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Khan WH, Ahmad R, Alam R, Khan N, Rather IA, Wani MY, Singh RB, Ahmad A. Role of ribosomal pathways and comorbidity in COVID-19: Insight from SARS-CoV-2 proteins and host proteins interaction network analysis. Heliyon 2024; 10:e29967. [PMID: 38694063 PMCID: PMC11059120 DOI: 10.1016/j.heliyon.2024.e29967] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Revised: 04/17/2024] [Accepted: 04/18/2024] [Indexed: 05/03/2024] Open
Abstract
The COVID-19 pandemic has become a significant global issue in terms of public health. While it is largely associated with respiratory complications, recent reports indicate that patients also experience neurological symptoms and other health issues. The objective of this study is to examine the network of protein-protein interactions (PPI) between SARS-CoV-2 proteins and human host proteins, pinpoint the central genes within this network implicated in disease pathology, and assess their viability as targets for drug development. The study adopts a network-based approach to construct a network of 29 SARS-CoV-2 proteins interacting with 2896 host proteins, with 176 host genes being identified as interacting genes with all the viral proteins. Gene ontology and pathway analysis of these host proteins revealed their role in biological processes such as translation, mRNA splicing, and ribosomal pathways. We further identified EEF2, RPS3, RPL9, RPS16, and RPL11 as the top 5 most connected hub genes in the disease-causing network, with significant interactions among each other. These hub genes were found to be involved in ribosomal pathways and cytoplasmic translation. Further a disease-gene interaction was also prepared to investigate the role of hub genes in other disorders and to understand the condition of comorbidity in COVID-19 patients. We also identified 13 drug molecules having interactions with all the hub genes, and estradiol emerged as the top potential drug target for the COVID-19 patients. Our study provides valuable insights using the protein-protein interaction network of SARS-CoV-2 proteins with host proteins and highlights the molecular basis of manifestation of COVID-19 and proposes drug for repurposing. As the pandemic continues to evolve, it is anticipated that investigating SARS-CoV-2 proteins will remain a critical area of focus for researchers globally, particularly in addressing potential challenges posed by specific SARS-CoV-2 variants in the future.
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Affiliation(s)
- Wajihul Hasan Khan
- Department of Microbiology, All India Institute of Medical Sciences, Delhi, 110029, India
| | - Razi Ahmad
- Department of Chemistry, Indian Institute of Technology, Hauz Khas, New Delhi, 110016, India
| | - Ragib Alam
- Department of Microbiology, All India Institute of Medical Sciences, Delhi, 110029, India
| | - Nida Khan
- Department of Chemical Engineering, Indian Institute of Technology, Hauz Khas, New Delhi, 110016, India
| | - Irfan A. Rather
- Department of Biological Sciences, Faculty of Science, King Abdulaziz University, Jeddah, 21589, Saudi Arabia
| | - Mohmmad Younus Wani
- Department of Chemistry, College of Science, University of Jeddah, Jeddah, 21589, Saudi Arabia
| | - R.K. Brojen Singh
- School of Computational and Integrative Sciences, Jawaharlal Nehru University, New Delhi, 110067, India
| | - Aijaz Ahmad
- Clinical Microbiology and Infectious Diseases, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, 2193, South Africa
- Division of Pulmonary, Allergy, Critical Care, and Sleep Medicine, Department of Medicine, University of Pittsburgh Medical Center, Pittsburgh, PA, 15213, USA
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Zhu Z, Fang C, Xu H, Yuan L, Du Y, Ni Y, Xu Y, Shao A, Zhang A, Lou M. Anoikis resistance in diffuse glioma: The potential therapeutic targets in the future. Front Oncol 2022; 12:976557. [PMID: 36046036 PMCID: PMC9423707 DOI: 10.3389/fonc.2022.976557] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Accepted: 07/25/2022] [Indexed: 11/28/2022] Open
Abstract
Glioma is the most common malignant intracranial tumor and exhibits diffuse metastasis and a high recurrence rate. The invasive property of glioma results from cell detachment. Anoikis is a special form of apoptosis that is activated upon cell detachment. Resistance to anoikis has proven to be a protumor factor. Therefore, it is suggested that anoikis resistance commonly occurs in glioma and promotes diffuse invasion. Several factors, such as integrin, E-cadherin, EGFR, IGFR, Trk, TGF-β, the Hippo pathway, NF-κB, eEF-2 kinase, MOB2, hypoxia, acidosis, ROS, Hsp and protective autophagy, have been shown to induce anoikis resistance in glioma. In our present review, we aim to summarize the underlying mechanism of resistance and the therapeutic potential of these molecules.
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Affiliation(s)
- Zhengyang Zhu
- Department of Neurosurgery, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Chaoyou Fang
- Department of Neurosurgery, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Houshi Xu
- Department of Neurosurgery, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Ling Yuan
- Department of Neurosurgery, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yichao Du
- Department of Neurosurgery, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yunjia Ni
- Department of Neurosurgery, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yuanzhi Xu
- Department of Neurosurgery, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Anwen Shao
- Department of Neurosurgery, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
- Department of Neurosurgery, Clinical Research Center for Neurological Diseases of Zhejiang Province, Hangzhou, China
| | - Anke Zhang
- Department of Neurosurgery, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
- Department of Neurosurgery, Clinical Research Center for Neurological Diseases of Zhejiang Province, Hangzhou, China
| | - Meiqing Lou
- Department of Neurosurgery, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
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Eukaryotic Extension Factor 2 Kinase may Affect the Occurrence and Development of Glioblastoma Through Immune Cell Infiltration. Neurochem Res 2022; 47:3670-3681. [PMID: 35849271 DOI: 10.1007/s11064-022-03679-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Revised: 06/30/2022] [Accepted: 07/06/2022] [Indexed: 10/17/2022]
Abstract
Glioblastoma (GBM) is one of the most common malignancies among primary brain tumors in adults, featuring a poor prognosis and a high recurrence rate. Eukaryotic elongation factor 2 kinase (eEF2K) is a calcium/calmodulin-dependent protein kinase that is involved in promoting tumor cell proliferation, migration, invasion, and survival. However, its expression level in GBM, its prognostic impact and correlation with immune infiltration are not yet known. In this study, we used The Cancer Genome Atlas (TCGA) database to explore the potential molecular mechanisms of eEF2K in GBM development and clinical prognosis in terms of gene expression, survival status, immune infiltration, and associated cellular pathways. We found that eEF2K expression levels were elevated in GBM, but eEF2K was not associated with the prognosis of GBM patients; eEF2K expression in GBM was associated with multiple immune cell infiltrations. These results show a statistical correlation between eEF2K expression and the development of GBM and immune cell infiltration, which helps us to understand the roles of eEF2K in GBM from different perspectives.
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Deng G, Zeng F, He Y, Meng Y, Sun H, Su J, Zhao S, Cheng Y, Chen X, Yin M. EEF2K silencing inhibits tumour progression through repressing SPP1 and synergises with BET inhibitors in melanoma. Clin Transl Med 2022; 12:e722. [PMID: 35184394 PMCID: PMC8858631 DOI: 10.1002/ctm2.722] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 01/11/2022] [Accepted: 01/17/2022] [Indexed: 01/05/2023] Open
Affiliation(s)
- Guangtong Deng
- Department of Dermatology Hunan Engineering Research Center of Skin Health and Disease Hunan Key Laboratory of Skin Cancer and Psoriasis Xiangya Hospital Central South University Changsha Hunan China
- National Clinical Research Center for Geriatric Disorders Xiangya Hospital Central South University Changsha Hunan China
| | - Furong Zeng
- Department of Dermatology Hunan Engineering Research Center of Skin Health and Disease Hunan Key Laboratory of Skin Cancer and Psoriasis Xiangya Hospital Central South University Changsha Hunan China
- National Clinical Research Center for Geriatric Disorders Xiangya Hospital Central South University Changsha Hunan China
- Department of Oncology Xiangya Hospital Central South University Changsha Hunan China
| | - Yi He
- Department of Dermatology Hunan Engineering Research Center of Skin Health and Disease Hunan Key Laboratory of Skin Cancer and Psoriasis Xiangya Hospital Central South University Changsha Hunan China
- National Clinical Research Center for Geriatric Disorders Xiangya Hospital Central South University Changsha Hunan China
| | - Yu Meng
- Department of Dermatology Hunan Engineering Research Center of Skin Health and Disease Hunan Key Laboratory of Skin Cancer and Psoriasis Xiangya Hospital Central South University Changsha Hunan China
- National Clinical Research Center for Geriatric Disorders Xiangya Hospital Central South University Changsha Hunan China
| | - Huiyan Sun
- Department of Dermatology Hunan Engineering Research Center of Skin Health and Disease Hunan Key Laboratory of Skin Cancer and Psoriasis Xiangya Hospital Central South University Changsha Hunan China
- National Clinical Research Center for Geriatric Disorders Xiangya Hospital Central South University Changsha Hunan China
| | - Juan Su
- Department of Dermatology Hunan Engineering Research Center of Skin Health and Disease Hunan Key Laboratory of Skin Cancer and Psoriasis Xiangya Hospital Central South University Changsha Hunan China
- National Clinical Research Center for Geriatric Disorders Xiangya Hospital Central South University Changsha Hunan China
| | - Shuang Zhao
- Department of Dermatology Hunan Engineering Research Center of Skin Health and Disease Hunan Key Laboratory of Skin Cancer and Psoriasis Xiangya Hospital Central South University Changsha Hunan China
- National Clinical Research Center for Geriatric Disorders Xiangya Hospital Central South University Changsha Hunan China
| | - Yan Cheng
- Department of Pharmacy The Second Xiangya Hospital Central South University Changsha Hunan China
| | - Xiang Chen
- Department of Dermatology Hunan Engineering Research Center of Skin Health and Disease Hunan Key Laboratory of Skin Cancer and Psoriasis Xiangya Hospital Central South University Changsha Hunan China
- National Clinical Research Center for Geriatric Disorders Xiangya Hospital Central South University Changsha Hunan China
| | - Mingzhu Yin
- Department of Dermatology Hunan Engineering Research Center of Skin Health and Disease Hunan Key Laboratory of Skin Cancer and Psoriasis Xiangya Hospital Central South University Changsha Hunan China
- National Clinical Research Center for Geriatric Disorders Xiangya Hospital Central South University Changsha Hunan China
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Das JK, Ren Y, Kumar A, Peng HY, Wang L, Xiong X, Alaniz RC, de Figueiredo P, Ren X, Liu X, Ryazonov AG, Yang JM, Song J. Elongation factor-2 kinase is a critical determinant of the fate and antitumor immunity of CD8 + T cells. SCIENCE ADVANCES 2022; 8:eabl9783. [PMID: 35108044 PMCID: PMC8809536 DOI: 10.1126/sciadv.abl9783] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Accepted: 12/10/2021] [Indexed: 06/14/2023]
Abstract
eEF-2K has important roles in stress responses and cellular metabolism. We report here a previously unappreciated but critical role of eEF-2K in regulating the fate and cytocidal activity of CD8+ T cells. CD8+ T cells from eEF-2K KO mice were more proliferative but had lower survival than their wild-type counterparts after their activation, followed by occurrence of premature senescence and exhaustion. eEF-2K KO CD8+ T cells were more metabolically active and showed hyperactivation of the Akt-mTOR-S6K pathway. Loss of eEF-2K substantially impaired the activity of CD8+ T cells. Furthermore, the antitumor efficacy and tumor infiltration of the CAR-CD8+ T cells lacking eEF-2K were notably reduced as compared to the control CAR-CD8+ T cells. Thus, eEF-2K is critically required for sustaining the viability and function of cytotoxic CD8+ T cells, and therapeutic augmentation of this kinase may be exploited as a novel approach to reinforcing CAR-T therapy against cancer.
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Affiliation(s)
- Jugal Kishore Das
- Department of Microbial Pathogenesis and Immunology, Texas A&M University Health Science Center, Bryan, TX 77843, USA
| | - Yijie Ren
- Department of Microbial Pathogenesis and Immunology, Texas A&M University Health Science Center, Bryan, TX 77843, USA
| | - Anil Kumar
- Department of Microbial Pathogenesis and Immunology, Texas A&M University Health Science Center, Bryan, TX 77843, USA
| | - Hao-Yun Peng
- Department of Microbial Pathogenesis and Immunology, Texas A&M University Health Science Center, Bryan, TX 77843, USA
| | - Liqing Wang
- Department of Microbial Pathogenesis and Immunology, Texas A&M University Health Science Center, Bryan, TX 77843, USA
| | - Xiaofang Xiong
- Department of Microbial Pathogenesis and Immunology, Texas A&M University Health Science Center, Bryan, TX 77843, USA
| | - Robert C. Alaniz
- Department of Microbial Pathogenesis and Immunology, Texas A&M University Health Science Center, Bryan, TX 77843, USA
| | - Paul de Figueiredo
- Department of Microbial Pathogenesis and Immunology, Texas A&M University Health Science Center, Bryan, TX 77843, USA
- Norman Borlaug Center, Texas A&M University, College Station, TX 77843, USA
- Department of Veterinary Pathobiology, College of Veterinary Medicine, Texas A&M University, College Station, Texas 77843, USA
| | - Xingcong Ren
- Department of Veterinary Pathobiology, College of Veterinary Medicine, Texas A&M University, College Station, Texas 77843, USA
| | - Xiaoqi Liu
- Department of Toxicology and Cancer Biology, Department of Pharmacology and Nutritional Science, and Markey Cancer Center, University of Kentucky College of Medicine, Lexington, KY 40536, USA
| | - Alexey G. Ryazonov
- Department of Pharmacology, Rutgers Robert Wood Johnson Medical School, Piscataway, NJ 08854, USA
| | - Jin-Ming Yang
- Department of Toxicology and Cancer Biology, Department of Pharmacology and Nutritional Science, and Markey Cancer Center, University of Kentucky College of Medicine, Lexington, KY 40536, USA
| | - Jianxun Song
- Department of Microbial Pathogenesis and Immunology, Texas A&M University Health Science Center, Bryan, TX 77843, USA
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Zeng T, Xu M, Zhang W, Gu X, Zhao F, Liu X, Zhang X. Autophagy inhibition and microRNA‑199a‑5p upregulation in paclitaxel‑resistant A549/T lung cancer cells. Oncol Rep 2021; 46:149. [PMID: 34080652 PMCID: PMC8185510 DOI: 10.3892/or.2021.8100] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Accepted: 04/27/2021] [Indexed: 12/15/2022] Open
Abstract
Multidrug resistance (MDR) is one of the major reasons for the clinical failure of cancer chemotherapy. Autophagy activation serves a crucial role in MDR. However, the specific molecular mechanism linking autophagy with MDR remains unknown. The results of the present study demonstrated that autophagy was inhibited and microRNA (miR)-199a-5p levels were upregulated in MDR model lung cancer cells (A549/T and H1299/T) compared with those in the parental cell lines. Paclitaxel (PTX) treatment increased the expression levels of miR-199a-5p in parental lung cancer cells compared with those in PTX-untreated cells, and these expression levels were negatively correlated with PTX sensitivity of the cells. miR-199a-5p knockdown in A549/T cells induced autophagy and resensitized cells to multiple chemotherapeutic drugs including PTX, taxotere, topotecan, SN38, oxaliplatin and vinorelbine. By contrast, miR-199a-5p overexpression in A549 cells suppressed autophagy and desensitized cells to these chemotherapeutic drugs. Mechanistically, the results of the present study demonstrated that miR-199a-5p blocked autophagy by activating the PI3K/Akt/mTOR signaling pathway and inhibiting the protein expression of autophagy-related 5. Furthermore, p62 protein was identified as a direct target of miR-199a-5p; miR-199a-5p bound to p62 mRNA to decrease its mRNA and protein expression levels. In conclusion, the results of the present study suggested that miR-199a-5p may contribute to MDR development in lung cancer cells by inhibiting autophagy and targeting p62. The regulatory effect of miR-199a-5p on autophagy may provide novel insights for future multidrug-resistant lung cancer chemotherapy.
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Affiliation(s)
- Tianjiao Zeng
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, P.R. China
| | - Mingshi Xu
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, P.R. China
| | - Wanli Zhang
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, P.R. China
| | - Xiaofan Gu
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, P.R. China
| | - Fangqing Zhao
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, P.R. China
| | - Xuan Liu
- Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, P.R. China
| | - Xiongwen Zhang
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, P.R. China
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7
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Elongation factor eEF2 kinase and autophagy jointly promote survival of cancer cells. Biochem J 2021; 478:1547-1569. [PMID: 33779695 DOI: 10.1042/bcj20210126] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 03/22/2021] [Accepted: 03/29/2021] [Indexed: 01/07/2023]
Abstract
Cells within solid tumours can become deprived of nutrients; in order to survive, they need to invoke mechanisms to conserve these resources. Using cancer cells in culture in the absence of key nutrients, we have explored the roles of two potential survival mechanisms, autophagy and elongation factor 2 kinase (eEF2K), which, when activated, inhibits the resource-intensive elongation stage of protein synthesis. Both processes are regulated through the nutrient-sensitive AMP-activated protein kinase and mechanistic target of rapamycin complex 1 signalling pathways. We find that disabling both autophagy and eEF2K strongly compromises the survival of nutrient-deprived lung and breast cancer cells, whereas, for example, knocking out eEF2K alone has little effect. Contrary to some earlier reports, we find no evidence that eEF2K regulates autophagy. Unexpectedly, eEF2K does not facilitate survival of prostate cancer PC3 cells. Thus, eEF2K and autophagy enable survival of certain cell-types in a mutually complementary manner. To explore this further, we generated, by selection, cells which were able to survive nutrient starvation even when autophagy and eEF2K were disabled. Proteome profiling using mass spectrometry revealed that these 'resistant' cells showed lower levels of diverse proteins which are required for energy-consuming processes such as protein and fatty acid synthesis, although different clones of 'resistant cells' appear to adapt in dissimilar ways. Our data provide further information of the ways that human cells cope with nutrient limitation and to understanding of the utility of eEF2K as a potential target in oncology.
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8
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Targeting eukaryotic elongation factor-2 kinase suppresses the growth and peritoneal metastasis of ovarian cancer. Cell Signal 2021; 81:109938. [PMID: 33539938 DOI: 10.1016/j.cellsig.2021.109938] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Revised: 01/26/2021] [Accepted: 01/27/2021] [Indexed: 12/25/2022]
Abstract
Ovarian cancer (OC) is the deadliest gynecological cancer and is currently incurable with standard treatment regimens. Early invasion, intraperitoneal metastasis, and an aggressive course are the hallmarks of OC. The major reason for poor prognosis is a lack of molecular targets and highly effective targeted therapies. Therefore, identification of novel molecular targets and therapeutic strategies is urgently needed to improve OC survival. Herein we report that eukaryotic elongation factor-2 kinase (EF2K) is highly upregulated in primary and drug-resistant OC cells and its expresssion associated with progression free survival TCGA database) and promotes cell proliferation, survival, and invasion. Downregulation of EF2K reduced expression of integrin β1 and cyclin D1 and the activity of the Src, phosphoinositide 3-kinase/AKT, and nuclear factor-κB signaling pathways. Also, in vivo, therapeutic targeting of EF2K by using single-lipid nanoparticles containing siRNA led to substantial inhibition of ovarian tumor growth and peritoneal metastasis in nude mouse models. Furthermore, EF2K inhibition led to robust apoptosis and markedly reduced intratumoral proliferation in vivo in ovarian tumor xenografts and intraperitoneal metastatic models. Collectively, our data suggest for the first time that EF2K plays an important role in OC growth, metastasis, and progression and may serve as a novel therapeutic target in OCs.
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Thomas M, Davis T, Nell T, Sishi B, Engelbrecht AM. Amino Acid Starvation Sensitizes Resistant Breast Cancer to Doxorubicin-Induced Cell Death. Front Cell Dev Biol 2020; 8:565915. [PMID: 33178685 PMCID: PMC7593593 DOI: 10.3389/fcell.2020.565915] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Accepted: 09/14/2020] [Indexed: 01/07/2023] Open
Abstract
Many clinical trials are beginning to assess the effectiveness of compounds known to regulate autophagy in patients receiving anti-cancer chemotherapy. However, autophagy inhibition, through exogenous inhibitors, or activation, through starvation, has revealed conflicting roles in cancer management and chemotherapeutic outcome. This study aimed to assess the effect of amino acid starvation on doxorubicin-treated breast cancer cells by assessing the roles of autophagy and apoptosis. An in vitro breast cancer model consisting of the normal breast epithelial MCF12A and the metastatic breast cancer MDAMB231 cells was used. Apoptotic and autophagic parameters were assessed following doxorubicin treatments, alone or in combination with bafilomycin, ATG5 siRNA or amino acid starvation. Inhibition of autophagy, through ATG5 siRNA or bafilomycin treatment, increased caspase activity and intracellular doxorubicin concentrations in MCF12A and MDAMB231 cells during doxorubicin treatment. While amino acid starvation increased autophagic activity and decreased caspase activity and intracellular doxorubicin concentrations in MCF12A cells, no changes in autophagic parameters or caspase activity were observed in MDAMB231 cells. Our in vivo data showed that 24 h protein starvation during high dose doxorubicin treatment resulted in increased survival of tumor-bearing GFP-LC3 mice. Results from this study suggest that short term starvation during doxorubicin chemotherapy may be a realistic avenue for adjuvant therapy, especially with regards to the protection of non-cancerous cells. More research is however, needed to fully understand the regulation of autophagic flux during starvation.
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Affiliation(s)
- Mark Thomas
- Department of Physiological Sciences, Faculty of Natural Sciences, Stellenbosch University, Stellenbosch, South Africa
| | - Tanja Davis
- Department of Physiological Sciences, Faculty of Natural Sciences, Stellenbosch University, Stellenbosch, South Africa
| | - Theo Nell
- Department of Physiological Sciences, Faculty of Natural Sciences, Stellenbosch University, Stellenbosch, South Africa
| | - Balindiwe Sishi
- Department of Physiological Sciences, Faculty of Natural Sciences, Stellenbosch University, Stellenbosch, South Africa
| | - Anna-Mart Engelbrecht
- Department of Physiological Sciences, Faculty of Natural Sciences, Stellenbosch University, Stellenbosch, South Africa.,African Cancer Institute (ACI), Department of Global Health, Faculty of Medicine and Health Sciences, Stellenbosch University, Tygerberg, South Africa
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Ray E, Vaghasiya K, Sharma A, Shukla R, Khan R, Kumar A, Verma RK. Autophagy-Inducing Inhalable Co-crystal Formulation of Niclosamide-Nicotinamide for Lung Cancer Therapy. AAPS PharmSciTech 2020; 21:260. [PMID: 32944787 DOI: 10.1208/s12249-020-01803-z] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2020] [Accepted: 08/25/2020] [Indexed: 12/16/2022] Open
Abstract
Niclosamide (NIC), an anthelminthic drug, is found to be promising in overcoming the problem of various types of drug-resistant cancer. In spite of strong anti-proliferative effect, NIC shows low aqueous solubility, leading to poor bioavailability. To overcome this limitation, and enhance its physicochemical properties and pharmacokinetic profile, we used co-crystallization technique as a promising strategy. In this work, we brought together the crystal and particle engineering at a time using spray drying to enhance physicochemical and aerodynamic properties of co-crystal particle for inhalation purpose. We investigated the formation and evaluation of pharmaceutical co-crystals of niclosamide-nicotinamide (NIC-NCT) prepared by rapid, continuous and scalable spray drying method and compared with conventional solvent evaporation technique. The newly formed co-crystal was evaluated by XRPD, FTIR, Raman spectroscopy and DSC, which showed an indication of formation of H bonds between drug (NIC) and co-former (NCT) as a major binding force in co-crystal development. The particle geometry of co-crystals including spherical shape, size 1-5 μm and aerodynamic properties (ED, 97.1 ± 8.9%; MMAD, 3.61 ± 0.87 μm; FPF, 71.74 ± 6.9% and GSD 1.46) attributes suitable for inhalation. For spray-dried co-crystal systems, an improvement in solubility characteristics (≥ 14.8-fold) was observed, relative to pure drug. To investigate the anti-proliferative activity, NIC-NCT co-crystals were investigated on A549 human lung adenomas cells, which showed a superior cytotoxic activity compared with pure drug. Mechanistically, NIC-NCT co-crystals enhanced autophagic flux in cancer cell which demonstrates autophagy-mediated cell death as shown by confocal microscopy. This technique could help in improving bioavailability of drug, hence reducing the need for high dosages and signifying a novel paradigm for future clinical applications.
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Karakas D, Ozpolat B. Eukaryotic elongation factor-2 kinase (eEF2K) signaling in tumor and microenvironment as a novel molecular target. J Mol Med (Berl) 2020; 98:775-787. [PMID: 32377852 DOI: 10.1007/s00109-020-01917-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Revised: 04/26/2020] [Accepted: 04/28/2020] [Indexed: 12/25/2022]
Abstract
Eukaryotic elongation factor-2 kinase (eEF2K), an atypical member of alpha-kinase family, is highly overexpressed in breast, pancreatic, brain, and lung cancers, and associated with poor survival in patients. eEF2K promotes cell proliferation, survival, and aggressive tumor characteristics, leading to tumor growth and progression. While initial studies indicated that eEF2K acts as a negative regulator of protein synthesis by suppressing peptide elongation phase, later studies demonstrated that it has multiple functions and promotes cell cycle, angiogenesis, migration, and invasion as well as induction of epithelial-mesenchymal transition through induction of integrin β1, SRC/FAK, PI3K/AKT, cyclin D1, VEGF, ZEB1, Snail, and MMP-2. Under stress conditions such as hypoxia and metabolic distress, eEF2K is activated by several signaling pathways and slows down protein synthesis and helping cells to save energy and survive. In vivo therapeutic targeting of eEF2K by genetic methods inhibits tumor growth in various tumor models, validating it as a potential molecular target. Recent studies suggest that eEF2K plays a role in tumor microenvironment cells by monocyte chemoattractant protein-1 (MCP-1) and accumulation of tumor-associated macrophages. Due to its clinical significance and the pivotal role in tumorigenesis and progression, eEF2K is considered as an important therapeutic target in solid tumors. However, currently, there is no specific and potent inhibitor for translation into clinical studies. Here, we aim to systematically review current knowledge regarding eEF2K in tumor biology, microenvironment, and development of eEF2K targeted inhibitors and therapeutics.
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Affiliation(s)
- Didem Karakas
- Department of Molecular Biology and Genetics, Faculty of Arts and Sciences, Istinye University, Istanbul, Turkey
| | - Bulent Ozpolat
- Department of Experimental Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA.
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12
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Zheng Z, Li G. Mechanisms and Therapeutic Regulation of Pyroptosis in Inflammatory Diseases and Cancer. Int J Mol Sci 2020; 21:ijms21041456. [PMID: 32093389 PMCID: PMC7073143 DOI: 10.3390/ijms21041456] [Citation(s) in RCA: 107] [Impact Index Per Article: 26.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Revised: 02/16/2020] [Accepted: 02/17/2020] [Indexed: 02/07/2023] Open
Abstract
Programmed Cell Death (PCD) is considered to be a pathological form of cell death when mediated by an intracellular program and it balances cell death with survival of normal cells. Pyroptosis, a type of PCD, is induced by the inflammatory caspase cleavage of gasdermin D (GSDMD) and apoptotic caspase cleavage of gasdermin E (GSDME). This review aims to summarize the latest molecular mechanisms about pyroptosis mediated by pore-forming GSDMD and GSDME proteins that permeabilize plasma and mitochondrial membrane activating pyroptosis and apoptosis. We also discuss the potentiality of pyroptosis as a therapeutic target in human diseases. Blockade of pyroptosis by compounds can treat inflammatory disease and pyroptosis activation contributes to cancer therapy.
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Affiliation(s)
| | - Guorong Li
- Correspondence: ; Tel.: +86-531-8618-2690
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13
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Wang YY, Liu XL, Zhao R. Induction of Pyroptosis and Its Implications in Cancer Management. Front Oncol 2019; 9:971. [PMID: 31616642 PMCID: PMC6775187 DOI: 10.3389/fonc.2019.00971] [Citation(s) in RCA: 144] [Impact Index Per Article: 28.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Accepted: 09/12/2019] [Indexed: 12/13/2022] Open
Abstract
Pyroptosis is a gasdermins mediated programmed cell death, which has been widely studied in inflammatory disease models. Recently, there are growing evidences that pyroptosis can be chemically induced in cancer cells without any bacterial or viral infection. Pyroptosis may affect all stages of carcinogenesis and has become a new topic in cancer research. In this review, we first briefly introduced pyroptosis. In the subsequent section, we discussed the induction of pyroptosis in cancer and its potential role as a promising target for cancer therapy. In addition, the biological characteristics of gasdermin D (GSDMD) and gasdermin E (GSDME), two important pyroptosis substrates, and their prognostic role in cancer management were reviewed. These results help us to understand the pathogenesis of cancer and develop new drugs, which based on pyroptosis modulation, for cancer patients.
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Affiliation(s)
- Yan-Yang Wang
- Department of Radiation Oncology, General Hospital of Ningxia Medical University, Yinchuan, China.,Cancer Institute, Ningxia Medical University, Yinchuan, China
| | - Xin-Lan Liu
- Department of Medical Oncology, General Hospital of Ningxia Medical University, Yinchuan, China
| | - Ren Zhao
- Department of Radiation Oncology, General Hospital of Ningxia Medical University, Yinchuan, China.,Cancer Institute, Ningxia Medical University, Yinchuan, China
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14
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Yu P, Wang HY, Tian M, Li AX, Chen XS, Wang XL, Zhang Y, Cheng Y. Eukaryotic elongation factor-2 kinase regulates the cross-talk between autophagy and pyroptosis in doxorubicin-treated human melanoma cells in vitro. Acta Pharmacol Sin 2019; 40:1237-1244. [PMID: 30914761 DOI: 10.1038/s41401-019-0222-z] [Citation(s) in RCA: 85] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Accepted: 02/21/2019] [Indexed: 01/07/2023] Open
Abstract
Eukaryotic elongation factor-2 kinase (eEF-2K), a negative regulator of protein synthesis, has been shown to play an important role in modulating autophagy and apoptosis in tumor cells under various stresses. In this study, we investigated the regulatory role of eEF-2K in pyroptosis (a new form of programmed necrosis) in doxorubicin-treated human melanoma cells. We found that doxorubicin (0.5-5 μmol/L) induced pyroptosis in melanoma cell lines SK-MEL-5, SK-MEL-28, and A-375 with high expression of DFNA5, but not in human breast cancer cell line MCF-7 with little expression of DFNA5. On the other hand, doxorubicin treatment activated autophagy in the melanoma cells; inhibition of autophagy by transfecting the cells with siRNA targeting Beclin1 or by pretreatment with chloroquine (20 μmol/L) significantly augmented pyroptosis, thus sensitizing the melanoma cells to doxorubicin. We further demonstrated that doxorubicin treatment activated eEF-2K in the melanoma cells, and silencing of eEF-2K blunted autophagic responses, but promoted doxorubicin-induced pyroptotic cell death. Taken together, the above results demonstrate that eEF-2K dictates the cross-talk between pyroptosis and autophagy in doxorubicin-treated human melanoma cells; suppression of eEF-2K results in inhibiting autophagy and augmenting pyroptosis, thus modulating the sensitivity of melanoma cells to doxorubicin, suggesting that targeting eEF-2K may reinforce the antitumor efficacy of doxorubicin, offering a new insight into tumor chemotherapy.
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15
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What is the impact of eukaryotic elongation factor 2 kinase on cancer: A systematic review. Eur J Pharmacol 2019; 857:172470. [DOI: 10.1016/j.ejphar.2019.172470] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Revised: 06/08/2019] [Accepted: 06/17/2019] [Indexed: 11/19/2022]
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16
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Bircan HA, Gurbuz N, Pataer A, Caner A, Kahraman N, Bayraktar E, Bayraktar R, Erdogan MA, Kabil N, Ozpolat B. Elongation factor-2 kinase (eEF-2K) expression is associated with poor patient survival and promotes proliferation, invasion and tumor growth of lung cancer. Lung Cancer 2018; 124:31-39. [DOI: 10.1016/j.lungcan.2018.07.027] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Revised: 07/19/2018] [Accepted: 07/19/2018] [Indexed: 12/20/2022]
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17
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Bahmad HF, Mouhieddine TH, Chalhoub RM, Assi S, Araji T, Chamaa F, Itani MM, Nokkari A, Kobeissy F, Daoud G, Abou-Kheir W. The Akt/mTOR pathway in cancer stem/progenitor cells is a potential therapeutic target for glioblastoma and neuroblastoma. Oncotarget 2018; 9:33549-33561. [PMID: 30323898 PMCID: PMC6173359 DOI: 10.18632/oncotarget.26088] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2018] [Accepted: 08/23/2018] [Indexed: 12/12/2022] Open
Abstract
Nervous system tumors represent some of the highly aggressive cancers in both children and adults, particularly neuroblastoma and glioblastoma. Many studies focused on the pathogenic role of the Akt pathway and the mechanistic target of Rapamycin (mTOR) complex in mediating the progression of various types of cancer, which designates the Akt/mTOR signaling pathway as a master regulator for cancer. Current studies are also elucidating the mechanisms of cancer stem cells (CSCs) in replenishing tumors and explicating the strong correlation between the Akt/mTOR pathway and CSC biology. This instigates the development of novel treatments that target CSCs via inhibiting this pathway to prevent recurrence in various cancer subtypes. In accordance, neuroblastoma and glioblastoma tumors are believed to originate from stem/progenitor cells or dedifferentiated mature neural/glial cells transformed into CSCs, which warrants targeting this subpopulation of CSCs in these tumors. In our study, Triciribine and Rapamycin were used to assess the role of inhibiting two different points of the Akt/mTOR pathway in vitro on U251 (glioblastoma) and SH-SY5Y (neuroblastoma) human cell lines and their CSCs. We showed that both drugs minimally decrease the survival of U251 and SH-SY5Y cells in a 2D model, while this effect was much more pronounced in a 3D culture model. Triciribine and Rapamycin decreased migratory abilities of both cell lines and decreased their sphere-forming units (SFU) by extinguishing their CSC populations. Together, we concluded that Rapamycin and Triciribine proved to be effective in the in vitro treatment of glioblastoma and neuroblastoma, by targeting their CSC population.
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Affiliation(s)
- Hisham F Bahmad
- Department of Anatomy, Cell Biology and Physiological Sciences, Faculty of Medicine, American University of Beirut, Beirut, Lebanon
| | - Tarek H Mouhieddine
- Department of Anatomy, Cell Biology and Physiological Sciences, Faculty of Medicine, American University of Beirut, Beirut, Lebanon.,Current Address: Department of Medical Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA
| | - Reda M Chalhoub
- Department of Anatomy, Cell Biology and Physiological Sciences, Faculty of Medicine, American University of Beirut, Beirut, Lebanon.,Current Address: Medical Scientist Training Program, College of Medicine, Medical University of South Carolina, Charleston, SC, USA
| | - Sahar Assi
- Department of Anatomy, Cell Biology and Physiological Sciences, Faculty of Medicine, American University of Beirut, Beirut, Lebanon
| | - Tarek Araji
- Department of Anatomy, Cell Biology and Physiological Sciences, Faculty of Medicine, American University of Beirut, Beirut, Lebanon
| | - Farah Chamaa
- Department of Anatomy, Cell Biology and Physiological Sciences, Faculty of Medicine, American University of Beirut, Beirut, Lebanon
| | - Muhieddine M Itani
- Department of Anatomy, Cell Biology and Physiological Sciences, Faculty of Medicine, American University of Beirut, Beirut, Lebanon
| | - Amaly Nokkari
- Department of Biochemistry and Molecular Genetics, Faculty of Medicine, American University of Beirut, Beirut, Lebanon
| | - Firas Kobeissy
- Department of Biochemistry and Molecular Genetics, Faculty of Medicine, American University of Beirut, Beirut, Lebanon
| | - Georges Daoud
- Department of Anatomy, Cell Biology and Physiological Sciences, Faculty of Medicine, American University of Beirut, Beirut, Lebanon
| | - Wassim Abou-Kheir
- Department of Anatomy, Cell Biology and Physiological Sciences, Faculty of Medicine, American University of Beirut, Beirut, Lebanon
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18
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Suppression of eEF-2K-mediated autophagy enhances the cytotoxicity of raddeanin A against human breast cancer cells in vitro. Acta Pharmacol Sin 2018; 39:642-648. [PMID: 29239350 DOI: 10.1038/aps.2017.139] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2017] [Accepted: 08/16/2017] [Indexed: 11/08/2022] Open
Abstract
Recent evidence shows that raddeanin A (RA), an oleanane-type triterpenoid saponin extracted from Anemone raddeana Regel, exerts remarkable cytotoxicity against cancer cells in vitro and in vivo. In addition, RA has also been found to activate autophagy in human gastric cancer cells. In this study, we investigated the molecular mechanisms underlying RA-induced autophagy as well as the relationship between RA-induced autophagy and its cytotoxicity in human breast cancer cells in vitro. Treatment with RA (2-8 μmol/L) dose-dependently enhanced autophagy, as evidenced by increased LC3 levels in breast cancer cell lines T47D, MCF-7 and MDA-MB-231. Furthermore, the Akt-mTOR-eEF-2K signaling pathway was demonstrated to be involved in RA-induced activation of autophagy in the 3 breast cancer cell lines. Treatment with RA (2-10 μmol/L) dose-dependently induced apoptosis in the 3 breast cancer cell lines. Pretreatment with the autophagy inhibitor chloroquine (CQ, 20 μmol/L) significantly enhanced RA-caused cytotoxicity via promoting apoptosis. In conclusion, our results suggest that modulating autophagy can reinforce the cytotoxicity of RA against human breast cancer cells.
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19
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Ji C, Xu Q, Guo L, Wang X, Ren Y, Zhang H, Zhu W, Ming Z, Yuan Y, Ren X, Song J, Cheng Y, Yang J, Zhang Y. eEF-2 Kinase-targeted miR-449b confers radiation sensitivity to cancer cells. Cancer Lett 2018; 418:64-74. [DOI: 10.1016/j.canlet.2018.01.014] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Revised: 12/27/2017] [Accepted: 01/08/2018] [Indexed: 10/18/2022]
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20
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Mesclon F, Lambert-Langlais S, Carraro V, Parry L, Hainault I, Jousse C, Maurin AC, Bruhat A, Fafournoux P, Averous J. Decreased ATF4 expression as a mechanism of acquired resistance to long-term amino acid limitation in cancer cells. Oncotarget 2018; 8:27440-27453. [PMID: 28460466 PMCID: PMC5432347 DOI: 10.18632/oncotarget.15828] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Accepted: 02/12/2017] [Indexed: 02/06/2023] Open
Abstract
The uncontrolled growth of tumor can lead to the formation of area deprived in nutrients. Due to their high genetic instability, tumor cells can adapt and develop resistance to this pro-apoptotic environment. Among the resistance mechanisms, those involved in the resistance to long-term amino acid restriction are not elucidated. A long-term amino acid restriction is particularly deleterious since nine of them cannot be synthetized by the cells. In order to determine how cancer cells face a long-term amino acid deprivation, we developed a cell model selected for its capacity to resist a long-term amino acid limitation. We exerted a selection pressure on mouse embryonic fibroblast to isolate clones able to survive with low amino acid concentration. The study of several clones revealed an alteration of the eiF2α/ATF4 pathway. Compared to the parental cells, the clones exhibited a decreased expression of the transcription factor ATF4 and its target genes. Likewise, the knock-down of ATF4 in parental cells renders them resistant to amino acid deprivation. Moreover, this association between a low level of ATF4 protein and the resistance to amino acid deprivation was also observed in the cancer cell line BxPC-3. This resistance was abolished when ATF4 was overexpressed. Therefore, decreasing ATF4 expression may be one important mechanism for cancer cells to survive under prolonged amino acid deprivation.
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Affiliation(s)
- Florent Mesclon
- Université Clermont Auvergne, INRA, UNH, Unité de Nutrition Humaine, CRNH Auvergne, F-63000 Clermont-Ferrand, France
| | - Sarah Lambert-Langlais
- Department of Medical Biochemistry and Molecular Biology, CHU de Clermont-Ferrand, 63003 Clermont-Ferrand Cedex 1, France
| | - Valérie Carraro
- Université Clermont Auvergne, INRA, UNH, Unité de Nutrition Humaine, CRNH Auvergne, F-63000 Clermont-Ferrand, France
| | - Laurent Parry
- Université Clermont Auvergne, INRA, UNH, Unité de Nutrition Humaine, CRNH Auvergne, F-63000 Clermont-Ferrand, France
| | - Isabelle Hainault
- Institute of Cardiometabolism and Nutrition, Université Pierre et Marie Curie, INSERM, UMR S1138, Centre de Recherche des Cordeliers, 75006 Paris, France
| | - Céline Jousse
- Université Clermont Auvergne, INRA, UNH, Unité de Nutrition Humaine, CRNH Auvergne, F-63000 Clermont-Ferrand, France
| | - Anne-Catherine Maurin
- Université Clermont Auvergne, INRA, UNH, Unité de Nutrition Humaine, CRNH Auvergne, F-63000 Clermont-Ferrand, France
| | - Alain Bruhat
- Université Clermont Auvergne, INRA, UNH, Unité de Nutrition Humaine, CRNH Auvergne, F-63000 Clermont-Ferrand, France
| | - Pierre Fafournoux
- Université Clermont Auvergne, INRA, UNH, Unité de Nutrition Humaine, CRNH Auvergne, F-63000 Clermont-Ferrand, France
| | - Julien Averous
- Université Clermont Auvergne, INRA, UNH, Unité de Nutrition Humaine, CRNH Auvergne, F-63000 Clermont-Ferrand, France
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21
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Wang Y, Huang G, Wang Z, Qin H, Mo B, Wang C. Elongation factor-2 kinase acts downstream of p38 MAPK to regulate proliferation, apoptosis and autophagy in human lung fibroblasts. Exp Cell Res 2018; 363:291-298. [PMID: 29355493 DOI: 10.1016/j.yexcr.2018.01.019] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Revised: 01/12/2018] [Accepted: 01/15/2018] [Indexed: 12/16/2022]
Abstract
Idiopathic pulmonary fibrosis (IPF) is a chronic, fatal and progressive fibro-proliferative lung disease, and fibroblast-to-myofibroblast differentiation is a crucial process in the development of IPF. Elongation factor-2 kinase (eEF2K) has been reported to play an important role in various disease types, but the role of eEF2K in IPF is unknown. In this study, we investigated the role of eEF2K in normal lung fibroblast (NHLF) proliferation, differentiation, apoptosis, and autophagy as well as the interaction between eEF2K and p38 MAPK signaling through in vitro experiments. We found that the inhibition of eEF2K markedly augmented cell proliferation and differentiation, suppressed apoptosis and autophagy, and reversed the anti-fibrotic effects of a p38 MAPK inhibitor. Together, our results indicate that eEF2K might inhibit TGF-β1-induced NHLF proliferation and differentiation and activate NHLF cell apoptosis and autophagy through p38 MAPK signaling, which might ameliorate lung fibroblast-to-myofibroblast differentiation.
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Affiliation(s)
- Yanni Wang
- Department of Respiratory Medcine (Department of Respiiratory and Critical Care Medcine), Key Cite of National Clinical Research Center for Respiratory Disease. Xiangya Hospital, Central South University, 87 Xiangya Road, Changsha, Hunan, China
| | - Guojin Huang
- Laboratory of Respiratory Disease, Affiliated Hospital of Guilin Medical University, 15 Lequn Road, Guilin, Guangxi, China
| | - Zhixia Wang
- Department of Respiratory Medcine (Department of Respiiratory and Critical Care Medcine), Key Cite of National Clinical Research Center for Respiratory Disease. Xiangya Hospital, Central South University, 87 Xiangya Road, Changsha, Hunan, China
| | - Huiping Qin
- Department of Respiratory Medcine (Department of Respiiratory and Critical Care Medcine), Key Cite of National Clinical Research Center for Respiratory Disease. Xiangya Hospital, Central South University, 87 Xiangya Road, Changsha, Hunan, China
| | - Biwen Mo
- Department of Respiratory, Guilin People's Hospital affiliated of Guilin Medical University, 15 Lequn Road, Guilin, Guangxi, China
| | - Changming Wang
- Department of Respiratory, Guilin People's Hospital affiliated of Guilin Medical University, 12 Wenming Road, Guilin, Guangxi, China.
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22
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Eukaryotic Elongation Factor 2 Kinase (eEF2K) in Cancer. Cancers (Basel) 2017; 9:cancers9120162. [PMID: 29186827 PMCID: PMC5742810 DOI: 10.3390/cancers9120162] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Revised: 11/24/2017] [Accepted: 11/25/2017] [Indexed: 12/31/2022] Open
Abstract
Eukaryotic elongation factor 2 kinase (eEF2K) is a highly unusual protein kinase that negatively regulates the elongation step of protein synthesis. This step uses the vast majority of the large amount of energy and amino acids required for protein synthesis. eEF2K activity is controlled by an array of regulatory inputs, including inhibition by signalling through mammalian target of rapamycin complex 1 (mTORC1). eEF2K is activated under conditions of stress, such as energy depletion or nutrient deprivation, which can arise in poorly-vascularised tumours. In many such stress conditions, eEF2K exerts cytoprotective effects. A growing body of data indicates eEF2K aids the growth of solid tumours in vivo. Since eEF2K is not essential (in mice) under ‘normal’ conditions, eEF2K may be a useful target in the treatment of solid tumours. However, some reports suggest that eEF2K may actually impair tumorigenesis in some situations. Such a dual role of eEF2K in cancer would be analogous to the situation for other pathways involved in cell metabolism, such as autophagy and mTORC1. Further studies are needed to define the role of eEF2K in different tumour types and at differing stages in tumorigenesis, and to assess its utility as a therapeutic target in oncology.
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23
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Fu Z, Luo W, Wang J, Peng T, Sun G, Shi J, Li Z, Zhang B. Malat1 activates autophagy and promotes cell proliferation by sponging miR-101 and upregulating STMN1, RAB5A and ATG4D expression in glioma. Biochem Biophys Res Commun 2017; 492:480-486. [PMID: 28834690 DOI: 10.1016/j.bbrc.2017.08.070] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Accepted: 08/18/2017] [Indexed: 10/19/2022]
Abstract
The long noncoding RNA Malat1 has been reported to be an oncogene that promotes tumor progress and correlates with prognosis in glioma. Growing evidence shows that autophagy plays a very important role in tumorigenesis and tumor cell survival, but whether Malat1 regulates autophagy in glioma is still unclear. In this study, we found that Malat1 expression and autophagy activity were significantly increased in glioma tissues compared with adjacent normal tissues. Additionally, Malat1 level was positively correlated with the expression of LC3-II (autophagy marker) mRNA in vivo. In vitro assays revealed that Malat1 significantly promoted autophagy activation and cell proliferation in glioma cells. More importantly, inhibition of autophagy by 3-MA relieved Malat1-induced cell proliferation. These data demonstrated that Malat1 activates autophagy and increases cell proliferation in glioma. We further investigated the molecular mechanisms whereby Malat1 functioned on glioma cell autophagy and proliferation. We found that Malat1 served as an endogenous sponge to reduce miR-101 expression by directly binding to miR-101. Moreover, Malat1 abolished the suppression effects of miR-101 on glioma cell autophagy and proliferation, which involved in upregulating the expression of miR-101 targets STMN1, RAB5A and ATG4D. Overall, our study elucidated a novel Malat1-miR-101-STMN1/RAB5A/ATG4D regulatory network that Malat1 activates autophagy and promotes cell proliferation by sponging miR-101 and upregulating STMN1, RAB5A and ATG4D expression in glioma cells.
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Affiliation(s)
- Zhenqiang Fu
- Department of Neurology, First Affiliated Hospital of Zhengzhou University, China
| | - Wenzheng Luo
- Department of Neurosurgery, First Affiliated Hospital of Zhengzhou University, China
| | - Jingtao Wang
- Department of Neurology, First Affiliated Hospital of Zhengzhou University, China
| | - Tao Peng
- Department of Neurology, First Affiliated Hospital of Zhengzhou University, China
| | - Guifang Sun
- Department of Neurology, First Affiliated Hospital of Zhengzhou University, China
| | - Jingyu Shi
- Department of Neurology, Luoyang Central Hospital, China
| | - Zhihong Li
- Department of Neurology, Zhengzhou Central Hospital, China
| | - Boai Zhang
- Department of Neurology, First Affiliated Hospital of Zhengzhou University, China.
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24
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Guha P, Kaptan E, Gade P, Kalvakolanu DV, Ahmed H. Tunicamycin induced endoplasmic reticulum stress promotes apoptosis of prostate cancer cells by activating mTORC1. Oncotarget 2017; 8:68191-68207. [PMID: 28978108 PMCID: PMC5620248 DOI: 10.18632/oncotarget.19277] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Accepted: 06/10/2017] [Indexed: 01/11/2023] Open
Abstract
Studies suggest that tunicamycin may work as a therapeutic drug to cancer cells by inducing stress in the endoplasmic reticulum (ER) through unfolded protein response (UPR) and thereby promoting apoptosis. However, mechanisms of the prolonged activation of the UPR under sustained ER stress in the regulation of cell apoptosis are largely unknown. To delineate the role of candidate genes in the apoptotic process under ER stress and to search for new therapeutic strategies to treat metastatic castration resistant prostate cancer, we performed whole genome expression microarray analysis in tunicamycin treated metastatic androgen-insensitive prostate cancer cells, PC-3. Among several induced genes, the expression of eNOS (NOS3) gene was remarkably high. The increased expression of eNOS activates mTORC1 through RagC. This results into an accumulation of p62 (SQSTM1) which facilitates aggregation of ubiquitinated protein thus compromising clearance of misfolded toxic protein aggregates. Lastly, association of p62 proteins and misfolded proteins promote reactive oxygen species (ROS) mediated mitochondrial apoptosis. Overall, our data demonstrate that tunicamycin induced ER stress promotes prostate cancer cell death by activating mTORC1 through eNOS-RagC pathway.
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Affiliation(s)
- Prasun Guha
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine and Institute of Marine and Environmental Technology, Baltimore, Maryland, USA.,Current address: The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Engin Kaptan
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine and Institute of Marine and Environmental Technology, Baltimore, Maryland, USA.,Current address: Department of Biology, Istanbul University, Vezneciler, Istanbul, Turkey
| | - Padmaja Gade
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Dhananjaya V Kalvakolanu
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, Maryland, USA.,University of Maryland Greenebaum Cancer Center, Baltimore, Maryland, USA
| | - Hafiz Ahmed
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine and Institute of Marine and Environmental Technology, Baltimore, Maryland, USA.,University of Maryland Greenebaum Cancer Center, Baltimore, Maryland, USA.,Current address: GlycoMantra Inc., Baltimore, Maryland, USA
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25
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Li Z, Chang CM, Wang L, Zhang P, Shu HKG. Cyclooxygenase-2 Induction by Amino Acid Deprivation Requires p38 Mitogen-Activated Protein Kinase in Human Glioma Cells. Cancer Invest 2017; 35:237-247. [PMID: 28333553 PMCID: PMC6300144 DOI: 10.1080/07357907.2017.1292517] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Revised: 11/02/2016] [Accepted: 02/05/2017] [Indexed: 02/07/2023]
Abstract
Glioblastomas (GBMs) are malignant brain tumors that can outstrip nutrient supplies due to rapid growth. Cyclooxygenase-2 (COX-2) has been linked to GBMs and may contribute to their aggressive phenotypes. Amino acid starvation results in COX-2 mRNA and protein induction in multiple human glioma cell lines in a process requiring p38 mitogen-activated protein kinase (p38-MAPK) and the Sp1 transcription factor. Increased vascular endothelial growth factor expression results from starvation-dependent COX-2 induction. These data suggest that COX-2 induction with amino acid deprivation may be a part of the adaptation of glioma cells to these conditions, and potentially alter cellular response to anti-neoplastic therapy.
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Affiliation(s)
- Zhiwen Li
- Department of Radiation Oncology and the Winship Cancer Institute, Emory University, Atlanta, GA 30322, USA
- Departments of Anesthesiology First Hospital of Jilin University, Changchun, Jilin 130021, China
| | - Chi-Ming Chang
- Department of Radiation Oncology and the Winship Cancer Institute, Emory University, Atlanta, GA 30322, USA
| | - Lanfang Wang
- Department of Radiation Oncology and the Winship Cancer Institute, Emory University, Atlanta, GA 30322, USA
| | - Ping Zhang
- Hepatobiliary and Pancreatic Surgery, First Hospital of Jilin University, Changchun, Jilin 130021, China
| | - Hui-Kuo G. Shu
- Department of Radiation Oncology and the Winship Cancer Institute, Emory University, Atlanta, GA 30322, USA
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26
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Liu L, Huang P, Wang Z, Chen N, Tang C, Lin Z, Peng P. Inhibition of eEF-2 kinase sensitizes human nasopharyngeal carcinoma cells to lapatinib-induced apoptosis through the Src and Erk pathways. BMC Cancer 2016; 16:813. [PMID: 27756261 PMCID: PMC5069787 DOI: 10.1186/s12885-016-2853-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2016] [Accepted: 10/10/2016] [Indexed: 11/12/2022] Open
Abstract
Background Previous studies have reported that eEF-2 kinase is associated with tumour cell sensitivity to certain therapies. In the present study, we investigated the relationship between eEF-2 kinase and lapatinib, a dual inhibitor of EGFR and HER-2, in nasopharyngeal carcinoma (NPC) cells. Methods The effect of treatment on the growth and proliferation of NPC cells was measured by three methods: cell counting, crystal violet staining and colony counting. Apoptosis was evaluated by flow cytometry to determine Annexin V-APC/7-AAD and cleaved PARP levels, and the results were further confirmed by Western blot analysis. The expression of eEF-2 kinase and the impacts of different treatments on different signalling pathways were analysed by Western blot analysis. Results The expression of eEF-2 kinase was significantly associated with NPC cell sensitivity to lapatinib. Therefore, suppression of this kinase could increase the cytocidal effect of lapatinib, as well as reduce cell viability and colony formation. Furthermore, inhibition of eEF-2 kinase, by either RNA interference (eEF-2 kinase siRNA or shRNA) or pharmacological inhibition (NH125), enhanced lapatinib-induced apoptosis of NPC cells. The results also showed that lapatinib combined with NH125 had a synergistic effect in NPC cells. In addition, mechanistic analyses revealed that downregulation of the ERK1/2 and Src pathways, but not the AKT pathway, was involved in this sensitizing effect. Conclusions The results of this study suggest that targeting eEF-2 kinase may improve the efficacy of therapeutic interventions such as lapatinib in NPC cells.
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Affiliation(s)
- Lin Liu
- Department of Medical Oncology, The Fifth Affiliated Hospital of Sun-Yat-Sen University, 52 Mei Hua Road East, Zhu Hai, 519000, Guangdong Province, People's Republic of China
| | - PeiYu Huang
- State Key Laboratory of Oncology in South China; Collaborative Innovation Center for Cancer Medicine; Department of nasopharyngeal carcinoma, Sun Yat-sen University Cancer Center, Guangzhou, China
| | - ZhiHui Wang
- Department of Medical Oncology, The Fifth Affiliated Hospital of Sun-Yat-Sen University, 52 Mei Hua Road East, Zhu Hai, 519000, Guangdong Province, People's Republic of China
| | - Nan Chen
- Department of Medical Oncology, The Fifth Affiliated Hospital of Sun-Yat-Sen University, 52 Mei Hua Road East, Zhu Hai, 519000, Guangdong Province, People's Republic of China
| | - Con Tang
- Department of Surgical Oncology, The Fifth Affiliated Hospital of Sun-Yat-Sen University, Zhu Hai, China
| | - Zhong Lin
- Department of Medical Oncology, The Fifth Affiliated Hospital of Sun-Yat-Sen University, 52 Mei Hua Road East, Zhu Hai, 519000, Guangdong Province, People's Republic of China
| | - PeiJian Peng
- Department of Medical Oncology, The Fifth Affiliated Hospital of Sun-Yat-Sen University, 52 Mei Hua Road East, Zhu Hai, 519000, Guangdong Province, People's Republic of China.
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Li X, Liu YJ, Xia JM, Zeng XY, Liao XX, Wei HY, Hu CL, Jing XL, Dai G. Activation of autophagy improved the neurologic outcome after cardiopulmonary resuscitation in rats. Am J Emerg Med 2016; 34:1511-8. [DOI: 10.1016/j.ajem.2016.05.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Revised: 05/02/2016] [Accepted: 05/07/2016] [Indexed: 10/21/2022] Open
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Takatani T, Shirakawa J, Roe MW, Leech CA, Maier BF, Mirmira RG, Kulkarni RN. IRS1 deficiency protects β-cells against ER stress-induced apoptosis by modulating sXBP-1 stability and protein translation. Sci Rep 2016; 6:28177. [PMID: 27378176 PMCID: PMC4932502 DOI: 10.1038/srep28177] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Accepted: 05/31/2016] [Indexed: 01/05/2023] Open
Abstract
Endoplasmic reticulum (ER) stress is among several pathological features that underlie β-cell failure in the development of type 1 and type 2 diabetes. Adaptor proteins in the insulin/insulin-like-growth factor-1 signaling pathways, such as insulin receptor substrate-1 (IRS1) and IRS2, differentially impact β-cell survival but the underlying mechanisms remain unclear. Here we report that β-cells deficient in IRS1 (IRS1KO) are resistant, while IRS2 deficiency (IRS2KO) makes them susceptible to ER stress-mediated apoptosis. IRS1KOs exhibited low nuclear accumulation of spliced XBP-1 due to its poor stability, in contrast to elevated accumulation in IRS2KO. The reduced nuclear accumulation in IRS1KO was due to protein instability of Xbp1 secondary to proteasomal degradation. IRS1KO also demonstrated an attenuation in their general translation status in response to ER stress revealed by polyribosomal profiling. Phosphorylation of eEF2 was dramatically increased in IRS1KO enabling the β-cells to adapt to ER stress by blocking translation. Furthermore, significantly high ER calcium (Ca2+) was detected in IRS1KO β-cells even upon induction of ER stress. These observations suggest that IRS1 could be a therapeutic target for β-cell protection against ER stress-mediated cell death by modulating XBP-1 stability, protein synthesis, and Ca2+ storage in the ER.
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Affiliation(s)
- Tomozumi Takatani
- Islet Cell and Regenerative Biology, Joslin Diabetes Center, Department of Medicine, Brigham and Women's Hospital, Harvard Stem Cell Institute, Harvard Medical School, Boston, MA, USA
| | - Jun Shirakawa
- Islet Cell and Regenerative Biology, Joslin Diabetes Center, Department of Medicine, Brigham and Women's Hospital, Harvard Stem Cell Institute, Harvard Medical School, Boston, MA, USA
| | - Michael W Roe
- Department of Medicine, State University of New York (SUNY), Upstate Medical University, Syracuse, NY, USA
| | - Colin A Leech
- Department of Medicine, State University of New York (SUNY), Upstate Medical University, Syracuse, NY, USA
| | - Bernhard F Maier
- Department of Pediatrics and Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Raghavendra G Mirmira
- Department of Pediatrics and Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN, USA.,Department of Cellular and Integrative Physiology, Department of Biochemistry and Molecular Biology, Department of Medicine, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Rohit N Kulkarni
- Islet Cell and Regenerative Biology, Joslin Diabetes Center, Department of Medicine, Brigham and Women's Hospital, Harvard Stem Cell Institute, Harvard Medical School, Boston, MA, USA
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Fritzen AM, Frøsig C, Jeppesen J, Jensen TE, Lundsgaard AM, Serup AK, Schjerling P, Proud CG, Richter EA, Kiens B. Role of AMPK in regulation of LC3 lipidation as a marker of autophagy in skeletal muscle. Cell Signal 2016; 28:663-74. [DOI: 10.1016/j.cellsig.2016.03.005] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Revised: 03/03/2016] [Accepted: 03/09/2016] [Indexed: 12/26/2022]
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30
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Cheng Y, Ren X, Yuan Y, Shan Y, Li L, Chen X, Zhang L, Takahashi Y, Yang JW, Han B, Liao J, Li Y, Harvey H, Ryazanov A, Robertson GP, Wan G, Liu D, Chen AF, Tao Y, Yang JM. eEF-2 kinase is a critical regulator of Warburg effect through controlling PP2A-A synthesis. Oncogene 2016; 35:6293-6308. [PMID: 27181208 DOI: 10.1038/onc.2016.166] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Revised: 03/29/2016] [Accepted: 04/03/2016] [Indexed: 12/15/2022]
Abstract
Cancer cells predominantly metabolize glucose by glycolysis to produce energy in order to meet their metabolic requirement, a phenomenon known as Warburg effect. Although Warburg effect is considered a peculiarity critical for survival and proliferation of cancer cells, the regulatory mechanisms behind this phenomenon remain incompletely understood. We report here that eukaryotic elongation factor-2 kinase (eEF-2K), a negative regulator of protein synthesis, has a critical role in promoting glycolysis in cancer cells. We showed that deficiency in eEF-2K significantly reduced the uptake of glucose and decreased the productions of lactate and adenosine triphosphate in tumor cells and in the Ras-transformed mouse embryonic fibroblasts. We further demonstrated that the promotive effect of eEF-2K on glycolysis resulted from the kinase-mediated restriction of synthesis of the protein phosphatase 2A-A (PP2A-A), a key factor that facilitates the ubiquitin-proteasomal degradation of c-Myc protein, as knockdown of eEF-2K expression led to a significant increase in PP2A-A protein synthesis and remarkable downregulation of c-Myc and pyruvate kinase M2 isoform, the key glycolytic enzyme transcriptionally activated by c-Myc. In addition, depletion of eEF-2K reduced the ability of the transformed cells to proliferate and enhanced the sensitivity of tumor cells to chemotherapy both in vitro and in vivo. These results, which uncover a role of the eEF-2K-mediated control of PP2A-A in tumor cell glycolysis, provide new insights into the regulation of the Warburg effect.
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Affiliation(s)
- Y Cheng
- Department of Pharmacology, School of Pharmaceutical Sciences, Central South University, Changsha, China.,Department of Pharmacology, The Penn State Hershey Cancer Institute, The Pennsylvania State University College of Medicine and Milton S Hershey Medical Center, Hershey, PA, USA
| | - X Ren
- Department of Pharmacology, The Penn State Hershey Cancer Institute, The Pennsylvania State University College of Medicine and Milton S Hershey Medical Center, Hershey, PA, USA
| | - Y Yuan
- Department of Pharmaceutical Sciences, Washington State University College of Pharmacy, Spokane, WA, USA
| | - Y Shan
- Department of Pharmacology, The Penn State Hershey Cancer Institute, The Pennsylvania State University College of Medicine and Milton S Hershey Medical Center, Hershey, PA, USA
| | - L Li
- Department of Pharmacology, School of Pharmaceutical Sciences, Central South University, Changsha, China
| | - X Chen
- Department of Pharmacology, School of Pharmaceutical Sciences, Central South University, Changsha, China
| | - L Zhang
- Department of Pharmacology, The Penn State Hershey Cancer Institute, The Pennsylvania State University College of Medicine and Milton S Hershey Medical Center, Hershey, PA, USA
| | - Y Takahashi
- Department of Pharmacology, The Penn State Hershey Cancer Institute, The Pennsylvania State University College of Medicine and Milton S Hershey Medical Center, Hershey, PA, USA
| | - J W Yang
- Department of Pharmacology, The Penn State Hershey Cancer Institute, The Pennsylvania State University College of Medicine and Milton S Hershey Medical Center, Hershey, PA, USA
| | - B Han
- Department of Pathology, The Penn State Hershey Cancer Institute, The Pennsylvania State University College of Medicine and Milton S Hershey Medical Center, Hershey, PA, USA
| | - J Liao
- Division of Biostatistics and Bioinformatics, The Penn State Hershey Cancer Institute, The Pennsylvania State University College of Medicine and Milton S Hershey Medical Center, Hershey, PA, USA
| | - Y Li
- Department of Pharmacology, The Penn State Hershey Cancer Institute, The Pennsylvania State University College of Medicine and Milton S Hershey Medical Center, Hershey, PA, USA
| | - H Harvey
- Department of Medicine, The Penn State Hershey Cancer Institute, The Pennsylvania State University College of Medicine and Milton S Hershey Medical Center, Hershey, PA, USA
| | - A Ryazanov
- Department of Pharmacology, Robert wood Jonson Medical School, Rutgers University, Piscataway, NJ, USA
| | - G P Robertson
- Department of Pharmacology, The Penn State Hershey Cancer Institute, The Pennsylvania State University College of Medicine and Milton S Hershey Medical Center, Hershey, PA, USA
| | - G Wan
- Department of Pharmacology, The Penn State Hershey Cancer Institute, The Pennsylvania State University College of Medicine and Milton S Hershey Medical Center, Hershey, PA, USA
| | - D Liu
- Department of Pharmaceutical Sciences, Washington State University College of Pharmacy, Spokane, WA, USA
| | - A F Chen
- Center for Vascular and Translational Medicine, College of Pharmacy, and The Third Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Y Tao
- Cancer Research Institute, School of Basic Medicine, and Key Laboratory of Carcinogenesis and Cancer Invasion, Ministry of Education, Central South University, Changsha, China
| | - J-M Yang
- Department of Pharmacology, The Penn State Hershey Cancer Institute, The Pennsylvania State University College of Medicine and Milton S Hershey Medical Center, Hershey, PA, USA
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Abstract
Eukaryotic elongation factor 2 kinase (eEF2K) belongs to the small family of atypical protein kinases termed α-kinases, and is the only calcium/calmodulin (Ca/CaM)-dependent member of that group. It phosphorylates and inactivates eEF2, to slow down the rate of elongation, the stage in mRNA translation that consumes almost all the energy and amino acids consumed by protein synthesis. In addition to activation by Ca/CaM, eEF2K is also regulated by an array of other regulatory inputs, which include inhibition by the nutrient- and growth-factor activated signalling pathways. Recent evidence shows that eEF2K plays an important role in learning and memory, processes that require the synthesis of new proteins and involve Ca-mediated signalling. eEF2K is activated under conditions of nutrient and energy depletion. In cancer cells, or certain tumours, eEF2K exerts cytoprotective effects, which probably reflect its ability to inhibit protein synthesis, and nutrient consumption, under starvation conditions. eEF2K is being evaluated as a potential therapeutic target in cancer.
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32
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Moore CEJ, Wang X, Xie J, Pickford J, Barron J, Regufe da Mota S, Versele M, Proud CG. Elongation factor 2 kinase promotes cell survival by inhibiting protein synthesis without inducing autophagy. Cell Signal 2016; 28:284-93. [PMID: 26795954 PMCID: PMC4760274 DOI: 10.1016/j.cellsig.2016.01.005] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Revised: 01/14/2016] [Accepted: 01/15/2016] [Indexed: 01/10/2023]
Abstract
Eukaryotic elongation factor 2 kinase (eEF2K) inhibits the elongation stage of protein synthesis by phosphorylating its only known substrate, eEF2. eEF2K is tightly regulated by nutrient-sensitive signalling pathways. For example, it is inhibited by signalling through mammalian target of rapamycin complex 1 (mTORC1). It is therefore activated under conditions of nutrient deficiency. Here we show that inhibiting eEF2K or knocking down its expression renders cancer cells sensitive to death under nutrient-starved conditions, and that this is rescued by compounds that block protein synthesis. This implies that eEF2K protects nutrient-deprived cells by inhibiting protein synthesis. Cells in which signalling through mTORC1 is highly active are very sensitive to nutrient withdrawal. Inhibiting mTORC1 protects them. Our data reveal that eEF2K makes a substantial contribution to the cytoprotective effect of mTORC1 inhibition. eEF2K is also reported to promote another potentially cytoprotective process, autophagy. We have used several approaches to test whether inhibition or loss of eEF2K affects autophagy under a variety of conditions. We find no evidence that eEF2K is involved in the activation of autophagy in the cell types we have studied. We conclude that eEF2K protects cancer cells against nutrient starvation by inhibiting protein synthesis rather than by activating autophagy. Eukaryotic elongation factor-2 kinase helps cancer cells survive nutrient starvation and is an attractive anti-cancer target. eEF2K has been reported to promote autophagy; however, our evidence shows eEF2K does not modulate autophagy. eEF2K protects cells by inhibiting protein synthesis.
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Affiliation(s)
- Claire E J Moore
- Centre for Biological Sciences, University of Southampton, Southampton, SO17 1BJ, United Kingdom; South Australian Health & Medical Research Institute, North Terrace, Adelaide, SA5000, Australia
| | - Xuemin Wang
- Centre for Biological Sciences, University of Southampton, Southampton, SO17 1BJ, United Kingdom; South Australian Health & Medical Research Institute, North Terrace, Adelaide, SA5000, Australia; School of Biological Sciences, University of Adelaide, Adelaide SA5005, Australia
| | - Jianling Xie
- Centre for Biological Sciences, University of Southampton, Southampton, SO17 1BJ, United Kingdom; South Australian Health & Medical Research Institute, North Terrace, Adelaide, SA5000, Australia
| | - Jo Pickford
- Centre for Biological Sciences, University of Southampton, Southampton, SO17 1BJ, United Kingdom
| | - John Barron
- Centre for Biological Sciences, University of Southampton, Southampton, SO17 1BJ, United Kingdom
| | - Sergio Regufe da Mota
- Centre for Biological Sciences, University of Southampton, Southampton, SO17 1BJ, United Kingdom
| | - Matthias Versele
- Janssen Research & Development, Turnhoutseweg 30, 2340 Beerse, Belgium
| | - Christopher G Proud
- Centre for Biological Sciences, University of Southampton, Southampton, SO17 1BJ, United Kingdom; South Australian Health & Medical Research Institute, North Terrace, Adelaide, SA5000, Australia; School of Biological Sciences, University of Adelaide, Adelaide SA5005, Australia.
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33
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Tavares CDJ, Devkota AK, Dalby KN, Cho EJ. Application of Eukaryotic Elongation Factor-2 Kinase (eEF-2K) for Cancer Therapy: Expression, Purification, and High-Throughput Inhibitor Screening. Methods Mol Biol 2016; 1360:19-33. [PMID: 26501899 DOI: 10.1007/978-1-4939-3073-9_2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Protein kinases have emerged as an important class of therapeutic targets, as they are known to be involved in pathological pathways linked to numerous human disorders. Major efforts to discover kinase inhibitors in both academia and pharmaceutical companies have centered on the development of robust assays and cost-effective approaches to isolate them. Drug discovery procedures often start with hit identification for lead development, by screening a library of chemicals using an appropriate assay in a high-throughput manner. Considering limitations unique to each assay technique and screening capability, intelligent integration of various assay schemes and level of throughput, in addition to the choice of chemical libraries, is the key to success of this initial step. Here, we describe the purification of the protein kinase, eEF-2K, and the utilization of three biochemical assays in the course of identifying small molecules that block its enzymatic reaction.
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Affiliation(s)
- Clint D J Tavares
- Division of Medicinal Chemistry, College of Pharmacy, The University of Texas at Austin, Austin, TX, 78712, USA
| | - Ashwini K Devkota
- Texas Screening Alliance for Cancer Therapeutics, The University of Texas at Austin, Austin, TX, 78712, USA
| | - Kevin N Dalby
- Division of Medicinal Chemistry, College of Pharmacy, The University of Texas at Austin, Austin, TX, 78712, USA.
- Texas Screening Alliance for Cancer Therapeutics, The University of Texas at Austin, Austin, TX, 78712, USA.
| | - Eun Jeong Cho
- Texas Screening Alliance for Cancer Therapeutics, The University of Texas at Austin, Austin, TX, 78712, USA.
- College of Pharmacy, The University of Texas at Austin, Austin, TX, 78712, USA.
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34
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Regulated stability of eukaryotic elongation factor 2 kinase requires intrinsic but not ongoing activity. Biochem J 2015; 467:321-31. [DOI: 10.1042/bj20150089] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Eukaryotic elongation factor 2 kinase (eEF2K) is an atypical protein kinase which negatively regulates protein synthesis, is activated under stress conditions and plays a role in cytoprotection, e.g. in cancer cells. It is regarded as a possible target for therapeutic intervention in solid tumours. Earlier studies showed that eEF2K is degraded by a proteasome-dependent pathway in response to genotoxic stress and that this requires a phosphodegron that includes an autophosphorylation site. Thus, application of eEF2K inhibitors would stabilize eEF2K, partially negating the effects of inhibiting its activity. In the present study, we show that under a range of other stress conditions, including acidosis or treatment of cells with 2-deoxyglucose, eEF2K is also degraded. However, in these settings, the previously identified phosphodegron is not required for its degradation. Nevertheless, kinase-dead and other activity-deficient mutants of eEF2K are stabilized, as is a mutant lacking a critical autophosphorylation site (Thr348 in eEF2K), which is thought to be required for eEF2K and other α-kinases to achieve their active conformations. In contrast, application of small-molecule eEF2K inhibitors does not stabilize the protein. Our data suggest that achieving an active conformation, rather than eEF2K activity per se, is required for its susceptibility to degradation. Additional degrons and E3 ligases beyond those already identified are probably involved in regulating eEF2K levels. Our findings have significant implications for therapeutic targeting of eEF2K, e.g. in oncology.
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35
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Zhu H, Yang X, Liu J, Zhou L, Zhang C, Xu L, Qin Q, Zhan L, Lu J, Cheng H, Sun X. Eukaryotic elongation factor 2 kinase confers tolerance to stress conditions in cancer cells. Cell Stress Chaperones 2015; 20:217-20. [PMID: 25248493 PMCID: PMC4326389 DOI: 10.1007/s12192-014-0545-0] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2014] [Revised: 08/23/2014] [Accepted: 09/11/2014] [Indexed: 12/25/2022] Open
Abstract
Eukaryotic elongation factor 2 (eEF2) is a member of the GTP-binding translation elongation factor family that is essential for protein synthesis. eEF2 kinase (eEF2K) is a structurally and functionally unique protein kinase in the calmodulin-mediated signaling pathway. eEF2K phosphorylates eEF2, thereby inhibiting eEF2 function under stressful conditions. eEF2K regulates numerous processes, such as protein synthesis, cell cycle progression, and induction of autophagy and apoptosis in cancer cells. This review will demonstrate the mechanisms underlying eEF2K activity in cancer cells under different stresses, such as nutrient deprivation, hypoxia, and DNA damage via eEF2 regulation. In vivo, in vitro, and clinical studies indicated that eEF2K may be a novel biomarker and therapeutic target for cancer.
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Affiliation(s)
- Hongcheng Zhu
- />Department of Radiation Oncology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Xi Yang
- />Department of Radiation Oncology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Jia Liu
- />Department of Radiation Oncology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Lu Zhou
- />Department of Neurosurgery, Nanjing Drum Tower Hospital and Clinical College of Nanjing Medical University, Nanjing, China
| | - Chi Zhang
- />Department of Radiation Oncology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Liping Xu
- />Department of Radiation Oncology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Qin Qin
- />Department of Radiation Oncology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Liangliang Zhan
- />Department of Radiation Oncology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Jing Lu
- />Department of Radiation Oncology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Hongyan Cheng
- />Department of General Internal Medicine, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Xinchen Sun
- />Department of Radiation Oncology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
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Usui T, Nijima R, Sakatsume T, Otani K, Kameshima S, Okada M, Yamawaki H. Eukaryotic elongation factor 2 kinase controls proliferation and migration of vascular smooth muscle cells. Acta Physiol (Oxf) 2015; 213:472-80. [PMID: 25069823 DOI: 10.1111/apha.12354] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2014] [Revised: 07/14/2014] [Accepted: 07/17/2014] [Indexed: 11/27/2022]
Abstract
AIM Eukaryotic elongation factor 2 kinase (eEF2K), also known as calmodulin (CaM)-dependent protein kinase (CaMK) III, is a unique member of CaMK family protein. We have recently found that expression of eEF2K protein increased in mesenteric artery from spontaneously hypertensive rats. As pathogenesis of hypertension is in part regulated by vascular structural remodelling via proliferation and migration of vascular smooth muscle cells (SMCs), we tested the hypothesis that eEF2K controls SMCs proliferation and migration. METHODSAND RESULTS In rat mesenteric arterial SMCs, an eEF2K inhibitor, A-484954 (10 μm), significantly inhibited platelet-derived growth factor (PDGF)-BB (10 ng mL(-1) )-induced SMCs proliferation as determined by a cell counting and bromodeoxyuridine incorporation assay. PDGF-BB (10 ng mL(-1) )-induced SMCs migration was significantly inhibited by A-484954 (10 μm) as determined by a Boyden chamber assay. A-484954 (10 μm) significantly inhibited PDGF-BB (10 ng mL(-1) )-induced phosphorylation of eEF2K, extracellular signal-regulated kinase (ERK), Akt, p38 and heat-shock protein (HSP) 27 as determined by Western blotting. It was confirmed that a CaM inhibitor, W-7 (50 μm), inhibited PDGF-BB (10 ng mL(-1) )-induced phosphorylation of eEF2K. In an ex vivo mesenteric arterial ring assay, 10% foetal bovine serum-induced SMCs outgrowth was significantly inhibited by A-484954 (10 μm). CONCLUSION We for the first time revealed that eEF2K mediates PDGF-BB-induced SMCs proliferation and migration through activating ERK, Akt, p38 and HSP27 signals in a CaM-dependent manner. Our results suggest eEF2K as a novel pharmaceutical target for the prevention of hypertensive cardiovascular diseases.
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Affiliation(s)
- T. Usui
- Laboratory of Veterinary Pharmacology; School of Veterinary Medicine; Kitasato University; Towada Aomori Japan
| | - R. Nijima
- Laboratory of Veterinary Pharmacology; School of Veterinary Medicine; Kitasato University; Towada Aomori Japan
| | - T. Sakatsume
- Laboratory of Veterinary Pharmacology; School of Veterinary Medicine; Kitasato University; Towada Aomori Japan
| | - K. Otani
- Laboratory of Veterinary Pharmacology; School of Veterinary Medicine; Kitasato University; Towada Aomori Japan
| | - S. Kameshima
- Laboratory of Veterinary Pharmacology; School of Veterinary Medicine; Kitasato University; Towada Aomori Japan
| | - M. Okada
- Laboratory of Veterinary Pharmacology; School of Veterinary Medicine; Kitasato University; Towada Aomori Japan
| | - H. Yamawaki
- Laboratory of Veterinary Pharmacology; School of Veterinary Medicine; Kitasato University; Towada Aomori Japan
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Zhao YY, Tian Y, Zhang J, Xu F, Yang YP, Huang Y, Zhao HY, Zhang JW, Xue C, Lam MH, Yan L, Hu ZH, Dinglin XX, Zhang L. Effects of an oral allosteric AKT inhibitor (MK-2206) on human nasopharyngeal cancer in vitro and in vivo. DRUG DESIGN DEVELOPMENT AND THERAPY 2014; 8:1827-37. [PMID: 25336925 PMCID: PMC4199975 DOI: 10.2147/dddt.s67961] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Aim Protein kinase B (AKT) signaling frequently is deregulated in human cancers and plays an important role in nasopharyngeal carcinoma (NPC). This preclinical study investigated the effect of MK-2206, a potent allosteric AKT inhibitor, on human NPC cells in vitro and in vivo. Methods The effect of MK-2206 on the growth and proliferation of CNE-1, CNE-2, HONE-1, and SUNE-1 cells was assessed by Cell Counting Kit 8 and colony formation assay. Flow cytometry was performed to analyze cell cycle and apoptosis. The effects of MK-2206 on the AKT pathway were analyzed by Western blotting. Autophagy induction was evaluated via electron microscopy and Western blot. To test the effects of MK-2206 in vivo, CNE-2 cells were subcutaneously implanted into nude mice. Tumor-bearing mice were treated orally with MK-2206 or placebo. Tumors were harvested for immunohistochemical analysis. Results In vitro, MK-2206 inhibited the four NPC cell line growths and reduced the sizes of the colonies in a dose-dependent manner. At 72 and 96 hours, the half maximal inhibitory concentration (IC50) values of MK-2206 in CNE-1, CNE-2, and HONE-1 cell lines were 3–5 μM, whereas in SUNE-1, IC50 was less than 1 μM, and MK-2206 induced cell cycle arrest at the G1 phase. However, our study found no evidence of apoptosis. MK-2206 induced autophagy in NPC cells, as evidenced by electron microscopy and Western blot, and inhibited the growth of tumors that were subcutaneously implanted in mice. Inhibition of downstream phosphorylation through the PRAS40 and S6 pathways seems to be the main mechanism for the MK-2206-induced growth inhibition. Conclusion Our preclinical study suggests that MK-2206’s antiproliferative effect may be useful for NPC treatment; however, strategies for reinforcing this effect are needed to maximize clinical benefit.
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Affiliation(s)
- Yuan-Yuan Zhao
- Department of Medical Oncology, Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, and Collaborative Innovation Center for Cancer Medicine, Guangzhou, People's Republic of China
| | - Ying Tian
- Department of Medical Oncology, Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, and Collaborative Innovation Center for Cancer Medicine, Guangzhou, People's Republic of China
| | - Jing Zhang
- Department of Medical Oncology, the First Affiliated Hospital of Guang Zhou Traditional Chinese Medicine University, Guangzhou, People's Republic of China
| | - Fei Xu
- Department of Medical Oncology, Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, and Collaborative Innovation Center for Cancer Medicine, Guangzhou, People's Republic of China
| | - Yun-Peng Yang
- Department of Medical Oncology, Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, and Collaborative Innovation Center for Cancer Medicine, Guangzhou, People's Republic of China
| | - Yan Huang
- Department of Medical Oncology, Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, and Collaborative Innovation Center for Cancer Medicine, Guangzhou, People's Republic of China
| | - Hong-Yun Zhao
- National Anti-Cancer Drug Research Centre, Sun Yat-Sen University Cancer Center; State Key Laboratory of Oncology in South China, and Collaborative Innovation Center for Cancer Medicine, Guangzhou, People's Republic of China
| | - Jian-Wei Zhang
- The Six Affiliated Hospital of Sun Yat-Sen University, Guangzhou, People's Republic of China
| | - Cong Xue
- Department of Medical Oncology, Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, and Collaborative Innovation Center for Cancer Medicine, Guangzhou, People's Republic of China
| | | | - Li Yan
- Merck and Co Inc, North Wales, PA USA
| | - Zhi-Huang Hu
- Department of Medical Oncology, Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, and Collaborative Innovation Center for Cancer Medicine, Guangzhou, People's Republic of China
| | - Xiao-Xiao Dinglin
- Sun Yat-Sen Memorial Hospital, Guangzhou, People's Republic of China
| | - Li Zhang
- Department of Medical Oncology, Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, and Collaborative Innovation Center for Cancer Medicine, Guangzhou, People's Republic of China ; National Anti-Cancer Drug Research Centre, Sun Yat-Sen University Cancer Center; State Key Laboratory of Oncology in South China, and Collaborative Innovation Center for Cancer Medicine, Guangzhou, People's Republic of China
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Saito K, Iizuka Y, Ohta S, Takahashi S, Nakamura K, Saya H, Yoshida K, Kawakami Y, Toda M. Functional analysis of a novel glioma antigen, EFTUD1. Neuro Oncol 2014; 16:1618-29. [PMID: 25015090 DOI: 10.1093/neuonc/nou132] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND A cDNA library made from 2 glioma cell lines, U87MG and T98G, was screened by serological identification of antigens by recombinant cDNA expression (SEREX) using serum from a glioblastoma patient. Elongation factor Tu GTP binding domain containing protein 1 (EFTUD1), which is required for ribosome biogenesis, was identified. A cancer microarray database showed overexpression of EFTUD1 in gliomas, suggesting that EFTUD1 is a candidate molecular target for gliomas. METHODS EFTUD1 expression in glioma cell lines and glioma tissue was assessed by Western blot, quantitative PCR, and immunohistochemistry. The effect on ribosome biogenesis, cell growth, cell cycle, and induction of apoptosis and autophagy in glioma cells during the downregulation of EFTUD1 was investigated. To reveal the role of autophagy, the autophagy-blocker, chloroquine (CQ), was used in glioma cells downregulating EFTUD1. The effect of combining CQ with EFTUD1 inhibition in glioma cells was analyzed. RESULTS EFTUD1 expression in glioma cell lines and tissue was higher than in normal brain tissue. Downregulating EFTUD1 induced G1 cell-cycle arrest and apoptosis, leading to reduced glioma cell proliferation. The mechanism underlying this antitumor effect was impaired ribosome biogenesis via EFTUD1 inhibition. Additionally, protective autophagy was induced by glioma cells as an adaptive response to EFTUD1 inhibition. The antitumor effect induced by the combined treatment was significantly higher than that of either EFTUD1 inhibition or CQ alone. CONCLUSION These results suggest that EFTUD1 represents a novel therapeutic target and that the combination of EFTUD1 inhibition with autophagy blockade may be effective in the treatment of gliomas.
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Affiliation(s)
- Katsuya Saito
- Department of Neurosurgery, Keio University School of Medicine, Tokyo, Japan (K.S., S.T., K.Y., M.T.); Neuro-immunology Research Group, Keio University School of Medicine, Tokyo, Japan (Y.I., S.O., M.T.); Department of Physiology, Keio University School of Medicine, Tokyo, Japan (S.O.); Division of Cellular Signaling, Institute for Advanced Medical Research, Keio University School of Medicine, Tokyo, Japan (K.N., Y.K.); Division of Gene Regulation, Institute for Advanced Medical Research, Keio University School of Medicine, Tokyo, Japan (H.S.)
| | - Yukihiko Iizuka
- Department of Neurosurgery, Keio University School of Medicine, Tokyo, Japan (K.S., S.T., K.Y., M.T.); Neuro-immunology Research Group, Keio University School of Medicine, Tokyo, Japan (Y.I., S.O., M.T.); Department of Physiology, Keio University School of Medicine, Tokyo, Japan (S.O.); Division of Cellular Signaling, Institute for Advanced Medical Research, Keio University School of Medicine, Tokyo, Japan (K.N., Y.K.); Division of Gene Regulation, Institute for Advanced Medical Research, Keio University School of Medicine, Tokyo, Japan (H.S.)
| | - Shigeki Ohta
- Department of Neurosurgery, Keio University School of Medicine, Tokyo, Japan (K.S., S.T., K.Y., M.T.); Neuro-immunology Research Group, Keio University School of Medicine, Tokyo, Japan (Y.I., S.O., M.T.); Department of Physiology, Keio University School of Medicine, Tokyo, Japan (S.O.); Division of Cellular Signaling, Institute for Advanced Medical Research, Keio University School of Medicine, Tokyo, Japan (K.N., Y.K.); Division of Gene Regulation, Institute for Advanced Medical Research, Keio University School of Medicine, Tokyo, Japan (H.S.)
| | - Satoshi Takahashi
- Department of Neurosurgery, Keio University School of Medicine, Tokyo, Japan (K.S., S.T., K.Y., M.T.); Neuro-immunology Research Group, Keio University School of Medicine, Tokyo, Japan (Y.I., S.O., M.T.); Department of Physiology, Keio University School of Medicine, Tokyo, Japan (S.O.); Division of Cellular Signaling, Institute for Advanced Medical Research, Keio University School of Medicine, Tokyo, Japan (K.N., Y.K.); Division of Gene Regulation, Institute for Advanced Medical Research, Keio University School of Medicine, Tokyo, Japan (H.S.)
| | - Kenta Nakamura
- Department of Neurosurgery, Keio University School of Medicine, Tokyo, Japan (K.S., S.T., K.Y., M.T.); Neuro-immunology Research Group, Keio University School of Medicine, Tokyo, Japan (Y.I., S.O., M.T.); Department of Physiology, Keio University School of Medicine, Tokyo, Japan (S.O.); Division of Cellular Signaling, Institute for Advanced Medical Research, Keio University School of Medicine, Tokyo, Japan (K.N., Y.K.); Division of Gene Regulation, Institute for Advanced Medical Research, Keio University School of Medicine, Tokyo, Japan (H.S.)
| | - Hideyuki Saya
- Department of Neurosurgery, Keio University School of Medicine, Tokyo, Japan (K.S., S.T., K.Y., M.T.); Neuro-immunology Research Group, Keio University School of Medicine, Tokyo, Japan (Y.I., S.O., M.T.); Department of Physiology, Keio University School of Medicine, Tokyo, Japan (S.O.); Division of Cellular Signaling, Institute for Advanced Medical Research, Keio University School of Medicine, Tokyo, Japan (K.N., Y.K.); Division of Gene Regulation, Institute for Advanced Medical Research, Keio University School of Medicine, Tokyo, Japan (H.S.)
| | - Kazunari Yoshida
- Department of Neurosurgery, Keio University School of Medicine, Tokyo, Japan (K.S., S.T., K.Y., M.T.); Neuro-immunology Research Group, Keio University School of Medicine, Tokyo, Japan (Y.I., S.O., M.T.); Department of Physiology, Keio University School of Medicine, Tokyo, Japan (S.O.); Division of Cellular Signaling, Institute for Advanced Medical Research, Keio University School of Medicine, Tokyo, Japan (K.N., Y.K.); Division of Gene Regulation, Institute for Advanced Medical Research, Keio University School of Medicine, Tokyo, Japan (H.S.)
| | - Yutaka Kawakami
- Department of Neurosurgery, Keio University School of Medicine, Tokyo, Japan (K.S., S.T., K.Y., M.T.); Neuro-immunology Research Group, Keio University School of Medicine, Tokyo, Japan (Y.I., S.O., M.T.); Department of Physiology, Keio University School of Medicine, Tokyo, Japan (S.O.); Division of Cellular Signaling, Institute for Advanced Medical Research, Keio University School of Medicine, Tokyo, Japan (K.N., Y.K.); Division of Gene Regulation, Institute for Advanced Medical Research, Keio University School of Medicine, Tokyo, Japan (H.S.)
| | - Masahiro Toda
- Department of Neurosurgery, Keio University School of Medicine, Tokyo, Japan (K.S., S.T., K.Y., M.T.); Neuro-immunology Research Group, Keio University School of Medicine, Tokyo, Japan (Y.I., S.O., M.T.); Department of Physiology, Keio University School of Medicine, Tokyo, Japan (S.O.); Division of Cellular Signaling, Institute for Advanced Medical Research, Keio University School of Medicine, Tokyo, Japan (K.N., Y.K.); Division of Gene Regulation, Institute for Advanced Medical Research, Keio University School of Medicine, Tokyo, Japan (H.S.)
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Tavares CDJ, Ferguson SB, Giles DH, Wang Q, Wellmann RM, O'Brien JP, Warthaka M, Brodbelt JS, Ren P, Dalby KN. The molecular mechanism of eukaryotic elongation factor 2 kinase activation. J Biol Chem 2014; 289:23901-16. [PMID: 25012662 DOI: 10.1074/jbc.m114.577148] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Calmodulin (CaM)-dependent eukaryotic elongation factor 2 kinase (eEF-2K) impedes protein synthesis through phosphorylation of eukaryotic elongation factor 2 (eEF-2). It is subject to complex regulation by multiple upstream signaling pathways, through poorly described mechanisms. Precise integration of these signals is critical for eEF-2K to appropriately regulate protein translation rates. Here, an allosteric mechanism comprising two sequential conformations is described for eEF-2K activation. First, Ca(2+)/CaM binds eEF-2K with high affinity (Kd(CaM)(app) = 24 ± 5 nm) to enhance its ability to autophosphorylate Thr-348 in the regulatory loop (R-loop) by > 10(4)-fold (k(auto) = 2.6 ± 0.3 s(-1)). Subsequent binding of phospho-Thr-348 to a conserved basic pocket in the kinase domain potentially drives a conformational transition of the R-loop, which is essential for efficient substrate phosphorylation. Ca(2+)/CaM binding activates autophosphorylated eEF-2K by allosterically enhancing k(cat)(app) for peptide substrate phosphorylation by 10(3)-fold. Thr-348 autophosphorylation results in a 25-fold increase in the specificity constant (k(cat)(app)/K(m)(Pep-S) (app)), with equal contributions from k(cat)(app) and K(m)(Pep-S)(app), suggesting that peptide substrate binding is partly impeded in the unphosphorylated enzyme. In cells, Thr-348 autophosphorylation appears to control the catalytic output of active eEF-2K, contributing more than 5-fold to its ability to promote eEF-2 phosphorylation. Fundamentally, eEF-2K activation appears to be analogous to an amplifier, where output volume may be controlled by either toggling the power switch (switching on the kinase) or altering the volume control (modulating stability of the active R-loop conformation). Because upstream signaling events have the potential to modulate either allosteric step, this mechanism allows for exquisite control of eEF-2K output.
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Affiliation(s)
- Clint D J Tavares
- From the Graduate Program in Cell and Molecular Biology, the Division of Medicinal Chemistry, College of Pharmacy,
| | | | - David H Giles
- the Division of Medicinal Chemistry, College of Pharmacy
| | - Qiantao Wang
- the Division of Medicinal Chemistry, College of Pharmacy, the Department of Biomedical Engineering, Cockrell School of Engineering, and
| | | | - John P O'Brien
- the Department of Chemistry and Biochemistry, College of Natural Sciences, University of Texas, Austin, Texas 78712
| | | | - Jennifer S Brodbelt
- the Department of Chemistry and Biochemistry, College of Natural Sciences, University of Texas, Austin, Texas 78712
| | - Pengyu Ren
- the Department of Biomedical Engineering, Cockrell School of Engineering, and
| | - Kevin N Dalby
- From the Graduate Program in Cell and Molecular Biology, the Division of Medicinal Chemistry, College of Pharmacy,
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Xie CM, Liu XY, Sham KWY, Lai JMY, Cheng CHK. Silencing of EEF2K (eukaryotic elongation factor-2 kinase) reveals AMPK-ULK1-dependent autophagy in colon cancer cells. Autophagy 2014; 10:1495-508. [PMID: 24955726 PMCID: PMC4206530 DOI: 10.4161/auto.29164] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
EEF2K (eukaryotic elongation factor-2 kinase), also known as Ca2+/calmodulin-dependent protein kinase III, functions in downregulating peptide chain elongation through inactivation of EEF2 (eukaryotic translation elongation factor 2). Currently, there is a limited amount of information on the promotion of autophagic survival by EEF2K in breast and glioblastoma cell lines. However, the precise role of EEF2K in carcinogenesis as well as the underlying mechanism involved is still poorly understood. In this study, contrary to the reported autophagy-promoting activity of EEF2K in certain cancer cells, EEF2K is shown to negatively regulate autophagy in human colon cancer cells as indicated by the increase of LC3-II levels, the accumulation of LC3 dots per cell, and the promotion of autophagic flux in EEF2K knockdown cells. EEF2K negatively regulates cell viability, clonogenicity, cell proliferation, and cell size in colon cancer cells. Autophagy induced by EEF2K silencing promotes cell survival and does not potentiate the anticancer efficacy of the AKT inhibitor MK-2206. In addition, autophagy induced by silencing of EEF2K is attributed to induction of protein synthesis and activation of the AMPK-ULK1 pathway, independent of the suppression of MTOR activity and ROS generation. Knockdown of AMPK or ULK1 significantly abrogates EEF2K silencing-induced increase of LC3-II levels, accumulation of LC3 dots per cell as well as cell proliferation in colon cancer cells. In conclusion, silencing of EEF2K promotes autophagic survival via activation of the AMPK-ULK1 pathway in colon cancer cells. This finding suggests that upregulation of EEF2K activity may constitute a novel approach for the treatment of human colon cancer.
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Affiliation(s)
- Chuan-Ming Xie
- School of Biomedical Sciences; The Chinese University of Hong Kong; Hong Kong, China
| | - Xiao-Yu Liu
- School of Biomedical Sciences; The Chinese University of Hong Kong; Hong Kong, China
| | - Kathy W Y Sham
- School of Biomedical Sciences; The Chinese University of Hong Kong; Hong Kong, China
| | - Josie M Y Lai
- School of Biomedical Sciences; The Chinese University of Hong Kong; Hong Kong, China
| | - Christopher H K Cheng
- School of Biomedical Sciences; The Chinese University of Hong Kong; Hong Kong, China; Center of Novel Functional Molecules; The Chinese University of Hong Kong; Hong Kong, China
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Hait WN, Versele M, Yang JM. Surviving Metabolic Stress: Of Mice (Squirrels) and Men. Cancer Discov 2014; 4:646-9. [DOI: 10.1158/2159-8290.cd-14-0114] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Kenney JW, Moore CE, Wang X, Proud CG. Eukaryotic elongation factor 2 kinase, an unusual enzyme with multiple roles. Adv Biol Regul 2014; 55:15-27. [PMID: 24853390 DOI: 10.1016/j.jbior.2014.04.003] [Citation(s) in RCA: 132] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Accepted: 04/15/2014] [Indexed: 12/27/2022]
Abstract
Eukaryotic elongation factor 2 kinase (eEF2K) is a member of the small group of atypical 'α-kinases'. It phosphorylates and inhibits eukaryotic elongation factor 2, to slow down the elongation stage of protein synthesis, which normally consumes a great deal of energy and amino acids. The activity of eEF2K is normally dependent on calcium ions and calmodulin. eEF2K is also regulated by a plethora of other inputs, including inhibition by signalling downstream of anabolic signalling pathways such as the mammalian target of rapamycin complex 1. Recent data show that eEF2K helps to protect cancer cells against nutrient starvation and is also cytoprotective in other settings, including hypoxia. Growing evidence points to roles for eEF2K in neurological processes such as learning and memory and perhaps in depression.
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Affiliation(s)
- Justin W Kenney
- Centre for Biological Sciences, Life Sciences Building, University of Southampton, Southampton, SO16 7LB, UK
| | - Claire E Moore
- Centre for Biological Sciences, Life Sciences Building, University of Southampton, Southampton, SO16 7LB, UK
| | - Xuemin Wang
- Centre for Biological Sciences, Life Sciences Building, University of Southampton, Southampton, SO16 7LB, UK
| | - Christopher G Proud
- Centre for Biological Sciences, Life Sciences Building, University of Southampton, Southampton, SO16 7LB, UK.
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Akcakanat A, Hong DS, Meric-Bernstam F. Targeting translation initiation in breast cancer. ACTA ACUST UNITED AC 2014; 2:e28968. [PMID: 26779407 PMCID: PMC4705830 DOI: 10.4161/trla.28968] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2014] [Revised: 04/09/2014] [Accepted: 04/22/2014] [Indexed: 12/23/2022]
Abstract
Over the past 20 years, a better understanding of cancer biology, screening for early detection, improved adjuvant treatment, and targeted therapies have decreased the rate of breast cancer deaths. However, resistance to treatment is common, and new approaches are needed. Deregulation of translation initiation is associated with the commencement and progression of cancer. Often, translation initiation factors are overexpressed and the related signaling pathways activated in human tumors. Recently, a significant number of inhibitors that target translation factors and pathways have become available. These inhibitors are being tested alone or in combination with chemotherapeutic agents in clinical trials. The results are varied, and it is not yet clear which drug treatments most effectively inhibit tumor growth. This review highlights the pathways and downstream effects of the activation of translation and discusses targeting the control of translation initiation as a therapeutic approach in cancer, focusing on breast cancer clinical trials.
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Affiliation(s)
- Argun Akcakanat
- Department of Investigational Cancer Therapeutics; Houston, TX USA
| | - David S Hong
- Department of Investigational Cancer Therapeutics; Houston, TX USA
| | - Funda Meric-Bernstam
- Department of Investigational Cancer Therapeutics; Houston, TX USA; Department of Surgical Oncology; The University of Texas MD Anderson Cancer Center; Houston, TX USA
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Awan MUF, Deng Y. Role of autophagy and its significance in cellular homeostasis. Appl Microbiol Biotechnol 2014; 98:5319-28. [PMID: 24743981 DOI: 10.1007/s00253-014-5721-8] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2014] [Revised: 03/21/2014] [Accepted: 03/22/2014] [Indexed: 12/18/2022]
Abstract
Autophagy is a catabolic pathway that regulates homeostasis in cells. It is an exceptional pathway of membrane trafficking. Autophagy is characterized by the formation of double-membrane vesicles; autophagosomes that are responsible for delivering damaged organelle and extra proteins to lysosome for recycling. A series of actions including environmental and genetic factors are responsible for induction of autophagy. In the past few decades, the research on autophagy has been immensely expanded because it is a vital process in maintaining cellular balance as well as deeply connected with pathogenesis of a number of diseases. The aim of this review is to present an overview of modern work on autophagy and highlight some essential genetic role in the induction of autophagy. There is an emerging need to identify, quantify, and manipulate the pathway of autophagy, due to its close relationship with a variety of developmental pathways and functions especially in cancer, diabetes, neurodegenerative disorders, and infectious diseases.
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Affiliation(s)
- M Umer Farooq Awan
- School of Life Sciences, Beijing Institute of Technology, No. 5 Zhongguancunn South Street, Beijing, 100081, People's Republic of China
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Rehman G, Shehzad A, Khan AL, Hamayun M. Role of AMP-activated protein kinase in cancer therapy. Arch Pharm (Weinheim) 2014; 347:457-68. [PMID: 24677093 DOI: 10.1002/ardp.201300402] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Revised: 01/23/2014] [Accepted: 01/31/2014] [Indexed: 11/07/2022]
Abstract
Recent advances in AMP-activated protein kinase (AMPK) as a target in cancer waxed and waned over the past decade of cancer research. AMPK is a cellular energy sensor, present in almost all eukaryotic cells. An elevated AMP/ATP ratio activates the AMPK, which in turn inhibits energy-consuming processes and induces catabolic events that generate ATP to restore the energy homeostasis inside the cell. Several reports have indicated that AMPK regulates several metabolic pathways and may be a potential therapeutic target for the treatment of cancer. Cancer cells have specific metabolic changes that differ from normal cells, and AMPK prevents the deregulated processes in cancer. AMPK may also act to inhibit tumor formation through modulation of cell growth, cell proliferation, autophagy, stress responses, and cell polarity. AMPK has been shown to inhibit mammalian target of rapamycin (mTOR) through tuberous sclerosis complex 2 (TSC2) phosphorylation and phosphatase and tensin homolog (PTEN), considered as central cell growth controller signals in diseases. In response to glucose deprivation, AMPK phosphorylates and activates p53, which induces cell cycle arrest in the G1/S phase of the cell cycle. AMPK has also been reported to block cyclin-dependent kinases through phosphorylation of p27(kip1) , promoting its stabilization and allowing cells to survive metabolic stress via induction of autophagy. Additionally, AMPK induces autophagy by phosphorylation and activation of eEF-2 kinase, and prevents the formation of new proteins. AMPK activators are also used for the treatment of type II diabetes and cancer. This review focuses on AMPK activation and its possible therapeutic role in the treatment of cancer.
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Affiliation(s)
- Gauhar Rehman
- School of Life Science, College of Natural Science, Kyungpook National University, Daegu, South Korea; Department of Zoology, Abdul Wali Khan University, Mardan, K. P. K. Pakistan
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Ashour AA, Abdel-Aziz AAH, Mansour AM, Alpay SN, Huo L, Ozpolat B. Targeting elongation factor-2 kinase (eEF-2K) induces apoptosis in human pancreatic cancer cells. Apoptosis 2014; 19:241-58. [PMID: 24193916 DOI: 10.1007/s10495-013-0927-2] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Pancreatic cancer (PaCa) is one of the most aggressive, apoptosis-resistant and currently incurable cancers with a poor survival rate. Eukaryotic elongation factor-2 kinase (eEF-2K) is an atypical kinase, whose role in PaCa survival is not yet known. Here, we show that eEF-2K is overexpressed in PaCa cells and its down-regulation induces apoptotic cell death. Rottlerin (ROT), a polyphenolic compound initially identified as a PKC-δ inhibitor, induces apoptosis and autophagy in a variety of cancer cells including PaCa cells. We demonstrated that ROT induces intrinsic apoptosis, with dissipation of mitochondrial membrane potential (ΔΨm), and stimulates extrinsic apoptosis with concomitant induction of TNF-related apoptosis inducing ligand (TRAIL) receptors, DR4 and DR5, with caspase-8 activation, in PANC-1 and MIAPaCa-2 cells. Notably, while none of these effects were dependent on PKC-δ inhibition, ROT down-regulates eEF-2K at mRNA level, and induce eEF-2K protein degradation through ubiquitin-proteasome pathway. Down-regulation of eEF-2K recapitulates the events observed after ROT treatment, while its over-expression suppressed the ROT-induced apoptosis. Furthermore, eEF-2K regulates the expression of tissue transglutaminase (TG2), an enzyme previously implicated in proliferation, drug resistance and survival of cancer cells. Inhibition of eEF-2K/TG2 axis leads to caspase-independent apoptosis which is associated with induction of apoptosis-inducing factor (AIF). Collectively, these results indicate, for the first time, that the down-regulation of eEF-2K leads to induction of intrinsic, extrinsic as well as AIF-dependent apoptosis in PaCa cells, suggesting that eEF-2K may represent an attractive therapeutic target for the future anticancer agents in PaCa.
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Affiliation(s)
- Ahmed A Ashour
- Department of Experimental Therapeutics, Unit 422, The University of Texas, M.D. Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX, 77030, USA
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Liu XY, Zhang L, Wu J, Zhou L, Ren YJ, Yang WQ, Ming ZJ, Chen B, Wang J, Zhang Y, Yang JM. Inhibition of elongation factor-2 kinase augments the antitumor activity of Temozolomide against glioma. PLoS One 2013; 8:e81345. [PMID: 24303044 PMCID: PMC3841121 DOI: 10.1371/journal.pone.0081345] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2013] [Accepted: 10/10/2013] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND Glioblastoma multiforme (GBM), the most common form of brain cancer with an average survival of less than 12 months, is a highly aggressive and fatal disease characterized by survival of glioma cells following initial treatment, invasion through the brain parenchyma and destruction of normal brain tissues, and ultimately resistance to current treatments. Temozolomide (TMZ) is commonly used chemotherapy for treatment of primary and recurrent high-grade gliomas. Nevertheless, the therapeutic outcome of TMZ is often unsatisfactory. In this study, we sought to determine whether eEF-2 kinase affected the sensitivity of glioma cells to treatment with TMZ. METHODOLOGY/PRINCIPAL FINDINGS Using RNA interference approach, a small molecule inhibitor of eEF-2 kinase, and in vitro and in vivo glioma models, we observed that inhibition of eEF-2 kinase could enhance sensitivity of glioma cells to TMZ, and that this sensitizing effect was associated with blockade of autophagy and augmentation of apoptosis caused by TMZ. CONCLUSIONS/SIGNIFICANCE These findings demonstrated that targeting eEF-2 kinase can enhance the anti-glioma activity of TMZ, and inhibitors of this kinase may be exploited as chemo-sensitizers for TMZ in treatment of malignant glioma.
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Affiliation(s)
- Xiao-yuan Liu
- Department of Pharmacology, College of Pharmaceutical Sciences, Cyrus Tang Hematology Center, Affiliated Changshu Hospital, Soochow University, Suzhou, Jiangsu, China
| | - Li Zhang
- Department of Pharmacology, College of Pharmaceutical Sciences, Cyrus Tang Hematology Center, Affiliated Changshu Hospital, Soochow University, Suzhou, Jiangsu, China
| | - JianPing Wu
- Department of Pharmacology, College of Pharmaceutical Sciences, Cyrus Tang Hematology Center, Affiliated Changshu Hospital, Soochow University, Suzhou, Jiangsu, China
| | - Lei Zhou
- Department of Pharmacology, College of Pharmaceutical Sciences, Cyrus Tang Hematology Center, Affiliated Changshu Hospital, Soochow University, Suzhou, Jiangsu, China
| | - Yi-Jie Ren
- Department of Pharmacology, College of Pharmaceutical Sciences, Cyrus Tang Hematology Center, Affiliated Changshu Hospital, Soochow University, Suzhou, Jiangsu, China
| | - Wei-Qiong Yang
- Department of Pharmacology, College of Pharmaceutical Sciences, Cyrus Tang Hematology Center, Affiliated Changshu Hospital, Soochow University, Suzhou, Jiangsu, China
| | - Zi-Jun Ming
- Department of Pharmacology, College of Pharmaceutical Sciences, Cyrus Tang Hematology Center, Affiliated Changshu Hospital, Soochow University, Suzhou, Jiangsu, China
| | - Bo Chen
- Department of Pharmacology, College of Pharmaceutical Sciences, Cyrus Tang Hematology Center, Affiliated Changshu Hospital, Soochow University, Suzhou, Jiangsu, China
| | - Jianrong Wang
- Department of Pharmacology, College of Pharmaceutical Sciences, Cyrus Tang Hematology Center, Affiliated Changshu Hospital, Soochow University, Suzhou, Jiangsu, China
| | - Yi Zhang
- Department of Pharmacology, College of Pharmaceutical Sciences, Cyrus Tang Hematology Center, Affiliated Changshu Hospital, Soochow University, Suzhou, Jiangsu, China
- * E-mail: (JMY); (YZ)
| | - Jin-Ming Yang
- Department of Pharmacology, College of Pharmaceutical Sciences, Cyrus Tang Hematology Center, Affiliated Changshu Hospital, Soochow University, Suzhou, Jiangsu, China
- Department of Pharmacology and The Penn State Hershey Cancer Institute, The Pennsylvania State University College of Medicine, Hershey, Pennsylvania, United States of America
- * E-mail: (JMY); (YZ)
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Berchtold MW, Villalobo A. The many faces of calmodulin in cell proliferation, programmed cell death, autophagy, and cancer. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2013; 1843:398-435. [PMID: 24188867 DOI: 10.1016/j.bbamcr.2013.10.021] [Citation(s) in RCA: 221] [Impact Index Per Article: 20.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2013] [Revised: 10/24/2013] [Accepted: 10/26/2013] [Indexed: 12/21/2022]
Abstract
Calmodulin (CaM) is a ubiquitous Ca(2+) receptor protein mediating a large number of signaling processes in all eukaryotic cells. CaM plays a central role in regulating a myriad of cellular functions via interaction with multiple target proteins. This review focuses on the action of CaM and CaM-dependent signaling systems in the control of vertebrate cell proliferation, programmed cell death and autophagy. The significance of CaM and interconnected CaM-regulated systems for the physiology of cancer cells including tumor stem cells, and processes required for tumor progression such as growth, tumor-associated angiogenesis and metastasis are highlighted. Furthermore, the potential targeting of CaM-dependent signaling processes for therapeutic use is discussed.
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Key Words
- (4-[3,5-bis-[2-(4-hydroxy-3-methoxy-phenyl)-ethyl]-4,5-dihydro-pyrazol-1-yl]-benzoic acid
- (4-[3,5-bis-[2-(4-hydroxy-3-methoxy-phenyl)-vinyl]-4,5-dihydro-pyrazol-1-yl]-phenyl)-(4-methyl-piperazin-1-yl)-methanone
- (−) enantiomer of dihydropyrine 3-methyl-5-3-(4,4-diphenyl-1-piperidinyl)-propyl-1,4-dihydro-2,6-dimethyl-4-(3-nitrophenyl)-piridine-3,5-dicarboxylate-hydrochloride (niguldipine)
- 1-[N,O-bis(5-isoquinolinesulfonyl)-N-methyl-l-tyrosyl]-4-phenylpiperazine
- 12-O-tetradecanoyl-phorbol-13-acetate
- 2-chloro-(ε-amino-Lys(75))-[6-(4-(N,N′-diethylaminophenyl)-1,3,5-triazin-4-yl]-CaM adduct
- 3′-(β-chloroethyl)-2′,4′-dioxo-3,5′-spiro-oxazolidino-4-deacetoxy-vinblastine
- 7,12-dimethylbenz[a]anthracene
- Apoptosis
- Autophagy
- B859-35
- CAPP(1)-CaM
- Ca(2+) binding protein
- Calmodulin
- Cancer biology
- Cell proliferation
- DMBA
- EBB
- FL-CaM
- FPCE
- HBC
- HBCP
- J-8
- KAR-2
- KN-62
- KN-93
- N-(4-aminobutyl)-2-naphthalenesulfonamide
- N-(4-aminobutyl)-5-chloro-2-naphthalenesulfonamide
- N-(6-aminohexyl)-1-naphthalenesulfonamide
- N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide
- N-8-aminooctyl-5-iodo-naphthalenesulfonamide
- N-[2-[N-(4-chlorocinnamyl)-N-methylaminomethyl]phenyl]-N-(2-hydroxyethyl)-4-methoxybenzenesulfonamide
- O-(4-ethoxyl-butyl)-berbamine
- RITC-CaM
- TA-CaM
- TFP
- TPA
- W-12
- W-13
- W-5
- W-7
- fluorescein-CaM adduct
- fluphenazine-N-2-chloroethane
- norchlorpromazine-CaM adduct
- rhodamine isothiocyanate-CaM adduct
- trifluoperazine
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Affiliation(s)
- Martin W Berchtold
- Department of Biology, University of Copenhagen, Copenhagen Biocenter 4-2-09 Ole Maaløes Vej 5, DK-2200 Copenhagen N, Denmark.
| | - Antonio Villalobo
- Instituto de Investigaciones Biomédicas, Department of Cancer Biology, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, c/Arturo Duperier 4, E-28029 Madrid, Spain.
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Schwer CI, Lehane C, Guelzow T, Zenker S, Strosing KM, Spassov S, Erxleben A, Heimrich B, Buerkle H, Humar M. Thiopental inhibits global protein synthesis by repression of eukaryotic elongation factor 2 and protects from hypoxic neuronal cell death. PLoS One 2013; 8:e77258. [PMID: 24167567 PMCID: PMC3805597 DOI: 10.1371/journal.pone.0077258] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2013] [Accepted: 08/30/2013] [Indexed: 12/27/2022] Open
Abstract
Ischemic and traumatic brain injury is associated with increased risk for death and disability. The inhibition of penumbral tissue damage has been recognized as a target for therapeutic intervention, because cellular injury evolves progressively upon ATP-depletion and loss of ion homeostasis. In patients, thiopental is used to treat refractory intracranial hypertension by reducing intracranial pressure and cerebral metabolic demands; however, therapeutic benefits of thiopental-treatment are controversially discussed. In the present study we identified fundamental neuroprotective molecular mechanisms mediated by thiopental. Here we show that thiopental inhibits global protein synthesis, which preserves the intracellular energy metabolite content in oxygen-deprived human neuronal SK-N-SH cells or primary mouse cortical neurons and thus ameliorates hypoxic cell damage. Sensitivity to hypoxic damage was restored by pharmacologic repression of eukaryotic elongation factor 2 kinase. Translational inhibition was mediated by calcium influx, activation of the AMP-activated protein kinase, and inhibitory phosphorylation of eukaryotic elongation factor 2. Our results explain the reduction of cerebral metabolic demands during thiopental treatment. Cycloheximide also protected neurons from hypoxic cell death, indicating that translational inhibitors may generally reduce secondary brain injury. In conclusion our study demonstrates that therapeutic inhibition of global protein synthesis protects neurons from hypoxic damage by preserving energy balance in oxygen-deprived cells. Molecular evidence for thiopental-mediated neuroprotection favours a positive clinical evaluation of barbiturate treatment. The chemical structure of thiopental could represent a pharmacologically relevant scaffold for the development of new organ-protective compounds to ameliorate tissue damage when oxygen availability is limited.
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Affiliation(s)
- Christian I. Schwer
- Department of Anesthesiology and Critical Care Medicine, University Medical Center Freiburg, Freiburg, Germany
| | - Cornelius Lehane
- Department of Anesthesiology and Critical Care Medicine, University Medical Center Freiburg, Freiburg, Germany
| | - Timo Guelzow
- Department of General Neurosurgery, Cellular Neurophysiology, University Medical Center Freiburg, Freiburg, Germany
| | - Simone Zenker
- Department of Anatomy and Cell Biology, University of Freiburg, Freiburg, Germany
| | - Karl M. Strosing
- Department of Anesthesiology and Critical Care Medicine, University Medical Center Freiburg, Freiburg, Germany
| | - Sashko Spassov
- Department of Anesthesiology and Critical Care Medicine, University Medical Center Freiburg, Freiburg, Germany
| | - Anika Erxleben
- Pharmaceutical Bioinformatics, Institute of Pharmaceutical Sciences, University of Freiburg, Freiburg, Germany
| | - Bernd Heimrich
- Department of Anatomy and Cell Biology, University of Freiburg, Freiburg, Germany
| | - Hartmut Buerkle
- Department of Anesthesiology and Critical Care Medicine, University Medical Center Freiburg, Freiburg, Germany
| | - Matjaz Humar
- Department of Anesthesiology and Critical Care Medicine, University Medical Center Freiburg, Freiburg, Germany
- * E-mail:
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50
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Gai Z, Zhang X, Islam M, Wang X, Li A, Yang Y, Li Y, Peng J, Hong H, Liu K. Characterization of Atg8 in lepidopteran insect cells. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2013; 84:57-77. [PMID: 23959953 DOI: 10.1002/arch.21114] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Yeast Atg8 and mammalian microtubule-associated protein light chain 3 (LC3) are landmark proteins essential for autophagy. Here the lepidopteran Atg8, a homolog of LC3, is characterized. Sequence analysis reveals that Atg8 proteins are highly conserved in lepidopteran species. The abundance of endogeous Atg8 and the ratios of Atg8 conjugation to phosphatidylethanolamine (Atg8-PE)/Atg8 are different among several lepidopteran cell lines and different tissues of Helicoverpa armigera larvae. Both the density of fluorescent pre-autophagosomal structures with GFP-Ha Atg8 and the abundance of Atg6 are positively correlated with levels of Atg8-PE in different cell lines. The mutant GFP-Atg8(G116A) has lost the function in punctual formation, suggesting that G116 is important for autophagy. Exogenous factors have significant influences on the conversion of Atg8 in lepidopteran cells. Bacillus thuringiensis enhances the degradation of Atg8 in Spodoptera litura Sl-HP cells. Atg8-PE degrades gradually with extension of amino acid starvation, and bafilomycin A1 can block the decrease through the inhibition of autophagosome fusion with lysosome. Interestingly, high pH is more effective than amino acid starvation in Bombyx mori Bme cells to induce the conversion of BmAtg8 to BmAgt8-PE. Change of the quality of fetal bovine serum in the culture medium results in alteration of the ratio of Atg8-PE/Atg8 in some lepidopteran cell lines.
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Affiliation(s)
- Zhongchao Gai
- College of Life Sciences, Central China Normal University, Wuhan City, P. R. China
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