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Vaishampayan P, Lee Y. Redox-active vitamin C suppresses human osteosarcoma growth by triggering intracellular ROS-iron-calcium signaling crosstalk and mitochondrial dysfunction. Redox Biol 2024; 75:103288. [PMID: 39083898 DOI: 10.1016/j.redox.2024.103288] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2024] [Accepted: 07/26/2024] [Indexed: 08/02/2024] Open
Abstract
Pharmacological vitamin C (VC) has gained attention for its pro-oxidant characteristics and selective ability to induce cancer cell death. However, defining its role in cancer has been challenging due to its complex redox properties. In this study, using a human osteosarcoma (OS) model, we show that the redox-active property of VC is critical for inducing non-apoptotic cancer cell death via intracellular reactive oxygen species (ROS)-iron-calcium crosstalk and mitochondrial dysfunction. In both 2D and 3D OS cell culture models, only the oxidizable form of VC demonstrated potent dose-dependent cytotoxicity, while non-oxidizable and oxidized VC derivatives had minimal effects. Live-cell imaging showed that only oxidizable VC caused a surge in cytotoxic ROS, dependent on iron rather than copper. Inhibitors of ferroptosis, a form of iron-dependent cell death, along with classical apoptosis inhibitors, were unable to completely counteract the cytotoxic effects induced by VC. Further pharmacological and genetic inhibition analyses showed that VC triggers calcium release through inositol 1,4,5-trisphosphate receptors (IP3Rs), leading to mitochondrial ROS production and eventual cell death. RNA sequencing revealed down-regulation of genes involved in the mitochondrial electron transport chain and oxidative phosphorylation upon pharmacological VC treatment. Consistently, high-dose VC reduced mitochondrial membrane potential, oxidative phosphorylation, and ATP levels, with ATP reconstitution rescuing VC-induced cytotoxicity. In vivo OS xenograft studies demonstrated reduced tumor growth with high-dose VC administration, concomitant with the altered expression of mitochondrial ATP synthase (MT-ATP). These findings emphasize VC's potential clinical utility in osteosarcoma treatment by inducing mitochondrial metabolic dysfunction through a vicious intracellular ROS-iron-calcium cycle.
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Affiliation(s)
- Prajakta Vaishampayan
- Department of Translational Medicine and Physiology, Elson S. Floyd College of Medicine, Washington State University, Spokane, WA, 99202, USA
| | - Yool Lee
- Department of Translational Medicine and Physiology, Elson S. Floyd College of Medicine, Washington State University, Spokane, WA, 99202, USA; Department of Integrative Physiology and Neuroscience, College of Veterinary Medicine, Washington State University, Pullman, WA, 99164, USA; Sleep and Performance Research Center, Washington State University, Spokane, WA, 99202, USA; Steve Gleason Institute for Neuroscience, Washington State University, Spokane, WA, 99202, USA.
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2
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Yi Z, Yang X, Liang Y, Tong S. Iron oxide nanozymes enhanced by ascorbic acid for macrophage-based cancer therapy. NANOSCALE 2024. [PMID: 39015956 DOI: 10.1039/d4nr01208a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/18/2024]
Abstract
In recent years, using pharmacological ascorbic acid has emerged as a promising therapeutic approach in cancer treatment, owing to its capacity to induce extracellular hydrogen peroxide (H2O2) production in solid tumors. The H2O2 is then converted into cytotoxic hydroxyl free radicals (HO˙) by redox-active Fe2+ inside cells. However, the high dosage of ascorbic acid required for efficacy is hampered by adverse effects such as kidney stone formation. In a recent study, we demonstrated the efficient catalytic conversion of H2O2 to HO˙ by wüstite (Fe1-xO) nanoparticles (WNPs) through a heterogenous Fenton reaction. Here, we explore whether WNPs can enhance the therapeutic potential of ascorbic acid, thus mitigating its dose-related limitations. Our findings reveal distinct pH dependencies for WNPs and ascorbic acid in the Fenton reaction and H2O2 generation, respectively. Importantly, WNPs exhibit the capability to either impede or enhance the cytotoxic effect of ascorbic acid, depending on the spatial segregation of the two reagents by cellular compartments. Furthermore, our study demonstrates that treatment with ascorbic acid promotes the polarization of WNP-loaded macrophages toward a pro-inflammatory M1 phenotype, significantly suppressing the growth of 4T1 breast cancer cells. This study highlights the importance of orchestrating the interplay between ascorbic acid and nanozymes in cancer therapy and presents a novel macrophage-based cell therapy approach.
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Affiliation(s)
- Zhongchao Yi
- Department of Biomedical Engineering, University of Kentucky, Lexington, Kentucky 40536, USA.
| | - Xiaoyue Yang
- Department of Biomedical Engineering, University of Kentucky, Lexington, Kentucky 40536, USA.
| | - Ying Liang
- New York Blood Center, New York, New York 10065, USA
| | - Sheng Tong
- Department of Biomedical Engineering, University of Kentucky, Lexington, Kentucky 40536, USA.
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3
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Onciul R, Brehar FM, Toader C, Covache-Busuioc RA, Glavan LA, Bratu BG, Costin HP, Dumitrascu DI, Serban M, Ciurea AV. Deciphering Glioblastoma: Fundamental and Novel Insights into the Biology and Therapeutic Strategies of Gliomas. Curr Issues Mol Biol 2024; 46:2402-2443. [PMID: 38534769 DOI: 10.3390/cimb46030153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Revised: 03/06/2024] [Accepted: 03/09/2024] [Indexed: 03/28/2024] Open
Abstract
Gliomas constitute a diverse and complex array of tumors within the central nervous system (CNS), characterized by a wide range of prognostic outcomes and responses to therapeutic interventions. This literature review endeavors to conduct a thorough investigation of gliomas, with a particular emphasis on glioblastoma (GBM), beginning with their classification and epidemiological characteristics, evaluating their relative importance within the CNS tumor spectrum. We examine the immunological context of gliomas, unveiling the intricate immune environment and its ramifications for disease progression and therapeutic strategies. Moreover, we accentuate critical developments in understanding tumor behavior, focusing on recent research breakthroughs in treatment responses and the elucidation of cellular signaling pathways. Analyzing the most novel transcriptomic studies, we investigate the variations in gene expression patterns in glioma cells, assessing the prognostic and therapeutic implications of these genetic alterations. Furthermore, the role of epigenetic modifications in the pathogenesis of gliomas is underscored, suggesting that such changes are fundamental to tumor evolution and possible therapeutic advancements. In the end, this comparative oncological analysis situates GBM within the wider context of neoplasms, delineating both distinct and shared characteristics with other types of tumors.
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Affiliation(s)
- Razvan Onciul
- Department of Neurosurgery, "Carol Davila" University of Medicine and Pharmacy, 020021 Bucharest, Romania
- Neurosurgery Department, Emergency University Hospital, 050098 Bucharest, Romania
| | - Felix-Mircea Brehar
- Department of Neurosurgery, "Carol Davila" University of Medicine and Pharmacy, 020021 Bucharest, Romania
- Department of Neurosurgery, Clinical Emergency Hospital "Bagdasar-Arseni", 041915 Bucharest, Romania
| | - Corneliu Toader
- Department of Neurosurgery, "Carol Davila" University of Medicine and Pharmacy, 020021 Bucharest, Romania
- Department of Vascular Neurosurgery, National Institute of Neurology and Neurovascular Diseases, 077160 Bucharest, Romania
| | | | - Luca-Andrei Glavan
- Department of Neurosurgery, "Carol Davila" University of Medicine and Pharmacy, 020021 Bucharest, Romania
| | - Bogdan-Gabriel Bratu
- Department of Neurosurgery, "Carol Davila" University of Medicine and Pharmacy, 020021 Bucharest, Romania
| | - Horia Petre Costin
- Department of Neurosurgery, "Carol Davila" University of Medicine and Pharmacy, 020021 Bucharest, Romania
| | - David-Ioan Dumitrascu
- Department of Neurosurgery, "Carol Davila" University of Medicine and Pharmacy, 020021 Bucharest, Romania
| | - Matei Serban
- Department of Neurosurgery, "Carol Davila" University of Medicine and Pharmacy, 020021 Bucharest, Romania
| | - Alexandru Vlad Ciurea
- Department of Neurosurgery, "Carol Davila" University of Medicine and Pharmacy, 020021 Bucharest, Romania
- Neurosurgery Department, Sanador Clinical Hospital, 010991 Bucharest, Romania
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Petronek MS, Bodeker KL, Lee CY, Teferi N, Eschbacher KL, Jones KA, Loeffler BT, Smith BJ, Buatti JM, Magnotta VA, Allen BG. Iron-based biomarkers for personalizing pharmacological ascorbate therapy in glioblastoma: insights from a phase 2 clinical trial. J Neurooncol 2024; 166:493-501. [PMID: 38285244 DOI: 10.1007/s11060-024-04571-z] [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: 12/08/2023] [Accepted: 01/11/2024] [Indexed: 01/30/2024]
Abstract
BACKGROUND Pharmacological ascorbate (intravenous delivery reaching plasma concentrations ≈ 20 mM; P-AscH-) has emerged as a promising therapeutic strategy for glioblastoma. Recently, a single-arm phase 2 clinical trial demonstrated a significant increase in overall survival when P-AscH- was combined with temozolomide and radiotherapy. As P-AscH- relies on iron-dependent mechanisms, this study aimed to assess the predictive potential of both molecular and imaging-based iron-related markers to enhance the personalization of P-AscH- therapy in glioblastoma participants. METHODS Participants (n = 55) with newly diagnosed glioblastoma were enrolled in a phase 2 clinical trial conducted at the University of Iowa (NCT02344355). Tumor samples obtained during surgical resection were processed and stained for transferrin receptor and ferritin heavy chain expression. A blinded pathologist performed pathological assessment. Quantitative susceptibility mapping (QSM) measures were obtained from pre-radiotherapy MRI scans following maximal safe surgical resection. Circulating blood iron panels were evaluated prior to therapy through the University of Iowa Diagnostic Laboratory. RESULTS Through univariate analysis, a significant inverse association was observed between tumor transferrin receptor expression and overall and progression-free survival. QSM measures exhibited a significant, positive association with progression-free survival. Subjects were actively followed until disease progression and then were followed through chart review or clinical visits for overall survival. CONCLUSIONS This study analyzes iron-related biomarkers in the context of P-AscH- therapy for glioblastoma. Integrating molecular, systemic, and imaging-based markers offers a multifaceted approach to tailoring treatment strategies, thereby contributing to improved patient outcomes and advancing the field of glioblastoma therapy.
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Affiliation(s)
- M S Petronek
- Department of Radiation Oncology, Division of Free Radical and Radiation Biology, University of Iowa, Iowa City, IA, USA.
| | - K L Bodeker
- Department of Radiation Oncology, Division of Free Radical and Radiation Biology, University of Iowa, Iowa City, IA, USA
| | - C Y Lee
- Department of Radiology, University of Iowa, Iowa City, IA, USA
| | - N Teferi
- Department of Radiation Oncology, Division of Free Radical and Radiation Biology, University of Iowa, Iowa City, IA, USA
| | - K L Eschbacher
- Department of Pathology, University of Iowa, Iowa City, IA, USA
| | - K A Jones
- Department of Pathology, Division of Neuropathology, Duke University, Durham, NC, USA
| | - B T Loeffler
- Holden Comprehensive Cancer Center, University of Iowa, Iowa City, IA, USA
| | - B J Smith
- Department of Biostatistics, University of Iowa, Iowa City, IA, USA
| | - J M Buatti
- Department of Radiation Oncology, Division of Free Radical and Radiation Biology, 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, Division of Free Radical and Radiation Biology, University of Iowa, Iowa City, IA, USA
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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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Petronek MS, Teferi N, Lee CY, Magnotta VA, Allen BG. MRI Detection and Therapeutic Enhancement of Ferumoxytol Internalization in Glioblastoma Cells. NANOMATERIALS (BASEL, SWITZERLAND) 2024; 14:189. [PMID: 38251153 PMCID: PMC10821426 DOI: 10.3390/nano14020189] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2023] [Revised: 01/11/2024] [Accepted: 01/12/2024] [Indexed: 01/23/2024]
Abstract
Recently, the FDA-approved iron oxide nanoparticle, ferumoxytol, has been found to enhance the efficacy of pharmacological ascorbate (AscH-) in treating glioblastoma, as AscH- reduces the Fe3+ sites in the nanoparticle core. Given the iron oxidation state specificity of T2* relaxation mapping, this study aims to investigate the ability of T2* relaxation to monitor the reduction of ferumoxytol by AscH- with respect to its in vitro therapeutic enhancement. This study employed an in vitro glioblastoma MRI model system to investigate the chemical interaction of ferumoxytol with T2* mapping. Lipofectamine was utilized to facilitate ferumoxytol internalization and assess intracellular versus extracellular chemistry. In vitro T2* mapping successfully detected an AscH--mediated reduction of ferumoxytol (25.6 ms versus 2.8 ms for FMX alone). The T2* relaxation technique identified the release of Fe2+ from ferumoxytol by AscH- in glioblastoma cells. However, the high iron content of ferumoxytol limited T2* ability to differentiate between the external and internal reduction of ferumoxytol by AscH- (ΔT2* = +839% for external FMX and +1112% for internal FMX reduction). Notably, the internalization of ferumoxytol significantly enhances its ability to promote AscH- toxicity (dose enhancement ratio for extracellular FMX = 1.16 versus 1.54 for intracellular FMX). These data provide valuable insights into the MR-based nanotheranostic application of ferumoxytol and AscH- therapy for glioblastoma management. Future developmental efforts, such as FMX surface modifications, may be warranted to enhance this approach further.
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Affiliation(s)
- Michael S. Petronek
- Department of Radiation Oncology, University of Iowa, Iowa City, IA 52242, USA
| | - Nahom Teferi
- Department of Neurosurgery, University of Iowa, Iowa City, IA 52242, USA;
| | - Chu-Yu Lee
- Department of Radiology, University of Iowa, Iowa City, IA 52242, USA (V.A.M.)
| | - Vincent A. Magnotta
- Department of Radiology, University of Iowa, Iowa City, IA 52242, USA (V.A.M.)
| | - Bryan G. Allen
- Department of Radiation Oncology, University of Iowa, Iowa City, IA 52242, USA
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Xiao W, Zhao L, Sun Y, Yang X, Fu Q. Stimuli-Responsive Nanoradiosensitizers for Enhanced Cancer Radiotherapy. SMALL METHODS 2024; 8:e2301131. [PMID: 37906050 DOI: 10.1002/smtd.202301131] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Revised: 10/10/2023] [Indexed: 11/02/2023]
Abstract
Radiotherapy (RT) has been a classical therapeutic method of cancer for several decades. It attracts tremendous attention for the precise and efficient treatment of local tumors with stimuli-responsive nanomaterials, which enhance RT. However, there are few systematic reviews summarizing the newly emerging stimuli-responsive mechanisms and strategies used for tumor radio-sensitization. Hence, this review provides a comprehensive overview of recently reported studies on stimuli-responsive nanomaterials for radio-sensitization. It includes four different approaches for sensitized RT, namely endogenous response, exogenous response, dual stimuli-response, and multi stimuli-response. Endogenous response involves various stimuli such as pH, hypoxia, GSH, and reactive oxygen species (ROS), and enzymes. On the other hand, exogenous response encompasses X-ray, light, and ultrasound. Dual stimuli-response combines pH/enzyme, pH/ultrasound, and ROS/light. Lastly, multi stimuli-response involves the combination of pH/ROS/GSH and X-ray/ROS/GSH. By elaborating on these responsive mechanisms and applying them to clinical RT diagnosis and treatment, these methods can enhance radiosensitive efficiency and minimize damage to surrounding normal tissues. Finally, this review discusses the additional challenges and perspectives related to stimuli-responsive nanomaterials for tumor radio-sensitization.
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Affiliation(s)
- Wenjing Xiao
- Department of Radiotherapy, The Affiliated Hospital of Qingdao University, Qingdao University, Qingdao, 266021, China
| | - Lin Zhao
- Department of Radiotherapy, The Affiliated Hospital of Qingdao University, Qingdao University, Qingdao, 266021, China
- Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, College of Medicine, Qingdao University, Qingdao, 266021, China
| | - Yang Sun
- Department of Radiotherapy, The Affiliated Hospital of Qingdao University, Qingdao University, Qingdao, 266021, China
| | - Xiao Yang
- Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, College of Medicine, Qingdao University, Qingdao, 266021, China
| | - Qinrui Fu
- Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, College of Medicine, Qingdao University, Qingdao, 266021, China
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Zaher A, Mapuskar KA, Sarkaria JN, Spitz DR, Petronek MS, Allen BG. Differential H 2O 2 Metabolism among Glioblastoma Subtypes Confers Variable Responses to Pharmacological Ascorbate Therapy Combined with Chemoradiation. Int J Mol Sci 2023; 24:17158. [PMID: 38138986 PMCID: PMC10743151 DOI: 10.3390/ijms242417158] [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: 11/02/2023] [Revised: 11/29/2023] [Accepted: 12/04/2023] [Indexed: 12/24/2023] Open
Abstract
Glioblastoma (GBM), a highly lethal and aggressive central nervous system malignancy, presents a critical need for targeted therapeutic approaches to improve patient outcomes in conjunction with standard-of-care (SOC) treatment. Molecular subtyping based on genetic profiles and metabolic characteristics has advanced our understanding of GBM to better predict its evolution, mechanisms, and treatment regimens. Pharmacological ascorbate (P-AscH-) has emerged as a promising supplementary cancer therapy, leveraging its pro-oxidant properties to selectively kill malignant cells when combined with SOC. Given the clinical challenges posed by the heterogeneity and resistance of various GBM subtypes to conventional SOC, our study assessed the response of classical, mesenchymal, and proneural GBM to P-AscH-. P-AscH- (20 pmol/cell) combined with SOC (5 µM temozolomide and 4 Gy of radiation) enhanced clonogenic cell killing in classical and mesenchymal GBM subtypes, with limited effects in the proneural subtype. Similarly, following exposure to P-AscH- (20 pmol/cell), single-strand DNA damage significantly increased in classical and mesenchymal but not proneural GBM. Moreover, proneural GBM exhibited increased hydrogen peroxide removal rates, along with increased catalase and glutathione peroxidase activities compared to mesenchymal and classical GBM, demonstrating an altered H2O2 metabolism that potentially drives differential P-AscH- toxicity. Taken together, these data suggest that P-AscH- may hold promise as an approach to improve SOC responsiveness in mesenchymal GBMs that are known for their resistance to SOC.
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Affiliation(s)
- Amira Zaher
- Department of Radiation Oncology, The University of Iowa, Iowa City, IA 52242, USA; (A.Z.); (K.A.M.); (D.R.S.)
| | - Kranti A. Mapuskar
- Department of Radiation Oncology, The University of Iowa, Iowa City, IA 52242, USA; (A.Z.); (K.A.M.); (D.R.S.)
| | - Jann N. Sarkaria
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN 55905, USA;
| | - Douglas R. Spitz
- Department of Radiation Oncology, The University of Iowa, Iowa City, IA 52242, USA; (A.Z.); (K.A.M.); (D.R.S.)
| | - Michael S. Petronek
- Department of Radiation Oncology, The University of Iowa, Iowa City, IA 52242, USA; (A.Z.); (K.A.M.); (D.R.S.)
| | - Bryan G. Allen
- Department of Radiation Oncology, The University of Iowa, Iowa City, IA 52242, USA; (A.Z.); (K.A.M.); (D.R.S.)
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