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Ismail A, Lewis E, Sjödin B, Mannervik B. Characterization of Dog Glutathione Transferase P1-1, an Enzyme Relevant to Veterinary Medicine. Int J Mol Sci 2021; 22:ijms22084079. [PMID: 33920860 PMCID: PMC8071248 DOI: 10.3390/ijms22084079] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 04/09/2021] [Accepted: 04/12/2021] [Indexed: 11/25/2022] Open
Abstract
Glutathione transferases (GSTs) form a family of detoxication enzymes instrumental in the inactivation and elimination of electrophilic mutagenic and carcinogenic compounds. The Pi class GST P1-1 is present in most tissues and is commonly overexpressed in neoplastic cells. GST P1-1 in the dog, Canis lupus familiaris, has merits as a marker for tumors and as a target for enzyme-activated prodrugs. We produced the canine enzyme CluGST P1-1 by heterologous bacterial expression and verified its cross-reactivity with antihuman-GST P1-1 antibodies. The catalytic activity with alternative substrates of biological significance was determined, and the most active substrate found was benzyl isothiocyanate. Among established GST inhibitors, Cibacron Blue showed positive cooperativity with an IC50 value of 43 nM. Dog GST P1-1 catalyzes activation of the prodrug Telcyta, but the activity is significantly lower than that of the human homolog.
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Affiliation(s)
- Aram Ismail
- Department of Biochemistry and Biophysics, Arrhenius Laboratories, Stockholm University, SE-10691 Stockholm, Sweden; (A.I.); (B.S.)
| | - Elizabeth Lewis
- College of Liberal Arts & Sciences, University of Illinois Urbana-Champaign, Champaign, IL 61801, USA;
| | - Birgitta Sjödin
- Department of Biochemistry and Biophysics, Arrhenius Laboratories, Stockholm University, SE-10691 Stockholm, Sweden; (A.I.); (B.S.)
| | - Bengt Mannervik
- Department of Biochemistry and Biophysics, Arrhenius Laboratories, Stockholm University, SE-10691 Stockholm, Sweden; (A.I.); (B.S.)
- Correspondence:
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2
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Abstract
The rediscovery and reinterpretation of the Warburg effect in the year 2000 occulted for almost a decade the key functions exerted by mitochondria in cancer cells. Until recent times, the scientific community indeed focused on constitutive glycolysis as a hallmark of cancer cells, which it is not, largely ignoring the contribution of mitochondria to the malignancy of oxidative and glycolytic cancer cells, being Warburgian or merely adapted to hypoxia. In this review, we highlight that mitochondria are not only powerhouses in some cancer cells, but also dynamic regulators of life, death, proliferation, motion and stemness in other types of cancer cells. Similar to the cells that host them, mitochondria are capable to adapt to tumoral conditions, and probably to evolve to ‘oncogenic mitochondria' capable of transferring malignant capacities to recipient cells. In the wider quest of metabolic modulators of cancer, treatments have already been identified targeting mitochondria in cancer cells, but the field is still in infancy.
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Affiliation(s)
- Debora Grasso
- Pole of Pharmacology & Therapeutics, Institut de Recherche Expérimentale et Clinique (IREC), Université catholique de Louvain (UCLouvain), Brussels, Belgium
| | - Luca X Zampieri
- Pole of Pharmacology & Therapeutics, Institut de Recherche Expérimentale et Clinique (IREC), Université catholique de Louvain (UCLouvain), Brussels, Belgium
| | - Tânia Capelôa
- Pole of Pharmacology & Therapeutics, Institut de Recherche Expérimentale et Clinique (IREC), Université catholique de Louvain (UCLouvain), Brussels, Belgium
| | - Justine A Van de Velde
- Pole of Pharmacology & Therapeutics, Institut de Recherche Expérimentale et Clinique (IREC), Université catholique de Louvain (UCLouvain), Brussels, Belgium
| | - Pierre Sonveaux
- Pole of Pharmacology & Therapeutics, Institut de Recherche Expérimentale et Clinique (IREC), Université catholique de Louvain (UCLouvain), Brussels, Belgium
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Glutathione Transferases: Potential Targets to Overcome Chemoresistance in Solid Tumors. Int J Mol Sci 2018; 19:ijms19123785. [PMID: 30487385 PMCID: PMC6321424 DOI: 10.3390/ijms19123785] [Citation(s) in RCA: 76] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Revised: 11/23/2018] [Accepted: 11/24/2018] [Indexed: 12/14/2022] Open
Abstract
Multifunctional enzymes glutathione transferases (GSTs) are involved in the development of chemoresistance, thus representing a promising target for a novel approach in cancer treatment. This superfamily of polymorphic enzymes exhibits extraordinary substrate promiscuity responsible for detoxification of numerous conventional chemotherapeutics, at the same time regulating signaling pathways involved in cell proliferation and apoptosis. In addition to upregulated GST expression, different cancer cell types have a unique GST signature, enabling targeted selectivity for isoenzyme specific inhibitors and pro-drugs. As a result of extensive research, certain GST inhibitors are already tested in clinical trials. Catalytic properties of GST isoenzymes are also exploited in bio-activation of specific pro-drugs, enabling their targeted accumulation in cancer cells with upregulated expression of the appropriate GST isoenzyme. Moreover, the latest approach to increase specificity in treatment of solid tumors is development of GST pro-drugs that are derivatives of conventional anti-cancer drugs. A future perspective is based on the design of new drugs, which would selectively target GST overexpressing cancers more prone to developing chemoresistance, while decreasing side effects in off-target cells.
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Dong SC, Sha HH, Xu XY, Hu TM, Lou R, Li H, Wu JZ, Dan C, Feng J. Glutathione S-transferase π: a potential role in antitumor therapy. Drug Des Devel Ther 2018; 12:3535-3547. [PMID: 30425455 PMCID: PMC6204874 DOI: 10.2147/dddt.s169833] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Glutathione S-transferase π (GSTπ) is a Phase II metabolic enzyme that is an important facilitator of cellular detoxification. Traditional dogma asserts that GSTπ functions to catalyze glutathione (GSH)-substrate conjunction to preserve the macromolecule upon exposure to oxidative stress, thus defending cells against various toxic compounds. Over the past 20 years, abnormal GSTπ expression has been linked to the occurrence of tumor resistance to chemotherapy drugs, demonstrating that this enzyme possesses functions beyond metabolism. This revelation reveals exciting possibilities in the realm of drug discovery, as GSTπ inhibitors and its prodrugs offer a feasible strategy in designing anticancer drugs with the primary purpose of reversing tumor resistance. In connection with the authors' current research, we provide a review on the biological function of GSTπ and current developments in GSTπ-targeting drugs, as well as the prospects of future strategies.
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Affiliation(s)
- Shu-Chen Dong
- Jiangsu Cancer Hospital and Jiangsu Institute of Cancer Research and Nanjing Medical University Affiliated Cancer Hospital, Nanjing 210009, China, ;
| | - Huan-Huan Sha
- Jiangsu Cancer Hospital and Jiangsu Institute of Cancer Research and Nanjing Medical University Affiliated Cancer Hospital, Nanjing 210009, China, ;
| | - Xiao-Yue Xu
- Jiangsu Cancer Hospital and Jiangsu Institute of Cancer Research and Nanjing Medical University Affiliated Cancer Hospital, Nanjing 210009, China, ;
| | - Tian-Mu Hu
- Department of Biological Science, Purdue University, West Lafayette, IN, USA
| | - Rui Lou
- Jiangsu Cancer Hospital and Jiangsu Institute of Cancer Research and Nanjing Medical University Affiliated Cancer Hospital, Nanjing 210009, China, ;
| | - Huizi Li
- Jiangsu Cancer Hospital and Jiangsu Institute of Cancer Research and Nanjing Medical University Affiliated Cancer Hospital, Nanjing 210009, China, ;
| | - Jian-Zhong Wu
- Jiangsu Cancer Hospital and Jiangsu Institute of Cancer Research and Nanjing Medical University Affiliated Cancer Hospital, Nanjing 210009, China, ;
| | - Chen Dan
- Jiangsu Cancer Hospital and Jiangsu Institute of Cancer Research and Nanjing Medical University Affiliated Cancer Hospital, Nanjing 210009, China, ;
| | - Jifeng Feng
- Jiangsu Cancer Hospital and Jiangsu Institute of Cancer Research and Nanjing Medical University Affiliated Cancer Hospital, Nanjing 210009, China, ;
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5
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Corso CR, Acco A. Glutathione system in animal model of solid tumors: From regulation to therapeutic target. Crit Rev Oncol Hematol 2018; 128:43-57. [DOI: 10.1016/j.critrevonc.2018.05.014] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Revised: 04/10/2018] [Accepted: 05/16/2018] [Indexed: 02/07/2023] Open
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Nunes SC, Serpa J. Glutathione in Ovarian Cancer: A Double-Edged Sword. Int J Mol Sci 2018; 19:ijms19071882. [PMID: 29949936 PMCID: PMC6073569 DOI: 10.3390/ijms19071882] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Revised: 06/15/2018] [Accepted: 06/25/2018] [Indexed: 01/21/2023] Open
Abstract
Glutathione (GSH) has several roles in a cell, such as a reactive oxygen species (ROS) scavenger, an intervenient in xenobiotics metabolism and a reservoir of cysteine. All of these activities are important in the maintenance of normal cells homeostasis but can also constitute an advantage for cancer cells, allowing disease progression and resistance to therapy. Ovarian cancer is the major cause of death from gynaecologic disease and the second most common gynaecologic malignancy worldwide. In over 50 years, the overall survival of patients diagnosed with epithelial ovarian cancer has not changed, regardless of the efforts concerning early detection, radical surgery and new therapeutic approaches. Late diagnosis and resistance to therapy are the main causes of this outcome, and GSH is profoundly associated with chemoresistance to platinum salts, which, together with taxane-based chemotherapy and surgery, are the main therapy strategies in ovarian cancer treatment. Herein, we present some insights into the role of GSH in the poor prognosis of ovarian cancer, and also point out how some strategies underlying the dependence of ovarian cancer cells on GSH can be further used to improve the effectiveness of therapy.
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Affiliation(s)
- Sofia C Nunes
- Centro de Estudos de Doenças Crónicas (CEDOC), NOVA Medical School/Faculdade de Ciências Médicas, Universidade Nova de Lisboa, Campo Mártires da Pátria 130, 1169-056 Lisboa, Portugal.
- Unidade de Investigação em Patobiologia Molecular do Instituto Português de Oncologia de Lisboa Francisco Gentil (IPOLFG), Rua Prof. Lima Basto, 1099-023 Lisboa, Portugal.
| | - Jacinta Serpa
- Centro de Estudos de Doenças Crónicas (CEDOC), NOVA Medical School/Faculdade de Ciências Médicas, Universidade Nova de Lisboa, Campo Mártires da Pátria 130, 1169-056 Lisboa, Portugal.
- Unidade de Investigação em Patobiologia Molecular do Instituto Português de Oncologia de Lisboa Francisco Gentil (IPOLFG), Rua Prof. Lima Basto, 1099-023 Lisboa, Portugal.
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Huang Z, Wu J, Zou Y, Yuan H, Zhang Y, Fei Y, Bhardwaj A, Kaur J, Knaus EE, Zhang Y. Glutathione S-Transferase π-Activatable O2-(Sulfonylethyl Derived) Diazeniumdiolates Potently Suppress Melanoma in Vitro and in Vivo. J Med Chem 2018; 61:1833-1844. [DOI: 10.1021/acs.jmedchem.7b01178] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Zhangjian Huang
- State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Drug Discovery for Metabolic Diseases, Center of Drug Discovery, China Pharmaceutical University, Nanjing 210009, China
| | - Jianbing Wu
- State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Drug Discovery for Metabolic Diseases, Center of Drug Discovery, China Pharmaceutical University, Nanjing 210009, China
| | - Yu Zou
- State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Drug Discovery for Metabolic Diseases, Center of Drug Discovery, China Pharmaceutical University, Nanjing 210009, China
| | - Haoliang Yuan
- State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Drug Discovery for Metabolic Diseases, Center of Drug Discovery, China Pharmaceutical University, Nanjing 210009, China
| | - Yinqiu Zhang
- State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Drug Discovery for Metabolic Diseases, Center of Drug Discovery, China Pharmaceutical University, Nanjing 210009, China
| | - Yue Fei
- State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Drug Discovery for Metabolic Diseases, Center of Drug Discovery, China Pharmaceutical University, Nanjing 210009, China
| | - Atul Bhardwaj
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta T6G 2E1, Canada
| | - Jatinder Kaur
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta T6G 2E1, Canada
| | - Edward E. Knaus
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta T6G 2E1, Canada
| | - Yihua Zhang
- State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Drug Discovery for Metabolic Diseases, Center of Drug Discovery, China Pharmaceutical University, Nanjing 210009, China
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8
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Bräutigam M, Teusch N, Schenk T, Sheikh M, Aricioglu RZ, Borowski SH, Neudörfl JM, Baumann U, Griesbeck AG, Pietsch M. Selective Inhibitors of Glutathione Transferase P1 with Trioxane Structure as Anticancer Agents. ChemMedChem 2015; 10:629-39. [DOI: 10.1002/cmdc.201402553] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2014] [Indexed: 11/09/2022]
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Dourado DFAR, Fernandes PA, Ramos MJ, Mannervik B. Mechanism of glutathione transferase P1-1-catalyzed activation of the prodrug canfosfamide (TLK286, TELCYTA). Biochemistry 2013; 52:8069-78. [PMID: 24066958 DOI: 10.1021/bi4005705] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Canfosfamide (TLK286, TELCYTA) is a prodrug that upon activation by glutathione transferase P1-1 (GST P1-1) yields an anticancer alkylating agent and a glutathione derivative. The rationale underlying the use of TLK286 in chemotherapy is that tumor cells overexpressing GST P1-1 will be locally exposed to the released alkylating agent with limited collateral toxicity to the surrounding normal tissues. TLK286 has demonstrated clinical effects in phase II and III clinical trials for the treatment of malignancies, such as ovarian cancer, nonsmall cell lung cancer, and breast cancer, as a single agent and in combination with other chemotherapeutic agents. In spite of these promising results, the detailed mechanism of GST P1-1 activation of the prodrug has not been elucidated. Here, we propose a mechanism for the TLK286 activation by GST P1-1 on the basis of density functional theory (DFT) and on potential of mean force (PMF) calculations. A catalytic water molecule is instrumental to the activation by forming a network of intermolecular interactions between the active-site Tyr7 hydroxyl and the sulfone and COO(-) groups of TLK286. The results obtained are consistent with the available experimental kinetic data and provide an atomistic understanding of the TLK286 activation mechanism.
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Affiliation(s)
- Daniel F A R Dourado
- REQUIMTE/Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto , Rua do Campo Alegre s/n, 4169-007 Porto, Portugal
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Tomao F, Papa A, Rossi L, Caruso D, Panici PB, Venezia M, Tomao S. Current status of bevacizumab in advanced ovarian cancer. Onco Targets Ther 2013; 6:889-99. [PMID: 23901283 PMCID: PMC3724566 DOI: 10.2147/ott.s46301] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Ovarian cancer is the most lethal gynecological cancer, mainly because of the delay in diagnosis. Recently, much effort has been put into investigating and introducing novel targeted agents into clinical practice, with the aim of improving prognosis and quality of life. Angiogenesis is a possible target. The aim of this review is to investigate the most common molecular pathways of angiogenesis, which have provided novel targets for tailored therapy in patients with ovarian cancer. These therapeutic strategies include monoclonal antibodies and tyrosine-kinase inhibitors. These drugs have as molecular targets vascular endothelial growth factor, vascular endothelial growth factor receptors, platelet-derived growth factor, fibroblast growth factor, and angiopoietin. Bevacizumab was investigated in several Phase III studies, with interesting results. Today, there is strong evidence for introducing bevacizumab in the treatment of patients with advanced and recurrent ovarian cancer. Nevertheless, further investigations and large clinical trials are needed to understand the safety and effectiveness of bevacizumab, the optimal duration and timing of treatment, and activity in association with other chemotherapeutic and targeted agents. It also is necessary to identify biologic factors predictive of efficacy to choose the most appropriate antiangiogenic agent in the integrated treatment of epithelial ovarian cancer.
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Affiliation(s)
- Federica Tomao
- Department of Gynaecology and Obstetrics, “Sapienza” University of Rome, Policlinico “Umberto I,” Rome, Italy
| | - Anselmo Papa
- Department of Medico-Surgical Sciences and Biotechnologies, “Sapienza” University of Rome, Oncology Unit, “ICOT,” Latina, Italy
| | - Luigi Rossi
- Department of Medico-Surgical Sciences and Biotechnologies, “Sapienza” University of Rome, Oncology Unit, “ICOT,” Latina, Italy
| | - Davide Caruso
- Department of Medico-Surgical Sciences and Biotechnologies, “Sapienza” University of Rome, Oncology Unit, “ICOT,” Latina, Italy
| | - Pierluigi Benedetti Panici
- Department of Gynaecology and Obstetrics, “Sapienza” University of Rome, Policlinico “Umberto I,” Rome, Italy
| | - Martina Venezia
- Department of Medico-Surgical Sciences and Biotechnologies, “Sapienza” University of Rome, Oncology Unit, “ICOT,” Latina, Italy
| | - Silverio Tomao
- Department of Medico-Surgical Sciences and Biotechnologies, “Sapienza” University of Rome, Oncology Unit, “ICOT,” Latina, Italy
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Ruzza P, Calderan A. Glutathione Transferase (GST)-Activated Prodrugs. Pharmaceutics 2013; 5:220-31. [PMID: 24300447 PMCID: PMC3834953 DOI: 10.3390/pharmaceutics5020220] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Revised: 03/21/2013] [Accepted: 03/22/2013] [Indexed: 12/19/2022] Open
Abstract
Glutathione transferase (formerly GST) catalyzes the inactivation of various electrophile-producing anticancer agents via conjugation to the tripeptide glutathione. Moreover, several data link the overexpression of some GSTs, in particular GSTP1-1, to both natural and acquired resistance to various structurally unrelated anticancer drugs. Tumor overexpression of these proteins has provided a rationale for the search of GST inhibitors and GST activated cytotoxic prodrugs. In the present review we discuss the current structural and pharmacological knowledge of GST-activated cytotoxic compounds.
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Affiliation(s)
- Paolo Ruzza
- Institute of Biomolecular Chemistry of CNR, Padova Unit, Via Marzolo 1, Padova 35131, Italy.
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12
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Backos DS, Franklin CC, Reigan P. The role of glutathione in brain tumor drug resistance. Biochem Pharmacol 2011; 83:1005-12. [PMID: 22138445 DOI: 10.1016/j.bcp.2011.11.016] [Citation(s) in RCA: 132] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2011] [Revised: 11/18/2011] [Accepted: 11/18/2011] [Indexed: 12/24/2022]
Abstract
Chemotherapy is central to the current treatment modality for primary human brain tumors, but despite high-dose and intensive treatment regimens there has been little improvement in patient outcome. The development of tumor chemoresistance has been proposed as a major contributor to this lack of response. While there have been some improvements in our understanding of the molecular mechanisms underlying brain tumor drug resistance over the past decade, the contribution of glutathione (GSH) and the GSH-related enzymes to drug resistance in brain tumors have been largely overlooked. GSH constitutes a major antioxidant defense system in the brain and together with the GSH-related enzymes plays an important role in protecting cells against free radical damage and dictating tumor cell response to adjuvant cancer therapies, including irradiation and chemotherapy. Glutamate cysteine ligase (GCL), glutathione synthetase (GS), glutathione peroxidase (GPx), glutathione reductase (GR), glutathione-S-transferases (GST), and GSH complex export transporters (GS-X pumps) are major components of the GSH-dependent enzyme system that function in a dynamic cascade to maintain redox homeostasis. In many tumors, the GSH system is often dysregulated, resulting in a more drug resistant phenotype. This is commonly associated with GST-mediated GSH conjugation of various anticancer agents leading to the formation of less toxic GSH-drug complexes, which can be readily exported from the cell. Advances in our understanding of the mechanisms of drug resistance and patient selection based on biomarker profiles will be crucial to adapt therapeutic strategies and improve outcomes for patients with primary malignant brain tumors.
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Affiliation(s)
- Donald S Backos
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Denver, Aurora, 80045, United States
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Abstract
Although ovarian cancer is often a chemosensitive malignancy, patients who are resistant to platinum-based chemotherapy represent a therapeutic challenge. Currently, the only drugs that are US FDA approved to treat this subset of patients are paclitaxel, pegylated liposomal doxorubicin (PLD) and topotecan. The response rates with these agents is in the 10-15% range and overall survival is around 12 months. Other drugs that have shown some activity in platinum-resistant ovarian cancer include the taxane analogues, oral etoposide, pemetrexed and bevacizumab. Unfortunately, randomized phase III trials of second-line chemotherapy in patients with platinum-resistant ovarian cancer have not shown an advantage over existing therapy with respect to progression-free survival or overall survival. The only trial that has reported a significant progression-free survival advantage over standard therapy is a randomized phase II trial of PLD with or without EC145, a folate-linked vinca alkaloid. Final survival results of this trial are pending.
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Tew KD, Townsend DM. Regulatory functions of glutathione S-transferase P1-1 unrelated to detoxification. Drug Metab Rev 2011; 43:179-93. [PMID: 21351850 DOI: 10.3109/03602532.2011.552912] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Glutathione S-transferase P1-1 (GSTP) is one member of the family of GSTs and is ubiquitously expressed in human tissues. The literature is replete with reports of high levels of GSTP linked either with cancer incidence or drug resistance, and yet no entirely cogent explanation for these correlations exists. The catalytic detoxification properties of the GST isozyme family have been a primary research focus for the last four decades. However, it has become apparent that they have undergone structural and functional convergence where evolutionary selective pressures have favored the emergence of noncatalytic properties of GSTP that has imbued this isozyme with expanded biological importance. For example, GSTP has now been linked with two cell-signaling functions that are critical to survival. Through protein:protein interactions, GSTP can sequester c-jun N-terminal kinase (JNK) and act as a negative regulator of this stress kinase. Pharmacologically, this activity has been linked with the activity of GSTP inhibitors in stimulating myeloproliferation. In addition, GSTP is linked with the forward S-glutathionylation reaction, a post-translational modification that impacts the function/activity of a number of proteins. Catalytic reversal of S-glutathionylation is well characterized, but the role of GSTP in catalyzing the forward reaction contributes to the "glutathionylation cycle." Moreover, GSTP is itself susceptible to S-glutathionylation, providing an autoregulatory loop for the cycle. Because oxidative stress regulates both S-glutathionylation and JNK-signaling pathways, such links may help to explain the aberrant patterns of GSTP expression in the cancer phenotype. As such, there is an ongoing preclinical and clinical platform of drug discovery and development around GSTP.
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Affiliation(s)
- Kenneth D Tew
- Department of Cell and Molecular Pharmacology and Experimental Therapeutics, Medical University of South Carolina, 173 Ashley Avenue, Charleston, SC 29425-5050, USA.
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15
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Köberle B, Tomicic MT, Usanova S, Kaina B. Cisplatin resistance: Preclinical findings and clinical implications. Biochim Biophys Acta Rev Cancer 2010; 1806:172-82. [PMID: 20647037 DOI: 10.1016/j.bbcan.2010.07.004] [Citation(s) in RCA: 183] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2010] [Revised: 07/07/2010] [Accepted: 07/12/2010] [Indexed: 02/03/2023]
Affiliation(s)
- Beate Köberle
- Institute of Toxicology, University Medical Center Mainz, Germany.
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16
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Brüning A, Mylonas I. New emerging drugs targeting the genomic integrity and replication machinery in ovarian cancer. Arch Gynecol Obstet 2010; 283:1087-96. [PMID: 21082186 DOI: 10.1007/s00404-010-1757-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2010] [Accepted: 10/29/2010] [Indexed: 12/12/2022]
Abstract
INTRODUCTION Ovarian cancer is a difficult to treat cancer entity with a high relapse rate. After initial surgery and chemotherapy, only a few options for therapeutic treatment remain in case of cancer recurrence. New treatment options with improved efficacies to circumvent acquired or pre-existing drug resistance are needed. MATERIALS This survey focuses on new prospective drugs for ovarian cancer treatment that either cause direct damage to the nuclear DNA or inhibit chromosome segregation by acting as mitotic spindle inhibitors. RESULTS Among a plethora of currently tested and proposed new drugs for ovarian cancer treatment, only a few appear to meet the criteria of sufficient and reliable efficacy with tolerable toxicity. These include the naturally occurring DNA-alkylating alkaloid trabectedin, the nitrogen mustard prodrug canfosfamide, and the synthetic kinase inhibitor ON-01910. The latter inhibits mitotic spindle formation without a direct tubulin interaction, avoiding adverse neurotoxic reactions common to the taxanes. Further, epothilones and oxaliplatin, already approved drugs for other cancer entities, show promising activity against ovarian cancer; they are even of interest as a first-line treatment option. DISCUSSION Although the current focus and interest of modern cancer drug design tends to be more specific and targeted therapies, including therapeutic antibodies and specific small molecules to inhibit growth-, apoptosis-, and angiogenesis-regulating signalling cascades, the main target for ovarian cancer treatment appears to remain its basic, though uncontrolled working proliferation machinery. This includes the current gold standard for ovarian cancer chemotherapy, carboplatin, and taxanes, as well as the few remaining alternatives, such as topotecan, doxorubicin, and gemcitabine, which all rely on their ability to bind to or to modify the DNA or the chromosome-separating spindle apparatus. Thus, the genomic integrity and replication machinery of ovarian cancer cells prove to represent an established, and obviously still effective target to be tackled for ovarian cancer treatment.
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Affiliation(s)
- Ansgar Brüning
- 1st Department of Obstetrics and Gynaecology, Ludwig-Maximilians-University Munich, Maistrasse 11, Munich 80337, Germany
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Matsuo K, Lin YG, Roman LD, Sood AK. Overcoming platinum resistance in ovarian carcinoma. Expert Opin Investig Drugs 2010; 19:1339-54. [PMID: 20815774 PMCID: PMC2962713 DOI: 10.1517/13543784.2010.515585] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
IMPORTANCE OF THE FIELD Ovarian cancer remains a deadly malignancy because most patients develop recurrent disease that is resistant to chemotherapy, including platinum. Because response rates for current treatment regimens are relatively similar and unfortunately low, no standard chemotherapy for platinum-resistant ovarian cancer exists. AREAS COVERED IN THIS REVIEW A systematic literature review of clinical studies published between January 2005 and March 2010 was conducted using search engines, PubMed and MEDLINE with the entry keywords 'ovarian cancer' and 'platinum resistance'. This search revealed 40 clinical trials (1793 patients). WHAT THE READER WILL GAIN Gemcitabine was the most common drug used in clinical trials reporting higher response rates, ≥ +1 SD of overall response rate (5 out of 8). Gemcitabine-based combination therapy showed an average response rate of 27.2% (95% CI, 22.4-32.0). Combination of gemcitabine and pegylated liposomal doxorubicin (PLD) was the most common regimen (n = 3) and was associated with possible additive effects in platinum-resistant ovarian cancer patients: response rate, gemcitabine alone 6.1%, PLD alone 19.8%, and gemcitabine with PLD 28.7% (95% CI, 20.4-37.0), respectively. TAKE HOME MESSAGE Analysis of recent clinical trials showed that gemcitabine-based combination chemotherapy was associated with the highest antitumor effects in platinum-resistant ovarian cancer patients during the study period.
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Affiliation(s)
- Koji Matsuo
- Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA, USA, Department of Gynecologic Oncology, University of Texas, Houston, TX, USA,Address correspondence to: Koji Matsuo, MD, Division of Gynecologic Oncology, Departments of Obstetrics and Gynecology, Norris Comprehensive Cancer Center, University of Southern California, 2020 Zonal Avenue, Rm522, Los Angeles, CA 90033, USA, Phone: +1-323-226-3416,
| | - Yvonne G. Lin
- Women’s Cancer Program, University of Southern California, Los Angeles, CA, USA, Department of Gynecologic Oncology, University of Texas, Houston, TX, USA
| | - Lynda D. Roman
- Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA, USA
| | - Anil K. Sood
- Department of Gynecologic Oncology, University of Texas, Houston, TX, USA, Cancer Biology, MD-Anderson Cancer Center, University of Texas, Houston, TX, USA, Center for RNA Interference and non-Coding RNA, University of Texas, Houston, TX, USA
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Kavanagh JJ, Levenback CF, Ramirez PT, Wolf JL, Moore CL, Jones MR, Meng L, Brown GL, Bast RC. Phase 2 study of canfosfamide in combination with pegylated liposomal doxorubicin in platinum and paclitaxel refractory or resistant epithelial ovarian cancer. J Hematol Oncol 2010; 3:9. [PMID: 20222977 PMCID: PMC2851575 DOI: 10.1186/1756-8722-3-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2010] [Accepted: 03/11/2010] [Indexed: 11/12/2022] Open
Abstract
Background Canfosfamide is a novel glutathione analog activated by glutathione S-transferase P1-1. This study evaluated the safety and efficacy of canfosfamide in combination with pegylated liposomal doxorubicin (PLD) in patients with platinum resistant ovarian cancer. Patients with platinum resistant ovarian carcinoma and measurable disease received canfosfamide at 960 mg/m2 in combination with PLD at 50 mg/m2, intravenously day 1 in every 28 day cycles until tumor progression or unacceptable toxicities. The primary endpoints were objective response rate (ORR) and progression-free survival (PFS). Results Canfosfamide plus PLD combination therapy was administered at 960/50 mg/m2, respectively. Thirty-nine patients received a median number of 4 cycles (range 1.0-18.0). The ORR was 27.8% (95% CI, 14.2-45.2) with a disease stabilization rate of 80.6% (95% CI, 64.0-91.8) in the evaluable population. The CA-125 marker responses correlated with the radiological findings of complete response or partial response. The median PFS was 6.0 months (95% CI, 4.2-7.9) and median survival was 17.8 months. The combination was well tolerated. Myelosuppression was managed with dose reductions and growth factor support. Grade 3 febrile neutropenia was observed in 2 patients (5.1%). Non-hematologic adverse events occurred at the expected frequency and grade for each drug alone, with no unexpected or cumulative toxicities. Conclusions Canfosfamide in combination with PLD is well tolerated and active in platinum and paclitaxel refractory or resistant ovarian cancer. A randomized phase 3 study was conducted based on this supportive phase 2 study. Trial Registration This study was registered at www.clinicaltrials.gov: NCT00052065.
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Phase 1-2a multicenter dose-ranging study of canfosfamide in combination with carboplatin and paclitaxel as first-line therapy for patients with advanced non-small cell lung cancer. J Thorac Oncol 2010; 4:1389-96. [PMID: 19701107 DOI: 10.1097/jto.0b013e3181b6b84b] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
INTRODUCTION We aimed to evaluate the safety and efficacy of canfosfamide in combination with carboplatin and paclitaxel as first-line therapy in patients with locally advanced or metastatic non-small cell lung cancer. METHODS This was a phase 1-2a, multicenter, dose-ranging trial that enrolled patients with stage IIIB or IV non-small cell lung cancer with measurable disease. Patients received canfosfamide in doses ranging from 400 to 1000 mg/m2 intravenously (IV) with carboplatin at area under the curve 6 IV and paclitaxel at 200 mg/m2 IV day 1 every 3 weeks. The primary end point was objective response rate, and the secondary endpoints were safety and progression-free survival. RESULTS One hundred twenty-nine patients were treated with canfosfamide at dose levels of 400 (n = 3), 500 (n = 51), 750 (n = 54), and 1000 mg/m2 (n = 21). Objective tumor responses by RECIST were observed in 40 patients [34% (95% confidence interval [CI], 26-44)], the median progression-free survival was 4.3 months (95% CI, 3.7-5.2) and the median survival 9.9 months (95% CI, 7.7-11.9). The percent of patients alive at 1 year was 43.1%. The overall safety profile of the combination was acceptable and consistent with the profiles of the individual agents. In an exploratory analysis, patients receiving the optional maintenance canfosfamide therapy had a prolonged median survival of 16.8 months compared with those eligible for but not receiving maintenance therapy at 8.8 months (hazard ratio = 0.38, p < 0.001). CONCLUSIONS The combination of canfosfamide with carboplatin and paclitaxel chemotherapy is well tolerated and active. Maintenance canfosfamide may further improve outcomes. This regimen is worthy of additional study.
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Phase 3 randomised study of canfosfamide (Telcyta®, TLK286) versus pegylated liposomal doxorubicin or topotecan as third-line therapy in patients with platinum-refractory or -resistant ovarian cancer. Eur J Cancer 2009; 45:2324-32. [DOI: 10.1016/j.ejca.2009.05.016] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2009] [Accepted: 05/07/2009] [Indexed: 01/29/2023]
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Abstract
Ovarian cancer is the leading cause of death from gynaecological malignancies in the Western world. Despite the evolution of surgical techniques and meticulously designed chemotherapy regimens, relapse remains almost inevitable in patients with advanced disease. In an age when great advances have been made in understanding the genetics and molecular biology of this heterogeneous disease, it is likely that the introduction of novel targeted therapies will have a major impact on the management of ovarian cancer. Importantly, such strategies might allow selection of treatments based on the molecular characteristics of tumours and bring us closer to an era of personalized medicine.
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Affiliation(s)
- Timothy A Yap
- The Royal Marsden NHS Foundation Trust, Downs Road, Sutton, Surrey, SM2 5PT, UK.
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Dinh P, Harnett P, Piccart-Gebhart MJ, Awada A. New therapies for ovarian cancer: cytotoxics and molecularly targeted agents. Crit Rev Oncol Hematol 2008; 67:103-12. [PMID: 18342536 DOI: 10.1016/j.critrevonc.2008.01.012] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2007] [Revised: 01/23/2008] [Accepted: 01/30/2008] [Indexed: 12/20/2022] Open
Abstract
Ovarian cancer, although a chemo-sensitive disease, is associated with high morbidity and mortality due to its often-late presentation. Platinums and taxanes have improved the prognosis over recent years but median overall survival is still unacceptably low (24-60 months). Apart from the manipulation of doses, schedules, mode of delivery, and combinations of existing drugs, new cytotoxics and molecularly targeted agents with different mechanisms of action must be evaluated in this patient population. This article will review the most recent clinical trials data pertaining to these new cytotoxic drugs including patupilone, telcyta, and trabectedin, as well as those of small molecules and inhibitors of the EGFR and VEGF receptor families. It will also discuss other potential signal transduction targets worthy of further evaluation in future trials.
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Affiliation(s)
- Phuong Dinh
- Institut Jules Bordet, Université Libre de Bruxelles, 1000 Brussels, Belgium.
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23
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Michael M, Doherty MM. Drug metabolism by tumours: its nature, relevance and therapeutic implications. Expert Opin Drug Metab Toxicol 2008; 3:783-803. [PMID: 18028025 DOI: 10.1517/17425255.3.6.783] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Drug-metabolising enzymes (DMEs) are present in tumours and are capable of biotransforming a variety of antineoplastics. Tumoural drug metabolism is both a potential mechanism of resistance and a means of achieving optimal therapy. This review addresses the classes of DMEs, their cytotoxic substrates and distribution in specific malignancies. The limitations of preclinical and clinical studies are highlighted. Their role in predicting therapeutic response, the activation of prodrugs and the potential for their modulation for gain is also addressed. The contribution of tumoural DMEs to cancer therapy can only be ascertained through large prospective studies and supported by new technologies. Only then can efforts be concentrated in the design of better prodrugs or combination therapy to optimise individual therapy.
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Affiliation(s)
- Michael Michael
- Peter MacCallum Cancer Centre, Division of Haematology and Medical Oncology, Locked Bag 1, A'Beckett Street, Victoria, 8006, Australia.
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Abstract
When the antitumor activity of cisplatin was discovered, no one would have thought of the existence of specific proteins able to transport Pt across the cell membrane or to specifically recognize DNA modified by this drug. However, such proteins do exist and, furthermore, are specific for the Pt substrate considered. It follows that proteins are deeply involved in managing the biological activity of cisplatin. It is expected that, after the first 20 years in which most of the efforts were devoted to understanding its mode of interaction with DNA and consequent structural and functional alterations, the role of proteins will be more deeply scavenged. How cisplatin can survive the attack of the many platinophiles present in the extracellular and intracellular media is the issue addressed in this article. Significantly, differences are observed between cisplatin, carboplatin, and oxaliplatin.
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25
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Management of Relapsed/Refractory Epithelial Ovarian Cancer: Current Standards and Novel Approaches. Taiwan J Obstet Gynecol 2007; 46:379-88. [DOI: 10.1016/s1028-4559(08)60007-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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26
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Modesitt SC, Jazaeri AA. Recurrent epithelial ovarian cancer: pharmacotherapy and novel therapeutics. Expert Opin Pharmacother 2007; 8:2293-305. [PMID: 17927484 DOI: 10.1517/14656566.8.14.2293] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Epithelial ovarian cancer will strike between 1 - 2% of women in developed countries and, unfortunately, it largely remains a lethal disease due to late-stage at diagnosis and the eventual development of chemotherapy resistance. Ovarian cancer is initially treated with surgical resection and chemotherapy (primarily platinum/taxane combinations) and remission can be attained for the majority of patients. Despite this, most women will recur and require multiple further therapies. The purpose of this paper is to review the existing treatment options, including surgery, traditional chemotherapy as well as upcoming novel and targeted therapies that may one day improve outcomes in this disease.
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Affiliation(s)
- Susan C Modesitt
- University of Virginia Health Center, Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, Box 800712, Charlottesville, VA 22932, USA.
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27
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Lo HW, Ali-Osman F. Genetic polymorphism and function of glutathione S-transferases in tumor drug resistance. Curr Opin Pharmacol 2007; 7:367-74. [PMID: 17681492 DOI: 10.1016/j.coph.2007.06.009] [Citation(s) in RCA: 154] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2007] [Accepted: 06/28/2007] [Indexed: 01/02/2023]
Abstract
The human glutathione S-transferase, GSTs, possess both enzymatic and non-enzymatic functions and are involved in many important cellular processes, such as, phase II metabolism, stress response, cell proliferation, apoptosis, oncogenesis, tumor progression and drug resistance. The non-enzymatic functions of GSTs involve their interactions with cellular proteins, such as, JNK, TRAF, ASK, PKC, and TGM2, during which, either the interacting protein partner undergoes functional alteration or the GST protein itself is post-translationally modified and/or functionally altered. The majority of GST genes harbor polymorphisms that influence their transcription and/or function of their encoded proteins. This overview focuses on recent insights into the biology and pharmacogenetics of GSTs as a determinant of cancer drug resistance and response of cancer patients to therapy.
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Affiliation(s)
- Hui-Wen Lo
- Department of Surgery, The Comprehensive Cancer Center and The Preston Robert Tisch Brain Tumor Center, Duke University, Durham, NC 27707, United States
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28
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Eklund BI, Mannervik B. Importance of a hypervariable active-site residue in human Mu class glutathione transferases catalyzing the bioactivation of chemotherapeutic thiopurine prodrugs. Biochim Biophys Acta Gen Subj 2007; 1770:1098-103. [PMID: 17493759 DOI: 10.1016/j.bbagen.2007.04.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2006] [Revised: 03/30/2007] [Accepted: 04/02/2007] [Indexed: 10/23/2022]
Abstract
Glutathione transferases (GSTs) catalyze the bioactivation of the thiopurine prodrugs azathioprine, cis-6-(2-acetylvinylthio)purine (cAVTP) and trans-6-(2-acetylvinylthio)guanine (tAVTG), thereby releasing the antimetabolites 6-mercaptopurine and 6-thioguanine. In the GST Mu class, GST M1-1 has the highest catalytic efficiency, whereas GST M2-2 and other enzymes are less active. In the evolution of Mu class GSTs, residue 210 appears hypervariable and has particular functional significance. We demonstrate that the catalytic activity of GST M1-1 with cAVTP or tAVTG is successively diminished when wild-type Ser-210 is mutated into Ala followed by Thr. Conversely, mutating wild-type Thr-210 in GST M2-2 into Ala and Ser enhanced the corresponding activities. Comparisons were also made with GST M2-2 distinguished by Gly or Pro in position 210, as well as wild-type GSTs M4-4 and M5-5. The results suggest that the hydroxyl group of Ser in position 210 stabilizes the transition state of the GST-catalyzed reaction. The low activity of GSTs containing Thr in position 210 is probably due to steric hindrance caused by the beta-methyl group of the side chain. The ratios of the different catalytic efficiencies were translated into differences in the Gibbs free energies of transition state stabilization. The effects of the mutations were qualitatively parallel for the alternative substrates, but vary significantly in magnitude. From the evolutionary perspective the data show that a point mutation can alternatively enhance or attenuate the activity with a particular substrate and illustrate the functional plasticity of GSTs.
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Affiliation(s)
- Birgitta I Eklund
- Department of Biochemistry and Organic Chemistry, Uppsala University, Biomedical Center, Box 576, SE-75123 Uppsala, Sweden
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29
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Tew KD. Redox in redux: Emergent roles for glutathione S-transferase P (GSTP) in regulation of cell signaling and S-glutathionylation. Biochem Pharmacol 2007; 73:1257-69. [PMID: 17098212 DOI: 10.1016/j.bcp.2006.09.027] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2006] [Revised: 09/27/2006] [Accepted: 09/28/2006] [Indexed: 01/04/2023]
Abstract
Glutathione (GSH) provides a major source of thiol homeostasis critical to the maintenance of a reduced cellular environment that is conducive to cell survival. Mammals have accumulated a significant cadre of sulfur containing proteins, the interactive significance of which has become clear in recent times. Glutathione transferases (GST) are prevalent in eukaryotes and have been ascribed catalytic functions that involve detoxification of electrophiles through thioether bond formation with the cysteine thiol of GSH. The neutralizing impact of these reactions on products of reactive oxygen has contributed to the significant evolutionary conservation and adaptive functional redundancy of the multifaceted GSH system. Amongst the GSTs, GSTP has been implicated in tumorigenesis and in anticancer drug resistance. Emerging studies indicate that GSTP has ligand binding properties and contributes in the regulation of signaling kinases through direct protein:protein interactions. Furthermore, S-glutathionylation is a post-translational modification of low pK(a) cysteine residues in target proteins. The forward rate of the S-glutathionylation reaction can be influenced by GSTP, whereas the reverse rate is affected by a number of redox sensitive proteins including glutaredoxin, thioredoxin and sulfiredoxin. The functional importance of these reactions in governing how cells respond to oxidative or nitrosative stress exemplifies the broad importance of GSH/GST homeostasis in conditions such as cancer, ageing and neurodegenerative diseases. GSTP has also provided a platform for therapeutic drug development where some agents have completed preclinical testing and are in clinical trial for the management of cancer.
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Affiliation(s)
- Kenneth D Tew
- Department of Cell and Molecular Pharmacology and Experimental Therapeutics, Medical University of South Carolina, 173 Ashley Avenue, P.O. Box 250505, Charleston, SC 29425, United States.
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Lorusso D, Ferrandina G, Fanfani F, Gagliardi ML, Scambia G. Investigational agents against platinum-resistant ovarian cancer. Expert Opin Investig Drugs 2007; 16:325-36. [PMID: 17302527 DOI: 10.1517/13543784.16.3.325] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Ovarian cancer is still the fourth cause of death by cancer among women and is the most fatal among gynaecological tumours. The goal of treatment for patients with recurrent, platinum-resistant (platinum-free interval < 6 months) ovarian cancer is the palliation of symptoms because no evidence indicates that present therapies may prolong survival in this setting of patients. Successful management of these patients depends on the identification of agents that are not cross-resistant with platinum compounds. The development of molecular biology is providing us with new information on the molecular basis of cancer, its mechanism of initiation and progression, and supply the need of a more patient-tailored therapy where specific tumours are treated with specific drugs. This paper reports and discusses new developments in the treatment of platinum-resistant ovarian cancer patients. The authors present proteomic advances, including the HER kinases, the 26S proteasome and the angiogenesis pathway. The opportunities to change the treatment of ovarian cancer will require creative clinical trial design but the next 10 years promise to be filled with therapeutic advances for patients with ovarian cancer.
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Affiliation(s)
- Domenica Lorusso
- Catholic University of the Sacred Heart, Gynecologic Oncology Unit, Largo A Gemelli, 8 00168 Rome, Italy
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Abstract
Over the past several years, clinical research efforts in ovarian cancer employing a number of U.S. Food and Drug Administration (FDA)-approved antineoplastic agents have permitted the development of approaches that both improve the effectiveness and decrease the toxicities of systemic therapy of ovarian cancer. These initiatives, including prospective trials and retrospective examinations of large clinical experience, have involved agents previously approved by the FDA for use in ovarian cancer (e.g., cisplatin, paclitaxel, topotecan, and liposomal doxorubicin) and the development of new strategies for drugs approved for other malignant conditions (e.g., gemcitabine, docetaxel, etoposide, irinotecan, vinorelbine, and bevacizumab). It can be anticipated that future studies involving novel approved agents will further expand the oncologist's weapons against ovarian cancer.
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Affiliation(s)
- Maurie Markman
- Department of Gynecologic Medical Oncology, University of Texas M.D. Anderson Cancer Center (Mail Box 121), 1515 Holcombe Boulevard, Houston, Texas 77030, USA.
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Abstract
Current systemic therapy for ovarian cancer consists of a combination of carboplatin and paclitaxel. While the majority of patients achieve clinical complete remission after six cycles of chemotherapy, the relapse rate stands at over 50%. Median survival time for patients after recurrence is approximately 2 years. New treatment approaches for patients with advanced ovarian cancer include consolidation and maintenance therapy, intraperitoneal administration of cytotoxic agents, new combination chemotherapy regimens, the development of new cytotoxic agents, and molecular-targeted therapies. These agents will be evaluated either singularly or with chemotherapy. Currently, the Gynecologic Oncology Group is evaluating a combination of bevacizumab together with paclitaxel and carboplatin in previously untreated patients with advanced ovarian cancer. This trial is based on phase II data that suggest that bevacizumab as a single agent has significant activity in patients with recurrent ovarian cancer. In addition, the Gynecologic Oncology Group will be conducting phase II trials of different combinations of intraperitoneal chemotherapy in an effort to decrease toxicity associated with current intraperitoneal regimens that have shown an improvement in survival in patients with small-volume stage III disease. The Gynecologic Oncology Group will also be conducting a trial of maintenance therapy in patients who enter clinical complete remission with paclitaxel plus carboplatin, comparing observation with monthly paclitaxel or monthly paclitaxel poliglumex. Novel new cytotoxic and biologic agents are also being evaluated as single agents in phase II trials in patients with recurrent ovarian cancer.
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Abstract
Telik, Inc. (Palo Alto, CA, USA) is currently developing TLK-286, a novel prodrug that is preferentially activated by glutathione S-transferase P1-1 (GST-pi). TLK-286 is the lead clinical candidate from a group of rationally designed glutathione analogues designed to exploit high GST-pi levels in solid tumours and drug-resistant cell populations. This concept was based on extensive literature showing that the overexpression of GST-pi in human tumours is associated with malignancy, poor prognosis and the development of drug resistance. Thus, the selective targeting of susceptible tumour phenotypes is a strategy that should result in the release of more active drug in malignant cells compared with normal tissue, thereby achieving an improved therapeutic index. A number of published preclinical studies have confirmed the mechanism of action of this drug. In a series of Phase II clinical trials, TLK-286 was initially shown to have clinical activity and a favorable toxicity profile as a single agent in the salvage setting in ovarian, non-small cell lung, breast and colorectal cancers. Recently, Phase II trials have been reported that demonstrated TLK-286 is active and did not increase the toxicity in combination treatment regimens with standard chemotherapeutic agents, including platinums, taxanes and anthracyclines in previously treated patients with ovarian and non-small cell lung cancers, and in the first-line treatment setting in non-small cell lung cancer patients. TLK-286 is also presently under active testing in Phase III settings for non-small cell lung and ovarian cancers.
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Affiliation(s)
- Kenneth D Tew
- Department of Cell and Molecular Pharmacology and Experimental Therapeutics, Medical University of South Carolina, 173 Ashley Avenue, PO Box 250505, Charleston, SC 29425, USA.
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