer HCA-7 cells. The suppression of COX-2 expression by 2-AG was through the acceleration of processing body (P-body) formation followed by COX-2 mRNA degradation. These effects were restored by TAK-715, a specific inhibitor of p38 MAPK. Therefore, the effect of 2-AG on COX-2 may be distinct from conventional non-steroidal anti-inflammatory drugs (NSAIDs). NSAIDs inhibit the function of COX-2, whereas 2-AG suppresses the protein expression of COX-2. Recently, the cardiovascular risks of NSAIDs were reported by the Food and Drug Administration in the United States. Therefore, elucidation of the effect of 2-AG is expected to contribute to the development of an alternative and novel therapeutic option that would have no or fewer risks regarding cardiovascular events.
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Affiliation(s)
- Takaya Misao
- Department of Pharmacology for Life Sciences, Graduate School of Pharmaceutical Sciences & Graduate School of Biomedical Sciences, Tokushima University, Tokushima 770-8505, Japan
| | - Keijo Fukushima
- Department of Pharmacology for Life Sciences, Graduate School of Pharmaceutical Sciences & Graduate School of Biomedical Sciences, Tokushima University, Tokushima 770-8505, Japan
| | - Hiromichi Fujino
- Department of Pharmacology for Life Sciences, Graduate School of Pharmaceutical Sciences & Graduate School of Biomedical Sciences, Tokushima University, Tokushima 770-8505, Japan.
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2
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Bermudez Y, Hatfield D, Muller M. A Balancing Act: The Viral-Host Battle over RNA Binding Proteins. Viruses 2024; 16:474. [PMID: 38543839 PMCID: PMC10974049 DOI: 10.3390/v16030474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Revised: 03/16/2024] [Accepted: 03/18/2024] [Indexed: 04/01/2024] Open
Abstract
A defining feature of a productive viral infection is the co-opting of host cell resources for viral replication. Despite the host repertoire of molecular functions and biological counter measures, viruses still subvert host defenses to take control of cellular factors such as RNA binding proteins (RBPs). RBPs are involved in virtually all steps of mRNA life, forming ribonucleoprotein complexes (mRNPs) in a highly ordered and regulated process to control RNA fate and stability in the cell. As such, the hallmark of the viral takeover of a cell is the reshaping of RNA fate to modulate host gene expression and evade immune responses by altering RBP interactions. Here, we provide an extensive review of work in this area, particularly on the duality of the formation of RNP complexes that can be either pro- or antiviral. Overall, in this review, we highlight the various ways viruses co-opt RBPs to regulate RNA stability and modulate the outcome of infection by gathering novel insights gained from research studies in this field.
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Affiliation(s)
| | | | - Mandy Muller
- Department of Microbiology, University of Massachusetts, Amherst, MA 01003, USA; (Y.B.); (D.H.)
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3
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Fang L, Zhang L, Wang M, He Y, Yang J, Huang Z, Tan Y, Fang K, Li J, Sun Z, Li Y, Tang Y, Liang W, Cui H, Zhu Q, Wu Z, Li Y, Hu Y, Chen W. Pooled CRISPR Screening Identifies P-Bodies as Repressors of Cancer Epithelial-Mesenchymal Transition. Cancer Res 2024; 84:659-674. [PMID: 38190710 DOI: 10.1158/0008-5472.can-23-1693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Revised: 11/07/2023] [Accepted: 01/03/2024] [Indexed: 01/10/2024]
Abstract
Epithelial-mesenchymal transition (EMT) is a fundamental cellular process frequently hijacked by cancer cells to promote tumor progression, especially metastasis. EMT is orchestrated by a complex molecular network acting at different layers of gene regulation. In addition to transcriptional regulation, posttranscriptional mechanisms may also play a role in EMT. Here, we performed a pooled CRISPR screen analyzing the influence of 1,547 RNA-binding proteins on cell motility in colon cancer cells and identified multiple core components of P-bodies (PB) as negative modulators of cancer cell migration. Further experiments demonstrated that PB depletion by silencing DDX6 or EDC4 could activate hallmarks of EMT thereby enhancing cell migration in vitro as well as metastasis formation in vivo. Integrative multiomics analysis revealed that PBs could repress the translation of the EMT driver gene HMGA2, which contributed to PB-meditated regulation of EMT. This mechanism is conserved in other cancer types. Furthermore, endoplasmic reticulum stress was an intrinsic signal that induced PB disassembly and translational derepression of HMGA2. Taken together, this study has identified a function of PBs in the regulation of EMT in cancer. SIGNIFICANCE Systematic investigation of the influence of posttranscriptional regulation on cancer cell motility established a connection between P-body-mediated translational control and EMT, which could be therapeutically exploited to attenuate metastasis formation.
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Affiliation(s)
- Liang Fang
- Shenzhen Key Laboratory of Gene Regulation and Systems Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, Guangdong, P.R. China
- Department of Systems Biology, School of Life Science, Southern University of Science and Technology, Shenzhen, Guangdong, P.R. China
- Academy for Advanced Interdisciplinary Studies, Southern University of Science and Technology, Shenzhen, Guangdong, P.R. China
| | - Li Zhang
- Shenzhen Key Laboratory of Gene Regulation and Systems Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, Guangdong, P.R. China
- Department of Systems Biology, School of Life Science, Southern University of Science and Technology, Shenzhen, Guangdong, P.R. China
| | - Mengran Wang
- Shenzhen Key Laboratory of Gene Regulation and Systems Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, Guangdong, P.R. China
- Department of Systems Biology, School of Life Science, Southern University of Science and Technology, Shenzhen, Guangdong, P.R. China
| | - Yuhao He
- Shenzhen Key Laboratory of Gene Regulation and Systems Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, Guangdong, P.R. China
- Department of Systems Biology, School of Life Science, Southern University of Science and Technology, Shenzhen, Guangdong, P.R. China
| | - Jiao Yang
- Shenzhen Key Laboratory of Gene Regulation and Systems Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, Guangdong, P.R. China
- Department of Systems Biology, School of Life Science, Southern University of Science and Technology, Shenzhen, Guangdong, P.R. China
| | - Zengjin Huang
- Shenzhen Key Laboratory of Gene Regulation and Systems Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, Guangdong, P.R. China
- Department of Systems Biology, School of Life Science, Southern University of Science and Technology, Shenzhen, Guangdong, P.R. China
| | - Ying Tan
- Shenzhen Key Laboratory of Gene Regulation and Systems Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, Guangdong, P.R. China
- Department of Systems Biology, School of Life Science, Southern University of Science and Technology, Shenzhen, Guangdong, P.R. China
| | - Ke Fang
- Department of Biomedical Engineering, College of Engineering, Southern University of Science and Technology, Shenzhen, Guangdong, P.R. China
| | - Jun Li
- Shenzhen Key Laboratory of Gene Regulation and Systems Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, Guangdong, P.R. China
- Department of Systems Biology, School of Life Science, Southern University of Science and Technology, Shenzhen, Guangdong, P.R. China
| | - Zhiyuan Sun
- Shenzhen Key Laboratory of Gene Regulation and Systems Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, Guangdong, P.R. China
- Department of Systems Biology, School of Life Science, Southern University of Science and Technology, Shenzhen, Guangdong, P.R. China
| | - Yanping Li
- Shenzhen Key Laboratory of Gene Regulation and Systems Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, Guangdong, P.R. China
- Department of Systems Biology, School of Life Science, Southern University of Science and Technology, Shenzhen, Guangdong, P.R. China
| | - Yisen Tang
- Shenzhen Key Laboratory of Gene Regulation and Systems Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, Guangdong, P.R. China
- Department of Systems Biology, School of Life Science, Southern University of Science and Technology, Shenzhen, Guangdong, P.R. China
| | - Weizheng Liang
- Shenzhen Key Laboratory of Gene Regulation and Systems Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, Guangdong, P.R. China
- Department of Systems Biology, School of Life Science, Southern University of Science and Technology, Shenzhen, Guangdong, P.R. China
- Central Laboratory, The First Affiliated Hospital of Hebei North University, Zhangjiakou, Hebei, P.R. China
| | - Huanhuan Cui
- Shenzhen Key Laboratory of Gene Regulation and Systems Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, Guangdong, P.R. China
- Department of Systems Biology, School of Life Science, Southern University of Science and Technology, Shenzhen, Guangdong, P.R. China
- Academy for Advanced Interdisciplinary Studies, Southern University of Science and Technology, Shenzhen, Guangdong, P.R. China
| | - Qionghua Zhu
- Shenzhen Key Laboratory of Gene Regulation and Systems Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, Guangdong, P.R. China
- Department of Systems Biology, School of Life Science, Southern University of Science and Technology, Shenzhen, Guangdong, P.R. China
| | - Zhe Wu
- Key Laboratory of Molecular Design for Plant Cell Factory of Guangdong Higher Education Institutes, Institute of Plant and Food Science, Department of Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, Guangdong, P.R. China
| | - Yiming Li
- Department of Biomedical Engineering, College of Engineering, Southern University of Science and Technology, Shenzhen, Guangdong, P.R. China
| | - Yuhui Hu
- Shenzhen Key Laboratory of Gene Regulation and Systems Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, Guangdong, P.R. China
- Department of Pharmacology, School of Medicine, Southern University of Science and Technology, Shenzhen, Guangdong, P.R. China
| | - Wei Chen
- Shenzhen Key Laboratory of Gene Regulation and Systems Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, Guangdong, P.R. China
- Department of Systems Biology, School of Life Science, Southern University of Science and Technology, Shenzhen, Guangdong, P.R. China
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Kaposi's sarcoma-associated herpesvirus (KSHV) utilizes the NDP52/CALCOCO2 selective autophagy receptor to disassemble processing bodies. PLoS Pathog 2023; 19:e1011080. [PMID: 36634147 PMCID: PMC9876383 DOI: 10.1371/journal.ppat.1011080] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Revised: 01/25/2023] [Accepted: 12/22/2022] [Indexed: 01/13/2023] Open
Abstract
Kaposi's sarcoma-associated herpesvirus (KSHV) causes the inflammatory and angiogenic endothelial cell neoplasm, Kaposi's sarcoma (KS). We previously demonstrated that the KSHV Kaposin B (KapB) protein promotes inflammation via the disassembly of cytoplasmic ribonucleoprotein granules called processing bodies (PBs). PBs modify gene expression by silencing or degrading labile messenger RNAs (mRNAs), including many transcripts that encode inflammatory or angiogenic proteins associated with KS disease. Although our work implicated PB disassembly as one of the causes of inflammation during KSHV infection, the precise mechanism used by KapB to elicit PB disassembly was unclear. Here we reveal a new connection between the degradative process of autophagy and PB disassembly. We show that both latent KSHV infection and KapB expression enhanced autophagic flux via phosphorylation of the autophagy regulatory protein, Beclin. KapB was necessary for this effect, as infection with a recombinant virus that does not express the KapB protein did not induce Beclin phosphorylation or autophagic flux. Moreover, we showed that PB disassembly mediated by KSHV or KapB, depended on autophagy genes and the selective autophagy receptor NDP52/CALCOCO2 and that the PB scaffolding protein, Pat1b, co-immunoprecipitated with NDP52. These studies reveal a new role for autophagy and the selective autophagy receptor NDP52 in promoting PB turnover and the concomitant synthesis of inflammatory molecules during KSHV infection.
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5
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Zhang Y, Shen H, Xu J, Qian SF. Antecedents of attitude and their impact on behavioral intention in the staycation context. Front Psychol 2022; 13:996788. [PMID: 36148117 PMCID: PMC9488153 DOI: 10.3389/fpsyg.2022.996788] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Accepted: 08/12/2022] [Indexed: 11/13/2022] Open
Abstract
The year 2020 and 2021 have been decimated by the pandemic, leading to outbound vacations largely scrapped. Staycation, a typical domestic journal, has then been adopted by those who are tired of self-isolation for so long. This study aims to explore and assess the drivers exerting impact on attitude of tourists toward staycation and the interrelationship among the research constructs is also examined. A quantitative analysis is employed for evaluating the roles of reduced risk perception, benign envy, and perceived benefits as they exert the effect on attitude toward staycation. An online questionnaire survey was used, and a total of 213 samples were collected from target respondents in Hong Kong, which were still under lockdown at the time of the study. The results of the study showed that reduced risk perception, benign envy as well as perceived benefits will influence tourists' attitude toward staycation. The managerial and theoretical implications of the results are discussed based on the significant relationships identified in the study.
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Affiliation(s)
- Yating Zhang
- Faculty of International Tourism and Management, City University of Macau, Macau, Macau SAR, China
| | - Huawen Shen
- Faculty of International Tourism and Management, City University of Macau, Macau, Macau SAR, China
| | - Jiajia Xu
- Faculty of International Tourism and Management, City University of Macau, Macau, Macau SAR, China
| | - Stella Fang Qian
- Faculty of Business Administration, University of Macau, Macau, Macau SAR, China
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Kleer M, Mulloy RP, Robinson CA, Evseev D, Bui-Marinos MP, Castle EL, Banerjee A, Mubareka S, Mossman K, Corcoran JA. Human coronaviruses disassemble processing bodies. PLoS Pathog 2022; 18:e1010724. [PMID: 35998203 PMCID: PMC9439236 DOI: 10.1371/journal.ppat.1010724] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 09/02/2022] [Accepted: 07/04/2022] [Indexed: 11/21/2022] Open
Abstract
A dysregulated proinflammatory cytokine response is characteristic of severe coronavirus infections caused by SARS-CoV-2, yet our understanding of the underlying mechanism responsible for this imbalanced immune response remains incomplete. Processing bodies (PBs) are cytoplasmic membraneless ribonucleoprotein granules that control innate immune responses by mediating the constitutive decay or suppression of mRNA transcripts, including many that encode proinflammatory cytokines. PB formation promotes turnover or suppression of cytokine RNAs, whereas PB disassembly corresponds with the increased stability and/or translation of these cytokine RNAs. Many viruses cause PB disassembly, an event that can be viewed as a switch that rapidly relieves cytokine RNA repression and permits the infected cell to respond to viral infection. Prior to this submission, no information was known about how human coronaviruses (CoVs) impacted PBs. Here, we show SARS-CoV-2 and the common cold CoVs, OC43 and 229E, induced PB loss. We screened a SARS-CoV-2 gene library and identified that expression of the viral nucleocapsid (N) protein from SARS-CoV-2 was sufficient to mediate PB disassembly. RNA fluorescent in situ hybridization revealed that transcripts encoding TNF and IL-6 localized to PBs in control cells. PB loss correlated with the increased cytoplasmic localization of these transcripts in SARS-CoV-2 N protein-expressing cells. Ectopic expression of the N proteins from five other human coronaviruses (OC43, MERS, 229E, NL63 and SARS-CoV) did not cause significant PB disassembly, suggesting that this feature is unique to SARS-CoV-2 N protein. These data suggest that SARS-CoV-2-mediated PB disassembly contributes to the dysregulation of proinflammatory cytokine production observed during severe SARS-CoV-2 infection.
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Affiliation(s)
- Mariel Kleer
- Microbiology, Immunology and Infectious Diseases Department, University of Calgary, Calgary, Alberta, Canada
- Charbonneau Cancer Research Institute, University of Calgary, Calgary, Alberta, Canada
- Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
| | - Rory P. Mulloy
- Microbiology, Immunology and Infectious Diseases Department, University of Calgary, Calgary, Alberta, Canada
- Charbonneau Cancer Research Institute, University of Calgary, Calgary, Alberta, Canada
- Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
| | - Carolyn-Ann Robinson
- Microbiology, Immunology and Infectious Diseases Department, University of Calgary, Calgary, Alberta, Canada
- Charbonneau Cancer Research Institute, University of Calgary, Calgary, Alberta, Canada
- Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
| | - Danyel Evseev
- Microbiology, Immunology and Infectious Diseases Department, University of Calgary, Calgary, Alberta, Canada
- Charbonneau Cancer Research Institute, University of Calgary, Calgary, Alberta, Canada
- Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
| | - Maxwell P. Bui-Marinos
- Microbiology, Immunology and Infectious Diseases Department, University of Calgary, Calgary, Alberta, Canada
- Charbonneau Cancer Research Institute, University of Calgary, Calgary, Alberta, Canada
- Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
| | - Elizabeth L. Castle
- School of Biomedical Engineering, University of British Columbia, Vancouver, British Columbia, Canada
| | - Arinjay Banerjee
- Vaccine and Infectious Disease Organization, University of Saskatchewan; Saskatoon, Saskatchewan, Canada
- Department of Veterinary Microbiology, Western College of Veterinary Medicine, University of Saskatchewan; Saskatoon, Saskatchewan, Canada
- Department of Biology, University of Waterloo; Waterloo, Ontario, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - Samira Mubareka
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
- Sunnybrook Research Institute, Toronto, Ontario, Canada
| | - Karen Mossman
- Department of Medicine, Master University, Hamilton, Ontario, Canada
- Institute for Infectious Disease Research, McMaster University, Hamilton, Ontario, Canada
| | - Jennifer A. Corcoran
- Microbiology, Immunology and Infectious Diseases Department, University of Calgary, Calgary, Alberta, Canada
- Charbonneau Cancer Research Institute, University of Calgary, Calgary, Alberta, Canada
- Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
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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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8
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A panel of KSHV mutants in the polycistronic kaposin locus for precise analysis of individual protein products. J Virol 2021; 96:e0156021. [PMID: 34936820 PMCID: PMC8906436 DOI: 10.1128/jvi.01560-21] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Kaposi’s sarcoma-associated herpesvirus (KSHV) is the cause of several human cancers, including the endothelial cell (EC) malignancy, Kaposi’s sarcoma. Unique KSHV genes absent from other human herpesvirus genomes, the “K-genes,” are important for KSHV replication and pathogenesis. Among these, the kaposin transcript is highly expressed in all phases of infection, but its complex polycistronic nature has hindered functional analysis to date. At least three proteins are produced from the kaposin transcript: Kaposin A (KapA), B (KapB), and C (KapC). To determine the relative contributions of kaposin proteins during KSHV infection, we created a collection of mutant viruses unable to produce kaposin proteins individually or in combination. In previous work, we showed KapB alone recapitulated the elevated proinflammatory cytokine transcripts associated with KS via the disassembly of RNA granules called processing bodies (PBs). Using the new ΔKapB virus, we showed that KapB was necessary for this effect during latent KSHV infection. Moreover, we observed that despite the ability of all kaposin-deficient latent iSLK cell lines to produce virions, all displayed low viral episome copy number, a defect that became more pronounced after primary infection of naive ECs. For ΔKapB, provision of KapB in trans failed to complement the defect, suggesting a requirement for the kaposin locus in cis. These findings demonstrate that our panel of kaposin-deficient viruses enables precise analysis of the respective contributions of individual kaposin proteins to KSHV replication. Moreover, our mutagenesis approach serves as a guide for the functional analysis of other complex multicistronic viral loci. IMPORTANCE Kaposi’s sarcoma-associated herpesvirus (KSHV) expresses high levels of the kaposin transcript during both latent and lytic phases of replication. Due to its repetitive, GC-rich nature and polycistronic coding capacity, until now no reagents existed to permit a methodical analysis of the role of individual kaposin proteins in KSHV replication. We report the creation of a panel of recombinant viruses and matched producer cell lines that delete kaposin proteins individually or in combination. We demonstrate the utility of this panel by confirming the requirement of one kaposin translation product to a key KSHV latency phenotype. This study describes a new panel of molecular tools for the KSHV field to enable precise analysis of the roles of individual kaposin proteins during KSHV infection.
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Castle EL, Robinson CA, Douglas P, Rinker KD, Corcoran JA. Viral Manipulation of a Mechanoresponsive Signaling Axis Disassembles Processing Bodies. Mol Cell Biol 2021; 41:e0039921. [PMID: 34516278 PMCID: PMC8547432 DOI: 10.1128/mcb.00399-21] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 08/28/2021] [Accepted: 09/04/2021] [Indexed: 12/23/2022] Open
Abstract
Processing bodies (PBs) are ribonucleoprotein granules important for cytokine mRNA decay that are targeted for disassembly by many viruses. Kaposi's sarcoma-associated herpesvirus is the etiological agent of the inflammatory endothelial cancer, Kaposi's sarcoma, and a PB-regulating virus. The virus encodes kaposin B (KapB), which induces actin stress fibers (SFs) and cell spindling as well as PB disassembly. We now show that KapB-mediated PB disassembly requires actin rearrangements, RhoA effectors, and the mechanoresponsive transcription activator, YAP. Moreover, ectopic expression of active YAP or exposure of ECs to mechanical forces caused PB disassembly in the absence of KapB. We propose that the viral protein KapB activates a mechanoresponsive signaling axis and links changes in cell shape and cytoskeletal structures to enhanced inflammatory molecule expression using PB disassembly. Our work implies that cytoskeletal changes in other pathologies may similarly impact the inflammatory environment.
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Affiliation(s)
- Elizabeth L. Castle
- Department of Microbiology and Immunology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Carolyn-Ann Robinson
- Charbonneau Cancer Institute, University of Calgary, Calgary, Alberta, Canada
- Department of Microbiology, Immunology and Infectious Diseases, University of Calgary, Calgary, Alberta, Canada
| | - Pauline Douglas
- Department of Physiology and Pharmacology, University of Calgary, Calgary, Alberta, Canada
- Charbonneau Cancer Institute, University of Calgary, Calgary, Alberta, Canada
| | - Kristina D. Rinker
- Department of Physiology and Pharmacology, University of Calgary, Calgary, Alberta, Canada
- Department of Chemical and Petroleum Engineering and Centre for Bioengineering Research and Education, University of Calgary, Calgary, Alberta, Canada
- Charbonneau Cancer Institute, University of Calgary, Calgary, Alberta, Canada
| | - Jennifer A. Corcoran
- Department of Microbiology and Immunology, Dalhousie University, Halifax, Nova Scotia, Canada
- Charbonneau Cancer Institute, University of Calgary, Calgary, Alberta, Canada
- Department of Microbiology, Immunology and Infectious Diseases, University of Calgary, Calgary, Alberta, Canada
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10
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Ruan T, Zhang Y, Liu W, Li Y, Wang D, Du Z, Tao K, Wu C. Expression of DCP1a in gastric cancer and its biological function and mechanism in chemotherapy resistance in gastric cancer cells. Dig Liver Dis 2020; 52:1351-1358. [PMID: 32646734 DOI: 10.1016/j.dld.2020.06.031] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 06/17/2020] [Accepted: 06/19/2020] [Indexed: 12/11/2022]
Abstract
AIMS To detect the role of DCP1a in gastric cancer. To estimate the effect of DCP1a in gastric cancer cells on proliferation, invasion, migration and anti-drug behavior in vitro by down-regulating its expression. METHODS Using IHC staining and Western blot to check the expression of DCP1a in tissues and the cell lines. SGC7901 and BGC823 cells were transfected with DCP1a siRNA, and the expression of DCP1a protein and mRNA were detected. The cell proliferation rate was detected by MTT assay and plate cloning assay. Transwell assay was used to detect the change of cell metastasis. The inhibition rates of cells to chemotherapy were detected by MTT assay. And signal pathways were also detected. RESULTS The expression of DCP1a in cancer tissues is higher (p < 0.05), and higher expression of DCP1a is related to poor prognosis. After down-regulating the expression of DCP1a in cells, the proliferation rates, migration abilities and chemotherapy resistance decrease. We find that the expression of MRP-1 and the activation of AKT and STAT3 pathways might be involved in regulation. CONCLUSION The high expression of DCP1a might be associated with cancer development and prognosis. Down-regulating the expression of DCP1a will help to reduce chemotherapy resistance, which will help with further improvement of chemotherapy in gastric cancer.
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Affiliation(s)
- Tuo Ruan
- Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan 430022, Hubei, PR China
| | - Yazhi Zhang
- Department of Pediatrics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan 430022, Hubei, PR China
| | - Weizhen Liu
- Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan 430022, Hubei, PR China
| | - Yuan Li
- Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan 430022, Hubei, PR China
| | - Dianshi Wang
- Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan 430022, Hubei, PR China
| | - Zhouyuan Du
- Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan 430022, Hubei, PR China
| | - Kaixiong Tao
- Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan 430022, Hubei, PR China.
| | - Chuanqing Wu
- Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan 430022, Hubei, PR China.
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11
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Dolicka D, Sobolewski C, Gjorgjieva M, Correia de Sousa M, Berthou F, De Vito C, Colin DJ, Bejuy O, Fournier M, Maeder C, Blackshear PJ, Rubbia-Brandt L, Foti M. Tristetraprolin Promotes Hepatic Inflammation and Tumor Initiation but Restrains Cancer Progression to Malignancy. Cell Mol Gastroenterol Hepatol 2020; 11:597-621. [PMID: 32987153 PMCID: PMC7806869 DOI: 10.1016/j.jcmgh.2020.09.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 09/21/2020] [Accepted: 09/22/2020] [Indexed: 02/07/2023]
Abstract
BACKGROUND & AIMS Tristetraprolin (TTP) is a key post-transcriptional regulator of inflammatory and oncogenic transcripts. Accordingly, TTP was reported to act as a tumor suppressor in specific cancers. Herein, we investigated how TTP contributes to the development of liver inflammation and fibrosis, which are key drivers of hepatocarcinogenesis, as well as to the onset and progression of hepatocellular carcinoma (HCC). METHODS TTP expression was investigated in mouse/human models of hepatic metabolic diseases and cancer. The role of TTP in nonalcoholic steatohepatitis and HCC development was further examined through in vivo/vitro approaches using liver-specific TTP knockout mice and a panel of hepatic cancer cells. RESULTS Our data demonstrate that TTP loss in vivo strongly restrains development of hepatic steatosis and inflammation/fibrosis in mice fed a methionine/choline-deficient diet, as well as HCC development induced by the carcinogen diethylnitrosamine. In contrast, low TTP expression fostered migration and invasion capacities of in vitro transformed hepatic cancer cells likely by unleashing expression of key oncogenes previously associated with these cancerous features. Consistent with these data, TTP was significantly down-regulated in high-grade human HCC, a feature further correlating with poor clinical prognosis. Finally, we uncover hepatocyte nuclear factor 4 alpha and early growth response 1, two key transcription factors lost with hepatocyte dedifferentiation, as key regulators of TTP expression. CONCLUSIONS Although TTP importantly contributes to hepatic inflammation and cancer initiation, its loss with hepatocyte dedifferentiation fosters cancer cells migration and invasion. Loss of TTP may represent a clinically relevant biomarker of high-grade HCC associated with poor prognosis.
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MESH Headings
- Animals
- Carcinogenesis/genetics
- Carcinogenesis/immunology
- Carcinogenesis/pathology
- Carcinoma, Hepatocellular/genetics
- Carcinoma, Hepatocellular/immunology
- Carcinoma, Hepatocellular/mortality
- Carcinoma, Hepatocellular/pathology
- Cell Line, Tumor
- Datasets as Topic
- Diethylnitrosamine/administration & dosage
- Diethylnitrosamine/toxicity
- Down-Regulation
- Female
- Gene Expression Regulation, Neoplastic/immunology
- Hepatocytes
- Humans
- Liver/immunology
- Liver/pathology
- Liver Cirrhosis/genetics
- Liver Cirrhosis/immunology
- Liver Cirrhosis/pathology
- Liver Neoplasms/genetics
- Liver Neoplasms/immunology
- Liver Neoplasms/mortality
- Liver Neoplasms/pathology
- Liver Neoplasms, Experimental/chemistry
- Liver Neoplasms, Experimental/genetics
- Liver Neoplasms, Experimental/immunology
- Liver Neoplasms, Experimental/pathology
- Male
- Mice
- Non-alcoholic Fatty Liver Disease
- Primary Cell Culture
- Prognosis
- RNA-Seq
- Survival Analysis
- Tristetraprolin/genetics
- Tristetraprolin/metabolism
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Affiliation(s)
- Dobrochna Dolicka
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Cyril Sobolewski
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Monika Gjorgjieva
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Marta Correia de Sousa
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Flavien Berthou
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Claudio De Vito
- Division of Clinical Pathology, University Hospitals, Geneva, Switzerland
| | - Didier J Colin
- Centre for Biomedical Imaging and Preclinical Imaging Platform, University of Geneva, Geneva, Switzerland
| | - Olivia Bejuy
- Centre for Biomedical Imaging and Preclinical Imaging Platform, University of Geneva, Geneva, Switzerland
| | - Margot Fournier
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Christine Maeder
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Perry J Blackshear
- Laboratory of Signal Transduction, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina
| | | | - Michelangelo Foti
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, Geneva, Switzerland; Translational Research Centre in Onco-haematology, Faculty of Medicine, University of Geneva, Switzerland.
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12
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Legrand N, Dixon DA, Sobolewski C. Stress granules in colorectal cancer: Current knowledge and potential therapeutic applications. World J Gastroenterol 2020; 26:5223-5247. [PMID: 32994684 PMCID: PMC7504244 DOI: 10.3748/wjg.v26.i35.5223] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 08/12/2020] [Accepted: 09/03/2020] [Indexed: 02/06/2023] Open
Abstract
Stress granules (SGs) represent important non-membrane cytoplasmic compartments, involved in cellular adaptation to various stressful conditions (e.g., hypoxia, nutrient deprivation, oxidative stress). These granules contain several scaffold proteins and RNA-binding proteins, which bind to mRNAs and keep them translationally silent while protecting them from harmful conditions. Although the role of SGs in cancer development is still poorly known and vary between cancer types, increasing evidence indicate that the expression and/or the activity of several key SGs components are deregulated in colorectal tumors but also in pre-neoplastic conditions (e.g., inflammatory bowel disease), thus suggesting a potential role in the onset of colorectal cancer (CRC). It is therefore believed that SGs formation importantly contributes to various steps of colorectal tumorigenesis but also in chemoresistance. As CRC is the third most frequent cancer and one of the leading causes of cancer mortality worldwide, development of new therapeutic targets is needed to offset the development of chemoresistance and formation of metastasis. Abolishing SGs assembly may therefore represent an appealing therapeutic strategy to re-sensitize colon cancer cells to anti-cancer chemotherapies. In this review, we summarize the current knowledge on SGs in colorectal cancer and the potential therapeutic strategies that could be employed to target them.
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Affiliation(s)
- Noémie Legrand
- Department of Medicine, Faculty of Medicine, University of Geneva, Geneva CH-1211, Switzerland
| | - Dan A Dixon
- Department of Molecular Biosciences, University of Kansas, Lawrence, Kansas, and University of Kansas Cancer Center, Lawrence, KS 66045, United States
| | - Cyril Sobolewski
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, Geneva CH-1211, Switzerland
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13
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mRNA Post-Transcriptional Regulation by AU-Rich Element-Binding Proteins in Liver Inflammation and Cancer. Int J Mol Sci 2020; 21:ijms21186648. [PMID: 32932781 PMCID: PMC7554771 DOI: 10.3390/ijms21186648] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 09/09/2020] [Accepted: 09/09/2020] [Indexed: 12/12/2022] Open
Abstract
AU-rich element-binding proteins (AUBPs) represent important post-transcriptional regulators of gene expression. AUBPs can bind to the AU-rich elements present in the 3'-UTR of more than 8% of all mRNAs and are thereby able to control the stability and/or translation of numerous target mRNAs. The regulation of the stability and the translation of mRNA transcripts by AUBPs are highly complex processes that occur through multiple mechanisms depending on the cell type and the cellular context. While AUBPs have been shown to be involved in inflammatory processes and the development of various cancers, their important role and function in the development of chronic metabolic and inflammatory fatty liver diseases (FLDs), as well as in the progression of these disorders toward cancers such as hepatocellular carcinoma (HCC), has recently started to emerge. Alterations of either the expression or activity of AUBPs are indeed significantly associated with FLDs and HCC, and accumulating evidence indicates that several AUBPs are deeply involved in a significant number of cellular processes governing hepatic metabolic disorders, inflammation, fibrosis, and carcinogenesis. Herein, we discuss our current knowledge of the roles and functions of AUBPs in liver diseases and cancer. The relevance of AUBPs as potential biomarkers for different stages of FLD and HCC, or as therapeutic targets for these diseases, are also highlighted.
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14
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Legrand N, Dixon DA, Sobolewski C. AU-rich element-binding proteins in colorectal cancer. World J Gastrointest Oncol 2019; 11:71-90. [PMID: 30788036 PMCID: PMC6379757 DOI: 10.4251/wjgo.v11.i2.71] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Revised: 12/11/2018] [Accepted: 01/01/2019] [Indexed: 02/05/2023] Open
Abstract
Trans-acting factors controlling mRNA fate are critical for the post-transcriptional regulation of inflammation-related genes, as well as for oncogene and tumor suppressor expression in human cancers. Among them, a group of RNA-binding proteins called “Adenylate-Uridylate-rich elements binding proteins” (AUBPs) control mRNA stability or translation through their binding to AU-rich elements enriched in the 3’UTRs of inflammation- and cancer-associated mRNA transcripts. AUBPs play a central role in the recruitment of target mRNAs into small cytoplasmic foci called Processing-bodies and stress granules (also known as P-body/SG). Alterations in the expression and activities of AUBPs and P-body/SG assembly have been observed to occur with colorectal cancer (CRC) progression, indicating the significant role AUBP-dependent post-transcriptional regulation plays in controlling gene expression during CRC tumorigenesis. Accordingly, these alterations contribute to the pathological expression of many early-response genes involved in prostaglandin biosynthesis and inflammation, along with key oncogenic pathways. In this review, we summarize the current role of these proteins in CRC development. CRC remains a major cause of cancer mortality worldwide and, therefore, targeting these AUBPs to restore efficient post-transcriptional regulation of gene expression may represent an appealing therapeutic strategy.
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Affiliation(s)
- Noémie Legrand
- Department of Microbiology, Faculty of Medicine, University of Geneva, Geneva CH-1211, Switzerland
| | - Dan A Dixon
- Department of Molecular Biosciences, University of Kansas, Lawrence, Kansas, and University of Kansas Cancer Center, Kansas City, KS 66045, United States
| | - Cyril Sobolewski
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, Geneva CH-1211, Switzerland
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15
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Mikuda N, Kolesnichenko M, Beaudette P, Popp O, Uyar B, Sun W, Tufan AB, Perder B, Akalin A, Chen W, Mertins P, Dittmar G, Hinz M, Scheidereit C. The IκB kinase complex is a regulator of mRNA stability. EMBO J 2018; 37:embj.201798658. [PMID: 30467221 DOI: 10.15252/embj.201798658] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Revised: 10/01/2018] [Accepted: 10/08/2018] [Indexed: 12/16/2022] Open
Abstract
The IκB kinase (IKK) is considered to control gene expression primarily through activation of the transcription factor NF-κB. However, we show here that IKK additionally regulates gene expression on post-transcriptional level. IKK interacted with several mRNA-binding proteins, including a Processing (P) body scaffold protein, termed enhancer of decapping 4 (EDC4). IKK bound to and phosphorylated EDC4 in a stimulus-sensitive manner, leading to co-recruitment of P body components, mRNA decapping proteins 1a and 2 (DCP1a and DCP2) and to an increase in P body numbers. Using RNA sequencing, we identified scores of transcripts whose stability was regulated via the IKK-EDC4 axis. Strikingly, in the absence of stimulus, IKK-EDC4 promoted destabilization of pro-inflammatory cytokines and regulators of apoptosis. Our findings expand the reach of IKK beyond its canonical role as a regulator of transcription.
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Affiliation(s)
- Nadine Mikuda
- Signal Transduction Laboratory, Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - Marina Kolesnichenko
- Signal Transduction Laboratory, Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - Patrick Beaudette
- Mass Spectrometry Group, Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - Oliver Popp
- Mass Spectrometry Group, Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - Bora Uyar
- Bioinformatics/Mathematical Modelling Platform, Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - Wei Sun
- Laboratory for Functional Genomics and Systems Biology, Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - Ahmet Bugra Tufan
- Signal Transduction Laboratory, Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - Björn Perder
- Signal Transduction Laboratory, Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - Altuna Akalin
- Bioinformatics/Mathematical Modelling Platform, Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - Wei Chen
- Laboratory for Functional Genomics and Systems Biology, Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - Philipp Mertins
- Mass Spectrometry Group, Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - Gunnar Dittmar
- Mass Spectrometry Group, Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - Michael Hinz
- Signal Transduction Laboratory, Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - Claus Scheidereit
- Signal Transduction Laboratory, Max Delbrück Center for Molecular Medicine, Berlin, Germany
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16
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Roles of Tristetraprolin in Tumorigenesis. Int J Mol Sci 2018; 19:ijms19113384. [PMID: 30380668 PMCID: PMC6274954 DOI: 10.3390/ijms19113384] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Revised: 10/25/2018] [Accepted: 10/26/2018] [Indexed: 12/13/2022] Open
Abstract
Genetic loss or mutations in tumor suppressor genes promote tumorigenesis. The prospective tumor suppressor tristetraprolin (TTP) has been shown to negatively regulate tumorigenesis through destabilizing the messenger RNAs of critical genes implicated in both tumor onset and tumor progression. Regulation of TTP has therefore emerged as an important issue in tumorigenesis. Similar to other tumor suppressors, TTP expression is frequently downregualted in various human cancers, and its low expression is correlated with poor prognosis. Additionally, disruption in the regulation of TTP by various mechanisms results in the inactivation of TTP protein or altered TTP expression. A recent study showing alleviation of Myc-driven lymphomagenesis by the forced expression of TTP has shed light on new therapeutic avenues for cancer prevention and treatment through the restoration of TTP expression. In this review, we summarize key oncogenes subjected to the TTP-mediated mRNA degradation, and discuss how dysregulation of TTP can contribute to tumorigenesis. In addition, the control mechanism underlying TTP expression at the posttranscriptional and posttranslational levels will be discussed.
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17
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Park JY, Cho YL, Chae JR, Moon SH, Cho WG, Choi YJ, Lee SJ, Kang WJ. Gemcitabine-Incorporated G-Quadruplex Aptamer for Targeted Drug Delivery into Pancreas Cancer. MOLECULAR THERAPY. NUCLEIC ACIDS 2018; 12:543-553. [PMID: 30195790 PMCID: PMC6077122 DOI: 10.1016/j.omtn.2018.06.003] [Citation(s) in RCA: 61] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Revised: 06/11/2018] [Accepted: 06/11/2018] [Indexed: 01/07/2023]
Abstract
Gemcitabine has been considered a first-line chemotherapy agent for the treatment of pancreatic cancer. However, the initial response rate of gemcitabine is low and chemoresistance occurs frequently. Aptamers can be effectively internalized into cancer cells via binding to target molecules with high affinity and specificity. In the current study, we constructed an aptamer-based gemcitabine delivery system, APTA-12, and assessed its therapeutic effects on pancreatic cancer cells in vitro and in vivo. APTA-12 was effective in vitro and in vivo in pancreatic cancer cells with high expression of nucleolin. The results of in vitro cytotoxicity assays indicated that APTA-12 inhibited the growth of pancreatic cancer cell lines. In vivo evaluation showed that APTA-12 effectively inhibited the growth of pancreatic cancer in Capan-1 tumor-bearing mice compared to mice that received gemcitabine alone or vehicle. These results suggest that the gemcitabine-incorporated APTA-12 aptamer may be a promising targeted therapeutic strategy for pancreatic cancer.
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Affiliation(s)
- Jun Young Park
- Department of Nuclear Medicine, Severance Hospital, Yonsei University College of Medicine, Seoul, Korea; Department of Anatomy, Yonsei University Wonju College of Medicine, Wonju, Korea
| | - Ye Lim Cho
- Department of Nuclear Medicine, Severance Hospital, Yonsei University College of Medicine, Seoul, Korea
| | - Ju Ri Chae
- Department of Nuclear Medicine, Severance Hospital, Yonsei University College of Medicine, Seoul, Korea
| | | | - Won Gil Cho
- Department of Anatomy, Yonsei University Wonju College of Medicine, Wonju, Korea
| | - Yun Jung Choi
- Department of Radiology, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Korea
| | - Soo Jin Lee
- Aptabio Therapeutics Inc., Gyeonggi-do, Korea.
| | - Won Jun Kang
- Department of Nuclear Medicine, Severance Hospital, Yonsei University College of Medicine, Seoul, Korea.
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18
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Gillespie J, Ross RL, Corinaldesi C, Esteves F, Derrett-Smith E, McDermott MF, Doody GM, Denton CP, Emery P, Del Galdo F. Transforming Growth Factor β Activation Primes Canonical Wnt Signaling Through Down-Regulation of Axin-2. Arthritis Rheumatol 2018; 70:932-942. [PMID: 29409120 DOI: 10.1002/art.40437] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2016] [Accepted: 01/30/2018] [Indexed: 12/25/2022]
Abstract
OBJECTIVE Aberrant activation of Wnt signaling has been observed in tissues from patients with systemic sclerosis (SSc). This study aimed to determine the role of transforming growth factor β (TGFβ) in driving the increased Wnt signaling, through modulation of axis inhibition protein 2 (Axin-2), a critical regulator of the Wnt canonical pathway. METHODS Canonical Wnt signaling activation was analyzed by TOPflash T cell factor/lymphoid enhancer factor promoter assays. Axin-2 was evaluated in vitro by analysis of Axin-2 primary/mature transcript expression and decay, TGFβ receptor type I (TGFβRI) blockade, small interfering RNA-mediated depletion of tristetraprolin 1, and XAV-939-mediated Axin-2 stabilization. In vivo, Axin-2 messenger RNA (mRNA) and protein expression was determined in skin and lung biopsy samples from mice that express a kinase-deficient TGFβRII specifically on fibroblasts (TβRIIΔk-fib-transgenic mice) and from littermate controls. RESULTS SSc fibroblasts displayed an increased response to canonical Wnt ligands despite basal levels of Wnt signaling that were comparable to those in healthy control fibroblasts in vitro. Notably, we showed that SSc fibroblasts had reduced basal expression of Axin-2, which was caused by an endogenous TGFβ-dependent increase in Axin-2 mRNA decay. Accordingly, we observed that TGFβ decreased Axin-2 expression both in vitro in healthy control fibroblasts and in vivo in TβRIIΔk-fib-transgenic mice. Additionally, using Axin-2 gain- and loss-of-function experiments, we demonstrated that the TGFβ-induced increased response to Wnt activation characteristic of SSc fibroblasts depended on reduced bioavailability of Axin-2. CONCLUSION This study highlights the importance of reduced bioavailability of Axin-2 in mediating the increased canonical Wnt response observed in SSc fibroblasts. This novel mechanism extends our understanding of the processes involved in Wnt/β-catenin-driven pathology and supports the rationale for targeting the TGFβ pathway to regulate the aberrant Wnt signaling observed during fibrosis.
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Affiliation(s)
- Justin Gillespie
- University of Leeds and Leeds Teaching Hospitals NHS Trust, Leeds, UK
| | | | | | | | | | | | | | | | - Paul Emery
- University of Leeds and Leeds Teaching Hospitals NHS Trust, Leeds, UK
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19
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Qi MY, Song JW, Zhang Z, Huang S, Jing Q. P38 activation induces the dissociation of tristetraprolin from Argonaute 2 to increase ARE-mRNA stabilization. Mol Biol Cell 2018; 29:988-1002. [PMID: 29444957 PMCID: PMC5896936 DOI: 10.1091/mbc.e17-02-0105] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
ARE-mRNAs are actively degraded with tristetraprolin (TTP) in resting cells while they turn into stable messengers in activated cells. P38 plays a crucial role in stabilizing ARE-mRNA. Here we reveal that P38 activation represses the interaction between TTP and Ago2, thus restraining TTP from being targeted into processing bodies and stabilizing ARE-mRNA.
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Affiliation(s)
- Mei-Yan Qi
- Key Laboratory of Stem Cell Biology, Institute of Health Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Jing-Wen Song
- Department of Cardiology, Changhai Hospital, Shanghai 200433, China
| | - Zhuo Zhang
- Department of Cardiology, Changhai Hospital, Shanghai 200433, China.,Synthetic Biology and Biotechnology Laboratory, State Key Laboratory of Bioreactor Engineering, Shanghai Collaborative Innovation Center for Biomanufacturing Technology, East China University of Science and Technology, Shanghai 200237, China
| | - Shuang Huang
- Department of Cardiology, Changhai Hospital, Shanghai 200433, China
| | - Qing Jing
- Key Laboratory of Stem Cell Biology, Institute of Health Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China.,Department of Cardiology, Changhai Hospital, Shanghai 200433, China
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20
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Blanco FF, Preet R, Aguado A, Vishwakarma V, Stevens LE, Vyas A, Padhye S, Xu L, Weir SJ, Anant S, Meisner-Kober N, Brody JR, Dixon DA. Impact of HuR inhibition by the small molecule MS-444 on colorectal cancer cell tumorigenesis. Oncotarget 2018; 7:74043-74058. [PMID: 27677075 PMCID: PMC5342034 DOI: 10.18632/oncotarget.12189] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Accepted: 08/11/2016] [Indexed: 12/12/2022] Open
Abstract
Colorectal cancer (CRC) is the third most common cancer and a leading cause of cancer-related mortality. Observed during CRC tumorigenesis is loss of post-transcriptional regulation of tumor-promoting genes such as COX-2, TNFα and VEGF. Overexpression of the RNA-binding protein HuR (ELAVL1) occurs during colon tumorigenesis and is abnormally present within the cytoplasm, where it post-transcriptionally regulates genes through its interaction with 3′UTR AU-rich elements (AREs). Here, we examine the therapeutic potential of targeting HuR using MS-444, a small molecule HuR inhibitor. Treatment of CRC cells with MS-444 resulted in growth inhibition and increased apoptotic gene expression, while similar treatment doses in non-transformed intestinal cells had no appreciable effects. Mechanistically, MS-444 disrupted HuR cytoplasmic trafficking and released ARE-mRNAs for localization to P-bodies, but did not affect total HuR expression levels. This resulted in MS-444-mediated inhibition of COX-2 and other ARE-mRNA expression levels. Importantly, MS-444 was well tolerated and inhibited xenograft CRC tumor growth through enhanced apoptosis and decreased angiogenesis upon intraperitoneal administration. In vivo treatment of MS-444 inhibited HuR cytoplasmic localization and decreased COX-2 expression in tumors. These findings provide evidence that therapeutic strategies to target HuR in CRC warrant further investigation in an effort to move this approach to the clinic.
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Affiliation(s)
- Fernando F Blanco
- Department of Cancer Biology, University of Kansas Medical Center, Kansas City, KS, USA.,Department of Surgery, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, USA
| | - Ranjan Preet
- Department of Cancer Biology, University of Kansas Medical Center, Kansas City, KS, USA
| | - Andrea Aguado
- Department of Cancer Biology, University of Kansas Medical Center, Kansas City, KS, USA
| | - Vikalp Vishwakarma
- Department of Cancer Biology, University of Kansas Medical Center, Kansas City, KS, USA
| | - Laura E Stevens
- Department of Cancer Biology, University of Kansas Medical Center, Kansas City, KS, USA
| | - Alok Vyas
- Maharashtra Cosmopolitan Education Society's ISTRA, Azam Campus, University of Pune, India
| | - Subhash Padhye
- Maharashtra Cosmopolitan Education Society's ISTRA, Azam Campus, University of Pune, India
| | - Liang Xu
- University of Kansas Cancer Center, University of Kansas Medical Center, Kansas City, KS, USA.,Department of Molecular Biosciences, University of Kansas, Lawrence, KS, USA
| | - Scott J Weir
- Department of Pharmacology, University of Kansas Medical Center, Kansas City, KS, USA.,University of Kansas Cancer Center, University of Kansas Medical Center, Kansas City, KS, USA
| | - Shrikant Anant
- Department of Surgery, University of Kansas Medical Center, Kansas City, KS, USA.,University of Kansas Cancer Center, University of Kansas Medical Center, Kansas City, KS, USA
| | | | - Jonathan R Brody
- Department of Surgery, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, USA
| | - Dan A Dixon
- Department of Cancer Biology, University of Kansas Medical Center, Kansas City, KS, USA.,University of Kansas Cancer Center, University of Kansas Medical Center, Kansas City, KS, USA
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21
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Inflammation-regulated mRNA stability and the progression of vascular inflammatory diseases. Clin Sci (Lond) 2017; 131:2687-2699. [PMID: 29109302 DOI: 10.1042/cs20171373] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Revised: 10/09/2017] [Accepted: 10/10/2017] [Indexed: 12/22/2022]
Abstract
Cardiovascular disease remains a major medical and socioeconomic burden in developed and developing societies, and will increase with an aging and increasingly sedentary society. Vascular disease and atherosclerotic vascular syndromes are essentially inflammatory disorders, and transcriptional and post-transcriptional processes play essential roles in the ability of resident vascular and inflammatory cells to adapt to environmental stimuli. The regulation of mRNA translocation, stability, and translation are key processes of post-transcriptional regulation that permit these cells to rapidly respond to inflammatory stimuli. For the most part, these processes are controlled by elements in the 3'-UTR of labile, proinflammatory transcripts. Since proinflammatory transcripts almost exclusively contain AU-rich elements (AREs), this represents a tightly regulated and specific mechanism for initiation and maintenance of the proinflammatory phenotype. RNA-binding proteins (RBPs) recognize cis elements in 3'-UTR, and regulate each of these processes, but there is little literature exploring the concept that RBPs themselves can be directly regulated by inflammatory stimuli. Conceptually, inflammation-responsive RBPs represent an attractive target of rational therapies to combat vascular inflammatory syndromes. Herein we briefly describe the cellular and molecular etiology of atherosclerosis, and summarize our current understanding of RBPs and their specific roles in regulation of inflammatory mRNA stability. We also detail RBPs as targets of current anti-inflammatory modalities and how this may translate into better treatment for vascular inflammatory diseases.
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22
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Regulation of epithelial-mesenchymal transition and metastasis by TGF-β, P-bodies, and autophagy. Oncotarget 2017; 8:103302-103314. [PMID: 29262563 PMCID: PMC5732729 DOI: 10.18632/oncotarget.21871] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Accepted: 09/29/2017] [Indexed: 12/19/2022] Open
Abstract
Processing bodies (P-bodies) are ribonucleoprotein complexes involved in post-transcriptional mRNA metabolism that accumulate in cells exposed to various stress stimuli. The treatment of mammary epithelial cells with transforming growth factor-beta (TGF-β), triggers epithelial-mesenchymal transition (EMT), and induces the formation of P-bodies. Ectopic expression of the transcription factor TWIST, which stimulates EMT downstream of the TGF-β receptor, also promotes P-body formation. Removal of TGF-β from treated cells results in the clearance of P-bodies by a process that is blocked by inhibitors of autophagy. Activators of autophagy enhance P-body clearance and block EMT. Blockage of P-body formation by disruption of the gene for DDX6, a protein essential for P-body assembly, blocks EMT and prevents tumor cell metastasis in vivo. These studies suggest critical roles for P-body formation and autophagy in transitions of cancer cells between epithelial and mesenchymal phenotypes and help explain how autophagy functions to promote or suppress tumor cell growth during different stages of tumorigenesis.
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Muppala S, Xiao R, Krukovets I, Verbovetsky D, Yendamuri R, Habib N, Raman P, Plow E, Stenina-Adognravi O. Thrombospondin-4 mediates TGF-β-induced angiogenesis. Oncogene 2017; 36:5189-5198. [PMID: 28481870 PMCID: PMC5589494 DOI: 10.1038/onc.2017.140] [Citation(s) in RCA: 93] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Revised: 03/24/2017] [Accepted: 04/10/2017] [Indexed: 12/12/2022]
Abstract
TGF-β is a multifunctional cytokine affecting many cell types and implicated in tissue remodeling processes. Due to its many functions and cell-specific effects, the consequences of TGF-β signaling are process-and stage-dependent, and it is not uncommon that TGF-β exerts distinct and sometimes opposing effects on a disease progression depending on the stage and on the pathological changes associated with the stage. The mechanisms underlying cell- and process-specific effects of TGF-β are poorly understood. We are describing a novel pathway that mediates induction of angiogenesis in response to TGF-β1. We found that in endothelial cells (EC) TSP-4, a secreted extracellular matrix (ECM) protein is upregulated in response to TGF-β1 and mediates the effects of TGF-β1 on angiogenesis. Upregulation of TSP-4 does not require the synthesis of new protein, is not caused by decreased secretion of TSP-4, and is mediated by activation of SMAD3. Using Thbs4−/− mice and TSP-4 shRNA, we found that TSP-4 mediated pro-angiogenic functions on cultured EC and angiogenesis in vivo in response to TGF-β1. We observed ~ 3-fold increases in tumor mass and levels of angiogenesis markers in animals injected with TGF-β1, and these effects did not occur in Thbs4−/− animals. Injections of an inhibitor of TGF-β1 signaling SB431542 also decreased the weights of tumors and cancer angiogenesis. Our results from in vivo angiogenesis models and cultured EC document that TSP-4 mediates upregulation of angiogenesis by TGF-β1. Upregulation of pro-angiogenic TSP-4 and selective effects of TSP-4 on EC may contribute to stimulation of tumor growth by TGF-β despite the inhibition of cancer cell proliferation.
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Affiliation(s)
- S Muppala
- Department of Molecular Cardiology, Cleveland Clinic, Cleveland, OH, USA
| | - R Xiao
- Department of Molecular Cardiology, Cleveland Clinic, Cleveland, OH, USA
| | - I Krukovets
- Department of Molecular Cardiology, Cleveland Clinic, Cleveland, OH, USA
| | - D Verbovetsky
- Department of Molecular Cardiology, Cleveland Clinic, Cleveland, OH, USA
| | - R Yendamuri
- Department of Molecular Cardiology, Cleveland Clinic, Cleveland, OH, USA
| | - N Habib
- Department of Molecular Cardiology, Cleveland Clinic, Cleveland, OH, USA
| | - P Raman
- Department of Integrative Medical Sciences, North Ohio Medical University, Rootstown, OH, USA
| | - E Plow
- Department of Molecular Cardiology, Cleveland Clinic, Cleveland, OH, USA
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24
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Yoon NA, Jo HG, Lee UH, Park JH, Yoon JE, Ryu J, Kang SS, Min YJ, Ju SA, Seo EH, Huh IY, Lee BJ, Park JW, Cho WJ. Tristetraprolin suppresses the EMT through the down-regulation of Twist1 and Snail1 in cancer cells. Oncotarget 2017; 7:8931-43. [PMID: 26840564 PMCID: PMC4891015 DOI: 10.18632/oncotarget.7094] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Accepted: 01/17/2016] [Indexed: 12/31/2022] Open
Abstract
Inhibition of epithelial-mesenchymal transition (EMT)-inducing transcription factors Twist and Snail prevents tumor metastasis but enhances metastatic growth. Here, we report an unexpected role of a tumor suppressor tristetraprolin (TTP) in inhibiting Twist and Snail without enhancing cellular proliferation. TTP bound to the AU-rich element (ARE) within the mRNA 3′UTRs of Twist1 and Snail1, enhanced the decay of their mRNAs and inhibited the EMT of cancer cells. The ectopic expression of Twist1 or Snail1 without their 3′UTRs blocked the inhibitory effects of TTP on the EMT. We also observed that TTP overexpression suppressed the growth of cancer cells. Our data propose a new model whereby TTP down-regulates Twist1 and Snail1 and inhibits both the EMT and the proliferation of cancer cells.
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Affiliation(s)
- Nal Ae Yoon
- Department of Biological Sciences, University of Ulsan, Ulsan 680-749, Korea
| | - Hyun Gun Jo
- Department of Biological Sciences, University of Ulsan, Ulsan 680-749, Korea
| | - Unn Hwa Lee
- Department of Biological Sciences, University of Ulsan, Ulsan 680-749, Korea
| | - Ji Hye Park
- Department of Biological Sciences, University of Ulsan, Ulsan 680-749, Korea
| | - Ji Eun Yoon
- Department of Biological Sciences, University of Ulsan, Ulsan 680-749, Korea
| | - Jinhyun Ryu
- Department of Anatomy and Convergence Medical Science, Institute of Health Sciences, School of Medicine, Gyeongsang National University, Jinju, Gyeongnam 52727, Korea
| | - Sang Soo Kang
- Department of Anatomy and Convergence Medical Science, Institute of Health Sciences, School of Medicine, Gyeongsang National University, Jinju, Gyeongnam 52727, Korea
| | - Young Joo Min
- Department of Internal Medicine, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan 682-060, Korea
| | - Seong-A Ju
- Biomedical Research Center, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan 682-060, Korea
| | - Eun Hui Seo
- Department of Anesthesiology and Pain Medicine, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan 682-060, Korea
| | - In Young Huh
- Department of Anesthesiology and Pain Medicine, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan 682-060, Korea
| | - Byung Ju Lee
- Department of Biological Sciences, University of Ulsan, Ulsan 680-749, Korea
| | - Jeong Woo Park
- Department of Biological Sciences, University of Ulsan, Ulsan 680-749, Korea
| | - Wha Ja Cho
- Biomedical Research Center, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan 682-060, Korea
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25
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Sugi Y, Takahashi K, Kurihara K, Nakata K, Narabayashi H, Hamamoto Y, Suzuki M, Tsuda M, Hanazawa S, Hosono A, Kaminogawa S. Post-Transcriptional Regulation of Toll-Interacting Protein in the Intestinal Epithelium. PLoS One 2016; 11:e0164858. [PMID: 27741296 PMCID: PMC5065231 DOI: 10.1371/journal.pone.0164858] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Accepted: 10/03/2016] [Indexed: 02/06/2023] Open
Abstract
Immune responses against gut microbiota should be minimized to avoid unnecessary inflammation at mucosal surface. In this study, we analyzed the expression patterns of Toll-interacting protein (Tollip), an inhibitor of TLRs and IL-1 family cytokine-related intracellular signaling, in intestinal epithelial cells (IECs). Comparable mRNA expression was observed in murine small and large IECs (S-IECs and L-IECs). However, Tollip protein was only detected in L-IECs, but not in S-IECs. Similar results were obtained in germ-free mice, indicating that L-IEC-specific TOLLIP expression does not depend on bacterial colonization. Next, to understand the mechanisms underlying the post-transcriptional repression of Tollip, 3´-UTR-mediated translational regulation was evaluated. The region +1876/+2398 was responsible for the repression of Tollip expression. This region included the target sequence of miR-31. The inhibition of miR-31 restored the 3´-UTR-meditaed translational repression. In addition, miR-31 expression was significantly higher in S-IECs than in L-IECs, suggesting that miR-31 represses the translation of Tollip mRNA in S-IECs. Collectively, we conclude that the translation of Tollip is inhibited in S-IECs, at least in part, by miR-31 to yield L-IEC-specific high-level expression of the Tollip protein, which may contribute to the maintenance of intestinal homeostasis.
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Affiliation(s)
- Yutaka Sugi
- Department of Food Biochemistry and Biotechnology, College of Bioresource Sciences, Nihon University, Kanagawa, Japan
| | - Kyoko Takahashi
- Department of Food Biochemistry and Biotechnology, College of Bioresource Sciences, Nihon University, Kanagawa, Japan
- Department of Applied Biological Science, College of Bioresource Sciences, Nihon University, Kanagawa, Japan
- * E-mail:
| | - Kenta Kurihara
- Department of Food Biochemistry and Biotechnology, College of Bioresource Sciences, Nihon University, Kanagawa, Japan
| | - Kazuaki Nakata
- Department of Food Biochemistry and Biotechnology, College of Bioresource Sciences, Nihon University, Kanagawa, Japan
- Department of Applied Biological Science, College of Bioresource Sciences, Nihon University, Kanagawa, Japan
| | - Hikari Narabayashi
- Department of Applied Biological Science, College of Bioresource Sciences, Nihon University, Kanagawa, Japan
| | - Yuji Hamamoto
- Department of Food Biochemistry and Biotechnology, College of Bioresource Sciences, Nihon University, Kanagawa, Japan
| | - Makoto Suzuki
- Department of Food Biochemistry and Biotechnology, College of Bioresource Sciences, Nihon University, Kanagawa, Japan
| | - Masato Tsuda
- Department of Food Biochemistry and Biotechnology, College of Bioresource Sciences, Nihon University, Kanagawa, Japan
| | - Shigemasa Hanazawa
- Department of Applied Biological Science, College of Bioresource Sciences, Nihon University, Kanagawa, Japan
| | - Akira Hosono
- Department of Food Biochemistry and Biotechnology, College of Bioresource Sciences, Nihon University, Kanagawa, Japan
| | - Shuichi Kaminogawa
- Department of Food Biochemistry and Biotechnology, College of Bioresource Sciences, Nihon University, Kanagawa, Japan
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26
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Ganguly K, Giddaluru J, August A, Khan N. Post-transcriptional Regulation of Immunological Responses through Riboclustering. Front Immunol 2016; 7:161. [PMID: 27199986 PMCID: PMC4850162 DOI: 10.3389/fimmu.2016.00161] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2016] [Accepted: 04/15/2016] [Indexed: 12/22/2022] Open
Abstract
Immunological programing of immune cells varies in response to changing environmental signals. This process is facilitated by modifiers that regulate the translational fate of mRNAs encoding various immune mediators, including cytokines and chemokines, which in turn determine the rapid activation, tolerance, and plasticity of the immune system. RNA-binding proteins (RBPs) recruited by the specific sequence elements in mRNA transcripts are one such modifiers. These RBPs form RBP-RNA complexes known as "riboclusters." These riboclusters serve as RNA sorting machinery, where depending upon the composition of the ribocluster, translation, degradation, or storage of mRNA is controlled. Recent findings suggest that this regulation of mRNA homeostasis is critical for controlling the immune response. Here, we present the current knowledge of the ribocluster-mediated post-transcriptional regulation of immune mediators and highlight recent findings regarding their implications for the pathogenesis of acute or chronic inflammatory diseases.
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Affiliation(s)
- Koelina Ganguly
- Department of Biotechnology and Bioinformatics, School of Life Sciences, University of Hyderabad , Hyderabad , India
| | - Jeevan Giddaluru
- Department of Biotechnology and Bioinformatics, School of Life Sciences, University of Hyderabad , Hyderabad , India
| | - Avery August
- Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University , New York, NY , USA
| | - Nooruddin Khan
- Department of Biotechnology and Bioinformatics, School of Life Sciences, University of Hyderabad , Hyderabad , India
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27
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Johnson ME, Grassetti AV, Taroni JN, Lyons SM, Schweppe D, Gordon JK, Spiera RF, Lafyatis R, Anderson PJ, Gerber SA, Whitfield ML. Stress granules and RNA processing bodies are novel autoantibody targets in systemic sclerosis. Arthritis Res Ther 2016; 18:27. [PMID: 26801089 PMCID: PMC4724133 DOI: 10.1186/s13075-016-0914-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2015] [Accepted: 01/03/2016] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Autoantibody profiles represent important patient stratification markers in systemic sclerosis (SSc). Here, we performed serum-immunoprecipitations with patient antibodies followed by mass spectrometry (LC-MS/MS) to obtain an unbiased view of all possible autoantibody targets and their associated molecular complexes recognized by SSc. METHODS HeLa whole cell lysates were immunoprecipitated (IP) using sera of patients with SSc clinically positive for autoantibodies against RNA polymerase III (RNAP3), topoisomerase 1 (TOP1), and centromere proteins (CENP). IP eluates were then analyzed by LC-MS/MS to identify novel proteins and complexes targeted in SSc. Target proteins were examined using a functional interaction network to identify major macromolecular complexes, with direct targets validated by IP-Western blots and immunofluorescence. RESULTS A wide range of peptides were detected across patients in each clinical autoantibody group. Each group contained peptides representing a broad spectrum of proteins in large macromolecular complexes, with significant overlap between groups. Network analyses revealed significant enrichment for proteins in RNA processing bodies (PB) and cytosolic stress granules (SG) across all SSc subtypes, which were confirmed by both Western blot and immunofluorescence. CONCLUSIONS While strong reactivity was observed against major SSc autoantigens, such as RNAP3 and TOP1, there was overlap between groups with widespread reactivity seen against multiple proteins. Identification of PB and SG as major targets of the humoral immune response represents a novel SSc autoantigen and suggests a model in which a combination of chronic and acute cellular stresses result in aberrant cell death, leading to autoantibody generation directed against macromolecular nucleic acid-protein complexes.
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Affiliation(s)
- Michael E Johnson
- Department of Genetics, Geisel School of Medicine at Dartmouth, Hanover, NH, USA.
| | - Andrew V Grassetti
- Department of Genetics, Geisel School of Medicine at Dartmouth, Hanover, NH, USA.
| | - Jaclyn N Taroni
- Department of Genetics, Geisel School of Medicine at Dartmouth, Hanover, NH, USA.
| | - Shawn M Lyons
- Division of Rheumatology, Immunology, and Allergy, Brigham and Women's Hospital, Boston, MA, USA.
| | - Devin Schweppe
- Department of Genetics, Geisel School of Medicine at Dartmouth, Hanover, NH, USA.
| | - Jessica K Gordon
- Department of Rheumatology, Hospital for Special Surgery, New York, NY, USA.
| | - Robert F Spiera
- Department of Rheumatology, Hospital for Special Surgery, New York, NY, USA.
| | | | - Paul J Anderson
- Division of Rheumatology, Immunology, and Allergy, Brigham and Women's Hospital, Boston, MA, USA.
| | - Scott A Gerber
- Department of Genetics, Geisel School of Medicine at Dartmouth, Hanover, NH, USA.
| | - Michael L Whitfield
- Department of Genetics, Geisel School of Medicine at Dartmouth, Hanover, NH, USA.
- Dartmouth Medical School, Hinman Box 7400, Hanover, NH, 03755, USA.
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28
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Zheng XT, Xiao XQ, Dai JJ. Sodium butyrate down-regulates tristetraprolin-mediated cyclin B1 expression independent of the formation of processing bodies. Int J Biochem Cell Biol 2015; 69:241-8. [PMID: 26555753 DOI: 10.1016/j.biocel.2015.11.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Revised: 10/10/2015] [Accepted: 11/02/2015] [Indexed: 01/18/2023]
Abstract
Butyrate regulates multiple host cellular events including the cell cycle; however, little is known about the molecular mechanism by which butyrate induces a global down-regulation of the expression of genes associated with the cell cycle. Here, we demonstrate that treating HEK293T cells and the non-small-cell lung cancer cell line A549 with a high concentration of sodium butyrate reduces cyclin B1 expression. The underlying mechanism is related to the destabilization of its mRNA by tristetraprolin, which is up-regulated in response to sodium butyrate. Specifically, the sodium butyrate stimulation reduces the mRNA and protein expression of cyclin B1 and, conversely, upregulates tristetraprolin expression. Importantly, the overexpression of tristetraprolin in HEK293T decreases the mRNA and protein expression of cyclin B1; in contrast, knockdown of tristetraprolin mediated by small interfering RNA increases its expression in response to sodium butyrate treatment for both HEK293T and A549 cells. Furthermore, results from luciferase reporter assays and RNA immunoprecipitation indicate that sodium butyrate accelerates 3' UTR-dependent cyclin B1 decay by enhancing the binding of tristetraprolin to the 3' untranslated region of cyclin B1. Surprisingly, the overexpression of tristetraprolin prevents the formation of processing bodies, and the siRNA-mediated silencing of EDC4 does not restore the sodium butyrate-induced reduction of cyclin B1 expression. Thus, we confirm that NaBu regulates ZFP36-mediated cyclin B1 expression in a manner that is independent of the formation of P-bodies. The above findings disclose a novel mechanism of sodium butyrate-mediated gene expression regulation and might benefit its application in tumor treatment.
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Affiliation(s)
- Xiang-Tao Zheng
- Department of Vascular Surgery, the First Affiliated Hospital of Wenzhou Medical University, Wenzhou Medical University, Wenzhou, People's Republic of China
| | - Xiao-Qiang Xiao
- The Institute of Genomic Medicine, Wenzhou Medical University, Wenzhou, People's Republic of China.
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29
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Blanco FF, Jimbo M, Wulfkuhle J, Gallagher I, Deng J, Enyenihi L, Meisner-Kober N, Londin E, Rigoutsos I, Sawicki JA, Risbud MV, Witkiewicz AK, McCue PA, Jiang W, Rui H, Yeo CJ, Petricoin E, Winter JM, Brody JR. The mRNA-binding protein HuR promotes hypoxia-induced chemoresistance through posttranscriptional regulation of the proto-oncogene PIM1 in pancreatic cancer cells. Oncogene 2015; 35:2529-41. [PMID: 26387536 DOI: 10.1038/onc.2015.325] [Citation(s) in RCA: 89] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Revised: 07/08/2015] [Accepted: 07/10/2015] [Indexed: 12/15/2022]
Abstract
Previously, it has been shown that pancreatic ductal adenocarcinoma (PDA) tumors exhibit high levels of hypoxia, characterized by low oxygen pressure (pO2) and decreased O2 intracellular perfusion. Chronic hypoxia is strongly associated with resistance to cytotoxic chemotherapy and chemoradiation in an understudied phenomenon known as hypoxia-induced chemoresistance. The hypoxia-inducible, pro-oncogenic, serine-threonine kinase PIM1 (Proviral Integration site for Moloney murine leukemia virus 1) has emerged as a key regulator of hypoxia-induced chemoresistance in PDA and other cancers. Although its role in therapeutic resistance has been described previously, the molecular mechanism behind PIM1 overexpression in PDA is unknown. Here, we demonstrate that cis-acting AU-rich elements (ARE) present within a 38-base pair region of the PIM1 mRNA 3'-untranslated region mediate a regulatory interaction with the mRNA stability factor HuR (Hu antigen R) in the context of tumor hypoxia. Predominantly expressed in the nucleus in PDA cells, HuR translocates to the cytoplasm in response to hypoxic stress and stabilizes the PIM1 mRNA transcript, resulting in PIM1 protein overexpression. A reverse-phase protein array revealed that HuR-mediated regulation of PIM1 protects cells from hypoxic stress through phosphorylation and inactivation of the apoptotic effector BAD and activation of MEK1/2. Importantly, pharmacological inhibition of HuR by MS-444 inhibits HuR homodimerization and its cytoplasmic translocation, abrogates hypoxia-induced PIM1 overexpression and markedly enhances PDA cell sensitivity to oxaliplatin and 5-fluorouracil under physiologic low oxygen conditions. Taken together, these results support the notion that HuR has prosurvival properties in PDA cells by enabling them with growth advantages in stressful tumor microenvironment niches. Accordingly, these studies provide evidence that therapeutic disruption of HuR's regulation of PIM1 may be a key strategy in breaking an elusive chemotherapeutic resistance mechanism acquired by PDA cells that reside in hypoxic PDA microenvironments.
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Affiliation(s)
- F F Blanco
- Department of Pharmacology and Experimental Therapeutics, Division of Clinical Pharmacology, Thomas Jefferson University, Philadelphia, PA, USA.,Department of Surgery, Thomas Jefferson University, Philadelphia, PA, USA
| | - M Jimbo
- Department of Surgery, Thomas Jefferson University, Philadelphia, PA, USA
| | - J Wulfkuhle
- Center for Applied Proteomics and Molecular Medicine, School of Systems Biology, George Mason University, Manassas, VA, USA
| | - I Gallagher
- Center for Applied Proteomics and Molecular Medicine, School of Systems Biology, George Mason University, Manassas, VA, USA
| | - J Deng
- Center for Applied Proteomics and Molecular Medicine, School of Systems Biology, George Mason University, Manassas, VA, USA
| | - L Enyenihi
- Department of Surgery, Thomas Jefferson University, Philadelphia, PA, USA
| | - N Meisner-Kober
- Novartis Institutes for Biomedical Research, Novartis, Switzerland
| | - E Londin
- Center for Computational Medicine, Thomas Jefferson University, Philadelphia, PA, USA
| | - I Rigoutsos
- Center for Computational Medicine, Thomas Jefferson University, Philadelphia, PA, USA
| | - J A Sawicki
- Lankenau Institute for Medical Research, Philadelphia, PA, USA
| | - M V Risbud
- Department of Orthopedic Surgery, Thomas Jefferson University, Philadelphia, PA, USA
| | - A K Witkiewicz
- Department of Pathology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - P A McCue
- Department of Pathology, Thomas Jefferson University, Philadelphia, PA, USA
| | - W Jiang
- Department of Pathology, Thomas Jefferson University, Philadelphia, PA, USA
| | - H Rui
- Department of Cancer Biology, Thomas Jefferson University, Philadelphia, PA, USA
| | - C J Yeo
- Department of Surgery, Thomas Jefferson University, Philadelphia, PA, USA
| | - E Petricoin
- Center for Applied Proteomics and Molecular Medicine, School of Systems Biology, George Mason University, Manassas, VA, USA
| | - J M Winter
- Department of Surgery, Thomas Jefferson University, Philadelphia, PA, USA
| | - J R Brody
- Department of Surgery, Thomas Jefferson University, Philadelphia, PA, USA
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30
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Protein synthesis as an integral quality control mechanism during ageing. Ageing Res Rev 2015; 23:75-89. [PMID: 25555680 DOI: 10.1016/j.arr.2014.12.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2014] [Revised: 12/18/2014] [Accepted: 12/22/2014] [Indexed: 01/17/2023]
Abstract
Ageing is manifested as functional and structural deterioration that affects cell and tissue physiology. mRNA translation is a central cellular process, supplying cells with newly synthesized proteins. Accumulating evidence suggests that alterations in protein synthesis are not merely a corollary but rather a critical factor for the progression of ageing. Here, we survey protein synthesis regulatory mechanisms and focus on the pre-translational regulation of the process exerted by non-coding RNA species, RNA binding proteins and alterations of intrinsic RNA properties. In addition, we discuss the tight relationship between mRNA translation and two central pathways that modulate ageing, namely the insulin/IGF-1 and TOR signalling cascades. A thorough understanding of the complex interplay between protein synthesis regulation and ageing will provide critical insights into the pathogenesis of age-related disorders, associated with impaired proteostasis and protein quality control.
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31
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Sobolewski C, Sanduja S, Blanco FF, Hu L, Dixon DA. Histone Deacetylase Inhibitors Activate Tristetraprolin Expression through Induction of Early Growth Response Protein 1 (EGR1) in Colorectal Cancer Cells. Biomolecules 2015; 5:2035-55. [PMID: 26343742 PMCID: PMC4598787 DOI: 10.3390/biom5032035] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2015] [Revised: 07/30/2015] [Accepted: 08/10/2015] [Indexed: 02/06/2023] Open
Abstract
The RNA-binding protein tristetraprolin (TTP) promotes rapid decay of mRNAs bearing 3' UTR AU-rich elements (ARE). In many cancer types, loss of TTP expression is observed allowing for stabilization of ARE-mRNAs and their pathologic overexpression. Here we demonstrate that histone deacetylase (HDAC) inhibitors (Trichostatin A, SAHA and sodium butyrate) promote TTP expression in colorectal cancer cells (HCA-7, HCT-116, Moser and SW480 cells) and cervix carcinoma cells (HeLa). We found that HDAC inhibitors-induced TTP expression, promote the decay of COX-2 mRNA, and inhibit cancer cell proliferation. HDAC inhibitors were found to promote TTP transcription through activation of the transcription factor Early Growth Response protein 1 (EGR1). Altogether, our findings indicate that loss of TTP in tumors occurs through silencing of EGR1 and suggests a therapeutic approach to rescue TTP expression in colorectal cancer.
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Affiliation(s)
- Cyril Sobolewski
- Department of Cancer Biology, University of Kansas Medical Center, Kansas City, KS 66160, USA.
| | - Sandhya Sanduja
- Department of Cancer Biology, University of Kansas Medical Center, Kansas City, KS 66160, USA.
| | - Fernando F Blanco
- Department of Cancer Biology, University of Kansas Medical Center, Kansas City, KS 66160, USA.
| | - Liangyan Hu
- Department of Cancer Biology, University of Kansas Medical Center, Kansas City, KS 66160, USA.
| | - Dan A Dixon
- Department of Cancer Biology, University of Kansas Medical Center, Kansas City, KS 66160, USA.
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32
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Urbanek MO, Galka-Marciniak P, Olejniczak M, Krzyzosiak WJ. RNA imaging in living cells - methods and applications. RNA Biol 2015; 11:1083-95. [PMID: 25483044 PMCID: PMC4615301 DOI: 10.4161/rna.35506] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Numerous types of transcripts perform multiple functions in cells, and these functions are mainly facilitated by the interactions of the RNA with various proteins and other RNAs. Insight into the dynamics of RNA biosynthesis, processing and cellular activities is highly desirable because this knowledge will deepen our understanding of cell physiology and help explain the mechanisms of RNA-mediated pathologies. In this review, we discuss the live RNA imaging systems that have been developed to date. We highlight information on the design of these systems, briefly discuss their advantages and limitations and provide examples of their numerous applications in various organisms and cell types. We present a detailed examination of one application of RNA imaging systems: this application aims to explain the role of mutant transcripts in human disease pathogenesis caused by triplet repeat expansions. Thus, this review introduces live RNA imaging systems and provides a glimpse into their various applications.
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Affiliation(s)
- Martyna O Urbanek
- a Department of Molecular Biomedicine; Institute of Bioorganic Chemistry; Polish Academy of Sciences ; Poznan , Poland
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33
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Ma Y, Li W, Yin Y, Li W. AST IV inhibits H₂O₂-induced human umbilical vein endothelial cell apoptosis by suppressing Nox4 expression through the TGF-β1/Smad2 pathway. Int J Mol Med 2015; 35:1667-74. [PMID: 25891879 DOI: 10.3892/ijmm.2015.2188] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2014] [Accepted: 04/08/2015] [Indexed: 11/06/2022] Open
Abstract
Endothelial cell apoptosis plays an important role in the pathophysiological mechanisms of vascular complications in diabetes mellitus (DM). NADPH oxidase 4 (Nox4)-dependent reactive oxygen species (ROS) aggregation is the main cause of vascular endothelial cell apoptosis. The transforming growth factor-β1 (TGF-β1)/Smad2 signaling pathway is involved in the apoptosis of several types of cells. However, the association between vascular endothelial cell apoptosis and Nox4, and the involvement of the TGF-β1/Smad2 signaling pathway in vascular endothelial cell apoptosis remain unclear. In the present study, we aimed to investigate the role of Nox4-dependent ROS production and to determine the involvement of the TGF-β1/Smad2 signaling pathway in endothelial cell apoptosis induced by oxidative stress which causes vascular injury in DM. We demonstrated that hydrogen peroxide (H2O2) increased Nox4-dependent-ROS aggregation, as well as the expression of TGF-β1, Smad2, Bax and caspase-3, decreased Bcl-2 expression and increased the apoptosis of human umbilical vein endothelial cells (HUVECs). Treatment with diphenyliodonium (DPI), a specific inhibitor of Nox4 or astragaloside IV (AST IV), a monomer located in an extract of astragaloside, decreased Nox4 expression and the levels of ROS, decreased TGF-β1 and Smad2 expression, altered the expression of apoptosis-related genes and decreased the apoptosis of HUVECs. Treatment with LY2109761, a selective inhibitor of the TGF-β1/Smad2 pathway, produced results similar to those of DPI; however, LY2109761 had no effect on Nox4 expression and ROS levels. Taken together, the findings of the present study suggest that H2O2 contributes to HUVEC apoptosis by inducing Nox4-dependent ROS aggregation and activating the TGF-β1/Smad2 signaling pathway. Our data indicate that the protective effects of AST IV against vascular endothelial cell apoptosis in DM are mainly associated with the decrease in Nox4 expression through the TGF-β1/Smad2 signaling pathway. Furthermore, the inhibition of the activation of the TGF-β1/Smad2 signaling pathway may be another potential therapeutic strategy in the treatment of DM.
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Affiliation(s)
- Yuhong Ma
- Department of Pharmacology, College of Basic Medicine, Anhui Medical University, Hefei, Anhui 230032, P.R. China
| | - Weizu Li
- Department of Pharmacology, College of Basic Medicine, Anhui Medical University, Hefei, Anhui 230032, P.R. China
| | - Yanyan Yin
- Department of Pharmacology, College of Basic Medicine, Anhui Medical University, Hefei, Anhui 230032, P.R. China
| | - Weiping Li
- Department of Pharmacology, College of Basic Medicine, Anhui Medical University, Hefei, Anhui 230032, P.R. China
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Pérez-Vilaró G, Fernández-Carrillo C, Mensa L, Miquel R, Sanjuan X, Forns X, Pérez-del-Pulgar S, Díez J. Hepatitis C virus infection inhibits P-body granule formation in human livers. J Hepatol 2015; 62:785-90. [PMID: 25463546 DOI: 10.1016/j.jhep.2014.11.018] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/22/2014] [Revised: 10/28/2014] [Accepted: 11/06/2014] [Indexed: 12/04/2022]
Abstract
BACKGROUND & AIMS Decoding the myriad of interactions that hepatitis C virus (HCV) establishes with infected cells is mandatory to obtain a complete understanding of HCV biology and its associated pathogenesis. We and others have previously found that HCV infection disrupts the formation of P-bodies in cell culture. These are cytoplasmic RNA granules with key roles in post-transcriptional regulation of gene expression. Therefore, P-body disruption might have consequences beyond viral propagation. However, whether P-body disruption occurs also in vivo is unknown. Aim of this study was to address this important issue. METHODS Formalin-fixed paraffin-embedded liver biopsies from four groups of patients (healthy donors, patients with non-virus related liver inflammation, HCV- and HBV-infected patients) were immunostained to detect DDX6 and Dcp1, two core P-body components. Changes in the localization of these proteins were assessed by confocal microscopy. RESULTS HCV specifically inhibited P-body formation in hepatocytes from human livers regardless of viral genotype, inflammation grade or whether the infection was recent or long established. Importantly, this alteration was reversed once HCV was eliminated by therapy. Furthermore, we observed in vivo an unexpected heterogeneity in P-body composition, which might reflect functional specializations. CONCLUSIONS This is the first comprehensive in vivo P-body analysis that links a pathogenic condition to P-body alterations. Because of their role in gene expression, the alteration of P-bodies should be further studied to understand fully complex HCV-associated pathologies.
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Affiliation(s)
| | | | - Laura Mensa
- Liver Unit, Hospital Clínic, IDIBAPS, CIBERehd, Barcelona, Spain
| | - Rosa Miquel
- Pathology Department, Hospital Clínic, Barcelona, Spain
| | - Xavier Sanjuan
- Scientific and Technical Services, Universitat Pompeu Fabra, Barcelona, Spain; Advanced Light Microscopy Unit, Center for Genomic Regulation, Barcelona, Spain
| | - Xavier Forns
- Liver Unit, Hospital Clínic, IDIBAPS, CIBERehd, Barcelona, Spain
| | | | - Juana Díez
- Molecular Virology, Universitat Pompeu Fabra, Barcelona, Spain.
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Kafasla P, Skliris A, Kontoyiannis DL. Post-transcriptional coordination of immunological responses by RNA-binding proteins. Nat Immunol 2014; 15:492-502. [PMID: 24840980 DOI: 10.1038/ni.2884] [Citation(s) in RCA: 151] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2014] [Accepted: 04/01/2014] [Indexed: 12/22/2022]
Abstract
Immunological reactions are propelled by ever-changing signals that alter the translational ability of the RNA in the cells involved. Such alterations are considered to be consequential modifications in the transcriptomic decoding of the genetic blueprint. The identification of RNA-binding protein (RBP) assemblies engaged in the coordinative regulation of state-specific RNAs indicates alternative and exclusive means for determining the activation, plasticity and tolerance of cells of the immune system. Here we review current knowledge about RBP-regulated post-transcriptional events involved in the reactivity of cells of the immune system and the importance of their alteration during chronic inflammatory pathology and autoimmunity.
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Affiliation(s)
- Panagiota Kafasla
- Division of Immunology, Biomedical Sciences Research Center "Alexander Fleming", Vari, Greece
| | - Antonis Skliris
- Division of Immunology, Biomedical Sciences Research Center "Alexander Fleming", Vari, Greece
| | - Dimitris L Kontoyiannis
- Division of Immunology, Biomedical Sciences Research Center "Alexander Fleming", Vari, Greece
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