1
|
O’Leary BR, Kalen AL, Pope AN, Goswami PC, Cullen JJ. Hydrogen Peroxide Mediates Pharmacological Ascorbate Induced Radio-Sensitization of Pancreatic Cancer Cells by Enhancing G2-accumulation and Reducing Cyclin B1 Protein Levels. Radiat Res 2023; 200:444-455. [PMID: 37758045 PMCID: PMC10699322 DOI: 10.1667/rade-22-00182.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Accepted: 08/24/2023] [Indexed: 10/03/2023]
Abstract
Pharmacological ascorbate (P-AscH-, high dose, intravenous vitamin C) preferentially sensitizes human pancreas ductal adenocarcinoma (PDAC) cells to radiation-induced toxicity compared to non-tumorigenic epithelial cells. Radiation-induced G2-checkpoint activation contributes to the resistance of cancer cells to DNA damage induced toxicity. We hypothesized that P-AscH- induced radio-sensitization of PDAC cells is mediated by perturbations in the radiation induced activation of the G2-checkpoint pathway. Both non-tumorigenic pancreatic ductal epithelial and PDAC cells display decreased clonogenic survival and increased doubling times after radiation treatment. In contrast, the addition of P-AscH- to radiation increases clonogenic survival and decreases the doubling time of non-tumorigenic epithelial cells but decreasing clonogenic survival and increasing the doubling time of PDAC cells. Results from the mitotic index and propidium iodide assays showed that while the P-AscH- treatments did not affect radiation-induced G2-checkpoint activation, it enhanced G2-accumulation. The addition of catalase reverses the increases in G2-accumulation, indicating a peroxide-mediated mechanism. In addition, P-AscH- treatment of PDAC cells suppresses radiation-induced accumulation of cyclin B1 protein levels. Both translational and post-translational pathways appear to regulate cyclin B1 protein levels after the combination treatment of PDAC cells with P-AscH- and radiation. The protein changes seen are reversed by the addition of catalase suggesting that hydrogen peroxide mediates P-AscH- induced radiation sensitization of PDAC cells by enhancing G2-accumulation and reducing cyclin B1 protein levels.
Collapse
Affiliation(s)
- Brianne R. O’Leary
- Departments of Surgery and Free Radical and Radiation Biology Division, The University of Iowa Carver College of Medicine, Iowa City, Iowa
| | - Amanda L. Kalen
- Department of Radiation Oncology, The University of Iowa Carver College of Medicine, Iowa City, Iowa
| | - Amanda N. Pope
- Department of Radiation Oncology, The University of Iowa Carver College of Medicine, Iowa City, Iowa
| | - Prabhat C. Goswami
- Department of Radiation Oncology, The University of Iowa Carver College of Medicine, Iowa City, Iowa
| | - Joseph J. Cullen
- Departments of Surgery and Free Radical and Radiation Biology Division, The University of Iowa Carver College of Medicine, Iowa City, Iowa
- Department of Radiation Oncology, The University of Iowa Carver College of Medicine, Iowa City, Iowa
| |
Collapse
|
2
|
Radioresistance in Prostate Cancer: Focus on the Interplay between NF-κB and SOD. Antioxidants (Basel) 2021; 10:antiox10121925. [PMID: 34943029 PMCID: PMC8750009 DOI: 10.3390/antiox10121925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 11/15/2021] [Accepted: 11/22/2021] [Indexed: 11/16/2022] Open
Abstract
Prostate cancer occurs frequently in men and can often lead to death. Many cancers, including prostate cancer, can be initiated by oxidative insult caused by free radicals and reactive oxygen species. The superoxide dismutase family removes the oxygen-derived reactive oxygen species, and increased superoxide dismutase activity can often be protective against prostate cancer. Prostate cancer can be treated in a variety of ways, including surgery, androgen deprivation therapy, radiation therapy, and chemotherapy. The clinical trajectory of prostate cancer varies from patient to patient, but more aggressive tumors often tend to be radioresistant. This is often due to the free-radical and reactive-oxygen-species-neutralizing effects of the superoxide dismutase family. Superoxide dismutase 2, which is especially important in this regard, can be induced by the NF-κB pathway, which is an important mechanism in radioresistance. This information has enabled the development of interventions that manipulate the NF-κB mechanism to treat prostate cancer.
Collapse
|
3
|
Varmazyad M, Modi MM, Kalen AL, Sarsour EH, Wagner B, Du J, Schultz MK, Buettner GR, Pigge FC, Goswami PC. N-alkyl triphenylvinylpyridinium conjugated dihydroartemisinin perturbs mitochondrial functions resulting in enhanced cancer versus normal cell toxicity. Free Radic Biol Med 2021; 165:421-434. [PMID: 33561488 PMCID: PMC8020572 DOI: 10.1016/j.freeradbiomed.2021.01.050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 01/17/2021] [Accepted: 01/28/2021] [Indexed: 10/22/2022]
Abstract
Dihydroartemisinin (DHA) is an FDA-approved antimalarial drug that has been repurposed for cancer therapy because of its preferential antiproliferative effects on cancer versus normal cells. Mitochondria represent an attractive target for cancer therapy based on their regulatory role in proliferation and cell death. This study investigates whether DHA conjugated to innately fluorescent N-alkyl triphenylvinylpyridinium (TPVP) perturbs mitochondrial functions resulting in a differential toxicity of cancer versus normal cells. TPVP-DHA treatments resulted in a dose-dependent toxicity of human melanoma and pancreatic cancer cells, whereas normal human fibroblasts were resistant to this treatment. TPVP-DHA treatments resulted in a G1-delay of the cancer cell cycle, which was also associated with a significant inhibition of the mTOR-metabolic and ERK1/2-proliferative signaling pathways. TPVP-DHA treatments perturbed mitochondrial functions, which correlated with increases in mitochondrial fission. In summary, TPVP mediated mitochondrial targeting of DHA enhanced cancer cell toxicity by perturbing mitochondrial functions and morphology.
Collapse
Affiliation(s)
| | - Mira M Modi
- Basic Science Department, College of Osteopathic Medicine, Kansas City University, Kansas City, MO, 64106, USA
| | - Amanda L Kalen
- Free Radical and Radiation Biology Division, Department of Radiation Oncology, University of Iowa, Iowa City, IA, 52242, USA
| | - Ehab H Sarsour
- Basic Science Department, College of Osteopathic Medicine, Kansas City University, Kansas City, MO, 64106, USA
| | - Brett Wagner
- Free Radical and Radiation Biology Division, Department of Radiation Oncology, University of Iowa, Iowa City, IA, 52242, USA
| | - Juan Du
- Department of Surgery, University of Iowa, Iowa City, IA, 52242, USA
| | - Michael K Schultz
- Department of Radiology, University of Iowa, Iowa City, IA, 52242, USA
| | - Garry R Buettner
- Free Radical and Radiation Biology Division, Department of Radiation Oncology, University of Iowa, Iowa City, IA, 52242, USA
| | | | - Prabhat C Goswami
- Free Radical and Radiation Biology Division, Department of Radiation Oncology, University of Iowa, Iowa City, IA, 52242, USA.
| |
Collapse
|
4
|
McCann E, O'Sullivan J, Marcone S. Targeting cancer-cell mitochondria and metabolism to improve radiotherapy response. Transl Oncol 2021; 14:100905. [PMID: 33069104 PMCID: PMC7562988 DOI: 10.1016/j.tranon.2020.100905] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Accepted: 09/23/2020] [Indexed: 02/07/2023] Open
Abstract
Radiotherapy is a regimen that uses ionising radiation (IR) to treat cancer. Despite the availability of several therapeutic options, cancer remains difficult to treat and only a minor percentage of patients receiving radiotherapy show a complete response to the treatment due to development of resistance to IR (radioresistance). Therefore, radioresistance is a major clinical problem and is defined as an adaptive response of the tumour to radiation-induced damage by altering several cellular processes which sustain tumour growth including DNA damage repair, cell cycle arrest, alterations of oncogenes and tumour suppressor genes, autophagy, tumour metabolism and altered reactive oxygen species. Cellular organelles, in particular mitochondria, are key players in mediating the radiation response in tumour, as they regulate many of the cellular processes involved in radioresistance. In this article has been reviewed the recent findings describing the cellular and molecular mechanism by which cancer rewires the function of the mitochondria and cellular metabolism to enhance radioresistance, and the role that drugs targeting cellular bioenergetics have in enhancing radiation response in cancer patients.
Collapse
Affiliation(s)
- Emma McCann
- Department of Surgery, Trinity Translational Medicine Institute, St. James's Hospital, Trinity College Dublin, Dublin, Ireland; M.Sc. in Translational Oncology, Trinity College Dublin, Dublin, Ireland
| | - Jacintha O'Sullivan
- Department of Surgery, Trinity Translational Medicine Institute, St. James's Hospital, Trinity College Dublin, Dublin, Ireland
| | - Simone Marcone
- Department of Surgery, Trinity Translational Medicine Institute, St. James's Hospital, Trinity College Dublin, Dublin, Ireland.
| |
Collapse
|
5
|
Brand MD. Riding the tiger - physiological and pathological effects of superoxide and hydrogen peroxide generated in the mitochondrial matrix. Crit Rev Biochem Mol Biol 2020; 55:592-661. [PMID: 33148057 DOI: 10.1080/10409238.2020.1828258] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Elevated mitochondrial matrix superoxide and/or hydrogen peroxide concentrations drive a wide range of physiological responses and pathologies. Concentrations of superoxide and hydrogen peroxide in the mitochondrial matrix are set mainly by rates of production, the activities of superoxide dismutase-2 (SOD2) and peroxiredoxin-3 (PRDX3), and by diffusion of hydrogen peroxide to the cytosol. These considerations can be used to generate criteria for assessing whether changes in matrix superoxide or hydrogen peroxide are both necessary and sufficient to drive redox signaling and pathology: is a phenotype affected by suppressing superoxide and hydrogen peroxide production; by manipulating the levels of SOD2, PRDX3 or mitochondria-targeted catalase; and by adding mitochondria-targeted SOD/catalase mimetics or mitochondria-targeted antioxidants? Is the pathology associated with variants in SOD2 and PRDX3 genes? Filtering the large literature on mitochondrial redox signaling using these criteria highlights considerable evidence that mitochondrial superoxide and hydrogen peroxide drive physiological responses involved in cellular stress management, including apoptosis, autophagy, propagation of endoplasmic reticulum stress, cellular senescence, HIF1α signaling, and immune responses. They also affect cell proliferation, migration, differentiation, and the cell cycle. Filtering the huge literature on pathologies highlights strong experimental evidence that 30-40 pathologies may be driven by mitochondrial matrix superoxide or hydrogen peroxide. These can be grouped into overlapping and interacting categories: metabolic, cardiovascular, inflammatory, and neurological diseases; cancer; ischemia/reperfusion injury; aging and its diseases; external insults, and genetic diseases. Understanding the involvement of mitochondrial matrix superoxide and hydrogen peroxide concentrations in these diseases can facilitate the rational development of appropriate therapies.
Collapse
|
6
|
Gibson AR, O'Leary BR, Du J, Sarsour EH, Kalen AL, Wagner BA, Stolwijk JM, Falls-Hubert KC, Alexander MS, Carroll RS, Spitz DR, Buettner GR, Goswami PC, Cullen JJ. Dual Oxidase-Induced Sustained Generation of Hydrogen Peroxide Contributes to Pharmacologic Ascorbate-Induced Cytotoxicity. Cancer Res 2020; 80:1401-1413. [PMID: 32041838 PMCID: PMC7127976 DOI: 10.1158/0008-5472.can-19-3094] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Revised: 12/23/2019] [Accepted: 01/31/2020] [Indexed: 01/24/2023]
Abstract
Pharmacologic ascorbate treatment (P-AscH-, high-dose, intravenous vitamin C) results in a transient short-term increase in the flux of hydrogen peroxide that is preferentially cytotoxic to cancer cells versus normal cells. This study examines whether an increase in hydrogen peroxide is sustained posttreatment and potential mechanisms involved in this process. Cellular bioenergetic profiling following treatment with P-AscH- was examined in tumorigenic and nontumorigenic cells. P-AscH- resulted in sustained increases in the rate of cellular oxygen consumption (OCR) and reactive oxygen species (ROS) in tumor cells, with no changes in nontumorigenic cells. Sources for this increase in ROS and OCR were DUOX 1 and 2, which are silenced in pancreatic ductal adenocarcinoma, but upregulated with P-AscH- treatment. An inducible catalase system, to test causality for the role of hydrogen peroxide, reversed the P-AscH--induced increases in DUOX, whereas DUOX inhibition partially rescued P-AscH--induced toxicity. In addition, DUOX was significantly downregulated in pancreatic cancer specimens compared with normal pancreas tissues. Together, these results suggest that P-AscH--induced toxicity may be enhanced by late metabolic shifts in tumor cells, resulting in a feed-forward mechanism for generation of hydrogen peroxide and induction of metabolic stress through enhanced DUOX expression and rate of oxygen consumption. SIGNIFICANCE: A high dose of vitamin C, in addition to delivering an acute exposure of H2O2 to tumor cells, activates DUOX in pancreatic cancer cells, which provide sustained production of H2O2.
Collapse
Affiliation(s)
- Adrienne R Gibson
- Free Radical and Radiation Biology Division, Department of Radiation Oncology, The University of Iowa Carver College of Medicine, Iowa City, Iowa
| | - Brianne R O'Leary
- Free Radical and Radiation Biology Division, Department of Surgery, The University of Iowa Carver College of Medicine, Iowa City, Iowa
| | - Juan Du
- Free Radical and Radiation Biology Division, Department of Surgery, The University of Iowa Carver College of Medicine, Iowa City, Iowa
| | - Ehab H Sarsour
- Kansas City University of Medicine and Biosciences, Kansas City, Missouri
| | - Amanda L Kalen
- Free Radical and Radiation Biology Division, Department of Radiation Oncology, The University of Iowa Carver College of Medicine, Iowa City, Iowa
| | - Brett A Wagner
- Free Radical and Radiation Biology Division, Department of Radiation Oncology, The University of Iowa Carver College of Medicine, Iowa City, Iowa
| | - Jeffrey M Stolwijk
- Free Radical and Radiation Biology Division, Department of Radiation Oncology, The University of Iowa Carver College of Medicine, Iowa City, Iowa
| | - Kelly C Falls-Hubert
- Free Radical and Radiation Biology Division, Department of Radiation Oncology, The University of Iowa Carver College of Medicine, Iowa City, Iowa
| | - Matthew S Alexander
- Free Radical and Radiation Biology Division, Department of Surgery, The University of Iowa Carver College of Medicine, Iowa City, Iowa
| | - Rory S Carroll
- Free Radical and Radiation Biology Division, Department of Surgery, The University of Iowa Carver College of Medicine, Iowa City, Iowa
| | - Douglas R Spitz
- Free Radical and Radiation Biology Division, Department of Radiation Oncology, The University of Iowa Carver College of Medicine, Iowa City, Iowa
| | - Garry R Buettner
- Free Radical and Radiation Biology Division, Department of Radiation Oncology, The University of Iowa Carver College of Medicine, Iowa City, Iowa
| | - Prabhat C Goswami
- Free Radical and Radiation Biology Division, Department of Radiation Oncology, The University of Iowa Carver College of Medicine, Iowa City, Iowa
| | - Joseph J Cullen
- Free Radical and Radiation Biology Division, Department of Radiation Oncology, The University of Iowa Carver College of Medicine, Iowa City, Iowa.
- Free Radical and Radiation Biology Division, Department of Surgery, The University of Iowa Carver College of Medicine, Iowa City, Iowa
| |
Collapse
|
7
|
Hydrogen Peroxide Mediates Artemisinin-Derived C-16 Carba-Dimer-Induced Toxicity of Human Cancer Cells. Antioxidants (Basel) 2020; 9:antiox9020108. [PMID: 31991904 PMCID: PMC7070254 DOI: 10.3390/antiox9020108] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Revised: 01/17/2020] [Accepted: 01/24/2020] [Indexed: 11/17/2022] Open
Abstract
This study used a nitroaliphatic chemistry approach to synthesize a novel artemisinin-derived carba-dimer (AG-1) and determined its anti-proliferative effects in human normal and cancer cells. AG-1 treatments selectively inhibit proliferation of cancer cells compared to normal human fibroblasts. Compared to artemisinin, AG-1 is more toxic to human breast, prostate, head–neck, pancreas and skin cancer cells; 50% inhibition (IC50) 123 µM in AG-1 vs. 290 µM in artemisinin-treated breast cancer cells. AG-1 treatment decreased (~5 folds) cyclin D1 protein expression that correlated with an increase in the percentage of cells in the G1-phase, suggesting a G1 delay. AG-1-induced toxicity was independent of the DNA damage at 72 h post-treatment, as measured by micronuclei frequency and γH2AX protein levels. Results from electron paramagnetic resonance spectroscopy showed Fe-catalyzed formation of AG-1 carbon-centered radicals in a cell-free system. Flow cytometry analysis of H2DCF-DA oxidation showed a significant increase in the steady-state levels of reactive oxygen species (ROS) in AG-1-treated cells. Pre-treatment with N-acetyl-l-cysteine and antioxidant enzymes (superoxide dismutase and catalase) significantly suppressed AG-1-induced toxicity, suggesting that superoxide and hydrogen peroxide contribute to AG-1-induced toxicity in human cancer cells. AG-1 represents a novel class of anti-cancer drug that is more potent than its parent compound, artemisinin.
Collapse
|
8
|
Lafin JT, Sarsour EH, Kalen AL, Wagner BA, Buettner GR, Goswami PC. Methylseleninic Acid Induces Lipid Peroxidation and Radiation Sensitivity in Head and Neck Cancer Cells. Int J Mol Sci 2019; 20:ijms20010225. [PMID: 30626124 PMCID: PMC6337472 DOI: 10.3390/ijms20010225] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2018] [Revised: 12/17/2018] [Accepted: 01/04/2019] [Indexed: 12/20/2022] Open
Abstract
Combination radiation and chemotherapy are commonly used to treat locoregionally advanced head and neck squamous cell carcinoma (HNSCC). Aggressive dosing of these therapies is significantly hampered by side effects due to normal tissue toxicity. Selenium represents an adjuvant that selectively sensitizes cancer cells to these treatments modalities, potentially by inducing lipid peroxidation (LPO). This study investigated whether one such selenium compound, methylseleninic acid (MSA), induces LPO and radiation sensitivity in HNSCC cells. Results from 4,4-difluoro-4-bora-3a,4a-diaza-S-indacene (BODIPY) C11 oxidation and ferric thiocyanate assays revealed that MSA induced LPO in cells rapidly and persistently. Propidium iodide (PI) exclusion assay found that MSA was more toxic to cancer cells than other related selenium compounds; this toxicity was abrogated by treatment with α-tocopherol, an LPO inhibitor. MSA exhibited no toxicity to normal fibroblasts at similar doses. MSA also sensitized HNSCC cells to radiation as determined by clonogenic assay. Intracellular glutathione in cancer cells was depleted following MSA treatment, and supplementation of the intracellular glutathione pool with N-acetylcysteine sensitized cells to MSA. The addition of MSA to a cell-free solution of glutathione resulted in an increase in oxygen consumption, which was abrogated by catalase, suggesting the formation of H2O2. Results from this study identify MSA as an inducer of LPO, and reveal its capability to sensitize HNSCC to radiation. MSA may represent a potent adjuvant to radiation therapy in HNSCC.
Collapse
Affiliation(s)
- John T Lafin
- Department of Urology, University of Texas Southwestern Medical Center, Dallas, TX 75235, USA.
| | - Ehab H Sarsour
- The University of Iowa Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa, Iowa City, IA 52242, USA.
| | - Amanda L Kalen
- The University of Iowa Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa, Iowa City, IA 52242, USA.
| | - Brett A Wagner
- The University of Iowa Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa, Iowa City, IA 52242, USA.
| | - Garry R Buettner
- The University of Iowa Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa, Iowa City, IA 52242, USA.
| | - Prabhat C Goswami
- The University of Iowa Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa, Iowa City, IA 52242, USA.
| |
Collapse
|
9
|
Kalen AL, Ahmad IM, Abdalla MY, O'Malley YQ, Goswami PC, Sarsour EH. MnSOD and Cyclin B1 Coordinate a Mito-Checkpoint during Cell Cycle Response to Oxidative Stress. Antioxidants (Basel) 2017; 6:E92. [PMID: 29149089 PMCID: PMC5745502 DOI: 10.3390/antiox6040092] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Revised: 11/08/2017] [Accepted: 11/14/2017] [Indexed: 11/22/2022] Open
Abstract
Communication between the nucleus and mitochondrion could coordinate many cellular processes. While the mechanisms regulating this communication are not completely understood, we hypothesize that cell cycle checkpoint proteins coordinate the cross-talk between nuclear and mitochondrial functions following oxidative stress. Human normal skin fibroblasts, representative of the G₂-phase, were irradiated with 6 Gy of ionizing radiation and assayed for cyclin B1 translocation, mitochondrial function, reactive oxygen species (ROS) levels, and cytotoxicity. In un-irradiated controls, cyclin B1 was found primarily in the nucleus of G₂-cells. However, following irradiation, cyclin B1 was excluded from the nucleus and translocated to the cytoplasm and mitochondria. These observations were confirmed further by performing transmission electron microscopy and cell fractionation assays. Cyclin B1 was absent in mitochondria isolated from un-irradiated G₂-cells and present in irradiated G₂-cells. Radiation-induced translocation of cyclin B1 from the nucleus to the mitochondrion preceded changes in the activities of mitochondrial proteins, that included decreases in the activities of aconitase and the mitochondrial antioxidant enzyme, manganese superoxide dismutase (MnSOD), and increases in complex II activity. Changes in the activities of mito-proteins were followed by an increase in dihydroethidium (DHE) oxidation (indicative of increased superoxide levels) and loss of the mitochondrial membrane potential, events that preceded the restart of the stalled cell cycle and subsequently the loss in cell viability. Comparable results were also observed in un-irradiated control cells overexpressing mitochondria-targeted cyclin B1. These results indicate that MnSOD and cyclin B1 coordinate a cross-talk between nuclear and mitochondrial functions, to regulate a mito-checkpoint during the cell cycle response to oxidative stress.
Collapse
Affiliation(s)
- Amanda L Kalen
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa, Iowa City, IA 52242, USA.
| | - Iman M Ahmad
- Department of Medical Imaging and Therapeutic Sciences, College of Allied Health Professions, University of Nebraska Medical Center, Omaha, NE 68198, USA.
| | - Maher Y Abdalla
- Department of Pathology and Microbiology, College of Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA.
| | - Yunxia Q O'Malley
- Department of Pediatrics, University of Iowa, Iowa City, IA 52242, USA.
| | - Prabhat C Goswami
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa, Iowa City, IA 52242, USA.
| | - Ehab H Sarsour
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa, Iowa City, IA 52242, USA.
| |
Collapse
|
10
|
Fu TY, Tsai MH, Wang JS, Ger LP. Antioxidant enzymes in oral verrucous carcinoma. J Oral Pathol Med 2016; 46:46-49. [PMID: 27245640 DOI: 10.1111/jop.12460] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/01/2016] [Indexed: 11/30/2022]
Abstract
BACKGROUND Verrucous carcinoma is a non-metastasizing variant of welldifferentiated squamous cell carcinoma, which has been associated with reactive oxygen species generated by betel quid chewing. Salivary antioxidant systems have been suggested to play a protective role in reducing the oxidative damage. Herein, we investigated the difference of the enzymatic antioxidant system expressions in oral verrucous carcinoma and oral squamous cell carcinoma. METHODS The enzymatic antioxidant system expressions, including manganese superoxide dismutase, glutathione peroxidase, and catalase were evaluated by immunohistochemistry in a series of 202 surgically resected oral squamous cell carcinoma and 20 oral verrucous carcinoma specimens, using tissue microarray slides. RESULTS The immuno-staining intensities of superoxide dismutase and glutathione peroxidase were strongest in the oral squamous cell carcinoma group than in verrucous carcinoma. The catalase expression showed no difference between different pathological groups. CONCLUSIONS The different degrees of superoxide dismutase and glutathione expressions in verrucous carcinoma and squamous cell carcinoma may be helpful for pathologists to differentiate these two entities, especially between oral verrucous carcinoma and well differentiated oral squamous cell carcinoma.
Collapse
Affiliation(s)
- Ting-Ying Fu
- Department of Pathology and Laboratory Medicine, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan.,Yuh-Ing Junior College of Health Care & Management, Kaohsiung, Taiwan
| | - Meng-Han Tsai
- Department of Neurology, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan.,Department of Nursing, Meiho University, Pingtung, Taiwan
| | - Jyh-Seng Wang
- Department of Pathology and Laboratory Medicine, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
| | - Luo-Ping Ger
- Department of Biological Sciences, National Sun Yat-Sen University, Kaohsiung, Taiwan.,Department of Medical Education and Research, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
| |
Collapse
|
11
|
Todorović A, Pejić S, Stojiljković V, Gavrilović L, Popović N, Pavlović I, Saičić ZS, Pajović SB. Antioxidative enzymes in irradiated rat brain-indicators of different regional radiosensitivity. Childs Nerv Syst 2015; 31:2249-56. [PMID: 26143278 DOI: 10.1007/s00381-015-2807-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/03/2014] [Accepted: 06/23/2015] [Indexed: 12/01/2022]
Abstract
PURPOSE Previously, we examined manganese superoxide dismutase (MnSOD), copper-zinc superoxide dismutase (CuZnSOD), and catalase (CAT) activities in rat brain irradiated with 2 or 3 Gy of γ-rays. The results indicated that lower MnSOD activity and inducibility found in hippocampus might explain higher radiosensitivity of this brain region. Thus, in this study, we wanted to determine changes of MnSOD, CuZnSOD, and CAT activities after dose of 5 Gy and to find out if differences in MnSOD activity are caused by changes in its expression. METHODS Heads of 4-day-old female rats were irradiated with γ-rays, using (60)Co. Animals were sacrificed 1/24 h after exposure. Hippocampus and cortex tissues were prepared for enzyme activity measurements and Western blot analysis. RESULTS One hour after exposure, γ-rays significantly decreased MnSOD activity in both examined brain regions. Twenty-four hours later, MnSOD recovery showed dose and regional dependence. It was weaker at higher doses and in hippocampal region. MnSOD expression changed in the similar manner as MnSOD activity only at lower doses of γ-rays. In both examined brain regions, gamma radiation significantly decreased CuZnSOD activity and did not change activity of CAT. CONCLUSIONS Our results confirmed that MnSOD plays an important role in different regional radiosensitivity but also showed that depending on dose, radiation affects MnSOD level by utterly different mechanisms. Postradiation changes of CuZnSOD and CAT are not regionally specific and therefore, cannot account for the different radiosensitivity of the hippocampus and cortex.
Collapse
Affiliation(s)
- Ana Todorović
- Laboratory of Molecular Biology and Endocrinology, Vinča Institute of Nuclear Sciences, University of Belgrade, PO Box 522, 11001, Belgrade, Serbia.
| | - Snežana Pejić
- Laboratory of Molecular Biology and Endocrinology, Vinča Institute of Nuclear Sciences, University of Belgrade, PO Box 522, 11001, Belgrade, Serbia
| | - Vesna Stojiljković
- Laboratory of Molecular Biology and Endocrinology, Vinča Institute of Nuclear Sciences, University of Belgrade, PO Box 522, 11001, Belgrade, Serbia
| | - Ljubica Gavrilović
- Laboratory of Molecular Biology and Endocrinology, Vinča Institute of Nuclear Sciences, University of Belgrade, PO Box 522, 11001, Belgrade, Serbia
| | - Nataša Popović
- Laboratory of Molecular Biology and Endocrinology, Vinča Institute of Nuclear Sciences, University of Belgrade, PO Box 522, 11001, Belgrade, Serbia
| | - Ivan Pavlović
- Laboratory of Molecular Biology and Endocrinology, Vinča Institute of Nuclear Sciences, University of Belgrade, PO Box 522, 11001, Belgrade, Serbia
| | - Zorica S Saičić
- Department of Physiology, Institute for Biological Research "Siniša Stanković", University of Belgrade, 11060, Belgrade, Serbia
| | - Snežana B Pajović
- Laboratory of Molecular Biology and Endocrinology, Vinča Institute of Nuclear Sciences, University of Belgrade, PO Box 522, 11001, Belgrade, Serbia
| |
Collapse
|
12
|
Rybakova YS, Kalen AL, Eckers JC, Fedorova TN, Goswami PC, Sarsour EH. [Increased manganese superoxide dismutase and cyclin B1 expression in carnosine-induced inhibition of glioblastoma cell proliferation]. BIOMEDIT︠S︡INSKAI︠A︡ KHIMII︠A︡ 2015; 61:510-8. [PMID: 26350743 DOI: 10.18097/pbmc20156104510] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Carnosine is an endogenous dipeptide with antiproliferative properties. Here we show that carnosine selectively inhibits proliferation of human glioblastoma cells (U-118-MG) compared to breast (MB231) and oral (Cal27 and FaDu) cancer cells. Carnosine-induced inhibition of U-118-MG proliferation is associated with a significant: decrease in cellular reactive oxygen species levels, increase in manganese superoxide dismutase (MnSOD) and increase in cyclin B1 expression resulting in G2-block. We conclude that the antiproliferative property of carnosine is due to its ability to enhance MnSOD and cyclin B1 expression. These results will be of significance to the potential application of carnosine in brain cancer therapy.
Collapse
Affiliation(s)
| | - A L Kalen
- Free Radical and Radiation Biology Division, Department of Radiation Oncology, University of Iowa, Iowa City, USA
| | - J C Eckers
- Free Radical and Radiation Biology Division, Department of Radiation Oncology, University of Iowa, Iowa City, USA
| | | | - P C Goswami
- Free Radical and Radiation Biology Division, Department of Radiation Oncology, University of Iowa, Iowa City, USA
| | - E H Sarsour
- Free Radical and Radiation Biology Division, Department of Radiation Oncology, University of Iowa, Iowa City, USA
| |
Collapse
|
13
|
Rybakova YS, Kalen AL, Eckers JC, Fedorova TN, Goswami PC, Sarsour EH. Increased manganese superoxide dismutase and cyclin B1 expression in carnosine-induced inhibition of glioblastoma cell proliferation. BIOCHEMISTRY MOSCOW-SUPPLEMENT SERIES B-BIOMEDICAL CHEMISTRY 2015. [DOI: 10.1134/s1990750815010096] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
14
|
Fetisova EK, Antoschina MM, Cherepanynets VD, Izumov DS, Kireev II, Kireev RI, Lyamzaev KG, Riabchenko NI, Chernyak BV, Skulachev VP. Radioprotective effects of mitochondria-targeted antioxidant SkQR1. Radiat Res 2014; 183:64-71. [PMID: 25496313 DOI: 10.1667/rr13708.1] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
We show here that mitochondria-targeted antioxidant composed of plastoquinone conjugated through hydrocarbon linker with cationic rhodamine 19 (SkQR1) protected against nuclear DNA damage induced by gamma radiation in K562 erythroleukemia cells. We also demonstrate that SkQR1 prevented the early (1 h postirradiation) accumulation of phosphorylated histone H2AX (γ-H2AX) an indicator of DNA double-strand break formation, as well as the radiation-induced increase in chromosomal aberrations. These data suggested that nuclear DNA damage induced by gamma radiation may be mediated by mitochondrial reactive oxygen species (ROS) production. We show that SkQR1 suppressed delayed accumulation of ROS 32 h after irradiation probably by inhibiting mitochondrial ROS-induced ROS release mechanisms. This suggests that mitochondria-targeted antioxidants may protect cells from the late consequences of radiation exposure related to delayed oxidative stress. We have previously reported that SkQRl is the substrate of multidrug resistance pump P-glycoproten (Pgp 170) and selectively protects Pgp 170-negative cells against oxidative stress. In line with this finding, we demonstrate here that SkQR1 did not protect Pgp170-positive K562 subline against DNA damage induced by gamma radiation. The selective radioprotection of normal Pgp 170-negative cells by mitochondria-targeted antioxidants could be a promising strategy to increase the efficiency of radiotherapy for multidrug-resistant tumors.
Collapse
Affiliation(s)
- Elena K Fetisova
- a Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Vorobyevy Gory 1, Moscow 119991, Russia
| | | | | | | | | | | | | | | | | | | |
Collapse
|
15
|
Eckers JC, Kalen AL, Sarsour EH, Tompkins VS, Janz S, Son JM, Doskey CM, Buettner GR, Goswami PC. Forkhead box M1 regulates quiescence-associated radioresistance of human head and neck squamous carcinoma cells. Radiat Res 2014; 182:420-9. [PMID: 25229973 DOI: 10.1667/rr13726.1] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Cellular quiescence is a reversible growth arrest in which cells retain their ability to enter into and exit from the proliferative cycle. This study investigates the hypothesis that cell growth-state specific oxidative stress response regulates radiosensitivity of cancer cells. Results showed that quiescent (low proliferative index; >75% G1 phase and lower RNA content) Cal27 and FaDu human head and neck squamous cell carcinoma (HNSCC) are radioresistant compared to proliferating cells. Quiescent cells exhibited a three to tenfold increase in mRNA levels of Mn-superoxide dismutase (MnSOD), dual oxidase 2 (DUOX2) and dual-specificity phosphatase 1 (DUSP1), while mRNA levels of catalase (CAT), peroxiredoxin 3 (PRDX3) and C-C motif ligand 5 (CCL5) were approximately two to threefold lower compared to proliferating cells. mRNA levels of forkhead box M1 (FOXM1) showed the largest decrease in quiescent cells at approximately 18-fold. Surprisingly, radiation treatment resulted in a distinct gene expression pattern that is specific to proliferating and quiescent cells. Specifically, FOXM1 expression increased two to threefold in irradiated quiescent cells, while the same treatment had no net effect on FOXM1 mRNA expression in proliferating cells. RNA interference and pharmacological-based downregulation of FOXM1 abrogated radioresistance of quiescent cells. Furthermore, radioresistance of quiescent cells was associated with an increase in glucose consumption and expression of glucose-6-phosphate dehydrogenase (G6PD). Knockdown of FOXM1 resulted in a significant decrease in G6PD expression, and pharmacological-inhibition of G6PD sensitized quiescent cells to radiation. Taken together, these results suggest that targeting FOXM1 may overcome radioresistance of quiescent HNSCC.
Collapse
Affiliation(s)
- Jaimee C Eckers
- a Free Radical and Radiation Biology Division, Department of Radiation Oncology
| | | | | | | | | | | | | | | | | |
Collapse
|
16
|
Sarsour EH, Kalen AL, Goswami PC. Manganese superoxide dismutase regulates a redox cycle within the cell cycle. Antioxid Redox Signal 2014; 20:1618-27. [PMID: 23590434 PMCID: PMC3942678 DOI: 10.1089/ars.2013.5303] [Citation(s) in RCA: 75] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
SIGNIFICANCE Manganese superoxide dismutase (MnSOD) is a nuclear-encoded and mitochondria-matrix-localized oxidation-reduction (redox) enzyme that regulates cellular redox homeostasis. Cellular redox processes are known to regulate proliferative and quiescent growth states. Therefore, MnSOD and mitochondria-generated reactive oxygen species (ROS) are believed to be critical regulators of quiescent cells' entry into the cell cycle and exit from the proliferative cycle back to the quiescent state. RECENT ADVANCES/CRITICAL ISSUES Recent evidence suggests that the intracellular redox environment fluctuates during the cell cycle, shifting toward a more oxidized status during mitosis. MnSOD activity is higher in G0/G1 cells compared with S, G2 and M phases. After cell division, MnSOD activity increases in the G1 phase of the daughter generation. The periodic fluctuation in MnSOD activity during the cell cycle inversely correlates with cellular superoxide levels as well as glucose and oxygen consumption. Based on an inverse correlation between MnSOD activity and glucose consumption during the cell cycle, it is proposed that MnSOD is a central molecular player for the "Warburg effect." FUTURE DIRECTIONS In general, loss of MnSOD activity results in aberrant proliferation. A better understanding of the MnSOD and mitochondrial ROS-dependent cell cycle processes may lead to novel approaches to overcome aberrant proliferation. Since ROS have both deleterious (pathological) and beneficial (physiological) effects, it is proposed that "eustress" should be used when discussing ROS processes that regulate normal physiological functions, while "oxidative stress" should be used to discuss the deleterious effects of ROS.
Collapse
Affiliation(s)
- Ehab H Sarsour
- Free Radical and Radiation Biology Division, Department of Radiation Oncology, University of Iowa , Iowa City, Iowa
| | | | | |
Collapse
|
17
|
Holley AK, Miao L, St Clair DK, St Clair WH. Redox-modulated phenomena and radiation therapy: the central role of superoxide dismutases. Antioxid Redox Signal 2014; 20:1567-89. [PMID: 24094070 PMCID: PMC3942704 DOI: 10.1089/ars.2012.5000] [Citation(s) in RCA: 90] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
SIGNIFICANCE Ionizing radiation is a vital component in the oncologist's arsenal for the treatment of cancer. Approximately 50% of all cancer patients will receive some form of radiation therapy as part of their treatment regimen. DNA is considered the major cellular target of ionizing radiation and can be damaged directly by radiation or indirectly through reactive oxygen species (ROS) formed from the radiolysis of water, enzyme-mediated ROS production, and ROS resulting from altered aerobic metabolism. RECENT ADVANCES ROS are produced as a byproduct of oxygen metabolism, and superoxide dismutases (SODs) are the chief scavengers. ROS contribute to the radioresponsiveness of normal and tumor tissues, and SODs modulate the radioresponsiveness of tissues, thus affecting the efficacy of radiotherapy. CRITICAL ISSUES Despite its prevalent use, radiation therapy suffers from certain limitations that diminish its effectiveness, including tumor hypoxia and normal tissue damage. Oxygen is important for the stabilization of radiation-induced DNA damage, and tumor hypoxia dramatically decreases radiation efficacy. Therefore, auxiliary therapies are needed to increase the effectiveness of radiation therapy against tumor tissues while minimizing normal tissue injury. FUTURE DIRECTIONS Because of the importance of ROS in the response of normal and cancer tissues to ionizing radiation, methods that differentially modulate the ROS scavenging ability of cells may prove to be an important method to increase the radiation response in cancer tissues and simultaneously mitigate the damaging effects of ionizing radiation on normal tissues. Altering the expression or activity of SODs may prove valuable in maximizing the overall effectiveness of ionizing radiation.
Collapse
Affiliation(s)
- Aaron K Holley
- 1 Graduate Center for Toxicology, University of Kentucky , Lexington, Kentucky
| | | | | | | |
Collapse
|
18
|
Coleman MC, Olivier AK, Jacobus JA, Mapuskar KA, Mao G, Martin SM, Riley DP, Gius D, Spitz DR. Superoxide mediates acute liver injury in irradiated mice lacking sirtuin 3. Antioxid Redox Signal 2014; 20:1423-35. [PMID: 23919724 PMCID: PMC3936509 DOI: 10.1089/ars.2012.5091] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
AIMS This study determined whether acute radiation-induced liver injury seen in Sirtuin3(-/-) mice after exposure to Cs-137 γ-rays was mediated by superoxide anion (O2(•-)). RESULTS Male wild-type (WT) and SIRT3(-/-) mice were given 2×2 Gy whole-body radiation doses separated by 24 h and livers were harvested 20 h after the second dose. Ex vivo measurements in fresh frozen liver sections demonstrated 50% increases in dihydroethidium oxidation from SIRT3(-/-) animals, relative to WT animals, before irradiation, but this increase was not detected 20 h after radiation exposure. In addition, irradiated livers from SIRT3(-/-) animals showed significant hydropic degeneration, loss of MitoTracker Green FM staining, increased immunohistochemical staining for 3-nitrotyrosine, loss of Ki67 staining, and increased mitochondrial localization of p53. These parameters of radiation-induced injury were significantly attenuated by an intraperitoneal injection of 2 mg/kg of the highly specific superoxide dismutase mimic, GC4401, 30 min before each fraction. INNOVATION Sirtuin 3 (SIRT3) is believed to regulate mitochondrial oxidative metabolism and antioxidant defenses in response to acute radiation-induced liver injury. This work provides strong evidence for the causal role of O2(•-) in the liver injury process initiated by whole-body irradiation in SIRT3(-/-) mice. CONCLUSION These results support the hypothesis that O2(•-) mediates acute liver injury in SIRT3(-/-) animals exposed to whole-body γ-radiation and suggest that GC4401 could be used as a radio-protective compound in vivo.
Collapse
Affiliation(s)
- Mitchell C Coleman
- 1 Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, Carver College of Medicine, The University of Iowa , Iowa City, Iowa
| | | | | | | | | | | | | | | | | |
Collapse
|
19
|
Eckers JC, Kalen AL, Xiao W, Sarsour EH, Goswami PC. Selenoprotein P inhibits radiation-induced late reactive oxygen species accumulation and normal cell injury. Int J Radiat Oncol Biol Phys 2013; 87:619-25. [PMID: 24074935 DOI: 10.1016/j.ijrobp.2013.06.2063] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2013] [Revised: 06/18/2013] [Accepted: 06/29/2013] [Indexed: 10/26/2022]
Abstract
PURPOSE Radiation is a common mode of cancer therapy whose outcome is often limited because of normal tissue toxicity. We have shown previously that the accumulation of radiation-induced late reactive oxygen species (ROS) precedes cell death, suggesting that metabolic oxidative stress could regulate cellular radiation response. The purpose of this study was to investigate whether selenoprotein P (SEPP1), a major supplier of selenium to tissues and an antioxidant, regulates late ROS accumulation and toxicity in irradiated normal human fibroblasts (NHFs). METHODS AND MATERIALS Flow cytometry analysis of cell viability, cell cycle phase distribution, and dihydroethidium oxidation, along with clonogenic assays, were used to measure oxidative stress and toxicity. Human antioxidant mechanisms array and quantitative real-time polymerase chain reaction assays were used to measure gene expression during late ROS accumulation in irradiated NHFs. Sodium selenite addition and SEPP1 overexpression were used to determine the causality of SEPP1 regulating late ROS accumulation and toxicity in irradiated NHFs. RESULTS Irradiated NHFs showed late ROS accumulation (4.5-fold increase from control; P<.05) that occurs after activation of the cell cycle checkpoint pathways and precedes cell death. The mRNA levels of CuZn- and Mn-superoxide dismutase, catalase, peroxiredoxin 3, and thioredoxin reductase 1 increased approximately 2- to 3-fold, whereas mRNA levels of cold shock domain containing E1 and SEPP1 increased more than 6-fold (P<.05). The addition of sodium selenite before the radiation treatment suppressed toxicity (45%; P<.05). SEPP1 overexpression suppressed radiation-induced late ROS accumulation (35%; P<.05) and protected NHFs from radiation-induced toxicity (58%; P<.05). CONCLUSION SEPP1 mitigates radiation-induced late ROS accumulation and normal cell injury.
Collapse
Affiliation(s)
- Jaimee C Eckers
- Free Radical and Radiation Biology Division, Department of Radiation Oncology, University of Iowa, Iowa City, Iowa
| | | | | | | | | |
Collapse
|
20
|
Corniola R, Zou Y, Leu D, Fike JR, Huang TT. Paradoxical relationship between Mn superoxide dismutase deficiency and radiation-induced cognitive defects. PLoS One 2012; 7:e49367. [PMID: 23145165 PMCID: PMC3493523 DOI: 10.1371/journal.pone.0049367] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2012] [Accepted: 10/10/2012] [Indexed: 02/04/2023] Open
Abstract
Radiation therapy of the CNS, even at low doses, can lead to deficits in neurocognitive functions. Reduction in hippocampal neurogenesis is usually, but not always, associated with cognitive deficits resulting from radiation therapy. Generation of reactive oxygen species is considered the main cause of radiation-induced tissue injuries, and elevated levels of oxidative stress persist long after the initial cranial irradiation. Consequently, mutant mice with reduced levels of the mitochondrial antioxidant enzyme, Mn superoxide dismutase (MnSOD or Sod2), are expected to be more sensitive to radiation-induced changes in hippocampal neurogenesis and the related functions. In this study, we showed that MnSOD deficiency led to reduced generation of immature neurons in Sod2−/+ mice even though progenitor cell proliferation was not affected. Compared to irradiated Sod2+/+ mice, which showed cognitive defects and reduced differentiation of newborn cells towards the neuronal lineage, irradiated Sod2−/+ mice showed normal hippocampal-dependent cognitive functions and normal differentiation pattern for newborn neurons and astroglia. However, we also observed a disproportional decrease in newborn neurons in irradiated Sod2−/+ following behavioral studies, suggesting that MnSOD deficiency may render newborn neurons more sensitive to stress from behavioral trainings following cranial irradiation. A positive correlation between normal cognitive functions and normal dendritic spine densities in dentate granule cells was observed. The data suggest that maintenance of synaptic connections, via maintenance of dendritic spines, may be important for normal cognitive functions following cranial irradiation.
Collapse
Affiliation(s)
- Rikki Corniola
- Department of Neurology and Neurological Sciences, Stanford University School of Medicine, Stanford, California, United States of America
| | - Yani Zou
- Department of Neurology and Neurological Sciences, Stanford University School of Medicine, Stanford, California, United States of America
| | - David Leu
- Palo Alto Institute for Research and Education, Palo Alto, California, United States of America
- Geriatric Research, Education, and Clinical Center (GRECC), VA Palo Alto Health Care System, Palo Alto, California, United States of America
| | - John R. Fike
- Departments of Neurosurgery and Radiation Oncology, University of California San Francisco, San Francisco, California, United States of America
| | - Ting-Ting Huang
- Department of Neurology and Neurological Sciences, Stanford University School of Medicine, Stanford, California, United States of America
- Geriatric Research, Education, and Clinical Center (GRECC), VA Palo Alto Health Care System, Palo Alto, California, United States of America
- * E-mail:
| |
Collapse
|
21
|
Kumar MG, Patel NM, Nicholson AM, Kalen AL, Sarsour EH, Goswami PC. Reactive oxygen species mediate microRNA-302 regulation of AT-rich interacting domain 4a and C-C motif ligand 5 expression during transitions between quiescence and proliferation. Free Radic Biol Med 2012; 53:974-82. [PMID: 22732186 PMCID: PMC3418417 DOI: 10.1016/j.freeradbiomed.2012.06.019] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/18/2012] [Revised: 06/12/2012] [Accepted: 06/14/2012] [Indexed: 01/17/2023]
Abstract
Normal cell growth consists of two distinct phases, quiescence and proliferation. Quiescence, or G(0), is a reversible growth arrest in which cells retain the ability to reenter the proliferative cycle (G(1), S, G(2), and M). Although not actively dividing, quiescent cells are metabolically active and quiescence is actively maintained. Our results from microRNA PCR arrays and Taqman PCR assays showed a significant decrease (4-fold) in miR-302 levels during quiescence compared to proliferating normal human fibroblasts, suggesting that miR-302 could regulate cellular proliferation. Results from a Q-RT-PCR and dual-luciferase-3'-UTR reporter assays identified ARID4a (AT-rich interacting domain 4a, also known as RBP1) and CCL5 (C-C motif ligand 5) as targets for miR-302. Ionizing radiation decreased miR-302 levels, which was associated with an increase in its target mRNA levels, ARID4a and CCL5. Such an inverse correlation was also observed in cells treated with hydrogen peroxide as well as SOD2-overexpressing cells. Overexpression of miR-302 suppresses ARID4a and CCL5 mRNA levels, and increased the percentage of S-phase cells. These results identified miR-302 as an ROS-sensitive regulator of ARID4a and CCL5 mRNAs as well as demonstrate a regulatory role of miR-302 during quiescence and proliferation.
Collapse
Affiliation(s)
- Maneesh G. Kumar
- Free Radical and Radiation Biology Division, Department of Radiation Oncology, University of Iowa, Iowa City, Iowa, USA
| | - Neil M. Patel
- Free Radical and Radiation Biology Division, Department of Radiation Oncology, University of Iowa, Iowa City, Iowa, USA
| | - Adam M. Nicholson
- Free Radical and Radiation Biology Division, Department of Radiation Oncology, University of Iowa, Iowa City, Iowa, USA
| | - Amanda L. Kalen
- Free Radical and Radiation Biology Division, Department of Radiation Oncology, University of Iowa, Iowa City, Iowa, USA
| | - Ehab H. Sarsour
- Free Radical and Radiation Biology Division, Department of Radiation Oncology, University of Iowa, Iowa City, Iowa, USA
| | - Prabhat C. Goswami
- Free Radical and Radiation Biology Division, Department of Radiation Oncology, University of Iowa, Iowa City, Iowa, USA
| |
Collapse
|
22
|
Sarsour EH, Kalen AL, Xiao Z, Veenstra TD, Chaudhuri L, Venkataraman S, Reigan P, Buettner GR, Goswami PC. Manganese superoxide dismutase regulates a metabolic switch during the mammalian cell cycle. Cancer Res 2012; 72:3807-16. [PMID: 22710435 PMCID: PMC3429130 DOI: 10.1158/0008-5472.can-11-1063] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Proliferating cells consume more glucose to cope with the bioenergetics and biosynthetic demands of rapidly dividing cells as well as to counter a shift in cellular redox environment. This study investigates the hypothesis that manganese superoxide dismutase (MnSOD) regulates cellular redox flux and glucose consumption during the cell cycle. A direct correlation was observed between glucose consumption and percentage of S-phase cells in MnSOD wild-type fibroblasts, which was absent in MnSOD homozygous knockout fibroblasts. Results from electron paramagnetic resonance spectroscopy and flow cytometric assays showed a significant increase in cellular superoxide levels in S-phase cells, which was associated with an increase in glucose and oxygen consumption, and a decrease in MnSOD activity. Mass spectrometry results showed a complex pattern of MnSOD-methylation at both lysine (68, 89, 122, and 202) and arginine (197 and 216) residues. MnSOD protein carrying a K89A mutation had significantly lower activity compared with wild-type MnSOD. Computational-based simulations indicate that lysine and arginine methylation of MnSOD during quiescence would allow greater accessibility to the enzyme active site as well as increase the positive electrostatic potential around and within the active site. Methylation-dependent changes in the MnSOD conformation and subsequent changes in the electrostatic potential around the active site during quiescence versus proliferation could increase the accessibility of superoxide, a negatively charged substrate. These results support the hypothesis that MnSOD regulates a "metabolic switch" during progression from quiescent through the proliferative cycle. We propose MnSOD as a new molecular player contributing to the Warburg effect.
Collapse
Affiliation(s)
- Ehab H. Sarsour
- Free Radical and Radiation Biology Division, Department of Radiation Oncology, University of Iowa, Iowa City, Iowa, USA
| | - Amanda L. Kalen
- Free Radical and Radiation Biology Division, Department of Radiation Oncology, University of Iowa, Iowa City, Iowa, USA
| | - Zhen Xiao
- Laboratory of Proteomics and Analytical Technologies, National Cancer Institute, Frederick, Maryland, USA
| | - Timothy D. Veenstra
- Laboratory of Proteomics and Analytical Technologies, National Cancer Institute, Frederick, Maryland, USA
| | - Leena Chaudhuri
- Division of Hematology and Oncology, Mayo Clinic, Scottsdale, Arizona, USA
| | | | - Philip Reigan
- School of Pharmacy, University of Colorado, Denver, USA
| | - Garry R. Buettner
- Free Radical and Radiation Biology Division, Department of Radiation Oncology, University of Iowa, Iowa City, Iowa, USA
| | - Prabhat C. Goswami
- Free Radical and Radiation Biology Division, Department of Radiation Oncology, University of Iowa, Iowa City, Iowa, USA
| |
Collapse
|
23
|
Caputo F, Vegliante R, Ghibelli L. Redox modulation of the DNA damage response. Biochem Pharmacol 2012; 84:1292-306. [PMID: 22846600 DOI: 10.1016/j.bcp.2012.07.022] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2012] [Revised: 07/18/2012] [Accepted: 07/19/2012] [Indexed: 01/09/2023]
Abstract
Lesions to DNA trigger the DNA-damage response (DDR), a complex, multi-branched cell-intrinsic process targeted to DNA repair, or elimination of the damaged cells by apoptosis. DDR aims at reducing permanence of mutated cells, decreasing the risk of tumor development: the more stringent the response, the lower the likelihood that sub-lethally damaged, unrepaired cells survive and proliferate. Accordingly, leakage often occurs in tumor cells with compromised DDR, accumulating mutations and accelerating tumor progression. Oxidations mediate DNA damage upon different insults such as UV, X and γ radiation, pollutants, poisons, or endogenous disequilibria, producing different types of lesions that trigger DDR, which can be alleviated by antioxidants. But reactive oxygen species (ROS), and the enzymes involved in their production or scavenging, also participate in DDR signaling, modulating the activity of key enzymes, and regulating the stringency of DDR. Accordingly, antioxidant enzymes such as superoxide dismutase play intimate and complex roles in tumor development, exceeding the basal roles of preventing the initial DNA damage. Likewise, it is emerging that dietary antioxidants help controlling tumor onset and progression by preventing DNA damage and by acting on cell cycle checkpoints, opening a novel and promising frontier to anticancer therapy.
Collapse
Affiliation(s)
- Fanny Caputo
- Dipartimento di Scienze e Tecnologie Chimiche, Universita' di Roma Tor Vergata, Roma, Italy
| | | | | |
Collapse
|
24
|
Raafat BM, Saleh A, Shafaa MW, Khedr M, Ghafaar AA. Ginkgo biloba and Angelica archangelica bring back an impartial hepatic apoptotic to anti-apoptotic protein ratio after exposure to technetium 99mTc. Toxicol Ind Health 2012; 29:14-22. [PMID: 22294442 DOI: 10.1177/0748233711433938] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
PURPOSE The aim of this study was to study the effect of ionizing radiation on apoptosis-related protein concentrations as well as the radio-protective role of Ginkgo biloba and Angelica archangelica. The experiments were performed on 68 adult Wistar rats weighing 175 g (±10 g). Animals were subdivided into control group in which the animals received neither the protector nor the isotopes. The second group represents the animals that received 1 mCi of (99m)Tc only. The third group represents the animals that received A. archangelica for 7 days. The fourth group represents the animals that received G. biloba for 7 days. The fifth group represents the animals that received 1 mCi of (99m)Tc once after receiving A. archangelica for 7 days. The sixth group represents the animals that received mCi of (99m)Tc once after receiving G. biloba for 7 days. Radiation was administered as intravenous injection by 1 mCi of (99m)Tc with the legend methoxyisobutylisonitrile for 24 h. The concentration of p53, Bcl2 and malondialdehyde in liver as well as histopathological examination of liver cells were carried out. Results showed that apoptotic to anti-apoptotic protein ratio significantly (p < 0.05) returned to its normal ratio when radioisotopic injection was administered after the protection period for a week by both A. archangelica and G. biloba in a dose based on the animal body weight. Electron microscope photographing supported this finding. CONCLUSION It was concluded that both antioxidants can be used as radio-protective agents in cases of ionizing radiation exposure.
Collapse
Affiliation(s)
- Bassem M Raafat
- Genetic Engineering and Biotechnology Division, National Research Center, Egypt.
| | | | | | | | | |
Collapse
|
25
|
Quiros-Gonzalez I, Sainz RM, Hevia D, Mayo JC. MnSOD drives neuroendocrine differentiation, androgen independence, and cell survival in prostate cancer cells. Free Radic Biol Med 2011; 50:525-36. [PMID: 21056653 DOI: 10.1016/j.freeradbiomed.2010.10.715] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2010] [Revised: 10/19/2010] [Accepted: 10/28/2010] [Indexed: 12/14/2022]
Abstract
An increase in neuroendocrine (NE) cell number has been associated with progression of prostate tumor, one of the most frequent cancers among Western males. We previously reported that mitochondrial manganese superoxide dismutase (MnSOD) increases during the NE differentiation process. The goal of this study was to find whether MnSOD up-regulation is enough to induce NE differentiation. Several human prostate cancer LNCaP cell clones stably overexpressing MnSOD were characterized and two were selected (MnSOD-S4 and MnSOD-S12). MnSOD overexpression induces NE morphological features as well as coexpression of the NE marker synaptophysin. Both MnSOD clones exhibit lower superoxide levels and higher H(2)O(2) levels. MnSOD-overexpressing cells show higher proliferation rates in complete medium, but in steroid-free medium MnSOD-S12 cells are still capable of proliferation. MnSOD up-regulation decreases androgen receptor and prevents its nuclear translocation. MnSOD also induces up-regulation of Bcl-2 and prevents docetaxel-, etoposide-, or TNF-induced cell death. Finally, MnSOD-overexpressing cells enhance growth of androgen-independent PC-3 cells but reduce growth of androgen-dependent cells. These results indicate that redox modulation caused by MnSOD overexpression explains most NE-like features, including morphological changes, NE marker expression, androgen independence, inhibition of apoptosis, and enhancement of cell growth. Many of these events can be associated with the androgen dependent-independent transition during prostate cancer progression.
Collapse
Affiliation(s)
- Isabel Quiros-Gonzalez
- Instituto Universitario de Oncología del Principado de Asturias, Departamento de Morfología y Biología Celular, Facultad de Medicina, Universidad de Oviedo, 33006 Oviedo, Asturias, Spain
| | | | | | | |
Collapse
|
26
|
Fu TY, Hou YY, Chu ST, Liu CF, Huang CH, Chen HC, Hsiao M, Lu PJ, Wang JS, Ger LP. Manganese superoxide dismutase and glutathione peroxidase as prognostic markers in patients with buccal mucosal squamous cell carcinomas. Head Neck 2011; 33:1606-15. [DOI: 10.1002/hed.21653] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2010] [Revised: 09/10/2010] [Accepted: 09/22/2010] [Indexed: 01/05/2023] Open
|
27
|
Zhang Y, Zhang HM, Shi Y, Lustgarten M, Li Y, Qi W, Zhang BX, Van Remmen H. Loss of manganese superoxide dismutase leads to abnormal growth and signal transduction in mouse embryonic fibroblasts. Free Radic Biol Med 2010; 49:1255-62. [PMID: 20638473 PMCID: PMC3418666 DOI: 10.1016/j.freeradbiomed.2010.07.006] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2010] [Revised: 06/18/2010] [Accepted: 07/09/2010] [Indexed: 10/19/2022]
Abstract
Manganese superoxide dismutase (MnSOD) in the mitochondria plays an important role in cellular defense against oxidative damage. Homozygous MnSOD knockout (Sod2(-/-)) mice are neonatal lethal, indicating the essential role of MnSOD in early development. To investigate the potential cellular abnormalities underlying the aborted development of Sod2(-/-) mice, we examined the growth of isolated mouse embryonic fibroblasts (MEFs) from Sod2(-/-) mice. We found that the proliferation of Sod2(-/-) MEFs was significantly decreased compared with wild-type MEFs despite the absence of morphological differences. The Sod2(-/-) MEFs produced less cellular ATP, had lower O(2) consumption, generated more superoxide, and expressed less Prdx3 protein. Furthermore, the loss of MnSOD dramatically altered several markers involved in cell proliferation and growth, including decreased growth stimulatory function of mTOR signaling and enhanced growth inhibitory function of GSK-3β signaling. Interestingly, the G-protein-coupled receptor-mediated intracellular Ca(2+) signal transduction was also severely suppressed in Sod2(-/-) MEFs. Finally, the ratio of microtubule-associated protein light chain 3 (LC3)-II/LC3-I, an index of autophagic activity, was increased in Sod2(-/-) MEFs, consistent with a reduction in mTOR signal transduction. These data demonstrate that MnSOD deficiency results in alterations in several key signaling pathways, which may contribute to the lethal phenotype of Sod2(-/-) mice.
Collapse
Affiliation(s)
- Yiqiang Zhang
- Department of Physiology, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229
- South Texas Veterans Health Care System, San Antonio, Texas 78229
| | - Hong-Mei Zhang
- Department of Medicine, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229
| | - Yun Shi
- Department of Physiology, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229
| | - Michael Lustgarten
- Department of Physiology, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229
| | - Yan Li
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229
| | - Wenbo Qi
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229
| | - Bin-Xian Zhang
- Department of Medicine, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229
| | - Holly Van Remmen
- Department of Physiology, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229
- Department of Cellular and Structural Biology, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229
- South Texas Veterans Health Care System, San Antonio, Texas 78229
| |
Collapse
|
28
|
Lin CY, Wang HM, Kang CJ, Lee LY, Huang SF, Fan KH, Chen EYC, Chen IH, Liao CT, Chang JTC. Primary Tumor Site as a Predictor of Treatment Outcome for Definitive Radiotherapy of Advanced-Stage Oral Cavity Cancers. Int J Radiat Oncol Biol Phys 2010; 78:1011-9. [DOI: 10.1016/j.ijrobp.2009.09.074] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2009] [Revised: 08/31/2009] [Accepted: 09/02/2009] [Indexed: 11/25/2022]
|
29
|
Holley AK, Xu Y, St Clair DK, St Clair WH. RelB regulates manganese superoxide dismutase gene and resistance to ionizing radiation of prostate cancer cells. Ann N Y Acad Sci 2010; 1201:129-36. [PMID: 20649549 PMCID: PMC3107504 DOI: 10.1111/j.1749-6632.2010.05613.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Radiation therapy is in the front line for treatment of localized prostate cancer. However, a significant percentage of patients have radiation-resistant disease. The NF-kappaB pathway is an important factor for radiation resistance, and the classical (canonical) pathway is thought to confer protection of prostate cancer cells from ionizing radiation. Recently, the alternative (non-canonical) pathway, which is involved in prostate cancer aggressiveness, has also been shown to be important for radiation resistance in prostate cancer. The alternative NF-kappaB pathway component RelB protects prostate cancer cells from the detrimental effects of ionizing radiation, in part, by stimulating expression of the mitochondria-localized antioxidant enzyme manganese superoxide dismutase (MnSOD). Blocking RelB activation suppresses MnSOD expression and sensitizes prostate cancer cells to radiation. These results suggest that RelB-mediated modulation of the antioxidant capacity of prostate cancer cells is an important mechanism of radiation resistance. Therefore, targeting RelB activation may prove to be a valuable weapon in the oncologist's arsenal to defeat aggressive and radiation-resistant prostate cancer.
Collapse
Affiliation(s)
- Aaron K Holley
- Graduate Center for Toxicology, University of Kentucky, Lexington, Kentucky 40536, USA
| | | | | | | |
Collapse
|
30
|
Holley AK, Dhar SK, St Clair DK. Manganese superoxide dismutase vs. p53: regulation of mitochondrial ROS. Mitochondrion 2010; 10:649-61. [PMID: 20601193 DOI: 10.1016/j.mito.2010.06.003] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2009] [Revised: 06/18/2010] [Accepted: 06/22/2010] [Indexed: 01/10/2023]
Abstract
Coordination of mitochondrial and nuclear activities is vital for cellular homeostasis, and many signaling molecules and transcription factors are regulated by mitochondria-derived reactive oxygen species (ROS) to carry out this interorganellar communication. The tumor suppressor p53 regulates myriad cellular functions through transcription-dependent and -independent mechanisms at both the nucleus and mitochondria. p53 affect mitochondrial ROS production, in part, by regulating the expression of the mitochondrial antioxidant enzyme manganese superoxide dismutase (MnSOD). Recent evidence suggests mitochondrial regulation of p53 activity through mechanisms that affect ROS production, and a breakdown of communication amongst mitochondria, p53, and the nucleus can have broad implications in disease development.
Collapse
Affiliation(s)
- Aaron K Holley
- Graduate Center for Toxicology, University of Kentucky, Lexington, KY 40536, United States
| | | | | |
Collapse
|
31
|
Feng XP, Yi H, Li MY, Li XH, Yi B, Zhang PF, Li C, Peng F, Tang CE, Li JL, Chen ZC, Xiao ZQ. Identification of biomarkers for predicting nasopharyngeal carcinoma response to radiotherapy by proteomics. Cancer Res 2010; 70:3450-62. [PMID: 20406978 DOI: 10.1158/0008-5472.can-09-4099] [Citation(s) in RCA: 138] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Radiotherapy is the primary treatment for nasopharyngeal cancer (NPC), but radioresistance remains a serious obstacle to successful treatment in many cases. To identify the proteins involved in this resistance and to evaluate their potential for predicting NPC response to radiotherapy, we first established a radioresistant subclone cell line (CNE2-IR) derived from NPC cell line CNE2 by treating the cells with five rounds of sublethal ionizing radiation. Proteomics was then performed to compare the protein profiles of CNE2-IR and CNE2, and a total of 34 differential proteins were identified. Among them, 14-3-3sigma and Maspin were downregulated and GRP78 and Mn-SOD were upregulated in the radioresistant CNE2-IR compared with control CNE2, which was conformed by Western blot. Immunohistochemistry was performed to detect the expression of the four validated proteins in the 39 radioresistant and 51 radiosensitive NPC tissues and their value for predicting NPC response to radiotherapy were evaluated by receiver operating characteristic analysis. The results showed that the downregulation of 14-3-3sigma and Maspin and the upregulation of GRP78 and Mn-SOD were significantly correlated with NPC radioresistance and the combination of the four proteins achieved a sensitivity of 90% and a specificity of 88% in discriminating radiosensitive from radiaoresistant NPC. Furthermore, the resistance to ionizing radiation can be partially reversed by the overexpression of 14-3-3sigma in the CNE2-IR. The data suggest that 14-3-3sigma, Maspin, GRP78, and Mn-SOD are potential biomarkers for predicting NPC response to radiotherapy and their dysregulation may be involved in the radioresistance of NPC.
Collapse
Affiliation(s)
- Xue-Ping Feng
- Key Laboratory of Cancer Proteomics of Chinese Ministry of Health, Xiangya Hospital, Central South University, Hunan Province, China
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
32
|
Sarsour EH, Kumar MG, Chaudhuri L, Kalen AL, Goswami PC. Redox control of the cell cycle in health and disease. Antioxid Redox Signal 2009; 11:2985-3011. [PMID: 19505186 PMCID: PMC2783918 DOI: 10.1089/ars.2009.2513] [Citation(s) in RCA: 284] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
The cellular oxidation and reduction (redox) environment is influenced by the production and removal of reactive oxygen species (ROS). In recent years, several reports support the hypothesis that cellular ROS levels could function as ''second messengers'' regulating numerous cellular processes, including proliferation. Periodic oscillations in the cellular redox environment, a redox cycle, regulate cell-cycle progression from quiescence (G(0)) to proliferation (G(1), S, G(2), and M) and back to quiescence. A loss in the redox control of the cell cycle could lead to aberrant proliferation, a hallmark of various human pathologies. This review discusses the literature that supports the concept of a redox cycle controlling the mammalian cell cycle, with an emphasis on how this control relates to proliferative disorders including cancer, wound healing, fibrosis, cardiovascular diseases, diabetes, and neurodegenerative diseases. We hypothesize that reestablishing the redox control of the cell cycle by manipulating the cellular redox environment could improve many aspects of the proliferative disorders.
Collapse
Affiliation(s)
- Ehab H Sarsour
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa , Iowa City, Iowa, USA
| | | | | | | | | |
Collapse
|
33
|
Du C, Gao Z, Venkatesha VA, Kalen AL, Chaudhuri L, Spitz DR, Cullen JJ, Oberley LW, Goswami PC. Mitochondrial ROS and radiation induced transformation in mouse embryonic fibroblasts. Cancer Biol Ther 2009; 8:1962-71. [PMID: 19738419 DOI: 10.4161/cbt.8.20.9648] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Manganese superoxide dismutase (SOD2) is a nuclear encoded and mitochondria localized antioxidant enzyme that converts mitochondria derived superoxide to hydrogen peroxide. This study investigates the hypothesis that mitochondria derived reactive oxygen species (ROS) regulate ionizing radiation (IR) induced transformation in normal cells. Mouse embryonic fibroblasts (MEFs) with wild type SOD2 (+/+), heterozygous SOD2 (+/-), and homozygous SOD2 (-/-) genotypes were irradiated with equitoxic doses of IR, and assayed for transformation frequency, cellular redox environment, DNA damage, and cell cycle checkpoint activation. Transformation frequency increased ( approximately 5-fold) in SOD2 (-/-) compared to SOD2 (+/+) MEFs. Cellular redox environment (GSH, GSSG, DHE and DCFH-oxidation) did not show any significant change within 24 h post-IR. However, a significant increase in cellular ROS levels was observed at 72 h post-IR in SOD2 (-/-) compared to SOD2 (+/+) MEFs, which was consistent with an increase in GSSG in SOD2 (-/-) MEFs. Late ROS accumulation was associated with an increase in micronuclei frequency in SOD2 (-/-) MEFs. Exit from G(2) was accelerated in irradiated SOD2 (+/-) and SOD2 (-/-) compared to SOD2 (+/+) MEFs. These results support the hypothesis that SOD2 activity and mitochondria generated ROS regulate IR induced transformation in mouse embryonic fibroblasts.
Collapse
Affiliation(s)
- Changbin Du
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa, Iowa City, IA, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
34
|
Characterization of intracellular superoxide dismutase alterations in premalignant and malignant lesions of the oral cavity: correlation with lymph node metastasis. J Cancer Res Clin Oncol 2009; 135:1625-33. [PMID: 19521720 DOI: 10.1007/s00432-009-0610-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2009] [Accepted: 05/25/2009] [Indexed: 01/29/2023]
Abstract
PURPOSE The purpose of this study was to characterize changes in the expression of copper-zinc superoxide dismutase (Cu/Zn-SOD) and manganese SOD (Mn-SOD) in oral squamous-cell carcinoma (OSCC). METHODS Real-time quantitative reverse transcriptase-polymerase chain reaction analysis of Cu/Zn-SOD and Mn-SOD mRNA expression was carried out in 50 pairs of OSCC tissue specimens and corresponding normal tissues. Mn-SOD protein expression was evaluated further in 65 OSCC tissue samples and 33 oral premalignant lesions (OPLs) using immunohistochemistry. RESULTS Significant (P < 0.001) upregulation of Mn-SOD mRNA expression was observed in OSCC tissues compared with the normal tissue counterparts, whereas no significant difference was detected in Cu/Zn-SOD expression. Significant increases in Mn-SOD protein expression were seen in both OPLs (P < 0.001) and OSCC tissue (P < 0.001) together with a high incidence of lymph node metastasis (P = 0.04). CONCLUSIONS Our findings suggested that Mn-SOD overexpression is a frequent and early event during oral carcinogenesis and could contribute to aggressive OSCC.
Collapse
|
35
|
Gao Z, Sarsour EH, Kalen AL, Li L, Kumar MG, Goswami PC. Late ROS accumulation and radiosensitivity in SOD1-overexpressing human glioma cells. Free Radic Biol Med 2008; 45:1501-9. [PMID: 18790046 PMCID: PMC2637374 DOI: 10.1016/j.freeradbiomed.2008.08.009] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2008] [Revised: 07/22/2008] [Accepted: 08/02/2008] [Indexed: 10/21/2022]
Abstract
This study investigates the hypothesis that CuZn superoxide dismutase (SOD1) overexpression confers radioresistance to human glioma cells by regulating the late accumulation of reactive oxygen species (ROS) and the G(2)/M-checkpoint pathway. U118-9 human glioma cells (wild type, neo vector control, and stably overexpressing SOD1) were irradiated (0-10 Gy) and assayed for cell survival, cellular ROS levels, cell-cycle-phase distributions, and cyclin B1 expression. SOD1-overexpressing cells were radioresistant compared to wild-type (wt) and neo vector control (neo) cells. Irradiated wt and neo cells showed a significant increase (approximately twofold) in DHE fluorescence beginning at 2 days postirradiation, which remained elevated at 8 days postirradiation. Interestingly, the late accumulation of ROS was suppressed in irradiated SOD1-overexpressing cells. The increase in ROS levels was followed by a decrease in cell growth and viability and an increase in the percentage of cells with sub-G(1) DNA content. SOD1 overexpression enhanced radiation-induced G(2) accumulation within 24 h postirradiation, which was accompanied by a decrease in cyclin B1 mRNA and protein levels. These results support the hypothesis that long after radiation exposure a "metabolic redox response" regulates radiosensitivity of human glioma cells.
Collapse
Affiliation(s)
- Zhen Gao
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa, Iowa City, IA 52242, USA
| | | | | | | | | | | |
Collapse
|
36
|
Venkatesha VA, Venkataraman S, Sarsour EH, Kalen AL, Buettner GR, Robertson LW, Lehmler HJ, Goswami PC. Catalase ameliorates polychlorinated biphenyl-induced cytotoxicity in nonmalignant human breast epithelial cells. Free Radic Biol Med 2008; 45:1094-102. [PMID: 18691649 PMCID: PMC2614346 DOI: 10.1016/j.freeradbiomed.2008.07.007] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2008] [Revised: 06/16/2008] [Accepted: 07/07/2008] [Indexed: 11/29/2022]
Abstract
Polychlorinated biphenyls (PCBs) are environmental chemical contaminants believed to adversely affect cellular processes. We investigated the hypothesis that PCB-induced changes in the levels of cellular reactive oxygen species (ROS) induce DNA damage resulting in cytotoxicity. Exponentially growing cultures of human nonmalignant breast epithelial cells (MCF10A) were incubated with PCBs for 3 days and assayed for cell number, ROS levels, DNA damage, and cytotoxicity. Exposure to 2,2',4,4',5,5'-hexachlorobiphenyl (PCB153) or 2-(4-chlorophenyl)benzo-1,4-quinone (4-Cl-BQ), a metabolite of 4-chlorobiphenyl (PCB3), significantly decreased cell number and MTS reduction and increased the percentage of cells with sub-G1 DNA content. Results from electron paramagnetic resonance (EPR) spectroscopy showed a 4-fold increase in the steady-state levels of ROS, which was suppressed in cells pretreated with catalase. EPR measurements in cells treated with 4-Cl-BQ detected the presence of a semiquinone radical, suggesting that the increased levels of ROS could be due to the redox cycling of 4-Cl-BQ. A dose-dependent increase in micronuclei frequency was observed in PCB-treated cells, consistent with an increase in histone 2AX phosphorylation. Treatment of cells with catalase blunted the PCB-induced increase in micronuclei frequency and H2AX phosphorylation that was consistent with an increase in cell survival. Our results demonstrate a PCB-induced increase in cellular levels of ROS causing DNA damage, resulting in cell killing.
Collapse
Affiliation(s)
- Venkatasubbaiah A. Venkatesha
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, The University of Iowa, Iowa City, Iowa
| | - Sujatha Venkataraman
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, The University of Iowa, Iowa City, Iowa
| | - Ehab H. Sarsour
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, The University of Iowa, Iowa City, Iowa
| | - Amanda L. Kalen
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, The University of Iowa, Iowa City, Iowa
| | - Garry R. Buettner
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, The University of Iowa, Iowa City, Iowa
| | - Larry W. Robertson
- Occupational & Environmental Health, The University of Iowa, Iowa City, Iowa
| | | | - Prabhat C. Goswami
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, The University of Iowa, Iowa City, Iowa
- Address for correspondence to: Prabhat C. Goswami, PhD, B180 Medical Laboratories, The Free Radical & Radiation Biology Program, Department of Radiation Oncology, The University of Iowa, Iowa City, IA 52242-1181, Fax: 319-335-8039, E-mail:
| |
Collapse
|
37
|
Fisher CJ, Goswami PC. Mitochondria-targeted antioxidant enzyme activity regulates radioresistance in human pancreatic cancer cells. Cancer Biol Ther 2008; 7:1271-9. [PMID: 18497575 DOI: 10.4161/cbt.7.8.6300] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
In recent years, cellular redox environment gained significant attention as a critical regulator of cellular responses to oxidative stress. Cellular redox environment is a balance between production of reactive oxygen species and their removal by antioxidant enzymes. We investigated the hypothesis that mitochondrial antioxidant enzyme activity regulates radioresistance in human pancreatic cancer cells. Vector-control and manganese superoxide dismutase (MnSOD) overexpressing human pancreatic cancer cells were irradiated and assayed for cell survival and activation of the G(2)-checkpoint pathway. Increased MnSOD activity significantly increased cell survival following irradiation with 6 Gy of gamma-radiation (p < 0.05). The MnSOD overexpressing irradiated cells also revealed 3-4 folds increase in the percentage of G(2) cells compared to irradiated vector-control. Furthermore, MnSOD overexpressing irradiated cells exhibited increased loss of phosphorylated histone H2AX protein levels. The radiation-induced increase in cyclin B1 protein levels in irradiated vector-control cells was suppressed in irradiated MnSOD overexpressing cells. Mitochondria-targeted catalase overexpression increased the survival of irradiated cells. These results support the hypothesis that mitochondrial antioxidant enzyme activity and mitochondria-generated reactive oxygen species-signaling (superoxide and hydrogen peroxide) could regulate radiation-induced G(2) checkpoint activation and radioresistance in human pancreatic cancer cells.
Collapse
Affiliation(s)
- Carolyn J Fisher
- Free Radical and Radiation Biology Program, Radiation Oncology Department, University of Iowa, Iowa City, Iowa 52242, USA
| | | |
Collapse
|
38
|
Sarsour EH, Venkataraman S, Kalen AL, Oberley LW, Goswami PC. Manganese superoxide dismutase activity regulates transitions between quiescent and proliferative growth. Aging Cell 2008; 7:405-17. [PMID: 18331617 DOI: 10.1111/j.1474-9726.2008.00384.x] [Citation(s) in RCA: 102] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
In recent years, the intracellular reactive oxygen species (ROS) levels have gained increasing attention as a critical regulator of cellular proliferation. We investigated the hypothesis that manganese superoxide dismutase (MnSOD) activity regulates proliferative and quiescent growth by modulating cellular ROS levels. Decreasing MnSOD activity favored proliferation in mouse embryonic fibroblasts (MEF), while increasing MnSOD activity facilitated proliferating cells' transitions into quiescence. MnSOD +/- and -/- MEFs demonstrated increased superoxide steady-state levels; these fibroblasts failed to exit from the proliferative cycle, and showed increasing cyclin D1 and cyclin B1 protein levels. MnSOD +/- MEFs exhibited an increase in the percentage of G(2) cells compared to MnSOD +/+ MEFs. Overexpression of MnSOD in MnSOD +/- MEFs suppressed superoxide levels and G(2) accumulation, decreased cyclin B1 protein levels, and facilitated cells' transit into quiescence. While ROS are known to regulate differentiation and cell death pathways, both of which are irreversible processes, our results show MnSOD activity and, therefore, mitochondria-derived ROS levels regulate cellular proliferation and quiescence, which are reversible processes essential to prevent aberrant proliferation and subsequent exhaustion of normal cell proliferative capacity. These results support the hypothesis that MnSOD activity regulates a mitochondrial 'ROS-switch' favoring a superoxide-signaling regulating proliferation and a hydrogen peroxide-signaling supporting quiescence.
Collapse
Affiliation(s)
- Ehab H Sarsour
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa, Iowa City, IA 52242, USA
| | | | | | | | | |
Collapse
|