1
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Piecyk M, Fauvre J, Duret C, Chaveroux C, Ferraro-Peyret C. SUrface SEnsing of Translation (SUnSET), a Method Based on Western Blot Assessing Protein Synthesis Rates in vitro. Bio Protoc 2024; 14:e4933. [PMID: 38379826 PMCID: PMC10875356 DOI: 10.21769/bioprotoc.4933] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Revised: 12/21/2023] [Accepted: 01/10/2024] [Indexed: 02/22/2024] Open
Abstract
As the most energy- and metabolite-consuming process, protein synthesis is under the control of several intrinsic and extrinsic factors that determine its fine-tuning to the cellular microenvironment. Consequently, variations in protein synthesis rates occur under various physiological and pathological conditions, enabling an adaptive response by the cell. For example, global protein synthesis increases upon mitogenic factors to support biomass generation and cell proliferation, while exposure to low concentrations of oxygen or nutrients require translational repression and reprogramming to avoid energy depletion and cell death. To assess fluctuations in protein synthesis rates, radioactive isotopes or radiolabeled amino acids are often used. Although highly sensitive, these techniques involve the use of potentially toxic radioactive compounds and require specific materials and processes for the use and disposal of these molecules. The development of alternative, non-radioactive methods that can be easily and safely implemented in laboratories has therefore been encouraged to avoid handling radioactivity. In this context, the SUrface SEnsing of Translation (SUnSET) method, based on the classical western blot technique, was developed by Schmidt et al. in 2009. The SUnSET is nowadays recognized as a simple alternative to radioactive methods assessing protein synthesis rates. Key features • As a structural analogue of aminoacyl-transfer RNA, puromycin incorporates into the elongating peptide chain. • Detection of puromycin-labeled peptides by western blotting reflects translation rates without the need for radioactive isotopes. • The protocol described here for in vitro applications is derived from the SUnSET method originally published by Schmidt et al. (2009).
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Affiliation(s)
- Marie Piecyk
- Centre de Recherche en Cancérologie de Lyon,
INSERM U1052, CNRS 5286, Centre Léon Bérard, Université de
Lyon, Université Claude Bernard Lyon 1, Lyon, France
| | - Joëlle Fauvre
- Centre de Recherche en Cancérologie de Lyon,
INSERM U1052, CNRS 5286, Centre Léon Bérard, Université de
Lyon, Université Claude Bernard Lyon 1, Lyon, France
| | - Cédric Duret
- Centre de Recherche en Cancérologie de Lyon,
INSERM U1052, CNRS 5286, Centre Léon Bérard, Université de
Lyon, Université Claude Bernard Lyon 1, Lyon, France
| | - Cédric Chaveroux
- Centre de Recherche en Cancérologie de Lyon,
INSERM U1052, CNRS 5286, Centre Léon Bérard, Université de
Lyon, Université Claude Bernard Lyon 1, Lyon, France
| | - Carole Ferraro-Peyret
- Centre de Recherche en Cancérologie de Lyon,
INSERM U1052, CNRS 5286, Centre Léon Bérard, Université de
Lyon, Université Claude Bernard Lyon 1, Lyon, France
- Hospices Civils de Lyon, Laboratoire AURAGEN,
Hôpital E. Herriot, Lyon, France
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2
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Cencic R, Im YK, Naineni SK, Moustafa-Kamal M, Jovanovic P, Sabourin V, Annis MG, Robert F, Schmeing TM, Koromilas A, Paquet M, Teodoro JG, Huang S, Siegel PM, Topisirovic I, Ursini-Siegel J, Pelletier J. A second-generation eIF4A RNA helicase inhibitor exploits translational reprogramming as a vulnerability in triple-negative breast cancer. Proc Natl Acad Sci U S A 2024; 121:e2318093121. [PMID: 38232291 PMCID: PMC10823175 DOI: 10.1073/pnas.2318093121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Accepted: 12/15/2023] [Indexed: 01/19/2024] Open
Abstract
In this study, we aimed to address the current limitations of therapies for macro-metastatic triple-negative breast cancer (TNBC) and provide a therapeutic lead that overcomes the high degree of heterogeneity associated with this disease. Specifically, we focused on well-documented but clinically underexploited cancer-fueling perturbations in mRNA translation as a potential therapeutic vulnerability. We therefore developed an orally bioavailable rocaglate-based molecule, MG-002, which hinders ribosome recruitment and scanning via unscheduled and non-productive RNA clamping by the eukaryotic translation initiation factor (eIF) 4A RNA helicase. We demonstrate that MG-002 potently inhibits mRNA translation and primary TNBC tumor growth without causing overt toxicity in mice. Importantly, given that metastatic spread is a major cause of mortality in TNBC, we show that MG-002 attenuates metastasis in pre-clinical models. We report on MG-002, a rocaglate that shows superior properties relative to existing eIF4A inhibitors in pre-clinical models. Our study also paves the way for future clinical trials exploring the potential of MG-002 in TNBC and other oncological indications.
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Affiliation(s)
- Regina Cencic
- Department of Biochemistry, McGill University, Montreal, QC H3G 1Y6, Canada
- Rosalind & Morris Goodman Cancer Institute, McGill University, Montreal, QCH3A 1A3, Canada
| | - Young K. Im
- Lady Davis Institute for Medical Research, Montreal, QCH3T 1E2, Canada
| | - Sai Kiran Naineni
- Department of Biochemistry, McGill University, Montreal, QC H3G 1Y6, Canada
- Rosalind & Morris Goodman Cancer Institute, McGill University, Montreal, QCH3A 1A3, Canada
| | - Mohamed Moustafa-Kamal
- Department of Biochemistry, McGill University, Montreal, QC H3G 1Y6, Canada
- Rosalind & Morris Goodman Cancer Institute, McGill University, Montreal, QCH3A 1A3, Canada
| | - Predrag Jovanovic
- Lady Davis Institute for Medical Research, Montreal, QCH3T 1E2, Canada
- Division of Experimental Medicine, McGill University, Montreal, QCH4A 3J1, Canada
| | - Valerie Sabourin
- Lady Davis Institute for Medical Research, Montreal, QCH3T 1E2, Canada
| | - Matthew G. Annis
- Rosalind & Morris Goodman Cancer Institute, McGill University, Montreal, QCH3A 1A3, Canada
| | - Francis Robert
- Department of Biochemistry, McGill University, Montreal, QC H3G 1Y6, Canada
- Rosalind & Morris Goodman Cancer Institute, McGill University, Montreal, QCH3A 1A3, Canada
| | - T. Martin Schmeing
- Department of Biochemistry, McGill University, Montreal, QC H3G 1Y6, Canada
- Rosalind & Morris Goodman Cancer Institute, McGill University, Montreal, QCH3A 1A3, Canada
| | - Antonis Koromilas
- Lady Davis Institute for Medical Research, Montreal, QCH3T 1E2, Canada
- Division of Experimental Medicine, McGill University, Montreal, QCH4A 3J1, Canada
- Gerald Bronfman Department of Oncology, McGill University, Montreal, QCH4A 3T2, Canada
| | - Marilène Paquet
- Département de pathologie et de microbiologie, Faculté de médecine vétérinaire, Université de Montréal, Montréal, QCH3C 3J7, Canada
| | - Jose G. Teodoro
- Department of Biochemistry, McGill University, Montreal, QC H3G 1Y6, Canada
- Rosalind & Morris Goodman Cancer Institute, McGill University, Montreal, QCH3A 1A3, Canada
| | - Sidong Huang
- Department of Biochemistry, McGill University, Montreal, QC H3G 1Y6, Canada
- Rosalind & Morris Goodman Cancer Institute, McGill University, Montreal, QCH3A 1A3, Canada
| | - Peter M. Siegel
- Department of Biochemistry, McGill University, Montreal, QC H3G 1Y6, Canada
- Rosalind & Morris Goodman Cancer Institute, McGill University, Montreal, QCH3A 1A3, Canada
- Division of Experimental Medicine, McGill University, Montreal, QCH4A 3J1, Canada
- Gerald Bronfman Department of Oncology, McGill University, Montreal, QCH4A 3T2, Canada
- Department of Medicine, McGill University, Montreal, QCH4A 3J1, Canada
| | - Ivan Topisirovic
- Department of Biochemistry, McGill University, Montreal, QC H3G 1Y6, Canada
- Lady Davis Institute for Medical Research, Montreal, QCH3T 1E2, Canada
- Division of Experimental Medicine, McGill University, Montreal, QCH4A 3J1, Canada
- Gerald Bronfman Department of Oncology, McGill University, Montreal, QCH4A 3T2, Canada
| | - Josie Ursini-Siegel
- Department of Biochemistry, McGill University, Montreal, QC H3G 1Y6, Canada
- Lady Davis Institute for Medical Research, Montreal, QCH3T 1E2, Canada
- Division of Experimental Medicine, McGill University, Montreal, QCH4A 3J1, Canada
- Gerald Bronfman Department of Oncology, McGill University, Montreal, QCH4A 3T2, Canada
| | - Jerry Pelletier
- Department of Biochemistry, McGill University, Montreal, QC H3G 1Y6, Canada
- Rosalind & Morris Goodman Cancer Institute, McGill University, Montreal, QCH3A 1A3, Canada
- Division of Experimental Medicine, McGill University, Montreal, QCH4A 3J1, Canada
- Gerald Bronfman Department of Oncology, McGill University, Montreal, QCH4A 3T2, Canada
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3
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Dong Y, Srour O, Lukhovitskaya N, Makarian J, Baumberger N, Galzitskaya O, Elser D, Schepetilnikov M, Ryabova LA. Functional analogs of mammalian 4E-BPs reveal a role for TOR in global plant translation. Cell Rep 2023; 42:112892. [PMID: 37516965 DOI: 10.1016/j.celrep.2023.112892] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 05/22/2023] [Accepted: 07/13/2023] [Indexed: 08/01/2023] Open
Abstract
Mammalian/mechanistic target of rapamycin (mTOR) regulates global protein synthesis through inactivation of eIF4E-binding proteins (m4E-BPs) in response to nutrient and energy availability. Until now, 4E-BPs have been considered as metazoan inventions, and how target of rapamycin (TOR) controls cap-dependent translation initiation in plants remains obscure. Here, we present short unstructured 4E-BP-like Arabidopsis proteins (4EBP1/4EBP2) that are non-homologous to m4E-BPs except for the eIF4E-binding motif and TOR phosphorylation sites. Unphosphorylated 4EBPs exhibit strong affinity toward eIF4Es and can inhibit formation of the cap-binding complex. Upon TOR activation, 4EBPs are phosphorylated, probably when bound directly to TOR, and likely relocated to ribosomes. 4EBPs can suppress a distinct set of mRNAs; 4EBP2 predominantly inhibits translation of core cell-cycle regulators CycB1;1 and CycD1;1, whereas 4EBP1 interferes with chlorophyll biosynthesis. Accordingly, 4EBP2 overexpression halts early seedling development, which is overcome by induction of Glc/Suc-TOR signaling. Thus, TOR regulates cap-dependent translation initiation by inactivating atypical 4EBPs in plants.
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Affiliation(s)
- Yihan Dong
- Institut de biologie moléculaire des plantes UPR2357 du CNRS, Université de Strasbourg, Strasbourg, France
| | - Ola Srour
- Institut de biologie moléculaire des plantes UPR2357 du CNRS, Université de Strasbourg, Strasbourg, France
| | - Nina Lukhovitskaya
- Institut de biologie moléculaire des plantes UPR2357 du CNRS, Université de Strasbourg, Strasbourg, France
| | - Joelle Makarian
- Institut de biologie moléculaire des plantes UPR2357 du CNRS, Université de Strasbourg, Strasbourg, France
| | - Nicolas Baumberger
- Institut de biologie moléculaire des plantes UPR2357 du CNRS, Université de Strasbourg, Strasbourg, France
| | - Oxana Galzitskaya
- Institute of Protein Research of the Russian Academy of Sciences, Pushchino, Moscow Region 142290, Russia
| | - David Elser
- Institut de biologie moléculaire des plantes UPR2357 du CNRS, Université de Strasbourg, Strasbourg, France
| | - Mikhail Schepetilnikov
- Institut de biologie moléculaire des plantes UPR2357 du CNRS, Université de Strasbourg, Strasbourg, France.
| | - Lyubov A Ryabova
- Institut de biologie moléculaire des plantes UPR2357 du CNRS, Université de Strasbourg, Strasbourg, France.
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4
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Cárdenas EL, O'Rourke RL, Menon A, Meagher J, Stuckey J, Garner AL. Design of Cell-Permeable Inhibitors of Eukaryotic Translation Initiation Factor 4E (eIF4E) for Inhibiting Aberrant Cap-Dependent Translation in Cancer. J Med Chem 2023; 66:10734-10745. [PMID: 37471629 DOI: 10.1021/acs.jmedchem.3c00917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/22/2023]
Abstract
Eukaryotic translation initiation factor 4E (eIF4E) is an RNA-binding protein that binds to the m7GpppX-cap at the 5' terminus of coding mRNAs to initiate cap-dependent translation. While all cells require cap-dependent translation, cancer cells become addicted to enhanced translational capacity, driving the production of oncogenic proteins involved in proliferation, evasion of apoptosis, metastasis, and angiogenesis, among other cancerous phenotypes. eIF4E is the rate-limiting translation factor, and its activation has been shown to drive cancer initiation, progression, metastasis, and drug resistance. These findings have established eIF4E as a translational oncogene and promising, albeit challenging, anti-cancer therapeutic target. Although significant effort has been put forth toward inhibiting eIF4E, the design of cell-permeable, cap-competitive inhibitors remains a challenge. Herein, we describe our work toward solving this long-standing challenge. By employing an acyclic nucleoside phosphonate prodrug strategy, we report the synthesis of cell-permeable inhibitors of eIF4E binding to capped mRNA to inhibit cap-dependent translation.
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Affiliation(s)
- Emilio L Cárdenas
- Department of Medicinal Chemistry, College of Pharmacy, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Rachel L O'Rourke
- Department of Medicinal Chemistry, College of Pharmacy, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Arya Menon
- Department of Medicinal Chemistry, College of Pharmacy, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Jennifer Meagher
- Life Science Institute, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Jeanne Stuckey
- Life Science Institute, University of Michigan, Ann Arbor, Michigan 48109, United States
- Rogel Cancer Center, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Amanda L Garner
- Department of Medicinal Chemistry, College of Pharmacy, University of Michigan, Ann Arbor, Michigan 48109, United States
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5
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Zhuang Y, Yang F, Menon A, Song JM, Espinoza RV, Schultz PJ, Garner AL, Tripathi A. An ECD and NMR/DP4+ Computational Pipeline for Structure Revision and Elucidation of Diphenazine-Based Natural Products. JOURNAL OF NATURAL PRODUCTS 2023; 86:1801-1814. [PMID: 37463274 DOI: 10.1021/acs.jnatprod.3c00306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/20/2023]
Abstract
Discovery and structure elucidation of natural products available in infinitesimally small quantities are recognized challenge. This challenge is epitomized by the diphenazine class of molecules that contain three bridged stereocenters, several conformations, ring fusions, and multiple spatially isolated phenols. Because empirical NMR and spatial analyses using ROESY/NOESY were unsuccessful in tackling these challenges, we developed a computational pipeline to determine the relative and absolute configurations and phenol positions of diphenazines as inhibitors of eukaryotic translation initiation factor 4E (eIF4E) protein-protein interactions. In this pipeline, we incorporated ECD and GIAO NMR calculations coupled with a DP4+ probability measure, enabling the structure revision of phenazinolin D (4), izumiphenazine A (5), and baraphenazine G (7) and the structure characterization of two new diphenazines, baraphenazine H (3) and izumiphenazine E (6). Importantly, through these efforts, we demonstrate the feasibility of NMR/DP4+ analysis for the determination of phenol positions in phenazine-based molecules, further expanding the limits of computational methods for the structure elucidation of complex natural products.
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Affiliation(s)
- Yihao Zhuang
- Department of Medicinal Chemistry, College of Pharmacy, University of Michigan, 1600 Huron Parkway, NCRC B520, Ann Arbor, Michigan 48109, United States
- Natural Product Discovery Core, Mary Sue Coleman Hall, University of Michigan, 210 Washtenaw Avenue, Ann Arbor, Michigan 48109, United States
| | - Fei Yang
- Natural Product Discovery Core, Mary Sue Coleman Hall, University of Michigan, 210 Washtenaw Avenue, Ann Arbor, Michigan 48109, United States
| | - Arya Menon
- Department of Medicinal Chemistry, College of Pharmacy, University of Michigan, 1600 Huron Parkway, NCRC B520, Ann Arbor, Michigan 48109, United States
| | - James M Song
- Program of Chemical Biology, Mary Sue Coleman Hall, University of Michigan, 210 Washtenaw Avenue, Ann Arbor, Michigan 48109, United States
| | - Rosa V Espinoza
- Natural Product Discovery Core, Mary Sue Coleman Hall, University of Michigan, 210 Washtenaw Avenue, Ann Arbor, Michigan 48109, United States
- Program of Chemical Biology, Mary Sue Coleman Hall, University of Michigan, 210 Washtenaw Avenue, Ann Arbor, Michigan 48109, United States
| | - Pamela J Schultz
- Natural Product Discovery Core, Mary Sue Coleman Hall, University of Michigan, 210 Washtenaw Avenue, Ann Arbor, Michigan 48109, United States
| | - Amanda L Garner
- Department of Medicinal Chemistry, College of Pharmacy, University of Michigan, 1600 Huron Parkway, NCRC B520, Ann Arbor, Michigan 48109, United States
| | - Ashootosh Tripathi
- Department of Medicinal Chemistry, College of Pharmacy, University of Michigan, 1600 Huron Parkway, NCRC B520, Ann Arbor, Michigan 48109, United States
- Natural Product Discovery Core, Mary Sue Coleman Hall, University of Michigan, 210 Washtenaw Avenue, Ann Arbor, Michigan 48109, United States
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6
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Nguyen TU, Hector H, Pederson EN, Lin J, Ouyang Z, Wendel HG, Singh K. Rapamycin-Induced Feedback Activation of eIF4E-EIF4A Dependent mRNA Translation in Pancreatic Cancer. Cancers (Basel) 2023; 15:1444. [PMID: 36900235 PMCID: PMC10001351 DOI: 10.3390/cancers15051444] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Accepted: 02/15/2023] [Indexed: 03/12/2023] Open
Abstract
Pancreatic cancer cells adapt molecular mechanisms to activate the protein synthesis to support tumor growth. This study reports the mTOR inhibitor rapamycin's specific and genome-wide effect on mRNA translation. Using ribosome footprinting in pancreatic cancer cells that lack the expression of 4EBP1, we establish the effect of mTOR-S6-dependent mRNAs translation. Rapamycin inhibits the translation of a subset of mRNAs including p70-S6K and proteins involved in the cell cycle and cancer cell growth. In addition, we identify translation programs that are activated following mTOR inhibition. Interestingly, rapamycin treatment results in the translational activation of kinases that are involved in mTOR signaling such as p90-RSK1. We further show that phospho-AKT1 and phospho-eIF4E are upregulated following mTOR inhibition suggesting a feedback activation of translation by rapamycin. Next, targeting eIF4E and eIF4A-dependent translation by using specific eIF4A inhibitors in combination with rapamycin shows significant growth inhibition in pancreatic cancer cells. In short, we establish the specific effect of mTOR-S6 on translation in cells lacking 4EBP1 and show that mTOR inhibition leads to feedback activation of translation via AKT-RSK1-eIF4E signals. Therefore, targeting translation downstream of mTOR presents a more efficient therapeutic strategy in pancreatic cancer.
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Affiliation(s)
- Trang Uyen Nguyen
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Albert Einstein Cancer Center, Bronx, NY 10461, USA
| | - Harrison Hector
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Albert Einstein Cancer Center, Bronx, NY 10461, USA
| | - Eric Nels Pederson
- Department of Biostatistics and Epidemiology, School of Public Health and Health Sciences, University of Massachusetts Amherst, Amherst, MA 01003, USA
| | - Jianan Lin
- Department of Biostatistics and Epidemiology, School of Public Health and Health Sciences, University of Massachusetts Amherst, Amherst, MA 01003, USA
| | - Zhengqing Ouyang
- Department of Biostatistics and Epidemiology, School of Public Health and Health Sciences, University of Massachusetts Amherst, Amherst, MA 01003, USA
| | - Hans-Guido Wendel
- Cancer Biology and Genetics, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Kamini Singh
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Albert Einstein Cancer Center, Bronx, NY 10461, USA
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7
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Shin S, Solorzano J, Liauzun M, Pyronnet S, Bousquet C, Martineau Y. Translational alterations in pancreatic cancer: a central role for the integrated stress response. NAR Cancer 2022; 4:zcac031. [PMID: 36325577 PMCID: PMC9615149 DOI: 10.1093/narcan/zcac031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Revised: 09/27/2022] [Accepted: 09/29/2022] [Indexed: 11/07/2022] Open
Abstract
mRNA translation is a key mechanism for cancer cell proliferation and stress adaptation. Regulation of this machinery implicates upstream pathways such as PI3K/AKT/mTOR, RAS/MEK/ERK and the integrated stress response (ISR), principally coordinating the translation initiation step. During the last decade, dysregulation of the mRNA translation process in pancreatic cancer has been widely reported, and shown to critically impact on cancer initiation, development and survival. This includes translation dysregulation of mRNAs encoding oncogenes and tumor suppressors. Hence, cancer cells survive a stressful microenvironment through a flexible regulation of translation initiation for rapid adaptation. The ISR pathway has an important role in chemoresistance and shows high potential therapeutic interest. Despite the numerous translational alterations reported in pancreatic cancer, their consequences are greatly underestimated. In this review, we summarize the different translation dysregulations described in pancreatic cancer, which make it invulnerable, as well as the latest drug discoveries bringing a glimmer of hope.
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Affiliation(s)
- Sauyeun Shin
- Centre de Recherche en Cancérologie de Toulouse (CRCT), INSERM U1037, Université Toulouse III Paul Sabatier, ERL5294 CNRS, Toulouse, France,Equipe labellisée Ligue Contre le Cancer
| | - Jacobo Solorzano
- Centre de Recherche en Cancérologie de Toulouse (CRCT), INSERM U1037, Université Toulouse III Paul Sabatier, ERL5294 CNRS, Toulouse, France,Equipe labellisée Ligue Contre le Cancer
| | - Mehdi Liauzun
- Centre de Recherche en Cancérologie de Toulouse (CRCT), INSERM U1037, Université Toulouse III Paul Sabatier, ERL5294 CNRS, Toulouse, France,Equipe labellisée Ligue Contre le Cancer
| | - Stéphane Pyronnet
- Centre de Recherche en Cancérologie de Toulouse (CRCT), INSERM U1037, Université Toulouse III Paul Sabatier, ERL5294 CNRS, Toulouse, France,Equipe labellisée Ligue Contre le Cancer
| | - Corinne Bousquet
- Centre de Recherche en Cancérologie de Toulouse (CRCT), INSERM U1037, Université Toulouse III Paul Sabatier, ERL5294 CNRS, Toulouse, France,Equipe labellisée Ligue Contre le Cancer
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8
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Xu ZH, Wang WQ, Liu L, Lou WH. A special subtype: Revealing the potential intervention and great value of KRAS wildtype pancreatic cancer. Biochim Biophys Acta Rev Cancer 2022; 1877:188751. [PMID: 35732240 DOI: 10.1016/j.bbcan.2022.188751] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 06/11/2022] [Accepted: 06/13/2022] [Indexed: 11/22/2022]
Abstract
Pancreatic ductal adenocarcinoma (PDAC) is the predominant form of pancreatic cancer and has devastating consequences on affected families and society. Its dismal prognosis is attributed to poor specificity of symptoms during early stages. It is widely believed that PDAC patients with the wildtype (WT) KRAS gene benefit more from currently available treatments than those with KRAS mutations. The oncogenic genetic changes alternations generally found in KRAS wildtype PDAC are related to either the KRAS pathway or microsatellite instability/mismatch repair deficiency (MSI/dMMR), which enable the application of tailored treatments based on each patient's genetic characteristics. This review focuses on targeted therapies against alternative tumour mechanisms in KRAS WT PDAC.
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Affiliation(s)
- Zhi-Hang Xu
- Department of Pancreatic Surgery, Zhongshan Hospital, Fudan University, Shanghai, China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Wen-Quan Wang
- Department of Pancreatic Surgery, Zhongshan Hospital, Fudan University, Shanghai, China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Liang Liu
- Department of Pancreatic Surgery, Zhongshan Hospital, Fudan University, Shanghai, China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China.
| | - Wen-Hui Lou
- Department of Pancreatic Surgery, Zhongshan Hospital, Fudan University, Shanghai, China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China.
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9
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Bortolin-Cavaillé ML, Quillien A, Thalalla Gamage S, Thomas J, Sas-Chen A, Sharma S, Plisson-Chastang C, Vandel L, Blader P, Lafontaine DLJ, Schwartz S, Meier J, Cavaillé J. Probing small ribosomal subunit RNA helix 45 acetylation across eukaryotic evolution. Nucleic Acids Res 2022; 50:6284-6299. [PMID: 35648437 PMCID: PMC9226516 DOI: 10.1093/nar/gkac404] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 04/28/2022] [Accepted: 05/31/2022] [Indexed: 01/06/2023] Open
Abstract
NAT10 is an essential enzyme that catalyzes N4-acetylcytidine (ac4C) in eukaryotic transfer RNA and 18S ribosomal RNA. Recent studies suggested that rRNA acetylation is dependent on SNORD13, a box C/D small nucleolar RNA predicted to base-pair with 18S rRNA via two antisense elements. However, the selectivity of SNORD13-dependent cytidine acetylation and its relationship to NAT10's essential function remain to be defined. Here, we demonstrate that SNORD13 is required for acetylation of a single cytidine of human and zebrafish 18S rRNA. In-depth characterization revealed that SNORD13-dependent ac4C is dispensable for human cell growth, ribosome biogenesis, translation and development. This loss of function analysis inspired a cross-evolutionary survey of the eukaryotic rRNA acetylation 'machinery' that led to the characterization of many novel metazoan SNORD13 genes. This includes an atypical SNORD13-like RNA in Drosophila melanogaster which guides ac4C to 18S rRNA helix 45 despite lacking one of the two rRNA antisense elements. Finally, we discover that Caenorhabditis elegans 18S rRNA is not acetylated despite the presence of an essential NAT10 homolog. Our findings shed light on the molecular mechanisms underlying SNORD13-mediated rRNA acetylation across eukaryotic evolution and raise new questions regarding the biological and evolutionary relevance of this highly conserved rRNA modification.
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Affiliation(s)
- Marie-Line Bortolin-Cavaillé
- Molecular, Cellular and Developmental Biology (MCD), UMR5077, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, F-31062 Toulouse, France
| | | | | | - Justin M Thomas
- Chemical Biology Laboratory, National Cancer Institute, Frederick, MD 21702, USA
| | - Aldema Sas-Chen
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Sunny Sharma
- RNA Molecular Biology, Fonds de la Recherche Scientifique (F.R.S./FNRS), Université libre de Bruxelles (ULB), Biopark campus, B-6041 Gosselies, Belgium
| | - Célia Plisson-Chastang
- Molecular, Cellular and Developmental Biology (MCD), UMR5077, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, F-31062 Toulouse, France
| | - Laurence Vandel
- Molecular, Cellular and Developmental Biology (MCD), UMR5077, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, F-31062 Toulouse, France
| | - Patrick Blader
- Molecular, Cellular and Developmental Biology (MCD), UMR5077, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, F-31062 Toulouse, France
| | - Denis L J Lafontaine
- RNA Molecular Biology, Fonds de la Recherche Scientifique (F.R.S./FNRS), Université libre de Bruxelles (ULB), Biopark campus, B-6041 Gosselies, Belgium
| | - Schraga Schwartz
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Jordan L Meier
- Chemical Biology Laboratory, National Cancer Institute, Frederick, MD 21702, USA
| | - Jérôme Cavaillé
- To whom correspondence should be addressed. Tel: +33 561335927; Fax: +33 561335886;
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10
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Alam M, Shima H, Matsuo Y, Long NC, Matsumoto M, Ishii Y, Sato N, Sugiyama T, Nobuta R, Hashimoto S, Liu L, Kaneko MK, Kato Y, Inada T, Igarashi K. mTORC1-independent translation control in mammalian cells by methionine adenosyltransferase 2A and S-adenosylmethionine. J Biol Chem 2022; 298:102084. [PMID: 35636512 PMCID: PMC9243181 DOI: 10.1016/j.jbc.2022.102084] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Revised: 05/19/2022] [Accepted: 05/20/2022] [Indexed: 11/21/2022] Open
Abstract
Methionine adenosyltransferase (MAT) catalyzes the synthesis of S-adenosylmethionine (SAM). As the sole methyl-donor for methylation of DNA, RNA, and proteins, SAM levels affect gene expression by changing methylation patterns. Expression of MAT2A, the catalytic subunit of isozyme MAT2, is positively correlated with proliferation of cancer cells; however, how MAT2A promotes cell proliferation is largely unknown. Given that the protein synthesis is induced in proliferating cells and that RNA and protein components of translation machinery are methylated, we tested here whether MAT2 and SAM are coupled with protein synthesis. By measuring ongoing protein translation via puromycin labeling, we revealed that MAT2A depletion or chemical inhibition reduced protein synthesis in HeLa and Hepa1 cells. Furthermore, overexpression of MAT2A enhanced protein synthesis, indicating that SAM is limiting under normal culture conditions. In addition, MAT2 inhibition did not accompany reduction in mechanistic target of rapamycin complex 1 activity but nevertheless reduced polysome formation. Polysome-bound RNA sequencing revealed that MAT2 inhibition decreased translation efficiency of some fraction of mRNAs. MAT2A was also found to interact with the proteins involved in rRNA processing and ribosome biogenesis; depletion or inhibition of MAT2 reduced 18S rRNA processing. Finally, quantitative mass spectrometry revealed that some translation factors were dynamically methylated in response to the activity of MAT2A. These observations suggest that cells possess an mTOR-independent regulatory mechanism that tunes translation in response to the levels of SAM. Such a system may acclimate cells for survival when SAM synthesis is reduced, whereas it may support proliferation when SAM is sufficient.
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Affiliation(s)
- Mahabub Alam
- Department of Biochemistry, Tohoku University Graduate School of Medicine, Sendai, Japan; Department of Animal Science and Nutrition, Faculty of Veterinary Medicine, Chattogram Veterinary and Animal Sciences University, Chattogram, Bangladesh
| | - Hiroki Shima
- Department of Biochemistry, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Yoshitaka Matsuo
- Division of RNA and Gene Regulation, Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - Nguyen Chi Long
- Department of Biochemistry, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Mitsuyo Matsumoto
- Department of Biochemistry, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Yusho Ishii
- Department of Biochemistry, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Nichika Sato
- Division of RNA and Gene Regulation, Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - Takato Sugiyama
- Laboratory of Gene Regulation, Department of Molecular Biopharmacy and Genetics, Tohoku University Graduate School of Pharmaceutical Science, Sendai, Japan
| | - Risa Nobuta
- Laboratory of Gene Regulation, Department of Molecular Biopharmacy and Genetics, Tohoku University Graduate School of Pharmaceutical Science, Sendai, Japan
| | - Satoshi Hashimoto
- Laboratory of Gene Regulation, Department of Molecular Biopharmacy and Genetics, Tohoku University Graduate School of Pharmaceutical Science, Sendai, Japan
| | - Liang Liu
- Department of Biochemistry, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Mika K Kaneko
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Yukinari Kato
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan; Department of Molecular Pharmacology, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Toshifumi Inada
- Division of RNA and Gene Regulation, Institute of Medical Science, The University of Tokyo, Tokyo, Japan.
| | - Kazuhiko Igarashi
- Department of Biochemistry, Tohoku University Graduate School of Medicine, Sendai, Japan.
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11
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Herzog LO, Walters B, Buono R, Lee JS, Mallya S, Fung A, Chiu H, Nguyen N, Li B, Pinkerton AB, Jackson MR, Schneider RJ, Ronai ZA, Fruman DA. Targeting eIF4F translation initiation complex with SBI-756 sensitises B lymphoma cells to venetoclax. Br J Cancer 2021; 124:1098-1109. [PMID: 33318657 PMCID: PMC7960756 DOI: 10.1038/s41416-020-01205-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 09/30/2020] [Accepted: 11/20/2020] [Indexed: 01/29/2023] Open
Abstract
BACKGROUND The BCL2 inhibitor venetoclax has shown efficacy in several hematologic malignancies, with the greatest response rates in indolent blood cancers such as chronic lymphocytic leukaemia. There is a lower response rate to venetoclax monotherapy in diffuse large B-cell lymphoma (DLBCL). METHODS We tested inhibitors of cap-dependent mRNA translation for the ability to sensitise DLBCL and mantle cell lymphoma (MCL) cells to apoptosis by venetoclax. We compared the mTOR kinase inhibitor (TOR-KI) MLN0128 with SBI-756, a compound targeting eukaryotic translation initiation factor 4G1 (eIF4G1), a scaffolding protein in the eIF4F complex. RESULTS Treatment of DLBCL and MCL cells with SBI-756 synergised with venetoclax to induce apoptosis in vitro, and enhanced venetoclax efficacy in vivo. SBI-756 prevented eIF4E-eIF4G1 association and cap-dependent translation without affecting mTOR substrate phosphorylation. In TOR-KI-resistant DLBCL cells lacking eIF4E binding protein-1, SBI-756 still sensitised to venetoclax. SBI-756 selectively reduced translation of mRNAs encoding ribosomal proteins and translation factors, leading to a reduction in protein synthesis rates in sensitive cells. When normal lymphocytes were treated with SBI-756, only B cells had reduced viability, and this correlated with reduced protein synthesis. CONCLUSIONS Our data highlight a novel combination for treatment of aggressive lymphomas, and establishes its efficacy and selectivity using preclinical models.
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Affiliation(s)
- Lee-or Herzog
- grid.266093.80000 0001 0668 7243Department of Molecular Biology & Biochemistry, University of California, Irvine, CA 92697 USA
| | - Beth Walters
- grid.137628.90000 0004 1936 8753New York University School of Medicine, New York, NY USA
| | - Roberta Buono
- grid.266093.80000 0001 0668 7243Department of Molecular Biology & Biochemistry, University of California, Irvine, CA 92697 USA
| | - J. Scott Lee
- grid.266093.80000 0001 0668 7243Department of Molecular Biology & Biochemistry, University of California, Irvine, CA 92697 USA ,grid.418185.10000 0004 0627 6737Genomics Institute of the Novartis Research Foundation, San Diego, CA 92121 USA
| | - Sharmila Mallya
- grid.266093.80000 0001 0668 7243Department of Molecular Biology & Biochemistry, University of California, Irvine, CA 92697 USA
| | - Amos Fung
- grid.266093.80000 0001 0668 7243Department of Molecular Biology & Biochemistry, University of California, Irvine, CA 92697 USA
| | - Honyin Chiu
- grid.266093.80000 0001 0668 7243Department of Molecular Biology & Biochemistry, University of California, Irvine, CA 92697 USA ,grid.416879.50000 0001 2219 0587Benaroya Research Institute, Seattle, WA 98101 USA
| | - Nancy Nguyen
- grid.266093.80000 0001 0668 7243Department of Molecular Biology & Biochemistry, University of California, Irvine, CA 92697 USA
| | - Boyang Li
- grid.266093.80000 0001 0668 7243Department of Molecular Biology & Biochemistry, University of California, Irvine, CA 92697 USA
| | - Anthony B. Pinkerton
- grid.479509.60000 0001 0163 8573Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037 USA
| | - Michael R. Jackson
- grid.479509.60000 0001 0163 8573Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037 USA
| | - Robert J. Schneider
- grid.137628.90000 0004 1936 8753New York University School of Medicine, New York, NY USA
| | - Ze’ev A. Ronai
- grid.479509.60000 0001 0163 8573Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037 USA
| | - David A. Fruman
- grid.266093.80000 0001 0668 7243Department of Molecular Biology & Biochemistry, University of California, Irvine, CA 92697 USA
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12
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Driver mutations of the adenoma-carcinoma sequence govern the intestinal epithelial global translational capacity. Proc Natl Acad Sci U S A 2020; 117:25560-25570. [PMID: 32989144 DOI: 10.1073/pnas.1912772117] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Deregulated global mRNA translation is an emerging feature of cancer cells. Oncogenic transformation in colorectal cancer (CRC) is driven by mutations in APC, KRAS, SMAD4, and TP53, known as the adenoma-carcinoma sequence (ACS). Here we introduce each of these driver mutations into intestinal organoids to show that they are modulators of global translational capacity in intestinal epithelial cells. Increased global translation resulting from loss of Apc expression was potentiated by the presence of oncogenic Kras G12D Knockdown of Smad4 further enhanced global translation efficiency and was associated with a lower 4E-BP1-to-eIF4E ratio. Quadruple mutant cells with additional P53 loss displayed the highest global translational capacity, paralleled by high proliferation and growth rates, indicating that the proteome is heavily geared toward cell division. Transcriptional reprogramming facilitating global translation included elevated ribogenesis and activation of mTORC1 signaling. Accordingly, interfering with the mTORC1/4E-BP/eIF4E axis inhibited the growth potential endowed by accumulation of multiple drivers. In conclusion, the ACS is characterized by a strongly altered global translational landscape in epithelial cells, exposing a therapeutic potential for direct targeting of the translational apparatus.
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13
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Batool A, Majeed ST, Aashaq S, Majeed R, Andrabi KI. Eukaryotic Initiation Factor 4E phosphorylation acts a switch for its binding to 4E-BP1 and mRNA cap assembly. Biochem Biophys Res Commun 2020; 527:489-495. [PMID: 32336547 DOI: 10.1016/j.bbrc.2020.04.086] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2020] [Accepted: 04/16/2020] [Indexed: 11/28/2022]
Abstract
Translational regulation has invited considerable interest consequent of its circumstantial dysregulation during cancer genesis. eIF4E (Eukaryotic Initiation Factor 4E) has been identified as an important factor involved in tumor progression by way of instrumenting the convergence of oncogenic signals for up-regulation of Cap-dependent translation. In the backdrop of dramatic eIF4E over-expression in a large population of human cancers, we suggest that the tumorigenic property of eIF4E is strictly attributed to its phosphorylation state. We provide evidence that while phosphorylated eIF4E fails to be sequestered by 4E-BP1, its dephosphorylated form shows overwhelming binding with 4E-BP1 without any consideration to the state of 4E-BP1 phosphorylation to suggest that eIF4E-4EBP1 binding is governed by eIF4E phosphorylation instead of 4E-BP1. We also show that eIF4E engages in Cap-assembly formation preferably in a phosphorylation-dependent manner to suggest that eIF4E phosphorylation rather than 4E-BP1 regulates its availability for Cap-assembly.
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Affiliation(s)
- Asiya Batool
- Department of Biotechnology, Science Block, University of Kashmir, Srinagar, 190006, J&K, India
| | - Sheikh Tahir Majeed
- Department of Biotechnology, Science Block, University of Kashmir, Srinagar, 190006, J&K, India
| | - Sabreena Aashaq
- Department of Biotechnology, Science Block, University of Kashmir, Srinagar, 190006, J&K, India
| | - Rabiya Majeed
- Department of Biotechnology, Science Block, University of Kashmir, Srinagar, 190006, J&K, India
| | - Khurshid Iqbal Andrabi
- Department of Biotechnology, Science Block, University of Kashmir, Srinagar, 190006, J&K, India.
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14
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Xu Y, Ruggero D. The Role of Translation Control in Tumorigenesis and Its Therapeutic Implications. ANNUAL REVIEW OF CANCER BIOLOGY-SERIES 2020. [DOI: 10.1146/annurev-cancerbio-030419-033420] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
As a convergent mechanism downstream of most oncogenic signals, control of mRNA translation has emerged as a key driver in establishing and tuning gene expression at specific steps in cancer development. Translation control is the most energetically expensive molecular process in the cell that needs to be modulated upon adaption to limited cellular resources, such as cellular stress. It thereby serves as the Achilles’ heel for cancer cells, particularly in response to changes in the microenvironment as well as to nutrient and metabolic shifts characteristic of cancer cell growth and metastasis. In this review, we discuss emerging discoveries that reveal how cancer cells modulate the translation machinery to adapt to oncogenic stress, the mechanisms that guide mRNA translation specificity in cancer, and how this selective mode of gene regulation provides advantages for cancer progression. We also provide an overview of promising preclinical and clinical efforts aimed at targeting the unique vulnerabilities of cancer cells that rely on the remodeling of mRNA translation for their infinite growth and survival.
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Affiliation(s)
- Yichen Xu
- Department of Urology and Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, California 94157, USA
| | - Davide Ruggero
- Department of Urology and Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, California 94157, USA
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, California 94158, USA
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15
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Chen R, Malagola E, Dietrich M, Zuellig R, Tschopp O, Bombardo M, Saponara E, Reding T, Myers S, Hills AP, Graf R, Sonda S. Akt1 signalling supports acinar proliferation and limits acinar-to-ductal metaplasia formation upon induction of acute pancreatitis. J Pathol 2019; 250:42-54. [PMID: 31531867 DOI: 10.1002/path.5348] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Revised: 09/04/2019] [Accepted: 09/12/2019] [Indexed: 12/30/2022]
Abstract
Molecular signalling mediated by the phosphatidylinositol-3-kinase (PI3K)-Akt axis is a key regulator of cellular functions. Importantly, alteration of the PI3K-Akt signalling underlies the development of different human diseases, thus prompting the investigation of the pathway as a molecular target for pharmacologic intervention. In this regard, recent studies showed that small molecule inhibitors of PI3K, the upstream regulator of the pathway, reduced the development of inflammation during acute pancreatitis, a highly debilitating and potentially lethal disease. Here we investigated whether a specific reduction of Akt activity, by using either pharmacologic Akt inhibition, or genetic inactivation of the Akt1 isoform selectively in pancreatic acinar cells, is effective in ameliorating the onset and progression of the disease. We discovered that systemic reduction of Akt activity did not protect the pancreas from initial damage and only transiently delayed leukocyte recruitment. However, reduction of Akt activity decreased acinar proliferation and exacerbated acinar-to-ductal metaplasia (ADM) formation, two critical events in the progression of pancreatitis. These phenotypes were recapitulated upon conditional inactivation of Akt1 in acinar cells, which resulted in reduced expression of 4E-BP1, a multifunctional protein of key importance in cell proliferation and metaplasia formation. Collectively, our results highlight the critical role played by Akt1 during the development of acute pancreatitis in the control of acinar cell proliferation and ADM formation. In addition, these results harbour important translational implications as they raise the concern that inhibitors of PI3K-Akt signalling pathways may negatively affect the regeneration of the pancreas. Finally, this work provides the basis for further investigating the potential of Akt1 activators to boost pancreatic regeneration following inflammatory insults. © 2019 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
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Affiliation(s)
- Rong Chen
- Swiss Hepato-Pancreato-Biliary Center, Department of Visceral and Transplantation Surgery, University Hospital, Zurich, Switzerland
| | - Ermanno Malagola
- Swiss Hepato-Pancreato-Biliary Center, Department of Visceral and Transplantation Surgery, University Hospital, Zurich, Switzerland
| | - Maren Dietrich
- Division of Endocrinology, Diabetes and Clinical Nutrition, University Hospital, Zurich, Switzerland
| | - Richard Zuellig
- Division of Endocrinology, Diabetes and Clinical Nutrition, University Hospital, Zurich, Switzerland
| | - Oliver Tschopp
- Division of Endocrinology, Diabetes and Clinical Nutrition, University Hospital, Zurich, Switzerland
| | - Marta Bombardo
- Swiss Hepato-Pancreato-Biliary Center, Department of Visceral and Transplantation Surgery, University Hospital, Zurich, Switzerland
| | - Enrica Saponara
- Swiss Hepato-Pancreato-Biliary Center, Department of Visceral and Transplantation Surgery, University Hospital, Zurich, Switzerland
| | - Theresia Reding
- Swiss Hepato-Pancreato-Biliary Center, Department of Visceral and Transplantation Surgery, University Hospital, Zurich, Switzerland
| | - Stephen Myers
- School of Health Sciences, College of Health and Medicine, University of Tasmania, Launceston, Tasmania, Australia
| | - Andrew P Hills
- School of Health Sciences, College of Health and Medicine, University of Tasmania, Launceston, Tasmania, Australia
| | - Rolf Graf
- Swiss Hepato-Pancreato-Biliary Center, Department of Visceral and Transplantation Surgery, University Hospital, Zurich, Switzerland.,Center for Integrative Human Physiology (ZIHP), University of Zurich, Zurich, Switzerland
| | - Sabrina Sonda
- Swiss Hepato-Pancreato-Biliary Center, Department of Visceral and Transplantation Surgery, University Hospital, Zurich, Switzerland.,School of Health Sciences, College of Health and Medicine, University of Tasmania, Launceston, Tasmania, Australia.,Center for Integrative Human Physiology (ZIHP), University of Zurich, Zurich, Switzerland
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16
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Müller D, Shin S, Goullet de Rugy T, Samain R, Baer R, Strehaiano M, Masvidal-Sanz L, Guillermet-Guibert J, Jean C, Tsukumo Y, Sonenberg N, Marion F, Guilbaud N, Hoffmann JS, Larsson O, Bousquet C, Pyronnet S, Martineau Y. eIF4A inhibition circumvents uncontrolled DNA replication mediated by 4E-BP1 loss in pancreatic cancer. JCI Insight 2019; 4:121951. [PMID: 31672935 DOI: 10.1172/jci.insight.121951] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2018] [Accepted: 09/20/2019] [Indexed: 01/08/2023] Open
Abstract
Pancreatic ductal adenocarcinoma (PDAC) relies on hyperactivated protein synthesis. Consistently, human and mouse PDAC lose expression of the translational repressor and mTOR target 4E-BP1. Using genome-wide polysome profiling, we here explore mRNAs whose translational efficiencies depend on the mTOR/4E-BP1 axis in pancreatic cancer cells. We identified a functional enrichment for mRNAs encoding DNA replication and repair proteins, including RRM2 and CDC6. Consequently, 4E-BP1 depletion favors DNA repair and renders DNA replication insensitive to mTOR inhibitors, in correlation with a sustained protein expression of CDC6 and RRM2, which is inversely correlated with 4E-BP1 expression in PDAC patient samples. DNA damage and pancreatic lesions induced by an experimental pancreatitis model uncover that 4E-BP1/2-deleted mice display an increased acinar cell proliferation and a better recovery than WT animals. Targeting translation, independently of 4E-BP1 status, using eIF4A RNA helicase inhibitors (silvestrol derivatives) selectively modulates translation and limits CDC6 expression and DNA replication, leading to reduced PDAC tumor growth. In summary, 4E-BP1 expression loss during PDAC development induces selective changes in translation of mRNA encoding DNA replication and repair protein. Importantly, targeting protein synthesis by eIF4A inhibitors circumvents PDAC resistance to mTOR inhibition.
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Affiliation(s)
- David Müller
- Cancer Research Center of Toulouse (CRCT), INSERM UMR 1037, University Toulouse III Paul Sabatier, ERL5294 CNRS, Toulouse, France.,Equipe Labellisée Ligue Contre le Cancer and Laboratoire d'Excellence Toulouse Cancer (TOUCAN), Toulouse, France
| | - Sauyeun Shin
- Cancer Research Center of Toulouse (CRCT), INSERM UMR 1037, University Toulouse III Paul Sabatier, ERL5294 CNRS, Toulouse, France.,Equipe Labellisée Ligue Contre le Cancer and Laboratoire d'Excellence Toulouse Cancer (TOUCAN), Toulouse, France
| | - Théo Goullet de Rugy
- Cancer Research Center of Toulouse (CRCT), INSERM UMR 1037, University Toulouse III Paul Sabatier, ERL5294 CNRS, Toulouse, France
| | - Rémi Samain
- Cancer Research Center of Toulouse (CRCT), INSERM UMR 1037, University Toulouse III Paul Sabatier, ERL5294 CNRS, Toulouse, France.,Equipe Labellisée Ligue Contre le Cancer and Laboratoire d'Excellence Toulouse Cancer (TOUCAN), Toulouse, France
| | - Romain Baer
- Cancer Research Center of Toulouse (CRCT), INSERM UMR 1037, University Toulouse III Paul Sabatier, ERL5294 CNRS, Toulouse, France
| | - Manon Strehaiano
- Cancer Research Center of Toulouse (CRCT), INSERM UMR 1037, University Toulouse III Paul Sabatier, ERL5294 CNRS, Toulouse, France.,Equipe Labellisée Ligue Contre le Cancer and Laboratoire d'Excellence Toulouse Cancer (TOUCAN), Toulouse, France
| | - Laia Masvidal-Sanz
- Department of Oncology-Pathology, Science for Life Laboratory, Karolinska Institutet, Solna, Sweden
| | - Julie Guillermet-Guibert
- Cancer Research Center of Toulouse (CRCT), INSERM UMR 1037, University Toulouse III Paul Sabatier, ERL5294 CNRS, Toulouse, France
| | - Christine Jean
- Cancer Research Center of Toulouse (CRCT), INSERM UMR 1037, University Toulouse III Paul Sabatier, ERL5294 CNRS, Toulouse, France.,Equipe Labellisée Ligue Contre le Cancer and Laboratoire d'Excellence Toulouse Cancer (TOUCAN), Toulouse, France
| | - Yoshinori Tsukumo
- Molecular Diagnostics Section, Division of Molecular Target and Gene Therapy Products, National Institute of Health Sciences, Tokyo, Japan
| | - Nahum Sonenberg
- Department of Biochemistry and Goodman Cancer Research Centre, McGill University, Montreal, Quebec, Canada
| | - Frédéric Marion
- Research and Development Center, Laboratoires Pierre Fabre, Toulouse, France
| | - Nicolas Guilbaud
- Research and Development Center, Laboratoires Pierre Fabre, Toulouse, France
| | - Jean-Sébastien Hoffmann
- Cancer Research Center of Toulouse (CRCT), INSERM UMR 1037, University Toulouse III Paul Sabatier, ERL5294 CNRS, Toulouse, France
| | - Ola Larsson
- Department of Oncology-Pathology, Science for Life Laboratory, Karolinska Institutet, Solna, Sweden
| | - Corinne Bousquet
- Cancer Research Center of Toulouse (CRCT), INSERM UMR 1037, University Toulouse III Paul Sabatier, ERL5294 CNRS, Toulouse, France.,Equipe Labellisée Ligue Contre le Cancer and Laboratoire d'Excellence Toulouse Cancer (TOUCAN), Toulouse, France
| | - Stéphane Pyronnet
- Cancer Research Center of Toulouse (CRCT), INSERM UMR 1037, University Toulouse III Paul Sabatier, ERL5294 CNRS, Toulouse, France.,Equipe Labellisée Ligue Contre le Cancer and Laboratoire d'Excellence Toulouse Cancer (TOUCAN), Toulouse, France
| | - Yvan Martineau
- Cancer Research Center of Toulouse (CRCT), INSERM UMR 1037, University Toulouse III Paul Sabatier, ERL5294 CNRS, Toulouse, France.,Equipe Labellisée Ligue Contre le Cancer and Laboratoire d'Excellence Toulouse Cancer (TOUCAN), Toulouse, France
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17
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Park SJ, Kim H, Kim SH, Joe EH, Jou I. Epigenetic downregulation of STAT6 increases HIF-1α expression via mTOR/S6K/S6, leading to enhanced hypoxic viability of glioma cells. Acta Neuropathol Commun 2019; 7:149. [PMID: 31530290 PMCID: PMC6747735 DOI: 10.1186/s40478-019-0798-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2019] [Accepted: 08/26/2019] [Indexed: 01/01/2023] Open
Abstract
Multifunctional signal transducer and activator of transcription (STAT) proteins play important roles in cancer. Here, we have shown that STAT6 is epigenetically silenced in some cases of malignant glioblastoma, which facilitates cancer cell survival in a hypoxic microenvironment. This downregulation results from hypermethylation of CpG islands within the STAT6 promoter by DNA methyltransferases. STAT6 interacts with Rheb under hypoxia and inhibits mTOR/S6K/S6 signaling, in turn, inducing increased HIF-1α translation. STAT6 silencing and consequent tumor-promoting effects are additionally observed in glioma stem-like cells (GSC). Despite recent advances in cancer treatment, survival rates have shown little improvement. This is particularly true in the case of glioma, where multimodal treatment and precision medicine is needed. Our study supports the application of epigenetic restoration of STAT6 with the aid of DNA methyltransferase inhibitors, such as 5-aza-2-deoxycytidine, for treatment of STAT6-silenced gliomas.
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18
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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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19
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Robichaud N, Sonenberg N, Ruggero D, Schneider RJ. Translational Control in Cancer. Cold Spring Harb Perspect Biol 2019; 11:cshperspect.a032896. [PMID: 29959193 DOI: 10.1101/cshperspect.a032896] [Citation(s) in RCA: 159] [Impact Index Per Article: 31.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The translation of messenger RNAs (mRNAs) into proteins is a key event in the regulation of gene expression. This is especially true in the cancer setting, as many oncogenes and transforming events are regulated at this level. Cancer-promoting factors that are translationally regulated include cyclins, antiapoptotic factors, proangiogenic factors, regulators of cell metabolism, prometastatic factors, immune modulators, and proteins involved in DNA repair. This review discusses the diverse means by which cancer cells deregulate and reprogram translation, and the resulting oncogenic impacts, providing insights into the complexity of translational control in cancer and its targeting for cancer therapy.
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Affiliation(s)
- Nathaniel Robichaud
- Goodman Cancer Research Centre and Department of Biochemistry, McGill University, Montreal, Quebec H3A 1A3, Canada
| | - Nahum Sonenberg
- Goodman Cancer Research Centre and Department of Biochemistry, McGill University, Montreal, Quebec H3A 1A3, Canada
| | - Davide Ruggero
- Helen Diller Family Comprehensive Cancer Center, and Departments of Urology and of Cellular and Molecular Pharmacology, University of California, San Francisco, California 94158
| | - Robert J Schneider
- NYU School of Medicine, Alexandria Center for Life Science, New York, New York 10016
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20
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Frosi Y, Usher R, Lian DTG, Lane DP, Brown CJ. Monitoring flux in signalling pathways through measurements of 4EBP1-mediated eIF4F complex assembly. BMC Biol 2019; 17:40. [PMID: 31118010 PMCID: PMC6530213 DOI: 10.1186/s12915-019-0658-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Accepted: 04/29/2019] [Indexed: 01/10/2023] Open
Abstract
Background The most commonly occurring cancer mutations, including oncogenes such as MYC, Ras and PIK3C, are found in signal transductions pathways feeding into the translational machinery. A broad range of translation initiation factors are also commonly found to be either amplified or mis-regulated in tumours, including eIF4E (elongation initiation factor 4E). eIF4E is a subunit of the eIF4F protein initiation complex and required for its recruitment. Here we measure the formation of the eIF4F complex through interactions of eIF4E and eIF4G subunits, and the effect of oncogenic signalling pathways on complex formation. Results We developed a protein fragment complementation (PCA) assay that can accurately measure the status of the eIF4E-eIF4G interaction in cells and quantify the signalling flux through the RAS/ERK and PI3K/AKT pathways regulating eIF4F assembly. Complex disruption induced by inhibition of either pathway was shown to be a function of the phosphorylation status of 4EBP1, a key mediator of eIF4F assembly that interacts directly with eIF4E, confirming 4EBP1’s ability to integrate multiple signals affecting cap-dependent translation. Maximal measured disruption of the eIF4F complex occurred under combined mTORC1 and mTORC2 inhibition, whilst combined inhibition of both RAS/ERK and PI3K/AKT pathways in parallel resulted in greater inhibition of eIF4F formation than individually. v-Myc-mediated resistance to dual mTORC/PI3K inhibition was also principally demonstrated to depend on the lack of competent 4EBP1 available in the cell to bind eIF4E. Conclusions We show that 4EBP1 is a critical regulator of the mitogen responsive RAS/ERK and PI3K/AKT pathways and a key transducer of resistance mechanisms that affect small molecule inhibition of these pathways, principally by attenuating their effects on cap-dependent translation. These findings highlight the importance of highly efficacious direct inhibitors of eIF4E and eIF4F assembly, which could potentially target a wide spectrum of tumours containing differing mutations that effect these pathways and which confer chemo-resistance. Electronic supplementary material The online version of this article (10.1186/s12915-019-0658-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Yuri Frosi
- p53 Laboratory, A*STAR (Agency for Science, Technology and Research), 8A Biomedical Grove, #06-04/05, Neuros/Immunos, Singapore, 138648, Singapore
| | - Rachael Usher
- p53 Laboratory, A*STAR (Agency for Science, Technology and Research), 8A Biomedical Grove, #06-04/05, Neuros/Immunos, Singapore, 138648, Singapore
| | - Dawn Thean Gek Lian
- p53 Laboratory, A*STAR (Agency for Science, Technology and Research), 8A Biomedical Grove, #06-04/05, Neuros/Immunos, Singapore, 138648, Singapore
| | - David P Lane
- p53 Laboratory, A*STAR (Agency for Science, Technology and Research), 8A Biomedical Grove, #06-04/05, Neuros/Immunos, Singapore, 138648, Singapore
| | - Christopher J Brown
- p53 Laboratory, A*STAR (Agency for Science, Technology and Research), 8A Biomedical Grove, #06-04/05, Neuros/Immunos, Singapore, 138648, Singapore.
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21
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Targeting mTOR in Acute Lymphoblastic Leukemia. Cells 2019; 8:cells8020190. [PMID: 30795552 PMCID: PMC6406494 DOI: 10.3390/cells8020190] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Revised: 02/12/2019] [Accepted: 02/16/2019] [Indexed: 12/12/2022] Open
Abstract
Acute Lymphoblastic Leukemia (ALL) is an aggressive hematologic disorder and constitutes approximately 25% of cancer diagnoses among children and teenagers. Pediatric patients have a favourable prognosis, with 5-years overall survival rates near 90%, while adult ALL still correlates with poorer survival. However, during the past few decades, the therapeutic outcome of adult ALL was significantly ameliorated, mainly due to intensive pediatric-based protocols of chemotherapy. Mammalian (or mechanistic) target of rapamycin (mTOR) is a conserved serine/threonine kinase belonging to the phosphatidylinositol 3-kinase (PI3K)-related kinase family (PIKK) and resides in two distinct signalling complexes named mTORC1, involved in mRNA translation and protein synthesis and mTORC2 that controls cell survival and migration. Moreover, both complexes are remarkably involved in metabolism regulation. Growing evidence reports that mTOR dysregulation is related to metastatic potential, cell proliferation and angiogenesis and given that PI3K/Akt/mTOR network activation is often associated with poor prognosis and chemoresistance in ALL, there is a constant need to discover novel inhibitors for ALL treatment. Here, the current knowledge of mTOR signalling and the development of anti-mTOR compounds are documented, reporting the most relevant results from both preclinical and clinical studies in ALL that have contributed significantly into their efficacy or failure.
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22
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Liu S, Hausmann S, Carlson SM, Fuentes ME, Francis JW, Pillai R, Lofgren SM, Hulea L, Tandoc K, Lu J, Li A, Nguyen ND, Caporicci M, Kim MP, Maitra A, Wang H, Wistuba II, Porco JA, Bassik MC, Elias JE, Song J, Topisirovic I, Van Rechem C, Mazur PK, Gozani O. METTL13 Methylation of eEF1A Increases Translational Output to Promote Tumorigenesis. Cell 2019; 176:491-504.e21. [PMID: 30612740 PMCID: PMC6499081 DOI: 10.1016/j.cell.2018.11.038] [Citation(s) in RCA: 111] [Impact Index Per Article: 22.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2018] [Revised: 10/18/2018] [Accepted: 11/21/2018] [Indexed: 12/25/2022]
Abstract
Increased protein synthesis plays an etiologic role in diverse cancers. Here, we demonstrate that METTL13 (methyltransferase-like 13) dimethylation of eEF1A (eukaryotic elongation factor 1A) lysine 55 (eEF1AK55me2) is utilized by Ras-driven cancers to increase translational output and promote tumorigenesis in vivo. METTL13-catalyzed eEF1A methylation increases eEF1A's intrinsic GTPase activity in vitro and protein production in cells. METTL13 and eEF1AK55me2 levels are upregulated in cancer and negatively correlate with pancreatic and lung cancer patient survival. METTL13 deletion and eEF1AK55me2 loss dramatically reduce Ras-driven neoplastic growth in mouse models and in patient-derived xenografts (PDXs) from primary pancreatic and lung tumors. Finally, METTL13 depletion renders PDX tumors hypersensitive to drugs that target growth-signaling pathways. Together, our work uncovers a mechanism by which lethal cancers become dependent on the METTL13-eEF1AK55me2 axis to meet their elevated protein synthesis requirement and suggests that METTL13 inhibition may constitute a targetable vulnerability of tumors driven by aberrant Ras signaling.
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Affiliation(s)
- Shuo Liu
- Department of Biology, Stanford University, Stanford, CA 94305, USA
| | - Simone Hausmann
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | | | - Mary Esmeralda Fuentes
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | | | - Renjitha Pillai
- Department of Pathology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Shane Michael Lofgren
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Laura Hulea
- Lady Davis Institute and Gerald Bronfman Department of Oncology, McGill University, Montreal, QC H3T 1E2, Canada
| | - Kristofferson Tandoc
- Lady Davis Institute and Gerald Bronfman Department of Oncology, McGill University, Montreal, QC H3T 1E2, Canada
| | - Jiuwei Lu
- Department of Biochemistry, University of California, Riverside, Riverside, CA 92521, USA
| | - Ami Li
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Nicholas Dang Nguyen
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Marcello Caporicci
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Michael Paul Kim
- Department of Surgical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Anirban Maitra
- Department of Translational Molecular Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Huamin Wang
- Department of Translational Molecular Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA; Department of Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Ignacio Ivan Wistuba
- Department of Translational Molecular Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA; Department of Thoracic/Head and Neck Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | | | - Michael Cory Bassik
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Joshua Eric Elias
- Deparment of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Jikui Song
- Department of Biochemistry, University of California, Riverside, Riverside, CA 92521, USA
| | - Ivan Topisirovic
- Lady Davis Institute and Gerald Bronfman Department of Oncology, McGill University, Montreal, QC H3T 1E2, Canada
| | - Capucine Van Rechem
- Department of Pathology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Pawel Karol Mazur
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
| | - Or Gozani
- Department of Biology, Stanford University, Stanford, CA 94305, USA.
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23
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Jastrzebski K, Thijssen B, Kluin RJC, de Lint K, Majewski IJ, Beijersbergen RL, Wessels LFA. Integrative Modeling Identifies Key Determinants of Inhibitor Sensitivity in Breast Cancer Cell Lines. Cancer Res 2018; 78:4396-4410. [PMID: 29844118 DOI: 10.1158/0008-5472.can-17-2698] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Revised: 02/26/2018] [Accepted: 05/21/2018] [Indexed: 11/16/2022]
Abstract
Cancer cell lines differ greatly in their sensitivity to anticancer drugs as a result of different oncogenic drivers and drug resistance mechanisms operating in each cell line. Although many of these mechanisms have been discovered, it remains a challenge to understand how they interact to render an individual cell line sensitive or resistant to a particular drug. To better understand this variability, we profiled a panel of 30 breast cancer cell lines in the absence of drugs for their mutations, copy number aberrations, mRNA, protein expression and protein phosphorylation, and for response to seven different kinase inhibitors. We then constructed a knowledge-based, Bayesian computational model that integrates these data types and estimates the relative contribution of various drug sensitivity mechanisms. The resulting model of regulatory signaling explained the majority of the variability observed in drug response. The model also identified cell lines with an unexplained response, and for these we searched for novel explanatory factors. Among others, we found that 4E-BP1 protein expression, and not just the extent of phosphorylation, was a determinant of mTOR inhibitor sensitivity. We validated this finding experimentally and found that overexpression of 4E-BP1 in cell lines that normally possess low levels of this protein is sufficient to increase mTOR inhibitor sensitivity. Taken together, our work demonstrates that combining experimental characterization with integrative modeling can be used to systematically test and extend our understanding of the variability in anticancer drug response.Significance: By estimating how different oncogenic mutations and drug resistance mechanisms affect the response of cancer cells to kinase inhibitors, we can better understand and ultimately predict response to these anticancer drugs.Graphical Abstract: http://cancerres.aacrjournals.org/content/canres/78/15/4396/F1.large.jpg Cancer Res; 78(15); 4396-410. ©2018 AACR.
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Affiliation(s)
- Katarzyna Jastrzebski
- Division of Molecular Carcinogenesis, The Netherlands Cancer Institute, Amsterdam, the Netherlands
| | - Bram Thijssen
- Division of Molecular Carcinogenesis, The Netherlands Cancer Institute, Amsterdam, the Netherlands.,Oncode Institute, The Netherlands Cancer Institute, Amsterdam, the Netherlands
| | - Roelof J C Kluin
- Genomic Sequencing Facility, The Netherlands Cancer Institute, Amsterdam, the Netherlands
| | - Klaas de Lint
- Division of Molecular Carcinogenesis, The Netherlands Cancer Institute, Amsterdam, the Netherlands
| | - Ian J Majewski
- Division of Cancer and Haematology, The Walter and Eliza Hall Institute, Parkville Victoria, Australia
| | - Roderick L Beijersbergen
- Division of Molecular Carcinogenesis, The Netherlands Cancer Institute, Amsterdam, the Netherlands.
| | - Lodewyk F A Wessels
- Division of Molecular Carcinogenesis, The Netherlands Cancer Institute, Amsterdam, the Netherlands. .,Oncode Institute, The Netherlands Cancer Institute, Amsterdam, the Netherlands.,Faculty of EEMCS, Delft University of Technology, Delft, the Netherlands
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24
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Adamska A, Elaskalani O, Emmanouilidi A, Kim M, Abdol Razak NB, Metharom P, Falasca M. Molecular and cellular mechanisms of chemoresistance in pancreatic cancer. Adv Biol Regul 2018; 68:77-87. [PMID: 29221990 DOI: 10.1016/j.jbior.2017.11.007] [Citation(s) in RCA: 119] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Accepted: 11/21/2017] [Indexed: 02/07/2023]
Abstract
Pancreatic Ductal Adenocarcinoma (PDAC) is one of the most chemoresistant cancers, and current therapies targeting cancer-associated molecular pathways have not given satisfactory results, owing in part to rapid upregulation of alternative compensatory pathways. Most of the available treatments are palliative, focussing on improving the quality of life. At present, available options are surgery, embolization, radiation, chemotherapy, immunotherapy and use of other more targeted drugs. In this review, we describe the cellular and molecular effects of current chemotherapy drugs such as gemcitabine, FOLFIRINOX (5-fluorouracil [5-FU], oxaliplatin, irinotecan, and leucovorin) and ABRAXANE (nab-Paclitaxel), which have shown a survival benefit, although modest, for pancreatic cancer patients. Nevertheless, gemcitabine remains the standard first-line option for advanced-stage pancreatic cancer patients and, as resistance to the drug has attracted an increasing scientific interest, we deliberate on the main intracellular processes and proteins vital in acquired chemoresistance to gemcitabine. Lastly, our review examines various microenvironmental factors capable of instigating PDAC to develop resistance to chemotherapeutic drugs.
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Affiliation(s)
- Aleksandra Adamska
- Metabolic Signalling Group, School of Biomedical Sciences, Curtin Health Innovation Research Institute, Faculty of Health Sciences, Curtin University, Perth, Western Australia 6102, Australia
| | - Omar Elaskalani
- Platelet Research Laboratory, Curtin Health Innovation and Research Institute, Faculty of Health Sciences, Curtin University, Perth, Western Australia 6102, Australia
| | - Aikaterini Emmanouilidi
- Metabolic Signalling Group, School of Biomedical Sciences, Curtin Health Innovation Research Institute, Faculty of Health Sciences, Curtin University, Perth, Western Australia 6102, Australia
| | - Minkyoung Kim
- Metabolic Signalling Group, School of Biomedical Sciences, Curtin Health Innovation Research Institute, Faculty of Health Sciences, Curtin University, Perth, Western Australia 6102, Australia
| | - Norbaini Binti Abdol Razak
- Platelet Research Laboratory, Curtin Health Innovation and Research Institute, Faculty of Health Sciences, Curtin University, Perth, Western Australia 6102, Australia
| | - Pat Metharom
- Platelet Research Laboratory, Curtin Health Innovation and Research Institute, Faculty of Health Sciences, Curtin University, Perth, Western Australia 6102, Australia
| | - Marco Falasca
- Metabolic Signalling Group, School of Biomedical Sciences, Curtin Health Innovation Research Institute, Faculty of Health Sciences, Curtin University, Perth, Western Australia 6102, Australia.
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25
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Abstract
Mechanistic target of rapamycin (mTOR) is the kinase subunit of two structurally and functionally distinct large multiprotein complexes, referred to as mTOR complex 1 (mTORC1) and mTORC2. mTORC1 and mTORC2 play key physiological roles as they control anabolic and catabolic processes in response to external cues in a variety of tissues and organs. However, mTORC1 and mTORC2 activities are deregulated in widespread human diseases, including cancer. Cancer cells take advantage of mTOR oncogenic signaling to drive their proliferation, survival, metabolic transformation, and metastatic potential. Therefore, mTOR lends itself very well as a therapeutic target for innovative cancer treatment. mTOR was initially identified as the target of the antibiotic rapamycin that displayed remarkable antitumor activity in vitro Promising preclinical studies using rapamycin and its derivatives (rapalogs) demonstrated efficacy in many human cancer types, hence supporting the launch of numerous clinical trials aimed to evaluate the real effectiveness of mTOR-targeted therapies. However, rapamycin and rapalogs have shown very limited activity in most clinical contexts, also when combined with other drugs. Thus, novel classes of mTOR inhibitors with a stronger antineoplastic potency have been developed. Nevertheless, emerging clinical data suggest that also these novel mTOR-targeting drugs may have a weak antitumor activity. Here, we summarize the current status of available mTOR inhibitors and highlight the most relevant results from both preclinical and clinical studies that have provided valuable insights into both their efficacy and failure.
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26
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Wang J, Ye Q, Cao Y, Guo Y, Huang X, Mi W, Liu S, Wang C, Yang HS, Zhou BP, Evers BM, She QB. Snail determines the therapeutic response to mTOR kinase inhibitors by transcriptional repression of 4E-BP1. Nat Commun 2017; 8:2207. [PMID: 29263324 PMCID: PMC5738350 DOI: 10.1038/s41467-017-02243-3] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2016] [Accepted: 11/15/2017] [Indexed: 12/20/2022] Open
Abstract
Loss of 4E-BP1 expression has been linked to cancer progression and resistance to mTOR inhibitors, but the mechanism underlying 4E-BP1 downregulation in tumors remains unclear. Here we identify Snail as a strong transcriptional repressor of 4E-BP1. We find that 4E-BP1 expression inversely correlates with Snail level in cancer cell lines and clinical specimens. Snail binds to three E-boxes present in the human 4E-BP1 promoter to repress transcription of 4E-BP1. Ectopic expression of Snail in cancer cell lines lacking Snail profoundly represses 4E-BP1 expression, promotes cap-dependent translation in polysomes, and reduces the anti-proliferative effect of mTOR kinase inhibitors. Conversely, genetic and pharmacological inhibition of Snail function restores 4E-BP1 expression and sensitizes cancer cells to mTOR kinase inhibitors by enhancing 4E-BP1-mediated translation-repressive effect on cell proliferation and tumor growth. Our study reveals a critical Snail-4E-BP1 signaling axis in tumorigenesis, and provides a rationale for targeting Snail to improve mTOR-targeted therapies. 4E-BP1 is a translational repressor critical in mTOR signaling, whereas Snail is a critical promoter of epithelial to mesenchymal transition. Here the authors show that Snail induces resistance to mTOR inhibitors by repressing 4E-BP1 expression and promoting cell cycle progression via upregulating cycD.
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Affiliation(s)
- Jun Wang
- Markey Cancer Center, University of Kentucky College of Medicine, Lexington, KY, 40506, USA.,Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, KY, 40506, USA
| | - Qing Ye
- Markey Cancer Center, University of Kentucky College of Medicine, Lexington, KY, 40506, USA.,Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, KY, 40506, USA
| | - Yanan Cao
- Markey Cancer Center, University of Kentucky College of Medicine, Lexington, KY, 40506, USA.,Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, KY, 40506, USA
| | - Yubin Guo
- Markey Cancer Center, University of Kentucky College of Medicine, Lexington, KY, 40506, USA.,Guangdong Provincial Key Laboratory of Gastroenterology, Department of Gastroenterology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, 510515, China
| | - Xiuping Huang
- Markey Cancer Center, University of Kentucky College of Medicine, Lexington, KY, 40506, USA.,Guangdong Provincial Key Laboratory of Gastroenterology, Department of Gastroenterology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, 510515, China
| | - Wenting Mi
- Markey Cancer Center, University of Kentucky College of Medicine, Lexington, KY, 40506, USA.,Guangdong Provincial Key Laboratory of Gastroenterology, Department of Gastroenterology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, 510515, China
| | - Side Liu
- Guangdong Provincial Key Laboratory of Gastroenterology, Department of Gastroenterology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, 510515, China
| | - Chi Wang
- Markey Cancer Center, University of Kentucky College of Medicine, Lexington, KY, 40506, USA.,Department of Biostatistics, University of Kentucky College of Public Health, Lexington, KY, 40506, USA
| | - Hsin-Sheng Yang
- Markey Cancer Center, University of Kentucky College of Medicine, Lexington, KY, 40506, USA.,Department of Toxicology and Cancer Biology, University of Kentucky College of Medicine, Lexington, KY, 40506, USA
| | - Binhua P Zhou
- Markey Cancer Center, University of Kentucky College of Medicine, Lexington, KY, 40506, USA.,Department of Molecular and Cellular Biochemistry, University of Kentucky College of Medicine, Lexington, KY, 40506, USA
| | - B Mark Evers
- Markey Cancer Center, University of Kentucky College of Medicine, Lexington, KY, 40506, USA.,Department of Surgery, University of Kentucky College of Medicine, Lexington, KY, 40506, USA
| | - Qing-Bai She
- Markey Cancer Center, University of Kentucky College of Medicine, Lexington, KY, 40506, USA. .,Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, KY, 40506, USA.
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27
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Implication of 4E-BP1 protein dephosphorylation and accumulation in pancreatic cancer cell death induced by combined gemcitabine and TRAIL. Cell Death Dis 2017; 8:3204. [PMID: 29233971 PMCID: PMC5870593 DOI: 10.1038/s41419-017-0001-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2017] [Revised: 09/22/2017] [Accepted: 09/25/2017] [Indexed: 12/19/2022]
Abstract
Pancreatic cancer cells show varying sensitivity to the anticancer effects of gemcitabine. However, as a chemotherapeutic agent, gemcitabine can cause intolerably high levels of toxicity and patients often develop resistance to the beneficial effects of this drug. Combination studies show that use of gemcitabine with the pro-apoptotic cytokine TRAIL can enhance the inhibition of survival and induction of apoptosis of pancreatic cancer cells. Additionally, following combination treatment there is a dramatic increase in the level of the hypophosphorylated form of the tumour suppressor protein 4E-BP1. This is associated with inhibition of mTOR activity, resulting from caspase-mediated cleavage of the Raptor and Rictor components of mTOR. Use of the pan-caspase inhibitor Z-VAD-FMK indicates that the increase in level of 4E-BP1 is also caspase-mediated. ShRNA-silencing of 4E-BP1 expression renders cells more resistant to cell death induced by the combination treatment. Since the levels of 4E-BP1 are relatively low in untreated pancreatic cancer cells these results suggest that combined therapy with gemcitabine and TRAIL could improve the responsiveness of tumours to treatment by elevating the expression of 4E-BP1.
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28
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Survival of pancreatic cancer cells lacking KRAS function. Nat Commun 2017; 8:1090. [PMID: 29061961 PMCID: PMC5653666 DOI: 10.1038/s41467-017-00942-5] [Citation(s) in RCA: 117] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2017] [Accepted: 08/07/2017] [Indexed: 02/06/2023] Open
Abstract
Activating mutations in the proto-oncogene KRAS are a hallmark of pancreatic ductal adenocarcinoma (PDAC), an aggressive malignancy with few effective therapeutic options. Despite efforts to develop KRAS-targeted drugs, the absolute dependence of PDAC cells on KRAS remains incompletely understood. Here we model complete KRAS inhibition using CRISPR/Cas-mediated genome editing and demonstrate that KRAS is dispensable in a subset of human and mouse PDAC cells. Remarkably, nearly all KRAS deficient cells exhibit phosphoinositide 3-kinase (PI3K)-dependent mitogen-activated protein kinase (MAPK) signaling and induced sensitivity to PI3K inhibitors. Furthermore, comparison of gene expression profiles of PDAC cells retaining or lacking KRAS reveal a role of KRAS in the suppression of metastasis-related genes. Collectively, these data underscore the potential for PDAC resistance to even the very best KRAS inhibitors and provide insights into mechanisms of response and resistance to KRAS inhibition. Pancreatic cancer cells may develop resistance to KRAS inhibitors due to activation of compensatory pathways. In this study, the authors demonstrate that KRAS is dispensable in a subset of pancreatic cancer and that PI3K signalling may have an important role in mediating tumor growth following KRAS inhibition.
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29
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Matrine reduces the proliferation of A549 cells via the p53/p21/PCNA/eIF4E signaling pathway. Mol Med Rep 2017; 15:2415-2422. [PMID: 28447756 PMCID: PMC5428535 DOI: 10.3892/mmr.2017.6331] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2015] [Accepted: 04/19/2016] [Indexed: 11/16/2022] Open
Abstract
The aim of the present study was to investigate how matrine affects the proliferation of A549 human lung adenocarcinoma cells via the p53/p21/proliferating cell nuclear antigen (PCNA)/eukaryotic translation initiation factor 4E (eIF4E) signaling pathway. The effect of different concentrations of matrine on the proliferation of A549 cells was investigated using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The migration of A549 cells following exposure to varied concentrations of matrine was detected using a Transwell cell migration assay. The effect of 240 mg/l matrine on the apoptotic rate of A549 cells was determined using flow cytometry. The change in the mRNA and protein expression levels of p53, p21, PCNA and eIF4E following exposure to matrine were detected using reverse transcription-quantitative polymerase chain reaction and western blotting, respectively. The increase of matrine from 60–240 mg/l led to reduced cell migration and inhibition of A549 cell proliferation. The apoptotic rate of A549 cells when treated with 240 mg/l matrine was significantly different when compared with the untreated control. The mRNA expression levels of p53 and p21 in the group treated with 240 mg/l matrine were significantly higher compared with the control group. The mRNA expression levels of PCNA and eIF4E were significantly lower in the 240 mg/l matrine-treated group compared with the control. The protein expression levels of p53 and p21 were significantly higher in the 240 mg/l matrine group compared with the control group. Treatment with 240 mg/l matrine reduced the protein expression levels of PCNA and eIF4E. Matrine also reduced the migration ability of A549 cells and inhibited their proliferation, which may be associated with the overexpression of p53 and p21, and the reduction of PCNA and eIF4E expression levels.
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30
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Foley TM, Payne SN, Pasch CA, Yueh AE, Van De Hey DR, Korkos DP, Clipson L, Maher ME, Matkowskyj KA, Newton MA, Deming DA. Dual PI3K/mTOR Inhibition in Colorectal Cancers with APC and PIK3CA Mutations. Mol Cancer Res 2017; 15:317-327. [PMID: 28184015 PMCID: PMC5550373 DOI: 10.1158/1541-7786.mcr-16-0256] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Revised: 11/18/2016] [Accepted: 11/30/2016] [Indexed: 12/30/2022]
Abstract
Therapeutic targeting of the PI3K pathway is an active area of research in multiple cancer types, including breast and endometrial cancers. This pathway is commonly altered in cancer and plays an integral role in numerous vital cellular functions. Mutations in the PIK3CA gene, resulting in a constitutively active form of PI3K, often occur in colorectal cancer, though the population of patients who would benefit from targeting this pathway has yet to be identified. In human colorectal cancers, PIK3CA mutations most commonly occur concomitantly with loss of adenomatous polyposis coli (APC). Here, treatment strategies are investigated that target the PI3K pathway in colon cancers with mutations in APC and PIK3CA Colorectal cancer spheroids with Apc and Pik3ca mutations were generated and characterized confirming that these cultures represent the tumors from which they were derived. Pan and alpha isomer-specific PI3K inhibitors did not induce a significant treatment response, whereas the dual PI3K/mTOR inhibitors BEZ235 and LY3023414 induced a dramatic treatment response through decreased cellular proliferation and increased differentiation. The significant treatment responses were confirmed in mice with Apc and Pik3ca-mutant colon cancers as measured using endoscopy with a reduction in median lumen occlusion of 53% with BEZ235 and a 24% reduction with LY3023414 compared with an increase of 53% in controls (P < 0.001 and P = 0.03, respectively). This response was also confirmed with 18F-FDG microPET/CT imaging.Implications: Spheroid models and transgenic mice suggest that dual PI3K/mTOR inhibition is a potential treatment strategy for APC and PIK3CA-mutant colorectal cancers. Thus, further clinical studies of dual PI3K/mTOR inhibitors are warranted in colorectal cancers with these mutations. Mol Cancer Res; 15(3); 1-11. ©2016 AACR.
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Affiliation(s)
- Tyler M Foley
- Division of Hematology and Oncology, Department of Medicine, University of Wisconsin-Madison, Madison, Wisconsin
| | - Susan N Payne
- University of Wisconsin Carbone Cancer Center, Madison, Wisconsin
| | - Cheri A Pasch
- University of Wisconsin Carbone Cancer Center, Madison, Wisconsin
| | - Alex E Yueh
- Division of Hematology and Oncology, Department of Medicine, University of Wisconsin-Madison, Madison, Wisconsin
| | - Dana R Van De Hey
- Division of Hematology and Oncology, Department of Medicine, University of Wisconsin-Madison, Madison, Wisconsin
| | - Demetra P Korkos
- Division of Hematology and Oncology, Department of Medicine, University of Wisconsin-Madison, Madison, Wisconsin
| | - Linda Clipson
- McArdle Laboratory for Cancer Research, Department of Oncology, University of Wisconsin-Madison, Madison, Wisconsin
| | - Molly E Maher
- Division of Hematology and Oncology, Department of Medicine, University of Wisconsin-Madison, Madison, Wisconsin
| | - Kristina A Matkowskyj
- University of Wisconsin Carbone Cancer Center, Madison, Wisconsin
- Department of Pathology and Laboratory Medicine, University of Wisconsin-Madison, Madison, Wisconsin
- William S Middleton Memorial Veterans Hospital, Madison, Wisconsin
| | - Michael A Newton
- Departments of Statistics and of Biostatistics and Medical Informatics, University of Wisconsin-Madison, Madison, Wisconsin
| | - Dustin A Deming
- Division of Hematology and Oncology, Department of Medicine, University of Wisconsin-Madison, Madison, Wisconsin.
- University of Wisconsin Carbone Cancer Center, Madison, Wisconsin
- McArdle Laboratory for Cancer Research, Department of Oncology, University of Wisconsin-Madison, Madison, Wisconsin
- William S Middleton Memorial Veterans Hospital, Madison, Wisconsin
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31
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Gordeev SA, Bykova TV, Zubova SG, Bystrova OA, Martynova MG, Pospelov VA, Pospelova TV. mTOR kinase inhibitor pp242 causes mitophagy terminated by apoptotic cell death in E1A-Ras transformed cells. Oncotarget 2016; 6:44905-26. [PMID: 26636543 PMCID: PMC4792600 DOI: 10.18632/oncotarget.6457] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Accepted: 11/28/2015] [Indexed: 01/07/2023] Open
Abstract
mTOR is a critical target for controlling cell cycle progression, senescence and cell death in mammalian cancer cells. Here we studied the role of mTOR-dependent autophagy in implementating the antiprolifrative effect of mTORC1-specific inhibitor rapamycin and ATP-competitive mTOR kinase inhibitor pp242. We carried out a comprehensive analysis of pp242- and rapamycin-induced autophagy in ERas tumor cells. Rapamycin exerts cytostatic effect on ERas tumor cells, thus causing a temporary and reversible cell cycle arrest, activation of non-selective autophagy not accompanied by cell death. The rapamycin-treated cells are able to continue proliferation after drug removal. The ATP-competitive mTORC1/mTORC2 kinase inhibitor pp242 is highly cytotoxic by suppressing the function of mTORC1-4EBP1 axis and mTORC1-dependent phosphorylation of mTORC1 target--ULK1-Ser757 (Atg1). In contrast to rapamycin, pp242 activates the selective autophagy targeting mitochondria (mitophagy). The pp242-induced mitophagy is accompanied by accumulation of LC3 and conversion of LC3-I form to LC3-II. However reduced degradation of p62/SQSTM indicates abnormal flux of autophagic process. According to transmission electron microscopy data, short-term pp242-treated ERas cells exhibit numerous heavily damaged mitochondria, which are included in single membrane-bound autophagic/autolysophagic vacuoles (mitophagy). Despite the lack of typical for apoptosis features, ERas-treated cells with induced mitophagy revealed the activation of caspase 3, 9 and nucleosomal DNA fragmentation. Thus, pp242 activates autophagy with suppressed later stages, leading to impaired recycling and accumulation of dysfunctional mitochondria and cell death. Better understanding of how autophagy determines the fate of a cell--survival or cell death, can help to development of new strategy for cancer therapy.
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Affiliation(s)
- Serguei A Gordeev
- Institute of Cytology, Russian Academy of Sciences, St. Petersburg, Russia.,Saint Petersburg State University, St. Petersburg, Russia
| | - Tatiana V Bykova
- Institute of Cytology, Russian Academy of Sciences, St. Petersburg, Russia.,Saint Petersburg State University, St. Petersburg, Russia
| | - Svetlana G Zubova
- Institute of Cytology, Russian Academy of Sciences, St. Petersburg, Russia
| | - Olga A Bystrova
- Institute of Cytology, Russian Academy of Sciences, St. Petersburg, Russia
| | - Marina G Martynova
- Institute of Cytology, Russian Academy of Sciences, St. Petersburg, Russia
| | - Valery A Pospelov
- Institute of Cytology, Russian Academy of Sciences, St. Petersburg, Russia
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32
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4EBP-Dependent Signaling Supports West Nile Virus Growth and Protein Expression. Viruses 2016; 8:v8100287. [PMID: 27763553 PMCID: PMC5086619 DOI: 10.3390/v8100287] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Revised: 09/16/2016] [Accepted: 10/07/2016] [Indexed: 12/24/2022] Open
Abstract
West Nile virus (WNV) is a (+) sense, single-stranded RNA virus in the Flavivirus genus. WNV RNA possesses an m7GpppNm 5' cap with 2'-O-methylation that mimics host mRNAs preventing innate immune detection and allowing the virus to translate its RNA genome through the utilization of cap-dependent translation initiation effectors in a wide variety of host species. Our prior work established the requirement of the host mammalian target of rapamycin complex 1 (mTORC1) for optimal WNV growth and protein expression; yet, the roles of the downstream effectors of mTORC1 in WNV translation are unknown. In this study, we utilize gene deletion mutants in the ribosomal protein kinase called S6 kinase (S6K) and eukaryotic translation initiation factor 4E-binding protein (4EBP) pathways downstream of mTORC1 to define the role of mTOR-dependent translation initiation signals in WNV gene expression and growth. We now show that WNV growth and protein expression are dependent on mTORC1 mediated-regulation of the eukaryotic translation initiation factor 4E-binding protein/eukaryotic translation initiation factor 4E-binding protein (4EBP/eIF4E) interaction and eukaryotic initiation factor 4F (eIF4F) complex formation to support viral growth and viral protein expression. We also show that the canonical signals of mTORC1 activation including ribosomal protein s6 (rpS6) and S6K phosphorylation are not required for WNV growth in these same conditions. Our data suggest that the mTORC1/4EBP/eIF4E signaling axis is activated to support the translation of the WNV genome.
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33
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Purushottamachar P, Murigi FN, Njar VCO. Improved Procedures for Gram-Scale Synthesis of Galeterone 3β-Imidazole and Galeterone 3β-Pyridine Methoxylate, Potent Androgen Receptor/Mnk Degrading Agents. Org Process Res Dev 2016. [DOI: 10.1021/acs.oprd.6b00217] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Puranik Purushottamachar
- Department of Pharmacology, ‡Center for Biomolecular Therapeutics, and §Marlene and Stewart Greenebaum Comprehensive Cancer Center, University of Maryland School of Medicine, 685 West Baltimore Street, Baltimore, Maryland 21201-1559, United States
| | - Francis N. Murigi
- Department of Pharmacology, ‡Center for Biomolecular Therapeutics, and §Marlene and Stewart Greenebaum Comprehensive Cancer Center, University of Maryland School of Medicine, 685 West Baltimore Street, Baltimore, Maryland 21201-1559, United States
| | - Vincent C. O. Njar
- Department of Pharmacology, ‡Center for Biomolecular Therapeutics, and §Marlene and Stewart Greenebaum Comprehensive Cancer Center, University of Maryland School of Medicine, 685 West Baltimore Street, Baltimore, Maryland 21201-1559, United States
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Moatassim-Billah S, Duluc C, Samain R, Jean C, Perraud A, Decaup E, Cassant-Sourdy S, Bakri Y, Selves J, Schmid H, Martineau Y, Mathonnet M, Pyronnet S, Bousquet C. Anti-metastatic potential of somatostatin analog SOM230: Indirect pharmacological targeting of pancreatic cancer-associated fibroblasts. Oncotarget 2016; 7:41584-41598. [PMID: 27177087 PMCID: PMC5173080 DOI: 10.18632/oncotarget.9296] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Accepted: 03/31/2016] [Indexed: 12/26/2022] Open
Abstract
Pancreatic ductal adenocarcinoma (PDA) shows a rich stroma where cancer-associated fibroblasts (CAFs) represent the major cell type. CAFs are master secretors of proteins with pro-tumor features. CAF targeting remains a promising challenge for PDA, a devastating disease where treatments focusing on cancer cells have failed. We previously introduced a novel pharmacological CAF-targeting approach using the somatostatin analog SOM230 (pasireotide) that inhibits protein synthesis in CAFs, and subsequent chemoprotective features of CAF secretome. Using primary cultures of CAF isolated from human PDA resections, we here report that CAF secretome stimulates in vitro cancer cell survival, migration and invasive features, that are abolished when CAFs are treated with SOM230. Mechanistically, SOM230 inhibitory effect on CAFs depends on the somatostatin receptor subtype sst1 expressed in CAFs but not in non-activated pancreatic fibroblasts, and on protein synthesis shutdown through eiF4E-Binding Protein-1 (4E-BP1) expression decrease. We identify interleukin-6 as a SOM230-inhibited CAF-secreted effector, which stimulates cancer cell features through phosphoinositide 3-kinase activation. In vivo, mice orthotopically co-xenografted with the human pancreatic cancer MiaPaCa-2 cells and CAFs develop pancreatic tumors, on which SOM230 treatment does not inhibit growth but abrogates metastasis. Consistently, CAF secretome stimulates epithelial-to-mesenchymal transition in cancer cells, which is reversed upon CAF treatment with SOM230. Our results highlight a novel promising anti-metastatic potential for SOM230 indirectly targeting pancreatic cancer cell invasion through pharmacological inhibition of stromal CAFs.
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Affiliation(s)
- Siham Moatassim-Billah
- Cancer Research Center of Toulouse (CRCT), INSERM UMR 1037-University Toulouse III Paul Sabatier, Toulouse, France
- Biochemistry-Immunology Laboratory, Faculty of Sciences Rabat, University Mohammed V - Agdal, Rabat, Morocco
| | - Camille Duluc
- Cancer Research Center of Toulouse (CRCT), INSERM UMR 1037-University Toulouse III Paul Sabatier, Toulouse, France
| | - Rémi Samain
- Cancer Research Center of Toulouse (CRCT), INSERM UMR 1037-University Toulouse III Paul Sabatier, Toulouse, France
| | - Christine Jean
- Cancer Research Center of Toulouse (CRCT), INSERM UMR 1037-University Toulouse III Paul Sabatier, Toulouse, France
| | - Aurélie Perraud
- EA 3842 Laboratory, Medicine and Pharmacy Faculties, Limoges University, Limoges, France
| | - Emilie Decaup
- Cancer Research Center of Toulouse (CRCT), INSERM UMR 1037-University Toulouse III Paul Sabatier, Toulouse, France
| | - Stéphanie Cassant-Sourdy
- Cancer Research Center of Toulouse (CRCT), INSERM UMR 1037-University Toulouse III Paul Sabatier, Toulouse, France
| | - Youssef Bakri
- Biochemistry-Immunology Laboratory, Faculty of Sciences Rabat, University Mohammed V - Agdal, Rabat, Morocco
| | - Janick Selves
- Pathology Department, Institut Universitaire du Cancer de Toulouse, Toulouse, France
| | - Herbert Schmid
- Oncology Global Development, Novartis Pharmaceuticals, Basel, Switzerland
| | - Yvan Martineau
- Cancer Research Center of Toulouse (CRCT), INSERM UMR 1037-University Toulouse III Paul Sabatier, Toulouse, France
| | - Muriel Mathonnet
- EA 3842 Laboratory, Medicine and Pharmacy Faculties, Limoges University, Limoges, France
| | - Stéphane Pyronnet
- Cancer Research Center of Toulouse (CRCT), INSERM UMR 1037-University Toulouse III Paul Sabatier, Toulouse, France
| | - Corinne Bousquet
- Cancer Research Center of Toulouse (CRCT), INSERM UMR 1037-University Toulouse III Paul Sabatier, Toulouse, France
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35
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Bouquerel P, Gstalder C, Müller D, Laurent J, Brizuela L, Sabbadini RA, Malavaud B, Pyronnet S, Martineau Y, Ader I, Cuvillier O. Essential role for SphK1/S1P signaling to regulate hypoxia-inducible factor 2α expression and activity in cancer. Oncogenesis 2016; 5:e209. [PMID: 26974204 PMCID: PMC4815047 DOI: 10.1038/oncsis.2016.13] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Revised: 12/21/2015] [Accepted: 01/26/2016] [Indexed: 12/26/2022] Open
Abstract
The sphingosine kinase-1/sphingosine 1-phosphate (SphK1/S1P) signaling pathway has been reported to modulate the expression of the canonical transcription factor hypoxia-inducible HIF-1α in multiple cell lineages. HIF-2α is also frequently overexpressed in solid tumors but its role has been mostly studied in clear cell renal cell carcinoma (ccRCC), the most common form of kidney cancer, where HIF-2α has been established as a driver of a more aggressive disease. In this study, the role of SphK1/S1P signaling with regard to HIF-2α was investigated in various cancer cell models including ccRCC cells. Under hypoxic conditions or in ccRCC lacking a functional von Hippel-Lindau (VHL) gene and expressing high levels of HIF-2α, SphK1 activity controls HIF-2α expression and transcriptional activity through a phospholipase D (PLD)-driven mechanism. SphK1 silencing promotes a VHL-independent HIF-2α loss of expression and activity and reduces cell proliferation in ccRCC. Importantly, downregulation of SphK1 is associated with impaired Akt and mTOR signaling in ccRCC. Taking advantage of a monoclonal antibody neutralizing extracellular S1P, we show that inhibition of S1P extracellular signaling blocks HIF-2α accumulation in ccRCC cell lines, an effect mimicked when the S1P transporter Spns2 or the S1P receptor 1 (S1P1) is silenced. Here, we report the first evidence that the SphK1/S1P signaling pathway regulates the transcription factor hypoxia-inducible HIF-2α in diverse cancer cell lineages notably ccRCC, where HIF-2α has been established as a driver of a more aggressive disease. These findings demonstrate that SphK1/S1P signaling may act as a canonical regulator of HIF-2α expression in ccRCC, giving support to its inhibition as a therapeutic strategy that could contribute to reduce HIF-2 activity in ccRCC.
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Affiliation(s)
- P Bouquerel
- CNRS, Institut de Pharmacologie et de Biologie Structurale, Toulouse, France.,Université de Toulouse, UPS, IPBS, Toulouse, France.,Equipe Labellisée Ligue contre le Cancer, Toulouse, France
| | - C Gstalder
- CNRS, Institut de Pharmacologie et de Biologie Structurale, Toulouse, France.,Université de Toulouse, UPS, IPBS, Toulouse, France.,Equipe Labellisée Ligue contre le Cancer, Toulouse, France
| | - D Müller
- Equipe Labellisée Ligue contre le Cancer, Toulouse, France.,Laboratoire d'Excellence Toulouse Cancer (TOUCAN), INSERM UMR-1037, Cancer Research Center of Toulouse (CRCT), Université de Toulouse, Toulouse, France
| | - J Laurent
- CNRS, Institut de Pharmacologie et de Biologie Structurale, Toulouse, France.,Université de Toulouse, UPS, IPBS, Toulouse, France.,Equipe Labellisée Ligue contre le Cancer, Toulouse, France
| | - L Brizuela
- CNRS, Institut de Pharmacologie et de Biologie Structurale, Toulouse, France.,Université de Toulouse, UPS, IPBS, Toulouse, France.,Equipe Labellisée Ligue contre le Cancer, Toulouse, France
| | | | - B Malavaud
- CNRS, Institut de Pharmacologie et de Biologie Structurale, Toulouse, France.,Université de Toulouse, UPS, IPBS, Toulouse, France.,Equipe Labellisée Ligue contre le Cancer, Toulouse, France.,Institut Universitaire du Cancer Toulouse Oncopôle, Toulouse, France
| | - S Pyronnet
- Equipe Labellisée Ligue contre le Cancer, Toulouse, France.,Laboratoire d'Excellence Toulouse Cancer (TOUCAN), INSERM UMR-1037, Cancer Research Center of Toulouse (CRCT), Université de Toulouse, Toulouse, France
| | - Y Martineau
- Laboratoire d'Excellence Toulouse Cancer (TOUCAN), INSERM UMR-1037, Cancer Research Center of Toulouse (CRCT), Université de Toulouse, Toulouse, France
| | - I Ader
- CNRS, Institut de Pharmacologie et de Biologie Structurale, Toulouse, France.,Université de Toulouse, UPS, IPBS, Toulouse, France.,Equipe Labellisée Ligue contre le Cancer, Toulouse, France
| | - O Cuvillier
- CNRS, Institut de Pharmacologie et de Biologie Structurale, Toulouse, France.,Université de Toulouse, UPS, IPBS, Toulouse, France.,Equipe Labellisée Ligue contre le Cancer, Toulouse, France
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36
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Duluc C, Moatassim-Billah S, Chalabi-Dchar M, Perraud A, Samain R, Breibach F, Gayral M, Cordelier P, Delisle MB, Bousquet-Dubouch MP, Tomasini R, Schmid H, Mathonnet M, Pyronnet S, Martineau Y, Bousquet C. Pharmacological targeting of the protein synthesis mTOR/4E-BP1 pathway in cancer-associated fibroblasts abrogates pancreatic tumour chemoresistance. EMBO Mol Med 2016; 7:735-53. [PMID: 25834145 PMCID: PMC4459815 DOI: 10.15252/emmm.201404346] [Citation(s) in RCA: 153] [Impact Index Per Article: 19.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Pancreatic ductal adenocarcinoma (PDAC) is extremely stroma-rich. Cancer-associated fibroblasts (CAFs) secrete proteins that activate survival and promote chemoresistance of cancer cells. Our results demonstrate that CAF secretome-triggered chemoresistance is abolished upon inhibition of the protein synthesis mTOR/4E-BP1 regulatory pathway which we found highly activated in primary cultures of α-SMA-positive CAFs, isolated from human PDAC resections. CAFs selectively express the sst1 somatostatin receptor. The SOM230 analogue (Pasireotide) activates the sst1 receptor and inhibits the mTOR/4E-BP1 pathway and the resultant synthesis of secreted proteins including IL-6. Consequently, tumour growth and chemoresistance in nude mice xenografted with pancreatic cancer cells and CAFs, or with pieces of resected human PDACs, are reduced when chemotherapy (gemcitabine) is combined with SOM230 treatment. While gemcitabine alone has marginal effects, SOM230 is permissive to gemcitabine-induced cancer cell apoptosis and acts as an antifibrotic agent. We propose that selective inhibition of CAF protein synthesis with sst1-directed pharmacological compounds represents an anti-stromal-targeted therapy with promising chemosensitization potential.
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Affiliation(s)
- Camille Duluc
- INSERM UMR-1037, Cancer Research Center of Toulouse (CRCT), Equipe labellisée Ligue Contre le Cancer and Laboratoire d'Excellence Toulouse Cancer (TOUCAN), Université de Toulouse, Toulouse, France
| | - Siham Moatassim-Billah
- INSERM UMR-1037, Cancer Research Center of Toulouse (CRCT), Equipe labellisée Ligue Contre le Cancer and Laboratoire d'Excellence Toulouse Cancer (TOUCAN), Université de Toulouse, Toulouse, France Biochemistry-Immunology Laboratory, Faculty of Sciences Rabat, University Mohammed V - Agdal, Agdal, Morocco
| | - Mounira Chalabi-Dchar
- INSERM UMR-1037, Cancer Research Center of Toulouse (CRCT), Equipe labellisée Ligue Contre le Cancer and Laboratoire d'Excellence Toulouse Cancer (TOUCAN), Université de Toulouse, Toulouse, France
| | - Aurélie Perraud
- EA 3842 Laboratory, Medicine and Pharmacy Faculties, Limoges University, Limoges, France
| | - Rémi Samain
- INSERM UMR-1037, Cancer Research Center of Toulouse (CRCT), Equipe labellisée Ligue Contre le Cancer and Laboratoire d'Excellence Toulouse Cancer (TOUCAN), Université de Toulouse, Toulouse, France
| | | | - Marion Gayral
- INSERM UMR-1037, Cancer Research Center of Toulouse (CRCT), Equipe labellisée Ligue Contre le Cancer and Laboratoire d'Excellence Toulouse Cancer (TOUCAN), Université de Toulouse, Toulouse, France
| | - Pierre Cordelier
- INSERM UMR-1037, Cancer Research Center of Toulouse (CRCT), Equipe labellisée Ligue Contre le Cancer and Laboratoire d'Excellence Toulouse Cancer (TOUCAN), Université de Toulouse, Toulouse, France
| | | | - Marie-Pierre Bousquet-Dubouch
- CNRS UMR-5089, Institut de Pharmacologie et de Biologie structurale (IPBS), Université de Toulouse, Toulouse, France
| | - Richard Tomasini
- CRCM, INSERM, U1068; Paoli-Calmettes Institute; Aix-Marseille University, UM105; CNRS, UMR7258, Marseille, France
| | | | - Muriel Mathonnet
- EA 3842 Laboratory, Medicine and Pharmacy Faculties, Limoges University, Limoges, France
| | - Stéphane Pyronnet
- INSERM UMR-1037, Cancer Research Center of Toulouse (CRCT), Equipe labellisée Ligue Contre le Cancer and Laboratoire d'Excellence Toulouse Cancer (TOUCAN), Université de Toulouse, Toulouse, France
| | - Yvan Martineau
- INSERM UMR-1037, Cancer Research Center of Toulouse (CRCT), Equipe labellisée Ligue Contre le Cancer and Laboratoire d'Excellence Toulouse Cancer (TOUCAN), Université de Toulouse, Toulouse, France
| | - Corinne Bousquet
- INSERM UMR-1037, Cancer Research Center of Toulouse (CRCT), Equipe labellisée Ligue Contre le Cancer and Laboratoire d'Excellence Toulouse Cancer (TOUCAN), Université de Toulouse, Toulouse, France
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37
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Morita M, Gravel SP, Hulea L, Larsson O, Pollak M, St-Pierre J, Topisirovic I. mTOR coordinates protein synthesis, mitochondrial activity and proliferation. Cell Cycle 2015; 14:473-80. [PMID: 25590164 PMCID: PMC4615141 DOI: 10.4161/15384101.2014.991572] [Citation(s) in RCA: 343] [Impact Index Per Article: 38.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Protein synthesis is one of the most energy consuming processes in the cell. The mammalian/mechanistic target of rapamycin (mTOR) is a serine/threonine kinase that integrates a multitude of extracellular signals and intracellular cues to drive growth and proliferation. mTOR activity is altered in numerous pathological conditions, including metabolic syndrome and cancer. In addition to its well-established role in regulating mRNA translation, emerging studies indicate that mTOR modulates mitochondrial functions. In mammals, mTOR coordinates energy consumption by the mRNA translation machinery and mitochondrial energy production by stimulating synthesis of nucleus-encoded mitochondria-related proteins including TFAM, mitochondrial ribosomal proteins and components of complexes I and V. In this review, we highlight findings that link mTOR, mRNA translation and mitochondrial functions.
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Affiliation(s)
- Masahiro Morita
- a Department of Biochemistry and Goodman Cancer Research Centre ; McGill University ; Montreal , QC Canada
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38
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Kumar K, Chow CR, Ebine K, Arslan AD, Kwok B, Bentrem DJ, Eckerdt FD, Platanias LC, Munshi HG. Differential Regulation of ZEB1 and EMT by MAPK-Interacting Protein Kinases (MNK) and eIF4E in Pancreatic Cancer. Mol Cancer Res 2015; 14:216-27. [PMID: 26609108 DOI: 10.1158/1541-7786.mcr-15-0285] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Accepted: 11/15/2015] [Indexed: 02/07/2023]
Abstract
UNLABELLED Human pancreatic ductal adenocarcinoma (PDAC) tumors are associated with dysregulation of mRNA translation. In this report, it is demonstrated that PDAC cells grown in collagen exhibit increased activation of the MAPK-interacting protein kinases (MNK) that mediate eIF4E phosphorylation. Pharmacologic and genetic targeting of MNKs reverse epithelial-mesenchymal transition (EMT), decrease cell migration, and reduce protein expression of the EMT-regulator ZEB1 without affecting ZEB1 mRNA levels. Paradoxically, targeting eIF4E, the best-characterized effector of MNKs, increases ZEB1 mRNA expression through repression of ZEB1-targeting miRNAs, miR-200c and miR-141. In contrast, targeting the MNK effector hnRNPA1, which can function as a translational repressor, increases ZEB1 protein without increasing ZEB1 mRNA levels. Importantly, treatment with MNK inhibitors blocks growth of chemoresistant PDAC cells in collagen and decreases the number of aldehyde dehydrogenase activity-positive (Aldefluor+) cells. Significantly, MNK inhibitors increase E-cadherin mRNA levels and decrease vimentin mRNA levels in human PDAC organoids without affecting ZEB1 mRNA levels. Importantly, MNK inhibitors also decrease growth of human PDAC organoids. IMPLICATIONS These results demonstrate differential regulation of ZEB1 and EMT by MNKs and eIF4E, and identify MNKs as potential targets in pancreatic cancer.
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Affiliation(s)
- Krishan Kumar
- Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, Illinois. Jesse Brown VA Medical Center, Chicago, Illinois
| | - Christina R Chow
- Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, Illinois. The Robert H. Lurie Comprehensive Cancer Center of Northwestern University, Chicago, Illinois
| | - Kazumi Ebine
- Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, Illinois. Jesse Brown VA Medical Center, Chicago, Illinois
| | - Ahmet D Arslan
- Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, Illinois. The Robert H. Lurie Comprehensive Cancer Center of Northwestern University, Chicago, Illinois
| | - Benjamin Kwok
- Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - David J Bentrem
- Jesse Brown VA Medical Center, Chicago, Illinois. The Robert H. Lurie Comprehensive Cancer Center of Northwestern University, Chicago, Illinois. Department of Surgery, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - Frank D Eckerdt
- The Robert H. Lurie Comprehensive Cancer Center of Northwestern University, Chicago, Illinois
| | - Leonidas C Platanias
- Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, Illinois. Jesse Brown VA Medical Center, Chicago, Illinois. The Robert H. Lurie Comprehensive Cancer Center of Northwestern University, Chicago, Illinois
| | - Hidayatullah G Munshi
- Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, Illinois. Jesse Brown VA Medical Center, Chicago, Illinois. The Robert H. Lurie Comprehensive Cancer Center of Northwestern University, Chicago, Illinois.
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Liko D, Hall MN. mTOR in health and in sickness. J Mol Med (Berl) 2015; 93:1061-73. [DOI: 10.1007/s00109-015-1326-7] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2015] [Revised: 07/14/2015] [Accepted: 07/22/2015] [Indexed: 01/12/2023]
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Eukaryotic Translation Initiation Factor 4E Is a Feed-Forward Translational Coactivator of Transforming Growth Factor β Early Protransforming Events in Breast Epithelial Cells. Mol Cell Biol 2015; 35:2597-609. [PMID: 25986608 DOI: 10.1128/mcb.00324-15] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Accepted: 05/12/2015] [Indexed: 12/18/2022] Open
Abstract
Eukaryotic translation initiation factor 4E (eIF4E) is overexpressed early in breast cancers in association with disease progression and reduced survival. Much remains to be understood regarding the role of eIF4E in human cancer. We determined, using immortalized human breast epithelial cells, that elevated expression of eIF4E translationally activates the transforming growth factor β (TGF-β) pathway, promoting cell invasion, a loss of cell polarity, increased cell survival, and other hallmarks of early neoplasia. Overexpression of eIF4E is shown to facilitate the selective translation of integrin β1 mRNA, which drives the translationally controlled assembly of a TGF-β receptor signaling complex containing α3β1 integrins, β-catenin, TGF-β receptor I, E-cadherin, and phosphorylated Smad2/3. This receptor complex acutely sensitizes nonmalignant breast epithelial cells to activation by typically substimulatory levels of activated TGF-β. TGF-β can promote cellular differentiation or invasion and transformation. As a translational coactivator of TGF-β, eIF4E confers selective mRNA translation, reprogramming nonmalignant cells to an invasive phenotype by reducing the set point for stimulation by activated TGF-β. Overexpression of eIF4E may be a proinvasive facilitator of TGF-β activity.
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41
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Imbalanced splicing in MAPK signaling sustains Ras-induced transformation. Clin Res Hepatol Gastroenterol 2015; 39:155-6. [PMID: 25468550 DOI: 10.1016/j.clinre.2014.09.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Revised: 09/25/2014] [Accepted: 09/29/2014] [Indexed: 02/04/2023]
Abstract
Increasingly, evidence suggests that phosphorylation of the mRNA translation initiation factor eIF4E plays an important role in carcinogenesis, downstream of Ras. The eIF4E factor is phosphorylated by MAPK-interacting protein kinases 1 and 2 (MNK1 and MNK2). Due to alternative splicing, two MNK2 proteins exist (MNK2a and MNK2b). While MNK2a possesses a binding site for the stress-induced p38-MAPK, MNK2b does not. Recently, Maimon et al. revealed that a splicing shift towards the MNK2b isoform, in Ras-activated cells, sustains transformation, due to a defect in p38-induced cell death, while the MNK2b-dependent phosphorylation of eIF4E is maintained.
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Abstract
Dysregulation of mRNA translation is a frequent feature of neoplasia. Many oncogenes and tumour suppressors affect the translation machinery, making aberrant translation a widespread characteristic of tumour cells, independent of the genetic make-up of the cancer. Therefore, therapeutic agents that target components of the protein synthesis apparatus hold promise as novel anticancer drugs that can overcome intra-tumour heterogeneity. In this Review, we discuss the role of translation in cancer, with a particular focus on the eIF4F (eukaryotic translation initiation factor 4F) complex, and provide an overview of recent efforts aiming to 'translate' these results to the clinic.
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Faller WJ, Jackson TJ, Knight JR, Ridgway RA, Jamieson T, Karim SA, Jones C, Radulescu S, Huels DJ, Myant KB, Dudek KM, Casey HA, Scopelliti A, Cordero JB, Vidal M, Pende M, Ryazanov AG, Sonenberg N, Meyuhas O, Hall MN, Bushell M, Willis AE, Sansom OJ. mTORC1-mediated translational elongation limits intestinal tumour initiation and growth. Nature 2015; 517:497-500. [PMID: 25383520 PMCID: PMC4304784 DOI: 10.1038/nature13896] [Citation(s) in RCA: 231] [Impact Index Per Article: 25.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2013] [Accepted: 09/26/2014] [Indexed: 12/31/2022]
Abstract
Inactivation of APC is a strongly predisposing event in the development of colorectal cancer, prompting the search for vulnerabilities specific to cells that have lost APC function. Signalling through the mTOR pathway is known to be required for epithelial cell proliferation and tumour growth, and the current paradigm suggests that a critical function of mTOR activity is to upregulate translational initiation through phosphorylation of 4EBP1 (refs 6, 7). This model predicts that the mTOR inhibitor rapamycin, which does not efficiently inhibit 4EBP1 (ref. 8), would be ineffective in limiting cancer progression in APC-deficient lesions. Here we show in mice that mTOR complex 1 (mTORC1) activity is absolutely required for the proliferation of Apc-deficient (but not wild-type) enterocytes, revealing an unexpected opportunity for therapeutic intervention. Although APC-deficient cells show the expected increases in protein synthesis, our study reveals that it is translation elongation, and not initiation, which is the rate-limiting component. Mechanistically, mTORC1-mediated inhibition of eEF2 kinase is required for the proliferation of APC-deficient cells. Importantly, treatment of established APC-deficient adenomas with rapamycin (which can target eEF2 through the mTORC1-S6K-eEF2K axis) causes tumour cells to undergo growth arrest and differentiation. Taken together, our data suggest that inhibition of translation elongation using existing, clinically approved drugs, such as the rapalogs, would provide clear therapeutic benefit for patients at high risk of developing colorectal cancer.
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Affiliation(s)
| | - Thomas J Jackson
- Medical Research Council Toxicology Unit; Leicester, LE1 9HN, UK
| | - John Rp Knight
- Medical Research Council Toxicology Unit; Leicester, LE1 9HN, UK
| | | | | | - Saadia A Karim
- Cancer Research UK Beatson Institute, Glasgow, G61 1BD, UK
| | - Carolyn Jones
- Medical Research Council Toxicology Unit; Leicester, LE1 9HN, UK
| | | | - David J Huels
- Cancer Research UK Beatson Institute, Glasgow, G61 1BD, UK
| | - Kevin B Myant
- Cancer Research UK Beatson Institute, Glasgow, G61 1BD, UK
| | - Kate M Dudek
- Medical Research Council Toxicology Unit; Leicester, LE1 9HN, UK
| | - Helen A Casey
- Cancer Research UK Beatson Institute, Glasgow, G61 1BD, UK
| | | | | | - Marcos Vidal
- Cancer Research UK Beatson Institute, Glasgow, G61 1BD, UK
| | - Mario Pende
- Inserm U845, Université Paris Descartes, Necker Medical School, 75015 Paris, France
| | - Alexey G Ryazanov
- Robert Wood Johnson Medical School, Department of Pharmacology, Piscataway, New Jersey, USA
| | - Nahum Sonenberg
- Department of Biochemistry and Goodman Cancer Research Center, McGill University, Montreal, QC H3A 1A3, Canada
| | - Oded Meyuhas
- Department of Biochemistry and Molecular Biology, IMRIC, The Hebrew University-Hadassah Medical School, Jerusalem 91120, Israel
| | - Michael N Hall
- Biozentrum, University of Basel, CH-4056 Basel, Switzerland
| | - Martin Bushell
- Medical Research Council Toxicology Unit; Leicester, LE1 9HN, UK
| | - Anne E Willis
- Medical Research Council Toxicology Unit; Leicester, LE1 9HN, UK
| | - Owen J Sansom
- Cancer Research UK Beatson Institute, Glasgow, G61 1BD, UK
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Wang C, Cigliano A, Jiang L, Li X, Fan B, Pilo MG, Liu Y, Gui B, Sini M, Smith JW, Dombrowski F, Calvisi DF, Evert M, Chen X. 4EBP1/eIF4E and p70S6K/RPS6 axes play critical and distinct roles in hepatocarcinogenesis driven by AKT and N-Ras proto-oncogenes in mice. Hepatology 2015; 61:200-13. [PMID: 25145583 PMCID: PMC4280310 DOI: 10.1002/hep.27396] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/25/2014] [Accepted: 08/20/2014] [Indexed: 12/16/2022]
Abstract
UNLABELLED Concomitant expression of activated forms of v-akt murine thymoma viral oncogene homolog (AKT) and Ras in mouse liver (AKT/Ras) leads to rapid tumor development through strong activation of the mammalian target of rapamycin complex 1 (mTORC1) pathway. mTORC1 functions by regulating p70S6K/ribosomal protein S6 (RPS6) and eukaryotic translation initiation factor 4E-binding protein 1/ eukaryotic translation initiation factor 4E (4EBP1/eIF4E) cascades. How these cascades contribute to hepatocarcinogenesis remains unknown. Here, we show that inhibition of the RPS6 pathway by rapamycin effectively suppressed, whereas blockade of the 4EBP1/eIF4E cascade by 4EBP1A4, an unphosphorylatable form of 4EBP1, significantly delayed, AKT/Ras-induced hepatocarcinogenesis. Combined treatment with rapamycin and 4EBP1A4 completely inhibited AKT/Ras hepatocarcinogenesis. This strong antineoplastic effect was successfully recapitulated by ablating regulatory associated protein of mTORC1, the major subunit of mTORC1, in AKT/Ras-overexpressing livers. Furthermore, we demonstrate that overexpression of eIF4E, the proto-oncogene whose activity is specifically inhibited by 4EBP1, resulted in hepatocellular carcinoma (HCC) development in cooperation with activated Ras. Mechanistically, we identified the ectonucleoside triphosphate diphosphohydrolase 5/ adenylate kinase 1/cytidine monophosphate kinase 1 axis and the mitochondrial biogenesis pathway as targets of the 4EBP1/eIF4E cascade in AKT/Ras and Ras/eIF4E livers as well as in human HCC cell lines and tissues. CONCLUSIONS Complete inhibition of mTORC1 is required to suppress liver cancer development induced by AKT and Ras proto-oncogenes in mice. The mTORC1 effectors, RPS6 and eIF4E, play distinct roles and are both necessary for AKT/Ras hepatocarcinogenesis. These new findings might open the way for innovative therapies against human HCC.
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Affiliation(s)
- Chunmei Wang
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, CA
| | - Antonio Cigliano
- Institute of Pathology, University of Greifswald, Greifswald, Germany
| | - Lijie Jiang
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, CA
| | - Xiaolei Li
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, CA,Department of Hepatobiliary Surgery, Xijing Hospital, The Fourth Military Medical University, Xi'an, Shaanxi 710032, P. R. China
| | - Biao Fan
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, CA
| | - Maria G. Pilo
- Institute of Pathology, University of Greifswald, Greifswald, Germany
| | - Yan Liu
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, CA
| | - Bing Gui
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, CA
| | - Marcella Sini
- Institute of Pathology, University of Greifswald, Greifswald, Germany
| | | | - Frank Dombrowski
- Institute of Pathology, University of Greifswald, Greifswald, Germany
| | - Diego F. Calvisi
- Institute of Pathology, University of Greifswald, Greifswald, Germany
| | - Matthias Evert
- Institute of Pathology, University of Greifswald, Greifswald, Germany
| | - Xin Chen
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, CA,Liver Center, University of California, San Francisco, CA
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45
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Chiarini F, Evangelisti C, McCubrey JA, Martelli AM. Current treatment strategies for inhibiting mTOR in cancer. Trends Pharmacol Sci 2014; 36:124-35. [PMID: 25497227 DOI: 10.1016/j.tips.2014.11.004] [Citation(s) in RCA: 209] [Impact Index Per Article: 20.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Revised: 11/07/2014] [Accepted: 11/12/2014] [Indexed: 02/07/2023]
Abstract
Mammalian target of rapamycin (mTOR) is a Ser/Thr kinase that regulates a wide range of functions, including cell growth, proliferation, survival, autophagy, metabolism, and cytoskeletal organization. mTOR activity is dysregulated in several human disorders, including cancer. The crucial role of mTOR in cancer cell biology has stimulated interest in mTOR inhibitors, placing mTOR on the radar of the pharmaceutical industry. Several mTOR inhibitors have already undergone clinical trials for treating tumors, without great success, although mTOR inhibitors are approved for the treatment of some types of cancer, including advanced renal cell carcinoma. However, the role of mTOR inhibitors in cancer treatment continues to evolve as new compounds are continuously being disclosed. Here we review the three classes of mTOR inhibitors currently available for treating cancer patients. Moreover, we highlight efforts to identify markers of resistance and sensitivity to mTOR inhibition that could prove useful in the emerging field of personalized medicine.
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Affiliation(s)
- Francesca Chiarini
- Institute of Molecular Genetics, National Research Council, Bologna, Italy; Rizzoli Orthopedic Institute, Bologna, Italy
| | - Camilla Evangelisti
- Institute of Molecular Genetics, National Research Council, Bologna, Italy; Rizzoli Orthopedic Institute, Bologna, Italy
| | - James A McCubrey
- Department of Microbiology and Immunology, Brody School of Medicine, East Carolina University, Greenville, NC, USA
| | - Alberto M Martelli
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy.
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47
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Abstract
The central role of phosphoinositide 3-kinase (PI3K) activation in tumour cell biology has prompted a sizeable effort to target PI3K and/or downstream kinases such as AKT and mammalian target of rapamycin (mTOR) in cancer. However, emerging clinical data show limited single-agent activity of inhibitors targeting PI3K, AKT or mTOR at tolerated doses. One exception is the response to PI3Kδ inhibitors in chronic lymphocytic leukaemia, where a combination of cell-intrinsic and -extrinsic activities drive efficacy. Here, we review key challenges and opportunities for the clinical development of inhibitors targeting the PI3K-AKT-mTOR pathway. Through a greater focus on patient selection, increased understanding of immune modulation and strategic application of rational combinations, it should be possible to realize the potential of this promising class of targeted anticancer agents.
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48
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p70S6 kinase is a critical node that integrates HER-family and PI3 kinase signaling networks. Cell Signal 2014; 26:1627-35. [PMID: 24662264 DOI: 10.1016/j.cellsig.2014.03.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2014] [Accepted: 03/10/2014] [Indexed: 12/17/2022]
Abstract
Therapies targeting oncogenic drivers rapidly induce compensatory adaptive responses that blunt drug effectiveness, contributing to therapeutic resistance. Adaptive responses are characteristic of robust cell signaling networks, and thus there is increasing interest in drug combinations that co-target the driver and the adaptive response. An alternative approach to co-inhibiting oncogenic and adaptive targets is to identify a critical node where the activities of these targets converge. Nodes of convergence between signaling modules represent potential therapeutic vulnerabilities because their inhibition could result in the collapse of the network, leading to enhanced cytotoxicity. In this report we demonstrate that p70S6 kinase (p70S6K) can function as a critical node linking HER-family and phosphoinositide-3-kinase (PI3K) pathway signaling. We used high-throughput combinatorial drug screening to identify adaptive survival responses to targeted therapies, and found that HER-family and PI3K represented compensatory signaling pathways. Co-targeting these pathways with drug combinations caused synergistic cytotoxicity in cases where inhibition of neither target was effective as a monotherapy. We utilized Reverse Phase Protein Arrays and determined that phosphorylation of ribosomal protein S6 was synergistically down-regulated upon HER-family and PI3K/mammalian target of rapamycin (mTOR) co-inhibition. Expression of constitutively active p70S6K protected against apoptosis induced by combined HER-family and PI3K/mTOR inhibition. Direct inhibition of p70S6K with small molecule inhibitors phenocopied HER-family and PI3K/mTOR co-inhibition. These data implicate p70S6K as a critical node in the HER-family/PI3K signaling network. The ability of direct inhibitors of p70S6K to phenocopy co-inhibition of two upstream signaling targets indicates that identification and targeting of critical nodes can overcome adaptive resistance to targeted therapies.
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49
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Resistance to mTOR kinase inhibitors in lymphoma cells lacking 4EBP1. PLoS One 2014; 9:e88865. [PMID: 24586420 PMCID: PMC3931643 DOI: 10.1371/journal.pone.0088865] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2013] [Accepted: 01/13/2014] [Indexed: 11/19/2022] Open
Abstract
Inhibitors of the mechanistic target of rapamycin (mTOR) hold promise for treatment of hematological malignancies. Analogs of the allosteric mTOR inhibitor rapamycin are approved for mantle cell lymphoma but have limited efficacy in other blood cancers. ATP-competitive "active-site" mTOR inhibitors produce more complete mTOR inhibition and are more effective than rapamycin in preclinical models of leukemia, lymphoma and multiple myeloma. In parallel to clinical trials of active-site mTOR inhibitors, it will be important to identify resistance mechanisms that might limit drug efficacy in certain patients. From a panel of diffuse large B-cell lymphoma cell lines, we found that the VAL cell line is particularly resistant to apoptosis in the presence of active-site mTOR inhibitors. Mechanistic investigation showed that VAL does not express eukaryotic initiation factor 4E-binding protein-1 (4EBP1), a key negative regulator of translation controlled by mTOR. Although VAL cells express the related protein 4EBP2, mTOR inhibitor treatment fails to displace eukaryotic initiation factor 4G from the mRNA cap-binding complex. Knockdown of eukaryotic initiation factor 4E, or re-expression of 4EBP1, sensitizes cells to apoptosis when treated with active-site mTOR inhibitors. These findings provide a naturally occurring example of 4EBP deficiency driving lymphoma cell resistance to active-site mTOR inhibitors.
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50
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Müller D, Lasfargues C, El Khawand S, Alard A, Schneider RJ, Bousquet C, Pyronnet S, Martineau Y. 4E-BP restrains eIF4E phosphorylation. ACTA ACUST UNITED AC 2013; 1:e25819. [PMID: 26824022 PMCID: PMC4718053 DOI: 10.4161/trla.25819] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2013] [Revised: 07/18/2013] [Accepted: 07/19/2013] [Indexed: 12/17/2022]
Abstract
In eukaryotes, mRNA translation is dependent on the cap-binding protein eIF4E. Through its simultaneous interaction with the mRNA cap structure and with the ribosome-associated eIF4G adaptor protein, eIF4E physically posits the ribosome at the 5' extremity of capped mRNA. eIF4E activity is regulated by phosphorylation on a unique site by the eIF4G-associated kinase MNK. eIF4E assembly with the eIF4G-MNK sub-complex can be however antagonized by the hypophosphorylated forms of eIF4E-binding protein (4E-BP). We show here that eIF4E phosphorylation is dramatically affected by disruption of eIF4E-eIF4G interaction, independently of changes in MNK expression. eIF4E phosphorylation is actually strongly downregulated upon eIF4G shutdown or upon sequestration by hypophosphorylated 4E-BP, consequent to mTOR inhibition. Downregulation of 4E-BP renders eIF4E phosphorylation insensitive to mTOR inhibition. These data highlight the important role of 4E-BP in regulating eIF4E phosphorylation independently of changes in MNK expression.
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Affiliation(s)
- David Müller
- INSERM UMR-1037; Toulouse University; Cancer Research Center of Toulouse (CRCT); Equipe Labellisée Ligue Contre le Cancer and Laboratoire d'Excellence Toulouse Cancer (TOUCAN); Toulouse, France
| | - Charline Lasfargues
- INSERM UMR-1037; Toulouse University; Cancer Research Center of Toulouse (CRCT); Equipe Labellisée Ligue Contre le Cancer and Laboratoire d'Excellence Toulouse Cancer (TOUCAN); Toulouse, France
| | - Sally El Khawand
- INSERM UMR-1037; Toulouse University; Cancer Research Center of Toulouse (CRCT); Equipe Labellisée Ligue Contre le Cancer and Laboratoire d'Excellence Toulouse Cancer (TOUCAN); Toulouse, France
| | - Amandine Alard
- New York University School of Medicine; New York, NY USA
| | | | - Corinne Bousquet
- INSERM UMR-1037; Toulouse University; Cancer Research Center of Toulouse (CRCT); Equipe Labellisée Ligue Contre le Cancer and Laboratoire d'Excellence Toulouse Cancer (TOUCAN); Toulouse, France
| | - Stéphane Pyronnet
- INSERM UMR-1037; Toulouse University; Cancer Research Center of Toulouse (CRCT); Equipe Labellisée Ligue Contre le Cancer and Laboratoire d'Excellence Toulouse Cancer (TOUCAN); Toulouse, France
| | - Yvan Martineau
- INSERM UMR-1037; Toulouse University; Cancer Research Center of Toulouse (CRCT); Equipe Labellisée Ligue Contre le Cancer and Laboratoire d'Excellence Toulouse Cancer (TOUCAN); Toulouse, France
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