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Cao Y, Zhou X, Nie Q, Zhang J. Inhibition of the thioredoxin system for radiosensitization therapy of cancer. Eur J Med Chem 2024; 268:116218. [PMID: 38387331 DOI: 10.1016/j.ejmech.2024.116218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Revised: 01/28/2024] [Accepted: 02/04/2024] [Indexed: 02/24/2024]
Abstract
Radiotherapy (RT) stands as a cornerstone in the clinical armamentarium against various cancers due to its proven efficacy. However, the intrinsic radiation resistance exhibited by cancer cells, coupled with the adverse effects of RT on normal tissues, often compromises its therapeutic potential and leads to unwanted side effects. This comprehensive review aims to consolidate our understanding of how radiosensitizers inhibit the thioredoxin (Trx) system in cellular contexts. Notable radiosensitizers, including gold nanoparticles (GNPs), gold triethylphosphine cyanide ([Au(SCN) (PEt3)]), auranofin, ceria nanoparticles (CONPs), curcumin and its derivatives, piperlongamide, indolequinone derivatives, micheliolide, motexafin gadolinium, and ethane selenide selenidazole derivatives (SeDs), are meticulously elucidated in terms of their applications in radiotherapy. In this review, the sensitization mechanisms and the current research progress of these radiosensitizers are discussed in detail, with the overall aim of providing valuable insights for the judicious application of Trx system inhibitors in the field of cancer radiosensitization therapy.
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Affiliation(s)
- Yisheng Cao
- School of Pharmacy, State Key Laboratory of Applied Organic Chemistry, and College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, China
| | - Xiedong Zhou
- School of Pharmacy, State Key Laboratory of Applied Organic Chemistry, and College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, China
| | - Qiuying Nie
- School of Pharmacy, State Key Laboratory of Applied Organic Chemistry, and College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, China
| | - Junmin Zhang
- School of Pharmacy, State Key Laboratory of Applied Organic Chemistry, and College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, China.
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2
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Ma X, Liang X, Yao M, Gao Y, Luo Q, Li X, Yu Y, Sun Y, Cheng MHY, Chen J, Zheng G, Shi J, Wang F. Myoglobin-loaded gadolinium nanotexaphyrins for oxygen synergy and imaging-guided radiosensitization therapy. Nat Commun 2023; 14:6187. [PMID: 37794000 PMCID: PMC10550994 DOI: 10.1038/s41467-023-41782-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Accepted: 09/12/2023] [Indexed: 10/06/2023] Open
Abstract
Gadolinium (Gd3+)-coordinated texaphyrin (Gd-Tex) is a promising radiosensitizer that entered clinical trials, but temporarily fails largely due to insufficient radiosensitization efficacy. Little attention has been given to using nanovesicles to improve its efficacy. Herein, Gd-Tex is transformed into building blocks "Gd-Tex-lipids" to self-assemble nanovesicles called Gd-nanotexaphyrins (Gd-NTs), realizing high density packing of Gd-Tex in a single nanovesicle and achieving high Gd-Tex accumulation in tumors. To elucidate the impact of O2 concentration on Gd-Tex radiosensitization, myoglobin (Mb) is loaded into Gd-NTs (Mb@Gd-NTs), resulting in efficient relief of tumor hypoxia and significant enhancement of Gd-Tex radiosensitization, eventually inducing the obvious long-term antitumor immune memory to inhibit tumor recurrence. In addition to Gd3+, the versatile Mb@Gd-NTs can also chelate 177Lu3+ (Mb@177Lu/Gd-NTs), enabling SPECT/MRI dual-modality imaging for accurately monitoring drug delivery in real-time. This "one-for-all" nanoplatform with the capability of chelating various trivalent metal ions exhibits broad clinical application prospects in imaging-guided radiosensitization therapy.
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Affiliation(s)
- Xiaotu Ma
- Key Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, 100101, Beijing, P. R. China
- Department of Ultrasound, Peking University Third Hospital, 100191, Beijing, P. R. China
| | - Xiaolong Liang
- Department of Ultrasound, Peking University Third Hospital, 100191, Beijing, P. R. China
| | - Meinan Yao
- Medical Isotopes Research Center and Department of Radiation Medicine, State Key Laboratory of Natural and Biomimetic Drugs, School of Basic Medical Sciences, International Cancer Institute, Peking University, 100191, Beijing, P. R. China
| | - Yu Gao
- Key Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, 100101, Beijing, P. R. China
| | - Qi Luo
- Guangzhou National Laboratory, 510005, Guangzhou, P.R. China
| | - Xiaoda Li
- Medical and Health Analysis Center, Peking University, 100191, Beijing, P. R. China
| | - Yue Yu
- Key Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, 100101, Beijing, P. R. China
| | - Yining Sun
- Key Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, 100101, Beijing, P. R. China
| | - Miffy H Y Cheng
- Princess Margaret Cancer Centre, University Health Network, Tronto, ON, M5G 1L7, Canada
| | - Juan Chen
- Princess Margaret Cancer Centre, University Health Network, Tronto, ON, M5G 1L7, Canada
| | - Gang Zheng
- Princess Margaret Cancer Centre, University Health Network, Tronto, ON, M5G 1L7, Canada.
- Department of Medical Biophysics, University of Toronto, Tronto, ON, M5G 1L7, Canada.
| | - Jiyun Shi
- Key Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, 100101, Beijing, P. R. China.
| | - Fan Wang
- Key Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, 100101, Beijing, P. R. China.
- Medical Isotopes Research Center and Department of Radiation Medicine, State Key Laboratory of Natural and Biomimetic Drugs, School of Basic Medical Sciences, International Cancer Institute, Peking University, 100191, Beijing, P. R. China.
- Guangzhou National Laboratory, 510005, Guangzhou, P.R. China.
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3
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Gencheva R, Cheng Q, Arnér ESJ. Thioredoxin reductase selenoproteins from different organisms as potential drug targets for treatment of human diseases. Free Radic Biol Med 2022; 190:320-338. [PMID: 35987423 DOI: 10.1016/j.freeradbiomed.2022.07.020] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 06/25/2022] [Accepted: 07/26/2022] [Indexed: 11/15/2022]
Abstract
Human thioredoxin reductase (TrxR) is a selenoprotein with a central role in cellular redox homeostasis, utilizing a highly reactive and solvent-exposed selenocysteine (Sec) residue in its active site. Pharmacological modulation of TrxR can be obtained with several classes of small compounds showing different mechanisms of action, but most often dependent upon interactions with its Sec residue. The clinical implications of TrxR modulation as mediated by small compounds have been studied in diverse diseases, from rheumatoid arthritis and ischemia to cancer and parasitic infections. The possible involvement of TrxR in these diseases was in some cases serendipitously discovered, by finding that existing clinically used drugs are also TrxR inhibitors. Inhibiting isoforms of human TrxR is, however, not the only strategy for human disease treatment, as some pathogenic parasites also depend upon Sec-containing TrxR variants, including S. mansoni, B. malayi or O. volvulus. Inhibiting parasite TrxR has been shown to selectively kill parasites and can thus become a promising treatment strategy, especially in the context of quickly emerging resistance towards other drugs. Here we have summarized the basis for the targeting of selenoprotein TrxR variants with small molecules for therapeutic purposes in different human disease contexts. We discuss how Sec engagement appears to be an indispensable part of treatment efficacy and how some therapeutically promising compounds have been evaluated in preclinical or clinical studies. Several research questions remain before a wider application of selenoprotein TrxR inhibition as a first-line treatment strategy might be developed. These include further mechanistic studies of downstream effects that may mediate treatment efficacy, identification of isoform-specific enzyme inhibition patterns for some given therapeutic compounds, and the further elucidation of cell-specific effects in disease contexts such as in the tumor microenvironment or in host-parasite interactions, and which of these effects may be dependent upon the specific targeting of Sec in distinct TrxR isoforms.
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Affiliation(s)
- Radosveta Gencheva
- Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, 17177, Sweden
| | - Qing Cheng
- Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, 17177, Sweden
| | - Elias S J Arnér
- Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, 17177, Sweden; Department of Selenoprotein Research, National Tumor Biology Laboratory, National Institute of Oncology, 1122, Budapest, Hungary.
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4
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Jin GQ, Chau CV, Arambula JF, Gao S, Sessler JL, Zhang JL. Lanthanide porphyrinoids as molecular theranostics. Chem Soc Rev 2022; 51:6177-6209. [PMID: 35792133 DOI: 10.1039/d2cs00275b] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
In recent years, lanthanide (Ln) porphyrinoids have received increasing attention as theranostics. Broadly speaking, the term 'theranostics' refers to agents designed to allow both disease diagnosis and therapeutic intervention. This Review summarises the history and the 'state-of-the-art' development of Ln porphyrinoids as theranostic agents. The emphasis is on the progress made within the past decade. Applications of Ln porphyrinoids in near-infrared (NIR, 650-1700 nm) fluorescence imaging (FL), magnetic resonance imaging (MRI), radiotherapy, and chemotherapy will be discussed. The use of Ln porphyrinoids as photo-activated agents ('phototheranostics') will also be highlighted in the context of three promising strategies for regulation of porphyrinic triplet energy dissipation pathways, namely: regioisomeric effects, metal regulation, and the use of expanded porphyrinoids. The goal of this Review is to showcase some of the ongoing efforts being made to optimise Ln porphyrinoids as theranostics and as phototheranostics, in order to provide a platform for understanding likely future developments in the area, including those associated with structure-based innovations, functional improvements, and emerging biological activation strategies.
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Affiliation(s)
- Guo-Qing Jin
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, P. R. China.
| | - Calvin V Chau
- Department of Chemistry, The University of Texas at Austin, Austin, Texas 78712-1224, USA.
| | - Jonathan F Arambula
- Department of Chemistry, The University of Texas at Austin, Austin, Texas 78712-1224, USA. .,InnovoTEX, Inc. 3800 N. Lamar Blvd, Austin, Texas 78756, USA.
| | - Song Gao
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, P. R. China. .,Chemistry and Chemical Engineering Guangdong Laboratory, Shantou 515031, P. R. China.,Guangdong-Hong Kong-Macao Joint Laboratory of Optoelectronic and Magnetic Functional Materials, Spin-X Institute, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510641, P. R. China
| | - Jonathan L Sessler
- Department of Chemistry, The University of Texas at Austin, Austin, Texas 78712-1224, USA.
| | - Jun-Long Zhang
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, P. R. China. .,Chemistry and Chemical Engineering Guangdong Laboratory, Shantou 515031, P. R. China
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5
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Schubert K, Schwob L, Dörner S, Girod M, MacAleese L, Pieterse CL, Schlathölter T, Techert S, Bari S. Ionization and Photofragmentation of Isolated Metalloporphyrin Cations Investigated by VUV Action Spectroscopy*. Chemistry 2021; 27:12371-12379. [PMID: 34137472 PMCID: PMC8457234 DOI: 10.1002/chem.202101515] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Indexed: 11/13/2022]
Abstract
We investigated the photoionization and fragmentation of isolated metal protoporphyrin IX cations (MPPIX+ with M=Fe, Co, Zn) by means of vacuum-ultraviolet (VUV) action spectroscopy in the energy range of 8.5-35 eV. Experiments were carried out in the gas phase by interfacing an electrospray ionization tandem mass spectrometer with a synchrotron beamline. The mass spectra and partial ion yields show that photoexcitation of the precursor ions predominantly leads to . CH2 COOH radical side-chain losses of the macrocycle with additional methyl radical (. CH3 ) side-chain losses. Ionization, in contrast, leads to the formation of the intact ionized precursor and various doubly charged fragments which are mostly due to side-chain cleavages. Although statistical fragmentation dominates, we found evidence for non-statistical processes such as new fragments involving for example single and double H2 O losses, indicating that different relaxation mechanisms are at play upon photoionization compared to photoexcitation. The measured ionization energies were 9.6±0.2 eV, 9.4±0.2 eV and 9.6±0.2 eV for FePPIX+ , CoPPIX+ and ZnPPIX+ , respectively.
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Affiliation(s)
- Kaja Schubert
- Deutsches Elektronen-Synchrotron DESYNotkestr. 8522607HamburgGermany
| | - Lucas Schwob
- Deutsches Elektronen-Synchrotron DESYNotkestr. 8522607HamburgGermany
| | - Simon Dörner
- Deutsches Elektronen-Synchrotron DESYNotkestr. 8522607HamburgGermany
| | - Marion Girod
- Univ LyonUniversité Claude Bernard Lyon 1CNRS UMR 5280Institut des Sciences Analytiques5 rue de la Doua69100VilleurbanneFrance
| | - Luke MacAleese
- Univ LyonUniversité Claude Bernard Lyon 1CNRS UMR 5306Institut Lumière Matière69622LyonFrance
| | | | - Thomas Schlathölter
- Zernike Institute for Advanced MaterialsUniversity of GroningenNijenborgh 49747 AGGroningenThe Netherlands
| | - Simone Techert
- Deutsches Elektronen-Synchrotron DESYNotkestr. 8522607HamburgGermany
- Institut für RöntgenphysikGeorg-August-Universität GöttingenFriedrich-Hund-Platz 137077GöttingenGermany
| | - Sadia Bari
- Deutsches Elektronen-Synchrotron DESYNotkestr. 8522607HamburgGermany
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Allegra AG, Mannino F, Innao V, Musolino C, Allegra A. Radioprotective Agents and Enhancers Factors. Preventive and Therapeutic Strategies for Oxidative Induced Radiotherapy Damages in Hematological Malignancies. Antioxidants (Basel) 2020; 9:antiox9111116. [PMID: 33198328 PMCID: PMC7696711 DOI: 10.3390/antiox9111116] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Revised: 11/08/2020] [Accepted: 11/10/2020] [Indexed: 12/13/2022] Open
Abstract
Radiation therapy plays a critical role in the management of a wide range of hematologic malignancies. It is well known that the post-irradiation damages both in the bone marrow and in other organs are the main causes of post-irradiation morbidity and mortality. Tumor control without producing extensive damage to the surrounding normal cells, through the use of radioprotectors, is of special clinical relevance in radiotherapy. An increasing amount of data is helping to clarify the role of oxidative stress in toxicity and therapy response. Radioprotective agents are substances that moderate the oxidative effects of radiation on healthy normal tissues while preserving the sensitivity to radiation damage in tumor cells. As well as the substances capable of carrying out a protective action against the oxidative damage caused by radiotherapy, other substances have been identified as possible enhancers of the radiotherapy and cytotoxic activity via an oxidative effect. The purpose of this review was to examine the data in the literature on the possible use of old and new substances to increase the efficacy of radiation treatment in hematological diseases and to reduce the harmful effects of the treatment.
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Affiliation(s)
- Andrea Gaetano Allegra
- Radiation Oncology Unit, Department of Biomedical, Experimental, and Clinical Sciences “Mario Serio”, Azienda Ospedaliero-Universitaria Careggi, University of Florence, 50100 Florence, Italy;
| | - Federica Mannino
- Department of Clinical and Experimental Medicine, University of Messina, c/o AOU Policlinico G. Martino, Via C. Valeria Gazzi, 98125 Messina, Italy;
| | - Vanessa Innao
- Department of Human Pathology in Adulthood and Childhood “Gaetano Barresi”, Division of Haematology, University of Messina, 98125 Messina, Italy; (V.I.); (C.M.)
| | - Caterina Musolino
- Department of Human Pathology in Adulthood and Childhood “Gaetano Barresi”, Division of Haematology, University of Messina, 98125 Messina, Italy; (V.I.); (C.M.)
| | - Alessandro Allegra
- Department of Human Pathology in Adulthood and Childhood “Gaetano Barresi”, Division of Haematology, University of Messina, 98125 Messina, Italy; (V.I.); (C.M.)
- Correspondence: ; Tel.: +39-090-221-2364
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7
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Chemistry, structure, and biological roles of Au-NHC complexes as TrxR inhibitors. Bioorg Chem 2020; 95:103552. [DOI: 10.1016/j.bioorg.2019.103552] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Revised: 11/23/2019] [Accepted: 12/23/2019] [Indexed: 12/12/2022]
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8
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Cao X, Wu L, Zhang J, Dolg M. Density Functional Studies of Coenzyme NADPH and Its Oxidized Form NADP + : Structures, UV-Vis Spectra, and the Oxidation Mechanism of NADPH. J Comput Chem 2019; 41:305-316. [PMID: 31713255 DOI: 10.1002/jcc.26103] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Revised: 10/03/2019] [Accepted: 10/16/2019] [Indexed: 12/31/2022]
Abstract
Density functional theory has been used to study the biologically important coenzyme NADPH and its oxidized form NADP+ . It was found that free NADPH prefers a compact structure in gas phase and exists in more extended geometries in aqueous solution. Ultraviolet-visible absorption spectra in aqueous solution were calculated for NADPH with an explicit treatment of 100 surrounding water molecules in combination with the COSMO solvation model for bulk hydration effects. The obtained spectra using the B3LYP hybrid density functional agree quite well with experimental data. The changes of Gibbs free energies ΔG in reactions of NADPH with O2 observed experimentally in cardiovascular and in chemical systems, that is, NADPH + 2 3 O2 → NADP+ + 2 O2 - + H+ and NADPH + 1 O2 + H+ → NADP+ + H2 O2 , respectively, were calculated. The NADPH oxidation reaction in the cardiovascular system cannot proceed without activation since the obtained ΔG is positive. The reaction of NADPH in the chemical system with singlet oxygen was found to proceed in two ways, each consisting of two steps, that is, NADPH firstly reacts with 1 O2 barrierlessly to form NADP+ and HO2 - , from which H2 O2 is formed in a spontaneous reaction with H+ , or 1 O2 and H+ initially form 1 HO2 + , which further reacts with NADPH to yield NADP+ and H2 O2 . © 2019 The Authors. Journal of Computational Chemistry published by Wiley Periodicals, Inc.
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Affiliation(s)
- Xiaoyan Cao
- Institute for Theoretical Chemistry, University of Cologne, Greinstr. 4, D-50939, Cologne, Germany
| | - Liangliang Wu
- Institute for Theoretical Chemistry, University of Cologne, Greinstr. 4, D-50939, Cologne, Germany.,Key Laboratory of Theoretical and Computational Photochemistry of Ministry of Education, Department of Chemistry, Beijing Normal University, Xin-wai-da-jie No. 19, Beijing, 10087, China
| | - Jun Zhang
- Department of Chemistry, University of Illinois at Urbana Champaign, Urbana, Illinois, 61801-3364
| | - Michael Dolg
- Institute for Theoretical Chemistry, University of Cologne, Greinstr. 4, D-50939, Cologne, Germany
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9
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Eskian M, Khorasanizadeh M, Zinzani PL, Illidge TM, Rezaei N. Novel Methods to Improve the Efficiency of Radioimmunotherapy for Non-Hodgkin Lymphoma. Int Rev Immunol 2019; 38:79-91. [PMID: 30931651 DOI: 10.1080/08830185.2019.1588266] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Radioimmunotherapy (RIT) is a novel strategy for treating non-Hodgkin lymphoma (NHL). Several studies have shown the promising results of using RIT in NHL, which have led to FDA approval for two RIT agents in treating low grade NHL. In spite of these favorable results in low-grade NHL, most of the aggressive or relapsed/refractory NHL subjects experience relapses following RIT. Although more aggressive treatments such as myeloablative doses of RIT followed by stem cell transplantation appear to be able to provide a longer survival for some patients these approaches are associated with significant treatment-related adverse events and challenging to deliver in most centers. Therefore, it seems reasonable to develop treatment approaches that enhance the efficiency of RIT, while reducing its toxicity. In this paper, novel methods that improve the efficiency of RIT and reduce its toxicity through various mechanisms are reviewed. Further clinical development of these methods could expand the NHL patient groups eligible for receiving RIT, and even extend the use of RIT to new indications and disease groups in future.
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Affiliation(s)
- Mahsa Eskian
- a Research Center for Immunodeficiencies, Children's Medical Center, Tehran University of Medical Sciences , Tehran , Iran.,b Network of Immunity in Infection, Malignancy and Autoimmunity (NIIMA), Universal Scientific Education and Research Network (USERN) , Tehran , Iran
| | - MirHojjat Khorasanizadeh
- a Research Center for Immunodeficiencies, Children's Medical Center, Tehran University of Medical Sciences , Tehran , Iran.,b Network of Immunity in Infection, Malignancy and Autoimmunity (NIIMA), Universal Scientific Education and Research Network (USERN) , Tehran , Iran
| | - Pier Luigi Zinzani
- c Institute of Hematology "L. e A. Seràgnoli", University of Bologna , Bologna , Italy
| | - Tim M Illidge
- d Manchester Academic Health Sciences Centre, University of Manchester, Christie NHS Foundation Trust , Manchester , UK
| | - Nima Rezaei
- a Research Center for Immunodeficiencies, Children's Medical Center, Tehran University of Medical Sciences , Tehran , Iran.,e Department of Immunology, School of Medicine , Tehran University of Medical Sciences , Tehran , Iran.,f Cancer Immunology Project (CIP), Universal Scientific Education and Research Network (USERN) , Tehran , Iran
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Abstract
Combining metallo-drugs with ionising radiation for synergistic cancer cell killing: chemical design principles, mechanisms of action and emerging applications.
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Affiliation(s)
- Martin R. Gill
- CRUK/MRC Oxford Institute for Radiation Oncology
- Department of Oncology
- University of Oxford
- Oxford
- UK
| | - Katherine A. Vallis
- CRUK/MRC Oxford Institute for Radiation Oncology
- Department of Oncology
- University of Oxford
- Oxford
- UK
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11
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Abstract
SIGNIFICANCE There are a number of redox-active anticancer agents currently in development based on the premise that altered redox homeostasis is necessary for cancer cell's survival. Recent Advances: This review focuses on the relatively few agents that target cellular redox homeostasis to have entered clinical trial as anticancer drugs. CRITICAL ISSUES The success rate of redox anticancer drugs has been disappointing compared to other classes of anticancer agents. This is due, in part, to our incomplete understanding of the functions of the redox targets in normal and cancer tissues, leading to off-target toxicities and low therapeutic indexes of the drugs. The field also lags behind in the use biomarkers and other means to select patients who are most likely to respond to redox-targeted therapy. FUTURE DIRECTIONS If we wish to derive clinical benefit from agents that attack redox targets, then the future will require a more sophisticated understanding of the role of redox targets in cancer and the increased application of personalized medicine principles for their use. Antioxid. Redox Signal. 26, 262-273.
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Affiliation(s)
| | - Garth Powis
- 2 Sanford Burnham Prebys Medical Discovery Institute Cancer Center , La Jolla, California
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12
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Myrissa A, Braeuer S, Martinelli E, Willumeit-Römer R, Goessler W, Weinberg AM. Gadolinium accumulation in organs of Sprague-Dawley® rats after implantation of a biodegradable magnesium-gadolinium alloy. Acta Biomater 2017; 48:521-529. [PMID: 27845277 DOI: 10.1016/j.actbio.2016.11.024] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Revised: 09/28/2016] [Accepted: 11/10/2016] [Indexed: 12/23/2022]
Abstract
Biodegradable magnesium implants are under investigation because of their promising properties as medical devices. For enhancing the mechanical properties and the degradation resistance, rare earth elements are often used as alloying elements. In this study Mg10Gd pins were implanted into Sprague-Dawley® rats. The pin volume loss and a possible accumulation of magnesium and gadolinium in the rats' organs and blood were investigated in a long-term study over 36weeks. The results showed that Mg10Gd is a fast disintegrating material. Already 12weeks after implantation the alloy is fragmented to smaller particles, which can be found within the intramedullary cavity and the cortical bones. They disturbed the bone remodeling until the end of the study. The results concerning the elements' distribution in the animals' bodies were even more striking, since an accumulation of gadolinium could be observed in the investigated organs over the whole time span. The most affected tissue was the spleen, with up to 3240μgGd/kg wet mass, followed by the lung, liver and kidney (up to 1040, 685 and 207μgGd/kg). In the brain, muscle and heart, the gadolinium concentrations were much smaller (less than 20μg/kg), but an accumulation could still be detected. Interestingly, blood serum samples showed no accumulation of magnesium and gadolinium. This is the first time that an accumulation of gadolinium in animal organs was observed after the application of a gadolinium-containing degradable magnesium implant. These findings demonstrate the importance of future investigations concerning the distribution of the constituents of new biodegradable materials in the body, to ensure the patients' safety. STATEMENT OF SIGNIFICANCE In the last years, biodegradable Mg alloys are under investigation due to their promising properties as orthopaedic devices used for bone fracture stabilization. Gadolinium as Rare Earth Element enhances the mechanical properties of Mg-Gd alloys but its toxicity in humans is still questionable. Up to now, there is no study investigating the elements' metabolism of a REE-containing Magnesium alloy in an animal model. In this study, we examined the gadolinium distribution and accumulation in rat organs during the degradation of Mg10Gd. Our findings showed that Gd is accumulating in the animal organs, especially in spleen, liver and kidney. This study is of crucial benefit regarding a safe application of REE-containing Magnesium alloys in humans.
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13
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Cao X, Heinz N, Zhang J, Dolg M. The first water coordination sphere of lanthanide(iii) motexafins (Ln-Motex2+, Ln = La, Gd, Lu) and its effects on structures, reduction potentials and UV-vis absorption spectra. Theoretical studies. Phys Chem Chem Phys 2017; 19:20160-20171. [DOI: 10.1039/c7cp02861j] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
An explicit treatment of strongly bound water molecules is mandatory to calculate correct UV-vis absorption spectra of lanthanide(iii) motexafins.
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Affiliation(s)
- Xiaoyan Cao
- Institute for Theoretical Chemistry, University of Cologne
- D-50939 Cologne
- Germany
| | - Norah Heinz
- Institute for Theoretical Chemistry, University of Cologne
- D-50939 Cologne
- Germany
| | - Jun Zhang
- Department of Chemistry
- University of Illinois at Urbana Champaign
- Urbana
- USA
| | - Michael Dolg
- Institute for Theoretical Chemistry, University of Cologne
- D-50939 Cologne
- Germany
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Sethi S, Das PK, Behera N. The chemistry of aminoferrocene, Fe{(η5-C5H4NH2)(η5-Cp)}: Synthesis, reactivity and applications. J Organomet Chem 2016. [DOI: 10.1016/j.jorganchem.2016.10.014] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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15
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Biersack B, Schobert R. Current State of Metal-Based Drugs for the Efficient Therapy of Lung Cancers and Lung Metastases. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 893:211-224. [PMID: 26667346 DOI: 10.1007/978-3-319-24223-1_11] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Lung cancer is the second most common cancer in both men and women and thus a leading cause of cancer-related deaths worldwide. New efficient treatments especially for its advanced stages and metastases are desperately needed, particularly with regard to overcoming the resistance which thwarts the efficacy of most clinically established drugs such as the platinum complexes. Glimpses of hope are new metal-based drugs that have emerged over the past decade which displayed efficacy in patients with platinum-resistant tumors and metastases. This chapter provides an overview of the latest developments of such metal-based drugs against lung cancer.
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Affiliation(s)
- Bernhard Biersack
- Organic Chemistry Laboratory, University of Bayreuth, Universitätsstr. 30, 95447, Bayreuth, Germany.
| | - Rainer Schobert
- Organic Chemistry Laboratory, University of Bayreuth, Universitätsstr. 30, 95447, Bayreuth, Germany
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16
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Fractionated Radiation for Newly Diagnosed Supratentorial Glioblastoma Multiforme: In Regard to Brachman et al. Int J Radiat Oncol Biol Phys 2016; 94:210-211. [PMID: 26700716 DOI: 10.1016/j.ijrobp.2015.08.047] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Accepted: 08/27/2015] [Indexed: 11/20/2022]
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17
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Arambula JF, McCall R, Sidoran KJ, Magda D, Mitchell NA, Bielawski CW, Lynch VM, Sessler JL, Arumugam K. Targeting Antioxidant Pathways with Ferrocenylated N-Heterocyclic Carbene Supported Gold(I) Complexes in A549 Lung Cancer Cells. Chem Sci 2015; 7:1245-1256. [PMID: 26918111 PMCID: PMC4762604 DOI: 10.1039/c5sc03519h] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Ferrocenylated-Au(i) carbenes were designed, synthesized, and studied for their ability to generate reactive oxygen species and target antioxidant pathways via multiple mechanisms.
Ferrocene containing N-heterocyclic carbene (NHC) ligated gold(i) complexes of the type [Au(NHC)2]+ were prepared and found to be capable of regulating the formation of reactive oxygen species (ROS) via multiple mechanisms. Single crystal X-ray analysis of bis(1-(ferrocenylmethyl)-3-mesitylimidazol-2-ylidene)-gold(i) chloride (5) and bis(1,3-di(ferrocenylmethyl)imidazol-2-ylidene)-gold(i) chloride (6) revealed a quasi-linear geometry around the gold(i) centers (i.e., the C–Au–C bond angle were measured to be ∼177° and all the Au–Ccarbene bonds distances were in the range of 2.00 (7)–2.03 (1) Å). A series of cell studies indicated that cell proliferation inhibition and ROS generation were directly proportional to the amount of ferrocene contained within the [Au(NHC)2]+ complexes (IC50 of 6 < 5 < bis(1-benzyl-3-mesitylimidazol-2-ylidene)-gold(i) chloride (4)). Complexes 4–6 were also confirmed to inhibit thioredoxin reductase as inferred from lipoate reduction assays and increased chelatable intracellular zinc concentrations. RNA microarray gene expression assays revealed that 6 induces endoplasmic reticulum stress response pathways as a result of ROS increase.
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Affiliation(s)
- J F Arambula
- Department of Chemistry, Georgia Southern University, Statesboro, Georgia, 30460, USA
| | - R McCall
- Department of Chemistry, Georgia Southern University, Statesboro, Georgia, 30460, USA
| | - K J Sidoran
- Department of Chemistry, 3261 West State Road, St. Bonaventure University, New York, 14778
| | - D Magda
- Lumiphore, Inc., Berkeley, California, 94710, USA
| | - N A Mitchell
- Department of Health Sciences, Gettysburg College, Gettysburg, PA 17325-1400
| | - C W Bielawski
- Center for Multidimensional Carbon Materials (CMCM), Institute for Basic Science (IBS), Ulsan 689-798, Republic of Korea; Department of Chemistry and Department of Energy Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan 689-798, Republic of Korea
| | - V M Lynch
- Department of Chemistry, University of Texas at Austin, Austin, Texas, 78712, USA
| | - J L Sessler
- Department of Chemistry, University of Texas at Austin, Austin, Texas, 78712, USA
| | - K Arumugam
- Department of Chemistry, Wright State University, 3640 Colonel Glenn Hwy, Dayton, Ohio, 45435, USA
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18
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Lee N, Yoo D, Ling D, Cho MH, Hyeon T, Cheon J. Iron Oxide Based Nanoparticles for Multimodal Imaging and Magnetoresponsive Therapy. Chem Rev 2015; 115:10637-89. [PMID: 26250431 DOI: 10.1021/acs.chemrev.5b00112] [Citation(s) in RCA: 576] [Impact Index Per Article: 64.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Nohyun Lee
- School of Advanced Materials Engineering, Kookmin University , Seoul 136-702, Korea
| | - Dongwon Yoo
- Department of Chemistry, Yonsei University , Seoul 120-749, Korea
| | - Daishun Ling
- Center for Nanoparticle Research, Institute for Basic Science (IBS) , Seoul 151-742, Korea.,School of Chemical and Biological Engineering, Seoul National University , Seoul 151-742, Korea.,Institute of Pharmaceutics, College of Pharmaceutical Sciences, Zhejiang University , Hangzhou 310058, PR China
| | - Mi Hyeon Cho
- Department of Chemistry, Yonsei University , Seoul 120-749, Korea
| | - Taeghwan Hyeon
- Center for Nanoparticle Research, Institute for Basic Science (IBS) , Seoul 151-742, Korea.,School of Chemical and Biological Engineering, Seoul National University , Seoul 151-742, Korea
| | - Jinwoo Cheon
- Department of Chemistry, Yonsei University , Seoul 120-749, Korea
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19
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Ranjan S, Jayakumar MKG, Zhang Y. Luminescent lanthanide nanomaterials: an emerging tool for theranostic applications. Nanomedicine (Lond) 2015; 10:1477-91. [DOI: 10.2217/nnm.14.229] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Lanthanide materials have been gaining popularity for use in various theranostic applications, primarily due to their unique optical properties such as narrow emission bands, multiple emission wavelengths, emission tunability, long fluorescence lifetime and large Stokes shift. Apart from these, some lanthanide materials also exhibit magnetic and light-up conversion properties. Such nanomaterials have been used for a wide range of applications ranging from detection of biomarkers, in vitro and in vivo imaging to therapeutic applications. Recently, combined modalities of lanthanide nanomaterials for simultaneous detection/imaging and delivery of therapeutic agents (termed ‘theranostics’) have been explored. The various advantages and disadvantages of using lanthanide nanomaterials as theranostic agents and potential areas for future development have been discussed in this review.
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Affiliation(s)
- Shashi Ranjan
- Department of Biomedical Engineering, Faculty of Engineering, National University of Singapore, 117576, Singapore
| | | | - Yong Zhang
- Department of Biomedical Engineering, Faculty of Engineering, National University of Singapore, 117576, Singapore
- NUS Graduate School for Integrative Sciences & Engineering, National University of Singapore, 117456, Singapore
- Department of Biomedical Engineering, School of Medical Engineering, Hefei University of Technology, Hefei, Anhui 230009, China
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20
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Sancey L, Lux F, Kotb S, Roux S, Dufort S, Bianchi A, Crémillieux Y, Fries P, Coll JL, Rodriguez-Lafrasse C, Janier M, Dutreix M, Barberi-Heyob M, Boschetti F, Denat F, Louis C, Porcel E, Lacombe S, Le Duc G, Deutsch E, Perfettini JL, Detappe A, Verry C, Berbeco R, Butterworth KT, McMahon SJ, Prise KM, Perriat P, Tillement O. The use of theranostic gadolinium-based nanoprobes to improve radiotherapy efficacy. Br J Radiol 2014; 87:20140134. [PMID: 24990037 PMCID: PMC4453146 DOI: 10.1259/bjr.20140134] [Citation(s) in RCA: 143] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
A new efficient type of gadolinium-based theranostic agent (AGuIX®) has recently been developed for MRI-guided radiotherapy (RT). These new particles consist of a polysiloxane network surrounded by a number of gadolinium chelates, usually 10. Owing to their small size (<5 nm), AGuIX typically exhibit biodistributions that are almost ideal for diagnostic and therapeutic purposes. For example, although a significant proportion of these particles accumulate in tumours, the remainder is rapidly eliminated by the renal route. In addition, in the absence of irradiation, the nanoparticles are well tolerated even at very high dose (10 times more than the dose used for mouse treatment). AGuIX particles have been proven to act as efficient radiosensitizers in a large variety of experimental in vitro scenarios, including different radioresistant cell lines, irradiation energies and radiation sources (sensitizing enhancement ratio ranging from 1.1 to 2.5). Pre-clinical studies have also demonstrated the impact of these particles on different heterotopic and orthotopic tumours, with both intratumoural or intravenous injection routes. A significant therapeutical effect has been observed in all contexts. Furthermore, MRI monitoring was proven to efficiently aid in determining a RT protocol and assessing tumour evolution following treatment. The usual theoretical models, based on energy attenuation and macroscopic dose enhancement, cannot account for all the results that have been obtained. Only theoretical models, which take into account the Auger electron cascades that occur between the different atoms constituting the particle and the related high radical concentrations in the vicinity of the particle, provide an explanation for the complex cell damage and death observed.
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Affiliation(s)
- L Sancey
- 1 Institut Lumière Matière, UMR5306 Université Lyon 1-CNRS, Team FENNEC, Université de Lyon, Villeurbanne Cedex, France
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21
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Melisko ME, Kunwar S, Prados M, Berger MS, Park JW. Brain metastases of breast cancer. Expert Rev Anticancer Ther 2014; 5:253-68. [PMID: 15877523 DOI: 10.1586/14737140.5.2.253] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Brain metastases of breast cancer remain a difficult problem for clinical management. Their incidence appears to be increasing, which is likely due to longer survival times for advanced breast cancer patients as well as additional and improved tools for detection. Molecular features of tumors associated with this syndrome are not yet understood. In general, survival may be improving for brain metastases due to better local control in the CNS, as well as improvements in systemic disease management. Selected patients with brain metastases are able to undergo surgical resection, which has been associated with extended disease control in some patients. However, whole-brain radiation has been the mainstay for treatment for most patients. Stereotactic radiosurgery is playing an increasing role in the primary treatment of brain metastases, as well as for salvage after whole-brain radiation. Recent series have reported median survivals of 13 months or longer with stereotactic radiosurgery. Further improvements in radiation-based approaches may come from ongoing studies of radiosensitizing agents. The ability of systemic treatments to impact brain metastases has been debated, and specific treatment regimens have yet to be defined. New approaches include chemotherapy combinations, biologic therapies and novel drug-delivery strategies.
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Affiliation(s)
- Michelle E Melisko
- Division of Hematology-Oncology, University of California at San Francisco, San Francisco, CA 94115, USA.
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22
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Forouzannia A, Richards GM, Khuntia D, Mehta MP. Motexafin gadolinium: a novel radiosensitizer for brain tumors. Expert Rev Anticancer Ther 2014; 7:785-94. [PMID: 17555388 DOI: 10.1586/14737140.7.6.785] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Despite advances in the field of oncology, progress for patients with brain metastases and most primary brain tumors has been slow. New efforts to enhance the therapeutic index of radiation therapy are under way, including the use of radiosensitizers. Motexafin gadolinium (Xcytrin) is one such novel agent with several unique properties that enhance the cytotoxic potential of radiation therapy, as well as several chemotherapeutic agents, and possibly has independent cytotoxicity in certain lymphoid malignancies. Motexafin gadolinium is very well tolerated with tumor specific uptake. The rationale for the use of this drug as well as its current and future role as a radiation enhancer in the management of brain tumors is reviewed.
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Affiliation(s)
- Afshin Forouzannia
- Department of Human Oncology, University of Wisconsin School of Medicine & Public Health, Clinical Science Center, Madison, WI 53792, USA.
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23
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Kumar N, Ippel H, Weber C, Hackeng T, Mayo KH. Protein lysine-Nζ alkylation and O-phosphorylation mediated by DTT-generated reactive oxygen species. Protein Sci 2013; 22:327-46. [PMID: 23315912 DOI: 10.1002/pro.2214] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2012] [Revised: 12/11/2012] [Accepted: 12/28/2012] [Indexed: 11/07/2022]
Abstract
Reactive oxygen species (ROS) play crucial roles in physiology and pathology. In this report, we use NMR spectroscopy and mass spectrometry (MS) to demonstrate that proteins (galectin-1, ubiquitin, RNase, cytochrome c, myoglobin, and lysozyme) under reducing conditions with dithiothreitol (DTT) become alkylated at lysine-N(ζ) groups and O-phosphorylated at serine and threonine residues. These adduction reactions only occur in the presence of monophosphate, potassium, trace metals Fe/Cu, and oxygen, and are promoted by reactive oxygen species (ROS) generated via DTT oxidation. Superoxide mediates the chemistry, because superoxide dismutase inhibits the reaction, and hydroxyl and phosphoryl radicals are also likely involved. While lysine alkylation accounts for most of the adduction, low levels of phosphorylation are also observed at some serine and threonine residues, as determined by western blotting and MS fingerprinting. The adducted alkyl group is found to be a fragment of DTT that forms a Schiff base at lysine N(ζ) groups. Although its exact chemical structure remains unknown, the DTT fragment includes a SH group and a --CHOH--CH₂-- group. Chemical adduction appears to be promoted in the context of a well-folded protein, because some adducted sites in the proteins studied are considerably more reactive than others and the reaction occurs to a lesser extent with shorter, unfolded peptides and not at all with small organic molecules. A structural signature involving clusters of positively charged and other polar groups appears to facilitate the reaction. Overall, our findings demonstrate a novel reaction for DTT-mediated ROS chemistry with proteins.
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Affiliation(s)
- Nigam Kumar
- Department of Biochemistry, Molecular Biology & Biophysics, University of Minnesota, Minneapolis, Minnesota 55455, USA
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24
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Preihs C, Magda DJ, Sessler JL. Texaphyrins and water-soluble zinc(II) ionophores: development, mechanism of anticancer activity, and synergistic effects. ACTA ACUST UNITED AC 2013; 9:3-14. [PMID: 25295224 DOI: 10.1515/irm-2013-0001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Texaphyrins, first prepared by Sessler and coworkers in the 1980s, represent early examples of expanded porphyrins. This class of pentaaza, oligopyrrolic macrocycles demonstrates excellent tumor localization and metal-chelating properties. In biological milieus, texaphyrins act as redox mediators and are able to produce reactive oxygen species. Furthermore, texaphyrins have been shown to upregulate zinc in vivo, an important feature that inspired us to develop new zinc ionophores that might allow the same function to be elicited but via a simpler chemical means. In this review, the basic properties of texaphyrins and the zinc ionophores they helped spawn will be discussed in the cadre of developing an understanding that could lead to the preparation of new, redox-active anticancer agents.
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Affiliation(s)
- Christian Preihs
- Department of Chemistry and Biochemistry, University of Texas, 105 East 24th Street, Stop A5300, Austin, TX 78712-1224, USA; and Advanced Imaging Research Center, University of Texas (UT) Southwestern, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA
| | - Darren J Magda
- Lumiphore, Inc., 604 Bancroft Way, Suite B, Berkeley, CA 94710, USA
| | - Jonathan L Sessler
- Department of Chemistry and Biochemistry, University of Texas, 105 E. 24th Street, Stop A5300, Austin, TX 78712-1224, USA; and Department of Chemistry, Yonsei University, Seoul 120-749, Korea
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25
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Yoo D, Jeong H, Preihs C, Choi JS, Shin TH, Sessler JL, Cheon J. Double-effector nanoparticles: a synergistic approach to apoptotic hyperthermia. Angew Chem Int Ed Engl 2012; 51:12482-5. [PMID: 23139178 PMCID: PMC3724511 DOI: 10.1002/anie.201206400] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2012] [Indexed: 12/31/2022]
Abstract
Highly efficient apoptotic hyperthermia is achieved using a double-effector nanoparticle that can generate reactive oxygen species (ROS) and heat. ROS render cancer cells more susceptible to subsequent heat treatment, which remarkably increases the degree of apoptotic cell death. Xenograft tumors (100 mm(3)) in mice are completely eliminated within 8 days after a single mild magnetic hyperthermia treatment at 43 °C for 30 min.
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Affiliation(s)
- Dongwon Yoo
- Department of Chemistry, Yonsei University, Seoul 120-749 (Korea)
| | - Heeyeong Jeong
- Department of Chemistry, Yonsei University, Seoul 120-749 (Korea)
| | - Christian Preihs
- Department of Chemistry and Biochemistry, University of Texas, 1 University Station-A5300, Austin, TX 78712-0165 (USA)
| | - Jin-sil Choi
- Department of Chemistry, Yonsei University, Seoul 120-749 (Korea)
| | - Tae-Hyun Shin
- Department of Chemistry, Yonsei University, Seoul 120-749 (Korea)
| | - Jonathan L. Sessler
- Department of Chemistry and Biochemistry, University of Texas, 1 University Station-A5300, Austin, TX 78712-0165 (USA)
| | - Jinwoo Cheon
- Department of Chemistry, Yonsei University, Seoul 120-749 (Korea)
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26
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Yoo D, Jeong H, Preihs C, Choi JS, Shin TH, Sessler JL, Cheon J. Double-Effector Nanoparticles: A Synergistic Approach to Apoptotic Hyperthermia. Angew Chem Int Ed Engl 2012. [DOI: 10.1002/ange.201206400] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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27
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Gupta SC, Hevia D, Patchva S, Park B, Koh W, Aggarwal BB. Upsides and downsides of reactive oxygen species for cancer: the roles of reactive oxygen species in tumorigenesis, prevention, and therapy. Antioxid Redox Signal 2012; 16:1295-322. [PMID: 22117137 PMCID: PMC3324815 DOI: 10.1089/ars.2011.4414] [Citation(s) in RCA: 498] [Impact Index Per Article: 41.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
SIGNIFICANCE Extensive research during the last quarter century has revealed that reactive oxygen species (ROS) produced in the body, primarily by the mitochondria, play a major role in various cell-signaling pathways. Most risk factors associated with chronic diseases (e.g., cancer), such as stress, tobacco, environmental pollutants, radiation, viral infection, diet, and bacterial infection, interact with cells through the generation of ROS. RECENT ADVANCES ROS, in turn, activate various transcription factors (e.g., nuclear factor kappa-light-chain-enhancer of activated B cells [NF-κB], activator protein-1, hypoxia-inducible factor-1α, and signal transducer and activator of transcription 3), resulting in the expression of proteins that control inflammation, cellular transformation, tumor cell survival, tumor cell proliferation and invasion, angiogenesis, and metastasis. Paradoxically, ROS also control the expression of various tumor suppressor genes (p53, Rb, and PTEN). Similarly, γ-radiation and various chemotherapeutic agents used to treat cancer mediate their effects through the production of ROS. Interestingly, ROS have also been implicated in the chemopreventive and anti-tumor action of nutraceuticals derived from fruits, vegetables, spices, and other natural products used in traditional medicine. CRITICAL ISSUES These statements suggest both "upside" (cancer-suppressing) and "downside" (cancer-promoting) actions of the ROS. Thus, similar to tumor necrosis factor-α, inflammation, and NF-κB, ROS act as a double-edged sword. This paradox provides a great challenge for researchers whose aim is to exploit ROS stress for the development of cancer therapies. FUTURE DIRECTIONS the various mechanisms by which ROS mediate paradoxical effects are discussed in this article. The outstanding questions and future directions raised by our current understanding are discussed.
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Affiliation(s)
- Subash C Gupta
- Cytokine Research Laboratory, Department of Experimental Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
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Hagen H, Marzenell P, Jentzsch E, Wenz F, Veldwijk MR, Mokhir A. Aminoferrocene-based prodrugs activated by reactive oxygen species. J Med Chem 2012; 55:924-34. [PMID: 22185340 DOI: 10.1021/jm2014937] [Citation(s) in RCA: 194] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Cancer cells generally generate higher amounts of reactive oxygen species than normal cells. On the basis of this difference, prodrugs have been developed (e.g., hydroxyferrocifen), which remain inactive in normal cells, but become activated in cancer cells. In this work we describe novel aminoferrocene-based prodrugs, which, in contrast to hydroxyferrocifen, after activation form not only quinone methides (QMs), but also catalysts (iron or ferrocenium ions). The released products act in a concerted fashion. In particular, QMs alkylate glutathione, thereby inhibiting the antioxidative system of the cell, whereas the iron species induce catalytic generation of hydroxyl radicals. Since the catalysts are formed as products of the activation reaction, it proceeds autocatalytically. The most potent prodrug described here is toxic toward cancer cells (human promyelocytic leukemia (HL-60), IC(50) = 9 μM, and human glioblastoma-astrocytoma (U373), IC(50) = 25 μM), but not toxic (up to 100 μM) toward representative nonmalignant cells (fibroblasts).
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Affiliation(s)
- Helen Hagen
- Institute of Inorganic Chemistry, Ruprecht-Karls-University of Heidelberg, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany
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29
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Lee MH, Han JH, Kwon PS, Bhuniya S, Kim JY, Sessler JL, Kang C, Kim JS. Hepatocyte-targeting single galactose-appended naphthalimide: a tool for intracellular thiol imaging in vivo. J Am Chem Soc 2012; 134:1316-22. [PMID: 22171762 DOI: 10.1021/ja210065g] [Citation(s) in RCA: 355] [Impact Index Per Article: 29.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
We present the design, synthesis, spectroscopic properties, and biological evaluation of a single galactose-appended naphthalimide (1). Probe 1 is a multifunctional molecule that incorporates a thiol-specific cleavable disulfide bond, a masked phthalamide fluorophore, and a single galactose moiety as a hepatocyte-targeting unit. It constitutes a new type of targetable ligand for hepatic thiol imaging in living cells and animals. Confocal microscopic imaging experiments reveal that 1, but not the galactose-free control system 2, is preferentially taken up by HepG2 cells through galactose-targeted, ASGP-R-mediated endocytosis. Probe 1 displays a fluorescence emission feature at 540 nm that is induced by exposure to free endogenous thiols, most notably GSH. The liver-specificity of 1 was confirmed in vivo via use of a rat model. The potential utility of this probe in indicating pathogenic states and as a possible screening tool for agents that can manipulate oxidative stress was demonstrated in experiments wherein palmitate was used to induce lipotoxicity in HepG2 cells.
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Affiliation(s)
- Min Hee Lee
- Department of Chemistry, Korea University, Seoul, 136-701, Korea
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Multicenter phase II trial of Motexafin gadolinium and pemetrexed for second-line treatment in patients with non-small cell lung cancer. J Thorac Oncol 2011; 6:786-9. [PMID: 21289521 DOI: 10.1097/jto.0b013e31820a443f] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Motexafin gadolinium (MGd) disrupts redox-dependent pathways by inhibiting oxidative stress-related proteins leading to apoptosis. MGd selectively targets tumor cells, disrupting energy metabolism and repair mechanisms, rendering cells more prone to apoptosis. Preclinical studies with MGd and pemetrexed show significant tumor growth delay in lung cancer cell lines. METHODS Patients with non-small cell lung cancer, Eastern Cooperative Oncology Group performance status 0 to 1, who had received one previous platinum containing regimen and normal organ function were treated with MGd 15 mg/kg and pemetrexed 500 mg/m q21days. Patients were allowed to receive more than one regimen if the initial treatment was in the adjuvant or curative setting and administered >12 months earlier. The primary end point was to demonstrate a 40% rate of 6-month progression free survival (PFS). RESULTS Seventy-two patients (30 women, 42 men), performance status 0/1 (30/42), and a median age of 63 years were enrolled. Most patients (96%) were current or former smokers. All histologic types were represented (squamous/adenocarcinoma/other: 28%, 42%, 31%). Number of prior regimens: 1: 69%; 2: 26%, and >2: 4%. Median number of cycles administered was (range) 2 (1-12). TOXICITY grade 3/4 neutropenia was noted in 8.3% with febrile neutropenia in 1.4%, thrombocytopenia in 8.3%, fatigue in 9.7%, and pneumonia in 11.1%. There were no complete responses, 8.1% had partial response, 56.5% had stable disease, and 35.5% had progressive disease as their best response. Twenty-three percent of patients were progression free at 6 months and the median PFS was 2.6 months with an overall survival of 8.1 months. CONCLUSIONS The combination of MGd and pemetrexed was well tolerated with toxicity similar to that of pemetrexed alone. However, the study did not achieve its end point of 40% 6-month PFS. The response rate, PFS, and overall survival did not seem markedly different than prior phase II and phase III studies of pemetrexed alone. Consequently, there are no further plans for development of this combination.
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31
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Six degrees of separation: the oxygen effect in the development of radiosensitizers. Transl Oncol 2011; 4:189-98. [PMID: 21804913 DOI: 10.1593/tlo.11166] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2011] [Revised: 05/06/2011] [Accepted: 05/11/2011] [Indexed: 11/18/2022] Open
Abstract
The popular theory six degrees of separation is used in this review as an analogy to relate all radiosensitization to oxygen. As the prime mover of all radiosensitizers, the pervasive influence of oxygen has consciously or unconsciously influenced the direction of research and development and provided the benchmark against which all other compounds and approaches are measured. It is the aim of this review to develop the six degrees of separation from oxygen analogy as a unifying framework for conceptually organizing the field and for giving context to its varied subspecializations and theories. Under such a framework, it would become possible for one area to consider questions and problems found in other areas of radiosensitization, using a common analogy, that would allow for further development and unification of this multifaceted discipline. In this review, approaches to the development of radiosensitizers and the current state of research in this field are discussed, including promising new agents in various stages of clinical development.
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Prast-Nielsen S, Dexheimer TS, Schultz L, Stafford WC, Cheng Q, Xu J, Jadhav A, Arnér ESJ, Simeonov A. Inhibition of thioredoxin reductase 1 by porphyrins and other small molecules identified by a high-throughput screening assay. Free Radic Biol Med 2011; 50:1114-23. [PMID: 21262347 PMCID: PMC3070820 DOI: 10.1016/j.freeradbiomed.2011.01.020] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2010] [Revised: 01/03/2011] [Accepted: 01/13/2011] [Indexed: 11/25/2022]
Abstract
The selenoprotein thioredoxin reductase 1 (TrxR1) has in recent years been identified as a promising anticancer drug target. A high-throughput assay for discovery of novel compounds targeting the enzyme is therefore warranted. Herein, we describe a single-enzyme, dual-purpose assay for simultaneous identification of inhibitors and substrates of TrxR1. Using this assay to screen the LOPAC¹²⁸⁰ compound collection we identified several known inhibitors of TrxR1, thus validating the assay, as well as several compounds hitherto unknown to target the enzyme. These included rottlerin (previously reported as a PKCδ inhibitor and mitochondrial uncoupler) and the heme precursor protoporphyrin IX (PpIX). We found that PpIX was a potent competitive inhibitor of TrxR1, with a K(i)=2.7 μM with regard to Trx1, and in the absence of Trx1 displayed time-dependent irreversible inhibition with an apparent second-order rate constant (k(inact)) of (0.73 ± 0.07) × 10⁻³ μM⁻¹ min⁻¹. Exogenously delivered PpIX was cytotoxic, inhibited A549 cell proliferation, and was found to also inhibit cellular TrxR activity. Hemin and the ferrochelatase inhibitor NMPP also inhibited TrxR1 and showed cytotoxicity, but less potently compared to PpIX. We conclude that rottlerin-induced cellular effects may involve targeting of TrxR1. The unexpected finding of PpIX as a TrxR1 inhibitor suggests that such inhibition may contribute to symptoms associated with conditions of abnormally high PpIX levels, such as reduced ferrochelatase activity seen in erythropoietic protoporphyria. Finally, additional inhibitors of TrxR1 may be discovered and further characterized based upon the new high-throughput TrxR1 assay presented here.
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Affiliation(s)
- Stefanie Prast-Nielsen
- Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE-171 77 Stockholm, Sweden
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McHaffie DR, Chabot P, Dagnault A, Suh JH, Fortin MA, Chang E, Timmerman R, Souhami L, Grecula J, Nabid A, Schultz C, Werner-Wasik M, Gaspar LE, Brachman D, Mody T, Mehta MP. Safety and feasibility of motexafin gadolinium administration with whole brain radiation therapy and stereotactic radiosurgery boost in the treatment of ≤ 6 brain metastases: a multi-institutional phase II trial. J Neurooncol 2011; 105:301-8. [PMID: 21523486 DOI: 10.1007/s11060-011-0590-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2010] [Accepted: 04/18/2011] [Indexed: 01/03/2023]
Abstract
To determine the safety, tolerability, and report on secondary efficacy endpoints of motexafin gadolinium (MGd) in combination with whole-brain radiotherapy (WBRT) and stereotactic radiosurgery (SRS) for patients with ≤ 6 brain metastases. We conducted an international study of WBRT (37.5 Gy in 15 fractions) and SRS (15-21 Gy) with the addition of MGd (5 mg/kg preceding each fraction beginning week 2). The primary endpoint was to evaluate the rate of irreversible grade 3 or any grade ≥ 4 neurotoxicity and establish feasibility in preparation for a phase III trial. Sixty-five patients were enrolled from 14 institutions, of which 45 (69%) received SRS with MGd as intended and were available for evaluation. Grade ≥ 3 neurotoxicity attributable to radiation therapy within 3 months of SRS was seen in 2 patients (4.4%), including generalized weakness and radionecrosis requiring surgical management. Immediately following the course of MGd plus WBRT, new brain metastases were detected in 11 patients (24.4%) at the time of the SRS treatment planning MRI. The actuarial incidence of neurologic progression at 6 months and 1 year was 17 and 20%, respectively. The median investigator-determined neurologic progression free survival and overall survival times were 8 (95% CI: 5-14) and 9 months (95% CI: 6-not reached), respectively. We observed a low rate of neurotoxicity, demonstrating that the addition of MGd does not increase the incidence or severity of neurologic complications from WBRT with SRS boost.
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Affiliation(s)
- Derek R McHaffie
- Department of Human Oncology, University of Wisconsin School of Medicine and Public Health, 600 Highland Ave, K4/B100, Madison, WI 53792, USA.
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Berndt C, Kurz T, Bannenberg S, Jacob R, Holmgren A, Brunk UT. Ascorbate and endocytosed Motexafin gadolinium induce lysosomal rupture. Cancer Lett 2011; 307:119-23. [PMID: 21492999 DOI: 10.1016/j.canlet.2011.03.023] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2011] [Revised: 03/21/2011] [Accepted: 03/28/2011] [Indexed: 11/25/2022]
Abstract
Motexafin gadolinium (MGd) sensitizes malignant cells to ionizing radiation, although the underlying mechanisms for uptake and sensitization are both unclear. Here we show that MGd is endocytosed by the clathrin-dependent pathway with ensuing lysosomal membrane permeabilization, most likely via formation of reactive oxygen species involving redox-active metabolites, such as ascorbate. We propose that subsequent apoptosis is a synergistic effect of irradiation and high MGd concentrations in malignant cells due to their pronounced endocytic activity. The results provide novel insights into the mode of action of this promising anti-cancer drug, which is currently under clinical trials.
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Affiliation(s)
- Carsten Berndt
- Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
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Javvadi P, Hertan L, Kosoff R, Datta T, Kolev J, Mick R, Tuttle SW, Koumenis C. Thioredoxin reductase-1 mediates curcumin-induced radiosensitization of squamous carcinoma cells. Cancer Res 2010; 70:1941-50. [PMID: 20160040 DOI: 10.1158/0008-5472.can-09-3025] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Curcumin, a plant polyphenol, is a widely studied chemopreventive agent with demonstrated antitumor activities in preclinical studies and low toxicity profiles in multiple clinical trials against human malignancies. We previously showed that curcumin radiosensitizes cervical tumor cells without increasing the cytotoxic effects of radiation on normal human fibroblasts. Here we report that an inhibitory activity of curcumin on the antioxidant enzyme thioredoxin reductase-1 (TxnRd1) is required for curcumin-mediated radiosensitization of squamous carcinoma cells. Stable knockdown of TxnRd1 in both HeLa and FaDu cells nearly abolished curcumin-mediated radiosensitization. TxnRd1 knockdown cells showed decreased radiation-induced reactive oxygen species and sustained extracellular signal-regulated kinase 1/2 activation, which we previously showed was required for curcumin-mediated radiosensitization. Conversely, overexpressing catalytically active TxnRd1 in HEK293 cells, with low basal levels of TxnRd1, increased their sensitivity to curcumin alone and to the combination of curcumin and ionizing radiation. These results show the critical role of TxnRd1 in curcumin-mediated radiosensitization and suggest that TxnRd1 levels in tumors could have clinical value as a predictor of response to curcumin and radiotherapy.
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Affiliation(s)
- Prashanthi Javvadi
- Department of Cancer Biology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104, USA
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Evens AM, Spies WG, Helenowski IB, Patton D, Spies S, Jovanovic BD, Miyata S, Hamilton E, Variakojis D, Chen J, Naumovski L, Rosen ST, Winter JN, Miller RA, Gordon LI. The novel expanded porphyrin, motexafin gadolinium, combined with [90Y]ibritumomab tiuxetan for relapsed/refractory non-Hodgkin's lymphoma: preclinical findings and results of a phase I trial. Clin Cancer Res 2009; 15:6462-71. [PMID: 19825958 PMCID: PMC2763343 DOI: 10.1158/1078-0432.ccr-09-0905] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE Therapeutic strategies to enhance the efficacy of radioimmunotherapy have not been explored. Motexafin gadolinium is a novel anticancer agent that targets redox-dependent pathways and enhances sensitivity of tumor cells to ionizing radiation. EXPERIMENTAL DESIGN We did preclinical studies examining motexafin gadolinium combined with rituximab and/or radiation in lymphoma cells. We subsequently completed a phase I clinical trial combining escalating doses of motexafin gadolinium concurrently with standard [(90)Y]ibritumomab tiuxetan for patients with relapsed/refractory non-Hodgkin's lymphoma. RESULTS In HF1 lymphoma cells, motexafin gadolinium and rituximab resulted in synergistic cytotoxicity (combination index, 0.757) through a mitochondrial-mediated caspase-dependent pathway, whereas cell death in Ramos and SUDHL4 cells was additive. Motexafin gadolinium/rituximab combined with radiation (1-3 Gy) resulted in additive apoptosis. Twenty-eight of 30 patients were evaluable on the phase I clinical trial. Median age was 65 years (47-87 years), and histologies were marginal-zone (n = 1), mantle-cell (n = 3), diffuse large cell (n = 6), and follicular lymphoma (n = 18). Of all patients, 86% were rituximab refractory. Therapy was well tolerated, and no dose-limiting toxicity was seen. Overall response rate was 57% [complete remission (CR), 43%], with median time-to-treatment failure of 10 months (1-48+ months) and median duration-of-response of 17 months. Of note, all responses were documented at 4 weeks. Furthermore, in rituximab-refractory follicular lymphoma (n = 14), overall response rate was 86% (CR, 64%), with a median time-to-treatment failure of 14 months (2-48+ months). CONCLUSIONS This represents the first report of a novel agent to be combined safely concurrently with radioimmunotherapy. Furthermore, tumor responses with [(90)Y]ibritumomab tiuxetan/motexafin gadolinium were prompt with a high rate of CRs, especially in rituximab-refractory follicular lymphoma.
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Affiliation(s)
- Andrew M Evens
- Lymphoma Program, Division of Hematology/Oncology, The Robert H. Lurie Comprehensive Cancer Center, Northwestern University Feinberg School of Medicine, 676 North St. Clair Street, Chicago, IL 60611, USA.
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Francis D, Richards GM, Forouzannia A, Mehta MP, Khuntia D. Motexafin gadolinium: a novel radiosensitizer for brain tumors. Expert Opin Pharmacother 2009; 10:2171-80. [PMID: 19640206 DOI: 10.1517/14656560903179325] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
For a variety of reasons, the management of brain tumors, both primary and metastatic, remains a considerable challenge. As most systemic therapies do not cross the BBB at therapeutic doses, radiation and surgery have played primary roles in the management of these diseases. Despite significant advances in surgical techniques and radiation delivery, outcomes for most adult brain tumors continue to be poor. In an effort to enhance the effects of radiation in the brain, a variety of radiation sensitizers, including motexafin gadolinium, have been investigated. In the following manuscript, we summarize motexafin gadolinium and its role in brain tumors.
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Affiliation(s)
- Dave Francis
- University of Wisconsin School of Medicine and Public Health, 600 Highland Avenue, K4-B100 Madison, WI 53717, USA
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Tonissen KF, Di Trapani G. Thioredoxin system inhibitors as mediators of apoptosis for cancer therapy. Mol Nutr Food Res 2009; 53:87-103. [PMID: 18979503 DOI: 10.1002/mnfr.200700492] [Citation(s) in RCA: 171] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The thioredoxin (Trx) system is a major antioxidant system integral to maintaining the intracellular redox state. It contains Trx, a redox active protein, which regulates the activity of various enzymes including those that function to counteract oxidative stress within the cell. Trx can also scavenge reactive oxygen species (ROS) and directly inhibits proapoptotic proteins such as apoptosis signal-regulating kinase 1 (ASK1). The oxidized form of Trx is reduced by thioredoxin reductase (TrxR). The cytoplasm and mitochondria contain equivalent Trx systems and inhibition of either system can lead to activation of apoptotic signaling pathways. There are a number of inhibitors with chemotherapy applications that target either Trx or TrxR to induce apoptosis in cancer cells. Suberoylanilide hydroxamic acid (SAHA) is effective against many cancer cells and functions by up-regulating an endogenous inhibitor of Trx. Other compounds target the selenocysteine-containing active site of TrxR. These include gold compounds, platinum compounds, arsenic trioxide, motexafin gadolinium, nitrous compounds, and various flavonoids. Inhibition of TrxR leads to an accumulation of oxidized Trx resulting in cellular conditions that promote apoptosis. In addition, some compounds also convert TrxR to a ROS generating enzyme. The role of Trx system inhibitors in cancer therapy is discussed in this review.
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Affiliation(s)
- Kathryn F Tonissen
- School of Biomolecular and Physical Sciences, Griffith University, Nathan, Qld, Australia.
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Zahedi Avval F, Berndt C, Pramanik A, Holmgren A. Mechanism of inhibition of ribonucleotide reductase with motexafin gadolinium (MGd). Biochem Biophys Res Commun 2009; 379:775-9. [PMID: 19121624 DOI: 10.1016/j.bbrc.2008.12.128] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2008] [Accepted: 12/20/2008] [Indexed: 12/21/2022]
Abstract
Motexafin gadolinium (MGd) is an expanded porphyrin anticancer agent which selectively targets tumor cells and works as a radiation enhancer, with promising results in clinical trials. Its mechanism of action is oxidation of intracellular reducing molecules and acting as a direct inhibitor of mammalian ribonucleotide reductase (RNR). This paper focuses on the mechanism of inhibition of RNR by MGd. Our experimental data present at least two pathways for inhibition of RNR; one precluding subunits oligomerization and the other direct inhibition of the large catalytic subunit of the enzyme. Co-localization of MGd and RNR in the cytoplasm particularly in the S-phase may account for its inhibitory properties. These data can elucidate an important effect of MGd on the cancer cells with overproduction of RNR and its efficacy as an anticancer agent and not only as a general radiosensitizer.
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Affiliation(s)
- Farnaz Zahedi Avval
- Department of Medical Biochemistry and Biophysics, Karolinska Institute, Stockholm, Sweden
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Lartigau E, Dewas S, Gras L. L’effet Oxygène, une cible ancienne toujours d’actualité ? Cancer Radiother 2008; 12:42-9. [DOI: 10.1016/j.canrad.2007.12.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2007] [Revised: 12/10/2007] [Accepted: 12/12/2007] [Indexed: 01/18/2023]
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Rozanova Torshina N, Zhang JZ, Heck DE. Catalytic therapy of cancer with ascorbate and extracts of medicinal herbs. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2007; 7:203-12. [PMID: 18955293 PMCID: PMC2862925 DOI: 10.1093/ecam/nem159] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/24/2007] [Accepted: 07/18/2007] [Indexed: 12/02/2022]
Abstract
Catalytic therapy (CT) is a cancer treatment modality based on the generation of reactive oxygen species (ROS) using a combination of substrate molecules and a catalyst. The most frequently used substrate/catalyst pair is ascorbate/Co phthalocyanine (PcCo). In the present work, herb extracts containing pigments have been studied as a catalyst in place of PcCo. Extracts from herbs are expected to have efficiency comparable with that of phthalocyanines but as natural products, to exhibit fewer side effects. The present studies demonstrate that a combined use of ascorbate and herbal extracts results in ROS production and a significant decrease in the number of cancer cells after a single in vitro treatment. Treatment with ascorbate in conjunction with extracts prepared from several medicinal herbs stimulated apoptosis and disrupted the cell cycle. The number of cells accumulating in the sub-G0/G1 stage of the cell cycle was increased 2- to 7-fold, and cells in G2/M increased 1.5- to 20-fold, indicating that the treatment protocol was highly effective in suppressing DNA synthesis and potentially reflecting DNA damage in the tumor cells. In addition, 20–40% of the cells underwent apoptosis within 24 h of completing treatment. Our results suggest that herbal extracts can function as CT catalysts in the treatment of cancer.
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Affiliation(s)
- Nadejda Rozanova Torshina
- Department of Chemistry and Biochemistry, University of California, Santa Cruz, CA 95064 and Department of Cancer Biology and Pharmacology, University of Illinois College of Medicine, Peoria, IL 61605, USA
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William WN, Zinner RG, Karp DD, Oh YW, Glisson BS, Phan SC, Stewart DJ. Phase I trial of motexafin gadolinium in combination with docetaxel and cisplatin for the treatment of non-small cell lung cancer. J Thorac Oncol 2007; 2:745-50. [PMID: 17762342 DOI: 10.1097/jto.0b013e31811f4719] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
INTRODUCTION Motexafin gadolinium is a novel antineoplastic drug that disrupts cancer cell antioxidant systems, thus contributing to cellular death. In patients with lung cancer, motexafin gadolinium has been shown to increase the time to neurologic progression when given in combination with whole-brain radiotherapy in randomized phase III studies. Preclinical data suggest that this drug might also enhance the antineoplastic effects of chemotherapy. METHODS In this one-arm, open label, phase I, dose-escalation study, we administered docetaxel (75 mg/m2), cisplatin (75 mg/m2), and motexafin gadolinium every 3 weeks to patients with metastatic non-small cell lung cancer. Twenty-one patients were treated at one of four motexafin dose levels. RESULTS The maximal tolerated motexafin dose was 10 mg/kg on day 1 of a 3-week cycle. Dose-limiting toxicities consisted of febrile neutropenia, hypertension, myocardial ischemia, and pneumonitis/pulmonary infiltrates. Other common grade 3-4 adverse events across all cohorts that did not appear to be exacerbated by motexafin gadolinium included granulocytopenia, fatigue, dehydration, nausea, and vomiting. Two episodes of myocardial ischemia and one sudden death of unknown cause were observed. Response rates were partial response (10%), stable disease (60%), and disease progression (30%). CONCLUSIONS The regimen studied was tolerable and showed activity in patients with metastatic non-small cell lung cancer. The recommended doses for future phase II trials are motexafin gadolinium 10 mg/kg, docetaxel 75 mg/m2, and cisplatin 75 mg/m2 intravenously on day 1 every 3 weeks. Caution is advised in patients with a history of cardiovascular disease.
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Affiliation(s)
- William N William
- Department of Thoracic/Head and Neck Medical Oncology, The University of Texas M.D. Anderson Cancer Center, Houston, Texas 77030, USA
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Thomas SR, Khuntia D. Motexafin gadolinium injection for the treatment of brain metastases in patients with non-small cell lung cancer. Int J Nanomedicine 2007; 2:79-87. [PMID: 17722515 PMCID: PMC2673824 DOI: 10.2147/nano.2007.2.1.79] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Despite recent advances in technology, targeting, and chemotherapy, brain metastasis from non-small cell lung cancer (NSCLC) remains a significant problem. The vast majority of patients with this diagnosis undergo whole brain radiation therapy (WBRT). However, outcomes are still quite poor with median survivals measured in only months. In an effort to enhance outcomes from external beam radiation treatments, radiosensitizers have been investigated. Motexafin gadolinium (MGd) (Xcytrin®, Sunnyvale, CA, USA) is a novel radiation sensitizer with a unique mechanism of action that may increase the therapeutic index of WBRT for patients with brain metastases, particularly in those with NSCLC histologies. Here we review the rationale for the use of this drug as well as its current and future role as a radiation enhancer in the management of NSCLC brain metastasis.
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Affiliation(s)
| | - Deepak Khuntia
- Correspondence: Deepak Khuntia, 600 Highland Avenue, K4-B100, Madison, WI 53792, USA, Tel +1 608 263 8500, Fax +1 608 263 9167, Email
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Ford JM, Seiferheld W, Alger JR, Wu G, Endicott TJ, Mehta M, Curran W, Phan SC. Results of the phase I dose-escalating study of motexafin gadolinium with standard radiotherapy in patients with glioblastoma multiforme. Int J Radiat Oncol Biol Phys 2007; 69:831-8. [PMID: 17560737 DOI: 10.1016/j.ijrobp.2007.04.017] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2006] [Revised: 04/04/2007] [Accepted: 04/13/2007] [Indexed: 11/27/2022]
Abstract
PURPOSE Motexafin gadolinium (MGd) is a putative radiation enhancer initially evaluated in patients with brain metastases. This Phase I trial studied the safety and tolerability of a 2-6-week course (10-22 doses) of MGd with radiotherapy for glioblastoma multiforme. METHODS AND MATERIALS A total of 33 glioblastoma multiforme patients received one of seven MGd regimens starting at 10 doses of 4 mg/kg/d MGd and escalating to 22 doses of 5.3 mg/kg/d MGd (5 or 10 daily doses then three times per week). The National Cancer Institute Cancer Therapy Evaluation Program toxicity and stopping rules were applied. RESULTS The maximal tolerated dose was 5.0 mg/kg/d MGd (5 d/wk for 2 weeks, then three times per week) for 22 doses. The dose-limiting toxicity was reversible transaminase elevation. Adverse reactions included rash/pruritus (45%), chills/fever (30%), and self-limiting vesiculobullous rash of the thumb and fingers (42%). The median survival of 17.6 months prompted a case-matched analysis. In the case-matched analysis, the MGd patients had a median survival of 16.1 months (n = 31) compared with the matched Radiation Therapy Oncology Group database patients with a median survival of 11.8 months (hazard ratio, 0.43; 95% confidence interval, 0.20-0.94). CONCLUSION The maximal tolerated dose of MGd with radiotherapy for glioblastoma multiforme in this study was 5 mg/kg/d for 22 doses (daily for 2 weeks, then three times weekly). The baseline survival calculations suggest progression to Phase II trials is appropriate, with the addition of MGd to radiotherapy with concurrent and adjuvant temozolomide.
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Affiliation(s)
- Judith M Ford
- Department of Radiation Oncology, University of California, Los Angeles, School of Medicine, Los Angeles, CA 90095-6951, USA.
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Wardman P. Chemical radiosensitizers for use in radiotherapy. Clin Oncol (R Coll Radiol) 2007; 19:397-417. [PMID: 17478086 DOI: 10.1016/j.clon.2007.03.010] [Citation(s) in RCA: 307] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2007] [Accepted: 03/13/2007] [Indexed: 12/21/2022]
Abstract
Radiosensitizers are intended to enhance tumour cell killing while having much less effect on normal tissues. Some drugs target different physiological characteristics of the tumour, particularly hypoxia associated with radioresistance. Oxygen is the definitive hypoxic cell radiosensitizer, the large differential radiosensitivity of oxic vs hypoxic cells being an attractive factor. The combination of nicotinamide to reduce acute hypoxia with normobaric carbogen breathing is showing clinical promise. 'Electron-affinic' chemicals that react with DNA free radicals have the potential for universal activity to combat hypoxia-associated radioresistance; a nitroimidazole, nimorazole, is clinically effective at tolerable doses. Hypoxia-specific cytotoxins, such as tirapazamine, are valuable adjuncts to radiotherapy. Nitric oxide is a potent hypoxic cell radiosensitizer; variations in endogenous levels might have prognostic significance, and routes to deliver nitric oxide specifically to tumours are being developed. In principle, many drugs can be delivered selectively to hypoxic tumours using either reductase enzymes or radiation-produced free radicals to activate drug release from electron-affinic prodrugs. A redox-active agent based on a gadolinium chelate is being evaluated clinically. Pyrimidines substituted with bromine or iodine are incorporated into DNA and enhance free radical damage; fluoropyrimidines act by different mechanisms. A wide variety of drugs that influence the nature or repair of DNA damage are being evaluated in conjunction with radiation; it is often difficult to define the mechanisms underlying chemoradiation regimens. Drugs being evaluated include topoisomerase inhibitors (e.g. camptothecin, topotecan), and the hypoxia-activated anthraquinone AQ4N; alkylating agents include temozolomide. Drugs involved in DNA repair pathways being investigated include the potent poly(ADP ribose)polymerase inhibitor, AG14,361. Proteins involved in cell signalling, such as the Ras family, are attractive targets linked to radioresistance, as are epidermal growth factor receptors and linked kinases (drugs including vandetanib [ZD6,474], cetuximab and gefitinib), and cyclooxygenase-2 (celecoxib). The suppression of radioprotective thiols seems to offer more potential with alkylating agents than with radiotherapy, although it remains a strategy worthy of exploration.
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Affiliation(s)
- P Wardman
- University of Oxford, Gray Cancer Institute, PO Box 100, Mount Vernon Hospital, Northwood HA6 2JR, UK.
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Rozanova Torshina N, Zhang JZ, Heck DE. Catalytic therapy of cancer with porphyrins and ascorbate. Cancer Lett 2007; 252:216-24. [PMID: 17275175 DOI: 10.1016/j.canlet.2006.12.026] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2006] [Revised: 12/19/2006] [Accepted: 12/20/2006] [Indexed: 10/23/2022]
Abstract
Catalytic therapy (CT) is a cancer treatment modality based on the generation of reactive oxygen species (ROS) using a combination of substrate molecules and a catalyst. The most frequently used substrate and catalyst pair is ascorbate/Co phthalocyanine (PcCo). In the present study, porphyrins containing transition metal ions as catalysts in place of PcCo were studied. Porphyrins that are expected to be as efficient as phthalocyanines, but may have fewer side effects, were analyzed. ROS production through the combined use of ascorbate and porphyrins decreased the number of breast cancer tumor cells by 20-40% after a single in vitro treatment, as compared to control cells. Treatment with ascorbate in conjunction with porphyrins stimulated apoptosis and disrupted the cell cycle. These treatments enhanced apoptosis by 20-40% when compared to treatments with ascorbate and porphyrins. In addition, the number of cells accumulating in the sub G0/G1 stage of the cell cycle increased from 3- to 10-fold, potentially reflecting that the treatment was highly effective in inducing DNA damage in the tumor cells, suggesting that porphyrins may be beneficial as a CT catalyst in the treatment of cancer.
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Abstract
Motexafin gadolinium (MGd) is a novel, MRI-detectable, anticancer agent that enhances the cytotoxic potential of radiation therapy through several mechanisms, including depleting intracellular reducing metabolites that are necessary for repairing the oxidative damage induced by irradiation. It has tumor-specific uptake, normal tissue sparing, and tolerable and reversible toxicities in clinical trials. MGd's use in conjunction with whole-brain radiation therapy (WBRT) has demonstrated an improvement in neurocognitive decline, neurologic progression, and quality of life in patients with brain metastases from NSCLC. Its use in conjunction with radiosurgery and whole brain radiation therapy in the setting of brain metastases is currently being studied, as is MGd with radiation and temozolomide in patients with glioblastoma multiforme. MGd is also being actively investigated as a single agent or in combination with chemotherapy or radiation therapy in other tumors, including pediatric brain tumors, NSCLC, lymphoma, renal cell carcinoma, and pancreatic and biliary tumors.
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Affiliation(s)
- Gregory M Richards
- University of Wisconsin School of Medicine and Public Health, Department of Human Oncology, Madison, WI 53792, USA
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48
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Abstract
Motexafin gadolinium (MGd, Xcytrin) is an aromatic macrocycle that has a strong affinity for electrons, i.e., it is easily reduced. In the presence of oxygen, MGd accepts electrons from various cellular reducing metabolites and forms superoxide and other reactive oxygen species (ROS) by redox cycling. The reaction with NADPH is dramatically accelerated by various oxido-reductases including thioredoxin reductase. In vitro studies with various cancer cell lines have shown an increase in ROS and intracellular free zinc in cells treated with MGd. MGd increases cytotoxicity of ionizing radiation and various chemotherapy agents and may be directly cytotoxic to tumor cells under certain conditions. MGd selectively localizes in tumors, perhaps due to their metabolic perturbations. MGd treatment in murine models enhances tumor response to radiation and chemotherapy agents. In controlled, randomized clinical trials, combining MGd treatment with ionizing radiation improves time to neurologic progression in lung cancer patients with brain metastases. The molecular target for MGd appears to be thioredoxin reductase which, when inhibited, results in cellular redox stress, cytotoxicity and an increase in tumor responsiveness to a variety of treatments.
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Affiliation(s)
- Darren Magda
- Pharmacyclics Inc., 995 E. Arques Avenue, Sunnyvale, CA 94085, USA
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Evans JP, Xu F, Sirisawad M, Miller R, Naumovski L, de Montellano PRO. Motexafin gadolinium-induced cell death correlates with heme oxygenase-1 expression and inhibition of P450 reductase-dependent activities. Mol Pharmacol 2006; 71:193-200. [PMID: 17018578 DOI: 10.1124/mol.106.028407] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Heme oxygenase-1 (HO1), which oxidizes heme to biliverdin, CO, and free iron, conveys protection against oxidative stress and is antiapoptotic. Under stress conditions, some porphyrin derivatives can inhibit HO1 and trigger cell death. Motexafin gadolinium (MGd) is an expanded porphyrin that selectively targets cancer cells through a process of futile redox cycling that decreases intracellular reducing metabolites and protein thiols. Here, we report that hematopoietic-derived cell lines that constitutively express HO1 are more susceptible to MGd-induced apoptosis than those that do not. MGd used in combination with tin protoporphyrin IX, an inhibitor of HO1, resulted in synergistic cell killing. Consistent with these cell culture observations, we found that MGd is an inhibitor of heme oxygenase-1 activity in vitro. We demonstrate that inhibition of HO1 reflects an interaction of MGd with NADPH-cytochrome P450 reductase, the electron donor for HO1, that results in diversion of reducing equivalents from heme oxidation to oxygen reduction. In accord with this mechanism, MGd is also an in vitro inhibitor of CYP2C9, CYP3A4, and CYP4A1. Inhibition of HO1 by MGd may contribute to its anticancer activity, whereas its in vitro inhibition of a broad spectrum of P450 enzymes indicates that a potential exists for drug-drug interactions.
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Affiliation(s)
- John P Evans
- Department of Pharmaceutical Chemistry, University of California, San Francisco, 600 16th St., San Francisco, CA 94143-2280, USA
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Ramos J, Sirisawad M, Miller R, Naumovski L. Motexafin gadolinium modulates levels of phosphorylated Akt and synergizes with inhibitors of Akt phosphorylation. Mol Cancer Ther 2006; 5:1176-82. [PMID: 16731749 DOI: 10.1158/1535-7163.mct-05-0280] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Motexafin gadolinium (MGd, Xcytrin) is a tumor-selective expanded porphyrin that targets oxidative stress-related proteins. MGd treatment of the follicular lymphoma-derived cell line HF-1 resulted in growth suppression and apoptosis whereas MGd treatment of the Burkitt's lymphoma-derived cell line Ramos resulted in growth suppression but not apoptosis. Because phosphorylation status of Akt/protein kinase B is regulated by oxidative stress, we monitored total and phosphorylated Akt (pAkt) in MGd-treated HF-1 and Ramos cells. Levels of pAkt increased within 30 minutes after MGd treatment of HF-1 but after 4 hours began to show a progressive decline to below baseline levels before cells underwent apoptosis. In MGd-treated Ramos cells, pAkt increased approximately 2-fold within 4 hours and remained persistently elevated. Because pAkt activates survival pathways, we determined if MGd-induced cell death could be enhanced by inhibiting phosphorylation of Akt. The addition of specific inhibitors of Akt phosphorylation (Akt inhibitor 1 or SH-5) reduced pAkt levels in MGd-treated HF-1 and Ramos cells and synergistically enhanced MGd-induced cell death. MGd was also evaluated in combination with celecoxib, an inhibitor of Akt phosphorylation, or docetaxel, a microtubule inhibitor that can decrease Akt phosphorylation. The combination of MGd/celecoxib or MGd/docetaxel resulted in decreased Akt phosphorylation and in synergistic cytotoxicity compared with either agent alone. These data point to a potential protective role for pAkt in MGd-induced apoptosis and suggest that MGd activity may be enhanced by combining it with agents that inhibit Akt phosphorylation.
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Affiliation(s)
- Jason Ramos
- Pharmacyclics, Inc., 995 Arques Avenue, Sunnyvale, CA 94085, USA
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