101
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Timosenko E, Ghadbane H, Silk JD, Shepherd D, Gileadi U, Howson LJ, Laynes R, Zhao Q, Strausberg RL, Olsen LR, Taylor S, Buffa FM, Boyd R, Cerundolo V. Nutritional Stress Induced by Tryptophan-Degrading Enzymes Results in ATF4-Dependent Reprogramming of the Amino Acid Transporter Profile in Tumor Cells. Cancer Res 2016; 76:6193-6204. [PMID: 27651314 PMCID: PMC5096689 DOI: 10.1158/0008-5472.can-15-3502] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Accepted: 08/26/2016] [Indexed: 01/08/2023]
Abstract
Tryptophan degradation is an immune escape strategy shared by many tumors. However, cancer cells' compensatory mechanisms remain unclear. We demonstrate here that a shortage of tryptophan caused by expression of indoleamine 2,3-dioxygenase (IDO) and tryptophan 2,3-dioxygenase (TDO) resulted in ATF4-dependent upregulation of several amino acid transporters, including SLC1A5 and its truncated isoforms, which in turn enhanced tryptophan and glutamine uptake. Importantly, SLC1A5 failed to be upregulated in resting human T cells kept under low tryptophan conditions but was enhanced upon cognate antigen T-cell receptor engagement. Our results highlight key differences in the ability of tumor and T cells to adapt to tryptophan starvation and provide important insights into the poor prognosis of tumors coexpressing IDO and SLC1A5. Cancer Res; 76(21); 6193-204. ©2016 AACR.
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Affiliation(s)
- Elina Timosenko
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
| | - Hemza Ghadbane
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
| | - Jonathan D Silk
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
| | - Dawn Shepherd
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
| | - Uzi Gileadi
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
| | - Lauren J Howson
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
| | - Robert Laynes
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Qi Zhao
- Ludwig Cancer Research, New York, New York
| | | | - Lars R Olsen
- Center for Biological Sequence Analysis, Department of Systems Biology, Technical University of Denmark, Lyngby, Denmark
| | - Stephen Taylor
- The Computational Biology Research Group (CBRG), Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
| | - Francesca M Buffa
- Department of Oncology, Old Road Campus Research Building, University of Oxford, Oxford, United Kingdom
| | - Richard Boyd
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Vincenzo Cerundolo
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom.
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102
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Xiao D, Ren P, Su H, Yue M, Xiu R, Hu Y, Liu H, Qing G. Myc promotes glutaminolysis in human neuroblastoma through direct activation of glutaminase 2. Oncotarget 2016; 6:40655-66. [PMID: 26528759 PMCID: PMC4747359 DOI: 10.18632/oncotarget.5821] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2015] [Accepted: 09/23/2015] [Indexed: 01/02/2023] Open
Abstract
Deamidation of glutamine to glutamate by glutaminase 1 (GLS1, also called GLS) and GLS2 is an essential step in both glutaminolysis and glutathione (GSH) biosynthesis. However, mechanisms whereby cancer cells regulate glutamine catabolism remains largely unknown. We report here that N-Myc, an essential Myc family member, promotes conversion of glutamine to glutamate in MYCN-amplified neuroblastoma cells by directly activating GLS2, but not GLS1, transcription. Abrogation of GLS2 function profoundly inhibited glutaminolysis, which resulted in feedback inhibition of aerobic glycolysis likely due to thioredoxin-interacting protein (TXNIP) activation, dramatically decreasing cell proliferation and survival in vitro and in vivo. Moreover, elevated GLS2 expression is significantly elevated in MYCN-amplified neuroblastomas in comparison with non-amplified ones, correlating with unfavorable patient survival. In aggregate, these results reveal a novel mechanism deciphering context-dependent regulation of metabolic heterogeneities, uncovering a previously unsuspected link between Myc, GLS2 and tumor metabolism.
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Affiliation(s)
- Daibiao Xiao
- School of Basic Medicine, Tongji Medical College, Huazhong University of Science & Technology, Wuhan 430030, China
| | - Ping Ren
- Department of Pharmacology, School of Pharmacy, Hubei University of Science & Technology, Xianning 437100, China
| | - Hexiu Su
- School of Pharmacy, Tongji Medical College, Huazhong University of Science & Technology, Wuhan 430030, China
| | - Ming Yue
- School of Basic Medicine, Tongji Medical College, Huazhong University of Science & Technology, Wuhan 430030, China
| | - Ruijuan Xiu
- School of Basic Medicine, Tongji Medical College, Huazhong University of Science & Technology, Wuhan 430030, China
| | - Yufeng Hu
- School of Pharmacy, Tongji Medical College, Huazhong University of Science & Technology, Wuhan 430030, China
| | - Hudan Liu
- School of Pharmacy, Tongji Medical College, Huazhong University of Science & Technology, Wuhan 430030, China.,Medical Research Institute, Wuhan University, Wuhan 430071, China
| | - Guoliang Qing
- School of Basic Medicine, Tongji Medical College, Huazhong University of Science & Technology, Wuhan 430030, China.,Medical Research Institute, Wuhan University, Wuhan 430071, China
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103
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DEPTOR is a direct NOTCH1 target that promotes cell proliferation and survival in T-cell leukemia. Oncogene 2016; 36:1038-1047. [PMID: 27593934 DOI: 10.1038/onc.2016.275] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Revised: 06/20/2016] [Accepted: 06/27/2016] [Indexed: 12/21/2022]
Abstract
Aberrant activation of NOTCH1 signaling plays a vital role in the pathogenesis of T-cell acute lymphoblastic leukemia (T-ALL). Yet the molecular events downstream of NOTCH1 that drive T-cell leukemogenesis remain incompletely understood. Starting from genome-wide gene-expression profiling to seek important NOTCH1 transcriptional targets, we identified DEP-domain containing mTOR-interacting protein (DEPTOR), which was previously shown to be important in multiple myeloma but remains functionally unclear in other hematological malignancies. Mechanistically, we demonstrated NOTCH1 directly bound to and activated the human DEPTOR promoter in T-ALL cells. DEPTOR depletion abolished cellular proliferation, attenuated glycolytic metabolism and enhanced cell death, while ectopically expressed DEPTOR significantly promoted cell growth and glycolysis. We further showed that DEPTOR depletion inhibited while its overexpression enhanced AKT activation in T-ALL cells. Importantly, AKT inhibition completely abrogated DEPTOR-mediated cell growth advantages. Moreover, DEPTOR depletion in a human T-ALL xenograft model significantly delayed T-ALL onset and caused a substantial decrease of AKT activation in leukemic blasts. We thus reveal a novel mechanism involved in NOTCH1-driven leukemogenesis, identifying the transcriptional control of DEPTOR and its regulation of AKT as additional key elements of the leukemogenic program activated by NOTCH1.
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104
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Li Y, Li X, Li X, Zhong Y, Ji Y, Yu D, Zhang M, Wen JG, Zhang H, Goscinski MA, Nesland JM, Suo Z. PDHA1 gene knockout in prostate cancer cells results in metabolic reprogramming towards greater glutamine dependence. Oncotarget 2016; 7:53837-53852. [PMID: 27462778 PMCID: PMC5288225 DOI: 10.18632/oncotarget.10782] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Accepted: 07/10/2016] [Indexed: 12/22/2022] Open
Abstract
Alternative pathways of metabolism endowed cancer cells with metabolic stress. Inhibiting the related compensatory pathways might achieve synergistic anticancer results. This study demonstrated that pyruvate dehydrogenase E1α gene knockout (PDHA1 KO) resulted in alterations in tumor cell metabolism by rendering the cells with increased expression of glutaminase1 (GLS1) and glutamate dehydrogenase1 (GLUD1), leading to an increase in glutamine-dependent cell survival. Deprivation of glutamine induced cell growth inhibition, increased reactive oxygen species and decreased ATP production. Pharmacological blockade of the glutaminolysis pathway resulted in massive tumor cells apoptosis and dysfunction of ROS scavenge in the LNCaP PDHA1 KO cells. Further examination of the key glutaminolysis enzymes in human prostate cancer samples also revealed that higher levels of GLS1 and GLUD1 expression were significantly associated with aggressive clinicopathological features and poor clinical outcome. These insights supply evidence that glutaminolysis plays a compensatory role for cell survival upon alternative energy metabolism and targeting the glutamine anaplerosis of energy metabolism via GLS1 and GLUD1 in cancer cells may offer a potential novel therapeutic strategy.
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Affiliation(s)
- Yaqing Li
- Department of Oncology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan Province, China
- Department of Pathology, The Norwegian Radium Hospital, Oslo University Hospital, University of Oslo, Montebello, Oslo, Norway
- Department of Pathology, The Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Montebello, Oslo, Norway
| | - Xiaoran Li
- Department of Pathology, The Norwegian Radium Hospital, Oslo University Hospital, University of Oslo, Montebello, Oslo, Norway
- Department of Pathology, The Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Montebello, Oslo, Norway
| | - Xiaoli Li
- Department of Oncology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan Province, China
- Department of Pathology, The Norwegian Radium Hospital, Oslo University Hospital, University of Oslo, Montebello, Oslo, Norway
| | - Yali Zhong
- Department of Oncology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan Province, China
| | - Yasai Ji
- Department of Oncology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan Province, China
| | - Dandan Yu
- Department of Oncology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan Province, China
- Department of Pathology, The Norwegian Radium Hospital, Oslo University Hospital, University of Oslo, Montebello, Oslo, Norway
| | - Mingzhi Zhang
- Department of Oncology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan Province, China
| | - Jian-Guo Wen
- Institute of Clinical Medicine, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan Province, China
| | - Hongquan Zhang
- Department of Anatomy, Histology and Embryology, Peking University Health Science Center, Peking University, Beijing, China
| | - Mariusz Adam Goscinski
- Department of Surgery, the Norwegian Radium Hospital, Oslo University Hospital, University of Oslo, Oslo, Norway
| | - Jahn M. Nesland
- Department of Pathology, The Norwegian Radium Hospital, Oslo University Hospital, University of Oslo, Montebello, Oslo, Norway
- Department of Pathology, The Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Montebello, Oslo, Norway
| | - Zhenhe Suo
- Department of Oncology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan Province, China
- Department of Pathology, The Norwegian Radium Hospital, Oslo University Hospital, University of Oslo, Montebello, Oslo, Norway
- Department of Pathology, The Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Montebello, Oslo, Norway
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105
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Xu X, Li J, Sun X, Guo Y, Chu D, Wei L, Li X, Yang G, Liu X, Yao L, Zhang J, Shen L. Tumor suppressor NDRG2 inhibits glycolysis and glutaminolysis in colorectal cancer cells by repressing c-Myc expression. Oncotarget 2016; 6:26161-76. [PMID: 26317652 PMCID: PMC4694893 DOI: 10.18632/oncotarget.4544] [Citation(s) in RCA: 70] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2015] [Accepted: 07/08/2015] [Indexed: 12/13/2022] Open
Abstract
Cancer cells use glucose and glutamine as the major sources of energy and precursor intermediates, and enhanced glycolysis and glutamimolysis are the major hallmarks of metabolic reprogramming in cancer. Oncogene activation and tumor suppressor gene inactivation alter multiple intracellular signaling pathways that affect glycolysis and glutaminolysis. N-Myc downstream regulated gene 2 (NDRG2) is a tumor suppressor gene inhibiting cancer growth, metastasis and invasion. However, the role and molecular mechanism of NDRG2 in cancer metabolism remains unclear. In this study, we discovered the role of the tumor suppressor gene NDRG2 in aerobic glycolysis and glutaminolysis of cancer cells. NDRG2 inhibited glucose consumption and lactate production, glutamine consumption and glutamate production in colorectal cancer cells. Analysis of glucose transporters and the catalytic enzymes involved in glycolysis revealed that glucose transporter 1 (GLUT1), hexokinase 2 (HK2), pyruvate kinase M2 isoform (PKM2) and lactate dehydrogenase A (LDHA) was significantly suppressed by NDRG2. Analysis of glutamine transporter and the catalytic enzymes involved in glutaminolysis revealed that glutamine transporter ASC amino-acid transporter 2 (ASCT2) and glutaminase 1 (GLS1) was also significantly suppressed by NDRG2. Transcription factor c-Myc mediated inhibition of glycolysis and glutaminolysis by NDRG2. More importantly, NDRG2 inhibited the expression of c-Myc by suppressing the expression of β-catenin, which can transcriptionally activate C-MYC gene in nucleus. In addition, the growth and proliferation of colorectal cancer cells were suppressed significantly by NDRG2 through inhibition of glycolysis and glutaminolysis. Taken together, these findings indicate that NDRG2 functions as an essential regulator in glycolysis and glutaminolysis via repression of c-Myc, and acts as a suppressor of carcinogenesis through coordinately targeting glucose and glutamine transporter, multiple catalytic enzymes involved in glycolysis and glutaminolysis, which fuels the bioenergy and biomaterials needed for cancer proliferation and progress.
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Affiliation(s)
- Xinyuan Xu
- The State Key Laboratory of Cancer Biology, Department of Biochemistry and Molecular Biology, The Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Jianying Li
- The State Key Laboratory of Cancer Biology, Department of Biochemistry and Molecular Biology, The Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Xiang Sun
- Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Yan Guo
- The State Key Laboratory of Cancer Biology, Department of Biochemistry and Molecular Biology, The Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Dake Chu
- The State Key Laboratory of Cancer Biology, Department of Gastrointestinal Surgery, Xijing Hospital of Digestive Diseases, The Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Li Wei
- Department of Obstetrics and Gynecology, Xijing Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Xia Li
- The State Key Laboratory of Cancer Biology, Department of Biochemistry and Molecular Biology, The Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Guodong Yang
- The State Key Laboratory of Cancer Biology, Department of Biochemistry and Molecular Biology, The Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Xinping Liu
- The State Key Laboratory of Cancer Biology, Department of Biochemistry and Molecular Biology, The Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Libo Yao
- The State Key Laboratory of Cancer Biology, Department of Biochemistry and Molecular Biology, The Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Jian Zhang
- The State Key Laboratory of Cancer Biology, Department of Biochemistry and Molecular Biology, The Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Lan Shen
- The State Key Laboratory of Cancer Biology, Department of Biochemistry and Molecular Biology, The Fourth Military Medical University, Xi'an, Shaanxi, China
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106
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van Geldermalsen M, Wang Q, Nagarajah R, Marshall AD, Thoeng A, Gao D, Ritchie W, Feng Y, Bailey CG, Deng N, Harvey K, Beith JM, Selinger CI, O'Toole SA, Rasko JEJ, Holst J. ASCT2/SLC1A5 controls glutamine uptake and tumour growth in triple-negative basal-like breast cancer. Oncogene 2016; 35:3201-8. [PMID: 26455325 PMCID: PMC4914826 DOI: 10.1038/onc.2015.381] [Citation(s) in RCA: 404] [Impact Index Per Article: 50.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2015] [Revised: 09/01/2015] [Accepted: 09/04/2015] [Indexed: 12/31/2022]
Abstract
Alanine, serine, cysteine-preferring transporter 2 (ASCT2; SLC1A5) mediates uptake of glutamine, a conditionally essential amino acid in rapidly proliferating tumour cells. Uptake of glutamine and subsequent glutaminolysis is critical for activation of the mTORC1 nutrient-sensing pathway, which regulates cell growth and protein translation in cancer cells. This is of particular interest in breast cancer, as glutamine dependence is increased in high-risk breast cancer subtypes. Pharmacological inhibitors of ASCT2-mediated transport significantly reduced glutamine uptake in human breast cancer cell lines, leading to the suppression of mTORC1 signalling, cell growth and cell cycle progression. Notably, these effects were subtype-dependent, with ASCT2 transport critical only for triple-negative (TN) basal-like breast cancer cell growth compared with minimal effects in luminal breast cancer cells. Both stable and inducible shRNA-mediated ASCT2 knockdown confirmed that inhibiting ASCT2 function was sufficient to prevent cellular proliferation and induce rapid cell death in TN basal-like breast cancer cells, but not in luminal cells. Using a bioluminescent orthotopic xenograft mouse model, ASCT2 expression was then shown to be necessary for both successful engraftment and growth of HCC1806 TN breast cancer cells in vivo. Lower tumoral expression of ASCT2 conferred a significant survival advantage in xenografted mice. These responses remained intact in primary breast cancers, where gene expression analysis showed high expression of ASCT2 and glutamine metabolism-related genes, including GLUL and GLS, in a cohort of 90 TN breast cancer patients, as well as correlations with the transcriptional regulators, MYC and ATF4. This study provides preclinical evidence for the feasibility of novel therapies exploiting ASCT2 transporter activity in breast cancer, particularly in the high-risk basal-like subgroup of TN breast cancer where there is not only high expression of ASCT2, but also a marked reliance on its activity for sustained cellular proliferation.
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Affiliation(s)
- M van Geldermalsen
- Origins of Cancer Program, Centenary Institute, Camperdown, New South Wales, Australia
- Gene and Stem Cell Therapy Program, Centenary Institute, Camperdown, New South Wales, Australia
- Sydney Medical School, University of Sydney, Sydney, New South Wales, Australia
| | - Q Wang
- Origins of Cancer Program, Centenary Institute, Camperdown, New South Wales, Australia
- Gene and Stem Cell Therapy Program, Centenary Institute, Camperdown, New South Wales, Australia
- Sydney Medical School, University of Sydney, Sydney, New South Wales, Australia
| | - R Nagarajah
- Origins of Cancer Program, Centenary Institute, Camperdown, New South Wales, Australia
- Gene and Stem Cell Therapy Program, Centenary Institute, Camperdown, New South Wales, Australia
- Sydney Medical School, University of Sydney, Sydney, New South Wales, Australia
| | - A D Marshall
- Gene and Stem Cell Therapy Program, Centenary Institute, Camperdown, New South Wales, Australia
- Sydney Medical School, University of Sydney, Sydney, New South Wales, Australia
| | - A Thoeng
- Gene and Stem Cell Therapy Program, Centenary Institute, Camperdown, New South Wales, Australia
- Sydney Medical School, University of Sydney, Sydney, New South Wales, Australia
| | - D Gao
- Gene and Stem Cell Therapy Program, Centenary Institute, Camperdown, New South Wales, Australia
- Sydney Medical School, University of Sydney, Sydney, New South Wales, Australia
- Bioinformatics Laboratory, Centenary Institute, Camperdown, New South Wales, Australia
| | - W Ritchie
- Gene and Stem Cell Therapy Program, Centenary Institute, Camperdown, New South Wales, Australia
- Sydney Medical School, University of Sydney, Sydney, New South Wales, Australia
- Bioinformatics Laboratory, Centenary Institute, Camperdown, New South Wales, Australia
| | - Y Feng
- Gene and Stem Cell Therapy Program, Centenary Institute, Camperdown, New South Wales, Australia
- Sydney Medical School, University of Sydney, Sydney, New South Wales, Australia
| | - C G Bailey
- Gene and Stem Cell Therapy Program, Centenary Institute, Camperdown, New South Wales, Australia
- Sydney Medical School, University of Sydney, Sydney, New South Wales, Australia
| | - N Deng
- The Kinghorn Cancer Centre and Cancer Research Program, Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia
- St Vincent's Clinical School, Faculty of Medicine, University of New South Wales, Sydney, New South Wales, Australia
| | - K Harvey
- The Kinghorn Cancer Centre and Cancer Research Program, Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia
- Department of Tissue Pathology and Diagnostic Oncology, Royal Prince Alfred Hospital, Camperdown, New South Wales, Australia
| | - J M Beith
- Sydney Medical School, University of Sydney, Sydney, New South Wales, Australia
- Department of Medical Oncology, Chris O'Brien Lifehouse, Camperdown, New South Wales, Australia
| | - C I Selinger
- Department of Tissue Pathology and Diagnostic Oncology, Royal Prince Alfred Hospital, Camperdown, New South Wales, Australia
| | - S A O'Toole
- Sydney Medical School, University of Sydney, Sydney, New South Wales, Australia
- The Kinghorn Cancer Centre and Cancer Research Program, Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia
- Department of Tissue Pathology and Diagnostic Oncology, Royal Prince Alfred Hospital, Camperdown, New South Wales, Australia
| | - J E J Rasko
- Gene and Stem Cell Therapy Program, Centenary Institute, Camperdown, New South Wales, Australia
- Sydney Medical School, University of Sydney, Sydney, New South Wales, Australia
- Cell and Molecular Therapies, Royal Prince Alfred Hospital, Sydney, New South Wales, Australia
| | - J Holst
- Origins of Cancer Program, Centenary Institute, Camperdown, New South Wales, Australia
- Gene and Stem Cell Therapy Program, Centenary Institute, Camperdown, New South Wales, Australia
- Sydney Medical School, University of Sydney, Sydney, New South Wales, Australia
- Associate, Origins of Cancer Program, Centenary Institute, Locked Bag 6, Newtown, New South Wales 2042, Australia. E-mail:
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107
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Ye Q, Jiang J, Zhan G, Yan W, Huang L, Hu Y, Su H, Tong Q, Yue M, Li H, Yao G, Zhang Y, Liu H. Small molecule activation of NOTCH signaling inhibits acute myeloid leukemia. Sci Rep 2016; 6:26510. [PMID: 27211848 PMCID: PMC4876435 DOI: 10.1038/srep26510] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Accepted: 05/03/2016] [Indexed: 01/04/2023] Open
Abstract
Aberrant activation of the NOTCH signaling pathway is crucial for the onset and progression of T cell leukemia. Yet recent studies also suggest a tumor suppressive role of NOTCH signaling in acute myeloid leukemia (AML) and reactivation of this pathway offers an attractive opportunity for anti-AML therapies. N-methylhemeanthidine chloride (NMHC) is a novel Amaryllidaceae alkaloid that we previously isolated from Zephyranthes candida, exhibiting inhibitory activities in a variety of cancer cells, particularly those from AML. Here, we report NMHC not only selectively inhibits AML cell proliferation in vitro but also hampers tumor development in a human AML xenograft model. Genome-wide gene expression profiling reveals that NMHC activates the NOTCH signaling. Combination of NMHC and recombinant human NOTCH ligand DLL4 achieves a remarkable synergistic effect on NOTCH activation. Moreover, pre-inhibition of NOTCH by overexpression of dominant negative MAML alleviates NMHC-mediated cytotoxicity in AML. Further mechanistic analysis using structure-based molecular modeling as well as biochemical assays demonstrates that NMHC docks in the hydrophobic cavity within the NOTCH1 negative regulatory region (NRR), thus promoting NOTCH1 proteolytic cleavage. Our findings thus establish NMHC as a potential NOTCH agonist that holds great promises for future development as a novel agent beneficial to patients with AML.
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Affiliation(s)
- Qi Ye
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.,Department of Pharmacy, Wuhan Children's Hospital, Wuhan, 430016, China
| | - Jue Jiang
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Guanqun Zhan
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Wanyao Yan
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Liang Huang
- Department of Hematology, Tongji Hospital, Wuhan, 430030, China
| | - Yufeng Hu
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Hexiu Su
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Qingyi Tong
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Ming Yue
- School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Hua Li
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Guangmin Yao
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Yonghui Zhang
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Hudan Liu
- Medical Research Institute, Wuhan University, Wuhan, 430071, China
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108
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Selwan EM, Finicle BT, Kim SM, Edinger AL. Attacking the supply wagons to starve cancer cells to death. FEBS Lett 2016; 590:885-907. [PMID: 26938658 DOI: 10.1002/1873-3468.12121] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Revised: 02/10/2016] [Accepted: 02/29/2016] [Indexed: 12/14/2022]
Abstract
The constitutive anabolism of cancer cells not only supports proliferation but also addicts tumor cells to a steady influx of exogenous nutrients. Limiting access to metabolic substrates could be an effective and selective means to block cancer growth. In this review, we define the pathways by which cancer cells acquire the raw materials for anabolism, highlight the actionable proteins in each pathway, and discuss the status of therapeutic interventions that disrupt nutrient acquisition. Critical open questions to be answered before apical metabolic inhibitors can be successfully and safely deployed in the clinic are also outlined. In summary, recent studies provide strong support that substrate limitation is a powerful therapeutic strategy to effectively, and safely, starve cancer cells to death.
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Affiliation(s)
- Elizabeth M Selwan
- Department of Developmental and Cell Biology, University of California Irvine, CA, USA
| | - Brendan T Finicle
- Department of Developmental and Cell Biology, University of California Irvine, CA, USA
| | - Seong M Kim
- Department of Developmental and Cell Biology, University of California Irvine, CA, USA
| | - Aimee L Edinger
- Department of Developmental and Cell Biology, University of California Irvine, CA, USA
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109
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Kim-Muller JY, Kim YJR, Fan J, Zhao S, Banks AS, Prentki M, Accili D. FoxO1 Deacetylation Decreases Fatty Acid Oxidation in β-Cells and Sustains Insulin Secretion in Diabetes. J Biol Chem 2016; 291:10162-72. [PMID: 26984405 DOI: 10.1074/jbc.m115.705608] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Indexed: 11/06/2022] Open
Abstract
Pancreatic β-cell dysfunction contributes to onset and progression of type 2 diabetes. In this state β-cells become metabolically inflexible, losing the ability to select between carbohydrates and lipids as substrates for mitochondrial oxidation. These changes lead to β-cell dedifferentiation. We have proposed that FoxO proteins are activated through deacetylation-dependent nuclear translocation to forestall the progression of these abnormalities. However, how deacetylated FoxO exert their actions remains unclear. To address this question, we analyzed islet function in mice homozygous for knock-in alleles encoding deacetylated FoxO1 (6KR). Islets expressing 6KR mutant FoxO1 have enhanced insulin secretion in vivo and ex vivo and decreased fatty acid oxidation ex vivo Remarkably, the gene expression signature associated with FoxO1 deacetylation differs from wild type by only ∼2% of the >4000 genes regulated in response to re-feeding. But this narrow swath includes key genes required for β-cell identity, lipid metabolism, and mitochondrial fatty acid and solute transport. The data support the notion that deacetylated FoxO1 protects β-cell function by limiting mitochondrial lipid utilization and raise the possibility that inhibition of fatty acid oxidation in β-cells is beneficial to diabetes treatment.
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Affiliation(s)
- Ja Young Kim-Muller
- From the Naomi Berrie Diabetes Center, Department of Medicine, Columbia University, New York, New York 10032, Merck Research Laboratories, Boston, Massachusetts 02816
| | - Young Jung R Kim
- From the Naomi Berrie Diabetes Center, Department of Medicine, Columbia University, New York, New York 10032
| | - Jason Fan
- From the Naomi Berrie Diabetes Center, Department of Medicine, Columbia University, New York, New York 10032
| | - Shangang Zhao
- Molecular Nutrition Unit and Montreal Diabetes Research Center at the CRCHUM and Departments of Nutrition and Biochemistry and Department of Molecular Medicine, Université de Montréal, Montréal, H2X 0A9, Canada, and
| | | | - Marc Prentki
- Molecular Nutrition Unit and Montreal Diabetes Research Center at the CRCHUM and Departments of Nutrition and Biochemistry and Department of Molecular Medicine, Université de Montréal, Montréal, H2X 0A9, Canada, and
| | - Domenico Accili
- From the Naomi Berrie Diabetes Center, Department of Medicine, Columbia University, New York, New York 10032,
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110
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Abstract
Cancer is a disease characterized by uncontrolled growth. Metabolic demands to sustain rapid proliferation must be compelling since aerobic glycolysis is the first as well as the most commonly shared characteristic of cancer. During the last decade, the significance of metabolic reprogramming of cancer has been at the center of attention. Nonetheless, despite all the knowledge gained on cancer biology, the field is not able to reach agreement on the issue of mitochondria: Are damaged mitochondria the cause for aerobic glycolysis in cancer? Warburg proposed the damaged mitochondria theory over 80 years ago; the field has been testing the theory equally long. In this review, we will discuss alterations in metabolic fluxes of cancer cells, and provide an opinion on the damaged mitochondria theory.
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Affiliation(s)
- Aekyong Kim
- School of Pharmacy, Catholic University of Daegu, Gyeongbuk, Korea
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111
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Bhutia YD, Ganapathy V. Glutamine transporters in mammalian cells and their functions in physiology and cancer. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2015; 1863:2531-9. [PMID: 26724577 DOI: 10.1016/j.bbamcr.2015.12.017] [Citation(s) in RCA: 197] [Impact Index Per Article: 21.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Revised: 12/19/2015] [Accepted: 12/22/2015] [Indexed: 01/17/2023]
Abstract
The SLC (solute carrier)-type transporters (~400 in number) in mammalian cells consist of 52 distinct gene families, grouped solely based on the amino acid sequence (primary structure) of the transporter proteins and not on their transport function. Among them are the transporters for amino acids. Fourteen of them, capable of transporting glutamine across the plasma membrane, are found in four families: SLC1, SLC6, SLC7, and SLC38. However, it is generally thought that the members of the SLC38 family are the principal transporters for glutamine. Some of the glutamine transporters are obligatory exchangers whereas some function as active transporters in one direction. While most glutamine transporters mediate the influx of the amino acid into cells, some actually mediate the efflux of the amino acid out of the cells. Glutamine transporters play important roles in a variety of tissues, including the liver, brain, kidney, and placenta, as clearly evident from the biological and biochemical phenotypes resulting from the deletion of specific glutamine transporters in mice. Owing to the obligatory role of glutamine in growth and proliferation of tumor cells, there is increasing attention on glutamine transporters in cancer biology as potential drug targets for cancer treatment. Selective blockers of certain glutamine transporters might be effective in preventing the entry of glutamine and other important amino acids into tumor cells, thus essentially starving these cells to death. This could represent the beginning of a new era in the discovery of novel anticancer drugs with a previously unexplored mode of action. This article is part of a Special Issue entitled: Mitochondrial Channels edited by Pierre Sonveaux, Pierre Maechler and Jean-Claude Martinou.
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Affiliation(s)
- Yangzom D Bhutia
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA
| | - Vadivel Ganapathy
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA.
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112
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Liu Y, Yang L, An H, Chang Y, Zhang W, Zhu Y, Xu L, Xu J. High expression of Solute Carrier Family 1, member 5 (SLC1A5) is associated with poor prognosis in clear-cell renal cell carcinoma. Sci Rep 2015; 5:16954. [PMID: 26599282 PMCID: PMC4657035 DOI: 10.1038/srep16954] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Accepted: 10/21/2015] [Indexed: 12/21/2022] Open
Abstract
Solute Carrier Family 1, member 5 (SLC1A5), also named as ASCT2, a major glutamine transporter, is highly expressed in various malignancies and plays a critical role in the transformation, growth and survival of cancer cells. The aim of this study was to assess the clinical significance of SLC1A5 in patients with clear-cell renal cell carcinoma (ccRCC). SLC1A5 expression was evaluated by immunohistochemistry on tissue microarrays. Kaplan-Meier method was conducted to compare survival curves. Univariate and multivariate Cox regression models were applied to assess the impact of prognostic factors on overall survival (OS). A nomogram was then constructed on the basis of the independent prognosticators identified on multivariate analysis. The predictive ability of the models was compared using Receiver operating characteristic (ROC) analysis. Our data indicated that high expression of SLC1A5 was significantly associated with advanced TNM stage, higher Fuhrman grade and shorter OS in ccRCC patients. Multivariate analysis confirmed that SLC1A5 was an independent prognosticator for OS. A nomogram integrating SLC1A5 and other independent prognosticators was constructed, which showed a better prognostic value for OS than TNM staging system. In conclusion, high SLC1A5 expression is an independent predictor of adverse clinical outcome in ccRCC patients after surgery.
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Affiliation(s)
- Yidong Liu
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai, China
| | - Liu Yang
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai, China
| | - Huimin An
- Department of Urology, Shanghai Cancer Center, Fudan University, Shanghai, China
| | - Yuan Chang
- Department of Urology, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Weijuan Zhang
- Department of Immunology, School of Basic Medical Sciences, Fudan University, Shanghai, China
| | - Yu Zhu
- Department of Urology, Shanghai Cancer Center, Fudan University, Shanghai, China
| | - Le Xu
- Department of Urology, Ruijin Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China
| | - Jiejie Xu
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai, China
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113
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Colas C, Grewer C, Otte NJ, Gameiro A, Albers T, Singh K, Shere H, Bonomi M, Holst J, Schlessinger A. Ligand Discovery for the Alanine-Serine-Cysteine Transporter (ASCT2, SLC1A5) from Homology Modeling and Virtual Screening. PLoS Comput Biol 2015; 11:e1004477. [PMID: 26444490 PMCID: PMC4596572 DOI: 10.1371/journal.pcbi.1004477] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Accepted: 07/23/2015] [Indexed: 12/20/2022] Open
Abstract
The Alanine-Serine-Cysteine transporter ASCT2 (SLC1A5) is a membrane protein that transports neutral amino acids into cells in exchange for outward movement of intracellular amino acids. ASCT2 is highly expressed in peripheral tissues such as the lung and intestines where it contributes to the homeostasis of intracellular concentrations of neutral amino acids. ASCT2 also plays an important role in the development of a variety of cancers such as melanoma by transporting amino acid nutrients such as glutamine into the proliferating tumors. Therefore, ASCT2 is a key drug target with potentially great pharmacological importance. Here, we identify seven ASCT2 ligands by computational modeling and experimental testing. In particular, we construct homology models based on crystallographic structures of the aspartate transporter GltPh in two different conformations. Optimization of the models' binding sites for protein-ligand complementarity reveals new putative pockets that can be targeted via structure-based drug design. Virtual screening of drugs, metabolites, fragments-like, and lead-like molecules from the ZINC database, followed by experimental testing of 14 top hits with functional measurements using electrophysiological methods reveals seven ligands, including five activators and two inhibitors. For example, aminooxetane-3-carboxylate is a more efficient activator than any other known ASCT2 natural or unnatural substrate. Furthermore, two of the hits inhibited ASCT2 mediated glutamine uptake and proliferation of a melanoma cancer cell line. Our results improve our understanding of how substrate specificity is determined in amino acid transporters, as well as provide novel scaffolds for developing chemical tools targeting ASCT2, an emerging therapeutic target for cancer and neurological disorders.
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Affiliation(s)
- Claire Colas
- Department of Pharmacology and Systems Therapeutics, Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
| | - Christof Grewer
- Department of Chemistry, Binghamton University, Binghamton, New York, United States of America
| | - Nicholas James Otte
- Origins of Cancer Laboratory Centenary Program, Camperdown, Australia
- Sydney Medical School, University of Sydney, Sydney, Australia
| | - Armanda Gameiro
- Department of Chemistry, Binghamton University, Binghamton, New York, United States of America
| | - Thomas Albers
- Department of Chemistry, Binghamton University, Binghamton, New York, United States of America
| | - Kurnvir Singh
- Department of Chemistry, Binghamton University, Binghamton, New York, United States of America
| | - Helen Shere
- Department of Pharmacology and Systems Therapeutics, Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
| | | | - Jeff Holst
- Origins of Cancer Laboratory Centenary Program, Camperdown, Australia
- Sydney Medical School, University of Sydney, Sydney, Australia
- * E-mail: (JH); (AS)
| | - Avner Schlessinger
- Department of Pharmacology and Systems Therapeutics, Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
- * E-mail: (JH); (AS)
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114
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Gan L, Xiu R, Ren P, Yue M, Su H, Guo G, Xiao D, Yu J, Jiang H, Liu H, Hu G, Qing G. Metabolic targeting of oncogene MYC by selective activation of the proton-coupled monocarboxylate family of transporters. Oncogene 2015; 35:3037-48. [PMID: 26434591 DOI: 10.1038/onc.2015.360] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2015] [Revised: 08/14/2015] [Accepted: 08/24/2015] [Indexed: 12/23/2022]
Abstract
Deregulation of the MYC oncogene produces Myc protein that regulates multiple aspects of cancer cell metabolism, contributing to the acquisition of building blocks essential for cancer cell growth and proliferation. Therefore, disabling Myc function represents an attractive therapeutic option for cancer treatment. However, pharmacological strategies capable of directly targeting Myc remain elusive. Here, we identified that 3-bromopyruvate (3-BrPA), a drug candidate that primarily inhibits glycolysis, preferentially induced massive cell death in human cancer cells overexpressing the MYC oncogene, in vitro and in vivo, without appreciable effects on those exhibiting low MYC levels. Importantly, pharmacological inhibition of glutamine metabolism synergistically potentiated the synthetic lethal targeting of MYC by 3-BrPA due in part to the metabolic disturbance caused by this combination. Mechanistically, we identified that the proton-coupled monocarboxylate transporter 1 (MCT1) and MCT2, which enable efficient 3-BrPA uptake by cancer cells, were selectively activated by Myc. Two regulatory mechanisms were involved: first, Myc directly activated MCT1 and MCT2 transcription by binding to specific recognition sites of both genes; second, Myc transcriptionally repressed miR29a and miR29c, resulting in enhanced expression of their target protein MCT1. Of note, expressions of MCT1 and MCT2 were each significantly elevated in MYCN-amplified neuroblastomas and C-MYC-overexpressing lymphomas than in tumors without MYC overexpression, correlating with poor prognosis and unfavorable patient survival. These results identify a novel mechanism by which Myc sensitizes cells to metabolic inhibitors and validate 3-BrPA as potential Myc-selective cancer therapeutics.
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Affiliation(s)
- L Gan
- Department of Oncology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People's Republic of China.,School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People's Republic of China
| | - R Xiu
- School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People's Republic of China
| | - P Ren
- School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People's Republic of China
| | - M Yue
- School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People's Republic of China
| | - H Su
- School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People's Republic of China
| | - G Guo
- School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People's Republic of China
| | - D Xiao
- School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People's Republic of China
| | - J Yu
- Key Laboratory of Systems Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, People's Republic of China
| | - H Jiang
- Key Laboratory of Systems Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, People's Republic of China
| | - H Liu
- School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People's Republic of China
| | - G Hu
- Department of Oncology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People's Republic of China
| | - G Qing
- School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People's Republic of China.,Medical Research Institute, Wuhan University, Wuhan, People's Republic of China
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115
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Corrigendum. J Pathol 2015; 237:133. [DOI: 10.1002/path.4570] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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116
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Sanchez EL, Carroll PA, Thalhofer AB, Lagunoff M. Latent KSHV Infected Endothelial Cells Are Glutamine Addicted and Require Glutaminolysis for Survival. PLoS Pathog 2015. [PMID: 26197457 PMCID: PMC4510438 DOI: 10.1371/journal.ppat.1005052] [Citation(s) in RCA: 87] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Kaposi’s Sarcoma-associated Herpesvirus (KSHV) is the etiologic agent of Kaposi’s Sarcoma (KS). KSHV establishes a predominantly latent infection in the main KS tumor cell type, the spindle cell, which is of endothelial cell origin. KSHV requires the induction of multiple metabolic pathways, including glycolysis and fatty acid synthesis, for the survival of latently infected endothelial cells. Here we demonstrate that latent KSHV infection leads to increased levels of intracellular glutamine and enhanced glutamine uptake. Depletion of glutamine from the culture media leads to a significant increase in apoptotic cell death in latently infected endothelial cells, but not in their mock-infected counterparts. In cancer cells, glutamine is often required for glutaminolysis to provide intermediates for the tri-carboxylic acid (TCA) cycle and support for the production of biosynthetic and bioenergetic precursors. In the absence of glutamine, the TCA cycle intermediates alpha-ketoglutarate (αKG) and pyruvate prevent the death of latently infected cells. Targeted drug inhibition of glutaminolysis also induces increased cell death in latently infected cells. KSHV infection of endothelial cells induces protein expression of the glutamine transporter, SLC1A5. Chemical inhibition of SLC1A5, or knockdown by siRNA, leads to similar cell death rates as glutamine deprivation and, similarly, can be rescued by αKG. KSHV also induces expression of the heterodimeric transcription factors c-Myc-Max and related heterodimer MondoA-Mlx. Knockdown of MondoA inhibits expression of both Mlx and SLC1A5 and induces a significant increase in cell death of only cells latently infected with KSHV, again, fully rescued by the supplementation of αKG. Therefore, during latent infection of endothelial cells, KSHV activates and requires the Myc/MondoA-network to upregulate the glutamine transporter, SLC1A5, leading to increased glutamine uptake for glutaminolysis. These findings expand our understanding of the required metabolic pathways that are activated during latent KSHV infection of endothelial cells, and demonstrate a novel role for the extended Myc-regulatory network, specifically MondoA, during latent KSHV infection. KSHV is the etiologic agent of KS, the most common tumor of AIDS patients worldwide. Currently, there are no therapeutics available to directly treat latent KSHV infection. This study reveals that latent KSHV infection induces endothelial cells to become glutamine addicted, similarly to cancer cells. Extracellular glutamine is required to feed the TCA cycle through glutaminolysis, a process called anaplerosis. KSHV induces protein expression of the glutamine transporter SLC1A5 and SLC1A5 expression is required for the survival of latently infected cells. KSHV also induces the expression of the proto-oncogene Myc and its binding partner Max, as well as, the nutrient-sensing transcription factor, MondoA and its binding partner Mlx. MondoA regulates SLC1A5 and glutaminolysis during latent KSHV infection, and its expression is required for the survival of latently infected endothelial cells. These studies show that glutaminolysis and a single glutamine transporter, under the regulation of MondoA, are required for the survival of latently infected cells, providing novel druggable targets for latently infected endothelial cells. This work supports that a cancer-like metabolic signature is established by latent KSHV infection, opening the door to further therapeutic targeting specifically of KSHV latently infected cells.
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Affiliation(s)
- Erica L. Sanchez
- Molecular and Cellular Biology Program, University of Washington, Seattle, Washington, United States of America
- Department of Microbiology, University of Washington, Seattle, Washington, United States of America
| | - Patrick A. Carroll
- Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
| | - Angel B. Thalhofer
- Department of Microbiology, University of Washington, Seattle, Washington, United States of America
| | - Michael Lagunoff
- Molecular and Cellular Biology Program, University of Washington, Seattle, Washington, United States of America
- Department of Microbiology, University of Washington, Seattle, Washington, United States of America
- * E-mail:
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117
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Tameire F, Verginadis II, Koumenis C. Cell intrinsic and extrinsic activators of the unfolded protein response in cancer: Mechanisms and targets for therapy. Semin Cancer Biol 2015; 33:3-15. [PMID: 25920797 DOI: 10.1016/j.semcancer.2015.04.002] [Citation(s) in RCA: 79] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Accepted: 04/16/2015] [Indexed: 02/07/2023]
Abstract
A variety of cell intrinsic or extrinsic stresses evoke perturbations in the folding environment of the endoplasmic reticulum (ER), collectively known as ER stress. Adaptation to stress and re-establishment of ER homeostasis is achieved by activation of an integrated signal transduction pathway called the unfolded protein response (UPR). Both ER stress and UPR activation have been implicated in a variety of human cancers. Although at early stages or physiological conditions of ER stress, the UPR generally promotes survival, when the stress becomes more stringent or prolonged, its role can switch to a pro-cell death one. Here, we discuss historical and recent evidence supporting an involvement of the UPR in malignancy, describe the main mechanisms by which tumor cells overcome ER stress to promote their survival, tumor progression and metastasis and discuss the current state of efforts to develop therapeutic approaches of targeting the UPR.
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Affiliation(s)
- Feven Tameire
- Department of Radiation Oncology, Perelman University School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; Program in Cell and Molecular Biology, Perelman University School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Ioannis I Verginadis
- Department of Radiation Oncology, Perelman University School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Constantinos Koumenis
- Department of Radiation Oncology, Perelman University School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
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118
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Wang Q, Hardie RA, Hoy AJ, van Geldermalsen M, Gao D, Fazli L, Sadowski MC, Balaban S, Schreuder M, Nagarajah R, Wong JJL, Metierre C, Pinello N, Otte NJ, Lehman ML, Gleave M, Nelson CC, Bailey CG, Ritchie W, Rasko JEJ, Holst J. Targeting ASCT2-mediated glutamine uptake blocks prostate cancer growth and tumour development. J Pathol 2015; 236:278-89. [PMID: 25693838 PMCID: PMC4973854 DOI: 10.1002/path.4518] [Citation(s) in RCA: 260] [Impact Index Per Article: 28.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2014] [Revised: 01/19/2015] [Accepted: 02/12/2015] [Indexed: 12/11/2022]
Abstract
Glutamine is conditionally essential in cancer cells, being utilized as a carbon and nitrogen source for macromolecule production, as well as for anaplerotic reactions fuelling the tricarboxylic acid (TCA) cycle. In this study, we demonstrated that the glutamine transporter ASCT2 (SLC1A5) is highly expressed in prostate cancer patient samples. Using LNCaP and PC‐3 prostate cancer cell lines, we showed that chemical or shRNA‐mediated inhibition of ASCT2 function in vitro decreases glutamine uptake, cell cycle progression through E2F transcription factors, mTORC1 pathway activation and cell growth. Chemical inhibition also reduces basal oxygen consumption and fatty acid synthesis, showing that downstream metabolic function is reliant on ASCT2‐mediated glutamine uptake. Furthermore, shRNA knockdown of ASCT2 in PC‐3 cell xenografts significantly inhibits tumour growth and metastasis in vivo, associated with the down‐regulation of E2F cell cycle pathway proteins. In conclusion, ASCT2‐mediated glutamine uptake is essential for multiple pathways regulating the cell cycle and cell growth, and is therefore a putative therapeutic target in prostate cancer. © 2015 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.
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Affiliation(s)
- Qian Wang
- Origins of Cancer Laboratory, Centenary Institute, Camperdown, NSW, Australia.,Sydney Medical School, University of Sydney, NSW, Australia.,Gene and Stem Cell Therapy Program, Centenary Institute, Camperdown, NSW, Australia
| | - Rae-Anne Hardie
- Origins of Cancer Laboratory, Centenary Institute, Camperdown, NSW, Australia.,Sydney Medical School, University of Sydney, NSW, Australia.,Gene and Stem Cell Therapy Program, Centenary Institute, Camperdown, NSW, Australia
| | - Andrew J Hoy
- Discipline of Physiology, Bosch Institute and Charles Perkins Centre, University of Sydney, NSW, Australia
| | - Michelle van Geldermalsen
- Origins of Cancer Laboratory, Centenary Institute, Camperdown, NSW, Australia.,Sydney Medical School, University of Sydney, NSW, Australia.,Gene and Stem Cell Therapy Program, Centenary Institute, Camperdown, NSW, Australia
| | - Dadi Gao
- Sydney Medical School, University of Sydney, NSW, Australia.,Gene and Stem Cell Therapy Program, Centenary Institute, Camperdown, NSW, Australia.,Bioinformatics, Centenary Institute, Camperdown, NSW, Australia
| | - Ladan Fazli
- Department of Urologic Sciences, University of British Columbia, Vancouver, BC, Canada
| | - Martin C Sadowski
- Australian Prostate Cancer Research Centre-Queensland, Queensland University of Technology, Australia
| | - Seher Balaban
- Discipline of Physiology, Bosch Institute and Charles Perkins Centre, University of Sydney, NSW, Australia
| | - Mark Schreuder
- Discipline of Physiology, Bosch Institute and Charles Perkins Centre, University of Sydney, NSW, Australia
| | - Rajini Nagarajah
- Origins of Cancer Laboratory, Centenary Institute, Camperdown, NSW, Australia.,Sydney Medical School, University of Sydney, NSW, Australia.,Gene and Stem Cell Therapy Program, Centenary Institute, Camperdown, NSW, Australia
| | - Justin J-L Wong
- Sydney Medical School, University of Sydney, NSW, Australia.,Gene and Stem Cell Therapy Program, Centenary Institute, Camperdown, NSW, Australia
| | - Cynthia Metierre
- Sydney Medical School, University of Sydney, NSW, Australia.,Gene and Stem Cell Therapy Program, Centenary Institute, Camperdown, NSW, Australia
| | - Natalia Pinello
- Sydney Medical School, University of Sydney, NSW, Australia.,Gene and Stem Cell Therapy Program, Centenary Institute, Camperdown, NSW, Australia
| | - Nicholas J Otte
- Origins of Cancer Laboratory, Centenary Institute, Camperdown, NSW, Australia.,Sydney Medical School, University of Sydney, NSW, Australia.,Gene and Stem Cell Therapy Program, Centenary Institute, Camperdown, NSW, Australia
| | - Melanie L Lehman
- Australian Prostate Cancer Research Centre-Queensland, Queensland University of Technology, Australia
| | - Martin Gleave
- Department of Urologic Sciences, University of British Columbia, Vancouver, BC, Canada
| | - Colleen C Nelson
- Australian Prostate Cancer Research Centre-Queensland, Queensland University of Technology, Australia
| | - Charles G Bailey
- Sydney Medical School, University of Sydney, NSW, Australia.,Gene and Stem Cell Therapy Program, Centenary Institute, Camperdown, NSW, Australia
| | - William Ritchie
- Sydney Medical School, University of Sydney, NSW, Australia.,Gene and Stem Cell Therapy Program, Centenary Institute, Camperdown, NSW, Australia.,Bioinformatics, Centenary Institute, Camperdown, NSW, Australia
| | - John E J Rasko
- Sydney Medical School, University of Sydney, NSW, Australia.,Gene and Stem Cell Therapy Program, Centenary Institute, Camperdown, NSW, Australia.,Cell and Molecular Therapies, Royal Prince Alfred Hospital, Camperdown, NSW, Australia
| | - Jeff Holst
- Origins of Cancer Laboratory, Centenary Institute, Camperdown, NSW, Australia.,Sydney Medical School, University of Sydney, NSW, Australia.,Gene and Stem Cell Therapy Program, Centenary Institute, Camperdown, NSW, Australia
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119
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Wang Q, Hardie RA, Hoy AJ, van Geldermalsen M, Gao D, Fazli L, Sadowski MC, Balaban S, Schreuder M, Nagarajah R, Wong JJL, Metierre C, Pinello N, Otte NJ, Lehman ML, Gleave M, Nelson CC, Bailey CG, Ritchie W, Rasko JEJ, Holst J. Targeting ASCT2-mediated glutamine uptake blocks prostate cancer growth and tumour development. J Pathol 2015. [PMID: 25693838 DOI: 10.1002/path.4518.] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Glutamine is conditionally essential in cancer cells, being utilized as a carbon and nitrogen source for macromolecule production, as well as for anaplerotic reactions fuelling the tricarboxylic acid (TCA) cycle. In this study, we demonstrated that the glutamine transporter ASCT2 (SLC1A5) is highly expressed in prostate cancer patient samples. Using LNCaP and PC-3 prostate cancer cell lines, we showed that chemical or shRNA-mediated inhibition of ASCT2 function in vitro decreases glutamine uptake, cell cycle progression through E2F transcription factors, mTORC1 pathway activation and cell growth. Chemical inhibition also reduces basal oxygen consumption and fatty acid synthesis, showing that downstream metabolic function is reliant on ASCT2-mediated glutamine uptake. Furthermore, shRNA knockdown of ASCT2 in PC-3 cell xenografts significantly inhibits tumour growth and metastasis in vivo, associated with the down-regulation of E2F cell cycle pathway proteins. In conclusion, ASCT2-mediated glutamine uptake is essential for multiple pathways regulating the cell cycle and cell growth, and is therefore a putative therapeutic target in prostate cancer.
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Affiliation(s)
- Qian Wang
- Origins of Cancer Laboratory, Centenary Institute, Camperdown, NSW, Australia.,Sydney Medical School, University of Sydney, NSW, Australia.,Gene and Stem Cell Therapy Program, Centenary Institute, Camperdown, NSW, Australia
| | - Rae-Anne Hardie
- Origins of Cancer Laboratory, Centenary Institute, Camperdown, NSW, Australia.,Sydney Medical School, University of Sydney, NSW, Australia.,Gene and Stem Cell Therapy Program, Centenary Institute, Camperdown, NSW, Australia
| | - Andrew J Hoy
- Discipline of Physiology, Bosch Institute and Charles Perkins Centre, University of Sydney, NSW, Australia
| | - Michelle van Geldermalsen
- Origins of Cancer Laboratory, Centenary Institute, Camperdown, NSW, Australia.,Sydney Medical School, University of Sydney, NSW, Australia.,Gene and Stem Cell Therapy Program, Centenary Institute, Camperdown, NSW, Australia
| | - Dadi Gao
- Sydney Medical School, University of Sydney, NSW, Australia.,Gene and Stem Cell Therapy Program, Centenary Institute, Camperdown, NSW, Australia.,Bioinformatics, Centenary Institute, Camperdown, NSW, Australia
| | - Ladan Fazli
- Department of Urologic Sciences, University of British Columbia, Vancouver, BC, Canada
| | - Martin C Sadowski
- Australian Prostate Cancer Research Centre-Queensland, Queensland University of Technology, Australia
| | - Seher Balaban
- Discipline of Physiology, Bosch Institute and Charles Perkins Centre, University of Sydney, NSW, Australia
| | - Mark Schreuder
- Discipline of Physiology, Bosch Institute and Charles Perkins Centre, University of Sydney, NSW, Australia
| | - Rajini Nagarajah
- Origins of Cancer Laboratory, Centenary Institute, Camperdown, NSW, Australia.,Sydney Medical School, University of Sydney, NSW, Australia.,Gene and Stem Cell Therapy Program, Centenary Institute, Camperdown, NSW, Australia
| | - Justin J-L Wong
- Sydney Medical School, University of Sydney, NSW, Australia.,Gene and Stem Cell Therapy Program, Centenary Institute, Camperdown, NSW, Australia
| | - Cynthia Metierre
- Sydney Medical School, University of Sydney, NSW, Australia.,Gene and Stem Cell Therapy Program, Centenary Institute, Camperdown, NSW, Australia
| | - Natalia Pinello
- Sydney Medical School, University of Sydney, NSW, Australia.,Gene and Stem Cell Therapy Program, Centenary Institute, Camperdown, NSW, Australia
| | - Nicholas J Otte
- Origins of Cancer Laboratory, Centenary Institute, Camperdown, NSW, Australia.,Sydney Medical School, University of Sydney, NSW, Australia.,Gene and Stem Cell Therapy Program, Centenary Institute, Camperdown, NSW, Australia
| | - Melanie L Lehman
- Australian Prostate Cancer Research Centre-Queensland, Queensland University of Technology, Australia
| | - Martin Gleave
- Department of Urologic Sciences, University of British Columbia, Vancouver, BC, Canada
| | - Colleen C Nelson
- Australian Prostate Cancer Research Centre-Queensland, Queensland University of Technology, Australia
| | - Charles G Bailey
- Sydney Medical School, University of Sydney, NSW, Australia.,Gene and Stem Cell Therapy Program, Centenary Institute, Camperdown, NSW, Australia
| | - William Ritchie
- Sydney Medical School, University of Sydney, NSW, Australia.,Gene and Stem Cell Therapy Program, Centenary Institute, Camperdown, NSW, Australia.,Bioinformatics, Centenary Institute, Camperdown, NSW, Australia
| | - John E J Rasko
- Sydney Medical School, University of Sydney, NSW, Australia.,Gene and Stem Cell Therapy Program, Centenary Institute, Camperdown, NSW, Australia.,Cell and Molecular Therapies, Royal Prince Alfred Hospital, Camperdown, NSW, Australia
| | - Jeff Holst
- Origins of Cancer Laboratory, Centenary Institute, Camperdown, NSW, Australia.,Sydney Medical School, University of Sydney, NSW, Australia.,Gene and Stem Cell Therapy Program, Centenary Institute, Camperdown, NSW, Australia
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Ye Q, Yao G, Zhang M, Guo G, Hu Y, Jiang J, Cheng L, Shi J, Li H, Zhang Y, Liu H. A novel ent-kaurane diterpenoid executes antitumor function in colorectal cancer cells by inhibiting Wnt/β-catenin signaling. Carcinogenesis 2015; 36:318-26. [PMID: 25600769 DOI: 10.1093/carcin/bgv003] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Aberrant activation of Wnt signaling pathway is crucial for the onset and progression of human colorectal cancer (CRC). Owing to the persistent dependence on Wnt signaling for growth and survival, inhibition of this pathway is an attractive approach for new therapies. 11α, 12α-epoxyleukamenin E (EPLE) is a novel ent-kaurane diterpenoid that we previously isolated from Salvia cavaleriei, exhibiting antitumor activities in a variety of cancer cells. Herein, we found that whereas sparing normal human colon mucosal epithelial cells, EPLE selectively inhibited the proliferation of CRC cell lines as well as primary tumor cells. Mechanistically, we demonstrated EPLE exerted its function through suppressing Wnt signaling pathway, as evidenced by EPLE-mediated downregulation of Wnt target genes such as c-Myc, Axin2 and Survivin. Consistently, luciferase reporter assays showed that the EPLE directly blocked Wnt/β-catenin-mediated transcriptional activation. In combination of co-immunoprecipitation and protein structure-based analyses, we determined that the EPLE entered the interface of β-catenin/TCF4 complexes and blocked their interaction that is required for β-catenin-mediated transcriptional activation. Moreover, overexpression of β-catenin alleviated the cytotoxicity of EPLE in CRC cells, supporting Wnt signaling is a major and specific target of EPLE. Combined treatments of EPLE and 5-fluorouracil, the first-line chemotherapy for CRC patients, achieved a synergistic effect. More importantly, EPLE hampered tumor development in a CRC xenograft model. Our data thus establish EPLE as a novel inhibitor of Wnt signaling that holds great promise as a potential candidate for further preclinical evaluation for CRC treatments.
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Affiliation(s)
- Qi Ye
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy andDepartment of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P. R. China
| | - Guangmin Yao
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy andDepartment of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P. R. China
| | - Mengke Zhang
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy andDepartment of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P. R. China
| | - Guoli Guo
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy andDepartment of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P. R. China
| | - Yufeng Hu
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy andDepartment of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P. R. China
| | - Jue Jiang
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy andDepartment of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P. R. China
| | - Ling Cheng
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy andDepartment of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P. R. China
| | - Jianguo Shi
- Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P. R. China
| | - Hua Li
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy andDepartment of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P. R. China
| | - Yonghui Zhang
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy andDepartment of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P. R. China
| | - Hudan Liu
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy andDepartment of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P. R. China
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Aminzadeh S, Vidali S, Sperl W, Kofler B, Feichtinger RG. Energy metabolism in neuroblastoma and Wilms tumor. Transl Pediatr 2015; 4:20-32. [PMID: 26835356 PMCID: PMC4729069 DOI: 10.3978/j.issn.2224-4336.2015.01.04] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
To support high proliferation, the majority of cancer cells undergo fundamental metabolic changes such as increasing their glucose uptake and shifting to glycolysis for ATP production at the expense of far more efficient mitochondrial energy production by oxidative phosphorylation (OXPHOS), which at first glance is a paradox. This phenomenon is known as the Warburg effect. However, enhanced glycolysis is necessary to provide building blocks for anabolic growth. Apart from the generation of ATP, intermediates of glycolysis serve as precursors for a variety of biosynthetic pathways essential for cell proliferation. In the last 10-15 years the field of tumor metabolism has experienced an enormous boom in interest. It is now well established that tumor suppressor genes and oncogenes often play a central role in the regulation of cellular metabolism. Therefore, they significantly contribute to the manifestation of the Warburg effect. While much attention has focused on adult solid tumors, so far there has been comparatively little effort directed at elucidation of the mechanism responsible for the Warburg effect in childhood cancers. In this review we focus on metabolic pathways in neuroblastoma (NB) and Wilms tumor (WT), the two most frequent solid tumors in children. Both tumor types show alterations of the OXPHOS system and glycolytic features. Chromosomal alterations and activation of oncogenes like MYC or inactivation of tumor suppressor genes like TP53 can in part explain the changes of energy metabolism in these cancers. The strict dependence of cancer cells on glucose metabolism is a fairly common feature among otherwise biologically diverse types of cancer. Therefore, inhibition of glycolysis or starvation of cancer cells through glucose deprivation via a high-fat low-carbohydrate diet may be a promising avenue for future adjuvant therapeutic strategies.
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