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Yamamoto V, Ha DP, Liu Z, Huang M, Samanta S, Neamati N, Lee AS. GRP78 inhibitor YUM70 upregulates 4E-BP1 and suppresses c-MYC expression and viability of oncogenic c-MYC tumors. Neoplasia 2024; 55:101020. [PMID: 38991376 DOI: 10.1016/j.neo.2024.101020] [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: 04/03/2024] [Revised: 06/13/2024] [Accepted: 06/24/2024] [Indexed: 07/13/2024]
Abstract
The 78-kDa glucose regulated protein (GRP78) commonly upregulated in a wide variety of tumors is an important prognostic marker and a promising target for suppressing tumorigenesis and treatment resistance. While GRP78 is well established as a major endoplasmic reticulum (ER) chaperone with anti-apoptotic properties and a master regulator of the unfolded protein response, its new role as a regulator of oncoprotein expression is just emerging. MYC is dysregulated in about 70 % of human cancers and is the most commonly activated oncoprotein. However, despite recent advances, therapeutic targeting of MYC remains challenging. Here we identify GRP78 as a new target for suppression of MYC expression. Using multiple MYC-dependent cancer models including head and neck squamous cell carcinoma and their cisplatin-resistant clones, breast and pancreatic adenocarcinoma, our studies revealed that GRP78 knockdown by siRNA or inhibition of its activity by small molecule inhibitors (YUM70 or HA15) reduced c-MYC expression, leading to onset of apoptosis and loss of cell viability. This was observed in 2D cell culture, 3D spheroid and in xenograft models. Mechanistically, we determined that the suppression of c-MYC is at the post-transcriptional level and that YUM70 and HA15 treatment potently upregulated the eukaryotic translation inhibitor 4E-BP1, which targets eIF4E critical for c-MYC translation initiation. Furthermore, knock-down of 4E-BP1 via siRNA rescued YUM70-mediated c-MYC suppression. As YUM70 is also capable of suppressing N-MYC expression, this study offers a new approach to suppress MYC protein expression through knockdown or inhibition of GRP78.
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Affiliation(s)
- Vicky Yamamoto
- Department of Biochemistry and Molecular Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, United States; Norris Comprehensive Cancer Center, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, United States
| | - Dat P Ha
- Department of Biochemistry and Molecular Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, United States; Norris Comprehensive Cancer Center, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, United States
| | - Ze Liu
- Department of Biochemistry and Molecular Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, United States; Norris Comprehensive Cancer Center, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, United States
| | - Miller Huang
- Department of Pediatrics, Children's Hospital of Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, United States
| | - Soma Samanta
- Department of Medicinal Chemistry, College of Pharmacy, Rogel Cancer Center, University of Michigan, Ann Arbor, MI, United States
| | - Nouri Neamati
- Department of Medicinal Chemistry, College of Pharmacy, Rogel Cancer Center, University of Michigan, Ann Arbor, MI, United States
| | - Amy S Lee
- Department of Biochemistry and Molecular Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, United States; Norris Comprehensive Cancer Center, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, United States.
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2
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Samykannu G, Mariyappan N, Natarajan J. Molecular interaction and MD-simulations: investigation of Sizofiran as a promising anti-cancer agent targeting eIF4E in colorectal cancer. In Silico Pharmacol 2024; 12:33. [PMID: 38655099 PMCID: PMC11033251 DOI: 10.1007/s40203-024-00206-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2024] [Accepted: 03/28/2024] [Indexed: 04/26/2024] Open
Abstract
CRC has a major global health impact due to high mortality rates. CRC shows high expression of eukaryotic translation initiation factor (eIF4E) protein, the rapid development of lung, bladder, colon, prostate, breast, head, and neck cancer is attributed to the dysregulation of eIF4E making an important target for treatment. Targeting eIF4E-mediated translation is a promising anti-cancer strategy. Many organic compounds that inhibit eIF4E are being studied clinically. The compound Sizofiran has emerged as a promising eIF4E inhibitor candidate, but its exact mechanism of action is unclear. In an effort to close this discrepancy by clarifying the mechanism of the interactions between phytochemical substances and eIF4E, molecular docking and dynamics studies were conducted. Molecular docking studies found Sizofiran (- 12.513 kcal/mol) has the most affinity eIF4E binding energy out of 93 phytochemicals, 5 current drugs, and 4 known inhibitors. This positions it as a top eIF4E inhibitor candidate. An alignment of eIF4E protein sequences from multiple pathogens revealed that the glutamate103 interacting residues are evolutionarily conserved across the different eIF4E proteins. Further insights from 100 ns of MD simulations supported Sizofiran having superior stability and eIF4E inhibition compared to reference compounds. Designed Sizofiran-related compounds showed better activity than the current drugs such as Camptosar, Sorafenib, Regorafenib, Doxorubicin, and Kenpaullone, indicating strong potential to suppress CRC progression by targeting eIF4E. This research aims to significantly aid development of improved eIF4E-targeting drugs for cancer treatment. Graphical abstract Showing the Graphical abstract of the complete study. Supplementary Information The online version contains supplementary material available at 10.1007/s40203-024-00206-3.
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Affiliation(s)
- Gopinath Samykannu
- Data Mining and Text Mining Laboratory, Department of Bioinformatics, Bharathiar University, Coimbatore, TamilNadu India
| | - Nandhini Mariyappan
- Molecular Modelling and Designing Laboratory, Department of Physics, Bharathiar University, Coimbatore, TamilNadu India
| | - Jeyakumar Natarajan
- Data Mining and Text Mining Laboratory, Department of Bioinformatics, Bharathiar University, Coimbatore, TamilNadu India
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3
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Nagaraj S, Stankiewicz-Drogon A, Darzynkiewicz E, Wojda U, Grzela R. miR-483-5p orchestrates the initiation of protein synthesis by facilitating the decrease in phosphorylated Ser209eIF4E and 4E-BP1 levels. Sci Rep 2024; 14:4237. [PMID: 38378793 PMCID: PMC10879198 DOI: 10.1038/s41598-024-54154-1] [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: 05/23/2023] [Accepted: 02/09/2024] [Indexed: 02/22/2024] Open
Abstract
Eukaryotic initiation factor 4E (eIF4E) is a pivotal protein involved in the regulatory mechanism for global protein synthesis in both physiological and pathological conditions. MicroRNAs (miRNAs) play a significant role in regulating gene expression by targeting mRNA. However, the ability of miRNAs to regulate eIF4E and its phosphorylation remains relatively unknown. In this study, we predicted and experimentally verified targets for miR-483-5p, including eukaryotic translation initiation factor eIF4E and its binding proteins, 4E-BPs, that regulate protein synthesis. Using the Web of Science database, we identified 28 experimentally verified miR-483-5p targets, and by the TargetScan database, we found 1818 predicted mRNA targets, including EIF4E, EIF4EBP1, and EIF4EBP2. We verified that miR-483-5p significantly reduced ERK1 and MKNK1 mRNA levels in HEK293 cells. Furthermore, we discovered that miR-483-5p suppressed EIF4EBP1 and EIF4EBP2, but not EIF4E. Finally, we found that miR-483-5p reduced the level of phosphorylated eIF4E (pSer209eIF4E) but not total eIF4E. In conclusion, our study suggests that miR-483-5p's multi-targeting effect on the ERK1/ MKNK1 axis modulates the phosphorylation state of eIF4E. Unlike siRNA, miRNA can have multiple targets in the pathway, and thereby exploring the role of miR-483-5p in various cancer models may uncover therapeutic options.
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Affiliation(s)
- Siranjeevi Nagaraj
- Interdisciplinary Laboratory of Molecular Biology and Biophysics, Centre of New Technologies, University of Warsaw, 02-097, Warsaw, Poland
- Laboratory of Preclinical Testing of Higher Standard, Nencki Institute of Experimental Biology of Polish Academy of Sciences, Pasteur 3, 02-093, Warsaw, Poland
| | - Anna Stankiewicz-Drogon
- Division of Biophysics, Institute of Experimental Physics, Faculty of Physics, University of Warsaw, Pasteura 5, 02-093, Warsaw, Poland
| | - Edward Darzynkiewicz
- Interdisciplinary Laboratory of Molecular Biology and Biophysics, Centre of New Technologies, University of Warsaw, 02-097, Warsaw, Poland
- Division of Biophysics, Institute of Experimental Physics, Faculty of Physics, University of Warsaw, Pasteura 5, 02-093, Warsaw, Poland
| | - Urszula Wojda
- Laboratory of Preclinical Testing of Higher Standard, Nencki Institute of Experimental Biology of Polish Academy of Sciences, Pasteur 3, 02-093, Warsaw, Poland.
| | - Renata Grzela
- Interdisciplinary Laboratory of Molecular Biology and Biophysics, Centre of New Technologies, University of Warsaw, 02-097, Warsaw, Poland.
- Division of Biophysics, Institute of Experimental Physics, Faculty of Physics, University of Warsaw, Pasteura 5, 02-093, Warsaw, Poland.
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4
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Sherwood DR, Kenny-Ganzert IW, Balachandar Thendral S. Translational regulation of cell invasion through extracellular matrix-an emerging role for ribosomes. F1000Res 2023; 12:1528. [PMID: 38628976 PMCID: PMC11019292 DOI: 10.12688/f1000research.143519.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 11/22/2023] [Indexed: 04/19/2024] Open
Abstract
Many developmental and physiological processes require cells to invade and migrate through extracellular matrix barriers. This specialized cellular behavior is also misregulated in many diseases, such as immune disorders and cancer. Cell invasive activity is driven by pro-invasive transcriptional networks that activate the expression of genes encoding numerous different proteins that expand and regulate the cytoskeleton, endomembrane system, cell adhesion, signaling pathways, and metabolic networks. While detailed mechanistic studies have uncovered crucial insights into pro-invasive transcriptional networks and the distinct cell biological attributes of invasive cells, less is known about how invasive cells modulate mRNA translation to meet the robust, dynamic, and unique protein production needs of cell invasion. In this review we outline known modes of translation regulation promoting cell invasion and focus on recent studies revealing elegant mechanisms that expand ribosome biogenesis within invasive cells to meet the increased protein production requirements to invade and migrate through extracellular matrix barriers.
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McCracken NA, Liu H, Runnebohm AM, Wijeratne HRS, Wijeratne AB, Staschke KA, Mosley AL. Obtaining Functional Proteomics Insights From Thermal Proteome Profiling Through Optimized Melt Shift Calculation and Statistical Analysis With InflectSSP. Mol Cell Proteomics 2023; 22:100630. [PMID: 37562535 PMCID: PMC10494267 DOI: 10.1016/j.mcpro.2023.100630] [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: 12/31/2022] [Revised: 07/20/2023] [Accepted: 08/03/2023] [Indexed: 08/12/2023] Open
Abstract
Thermal proteome profiling (TPP) is an invaluable tool for functional proteomics studies that has been shown to discover changes associated with protein-ligand, protein-protein, and protein-RNA interaction dynamics along with changes in protein stability resulting from cellular signaling. The increasing number of reports employing this assay has not been met concomitantly with new approaches leading to advancements in the quality and sensitivity of the corresponding data analysis. The gap between data acquisition and data analysis tools is important to fill as TPP findings have reported subtle melt shift changes related to signaling events such as protein posttranslational modifications. In this study, we have improved the Inflect data analysis pipeline (now referred to as InflectSSP, available at https://CRAN.R-project.org/package=InflectSSP) to increase the sensitivity of detection for both large and subtle changes in the proteome as measured by TPP. Specifically, InflectSSP now has integrated statistical and bioinformatic functions to improve objective functional proteomics findings from the quantitative results obtained from TPP studies through increasing both the sensitivity and specificity of the data analysis pipeline. InflectSSP incorporates calculation of a "melt coefficient" into the pipeline with production of average melt curves for biological replicate studies to aid in identification of proteins with significant melts. To benchmark InflectSSP, we have reanalyzed two previously reported datasets to demonstrate the performance of our publicly available R-based program for TPP data analysis. We report new findings following temporal treatment of human cells with the small molecule thapsigargin that induces the unfolded protein response as a consequence of inhibition of sarcoplasmic/endoplasmic reticulum calcium ATPase 2A. InflectSSP analysis of our unfolded protein response study revealed highly reproducible and statistically significant target engagement over a time course of treatment while simultaneously providing new insights into the possible mechanisms of action of the small molecule thapsigargin.
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Affiliation(s)
- Neil A McCracken
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana, United States
| | - Hao Liu
- Biostatistics and Health Data Science, Indiana University School of Medicine, Indianapolis, Indiana, United States; Department of Biostatistics and Epidemiology, Rutgers School of Public Health, Piscataway, New Jersey, United States
| | - Avery M Runnebohm
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana, United States
| | - H R Sagara Wijeratne
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana, United States
| | - Aruna B Wijeratne
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana, United States
| | - Kirk A Staschke
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana, United States
| | - Amber L Mosley
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana, United States; Center for Computational Biology and Bioinformatics, Indiana University School of Medicine, Indianapolis, Indiana, USA.
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6
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Chen X, An Y, Tan M, Xie D, Liu L, Xu B. Biological functions and research progress of eIF4E. Front Oncol 2023; 13:1076855. [PMID: 37601696 PMCID: PMC10435865 DOI: 10.3389/fonc.2023.1076855] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Accepted: 01/30/2023] [Indexed: 08/22/2023] Open
Abstract
The eukaryotic translation initiation factor eIF4E can specifically bind to the cap structure of an mRNA 5' end, mainly regulating translation initiation and preferentially enhancing the translation of carcinogenesis related mRNAs. The expression of eIF4E is closely related to a variety of malignant tumors. In tumor cells, eIF4E activity is abnormally increased, which stimulates cell growth, metastasis and translation of related proteins. The main factors affecting eIF4E activity include intranuclear regulation, phosphorylation of 4EBPs, and phosphorylation and sumoylation of eIF4E. In this review, we summarize the biological functions and the research progress of eIF4E, the main influencing factors of eIF4E activity, and the recent progress of drugs targeting eIF4E, in the hope of providing new insights for the treatment of multiple malignancies and development of targeted drugs.
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Affiliation(s)
- Xiaocong Chen
- Department of Clinical Medicine, Fenyang College of Shanxi Medical University, Fenyang, China
| | - Yang An
- Department of Clinical Medicine, Fenyang College of Shanxi Medical University, Fenyang, China
| | - Mengsi Tan
- Department of Clinical Medicine, Fenyang College of Shanxi Medical University, Fenyang, China
| | - Dongrui Xie
- Department of Clinical Medicine, Fenyang College of Shanxi Medical University, Fenyang, China
| | - Ling Liu
- Department of Medical Laboratory Science, Fenyang College of Shanxi Medical University, Fenyang, China
- Key Laboratory of Lvliang for Clinical Molecular Diagnostics, Fenyang, China
- Department of Clinical Laboratory, Fenyang Hospital of Shanxi Province, Fenyang, China
| | - Benjin Xu
- Department of Medical Laboratory Science, Fenyang College of Shanxi Medical University, Fenyang, China
- Key Laboratory of Lvliang for Clinical Molecular Diagnostics, Fenyang, China
- Department of Clinical Laboratory, Fenyang Hospital of Shanxi Province, Fenyang, China
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7
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Leibowitz BJ, Zhao G, Xia W, Wang Y, Ruan H, Zhang L, Yu J. mTOR inhibition suppresses Myc-driven polyposis by inducing immunogenic cell death. Oncogene 2023:10.1038/s41388-023-02706-6. [PMID: 37138032 DOI: 10.1038/s41388-023-02706-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Revised: 04/17/2023] [Accepted: 04/21/2023] [Indexed: 05/05/2023]
Abstract
Myc is a key driver of colorectal cancer initiation and progression, but remains a difficult drug target. In this study, we show that mTOR inhibition potently suppresses intestinal polyp formation, regresses established polyps, and prolongs lifespan of APCMin/+ mice. Everolimus in diet strongly reduces p-4EBP1, p-S6, and Myc levels, and induces apoptosis of cells with activated β-catenin (p-S552) in the polyps on day 3. The cell death is accompanied by ER stress, activation of the extrinsic apoptotic pathway, innate immune cell recruitment, and followed by T-cell infiltration on day 14 persisting for months thereafter. These effects are absent in normal intestinal crypts with physiologic levels of Myc and a high rate of proliferation. Using normal human colonic epithelial cells, EIF4E S209A knockin and BID knockout mice, we found that local inflammation and antitumor efficacy of Everolimus requires Myc-dependent induction of ER stress and apoptosis. These findings demonstrate mTOR and deregulated Myc as a selective vulnerability of mutant APC-driven intestinal tumorigenesis, whose inhibition disrupts metabolic and immune adaptation and reactivates immune surveillance necessary for long-term tumor control.
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Affiliation(s)
- Brian J Leibowitz
- Department of Pathology, University of Pittsburgh School of Medicine, UPMC Hillman Cancer Center, Pittsburgh, PA, 15213, USA
- Department of Radiation Oncology, University of Pittsburgh School of Medicine, UPMC Hillman Cancer Center, Pittsburgh, PA, 15213, USA
| | - Guangyi Zhao
- Department of Pathology, University of Pittsburgh School of Medicine, UPMC Hillman Cancer Center, Pittsburgh, PA, 15213, USA
| | - Wenxin Xia
- Department of Pathology, University of Pittsburgh School of Medicine, UPMC Hillman Cancer Center, Pittsburgh, PA, 15213, USA
- Department of Biochemistry and Molecular Pharmacology at New York University Grossman School of Medicine, New York, NY, 10016, USA
| | - Yuhan Wang
- Department of Pathology, University of Pittsburgh School of Medicine, UPMC Hillman Cancer Center, Pittsburgh, PA, 15213, USA
- Department of Medicine, University of Southern California, Keck School of Medicine, Los Angeles, CA, 90033, USA
| | - Hang Ruan
- Department of Pathology, University of Pittsburgh School of Medicine, UPMC Hillman Cancer Center, Pittsburgh, PA, 15213, USA
| | - Lin Zhang
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, UPMC Hillman Cancer Center, Pittsburgh, PA, 15213, USA
- Department of Medicine, University of Southern California, Keck School of Medicine, Los Angeles, CA, 90033, USA
| | - Jian Yu
- Department of Pathology, University of Pittsburgh School of Medicine, UPMC Hillman Cancer Center, Pittsburgh, PA, 15213, USA.
- Department of Radiation Oncology, University of Pittsburgh School of Medicine, UPMC Hillman Cancer Center, Pittsburgh, PA, 15213, USA.
- Department of Medicine, University of Southern California, Keck School of Medicine, Los Angeles, CA, 90033, USA.
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8
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Saeed H, Leibowitz BJ, Zhang L, Yu J. Targeting Myc-driven stress addiction in colorectal cancer. Drug Resist Updat 2023; 69:100963. [PMID: 37119690 DOI: 10.1016/j.drup.2023.100963] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 04/06/2023] [Accepted: 04/17/2023] [Indexed: 05/01/2023]
Abstract
MYC is a proto-oncogene that encodes a powerful regulator of transcription and cellular programs essential for normal development, as well as the growth and survival of various types of cancer cells. MYC rearrangement and amplification is a common cause of hematologic malignancies. In epithelial cancers such as colorectal cancer, genetic alterations in MYC are rare. Activation of Wnt, ERK/MAPK, and PI3K/mTOR pathways dramatically increases Myc levels through enhanced transcription, translation, and protein stability. Elevated Myc promotes stress adaptation, metabolic reprogramming, and immune evasion to drive cancer development and therapeutic resistance through broad changes in transcriptional and translational landscapes. Despite intense interest and effort, Myc remains a difficult drug target. Deregulation of Myc and its targets has profound effects that vary depending on the type of cancer and the context. Here, we summarize recent advances in the mechanistic understanding of Myc-driven oncogenesis centered around mRNA translation and proteostress. Promising strategies and agents under development to target Myc are also discussed with a focus on colorectal cancer.
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Affiliation(s)
- Haris Saeed
- UPMC Hillman Cancer Center, University of Pittsburgh School of Medicine, 5117 Centre Ave., Pittsburgh, PA 15213, USA; Dept. of Pathology, University of Pittsburgh School of Medicine, 5117 Centre Ave., Pittsburgh, PA 15213, USA
| | - Brian J Leibowitz
- UPMC Hillman Cancer Center, University of Pittsburgh School of Medicine, 5117 Centre Ave., Pittsburgh, PA 15213, USA; Dept. of Pathology, University of Pittsburgh School of Medicine, 5117 Centre Ave., Pittsburgh, PA 15213, USA
| | - Lin Zhang
- UPMC Hillman Cancer Center, University of Pittsburgh School of Medicine, 5117 Centre Ave., Pittsburgh, PA 15213, USA; Dept. of Chemical Biology and Pharmacology, University of Pittsburgh School of Medicine, 5117 Centre Ave., Pittsburgh, PA 15213, USA
| | - Jian Yu
- UPMC Hillman Cancer Center, University of Pittsburgh School of Medicine, 5117 Centre Ave., Pittsburgh, PA 15213, USA; Dept. of Pathology, University of Pittsburgh School of Medicine, 5117 Centre Ave., Pittsburgh, PA 15213, USA; Dept. of Radiation Oncology, University of Pittsburgh School of Medicine, 5117 Centre Ave., Pittsburgh, PA 15213, USA.
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9
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Dong HJ, Wang J, Zhang XZ, Li CC, Liu JF, Wang XJ. Proteomic screening identifies RPLp2 as a specific regulator for the translation of coronavirus. Int J Biol Macromol 2023; 230:123191. [PMID: 36632964 PMCID: PMC9827737 DOI: 10.1016/j.ijbiomac.2023.123191] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2022] [Revised: 01/03/2023] [Accepted: 01/04/2023] [Indexed: 01/11/2023]
Abstract
Viral mRNA of coronavirus translates in an eIF4E-dependent manner, and the phosphorylation of eIF4E can modulate this process, but the role of p-eIF4E in coronavirus infection is not yet entirely evident. p-eIF4E favors the translation of selected mRNAs, specifically the mRNAs that encode proteins associated with cell proliferation, inflammation, the extracellular matrix, and tumor formation and metastasis. In the present work, two rounds of TMT relative quantitative proteomics were used to screen 77 cellular factors that are upregulated upon infection by coronavirus PEDV and are potentially susceptible to a high level of p-eIF4E. PEDV infection increased the translation level of ribosomal protein lateral stalk subunit RPLp2 (but not subunit RPLp0/1) in a p-eIF4E-dependent manner. The bicistronic dual-reporter assay and polysome profile showed that RPLp2 is essential for translating the viral mRNA of PEDV. RNA binding protein and immunoprecipitation assay showed that RPLp2 interacted with PEDV 5'UTR via association with eIF4E. Moreover, the cap pull-down assay showed that the viral nucleocapsid protein is recruited in m7GTP-precipitated complexes with the assistance of RPLp2. The heterogeneous ribosomes, which are different in composition, regulate the selective translation of specific mRNAs. Our study proves that viral mRNA and protein utilize translation factors and heterogeneous ribosomes for preferential translation initiation. This previously uncharacterized process may be involved in the selective translation of coronavirus.
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Affiliation(s)
- Hui-Jun Dong
- Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
| | - Jing Wang
- Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
| | - Xiu-Zhong Zhang
- Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
| | - Cui-Cui Li
- Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
| | - Jian-Feng Liu
- College of Animal Science and Technol, China Agricultural University, Beijing 100193, China.
| | - Xiao-Jia Wang
- Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China.
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10
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Therapeutic targeting of eukaryotic initiation factor (eIF) 4E. Biochem Soc Trans 2023; 51:113-124. [PMID: 36661272 DOI: 10.1042/bst20220285] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Revised: 01/06/2023] [Accepted: 01/10/2023] [Indexed: 01/21/2023]
Abstract
Fundamental studies unraveled the role of eukaryotic initiation factor (eIF) 4E in mRNA translation and its control. Under physiological conditions, regulation of translation by eIF4E is essential to cellular homeostasis. Under stress, gene flow information is parsed by eIF4E to support adaptive mechanisms that favor cell survival. Dysregulated eIF4E activity fuels tumor formation and progression and modulates response to therapy. Thus, there has been heightened interest in understanding eIF4E function in controlling gene expression as well as developing strategies to block its activity to treat disease.
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11
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Manne BK, Campbell RA, Bhatlekar S, Ajanel A, Denorme F, Portier I, Middleton EA, Tolley ND, Kosaka Y, Montenont E, Guo L, Rowley JW, Bray PF, Jacob S, Fukanaga R, Proud C, Weyrich AS, Rondina MT. MAPK-interacting kinase 1 regulates platelet production, activation, and thrombosis. Blood 2022; 140:2477-2489. [PMID: 35930749 PMCID: PMC9918849 DOI: 10.1182/blood.2022015568] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Revised: 07/06/2022] [Accepted: 07/20/2022] [Indexed: 12/13/2022] Open
Abstract
The MAPK-interacting kinase (Mnk) family includes Mnk1 and Mnk2, which are phosphorylated and activated in response to extracellular stimuli. Mnk1 contributes to cellular responses by regulating messenger RNA (mRNA) translation, and mRNA translation influences platelet production and function. However, the role of Mnk1 in megakaryocytes and platelets has not previously been studied. The present study investigated Mnk1 in megakaryocytes and platelets using both pharmacological and genetic approaches. We demonstrate that Mnk1, but not Mnk2, is expressed and active in human and murine megakaryocytes and platelets. Stimulating human and murine megakaryocytes and platelets induced Mnk1 activation and phosphorylation of eIF4E, a downstream target of activated Mnk1 that triggers mRNA translation. Mnk1 inhibition or deletion significantly diminished protein synthesis in megakaryocytes as measured by polysome profiling and [35S]-methionine incorporation assays. Depletion of Mnk1 also reduced megakaryocyte ploidy and proplatelet forming megakaryocytes in vitro and resulted in thrombocytopenia. However, Mnk1 deletion did not affect the half-life of circulating platelets. Platelets from Mnk1 knockout mice exhibited reduced platelet aggregation, α granule secretion, and integrin αIIbβ3 activation. Ribosomal footprint sequencing indicated that Mnk1 regulates the translation of Pla2g4a mRNA (which encodes cPLA2) in megakaryocytes. Consistent with this, Mnk1 ablation reduced cPLA2 activity and thromboxane generation in platelets and megakaryocytes. In vivo, Mnk1 ablation protected against platelet-dependent thromboembolism. These results provide previously unrecognized evidence that Mnk1 regulates mRNA translation and cellular activation in platelets and megakaryocytes, endomitosis and thrombopoiesis, and thrombosis.
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Affiliation(s)
| | - Robert A. Campbell
- University of Utah Molecular Medicine Program, Salt Lake City, UT
- Department of Internal Medicine, University of Utah Health, Salt Lake City, UT
- Department of Pathology, University of Utah Health, Salt Lake City, UT
| | - Seema Bhatlekar
- University of Utah Molecular Medicine Program, Salt Lake City, UT
| | - Abigail Ajanel
- University of Utah Molecular Medicine Program, Salt Lake City, UT
- Department of Pathology, University of Utah Health, Salt Lake City, UT
| | - Frederik Denorme
- University of Utah Molecular Medicine Program, Salt Lake City, UT
| | - Irina Portier
- University of Utah Molecular Medicine Program, Salt Lake City, UT
| | - Elizabeth A. Middleton
- University of Utah Molecular Medicine Program, Salt Lake City, UT
- Department of Internal Medicine, University of Utah Health, Salt Lake City, UT
| | - Neal D. Tolley
- University of Utah Molecular Medicine Program, Salt Lake City, UT
| | - Yasuhiro Kosaka
- University of Utah Molecular Medicine Program, Salt Lake City, UT
| | - Emilie Montenont
- University of Utah Molecular Medicine Program, Salt Lake City, UT
| | - Li Guo
- University of Utah Molecular Medicine Program, Salt Lake City, UT
| | - Jesse W. Rowley
- University of Utah Molecular Medicine Program, Salt Lake City, UT
- Department of Internal Medicine, University of Utah Health, Salt Lake City, UT
| | - Paul F. Bray
- University of Utah Molecular Medicine Program, Salt Lake City, UT
- Department of Internal Medicine, University of Utah Health, Salt Lake City, UT
| | - Shancy Jacob
- University of Utah Molecular Medicine Program, Salt Lake City, UT
| | - Rikiro Fukanaga
- Department of Biochemistry, Osaka University of Pharmaceutical Sciences, Osaka, Japan
| | - Christopher Proud
- Lifelong Health, South Australian Health & Medical Research Institute, Adelaide, Australia
- Department of Biological Sciences, University of Adelaide, Adelaide, Australia
| | - Andrew S. Weyrich
- University of Utah Molecular Medicine Program, Salt Lake City, UT
- Department of Internal Medicine, University of Utah Health, Salt Lake City, UT
| | - Matthew T. Rondina
- University of Utah Molecular Medicine Program, Salt Lake City, UT
- Department of Internal Medicine, University of Utah Health, Salt Lake City, UT
- Department of Pathology, University of Utah Health, Salt Lake City, UT
- Department of Internal Medicine and the Geriatric Research, Education, and Clinical Center (GRECC), George E. Wahlen Veterans Affairs Medical Center (VAMC), Salt Lake City, UT
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12
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Ha DP, Huang B, Wang H, Rangel DF, Van Krieken R, Liu Z, Samanta S, Neamati N, Lee AS. Targeting GRP78 suppresses oncogenic KRAS protein expression and reduces viability of cancer cells bearing various KRAS mutations. Neoplasia 2022; 33:100837. [PMID: 36162331 PMCID: PMC9516447 DOI: 10.1016/j.neo.2022.100837] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 09/01/2022] [Accepted: 09/14/2022] [Indexed: 11/18/2022]
Abstract
KRAS is the most commonly mutated oncogene in human cancers with limited therapeutic options, thus there is a critical need to identify novel targets and inhibiting agents. The 78-kDa glucose-regulated protein GRP78, which is upregulated in KRAS cancers, is an essential chaperone and the master regulator of the unfolded protein response (UPR). Following up on our recent discoveries that GRP78 haploinsufficiency suppresses both KRASG12D-driven pancreatic and lung tumorigenesis, we seek to determine the underlying mechanisms. Here, we report that knockdown of GRP78 via siRNA reduced oncogenic KRAS protein level in human lung, colon, and pancreatic cancer cells bearing various KRAS mutations. This effect was at the post-transcriptional level and is independent of proteasomal degradation or autophagy. Moreover, targeting GRP78 via small molecule inhibitors such as HA15 and YUM70 with anti-cancer activities while sparing normal cells significantly suppressed oncogenic KRAS expression in vitro and in vivo, associating with onset of apoptosis and loss of viability in cancer cells bearing various KRAS mutations. Collectively, our studies reveal that GRP78 is a previously unidentified regulator of oncogenic KRAS expression, and, as such, augments the other anti-cancer activities of GRP78 small molecule inhibitors to potentially achieve general, long-term suppression of mutant KRAS-driven tumorigenesis.
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Affiliation(s)
- Dat P Ha
- Department of Biochemistry and Molecular Medicine, University of Southern California, Keck School of Medicine, Los Angeles, California, USA; USC Norris Comprehensive Cancer Center
| | - Bo Huang
- Department of Biochemistry and Molecular Medicine, University of Southern California, Keck School of Medicine, Los Angeles, California, USA; USC Norris Comprehensive Cancer Center
| | - Han Wang
- Department of Biochemistry and Molecular Medicine, University of Southern California, Keck School of Medicine, Los Angeles, California, USA; USC Norris Comprehensive Cancer Center
| | - Daisy Flores Rangel
- Department of Biochemistry and Molecular Medicine, University of Southern California, Keck School of Medicine, Los Angeles, California, USA; USC Norris Comprehensive Cancer Center
| | - Richard Van Krieken
- Department of Biochemistry and Molecular Medicine, University of Southern California, Keck School of Medicine, Los Angeles, California, USA; USC Norris Comprehensive Cancer Center
| | - Ze Liu
- Department of Biochemistry and Molecular Medicine, University of Southern California, Keck School of Medicine, Los Angeles, California, USA; USC Norris Comprehensive Cancer Center
| | - Soma Samanta
- Department of Medicinal Chemistry, College of Pharmacy, Rogel Cancer Center, University of Michigan, Ann Arbor, Michigan, USA
| | - Nouri Neamati
- Department of Medicinal Chemistry, College of Pharmacy, Rogel Cancer Center, University of Michigan, Ann Arbor, Michigan, USA
| | - Amy S Lee
- Department of Biochemistry and Molecular Medicine, University of Southern California, Keck School of Medicine, Los Angeles, California, USA; USC Norris Comprehensive Cancer Center.
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13
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A noncanonical function of EIF4E limits ALDH1B1 activity and increases susceptibility to ferroptosis. Nat Commun 2022; 13:6318. [PMID: 36274088 PMCID: PMC9588786 DOI: 10.1038/s41467-022-34096-w] [Citation(s) in RCA: 40] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Accepted: 10/13/2022] [Indexed: 12/25/2022] Open
Abstract
Ferroptosis is a type of lipid peroxidation-dependent cell death that is emerging as a therapeutic target for cancer. However, the mechanisms of ferroptosis during the generation and detoxification of lipid peroxidation products remain rather poorly defined. Here, we report an unexpected role for the eukaryotic translation initiation factor EIF4E as a determinant of ferroptotic sensitivity by controlling lipid peroxidation. A drug screening identified 4EGI-1 and 4E1RCat (previously known as EIF4E-EIF4G1 interaction inhibitors) as powerful inhibitors of ferroptosis. Genetic and functional studies showed that EIF4E (but not EIF4G1) promotes ferroptosis in a translation-independent manner. Using mass spectrometry and subsequent protein-protein interaction analysis, we identified EIF4E as an endogenous repressor of ALDH1B1 in mitochondria. ALDH1B1 belongs to the family of aldehyde dehydrogenases and may metabolize the aldehyde substrate 4-hydroxynonenal (4HNE) at high concentrations. Supraphysiological levels of 4HNE triggered ferroptosis, while low concentrations of 4HNE increased the cell susceptibility to classical ferroptosis inducers by activating the NOX1 pathway. Accordingly, EIF4E-dependent ALDH1B1 inhibition enhanced the anticancer activity of ferroptosis inducers in vitro and in vivo. Our results support a key function of EIF4E in orchestrating lipid peroxidation to ignite ferroptosis.
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14
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Muñoz-Ayala A, Chimal-Vega B, García-González V. Translation initiation and its relationship with metabolic mechanisms in cancer development, progression and chemoresistance. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2022; 132:111-141. [PMID: 36088073 DOI: 10.1016/bs.apcsb.2022.05.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Pathways that regulate protein homeostasis (proteostasis) in cells range from mRNA processing to protein degradation; perturbations in regulatory mechanisms of these pathways can lead to oncogenic cellular processes. Protein synthesis modulation failures are common phenomena in cancer cells, wherein specific conditions that promote the translation of protein factors promoting carcinogenesis are present. These specific conditions may be favored by metabolic lipid alterations like those found in metabolic syndrome and obesity. Protein translation modifications have been described in obesity, favoring the translation of protein targets that benefit lipid accumulation; a determining factor is the activity of the cap-binding eukaryotic translation initiation factor 4E (eIF4E), a crosstalk in protein translation and lipogenesis. Besides, alterations of protein translation initiation steps are critical participants for the development of both pathogenic conditions, cancer, and obesity. This chapter is focused on the regulation of recognition and processing of carcinogenic-mRNA and the connections among lipid metabolism and cell signaling pathways that promote oncogenesis, tumoral microenvironment generation and potentially the development of chemoresistance. We performed an in-depth analysis of events, such as those occurring in obesity and dyslipidemias, that may influence protein translation, driving the recognition of certain mRNAs and favoring cancer development and chemoresistance.
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Affiliation(s)
- Andrea Muñoz-Ayala
- Departamento de Bioquímica, Facultad de Medicina Mexicali, Universidad Autónoma de Baja California, Mexicali, México; Laboratorio Multidisciplinario de Estudios Metabólicos y Cáncer, Universidad Autónoma de Baja California, Mexicali, México
| | - Brenda Chimal-Vega
- Departamento de Bioquímica, Facultad de Medicina Mexicali, Universidad Autónoma de Baja California, Mexicali, México; Laboratorio Multidisciplinario de Estudios Metabólicos y Cáncer, Universidad Autónoma de Baja California, Mexicali, México
| | - Victor García-González
- Departamento de Bioquímica, Facultad de Medicina Mexicali, Universidad Autónoma de Baja California, Mexicali, México; Laboratorio Multidisciplinario de Estudios Metabólicos y Cáncer, Universidad Autónoma de Baja California, Mexicali, México.
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15
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Ruan H, Leibowitz BJ, Peng Y, Shen L, Chen L, Kuang C, Schoen RE, Lu X, Zhang L, Yu J. Targeting Myc-driven stress vulnerability in mutant KRAS colorectal cancer. MOLECULAR BIOMEDICINE 2022; 3:10. [PMID: 35307764 PMCID: PMC8934835 DOI: 10.1186/s43556-022-00070-7] [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: 09/30/2021] [Accepted: 01/21/2022] [Indexed: 12/16/2022] Open
Abstract
Mutant KRAS is a key driver in colorectal cancer (CRC) and promotes Myc translation and Myc-dependent stress adaptation and proliferation. Here, we report that the combination of two FDA-approved drugs Bortezomib and Everolimus (RAD001) (BR) is highly efficacious against mutant KRAS CRC cells. Mechanistically, the combination, not single agent, rapidly depletes Myc protein, not mRNA, and leads to GCN2- and p-eIF2α-dependent cell death through the activation of extrinsic and intrinsic apoptotic pathways. Cell death is selectively induced in mutant KRAS CRC cells with elevated basal Myc and p-eIF2α and is characterized by CHOP induction and transcriptional signatures in proteotoxicity, oxidative stress, metabolic inhibition, and immune activation. BR-induced p-GCN2/p-eIF2α elevation and cell death are strongly attenuated by MYC knockdown and enhanced by MYC overexpression. The BR combination is efficacious against mutant KRAS patient derived organoids (PDO) and xenografts (PDX) by inducing p-eIF2α/CHOP and cell death. Interestingly, an elevated four-gene (DDIT3, GADD45B, CRYBA4 and HSPA1L) stress signature is linked to shortened overall survival in CRC patients. These data support that Myc-dependent stress adaptation drives the progression of mutant KRAS CRC and serves as a therapeutic vulnerability, which can be targeted using dual translational inhibitors.
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Affiliation(s)
- Hang Ruan
- grid.412689.00000 0001 0650 7433UPMC Hillman Cancer Center Research Pavilion, Suite 2.26h, 5117 Centre Ave., Pittsburgh, PA 15213 USA ,grid.21925.3d0000 0004 1936 9000Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213 USA
| | - Brian J. Leibowitz
- grid.412689.00000 0001 0650 7433UPMC Hillman Cancer Center Research Pavilion, Suite 2.26h, 5117 Centre Ave., Pittsburgh, PA 15213 USA ,grid.21925.3d0000 0004 1936 9000Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213 USA
| | - Yingpeng Peng
- grid.412689.00000 0001 0650 7433UPMC Hillman Cancer Center Research Pavilion, Suite 2.26h, 5117 Centre Ave., Pittsburgh, PA 15213 USA ,grid.21925.3d0000 0004 1936 9000Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213 USA
| | - Lin Shen
- grid.412689.00000 0001 0650 7433UPMC Hillman Cancer Center Research Pavilion, Suite 2.26h, 5117 Centre Ave., Pittsburgh, PA 15213 USA ,grid.21925.3d0000 0004 1936 9000Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213 USA ,grid.452223.00000 0004 1757 7615Department of Oncology, Xiangya Hospital, Central South University, Changsha, Hunan 410008 P.R. China
| | - Lujia Chen
- grid.412689.00000 0001 0650 7433UPMC Hillman Cancer Center Research Pavilion, Suite 2.26h, 5117 Centre Ave., Pittsburgh, PA 15213 USA ,grid.21925.3d0000 0004 1936 9000Department of Medical Informatics, University of Pittsburgh School of Medicine, Pittsburgh, PA 15232 USA
| | - Charlie Kuang
- grid.412689.00000 0001 0650 7433UPMC Hillman Cancer Center Research Pavilion, Suite 2.26h, 5117 Centre Ave., Pittsburgh, PA 15213 USA ,grid.21925.3d0000 0004 1936 9000Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213 USA
| | - Robert E. Schoen
- grid.412689.00000 0001 0650 7433UPMC Hillman Cancer Center Research Pavilion, Suite 2.26h, 5117 Centre Ave., Pittsburgh, PA 15213 USA ,grid.21925.3d0000 0004 1936 9000Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213 USA ,grid.21925.3d0000 0004 1936 9000Department of Epidemiology, University of Pittsburgh School of Public Health Pittsburgh, Pittsburgh, PA 15213 USA
| | - Xinghua Lu
- grid.412689.00000 0001 0650 7433UPMC Hillman Cancer Center Research Pavilion, Suite 2.26h, 5117 Centre Ave., Pittsburgh, PA 15213 USA ,grid.21925.3d0000 0004 1936 9000Department of Medical Informatics, University of Pittsburgh School of Medicine, Pittsburgh, PA 15232 USA
| | - Lin Zhang
- grid.412689.00000 0001 0650 7433UPMC Hillman Cancer Center Research Pavilion, Suite 2.26h, 5117 Centre Ave., Pittsburgh, PA 15213 USA ,grid.21925.3d0000 0004 1936 9000Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213 USA
| | - Jian Yu
- grid.412689.00000 0001 0650 7433UPMC Hillman Cancer Center Research Pavilion, Suite 2.26h, 5117 Centre Ave., Pittsburgh, PA 15213 USA ,grid.21925.3d0000 0004 1936 9000Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213 USA
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16
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Control of the eIF4E activity: structural insights and pharmacological implications. Cell Mol Life Sci 2021; 78:6869-6885. [PMID: 34541613 PMCID: PMC8558276 DOI: 10.1007/s00018-021-03938-z] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 08/28/2021] [Accepted: 09/08/2021] [Indexed: 12/17/2022]
Abstract
The central role of eukaryotic translation initiation factor 4E (eIF4E) in controlling mRNA translation has been clearly assessed in the last decades. eIF4E function is essential for numerous physiological processes, such as protein synthesis, cellular growth and differentiation; dysregulation of its activity has been linked to ageing, cancer onset and progression and neurodevelopmental disorders, such as autism spectrum disorder (ASD) and Fragile X Syndrome (FXS). The interaction between eIF4E and the eukaryotic initiation factor 4G (eIF4G) is crucial for the assembly of the translational machinery, the initial step of mRNA translation. A well-characterized group of proteins, named 4E-binding proteins (4E-BPs), inhibits the eIF4E–eIF4G interaction by competing for the same binding site on the eIF4E surface. 4E-BPs and eIF4G share a single canonical motif for the interaction with a conserved hydrophobic patch of eIF4E. However, a second non-canonical and not conserved binding motif was recently detected for eIF4G and several 4E-BPs. Here, we review the structural features of the interaction between eIF4E and its molecular partners eIF4G and 4E-BPs, focusing on the implications of the recent structural and biochemical evidence for the development of new therapeutic strategies. The design of novel eIF4E-targeting molecules that inhibit translation might provide new avenues for the treatment of several conditions.
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17
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Synthetic mRNAs; Their Analogue Caps and Contribution to Disease. Diseases 2021; 9:diseases9030057. [PMID: 34449596 PMCID: PMC8395722 DOI: 10.3390/diseases9030057] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2021] [Revised: 08/11/2021] [Accepted: 08/19/2021] [Indexed: 12/22/2022] Open
Abstract
The structure of synthetic mRNAs as used in vaccination against cancer and infectious diseases contain specifically designed caps followed by sequences of the 5′ untranslated repeats of β-globin gene. The strategy for successful design of synthetic mRNAs by chemically modifying their caps aims to increase resistance to the enzymatic deccapping complex, offer a higher affinity for binding to the eukaryotic translation initiation factor 4E (elF4E) protein and enforce increased translation of their encoded proteins. However, the cellular homeostasis is finely balanced and obeys to specific laws of thermodynamics conferring balance between complexity and growth rate in evolution. An overwhelming and forced translation even under alarming conditions of the cell during a concurrent viral infection, or when molecular pathways are trying to circumvent precursor events that lead to autoimmunity and cancer, may cause the recipient cells to ignore their differential sensitivities which are essential for keeping normal conditions. The elF4E which is a powerful RNA regulon and a potent oncogene governing cell cycle progression and proliferation at a post-transcriptional level, may then be a great contributor to disease development. The mechanistic target of rapamycin (mTOR) axis manly inhibits the elF4E to proceed with mRNA translation but disturbance in fine balances between mTOR and elF4E action may provide a premature step towards oncogenesis, ignite pre-causal mechanisms of immune deregulation and cause maturation (aging) defects.
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18
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Gen Y, Muramatsu T, Inoue J, Inazawa J. miR-766-5p targets super-enhancers by downregulating CBP and BRD4. Cancer Res 2021; 81:5190-5201. [PMID: 34353856 DOI: 10.1158/0008-5472.can-21-0649] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Revised: 06/29/2021] [Accepted: 07/28/2021] [Indexed: 11/16/2022]
Abstract
Super-enhancers (SE) are clusters of transcription enhancers that drive gene expression. SEs are typically characterized by high levels of acetylation of histone H3 lysine 27 (H3K27ac), which is catalyzed by the histone lysine acetyltransferase CREB binding protein (CBP). Cancer cells frequently acquire tumor-specific SEs at key oncogenes, such as MYC, which induce several hallmarks of cancer. BRD4 is recruited to SEs and consequently functions as an epigenetic reader to promote transcription of SE-marked genes in cancer cells. miRNAs can be potent candidates for nucleic acid therapeutics for cancer. We previously identified miR-766-5p as a miRNA that downregulated MYC expression and inhibited cancer cell growth in vitro. In this study, we show that miR-766-5p directly targets CBP and BRD4. Concurrent suppression of CBP and BRD4 cooperatively downregulated MYC expression in cancer cells but not in normal cells. Chromatin immunoprecipitation analysis revealed that miR-766-5p reduced levels of H3K27ac at MYC SEs via CBP suppression. Moreover, miR-766-5p suppressed expression of a BRD4-NUT fusion protein that drives NUT midline carcinoma (NMC). In vivo administration of miR-766-5p suppressed tumor growth in two xenograft models. Collectively, these data suggest that targeting SEs using miR-766-5p-based therapeutics may serve as an effective strategy for the treatment of MYC-driven cancers.
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Affiliation(s)
- Yasuyuki Gen
- Department of Molecular Cytogenetics, Tokyo Medical and Dental University
| | - Tomoki Muramatsu
- Molecular Cytogenetics, Medical Research Institute, Tokyo Medical and Dental University
| | - Jun Inoue
- Department of Molecular Cytogenetics, Medical Research Institute and Graduate School of Medical and Dental Science, Tokyo Medical and Dental University
| | - Johji Inazawa
- Department of Molecular Cytogenetics, Medical Research Institute, Tokyo Medical and Dental University (TMDU)
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19
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Jana S, Deo R, Hough RP, Liu Y, Horn JL, Wright JL, Lam HM, Webster KR, Chiang GG, Sonenberg N, Hsieh AC. mRNA translation is a therapeutic vulnerability necessary for bladder epithelial transformation. JCI Insight 2021; 6:e144920. [PMID: 34032633 PMCID: PMC8262354 DOI: 10.1172/jci.insight.144920] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Accepted: 04/29/2021] [Indexed: 12/22/2022] Open
Abstract
Using genetically engineered mouse models, this work demonstrates that protein synthesis is essential for efficient urothelial cancer formation and growth but dispensable for bladder homeostasis. Through a candidate gene analysis for translation regulators implicated in this dependency, we discovered that phosphorylation of the translation initiation factor eIF4E at serine 209 is increased in both murine and human bladder cancer, and this phosphorylation corresponds with an increase in de novo protein synthesis. Employing an eIF4E serine 209 to alanine knock-in mutant mouse model, we show that this single posttranslational modification is critical for bladder cancer initiation and progression, despite having no impact on normal bladder tissue maintenance. Using murine and human models of advanced bladder cancer, we demonstrate that only tumors with high levels of eIF4E phosphorylation are therapeutically vulnerable to eFT508, the first clinical-grade inhibitor of MNK1 and MNK2, the upstream kinases of eIF4E. Our results show that phospho-eIF4E plays an important role in bladder cancer pathogenesis, and targeting its upstream kinases could be an effective therapeutic option for bladder cancer patients with high levels of eIF4E phosphorylation.
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Affiliation(s)
- Sujata Jana
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - Rucha Deo
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - Rowan P Hough
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - Yuzhen Liu
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - Jessie L Horn
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - Jonathan L Wright
- Department of Urology, University of Washington, Seattle, Washington, USA
| | - Hung-Ming Lam
- Department of Urology, University of Washington, Seattle, Washington, USA
| | - Kevin R Webster
- Cancer Biology, eFFECTOR Therapeutics, San Diego, California, USA
| | - Gary G Chiang
- Cancer Biology, eFFECTOR Therapeutics, San Diego, California, USA
| | - Nahum Sonenberg
- Department of Biochemistry, McGill University, Montreal, Quebec, Canada
| | - Andrew C Hsieh
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA.,University of Washington Departments of Medicine and Genome Sciences, Seattle, Washington, USA
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20
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Knight JRP, Sansom OJ. Tuning protein synthesis for cancer therapy. Mol Cell Oncol 2021; 8:1884034. [PMID: 33855169 PMCID: PMC8018481 DOI: 10.1080/23723556.2021.1884034] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 01/26/2021] [Accepted: 01/27/2021] [Indexed: 11/02/2022]
Abstract
~50% of colorectal cancers have an activating mutation in KRAS (encoding the KRAS proto-oncogene) and remain difficult to target in the clinic. We have recently shown that activation of KRAS protein alters the regulation of mRNA translation, increasing total protein synthesis, and maintaining elevated c-MYC (MYC proto-oncogene) expression. Targeting these pathways downstream of KRAS reveals a striking dependency that has potential for clinical translation.
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Affiliation(s)
| | - Owen J. Sansom
- CRUK Beatson Institute, University of Glasgow, Glasgow, UK
- Institute of Cancer Sciences, University of Glasgow, UK
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