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Keller M, Rohlf K, Glotzbach A, Leonhardt G, Lüke S, Derksen K, Demirci Ö, Göçener D, AlWahsh M, Lambert J, Lindskog C, Schmidt M, Brenner W, Baumann M, Zent E, Zischinsky ML, Hellwig B, Madjar K, Rahnenführer J, Overbeck N, Reinders J, Cadenas C, Hengstler JG, Edlund K, Marchan R. Inhibiting the glycerophosphodiesterase EDI3 in ER-HER2+ breast cancer cells resistant to HER2-targeted therapy reduces viability and tumour growth. JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH : CR 2023; 42:25. [PMID: 36670508 PMCID: PMC9854078 DOI: 10.1186/s13046-022-02578-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Accepted: 12/20/2022] [Indexed: 01/22/2023]
Abstract
BACKGROUND Intrinsic or acquired resistance to HER2-targeted therapy is often a problem when small molecule tyrosine kinase inhibitors or antibodies are used to treat patients with HER2 positive breast cancer. Therefore, the identification of new targets and therapies for this patient group is warranted. Activated choline metabolism, characterized by elevated levels of choline-containing compounds, has been previously reported in breast cancer. The glycerophosphodiesterase EDI3 (GPCPD1), which hydrolyses glycerophosphocholine to choline and glycerol-3-phosphate, directly influences choline and phospholipid metabolism, and has been linked to cancer-relevant phenotypes in vitro. While the importance of choline metabolism has been addressed in breast cancer, the role of EDI3 in this cancer type has not been explored. METHODS EDI3 mRNA and protein expression in human breast cancer tissue were investigated using publicly-available Affymetrix gene expression microarray datasets (n = 540) and with immunohistochemistry on a tissue microarray (n = 265), respectively. A panel of breast cancer cell lines of different molecular subtypes were used to investigate expression and activity of EDI3 in vitro. To determine whether EDI3 expression is regulated by HER2 signalling, the effect of pharmacological inhibition and siRNA silencing of HER2, as well as the influence of inhibiting key components of signalling cascades downstream of HER2 were studied. Finally, the influence of silencing and pharmacologically inhibiting EDI3 on viability was investigated in vitro and on tumour growth in vivo. RESULTS In the present study, we show that EDI3 expression is highest in ER-HER2 + human breast tumours, and both expression and activity were also highest in ER-HER2 + breast cancer cell lines. Silencing HER2 using siRNA, as well as inhibiting HER2 signalling with lapatinib decreased EDI3 expression. Pathways downstream of PI3K/Akt/mTOR and GSK3β, and transcription factors, including HIF1α, CREB and STAT3 were identified as relevant in regulating EDI3 expression. Silencing EDI3 preferentially decreased cell viability in the ER-HER2 + cells. Furthermore, silencing or pharmacologically inhibiting EDI3 using dipyridamole in ER-HER2 + cells resistant to HER2-targeted therapy decreased cell viability in vitro and tumour growth in vivo. CONCLUSIONS Our results indicate that EDI3 may be a potential novel therapeutic target in patients with HER2-targeted therapy-resistant ER-HER2 + breast cancer that should be further explored.
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Affiliation(s)
- Magdalena Keller
- grid.419241.b0000 0001 2285 956XLeibniz Research Centre for Working Environment and Human Factors at the TU Dortmund (IfADo), Ardeystrasse 67, 44139 Dortmund, Germany
| | - Katharina Rohlf
- grid.419241.b0000 0001 2285 956XLeibniz Research Centre for Working Environment and Human Factors at the TU Dortmund (IfADo), Ardeystrasse 67, 44139 Dortmund, Germany
| | - Annika Glotzbach
- grid.419241.b0000 0001 2285 956XLeibniz Research Centre for Working Environment and Human Factors at the TU Dortmund (IfADo), Ardeystrasse 67, 44139 Dortmund, Germany
| | - Gregor Leonhardt
- grid.419241.b0000 0001 2285 956XLeibniz Research Centre for Working Environment and Human Factors at the TU Dortmund (IfADo), Ardeystrasse 67, 44139 Dortmund, Germany
| | - Simon Lüke
- grid.419241.b0000 0001 2285 956XLeibniz Research Centre for Working Environment and Human Factors at the TU Dortmund (IfADo), Ardeystrasse 67, 44139 Dortmund, Germany
| | - Katharina Derksen
- grid.419241.b0000 0001 2285 956XLeibniz Research Centre for Working Environment and Human Factors at the TU Dortmund (IfADo), Ardeystrasse 67, 44139 Dortmund, Germany
| | - Özlem Demirci
- grid.419241.b0000 0001 2285 956XLeibniz Research Centre for Working Environment and Human Factors at the TU Dortmund (IfADo), Ardeystrasse 67, 44139 Dortmund, Germany
| | - Defne Göçener
- grid.419241.b0000 0001 2285 956XLeibniz Research Centre for Working Environment and Human Factors at the TU Dortmund (IfADo), Ardeystrasse 67, 44139 Dortmund, Germany
| | - Mohammad AlWahsh
- grid.419243.90000 0004 0492 9407Leibniz Institut Für Analytische Wissenschaften - ISAS E.V, Dortmund, Germany ,grid.411778.c0000 0001 2162 1728Institute of Pathology and Medical Research Center (ZMF), University Medical Center Mannheim, Heidelberg University, Mannheim, Germany ,grid.443348.c0000 0001 0244 5415Department of Pharmacy, AlZaytoonah University of Jordan, Amman, Jordan
| | - Jörg Lambert
- grid.419243.90000 0004 0492 9407Leibniz Institut Für Analytische Wissenschaften - ISAS E.V, Dortmund, Germany
| | - Cecilia Lindskog
- grid.8993.b0000 0004 1936 9457Department of Immunology Genetics and Pathology, Uppsala University, Uppsala, Sweden
| | - Marcus Schmidt
- grid.410607.4Department of Obstetrics and Gynecology, University Medical Center Mainz, Mainz, Germany
| | - Walburgis Brenner
- grid.410607.4Department of Obstetrics and Gynecology, University Medical Center Mainz, Mainz, Germany
| | - Matthias Baumann
- grid.505582.fPharmacology Department, Lead Discovery Center, Dortmund, Germany
| | - Eldar Zent
- grid.505582.fPharmacology Department, Lead Discovery Center, Dortmund, Germany
| | - Mia-Lisa Zischinsky
- grid.505582.fPharmacology Department, Lead Discovery Center, Dortmund, Germany
| | - Birte Hellwig
- grid.5675.10000 0001 0416 9637Department of Statistics, TU Dortmund University, Dortmund, Germany
| | - Katrin Madjar
- grid.5675.10000 0001 0416 9637Department of Statistics, TU Dortmund University, Dortmund, Germany
| | - Jörg Rahnenführer
- grid.5675.10000 0001 0416 9637Department of Statistics, TU Dortmund University, Dortmund, Germany
| | - Nina Overbeck
- grid.419241.b0000 0001 2285 956XLeibniz Research Centre for Working Environment and Human Factors at the TU Dortmund (IfADo), Ardeystrasse 67, 44139 Dortmund, Germany
| | - Jörg Reinders
- grid.419241.b0000 0001 2285 956XLeibniz Research Centre for Working Environment and Human Factors at the TU Dortmund (IfADo), Ardeystrasse 67, 44139 Dortmund, Germany
| | - Cristina Cadenas
- grid.419241.b0000 0001 2285 956XLeibniz Research Centre for Working Environment and Human Factors at the TU Dortmund (IfADo), Ardeystrasse 67, 44139 Dortmund, Germany
| | - Jan G. Hengstler
- grid.419241.b0000 0001 2285 956XLeibniz Research Centre for Working Environment and Human Factors at the TU Dortmund (IfADo), Ardeystrasse 67, 44139 Dortmund, Germany
| | - Karolina Edlund
- grid.419241.b0000 0001 2285 956XLeibniz Research Centre for Working Environment and Human Factors at the TU Dortmund (IfADo), Ardeystrasse 67, 44139 Dortmund, Germany
| | - Rosemarie Marchan
- grid.419241.b0000 0001 2285 956XLeibniz Research Centre for Working Environment and Human Factors at the TU Dortmund (IfADo), Ardeystrasse 67, 44139 Dortmund, Germany
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Wu Y, Zhang Y, Jiao J. The relationship between n-3 polyunsaturated fatty acids and telomere: A review on proposed nutritional treatment against metabolic syndrome and potential signaling pathways. Crit Rev Food Sci Nutr 2022; 64:4457-4476. [PMID: 36330807 DOI: 10.1080/10408398.2022.2142196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Metabolic syndrome (MetS), a cluster of metabolic abnormalities composed of central obesity, elevated blood pressure, glucose disturbances, hypercholesterolemia and dyslipidaemia, has increasingly become a public health problem in the 21st century worldwide. The dysfunction of telomeres, the repetitive DNA with highly conserved sequences (5'-TTAGGG-3'), is remarkably correlated with organismal aging, even suggesting a causal relationship with metabolic disorders. The health benefits of n-3 polyunsaturated fatty acids (PUFAs) in multiple disorders are associated with telomere length in evidence, which have recently drawn wide attention. However, functional targets and pathways for the associations of n-3 PUFAs and telomere with MetS remain scare. Few studies have summarized the role of n-3 PUFAs in DNA damage repair pathways, anti-inflammatory pathways, and redox balance, linking with telomere biology, and other potential telomere-related signaling pathways. This review aims to (i) elucidate how n-3 PUFAs ameliorate telomere attrition in the context of anti-oxidation and anti-inflammation; (ii) unravel the role of n-3 PUFAs in modulating telomere-related neuron dysfunction and regulating the neuro-endocrine-immunological network in MetS; (iii) epidemiologically implicate the associations of metabolic disorders and n-3 PUFAs with telomere length; and (iv) suggest promising biochemical approaches and advancing methodologies to overcome the inter-variation problem helpful for future research.
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Affiliation(s)
- Yuqi Wu
- National Engineering Laboratory of Intelligent Food Technology and Equipment, Zhejiang Key Laboratory for Agro-Food Processing, Fuli Institute of Food Science, College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, Zhejiang, China
| | - Yu Zhang
- National Engineering Laboratory of Intelligent Food Technology and Equipment, Zhejiang Key Laboratory for Agro-Food Processing, Fuli Institute of Food Science, College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, Zhejiang, China
| | - Jingjing Jiao
- Department of Nutrition, School of Public Health, Department of Clinical Nutrition, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
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Glycogen Synthase Kinase 3β in Cancer Biology and Treatment. Cells 2020; 9:cells9061388. [PMID: 32503133 PMCID: PMC7349761 DOI: 10.3390/cells9061388] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 05/28/2020] [Accepted: 06/01/2020] [Indexed: 12/15/2022] Open
Abstract
Glycogen synthase kinase (GSK)3β is a multifunctional serine/threonine protein kinase with more than 100 substrates and interacting molecules. GSK3β is normally active in cells and negative regulation of GSK3β activity via phosphorylation of its serine 9 residue is required for most normal cells to maintain homeostasis. Aberrant expression and activity of GSK3β contributes to the pathogenesis and progression of common recalcitrant diseases such as glucose intolerance, neurodegenerative disorders and cancer. Despite recognized roles against several proto-oncoproteins and mediators of the epithelial–mesenchymal transition, deregulated GSK3β also participates in tumor cell survival, evasion of apoptosis, proliferation and invasion, as well as sustaining cancer stemness and inducing therapy resistance. A therapeutic effect from GSK3β inhibition has been demonstrated in 25 different cancer types. Moreover, there is increasing evidence that GSK3β inhibition protects normal cells and tissues from the harmful effects associated with conventional cancer therapies. Here, we review the evidence supporting aberrant GSK3β as a hallmark property of cancer and highlight the beneficial effects of GSK3β inhibition on normal cells and tissues during cancer therapy. The biological rationale for targeting GSK3β in the treatment of cancer is also discussed at length.
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Time-Dependent Effects of POT1 Knockdown on Proliferation, Tumorigenicity, and HDACi Response of SK-OV3 Ovarian Cancer Cells. BIOMED RESEARCH INTERNATIONAL 2018; 2018:7184253. [PMID: 29546066 PMCID: PMC5818924 DOI: 10.1155/2018/7184253] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/17/2017] [Accepted: 12/21/2017] [Indexed: 02/07/2023]
Abstract
The roles of protection of telomeres 1 (POT1) in human ovarian cancer have not been fully elucidated. Here, we investigated the impact of POT1 knockdown (POT1-KD) on in vitro cell proliferation, tumorigenesis, and histone deacetylase inhibitor (HDACi) response in human ovarian cancer-derived SK-OV3 cells. The POT1 gene was knocked down by infection with POT1 lenti-shRNA. POT1, c-Myc, and hTERT mRNA levels and relative telomere length were determined by qRT-PCR; POT1 protein levels were determined by western blot. The relative telomerase activity levels were detected using qTRAP; cell proliferation was assessed using cumulative population doubling (cPD) experiments. Cell tumorigenicity was evaluated by anchorage-independent cell growth assays, and cell response to HDACi was determined by luminescence cell viability assays. Results indicate that lenti-shRNA-mediated POT1-KD significantly reduced POT1 mRNA and protein expression. POT1-KD immediately downregulated c-Myc expression, which led to the inhibition of cell proliferation, tumorigenesis, and HDACi response. However, after brief suppression, c-Myc expression increased in the medium term, which resulted in enhanced cell proliferation, tumorigenesis, and HDACi response in the POT1-KD cells. Furthermore, we discovered that c-Myc regulated cell proliferation and tumorigenesis via hTERT/telomerase/telomere pathway.
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Cairney CJ, Godwin LS, Bilsland AE, Burns S, Stevenson KH, McGarry L, Revie J, Moore JD, Wiggins CM, Collinson RS, Mudd C, Tsonou E, Sadaie M, Bennett DC, Narita M, Torrance CJ, Keith WN. A 'synthetic-sickness' screen for senescence re-engagement targets in mutant cancer backgrounds. PLoS Genet 2017; 13:e1006942. [PMID: 28806777 PMCID: PMC5570495 DOI: 10.1371/journal.pgen.1006942] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Revised: 08/24/2017] [Accepted: 07/25/2017] [Indexed: 12/24/2022] Open
Abstract
Senescence is a universal barrier to immortalisation and tumorigenesis. As such, interest in the use of senescence-induction in a therapeutic context has been gaining momentum in the past few years; however, senescence and immortalisation remain underserved areas for drug discovery owing to a lack of robust senescence inducing agents and an incomplete understanding of the signalling events underlying this complex process. In order to address this issue we undertook a large-scale morphological siRNA screen for inducers of senescence phenotypes in the human melanoma cell line A375P. Following rescreen and validation in a second cancer cell line, HCT116 colorectal carcinoma, a panel of 16 of the most robust hits were selected for further validation based on significance and the potential to be targeted by drug-like molecules. Using secondary assays for detection of senescence biomarkers p21, 53BP1 and senescence associated beta-galactosidase (SAβGal) in a panel of HCT116 cell lines carrying cancer-relevant mutations, we show that partial senescence phenotypes can be induced to varying degrees in a context dependent manner, even in the absence of p21 or p53 expression. However, proliferation arrest varied among genetic backgrounds with predominantly toxic effects in p21 null cells, while cells lacking PI3K mutation failed to arrest. Furthermore, we show that the oncogene ECT2 induces partial senescence phenotypes in all mutant backgrounds tested, demonstrating a dependence on activating KRASG13D for growth suppression and a complete senescence response. These results suggest a potential mechanism to target mutant KRAS signalling through ECT2 in cancers that are reliant on activating KRAS mutations and remain refractory to current treatments.
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Affiliation(s)
- Claire J. Cairney
- Institute of Cancer Sciences, Wolfson Wohl Cancer Research Centre, University of Glasgow, Glasgow, United Kingdom
| | - Lauren S. Godwin
- Molecular and Clinical Sciences Research Institute, St. George's, University of London, London, United Kingdom
| | - Alan E. Bilsland
- Institute of Cancer Sciences, Wolfson Wohl Cancer Research Centre, University of Glasgow, Glasgow, United Kingdom
| | - Sharon Burns
- Institute of Cancer Sciences, Wolfson Wohl Cancer Research Centre, University of Glasgow, Glasgow, United Kingdom
| | - Katrina H. Stevenson
- Institute of Cancer Sciences, Wolfson Wohl Cancer Research Centre, University of Glasgow, Glasgow, United Kingdom
| | - Lynn McGarry
- RNAi Screening Facility, Cancer Research UK Beatson Institute, Glasgow, United Kingdom
| | - John Revie
- Institute of Cancer Sciences, Wolfson Wohl Cancer Research Centre, University of Glasgow, Glasgow, United Kingdom
| | - Jon D. Moore
- Horizon Discovery Ltd, Cambridge Research Park, Waterbeach, Cambridge, United Kingdom
| | - Ceri M. Wiggins
- Horizon Discovery Ltd, Cambridge Research Park, Waterbeach, Cambridge, United Kingdom
| | - Rebecca S. Collinson
- Molecular and Clinical Sciences Research Institute, St. George's, University of London, London, United Kingdom
| | - Clare Mudd
- Horizon Discovery Ltd, Cambridge Research Park, Waterbeach, Cambridge, United Kingdom
| | - Elpida Tsonou
- Horizon Discovery Ltd, Cambridge Research Park, Waterbeach, Cambridge, United Kingdom
| | - Mahito Sadaie
- Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge, United Kingdom
| | - Dorothy C. Bennett
- Molecular and Clinical Sciences Research Institute, St. George's, University of London, London, United Kingdom
| | - Masashi Narita
- Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge, United Kingdom
| | | | - W. Nicol Keith
- Institute of Cancer Sciences, Wolfson Wohl Cancer Research Centre, University of Glasgow, Glasgow, United Kingdom
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6
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Transcription Regulation of the Human Telomerase Reverse Transcriptase (hTERT) Gene. Genes (Basel) 2016; 7:genes7080050. [PMID: 27548225 PMCID: PMC4999838 DOI: 10.3390/genes7080050] [Citation(s) in RCA: 101] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Revised: 07/23/2016] [Accepted: 08/01/2016] [Indexed: 12/11/2022] Open
Abstract
Embryonic stem cells and induced pluripotent stem cells have the ability to maintain their telomere length via expression of an enzymatic complex called telomerase. Similarly, more than 85%–90% of cancer cells are found to upregulate the expression of telomerase, conferring them with the potential to proliferate indefinitely. Telomerase Reverse Transcriptase (TERT), the catalytic subunit of telomerase holoenzyme, is the rate-limiting factor in reconstituting telomerase activity in vivo. To date, the expression and function of the human Telomerase Reverse Transcriptase (hTERT) gene are known to be regulated at various molecular levels (including genetic, mRNA, protein and subcellular localization) by a number of diverse factors. Among these means of regulation, transcription modulation is the most important, as evident in its tight regulation in cancer cell survival as well as pluripotent stem cell maintenance and differentiation. Here, we discuss how hTERT gene transcription is regulated, mainly focusing on the contribution of trans-acting factors such as transcription factors and epigenetic modifiers, as well as genetic alterations in hTERT proximal promoter.
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A Hybrid Chalcone Combining the Trimethoxyphenyl and Isatinyl Groups Targets Multiple Oncogenic Proteins and Pathways in Hepatocellular Carcinoma Cells. PLoS One 2016; 11:e0161025. [PMID: 27525972 PMCID: PMC4985065 DOI: 10.1371/journal.pone.0161025] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Accepted: 07/28/2016] [Indexed: 12/20/2022] Open
Abstract
Small molecule inhibitors that can simultaneously inhibit multiple oncogenic proteins in essential pathways are promising therapeutic chemicals for hepatocellular carcinoma (HCC). To combine the anticancer effects of combretastatins, chalcones and isatins, we synthesized a novel hybrid molecule 3’,4’,5’-trimethoxy-5-chloro-isatinylchalcone (3MCIC). 3MCIC inhibited proliferation of cultured HepG2 cells, causing rounding-up of the cells and massive vacuole accumulation in the cytoplasm. Paxillin and focal adhesion plaques were downregulated by 3MCIC. Surprisingly, unlike the microtubule (MT)-targeting agent CA-4 that inhibits tubulin polymerization, 3MCIC stabilized tubulin polymers both in living cells and in cell lysates. 3MCIC treatment reduced cyclin B1, CDK1, p-CDK1/2, and Rb, but increased p53 and p21. Moreover, 3MCIC caused GSK3β degradation by promoting GSK3β-Ser9 phosphorylation. Nevertheless, 3MCIC inhibited the Wnt/β-catenin pathway by downregulating β-catenin, c-Myc, cyclin D1 and E2F1. 3MCIC treatment not only activated the caspase-3-dependent apoptotic pathway, but also caused massive autophagy evidenced by rapid and drastic changes of LC3 and p62. 3MCIC also promoted cleavage and maturation of the lysosomal protease cathepsin D. Using ligand-affinity chromatography (LAC), target proteins captured onto the Sephacryl S1000-C12-3MCIC resins were isolated and analyzed by mass spectrometry (MS). Some of the LAC-MS identified targets, i.e., septin-2, vimentin, pan-cytokeratin, nucleolin, EF1α1/2, EBP1 (PA2G4), cyclin B1 and GSK3β, were further detected by Western blotting. Moreover, both septin-2 and HIF-1α decreased drastically in 3MCIC-treated HepG2 cells. Our data suggest that 3MCIC is a promising anticancer lead compound with novel targeting mechanisms, and also demonstrate the efficiency of LAC-MS based target identification in anticancer drug development.
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Abstract
Telomerase activity is responsible for the maintenance of chromosome end structures (telomeres) and cancer cell immortality in most human malignancies, making telomerase an attractive therapeutic target. The rationale for targeting components of the telomerase holoenzyme has been strengthened by accumulating evidence indicating that these molecules have extra-telomeric functions in tumour cell survival and proliferation. This Review discusses current knowledge of the biogenesis, structure and multiple functions of telomerase-associated molecules intertwined with recent advances in drug discovery approaches. We also describe the fertile ground available for the pursuit of next-generation small-molecule inhibitors of telomerase.
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Affiliation(s)
- Greg M Arndt
- Australian Cancer Research Foundation (ACRF) Drug Discovery Centre for Childhood Cancer, Children's Cancer Institute Australia, Lowy Cancer Research Centre, University of New South Wales, Randwick, New South Wales 2031, Australia
| | - Karen L MacKenzie
- Personalised Medicine Program, Children's Cancer Institute Australia, Lowy Cancer Research Centre, University of New South Wales, Randwick, New South Wales 2031, Australia
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9
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Kim WH, Shen H, Jung DW, Williams DR. Some leopards can change their spots: potential repositioning of stem cell reprogramming compounds as anti-cancer agents. Cell Biol Toxicol 2016; 32:157-68. [DOI: 10.1007/s10565-016-9333-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Accepted: 04/28/2016] [Indexed: 01/14/2023]
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Harada G, Pattarawat P, Ito K, Matsumoto T, Hasegawa T, Katakura Y. Lactobacillus brevis T2102 suppresses the growth of colorectal cancer cells by activating SIRT1. J Funct Foods 2016. [DOI: 10.1016/j.jff.2016.01.016] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
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Bilsland AE, Pugliese A, Liu Y, Revie J, Burns S, McCormick C, Cairney CJ, Bower J, Drysdale M, Narita M, Sadaie M, Keith WN. Identification of a Selective G1-Phase Benzimidazolone Inhibitor by a Senescence-Targeted Virtual Screen Using Artificial Neural Networks. Neoplasia 2015; 17:704-715. [PMID: 26476078 PMCID: PMC4611071 DOI: 10.1016/j.neo.2015.08.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Revised: 08/28/2015] [Accepted: 08/31/2015] [Indexed: 12/29/2022]
Abstract
Cellular senescence is a barrier to tumorigenesis in normal cells, and tumor cells undergo senescence responses to genotoxic stimuli, which is a potential target phenotype for cancer therapy. However, in this setting, mixed-mode responses are common with apoptosis the dominant effect. Hence, more selective senescence inducers are required. Here we report a machine learning-based in silico screen to identify potential senescence agonists. We built profiles of differentially affected biological process networks from expression data obtained under induced telomere dysfunction conditions in colorectal cancer cells and matched these to a panel of 17 protein targets with confirmatory screening data in PubChem. We trained a neural network using 3517 compounds identified as active or inactive against these targets. The resulting classification model was used to screen a virtual library of ~2M lead-like compounds. One hundred and forty-seven virtual hits were acquired for validation in growth inhibition and senescence-associated β-galactosidase assays. Among the found hits, a benzimidazolone compound, CB-20903630, had low micromolar IC50 for growth inhibition of HCT116 cells and selectively induced senescence-associated β-galactosidase activity in the entire treated cell population without cytotoxicity or apoptosis induction. Growth suppression was mediated by G1 blockade involving increased p21 expression and suppressed cyclin B1, CDK1, and CDC25C. In addition, the compound inhibited growth of multicellular spheroids and caused severe retardation of population kinetics in long-term treatments. Preliminary structure-activity and structure clustering analyses are reported, and expression analysis of CB-20903630 against other cell cycle suppressor compounds suggested a PI3K/AKT-inhibitor-like profile in normal cells, with different pathways affected in cancer cells.
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Affiliation(s)
- Alan E Bilsland
- Institute of Cancer Sciences, University of Glasgow, Wolfson Wohl Cancer Research Centre, Garscube Estate, Switchback Road, Bearsden, Glasgow G61 1QH, UK
| | - Angelo Pugliese
- Cancer Research UK Beatson Institute, Garscube Estate, Switchback Road, Bearsden, Glasgow G61 1BD, UK
| | - Yu Liu
- Institute of Cancer Sciences, University of Glasgow, Wolfson Wohl Cancer Research Centre, Garscube Estate, Switchback Road, Bearsden, Glasgow G61 1QH, UK
| | - John Revie
- Institute of Cancer Sciences, University of Glasgow, Wolfson Wohl Cancer Research Centre, Garscube Estate, Switchback Road, Bearsden, Glasgow G61 1QH, UK
| | - Sharon Burns
- Institute of Cancer Sciences, University of Glasgow, Wolfson Wohl Cancer Research Centre, Garscube Estate, Switchback Road, Bearsden, Glasgow G61 1QH, UK
| | - Carol McCormick
- Institute of Cancer Sciences, University of Glasgow, Wolfson Wohl Cancer Research Centre, Garscube Estate, Switchback Road, Bearsden, Glasgow G61 1QH, UK
| | - Claire J Cairney
- Institute of Cancer Sciences, University of Glasgow, Wolfson Wohl Cancer Research Centre, Garscube Estate, Switchback Road, Bearsden, Glasgow G61 1QH, UK
| | - Justin Bower
- Cancer Research UK Beatson Institute, Garscube Estate, Switchback Road, Bearsden, Glasgow G61 1BD, UK
| | - Martin Drysdale
- Cancer Research UK Beatson Institute, Garscube Estate, Switchback Road, Bearsden, Glasgow G61 1BD, UK
| | - Masashi Narita
- University of Cambridge, Cancer Research UK Cambridge Institute, Li Ka Shing Centre Robinson Way, Cambridge, CB2 0RE, UK
| | - Mahito Sadaie
- Kyoto University, Graduate School of Biostudies, Yoshidakonoe-cho, Sakyo-ku Kyoto 606-8501 Japan
| | - W Nicol Keith
- Institute of Cancer Sciences, University of Glasgow, Wolfson Wohl Cancer Research Centre, Garscube Estate, Switchback Road, Bearsden, Glasgow G61 1QH, UK.
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12
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Yaswen P, MacKenzie KL, Keith WN, Hentosh P, Rodier F, Zhu J, Firestone GL, Matheu A, Carnero A, Bilsland A, Sundin T, Honoki K, Fujii H, Georgakilas AG, Amedei A, Amin A, Helferich B, Boosani CS, Guha G, Ciriolo MR, Chen S, Mohammed SI, Azmi AS, Bhakta D, Halicka D, Niccolai E, Aquilano K, Ashraf SS, Nowsheen S, Yang X. Therapeutic targeting of replicative immortality. Semin Cancer Biol 2015; 35 Suppl:S104-S128. [PMID: 25869441 PMCID: PMC4600408 DOI: 10.1016/j.semcancer.2015.03.007] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2014] [Revised: 03/06/2015] [Accepted: 03/13/2015] [Indexed: 12/15/2022]
Abstract
One of the hallmarks of malignant cell populations is the ability to undergo continuous proliferation. This property allows clonal lineages to acquire sequential aberrations that can fuel increasingly autonomous growth, invasiveness, and therapeutic resistance. Innate cellular mechanisms have evolved to regulate replicative potential as a hedge against malignant progression. When activated in the absence of normal terminal differentiation cues, these mechanisms can result in a state of persistent cytostasis. This state, termed “senescence,” can be triggered by intrinsic cellular processes such as telomere dysfunction and oncogene expression, and by exogenous factors such as DNA damaging agents or oxidative environments. Despite differences in upstream signaling, senescence often involves convergent interdependent activation of tumor suppressors p53 and p16/pRB, but can be induced, albeit with reduced sensitivity, when these suppressors are compromised. Doses of conventional genotoxic drugs required to achieve cancer cell senescence are often much lower than doses required to achieve outright cell death. Additional therapies, such as those targeting cyclin dependent kinases or components of the PI3K signaling pathway, may induce senescence specifically in cancer cells by circumventing defects in tumor suppressor pathways or exploiting cancer cells’ heightened requirements for telomerase. Such treatments sufficient to induce cancer cell senescence could provide increased patient survival with fewer and less severe side effects than conventional cytotoxic regimens. This positive aspect is countered by important caveats regarding senescence reversibility, genomic instability, and paracrine effects that may increase heterogeneity and adaptive resistance of surviving cancer cells. Nevertheless, agents that effectively disrupt replicative immortality will likely be valuable components of new combinatorial approaches to cancer therapy.
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Affiliation(s)
- Paul Yaswen
- Life Sciences Division, Lawrence Berkeley National Lab, Berkeley, CA, United States.
| | - Karen L MacKenzie
- Children's Cancer Institute Australia, Kensington, New South Wales, Australia.
| | | | | | | | - Jiyue Zhu
- Washington State University College of Pharmacy, Pullman, WA, United States.
| | | | | | - Amancio Carnero
- Instituto de Biomedicina de Sevilla, HUVR, Consejo Superior de Investigaciones Cientificas, Universdad de Sevilla, Seville, Spain.
| | | | | | | | | | | | | | - Amr Amin
- United Arab Emirates University, Al Ain, United Arab Emirates; Cairo University, Cairo, Egypt
| | - Bill Helferich
- University of Illinois at Urbana Champaign, Champaign, IL, United States
| | | | - Gunjan Guha
- SASTRA University, Thanjavur, Tamil Nadu, India
| | | | - Sophie Chen
- Ovarian and Prostate Cancer Research Trust, Guildford, Surrey, United Kingdom
| | | | - Asfar S Azmi
- Karmanos Cancer Institute, Wayne State University, Detroit, MI, United States
| | | | | | | | | | - S Salman Ashraf
- United Arab Emirates University, Al Ain, United Arab Emirates; Cairo University, Cairo, Egypt
| | | | - Xujuan Yang
- University of Illinois at Urbana Champaign, Champaign, IL, United States
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Tian X, Hou W, Bai S, Fan J, Tong H, Bai Y. XAV939 promotes apoptosis in a neuroblastoma cell line via telomere shortening. Oncol Rep 2014; 32:1999-2006. [PMID: 25190315 DOI: 10.3892/or.2014.3460] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2014] [Accepted: 08/19/2014] [Indexed: 11/05/2022] Open
Abstract
Telomeres, telomerase and tankyrase (TNKS) have an extremely important and special association with human cell aging and cancer. Telomerase activity is abnormally high in cancer cells and is accompanied by the overexpression of tankyrase 1 (TNKS1). TNKS1 is a positive regulator of telomerase activation and telomere extension in the human body, indicating that TNKS1 may be a possible therapeutic target for cancer. XAV939 is a small-molecule inhibitor of TNKS1. The objective of the present study was to investigate the apoptotic effect of XAV939 on the neuroblastoma (NB) SH-SY5Y cell line, as well as the change in telomere length and telomerase activity and elucidate the mechanism from this perspective. In the present study, we initially treated SH-SY5Y cells with XAV939 and RNA interference (RNAi)-TNKS1, and subsequently chose the optimal sequence for RNAi-TNKS1. We then measured the telomere length using quantitative real-time polymerase chain reaction (qPCR) assay, detected the telomerase activity using the ELISA kit, observed apoptotic morphology by transmission electron microscopy, and detected the percentages of apoptotic cells using flow cytometry and Hoechst 33342 staining. We also determined the invasive ability by a cell invasion assay. The results showed that short hairpin RNA-2 (shRNA-2) was the optimal sequence for RNAi-TNKS1. Treatment with both XAV939 and RNAi-TNKS1 shortened the telomere length, promoted apoptosis and reduced the invasive ability of the SH-SY5Y cells, yet had no effect on telomerase activity. XAV939 promoted apoptosis and reduced the invasiveness of SH-SY5Y cells dependent on telomere shortening, and further research should be conducted to clarify the exact mechanisms. This research may contribute to the cure of malignant NB using multi-targeted therapy with small-molecule agents.
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Affiliation(s)
- Xiaohong Tian
- Department of Tissue Engineering, College of Basic Medical Sciences, China Medical University, Shenyang, Liaoning 110001, P.R. China
| | - Weijian Hou
- Department of Tissue Engineering, College of Basic Medical Sciences, China Medical University, Shenyang, Liaoning 110001, P.R. China
| | - Shuling Bai
- Department of Tissue Engineering, College of Basic Medical Sciences, China Medical University, Shenyang, Liaoning 110001, P.R. China
| | - Jun Fan
- Department of Tissue Engineering, College of Basic Medical Sciences, China Medical University, Shenyang, Liaoning 110001, P.R. China
| | - Hao Tong
- Department of Tissue Engineering, College of Basic Medical Sciences, China Medical University, Shenyang, Liaoning 110001, P.R. China
| | - Yu Bai
- Department of Ophthalmology, The Second Hospital of Shijiazhuang, Shijiazhuang, Hebei 050051, P.R. China
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14
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Global expression profile of telomerase-associated genes in HeLa cells. Gene 2014; 547:211-7. [DOI: 10.1016/j.gene.2014.06.018] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Revised: 05/14/2014] [Accepted: 06/09/2014] [Indexed: 12/29/2022]
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15
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Mathematical model of a telomerase transcriptional regulatory network developed by cell-based screening: analysis of inhibitor effects and telomerase expression mechanisms. PLoS Comput Biol 2014; 10:e1003448. [PMID: 24550717 PMCID: PMC3923661 DOI: 10.1371/journal.pcbi.1003448] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2013] [Accepted: 11/30/2013] [Indexed: 12/16/2022] Open
Abstract
Cancer cells depend on transcription of telomerase reverse transcriptase (TERT). Many transcription factors affect TERT, though regulation occurs in context of a broader network. Network effects on telomerase regulation have not been investigated, though deeper understanding of TERT transcription requires a systems view. However, control over individual interactions in complex networks is not easily achievable. Mathematical modelling provides an attractive approach for analysis of complex systems and some models may prove useful in systems pharmacology approaches to drug discovery. In this report, we used transfection screening to test interactions among 14 TERT regulatory transcription factors and their respective promoters in ovarian cancer cells. The results were used to generate a network model of TERT transcription and to implement a dynamic Boolean model whose steady states were analysed. Modelled effects of signal transduction inhibitors successfully predicted TERT repression by Src-family inhibitor SU6656 and lack of repression by ERK inhibitor FR180204, results confirmed by RT-QPCR analysis of endogenous TERT expression in treated cells. Modelled effects of GSK3 inhibitor 6-bromoindirubin-3′-oxime (BIO) predicted unstable TERT repression dependent on noise and expression of JUN, corresponding with observations from a previous study. MYC expression is critical in TERT activation in the model, consistent with its well known function in endogenous TERT regulation. Loss of MYC caused complete TERT suppression in our model, substantially rescued only by co-suppression of AR. Interestingly expression was easily rescued under modelled Ets-factor gain of function, as occurs in TERT promoter mutation. RNAi targeting AR, JUN, MXD1, SP3, or TP53, showed that AR suppression does rescue endogenous TERT expression following MYC knockdown in these cells and SP3 or TP53 siRNA also cause partial recovery. The model therefore successfully predicted several aspects of TERT regulation including previously unknown mechanisms. An extrapolation suggests that a dominant stimulatory system may programme TERT for transcriptional stability. Tumour cells acquire the ability to divide and multiply indefinitely whereas normal cells can undergo only a limited number of divisions. The switch to immortalisation of the tumour cell is dependent on maintaining the integrity of telomere DNA which forms chromosome ends and is achieved through activation of the telomerase enzyme by turning on synthesis of the TERT gene, which is usually silenced in normal cells. Suppressing telomerase is toxic to cancer cells and it is widely believed that understanding TERT regulation could lead to potential cancer therapies. Previous studies have identified many of the factors which individually contribute to activate or repress TERT levels in cancer cells. However, transcription factors do not behave in isolation in cells, but rather as a complex co-operative network displaying inter-regulation. Therefore, full understanding of TERT regulation will require a broader view of the transcriptional network. In this paper we take a computational modelling approach to study TERT regulation at the network level. We tested interactions between 14 TERT-regulatory factors in an ovarian cancer cell line using a screening approach and developed a model to analyse which network interventions were able to silence TERT.
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16
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Sekaran V, Soares J, Jarstfer MB. Telomere Maintenance as a Target for Drug Discovery. J Med Chem 2013; 57:521-38. [DOI: 10.1021/jm400528t] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Vijay Sekaran
- Division of Chemical Biology
and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Joana Soares
- Division of Chemical Biology
and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Michael B. Jarstfer
- Division of Chemical Biology
and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
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17
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Sidestream smoke exposure increases the susceptibility of airway epithelia to adenoviral infection. PLoS One 2012; 7:e49930. [PMID: 23166798 PMCID: PMC3499494 DOI: 10.1371/journal.pone.0049930] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2012] [Accepted: 10/17/2012] [Indexed: 12/24/2022] Open
Abstract
Background Although significant epidemiological evidence indicates that cigarette smoke exposure increases the incidence and severity of viral infection, the molecular mechanisms behind the increased susceptibility of the respiratory tract to viral pathogens are unclear. Adenoviruses are non-enveloped DNA viruses and important causative agents of acute respiratory disease. The Coxsackievirus and adenovirus receptor (CAR) is the primary receptor for many adenoviruses. We hypothesized that cigarette smoke exposure increases epithelial susceptibility to adenovirus infection by increasing the abundance of apical CAR. Methodology and Findings Cultured human airway epithelial cells (CaLu-3) were used as a model to investigate the effect of sidestream cigarette smoke (SSS), mainstream cigarette smoke (MSS), or control air exposure on the susceptibility of polarized respiratory epithelia to adenoviral infection. Using a Cultex air-liquid interface exposure system, we have discovered novel differences in epithelial susceptibility between SSS and MSS exposures. SSS exposure upregulates an eight-exon isoform of CAR and increases adenoviral entry from the apical surface whilst MSS exposure is similar to control air exposure. Additionally, the level of cellular glycogen synthase kinase 3β (GSK3β) is downregulated by SSS exposure and treatment with a specific GSK3β inhibitor recapitulates the effects of SSS exposure on CAR expression and viral infection. Conclusions This is the first time that SSS exposure has been shown to directly enhance the susceptibility of a polarized epithelium to infection by a common respiratory viral pathogen. This work provides a novel understanding of the impact of SSS on the burden of respiratory viral infections and may lead to new strategies to alter viral infections. Moreover, since GSK3β inhibitors are under intense clinical investigation as therapeutics for a diverse range of diseases, studies such as these might provide insight to extend the use of clinically relevant therapeutics and increase the understanding of potential side effects.
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18
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The isoprenoid perillyl alcohol inhibits telomerase activity in prostate cancer cells. Biochimie 2012; 94:2639-48. [PMID: 22902867 DOI: 10.1016/j.biochi.2012.07.028] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2012] [Accepted: 07/31/2012] [Indexed: 12/16/2022]
Abstract
Isoprenoids are recognized for their ability to suppress carcinogenic processes in vivo and in vitro. We previously established that the isoprenoid, perillyl alcohol, acted mechanistically on translation of specific proteins through modulation of mechanistic target of rapamycin (mTOR) signaling. Telomerase-the enzyme responsible for immortalizing cells through the addition of telomeric repeats-is de-repressed early in an aspiring cancer cell. Here the effects of biologically-relevant concentrations and short incubations (1-16 h) of perillyl alcohol or the mTOR inhibitor, rapamycin, on telomerase activity were examined in prostate cancer cell lines. A rapid suppression of telomerase activity was observed (from ∼65% to >95%) determined by real-time quantitative telomerase repeat amplification protocol and confirmed by polyacrylamide gel-analysis. Using real-time reverse transcriptase-PCR, we demonstrated that human telomerase reverse transcriptase (hTERT) mRNA levels were unaltered. Western blot analysis revealed that hTERT protein levels decreased in response to perillyl alcohol or rapamycin. This decrease was partially blocked by pretreatment with a proteasome inhibitor MG-132, indicating that proteasomal degradation contributed to the loss of hTERT protein. No change in hTERT phosphorylation at Ser824 was observed, indicating the absence of cellular hTERT protein redistribution. These findings provide evidence for a unique link between nutrient- and macrolide-mediated regulation of mTOR and hTERT, a key enzyme that regulates DNA structure and stability.
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19
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Greider CW. Molecular biology. Wnt regulates TERT--putting the horse before the cart. Science 2012; 336:1519-20. [PMID: 22723405 DOI: 10.1126/science.1223785] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Carol W Greider
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
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20
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Bilsland AE, Cairney CJ, Keith WN. Targeting the telomere and shelterin complex for cancer therapy: current views and future perspectives. J Cell Mol Med 2012; 15:179-86. [PMID: 21199331 PMCID: PMC3822786 DOI: 10.1111/j.1582-4934.2010.01253.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Aberrant telomere homeostasis is essential for cell immortality, enabling cells to evade telomere dependent senescence. Disruption of telomere structure and function in cancer cells is highly toxic as shown by detailed pre-clinical evaluation of telomerase inhibitors. Under telomerase inhibition, cells must divide sufficiently frequently to allow one or more telomeres to shorten to an unprotected length. Functioning telomeres are disguised from the DNA damage machinery by DNA remodelling and other activities of the telomere binding complex shelterin. Direct interference with shelterin has been shown to result in cell killing and small molecules directly targeting telomere DNA also have anti-tumour effects partially dependent on shelterin disruption. However, shelterin components have not generally been regarded as therapeutic targets in their own right. In this review, we explore the possibilities for therapeutic targeting of the shelterin complex.
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Affiliation(s)
- Alan E Bilsland
- University of Glasgow, Institute of Cancer Sciences, Beatson Laboratories, Bearsden, Glasgow, UK
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21
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Abstract
Telomeres are stretches of repeated DNA sequences located at the ends of chromosomes that are necessary to prevent loss of gene-coding DNA regions during replication. Telomerase – the enzyme responsible for immortalising cancer cells through the addition of telomeric repeats – is active in ~90% of human cancers. Telomerase activity is inhibited by various phytochemicals such as isoprenoids, genistein, curcumin, epigallocatechin-3-gallate, resveratrol and others. Human TERT (telomerase reverse transcriptase – the rate-limiting component of telomerase), heat shock protein 90, Akt, p70 S6 kinase (S6K) and mammalian target of rapamycin (mTOR) form a physical and functional complex with one another. The inclusion of Akt, mTOR and S6K in the TERT complex is compelling evidence to support mTOR-mediated control of telomerase activity. This review will define the role of mTOR, the master regulator of protein translation, in telomerase regulation and provide additional insights into the numerous ways in which telomerase activity is hindered by phytochemicals.
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22
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Cairney CJ, Bilsland AE, Evans TRJ, Roffey J, Bennett DC, Narita M, Torrance CJ, Keith WN. Cancer cell senescence: a new frontier in drug development. Drug Discov Today 2012; 17:269-76. [PMID: 22314100 DOI: 10.1016/j.drudis.2012.01.019] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2011] [Revised: 01/19/2012] [Accepted: 01/24/2012] [Indexed: 12/21/2022]
Abstract
Senescence forms a universal block to tumorigenesis which impacts on all hallmarks of cancer, making it an attractive target for drug discovery. Therefore a strategy must be devised to focus this broad potential into a manageable drug discovery programme. Several issues remain to be addressed including the lack of robust senescence-inducing compounds and causally related biomarkers to measure cellular response. Here, we review the latest progress in translating senescence as a target for cancer therapy and some promising approaches to drug and biomarker discovery. Finally, we discuss the potential application of a senescence-induction therapy in a clinical setting.
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Affiliation(s)
- Claire J Cairney
- Institute of Cancer Sciences, University of Glasgow, CRUK Beatson Laboratories, Bearsden, Glasgow, UK
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23
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Bienvenut WV, Sumpton D, Martinez A, Lilla S, Espagne C, Meinnel T, Giglione C. Comparative large scale characterization of plant versus mammal proteins reveals similar and idiosyncratic N-α-acetylation features. Mol Cell Proteomics 2012; 11:M111.015131. [PMID: 22223895 DOI: 10.1074/mcp.m111.015131] [Citation(s) in RCA: 133] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
N-terminal modifications play a major role in the fate of proteins in terms of activity, stability, or subcellular compartmentalization. Such modifications remain poorly described and badly characterized in proteomic studies, and only a few comparison studies among organisms have been made available so far. Recent advances in the field now allow the enrichment and selection of N-terminal peptides in the course of proteome-wide mass spectrometry analyses. These targeted approaches unravel as a result the extent and nature of the protein N-terminal modifications. Here, we aimed at studying such modifications in the model plant Arabidopsis thaliana to compare these results with those obtained from a human sample analyzed in parallel. We applied large scale analysis to compile robust conclusions on both data sets. Our data show strong convergence of the characterized modifications especially for protein N-terminal methionine excision, co-translational N-α-acetylation, or N-myristoylation between animal and plant kingdoms. Because of the convergence of both the substrates and the N-α-acetylation machinery, it was possible to identify the N-acetyltransferases involved in such modifications for a small number of model plants. Finally, a high proportion of nuclear-encoded chloroplast proteins feature post-translational N-α-acetylation of the mature protein after removal of the transit peptide. Unlike animals, plants feature in a dedicated pathway for post-translational acetylation of organelle-targeted proteins. The corresponding machinery is yet to be discovered.
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Affiliation(s)
- Willy V Bienvenut
- CNRS, Centre de Recherche de Gif, Institut des Sciences du Végétal, F-91198 Gif-sur-Yvette cedex, France
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24
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Cerone MA, Burgess DJ, Naceur-Lombardelli C, Lord CJ, Ashworth A. High-throughput RNAi screening reveals novel regulators of telomerase. Cancer Res 2011; 71:3328-40. [PMID: 21531765 DOI: 10.1158/0008-5472.can-10-2734] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Telomerase is considered an attractive anticancer target on the basis of its common and specific activation in most human cancers. While direct telomerase inhibition is being explored as a therapeutic strategy, alternative strategies to target regulators of telomerase that could disrupt telomere maintenance and cancer cell proliferation are not yet available. Here, we report the findings of a high-throughput functional RNA interference screen to globally profile the contribution of kinases to telomerase activity (TA). This analysis identified a number of novel telomerase modulators, including ERK8 kinase, whose inhibition reduces TA and elicited characteristics of telomere dysfunction. Given that kinases represent attractive drug targets, we addressed the therapeutic implications of our findings, such as demonstrating how limiting TA via kinase blockade could sensitize cells to inhibition of the telomere-associated protein tankyrase. Taken together, our findings suggest novel combinatorial approaches to targeting telomere maintenance as a strategy for cancer therapy.
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25
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Fu Y, Zheng S, An N, Athanasopoulos T, Popplewell L, Liang A, Li K, Hu C, Zhu Y. β-catenin as a potential key target for tumor suppression. Int J Cancer 2011; 129:1541-51. [PMID: 21455986 DOI: 10.1002/ijc.26102] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2011] [Revised: 03/14/2011] [Accepted: 03/17/2011] [Indexed: 01/02/2023]
Abstract
β-catenin is a multifunctional protein identified to be pivotal in embryonic patterning, organogenesis and adult homeostasis. It plays a critical structural role in mediating cadherin junctions and is also an essential transcriptional co-activator in the canonical Wnt pathway. Evidence has been documented that both the canonical Wnt pathway and cadherin junctions are deregulated or impaired in a plethora of human malignancies. In the light of this, there has been a recent surge in elucidating the mechanisms underlying the etiology of cancer development from the perspective of β-catenin. Here, we focus on the emerging roles of β-catenin in the process of tumorigenesis by discussing novel functions of old players and new proteins, mechanisms identified to mediate or interact with β-catenin and the most recently unraveled clinical implications of β-catenin regulatory pathways toward tumor suppression.
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Affiliation(s)
- Yuejun Fu
- Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education, Institute of Biotechnology, Shanxi University, Taiyuan, People's Republic of China.
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26
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Tasseff R, Nayak S, Song SO, Yen A, Varner JD. Modeling and analysis of retinoic acid induced differentiation of uncommitted precursor cells. Integr Biol (Camb) 2011; 3:578-91. [PMID: 21437295 PMCID: PMC3685823 DOI: 10.1039/c0ib00141d] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Manipulation of differentiation programs has therapeutic potential in a spectrum of human cancers and neurodegenerative disorders. In this study, we integrated computational and experimental methods to unravel the response of a lineage uncommitted precursor cell-line, HL-60, to Retinoic Acid (RA). HL-60 is a human myeloblastic leukemia cell-line used extensively to study human differentiation programs. Initially, we focused on the role of the BLR1 receptor in RA-induced differentiation and G1/0-arrest in HL-60. BLR1, a putative G protein-coupled receptor expressed following RA exposure, is required for RA-induced cell-cycle arrest and differentiation and causes persistent MAPK signaling. A mathematical model of RA-induced cell-cycle arrest and differentiation was formulated and tested against BLR1 wild-type (wt) knock-out and knock-in HL-60 cell-lines with and without RA. The current model described the dynamics of 729 proteins and protein complexes interconnected by 1356 interactions. An ensemble strategy was used to compensate for uncertain model parameters. The ensemble of HL-60 models recapitulated the positive feedback between BLR1 and MAPK signaling. The ensemble of models also correctly predicted Rb and p47phox regulation and the correlation between p21-CDK4-cyclin D formation and G1/0-arrest following exposure to RA. Finally, we investigated the robustness of the HL-60 network architecture to structural perturbations and generated experimentally testable hypotheses for future study. Taken together, the model presented here was a first step toward a systematic framework for analysis of programmed differentiation. These studies also demonstrated that mechanistic network modeling can help prioritize experimental directions by generating falsifiable hypotheses despite uncertainty.
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Affiliation(s)
- Ryan Tasseff
- School of Chemical and Biomolecular Engineering, Cornell University, Ithaca NY, 14853
| | - Satyaprakash Nayak
- School of Chemical and Biomolecular Engineering, Cornell University, Ithaca NY, 14853
| | - Sang Ok Song
- School of Chemical and Biomolecular Engineering, Cornell University, Ithaca NY, 14853
| | - Andrew Yen
- Department of Biomedical Sciences, Cornell University, Ithaca NY, 14853
| | - Jeffrey D. Varner
- Cornell University, 244 Olin Hall, Ithaca NY, 14853. Fax: 607 255 9166; Tel: 607 255 4258
- School of Chemical and Biomolecular Engineering, Cornell University, Ithaca NY, 14853
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27
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Soo JK, Mackenzie Ross AD, Kallenberg DM, Milagre C, Heung Chong W, Chow J, Hill L, Hoare S, Collinson RS, Hossain M, Keith WN, Marais R, Bennett DC. Malignancy without immortality? Cellular immortalization as a possible late event in melanoma progression. Pigment Cell Melanoma Res 2011; 24:490-503. [PMID: 21418545 PMCID: PMC3123747 DOI: 10.1111/j.1755-148x.2011.00850.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Cell senescence is a permanent growth arrest following extended proliferation. Cultured cancer cells including metastatic melanoma cells often appear immortal (proliferate indefinitely), while uncultured benign nevi (moles) show senescence markers. Here, with new explantation methods, we investigated which classes of primary pigmented lesions are typically immortal. Nevi yielded a few proliferating cells, consistent with most nevus cells being senescent. No nevus culture (0/28) appeared immortal. Some thin and thick melanoma cultures proved immortal under these conditions, but surprisingly few (4/37). All arrested cultures displayed three senescence markers in some cells: β-galactosidase, nuclear p16, and heterochromatic foci/aggregates. However, melanoma cultures also showed features of telomeric crisis (arrest because of ultrashort telomeres). Moreover, crisis markers including anaphase bridges were frequent in uncultured vertical growth-phase (VGP) melanomas. Conversely, all immortal melanoma cultures expressed telomerase reverse transcriptase and telomerase, showing aneuploidy. The findings suggest that primary melanomas are typically precrisis, with immortalization/telomere maintenance as a late event.
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Affiliation(s)
- Julia K Soo
- Division of Biomedical Sciences, St. George's, University of London, UK
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28
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Lafferty-Whyte K, Bilsland A, Cairney CJ, Hanley L, Jamieson NB, Zaffaroni N, Oien KA, Burns S, Roffey J, Boyd SM, Keith WN. Scoring of senescence signalling in multiple human tumour gene expression datasets, identification of a correlation between senescence score and drug toxicity in the NCI60 panel and a pro-inflammatory signature correlating with survival advantage in peritoneal mesothelioma. BMC Genomics 2010; 11:532. [PMID: 20920304 PMCID: PMC3091681 DOI: 10.1186/1471-2164-11-532] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2010] [Accepted: 10/01/2010] [Indexed: 11/10/2022] Open
Abstract
Background Cellular senescence is a major barrier to tumour progression, though its role in pathogenesis of cancer and other diseases is poorly understood in vivo. Improved understanding of the degree to which latent senescence signalling persists in tumours might identify intervention strategies to provoke "accelerated senescence" responses as a therapeutic outcome. Senescence involves convergence of multiple pathways and requires ongoing dynamic signalling throughout its establishment and maintenance. Recent discovery of several new markers allows for an expression profiling approach to study specific senescence phenotypes in relevant tissue samples. We adopted a "senescence scoring" methodology based on expression profiles of multiple senescence markers to examine the degree to which signals of damage-associated or secretory senescence persist in various human tumours. Results We first show that scoring captures differential induction of damage or inflammatory pathways in a series of public datasets involving radiotherapy of colon adenocarcinoma, chemotherapy of breast cancer cells, replicative senescence of mesenchymal stem cells, and progression of melanoma. We extended these results to investigate correlations between senescence score and growth inhibition in response to ~1500 compounds in the NCI60 panel. Scoring of our own mesenchymal tumour dataset highlighted differential expression of secretory signalling pathways between distinct subgroups of MPNST, liposarcomas and peritoneal mesothelioma. Furthermore, a pro-inflammatory signature yielded by hierarchical clustering of secretory markers showed prognostic significance in mesothelioma. Conclusions We find that "senescence scoring" accurately reports senescence signalling in a variety of situations where senescence would be expected to occur and highlights differential expression of damage associated and secretory senescence pathways in a context-dependent manner.
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Affiliation(s)
- Kyle Lafferty-Whyte
- Centre for Oncology and Applied Pharmacology, University of Glasgow, Cancer Research UK Beatson Laboratories, Garscube Estate, Switchback Road, Bearsden, Glasgow G611BD, UK
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TCEAL7 inhibition of c-Myc activity in alternative lengthening of telomeres regulates hTERT expression. Neoplasia 2010; 12:405-14. [PMID: 20454512 DOI: 10.1593/neo.10180] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2010] [Revised: 03/03/2010] [Accepted: 03/05/2010] [Indexed: 11/18/2022] Open
Abstract
Replicative senescence forms a major barrier to tumor progression. Cancer cells bypass this by using one of the two known telomere maintenance mechanisms: telomerase or the recombination-based alternative lengthening of telomeres (ALT) mechanism. The molecular details of ALT are currently poorly understood. We have previously shown that telomerase is actively repressed through complex networks of kinase, gene expression, and chromatin regulation. In this study, we aimed to gain further understanding of the role of kinases in the regulation of telomerase expression in ALT cells. Using a whole human kinome small interfering RNA (siRNA) screen, we highlighted 106 kinases whose expression is linked to human telomerase reverse transcriptase (hTERT) promoter activity. Network modeling of transcriptional regulation implicated c-Myc as a key regulator of the 106 kinase hits. Given our previous observations of lower c-Myc activity in ALT cells, we further explored its potential to regulate telomerase expression in ALT. We found increased c-Myc binding at the hTERT promoter in telomerase-positive compared with ALT cells, although no expression differences in c-Myc, Mad, or Max were observed between ALT and telomerase-positive cells that could explain decreased c-Myc activity in ALT. Instead, we found increased expression of the c-Myc competitive inhibitor TCEAL7 in ALT cells and tumors and that alteration of TCEAL7 expression levels in ALT and telomerase-positive cells affects hTERT expression. Lower c-Myc activity in ALT may therefore be obtained through TCEAL7 regulation. Thus, TCEAL7 may present an interesting novel target for cancer therapy, which warrants further investigation.
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Degerman S, Siwicki JK, Osterman P, Lafferty-Whyte K, Keith WN, Roos G. Telomerase upregulation is a postcrisis event during senescence bypass and immortalization of two Nijmegen breakage syndrome T cell cultures. Aging Cell 2010; 9:220-35. [PMID: 20089118 DOI: 10.1111/j.1474-9726.2010.00550.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Our knowledge on immortalization and telomere biology is mainly based on genetically manipulated cells analyzed before and many population doublings post growth crisis. The general view is that growth crisis is telomere length (TL) dependent and that escape from crisis is coupled to increased expression of the telomerase reverse transcriptase (hTERT) gene, telomerase activity upregulation and TL stabilization. Here we have analyzed the process of spontaneous immortalization of human T cells, regarding pathways involved in senescence and telomerase regulation. Two Nijmegen breakage syndrome (NBS) T cell cultures (S3R and S4) showed gradual telomere attrition until a period of growth crisis followed by the outgrowth of immortalized cells. Whole genome expression analysis indicated differences between pre-, early post- and late postcrisis cells. Early postcrisis cells demonstrated a logarithmic growth curve, very short telomeres and, notably, no increase in hTERT or telomerase activity despite downregulation of several negative hTERT regulators (e.g. FOS, JUN D, SMAD3, RUNX2, TNF-a and TGFb-R2). Thereafter, cMYC mRNA increased in parallel with increased hTERT expression, telomerase activity and elongation of short telomeres, indicating a step-wise activation of hTERT transcription involving reduction of negative regulators followed by activation of positive regulator(s). Gene expression analysis indicated that cells escaped growth crisis by deregulated DNA damage response and senescence controlling genes, including downregulation of ATM, CDKN1B (p27), CDKN2D (p19) and ASF1A and upregulation of CDK4, TWIST1, TP73L (p63) and SYK. Telomerase upregulation was thus found to be uncoupled to escape of growth crisis but rather a later event in the immortalization process of NBS T cell cultures.
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Affiliation(s)
- Sofie Degerman
- Department of Medical Biosciences, Pathology, Umeå University, SE-90185 Umeå, Sweden
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Bennett LB, Taylor KH, Arthur GL, Rahmatpanah FB, Hooshmand SI, Caldwell CW. Epigenetic regulation of WNT signaling in chronic lymphocytic leukemia. Epigenomics 2010; 2:53-70. [PMID: 20473358 PMCID: PMC2869094 DOI: 10.2217/epi.09.43] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Certain WNT and WNT network target genes are expressed at higher or lower levels in chronic lymphocytic leukemia compared with normal B-cells. This includes upregulation of nuclear complex genes, as well as genes for cytoplasmic proteins and WNT ligands and their cognate receptors. In addition, epigenetic silencing of several negative regulators of the WNT pathway have been identified. The balance between epigenetic downregulation of negative effector genes and increased expression of positive effector genes demonstrate that the epigenetic downregulation of WNT antagonists is one mechanism, perhaps the main mechanism, that is permissive to active WNT signaling in chronic lymphocytic leukemia. Moreover, constitutive activation of the WNT network and target genes is likely to impact on additional interacting signaling pathways. Based on published studies, we propose a model of WNT signaling that involves mainly permissive expression, and sometimes overexpression, of positive effectors and downregulation of negative regulators in the network. In this model, DNA methylation, histone modifications and altered expression of microRNA molecules interact to allow continuous WNT signaling.
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Affiliation(s)
| | | | | | | | | | - Charles W Caldwell
- Author for correspondence: Department of Pathology & Anatomical Sciences, Ellis Fischel Cancer Center, University of Missouri, 115 Business Loop I-70 West, Columbia, MO 65203, USA, Tel.: +1 573 882 1234, Fax: +1 573 884 5206,
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