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Akleev AV, Shaposhnikova IA, Churilova IV, Grebenyuk AN, Pryakhin EA. The Influence of the Superoxide Dismutase Preparation Rexod® on Survival of CFU–S in С57ВL/6 Mice Exposed to Irradiation. BIOL BULL+ 2022. [DOI: 10.1134/s1062359021110029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Radiobiological Studies of Microvascular Damage through In Vitro Models: A Methodological Perspective. Cancers (Basel) 2021; 13:cancers13051182. [PMID: 33803333 PMCID: PMC7967181 DOI: 10.3390/cancers13051182] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 03/01/2021] [Accepted: 03/03/2021] [Indexed: 12/12/2022] Open
Abstract
Ionizing radiation (IR) is used in radiotherapy as a treatment to destroy cancer. Such treatment also affects other tissues, resulting in the so-called normal tissue complications. Endothelial cells (ECs) composing the microvasculature have essential roles in the microenvironment's homeostasis (ME). Thus, detrimental effects induced by irradiation on ECs can influence both the tumor and healthy tissue. In-vitro models can be advantageous to study these phenomena. In this systematic review, we analyzed in-vitro models of ECs subjected to IR. We highlighted the critical issues involved in the production, irradiation, and analysis of such radiobiological in-vitro models to study microvascular endothelial cells damage. For each step, we analyzed common methodologies and critical points required to obtain a reliable model. We identified the generation of a 3D environment for model production and the inclusion of heterogeneous cell populations for a reliable ME recapitulation. Additionally, we highlighted how essential information on the irradiation scheme, crucial to correlate better observed in vitro effects to the clinical scenario, are often neglected in the analyzed studies, limiting the translation of achieved results.
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Huang J, Li JJ. Multiple Dynamics in Tumor Microenvironment Under Radiotherapy. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1263:175-202. [PMID: 32588328 DOI: 10.1007/978-3-030-44518-8_10] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The tumor microenvironment (TME) is an evolutionally low-level and embryonically featured tissue comprising heterogenic populations of malignant and stromal cells as well as noncellular components. Under radiotherapy (RT), the major modality for the treatment of malignant diseases [1], TME shows an adaptive response in multiple aspects that affect the efficacy of RT. With the potential clinical benefits, interests in RT combined with immunotherapy (IT) are intensified with a large scale of clinical trials underway for an array of cancer types. A better understanding of the multiple molecular aspects, especially the cross talks of RT-mediated energy reprogramming and immunoregulation in the irradiated TME (ITME), will be necessary for further enhancing the benefit of RT-IT modality. Coming studies should further reveal more mechanistic insights of radiation-induced instant or permanent consequence in tumor and stromal cells. Results from these studies will help to identify critical molecular pathways including cancer stem cell repopulation, metabolic rewiring, and specific communication between radioresistant cancer cells and the infiltrated immune active lymphocytes. In this chapter, we will focus on the following aspects: radiation-repopulated cancer stem cells (CSCs), hypoxia and re-oxygenation, reprogramming metabolism, and radiation-induced immune regulation, in which we summarize the current literature to illustrate an integrated image of the ITME. We hope that the contents in this chapter will be informative for physicians and translational researchers in cancer radiotherapy or immunotherapy.
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Affiliation(s)
- Jie Huang
- Department of Radiation Oncology, University of California Davis, Sacramento, CA, USA
| | - Jian Jian Li
- Department of Radiation Oncology, University of California Davis, Sacramento, CA, USA. .,NCI-Designated Comprehensive Cancer Center, University of California Davis, Sacramento, CA, USA.
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Cell repopulation, rewiring metabolism, and immune regulation in cancer radiotherapy. RADIATION MEDICINE AND PROTECTION 2020. [DOI: 10.1016/j.radmp.2020.02.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
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Xie B, Wang S, Jiang N, Li JJ. Cyclin B1/CDK1-regulated mitochondrial bioenergetics in cell cycle progression and tumor resistance. Cancer Lett 2018; 443:56-66. [PMID: 30481564 DOI: 10.1016/j.canlet.2018.11.019] [Citation(s) in RCA: 109] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2018] [Revised: 10/27/2018] [Accepted: 11/11/2018] [Indexed: 02/08/2023]
Abstract
A mammalian cell houses two genomes located separately in the nucleus and mitochondria. During evolution, communications and adaptations between these two genomes occur extensively to achieve and sustain homeostasis for cellular functions and regeneration. Mitochondria provide the major cellular energy and contribute to gene regulation in the nucleus, whereas more than 98% of mitochondrial proteins are encoded by the nuclear genome. Such two-way signaling traffic presents an orchestrated dynamic between energy metabolism and consumption in cells. Recent reports have elucidated the way how mitochondrial bioenergetics synchronizes with the energy consumption for cell cycle progression mediated by cyclin B1/CDK1 as the communicator. This review is to recapitulate cyclin B1/CDK1 mediated mitochondrial activities in cell cycle progression and stress response as well as its potential link to reprogram energy metabolism in tumor adaptive resistance. Cyclin B1/CDK1-mediated mitochondrial bioenergetics is applied as an example to show how mitochondria could timely sense the cellular fuel demand and then coordinate ATP output. Such nucleus-mitochondria oscillation may play key roles in the flexible bioenergetics required for tumor cell survival and compromising the efficacy of anti-cancer therapy. Further deciphering the cyclin B1/CDK1-controlled mitochondrial metabolism may invent effect targets to treat resistant cancers.
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Affiliation(s)
- Bowen Xie
- Department of Radiation Oncology, School of Medicine, University of California at Davis, Sacramento, CA, USA
| | - Shuangyan Wang
- Department of Radiation Oncology, School of Medicine, University of California at Davis, Sacramento, CA, USA
| | - Nian Jiang
- Department of Radiation Oncology, School of Medicine, University of California at Davis, Sacramento, CA, USA
| | - Jian Jian Li
- Department of Radiation Oncology, School of Medicine, University of California at Davis, Sacramento, CA, USA.
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Nantajit D, Jetawattana S, Suriyo T, Grdina DJ, Satayavivad J. Andrographis paniculata Diterpenoids Protect against Radiation-Induced Transformation in BALB/3T3 Cells. Radiat Res 2017; 188:66-74. [DOI: 10.1667/rr14698.1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Danupon Nantajit
- Department of Radiation Oncology, Chulabhorn Hospital, Bangkok, Thailand
| | - Suwimol Jetawattana
- Academic Service Unit, Thailand Institute of Nuclear Technology (Public Organization), Nakhon Nayok, Thailand
| | - Tawit Suriyo
- Laboratory of Pharmacology, Chulabhorn Research Institute, Bangkok, Thailand
| | - David J. Grdina
- Department of Radiation and Cellular Oncology, The University of Chicago, Chicago, Illinois
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Kheradmand A, Nayebi AM, Jorjani M, Khalifeh S, Haddadi R. Effects of WR1065 on 6-hydroxydopamine-induced motor imbalance: Possible involvement of oxidative stress and inflammatory cytokines. Neurosci Lett 2016; 627:7-12. [DOI: 10.1016/j.neulet.2016.05.040] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2015] [Revised: 05/14/2016] [Accepted: 05/20/2016] [Indexed: 01/04/2023]
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Kheradmand A, Nayebi AM, Jorjani M, Haddadi R. Effect of WR-1065 on 6-hydroxydopamine-induced catalepsy and IL-6 level in rats. IRANIAN JOURNAL OF BASIC MEDICAL SCIENCES 2016; 19:490-496. [PMID: 27403255 PMCID: PMC4923469] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/13/2015] [Accepted: 12/24/2015] [Indexed: 06/06/2023]
Abstract
OBJECTIVES Neuroinflammation and oxidative stress play a key role in pathogenesis of Parkinson's disease (PD). In the present study we investigated the effect of reactive oxygen species (ROS) scavenger WR-1065 on catalepsy and cerebrospinal fluid (CSF) level of interleukin 6(IL-6) and striatum superoxide dismutase (SOD) activity in 6-hydroxydopamine (6-OHDA) induced experimental model of PD. MATERIALS AND METHODS Seventy two male Wistar rats were divided into 9 equal groups and 6-OHDA (8 μg/2 μl/rat) was infused unilaterally into substantia nigra pars copmacta (SNc) to induce PD. Catalepsy was measured by standard bar test, CSF level of IL-6 was assessed by enzyme-linked immunosorbent assay (ELISA) method and SOD activity measured by spectrophotometric method. In pre-treatment groups WR-1065 (20, 40 and 80 μg/2 μl/rat/day, for 3 days) was infused into the SNc before 6-OHDA administration and 21 days later, as a recovery period, behavioral and molecular assay tests were done. RESULTS Our results showed that pre-treatment with WR-1065 improved (P<0.001) 6-OHDA-induced catalepsy in a dose dependent manner. In 6-OHDA-lesioned animals SOD activity in SNc and CSF level of IL-6 was decreased markedly (P<0.001) when compared with non-lesioned group, while pre-treatment with WR-1065(P<0.001) restored their levels up to the normal range. CONCLUSION Our study indicated that pre-treatment with WR-1065 could modulate catalepsy and IL-6 level in 6-OHDA-lesioned rats. Also WR1065 could increase SOD activity up to normal range. It can be regarded as an anti-oxidative drug in prevention or adjunctive therapy of PD.
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Affiliation(s)
- Afshin Kheradmand
- Drug Applied Research Center, Department of Pharmacology and Toxicology, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Alireza Mohajjel Nayebi
- Drug Applied Research Center, Department of Pharmacology and Toxicology, Tabriz University of Medical Sciences, Tabriz, Iran
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Masoumeh Jorjani
- Department of Pharmacology and Neurobiology Research Center, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Rasool Haddadi
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Hamadan University of Medical Sciences, Hamadan, Iran
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Olivero OA, Ongele MO, Braun HM, Marrogi A, Divi K, Mitchell JB, Poirier MC. Selective protection of zidovudine-induced DNA-damage by the antioxidants WR-1065 and tempol. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2014; 55:566-572. [PMID: 24833597 PMCID: PMC7673230 DOI: 10.1002/em.21872] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2014] [Revised: 04/03/2014] [Accepted: 04/23/2014] [Indexed: 06/03/2023]
Abstract
The cytokinesis-block micronucleus cytome (CBMN) assay, introduced by Fenech, was used to demonstrate different types of DNA damage in MOLT-3 human lymphoblastoid cells exposed to 10 μM zidovudine (AZT). In addition, we explored the cytoprotective potential of two antioxidants, WR-1065 and Tempol, to decrease AZT-induced genotoxicity. Binucleated cells, arrested by Cytochalasin B (Cyt B), were evaluated for micronuclei (MN), caused by DNA damage or chromosomal loss, and chromatin nucleoplasmic bridges (NPBs), caused by telomere attrition. Additionally, nuclear buds (NBUDs), caused by amplified DNA, and apoptotic and necrotic (A/N) cells were scored. We hypothesized that AZT exposure would increase the frequency of genotoxic end points, and that the antioxidants Tempol and WR-1065 would protect against AZT-induced genotoxicity. MOLT-3 cells were exposed to 0 or 10 µM AZT for a total of 76 hr. After the first 24 hr, 0 or 5 µM WR-1065 and/or 0 or 200 µM Tempol were added for the remainder of the experiment. For the last 28 hr (of 76 hr), Cyt B was added to arrest replication after one cell division, leaving a predominance of binucleated cells. The nuclear division index (NDI) was similar for all treatment groups, indicating that the exposures did not alter cell viability. MOLT-3 cells exposed to AZT alone had significant (P < 0.05) increases in MN and NBs, compared to unexposed cells. Both Tempol and WR-1065 protected against AZT-induced MN formation (P < 0.003 for both), and WR-1065, but not Tempol, reduced the levels of A/N (P = 0.041). In cells exposed to AZT/Tempol there were significantly reduced levels of NBUDs, compared to cells exposed to AZT alone (P = 0.015). Cells exposed to AZT/WR-1065 showed reduced levels of NPBs, compared to cells exposed to AZT alone (P = 0.037). Thus WR-1065 and Tempol protected MOLT-3 cells against specific types of AZT-induced DNA damage.
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Affiliation(s)
- Ofelia A. Olivero
- Carcinogen–DNA Interactions Section, Laboratory of Cancer Biology and Genetics, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - Michael O. Ongele
- Carcinogen–DNA Interactions Section, Laboratory of Cancer Biology and Genetics, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - Hannan M. Braun
- Carcinogen–DNA Interactions Section, Laboratory of Cancer Biology and Genetics, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - Ariadna Marrogi
- Carcinogen–DNA Interactions Section, Laboratory of Cancer Biology and Genetics, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - Kathyiani Divi
- Carcinogen–DNA Interactions Section, Laboratory of Cancer Biology and Genetics, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - James B. Mitchell
- Tumor Biology Section, Radiation Biology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - Miriam C. Poirier
- Carcinogen–DNA Interactions Section, Laboratory of Cancer Biology and Genetics, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
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Zhang Y, Martin SG. Redox proteins and radiotherapy. Clin Oncol (R Coll Radiol) 2014; 26:289-300. [PMID: 24581945 DOI: 10.1016/j.clon.2014.02.003] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2013] [Revised: 01/28/2014] [Accepted: 02/07/2014] [Indexed: 01/05/2023]
Abstract
Although conventional radiotherapy can directly damage DNA and other organic molecules within cells, most of the damage and the cytotoxicity of such ionising radiation, comes from the production of ions and free radicals produced via interactions with water. This 'indirect effect', a form of oxidative stress, can be modulated by a variety of systems within cells that are in place to, in normal situations, maintain homeostasis and redox balance. If cancer cells express high levels of antioxidant redox proteins, they may be more resistant to radiation and so targeting such systems may be a profitable strategy to increase therapeutic efficacy of conventional radiotherapy. An overview, with exemplars, of the main systems regulating redox homeostasis is supplied and discussed in relation to their use as prognostic and predictive biomarkers, and how targeting such proteins and systems may increase radiosensitivity and, potentially, improve the radiotherapeutic response.
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Affiliation(s)
- Y Zhang
- Academic Unit of Clinical Oncology, University of Nottingham, School of Medicine, Nottingham University Hospitals NHS Trust, City Hospital Campus, Nottingham, UK
| | - S G Martin
- Academic Unit of Clinical Oncology, University of Nottingham, School of Medicine, Nottingham University Hospitals NHS Trust, City Hospital Campus, Nottingham, UK.
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Noaparast Z, Hosseinimehr SJ. Radioprotective agents for the prevention of side effects induced by radioiodine-131 therapy. Future Oncol 2013; 9:1145-59. [DOI: 10.2217/fon.13.79] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Radioiodine 131 (131I) has been used worldwide for the ablation of remnant thyroidal tissue after surgery or as the first-line treatment for Graves’ disease. Although the use of 131I is becoming increasingly prevalent, there is evidence suggesting that this treatment is associated with side effects such as salivary gland dysfunction and an increased risk of leukemia. This article aims to review the potential use of radioprotective agents and the side effects induced by 131I therapy. Several synthetic and natural compounds have been investigated in preclinical and clinical studies. The protective agents reduced the toxicity of 131I, mainly in the salivary glands, and mitigated the genetic damage through different mechanisms. There are limited clinical studies evaluating the use of radioprotective agents in patients undergoing radioiodine therapy. However, lemon candies, lemon juice and sugarless chewing gum have been proposed to be beneficial for minimizing the side effects of radioiodine within the salivary glands.
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Affiliation(s)
- Zohreh Noaparast
- Department of Radiopharmacy, Faculty of Pharmacy, Pharmaceutical Research Center, Mazandaran University of Medical Sciences, Sari, Iran
| | - Seyed Jalal Hosseinimehr
- Department of Radiopharmacy, Faculty of Pharmacy, Pharmaceutical Research Center, Mazandaran University of Medical Sciences, Sari, Iran.
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Grdina DJ, Murley JS, Miller RC, Mauceri HJ, Sutton HG, Li JJ, Woloschak GE, Weichselbaum RR. A survivin-associated adaptive response in radiation therapy. Cancer Res 2013; 73:4418-28. [PMID: 23651635 DOI: 10.1158/0008-5472.can-12-4640] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Adaptive responses can be induced in cells by very low doses of ionizing radiation resulting in an enhanced resistance to much larger exposures. The inhibitor of apoptosis protein, survivin, has been implicated in many adaptive responses to cellular stress. Computerized axial tomography used in image-guided radiotherapy to position and monitor tumor response uses very low radiation doses ranging from 0.5 to 100 mGy. We investigated the ability of these very low radiation doses administered along with two 2 Gy doses separated by 24 hours, a standard conventional radiotherapy dosing schedule, to initiate adaptive responses resulting in the elevation of radiation resistance in exposed cells. Human colon carcinoma (RKO36), mouse sarcoma (SA-NH), along with transformed mouse embryo fibroblasts, wild type or cells lacking functional tumor necrosis factor receptors 1 and 2 were used to assess their relative ability to express an adaptive response when grown either to confluence in vitro or as tumors in the flank of C57BL/6 mice. The survival of each of these cells was elevated from 5% to 20% (P ≤ 0.05) as compared to cells not receiving a 100 mGy or lesser dose. In addition, the cells exposed to 100 mGy exhibited elevations in survivin levels, reductions in apoptosis frequencies, and loss of an adaptive response if transfected with survivin siRNA. This survivin-mediated adaptive response has the potential for affecting outcomes if regularly induced throughout a course of image guided radiation therapy.
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Affiliation(s)
- David J Grdina
- Department of Radiation and Cellular Oncology, The University of Chicago, Chicago, IL 60637, USA.
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Grdina DJ, Murley JS, Miller RC, Mauceri HJ, Sutton HG, Thirman MJ, Li JJ, Woloschak GE, Weichselbaum RR. A manganese superoxide dismutase (SOD2)-mediated adaptive response. Radiat Res 2012; 179:115-24. [PMID: 23237540 DOI: 10.1667/rr3126.2] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Very low doses of ionizing radiation, 5 to 100 mGy, can induce adaptive responses characterized by elevation in cell survival and reduction in micronuclei formation. Utilizing these end points, RKO human colon carcinoma and transformed mouse embryo fibroblasts (MEF), wild-type or knockout cells missing TNF receptors 1 and 2 (TNFR1(-)R2(-)), and C57BL/6 and TNFR1(-)R2(-) knockout mice, we demonstrate that intact TNF signaling is required for induction of elevated manganese superoxide dismutase (SOD2) activity (P < 0.001) and the subsequent expression of these SOD2-mediated adaptive responses when cells are challenged at a later time with 2 Gy. In contrast, amifostine's free thiol form WR1065 can directly activate NF-κB giving rise to elevated SOD2 activity 24 h later and induce an adaptive response in both MEF wild-type and TNF signaling defective TNFR1(-)R2(-) cells. Transfection of cells with SOD2 siRNA completely abolishes both the elevation in SOD2 activity and expression of the adaptive responses. These results were confirmed in vivo using a micronucleus assay in splenocytes derived from C57BL/6 and TNFR1(-)R2(-) knockout mice that were exposed to 100 mGy or 400 mg/kg amifostine 24 h prior to exposure to a 2 Gy whole-body dose. A dose of 100 mGy also conferred enhanced protection to C57BL/6 mice exposed 24 h later to 100 mg/kg of N-Ethyl-N-nitrosourea (ENU). While very low radiation doses require an intact TNF signaling process to induce a SOD2-mediated adaptive response, amifostine can induce a similar adaptive response in both TNF receptor competent and knockout cells, respectively.
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Affiliation(s)
- David J Grdina
- Department of Radiation and Cellular Oncology, The University of Chicago, Chicago, IL 60637, USA.
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Candas D, Fan M, Nantajit D, Vaughan AT, Murley JS, Woloschak GE, Grdina DJ, Li JJ. CyclinB1/Cdk1 phosphorylates mitochondrial antioxidant MnSOD in cell adaptive response to radiation stress. J Mol Cell Biol 2012; 5:166-75. [PMID: 23243068 DOI: 10.1093/jmcb/mjs062] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Manganese superoxide dismutase (MnSOD), a major antioxidant enzyme within the mitochondria, is responsible for the detoxification of free radicals generated by cellular metabolism and environmental/therapeutic irradiation. Cell cycle-dependent kinase Cdk1, along with its regulatory partner CyclinB1, plays important roles in the regulation of cell cycle progression as well as in genotoxic stress response. Herein, we identified the presence of the minimal Cdk1 phosphorylation consensus sequence ([S/T]-P; Ser106) in human MnSOD, suggesting Cdk1 as a potential upstream kinase of MnSOD. A substantial amount of CyclinB1/Cdk1 was found to localize in the mitochondrion upon irradiation. The enhanced Cdk1/MnSOD interaction and MnSOD phosphorylation were detected in both the irradiated human cells and mouse tissues. We report that CyclinB1/Cdk1 can regulate MnSOD through reversible Ser106 phosphorylation, both in vivo and in vitro. The CyclinB1/Cdk1-mediated MnSOD Ser106 resulted in increased MnSOD activity and stability, along with improved mitochondrial function and cellular resistance to radiation-induced apoptosis. These results demonstrate a unique pro-survival mechanism by which cells enhance the survival via CyclinB1/Cdk1-mediated MnSOD activation under genotoxic stress conditions.
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Affiliation(s)
- Demet Candas
- Department of Radiation Oncology, University of California at Davis, Sacramento, CA 95817, USA
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Eldridge A, Fan M, Woloschak G, Grdina DJ, Chromy BA, Li JJ. Manganese superoxide dismutase interacts with a large scale of cellular and mitochondrial proteins in low-dose radiation-induced adaptive radioprotection. Free Radic Biol Med 2012; 53:1838-47. [PMID: 23000060 PMCID: PMC3494792 DOI: 10.1016/j.freeradbiomed.2012.08.589] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2012] [Revised: 08/24/2012] [Accepted: 08/28/2012] [Indexed: 11/18/2022]
Abstract
The cellular adaptive response to certain low-level genotoxic stresses, including exposure to low-dose ionizing radiation (LDIR), shows promise as a tool to enhance radioprotection in normal cells but not in tumor cells. Manganese superoxide dismutase (MnSOD), a fundamental mitochondrial antioxidant in mammalian cells, plays a key role in the LDIR-induced adaptive response. In this study, we aimed to elucidate the signaling network associated with MnSOD-induced radiation protection. A MnSOD-interacting protein profile was established in LDIR-treated human skin cells. Human skin keratinocytes (HK18) were irradiated with a single dose of LDIR (10 cGy X-ray) and the cell lysates were immunoprecipitated using α-MnSOD and applied to two different gel-based proteomic experiments followed by mass spectrometry for protein identification. Analysis of the profiles of MnSOD-interacting partners before and after LDIR detected various patterns of MnSOD protein-protein interactions in response to LDIR. Interestingly, many of the MnSOD-interacting proteins are known to have functions related to mitochondrial regulation of cell metabolism, apoptosis, and DNA repair. These results provide evidence indicating that in addition to the enzymatic action of detoxifying superoxide, the antioxidant MnSOD may function as a signaling regulator in stress-induced adaptive protection through cell survival pathways.
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Affiliation(s)
- Angela Eldridge
- Department of Radiation Oncology, University of California at Davis School of Medicine, Sacramento, CA 95817, USA
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16
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Stewart FA, Akleyev AV, Hauer-Jensen M, Hendry JH, Kleiman NJ, Macvittie TJ, Aleman BM, Edgar AB, Mabuchi K, Muirhead CR, Shore RE, Wallace WH. ICRP publication 118: ICRP statement on tissue reactions and early and late effects of radiation in normal tissues and organs--threshold doses for tissue reactions in a radiation protection context. Ann ICRP 2012; 41:1-322. [PMID: 22925378 DOI: 10.1016/j.icrp.2012.02.001] [Citation(s) in RCA: 771] [Impact Index Per Article: 64.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
This report provides a review of early and late effects of radiation in normal tissues and organs with respect to radiation protection. It was instigated following a recommendation in Publication 103 (ICRP, 2007), and it provides updated estimates of 'practical' threshold doses for tissue injury defined at the level of 1% incidence. Estimates are given for morbidity and mortality endpoints in all organ systems following acute, fractionated, or chronic exposure. The organ systems comprise the haematopoietic, immune, reproductive, circulatory, respiratory, musculoskeletal, endocrine, and nervous systems; the digestive and urinary tracts; the skin; and the eye. Particular attention is paid to circulatory disease and cataracts because of recent evidence of higher incidences of injury than expected after lower doses; hence, threshold doses appear to be lower than previously considered. This is largely because of the increasing incidences with increasing times after exposure. In the context of protection, it is the threshold doses for very long follow-up times that are the most relevant for workers and the public; for example, the atomic bomb survivors with 40-50years of follow-up. Radiotherapy data generally apply for shorter follow-up times because of competing causes of death in cancer patients, and hence the risks of radiation-induced circulatory disease at those earlier times are lower. A variety of biological response modifiers have been used to help reduce late reactions in many tissues. These include antioxidants, radical scavengers, inhibitors of apoptosis, anti-inflammatory drugs, angiotensin-converting enzyme inhibitors, growth factors, and cytokines. In many cases, these give dose modification factors of 1.1-1.2, and in a few cases 1.5-2, indicating the potential for increasing threshold doses in known exposure cases. In contrast, there are agents that enhance radiation responses, notably other cytotoxic agents such as antimetabolites, alkylating agents, anti-angiogenic drugs, and antibiotics, as well as genetic and comorbidity factors. Most tissues show a sparing effect of dose fractionation, so that total doses for a given endpoint are higher if the dose is fractionated rather than when given as a single dose. However, for reactions manifesting very late after low total doses, particularly for cataracts and circulatory disease, it appears that the rate of dose delivery does not modify the low incidence. This implies that the injury in these cases and at these low dose levels is caused by single-hit irreparable-type events. For these two tissues, a threshold dose of 0.5Gy is proposed herein for practical purposes, irrespective of the rate of dose delivery, and future studies may elucidate this judgement further.
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Murley J, Baker K, Miller R, Darga T, Weichselbaum R, Grdina D. SOD2-mediated adaptive responses induced by low-dose ionizing radiation via TNF signaling and amifostine. Free Radic Biol Med 2011; 51:1918-25. [PMID: 21945096 PMCID: PMC3200566 DOI: 10.1016/j.freeradbiomed.2011.08.032] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2011] [Revised: 08/22/2011] [Accepted: 08/29/2011] [Indexed: 01/27/2023]
Abstract
Manganese superoxide dismutase (SOD2)-mediated adaptive processes that protect against radiation-induced micronucleus formation can be induced in cells after a 2-Gy exposure by previously exposing them to either low-dose ionizing radiation (10cGy) or WR1065 (40μM), the active thiol form of amifostine. Although both adaptive processes culminate in elevated levels of SOD2 enzymatic activity, the underlying pathways differ in complexity, with the tumor necrosis factor α (TNFα) signaling pathway implicated in the low-dose radiation-induced response, but not in the thiol-induced pathway. The goal of this study was the characterization of the effects of TNFα receptors 1 and 2 (TNFR1, TNFR2) on the adaptive responses induced by low-dose irradiation or thiol exposure using micronucleus formation as an endpoint. BFS-1 wild-type cells with functional TNFR1 and 2 were exposed 24h before a 2-Gy dose of ionizing radiation to either 10cGy or a 40μM dose of WR1065. BFS2C-SH02 cells, defective in TNFR1, and BFS2C-SH22 cells, defective in both TNFR1 and TNFR2 and generated from BFS2C-SH02 cells by transfection with a murine TNFR2-targeting vector and confirmed to be TNFR2 defective by quantitative PCR, were also exposed under similar conditions for comparison. A 10-cGy dose of radiation induced a significant elevation in SOD2 activity in BFS-1 (P<0.001) and BFS2C-SH02 (P=0.005) but not BFS2C-SH22 cells (P=0.433), compared to their respective untreated controls. In contrast, WR1065 significantly induced elevations in SOD2 activity in all three cell lines (P=0.001, P=0.007, P=0.020, respectively). A significant reduction in the frequency of radiation-induced micronuclei was observed in each cell line when exposure to a 2-Gy challenge dose of radiation occurred during the period of maximal elevation in SOD2 activity. However, this adaptive effect was completely inhibited if the cells were transfected 24h before low-dose radiation or thiol exposure with SOD2 siRNA. Under the conditions tested, TNFR1 and 2 inhibition negatively affected the low-dose radiation-induced but not the thiol-induced adaptive responses observed to be mediated by elevations in SOD2 activity.
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MESH Headings
- Amifostine/analogs & derivatives
- Amifostine/chemistry
- Animals
- Cell Line, Tumor
- Enzyme Activation/genetics
- Enzyme Activation/radiation effects
- Mercaptoethylamines/chemistry
- Mercaptoethylamines/pharmacology
- Mice
- Micronuclei, Chromosome-Defective/drug effects
- Micronuclei, Chromosome-Defective/radiation effects
- Micronucleus Tests
- RNA, Small Interfering/genetics
- Radiation, Ionizing
- Receptors, Tumor Necrosis Factor, Type I/genetics
- Receptors, Tumor Necrosis Factor, Type I/metabolism
- Receptors, Tumor Necrosis Factor, Type II/genetics
- Receptors, Tumor Necrosis Factor, Type II/metabolism
- Signal Transduction/drug effects
- Signal Transduction/genetics
- Signal Transduction/radiation effects
- Superoxide Dismutase/genetics
- Superoxide Dismutase/metabolism
- Tumor Necrosis Factor-alpha/pharmacology
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Affiliation(s)
- J.S. Murley
- Department of Radiation and Cellular Oncology, The University of Chicago, 5841 S. Maryland Avenue, Chicago, Illinois, U.S.A. 60637
| | - K.L. Baker
- Department of Radiation and Cellular Oncology, The University of Chicago, 5841 S. Maryland Avenue, Chicago, Illinois, U.S.A. 60637
| | - R.C. Miller
- Department of Radiation and Cellular Oncology, The University of Chicago, 5841 S. Maryland Avenue, Chicago, Illinois, U.S.A. 60637
| | - T.E. Darga
- Department of Radiation and Cellular Oncology, The University of Chicago, 5841 S. Maryland Avenue, Chicago, Illinois, U.S.A. 60637
| | - R.R. Weichselbaum
- Department of Radiation and Cellular Oncology, The University of Chicago, 5841 S. Maryland Avenue, Chicago, Illinois, U.S.A. 60637
| | - D.J. Grdina
- Department of Radiation and Cellular Oncology, The University of Chicago, 5841 S. Maryland Avenue, Chicago, Illinois, U.S.A. 60637
- Corresponding Author. 773-702-5250 (phone); 773-702-5740 (fax);
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18
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Lee TK, O'Brien KF, Wang W, Johnke RM, Sheng C, Benhabib SM, Wang T, Allison RR. Radioprotective effect of American ginseng on human lymphocytes at 90 minutes postirradiation: a study of 40 cases. J Altern Complement Med 2011; 16:561-7. [PMID: 20491513 DOI: 10.1089/acm.2009.0590] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Ionizing radiation (IR) initiates intracellular oxidative stress through enhanced formation of reactive oxygen species (ROS) that attack DNA leading to cell death. Because of the diversity of IR applied in medicine, agriculture, industry, and the growing threats of global terrorism, the acquisition of radioprotectors is an urgent need for the nation. However, the applicability of radioprotectors currently under investigation is limited due to their inherent toxicity. OBJECTIVE This study investigated the effect of a standardized North American ginseng extract (NAGE, total ginsenoside content: 11.7%) on DNA damage in human lymphocytes at 90 minutes postirradiation. DESIGN With the application of NAGE (250-1000 microg mL(-1)) at 90 minutes postirradiation (1 and 2 Gy), DNA damage in lymphocytes obtained from 40 healthy individuals was evaluated by cytokinesis-block micronucleus assay. Similar experiments were also performed in lymphocytes treated with WR-1065 (1 mmol/L or 3 mmol/L). In addition, before and after irradiation, lymphocytes obtained from 10 individuals were measured for their total antioxidant capacity (TAC) and the reactive oxygen species (ROS). RESULTS The significant effect of NAGE against (137)Cs-induced micronuclei (MN) in lymphocytes is concentration dependent. NAGE (750 microg mL(-1)) reduced MN yield by 50.7% after 1 Gy and 35.9% after 2 Gy exposures, respectively; these results were comparable to that of WR-1065. Furthermore, we also found that NAGE reduces MN yield and ROS but increases TAC in lymphocytes. CONCLUSIONS Our results suggest that NAGE is a relatively nontoxic natural compound that holds radioprotective potential in human lymphocytes even when applied at 90 minutes postirradiation. One of the radioprotective mechanisms may be mediated through the scavenging of free radicals and enhancement of the intracellular TAC.
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Affiliation(s)
- Tung-Kwang Lee
- Department of Radiation Oncology, Leo W. Jenkins Cancer Center, Brody School of Medicine at East Carolina University, Greenville, NC, USA.
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19
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Roche M, Kemp FW, Agrawal A, Attanasio A, Neti PVSV, Howell RW, Ferraris RP. Marked changes in endogenous antioxidant expression precede vitamin A-, C-, and E-protectable, radiation-induced reductions in small intestinal nutrient transport. Free Radic Biol Med 2011; 50:55-65. [PMID: 20970494 PMCID: PMC3014460 DOI: 10.1016/j.freeradbiomed.2010.10.689] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2010] [Revised: 09/20/2010] [Accepted: 10/11/2010] [Indexed: 11/18/2022]
Abstract
Rapidly proliferating epithelial crypt cells of the small intestine are susceptible to radiation-induced oxidative stress, yet there is a dearth of data linking this stress to expression of antioxidant enzymes and to alterations in intestinal nutrient absorption. We previously showed that 5-14 days after acute γ-irradiation, intestinal sugar absorption decreased without change in antioxidant enzyme expression. In the present study, we measured antioxidant mRNA and protein expression in mouse intestines taken at early times postirradiation. Observed changes in antioxidant expression are characterized by a rapid decrease within 1h postirradiation, followed by dramatic upregulation within 4h and then downregulation a few days later. The cell type and location expressing the greatest changes in levels of the oxidative stress marker 4HNE and of antioxidant enzymes are, respectively, epithelial cells responsible for nutrient absorption and the crypt region comprising mainly undifferentiated cells. Consumption of a cocktail of antioxidant vitamins A, C, and E, before irradiation, prevents reductions in transport of intestinal sugars, amino acids, bile acids, and peptides. Ingestion of antioxidants may blunt radiation-induced decreases in nutrient transport, perhaps by reducing acute oxidative stress in crypt cells, thereby allowing the small intestine to retain its absorptive function when those cells migrate to the villus days after the insult.
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Affiliation(s)
- Marjolaine Roche
- Department of Pharmacology and Physiology, New Jersey Medical School, University of Medicine & Dentistry of New Jersey, Newark, NJ, USA
| | - Francis W Kemp
- Department of Preventive Medicine & Community Health, New Jersey Medical School, University of Medicine & Dentistry of New Jersey, Newark, NJ, USA
| | - Amit Agrawal
- Department of Pharmacology and Physiology, New Jersey Medical School, University of Medicine & Dentistry of New Jersey, Newark, NJ, USA
| | - Alicia Attanasio
- Department of Pharmacology and Physiology, New Jersey Medical School, University of Medicine & Dentistry of New Jersey, Newark, NJ, USA
| | - Prasad VSV Neti
- Department of Radiology, New Jersey Medical School Cancer Center, University of Medicine & Dentistry of New Jersey, Newark, NJ, USA
| | - Roger W Howell
- Department of Radiology, New Jersey Medical School Cancer Center, University of Medicine & Dentistry of New Jersey, Newark, NJ, USA
| | - Ronaldo P Ferraris
- Department of Pharmacology and Physiology, New Jersey Medical School, University of Medicine & Dentistry of New Jersey, Newark, NJ, USA
- Corresponding Author, Ronaldo P. Ferraris, Ph.D., Department of Pharmacology & Physiology, MSB H621, UMDNJ New Jersey Medical School, 185 S. Orange Ave., Newark, NJ 07103, 973-972-4519,
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20
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Murley JS, Kataoka Y, Miller RC, Li JJ, Woloschak G, Grdina DJ. SOD2-mediated effects induced by WR1065 and low-dose ionizing radiation on micronucleus formation in RKO human colon carcinoma cells. Radiat Res 2010; 175:57-65. [PMID: 21175348 DOI: 10.1667/rr2349.1] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
RKO36 cells exposed to either WR1065 or 10 cGy X rays show elevated SOD2 gene expression and SOD2 enzymatic activity. Cells challenged at this time with 2 Gy exhibit enhanced radiation resistance. This phenomenon has been identified as a delayed radioprotective effect or an adaptive response when induced by thiols or low-dose radiation, respectively. In this study we investigated the relative effectiveness of both WR1065 and low-dose radiation in reducing the incidence of radiation-induced micronucleus formation in binucleated RKO36 human colon carcinoma cells. The role of SOD2 in this process was assessed by measuring changes in enzymatic activity as a function of the inducing agent used, the level of protection afforded, and the inhibitory effects of short interfering RNA (SOD2 siRNA). Both WR1065 and 10 cGy X rays effectively induced a greater than threefold elevation in SOD2 activity 24 h after exposure. Cells irradiated at this time with 2 Gy exhibited a significant resistance to micronucleus formation (P < 0.05; Student's two-tailed t test). This protective effect was significantly inhibited in cells transfected with SOD2 siRNA. SOD2 played an important role in the adaptive/delayed radioprotective response by inhibiting the initiation of a superoxide anion-induced ROS cascade leading to enhanced mitochondrial and nuclear damages.
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Affiliation(s)
- Jeffrey S Murley
- Department of Radiation and Cellular Oncology, The University of Chicago, Chicago, Illinois 60637, USA
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21
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Dziegielewski J, Goetz W, Murley JS, Grdina DJ, Morgan WF, Baulch JE. Amifostine metabolite WR-1065 disrupts homologous recombination in mammalian cells. Radiat Res 2010; 173:175-83. [PMID: 20095849 DOI: 10.1667/rr1982.1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Repair of DNA damage through homologous recombination (HR) pathways plays a crucial role in maintaining genome stability. However, overstimulation of HR pathways in response to genotoxic stress may abnormally elevate recombination frequencies, leading to increased mutation rates and delayed genomic instability. Radiation-induced genomic instability has been detected after exposure to both low- and high-linear energy transfer (LET) radiations, but the mechanisms responsible for initiating or propagating genomic instability are not known. We have demonstrated that WR-1065, the active metabolite of amifostine, protects against radiation-induced cell killing and delayed genomic instability. We hypothesize that hyperstimulation of HR pathways plays a mechanistic role in radiation-induced genomic instability and that, in part, WR-1065 exerts it radioprotective effect through suppression of the HR pathway. Results of this study demonstrate that WR-1065 treatment selectively protected against radiation-induced cell killing in HR-proficient cell lines compared to an HR-deficient cell line. Further, WR-1065 treatment decreases HR in response to DNA damage using two different mammalian cell systems. This suppression of hyper-recombination is a previously unrecognized mechanism by which WR-1065 effects radioprotection in mammalian cells.
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Affiliation(s)
- Jaroslaw Dziegielewski
- Department of Radiation Oncology, Radiation Oncology Research Laboratory, University of Maryland School of Medicine, Baltimore, Maryland, USA
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22
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Grdina DJ, Murley JS, Kataoka Y, Baker KL, Kunnavakkam R, Coleman MC, Spitz DR. Amifostine induces antioxidant enzymatic activities in normal tissues and a transplantable tumor that can affect radiation response. Int J Radiat Oncol Biol Phys 2009; 73:886-96. [PMID: 19215822 DOI: 10.1016/j.ijrobp.2008.10.061] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2008] [Revised: 10/03/2008] [Accepted: 10/08/2008] [Indexed: 01/24/2023]
Abstract
PURPOSE To determine whether amifostine can induce elevated manganese superoxide dismutase (SOD2) in murine tissues and a transplantable SA-NH tumor, resulting in a delayed tumor cell radioprotective effect. METHODS AND MATERIALS SA-NH tumor-bearing C3H mice were treated with a single 400 mg/kg or three daily 50 mg/kg doses of amifostine administered intraperitoneally. At selected time intervals after the last injection, the heart, liver, lung, pancreas, small intestine, spleen, and SA-NH tumor were removed and analyzed for SOD2, catalase, and glutathione peroxidase (GPx) enzymatic activity. The effect of elevated SOD2 enzymatic activity on the radiation response of SA-NH cells was determined. RESULTS SOD2 activity was significantly elevated in selected tissues and a tumor 24 h after amifostine treatment. Catalase and GPx activities remained unchanged except for significant elevations in the spleen. GPx was also elevated in the pancreas. SA-NH tumor cells exhibited a twofold elevation in SOD2 activity and a 27% elevation in radiation resistance. Amifostine administered in three daily fractions of 50 mg/kg each also resulted in significant elevations of these antioxidant enzymes. CONCLUSIONS Amifostine can induce a delayed radioprotective effect that correlates with elevated levels of SOD2 activity in SA-NH tumor. If limited to normal tissues, this delayed radioprotective effect offers an additional potential for overall radiation protection. However, amifostine-induced elevation of SOD2 activity in tumors could have an unanticipated deleterious effect on tumor responses to fractionated radiation therapy, given that the radioprotector is administered daily just before each 2-Gy fractionated dose.
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Affiliation(s)
- David J Grdina
- Department of Radiation and Cellular Oncology, The University of Chicago, Chicago, IL 60637, USA.
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23
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Dziegielewski J, Baulch JE, Goetz W, Coleman MC, Spitz DR, Murley JS, Grdina DJ, Morgan WF. WR-1065, the active metabolite of amifostine, mitigates radiation-induced delayed genomic instability. Free Radic Biol Med 2008; 45:1674-81. [PMID: 18845240 PMCID: PMC2629584 DOI: 10.1016/j.freeradbiomed.2008.09.004] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2008] [Revised: 08/14/2008] [Accepted: 09/02/2008] [Indexed: 11/24/2022]
Abstract
Compounds that can protect cells from the effects of radiation are important for clinical use, in the event of an accidental or terrorist-generated radiation event, and for astronauts traveling in space. One of the major concerns regarding the use of radio-protective agents is that they may protect cells initially, but predispose surviving cells to increased genomic instability later. In this study we used WR-1065, the active metabolite of amifostine, to determine how protection from direct effects of high- and low-LET radiation exposure influences genomic stability. When added 30 min before irradiation and in high concentrations, WR-1065 protected cells from immediate radiation-induced effects as well as from delayed genomic instability. Lower, nontoxic concentrations of WR-1065 did not protect cells from death; however, it was effective in significantly decreasing delayed genomic instability in the progeny of irradiated cells. The observed increase in manganese superoxide dismutase protein levels and activity may provide an explanation for this effect. These results confirm that WR-1065 is protective against both low- and high-LET radiation-induced genomic instability in surviving cells.
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Affiliation(s)
- Jaroslaw Dziegielewski
- Department of Radiation Oncology, Radiation Oncology Research Laboratory, University of Maryland School of Medicine, Baltimore, MD, USA
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24
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Mell LK, Movsas B. Pharmacologic normal tissue protection in clinical radiation oncology: focus on amifostine. Expert Opin Drug Metab Toxicol 2008; 4:1341-50. [PMID: 18798703 DOI: 10.1517/17425255.4.10.1341] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND Radiation toxicity is an important problem that limits treatment intensity and adversely affects patients' quality of life. Amifostine is a cytoprotector that can reduce toxicity and potentially improve the therapeutic ratio of radiotherapy. OBJECTIVE To discuss the role of amifostine in modern radiotherapy and compare and contrast with alternative approaches to reducing radiation toxicity. METHODS We conducted a literature search through Medline to identify randomized clinical trials pertaining to keyword 'amifostine'. We also consulted reviews, book chapters and selected articles regarding amifostine and normal tissue protection. RESULTS/CONCLUSION Amifostine is an effective normal tissue protector with level I evidence supporting its use in head and neck and gynecologic cancers but studies in other disease sites, although promising, are inconclusive. Further study is needed to demonstrate conclusively the benefits of wider amifostine use.
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Affiliation(s)
- Loren K Mell
- University of California San Diego, Department of Radiation Oncology, La Jolla, California, USA
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