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Singhania M, Zaher A, Pulliam CF, Bayanbold K, Searby CC, Schoenfeld JD, Mapuskar KA, Fath MA, Allen BG, Spitz DR, Petronek MS. Quantitative MRI Evaluation of Ferritin Overexpression in Non-Small-Cell Lung Cancer. Int J Mol Sci 2024; 25:2398. [PMID: 38397073 PMCID: PMC10889593 DOI: 10.3390/ijms25042398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2024] [Revised: 02/13/2024] [Accepted: 02/15/2024] [Indexed: 02/25/2024] Open
Abstract
Cancer cells frequently present elevated intracellular iron levels, which are thought to facilitate an enhanced proliferative capacity. Targeting iron metabolism within cancer cells presents an avenue to enhance therapeutic responses, necessitating the use of non-invasive models to modulate iron manipulation to predict responses. Moreover, the ubiquitous nature of iron necessitates the development of unique, non-invasive markers of metabolic disruptions to develop more personalized approaches and enhance the clinical utility of these approaches. Ferritin, an iron storage enzyme that is often upregulated as a response to iron accumulation, plays a central role in iron metabolism and has been frequently associated with unfavorable clinical outcomes in cancer. Herein, we demonstrate the successful utility, validation, and functionality of a doxycycline-inducible ferritin heavy chain (FtH) overexpression model in H1299T non-small-cell lung cancer (NSCLC) cells. Treatment with doxycycline increased the protein expression of FtH with a corresponding decrease in labile iron in vitro and in vivo, as determined by calcein-AM staining and EPR, respectively. Moreover, a subsequent increase in TfR expression was observed. Furthermore, T2* MR mapping effectively detected FtH expression in our in vivo model. These results demonstrate that T2* relaxation times can be used to monitor changes in FtH expression in tumors with bidirectional correlations depending on the model system. Overall, this study describes the development of an FtH overexpression NSCLC model and its correlation with T2* mapping for potential use in patients to interrogate iron metabolic alterations and predict clinical outcomes.
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Affiliation(s)
- Mekhla Singhania
- Department of Radiation Oncology, Division of Free Radical and Radiation Biology, University of Iowa, Iowa City, IA 52242, USA
| | - Amira Zaher
- Department of Radiation Oncology, Division of Free Radical and Radiation Biology, University of Iowa, Iowa City, IA 52242, USA
| | - Casey F. Pulliam
- Department of Radiation Oncology, Division of Free Radical and Radiation Biology, University of Iowa, Iowa City, IA 52242, USA
| | - Khaliunaa Bayanbold
- Department of Radiation Oncology, Division of Free Radical and Radiation Biology, University of Iowa, Iowa City, IA 52242, USA
| | - Charles C. Searby
- Department of Pediatrics, University of Iowa, Iowa City, IA 52242, USA
| | - Joshua D. Schoenfeld
- Human Oncology & Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA;
| | - Kranti A. Mapuskar
- Department of Radiation Oncology, Division of Free Radical and Radiation Biology, University of Iowa, Iowa City, IA 52242, USA
| | - Melissa A. Fath
- Department of Radiation Oncology, Division of Free Radical and Radiation Biology, University of Iowa, Iowa City, IA 52242, USA
| | - Bryan G. Allen
- Department of Radiation Oncology, Division of Free Radical and Radiation Biology, University of Iowa, Iowa City, IA 52242, USA
| | - Douglas R. Spitz
- Department of Radiation Oncology, Division of Free Radical and Radiation Biology, University of Iowa, Iowa City, IA 52242, USA
| | - Michael S. Petronek
- Department of Radiation Oncology, Division of Free Radical and Radiation Biology, University of Iowa, Iowa City, IA 52242, USA
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2
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Petronek MS, Monga V, Bodeker KL, Kwofie M, Lee CY, Mapuskar KA, Stolwijk JM, Zaher A, Wagner BA, Smith MC, Vollstedt S, Brown H, Chandler ML, Lorack AC, Wulfekuhle JS, Sarkaria JN, Flynn RT, Greenlee JD, Howard MA, Smith BJ, Jones KA, Buettner GR, Cullen JJ, St-Aubin J, Buatti JM, Magnotta VA, Spitz DR, Allen BG. Magnetic Resonance Imaging of Iron Metabolism with T2* Mapping Predicts an Enhanced Clinical Response to Pharmacologic Ascorbate in Patients with GBM. Clin Cancer Res 2024; 30:283-293. [PMID: 37773633 PMCID: PMC10841843 DOI: 10.1158/1078-0432.ccr-22-3952] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2023] [Revised: 05/22/2023] [Accepted: 09/27/2023] [Indexed: 10/01/2023]
Abstract
PURPOSE Pharmacologic ascorbate (P-AscH-) is hypothesized to be an iron (Fe)-dependent tumor-specific adjuvant to chemoradiation in treating glioblastoma (GBM). This study determined the efficacy of combining P-AscH- with radiation and temozolomide in a phase II clinical trial while simultaneously investigating a mechanism-based, noninvasive biomarker in T2* mapping to predict GBM response to P-AscH- in humans. PATIENTS AND METHODS The single-arm phase II clinical trial (NCT02344355) enrolled 55 subjects, with analysis performed 12 months following the completion of treatment. Overall survival (OS) and progression-free survival (PFS) were estimated with the Kaplan-Meier method and compared across patient subgroups with log-rank tests. Forty-nine of 55 subjects were evaluated using T2*-based MRI to assess its utility as an Fe-dependent biomarker. RESULTS Median OS was estimated to be 19.6 months [90% confidence interval (CI), 15.7-26.5 months], a statistically significant increase compared with historic control patients (14.6 months). Subjects with initial T2* relaxation < 50 ms were associated with a significant increase in PFS compared with T2*-high subjects (11.2 months vs. 5.7 months, P < 0.05) and a trend toward increased OS (26.5 months vs. 17.5 months). These results were validated in preclinical in vitro and in vivo model systems. CONCLUSIONS P-AscH- combined with temozolomide and radiotherapy has the potential to significantly enhance GBM survival. T2*-based MRI assessment of tumor iron content is a prognostic biomarker for GBM clinical outcomes. See related commentary by Nabavizadeh and Bagley, p. 255.
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Affiliation(s)
| | - Varun Monga
- Department of Internal Medicine, Division of Hematology and Oncology, University of Iowa; Iowa City, IA, USA
| | - Kellie L. Bodeker
- Department of Radiation Oncology, University of Iowa; Iowa City, IA, USA
| | - Michael Kwofie
- Department of Radiology, University of Iowa; Iowa City, IA, USA
| | - Chu-Yu Lee
- Department of Radiology, University of Iowa; Iowa City, IA, USA
| | - Kranti A. Mapuskar
- Department of Radiation Oncology, University of Iowa; Iowa City, IA, USA
| | | | - Amira Zaher
- Department of Radiation Oncology, University of Iowa; Iowa City, IA, USA
| | - Brett A. Wagner
- Department of Radiation Oncology, University of Iowa; Iowa City, IA, USA
| | - Mark C. Smith
- Department of Radiation Oncology, University of Iowa; Iowa City, IA, USA
| | - Sandy Vollstedt
- Department of Radiation Oncology, University of Iowa; Iowa City, IA, USA
| | - Heather Brown
- Department of Radiation Oncology, University of Iowa; Iowa City, IA, USA
| | - Meghan L. Chandler
- Department of Radiation Oncology, University of Iowa; Iowa City, IA, USA
| | - Amanda C. Lorack
- Department of Radiation Oncology, University of Iowa; Iowa City, IA, USA
| | | | - Jann N. Sarkaria
- Department of Radiation Oncology, Mayo Clinic; Rochester, MN, USA
| | - Ryan T. Flynn
- Department of Radiation Oncology, University of Iowa; Iowa City, IA, USA
| | | | | | - Brian J. Smith
- Department of Biostatistics, University of Iowa; Iowa City, IA, USA
| | - Karra A. Jones
- Department of Pathology, Division of Neuropathology, Duke University; Durham, NC, USA
| | - Garry R. Buettner
- Department of Radiation Oncology, University of Iowa; Iowa City, IA, USA
| | | | - Joel St-Aubin
- Department of Radiation Oncology, University of Iowa; Iowa City, IA, USA
| | - John M. Buatti
- Department of Radiation Oncology, University of Iowa; Iowa City, IA, USA
| | | | - Douglas R. Spitz
- Department of Radiation Oncology, University of Iowa; Iowa City, IA, USA
| | - Bryan G. Allen
- Department of Radiation Oncology, University of Iowa; Iowa City, IA, USA
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3
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Petronek MS, Teferi N, Caster JM, Stolwijk JM, Zaher A, Buatti JM, Hasan D, Wafa EI, Salem AK, Gillan EG, St-Aubin JJ, Buettner GR, Spitz DR, Magnotta VA, Allen BG. Magnetite nanoparticles as a kinetically favorable source of iron to enhance GBM response to chemoradiosensitization with pharmacological ascorbate. Redox Biol 2023; 62:102651. [PMID: 36924683 PMCID: PMC10025281 DOI: 10.1016/j.redox.2023.102651] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Revised: 02/27/2023] [Accepted: 02/27/2023] [Indexed: 03/09/2023] Open
Abstract
Ferumoxytol (FMX) is an FDA-approved magnetite (Fe3O4) nanoparticle used to treat iron deficiency anemia that can also be used as an MR imaging agent in patients that can't receive gadolinium. Pharmacological ascorbate (P-AscH-; IV delivery; plasma levels ≈ 20 mM) has shown promise as an adjuvant to standard of care chemo-radiotherapy in glioblastoma (GBM). Since ascorbate toxicity mediated by H2O2 is enhanced by Fe redox cycling, the current study determined if ascorbate catalyzed the release of ferrous iron (Fe2+) from FMX for enhancing GBM responses to chemo-radiotherapy. Ascorbate interacted with Fe3O4 in FMX to produce redox-active Fe2+ while simultaneously generating increased H2O2 fluxes, that selectively enhanced GBM cell killing (relative to normal human astrocytes) as opposed to a more catalytically active Fe complex (EDTA-Fe3+) in an H2O2 - dependent manner. In vivo, FMX was able to improve GBM xenograft tumor control when combined with pharmacological ascorbate and chemoradiation in U251 tumors that were unresponsive to pharmacological ascorbate therapy. These data support the hypothesis that FMX combined with P-AscH- represents a novel combined modality therapeutic approach to enhance cancer cell selective chemoradiosentization in the management of glioblastoma.
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Affiliation(s)
- M S Petronek
- Department of Radiation Oncology, University of Iowa, Iowa City, IA, USA.
| | - N Teferi
- Department of Neurosurgery, University of Iowa, Iowa City, IA, USA
| | - J M Caster
- Department of Radiation Oncology, University of Iowa, Iowa City, IA, USA
| | - J M Stolwijk
- Department of Radiation Oncology, University of Iowa, Iowa City, IA, USA
| | - A Zaher
- Department of Radiation Oncology, University of Iowa, Iowa City, IA, USA
| | - J M Buatti
- Department of Radiation Oncology, University of Iowa, Iowa City, IA, USA
| | - D Hasan
- Department of Neurosurgery, Duke University, Durham, NC, USA
| | - E I Wafa
- Department of Pharmaceutical Sciences, University of Iowa, Iowa City, IA, USA
| | - A K Salem
- Department of Pharmaceutical Sciences, University of Iowa, Iowa City, IA, USA
| | - E G Gillan
- Department of Chemistry, University of Iowa, Iowa City, IA, USA
| | - J J St-Aubin
- Department of Radiation Oncology, University of Iowa, Iowa City, IA, USA
| | - G R Buettner
- Department of Radiation Oncology, University of Iowa, Iowa City, IA, USA
| | - D R Spitz
- Department of Radiation Oncology, University of Iowa, Iowa City, IA, USA
| | - V A Magnotta
- Department of Radiology, University of Iowa, Iowa City, IA, USA
| | - B G Allen
- Department of Radiation Oncology, University of Iowa, Iowa City, IA, USA.
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4
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Wan S, Zhang G, Liu R, Abbas MN, Cui H. Pyroptosis, ferroptosis, and autophagy cross-talk in glioblastoma opens up new avenues for glioblastoma treatment. Cell Commun Signal 2023; 21:115. [PMID: 37208730 DOI: 10.1186/s12964-023-01108-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Accepted: 03/22/2023] [Indexed: 05/21/2023] Open
Abstract
Glioma is a common primary tumor of the central nervous system (CNS), with glioblastoma multiforme (GBM) being the most malignant, aggressive, and drug resistant. Most drugs are designed to induce cancer cell death, either directly or indirectly, but malignant tumor cells can always evade death and continue to proliferate, resulting in a poor prognosis for patients. This reflects our limited understanding of the complex regulatory network that cancer cells utilize to avoid death. In addition to classical apoptosis, pyroptosis, ferroptosis, and autophagy are recognized as key cell death modalities that play significant roles in tumor progression. Various inducers or inhibitors have been discovered to target the related molecules in these pathways, and some of them have already been translated into clinical treatment. In this review, we summarized recent advances in the molecular mechanisms of inducing or inhibiting pyroptosis, ferroptosis, or autophagy in GBM, which are important for treatment or drug tolerance. We also discussed their links with apoptosis to better understand the mutual regulatory network among different cell death processes. Video Abstract.
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Affiliation(s)
- Sicheng Wan
- State Key Laboratory of Resource Insects, Medical Research Institute, Chongqing, 400715, China
- Chongqing Engineering and Technology Research Center for Silk Biomaterials and Regenerative Medicine, Chongqing, 400715, China
- Engineering Research Center for Cancer Biomedical and Translational Medicine, Southwest University, Chongqing, 400715, China
- Jinfeng Laboratory, Chongqing, 401329, China
| | - Guanghui Zhang
- State Key Laboratory of Resource Insects, Medical Research Institute, Chongqing, 400715, China
- Chongqing Engineering and Technology Research Center for Silk Biomaterials and Regenerative Medicine, Chongqing, 400715, China
- Engineering Research Center for Cancer Biomedical and Translational Medicine, Southwest University, Chongqing, 400715, China
- Jinfeng Laboratory, Chongqing, 401329, China
| | - Ruochen Liu
- State Key Laboratory of Resource Insects, Medical Research Institute, Chongqing, 400715, China
- Chongqing Engineering and Technology Research Center for Silk Biomaterials and Regenerative Medicine, Chongqing, 400715, China
- Engineering Research Center for Cancer Biomedical and Translational Medicine, Southwest University, Chongqing, 400715, China
- Jinfeng Laboratory, Chongqing, 401329, China
| | - Muhammad Nadeem Abbas
- State Key Laboratory of Resource Insects, Medical Research Institute, Chongqing, 400715, China.
- Chongqing Engineering and Technology Research Center for Silk Biomaterials and Regenerative Medicine, Chongqing, 400715, China.
- Engineering Research Center for Cancer Biomedical and Translational Medicine, Southwest University, Chongqing, 400715, China.
- Jinfeng Laboratory, Chongqing, 401329, China.
| | - Hongjuan Cui
- State Key Laboratory of Resource Insects, Medical Research Institute, Chongqing, 400715, China.
- Chongqing Engineering and Technology Research Center for Silk Biomaterials and Regenerative Medicine, Chongqing, 400715, China.
- Engineering Research Center for Cancer Biomedical and Translational Medicine, Southwest University, Chongqing, 400715, China.
- Jinfeng Laboratory, Chongqing, 401329, China.
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5
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Ren G, Lu M, Zhao Z, Qin F, Li K, Chen W, Lin Y. Cobalt Single-Atom Nanozyme Co-Administration with Ascorbic Acid Enables Redox Imbalance for Tumor Catalytic Ablation. ACS Biomater Sci Eng 2023; 9:1066-1076. [PMID: 36617740 DOI: 10.1021/acsbiomaterials.2c01301] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
The elevated antioxidant defense system in cancer cells can lead to resistance to treatments involving ROS. Breaking the redox balance of the cell system through a "open up the source and regulate the flow" strategy can inhibit the growth of cancer cells and thus design a cancer treatment strategy. Here, cobalt single atom-supported N-doped carbon nanozymes (Co SA-N/C) were synthesized via a simple sacrificial template method, which can mimic the properties of ascorbate oxidase and glutathione oxidase effectively. The synthesized Co SA-N/C can induce the generation of active oxygen by accelerating the oxidation of ascorbic acid (AA) and destroy the endogenous active oxygen scavenging system by consuming the main antioxidant, glutathione (GSH). In-depth in vitro and in vivo investigations indicate that compared with solo therapy, Co SA-N/C together with AA can significantly enhance the anti-tumor efficiency by simultaneously elevating oxidative stress and consuming the overexpressed glutathione (GSH) through the redox reaction catalyzed by Co SA-N/C. This work provides a promising route for developing nanozyme-guided and ascorbate-based antitumor agents.
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Affiliation(s)
- Guoyuan Ren
- Department of Chemistry, Capital Normal University, Beijing 100048, China
| | - Mingju Lu
- Department of Chemistry, Capital Normal University, Beijing 100048, China
| | - Zhiqiang Zhao
- Department of Chemistry, Capital Normal University, Beijing 100048, China
| | - Fengjuan Qin
- Beijing Key Laboratory of Construction Tailorable Advanced Functional Materials and Green Applications, School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Kai Li
- Department of Chemistry, Capital Normal University, Beijing 100048, China
| | - Wenxing Chen
- Beijing Key Laboratory of Construction Tailorable Advanced Functional Materials and Green Applications, School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Yuqing Lin
- Department of Chemistry, Capital Normal University, Beijing 100048, China
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6
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Chronic High-Altitude Hypoxia Alters Iron and Nitric Oxide Homeostasis in Fetal and Maternal Sheep Blood and Aorta. Antioxidants (Basel) 2022; 11:antiox11091821. [PMID: 36139895 PMCID: PMC9495375 DOI: 10.3390/antiox11091821] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Revised: 09/09/2022] [Accepted: 09/12/2022] [Indexed: 11/16/2022] Open
Abstract
The mammalian fetus thrives at oxygen tensions much lower than those of adults. Gestation at high altitude superimposes hypoxic stresses on the fetus resulting in increased erythropoiesis. We hypothesized that chronic hypoxia at high altitude alters the homeostasis of iron and bioactive nitric oxide metabolites (NOx) in gestation. To test for this, electron paramagnetic resonance was used to provide unique measurements of iron, metalloproteins, and free radicals in the blood and aorta of fetal and maternal sheep from either high or low altitudes (3801 or 300 m). Using ozone-based chemiluminescence with selectivity for various NOx species, we determined the NOx levels in these samples immediately after collection. These experiments demonstrated a systemic redistribution of iron in high altitude fetuses as manifested by a decrease in both chelatable and total iron in the aorta and an increase in non-transferrin bound iron and total iron in plasma. Likewise, high altitude altered the redox status diversely in fetal blood and aorta. This study also found significant increases in blood and aortic tissue NOx in fetuses and mothers at high altitude. In addition, gradients in NOx concentrations observed between fetus and mother, umbilical artery and vein, and plasma and RBCs demonstrated complex dynamic homeostasis of NOx among these circulatory compartments, such as placental generation and efflux as well as fetal consumption of iron-nitrosyls in RBCs, probably HbNO. In conclusion, these results may suggest the utilization of iron from non-hematopoietic tissues iron for erythropoiesis in the fetus and increased NO bioavailability in response to chronic hypoxic stress at high altitude during gestation.
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7
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Ali MY, Oliva CR, Flor S, Goswami PC, Griguer CE. Cytochrome c oxidase mediates labile iron level and radioresistance in glioblastoma. Free Radic Biol Med 2022; 185:25-35. [PMID: 35476930 DOI: 10.1016/j.freeradbiomed.2022.04.012] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2022] [Revised: 04/11/2022] [Accepted: 04/20/2022] [Indexed: 02/06/2023]
Abstract
Radiotherapy is an important treatment modality for glioblastoma (GBM), yet the initial effectiveness of radiotherapy is eventually lost due to the development of adaptive radioresistance during fractionated radiation therapy. Defining the molecular mechanism(s) responsible for the adaptive radioresistance in GBM is necessary for the development of effective treatment options. The cellular labile iron pool (LIP) is very important for determining the cellular response to radiation, as it contributes to radiation-induced production of reactive oxygen species (ROS) such as lipid radicals through Fenton reactions. Recently, cytochrome c oxidase (CcO), a mitochondrial heme-containing enzyme also involved in regulating ROS production, was found to be involved in GBM chemoresistance. However, the role of LIP and CcO in GBM radioresistance is not known. Herein, we tested the hypothesis that CcO-mediated alterations in the level of labile iron contribute to adaptive radioresistance. Using an in vitro model of GBM adaptive radioresistance, we found an increase in CcO activity in radioresistant cells that associated with a decrease in the cellular LIP, decrease in lipid peroxidation, and a switch in the CcO subunit 4 (COX4) isoform expressed, from COX4-2 to COX4-1. Furthermore, knockdown of COX4-1 in radioresistant GBM cells decreased CcO activity and restored radiosensitivity, whereas overexpression of COX4-1 in radiosensitive cells increased CcO activity and rendered the cells radioresistant. Overexpression of COX4-1 in radiosensitive cells also significantly reduced the cellular LIP and lipid peroxidation. Pharmacological manipulation of the cellular labile iron level using iron chelators altered CcO activity and the radiation response. Overall, these results demonstrate a mechanistic link between CcO activity and LIP in GBM radioresistance and identify the CcO subunit isoform switch from COX4-2 to COX4-1 as a novel biochemical node for adaptive radioresistance of GBM. Manipulation of CcO and the LIP may restore the sensitivity to radiation in radioresistant GBM cells and thereby provide a strategy to improve therapeutic outcome in patients with GBM.
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Affiliation(s)
- Md Yousuf Ali
- Free Radical & Radiation Biology Program, Department of Radiation Oncology, The University of Iowa, Iowa City, IA, 52242, USA; Interdisciplinary Graduate Program in Human Toxicology, The University of Iowa, Iowa City, IA, 52242, USA
| | - Claudia R Oliva
- Free Radical & Radiation Biology Program, Department of Radiation Oncology, The University of Iowa, Iowa City, IA, 52242, USA
| | - Susanne Flor
- Free Radical & Radiation Biology Program, Department of Radiation Oncology, The University of Iowa, Iowa City, IA, 52242, USA
| | - Prabhat C Goswami
- Free Radical & Radiation Biology Program, Department of Radiation Oncology, The University of Iowa, Iowa City, IA, 52242, USA
| | - Corinne E Griguer
- Free Radical & Radiation Biology Program, Department of Radiation Oncology, The University of Iowa, Iowa City, IA, 52242, USA.
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8
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Renner O, Burkard M, Michels H, Vollbracht C, Sinnberg T, Venturelli S. Parenteral high‑dose ascorbate - A possible approach for the treatment of glioblastoma (Review). Int J Oncol 2021; 58:35. [PMID: 33955499 PMCID: PMC8104923 DOI: 10.3892/ijo.2021.5215] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Accepted: 04/05/2021] [Indexed: 12/14/2022] Open
Abstract
For glioblastoma, the treatment with standard of care therapy comprising resection, radiation, and temozolomide results in overall survival of approximately 14-18 months after initial diagnosis. Even though several new therapy approaches are under investigation, it is difficult to achieve life prolongation and/or improvement of patient's quality of life. The aggressiveness and progression of glioblastoma is initially orchestrated by the biological complexity of its genetic phenotype and ability to respond to cancer therapy via changing its molecular patterns, thereby developing resistance. Recent clinical studies of pharmacological ascorbate have demonstrated its safety and potential efficacy in different cancer entities regarding patient's quality of life and prolongation of survival. In this review article, the actual glioblastoma treatment possibilities are summarized, the evidence for pharmacological ascorbate in glioblastoma treatment is examined and questions are posed to identify current gaps of knowledge regarding accessibility of ascorbate to the tumor area. Experiments with glioblastoma cell lines and tumor xenografts have demonstrated that high-dose ascorbate induces cytotoxicity and oxidative stress largely selectively in malignant cells compared to normal cells suggesting ascorbate as a potential therapeutic agent. Further investigations in larger cohorts and randomized placebo-controlled trials should be performed to confirm these findings as well as to improve delivery strategies to the brain, through the inherent barriers and ultimately to the malignant cells.
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Affiliation(s)
- Olga Renner
- Department of Nutritional Biochemistry, University of Hohenheim, D‑70599 Stuttgart, Germany
| | - Markus Burkard
- Department of Nutritional Biochemistry, University of Hohenheim, D‑70599 Stuttgart, Germany
| | - Holger Michels
- Pascoe Pharmazeutische Praeparate GmbH, D‑35394 Giessen, Germany
| | | | - Tobias Sinnberg
- Department of Dermatology, University Hospital Tuebingen, D‑72076 Tuebingen, Germany
| | - Sascha Venturelli
- Department of Nutritional Biochemistry, University of Hohenheim, D‑70599 Stuttgart, Germany
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9
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New promising developments for potential therapeutic applications of high-dose ascorbate as an anticancer drug. Hematol Oncol Stem Cell Ther 2020; 14:179-191. [PMID: 33278349 DOI: 10.1016/j.hemonc.2020.11.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Accepted: 11/11/2020] [Indexed: 12/25/2022] Open
Abstract
Vitamin C (ascorbate) is an essential dietary requirement, with fundamental redox, anti-oxidant functions at physiologic concentrations. Vitamin C is a cofactor for Fe2+ and 2-oxoglutarate-dependent dioxygenases, englobing large families of enzymes, including also epigenetic regulators of DNA and histone methylation. Importantly, vitamin C is involved in the control of the activity of TET (ten-eleven translocation) enzymes, key epigenetic regulators. For this spectrum of activities, often involving pathways deregulated in cancer cells, vitamin C possesses some pharmacologic activities that can be exploited in anticancer therapy. In particular, the capacity of pharmacological doses of vitamin C to target redox imbalance and to rescue deregulated epigenetic program observed in some cancer cells represents a consistent therapeutic potentiality. Several recent studies have identified some cancer subsets that could benefit from the pharmacological activities of vitamin C. The identification of these potentially responsive patients will help to carefully define controlled clinical trials aiming to evaluate the anticancer activity of Vitamin C.
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10
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Cushing CM, Petronek MS, Bodeker KL, Vollstedt S, Brown HA, Opat E, Hollenbeck NJ, Shanks T, Berg DJ, Smith BJ, Smith MC, Monga V, Furqan M, Howard MA, Greenlee JD, Mapuskar KA, St-Aubin J, Flynn RT, Cullen JJ, Buettner GR, Spitz DR, Buatti JM, Allen BG, Magnotta VA. Magnetic resonance imaging (MRI) of pharmacological ascorbate-induced iron redox state as a biomarker in subjects undergoing radio-chemotherapy. Redox Biol 2020; 38:101804. [PMID: 33260088 PMCID: PMC7708874 DOI: 10.1016/j.redox.2020.101804] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 10/29/2020] [Accepted: 11/13/2020] [Indexed: 12/14/2022] Open
Abstract
Pharmacological ascorbate (P-AscH-) combined with standard of care (SOC) radiation and temozolomide is being evaluated in a phase 2 clinical trial (NCT02344355) in the treatment of glioblastoma (GBM). Previously published data demonstrated that paramagnetic iron (Fe3+) catalyzes ascorbate's oxidation to form diamagnetic iron (Fe2+). Because paramagnetic Fe3+ may influence relaxation times observed in MR imaging, quantitative MR imaging of P-AscH--induced changes in redox-active Fe was assessed as a biomarker for therapy response. Gel phantoms containing either Fe3+ or Fe2+ were imaged with T2* and quantitative susceptibility mapping (QSM). Fifteen subjects receiving P-AscH- plus SOC underwent T2* and QSM imaging four weeks into treatment. Subjects were scanned: pre-P-AscH- infusion, post-P-AscH- infusion, and post-radiation (3-4 h between scans). Changes in T2* and QSM relaxation times in tumor and normal tissue were calculated and compared to changes in Fe3+ and Fe2+ gel phantoms. A GBM mouse model was used to study the relationship between the imaging findings and the labile iron pool. Phantoms containing Fe3+ demonstrated detectable changes in T2* and QSM relaxation times relative to Fe2+ phantoms. Compared to pre-P-AscH-, GBM T2* and QSM imaging were significantly changed post-P-AscH- infusion consistent with conversion of Fe3+ to Fe2+. No significant changes in T2* or QSM were observed in normal brain tissue. There was moderate concordance between T2* and QSM changes in both progression free survival and overall survival. The GBM mouse model showed similar results with P-AscH- inducing greater changes in tumor labile iron pools compared to the normal tissue. CONCLUSIONS: T2* and QSM MR-imaging responses are consistent with P-AscH- reducing Fe3+ to Fe2+, selectively in GBM tumor volumes and represent a potential biomarker of response. This study is the first application using MR imaging in humans to measure P-AscH--induced changes in redox-active iron.
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Affiliation(s)
- Cameron M Cushing
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, University of Iowa Hospitals and Clinics, USA
| | - Michael S Petronek
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, University of Iowa Hospitals and Clinics, USA
| | - Kellie L Bodeker
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, University of Iowa Hospitals and Clinics, USA
| | - Sandy Vollstedt
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, University of Iowa Hospitals and Clinics, USA
| | - Heather A Brown
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, University of Iowa Hospitals and Clinics, USA
| | - Emyleigh Opat
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, University of Iowa Hospitals and Clinics, USA
| | - Nancy J Hollenbeck
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, University of Iowa Hospitals and Clinics, USA
| | - Thomas Shanks
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, University of Iowa Hospitals and Clinics, USA
| | - Daniel J Berg
- Division of Hematology and Oncology, Department of Internal Medicine, Holden Comprehensive Cancer Center, University of Iowa Hospitals & Clinics, Iowa City, IA, USA
| | - Brian J Smith
- Department of Biostatistics, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA, USA
| | - Mark C Smith
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, University of Iowa Hospitals and Clinics, USA
| | - Varun Monga
- Division of Hematology and Oncology, Department of Internal Medicine, Holden Comprehensive Cancer Center, University of Iowa Hospitals & Clinics, Iowa City, IA, USA
| | - Muhammad Furqan
- Division of Hematology and Oncology, Department of Internal Medicine, Holden Comprehensive Cancer Center, University of Iowa Hospitals & Clinics, Iowa City, IA, USA
| | - Matthew A Howard
- Department of Neurosurgery, University of Iowa Hospitals & Clinics, Iowa City, IA, USA
| | - Jeremy D Greenlee
- Department of Neurosurgery, University of Iowa Hospitals & Clinics, Iowa City, IA, USA
| | - Kranti A Mapuskar
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, University of Iowa Hospitals and Clinics, USA
| | - Joel St-Aubin
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, University of Iowa Hospitals and Clinics, USA
| | - Ryan T Flynn
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, University of Iowa Hospitals and Clinics, USA
| | - Joseph J Cullen
- Department of Surgery, University of Iowa College of Medicine, Iowa City, IA, USA; Department of Radiation Oncology, University of Iowa College of Medicine, Iowa City, IA, USA; Holden Comprehensive Cancer Center, Iowa City, IA, USA; Veterans Affairs Medical Center, Iowa City, IA, USA
| | - Garry R Buettner
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, University of Iowa Hospitals and Clinics, USA
| | - Douglas R Spitz
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, University of Iowa Hospitals and Clinics, USA
| | - John M Buatti
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, University of Iowa Hospitals and Clinics, USA
| | - Bryan G Allen
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, University of Iowa Hospitals and Clinics, USA.
| | - Vincent A Magnotta
- Department of Radiology, Holden Comprehensive Cancer Center, University of Iowa Hospitals and Clinics, USA.
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11
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Erudaitius DT, Buettner GR, Rodgers VGJ. The latency of peroxisomal catalase in terms of effectiveness factor for pancreatic and glioblastoma cancer cell lines in the presence of high concentrations of H 2O 2: Implications for the use of pharmacological ascorbate in cancer therapy. Free Radic Biol Med 2020; 156:20-25. [PMID: 32522584 PMCID: PMC7434663 DOI: 10.1016/j.freeradbiomed.2020.05.023] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Accepted: 05/26/2020] [Indexed: 02/07/2023]
Abstract
Previous research has identified variation in cancer cell line response to high levels of extracellular H2O2 (eH2O2) exposure. This directly contributes to our understanding cellular efficacy of pharmacological ascorbate (P-AscH-) therapy. Here we investigate the factors contributing to latency of peroxisomal catalase of a cell and the importance of latency in evaluating cell exposure to eH2O2. First, we develop a mathematical framework for the latency of catalase in terms of an effectiveness factor, ηeff, to describe the catalase activity in the presence of high levels of eH2O2. A simplified relationship emerges, [Formula: see text] when mprp/Dij≪1, where mp,rp, and [Formula: see text] are the experimentally determined peroxisome permeability, average peroxisome radius, and the pseudo first-order reaction rate constant, respectively. [Formula: see text] is the catalase concentration in the peroxisome and k2=1.7x107M-1s-1. Next, previously published parameters are used to determine the latency effect of the cell lines: normal pancreatic cells (H6c7), pancreatic cancer cells (MIA PaCa-2), and glioblastoma cells (LN-229, T98G, and U-87), all which vary in their susceptibility to exposure to high eH2O2. The results show that effectiveness is not significantly different except for the most susceptible, MIA PaCa-2 cell line, which is higher when compared to all other cell lines. This result is counterintuitive and further implies that latency, as a single parameter, is ineffective in forecasting cell line susceptibility to P-AscH- therapy equivalent eH2O. Thus, further research remains necessary to identify why cancer cells vary in susceptibility to P-AscH- therapy.
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Affiliation(s)
- Dieanira T Erudaitius
- Department of Bioengineering, University of California, Riverside, Riverside, CA, 92521, USA
| | - Garry R Buettner
- Free Radical & Radiation Biology, Department of Radiation Oncology, University of Iowa College of Medicine, Iowa City, IA, 52242, USA
| | - Victor G J Rodgers
- Department of Bioengineering, University of California, Riverside, Riverside, CA, 92521, USA.
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12
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The Action of JAK/STAT3 and BMP/HJV/SMAD Signaling Pathways on Hepcidin Suppression by Tucum-do-Cerrado in a Normal and Iron-Enriched Diets. Nutrients 2020; 12:nu12051515. [PMID: 32456060 PMCID: PMC7285201 DOI: 10.3390/nu12051515] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2020] [Revised: 05/13/2020] [Accepted: 05/15/2020] [Indexed: 11/25/2022] Open
Abstract
The Brazilian savanna fruit, tucum-do-cerrado (Bactris setosa Mart.) reduces hepatic hepcidin levels. Therefore, we investigated the effect of tucum-do-cerrado on the TfR/HFE and/or BMP/HJV/SMAD and JAK/STAT pathways, in normal and excess iron conditions. Rats were treated with: control diet (CT); control diet +15% tucum-do-cerrado (Tuc); iron-enriched diet (+Fe); or iron-enriched diet +15% tucum-do-cerrado (Tuc+Fe). Tucum-do-cerrado (Tuc) decreased hepatic Hamp and Hjv mRNA levels but did not alter Bmp6, Smad7, Tfr1, and Hfe mRNA levels; pSMAD1/5/8 and pSTAT3 protein levels; labile iron pool (LIP); and inflammatory biomarkers, compared to the CT group. The iron-enriched diet increased Hamp mRNA levels, as well as pSMAD1/5/8 and pSTAT3 protein levels, while no difference was observed in Hjv, Bmp6, Smad7, Tfr1, and Hfe mRNA levels and LIP compared to the CT group. The association of tucum-do-cerrado with the iron-enriched diet (Tuc+Fe) decreased Hamp, Hjv, Bmp6, and Hfe mRNA levels and pSTAT3 protein content compared to the +Fe group, while increased Hamp and decreased Hfe mRNA levels compared to the Tuc group. Therefore, the inhibition of hepatic hepcidin by tucum-do-cerrado consumption may involve the downregulation of intestinal Dmt1 and hepatic Hjv expression and deacetylation mediated by SIRT1 by a mechanism that is independent of tissue iron content. However, in excess iron conditions, the modulation of hepatic hepcidin expression by tucum-do-cerrado seems to be partially mediated by the inflammatory signaling pathway, as well as involves the chelating activity of tucum-do-cerrado.
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13
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Synergistic effect of fasting-mimicking diet and vitamin C against KRAS mutated cancers. Nat Commun 2020; 11:2332. [PMID: 32393788 PMCID: PMC7214421 DOI: 10.1038/s41467-020-16243-3] [Citation(s) in RCA: 83] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Accepted: 04/16/2020] [Indexed: 01/05/2023] Open
Abstract
Fasting-mimicking diets delay tumor progression and sensitize a wide range of tumors to chemotherapy, but their therapeutic potential in combination with non-cytotoxic compounds is poorly understood. Here we show that vitamin C anticancer activity is limited by the up-regulation of the stress-inducible protein heme-oxygenase-1. The fasting-mimicking diet selectivity reverses vitamin C-induced up-regulation of heme-oxygenase-1 and ferritin in KRAS-mutant cancer cells, consequently increasing reactive iron, oxygen species, and cell death; an effect further potentiated by chemotherapy. In support of a potential role of ferritin in colorectal cancer progression, an analysis of The Cancer Genome Atlas Database indicates that KRAS mutated colorectal cancer patients with low intratumor ferritin mRNA levels display longer 3- and 5-year overall survival. Collectively, our data indicate that the combination of a fasting-mimicking diet and vitamin C represents a promising low toxicity intervention to be tested in randomized clinical trials against colorectal cancer and possibly other KRAS mutated tumors. Fasting diets are emerging as an approach to delay tumor progression and improve cancer therapies. Here, the authors show that the combination of fasting-mimicking diet with vitamin C decreases tumor development and increases chemotherapy efficacy in KRAS-mutant cancer.
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14
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Chen PH, Wu J, Ding CKC, Lin CC, Pan S, Bossa N, Xu Y, Yang WH, Mathey-Prevot B, Chi JT. Kinome screen of ferroptosis reveals a novel role of ATM in regulating iron metabolism. Cell Death Differ 2020; 27:1008-1022. [PMID: 31320750 PMCID: PMC7206124 DOI: 10.1038/s41418-019-0393-7] [Citation(s) in RCA: 154] [Impact Index Per Article: 38.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Revised: 06/22/2019] [Accepted: 07/01/2019] [Indexed: 01/18/2023] Open
Abstract
Ferroptosis is a specialized iron-dependent cell death that is associated with lethal lipid peroxidation. Modulation of ferroptosis may have therapeutic potential since it has been implicated in various human diseases as well as potential antitumor activities. However, much remains unknown about the underlying mechanisms and genetic determinants of ferroptosis. Given the critical role of kinases in most biological processes and the availability of various kinase inhibitors, we sought to systemically identify kinases essential for ferroptosis. We performed a forward genetic-based kinome screen against ferroptosis in MDA-MB-231 cells triggered by cystine deprivation. This screen identified 34 essential kinases involved in TNFα and NF-kB signaling. Unexpectedly, the DNA damage response serine/threonine kinase ATM (mutated in Ataxia-Telangiectasia) was found to be essential for ferroptosis. The pharmacological or genetic inhibition of ATM consistently rescued multiple cancer cells from ferroptosis triggered by cystine deprivation or erastin. Instead of the canonical DNA damage pathways, ATM inhibition rescued ferroptosis by increasing the expression of iron regulators involved in iron storage (ferritin heavy and light chain, FTH1 and FTL) and export (ferroportin, FPN1). The coordinated changes of these iron regulators during ATM inhibition resulted in a lowering of labile iron and prevented the iron-dependent ferroptosis. Furthermore, we found that ATM inhibition enhanced the nuclear translocation of metal-regulatory transcription factor 1 (MTF1), responsible for regulating expression of Ferritin/FPN1 and ferroptosis protection. Genetic depletion of MTF-1 abolished the regulation of iron-regulatory elements by ATM and resensitized the cells to ferroptosis. Together, we have identified an unexpected ATM-MTF1-Ferritin/FPN1 regulatory axis as novel determinants of ferroptosis through regulating labile iron levels.
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Affiliation(s)
- Po-Han Chen
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC, USA.,Duke Center for Genomic and Computational Biology, Duke University, Durham, NC, USA
| | - Jianli Wu
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC, USA.,Duke Center for Genomic and Computational Biology, Duke University, Durham, NC, USA
| | - Chien-Kuang Cornelia Ding
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC, USA.,Duke Center for Genomic and Computational Biology, Duke University, Durham, NC, USA
| | - Chao-Chieh Lin
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC, USA.,Duke Center for Genomic and Computational Biology, Duke University, Durham, NC, USA
| | - Samuel Pan
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC, USA.,Duke Center for Genomic and Computational Biology, Duke University, Durham, NC, USA
| | - Nathan Bossa
- Department of Civil and Environmental Engineering, Duke University, Durham, NC, USA
| | - Yitong Xu
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC, USA.,Duke Center for Genomic and Computational Biology, Duke University, Durham, NC, USA
| | - Wen-Hsuan Yang
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC, USA.,Duke Center for Genomic and Computational Biology, Duke University, Durham, NC, USA
| | - Bernard Mathey-Prevot
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC, USA
| | - Jen-Tsan Chi
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC, USA. .,Duke Center for Genomic and Computational Biology, Duke University, Durham, NC, USA.
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15
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Badu-Boateng C, Naftalin RJ. Ascorbate and ferritin interactions: Consequences for iron release in vitro and in vivo and implications for inflammation. Free Radic Biol Med 2019; 133:75-87. [PMID: 30268889 DOI: 10.1016/j.freeradbiomed.2018.09.041] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Revised: 09/25/2018] [Accepted: 09/26/2018] [Indexed: 01/19/2023]
Abstract
This review discusses the chemical mechanisms of ascorbate-dependent reduction and solubilization of ferritin's ferric iron core and subsequent release of ferrous iron. The process is accelerated by low concentrations of Fe(II) that increase ferritin's intrinsic ascorbate oxidase activity, hence increasing the rate of ascorbate radical formation. These increased rates of ascorbate oxidation provide reducing equivalents (electrons) to ferritin's core and speed the core reduction rates with subsequent solubilization and release of Fe(II). Ascorbate-dependent solubilization of ferritin's iron core has consequences relating to the interpretation of 59Fe uptake sourced from 59Fe-lebelled holotransferrin into ferritin. Ascorbate-dependent reduction of the ferritin core iron solubility increases the size of ferritin's iron exchangeable pool and hence the rate and amount of exchange uptake of 59Fe into ferritin, whilst simultaneously increasing net iron release rate from ferritin. This may rationalize the inconsistency that ascorbate apparently stabilizes 59Fe ferritin and retards lysosomal ferritinolysis and whole cell 59Fe release, whilst paradoxically increasing the rate of net iron release from ferritin. This capacity of ascorbate and iron to synergise ferritin iron release has pathological significance, as it lowers the concentration at which ascorbate activates ferritin's iron release to within the physiological range (50-250 μM). These effects have relevance to inflammatory pathology and to the pro-oxidant effects of ascorbate in cancer therapy and cell death by ferroptosis.
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Affiliation(s)
- Charles Badu-Boateng
- Kings, BHF Centre of Research Excellence, School of Cardiovascular Medicine & Sciences, Faculty of Life Sciences & Medicine, King's College London, 150 Stamford Street, London SE1 9NH, UK
| | - Richard J Naftalin
- Kings, BHF Centre of Research Excellence, School of Cardiovascular Medicine & Sciences, Faculty of Life Sciences & Medicine, King's College London, 150 Stamford Street, London SE1 9NH, UK
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16
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Schoenfeld JD, Alexander MS, Waldron TJ, Sibenaller ZA, Spitz DR, Buettner GR, Allen BG, Cullen JJ. Pharmacological Ascorbate as a Means of Sensitizing Cancer Cells to Radio-Chemotherapy While Protecting Normal Tissue. Semin Radiat Oncol 2019; 29:25-32. [PMID: 30573181 PMCID: PMC6310038 DOI: 10.1016/j.semradonc.2018.10.006] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Chemoradiation has remained the standard of care treatment for many of the most aggressive cancers. However, despite effective toxicity to cancer cells, current chemoradiation regimens are limited in efficacy due to significant normal cell toxicity. Thus, efforts have been made to identify agents demonstrating selective toxicity, whereby treatments simultaneously sensitize cancer cells to protect normal cells from chemoradiation. Pharmacological ascorbate (intravenous infusions of vitamin C resulting in plasma ascorbate concentrations ≥20 mM; P-AscH-) has demonstrated selective toxicity in a variety of preclinical tumor models and is currently being assessed as an adjuvant to standard-of-care therapies in several early phase clinical trials. This review summarizes the most current preclinical and clinical data available demonstrating the multidimensional role of P-AscH- in cancer therapy including: selective toxicity to cancer cells via a hydrogen peroxide (H2O2)-mediated mechanism; action as a sensitizing agent of cancer cells to chemoradiation; a protectant of normal tissues exposed to chemoradiation; and its safety and tolerability in clinical trials.
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Affiliation(s)
- Joshua D Schoenfeld
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Iowa City, IA
| | - Matthew S Alexander
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Iowa City, IA; Department of Surgery, Iowa City, IA
| | - Timothy J Waldron
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Iowa City, IA; University of Iowa Carver College of Medicine, Iowa City, IA; The Holden Comprehensive Cancer Center, Iowa City, IA
| | - Zita A Sibenaller
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Iowa City, IA
| | - Douglas R Spitz
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Iowa City, IA; University of Iowa Carver College of Medicine, Iowa City, IA; The Holden Comprehensive Cancer Center, Iowa City, IA
| | - Garry R Buettner
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Iowa City, IA; University of Iowa Carver College of Medicine, Iowa City, IA; The Holden Comprehensive Cancer Center, Iowa City, IA
| | - Bryan G Allen
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Iowa City, IA; University of Iowa Carver College of Medicine, Iowa City, IA; The Holden Comprehensive Cancer Center, Iowa City, IA
| | - Joseph J Cullen
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Iowa City, IA; Department of Surgery, Iowa City, IA; University of Iowa Carver College of Medicine, Iowa City, IA; The Holden Comprehensive Cancer Center, Iowa City, IA; Veterans Affairs Medical Center, Iowa City, IA.
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17
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Chaiswing L, St. Clair WH, St. Clair DK. Redox Paradox: A Novel Approach to Therapeutics-Resistant Cancer. Antioxid Redox Signal 2018; 29:1237-1272. [PMID: 29325444 PMCID: PMC6157438 DOI: 10.1089/ars.2017.7485] [Citation(s) in RCA: 79] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/25/2017] [Accepted: 01/05/2018] [Indexed: 02/06/2023]
Abstract
SIGNIFICANCE Cancer cells that are resistant to radiation and chemotherapy are a major problem limiting the success of cancer therapy. Aggressive cancer cells depend on elevated intracellular levels of reactive oxygen species (ROS) to proliferate, self-renew, and metastasize. As a result, these aggressive cancers maintain high basal levels of ROS compared with normal cells. The prominence of the redox state in cancer cells led us to consider whether increasing the redox state to the condition of oxidative stress could be used as a successful adjuvant therapy for aggressive cancers. Recent Advances: Past attempts using antioxidant compounds to inhibit ROS levels in cancers as redox-based therapy have met with very limited success. However, recent clinical trials using pro-oxidant compounds reveal noteworthy results, which could have a significant impact on the development of strategies for redox-based therapies. CRITICAL ISSUES The major objective of this review is to discuss the role of the redox state in aggressive cancers and how to utilize the shift in redox state to improve cancer therapy. We also discuss the paradox of redox state parameters; that is, hydrogen peroxide (H2O2) as the driver molecule for cancer progression as well as a target for cancer treatment. FUTURE DIRECTIONS Based on the biological significance of the redox state, we postulate that this system could potentially be used to create a new avenue for targeted therapy, including the potential to incorporate personalized redox therapy for cancer treatment.
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Affiliation(s)
- Luksana Chaiswing
- Department of Toxicology and Cancer Biology, University of Kentucky-Lexington, Lexington, Kentucky
| | - William H. St. Clair
- Department of Radiation Medicine, University of Kentucky-Lexington, Lexington, Kentucky
| | - Daret K. St. Clair
- Department of Toxicology and Cancer Biology, University of Kentucky-Lexington, Lexington, Kentucky
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18
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Alexander MS, O'Leary BR, Wilkes JG, Gibson AR, Wagner BA, Du J, Sarsour E, Hwang RF, Buettner GR, Cullen JJ. Enhanced Pharmacological Ascorbate Oxidation Radiosensitizes Pancreatic Cancer. Radiat Res 2018; 191:43-51. [PMID: 30376411 DOI: 10.1667/rr15189.1] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Pharmacologic ascorbate (P-AscH-) is emerging as a promising adjuvant for advanced pancreatic cancer. P-AscH- generates hydrogen peroxide (H2O2), leading to selective cancer cell cytotoxicity. Catalytic manganoporphyrins, such as MnT4MPyP, can increase the rate of oxidation of P-AscH-, thereby increasing the flux of H2O2, resulting in increased cytotoxicity. We hypothesized that a multimodal treatment approach, utilizing a combination of P-AscH-, ionizing radiation and MnT4MPyP, would result in significant flux of H2O2 and pancreatic cancer cytotoxicity. P-AscH- with MnT4MPyP increased the rate of oxidation of P-AscH- and produced radiosensitization in all pancreatic cancer cell lines tested. Three-dimensional (3D) cell cultures demonstrated resistance to P-AscH-, radiation or MnT4MPyP treatments alone; however, combined treatment with P-AscH- and MnT4MPyP resulted in the inhibition of tumor growth, particularly when also combined with radiation. In vivo experiments using a murine model demonstrated an increased rate of ascorbate oxidation when combinations of P-AscH- with MnT4MPyP were given, thus acting as a radiosensitizer. The translational potential was demonstrated by measuring increased ascorbate oxidation ex vivo, whereby MnT4MPyP was added exogenously to plasma samples from patients treated with P-AscH- and radiation. Combination treatment utilizing P-AscH-, manganoporphyrin and radiation results in significant cytotoxicity secondary to enhanced ascorbate oxidation and an increased flux of H2O2. This multimodal approach has the potential to be an effective treatment for pancreatic ductal adenocarcinoma.
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Affiliation(s)
| | | | - Justin G Wilkes
- a Department of Surgery, University of Iowa, Iowa City, Iowa
| | - Adrienne R Gibson
- b Free Radical and Radiation Biology Program, University of Iowa, Iowa City, Iowa
| | - Brett A Wagner
- b Free Radical and Radiation Biology Program, University of Iowa, Iowa City, Iowa
| | - Juan Du
- a Department of Surgery, University of Iowa, Iowa City, Iowa
| | - Ehab Sarsour
- b Free Radical and Radiation Biology Program, University of Iowa, Iowa City, Iowa
| | - Rosa F Hwang
- c Breast Surgical Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Garry R Buettner
- b Free Radical and Radiation Biology Program, University of Iowa, Iowa City, Iowa
| | - Joseph J Cullen
- a Department of Surgery, University of Iowa, Iowa City, Iowa.,d The University of Iowa Holden Comprehensive Cancer Center, Iowa City, Iowa.,e Veterans Affairs Medical Center, Iowa City, Iowa
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19
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Zhao CN, Li Y, Meng X, Li S, Liu Q, Tang GY, Gan RY, Li HB. Insight into the roles of vitamins C and D against cancer: Myth or truth? Cancer Lett 2018; 431:161-170. [DOI: 10.1016/j.canlet.2018.05.039] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Revised: 05/17/2018] [Accepted: 05/24/2018] [Indexed: 02/07/2023]
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20
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Erudaitius D, Mantooth J, Huang A, Soliman J, Doskey CM, Buettner GR, Rodgers VGJ. Calculated cell-specific intracellular hydrogen peroxide concentration: Relevance in cancer cell susceptibility during ascorbate therapy. Free Radic Biol Med 2018; 120:356-367. [PMID: 29601946 PMCID: PMC6160292 DOI: 10.1016/j.freeradbiomed.2018.03.044] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Revised: 03/13/2018] [Accepted: 03/25/2018] [Indexed: 01/24/2023]
Abstract
The high extracellular hydrogen peroxide (H2O2) concentrations generated during pharmacological ascorbate (P-AscH-) therapy has been shown to exhibit a high flux into susceptible cancer cells leading to a decrease in clonogenic survival. It is hypothesized that the intracellular H2O2 concentration for susceptibility is independent of cell type and that the variation observed in dosing is associated with differences in the cell-specific overall steady-state intracellular H2O2 concentration values. The steady-state variation in intracellular H2O2 concentration is coupled to a number of cellular specific transport and reaction factors including catalase activity and membrane permeability. Here a lumped-parameter mathematical modeling approach, assuming a catalase-dominant peroxide removal mechanism, is used to calculate intracellular H2O2 concentration for several cell lines. Experimental measurements of critical parameters pertaining to the model are obtained. The cell lines investigated are normal pancreatic cells, H6c7, the pancreatic cancer cell line, MIA PaCa-2 and the glioblastoma cell lines, LN-229, T98G, and U-87; all which vary in susceptibility. The intracellular H2O2 concentration estimates are correlated with the clonogenic surviving fraction for each cell line, in-vitro. The results showed that, despite the fact that the experimental parameters including catalase concentration and plasma membrane permeability demonstrated significant variability across cell lines, the calculated steady-state intracellular to extracellular H2O2 concentration ratio did not vary significantly across cell lines. Thus, the calculated intracellular H2O2 concentration is not unique in characterizing susceptibility. These results imply that, although intracellular H2O2 concentration plays a key role in cellular susceptibility to P-AscH- adjuvant therapy, its overall contribution in a unifying mechanism across cell types is complex.
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Affiliation(s)
- Dieanira Erudaitius
- Department of Bioengineering, University of California, Riverside, Riverside, CA 92521, USA
| | - Jacqueline Mantooth
- Department of Bioengineering, University of California, Riverside, Riverside, CA 92521, USA
| | - Andrew Huang
- Department of Neuroscience, University of California, Riverside, Riverside, CA 92521, USA
| | - Jesse Soliman
- Department of Bioengineering, University of California, Riverside, Riverside, CA 92521, USA
| | - Claire M Doskey
- Center for Integrative Toxicology, Michigan State University, East Lansing, MI 48823, USA
| | - Garry R Buettner
- Free Radical & Radiation Biology, Department of Radiation Oncology, University of Iowa College of Medicine, Iowa City, IA 52242, USA
| | - Victor G J Rodgers
- Department of Bioengineering, University of California, Riverside, Riverside, CA 92521, USA.
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21
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Quantitative comparison of different iron forms in the temporal cortex of Alzheimer patients and control subjects. Sci Rep 2018; 8:6898. [PMID: 29720594 PMCID: PMC5932027 DOI: 10.1038/s41598-018-25021-7] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Accepted: 04/10/2018] [Indexed: 12/25/2022] Open
Abstract
We present a quantitative study of different molecular iron forms found in the temporal cortex of Alzheimer (AD) patients. Applying the methodology we developed in our previous work, we quantify the concentrations of non-heme Fe(III) by Electron Paramagnetic Resonance (EPR), magnetite/maghemite and ferrihydrite by SQUID magnetometry, together with the MRI transverse relaxation rate [Formula: see text], to obtain a systematic view of molecular iron in the temporal cortex. Significantly higher values of [Formula: see text], a larger concentration of ferrihydrite, and a larger magnetic moment of magnetite/maghemite particles are found in the brain of AD patients. Moreover, we found correlations between the concentration of the iron detected by EPR, the concentration of the ferrihydrite mineral and the average iron loading of ferritin. We discuss these findings in the framework of iron dis-homeostasis, which has been proposed to occur in the brain of AD patients.
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22
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Islam MT. Ascorbic acid: still controversial when used against cancer resistance? DRUGS & THERAPY PERSPECTIVES 2017. [DOI: 10.1007/s40267-017-0475-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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23
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Brandt KE, Falls KC, Schoenfeld JD, Rodman SN, Gu Z, Zhan F, Cullen JJ, Wagner BA, Buettner GR, Allen BG, Berg DJ, Spitz DR, Fath MA. Augmentation of intracellular iron using iron sucrose enhances the toxicity of pharmacological ascorbate in colon cancer cells. Redox Biol 2017; 14:82-87. [PMID: 28886484 PMCID: PMC5591450 DOI: 10.1016/j.redox.2017.08.017] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Revised: 08/17/2017] [Accepted: 08/21/2017] [Indexed: 01/20/2023] Open
Abstract
Pharmacological doses (> 1 mM) of ascorbate (a.k.a., vitamin C) have been shown to selectively kill cancer cells through a mechanism that is dependent on the generation of H2O2 at doses that are safely achievable in humans using intravenous administration. The process by which ascorbate oxidizes to form H2O2 is thought to be mediated catalytically by redox active metal ions such as iron (Fe). Because intravenous iron sucrose is often administered to colon cancer patients to help mitigate anemia, the current study assessed the ability of pharmacological ascorbate to kill colon cancer cells in the presence and absence of iron sucrose. In vitro survival assays showed that 10 mM ascorbate exposure (2 h) clonogenically inactivated 40–80% of exponentially growing colon cancer cell lines (HCT116 and HT29). When the H2O2 scavenging enzyme, catalase, was added to the media, or conditionally over-expressed using a doxycycline inducible vector, the toxicity of pharmacological ascorbate was significantly blunted. When colon cancer cells were treated in the presence or absence of 250 µM iron sucrose, then rinsed, and treated with 10 mM ascorbate, the cells demonstrated increased levels of labile iron that resulted in significantly increased clonogenic cell killing, compared to pharmacological ascorbate alone. Interestingly, when colon cancer cells were treated with iron sucrose for 1 h and then 10 mM ascorbate was added to the media in the continued presence of iron sucrose, there was no enhancement of toxicity despite similar increases in intracellular labile iron. The combination of iron chelators, deferoxamine and diethylenetriaminepentaacetic acid, significantly inhibited the toxicity of either ascorbate alone or ascorbate following iron sucrose. These observations support the hypothesis that increasing intracellular labile iron pools, using iron sucrose, can be used to increase the toxicity of pharmacological ascorbate in human colon cancer cells by a mechanism involving increased generation of H2O2.
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Affiliation(s)
- Kristin E Brandt
- Free Radical and Radiation Biology Program, Departments of Radiation Oncology, Carver College of Medicine, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, United States
| | - Kelly C Falls
- Free Radical and Radiation Biology Program, Departments of Radiation Oncology, Carver College of Medicine, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, United States
| | - Joshua D Schoenfeld
- Free Radical and Radiation Biology Program, Departments of Radiation Oncology, Carver College of Medicine, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, United States
| | - Samuel N Rodman
- Free Radical and Radiation Biology Program, Departments of Radiation Oncology, Carver College of Medicine, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, United States
| | - Zhimin Gu
- Department of Internal Medicine, Carver College of Medicine, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, United States
| | - Fenghuang Zhan
- Department of Internal Medicine, Carver College of Medicine, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, United States
| | - Joseph J Cullen
- Free Radical and Radiation Biology Program, Departments of Radiation Oncology, Carver College of Medicine, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, United States; Department of Surgery, Carver College of Medicine, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, United States
| | - Brett A Wagner
- Free Radical and Radiation Biology Program, Departments of Radiation Oncology, Carver College of Medicine, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, United States
| | - Garry R Buettner
- Free Radical and Radiation Biology Program, Departments of Radiation Oncology, Carver College of Medicine, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, United States
| | - Bryan G Allen
- Free Radical and Radiation Biology Program, Departments of Radiation Oncology, Carver College of Medicine, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, United States
| | - Daniel J Berg
- Department of Internal Medicine, Carver College of Medicine, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, United States
| | - Douglas R Spitz
- Free Radical and Radiation Biology Program, Departments of Radiation Oncology, Carver College of Medicine, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, United States.
| | - Melissa A Fath
- Free Radical and Radiation Biology Program, Departments of Radiation Oncology, Carver College of Medicine, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, United States.
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24
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Schoenfeld JD, Sibenaller ZA, Mapuskar KA, Wagner BA, Cramer-Morales KL, Furqan M, Sandhu S, Carlisle TL, Smith MC, Abu Hejleh T, Berg DJ, Zhang J, Keech J, Parekh KR, Bhatia S, Monga V, Bodeker KL, Ahmann L, Vollstedt S, Brown H, Kauffman EPS, Schall ME, Hohl RJ, Clamon GH, Greenlee JD, Howard MA, Schultz MK, Smith BJ, Riley DP, Domann FE, Cullen JJ, Buettner GR, Buatti JM, Spitz DR, Allen BG. O 2⋅- and H 2O 2-Mediated Disruption of Fe Metabolism Causes the Differential Susceptibility of NSCLC and GBM Cancer Cells to Pharmacological Ascorbate. Cancer Cell 2017; 32:268. [PMID: 28810149 DOI: 10.1016/j.ccell.2017.07.008] [Citation(s) in RCA: 75] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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25
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Schoenfeld JD, Sibenaller ZA, Mapuskar KA, Wagner BA, Cramer-Morales KL, Furqan M, Sandhu S, Carlisle TL, Smith MC, Abu Hejleh T, Berg DJ, Zhang J, Keech J, Parekh KR, Bhatia S, Monga V, Bodeker KL, Ahmann L, Vollstedt S, Brown H, Shanahan Kauffman EP, Schall ME, Hohl RJ, Clamon GH, Greenlee JD, Howard MA, Schultz MK, Smith BJ, Riley DP, Domann FE, Cullen JJ, Buettner GR, Buatti JM, Spitz DR, Allen BG. O 2⋅- and H 2O 2-Mediated Disruption of Fe Metabolism Causes the Differential Susceptibility of NSCLC and GBM Cancer Cells to Pharmacological Ascorbate. Cancer Cell 2017; 31:487-500.e8. [PMID: 28366679 PMCID: PMC5497844 DOI: 10.1016/j.ccell.2017.02.018] [Citation(s) in RCA: 255] [Impact Index Per Article: 36.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Revised: 12/13/2016] [Accepted: 02/27/2017] [Indexed: 01/10/2023]
Abstract
Pharmacological ascorbate has been proposed as a potential anti-cancer agent when combined with radiation and chemotherapy. The anti-cancer effects of ascorbate are hypothesized to involve the autoxidation of ascorbate leading to increased steady-state levels of H2O2; however, the mechanism(s) for cancer cell-selective toxicity remain unknown. The current study shows that alterations in cancer cell mitochondrial oxidative metabolism resulting in increased levels of O2⋅- and H2O2 are capable of disrupting intracellular iron metabolism, thereby selectively sensitizing non-small-cell lung cancer (NSCLC) and glioblastoma (GBM) cells to ascorbate through pro-oxidant chemistry involving redox-active labile iron and H2O2. In addition, preclinical studies and clinical trials demonstrate the feasibility, selective toxicity, tolerability, and potential efficacy of pharmacological ascorbate in GBM and NSCLC therapy.
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Affiliation(s)
- Joshua D Schoenfeld
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Zita A Sibenaller
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Kranti A Mapuskar
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Brett A Wagner
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Kimberly L Cramer-Morales
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Muhammad Furqan
- Division of Hematology, Oncology, and Blood & Marrow Transplantation, Department of Internal Medicine, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Sonia Sandhu
- Division of Hematology, Oncology, and Blood & Marrow Transplantation, Department of Internal Medicine, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Thomas L Carlisle
- Division of Hematology, Oncology, and Blood & Marrow Transplantation, Department of Internal Medicine, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Mark C Smith
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Taher Abu Hejleh
- Division of Hematology, Oncology, and Blood & Marrow Transplantation, Department of Internal Medicine, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Daniel J Berg
- Division of Hematology, Oncology, and Blood & Marrow Transplantation, Department of Internal Medicine, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Jun Zhang
- Division of Hematology, Oncology, and Blood & Marrow Transplantation, Department of Internal Medicine, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - John Keech
- Department of Surgery, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Kalpaj R Parekh
- Department of Surgery, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Sudershan Bhatia
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Varun Monga
- Division of Hematology, Oncology, and Blood & Marrow Transplantation, Department of Internal Medicine, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Kellie L Bodeker
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Logan Ahmann
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Sandy Vollstedt
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Heather Brown
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Erin P Shanahan Kauffman
- Division of Hematology, Oncology, and Blood & Marrow Transplantation, Department of Internal Medicine, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Mary E Schall
- Division of Hematology, Oncology, and Blood & Marrow Transplantation, Department of Internal Medicine, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Ray J Hohl
- Division of Hematology, Oncology, and Blood & Marrow Transplantation, Department of Internal Medicine, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Gerald H Clamon
- Division of Hematology, Oncology, and Blood & Marrow Transplantation, Department of Internal Medicine, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Jeremy D Greenlee
- Department of Neurosurgery, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Matthew A Howard
- Department of Neurosurgery, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Michael K Schultz
- Department of Radiology, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Brian J Smith
- Departmet of Biostatistics, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | | | - Frederick E Domann
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Joseph J Cullen
- Department of Surgery, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Garry R Buettner
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - John M Buatti
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Douglas R Spitz
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA.
| | - Bryan G Allen
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA.
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26
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Kumar P, Bulk M, Webb A, van der Weerd L, Oosterkamp TH, Huber M, Bossoni L. A novel approach to quantify different iron forms in ex-vivo human brain tissue. Sci Rep 2016; 6:38916. [PMID: 27941952 PMCID: PMC5150947 DOI: 10.1038/srep38916] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Accepted: 11/14/2016] [Indexed: 01/28/2023] Open
Abstract
We propose a novel combination of methods to study the physical properties of ferric ions and iron-oxide nanoparticles in post-mortem human brain, based on the combination of Electron Paramagnetic Resonance (EPR) and SQUID magnetometry. By means of EPR, we derive the concentration of the low molecular weight iron pool, as well as the product of its electron spin relaxation times. Additionally, by SQUID magnetometry we identify iron mineralization products ascribable to a magnetite/maghemite phase and a ferrihydrite (ferritin) phase. We further derive the concentration of magnetite/maghemite and of ferritin nanoparticles. To test out the new combined methodology, we studied brain tissue of an Alzheimer’s patient and a healthy control. Finally, we estimate that the size of the magnetite/maghemite nanoparticles, whose magnetic moments are blocked at room temperature, exceeds 40–50 nm, which is not compatible with the ferritin protein, the core of which is typically 6–8 nm. We believe that this methodology could be beneficial in the study of neurodegenerative diseases such as Alzheimer’s Disease which are characterized by abnormal iron accumulation in the brain.
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Affiliation(s)
- Pravin Kumar
- Huygens-Kamerlingh Onnes Laboratory, Leiden University, 2333 CA Leiden, The Netherlands
| | - Marjolein Bulk
- Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands.,Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Andrew Webb
- Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands
| | - Louise van der Weerd
- Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands.,Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Tjerk H Oosterkamp
- Huygens-Kamerlingh Onnes Laboratory, Leiden University, 2333 CA Leiden, The Netherlands
| | - Martina Huber
- Huygens-Kamerlingh Onnes Laboratory, Leiden University, 2333 CA Leiden, The Netherlands
| | - Lucia Bossoni
- Huygens-Kamerlingh Onnes Laboratory, Leiden University, 2333 CA Leiden, The Netherlands
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27
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Glutamyl cysteine dipeptide suppresses ferritin expression and alleviates liver injury in iron-overload rat model. Biochimie 2015; 115:203-11. [DOI: 10.1016/j.biochi.2015.06.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Accepted: 06/09/2015] [Indexed: 12/12/2022]
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28
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Du J, Cieslak JA, Welsh JL, Sibenaller ZA, Allen BG, Wagner BA, Kalen AL, Doskey CM, Strother RK, Button AM, Mott SL, Smith B, Tsai S, Mezhir J, Goswami PC, Spitz DR, Buettner GR, Cullen JJ. Pharmacological Ascorbate Radiosensitizes Pancreatic Cancer. Cancer Res 2015; 75:3314-26. [PMID: 26081808 DOI: 10.1158/0008-5472.can-14-1707] [Citation(s) in RCA: 79] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Accepted: 05/20/2015] [Indexed: 02/03/2023]
Abstract
The toxicity of pharmacologic ascorbate is mediated by the generation of H2O2 via the oxidation of ascorbate. Because pancreatic cancer cells are sensitive to H2O2 generated by ascorbate, they would also be expected to become sensitized to agents that increase oxidative damage such as ionizing radiation. The current study demonstrates that pharmacologic ascorbate enhances the cytotoxic effects of ionizing radiation as seen by decreased cell viability and clonogenic survival in all pancreatic cancer cell lines examined, but not in nontumorigenic pancreatic ductal epithelial cells. Ascorbate radiosensitization was associated with an increase in oxidative stress-induced DNA damage, which was reversed by catalase. In mice with established heterotopic and orthotopic pancreatic tumor xenografts, pharmacologic ascorbate combined with ionizing radiation decreased tumor growth and increased survival, without damaging the gastrointestinal tract or increasing systemic changes in parameters indicative of oxidative stress. Our results demonstrate the potential clinical utility of pharmacologic ascorbate as a radiosensitizer in the treatment of pancreatic cancer.
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Affiliation(s)
- Juan Du
- Department of Surgery, University of Iowa College of Medicine, Iowa City, Iowa
| | - John A Cieslak
- Department of Radiation Oncology, University of Iowa College of Medicine, Iowa City, Iowa
| | - Jessemae L Welsh
- Department of Surgery, University of Iowa College of Medicine, Iowa City, Iowa
| | - Zita A Sibenaller
- Department of Radiation Oncology, University of Iowa College of Medicine, Iowa City, Iowa
| | - Bryan G Allen
- Department of Surgery, University of Iowa College of Medicine, Iowa City, Iowa. Holden Comprehensive Cancer Center, Iowa City, Iowa
| | - Brett A Wagner
- Department of Radiation Oncology, University of Iowa College of Medicine, Iowa City, Iowa
| | - Amanda L Kalen
- Department of Radiation Oncology, University of Iowa College of Medicine, Iowa City, Iowa
| | - Claire M Doskey
- Department of Radiation Oncology, University of Iowa College of Medicine, Iowa City, Iowa
| | - Robert K Strother
- Department of Radiation Oncology, University of Iowa College of Medicine, Iowa City, Iowa
| | | | - Sarah L Mott
- Holden Comprehensive Cancer Center, Iowa City, Iowa
| | - Brian Smith
- Holden Comprehensive Cancer Center, Iowa City, Iowa
| | - Susan Tsai
- Medical College of Wisconsin, Milwaukee, Wisconsin
| | - James Mezhir
- Department of Surgery, University of Iowa College of Medicine, Iowa City, Iowa. Holden Comprehensive Cancer Center, Iowa City, Iowa
| | - Prabhat C Goswami
- Department of Radiation Oncology, University of Iowa College of Medicine, Iowa City, Iowa. Holden Comprehensive Cancer Center, Iowa City, Iowa
| | - Douglas R Spitz
- Department of Radiation Oncology, University of Iowa College of Medicine, Iowa City, Iowa. Holden Comprehensive Cancer Center, Iowa City, Iowa
| | - Garry R Buettner
- Department of Radiation Oncology, University of Iowa College of Medicine, Iowa City, Iowa. Holden Comprehensive Cancer Center, Iowa City, Iowa
| | - Joseph J Cullen
- Department of Surgery, University of Iowa College of Medicine, Iowa City, Iowa. Department of Radiation Oncology, University of Iowa College of Medicine, Iowa City, Iowa. Holden Comprehensive Cancer Center, Iowa City, Iowa. Veterans Affairs Medical Center, Iowa City, Iowa.
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29
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Cieslak JA, Strother RK, Rawal M, Du J, Doskey CM, Schroeder SR, Button A, Wagner BA, Buettner GR, Cullen JJ. Manganoporphyrins and ascorbate enhance gemcitabine cytotoxicity in pancreatic cancer. Free Radic Biol Med 2015; 83:227-37. [PMID: 25725418 PMCID: PMC4441864 DOI: 10.1016/j.freeradbiomed.2015.02.018] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Revised: 01/23/2015] [Accepted: 02/16/2015] [Indexed: 12/17/2022]
Abstract
Pharmacological ascorbate (AscH(-)) selectively induces cytotoxicity in pancreatic cancer cells vs normal cells via the generation of extracellular hydrogen peroxide (H2O2), producing double-stranded DNA breaks and ultimately cell death. Catalytic manganoporphyrins (MnPs) can enhance ascorbate-induced cytotoxicity by increasing the rate of AscH(-) oxidation and therefore the rate of generation of H2O2. We hypothesized that combining MnPs and AscH(-) with the chemotherapeutic agent gemcitabine would further enhance pancreatic cancer cell cytotoxicity without increasing toxicity in normal pancreatic cells or other organs. Redox-active MnPs were combined with AscH(-) and administered with or without gemcitabine to human pancreatic cancer cell lines, as well as immortalized normal pancreatic ductal epithelial cells. The MnPs MnT2EPyP (Mn(III)meso-tetrakis(N-ethylpyridinium-2-yl) porphyrin pentachloride) and MnT4MPyP (Mn(III)tetrakis(N-methylpyridinium-4-yl) porphyrin pentachloride) were investigated. Clonogenic survival was significantly decreased in all pancreatic cancer cell lines studied when treated with MnP + AscH(-) + gemcitabine, whereas nontumorigenic cells were resistant. The concentration of ascorbate radical (Asc(•-), an indicator of oxidative flux) was significantly increased in treatment groups containing MnP and AscH(-). Furthermore, MnP + AscH(-) increased double-stranded DNA breaks in gemcitabine-treated cells. These results were abrogated by extracellular catalase, further supporting the role of the flux of H2O2. In vivo growth was inhibited and survival increased in mice treated with MnT2EPyP, AscH(-), and gemcitabine without a concomitant increase in systemic oxidative stress. These data suggest a promising role for the use of MnPs in combination with pharmacologic AscH(-) and chemotherapeutics in pancreatic cancer.
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Affiliation(s)
- John A Cieslak
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa College of Medicine, Iowa City, IA 52242, USA; Department of Surgery, University of Iowa College of Medicine, Iowa City, IA 52242, USA
| | - Robert K Strother
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa College of Medicine, Iowa City, IA 52242, USA
| | - Malvika Rawal
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa College of Medicine, Iowa City, IA 52242, USA
| | - Juan Du
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa College of Medicine, Iowa City, IA 52242, USA
| | - Claire M Doskey
- Interdisciplinary Program in Human Toxicology, University of Iowa, Iowa City, IA 52242, USA
| | - Samuel R Schroeder
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa College of Medicine, Iowa City, IA 52242, USA
| | - Anna Button
- Holden Comprehensive Cancer Center, Iowa City, IA 52242, USA
| | - Brett A Wagner
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa College of Medicine, Iowa City, IA 52242, USA
| | - Garry R Buettner
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa College of Medicine, Iowa City, IA 52242, USA; Holden Comprehensive Cancer Center, Iowa City, IA 52242, USA
| | - Joseph J Cullen
- Department of Surgery, University of Iowa College of Medicine, Iowa City, IA 52242, USA; Holden Comprehensive Cancer Center, Iowa City, IA 52242, USA; Veterans Affairs Medical Center, Iowa City, IA 52242, USA.
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30
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Bresgen N, Eckl PM. Oxidative stress and the homeodynamics of iron metabolism. Biomolecules 2015; 5:808-47. [PMID: 25970586 PMCID: PMC4496698 DOI: 10.3390/biom5020808] [Citation(s) in RCA: 148] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2014] [Revised: 04/21/2015] [Accepted: 04/22/2015] [Indexed: 12/12/2022] Open
Abstract
Iron and oxygen share a delicate partnership since both are indispensable for survival, but if the partnership becomes inadequate, this may rapidly terminate life. Virtually all cell components are directly or indirectly affected by cellular iron metabolism, which represents a complex, redox-based machinery that is controlled by, and essential to, metabolic requirements. Under conditions of increased oxidative stress—i.e., enhanced formation of reactive oxygen species (ROS)—however, this machinery may turn into a potential threat, the continued requirement for iron promoting adverse reactions such as the iron/H2O2-based formation of hydroxyl radicals, which exacerbate the initial pro-oxidant condition. This review will discuss the multifaceted homeodynamics of cellular iron management under normal conditions as well as in the context of oxidative stress.
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Affiliation(s)
- Nikolaus Bresgen
- Department of Cell Biology, University of Salzburg, Hellbrunnerstrasse 34, 5020 Salzburg, Austria.
| | - Peter M Eckl
- Department of Cell Biology, University of Salzburg, Hellbrunnerstrasse 34, 5020 Salzburg, Austria.
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Grasso C, Fabre MS, Collis SV, Castro ML, Field CS, Schleich N, McConnell MJ, Herst PM. Pharmacological doses of daily ascorbate protect tumors from radiation damage after a single dose of radiation in an intracranial mouse glioma model. Front Oncol 2014; 4:356. [PMID: 25566497 PMCID: PMC4266032 DOI: 10.3389/fonc.2014.00356] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2014] [Accepted: 11/27/2014] [Indexed: 12/21/2022] Open
Abstract
Pharmacological ascorbate is currently used as an anti-cancer treatment, potentially in combination with radiation therapy, by integrative medicine practitioners. In the acidic, metal-rich tumor environment, ascorbate acts as a pro-oxidant, with a mode of action similar to that of ionizing radiation; both treatments kill cells predominantly by free radical-mediated DNA damage. The brain tumor, glioblastoma multiforme (GBM), is very resistant to radiation; radiosensitizing GBM cells will improve survival of GBM patients. Here, we demonstrate that a single fraction (6 Gy) of radiation combined with a 1 h exposure to ascorbate (5 mM) sensitized murine glioma GL261 cells to radiation in survival and colony-forming assays in vitro. In addition, we report the effect of a single fraction (4.5 Gy) of whole brain radiation combined with daily intraperitoneal injections of ascorbate (1 mg/kg) in an intracranial GL261 glioma mouse model. Tumor-bearing C57BL/6 mice were divided into four groups: one group received a single dose of 4.5 Gy to the brain 8 days after tumor implantation, a second group received daily intraperitoneal injections of ascorbate (day 8-45) after implantation, a third group received both treatments and a fourth control group received no treatment. While radiation delayed tumor progression, intraperitoneal ascorbate alone had no effect on tumor progression. Tumor progression was faster in tumor-bearing mice treated with radiation and daily ascorbate than in those treated with radiation alone. Histological analysis showed less necrosis in tumors treated with both radiation and ascorbate, consistent with a radio-protective effect of ascorbate in vivo. Discrepancies between our in vitro and in vivo results may be explained by differences in the tumor microenvironment, which determines whether ascorbate remains outside the cell, acting as a pro-oxidant, or whether it enters the cells and acts as an anti-oxidant.
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Affiliation(s)
- Carole Grasso
- Malaghan Institute of Medical Research , Wellington , New Zealand
| | - Marie-Sophie Fabre
- School of Biological Sciences, Victoria University , Wellington , New Zealand
| | - Sarah V Collis
- School of Biological Sciences, Victoria University , Wellington , New Zealand
| | - M Leticia Castro
- School of Biological Sciences, Victoria University , Wellington , New Zealand
| | - Cameron S Field
- Malaghan Institute of Medical Research , Wellington , New Zealand ; School of Biological Sciences, Victoria University , Wellington , New Zealand
| | - Nanette Schleich
- Department of Radiation Therapy, University of Otago , Wellington , New Zealand
| | - Melanie J McConnell
- Malaghan Institute of Medical Research , Wellington , New Zealand ; School of Biological Sciences, Victoria University , Wellington , New Zealand
| | - Patries M Herst
- Malaghan Institute of Medical Research , Wellington , New Zealand ; Department of Radiation Therapy, University of Otago , Wellington , New Zealand
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Zhang C, Zhang F. Iron homeostasis and tumorigenesis: molecular mechanisms and therapeutic opportunities. Protein Cell 2014; 6:88-100. [PMID: 25476483 PMCID: PMC4312762 DOI: 10.1007/s13238-014-0119-z] [Citation(s) in RCA: 99] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2014] [Accepted: 11/04/2014] [Indexed: 12/21/2022] Open
Abstract
Excess iron is tightly associated with tumorigenesis in multiple human cancer types through a variety of mechanisms including catalyzing the formation of mutagenic hydroxyl radicals, regulating DNA replication, repair and cell cycle progression, affecting signal transduction in cancer cells, and acting as an essential nutrient for proliferating tumor cells. Thus, multiple therapeutic strategies based on iron deprivation have been developed in cancer therapy. During the past few years, our understanding of genetic association and molecular mechanisms between iron and tumorigenesis has expanded enormously. In this review, we briefly summarize iron homeostasis in mammals, and discuss recent progresses in understanding the aberrant iron metabolism in numerous cancer types, with a focus on studies revealing altered signal transduction in cancer cells.
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Affiliation(s)
- Caiguo Zhang
- Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Aurora, CO, 80045, USA,
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