51
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Chen M, Asanuma M, Takahashi M, Shichino Y, Mito M, Fujiwara K, Saito H, Floor SN, Ingolia NT, Sodeoka M, Dodo K, Ito T, Iwasaki S. Dual targeting of DDX3 and eIF4A by the translation inhibitor rocaglamide A. Cell Chem Biol 2021; 28:475-486.e8. [PMID: 33296667 PMCID: PMC8052261 DOI: 10.1016/j.chembiol.2020.11.008] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Revised: 11/04/2020] [Accepted: 11/17/2020] [Indexed: 12/12/2022]
Abstract
The translation inhibitor rocaglamide A (RocA) has shown promising antitumor activity because it uniquely clamps eukaryotic initiation factor (eIF) 4A onto polypurine RNA for selective translational repression. As eIF4A has been speculated to be a unique target of RocA, alternative targets have not been investigated. Here, we reveal that DDX3 is another molecular target of RocA. Proximity-specific fluorescence labeling of an O-nitrobenzoxadiazole-conjugated derivative revealed that RocA binds to DDX3. RocA clamps the DDX3 protein onto polypurine RNA in an ATP-independent manner. Analysis of a de novo-assembled transcriptome from the plant Aglaia, a natural source of RocA, uncovered the amino acid critical for RocA binding. Moreover, ribosome profiling showed that because of the dominant-negative effect of RocA, high expression of eIF4A and DDX3 strengthens translational repression in cancer cells. This study indicates that sequence-selective clamping of DDX3 and eIF4A, and subsequent dominant-negative translational repression by RocA determine its tumor toxicity.
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Affiliation(s)
- Mingming Chen
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Chiba 277-8561, Japan; RNA Systems Biochemistry Laboratory, RIKEN Cluster for Pioneering Research, Wako, Saitama 351-0198, Japan
| | - Miwako Asanuma
- RIKEN Center for Sustainable Resource Science, Wako, Saitama 351-0198, Japan; Synthetic Organic Chemistry Laboratory, RIKEN Cluster for Pioneering Research, Wako, Saitama 351-0198, Japan
| | - Mari Takahashi
- Laboratory for Translation Structural Biology, RIKEN Center for Biosystems Dynamics Research, Tsurumi-ku, Yokohama 230-0045, Japan
| | - Yuichi Shichino
- RNA Systems Biochemistry Laboratory, RIKEN Cluster for Pioneering Research, Wako, Saitama 351-0198, Japan
| | - Mari Mito
- RNA Systems Biochemistry Laboratory, RIKEN Cluster for Pioneering Research, Wako, Saitama 351-0198, Japan
| | - Koichi Fujiwara
- Synthetic Organic Chemistry Laboratory, RIKEN Cluster for Pioneering Research, Wako, Saitama 351-0198, Japan
| | - Hironori Saito
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Chiba 277-8561, Japan; RNA Systems Biochemistry Laboratory, RIKEN Cluster for Pioneering Research, Wako, Saitama 351-0198, Japan
| | - Stephen N Floor
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA; Department of Cell and Tissue Biology, University of California, San Francisco, CA 94143, USA; Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, CA 94143, USA
| | - Nicholas T Ingolia
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA
| | - Mikiko Sodeoka
- RIKEN Center for Sustainable Resource Science, Wako, Saitama 351-0198, Japan; Synthetic Organic Chemistry Laboratory, RIKEN Cluster for Pioneering Research, Wako, Saitama 351-0198, Japan; AMED-CREST, Japan Agency for Medical Research and Development, Japan
| | - Kosuke Dodo
- RIKEN Center for Sustainable Resource Science, Wako, Saitama 351-0198, Japan; Synthetic Organic Chemistry Laboratory, RIKEN Cluster for Pioneering Research, Wako, Saitama 351-0198, Japan; AMED-CREST, Japan Agency for Medical Research and Development, Japan
| | - Takuhiro Ito
- Laboratory for Translation Structural Biology, RIKEN Center for Biosystems Dynamics Research, Tsurumi-ku, Yokohama 230-0045, Japan; AMED-CREST, Japan Agency for Medical Research and Development, Japan
| | - Shintaro Iwasaki
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Chiba 277-8561, Japan; RNA Systems Biochemistry Laboratory, RIKEN Cluster for Pioneering Research, Wako, Saitama 351-0198, Japan; AMED-CREST, Japan Agency for Medical Research and Development, Japan.
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52
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Singh K, Lin J, Lecomte N, Mohan P, Gokce A, Sanghvi VR, Jiang M, Grbovic-Huezo O, Burčul A, Stark SG, Romesser PB, Chang Q, Melchor JP, Beyer RK, Duggan M, Fukase Y, Yang G, Ouerfelli O, Viale A, de Stanchina E, Stamford AW, Meinke PT, Rätsch G, Leach SD, Ouyang Z, Wendel HG. Targeting eIF4A-Dependent Translation of KRAS Signaling Molecules. Cancer Res 2021; 81:2002-2014. [PMID: 33632898 PMCID: PMC8137674 DOI: 10.1158/0008-5472.can-20-2929] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2020] [Revised: 12/01/2020] [Accepted: 02/22/2021] [Indexed: 11/16/2022]
Abstract
Pancreatic adenocarcinoma (PDAC) epitomizes a deadly cancer driven by abnormal KRAS signaling. Here, we show that the eIF4A RNA helicase is required for translation of key KRAS signaling molecules and that pharmacological inhibition of eIF4A has single-agent activity against murine and human PDAC models at safe dose levels. EIF4A was uniquely required for the translation of mRNAs with long and highly structured 5' untranslated regions, including those with multiple G-quadruplex elements. Computational analyses identified these features in mRNAs encoding KRAS and key downstream molecules. Transcriptome-scale ribosome footprinting accurately identified eIF4A-dependent mRNAs in PDAC, including critical KRAS signaling molecules such as PI3K, RALA, RAC2, MET, MYC, and YAP1. These findings contrast with a recent study that relied on an older method, polysome fractionation, and implicated redox-related genes as eIF4A clients. Together, our findings highlight the power of ribosome footprinting in conjunction with deep RNA sequencing in accurately decoding translational control mechanisms and define the therapeutic mechanism of eIF4A inhibitors in PDAC. SIGNIFICANCE: These findings document the coordinate, eIF4A-dependent translation of RAS-related oncogenic signaling molecules and demonstrate therapeutic efficacy of eIF4A blockade in pancreatic adenocarcinoma.
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Affiliation(s)
- Kamini Singh
- Cancer Biology and Genetics Program, Memorial Sloan-Kettering Cancer Center, New York, New York
| | - Jianan Lin
- The Jackson Laboratory for Genomic Medicine, Farmington, Connecticut
- Department of Biomedical Engineering, University of Connecticut, Storrs, Connecticut
| | - Nicolas Lecomte
- David M. Rubenstein Center for Pancreatic Cancer Research, Memorial Sloan-Kettering Cancer Center, New York, New York
| | - Prathibha Mohan
- Cancer Biology and Genetics Program, Memorial Sloan-Kettering Cancer Center, New York, New York
| | - Askan Gokce
- David M. Rubenstein Center for Pancreatic Cancer Research, Memorial Sloan-Kettering Cancer Center, New York, New York
| | - Viraj R Sanghvi
- Cancer Biology and Genetics Program, Memorial Sloan-Kettering Cancer Center, New York, New York
- Department of Molecular and Cellular Pharmacology, Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, Florida
| | - Man Jiang
- Cancer Biology and Genetics Program, Memorial Sloan-Kettering Cancer Center, New York, New York
| | - Olivera Grbovic-Huezo
- Cancer Biology and Genetics Program, Memorial Sloan-Kettering Cancer Center, New York, New York
| | - Antonija Burčul
- Computational Biology Department, Memorial Sloan-Kettering Cancer Center, New York, New York
| | - Stefan G Stark
- Computational Biology Department, Memorial Sloan-Kettering Cancer Center, New York, New York
- Department of Computer Science, Biomedical Informatics, ETH, Zürich, Zürich, Switzerland
| | - Paul B Romesser
- Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York
| | - Qing Chang
- Molecular Pharmacology Program, Memorial Sloan-Kettering Cancer Center, New York, New York
| | - Jerry P Melchor
- David M. Rubenstein Center for Pancreatic Cancer Research, Memorial Sloan-Kettering Cancer Center, New York, New York
| | - Rachel K Beyer
- Cancer Research Technology Program, Frederick National Laboratory for Cancer Research, Frederick, Maryland
| | - Mark Duggan
- Tri-Institutional Drug Development Initiative, Memorial Sloan-Kettering Cancer Center, New York, New York
| | - Yoshiyuki Fukase
- Tri-Institutional Drug Development Initiative, Memorial Sloan-Kettering Cancer Center, New York, New York
| | - Guangli Yang
- The Organic Synthesis Core Facility, Memorial Sloan-Kettering Cancer Center, New York, New York
| | - Ouathek Ouerfelli
- The Organic Synthesis Core Facility, Memorial Sloan-Kettering Cancer Center, New York, New York
| | - Agnes Viale
- Integrated Genomics Operation, Center for Molecular Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York
| | - Elisa de Stanchina
- Molecular Pharmacology Program, Memorial Sloan-Kettering Cancer Center, New York, New York
| | - Andrew W Stamford
- Tri-Institutional Drug Development Initiative, Memorial Sloan-Kettering Cancer Center, New York, New York
| | - Peter T Meinke
- Tri-Institutional Drug Development Initiative, Memorial Sloan-Kettering Cancer Center, New York, New York
| | - Gunnar Rätsch
- Computational Biology Department, Memorial Sloan-Kettering Cancer Center, New York, New York
- Department of Computer Science, Biomedical Informatics, ETH, Zürich, Zürich, Switzerland
| | - Steven D Leach
- Molecular Systems Biology and Surgery, Geisel School of Medicine, Dartmouth, Norris Cotton Cancer Center at Dartmouth-Hitchcock, Lebanon, New Hampshire
| | - Zhengqing Ouyang
- Department of Biostatistics and Epidemiology, School of Public Health and Health Sciences, University of Massachusetts, Amherst, Massachusetts
| | - Hans-Guido Wendel
- Cancer Biology and Genetics Program, Memorial Sloan-Kettering Cancer Center, New York, New York.
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Chu J, Zhang W, Cencic R, O'Connor PBF, Robert F, Devine WG, Selznick A, Henkel T, Merrick WC, Brown LE, Baranov PV, Porco JA, Pelletier J. Rocaglates Induce Gain-of-Function Alterations to eIF4A and eIF4F. Cell Rep 2021; 30:2481-2488.e5. [PMID: 32101697 PMCID: PMC7077502 DOI: 10.1016/j.celrep.2020.02.002] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Revised: 12/13/2019] [Accepted: 01/31/2020] [Indexed: 12/31/2022] Open
Abstract
Rocaglates are a diverse family of biologically active molecules that have gained tremendous interest in recent years due to their promising activities in pre-clinical cancer studies. As a result, this family of compounds has been significantly expanded through the development of efficient synthetic schemes. However, it is unknown whether all of the members of the rocaglate family act through similar mechanisms of action. Here, we present a comprehensive study comparing the biological activities of >200 rocaglates to better understand how the presence of different chemical entities influences their biological activities. Through this, we find that most rocaglates preferentially repress the translation of mRNAs containing purine-rich 5′ leaders, but certain rocaglates lack this bias in translation repression. We also uncover an aspect of rocaglate mechanism of action in which the pool of translationally active eIF4F is diminished due to the sequestration of the complex onto RNA. Rocaglates are a diverse family of small molecules that inhibit eIF4A. Chu et al. undertake a comparative analysis of the bioactivity of >200 rocaglates and uncover nuances in their mechanisms of action. Rocaglates interfere with eIF4F release from the cap and exert a bystander effect to inhibit translation.
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Affiliation(s)
- Jennifer Chu
- Department of Biochemistry, McGill University, Montreal, QC, Canada
| | - Wenhan Zhang
- Department of Chemistry and Center for Molecular Discovery (BU-CMD), Boston University, Boston, MA, USA
| | - Regina Cencic
- Department of Biochemistry, McGill University, Montreal, QC, Canada
| | | | - Francis Robert
- Department of Biochemistry, McGill University, Montreal, QC, Canada
| | - William G Devine
- Department of Chemistry and Center for Molecular Discovery (BU-CMD), Boston University, Boston, MA, USA
| | - Asher Selznick
- Department of Biochemistry, McGill University, Montreal, QC, Canada
| | | | - William C Merrick
- Department of Biochemistry, School of Medicine, Case Western Reserve University, Cleveland, OH 44106-4935, USA
| | - Lauren E Brown
- Department of Chemistry and Center for Molecular Discovery (BU-CMD), Boston University, Boston, MA, USA
| | - Pavel V Baranov
- School of Biochemistry and Cell Biology, University College Cork, Cork, Ireland; Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry RAS, Moscow, Russia
| | - John A Porco
- Department of Chemistry and Center for Molecular Discovery (BU-CMD), Boston University, Boston, MA, USA.
| | - Jerry Pelletier
- Department of Biochemistry, McGill University, Montreal, QC, Canada; Department of Oncology, McGill University, Montreal, QC, Canada; Rosalind & Morris Goodman Cancer Research Centre, McGill University, Montreal, QC, Canada.
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54
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Sergeeva O, Zatsepin T. RNA Helicases as Shadow Modulators of Cell Cycle Progression. Int J Mol Sci 2021; 22:2984. [PMID: 33804185 PMCID: PMC8001981 DOI: 10.3390/ijms22062984] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Revised: 03/06/2021] [Accepted: 03/10/2021] [Indexed: 02/07/2023] Open
Abstract
The progress of the cell cycle is directly regulated by modulation of cyclins and cyclin-dependent kinases. However, many proteins that control DNA replication, RNA transcription and the synthesis and degradation of proteins can manage the activity or levels of master cell cycle regulators. Among them, RNA helicases are key participants in RNA metabolism involved in the global or specific tuning of cell cycle regulators at the level of transcription and translation. Several RNA helicases have been recently evaluated as promising therapeutic targets, including eIF4A, DDX3 and DDX5. However, targeting RNA helicases can result in side effects due to the influence on the cell cycle. In this review, we discuss direct and indirect participation of RNA helicases in the regulation of the cell cycle in order to draw attention to downstream events that may occur after suppression or inhibition of RNA helicases.
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Affiliation(s)
- Olga Sergeeva
- Skolkovo Institute of Science and Technology, Bolshoy Boulevard 30b1, 121205 Moscow, Russia;
| | - Timofei Zatsepin
- Skolkovo Institute of Science and Technology, Bolshoy Boulevard 30b1, 121205 Moscow, Russia;
- Department of Chemistry, Lomonosov Moscow State University, 119992 Moscow, Russia
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55
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Targeting the DEAD-Box RNA Helicase eIF4A with Rocaglates-A Pan-Antiviral Strategy for Minimizing the Impact of Future RNA Virus Pandemics. Microorganisms 2021; 9:microorganisms9030540. [PMID: 33807988 PMCID: PMC8001013 DOI: 10.3390/microorganisms9030540] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 03/01/2021] [Accepted: 03/02/2021] [Indexed: 12/17/2022] Open
Abstract
The increase in pandemics caused by RNA viruses of zoonotic origin highlights the urgent need for broad-spectrum antivirals against novel and re-emerging RNA viruses. Broad-spectrum antivirals could be deployed as first-line interventions during an outbreak while virus-specific drugs and vaccines are developed and rolled out. Viruses depend on the host’s protein synthesis machinery for replication. Several natural compounds that target the cellular DEAD-box RNA helicase eIF4A, a key component of the eukaryotic translation initiation complex eIF4F, have emerged as potential broad-spectrum antivirals. Rocaglates, a group of flavaglines of plant origin that clamp mRNAs with highly structured 5′ untranslated regions (5′UTRs) onto the surface of eIF4A through specific stacking interactions, exhibit the largest selectivity and potential therapeutic indices among all known eIF4A inhibitors. Their unique mechanism of action limits the inhibitory effect of rocaglates to the translation of eIF4A-dependent viral mRNAs and a minor fraction of host mRNAs exhibiting stable RNA secondary structures and/or polypurine sequence stretches in their 5′UTRs, resulting in minimal potential toxic side effects. Maintaining a favorable safety profile while inducing efficient inhibition of a broad spectrum of RNA viruses makes rocaglates into primary candidates for further development as pan-antiviral therapeutics.
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56
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Sanghvi VR, Mohan P, Singh K, Cao L, Berishaj M, Wolfe AL, Schatz JH, Lailler N, de Stanchina E, Viale A, Wendel HG. NRF2 Activation Confers Resistance to eIF4A Inhibitors in Cancer Therapy. Cancers (Basel) 2021; 13:cancers13040639. [PMID: 33562682 PMCID: PMC7915661 DOI: 10.3390/cancers13040639] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Revised: 01/29/2021] [Accepted: 01/29/2021] [Indexed: 12/12/2022] Open
Abstract
Simple Summary eIF4A-targeted translational inhibitors, such as silvestrol and its analogues, have emerged as strong anticancer therapies. Here, we tested the efficacy of eIF4A inhibition across a large and diverse panel of cancer cell lines and found B cell lymphomas to be the most sensitive group. Moreover, we performed a genetic screen and identified NRF2 activation as a major mechanism of resistance to silvestrol and related eIF4A inhibitors. Mechanistically, NRF2 activation broadly increases protein synthesis, and this effect is more pronounced on specific mRNAs that require eIF4A for translation. Finally, blocking NRF2 function by preventing its deglycation restores silvestrol sensitivity in cells that harbor NRF2 activation. Overall, our findings indicate that eIF4A inhibitors are a feasible therapeutic option against lymphoma and other cancers and that NRF2 activation status may be an important predictor of their efficacy. Abstract Inhibition of the eIF4A RNA helicase with silvestrol and related compounds is emerging as a powerful anti-cancer strategy. We find that a synthetic silvestrol analogue (CR-1-31 B) has nanomolar activity across many cancer cell lines. It is especially active against aggressive MYC+/BCL2+ B cell lymphomas and this likely reflects the eIF4A-dependent translation of both MYC and BCL2. We performed a genome-wide CRISPR/Cas9 screen and identified mechanisms of resistance to this new class of therapeutics. We identify three negative NRF2 regulators (KEAP1, CUL3, CAND1) whose inactivation is sufficient to cause CR1-31-B resistance. NRF2 is known to alter the oxidation state of translation factors and cause a broad increase in protein production. We find that NRF2 activation particularly increases the translation of some eIF4A-dependent mRNAs and restores MYC and BCL2 production. We know that NRF2 functions depend on removal of sugar adducts by the frutosamine-3-kinase (FN3K). Accordingly, loss of FN3K results in NRF2 hyper-glycation and inactivation and resensitizes cancer cells to eIF4A inhibition. Together, our findings implicate NRF2 in the translation of eIF4A-dependent mRNAs and point to FN3K inhibition as a new strategy to block NRF2 functions in cancer.
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Affiliation(s)
- Viraj R. Sanghvi
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA; (P.M.); (K.S.); (L.C.); (M.B.); (A.L.W.); (J.H.S.); (H.-G.W.)
- Department of Molecular and Cellular Pharmacology, Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, FL 33136, USA
- Correspondence:
| | - Prathibha Mohan
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA; (P.M.); (K.S.); (L.C.); (M.B.); (A.L.W.); (J.H.S.); (H.-G.W.)
| | - Kamini Singh
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA; (P.M.); (K.S.); (L.C.); (M.B.); (A.L.W.); (J.H.S.); (H.-G.W.)
| | - Linlin Cao
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA; (P.M.); (K.S.); (L.C.); (M.B.); (A.L.W.); (J.H.S.); (H.-G.W.)
- Swiss Institute of Experimental Cancer Research, EPFL, 1015 Lausanne, Switzerland
| | - Marjan Berishaj
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA; (P.M.); (K.S.); (L.C.); (M.B.); (A.L.W.); (J.H.S.); (H.-G.W.)
| | - Andrew L. Wolfe
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA; (P.M.); (K.S.); (L.C.); (M.B.); (A.L.W.); (J.H.S.); (H.-G.W.)
- Hellen Diller Comprehensive Cancer Center, University of California, San Francisco, CA 94143, USA
| | - Jonathan H. Schatz
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA; (P.M.); (K.S.); (L.C.); (M.B.); (A.L.W.); (J.H.S.); (H.-G.W.)
- Department of Medicine, Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, FL 33136, USA
| | - Nathalie Lailler
- Integrated Genomics Operation, Marie-Josée and Henry R. Kravis Center for Molecular Oncology, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA; (N.L.); (A.V.)
| | - Elisa de Stanchina
- Department of Antitumor Assessment Core and Molecular Pharmacology, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA;
| | - Agnes Viale
- Integrated Genomics Operation, Marie-Josée and Henry R. Kravis Center for Molecular Oncology, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA; (N.L.); (A.V.)
| | - Hans-Guido Wendel
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA; (P.M.); (K.S.); (L.C.); (M.B.); (A.L.W.); (J.H.S.); (H.-G.W.)
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57
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Smith RCL, Kanellos G, Vlahov N, Alexandrou C, Willis AE, Knight JRP, Sansom OJ. Translation initiation in cancer at a glance. J Cell Sci 2021; 134:jcs248476. [PMID: 33441326 DOI: 10.1242/jcs.248476] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Cell division, differentiation and function are largely dependent on accurate proteome composition and regulated gene expression. To control this, protein synthesis is an intricate process governed by upstream signalling pathways. Eukaryotic translation is a multistep process and can be separated into four distinct phases: initiation, elongation, termination and recycling of ribosomal subunits. Translation initiation, the focus of this article, is highly regulated to control the activity and/or function of eukaryotic initiation factors (eIFs) and permit recruitment of mRNAs to the ribosomes. In this Cell Science at a Glance and accompanying poster, we outline the mechanisms by which tumour cells alter the process of translation initiation and discuss how this benefits tumour formation, proliferation and metastasis.
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Affiliation(s)
- Rachael C L Smith
- CRUK Beatson Institute, Garscube Estate, Switchback Road, Glasgow G61 1BD, UK
- Institute of Cancer Sciences, University of Glasgow, G61 1QH, UK
| | - Georgios Kanellos
- CRUK Beatson Institute, Garscube Estate, Switchback Road, Glasgow G61 1BD, UK
| | - Nikola Vlahov
- CRUK Beatson Institute, Garscube Estate, Switchback Road, Glasgow G61 1BD, UK
| | | | - Anne E Willis
- MRC Toxicology Unit, University of Cambridge, Cambridge CB2 1QW, UK
| | - John R P Knight
- CRUK Beatson Institute, Garscube Estate, Switchback Road, Glasgow G61 1BD, UK
| | - Owen J Sansom
- CRUK Beatson Institute, Garscube Estate, Switchback Road, Glasgow G61 1BD, UK
- Institute of Cancer Sciences, University of Glasgow, G61 1QH, UK
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58
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Minnee E, Faller WJ. Translation initiation and its relevance in colorectal cancer. FEBS J 2021; 288:6635-6651. [PMID: 33382175 PMCID: PMC9291299 DOI: 10.1111/febs.15690] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Revised: 12/22/2020] [Accepted: 12/29/2020] [Indexed: 01/08/2023]
Abstract
Protein synthesis is one of the most essential processes in every kingdom of life, and its dysregulation is a known driving force in cancer development. Multiple signaling pathways converge on the translation initiation machinery, and this plays a crucial role in regulating differential gene expression. In colorectal cancer, dysregulation of initiation results in translational reprogramming, which promotes the selective translation of mRNAs required for many oncogenic processes. The majority of upstream mutations found in colorectal cancer, including alterations in the WNT, MAPK, and PI3K\AKT pathways, have been demonstrated to play a significant role in translational reprogramming. Many translation initiation factors are also known to be dysregulated, resulting in translational reprogramming during tumor initiation and/or maintenance. In this review, we outline the role of translational reprogramming that occurs during colorectal cancer development and progression and highlight some of the most critical factors affecting the etiology of this disease.
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Affiliation(s)
- Emma Minnee
- Division of Oncogenomics, Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - William James Faller
- Division of Oncogenomics, Netherlands Cancer Institute, Amsterdam, The Netherlands
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59
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Thompson PA, Eam B, Young NP, Fish S, Chen J, Barrera M, Howard H, Sung E, Parra A, Staunton J, Chiang GG, Gerson-Gurwitz A, Wegerski CJ, Nevarez A, Clarine J, Sperry S, Xiang A, Nilewski C, Packard GK, Michels T, Tran C, Sprengeler PA, Ernst JT, Reich SH, Webster KR. Targeting Oncogene mRNA Translation in B-Cell Malignancies with eFT226, a Potent and Selective Inhibitor of eIF4A. Mol Cancer Ther 2021; 20:26-36. [PMID: 33037136 DOI: 10.1158/1535-7163.mct-19-0973] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Revised: 02/14/2020] [Accepted: 09/30/2020] [Indexed: 11/16/2022]
Abstract
The PI3K/AKT/mTOR pathway is often activated in lymphoma through alterations in PI3K, PTEN, and B-cell receptor signaling, leading to dysregulation of eIF4A (through its regulators, eIF4B, eIF4G, and PDCD4) and the eIF4F complex. Activation of eIF4F has a direct role in tumorigenesis due to increased synthesis of oncogenes that are dependent on enhanced eIF4A RNA helicase activity for translation. eFT226, which inhibits translation of specific mRNAs by promoting eIF4A1 binding to 5'-untranslated regions (UTR) containing polypurine and/or G-quadruplex recognition motifs, shows potent antiproliferative activity and significant in vivo efficacy against a panel of diffuse large B-cell lymphoma (DLBCL), and Burkitt lymphoma models with ≤1 mg/kg/week intravenous administration. Evaluation of predictive markers of sensitivity or resistance has shown that activation of eIF4A, mediated by mTOR signaling, correlated with eFT226 sensitivity in in vivo xenograft models. Mutation of PTEN is associated with reduced apoptosis in vitro and diminished efficacy in vivo in response to eFT226. In models evaluated with PTEN loss, AKT was stimulated without a corresponding increase in mTOR activation. AKT activation leads to the degradation of PDCD4, which can alter eIF4F complex formation. The association of eFT226 activity with PTEN/PI3K/mTOR pathway regulation of mRNA translation provides a means to identify patient subsets during clinical development.
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Affiliation(s)
| | - Boreth Eam
- eFFECTOR Therapeutics, Inc., San Diego, California
| | | | - Sarah Fish
- eFFECTOR Therapeutics, Inc., San Diego, California
| | - Joan Chen
- eFFECTOR Therapeutics, Inc., San Diego, California
| | | | | | - Eric Sung
- eFFECTOR Therapeutics, Inc., San Diego, California
| | - Ana Parra
- eFFECTOR Therapeutics, Inc., San Diego, California
| | | | | | | | | | | | - Jeff Clarine
- eFFECTOR Therapeutics, Inc., San Diego, California
| | | | - Alan Xiang
- eFFECTOR Therapeutics, Inc., San Diego, California
| | | | | | | | - Chinh Tran
- eFFECTOR Therapeutics, Inc., San Diego, California
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60
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Quantitative Comparisons of Translation Activity by Ribosome Profiling with Internal Standards. Methods Mol Biol 2021; 2252:127-149. [PMID: 33765273 DOI: 10.1007/978-1-0716-1150-0_5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Ribosome profiling is a genome-wide approach to map the positions of ribosomes on messenger RNAs. The abundance of ribosome-protected fragments can be used within condition to compare relative translation activities between different transcripts and between distinct conditions for the same transcript. A unified and routine method is currently lacking, however, to normalize between conditions for differences in global translation levels. Here we describe experimental and computational methods to use an orthogonal species spike-in, or internal standard, to enable absolute comparisons of translation activity between conditions. This simple modification of standard ribosome profiling provides a robust approach for accurately interpreting the effects of diverse genetic, chemical, and environmental perturbations of translation.
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61
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WD Repeat Domain 77 Protein Regulates Translation of E2F1 and E2F3 mRNA. Mol Cell Biol 2020; 40:MCB.00302-20. [PMID: 33020149 DOI: 10.1128/mcb.00302-20] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Accepted: 09/30/2020] [Indexed: 11/20/2022] Open
Abstract
WD repeat domain 77 protein (WDR77) is required for cellular proliferation of lung and prostate epithelial cells during earlier stages of development and is reactivated during prostate and lung tumorigenesis. WDR77 plays an essential role in prostate tumorigenesis and cell growth mediated by growth regulatory factors. Here, we identified E2F1 and E2F3 mRNAs as translational targets of WDR77. We demonstrated that WDR77 regulated the translation of E2F1 and E2F3 mRNAs through the 5' untranslated regions (UTRs) of E2F1 and E2F3 (E2F1/3) mRNAs. WDR77 physically interacted with programmed cell death 4 (PDCD4) that suppresses translation of mRNAs containing structured 5' UTRs by interacting with eukaryotic translation initiation factor 4A (eIF4A) and inhibiting its helicase activity. Further, we demonstrated that the interaction between WDR77 and PDCD4 prevented the binding of PDCD4 to eIF4A and relieved PDCD4's inhibitory effect on eIF4A1. Overall, our work reveals for the first time that WDR77 is directly involved in translational regulation of E2F1/3 mRNAs through their structured 5' UTRs, PDCD4, and eIF4A1 and provides novel insight into the cell growth controlled by WDR77.
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62
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Raman D, Tiwari AK. Role of eIF4A1 in triple-negative breast cancer stem-like cell-mediated drug resistance. Cancer Rep (Hoboken) 2020; 5:e1299. [PMID: 33053607 PMCID: PMC9780423 DOI: 10.1002/cnr2.1299] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 07/29/2020] [Accepted: 08/17/2020] [Indexed: 01/25/2023] Open
Abstract
In cap-dependent translation, the eukaryotic translation initiation factor 4A (eIF4A1) is an mRNA helicase is involved in unwinding of the secondary structure, such as the stem-loops, at the 5'-leader regions of the key oncogenic mRNAs. This facilitates ribosomal scanning and translation of the oncogenic mRNAs. eIF4A1 has a regulatory role in translating many oncoproteins that have vital roles in several steps of metastases. Sridharan et. al. have discovered and provide a novel insight into how eIF4A1 can play a regulatory role in drug resistance by influencing the levels of pluripotent Yamanaka transcription factors and ATP-binding cassette (ABC) transporters in triple-negative breast cancer (TNBC) stem-like cells. These findings may help us understand the molecular underpinnings of chemoresistance, especially in established metastases in TNBC. Importantly, eIF4A1 may form a novel clinical target in metastatic TNBC and the drug eFT226 from Effector Therapeutics targeting eIF4A1 is already in phase1-2 clinical trial.
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Affiliation(s)
- Dayanidhi Raman
- Department of Cancer BiologyUniversity of Toledo Health Science CampusToledoOhio
| | - Amit K. Tiwari
- Department of Pharmacology & Experimental TherapeuticsUniversity of Toledo Health Science CampusToledoOhio
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63
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Lyons SM, Kharel P, Akiyama Y, Ojha S, Dave D, Tsvetkov V, Merrick W, Ivanov P, Anderson P. eIF4G has intrinsic G-quadruplex binding activity that is required for tiRNA function. Nucleic Acids Res 2020; 48:6223-6233. [PMID: 32374873 PMCID: PMC7293036 DOI: 10.1093/nar/gkaa336] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Revised: 04/20/2020] [Accepted: 05/04/2020] [Indexed: 12/13/2022] Open
Abstract
As cells encounter adverse environmental conditions, such as hypoxia, oxidative stress or nutrient deprivation, they trigger stress response pathways to protect themselves until transient stresses have passed. Inhibition of translation is a key component of such cellular stress responses and mounting evidence has revealed the importance of a class of tRNA-derived small RNAs called tiRNAs in this process. The most potent of these small RNAs are those with the capability of assembling into tetrameric G-quadruplex (G4) structures. However, the mechanism by which these small RNAs inhibit translation has yet to be elucidated. Here we show that eIF4G, the major scaffolding protein in the translation initiation complex, directly binds G4s and this activity is required for tiRNA-mediated translation repression. Targeting of eIF4G results in an impairment of 40S ribosome scanning on mRNAs leading to the formation of eIF2α-independent stress granules. Our data reveals the mechanism by which tiRNAs inhibit translation and demonstrates novel activity for eIF4G in the regulation of translation.
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Affiliation(s)
- Shawn M Lyons
- Division of Rheumatology, Inflammation and Immunity, Brigham and Women's Hospital, Boston, MA, USA.,Department of Medicine, Harvard Medical School, Boston, MA, USA.,Department of Biochemistry, Boston University School of Medicine, Boston, MA, USA.,The Genome Science Institute, Boston University School of Medicine, Boston, MA, USA
| | - Prakash Kharel
- Division of Rheumatology, Inflammation and Immunity, Brigham and Women's Hospital, Boston, MA, USA.,Department of Medicine, Harvard Medical School, Boston, MA, USA
| | - Yasutoshi Akiyama
- Division of Rheumatology, Inflammation and Immunity, Brigham and Women's Hospital, Boston, MA, USA.,Department of Medicine, Harvard Medical School, Boston, MA, USA.,Laboratory of Oncology, Pharmacy Practice and Sciences, Tohoku University Graduate School of Pharmaceutical Sciences, Sendai, Japan
| | - Sandeep Ojha
- Department of Biochemistry, Boston University School of Medicine, Boston, MA, USA.,The Genome Science Institute, Boston University School of Medicine, Boston, MA, USA
| | - Dhwani Dave
- Division of Rheumatology, Inflammation and Immunity, Brigham and Women's Hospital, Boston, MA, USA
| | - Vladimir Tsvetkov
- Computational Oncology Group, I.M. Sechenov First Moscow State Medical University , Moscow, Russia.,Federal Research and Clinical Center forPhysical-Chemical Medicine, Federal Medical Biological Agency, Moscow, Russia.,A. V. Topchiev Institute of Petrochemical Synthesis, Russian Academy of Sciences, Moscow, Russia
| | - William Merrick
- Department of Biochemistry, Case Western ReserveUniversity, Cleveland, OH, USA
| | - Pavel Ivanov
- Division of Rheumatology, Inflammation and Immunity, Brigham and Women's Hospital, Boston, MA, USA.,Department of Medicine, Harvard Medical School, Boston, MA, USA
| | - Paul Anderson
- Division of Rheumatology, Inflammation and Immunity, Brigham and Women's Hospital, Boston, MA, USA.,Department of Medicine, Harvard Medical School, Boston, MA, USA
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64
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Slobodin B, Dikstein R. So close, no matter how far: multiple paths connecting transcription to mRNA translation in eukaryotes. EMBO Rep 2020; 21:e50799. [PMID: 32803873 PMCID: PMC7507372 DOI: 10.15252/embr.202050799] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 06/22/2020] [Accepted: 07/23/2020] [Indexed: 12/15/2022] Open
Abstract
Transcription of DNA into mRNA and translation of mRNA into proteins are two major processes underlying gene expression. Due to the distinct molecular mechanisms, timings, and locales of action, these processes are mainly considered to be independent. During the last two decades, however, multiple factors and elements were shown to coordinate transcription and translation, suggesting an intricate level of synchronization. This review discusses the molecular mechanisms that impact both processes in eukaryotic cells of different origins. The emerging global picture suggests evolutionarily conserved regulation and coordination between transcription and mRNA translation, indicating the importance of this phenomenon for the fine-tuning of gene expression and the adjustment to constantly changing conditions.
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Affiliation(s)
- Boris Slobodin
- Department of Biomolecular SciencesThe Weizmann Institute of ScienceRehovotIsrael
| | - Rivka Dikstein
- Department of Biomolecular SciencesThe Weizmann Institute of ScienceRehovotIsrael
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65
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Akirtava C, McManus CJ. Control of translation by eukaryotic mRNA transcript leaders-Insights from high-throughput assays and computational modeling. WILEY INTERDISCIPLINARY REVIEWS-RNA 2020; 12:e1623. [PMID: 32869519 DOI: 10.1002/wrna.1623] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Revised: 07/23/2020] [Accepted: 07/30/2020] [Indexed: 12/21/2022]
Abstract
Eukaryotic gene expression is tightly regulated during translation of mRNA to protein. Mis-regulation of translation can lead to aberrant proteins which accumulate in cancers and cause neurodegenerative diseases. Foundational studies on model genes established fundamental roles for mRNA 5' transcript leader (TL) sequences in controlling ribosome recruitment, scanning, and initiation. TL cis-regulatory elements and their corresponding trans-acting factors control cap-dependent initiation under unstressed conditions. Under stress, cap-dependent initiation is suppressed, and specific mRNA structures and sequences promote translation of stress-responsive transcripts to remodel the proteome. In this review, we summarize current knowledge of TL functions in translation initiation. We focus on insights from high-throughput analyses of ribosome occupancy, mRNA structure, RNA Binding Protein occupancy, and massively parallel reporter assays. These data-driven approaches, coupled with computational analyses and modeling, have paved the way for a comprehensive understanding of TL functions. Finally, we will discuss areas of future research on the roles of mRNA sequences and structures in translation. This article is categorized under: Translation > Translation Mechanisms RNA Evolution and Genomics > Computational Analyses of RNA RNA Structure and Dynamics > Influence of RNA Structure in Biological Systems.
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Affiliation(s)
- Christina Akirtava
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, Pennsylvania, USA
| | - Charles Joel McManus
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, Pennsylvania, USA.,Computational Biology Department, Carnegie Mellon University, Pittsburgh, Pennsylvania, USA
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66
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Webb TE, Davies M, Maher J, Sarker D. The eIF4A inhibitor silvestrol sensitizes T-47D ductal breast carcinoma cells to external-beam radiotherapy. Clin Transl Radiat Oncol 2020; 24:123-126. [PMID: 32875125 PMCID: PMC7451755 DOI: 10.1016/j.ctro.2020.07.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Revised: 07/12/2020] [Accepted: 07/14/2020] [Indexed: 01/05/2023] Open
Abstract
Treatment of T-47D breast cancer cells with silvestrol sensitised them to radiation. 1 nM silvestrol caused a 34% reduction in cells exposed to 2 Gy. Clonogenic assays revealed silvestrol had a dose modifying factor of 1.4. Radiation was delivered to the tissue culture plate using a clinical LINAC machine.
Purpose eIF4A is an RNA helicase that forms part of the machinery of translation initiation. Proteomic analysis demonstrated eIF4A expression to be at least two-fold greater in a radioresistant derivative of T-47D breast cancer cells compared to parental cells. Inhibition of eIF4A has previously been shown to re-sensitize lymphomas to chemotherapeutic agents that cause DNA damage. The objective of this work is to investigate whether inhibition of eIF4A using silvestrol sensitizes breast cancer cells to radiotherapy in tissue culture, using T-47D as a model system. Methods and materials T-47D cells were incubated in medium containing 0 nM to 1 nM silvestrol either for 24 h prior to irradiation at 0 Gy to 10 Gy, delivered by linear accelerator (LINAC) or continually for six days post irradiation. MTT viability and clonogenic assays were used to quantify response. Results Pre-treatment of T-47D cells with 1 nM silvestrol caused a 34% reduction (p = 0.014) in viability on irradiation at 2 Gy compared to treatment with a DMSO control, as assessed by MTT assay. Maintenance of cells in 1 nM silvestrol for six days following irradiation at 2 Gy caused a 58% reduction (p = <0.001) in tumor cell viability. Clonogenic assays performed on cells maintained in 1 nM silvestrol following irradiation showed a dose modifying factor (DMF) of 1.4 (p = <0.001, one-way ANOVA). Conclusions Low concentrations of silvestrol sensitize T-47D breast cancer cells to radiation with minimal effects on unirradiated cells. This highlights the possible usefulness of eIF4A inhibition in potentiating radiation-induced damage at the tumor site without causing systemic toxicity.
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Affiliation(s)
- Thomas E Webb
- Guy's and St Thomas' NHS Foundation Trust, Great Maze Pond, London SE1 9RT, UK
| | - Marc Davies
- Research Oncology, Comprehensive Cancer Centre, 3rd Floor Bermondsey Wing, Guy's Hospital, Great Maze, Pond Road, London SE1 9RT, UK.,King's College London, School of Cancer and Pharmaceutical Sciences, Guy's Cancer Centre, Great Maze, Pond, London SE1 9RT, UK
| | - John Maher
- King's College London, School of Cancer and Pharmaceutical Sciences, Guy's Cancer Centre, Great Maze, Pond, London SE1 9RT, UK.,Department of Clinical Immunology and Allergy, King's College Hospital NHS Foundation Trust, Denmark, Hill, London SE5 9RS, UK.,Department of Immunology, Eastbourne Hospital, Kings Drive, Eastbourne, East Sussex BN21 2UD, UK
| | - Debashis Sarker
- Research Oncology, Comprehensive Cancer Centre, 3rd Floor Bermondsey Wing, Guy's Hospital, Great Maze, Pond Road, London SE1 9RT, UK.,Department of Medical Oncology, Guy's & St Thomas' NHS Trust, London SE1 9RT, UK
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67
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General and Target-Specific DExD/H RNA Helicases in Eukaryotic Translation Initiation. Int J Mol Sci 2020; 21:ijms21124402. [PMID: 32575790 PMCID: PMC7352612 DOI: 10.3390/ijms21124402] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 06/17/2020] [Accepted: 06/18/2020] [Indexed: 12/19/2022] Open
Abstract
DExD (DDX)- and DExH (DHX)-box RNA helicases, named after their Asp-Glu-x-Asp/His motifs, are integral to almost all RNA metabolic processes in eukaryotic cells. They play myriad roles in processes ranging from transcription and mRNA-protein complex remodeling, to RNA decay and translation. This last facet, translation, is an intricate process that involves DDX/DHX helicases and presents a regulatory node that is highly targetable. Studies aimed at better understanding this family of conserved proteins have revealed insights into their structures, catalytic mechanisms, and biological roles. They have also led to the development of chemical modulators that seek to exploit their essential roles in diseases. Herein, we review the most recent insights on several general and target-specific DDX/DHX helicases in eukaryotic translation initiation.
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68
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Kim JK, Cho J, Kim SH, Kang HC, Kim DS, Kim VN, Lee JH. Brain somatic mutations in MTOR reveal translational dysregulations underlying intractable focal epilepsy. J Clin Invest 2020; 129:4207-4223. [PMID: 31483294 DOI: 10.1172/jci127032] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2018] [Accepted: 07/03/2019] [Indexed: 12/15/2022] Open
Abstract
Brain somatic mutations confer genomic diversity in the human brain and cause neurodevelopmental disorders. Recently, brain somatic activating mutations in MTOR have been identified as a major etiology of intractable epilepsy in patients with cortical malformations. However, the molecular genetic mechanism of how brain somatic mutations in MTOR cause intractable epilepsy has remained elusive. In this study, translational profiling of intractable epilepsy mouse models with brain somatic mutations and genome-edited cells revealed a novel translational dysregulation mechanism and mTOR activation-sensitive targets mediated by human MTOR mutations that lead to intractable epilepsy with cortical malformation. These mTOR targets were found to be regulated by novel mTOR-responsive 5'-UTR motifs, distinct from known mTOR inhibition-sensitive targets regulated by 5' terminal oligopyrimidine motifs. Novel mTOR target genes were validated in patient brain tissues, and the mTOR downstream effector eIF4E was identified as a new therapeutic target in intractable epilepsy via pharmacological or genetic inhibition. We show that metformin, an FDA-approved eIF4E inhibitor, suppresses intractable epilepsy. Altogether, the present study describes translational dysregulation resulting from brain somatic mutations in MTOR, as well as the pathogenesis and potential therapeutic targets of intractable epilepsy.
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Affiliation(s)
- Jang Keun Kim
- Biomedical Science and Engineering Interdisciplinary Program, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea
| | - Jun Cho
- Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology, Gwangju, Republic of Korea.,Center for RNA Research, Institute for Basic Science, Seoul, Republic of Korea
| | - Se Hoon Kim
- Department of Pathology, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Hoon-Chul Kang
- Division of Pediatric Neurology, Department of Pediatrics, Pediatric Epilepsy Clinics, Severance Children's Hospital, Epilepsy Research Institute, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Dong-Seok Kim
- Epilepsy Research Institute, Yonsei University College of Medicine, Seoul, Republic of Korea.,Department of Neurosurgery, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - V Narry Kim
- Center for RNA Research, Institute for Basic Science, Seoul, Republic of Korea.,Department of Biological Sciences, Seoul National University, Seoul, Republic of Korea
| | - Jeong Ho Lee
- Biomedical Science and Engineering Interdisciplinary Program, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea.,Graduate School of Medical Science and Engineering, KAIST, Daejeon, Republic of Korea
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69
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Translational profiling of macrophages infected with Leishmania donovani identifies mTOR- and eIF4A-sensitive immune-related transcripts. PLoS Pathog 2020; 16:e1008291. [PMID: 32479529 PMCID: PMC7310862 DOI: 10.1371/journal.ppat.1008291] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 06/23/2020] [Accepted: 05/13/2020] [Indexed: 12/28/2022] Open
Abstract
The protozoan parasite Leishmania donovani (L. donovani) causes visceral leishmaniasis, a chronic infection which is fatal when untreated. Herein, we investigated whether in addition to altering transcription, L. donovani modulates host mRNA translation to establish a successful infection. Polysome-profiling revealed that one third of protein-coding mRNAs expressed in primary mouse macrophages are differentially translated upon infection with L. donovani promastigotes or amastigotes. Gene ontology analysis identified key biological processes enriched for translationally regulated mRNAs and were predicted to be either activated (e.g. chromatin remodeling and RNA metabolism) or inhibited (e.g. intracellular trafficking and antigen presentation) upon infection. Mechanistic in silico and biochemical analyses showed selective activation mTOR- and eIF4A-dependent mRNA translation, including transcripts encoding central regulators of mRNA turnover and inflammation (i.e. PABPC1, EIF2AK2, and TGF-β). L. donovani survival within macrophages was favored under mTOR inhibition but was dampened by pharmacological blockade of eIF4A. Overall, this study uncovers a vast yet selective reprogramming of the host cell translational landscape early during L. donovani infection, and suggests that some of these changes are involved in host defense mechanisms while others are part of parasite-driven survival strategies. Further in vitro and in vivo investigation will shed light on the contribution of mTOR- and eIF4A-dependent translational programs to the outcome of visceral leishmaniasis.
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70
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Philippe L, van den Elzen AMG, Watson MJ, Thoreen CC. Global analysis of LARP1 translation targets reveals tunable and dynamic features of 5' TOP motifs. Proc Natl Acad Sci U S A 2020; 117:5319-5328. [PMID: 32094190 PMCID: PMC7071917 DOI: 10.1073/pnas.1912864117] [Citation(s) in RCA: 87] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Terminal oligopyrimidine (TOP) motifs are sequences at the 5' ends of mRNAs that link their translation to the mTOR Complex 1 (mTORC1) nutrient-sensing signaling pathway. They are commonly regarded as discrete elements that reside on ∼100 mRNAs that mostly encode translation factors. However, the full spectrum of TOP sequences and their prevalence throughout the transcriptome remain unclear, primarily because of uncertainty over the mechanism that detects them. Here, we globally analyzed translation targets of La-related protein 1 (LARP1), an RNA-binding protein and mTORC1 effector that has been shown to repress TOP mRNA translation in a few specific cases. We establish that LARP1 is the primary translation regulator of mRNAs with classical TOP motifs genome-wide, and also that these motifs are extreme instances of a broader continuum of regulatory sequences. We identify the features of TOP sequences that determine their potency and quantify these as a metric that accurately predicts mTORC1/LARP1 regulation called a TOPscore. Analysis of TOPscores across the transcriptomes of 16 mammalian tissues defines a constitutive "core" set of TOP mRNAs, but also identifies tissue-specific TOP mRNAs produced via alternative transcription initiation sites. These results establish the central role of LARP1 in TOP mRNA regulation on a transcriptome scale and show how it connects mTORC1 to a tunable and dynamic program of gene expression that is tailored to specific biological contexts.
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Affiliation(s)
- Lucas Philippe
- Department of Cellular and Molecular Physiology, Yale School of Medicine, New Haven, CT 06510
| | | | - Maegan J Watson
- Department of Cellular and Molecular Physiology, Yale School of Medicine, New Haven, CT 06510
| | - Carson C Thoreen
- Department of Cellular and Molecular Physiology, Yale School of Medicine, New Haven, CT 06510
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71
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Taylor J, Yeomans AM, Packham G. Targeted inhibition of mRNA translation initiation factors as a novel therapeutic strategy for mature B-cell neoplasms. EXPLORATION OF TARGETED ANTI-TUMOR THERAPY 2020; 1:3-25. [PMID: 32924027 PMCID: PMC7116065 DOI: 10.37349/etat.2020.00002] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Accepted: 01/31/2020] [Indexed: 12/17/2022] Open
Abstract
Cancer development is frequently associated with dysregulation of mRNA translation to enhance both increased global protein synthesis and translation of specific mRNAs encoding oncoproteins. Thus, targeted inhibition of mRNA translation is viewed as a promising new approach for cancer therapy. In this article we review current progress in investigating dysregulation of mRNA translation initiation in mature B-cell neoplasms, focusing on chronic lymphocytic leukemia, follicular lymphoma and diffuse large B-cell lymphoma. We discuss mechanisms and regulation of mRNA translation, potential pathways by which genetic alterations and the tumor microenvironment alters mRNA translation in malignant B cells, preclinical evaluation of drugs targeted against specific eukaryotic initiation factors and current progress towards clinical development. Overall, inhibition of mRNA translation initiation factors is an exciting and promising area for development of novel targeted anti-tumor drugs.
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Affiliation(s)
- Joe Taylor
- Cancer Research UK Centre, Cancer Sciences, Faculty of Medicine, University of Southampton, SO16 6YD Southampton, United Kingdom
| | - Alison M Yeomans
- Cancer Research UK Centre, Cancer Sciences, Faculty of Medicine, University of Southampton, SO16 6YD Southampton, United Kingdom
| | - Graham Packham
- Cancer Research UK Centre, Cancer Sciences, Faculty of Medicine, University of Southampton, SO16 6YD Southampton, United Kingdom
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72
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Müller C, Obermann W, Schulte FW, Lange-Grünweller K, Oestereich L, Elgner F, Glitscher M, Hildt E, Singh K, Wendel HG, Hartmann RK, Ziebuhr J, Grünweller A. Comparison of broad-spectrum antiviral activities of the synthetic rocaglate CR-31-B (-) and the eIF4A-inhibitor Silvestrol. Antiviral Res 2020; 175:104706. [PMID: 31931103 PMCID: PMC7114339 DOI: 10.1016/j.antiviral.2020.104706] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Revised: 01/04/2020] [Accepted: 01/08/2020] [Indexed: 12/22/2022]
Abstract
Rocaglates, a class of natural compounds isolated from plants of the genus Aglaia, are potent inhibitors of translation initiation. They are proposed to form stacking interactions with polypurine sequences in the 5′-untranslated region (UTR) of selected mRNAs, thereby clamping the RNA substrate onto eIF4A and causing inhibition of the translation initiation complex. Since virus replication relies on the host translation machinery, it is not surprising that the rocaglate Silvestrol has broad-spectrum antiviral activity. Unfortunately, synthesis of Silvestrol is sophisticated and time-consuming, thus hampering the prospects for further antiviral drug development. Here, we present the less complex structured synthetic rocaglate CR-31-B (−) as a novel compound with potent broad-spectrum antiviral activity in primary cells and in an ex vivo bronchial epithelial cell system. CR-31-B (−) inhibited the replication of corona-, Zika-, Lassa-, Crimean Congo hemorrhagic fever viruses and, to a lesser extent, hepatitis E virus (HEV) at non-cytotoxic low nanomolar concentrations. Since HEV has a polypurine-free 5′-UTR that folds into a stable hairpin structure, we hypothesized that RNA clamping by Silvestrol and its derivatives may also occur in a polypurine-independent but structure-dependent manner. Interestingly, the HEV 5′-UTR conferred sensitivity towards Silvestrol but not to CR-31-B (−). However, if an exposed polypurine stretch was introduced into the HEV 5′-UTR, CR-31-B (−) became an active inhibitor comparable to Silvestrol. Moreover, thermodynamic destabilization of the HEV 5′-UTR led to reduced translational inhibition by Silvestrol, suggesting differences between rocaglates in their mode of action, most probably by engaging Silvestrol's additional dioxane moiety. The synthetic rocaglate CR-31-B (−) has broad-spectrum antiviral activity comparable to that of Silvestrol. Both compounds show remarkably low cytotoxicity in primary cells. Silvestrol and CR-31-B (−) are highly efficient against HCoV-229E in a primary human bronchial epithelial cell system. Both compounds reduce LASV and CCHFV titers by about 3–4 logs in primary murine hepatocytes. Only Silvestrol with its characteristic dioxane moiety can clamp polypurine-free structured RNAs onto the eIF4A helicase.
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Affiliation(s)
- Christin Müller
- Institut für Medizinische Virologie, Justus-Liebig-Universität Gießen, Schubertstraße 81, 35392, Gießen, Germany; Deutsches Zentrum für Infektionsforschung (DZIF) at the Partner Site Gießen-Marburg-Langen, Germany
| | - Wiebke Obermann
- Institut für Pharmazeutische Chemie, Philipps-Universität Marburg, Marbacher Weg 6, 35032, Marburg, Germany
| | - Falk W Schulte
- Institut für Pharmazeutische Chemie, Philipps-Universität Marburg, Marbacher Weg 6, 35032, Marburg, Germany
| | - Kerstin Lange-Grünweller
- Institut für Pharmazeutische Chemie, Philipps-Universität Marburg, Marbacher Weg 6, 35032, Marburg, Germany
| | - Lisa Oestereich
- Bernhard-Nocht-Institut für Tropenmedizin, Abteilung Virologie, Hamburg, Germany; Deutsches Zentrum für Infektionsforschung (DZIF) at the Partner Site Hamburg, Germany
| | - Fabian Elgner
- Paul-Ehrlich-Institut, Bundesinstitut für Impfstoffe und Biomedizinische Arzneimittel, Abteilung Virologie, Paul-Ehrlich-Straße 51-59, 63225, Langen, Germany
| | - Mirco Glitscher
- Paul-Ehrlich-Institut, Bundesinstitut für Impfstoffe und Biomedizinische Arzneimittel, Abteilung Virologie, Paul-Ehrlich-Straße 51-59, 63225, Langen, Germany
| | - Eberhard Hildt
- Paul-Ehrlich-Institut, Bundesinstitut für Impfstoffe und Biomedizinische Arzneimittel, Abteilung Virologie, Paul-Ehrlich-Straße 51-59, 63225, Langen, Germany
| | - Kamini Singh
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, New York, NY, 10023, USA
| | - Hans-Guido Wendel
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, New York, NY, 10023, USA
| | - Roland K Hartmann
- Institut für Pharmazeutische Chemie, Philipps-Universität Marburg, Marbacher Weg 6, 35032, Marburg, Germany
| | - John Ziebuhr
- Institut für Medizinische Virologie, Justus-Liebig-Universität Gießen, Schubertstraße 81, 35392, Gießen, Germany; Deutsches Zentrum für Infektionsforschung (DZIF) at the Partner Site Gießen-Marburg-Langen, Germany
| | - Arnold Grünweller
- Institut für Pharmazeutische Chemie, Philipps-Universität Marburg, Marbacher Weg 6, 35032, Marburg, Germany.
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Waldron JA, Tack DC, Ritchey LE, Gillen SL, Wilczynska A, Turro E, Bevilacqua PC, Assmann SM, Bushell M, Le Quesne J. mRNA structural elements immediately upstream of the start codon dictate dependence upon eIF4A helicase activity. Genome Biol 2019; 20:300. [PMID: 31888698 PMCID: PMC6936103 DOI: 10.1186/s13059-019-1901-2] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Accepted: 11/26/2019] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND The RNA helicase eIF4A1 is a key component of the translation initiation machinery and is required for the translation of many pro-oncogenic mRNAs. There is increasing interest in targeting eIF4A1 therapeutically in cancer, thus understanding how this protein leads to the selective re-programming of the translational landscape is critical. While it is known that eIF4A1-dependent mRNAs frequently have long GC-rich 5'UTRs, the details of how 5'UTR structure is resculptured by eIF4A1 to enhance the translation of specific mRNAs are unknown. RESULTS Using Structure-seq2 and polysome profiling, we assess global mRNA structure and translational efficiency in MCF7 cells, with and without eIF4A inhibition with hippuristanol. We find that eIF4A inhibition does not lead to global increases in 5'UTR structure, but rather it leads to 5'UTR remodeling, with localized gains and losses of structure. The degree of these localized structural changes is associated with 5'UTR length, meaning that eIF4A-dependent mRNAs have greater localized gains of structure due to their increased 5'UTR length. However, it is not solely increased localized structure that causes eIF4A-dependency but the position of the structured regions, as these structured elements are located predominantly at the 3' end of the 5'UTR. CONCLUSIONS By measuring changes in RNA structure following eIF4A inhibition, we show that eIF4A remodels local 5'UTR structures. The location of these structural elements ultimately determines the dependency on eIF4A, with increased structure just upstream of the CDS being the major limiting factor in translation, which is overcome by eIF4A activity.
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Affiliation(s)
- Joseph A Waldron
- Cancer Research UK Beatson Institute, Garscube Estate, Switchback Road, Glasgow, G61 1BD, UK.
| | - David C Tack
- Department of Biology, Pennsylvania State University, University Park, PA, 16802, USA
- Department of Chemistry, Pennsylvania State University, University Park, PA, 16802, USA
- Present Address: Spectrum Health Office of Research, 100 Michigan Street NE, Mail Code 038, Grand Rapids, MI, 49503, USA
| | - Laura E Ritchey
- Department of Chemistry, Pennsylvania State University, University Park, PA, 16802, USA
- Center for RNA Molecular Biology, Pennsylvania State University, University Park, PA, 16802, USA
- Present Address: Department of Chemistry, University of Pittsburgh at Johnstown, Johnstown, PA, 15904, USA
| | - Sarah L Gillen
- Cancer Research UK Beatson Institute, Garscube Estate, Switchback Road, Glasgow, G61 1BD, UK
| | - Ania Wilczynska
- Cancer Research UK Beatson Institute, Garscube Estate, Switchback Road, Glasgow, G61 1BD, UK
| | - Ernest Turro
- Department of Haematology, University of Cambridge, Cambridge, UK
- Medical Research Council Biostatistics Unit, Cambridge Institute of Public Health, Cambridge, UK
- National Health Service Blood and Transplant, Cambridge, UK
- National Institute for Health Research BioResource, Cambridge University Hospitals, Cambridge, UK
| | - Philip C Bevilacqua
- Department of Chemistry, Pennsylvania State University, University Park, PA, 16802, USA
- Center for RNA Molecular Biology, Pennsylvania State University, University Park, PA, 16802, USA
- Department of Biochemistry & Molecular Biology, Pennsylvania State University, University Park, PA, 16802, USA
| | - Sarah M Assmann
- Department of Biology, Pennsylvania State University, University Park, PA, 16802, USA
- Center for RNA Molecular Biology, Pennsylvania State University, University Park, PA, 16802, USA
| | - Martin Bushell
- Cancer Research UK Beatson Institute, Garscube Estate, Switchback Road, Glasgow, G61 1BD, UK.
- Institute of Cancer Sciences, University of Glasgow, Garscube Estate, Switchback Road, Glasgow, G61 1QH, UK.
| | - John Le Quesne
- Medical Research Council Toxicology Unit, University of Cambridge, Hodgkin Building, Lancaster Road, Leicester, LE1 7HB, UK.
- Leicester Cancer Research Centre, University of Leicester, Leicester, UK.
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74
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Wilczynska A, Gillen SL, Schmidt T, Meijer HA, Jukes-Jones R, Langlais C, Kopra K, Lu WT, Godfrey JD, Hawley BR, Hodge K, Zanivan S, Cain K, Le Quesne J, Bushell M. eIF4A2 drives repression of translation at initiation by Ccr4-Not through purine-rich motifs in the 5'UTR. Genome Biol 2019; 20:262. [PMID: 31791371 PMCID: PMC6886185 DOI: 10.1186/s13059-019-1857-2] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Accepted: 10/10/2019] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND Regulation of the mRNA life cycle is central to gene expression control and determination of cell fate. miRNAs represent a critical mRNA regulatory mechanism, but despite decades of research, their mode of action is still not fully understood. RESULTS Here, we show that eIF4A2 is a major effector of the repressive miRNA pathway functioning via the Ccr4-Not complex. We demonstrate that while DDX6 interacts with Ccr4-Not, its effects in the mechanism are not as pronounced. Through its interaction with the Ccr4-Not complex, eIF4A2 represses mRNAs at translation initiation. We show evidence that native eIF4A2 has similar RNA selectivity to chemically inhibited eIF4A1. eIF4A2 exerts its repressive effect by binding purine-rich motifs which are enriched in the 5'UTR of target mRNAs directly upstream of the AUG start codon. CONCLUSIONS Our data support a model whereby purine motifs towards the 3' end of the 5'UTR are associated with increased ribosome occupancy and possible uORF activation upon eIF4A2 binding.
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Affiliation(s)
- Ania Wilczynska
- Cancer Research UK Beatson Institute, Garscube Estate, Switchback Road, Glasgow, G61 1BD, UK.
- Institute of Cancer Sciences, University of Glasgow, Glasgow, UK.
| | - Sarah L Gillen
- Cancer Research UK Beatson Institute, Garscube Estate, Switchback Road, Glasgow, G61 1BD, UK
- MRC Toxicology Unit, Lancaster Road, Leicester, LE1 9HN, UK
| | - Tobias Schmidt
- Cancer Research UK Beatson Institute, Garscube Estate, Switchback Road, Glasgow, G61 1BD, UK
| | - Hedda A Meijer
- MRC Toxicology Unit, Lancaster Road, Leicester, LE1 9HN, UK
- Present Address: Division of Cell and Developmental Biology, School of Life Sciences, University of Dundee, Dundee, DD1 5EH, UK
| | | | | | - Kari Kopra
- MRC Toxicology Unit, Lancaster Road, Leicester, LE1 9HN, UK
- Present Address: Department of Chemistry, University of Turku, Vatselankatu 2, FI-20500, Turku, Finland
| | - Wei-Ting Lu
- MRC Toxicology Unit, Lancaster Road, Leicester, LE1 9HN, UK
| | - Jack D Godfrey
- MRC Toxicology Unit, Lancaster Road, Leicester, LE1 9HN, UK
| | | | - Kelly Hodge
- Cancer Research UK Beatson Institute, Garscube Estate, Switchback Road, Glasgow, G61 1BD, UK
| | - Sara Zanivan
- Cancer Research UK Beatson Institute, Garscube Estate, Switchback Road, Glasgow, G61 1BD, UK
- Institute of Cancer Sciences, University of Glasgow, Glasgow, UK
| | - Kelvin Cain
- MRC Toxicology Unit, Lancaster Road, Leicester, LE1 9HN, UK
| | - John Le Quesne
- MRC Toxicology Unit, Lancaster Road, Leicester, LE1 9HN, UK
| | - Martin Bushell
- Cancer Research UK Beatson Institute, Garscube Estate, Switchback Road, Glasgow, G61 1BD, UK.
- Institute of Cancer Sciences, University of Glasgow, Glasgow, UK.
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75
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Díaz-López I, Toribio R, Berlanga JJ, Ventoso I. An mRNA-binding channel in the ES6S region of the translation 48S-PIC promotes RNA unwinding and scanning. eLife 2019; 8:48246. [PMID: 31789591 PMCID: PMC6887119 DOI: 10.7554/elife.48246] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Accepted: 11/16/2019] [Indexed: 11/30/2022] Open
Abstract
Loading of mRNA onto the ribosomal 43S pre-initiation complex (PIC) and its subsequent scanning require the removal of the secondary structure of the by RNA helicases such as eIF4A. However, the topology and mechanics of the scanning complex bound to mRNA (48S-PIC) and the influence of its solvent-side composition on the scanning process are poorly known. Here, we found that the ES6S region of the 48S-PIC constitutes an extended binding channel for eIF4A-mediated unwinding of mRNA and scanning. Blocking ES6S inhibited the cap-dependent translation of mRNAs that have structured 5′ UTRs (including G-quadruplexes), many of which are involved in signal transduction and growth, but it did not affect IRES-driven translation. Genome-wide analysis of mRNA translation revealed a great diversity in ES6S-mediated scanning dependency. Our data suggest that mRNA threading into the ES6S region makes scanning by 48S PIC slower but more processive. Hence, we propose a topological and functional model of the scanning 48S-PIC.
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Affiliation(s)
- Irene Díaz-López
- Centro de Biología Molecular "Severo Ochoa" (CSIC-UAM), Departamento de Biología Molecular, Universidad Autónoma de Madrid (UAM), Madrid, Spain
| | - René Toribio
- Centro de Biotecnología y Genómica de Plantas, Madrid, Spain
| | - Juan José Berlanga
- Centro de Biología Molecular "Severo Ochoa" (CSIC-UAM), Departamento de Biología Molecular, Universidad Autónoma de Madrid (UAM), Madrid, Spain
| | - Iván Ventoso
- Centro de Biología Molecular "Severo Ochoa" (CSIC-UAM), Departamento de Biología Molecular, Universidad Autónoma de Madrid (UAM), Madrid, Spain
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76
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Shen L, Pelletier J. Selective targeting of the DEAD-box RNA helicase eukaryotic initiation factor (eIF) 4A by natural products. Nat Prod Rep 2019; 37:609-616. [PMID: 31782447 DOI: 10.1039/c9np00052f] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Covering: up to 2019Pharmacological targeting of eukaryotic mRNA translation initiation is a promising approach for cancer therapy, since several signaling pathways that are commonly deregulated during tumor progression converge on this process. The DEAD-box helicase, eukaryotic initiation factor (eIF) 4A, is essential for translation initiation and facilitates the loading of the 43S pre-initiation complex onto mRNAs. Hippuristanol, rocaglates, and pateamine A are natural products that each target eIF4A by interfering with the helicase's RNA-binding activity in distinct manners. They exert a selective change in gene expression that results in potent anti-tumorigenic activity in pre-clinical studies. This review will provide an update on the molecular mechanisms of action of these natural products.
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Affiliation(s)
- Leo Shen
- Department of Biochemistry, McGill University, Montreal, Quebec H3G 1Y6, Canada.
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77
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Chan K, Robert F, Oertlin C, Kapeller-Libermann D, Avizonis D, Gutierrez J, Handly-Santana A, Doubrovin M, Park J, Schoepfer C, Da Silva B, Yao M, Gorton F, Shi J, Thomas CJ, Brown LE, Porco JA, Pollak M, Larsson O, Pelletier J, Chio IIC. eIF4A supports an oncogenic translation program in pancreatic ductal adenocarcinoma. Nat Commun 2019; 10:5151. [PMID: 31723131 PMCID: PMC6853918 DOI: 10.1038/s41467-019-13086-5] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2018] [Accepted: 10/18/2019] [Indexed: 12/16/2022] Open
Abstract
Pancreatic ductal adenocarcinoma (PDA) is a lethal malignancy with limited treatment options. Although metabolic reprogramming is a hallmark of many cancers, including PDA, previous attempts to target metabolic changes therapeutically have been stymied by drug toxicity and tumour cell plasticity. Here, we show that PDA cells engage an eIF4F-dependent translation program that supports redox and central carbon metabolism. Inhibition of the eIF4F subunit, eIF4A, using the synthetic rocaglate CR-1-31-B (CR-31) reduced the viability of PDA organoids relative to their normal counterparts. In vivo, CR-31 suppresses tumour growth and extends survival of genetically-engineered murine models of PDA. Surprisingly, inhibition of eIF4A also induces glutamine reductive carboxylation. As a consequence, combined targeting of eIF4A and glutaminase activity more effectively inhibits PDA cell growth both in vitro and in vivo. Overall, our work demonstrates the importance of eIF4A in translational control of pancreatic tumour metabolism and as a therapeutic target against PDA.
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Affiliation(s)
- Karina Chan
- Institute for Cancer Genetics, Department of Genetics and Development, Columbia University Medical Center, New York, NY, 10032, USA
| | - Francis Robert
- Department of Biochemistry, Oncology and Goodman Cancer Centre, McGill University, Montreal, H3G 1Y6, QC, Canada
| | - Christian Oertlin
- Department of Oncology-Pathology, Karolinska Institute, Stockholm, Sweden
| | - Dana Kapeller-Libermann
- Institute for Cancer Genetics, Department of Genetics and Development, Columbia University Medical Center, New York, NY, 10032, USA
| | - Daina Avizonis
- Department of Biochemistry, Oncology and Goodman Cancer Centre, McGill University, Montreal, H3G 1Y6, QC, Canada
| | - Johana Gutierrez
- Institute for Cancer Genetics, Department of Genetics and Development, Columbia University Medical Center, New York, NY, 10032, USA
| | - Abram Handly-Santana
- Institute for Cancer Genetics, Department of Genetics and Development, Columbia University Medical Center, New York, NY, 10032, USA
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, 11724, USA
| | - Mikhail Doubrovin
- Department of Radiology, Columbia University Medical Center, New York, NY, 10032, USA
| | - Julia Park
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, 11724, USA
- Department of Chemistry, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | | | - Brandon Da Silva
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, 11724, USA
- SUNY Downstate College of Medicine, SUNY Downstate Medical Center, Brooklyn, NY, 11203, USA
| | - Melissa Yao
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, 11724, USA
| | - Faith Gorton
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, 11724, USA
| | - Junwei Shi
- Department of Cancer Biology, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | | | - Lauren E Brown
- Department of Chemistry and Center for Molecular Discovery (BU-CMD), Boston University, Boston, MA, 02215, USA
| | - John A Porco
- Department of Chemistry and Center for Molecular Discovery (BU-CMD), Boston University, Boston, MA, 02215, USA
| | - Michael Pollak
- Department of Medicine and Oncology, McGill University, Montreal, QC, Canada
| | - Ola Larsson
- Department of Oncology-Pathology, Karolinska Institute, Stockholm, Sweden.
| | - Jerry Pelletier
- Department of Biochemistry, Oncology and Goodman Cancer Centre, McGill University, Montreal, H3G 1Y6, QC, Canada.
| | - Iok In Christine Chio
- Institute for Cancer Genetics, Department of Genetics and Development, Columbia University Medical Center, New York, NY, 10032, USA.
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Verbruggen S, Menschaert G. mQC: A post-mapping data exploration tool for ribosome profiling. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2019; 181:104806. [PMID: 30401579 DOI: 10.1016/j.cmpb.2018.10.018] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Revised: 10/05/2018] [Accepted: 10/26/2018] [Indexed: 06/08/2023]
Abstract
BACKGROUND AND OBJECTIVE Ribosome profiling is a recent next generation sequencing technique enabling the genome-wide study of gene expression in biomedical research at the translation level. Too often, researchers precipitously start trying to test their hypotheses after alignment of their data, without checking the quality and the general features of their mapped data. Despite the fact that these checks are essential to prevent errors and ensure valid conclusions afterwards, easy-to-use tools for visualizing the quality and overall outlook of mapped ribosome profiling data are lacking. METHODS We present mQC, a modular tool implemented as a Bioconda package and also available in the Galaxy tool shed. Herewith both bio-informaticians as well as non-experts can easily perform the indispensable visualization of both the quality and the general features of their mapped P-site corrected ribosome profiling reads. The user manual, the raw code and more information can be found on its GitHub repository (https://github.com/Biobix/mQC). RESULTS mQC was tested on multiple datasets to assess its general applicability and was compared to other tools that partly perform similar tasks. CONCLUSIONS Our results demonstrate that mQC can accomplish an unfilled but essential position in the ribosome profiling data analysis procedure by performing a thorough RIBO-Seq-specific exploration of aligned and P-site corrected ribosome profiling data.
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Affiliation(s)
- Steven Verbruggen
- BioBix, Lab of Bioinformatics and Computational Genomics, Department of Mathematical Modelling, Statistics and Bioinformatics, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, Ghent 9000, Belgium.
| | - Gerben Menschaert
- BioBix, Lab of Bioinformatics and Computational Genomics, Department of Mathematical Modelling, Statistics and Bioinformatics, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, Ghent 9000, Belgium.
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79
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Schmidt S, Gay D, Uthe FW, Denk S, Paauwe M, Matthes N, Diefenbacher ME, Bryson S, Warrander FC, Erhard F, Ade CP, Baluapuri A, Walz S, Jackstadt R, Ford C, Vlachogiannis G, Valeri N, Otto C, Schülein-Völk C, Maurus K, Schmitz W, Knight JRP, Wolf E, Strathdee D, Schulze A, Germer CT, Rosenwald A, Sansom OJ, Eilers M, Wiegering A. A MYC-GCN2-eIF2α negative feedback loop limits protein synthesis to prevent MYC-dependent apoptosis in colorectal cancer. Nat Cell Biol 2019; 21:1413-1424. [PMID: 31685988 PMCID: PMC6927814 DOI: 10.1038/s41556-019-0408-0] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Accepted: 09/20/2019] [Indexed: 12/12/2022]
Abstract
Tumours depend on altered rates of protein synthesis for growth and survival, which suggests that mechanisms controlling mRNA translation may be exploitable for therapy. Here, we show that loss of APC, which occurs almost universally in colorectal tumours, strongly enhances the dependence on the translation initiation factor eIF2B5. Depletion of eIF2B5 induces an integrated stress response and enhances translation of MYC via an internal ribosomal entry site. This perturbs cellular amino acid and nucleotide pools, strains energy resources and causes MYC-dependent apoptosis. eIF2B5 limits MYC expression and prevents apoptosis in APC-deficient murine and patient-derived organoids and in APC-deficient murine intestinal epithelia in vivo. Conversely, the high MYC levels present in APC-deficient cells induce phosphorylation of eIF2α via the kinases GCN2 and PKR. Pharmacological inhibition of GCN2 phenocopies eIF2B5 depletion and has therapeutic efficacy in tumour organoids, which demonstrates that a negative MYC-eIF2α feedback loop constitutes a targetable vulnerability of colorectal tumours.
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Affiliation(s)
- Stefanie Schmidt
- Theodor Boveri Institute, Biocenter, University of Würzburg, Am Hubland, Würzburg, Germany
- Department of General, Visceral, Vascular and Pediatric Surgery, University Hospital Würzburg, Würzburg, Germany
| | | | - Friedrich Wilhelm Uthe
- Theodor Boveri Institute, Biocenter, University of Würzburg, Am Hubland, Würzburg, Germany
- Department of General, Visceral, Vascular and Pediatric Surgery, University Hospital Würzburg, Würzburg, Germany
| | - Sarah Denk
- Theodor Boveri Institute, Biocenter, University of Würzburg, Am Hubland, Würzburg, Germany
- Department of General, Visceral, Vascular and Pediatric Surgery, University Hospital Würzburg, Würzburg, Germany
| | | | - Niels Matthes
- Theodor Boveri Institute, Biocenter, University of Würzburg, Am Hubland, Würzburg, Germany
- Department of General, Visceral, Vascular and Pediatric Surgery, University Hospital Würzburg, Würzburg, Germany
| | | | | | | | - Florian Erhard
- Institute for Virology and Immunobiology, University of Würzburg, Würzburg, Germany
| | - Carsten Patrick Ade
- Theodor Boveri Institute, Biocenter, University of Würzburg, Am Hubland, Würzburg, Germany
| | - Apoorva Baluapuri
- Theodor Boveri Institute, Biocenter, University of Würzburg, Am Hubland, Würzburg, Germany
| | - Susanne Walz
- Comprehensive Cancer Center Mainfranken, Core Unit Bioinformatics, Biocenter, University of Würzburg, Am Hubland, Würzburg, Germany
| | | | | | | | - Nicola Valeri
- Division of Molecular Pathology, The Institute of Cancer Research, London, UK
- Department of Medicine, The Royal Marsden NHS Trust, London, UK
| | - Christoph Otto
- Department of General, Visceral, Vascular and Pediatric Surgery, University Hospital Würzburg, Würzburg, Germany
| | | | - Katja Maurus
- Comprehensive Cancer Center Mainfranken, University of Würzburg, Würzburg, Germany
| | - Werner Schmitz
- Theodor Boveri Institute, Biocenter, University of Würzburg, Am Hubland, Würzburg, Germany
| | | | - Elmar Wolf
- Theodor Boveri Institute, Biocenter, University of Würzburg, Am Hubland, Würzburg, Germany
| | | | - Almut Schulze
- Theodor Boveri Institute, Biocenter, University of Würzburg, Am Hubland, Würzburg, Germany
- Comprehensive Cancer Center Mainfranken, University of Würzburg, Würzburg, Germany
| | - Christoph-Thomas Germer
- Department of General, Visceral, Vascular and Pediatric Surgery, University Hospital Würzburg, Würzburg, Germany
- Comprehensive Cancer Center Mainfranken, University of Würzburg, Würzburg, Germany
| | - Andreas Rosenwald
- Comprehensive Cancer Center Mainfranken, University of Würzburg, Würzburg, Germany
| | - Owen James Sansom
- CRUK Beatson Institute, Glasgow, UK
- Institute of Cancer Sciences, University of Glasgow, Glasgow, UK
| | - Martin Eilers
- Theodor Boveri Institute, Biocenter, University of Würzburg, Am Hubland, Würzburg, Germany.
- Comprehensive Cancer Center Mainfranken, University of Würzburg, Würzburg, Germany.
| | - Armin Wiegering
- Theodor Boveri Institute, Biocenter, University of Würzburg, Am Hubland, Würzburg, Germany.
- Department of General, Visceral, Vascular and Pediatric Surgery, University Hospital Würzburg, Würzburg, Germany.
- Comprehensive Cancer Center Mainfranken, University of Würzburg, Würzburg, Germany.
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80
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Janapala Y, Preiss T, Shirokikh NE. Control of Translation at the Initiation Phase During Glucose Starvation in Yeast. Int J Mol Sci 2019; 20:E4043. [PMID: 31430885 PMCID: PMC6720308 DOI: 10.3390/ijms20164043] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 08/10/2019] [Accepted: 08/15/2019] [Indexed: 12/13/2022] Open
Abstract
Glucose is one of the most important sources of carbon across all life. Glucose starvation is a key stress relevant to all eukaryotic cells. Glucose starvation responses have important implications in diseases, such as diabetes and cancer. In yeast, glucose starvation causes rapid and dramatic effects on the synthesis of proteins (mRNA translation). Response to glucose deficiency targets the initiation phase of translation by different mechanisms and with diverse dynamics. Concomitantly, translationally repressed mRNAs and components of the protein synthesis machinery may enter a variety of cytoplasmic foci, which also form with variable kinetics and may store or degrade mRNA. Much progress has been made in understanding these processes in the last decade, including with the use of high-throughput/omics methods of RNA and RNA:protein detection. This review dissects the current knowledge of yeast reactions to glucose starvation systematized by the stage of translation initiation, with the focus on rapid responses. We provide parallels to mechanisms found in higher eukaryotes, such as metazoans, for the most critical responses, and point out major remaining gaps in knowledge and possible future directions of research on translational responses to glucose starvation.
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Affiliation(s)
- Yoshika Janapala
- EMBL-Australia Collaborating Group, Department of Genome Sciences, The John Curtin School of Medical Research, The Australian National University, Canberra, ACT 2601, Australia
| | - Thomas Preiss
- EMBL-Australia Collaborating Group, Department of Genome Sciences, The John Curtin School of Medical Research, The Australian National University, Canberra, ACT 2601, Australia.
- Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia.
| | - Nikolay E Shirokikh
- EMBL-Australia Collaborating Group, Department of Genome Sciences, The John Curtin School of Medical Research, The Australian National University, Canberra, ACT 2601, Australia.
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81
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Xu Z, Hu L, Shi B, Geng S, Xu L, Wang D, Lu ZJ. Ribosome elongating footprints denoised by wavelet transform comprehensively characterize dynamic cellular translation events. Nucleic Acids Res 2019; 46:e109. [PMID: 29945224 PMCID: PMC6182183 DOI: 10.1093/nar/gky533] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Accepted: 05/31/2018] [Indexed: 02/06/2023] Open
Abstract
Translation is dynamically regulated during cell development and stress response. In order to detect actively translated open reading frames (ORFs) and dynamic cellular translation events, we have developed a computational method, RiboWave, to process ribosome profiling data. RiboWave utilizes wavelet transform to denoise the original signal by extracting 3-nt periodicity of ribosomes and precisely locate their footprint denoted as Periodic Footprint P-site (PF P-site). Such high-resolution footprint is found to capture the full track of actively elongating ribosomes, from which translational landscape can be explicitly characterized. We compare RiboWave with several published methods, like RiboTaper, ORFscore and RibORF, and found that RiboWave outperforms them in both accuracy and usage when defining actively translated ORFs. Moreover, we show that PF P-site derived by RiboWave shows superior performance in characterizing the dynamics and complexity of cellular translatome by accurately estimating the abundance of protein levels, assessing differential translation and identifying dynamic translation frameshift.
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Affiliation(s)
- Zhiyu Xu
- MOE Key Laboratory of Bioinformatics, Center for Synthetic and Systems Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Long Hu
- MOE Key Laboratory of Bioinformatics, Center for Synthetic and Systems Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Binbin Shi
- MOE Key Laboratory of Bioinformatics, Center for Synthetic and Systems Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - SiSi Geng
- MOE Key Laboratory of Bioinformatics, Center for Synthetic and Systems Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Longchen Xu
- MOE Key Laboratory of Bioinformatics, Center for Synthetic and Systems Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Dong Wang
- MOE Key Laboratory of Bioinformatics, Center for Synthetic and Systems Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Zhi J Lu
- MOE Key Laboratory of Bioinformatics, Center for Synthetic and Systems Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
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Michel AM, Kiniry SJ, O'Connor PBF, Mullan JP, Baranov PV. GWIPS-viz: 2018 update. Nucleic Acids Res 2019; 46:D823-D830. [PMID: 28977460 PMCID: PMC5753223 DOI: 10.1093/nar/gkx790] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Accepted: 08/29/2017] [Indexed: 12/15/2022] Open
Abstract
The GWIPS-viz browser (http://gwips.ucc.ie/) is an on-line genome browser which is tailored for exploring ribosome profiling (Ribo-seq) data. Since its publication in 2014, GWIPS-viz provides Ribo-seq data for an additional 14 genomes bringing the current total to 23. The integration of new Ribo-seq data has been automated thereby increasing the number of available tracks to 1792, a 10-fold increase in the last three years. The increase is particularly substantial for data derived from human sources. Following user requests, we added the functionality to download these tracks in bigWig format. We also incorporated new types of data (e.g. TCP-seq) as well as auxiliary tracks from other sources that help with the interpretation of Ribo-seq data. Improvements in the visualization of the data have been carried out particularly for bacterial genomes where the Ribo-seq data are now shown in a strand specific manner. For higher eukaryotic datasets, we provide characteristics of individual datasets using the RUST program which includes the triplet periodicity, sequencing biases and relative inferred A-site dwell times. This information can be used for assessing the quality of Ribo-seq datasets. To improve the power of the signal, we aggregate Ribo-seq data from several studies into Global aggregate tracks for each genome.
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Affiliation(s)
- Audrey M Michel
- School of Biochemistry and Cell Biology, University College Cork, Cork, Ireland
| | - Stephen J Kiniry
- School of Biochemistry and Cell Biology, University College Cork, Cork, Ireland
| | | | - James P Mullan
- School of Biochemistry and Cell Biology, University College Cork, Cork, Ireland
| | - Pavel V Baranov
- School of Biochemistry and Cell Biology, University College Cork, Cork, Ireland
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83
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ARF6 and AMAP1 are major targets of KRAS and TP53 mutations to promote invasion, PD-L1 dynamics, and immune evasion of pancreatic cancer. Proc Natl Acad Sci U S A 2019; 116:17450-17459. [PMID: 31399545 PMCID: PMC6717289 DOI: 10.1073/pnas.1901765116] [Citation(s) in RCA: 89] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Pancreatic ductal carcinomas (PDACs) have been extensively studied regarding their genomic alterations, microenvironmental intercommunication, and metabolic reprogramming. However, identification of the protein machinery of tumor cells that eventually drives malignancy as a result of driver mutations, and their associated events, is highly anticipated toward the development of precision medicine. The lack of such information regarding PDACs has hindered the elucidation of mechanisms driving malignancies, leaving them incurable. Here we demonstrated that the 2 well-known pancreatic driver mutations cooperatively activate a specific signaling pathway that promotes tumor invasion and immune evasion properties. Our results provide insights into the molecular basis by which malignancies often develop in parallel with oncogenesis and PDAC cell growth, as well as druggable targets for immunotherapies. Although KRAS and TP53 mutations are major drivers of pancreatic ductal adenocarcinoma (PDAC), the incurable nature of this cancer still remains largely elusive. ARF6 and its effector AMAP1 are often overexpressed in different cancers and regulate the intracellular dynamics of integrins and E-cadherin, thus promoting tumor invasion and metastasis when ARF6 is activated. Here we show that the ARF6–AMAP1 pathway is a major target by which KRAS and TP53 cooperatively promote malignancy. KRAS was identified to promote eIF4A-dependent ARF6 mRNA translation, which contains a quadruplex structure at its 5′-untranslated region, by inducing TEAD3 and ETV4 to suppress PDCD4; and also eIF4E-dependent AMAP1 mRNA translation, which contains a 5′-terminal oligopyrimidine-like sequence, via up-regulating mTORC1. TP53 facilitated ARF6 activation by platelet-derived growth factor (PDGF), via its known function to promote the expression of PDGF receptor β (PDGFRβ) and enzymes of the mevalonate pathway (MVP). The ARF6–AMAP1 pathway was moreover essential for PDGF-driven recycling of PD-L1, in which KRAS, TP53, eIF4A/4E-dependent translation, mTOR, and MVP were all integral. We moreover demonstrated that the mouse PDAC model KPC cells, bearing KRAS/TP53 mutations, express ARF6 and AMAP1 at high levels and that the ARF6-based pathway is closely associated with immune evasion of KPC cells. Expression of ARF6 pathway components statistically correlated with poor patient outcomes. Thus, the cooperation among eIF4A/4E-dependent mRNA translation and MVP has emerged as a link by which pancreatic driver mutations may promote tumor cell motility, PD-L1 dynamics, and immune evasion, via empowering the ARF6-based pathway and its activation by external ligands.
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84
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Kong T, Xue Y, Cencic R, Zhu X, Monast A, Fu Z, Pilon V, Sangwan V, Guiot MC, Foulkes WD, Porco JA, Park M, Pelletier J, Huang S. eIF4A Inhibitors Suppress Cell-Cycle Feedback Response and Acquired Resistance to CDK4/6 Inhibition in Cancer. Mol Cancer Ther 2019; 18:2158-2170. [PMID: 31395685 DOI: 10.1158/1535-7163.mct-19-0162] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Revised: 06/04/2019] [Accepted: 07/29/2019] [Indexed: 11/16/2022]
Abstract
CDK4/6 inhibitors are FDA-approved drugs for estrogen receptor-positive (ER+) breast cancer and are being evaluated to treat other tumor types, including KRAS-mutant non-small cell lung cancer (NSCLC). However, their clinical utility is often limited by drug resistance. Here, we sought to better understand the resistant mechanisms and help devise potential strategies to overcome this challenge. We show that treatment with CDK4/6 inhibitors in both ER+ breast cancer and KRAS-mutant NSCLC cells induces feedback upregulation of cyclin D1, CDK4, and cyclin E1, mediating drug resistance. We demonstrate that rocaglates, which preferentially target translation of key cell-cycle regulators, effectively suppress this feedback upregulation induced by CDK4/6 inhibition. Consequently, combination treatment of CDK4/6 inhibitor palbociclib with the eukaryotic initiation factor (eIF) 4A inhibitor, CR-1-31-B, is synergistic in suppressing the growth of these cancer cells in vitro and in vivo Furthermore, ER+ breast cancer and KRAS-mutant NSCLC cells that acquired resistance to palbociclib after chronic drug exposure are also highly sensitive to this combination treatment strategy. Our findings reveal a novel strategy using eIF4A inhibitors to suppress cell-cycle feedback response and to overcome resistance to CDK4/6 inhibition in cancer.
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Affiliation(s)
- Tim Kong
- Department of Biochemistry, The Rosalind and Morris Goodman Cancer Research Centre, McGill University, Montreal, Quebec, Canada
| | - Yibo Xue
- Department of Biochemistry, The Rosalind and Morris Goodman Cancer Research Centre, McGill University, Montreal, Quebec, Canada
| | - Regina Cencic
- Department of Biochemistry, The Rosalind and Morris Goodman Cancer Research Centre, McGill University, Montreal, Quebec, Canada
| | - Xianbing Zhu
- Department of Biochemistry, The Rosalind and Morris Goodman Cancer Research Centre, McGill University, Montreal, Quebec, Canada
| | - Anie Monast
- Department of Biochemistry, The Rosalind and Morris Goodman Cancer Research Centre, McGill University, Montreal, Quebec, Canada
| | - Zheng Fu
- Department of Biochemistry, The Rosalind and Morris Goodman Cancer Research Centre, McGill University, Montreal, Quebec, Canada
| | - Virginie Pilon
- Department of Biochemistry, The Rosalind and Morris Goodman Cancer Research Centre, McGill University, Montreal, Quebec, Canada
| | - Veena Sangwan
- Department of Biochemistry, The Rosalind and Morris Goodman Cancer Research Centre, McGill University, Montreal, Quebec, Canada
| | - Marie-Christine Guiot
- Department of Pathology, Montreal Neurological Hospital/Institute, McGill University Health Centre, Montreal, Quebec, Canada
| | - William D Foulkes
- Department of Human Genetics, McGill University, Montreal, Quebec, Canada.,Department of Medical Genetics, and Lady Davis Institute, Jewish General Hospital, McGill University, Montreal, Quebec, Canada.,Department of Medical Genetics and Cancer Research Program, Research Institute of the McGill University Health Centre, Montreal, Quebec, Canada
| | - John A Porco
- Department of Chemistry and Center for Molecular Discovery (BU-CMD), Boston University, Boston, Massachusetts
| | - Morag Park
- Department of Biochemistry, The Rosalind and Morris Goodman Cancer Research Centre, McGill University, Montreal, Quebec, Canada
| | - Jerry Pelletier
- Department of Biochemistry, The Rosalind and Morris Goodman Cancer Research Centre, McGill University, Montreal, Quebec, Canada
| | - Sidong Huang
- Department of Biochemistry, The Rosalind and Morris Goodman Cancer Research Centre, McGill University, Montreal, Quebec, Canada.
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85
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Waldron JA, Raza F, Le Quesne J. eIF4A alleviates the translational repression mediated by classical secondary structures more than by G-quadruplexes. Nucleic Acids Res 2019; 46:3075-3087. [PMID: 29471358 PMCID: PMC5888628 DOI: 10.1093/nar/gky108] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Accepted: 02/13/2018] [Indexed: 01/02/2023] Open
Abstract
Increased activity of the mRNA helicase eIF4A drives cellular malignancy by reprogramming cellular translation, and eIF4A activity is the direct or indirect target of many emerging cancer therapeutics. The enriched presence of (GGC)4 motifs, which have the potential to fold into two-layered G-quadruplexes, within the 5'UTRs of eIF4A-dependent mRNAs suggests that eIF4A is required for the unwinding of these structures within these eIF4A-controlled mRNAs. However, the existence of folded G-quadruplexes within cells remains controversial, and G-quadruplex folding is in direct competition with classical Watson-Crick based secondary structures. Using a combination of reverse transcription stalling assays and 7-deazaguanine incorporation experiments we find that (GGC)4 motifs preferentially form classical secondary structures rather than G-quadruplexes in full-length mRNAs. Furthermore, using translation assays with the eIF4A inhibitor hippuristanol, both in vitro and in cells, we find that eIF4A activity alleviates translational repression of mRNAs with 5'UTR classical secondary structures significantly more than those with folded G-quadruplexes. This was particularly evident in experiments using a G-quadruplex stabilizing ligand, where shifting the structural equilibrium in favour of G-quadruplex formation diminishes eIF4A-dependency. This suggests that enrichment of (GGC)4 motifs in the 5'UTRs of eIF4A-dependent mRNAs is due to the formation of stable hairpin structures rather than G-quadruplexes.
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Affiliation(s)
| | | | - John Le Quesne
- MRC Toxicology Unit, Leicester, UK.,Leicester Cancer Research Centre, University of Leicester, Leicester, UK
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86
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Proud CG. Phosphorylation and Signal Transduction Pathways in Translational Control. Cold Spring Harb Perspect Biol 2019; 11:cshperspect.a033050. [PMID: 29959191 DOI: 10.1101/cshperspect.a033050] [Citation(s) in RCA: 70] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Protein synthesis, including the translation of specific messenger RNAs (mRNAs), is regulated by extracellular stimuli such as hormones and by the levels of certain nutrients within cells. This control involves several well-understood signaling pathways and protein kinases, which regulate the phosphorylation of proteins that control the translational machinery. These pathways include the mechanistic target of rapamycin complex 1 (mTORC1), its downstream effectors, and the mitogen-activated protein (MAP) kinase (extracellular ligand-regulated kinase [ERK]) signaling pathway. This review describes the regulatory mechanisms that control translation initiation and elongation factors, in particular the effects of phosphorylation on their interactions or activities. It also discusses current knowledge concerning the impact of these control systems on the translation of specific mRNAs or subsets of mRNAs, both in physiological processes and in diseases such as cancer.
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Affiliation(s)
- Christopher G Proud
- Nutrition & Metabolism, South Australian Health & Medical Research Institute, North Terrace, Adelaide SA5000, Australia; and School of Biological Sciences, University of Adelaide, Adelaide SA5000, Australia
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87
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Zou Q, Xiao Z, Huang R, Wang X, Wang X, Zhao H, Yang X. Survey of the translation shifts in hepatocellular carcinoma with ribosome profiling. Theranostics 2019; 9:4141-4155. [PMID: 31281537 PMCID: PMC6592166 DOI: 10.7150/thno.35033] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Accepted: 04/27/2019] [Indexed: 12/11/2022] Open
Abstract
Despite the critical position of translation in the multilevel gene expression regulation program, high-resolution and genome-wide view of the landscape of RNA translation in solid tumors is still limited. Methods: With a ribosome profiling procedure optimized for solid tissue samples, we profiled the translatomes of liver tumors and their adjacent noncancerous normal liver tissues from 10 patients with hepatocellular carcinoma (HCC). A set of bioinformatics tools was then applied to these data for the mining of novel insights into the translation shifts in HCC. Results: This is the first translatome data resource for dissecting dysregulated translation in HCC at the sub-codon resolution. Based on our data, quantitative comparisons of mRNA translation rates yielded the genes and processes that were subjected to patient specific or universal dysregulations of translation efficiencies in tumors. For example, multiple proteins involved in extracellular matrix organization exhibited significant translational upregulation in tumors. We then experimentally validated the tumor-promoting functions of two such genes as examples: AGRN and VWA1. In addition, the data was also used for de novo annotation of the translatomes in tumors and normal tissues, including multiple types of novel non-canonical small ORFs, which would be a resource for further functional studies. Conclusions: The present study generates the first survey of the HCC translatome with ribosome profiling, which is an insightful data resource for dissecting the translatome shift in liver cancer, at sub-codon resolution.
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88
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Howard CM, Bearss N, Subramaniyan B, Tilley A, Sridharan S, Villa N, Fraser CS, Raman D. The CXCR4-LASP1-eIF4F Axis Promotes Translation of Oncogenic Proteins in Triple-Negative Breast Cancer Cells. Front Oncol 2019; 9:284. [PMID: 31106142 PMCID: PMC6499106 DOI: 10.3389/fonc.2019.00284] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Accepted: 03/28/2019] [Indexed: 12/19/2022] Open
Abstract
Triple-negative breast cancer (TNBC) remains clinically challenging as effective targeted therapies are lacking. In addition, patient mortality mainly results from the metastasized lesions. CXCR4 has been identified to be one of the major chemokine receptors involved in breast cancer metastasis. Previously, our lab had identified LIM and SH3 Protein 1 (LASP1) to be a key mediator in CXCR4-driven invasion. To further investigate the role of LASP1 in this process, a proteomic screen was employed and identified a novel protein-protein interaction between LASP1 and components of eukaryotic initiation 4F complex (eIF4F). We hypothesized that activation of the CXCR4-LASP1-eIF4F axis may contribute to the preferential translation of oncogenic mRNAs leading to breast cancer progression and metastasis. To test this hypothesis, we first confirmed that the gene expression of CXCR4, LASP1, and eIF4A are upregulated in invasive breast cancer. Moreover, we demonstrate that LASP1 associated with eIF4A in a CXCL12-dependent manner via a proximity ligation assay. We then confirmed this finding, and the association of LASP1 with eIF4B via co-immunoprecipitation assays. Furthermore, we show that LASP1 can interact with eIF4A and eIF4B through a GST-pulldown approach. Activation of CXCR4 signaling increased the translation of oncoproteins downstream of eIF4A. Interestingly, genetic silencing of LASP1 interrupted the ability of eIF4A to translate oncogenic mRNAs into oncoproteins. This impaired ability of eIF4A was confirmed by a previously established 5′UTR luciferase reporter assay. Finally, lack of LASP1 sensitizes 231S cells to pharmacological inhibition of eIF4A by Rocaglamide A as evident through BIRC5 expression. Overall, our work identified the CXCR4-LASP1 axis to be a novel mediator in oncogenic protein translation. Thus, our axis of study represents a potential target for future TNBC therapies.
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Affiliation(s)
- Cory M Howard
- Department of Cancer Biology, University of Toledo Health Science Campus, Toledo, OH, United States
| | - Nicole Bearss
- Department of Cancer Biology, University of Toledo Health Science Campus, Toledo, OH, United States
| | - Boopathi Subramaniyan
- Department of Cancer Biology, University of Toledo Health Science Campus, Toledo, OH, United States
| | - Augustus Tilley
- Department of Cancer Biology, University of Toledo Health Science Campus, Toledo, OH, United States
| | - Sangita Sridharan
- Department of Cancer Biology, University of Toledo Health Science Campus, Toledo, OH, United States
| | - Nancy Villa
- Department of Molecular and Cellular Biology, University of California, Davis, Davis, CA, United States
| | - Christopher S Fraser
- Department of Molecular and Cellular Biology, University of California, Davis, Davis, CA, United States
| | - Dayanidhi Raman
- Department of Cancer Biology, University of Toledo Health Science Campus, Toledo, OH, United States
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89
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Schuster SL, Hsieh AC. The Untranslated Regions of mRNAs in Cancer. Trends Cancer 2019; 5:245-262. [PMID: 30961831 PMCID: PMC6465068 DOI: 10.1016/j.trecan.2019.02.011] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 02/23/2019] [Accepted: 02/25/2019] [Indexed: 12/19/2022]
Abstract
The 5' and 3' untranslated regions (UTRs) regulate crucial aspects of post-transcriptional gene regulation that are necessary for the maintenance of cellular homeostasis. When these processes go awry through mutation or misexpression of certain regulatory elements, the subsequent deregulation of oncogenic gene expression can drive or enhance cancer pathogenesis. Although the number of known cancer-related mutations in UTR regulatory elements has recently increased markedly as a result of advances in whole-genome sequencing, little is known about how the majority of these genetic aberrations contribute functionally to disease. In this review we explore the regulatory functions of UTRs, how they are co-opted in cancer, new technologies to interrogate cancerous UTRs, and potential therapeutic opportunities stemming from these regions.
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Affiliation(s)
- Samantha L Schuster
- Molecular and Cellular Biology, University of Washington, Seattle, WA 98195, USA; Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, WA, 98109, USA
| | - Andrew C Hsieh
- Molecular and Cellular Biology, University of Washington, Seattle, WA 98195, USA; Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, WA, 98109, USA; School of Medicine and Genome Sciences, University of Washington, Seattle, WA 98195, USA.
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90
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Palangat M, Anastasakis DG, Fei DL, Lindblad KE, Bradley R, Hourigan CS, Hafner M, Larson DR. The splicing factor U2AF1 contributes to cancer progression through a noncanonical role in translation regulation. Genes Dev 2019; 33:482-497. [PMID: 30842218 PMCID: PMC6499322 DOI: 10.1101/gad.319590.118] [Citation(s) in RCA: 60] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Accepted: 02/15/2019] [Indexed: 01/07/2023]
Abstract
Palangat et al. uncovered a noncanonical function of U2AF1, showing that it directly binds mature mRNA in the cytoplasm and negatively regulates mRNA translation. Somatic mutations in the genes encoding components of the spliceosome occur frequently in human neoplasms, including myeloid dysplasias and leukemias, and less often in solid tumors. One of the affected factors, U2AF1, is involved in splice site selection, and the most common change, S34F, alters a conserved nucleic acid-binding domain, recognition of the 3′ splice site, and alternative splicing of many mRNAs. However, the role that this mutation plays in oncogenesis is still unknown. Here, we uncovered a noncanonical function of U2AF1, showing that it directly binds mature mRNA in the cytoplasm and negatively regulates mRNA translation. This splicing-independent role of U2AF1 is altered by the S34F mutation, and polysome profiling indicates that the mutation affects translation of hundreds of mRNA. One functional consequence is increased synthesis of the secreted chemokine interleukin 8, which contributes to metastasis, inflammation, and cancer progression in mice and humans.
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Affiliation(s)
- Murali Palangat
- Laboratory of Receptor Biology and Gene Expression, National Cancer Insitute, National Institutes of Health, Bethesda, Maryland 20892, USA
| | - Dimitrios G Anastasakis
- National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA
| | | | - Katherine E Lindblad
- Laboratory of Myeloid Malignancies, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland 20892, USA
| | - Robert Bradley
- Computational Biology Program, Public Health Sciences and Biological Sciences, Fred Hutchinson Cancer Center, Seattle, Washington 98109, USA
| | - Christopher S Hourigan
- Laboratory of Myeloid Malignancies, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland 20892, USA
| | - Markus Hafner
- National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA
| | - Daniel R Larson
- Laboratory of Receptor Biology and Gene Expression, National Cancer Insitute, National Institutes of Health, Bethesda, Maryland 20892, USA
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91
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Iwasaki S, Iwasaki W, Takahashi M, Sakamoto A, Watanabe C, Shichino Y, Floor SN, Fujiwara K, Mito M, Dodo K, Sodeoka M, Imataka H, Honma T, Fukuzawa K, Ito T, Ingolia NT. The Translation Inhibitor Rocaglamide Targets a Bimolecular Cavity between eIF4A and Polypurine RNA. Mol Cell 2019; 73:738-748.e9. [PMID: 30595437 PMCID: PMC6386617 DOI: 10.1016/j.molcel.2018.11.026] [Citation(s) in RCA: 109] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Revised: 07/23/2018] [Accepted: 11/15/2018] [Indexed: 01/17/2023]
Abstract
A class of translation inhibitors, exemplified by the natural product rocaglamide A (RocA), isolated from Aglaia genus plants, exhibits antitumor activity by clamping eukaryotic translation initiation factor 4A (eIF4A) onto polypurine sequences in mRNAs. This unusual inhibitory mechanism raises the question of how the drug imposes sequence selectivity onto a general translation factor. Here, we determined the crystal structure of the human eIF4A1⋅ATP analog⋅RocA⋅polypurine RNA complex. RocA targets the "bi-molecular cavity" formed characteristically by eIF4A1 and a sharply bent pair of consecutive purines in the RNA. Natural amino acid substitutions found in Aglaia eIF4As changed the cavity shape, leading to RocA resistance. This study provides an example of an RNA-sequence-selective interfacial inhibitor fitting into the space shaped cooperatively by protein and RNA with specific sequences.
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Affiliation(s)
- Shintaro Iwasaki
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA; RNA Systems Biochemistry Laboratory, RIKEN Cluster for Pioneering Research, Wako, Saitama 351-0198, Japan; Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Tokyo 277-8561, Japan.
| | - Wakana Iwasaki
- Laboratory for Translation Structural Biology, RIKEN Center for Biosystems Dynamics Research, Tsurumi-ku, Yokohama 230-0045, Japan; Division of Structural and Synthetic Biology, RIKEN Center for Life Science Technologies, Tsurumi-ku, Yokohama 230-0045, Japan
| | - Mari Takahashi
- Laboratory for Translation Structural Biology, RIKEN Center for Biosystems Dynamics Research, Tsurumi-ku, Yokohama 230-0045, Japan; Division of Structural and Synthetic Biology, RIKEN Center for Life Science Technologies, Tsurumi-ku, Yokohama 230-0045, Japan
| | - Ayako Sakamoto
- Laboratory for Translation Structural Biology, RIKEN Center for Biosystems Dynamics Research, Tsurumi-ku, Yokohama 230-0045, Japan; Division of Structural and Synthetic Biology, RIKEN Center for Life Science Technologies, Tsurumi-ku, Yokohama 230-0045, Japan
| | - Chiduru Watanabe
- Division of Structural and Synthetic Biology, RIKEN Center for Life Science Technologies, Tsurumi-ku, Yokohama 230-0045, Japan; Laboratory for Structure-Based Molecular Design, RIKEN Center for Biosystems Dynamics Research, Tsurumi-ku, Yokohama 230-0045, Japan
| | - Yuichi Shichino
- RNA Systems Biochemistry Laboratory, RIKEN Cluster for Pioneering Research, Wako, Saitama 351-0198, Japan
| | - Stephen N Floor
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA; Department of Cell and Tissue Biology, University of California, San Francisco, San Francisco, CA 94143, USA; Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Koichi Fujiwara
- Synthetic Organic Chemistry Laboratory, RIKEN Cluster for Pioneering Research, Wako, Saitama 351-0198, Japan
| | - Mari Mito
- RNA Systems Biochemistry Laboratory, RIKEN Cluster for Pioneering Research, Wako, Saitama 351-0198, Japan
| | - Kosuke Dodo
- Synthetic Organic Chemistry Laboratory, RIKEN Cluster for Pioneering Research, Wako, Saitama 351-0198, Japan; AMED-CREST, Japan Agency for Medical Research and Development, Wako, Saitama 351-0198, Japan; RIKEN Center for Sustainable Resource Science, Wako, Saitama 351-0198, Japan
| | - Mikiko Sodeoka
- Synthetic Organic Chemistry Laboratory, RIKEN Cluster for Pioneering Research, Wako, Saitama 351-0198, Japan; AMED-CREST, Japan Agency for Medical Research and Development, Wako, Saitama 351-0198, Japan; RIKEN Center for Sustainable Resource Science, Wako, Saitama 351-0198, Japan
| | - Hiroaki Imataka
- Graduate School of Engineering, University of Hyogo, Himeji, Hyogo 671-2201, Japan
| | - Teruki Honma
- Division of Structural and Synthetic Biology, RIKEN Center for Life Science Technologies, Tsurumi-ku, Yokohama 230-0045, Japan; Laboratory for Structure-Based Molecular Design, RIKEN Center for Biosystems Dynamics Research, Tsurumi-ku, Yokohama 230-0045, Japan
| | - Kaori Fukuzawa
- School of Pharmacy and Pharmaceutical Sciences, Hoshi University, Shinagawa, Tokyo 142-8501, Japan
| | - Takuhiro Ito
- Laboratory for Translation Structural Biology, RIKEN Center for Biosystems Dynamics Research, Tsurumi-ku, Yokohama 230-0045, Japan; Division of Structural and Synthetic Biology, RIKEN Center for Life Science Technologies, Tsurumi-ku, Yokohama 230-0045, Japan.
| | - Nicholas T Ingolia
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA.
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92
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Itoua Maïga R, Cencic R, Chu J, Waller DD, Brown LE, Devine WG, Zhang W, Sebag M, Porco JA, Pelletier J. Oxo-aglaiastatin-Mediated Inhibition of Translation Initiation. Sci Rep 2019; 9:1265. [PMID: 30718665 PMCID: PMC6361980 DOI: 10.1038/s41598-018-37666-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Accepted: 12/10/2018] [Indexed: 11/22/2022] Open
Abstract
Translation is a highly regulated process that is perturbed in human cancers, often through activation of the PI3K/mTOR pathway which impacts directly on the ribosome recruitment phase of translation initiation. While significant research has focused on “drugging” components of the PI3K/mTOR network, efforts have also been directed towards inhibiting eukaryotic initiation factor (eIF) 4F-dependent translation. Small molecule inhibitors of this complex have been identified, characterized, and used to validate the rationale of targeting this step to curtail tumor cell growth and modulate chemotherapy response. One such class of compounds are the rocaglates, secondary metabolites from the plant genus Aglaia, which target the RNA helicase subunit of eIF4F, eIF4A. Here we explore the ability of synthetic derivatives of aglaiastatins and an aglaroxin derivative to target the translation process in vitro and in vivo and find the synthetic derivative oxo-aglaiastatin to possess such activity. Oxo-aglaiastatin inhibited translation in vitro and in vivo and synergized with doxorubicin, ABT-199 (a Bcl-2 antagonist), and dexamethasone when tested on hematological cancer cells. The biological activity of oxo-aglaiastatin was shown to be a consequence of inhibiting eIF4A1 activity.
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Affiliation(s)
- Rayelle Itoua Maïga
- Department of Biochemistry, McGill University, Montreal, Québec, H3G 1Y6, Canada
| | - Regina Cencic
- Department of Biochemistry, McGill University, Montreal, Québec, H3G 1Y6, Canada
| | - Jennifer Chu
- Department of Biochemistry, McGill University, Montreal, Québec, H3G 1Y6, Canada
| | - Daniel D Waller
- Department of Medicine, McGill University, Montreal, Québec, H3G 1Y6, Canada
| | - Lauren E Brown
- Department of Chemistry and Center for Molecular Discovery (BU-CMD), Boston University, Boston, MA, 02215, USA
| | - William G Devine
- Department of Chemistry and Center for Molecular Discovery (BU-CMD), Boston University, Boston, MA, 02215, USA
| | - Wenhan Zhang
- Department of Chemistry and Center for Molecular Discovery (BU-CMD), Boston University, Boston, MA, 02215, USA
| | - Michael Sebag
- Department of Medicine, McGill University, Montreal, Québec, H3G 1Y6, Canada
| | - John A Porco
- Department of Chemistry and Center for Molecular Discovery (BU-CMD), Boston University, Boston, MA, 02215, USA
| | - Jerry Pelletier
- Department of Biochemistry, McGill University, Montreal, Québec, H3G 1Y6, Canada. .,Department of Oncology, McGill University, Montreal, Québec, H3G 1Y6, Canada. .,Rosalind & Morris Goodman Cancer Research Centre, McGill University, Montreal, Québec, H3A 1A3, Canada.
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93
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Zennami K, Choi SM, Liao R, Li Y, Dinalankara W, Marchionni L, Rafiqi FH, Kurozumi A, Hatano K, Lupold SE. PDCD4 Is an Androgen-Repressed Tumor Suppressor that Regulates Prostate Cancer Growth and Castration Resistance. Mol Cancer Res 2019; 17:618-627. [PMID: 30518628 PMCID: PMC6359980 DOI: 10.1158/1541-7786.mcr-18-0837] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Revised: 10/09/2018] [Accepted: 11/21/2018] [Indexed: 12/11/2022]
Abstract
Androgen receptor (AR) transcriptional activity contributes to prostate cancer development and castration resistance. The growth and survival pathways driven by AR remain incompletely defined. Here, we found PDCD4 to be a new target of AR signaling and a potent regulator of prostate cancer cell growth, survival, and castration resistance. The 3' untranslated region of PDCD4 is directly targeted by the androgen-induced miRNA, miR-21. Androgen treatment suppressed PDCD4 expression in a dose responsive and miR-21-dependent manner. Correspondingly, AR inhibition dose-responsively induced PDCD4 expression. Using data from prostate cancer tissue samples in The Cancer Genome Atlas (TCGA), we found a significant and inverse correlation between miR-21 and PDCD4 mRNA and protein levels. Higher Gleason grade tumors exhibited significantly higher levels of miR-21 and significantly lower levels of PDCD4 mRNA and protein. PDCD4 knockdown enhanced androgen-dependent cell proliferation and cell-cycle progression, inhibited apoptosis, and was sufficient to drive androgen-independent growth. On the other hand, PDCD4 overexpression inhibited miR-21-mediated growth and androgen independence. The stable knockdown of PDCD4 in androgen-dependent prostate cancer cells enhanced subcutaneous tumor take rate in vivo, accelerated tumor growth, and was sufficient for castration-resistant tumor growth. IMPLICATIONS: This study provides the first evidence that PDCD4 is an androgen-suppressed protein capable of regulating prostate cancer cell proliferation, apoptosis, and castration resistance. These results uncover miR-21 and PDCD4-regulated pathways as potential new targets for castration-resistant prostate cancer.
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Affiliation(s)
- Kenji Zennami
- Department of Urology, The James Buchanan Brady Urologic Institute, Johns Hopkins School of Medicine, Baltimore, Maryland
| | - Su Mi Choi
- Department of Urology, The James Buchanan Brady Urologic Institute, Johns Hopkins School of Medicine, Baltimore, Maryland
| | - Ross Liao
- Department of Urology, The James Buchanan Brady Urologic Institute, Johns Hopkins School of Medicine, Baltimore, Maryland
| | - Ying Li
- Department of Urology, The James Buchanan Brady Urologic Institute, Johns Hopkins School of Medicine, Baltimore, Maryland
| | - Wikum Dinalankara
- Department of Oncology, Sidney Kimmel Comprehensive Cancer Center, School of Medicine, Johns Hopkins University, Baltimore, Maryland
| | - Luigi Marchionni
- Department of Oncology, Sidney Kimmel Comprehensive Cancer Center, School of Medicine, Johns Hopkins University, Baltimore, Maryland
| | - Fatema H Rafiqi
- Department of Urology, The James Buchanan Brady Urologic Institute, Johns Hopkins School of Medicine, Baltimore, Maryland
| | - Akira Kurozumi
- Department of Urology, The James Buchanan Brady Urologic Institute, Johns Hopkins School of Medicine, Baltimore, Maryland
| | - Koji Hatano
- Department of Urology, The James Buchanan Brady Urologic Institute, Johns Hopkins School of Medicine, Baltimore, Maryland
| | - Shawn E Lupold
- Department of Urology, The James Buchanan Brady Urologic Institute, Johns Hopkins School of Medicine, Baltimore, Maryland.
- Department of Oncology, Sidney Kimmel Comprehensive Cancer Center, School of Medicine, Johns Hopkins University, Baltimore, Maryland
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94
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Chen R, Zhu M, Chaudhari RR, Robles O, Chen Y, Skillern W, Qin Q, Wierda WG, Zhang S, Hull KG, Romo D, Plunkett W. Creating novel translation inhibitors to target pro-survival proteins in chronic lymphocytic leukemia. Leukemia 2019; 33:1663-1674. [DOI: 10.1038/s41375-018-0364-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Revised: 10/30/2018] [Accepted: 12/03/2018] [Indexed: 12/20/2022]
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95
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Murat P, Marsico G, Herdy B, Ghanbarian AT, Portella G, Balasubramanian S. RNA G-quadruplexes at upstream open reading frames cause DHX36- and DHX9-dependent translation of human mRNAs. Genome Biol 2018; 19:229. [PMID: 30591072 PMCID: PMC6307142 DOI: 10.1186/s13059-018-1602-2] [Citation(s) in RCA: 94] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Accepted: 12/04/2018] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND RNA secondary structures in the 5'-untranslated regions (5'-UTR) of mRNAs are key to the post-transcriptional regulation of gene expression. While it is evident that non-canonical Hoogsteen-paired G-quadruplex (rG4) structures somehow contribute to the regulation of translation initiation, the nature and extent of human mRNAs that are regulated by rG4s is not known. Here, we provide new insights into a mechanism by which rG4 formation modulates translation. RESULTS Using transcriptome-wide ribosome profiling, we identify rG4-driven mRNAs in HeLa cells and reveal that rG4s in the 5'-UTRs of inefficiently translated mRNAs associate with high ribosome density and the translation of repressive upstream open reading frames (uORF). We demonstrate that depletion of the rG4-unwinding helicases DHX36 and DHX9 promotes translation of rG4-associated uORFs while reducing the translation of coding regions for transcripts that comprise proto-oncogenes, transcription factors and epigenetic regulators. Transcriptome-wide identification of DHX9 binding sites shows that reduced translation is mediated through direct physical interaction between the helicase and its rG4 substrate. CONCLUSION This study identifies human mRNAs whose translation efficiency is modulated by the DHX36- and DHX9-dependent folding/unfolding of rG4s within their 5'-UTRs. We reveal a previously unknown mechanism for translation regulation in which unresolved rG4s within 5'-UTRs promote 80S ribosome formation on upstream start codons, causing inhibition of translation of the downstream main open reading frames. Our findings suggest that the interaction of helicases with rG4s could be targeted for future therapeutic intervention.
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Affiliation(s)
- Pierre Murat
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK
- Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Robinson Way, Cambridge, CB2 0RE, UK
| | - Giovanni Marsico
- Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Robinson Way, Cambridge, CB2 0RE, UK
| | - Barbara Herdy
- Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Robinson Way, Cambridge, CB2 0RE, UK
| | - Avazeh T Ghanbarian
- Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Robinson Way, Cambridge, CB2 0RE, UK
| | - Guillem Portella
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK
| | - Shankar Balasubramanian
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK.
- Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Robinson Way, Cambridge, CB2 0RE, UK.
- School of Clinical Medicine, University of Cambridge, Cambridge, CB2 0SP, UK.
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96
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Translational control of tumor immune escape via the eIF4F-STAT1-PD-L1 axis in melanoma. Nat Med 2018; 24:1877-1886. [PMID: 30374200 DOI: 10.1038/s41591-018-0217-1] [Citation(s) in RCA: 162] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2018] [Accepted: 08/24/2018] [Indexed: 01/05/2023]
Abstract
Preventing the immune escape of tumor cells by blocking inhibitory checkpoints, such as the interaction between programmed death ligand-1 (PD-L1) and programmed death-1 (PD-1) receptor, is a powerful anticancer approach. However, many patients do not respond to checkpoint blockade. Tumor PD-L1 expression is a potential efficacy biomarker, but the complex mechanisms underlying its regulation are not completely understood. Here, we show that the eukaryotic translation initiation complex, eIF4F, which binds the 5' cap of mRNAs, regulates the surface expression of interferon-γ-induced PD-L1 on cancer cells by regulating translation of the mRNA encoding the signal transducer and activator of transcription 1 (STAT1) transcription factor. eIF4F complex formation correlates with response to immunotherapy in human melanoma. Pharmacological inhibition of eIF4A, the RNA helicase component of eIF4F, elicits powerful antitumor immune-mediated effects via PD-L1 downregulation. Thus, eIF4A inhibitors, in development as anticancer drugs, may also act as cancer immunotherapies.
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97
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Peters TL, Tillotson J, Yeomans AM, Wilmore S, Lemm E, Jiménez-Romero C, Amador LA, Li L, Amin AD, Pongtornpipat P, Zerio CJ, Ambrose AJ, Paine-Murrieta G, Greninger P, Vega F, Benes CH, Packham G, Rodríguez AD, Chapman E, Schatz JH. Target-Based Screening against eIF4A1 Reveals the Marine Natural Product Elatol as a Novel Inhibitor of Translation Initiation with In Vivo Antitumor Activity. Clin Cancer Res 2018; 24:4256-4270. [PMID: 29844128 PMCID: PMC6500731 DOI: 10.1158/1078-0432.ccr-17-3645] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2017] [Revised: 04/20/2018] [Accepted: 05/21/2018] [Indexed: 12/26/2022]
Abstract
Purpose: The DEAD-box RNA helicase eIF4A1 carries out the key enzymatic step of cap-dependent translation initiation and is a well-established target for cancer therapy, but no drug against it has entered evaluation in patients. We identified and characterized a natural compound with broad antitumor activities that emerged from the first target-based screen to identify novel eIF4A1 inhibitors.Experimental Design: We tested potency and specificity of the marine compound elatol versus eIF4A1 ATPase activity. We also assessed eIF4A1 helicase inhibition, binding between the compound and the target including binding site mutagenesis, and extensive mechanistic studies in cells. Finally, we determined maximum tolerated dosing in vivo and assessed activity against xenografted tumors.Results: We found elatol is a specific inhibitor of ATP hydrolysis by eIF4A1 in vitro with broad activity against multiple tumor types. The compound inhibits eIF4A1 helicase activity and binds the target with unexpected 2:1 stoichiometry at key sites in its helicase core. Sensitive tumor cells suffer acute loss of translationally regulated proteins, leading to growth arrest and apoptosis. In contrast to other eIF4A1 inhibitors, elatol induces markers of an integrated stress response, likely an off-target effect, but these effects do not mediate its cytotoxic activities. Elatol is less potent in vitro than the well-studied eIF4A1 inhibitor silvestrol but is tolerated in vivo at approximately 100× relative dosing, leading to significant activity against lymphoma xenografts.Conclusions: Elatol's identification as an eIF4A1 inhibitor with in vivo antitumor activities provides proof of principle for target-based screening against this highly promising target for cancer therapy. Clin Cancer Res; 24(17); 4256-70. ©2018 AACR.
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Affiliation(s)
- Tara L Peters
- Sheila and David Fuente Graduate Program in Cancer Biology, University of Miami, Miami, Florida
- Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, Florida
| | | | - Alison M Yeomans
- Somers Cancer Science Building, University of Southampton, Southampton, United Kingdom
| | - Sarah Wilmore
- University of Southampton, Southampton, United Kingdom
| | - Elizabeth Lemm
- Cancer Research UK Centre, University of Southampton, Southampton, United Kingdom
| | - Carlos Jiménez-Romero
- Molecular Sciences Research Center, University of Puerto Rico, San Juan, Puerto Rico
| | - Luis A Amador
- Molecular Sciences Research Center, University of Puerto Rico, San Juan, Puerto Rico
| | - Lingxiao Li
- Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, Florida
- Division of Hematology, Department of Medicine, University of Miami Miller School of Medicine, Miami, Florida
| | - Amit D Amin
- Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, Florida
- Division of Hematology, Department of Medicine, University of Miami Miller School of Medicine, Miami, Florida
| | | | | | | | | | - Patricia Greninger
- Center for Cancer Research, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts
| | - Francisco Vega
- Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, Florida
- Division of Hematopathology, Department of Pathology, University of Miami Miller School of Medicine, Miami, Florida
| | - Cyril H Benes
- Center for Cancer Research, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts
| | - Graham Packham
- Cancer Research UK Centre, University of Southampton, Southampton, United Kingdom
| | - Abimael D Rodríguez
- Molecular Sciences Research Center, University of Puerto Rico, San Juan, Puerto Rico
| | - Eli Chapman
- College of Pharmacy, University of Arizona, Tucson, Arizona.
| | - Jonathan H Schatz
- Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, Florida.
- Division of Hematology, Department of Medicine, University of Miami Miller School of Medicine, Miami, Florida
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98
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Samson J, Cronin S, Dean K. BC200 (BCYRN1) - The shortest, long, non-coding RNA associated with cancer. Noncoding RNA Res 2018; 3:131-143. [PMID: 30175286 PMCID: PMC6114260 DOI: 10.1016/j.ncrna.2018.05.003] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Revised: 05/14/2018] [Accepted: 05/17/2018] [Indexed: 12/22/2022] Open
Abstract
With the discovery that the level of RNA synthesis in human cells far exceeds what is required to express protein-coding genes, there has been a concerted scientific effort to identify, catalogue and uncover the biological functions of the non-coding transcriptome. Long, non-coding RNAs (lncRNAs) are a diverse group of RNAs with equally wide-ranging biological roles in the cell. An increasing number of studies have reported alterations in the expression of lncRNAs in various cancers, although unravelling how they contribute specifically to the disease is a bigger challenge. Originally described as a brain-specific, non-coding RNA, BC200 (BCYRN1) is a 200-nucleotide, predominantly cytoplasmic lncRNA that has been linked to neurodegenerative disease and several types of cancer. Here we summarise what is known about BC200, primarily from studies in neuronal systems, before turning to a review of recent work that aims to understand how this lncRNA contributes to cancer initiation, progression and metastasis, along with its possible clinical utility as a biomarker or therapeutic target.
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Affiliation(s)
| | | | - K. Dean
- School of Biochemistry and Cell Biology, Western Gateway Building, University College Cork, Cork, Ireland
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99
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Lezina L, Spriggs RV, Beck D, Jones C, Dudek KM, Bzura A, Jones GDD, Packham G, Willis AE, Wagner SD. CD40L/IL-4-stimulated CLL demonstrates variation in translational regulation of DNA damage response genes including ATM. Blood Adv 2018; 2:1869-1881. [PMID: 30082430 PMCID: PMC6093746 DOI: 10.1182/bloodadvances.2017015560] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2017] [Accepted: 07/06/2018] [Indexed: 02/07/2023] Open
Abstract
CD40L/interleukin-4 (IL-4) stimulation occurs in vivo in the tumor microenvironment and induces global translation to varying degrees in individuals with chronic lymphocytic leukemia (CLL) in vitro. However, the implications of CD40L/IL-4 for the translation of specific genes is not known. To determine the most highly translationally regulated genes in response to CD40L/IL-4, we carried out ribosome profiling, a next-generation sequencing method. Significant differences in the translational efficiency of DNA damage response genes, specifically ataxia-telangiectasia-mutated kinase (ATM) and the MRE11/RAD50/NBN (MRN) complex, were observed between patients, suggesting different patterns of translational regulation. We confirmed associations between CD40L/IL-4 response and baseline ATM levels, induction of ATM, and phosphorylation of the ATM targets, p53 and H2AX. X-irradiation was used to demonstrate that CD40L/IL-4 stimulation tended to improve DNA damage repair. Baseline ATM levels, independent of the presence of 11q deletion, correlated with overall survival (OS). Overall, we suggest that there are individual differences in translation of specific genes, including ATM, in response to CD40L/IL-4 and that these interpatient differences might be clinically important.
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Affiliation(s)
- Larissa Lezina
- Leicester Cancer Research Centre and
- Ernest and Helen Scott Haematology Research Institute, University of Leicester, Leicester, United Kingdom
| | - Ruth V Spriggs
- Medical Research Council Toxicology Unit, Leicester, United Kingdom; and
| | - Daniel Beck
- Leicester Cancer Research Centre and
- Ernest and Helen Scott Haematology Research Institute, University of Leicester, Leicester, United Kingdom
| | - Carolyn Jones
- Medical Research Council Toxicology Unit, Leicester, United Kingdom; and
| | - Kate M Dudek
- Medical Research Council Toxicology Unit, Leicester, United Kingdom; and
| | | | | | - Graham Packham
- Cancer Research UK Centre, Cancer Sciences Unit, Faculty of Medicine, University of Southampton, Southampton, United Kingdom
| | - Anne E Willis
- Medical Research Council Toxicology Unit, Leicester, United Kingdom; and
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100
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Chu J, Pelletier J. Therapeutic Opportunities in Eukaryotic Translation. Cold Spring Harb Perspect Biol 2018; 10:cshperspect.a032995. [PMID: 29440069 DOI: 10.1101/cshperspect.a032995] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The ability to block biological processes with selective small molecules provides advantages distinct from most other experimental approaches. These include rapid time to onset, swift reversibility, ability to probe activities in manners that cannot be accessed by genetic means, and the potential to be further developed as therapeutic agents. Small molecule inhibitors can also be used to alter expression and activity without affecting the stoichiometry of interacting partners. These tenets have been especially evident in the field of translation. Small molecule inhibitors were instrumental in enabling investigators to capture short-lived complexes and characterize specific steps of protein synthesis. In addition, several drugs that are the mainstay of modern antimicrobial drug therapy are potent inhibitors of prokaryotic translation. Currently, there is much interest in targeting eukaryotic translation as decades of research have revealed that deregulated protein synthesis in cancer cells represents a targetable vulnerability. In addition to being potential therapeutics, small molecules that manipulate translation have also been shown to influence cognitive processes such as memory. In this review, we focus on small molecule modulators that target the eukaryotic translation initiation apparatus and provide an update on their potential application to the treatment of disease.
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Affiliation(s)
- Jennifer Chu
- Department of Biochemistry, McGill University, Montreal, Quebec H3G 1Y6, Canada
| | - Jerry Pelletier
- Department of Biochemistry, McGill University, Montreal, Quebec H3G 1Y6, Canada.,Department of Oncology, McGill University, Montreal, Quebec H3G 1Y6, Canada.,Rosalind and Morris Goodman Cancer Research Center, McGill University, Montreal, Quebec H3G 1Y6, Canada
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