1
|
Mahé M, Rios-Fuller T, Katsara O, Schneider RJ. Non-canonical mRNA translation initiation in cell stress and cancer. NAR Cancer 2024; 6:zcae026. [PMID: 38828390 PMCID: PMC11140632 DOI: 10.1093/narcan/zcae026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Revised: 05/08/2024] [Accepted: 05/29/2024] [Indexed: 06/05/2024] Open
Abstract
The now well described canonical mRNA translation initiation mechanism of m7G 'cap' recognition by cap-binding protein eIF4E and assembly of the canonical pre-initiation complex consisting of scaffolding protein eIF4G and RNA helicase eIF4A has historically been thought to describe all cellular mRNA translation. However, the past decade has seen the discovery of alternative mechanisms to canonical eIF4E mediated mRNA translation initiation. Studies have shown that non-canonical alternate mechanisms of cellular mRNA translation initiation, whether cap-dependent or independent, serve to provide selective translation of mRNAs under cell physiological and pathological stress conditions. These conditions typically involve the global downregulation of canonical eIF4E1/cap-mediated mRNA translation, and selective translational reprogramming of the cell proteome, as occurs in tumor development and malignant progression. Cancer cells must be able to maintain physiological plasticity to acquire a migratory phenotype, invade tissues, metastasize, survive and adapt to severe microenvironmental stress conditions that involve inhibition of canonical mRNA translation initiation. In this review we describe the emerging, important role of non-canonical, alternate mechanisms of mRNA translation initiation in cancer, particularly in adaptation to stresses and the phenotypic cell fate changes involved in malignant progression and metastasis. These alternate translation initiation mechanisms provide new targets for oncology therapeutics development.
Collapse
Affiliation(s)
- Mélanie Mahé
- Department of Microbiology, NYU Grossman School of Medicine, New York, NY 10016, USA
| | - Tiffany Rios-Fuller
- Department of Microbiology, NYU Grossman School of Medicine, New York, NY 10016, USA
| | - Olga Katsara
- Department of Microbiology, NYU Grossman School of Medicine, New York, NY 10016, USA
| | - Robert J Schneider
- Department of Microbiology, NYU Grossman School of Medicine, New York, NY 10016, USA
| |
Collapse
|
2
|
Song CY, Hsieh SL, Yang SY, Lin CY, Wang SW, Tsai CH, Lo YS, Fong YC, Tang CH. Visfatin Facilitates VEGF-D-Induced Lymphangiogenesis through Activating HIF-1α and Suppressing miR-2277-3p in Human Chondrosarcoma. Int J Mol Sci 2024; 25:5142. [PMID: 38791180 PMCID: PMC11121249 DOI: 10.3390/ijms25105142] [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: 04/02/2024] [Revised: 05/07/2024] [Accepted: 05/08/2024] [Indexed: 05/26/2024] Open
Abstract
Chondrosarcoma is a malignant bone tumor that arises from abnormalities in cartilaginous tissue and is associated with lung metastases. Lymphangiogenesis plays an essential role in cancer metastasis. Visfatin is an adipokine reported to enhance tumor metastasis, but its relationship with VEGF-D generation and lymphangiogenesis in chondrosarcoma remains undetermined. Our results from clinical samples reveal that VEGF-D levels are markedly higher in chondrosarcoma patients than in normal individuals. Visfatin stimulation promotes VEGF-D-dependent lymphatic endothelial cell lymphangiogenesis. We also found that visfatin induces VEGF-D production by activating HIF-1α and reducing miR-2277-3p generation through the Raf/MEK/ERK signaling cascade. Importantly, visfatin controls chondrosarcoma-related lymphangiogenesis in vivo. Therefore, visfatin is a promising target in the treatment of chondrosarcoma lymphangiogenesis.
Collapse
Affiliation(s)
- Chang-Yu Song
- Graduate Institute of Biomedical Science, China Medical University, Taichung 40402, Taiwan; (C.-Y.S.); (S.-L.H.)
| | - Shang-Lin Hsieh
- Graduate Institute of Biomedical Science, China Medical University, Taichung 40402, Taiwan; (C.-Y.S.); (S.-L.H.)
- Minimally Invasive Spine and Joint Center, Buddhist Tzu Chi General Hospital Taichung Branch, Taichung 42721, Taiwan
| | - Shang-Yu Yang
- Department of Medical Laboratory Science and Biotechnology, Asia University, Taichung 41354, Taiwan;
| | - Chih-Yang Lin
- Translational Medicine Center, Shin-Kong Wu Ho-Su Memorial Hospital, Taipei 11104, Taiwan;
| | - Shih-Wei Wang
- Institute of Biomedical Sciences, Mackay Medical College, New Taipei City 25245, Taiwan;
- Department of Medicine, Mackay Medical College, New Taipei City 25245, Taiwan
| | - Chun-Hao Tsai
- Department of Sports Medicine, College of Health Care, China Medical University, Taichung 40432, Taiwan; (C.-H.T.); (Y.-C.F.)
- Department of Orthopedic Surgery, China Medical University Hospital, Taichung 40432, Taiwan;
| | - Yuan-Shun Lo
- Department of Orthopedic Surgery, China Medical University Hospital, Taichung 40432, Taiwan;
- Department of Orthopedic Surgery, China Medical University Beigang Hospital, Yunlin 65101, Taiwan
- Graduate Institute of Precision Engineering, National Chung Hsing University, Taichung 40227, Taiwan
| | - Yi-Chin Fong
- Department of Sports Medicine, College of Health Care, China Medical University, Taichung 40432, Taiwan; (C.-H.T.); (Y.-C.F.)
- Department of Orthopedic Surgery, China Medical University Hospital, Taichung 40432, Taiwan;
- Department of Orthopedic Surgery, China Medical University Beigang Hospital, Yunlin 65101, Taiwan
| | - Chih-Hsin Tang
- Graduate Institute of Biomedical Science, China Medical University, Taichung 40402, Taiwan; (C.-Y.S.); (S.-L.H.)
- Department of Medical Laboratory Science and Biotechnology, Asia University, Taichung 41354, Taiwan;
- Department of Pharmacology, School of Medicine, China Medical University, Taichung 40402, Taiwan
- Chinese Medicine Research Center, China Medical University, Taichung 40402, Taiwan
- Department of Medical Research, China Medical University Hsinchu Hospital, Hsinchu 30205, Taiwan
| |
Collapse
|
3
|
Fang J, Orobator ON, Olelewe C, Passeri G, Singh K, Awuah SG, Suntharalingam K. A Breast Cancer Stem Active Cobalt(III)-Cyclam Complex Containing Flufenamic Acid with Immunogenic Potential. Angew Chem Int Ed Engl 2024; 63:e202317940. [PMID: 38063406 PMCID: PMC10952489 DOI: 10.1002/anie.202317940] [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: 11/23/2023] [Indexed: 12/31/2023]
Abstract
The cytotoxic and immunogenic-activating properties of a cobalt(III)-cyclam complex bearing the non-steroidal anti-inflammatory drug, flufenamic acid is reported within the context of anti-cancer stem cell (CSC) drug discovery. The cobalt(III)-cyclam complex 1 displays sub-micromolar potency towards breast CSCs grown in monolayers, 24-fold and 31-fold greater than salinomycin (an established anti-breast CSC agent) and cisplatin (an anticancer metallopharmaceutical), respectively. Strikingly, the cobalt(III)-cyclam complex 1 is 69-fold and 50-fold more potent than salinomycin and cisplatin towards three-dimensionally cultured breast CSC mammospheres. Mechanistic studies reveal that 1 induces DNA damage, inhibits cyclooxygenase-2 expression, and prompts caspase-dependent apoptosis. Breast CSCs treated with 1 exhibit damage-associated molecular patterns characteristic of immunogenic cell death and are phagocytosed by macrophages. As far as we are aware, 1 is the first cobalt complex of any oxidation state or geometry to display both cytotoxic and immunogenic-activating effects on breast CSCs.
Collapse
Affiliation(s)
- Jiaxin Fang
- School of ChemistryUniversity of LeicesterLeicesterUK
| | | | | | | | - Kuldip Singh
- School of ChemistryUniversity of LeicesterLeicesterUK
| | - Samuel G. Awuah
- Department of ChemistryUniversity of KentuckyLexingtonKYUSA
- Department of Pharmaceutical SciencesUniversity of KentuckyLexingtonKYUSA
| | | |
Collapse
|
4
|
Hernández G, Vazquez-Pianzola P. eIF4E as a molecular wildcard in metazoans RNA metabolism. Biol Rev Camb Philos Soc 2023; 98:2284-2306. [PMID: 37553111 DOI: 10.1111/brv.13005] [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: 02/09/2023] [Revised: 07/01/2023] [Accepted: 07/25/2023] [Indexed: 08/10/2023]
Abstract
The evolutionary origin of eukaryotes spurred the transition from prokaryotic-like translation to a more sophisticated, eukaryotic translation. During this process, successive gene duplication of a single, primordial eIF4E gene encoding the mRNA cap-binding protein eukaryotic translation initiation factor 4E (eIF4E) gave rise to a plethora of paralog genes across eukaryotes that underwent further functional diversification in RNA metabolism. The ability to take different roles is due to eIF4E promiscuity in binding many partner proteins, rendering eIF4E a highly versatile and multifunctional player that functions as a molecular wildcard. Thus, in metazoans, eIF4E paralogs are involved in various processes, including messenger RNA (mRNA) processing, export, translation, storage, and decay. Moreover, some paralogs display differential expression in tissues and developmental stages and show variable biochemical properties. In this review, we discuss recent advances shedding light on the functional diversification of eIF4E in metazoans. We emphasise humans and two phylogenetically distant species which have become paradigms for studies on development, namely the fruit fly Drosophila melanogaster and the roundworm Caenorhabditis elegans.
Collapse
Affiliation(s)
- Greco Hernández
- mRNA and Cancer Laboratory, Unit of Biomedical Research on Cancer, National Institute of Cancer (Instituto Nacional de Cancerología, INCan), 22 San Fernando Ave., Tlalpan, Mexico City, 14080, Mexico
| | - Paula Vazquez-Pianzola
- Institute of Cell Biology, University of Bern, Baltzerstrasse 4, Berne, 3012, Switzerland
| |
Collapse
|
5
|
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.
Collapse
|
6
|
Deng J, Lin J, Liu C, Li J, Cai J, Zhou X, Li X. N7-methylguanosine methylation-related regulator genes as biological markers in predicting prognosis for melanoma. Sci Rep 2022; 12:21082. [PMID: 36473947 PMCID: PMC9726938 DOI: 10.1038/s41598-022-25698-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Accepted: 12/02/2022] [Indexed: 12/12/2022] Open
Abstract
The aim of this study is to find those N7-methylguanosine (m7G) methylation-related regulator genes (m7GMRRGs) which were associated with melanoma prognosis and use them to develop a prognostic prediction model. Clinical information was retrieved online from The Cancer Gene Atlas (TCGA) and the Gene Expression Omnibus (GEO). R software was used to extract m7GMRRGs by differential expression analysis. To create a prognostic risk model, univariate and multivariate Cox regression analyses were employed for the evaluation of the prognostic significance of m7G methylation modifiers. Internal validation using cohort from TCGA (training set) and external validation using cohort from GEO (validation set) of the model were carried out. The model's predictive performance was confirmed by using the Kaplan-Meier, univariate, and multivariate Cox regression, and receiver operating characteristic curve (ROC) by constructing column line plots incorporating clinical factor characteristics. Immune infiltration analyses were performed to assess the immune function of m7GMRRGs. Drug sensitivity analysis was conducted to study chemotherapeutic drug treatment cues. Prognostic models using four m7GMRRGs (EIF4E3, LARP1, NCBP3, and IFIT5) showed good prognostic power in training and validation sets. The area under the curve (AUC) at 1, 3, and 5 years for GEO-melanoma were 0.689, 0.704, and 0.726, respectively. The prediction model could distinctly classify patients with melanoma into different risk subgroups (P < 0.001 for TCGA-melanoma and P < 0.05 for GEO-melanoma). Clinical characteristics were taken into account in Cox regression and AUC analysis, which highlighted that the risk score served as an independent risk factor determining the prognosis of patients with melanoma. Immuno-infiltration analysis showed that m7GMRRGs could potentially regulate CD8+ T cells as well as regulatory T cells (Treg cells). Results of our study indicate a association between m7GMRRGs and melanoma prognosis, and the prognostic prediction model using m7GMRRGs may predict the prognosis of patients with melanoma well. Nevertheless, these results may provide a clue for potential better options of melanoma treatment but need further validation in futural studies.
Collapse
Affiliation(s)
- Jiehua Deng
- grid.443385.d0000 0004 1798 9548Department of Plastic and Aesthetic Surgery, The Second Affiliated Hospital of Guilin Medical University, No. 212 Renmin Road, Lingui District, Guilin, 541199 Guangxi Zhuang Autonomous Region China
| | - Jiahua Lin
- grid.488137.10000 0001 2267 2324College of Otolaryngology Head and Neck Surgery, Chinese PLA General Hospital, Chinese PLA Medical School, 28 Fuxing Road, Beijing, 100853 China ,Department of Neurosurgery, The 924th Hospital of the Chinese People’s Liberation Army Joint Logistic Support Force, Guilin, 541002 Guangxi Zhuang Autonomous Region China
| | - Chang Liu
- grid.443385.d0000 0004 1798 9548Department of Plastic and Aesthetic Surgery, The Second Affiliated Hospital of Guilin Medical University, No. 212 Renmin Road, Lingui District, Guilin, 541199 Guangxi Zhuang Autonomous Region China
| | - Jiasong Li
- grid.443385.d0000 0004 1798 9548Department of Plastic and Aesthetic Surgery, The Second Affiliated Hospital of Guilin Medical University, No. 212 Renmin Road, Lingui District, Guilin, 541199 Guangxi Zhuang Autonomous Region China
| | - Jun Cai
- grid.443385.d0000 0004 1798 9548Department of Plastic and Aesthetic Surgery, The Second Affiliated Hospital of Guilin Medical University, No. 212 Renmin Road, Lingui District, Guilin, 541199 Guangxi Zhuang Autonomous Region China
| | - Xiyu Zhou
- grid.443385.d0000 0004 1798 9548Department of Plastic and Aesthetic Surgery, The Second Affiliated Hospital of Guilin Medical University, No. 212 Renmin Road, Lingui District, Guilin, 541199 Guangxi Zhuang Autonomous Region China
| | - Xiong Li
- grid.443385.d0000 0004 1798 9548Department of Plastic and Aesthetic Surgery, The Second Affiliated Hospital of Guilin Medical University, No. 212 Renmin Road, Lingui District, Guilin, 541199 Guangxi Zhuang Autonomous Region China
| |
Collapse
|
7
|
Bartoszewska S, Collawn JF, Bartoszewski R. The Role of the Hypoxia-Related Unfolded Protein Response (UPR) in the Tumor Microenvironment. Cancers (Basel) 2022; 14:4870. [PMID: 36230792 PMCID: PMC9562011 DOI: 10.3390/cancers14194870] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Revised: 09/29/2022] [Accepted: 10/03/2022] [Indexed: 11/19/2022] Open
Abstract
Despite our understanding of the unfolded protein response (UPR) pathways, the crosstalk between the UPR and the complex signaling networks that different cancers utilize for cell survival remains to be, in most cases, a difficult research barrier. A major problem is the constant variability of different cancer types and the different stages of cancer as well as the complexity of the tumor microenvironments (TME). This complexity often leads to apparently contradictory results. Furthermore, the majority of the studies that have been conducted have utilized two-dimensional in vitro cultures of cancer cells that were exposed to continuous hypoxia, and this approach may not mimic the dynamic and cyclic conditions that are found in solid tumors. Here, we discuss the role of intermittent hypoxia, one of inducers of the UPR in the cellular component of TME, and the way in which intermittent hypoxia induces high levels of reactive oxygen species, the activation of the UPR, and the way in which cancer cells modulate the UPR to aid in their survival. Although the past decade has resulted in defining the complex, novel non-coding RNA-based regulatory networks that modulate the means by which hypoxia influences the UPR, we are now just to beginning to understand some of the connections between hypoxia, the UPR, and the TME.
Collapse
Affiliation(s)
- Sylwia Bartoszewska
- Department of Inorganic Chemistry, Medical University of Gdansk, 80-416 Gdansk, Poland
| | - James F. Collawn
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Rafal Bartoszewski
- Department of Biophysics, Faculty of Biotechnology, University of Wroclaw, F. Joliot-Curie 14a Street, 50-383 Wroclaw, Poland
| |
Collapse
|
8
|
Méndez-Solís O, Bendjennat M, Naipauer J, Theodoridis PR, Ho JJD, Verdun RE, Hare JM, Cesarman E, Lee S, Mesri EA. Kaposi's sarcoma herpesvirus activates the hypoxia response to usurp HIF2α-dependent translation initiation for replication and oncogenesis. Cell Rep 2021; 37:110144. [PMID: 34965440 PMCID: PMC9121799 DOI: 10.1016/j.celrep.2021.110144] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 05/19/2021] [Accepted: 11/29/2021] [Indexed: 12/19/2022] Open
Abstract
Kaposi's sarcoma herpesvirus (KSHV) is an angiogenesis-inducing oncovirus whose ability to usurp the oxygen-sensing machinery is central to its oncogenicity. By upregulating the hypoxia-inducible factors (HIFs), KSHV reprograms infected cells to a hypoxia-like state, triggering angiogenesis. Here we identify a link between KSHV replicative biology and oncogenicity by showing that KSHV's ability to regulate HIF2α levels and localization to the endoplasmic reticulum (ER) in normoxia enables translation of viral lytic mRNAs through the HIF2α-regulated eIF4E2 translation-initiation complex. This mechanism of translation in infected cells is critical for lytic protein synthesis and contributes to KSHV-induced PDGFRA activation and VEGF secretion. Thus, KSHV regulation of the oxygen-sensing machinery allows virally infected cells to initiate translation via the mTOR-dependent eIF4E1 or the HIF2α-dependent, mTOR-independent, eIF4E2. This "translation initiation plasticity" (TRIP) is an oncoviral strategy used to optimize viral protein expression that links molecular strategies of viral replication to angiogenicity and oncogenesis.
Collapse
Affiliation(s)
- Omayra Méndez-Solís
- Tumor Biology Program, Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, FL 33136, USA; Miami Center for AIDS Research, Department of Microbiology and Immunology, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Mourad Bendjennat
- Tumor Biology Program, Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, FL 33136, USA; Miami Center for AIDS Research, Department of Microbiology and Immunology, University of Miami Miller School of Medicine, Miami, FL 33136, USA; Department of Radiation Oncology, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Julian Naipauer
- Tumor Biology Program, Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, FL 33136, USA; Miami Center for AIDS Research, Department of Microbiology and Immunology, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Phaedra R Theodoridis
- Tumor Biology Program, Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, FL 33136, USA; Department of Biochemistry and Molecular Biology, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - J J David Ho
- Tumor Biology Program, Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, FL 33136, USA; Department of Biochemistry and Molecular Biology, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Ramiro E Verdun
- Cancer Epigenetics Program, Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, FL 33136, USA; Department of Medicine, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Joshua M Hare
- Department of Medicine, University of Miami Miller School of Medicine, Miami, FL 33136, USA; Interdisciplinary Stem Cell Institute, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Ethel Cesarman
- Department of Pathology and Laboratory Medicine, Weill Cornell Medicine, New York, NY 10021, USA
| | - Stephen Lee
- Tumor Biology Program, Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, FL 33136, USA; Department of Biochemistry and Molecular Biology, University of Miami Miller School of Medicine, Miami, FL 33136, USA.
| | - Enrique A Mesri
- Tumor Biology Program, Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, FL 33136, USA; Miami Center for AIDS Research, Department of Microbiology and Immunology, University of Miami Miller School of Medicine, Miami, FL 33136, USA.
| |
Collapse
|
9
|
|
10
|
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.
Collapse
|
11
|
Wu S, Wagner G. Deep computational analysis details dysregulation of eukaryotic translation initiation complex eIF4F in human cancers. Cell Syst 2021; 12:907-923.e6. [PMID: 34358439 DOI: 10.1016/j.cels.2021.07.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 04/22/2021] [Accepted: 07/09/2021] [Indexed: 12/28/2022]
Abstract
eIF4F plays diverse roles in human cancers, which complicate the development of an overarching understanding of its functional and regulatory impacts across tumor types. Typically, eIF4F drives initiation from the mRNA 5' end (cap) and is composed of eIF4G1, eIF4A1, and cap-binding eIF4E. Cap-independent initiation is possible without eIF4E, from internal ribosomal entry sites (IRESs). By analyzing large public datasets, we found that cancers selectively overexpress EIF4G1 more than EIF4E. That expression imbalance supports EIF4G1 as a prognostic indicator in patients with cancer. It also attenuates "housekeeping" pathways that are usually regulated in a tissue-specific manner via cap-dependent initiation in healthy tissues and reinforce regulation of cancer-preferred pathways in cap-independent contexts. Cap-independent initiation is mechanistically attributable to eIF4G1 hyperphosphorylation that promotes binding to eIF4A1 and reduced eIF4E availability. Collectively, these findings reveal a novel model of dysregulated eIF4F function and highlight the clinical relevance of cap-(in)dependent initiation in cancer.
Collapse
Affiliation(s)
- Su Wu
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA.
| | - Gerhard Wagner
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA.
| |
Collapse
|
12
|
Metge BJ, Kammerud SC, Pruitt HC, Shevde LA, Samant RS. Hypoxia re-programs 2'-O-Me modifications on ribosomal RNA. iScience 2020; 24:102010. [PMID: 33490918 PMCID: PMC7811136 DOI: 10.1016/j.isci.2020.102010] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 12/07/2020] [Accepted: 12/24/2020] [Indexed: 02/07/2023] Open
Abstract
Hypoxia is one of the critical stressors encountered by various cells of the human body under diverse pathophysiologic conditions including cancer and has profound impacts on several metabolic and physiologic processes. Hypoxia prompts internal ribosome entry site (IRES)-mediated translation of key genes, such as VEGF, that are vital for tumor progression. Here, we describe that hypoxia remarkably upregulates RNA Polymerase I activity. We discovered that in hypoxia, rRNA shows a different methylation pattern compared to normoxia. Heterogeneity in ribosomes due to the diversity of ribosomal RNA and protein composition has been postulated to generate “specialized ribosomes” that differentially regulate translation. We find that in hypoxia, a sub-set of differentially methylated ribosomes recognizes the VEGF-C IRES, suggesting that ribosomal heterogeneity allows for altered ribosomal functions in hypoxia. Chronic hypoxia stimulates RNA Pol I activity In hypoxia, a pool of specialized rRNA translates VEGFC IRES Hypoxia changes 2′-O-Me modification - epitranscriptomic marks on rRNA
Collapse
Affiliation(s)
- Brandon J Metge
- Department of Pathology, University of Alabama at Birmingham, WTI 320E 1824 6 Avenue South, Birmingham, AL 35233, USA
| | - Sarah C Kammerud
- Department of Pathology, University of Alabama at Birmingham, WTI 320E 1824 6 Avenue South, Birmingham, AL 35233, USA
| | - Hawley C Pruitt
- Department of Pathology, University of Alabama at Birmingham, WTI 320E 1824 6 Avenue South, Birmingham, AL 35233, USA
| | - Lalita A Shevde
- Department of Pathology, University of Alabama at Birmingham, WTI 320E 1824 6 Avenue South, Birmingham, AL 35233, USA.,O'Neal Comprehensive Cancer Center, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Rajeev S Samant
- Department of Pathology, University of Alabama at Birmingham, WTI 320E 1824 6 Avenue South, Birmingham, AL 35233, USA.,Birmingham VA Medical Center, Birmingham, AL, USA
| |
Collapse
|
13
|
Lee LJ, Papadopoli D, Jewer M, Del Rincon S, Topisirovic I, Lawrence MG, Postovit LM. Cancer Plasticity: The Role of mRNA Translation. Trends Cancer 2020; 7:134-145. [PMID: 33067172 PMCID: PMC8023421 DOI: 10.1016/j.trecan.2020.09.005] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 09/08/2020] [Accepted: 09/15/2020] [Indexed: 12/12/2022]
Abstract
Tumor progression is associated with dedifferentiated histopathologies concomitant with cancer cell survival within a changing, and often hostile, tumor microenvironment. These processes are enabled by cellular plasticity, whereby intracellular cues and extracellular signals are integrated to enable rapid shifts in cancer cell phenotypes. Cancer cell plasticity, at least in part, fuels tumor heterogeneity and facilitates metastasis and drug resistance. Protein synthesis is frequently dysregulated in cancer, and emerging data suggest that translational reprograming collaborates with epigenetic and metabolic programs to effectuate phenotypic plasticity of neoplasia. Herein, we discuss the potential role of mRNA translation in cancer cell plasticity, highlight emerging histopathological correlates, and deliberate on how this is related to efforts to improve understanding of the complex tumor ecology.
Collapse
Affiliation(s)
- Laura J Lee
- Department of Oncology, University of Alberta, Edmonton, AB, Canada
| | - David Papadopoli
- Lady Davis Institute, Gerald Bronfman Department of Oncology and Departments of Biochemistry and Experimental Medicine, McGill University, Montreal, QC, Canada
| | - Michael Jewer
- Department of Oncology, University of Alberta, Edmonton, AB, Canada
| | - Sonia Del Rincon
- Lady Davis Institute, Gerald Bronfman Department of Oncology and Departments of Biochemistry and Experimental Medicine, McGill University, Montreal, QC, Canada
| | - Ivan Topisirovic
- Lady Davis Institute, Gerald Bronfman Department of Oncology and Departments of Biochemistry and Experimental Medicine, McGill University, Montreal, QC, Canada.
| | - Mitchell G Lawrence
- Biomedicine Discovery Institute Cancer Program, Prostate Cancer Research Group, Department of Anatomy and Developmental Biology, Monash University, Clayton, VIC 3800, Australia; Peter MacCallum Cancer Centre, Melbourne, VIC 3000, Australia; Sir Peter MacCallum Department of Oncology, The University of Melbourne, Parkville, VIC 3010, Australia.
| | - Lynne-Marie Postovit
- Department of Oncology, University of Alberta, Edmonton, AB, Canada; Department of Biomedical and Molecular Sciences, Queen's University, Kingston, ON, Canada.
| |
Collapse
|
14
|
The Effect of MicroRNA-101 on Angiogenesis of Human Umbilical Vein Endothelial Cells during Hypoxia and in Mice with Myocardial Infarction. BIOMED RESEARCH INTERNATIONAL 2020; 2020:5426971. [PMID: 32953883 PMCID: PMC7487113 DOI: 10.1155/2020/5426971] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 06/10/2020] [Accepted: 08/05/2020] [Indexed: 12/15/2022]
Abstract
Background Previous studies showed that recanalization and angiogenesis within the infarct region are of vital importance to the survival of myocardial cells during the treatment of acute myocardial infarction (AMI). Methods In this study, EdU cell proliferation assay, Transwell assay, scratch wound assay, and tube formation assay were used. Twelve bioinformatics analysis packages were used to predict the target genes of miR-101. Target genes were verified by luciferase reporter generation and assay, fluorescent quantitative PCR, and western blotting. Animal model and treatments were detected by M-mode echocardiography and immunofluorescent staining of CD31, Ki67, and α-SMA. Results AgomiR-101 significantly enhanced HUVEC proliferation, migration, and tube formation. A double-luciferase reporter assay revealed that the hsa-miR-101 mimic attenuated the activity of the EIF4E3′-UTR-wt type plasmid by 36%. The expression levels of HIF-1α and VEGF-A in the scrambled RNA group were significantly lower than those in the EIF4E3 siRNA and agomiR-101 groups. The left ventricular ejection fraction of the AMI+Adv-miR-101 group was significantly higher than that of the AMI+Adv-null and Sham+Adv-null groups. The proliferation of vessel cells in the peripheral infarcted myocardium was higher in the AMI+Adv-miR-101 group than that in the AMI+Adv-null and Sham+Adv-null groups. Conclusion MiR-101 can promote angiogenesis in the region surrounding the myocardial infarction.
Collapse
|
15
|
Impact of Eukaryotic Translation Initiation Factors on Breast Cancer: Still Much to Investigate. Cancers (Basel) 2020; 12:cancers12071984. [PMID: 32708122 PMCID: PMC7409344 DOI: 10.3390/cancers12071984] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Revised: 07/04/2020] [Accepted: 07/08/2020] [Indexed: 12/11/2022] Open
Abstract
Breast carcinoma (BC) remains one of the most serious health problems. It is a heterogeneous entity, and mainly classified according to receptor status for estrogen (ER), progesterone (PR) and egf (HER2/Neu), as well as the proliferation marker ki67. Gene expression in eukaryotes is regulated at the level of both gene transcription and translation, where eukaryotic initiation factors (eIFs) are key regulators of protein biosynthesis. Aberrant translation results in an altered cellular proteome, and this clearly effects cell growth supporting tumorigenesis. The relationship between various eIFs and BC entities, as well as the related regulatory mechanisms, has meanwhile become a focus of scientific interest. Here, we give an overview on the current research state of eIF function, focusing on BC.
Collapse
|
16
|
Ho JJD, Balukoff NC, Theodoridis PR, Wang M, Krieger JR, Schatz JH, Lee S. A network of RNA-binding proteins controls translation efficiency to activate anaerobic metabolism. Nat Commun 2020; 11:2677. [PMID: 32472050 PMCID: PMC7260222 DOI: 10.1038/s41467-020-16504-1] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Accepted: 04/30/2020] [Indexed: 01/30/2023] Open
Abstract
Protein expression evolves under greater evolutionary constraint than mRNA levels, and translation efficiency represents a primary determinant of protein levels during stimuli adaptation. This raises the question as to the translatome remodelers that titrate protein output from mRNA populations. Here, we uncover a network of RNA-binding proteins (RBPs) that enhances the translation efficiency of glycolytic proteins in cells responding to oxygen deprivation. A system-wide proteomic survey of translational engagement identifies a family of oxygen-regulated RBPs that functions as a switch of glycolytic intensity. Tandem mass tag-pulse SILAC (TMT-pSILAC) and RNA sequencing reveals that each RBP controls a unique but overlapping portfolio of hypoxic responsive proteins. These RBPs collaborate with the hypoxic protein synthesis apparatus, operating as a translation efficiency checkpoint that integrates upstream mRNA signals to activate anaerobic metabolism. This system allows anoxia-resistant animals and mammalian cells to initiate anaerobic glycolysis and survive hypoxia. We suggest that an oxygen-sensitive RBP cluster controls anaerobic metabolism to confer hypoxia tolerance. mRNA translation efficiency is regulated in response to stimuli. Here the authors employ mass spectrometry analysis of ribosome fractions and show that under hypoxia, oxygen-sensitive RNA binding proteins enhance the translation efficiency of glycolysis pathway transcripts.
Collapse
Affiliation(s)
- J J David Ho
- Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, FL, 33136, USA.,Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, FL, 33136, USA.,Division of Hematology, Department of Medicine, Miller School of Medicine, University of Miami, Miami, FL, 33136, USA
| | - Nathan C Balukoff
- Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, FL, 33136, USA.,Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, FL, 33136, USA
| | - Phaedra R Theodoridis
- Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, FL, 33136, USA.,Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, FL, 33136, USA
| | - Miling Wang
- Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, FL, 33136, USA.,Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, FL, 33136, USA
| | - Jonathan R Krieger
- The SickKids Proteomics, Analytics, Robotics & Chemical Biology Centre (SPARC Biocentre), The Hospital for Sick Children, Toronto, ON, M5G 1X8, Canada.,Bioinformatics Solutions Inc., Waterloo, ON, N2L 6J2, Canada
| | - Jonathan H Schatz
- Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, FL, 33136, USA.,Division of Hematology, Department of Medicine, Miller School of Medicine, University of Miami, Miami, FL, 33136, USA
| | - Stephen Lee
- Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, FL, 33136, USA. .,Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, FL, 33136, USA. .,Department of Urology, Miller School of Medicine, University of Miami, Miami, 33136, USA.
| |
Collapse
|
17
|
Bartoszewska S, Collawn JF. Unfolded protein response (UPR) integrated signaling networks determine cell fate during hypoxia. Cell Mol Biol Lett 2020; 25:18. [PMID: 32190062 PMCID: PMC7071609 DOI: 10.1186/s11658-020-00212-1] [Citation(s) in RCA: 75] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Accepted: 02/26/2020] [Indexed: 02/06/2023] Open
Abstract
During hypoxic conditions, cells undergo critical adaptive responses that include the up-regulation of hypoxia-inducible proteins (HIFs) and the induction of the unfolded protein response (UPR). While their induced signaling pathways have many distinct targets, there are some important connections as well. Despite the extensive studies on both of these signaling pathways, the exact mechanisms involved that determine survival versus apoptosis remain largely unexplained and therefore beyond therapeutic control. Here we discuss the complex relationship between the HIF and UPR signaling pathways and the importance of understanding how these pathways differ between normal and cancer cell models.
Collapse
Affiliation(s)
- Sylwia Bartoszewska
- Department of Inorganic Chemistry, Medical University of Gdansk, Gdansk, Poland
| | - James F. Collawn
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, USA
| |
Collapse
|
18
|
DEAD Box Protein Family Member DDX28 Is a Negative Regulator of Hypoxia-Inducible Factor 2α- and Eukaryotic Initiation Factor 4E2-Directed Hypoxic Translation. Mol Cell Biol 2020; 40:MCB.00610-19. [PMID: 31907278 DOI: 10.1128/mcb.00610-19] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Accepted: 12/20/2019] [Indexed: 12/27/2022] Open
Abstract
Hypoxia is a deficiency in oxygen delivery to tissues and is connected to physiological and pathophysiological processes such as embryonic development and cancer. The master regulators of oxygen homeostasis in mammalian cells are the heterodimeric hypoxia-inducible transcription factors 1 and 2 (HIF-1 and HIF-2, respectively). The oxygen-labile HIF-2α subunit has been implicated not only in transcription but also as a regulator of eukaryotic initiation factor 4E2 (eIF4E2)-directed hypoxic translation. Here, we have identified the DEAD box protein family member DDX28 as an interactor and negative regulator of HIF-2α that suppresses HIF-2α's ability to activate eIF4E2-directed translation. Stable silencing of DDX28 via short hairpin RNA (shRNA) in hypoxic human U87MG glioblastoma cells caused an increase of eIF4E2 binding to the m7GTP cap structure and the translation of eIF4E2 target mRNAs (including the HIF-2α mRNA itself). DDX28 depletion elevated nuclear and cytoplasmic HIF-2α protein, but HIF-2α transcriptional activity did not increase, possibly due to its already high nuclear abundance in hypoxic control cells. Depletion of DDX28 conferred a proliferative advantage to hypoxic, but not normoxic, cells. DDX28 protein levels are reduced in several cancers, including gliomas, relative to levels in normal tissue. Therefore, we uncover a regulatory mechanism for this potential tumor suppressor in the repression of HIF-2α- and eIF4E2-mediated translation activation of oncogenic mRNAs.
Collapse
|
19
|
García-Aguilar A, Martínez-Reyes I, Cuezva JM. Changes in the Turnover of the Cellular Proteome during Metabolic Reprogramming: A Role for mtROS in Proteostasis. J Proteome Res 2019; 18:3142-3155. [DOI: 10.1021/acs.jproteome.9b00239] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Ana García-Aguilar
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa (CSIC-UAM), Centro de Investigación Biomédica en Red de Enfermedades Raras CIBERER-ISCIII, Instituto de Investigación Hospital 12 de Octubre (i+12), Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Inmaculada Martínez-Reyes
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa (CSIC-UAM), Centro de Investigación Biomédica en Red de Enfermedades Raras CIBERER-ISCIII, Instituto de Investigación Hospital 12 de Octubre (i+12), Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - José M. Cuezva
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa (CSIC-UAM), Centro de Investigación Biomédica en Red de Enfermedades Raras CIBERER-ISCIII, Instituto de Investigación Hospital 12 de Octubre (i+12), Universidad Autónoma de Madrid, 28049 Madrid, Spain
| |
Collapse
|
20
|
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: 170] [Impact Index Per Article: 34.0] [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.
Collapse
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
| |
Collapse
|
21
|
Mesenchymal stem cells of Systemic Sclerosis patients, derived from different sources, show a profibrotic microRNA profiling. Sci Rep 2019; 9:7144. [PMID: 31073190 PMCID: PMC6509164 DOI: 10.1038/s41598-019-43638-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Accepted: 04/24/2019] [Indexed: 02/06/2023] Open
Abstract
Systemic Sclerosis (SSc) is a disease with limited therapeutic possibilities. Mesenchymal stem cells (MSCs)-therapy could be a promising therapeutic option, however the ideal MSCs source has not yet been found. To address this problem, we perform comparison between bone marrow (BM)-MSCs and adipose (A)-MSCs, by the miRs expression profile, to identify the gene modulation in these two MSCs source. MicroRNAs (miRs) are RNAs sequences, regulating gene expression and MSCs, derived from different tissues, may differently respond to the SSc microenvironment. The miRs array was used for the miRs profiling and by DIANA-mirPath tool we identified the biological functions of the dysregulated miRs. In SSc-BM-MSCs, 6 miRs were significantly down-regulated and 4 miRs up-regulated. In SSc-A-MSCs, 11 miRs were significantly down-regulated and 3 miRs up-regulated. Interestingly, in both the sources, the involved pathways included the senescence mechanisms and the pro-fibrotic behaviour. Furthermore, both the MSCs sources showed potential compensatory ability. A deeper knowledge of this miRs signature might give more information about some pathogenic steps of the disease and in the same time clarify the possible therapeutic role of autologous MSCs in the regenerative therapy in SSc.
Collapse
|
22
|
Vanillic Acid Suppresses HIF-1α Expression via Inhibition of mTOR/p70S6K/4E-BP1 and Raf/MEK/ERK Pathways in Human Colon Cancer HCT116 Cells. Int J Mol Sci 2019; 20:ijms20030465. [PMID: 30678221 PMCID: PMC6387037 DOI: 10.3390/ijms20030465] [Citation(s) in RCA: 66] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Revised: 01/11/2019] [Accepted: 01/15/2019] [Indexed: 12/30/2022] Open
Abstract
Hypoxia-inducible factor 1 (HIF-1) plays a pivotal role in tumor adaptation to microenvironmental hypoxia, and it also exerts important roles in angiogenesis and tumor development. Vanillic acid is a dietary phenolic compound reported to exhibit anticancer properties. However, the mechanisms by which vanillic acid inhibits tumor growth are not fully understood. Here, we investigated the effect of vanillic acid on HIF-1α activation. Vanillic acid significantly inhibits HIF-1α expression induced by hypoxia in various human cancer cell lines. Further analysis revealed that vanillic acid inhibited HIF-1α protein synthesis. Neither the HIF-1α protein degradation rate nor the steady-state HIF-1α mRNA levels were affected by vanillic acid. Moreover, vanillic acid inhibited HIF-1α expression by suppressing mammalian target of rapamycin/p70 ribosomal protein S6 kinase/eukaryotic initiation factor 4E-binding protein-1 and Raf/extracellular signal-regulated kinase (ERK) kinase (MEK)/ERK pathways. We found that vanillic acid dose-dependently inhibited VEGF and EPO protein expressions and disrupted tube formation. The results suggest that vanillic acid effectively inhibits angiogenesis. Flow cytometry analysis demonstrated that vanillic acid significantly induced G1 phase arrest and inhibited the proliferation of human colon cancer HCT116 cells. In vivo experiments confirmed that vanillic acid treatment caused significant inhibition of tumor growth in a xenografted tumor model. These studies reveal that vanillic acid is an effective inhibitor of HIF-1α and provides new perspectives into the mechanism of its antitumor activity.
Collapse
|
23
|
Shen P, Reineke LC, Knutsen E, Chen M, Pichler M, Ling H, Calin GA. Metformin blocks MYC protein synthesis in colorectal cancer via mTOR-4EBP-eIF4E and MNK1-eIF4G-eIF4E signaling. Mol Oncol 2018; 12:1856-1870. [PMID: 30221473 PMCID: PMC6210051 DOI: 10.1002/1878-0261.12384] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Revised: 08/04/2018] [Accepted: 08/14/2018] [Indexed: 12/26/2022] Open
Abstract
The antidiabetic drug metformin has been associated with reduced colorectal cancer (CRC) risk and improved prognosis of CRC patients. However, the detailed mechanisms underlying such beneficial effects remain unknown. In this study, we aimed to evaluate metformin activity in CRC models and unveil the underlying molecular mechanisms. We showed that metformin inhibits CRC cell proliferation by arresting cells in the G1 phase of the cell cycle and dramatically reduces colony formation of CRC cells. We discovered that metformin causes a robust reduction of MYC protein level. Through the use of luciferase assay and coincubation with either protein synthesis or proteasome inhibitors, we demonstrated that regulation of MYC by metformin is independent of the proteasome and 3' UTR-mediated regulation, but depends on protein synthesis. Data from polysome profiling and ribopuromycylation assays showed that metformin induced widespread inhibition of protein synthesis. Repression of protein synthesis by metformin preferentially affects cell cycle-associated proteins, by altering signaling through the mTOR-4EBP-eIF4E and MNK1-eIF4G-eIF4E axes. The inhibition of MYC protein synthesis may underlie metformin's beneficial effects on CRC risk and prognosis.
Collapse
Affiliation(s)
- Peng Shen
- Department of Oncology, Nanfang Hospital, Southern Medical University, Guangzhou, China.,The First School of Clinical Medicine, Southern Medical University, Guangzhou, China.,Department of Experimental Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Lucas C Reineke
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX, USA
| | - Erik Knutsen
- Department of Experimental Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.,Department of Medical Biology, Faculty of Health Sciences, UiT - The Arctic University of Norway, Tromsø, Norway
| | - Meng Chen
- Department of Experimental Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Martin Pichler
- Department of Experimental Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.,Division of Oncology, Research Unit of Non-Coding RNA and Genome Editing in Cancer, Medical University of Graz, Austria
| | - Hui Ling
- Department of Experimental Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - George A Calin
- Department of Experimental Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.,The Center for RNA Interference and Non-Coding RNAs, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| |
Collapse
|
24
|
Chu J, Pelletier J. Therapeutic Opportunities in Eukaryotic Translation. Cold Spring Harb Perspect Biol 2018; 10:cshperspect.a032995. [PMID: 29440069 DOI: 10.1101/cshperspect.a032995] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The ability to block biological processes with selective small molecules provides advantages distinct from most other experimental approaches. These include rapid time to onset, swift reversibility, ability to probe activities in manners that cannot be accessed by genetic means, and the potential to be further developed as therapeutic agents. Small molecule inhibitors can also be used to alter expression and activity without affecting the stoichiometry of interacting partners. These tenets have been especially evident in the field of translation. Small molecule inhibitors were instrumental in enabling investigators to capture short-lived complexes and characterize specific steps of protein synthesis. In addition, several drugs that are the mainstay of modern antimicrobial drug therapy are potent inhibitors of prokaryotic translation. Currently, there is much interest in targeting eukaryotic translation as decades of research have revealed that deregulated protein synthesis in cancer cells represents a targetable vulnerability. In addition to being potential therapeutics, small molecules that manipulate translation have also been shown to influence cognitive processes such as memory. In this review, we focus on small molecule modulators that target the eukaryotic translation initiation apparatus and provide an update on their potential application to the treatment of disease.
Collapse
Affiliation(s)
- Jennifer Chu
- Department of Biochemistry, McGill University, Montreal, Quebec H3G 1Y6, Canada
| | - Jerry Pelletier
- Department of Biochemistry, McGill University, Montreal, Quebec H3G 1Y6, Canada.,Department of Oncology, McGill University, Montreal, Quebec H3G 1Y6, Canada.,Rosalind and Morris Goodman Cancer Research Center, McGill University, Montreal, Quebec H3G 1Y6, Canada
| |
Collapse
|
25
|
Bhalla K, Jaber S, Nahid M N, Underwood K, Beheshti A, Landon A, Bhandary B, Bastian P, Evens AM, Haley J, Polster B, Gartenhaus RB. Role of hypoxia in Diffuse Large B-cell Lymphoma: Metabolic repression and selective translation of HK2 facilitates development of DLBCL. Sci Rep 2018; 8:744. [PMID: 29335581 PMCID: PMC5768748 DOI: 10.1038/s41598-018-19182-8] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Accepted: 12/22/2017] [Indexed: 02/08/2023] Open
Abstract
Published molecular profiling studies in patients with lymphoma suggested the influence of hypoxia inducible factor-1 alpha (HIF1α) targets in prognosis of DLBCL. Yet, the role of hypoxia in hematological malignancies remains unclear. We observed that activation of HIF1α resulted in global translation repression during hypoxic stress in DLBCL. Protein translation efficiency as measured using 35S-labeled methionine incorporation revealed a ≥50% reduction in translation upon activation of HIF1α. Importantly, translation was not completely inhibited and expression of clinically correlated hypoxia targets such as GLUT1, HK2, and CYT-C was found to be refractory to translational repression under hypoxia in DLBCL cells. Notably, hypoxic induction of these genes was not observed in normal primary B-cells. Translational repression was coupled with a decrease in mitochondrial function. Screening of primary DLBCL patient samples revealed that expression of HK2, which encodes for the enzyme hexokinase 2, was significantly correlated with DLBCL phenotype. Genetic knockdown studies demonstrated that HK2 is required for promoting growth of DLBCL under hypoxic stress. Altogether, our findings provide strong support for the direct contribution of HK2 in B-cell lymphoma development and suggest that HK2 is a key metabolic driver of the DLBCL phenotype.
Collapse
Affiliation(s)
- Kavita Bhalla
- Marlene and Stewart Greenebaum Comprehensive Cancer Center, University of Maryland, Department of Medicine, Baltimore, MD, 21201, USA.
| | - Sausan Jaber
- University of Maryland, Department of Biochemistry and Molecular Biology, Baltimore, MD, 21201, USA
| | - Nanaji Nahid M
- Veterans Administration Medical Center, Baltimore, MD, 21201, USA
| | - Karen Underwood
- University of Maryland, Flow Cytometry Core, Greenebaum Comprehensive Cancer Center, Baltimore, MD, 21201, USA
| | | | - Ari Landon
- Yale School of Medicine, Yale University, New Haven, CT, 06520, USA
| | - Binny Bhandary
- Marlene and Stewart Greenebaum Comprehensive Cancer Center, University of Maryland, Department of Medicine, Baltimore, MD, 21201, USA
| | - Paul Bastian
- National Institute on Aging, National Institutes of Health, Baltimore, MD, 21224, USA
| | | | - John Haley
- Department of Pathology, Stony Brook Medicine, Stony Brook, NY, 11794-8691, USA
| | - Brian Polster
- University of Maryland, Department of Biochemistry and Molecular Biology, Baltimore, MD, 21201, USA
| | - Ronald B Gartenhaus
- Marlene and Stewart Greenebaum Comprehensive Cancer Center, University of Maryland, Department of Medicine, Baltimore, MD, 21201, USA.
- Veterans Administration Medical Center, Baltimore, MD, 21201, USA.
| |
Collapse
|
26
|
Abe DO, Eskandari A, Suntharalingam K. Diflunisal-adjoined cobalt(iii)-polypyridyl complexes as anti-cancer stem cell agents. Dalton Trans 2018; 47:13761-13765. [DOI: 10.1039/c8dt03448f] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
We report a novel series of cobalt(iii)-polypridyl complexes that can selectively release diflunisal, a nonsteroidal anti-inflammatory drug, under reducing conditions.
Collapse
Affiliation(s)
- David O. Abe
- Department of Chemistry
- King's College London
- London
- UK
| | | | | |
Collapse
|
27
|
Wang S, Huo D, Ogundiran TO, Ojengbede O, Zheng W, Nathanson KL, Nemesure B, Ambs S, Olopade OI, Zheng Y. Association of breast cancer risk and the mTOR pathway in women of African ancestry in 'The Root' Consortium. Carcinogenesis 2017; 38:789-796. [PMID: 28582508 DOI: 10.1093/carcin/bgx055] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Accepted: 06/02/2017] [Indexed: 12/16/2022] Open
Abstract
Functional studies have elucidated the role of the mammalian target of rapamycin (mTOR) pathway in breast carcinogenesis, but to date, there is a paucity of data on its contribution to breast cancer risk in women of African ancestry. We examined 47628 SNPs in 61 mTOR pathway genes in the genome wide association study of breast cancer in the African Diaspora study (The Root consortium), which included 3686 participants (1657 cases). Pathway- and gene-level analyses were conducted using the adaptive rank truncated product (ARTP) test for 10994 SNPs that were not highly correlated (r2 < 0.8). Odds ratio (OR) and 95% confidence interval (CI) were estimated with logistic regression for each single-nucleotide polymorphism. The mTOR pathway was significantly associated with overall and estrogen receptor-negative (ER-) breast cancer risk (P = 0.003 and 0.03, respectively). PRKAG3 (Padj = 0.0018) and RPS6KA3 (Padj = 0.061) were the leading genes for the associations with overall breast cancer risk and ER- breast cancer risk, respectively. rs190843378 in PRKAG3 was statistically significant after gene-level adjustment for multiple comparisons (OR = 0.50 for each T allele, 95% CI = 0.38-0.66, Padj = 3.6E-05), with a statistical power of 0.914. These results provide new insights on the biological relevance of the mTOR pathway in breast cancer progression and underscore the need for more genetic epidemiology studies of breast cancer in the African Diaspora.
Collapse
Affiliation(s)
- Shengfeng Wang
- Department of Medicine, Center for Clinical Cancer Genetics and Global Health, University of Chicago, Chicago, IL, USA
| | - Dezheng Huo
- Department of Public Health Sciences, University of Chicago, Chicago, IL, USA
| | - Temidayo O Ogundiran
- Department of Surgery, College of Medicine, University of Ibadan, Ibadan, Nigeria
| | - Oladosu Ojengbede
- Center for Population and Reproductive Health, College of Medicine, University of Ibadan, Ibadan, Nigeria
| | - Wei Zheng
- Division of Epidemiology, Department of Medicine, Vanderbilt Epidemiology Center, Vanderbilt-Ingram Cancer Center, Vanderbilt University, Nashville, TN, USA
| | | | - Barbara Nemesure
- Department of Preventive Medicine, State University of New York at Stony Brook, Stony Brook, NY, USA
| | - Stefan Ambs
- Laboratory of Human Carcinogenesis, National Cancer Institute, Bethesda, MD, USA
| | | | - Yonglan Zheng
- To whom correspondence should be addressed. Tel: +1 773 702 1632; Fax: +1 773 834 1659;
| |
Collapse
|
28
|
Vaklavas C, Blume SW, Grizzle WE. Translational Dysregulation in Cancer: Molecular Insights and Potential Clinical Applications in Biomarker Development. Front Oncol 2017; 7:158. [PMID: 28798901 PMCID: PMC5526920 DOI: 10.3389/fonc.2017.00158] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Accepted: 07/06/2017] [Indexed: 01/04/2023] Open
Abstract
Although transcript levels have been traditionally used as a surrogate measure of gene expression, it is increasingly recognized that the latter is extensively and dynamically modulated at the level of translation (messenger RNA to protein). Over the recent years, significant progress has been made in dissecting the complex posttranscriptional mechanisms that regulate gene expression. This advancement in knowledge came hand in hand with the progress made in the methodologies to study translation both at gene-specific as well as global genomic level. The majority of translational control is exerted at the level of initiation; nonetheless, protein synthesis can be modulated at the level of translation elongation, termination, and recycling. Sequence and structural elements and epitranscriptomic modifications of individual transcripts allow for dynamic gene-specific modulation of translation. Cancer cells usurp the regulatory mechanisms that govern translation to carry out translational programs that lead to the phenotypic hallmarks of cancer. Translation is a critical nexus in neoplastic transformation. Multiple oncogenes and signaling pathways that are activated, upregulated, or mutated in cancer converge on translation and their transformative impact "bottlenecks" at the level of translation. Moreover, this translational dysregulation allows cancer cells to adapt to a diverse array of stresses associated with a hostile microenviroment and antitumor therapies. All elements involved in the process of translation, from the transcriptional template, the components of the translational machinery, to the proteins that interact with the transcriptome, have been found to be qualitatively and/or quantitatively perturbed in cancer. This review discusses the regulatory mechanisms that govern translation in normal cells and how translation becomes dysregulated in cancer leading to the phenotypic hallmarks of malignancy. We also discuss how dysregulated mediators or components of translation can be utilized as biomarkers with potential diagnostic, prognostic, or predictive significance. Such biomarkers have the potential advantage of uniform applicability in the face of inherent tumor heterogeneity and deoxyribonucleic acid instability. As translation becomes increasingly recognized as a process gone awry in cancer and agents are developed to target it, the utility and significance of these potential biomarkers is expected to increase.
Collapse
Affiliation(s)
- Christos Vaklavas
- Department of Medicine, Division of Hematology/Oncology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Scott W Blume
- Department of Medicine, Division of Hematology/Oncology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - William E Grizzle
- Department of Anatomic Pathology, University of Alabama at Birmingham, Birmingham, AL, United States
| |
Collapse
|
29
|
Translational control and the cancer cell response to stress. Curr Opin Cell Biol 2017; 45:102-109. [PMID: 28582681 DOI: 10.1016/j.ceb.2017.05.007] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Revised: 04/24/2017] [Accepted: 05/02/2017] [Indexed: 11/24/2022]
Abstract
The evidence for the importance of aberrant translation in cancer cells is overwhelming. Reflecting the wealth of data, there are excellent reviews delineating how ribosomes and initiation factors are linked to cancer [1-3], and the therapeutic strategies being devised to target them [4]. Changes in translational efficiency can engender a malignant phenotype without the need for chromatin reorganization, transcription, splicing and mRNA export [5,6]. Thus, cancer-related modulations of the translational machinery are ideally suited to allow cancer cells to respond to the various stresses encountered along the path of tumorigenesis and organism-wide dissemination [7•,8,9,10•]. Emerging findings supporting this notion are the focus of this review.
Collapse
|
30
|
Morin-Doré L, Blondin P, Vigneault C, Grand FX, Labrecque R, Sirard MA. Transcriptomic evaluation of bovine blastocysts obtained from peri-pubertal oocyte donors. Theriogenology 2017; 93:111-123. [PMID: 28257859 DOI: 10.1016/j.theriogenology.2017.01.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2016] [Revised: 12/09/2016] [Accepted: 01/03/2017] [Indexed: 12/18/2022]
Abstract
Assisted reproduction technologies (ART) and high selection pressure in the dairy industry are leading towards the use of younger females for reproduction, thereby reducing the interval between generations. This situation may have a negative impact on embryo quality, thus reducing the success rate of the procedures. This study aimed to document the effects of oocyte donor age on embryo quality, at the transcriptomic level, in order to characterize the effects of using young females for reproduction purpose. Young Holstein heifers (n = 10) were used at three different ages for ovarian stimulation protocols and oocyte collections (at 8, 11 and 14 months). All of the oocytes were fertilized in vitro with the semen of one adult bull, generating three lots of embryos per animal. Each animal was its own control for the evaluation of the effects of age. The EmbryoGENE platform was used for the assessment of gene expression patterns at the blastocyst stage. Embryos from animals at 8 vs 14 months and at 11 vs 14 months were used for microarray hybridization. Validation was done by performing RT-qPCR on seven candidate genes. Age-related contrast analysis (8 vs 14 mo and 11 vs 14 mo) identified 242 differentially expressed genes (DEGs) for the first contrast, and 296 for the second. The analysis of the molecular and biological functions of the DEGs suggests a metabolic cause to explain the differences that are observed between embryos from immature and adult subjects. The mTOR and PPAR signaling pathways, as well as the NRF2-mediated oxidative stress response pathways were among the gene expression pathways affected by donor age. In conclusion, the main differences between embryos produced at peri-pubertal ages are related to metabolic conditions resulting in a higher impact of in vitro conditions on blastocyts from younger heifers.
Collapse
Affiliation(s)
- Léonie Morin-Doré
- Centre de recherche en reproduction, développement et santé intergénérationnelle (CRDSI), Département des Sciences Animales, Faculté des Sciences de l'Agriculture et de l'Alimentation, Université Laval, Québec, Canada
| | | | | | | | | | - Marc-André Sirard
- Centre de recherche en reproduction, développement et santé intergénérationnelle (CRDSI), Département des Sciences Animales, Faculté des Sciences de l'Agriculture et de l'Alimentation, Université Laval, Québec, Canada.
| |
Collapse
|
31
|
Curran JA, Weiss B. What Is the Impact of mRNA 5' TL Heterogeneity on Translational Start Site Selection and the Mammalian Cellular Phenotype? Front Genet 2016; 7:156. [PMID: 27630668 PMCID: PMC5005323 DOI: 10.3389/fgene.2016.00156] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Accepted: 08/16/2016] [Indexed: 12/23/2022] Open
Abstract
A major determinant in the efficiency of ribosome loading onto mRNAs is the 5′ TL (transcript leader or 5′ UTR). In addition, elements within this region also impact on start site selection demonstrating that it can modulate the protein readout at both quantitative and qualitative levels. With the increasing wealth of data generated by the mining of the mammalian transcriptome, it has become evident that a genes 5′ TL is not homogeneous but actually exhibits significant heterogeneity. This arises due to the utilization of alternative promoters, and is further compounded by significant variability with regards to the precise transcriptional start sites of each (not to mention alternative splicing). Consequently, the transcript for a protein coding gene is not a unique mRNA, but in-fact a complexed quasi-species of variants whose composition may respond to the changing physiological environment of the cell. Here we examine the potential impact of these events with regards to the protein readout.
Collapse
Affiliation(s)
- Joseph A Curran
- Department of Microbiology and Molecular Medicine, Medical School, University of GenevaGeneva, Switzerland; Institute of Genetics and Genomics of Geneva, University of GenevaGeneva, Switzerland
| | - Benjamin Weiss
- Department of Microbiology and Molecular Medicine, Medical School, University of Geneva Geneva, Switzerland
| |
Collapse
|
32
|
Frydryskova K, Masek T, Borcin K, Mrvova S, Venturi V, Pospisek M. Distinct recruitment of human eIF4E isoforms to processing bodies and stress granules. BMC Mol Biol 2016; 17:21. [PMID: 27578149 PMCID: PMC5006505 DOI: 10.1186/s12867-016-0072-x] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Accepted: 08/16/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Eukaryotic translation initiation factor 4E (eIF4E) plays a pivotal role in the control of cap-dependent translation initiation, modulates the fate of specific mRNAs, occurs in processing bodies (PBs) and is required for formation of stress granules (SGs). In this study, we focused on the subcellular localization of a representative compendium of eIF4E protein isoforms, particularly on the less studied members of the human eIF4E protein family, eIF4E2 and eIF4E3. RESULTS We showed that unlike eIF4E1, its less studied isoform eIF4E3_A, encoded by human chromosome 3, localized to stress granules but not PBs upon both heat shock and arsenite stress. Furthermore, we found that eIF4E3_A interacts with human translation initiation factors eIF4G1, eIF4G3 and PABP1 in vivo and sediments into the same fractions as canonical eIF4E1 during polysome analysis in sucrose gradients. Contrary to this finding, the truncated human eIF4E3 isoform, eIF4E3_B, showed no localization to SGs and no binding to eIF4G. We also highlighted that eIF4E2 may exhibit distinct functions under different stresses as it readily localizes to P-bodies during arsenite and heat stresses, whereas it is redirected to stress granules only upon heat shock. We extended our study to a number of protein variants, arising from alternative mRNA splicing, of each of the three eIF4E isoforms. Our results surprisingly uncovered differences in the ability of eIF4E1_1 and eIF4E1_3 to form stress granules in response to cellular stresses. CONCLUSION Our comparison of all three human eIF4E isoforms and their protein variants enriches the intriguing spectrum of roles attributed to the eukaryotic initiation translation factors of the 4E family, which exhibit a distinctive localization within different RNA granules under different stresses. The localization of eIF4E3_A to stress granules, but not to processing bodies, along with its binding to eIF4G and PABP1 suggests a role of human eIF4E3_A in translation initiation rather than its involvement in a translational repression and mRNA decay and turnover. The localization of eIF4E2 to stress granules under heat shock but not arsenite stress indicates its distinct function in cellular response to these stresses and points to the variable protein content of SGs as a consequence of different stress insults.
Collapse
Affiliation(s)
- Klara Frydryskova
- Laboratory of RNA Biochemistry, Department of Genetics and Microbiology, Faculty of Science, Charles University in Prague, Viničná 5, 128 00, Prague 2, Czech Republic
| | - Tomas Masek
- Laboratory of RNA Biochemistry, Department of Genetics and Microbiology, Faculty of Science, Charles University in Prague, Viničná 5, 128 00, Prague 2, Czech Republic.
| | - Katerina Borcin
- Laboratory of RNA Biochemistry, Department of Genetics and Microbiology, Faculty of Science, Charles University in Prague, Viničná 5, 128 00, Prague 2, Czech Republic
| | - Silvia Mrvova
- Laboratory of RNA Biochemistry, Department of Genetics and Microbiology, Faculty of Science, Charles University in Prague, Viničná 5, 128 00, Prague 2, Czech Republic
| | - Veronica Venturi
- Laboratory of RNA Biochemistry, Department of Genetics and Microbiology, Faculty of Science, Charles University in Prague, Viničná 5, 128 00, Prague 2, Czech Republic.,Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Dr. Aiguader 88, 08003, Barcelona, Spain
| | - Martin Pospisek
- Laboratory of RNA Biochemistry, Department of Genetics and Microbiology, Faculty of Science, Charles University in Prague, Viničná 5, 128 00, Prague 2, Czech Republic.
| |
Collapse
|
33
|
Cressey PB, Eskandari A, Bruno PM, Lu C, Hemann MT, Suntharalingam K. The Potent Inhibitory Effect of a Naproxen-Appended Cobalt(III)-Cyclam Complex on Cancer Stem Cells. Chembiochem 2016; 17:1713-8. [PMID: 27377813 DOI: 10.1002/cbic.201600368] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Indexed: 12/31/2022]
Abstract
We report the potency against cancer stem cells (CSCs) of a new cobalt(III)-cyclam complex (1) that bears the nonsteroidal anti-inflammatory drug, naproxen. The complex displays selective potency for breast CSC-enriched HMLER-shEcad cells over breast CSC-depleted HMLER cells. Additionally, it inhibited the formation of three-dimensional tumour-like mammospheres, and reduced their viability to a greater extent than clinically used breast cancer drugs (vinorelbine, cisplatin and paclitaxel). The anti-mammosphere potency of 1 was enhanced under hypoxia-mimicking conditions. Detailed mechanistic studies revealed that DNA damage and cyclooxygenase-2 (COX-2) inhibition contribute to the cytotoxic mechanism of 1. To the best of our knowledge, 1 is the first cobalt-containing compound to show selective potency for CSCs over bulk cancer cells.
Collapse
Affiliation(s)
- Paul B Cressey
- Department of Chemistry, King's College London, Britannia House, 7 Trinity Street, London, SE1 1DB, UK
| | - Arvin Eskandari
- Department of Chemistry, King's College London, Britannia House, 7 Trinity Street, London, SE1 1DB, UK
| | - Peter M Bruno
- The Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Building 76, 500 Main Street, Cambridge, MA, 02139, USA
| | - Chunxin Lu
- Department of Chemistry, King's College London, Britannia House, 7 Trinity Street, London, SE1 1DB, UK
| | - Michael T Hemann
- The Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Building 76, 500 Main Street, Cambridge, MA, 02139, USA
| | | |
Collapse
|
34
|
Abstract
The past several years have seen dramatic leaps in our understanding of how gene expression is rewired at the translation level during tumorigenesis to support the transformed phenotype. This work has been driven by an explosion in technological advances and is revealing previously unimagined regulatory mechanisms that dictate functional expression of the cancer genome. In this Review we discuss emerging trends and exciting new discoveries that reveal how this translational circuitry contributes to specific aspects of tumorigenesis and cancer cell function, with a particular focus on recent insights into the role of translational control in the adaptive response to oncogenic stress conditions.
Collapse
Affiliation(s)
- Morgan L Truitt
- Department of Urology, University of California, San Francisco
- Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, California 94158, USA
| | - Davide Ruggero
- Department of Urology, University of California, San Francisco
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco
- Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, California 94158, USA
| |
Collapse
|
35
|
Timpano S, Uniacke J. Human Cells Cultured under Physiological Oxygen Utilize Two Cap-binding Proteins to recruit Distinct mRNAs for Translation. J Biol Chem 2016; 291:10772-82. [PMID: 27002144 DOI: 10.1074/jbc.m116.717363] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Indexed: 11/06/2022] Open
Abstract
Translation initiation is a focal point of translational control and requires the binding of eIF4E to the 5' cap of mRNA. Under conditions of extreme oxygen depletion (hypoxia), human cells repress eIF4E and switch to an alternative cap-dependent translation mediated by a homolog of eIF4E, eIF4E2. This homolog forms a complex with the oxygen-regulated hypoxia-inducible factor 2α and can escape translation repression. This complex mediates cap-dependent translation under cell culture conditions of 1% oxygen (to mimic tumor microenvironments), whereas eIF4E mediates cap-dependent translation at 21% oxygen (ambient air). However, emerging evidence suggests that culturing cells in ambient air, or "normoxia," is far from physiological or "normal." In fact, oxygen in human tissues ranges from 1-11% or "physioxia." Here we show that two distinct modes of cap-dependent translation initiation are active during physioxia and act on separate pools of mRNAs. The oxygen-dependent activities of eIF4E and eIF4E2 are elucidated by observing their polysome association and the status of mammalian target of rapamycin complex 1 (eIF4E-dependent) or hypoxia-inducible factor 2α expression (eIF4E2-dependent). We have identified oxygen conditions where eIF4E is the dominant cap-binding protein (21% normoxia or standard cell culture conditions), where eIF4E2 is the dominant cap-binding protein (1% hypoxia or ischemic diseases and cancerous tumors), and where both cap-binding proteins act simultaneously to initiate the translation of distinct mRNAs (1-11% physioxia or during development and stem cell differentiation). These data suggest that the physioxic proteome is generated by initiating translation of mRNAs via two distinct but complementary cap-binding proteins.
Collapse
Affiliation(s)
- Sara Timpano
- From the Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
| | - James Uniacke
- From the Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
| |
Collapse
|
36
|
Ho JJD, Wang M, Audas TE, Kwon D, Carlsson SK, Timpano S, Evagelou SL, Brothers S, Gonzalgo ML, Krieger JR, Chen S, Uniacke J, Lee S. Systemic Reprogramming of Translation Efficiencies on Oxygen Stimulus. Cell Rep 2016; 14:1293-1300. [PMID: 26854219 DOI: 10.1016/j.celrep.2016.01.036] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Revised: 10/29/2015] [Accepted: 01/08/2016] [Indexed: 10/22/2022] Open
Abstract
Protein concentrations evolve under greater evolutionary constraint than mRNA levels. Translation efficiency of mRNA represents the chief determinant of basal protein concentrations. This raises a fundamental question of how mRNA and protein levels are coordinated in dynamic systems responding to physiological stimuli. This report examines the contributions of mRNA abundance and translation efficiency to protein output in cells responding to oxygen stimulus. We show that changes in translation efficiencies, and not mRNA levels, represent the major mechanism governing cellular responses to [O2] perturbations. Two distinct cap-dependent protein synthesis machineries select mRNAs for translation: the normoxic eIF4F and the hypoxic eIF4F(H). O2-dependent remodeling of translation efficiencies enables cells to produce adaptive translatomes from preexisting mRNA pools. Differences in mRNA expression observed under different [O2] are likely neutral, given that they occur during evolution. We propose that mRNAs contain translation efficiency determinants for their triage by the translation apparatus on [O2] stimulus.
Collapse
Affiliation(s)
- J J David Ho
- Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, FL 31336, USA; Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, FL 31336, USA
| | - Miling Wang
- Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, FL 31336, USA; Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, FL 31336, USA
| | - Timothy E Audas
- Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, FL 31336, USA; Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, FL 31336, USA
| | - Deukwoo Kwon
- Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, FL 31336, USA; Biostatistics and Bioinformatics Core, Miller School of Medicine, University of Miami, Miami, FL 31336, USA
| | - Steven K Carlsson
- Center for Therapeutic Innovation, Miller School of Medicine, University of Miami, Miami, FL 31336, USA
| | - Sara Timpano
- Department of Molecular and Cellular Biology, College of Biological Science, University of Guelph, Guelph, ON N1G 2W1, Canada
| | - Sonia L Evagelou
- Department of Molecular and Cellular Biology, College of Biological Science, University of Guelph, Guelph, ON N1G 2W1, Canada
| | - Shaun Brothers
- Center for Therapeutic Innovation, Miller School of Medicine, University of Miami, Miami, FL 31336, USA; Department of Psychiatry, Miller School of Medicine, University of Miami, Miami, FL 31336, USA
| | - Mark L Gonzalgo
- Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, FL 31336, USA; Department of Urology, Miller School of Medicine, University of Miami, Miami, FL 31336, USA
| | - Jonathan R Krieger
- SPARC BioCentre, The Hospital for Sick Children, Toronto, ON M5G 1X8, Canada
| | - Steven Chen
- Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, FL 31336, USA; Biostatistics and Bioinformatics Core, Miller School of Medicine, University of Miami, Miami, FL 31336, USA; Division of Biostatistics, Department of Public Health Sciences, Miller School of Medicine, University of Miami, Miami, FL 31336, USA
| | - James Uniacke
- Department of Molecular and Cellular Biology, College of Biological Science, University of Guelph, Guelph, ON N1G 2W1, Canada
| | - Stephen Lee
- Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, FL 31336, USA; Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, FL 31336, USA; Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada.
| |
Collapse
|
37
|
Yi T, Kabha E, Papadopoulos E, Wagner G. 4EGI-1 targets breast cancer stem cells by selective inhibition of translation that persists in CSC maintenance, proliferation and metastasis. Oncotarget 2015; 5:6028-37. [PMID: 25115391 PMCID: PMC4171610 DOI: 10.18632/oncotarget.2112] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Cancer death is a leading cause of global mortality. An estimated 14.1 million new cancer cases and 8.2 million cancer deaths occurred worldwide in 2012 alone. Cancer stem cells (CSCs) within tumors are essential for tumor metastasis and reoccurrence, the key factors of cancer lethality. Here we report that 4EGI-1, an inhibitor of the interaction between translation initiation factors eIF4E1 and eIF4G1 effectively inhibits breast CSCs through selectively reducing translation persistent in breast CSCs. Translation initiation factor eIF4E1 is significantly enhanced in breast CSCs in comparison to non-CSC breast cancer cells. 4EGI-1 presents increased cytotoxicity to breast CSCs compared to non-CSC breast cancer cells. 4EGI-1 promotes breast CSC differentiation and represses breast CSC induced tube-like structure formation of human umbilical vein endothelial cells (HUVECs). 4EGI-1 isomers suppress breast CSC tumorangiogenesis and tumor growth in vivo. In addition, 4EGI-1 decreases proliferation in and induces apoptosis into breast CSC tumor cells. Furthermore, 4EGI-1 selectively inhibits translation of mRNAs encoding NANOG, OCT4, CXCR4, c-MYC and VEGF in breast CSC tumors. Our study demonstrated that 4EGI-1 targets breast CSCs through selective inhibition of translation critical for breast CSCs, suggesting that selective translation initiation interference might be an avenue targeting CSCs within tumors.
Collapse
Affiliation(s)
- Tingfang Yi
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA
| | - Eihab Kabha
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA
| | - Evangelos Papadopoulos
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA
| | - Gerhard Wagner
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA
| |
Collapse
|
38
|
Arnason T, Harkness T. Development, Maintenance, and Reversal of Multiple Drug Resistance: At the Crossroads of TFPI1, ABC Transporters, and HIF1. Cancers (Basel) 2015; 7:2063-82. [PMID: 26501324 PMCID: PMC4695877 DOI: 10.3390/cancers7040877] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2015] [Accepted: 10/10/2015] [Indexed: 12/21/2022] Open
Abstract
Early detection and improved therapies for many cancers are enhancing survival rates. Although many cytotoxic therapies are approved for aggressive or metastatic cancer; response rates are low and acquisition of de novo resistance is virtually universal. For decades; chemotherapeutic treatments for cancer have included anthracyclines such as Doxorubicin (DOX); and its use in aggressive tumors appears to remain a viable option; but drug resistance arises against DOX; as for all other classes of compounds. Our recent work suggests the anticoagulant protein Tissue Factor Pathway Inhibitor 1α (TFPI1α) plays a role in driving the development of multiple drug resistance (MDR); but not maintenance; of the MDR state. Other factors; such as the ABC transporter drug efflux pumps MDR-1/P-gp (ABCB1) and BCRP (ABCG2); are required for MDR maintenance; as well as development. The patient population struggling with therapeutic resistance specifically requires novel treatment options to resensitize these tumor cells to therapy. In this review we discuss the development, maintenance, and reversal of MDR as three distinct phases of cancer biology. Possible means to exploit these stages to reverse MDR will be explored. Early molecular detection of MDR cancers before clinical failure has the potential to offer new approaches to fighting MDR cancer.
Collapse
Affiliation(s)
- Terra Arnason
- Department of Medicine, University of Saskatchewan, Saskatoon, SK S7N 0W8, Canada
- Correspondence: ; Tel.:+1-306-844-1119; Fax: +1-306-844-1512
| | - Troy Harkness
- Department of Anatomy and Cell Biology, University of Saskatchewan, Saskatoon, SK S7N 0W8, Canada;
| |
Collapse
|
39
|
Staudacher JJ, Naarmann-de Vries IS, Ujvari SJ, Klinger B, Kasim M, Benko E, Ostareck-Lederer A, Ostareck DH, Bondke Persson A, Lorenzen S, Meier JC, Blüthgen N, Persson PB, Henrion-Caude A, Mrowka R, Fähling M. Hypoxia-induced gene expression results from selective mRNA partitioning to the endoplasmic reticulum. Nucleic Acids Res 2015; 43:3219-36. [PMID: 25753659 PMCID: PMC4381074 DOI: 10.1093/nar/gkv167] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Accepted: 02/21/2015] [Indexed: 01/01/2023] Open
Abstract
Protein synthesis is a primary energy-consuming process in the cell. Therefore, under hypoxic conditions, rapid inhibition of global mRNA translation represents a major protective strategy to maintain energy metabolism. How some mRNAs, especially those that encode crucial survival factors, continue to be efficiently translated in hypoxia is not completely understood. By comparing specific transcript levels in ribonucleoprotein complexes, cytoplasmic polysomes and endoplasmic reticulum (ER)-bound ribosomes, we show that the synthesis of proteins encoded by hypoxia marker genes is favoured at the ER in hypoxia. Gene expression profiling revealed that transcripts particularly increased by the HIF-1 transcription factor network show hypoxia-induced enrichment at the ER. We found that mRNAs favourably translated at the ER have higher conservation scores for both the 5'- and 3'-untranslated regions (UTRs) and contain less upstream initiation codons (uAUGs), indicating the significance of these sequence elements for sustained mRNA translation under hypoxic conditions. Furthermore, we found enrichment of specific cis-elements in mRNA 5'- as well as 3'-UTRs that mediate transcript localization to the ER in hypoxia. We conclude that transcriptome partitioning between the cytoplasm and the ER permits selective mRNA translation under conditions of energy shortage.
Collapse
Affiliation(s)
- Jonas J Staudacher
- Charité - Universitätsmedizin Berlin, Institut für Vegetative Physiologie, Charitéplatz 1, D-10117 Berlin, Germany
| | - Isabel S Naarmann-de Vries
- University Hospital Aachen, RWTH Aachen University, Department of Intensive and Intermediate Care, Experimental Research Unit, D-52074 Aachen, Germany
| | - Stefanie J Ujvari
- Charité - Universitätsmedizin Berlin, Institut für Vegetative Physiologie, Charitéplatz 1, D-10117 Berlin, Germany
| | - Bertram Klinger
- Humboldt Universität zu Berlin, Institut für Theoretische Biologie, D-10115 Berlin, Germany Charité - Universitätsmedizin Berlin, Institut für Pathologie, D-10117 Berlin, Germany
| | - Mumtaz Kasim
- Charité - Universitätsmedizin Berlin, Institut für Vegetative Physiologie, Charitéplatz 1, D-10117 Berlin, Germany
| | - Edgar Benko
- Charité - Universitätsmedizin Berlin, Institut für Vegetative Physiologie, Charitéplatz 1, D-10117 Berlin, Germany
| | - Antje Ostareck-Lederer
- University Hospital Aachen, RWTH Aachen University, Department of Intensive and Intermediate Care, Experimental Research Unit, D-52074 Aachen, Germany
| | - Dirk H Ostareck
- University Hospital Aachen, RWTH Aachen University, Department of Intensive and Intermediate Care, Experimental Research Unit, D-52074 Aachen, Germany
| | - Anja Bondke Persson
- Charité - Universitätsmedizin Berlin, Institut für Vegetative Physiologie, Charitéplatz 1, D-10117 Berlin, Germany
| | - Stephan Lorenzen
- Universitätsklinikum Jena, Klinik für Innere Medizin III, AG Experimentelle Nephrologie, D-07743 Jena, Germany
| | - Jochen C Meier
- Max Delbrück Center for Molecular Medicine, RNA Editing and Hyperexcitability Disorders Helmholtz Group, D-13125 Berlin, Germany TU Braunschweig, Zoological Institute, Division of Cell Physiology, D-38106 Braunschweig, Germany
| | - Nils Blüthgen
- Humboldt Universität zu Berlin, Institut für Theoretische Biologie, D-10115 Berlin, Germany Charité - Universitätsmedizin Berlin, Institut für Pathologie, D-10117 Berlin, Germany
| | - Pontus B Persson
- Charité - Universitätsmedizin Berlin, Institut für Vegetative Physiologie, Charitéplatz 1, D-10117 Berlin, Germany
| | - Alexandra Henrion-Caude
- Hôpital Necker-Enfants Malades, Université Paris Descartes, Institut National de la Santé et de la Recherche Médicale (INSERM) UMR1163 and Imagine Foundation, 75015 Paris, France
| | - Ralf Mrowka
- Universitätsklinikum Jena, Klinik für Innere Medizin III, AG Experimentelle Nephrologie, D-07743 Jena, Germany
| | - Michael Fähling
- Charité - Universitätsmedizin Berlin, Institut für Vegetative Physiologie, Charitéplatz 1, D-10117 Berlin, Germany
| |
Collapse
|
40
|
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.
Collapse
|
41
|
de la Parra C, Borrero-Garcia LD, Cruz-Collazo A, Schneider RJ, Dharmawardhane S. Equol, an isoflavone metabolite, regulates cancer cell viability and protein synthesis initiation via c-Myc and eIF4G. J Biol Chem 2015; 290:6047-57. [PMID: 25593313 PMCID: PMC4358247 DOI: 10.1074/jbc.m114.617415] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2014] [Revised: 12/30/2014] [Indexed: 12/28/2022] Open
Abstract
Epidemiological studies implicate dietary soy isoflavones as breast cancer preventives, especially due to their anti-estrogenic properties. However, soy isoflavones may also have a role in promoting breast cancer, which has yet to be clarified. We previously reported that equol, a metabolite of the soy isoflavone daidzein, may advance breast cancer potential via up-regulation of the eukaryotic initiation factor 4GI (eIF4GI). In estrogen receptor negative (ER-) metastatic breast cancer cells, equol induced elevated levels of eIF4G, which were associated with increased cell viability and the selective translation of mRNAs that use non-canonical means of initiation, including internal ribosome entry site (IRES), ribosome shunting, and eIF4G enhancers. These mRNAs typically code for oncogenic, survival, and cell stress molecules. Among those mRNAs translationally increased by equol was the oncogene and eIF4G enhancer, c-Myc. Here we report that siRNA-mediated knockdown of c-Myc abrogates the increase in cancer cell viability and mammosphere formation by equol, and results in a significant down-regulation of eIF4GI (the major eIF4G isoform), as well as reduces levels of some, but not all, proteins encoded by mRNAs that are translationally stimulated by equol treatment. Knockdown of eIF4GI also markedly reduces an equol-mediated increase in IRES-dependent mRNA translation and the expression of specific oncogenic proteins. However, eIF4GI knockdown did not reciprocally affect c-Myc levels or cell viability. This study therefore implicates c-Myc as a potential regulator of the cancer-promoting effects of equol via up-regulation of eIF4GI and selective initiation of translation on mRNAs that utilize non-canonical initiation, including certain oncogenes.
Collapse
Affiliation(s)
- Columba de la Parra
- From the Department of Biochemistry, School of Medicine, University of Puerto Rico, Medical Sciences Campus, San Juan, Puerto Rico 00936 and Department of Microbiology and Radiation Oncology, NYU Cancer Institute, New York University School of Medicine, New York, New York 10016
| | - Luis D Borrero-Garcia
- From the Department of Biochemistry, School of Medicine, University of Puerto Rico, Medical Sciences Campus, San Juan, Puerto Rico 00936 and
| | - Ailed Cruz-Collazo
- From the Department of Biochemistry, School of Medicine, University of Puerto Rico, Medical Sciences Campus, San Juan, Puerto Rico 00936 and
| | - Robert J Schneider
- Department of Microbiology and Radiation Oncology, NYU Cancer Institute, New York University School of Medicine, New York, New York 10016
| | - Suranganie Dharmawardhane
- From the Department of Biochemistry, School of Medicine, University of Puerto Rico, Medical Sciences Campus, San Juan, Puerto Rico 00936 and
| |
Collapse
|
42
|
Diab-Assaf M, Abou-khouzam R, Saadallah-Zeidan N, Habib K, Bitar N, Karam W, Liagre B, Harakeh S, Azar R. Expression of eukaryotic initiation factor 4E and 4E binding protein 1 in colorectal carcinogenesis. INTERNATIONAL JOURNAL OF CLINICAL AND EXPERIMENTAL PATHOLOGY 2015; 8:404-413. [PMID: 25755728 PMCID: PMC4348849] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 11/03/2014] [Accepted: 12/22/2014] [Indexed: 06/04/2023]
Abstract
Cap dependent translation is mainly regulated at the level of the eukaryotic initiation factor 4E (eIF4E), the activity of which is controlled by phosphorylation and sequestration by its well established regulator, 4E binding protein 1 (4E-BP1). Both eIF4E and 4E-BP1 have been shown to be involved in the malignant progression of multiple human cancers, including colorectal cancer. However, the data on determining the expression of eIF4E, 4E-BP1 and their phosphorylated forms simultaneously in a single patient with colorectal cancer is lacking. Therefore the aim of our study was to explore the roles of these factors in colorectal carcinogenesis by immunohistostaining colorectal tissues (normal, low grade adenoma, high grade adenoma, and adenocarcinoma). Our results showed that the expression levels of eIF4E increased steadily as the cancer progressed from the case of benign dysplasia to an adenocarcinoma; all the while maintaining an unphosphorylated form. On the other hand, total expression levels of 4E-BP1 increased only in the premalignant state of the disease and decreased (but highly phosphorylated or inactivated) or abolished upon malignancy. Taken together, our findings suggest that strong correlations exist between the expression of eIF4E (not p-eIF4E) and tumor grade providing evidence that eIF4E expression plays a pivotal role in the malignant progression of colorectal cancer. Moreover, 4E-BP1 showed a bi-phasic level of expression during carcinogenesis, which is expressed only in hyperplasic or dysplastic tissues as an endogenous tumor suppressor molecule.
Collapse
Affiliation(s)
- Mona Diab-Assaf
- Molecular Tumorigenesis and Anticancer Pharmacology, EDST, Lebanese UniversityHadath, Lebanon
| | - Raefa Abou-khouzam
- Molecular Tumorigenesis and Anticancer Pharmacology, EDST, Lebanese UniversityHadath, Lebanon
| | - Nina Saadallah-Zeidan
- Molecular Tumorigenesis and Anticancer Pharmacology, EDST, Lebanese UniversityHadath, Lebanon
| | - Khaled Habib
- Specialized Medical LaboratoryAl-Mazraa, Beirut, Lebanon
| | - Nizar Bitar
- Faculty of Medicine, Lebanese UniversityHadath, Lebanon
| | - Walid Karam
- Molecular Tumorigenesis and Anticancer Pharmacology, EDST, Lebanese UniversityHadath, Lebanon
| | - Bertrand Liagre
- Biochemistry and Molecular Biology Laboratory, Faculty of Pharmacy, University of LimogesFR 3503 GEIST, EA1069, GDR CNRS 3049, Limoges, France
| | - Steve Harakeh
- Special Infectious Agents Unit, King Fahd Medical Research Center, King Abdulaziz UniversityKingdom of Saudi Arabia
| | - Rania Azar
- Molecular Tumorigenesis and Anticancer Pharmacology, EDST, Lebanese UniversityHadath, Lebanon
| |
Collapse
|
43
|
MNKs act as a regulatory switch for eIF4E1 and eIF4E3 driven mRNA translation in DLBCL. Nat Commun 2014; 5:5413. [PMID: 25403230 PMCID: PMC4238046 DOI: 10.1038/ncomms6413] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2014] [Accepted: 09/29/2014] [Indexed: 02/08/2023] Open
Abstract
The phosphorylation of eIF4E1 at serine 209 by MNK1 or MNK2 has been shown to initiate oncogenic mRNA translation, a process that favours cancer development and maintenance. Here, we interrogate the MNK-eIF4E axis in diffuse large B-cell lymphoma (DLBCL) and show a distinct distribution of MNK1 and MNK2 in germinal centre B-cell (GCB) and activated B-cell (ABC) DLBCL. Despite displaying a differential distribution in GCB and ABC, both MNKs functionally complement each other to sustain cell survival. MNK inhibition ablates eIF4E1 phosphorylation and concurrently enhances eIF4E3 expression. Loss of MNK protein itself downregulates total eIF4E1 protein level by reducing eIF4E1 mRNA polysomal loading without affecting total mRNA level or stability. Enhanced eIF4E3 expression marginally suppresses eIF4E1-driven translation but exhibits a unique translatome that unveils a novel role for eIF4E3 in translation initiation. We propose that MNKs can modulate oncogenic translation by regulating eIF4E1-eIF4E3 levels and activity in DLBCL. Diffuse large B-cell lymphoma (DLBCL) is a highly aggressive and heterogeneous type of non-Hodgkin’s lymphoma. Here the authors demonstrate that the differential regulation of eIF4E1 and eIF4E3 by the MAPK-interacting kinases is involved in DLBCL aetiology through modification of the cellular translatome.
Collapse
|
44
|
Leprivier G, Rotblat B, Khan D, Jan E, Sorensen PH. Stress-mediated translational control in cancer cells. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2014; 1849:845-60. [PMID: 25464034 DOI: 10.1016/j.bbagrm.2014.11.002] [Citation(s) in RCA: 73] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 08/22/2014] [Revised: 10/31/2014] [Accepted: 11/04/2014] [Indexed: 12/22/2022]
Abstract
Tumor cells are continually subjected to diverse stress conditions of the tumor microenvironment, including hypoxia, nutrient deprivation, and oxidative or genotoxic stress. Tumor cells must evolve adaptive mechanisms to survive these conditions to ultimately drive tumor progression. Tight control of mRNA translation is critical for this response and the adaptation of tumor cells to such stress forms. This proceeds though a translational reprogramming process which restrains overall translation activity to preserve energy and nutrients, but which also stimulates the selective synthesis of major stress adaptor proteins. Here we present the different regulatory signaling pathways which coordinate mRNA translation in the response to different stress forms, including those regulating eIF2α, mTORC1 and eEF2K, and we explain how tumor cells hijack these pathways for survival under stress. Finally, mechanisms for selective mRNA translation under stress, including the utilization of upstream open reading frames (uORFs) and internal ribosome entry sites (IRESes) are discussed in the context of cell stress. This article is part of a Special Issue entitled: Translation and Cancer.
Collapse
Affiliation(s)
- Gabriel Leprivier
- Department of Molecular Oncology, British Columbia Cancer Research Centre, Vancouver, British Columbia V5Z 1L4, Canada; Department of Pathology, University of British Columbia, Vancouver, British Columbia V6T 2B5, Canada
| | - Barak Rotblat
- Department of Life Science, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel
| | - Debjit Khan
- Department of Molecular Oncology, British Columbia Cancer Research Centre, Vancouver, British Columbia V5Z 1L4, Canada; Department of Pathology, University of British Columbia, Vancouver, British Columbia V6T 2B5, Canada
| | - Eric Jan
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia V6T1Z3, Canada
| | - Poul H Sorensen
- Department of Molecular Oncology, British Columbia Cancer Research Centre, Vancouver, British Columbia V5Z 1L4, Canada; Department of Pathology, University of British Columbia, Vancouver, British Columbia V6T 2B5, Canada.
| |
Collapse
|
45
|
Structure of the eukaryotic translation initiation factor eIF4E in complex with 4EGI-1 reveals an allosteric mechanism for dissociating eIF4G. Proc Natl Acad Sci U S A 2014; 111:E3187-95. [PMID: 25049413 DOI: 10.1073/pnas.1410250111] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The interaction of the eukaryotic translation initiation factor eIF4E with the initiation factor eIF4G recruits the 40S ribosomal particle to the 5' end of mRNAs, facilitates scanning to the AUG start codon, and is crucial for eukaryotic translation of nearly all genes. Efficient recruitment of the 40S particle is particularly important for translation of mRNAs encoding oncoproteins and growth-promoting factors, which often harbor complex 5' UTRs and require efficient initiation. Thus, inhibiting the eIF4E/eIF4G interaction has emerged as a previously unpursued route for developing anticancer agents. Indeed, we discovered small-molecule inhibitors of this eIF4E/eIF4G interaction (4EGIs) that inhibit translation initiation both in vitro and in vivo and were used successfully in numerous cancer-biology and neurobiology studies. However, their detailed molecular mechanism of action has remained elusive. Here, we show that the eIF4E/eIF4G inhibitor 4EGI-1 acts allosterically by binding to a site on eIF4E distant from the eIF4G binding epitope. Data from NMR mapping and high-resolution crystal structures are congruent with this mechanism, where 4EGI-1 attaches to a hydrophobic pocket of eIF4E between β-sheet2 (L60-T68) and α-helix1 (E69-N77), causing localized conformational changes mainly in the H78-L85 region. It acts by unfolding a short 310-helix (S82-L85) while extending α-helix1 by one turn (H78-S82). This unusual helix rearrangement has not been seen in any previous eIF4E structure and reveals elements of an allosteric inhibition mechanism leading to the dislocation of eIF4G from eIF4E.
Collapse
|
46
|
Pettersson F, del Rincon SV, Miller WH. Eukaryotic translation initiation factor 4E as a novel therapeutic target in hematological malignancies and beyond. Expert Opin Ther Targets 2014; 18:1035-48. [DOI: 10.1517/14728222.2014.937426] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
|
47
|
Lee S, Goldfinger LE. RLIP76 regulates HIF-1 activity, VEGF expression and secretion in tumor cells, and secretome transactivation of endothelial cells. FASEB J 2014; 28:4158-68. [PMID: 24928198 DOI: 10.1096/fj.14-255711] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2014] [Accepted: 06/02/2014] [Indexed: 02/02/2023]
Abstract
This study was undertaken to reveal the mechanisms by which RLIP76 regulates endothelial cell angiogenic responses. RLIP76 is an effector of the angiogenic modulator, R-Ras. RLIP76 is overexpressed in many tumors, required for tumor angiogenesis, and blockade of RLIP76 results in tumor regression in multiple models. We report here that RLIP76 was required for expression and secretion of vascular endothelial growth factor (VEGF) in carcinoma and melanoma cells. Conditioned medium derived from RLIP76-depleted tumor cells, but not control knockdown cells, could not stimulate proliferation, migration, or Matrigel cord formation in endothelial cell cultures, which indicates that RLIP76 regulates angiogenic components of the tumor cell secretome. Recombinant VEGF added to conditioned medium from RLIP76-knockdown tumor cells restored these endothelial cell functions. Transcriptional activity of hypoxia-inducible factor 1 (HIF-1), which drives VEGF expression, was blocked in RLIP76-depleted tumor cells. RLIP76 was required for PI3-kinase activation, known to regulate HIF-1, in these cells. However, HIF-1α expression and nuclear localization were unaffected by RLIP76 knockdown, which suggests that RLIP76 regulates HIF-1 at the functional level. Thus, RLIP76 regulates tumor cell transactivation of endothelial cells via control of VEGF expression and secretion, providing a new important link in the mechanism of tumor cell induction of angiogenesis.
Collapse
Affiliation(s)
- Seunghyung Lee
- Department of Anatomy and Cell Biology, Sol Sherry Thrombosis Research Center, Temple University School of Medicine, Philadelphia, Pennsylvania, USA; and
| | - Lawrence E Goldfinger
- Department of Anatomy and Cell Biology, Sol Sherry Thrombosis Research Center, Temple University School of Medicine, Philadelphia, Pennsylvania, USA; and Cancer Biology Program, Fox Chase Cancer Center, Philadelphia, Pennsylvania, USA
| |
Collapse
|
48
|
Uniacke J, Perera JK, Lachance G, Francisco CB, Lee S. Cancer cells exploit eIF4E2-directed synthesis of hypoxia response proteins to drive tumor progression. Cancer Res 2014; 74:1379-89. [PMID: 24408918 DOI: 10.1158/0008-5472.can-13-2278] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Human tumors display considerable diversity in their genetic makeup but share common physiologic attributes such as a hypoxic microenvironment that contribute to the malignant phenotype. Hypoxic cells switch from eukaryotic initiation factor 4E (eIF4E) to eIF4E2 cap-dependent translation to synthesize a portion of their proteins. Here, we show that genetically distinct human cancer cells exploit eIF4E2-directed protein synthesis to form cellular masses larger than approximately 0.15 mm, the diffusion limit of oxygen. Cancer cells depleted of eIF4E2 are indistinguishable from control cells under normoxic conditions, but are unable to survive and proliferate in low oxygen conditions. Activation of eIF4E2-directed translation is essential for cancer cells to form a hypoxic tumor core in in vitro spheroids and to form detectable tumors in in vivo xenograft assays. In contrast, the eIF4E-directed protein synthesis pathway alone cannot sustain cellular adaptation to hypoxia in vitro or confer tumorigenic potential in xenograft assays. These data demonstrate that the phenotypic expression of the cancer genome requires translation by the eIF4E2-directed hypoxic protein synthesis machinery.
Collapse
Affiliation(s)
- James Uniacke
- Authors' Affiliation: Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | | | | | | | | |
Collapse
|
49
|
Morfoisse F, Kuchnio A, Frainay C, Gomez-Brouchet A, Delisle MB, Marzi S, Helfer AC, Hantelys F, Pujol F, Guillermet-Guibert J, Bousquet C, Dewerchin M, Pyronnet S, Prats AC, Carmeliet P, Garmy-Susini B. Hypoxia induces VEGF-C expression in metastatic tumor cells via a HIF-1α-independent translation-mediated mechanism. Cell Rep 2014; 6:155-67. [PMID: 24388748 DOI: 10.1016/j.celrep.2013.12.011] [Citation(s) in RCA: 93] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2013] [Revised: 10/28/2013] [Accepted: 12/06/2013] [Indexed: 01/04/2023] Open
Abstract
Various tumors metastasize via lymph vessels and lymph nodes to distant organs. Even though tumors are hypoxic, the mechanisms of how hypoxia regulates lymphangiogenesis remain poorly characterized. Here, we show that hypoxia reduced vascular endothelial growth factor C (VEGF-C) transcription and cap-dependent translation via the upregulation of hypophosphorylated 4E-binding protein 1 (4E-BP1). However, initiation of VEGF-C translation was induced by hypoxia through an internal ribosome entry site (IRES)-dependent mechanism. IRES-dependent VEGF-C translation was independent of hypoxia-inducible factor 1α (HIF-1α) signaling. Notably, the VEGF-C IRES activity was higher in metastasizing tumor cells in lymph nodes than in primary tumors, most likely because lymph vessels in these lymph nodes were severely hypoxic. Overall, this transcription-independent but translation-dependent upregulation of VEGF-C in hypoxia stimulates lymphangiogenesis in tumors and lymph nodes and may contribute to lymphatic metastasis.
Collapse
Affiliation(s)
- Florent Morfoisse
- Inserm, U1037, 31432 Toulouse, France; Université de Toulouse, UPS, Cancer Research Center of Toulouse, Equipe Labellisee Ligue Contre le Cancer and Laboratoire d'Excellence Toulouse Cancer, 31432 Toulouse, France
| | - Anna Kuchnio
- Vesalius Research Center, VIB, University of Leuven, 3000 Leuven, Belgium
| | - Clement Frainay
- Inserm, U1037, 31432 Toulouse, France; Université de Toulouse, UPS, Cancer Research Center of Toulouse, Equipe Labellisee Ligue Contre le Cancer and Laboratoire d'Excellence Toulouse Cancer, 31432 Toulouse, France
| | - Anne Gomez-Brouchet
- Inserm, U1037, 31432 Toulouse, France; Université de Toulouse, UPS, Cancer Research Center of Toulouse, Equipe Labellisee Ligue Contre le Cancer and Laboratoire d'Excellence Toulouse Cancer, 31432 Toulouse, France
| | - Marie-Bernadette Delisle
- Inserm, U1037, 31432 Toulouse, France; Université de Toulouse, UPS, Cancer Research Center of Toulouse, Equipe Labellisee Ligue Contre le Cancer and Laboratoire d'Excellence Toulouse Cancer, 31432 Toulouse, France
| | - Stefano Marzi
- UPR 9002 CNRS-ARN, Université De Strasbourg, IBMC, 67084 Strasbourg, France
| | | | - Fransky Hantelys
- Université de Toulouse, UPS, TRADGENE, EA4554, 31432 Toulouse, France
| | - Francoise Pujol
- Université de Toulouse, UPS, TRADGENE, EA4554, 31432 Toulouse, France
| | - Julie Guillermet-Guibert
- Inserm, U1037, 31432 Toulouse, France; Université de Toulouse, UPS, Cancer Research Center of Toulouse, Equipe Labellisee Ligue Contre le Cancer and Laboratoire d'Excellence Toulouse Cancer, 31432 Toulouse, France
| | - Corinne Bousquet
- Inserm, U1037, 31432 Toulouse, France; Université de Toulouse, UPS, Cancer Research Center of Toulouse, Equipe Labellisee Ligue Contre le Cancer and Laboratoire d'Excellence Toulouse Cancer, 31432 Toulouse, France
| | - Mieke Dewerchin
- Vesalius Research Center, VIB, University of Leuven, 3000 Leuven, Belgium
| | - Stephane Pyronnet
- Inserm, U1037, 31432 Toulouse, France; Université de Toulouse, UPS, Cancer Research Center of Toulouse, Equipe Labellisee Ligue Contre le Cancer and Laboratoire d'Excellence Toulouse Cancer, 31432 Toulouse, France
| | | | - Peter Carmeliet
- Vesalius Research Center, VIB, University of Leuven, 3000 Leuven, Belgium
| | - Barbara Garmy-Susini
- Inserm, U1037, 31432 Toulouse, France; Université de Toulouse, UPS, Cancer Research Center of Toulouse, Equipe Labellisee Ligue Contre le Cancer and Laboratoire d'Excellence Toulouse Cancer, 31432 Toulouse, France.
| |
Collapse
|