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Coll RP, Bright SJ, Martinus DKJ, Georgiou DK, Sawakuchi GO, Manning HC. Alpha Particle-Emitting Radiopharmaceuticals as Cancer Therapy: Biological Basis, Current Status, and Future Outlook for Therapeutics Discovery. Mol Imaging Biol 2023; 25:991-1019. [PMID: 37845582 DOI: 10.1007/s11307-023-01857-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 09/03/2023] [Accepted: 09/05/2023] [Indexed: 10/18/2023]
Abstract
Critical advances in radionuclide therapy have led to encouraging new options for cancer treatment through the pairing of clinically useful radiation-emitting radionuclides and innovative pharmaceutical discovery. Of the various subatomic particles used in therapeutic radiopharmaceuticals, alpha (α) particles show great promise owing to their relatively large size, delivered energy, finite pathlength, and resulting ionization density. This review discusses the therapeutic benefits of α-emitting radiopharmaceuticals and their pairing with appropriate diagnostics, resulting in innovative "theranostic" platforms. Herein, the current landscape of α particle-emitting radionuclides is described with an emphasis on their use in theranostic development for cancer treatment. Commonly studied radionuclides are introduced and recent efforts towards their production for research and clinical use are described. The growing popularity of these radionuclides is explained through summarizing the biological effects of α radiation on cancer cells, which include DNA damage, activation of discrete cell death programs, and downstream immune responses. Examples of efficient α-theranostic design are described with an emphasis on strategies that lead to cellular internalization and the targeting of proteins involved in therapeutic resistance. Historical barriers to the clinical deployment of α-theranostic radiopharmaceuticals are also discussed. Recent progress towards addressing these challenges is presented along with examples of incorporating α-particle therapy in pharmaceutical platforms that can be easily converted into diagnostic counterparts.
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Affiliation(s)
- Ryan P Coll
- Department of Cancer Systems Imaging, The University of Texas MD Anderson Cancer Center, 1881 East Rd, Houston, TX, 77054, USA
| | - Scott J Bright
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, 6565 MD Anderson Blvd, Houston, TX, 77030, USA
| | - David K J Martinus
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, 6565 MD Anderson Blvd, Houston, TX, 77030, USA
| | - Dimitra K Georgiou
- Department of Cancer Systems Imaging, The University of Texas MD Anderson Cancer Center, 1881 East Rd, Houston, TX, 77054, USA
| | - Gabriel O Sawakuchi
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, 6565 MD Anderson Blvd, Houston, TX, 77030, USA
| | - H Charles Manning
- Department of Cancer Systems Imaging, The University of Texas MD Anderson Cancer Center, 1881 East Rd, Houston, TX, 77054, USA.
- Cyclotron Radiochemistry Facility, The University of Texas MD Anderson Cancer Center, 1881 East Rd, Houston, TX, 77054, USA.
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Bolcaen J, Gizawy MA, Terry SYA, Paulo A, Cornelissen B, Korde A, Engle J, Radchenko V, Howell RW. Marshalling the Potential of Auger Electron Radiopharmaceutical Therapy. J Nucl Med 2023; 64:1344-1351. [PMID: 37591544 PMCID: PMC10478825 DOI: 10.2967/jnumed.122.265039] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 07/05/2023] [Indexed: 08/19/2023] Open
Abstract
Auger electron (AE) radiopharmaceutical therapy (RPT) may have the same therapeutic efficacy as α-particles for oncologic small disease, with lower risks of normal-tissue toxicity. The seeds of using AE emitters for RPT were planted several decades ago. Much knowledge has been gathered about the potency of the biologic effects caused by the intense shower of these low-energy AEs. Given their short range, AEs deposit much of their energy in the immediate vicinity of their site of decay. However, the promise of AE RPT has not yet been realized, with few agents evaluated in clinical trials and none becoming part of routine treatment so far. Instigated by the 2022 "Technical Meeting on Auger Electron Emitters for Radiopharmaceutical Developments" at the International Atomic Energy Agency, this review presents the current status of AE RPT based on the discussions by experts in the field. A scoring system was applied to illustrate hurdles in the development of AE RPT, and we present a selected list of well-studied and emerging AE-emitting radionuclides. Based on the number of AEs and other emissions, physical half-life, radionuclide production, radiochemical approaches, dosimetry, and vector availability, recommendations are put forward to enhance and impact future efforts in AE RPT research.
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Affiliation(s)
- Julie Bolcaen
- SSC Laboratory, Radiation Biophysics, NRF iThemba LABS, Cape Town, South Africa
| | - Mohamed A Gizawy
- Egyptian Second Research Reactor Complex, Egyptian Atomic Energy Authority, Cairo, Egypt
| | - Samantha Y A Terry
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
| | - António Paulo
- Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, Campus Tecnológico e Nuclear, Bobadela, Portugal
| | - Bart Cornelissen
- Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Aruna Korde
- Division of Physical and Chemical Sciences, Department of Nuclear Sciences and Application, International Atomic Energy Agency, Vienna, Austria
| | - Jonathan Engle
- University of Wisconsin Cyclotron Research Group, Departments of Medical Physics and Radiology, Madison, Wisconsin
| | - Valery Radchenko
- TRIUMF, Life Sciences Division, Vancouver, British Columbia, Canada;
- University of British Columbia, Chemistry Department, Vancouver, British Columbia, Canada; and
| | - Roger W Howell
- Division of Radiation Research, Department of Radiology and Center for Cell Signaling, New Jersey Medical School, Rutgers University, Newark, New Jersey
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Ho PJ, Ray D, Lehmann CS, Fouda AEA, Dunford RW, Kanter EP, Doumy G, Young L, Walko DA, Zheng X, Cheng L, Southworth SH. X-ray induced electron and ion fragmentation dynamics in IBr. J Chem Phys 2023; 158:134304. [PMID: 37031139 DOI: 10.1063/5.0145215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/07/2023] Open
Abstract
Characterization of the inner-shell decay processes in molecules containing heavy elements is key to understanding x-ray damage of molecules and materials and for medical applications with Auger-electron-emitting radionuclides. The 1s hole states of heavy atoms can be produced by absorption of tunable x rays and the resulting vacancy decays characterized by recording emitted photons, electrons, and ions. The 1s hole states in heavy elements have large x-ray fluorescence yields that transfer the hole to intermediate electron shells that then decay by sequential Auger-electron transitions that increase the ion’s charge state until the final state is reached. In molecules, the charge is spread across the atomic sites, resulting in dissociation to energetic atomic ions. We have used x-ray/ion coincidence spectroscopy to measure charge states and energies of I q+ and Br q′+ atomic ions following 1s ionization at the I and Br K-edges of IBr. We present the charge states and kinetic energies of the two correlated fragment ions associated with core-excited states produced during the various steps of the cascades. To understand the dynamics leading to the ion data, we develop a computational model that combines Monte-Carlo/Molecular-Dynamics (MC/MD) simulations with a classical over-the-barrier model to track inner-shell cascades and redistribution of electrons in valence orbitals and nuclear motion of fragments.
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Affiliation(s)
- Phay J. Ho
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - Dipanwita Ray
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - C. Stefan Lehmann
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - Adam E. A. Fouda
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - Robert W. Dunford
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - Elliot P. Kanter
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - Gilles Doumy
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - Linda Young
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, USA
- The James Franck Institute and Department of Physics, The University of Chicago, Chicago, Illinois 60637, USA
| | - Donald A. Walko
- Advanced Photon Source, Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - Xuechen Zheng
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, USA
| | - Lan Cheng
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, USA
| | - Stephen H. Southworth
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, USA
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Alcocer Ávila ME, Hindié E, Champion C. How to explain the sensitivity of DNA double-strand breaks yield to 125I position? Int J Radiat Biol 2023; 99:103-108. [PMID: 35259042 DOI: 10.1080/09553002.2022.2047822] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
PURPOSE Auger emitters exhibit interesting features due to their emission of a cascade of short-range Auger electrons. Maximum DNA breakage efficacy is achieved when decays occur near DNA. Studies of double-strand breaks (DSBs) yields in plasmids revealed cutoff distances from DNA axis of 10.5 Å-12 Å, beyond which the mechanism of DSBs moves from direct to indirect effects, and the yield decreases rapidly. Some authors suggested that the average energy deposited in a DNA cylinder could explain such cutoffs. We aimed to study this hypothesis in further detail. MATERIALS AND METHODS Using the Monte Carlo code CELLDOSE, we investigated the influence of the 125I atom position on energy deposits and absorbed doses per decay not only in a DNA cylinder, but also in individual strands, each modeled as 10 spheres encompassing the fragility sites for phosphodiester bond cleavage. RESULTS The dose per decay decreased much more rapidly for a sphere in the proximal strand than for the DNA cylinder. For example, when moving the 125I source from 10.5 Å to 11.5 Å, the average dose to the sphere dropped by 43%, compared to only 13% in the case of the cylinder. CONCLUSIONS Explaining variations in DSBs yields with 125I position should consider the probability of inducing damage in the proximal strand (nearest to the 125I atom). The energy received by fragility sites in this strand is highly influenced by the isotropic (4π) emission of 125I low-energy Auger electrons. The positioning of Auger emitters for targeted radionuclide therapy can be envisioned accordingly.
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Affiliation(s)
| | - Elif Hindié
- Université de Bordeaux, INCIA, CHU de Bordeaux - Service de Médecine Nucléaire, Pessac, France.,Institut Universitaire de France (IUF), Paris, France
| | - Christophe Champion
- Université de Bordeaux-CNRS-CEA, Centre Lasers Intenses et Applications, UMR 5107, Talence, France
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Katugampola S, Wang J, Rosen A, Howell RW. MIRD Pamphlet No. 27: MIRDcell V3, a Revised Software Tool for Multicellular Dosimetry and Bioeffect Modeling. J Nucl Med 2022; 63:1441-1449. [PMID: 35145016 PMCID: PMC9454469 DOI: 10.2967/jnumed.121.263253] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 01/26/2022] [Indexed: 01/26/2023] Open
Abstract
Radiopharmaceutical therapy is growing rapidly. However, yet to be addressed is the implementation of methods to plan treatments for circulating tumor cells, disseminated tumor cells, and micrometastases. Given the capacity of radiopharmaceuticals to specifically target and kill single cells and multicellular clusters, a quality not available in chemotherapy and external-beam radiation therapy, it is important to develop dosimetry and bioeffect modeling tools that can inform radiopharmaceutical design and predict their effect on microscopic disease. This pamphlet describes a new version of MIRDcell, a software tool that was initially released by the MIRD committee several years ago. Methods: Version 3 (V3) of MIRDcell uses a combination of analytic and Monte Carlo methods to conduct dosimetry and bioeffect modeling for radiolabeled cells within planar colonies and multicellular clusters. A worked example is provided to assist users to learn old and new features of MIRDcell and test its capacity to recapitulate published responses of tumor cell spheroids to radiopharmaceutical treatments. Prominent capabilities of the new version include radially dependent activity distributions, user-imported activity distributions, cold regions within the cluster, complex bioeffect modeling that accounts for radiation type and subcellular distribution, and a rich table of output data for subsequent analysis. Results: MIRDcell V3 effectively reproduces experimental responses of multicellular spheroids to uniform and nonuniform distributions of therapeutic radiopharmaceuticals. Conclusion: MIRDcell is a versatile software tool that can be used for educational purposes and design of radiopharmaceutical therapies.
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Affiliation(s)
- Sumudu Katugampola
- Division of Radiation Research, Department of Radiology, New Jersey Medical School, Rutgers University, Newark, New Jersey
| | - Jianchao Wang
- Division of Radiation Research, Department of Radiology, New Jersey Medical School, Rutgers University, Newark, New Jersey
| | - Alex Rosen
- Division of Radiation Research, Department of Radiology, New Jersey Medical School, Rutgers University, Newark, New Jersey
| | - Roger W Howell
- Division of Radiation Research, Department of Radiology, New Jersey Medical School, Rutgers University, Newark, New Jersey
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Stokke C, Kvassheim M, Blakkisrud J. Radionuclides for Targeted Therapy: Physical Properties. Molecules 2022; 27:molecules27175429. [PMID: 36080198 PMCID: PMC9457625 DOI: 10.3390/molecules27175429] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 08/19/2022] [Accepted: 08/21/2022] [Indexed: 11/16/2022] Open
Abstract
A search in PubMed revealed that 72 radionuclides have been considered for molecular or functional targeted radionuclide therapy. As radionuclide therapies increase in number and variations, it is important to understand the role of the radionuclide and the various characteristics that can render it either useful or useless. This review focuses on the physical characteristics of radionuclides that are relevant for radionuclide therapy, such as linear energy transfer, relative biological effectiveness, range, half-life, imaging properties, and radiation protection considerations. All these properties vary considerably between radionuclides and can be optimised for specific targets. Properties that are advantageous for some applications can sometimes be drawbacks for others; for instance, radionuclides that enable easy imaging can introduce more radiation protection concerns than others. Similarly, a long radiation range is beneficial in targets with heterogeneous uptake, but it also increases the radiation dose to tissues surrounding the target, and, hence, a shorter range is likely more beneficial with homogeneous uptake. While one cannot select a collection of characteristics as each radionuclide comes with an unchangeable set, all the 72 radionuclides investigated for therapy—and many more that have not yet been investigated—provide numerous sets to choose between.
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Affiliation(s)
- Caroline Stokke
- Department of Physics and Computational Radiology, Division of Radiology and Nuclear Medicine, Oslo University Hospital, P.O. Box 4959 Nydalen, 0424 Oslo, Norway
- Department of Physics, University of Oslo, Problemveien 7, 0315 Oslo, Norway
- Correspondence:
| | - Monika Kvassheim
- Department of Physics and Computational Radiology, Division of Radiology and Nuclear Medicine, Oslo University Hospital, P.O. Box 4959 Nydalen, 0424 Oslo, Norway
- Division of Clinical Medicine, University of Oslo, Problemveien 7, 0315 Oslo, Norway
| | - Johan Blakkisrud
- Department of Physics and Computational Radiology, Division of Radiology and Nuclear Medicine, Oslo University Hospital, P.O. Box 4959 Nydalen, 0424 Oslo, Norway
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Salim R, Taherparvar P. Dosimetry assessment of theranostic Auger-emitting radionuclides in a micron-sized multicellular cluster model: A Monte Carlo study using Geant4-DNA simulations. Appl Radiat Isot 2022; 188:110380. [PMID: 35868198 DOI: 10.1016/j.apradiso.2022.110380] [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: 04/04/2022] [Revised: 06/28/2022] [Accepted: 07/07/2022] [Indexed: 11/02/2022]
Abstract
The present work is aimed at improving the multicellular dosimetry of several Auger radionuclides of interest for targeted cancer therapy, including 99mTc, 111In, 123I, 125I, and 201Tl. For this purpose, using the Geant4-DNA Monte Carlo code, a cluster of 13 similar spherical cells with a hexagonal packed arrangement was modeled, and the mean absorbed doses per unit cumulated activity (S-values) were calculated by considering two target←source configurations, cell←cell and nucleus←nucleus. The obtained ratios of cross-dose to self-dose S-value in terms of the distance between the source and target regions were evaluated and also compared to those estimated by the Medical Internal Radiation Dose (MIRD) method. Besides, the contribution of the Coster-Kronig, Auger and internal conversion electrons to the S-values was provided for each radionuclide. According to the results, it can be concluded that in contrast to self-absorption, the cross-absorption due to the Auger-emitters has not a significant role in the total energy deposition within a cell in the cluster.
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Affiliation(s)
- R Salim
- Department of Physics, Faculty of Science, University of Guilan, Rasht, Iran
| | - P Taherparvar
- Department of Physics, Faculty of Science, University of Guilan, Rasht, Iran.
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Principles and Applications of Auger-Electron Radionuclide Therapy. Nucl Med Mol Imaging 2022. [DOI: 10.1016/b978-0-12-822960-6.00040-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Li W, Kavatsyuk O, Douma W, Wang X, Hoekstra R, Mayer D, Robinson MS, Gühr M, Lalande M, Abdelmouleh M, Ryszka M, Poully JC, Schlathölter T. Multiple valence electron detachment following Auger decay of inner-shell vacancies in gas-phase DNA. Chem Sci 2021; 12:13177-13186. [PMID: 34745549 PMCID: PMC8513815 DOI: 10.1039/d1sc02885e] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Accepted: 09/10/2021] [Indexed: 01/05/2023] Open
Abstract
We have studied soft X-ray photoabsorption in the doubly deprotonated gas-phase oligonucleotide [dTGGGGT–2H]2−. The dominating decay mechanism of the X-ray induced inner shell vacancy was found to be Auger decay with detachment of at least three electrons, leading to charge reversal of the anionic precursor and the formation of positively charged photofragment ions. The same process is observed in heavy ion (12 MeV C4+) collisions with [dTGGGGT–2H]2− where inner shell vacancies are generated as well, but with smaller probability. Auger decay of a single K-vacancy in DNA, followed by detachment of three or more low energy electrons instead of a single high energy electron has profound implications for DNA damage and damage modelling. The production of three low kinetic energy electrons with short mean free path instead of one high kinetic energy electron with long mean free path implies that electron-induced DNA damage will be much more localized around the initial K-shell vacancy. The fragmentation channels, triggered by triple electron detachment Auger decay are predominantly related to protonated guanine base loss and even loss of protonated guanine dimers is tentatively observed. The fragmentation is not a consequence of the initial K-shell vacancy but purely due to multiple detachment of valence electrons, as a very similar positive ion fragmentation pattern is observed in femtosecond laser-induced dissociation experiments. A K-shell vacancy in DNA that is induced by a (therapeutically relevant) soft X-ray of MeV carbon ion, decays by Auger processes accompanied by emission of at least 3 low energy electrons.![]()
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Affiliation(s)
- Wen Li
- University of Groningen, Zernike Institute for Advanced Materials Nijenborgh 4 9747AG Groningen Netherlands
| | - Oksana Kavatsyuk
- University College Groningen Hoendiep 23/24 9718BG Groningen Netherlands
| | - Wessel Douma
- University of Groningen, Zernike Institute for Advanced Materials Nijenborgh 4 9747AG Groningen Netherlands
| | - Xin Wang
- University of Groningen, Zernike Institute for Advanced Materials Nijenborgh 4 9747AG Groningen Netherlands
| | - Ronnie Hoekstra
- University of Groningen, Zernike Institute for Advanced Materials Nijenborgh 4 9747AG Groningen Netherlands
| | - Dennis Mayer
- Universität Potsdam, Institut für Physik und Astronomie 14476 Potsdam Germany
| | - Matthew S Robinson
- Universität Potsdam, Institut für Physik und Astronomie 14476 Potsdam Germany.,Centre for Free Electron Lasers (CFEL), DESY Notkestraße 85 22607 Hamburg Germany
| | - Markus Gühr
- Universität Potsdam, Institut für Physik und Astronomie 14476 Potsdam Germany
| | - Mathieu Lalande
- CIMAP UMR 6252 (CEA/CNRS/ENSICAEN/Université de Caen Normandie) Boulevard Becquerel 14070 Caen Cedex 5 France
| | - Marwa Abdelmouleh
- CIMAP UMR 6252 (CEA/CNRS/ENSICAEN/Université de Caen Normandie) Boulevard Becquerel 14070 Caen Cedex 5 France
| | - Michal Ryszka
- CIMAP UMR 6252 (CEA/CNRS/ENSICAEN/Université de Caen Normandie) Boulevard Becquerel 14070 Caen Cedex 5 France
| | - Jean Christophe Poully
- CIMAP UMR 6252 (CEA/CNRS/ENSICAEN/Université de Caen Normandie) Boulevard Becquerel 14070 Caen Cedex 5 France
| | - Thomas Schlathölter
- University of Groningen, Zernike Institute for Advanced Materials Nijenborgh 4 9747AG Groningen Netherlands
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Pirovano G, Wilson TC, Reiner T. Auger: The future of precision medicine. Nucl Med Biol 2021; 96-97:50-53. [PMID: 33831745 PMCID: PMC8164972 DOI: 10.1016/j.nucmedbio.2021.03.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 03/09/2021] [Accepted: 03/09/2021] [Indexed: 12/11/2022]
Abstract
First reported by Lise Meitner in 1922 and independently by Pierre Auger in 1923, the Auger effect has been explored as a potential source for targeted radiotherapy. The Auger effect is based on the emission of a low energy electron (typically <25 keV) from an atom post electron capture (EC), internal conversion (IC), or incident X-rays excitation. This phenomenon can cause the emission of a primary electron and multiple electron tracks typically in the nearest proximity of the emission site (2-500 nm). The short range of the emitted Auger cascade results in medium/high levels of linear energy transfer (4-26 keV/μm) exerted on the surrounding tissue. This property makes Auger emitters the ideal candidates for delivering high levels of targeted radiation to a specific target with dimensions comparable to, for example, the DNA. By using a targeting vector such as a small molecule, peptide or antibody, one has the potential of delivering high levels of radiation to tumor specific biomarkers while circumventing off-site toxicity in healthy cells; a challenge which is harder to overcome when using other, longer range sources of radiation such as beta and alpha emitting radionuclides. Several reviews on Auger emitters have been published over the years with two recent examples. For these reviews and others, we support their analysis and therefore to avoid simple repetition, this commentary will seek to address additional aspects and viewpoints. Specifically, we will focus on those most promising preclinical and clinical studies using small molecules, peptides, antibodies and how these studies may serve as a template for future studies.
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Affiliation(s)
- Giacomo Pirovano
- Department of Radiology, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065, USA
| | - Thomas C Wilson
- Department of Radiology, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065, USA
| | - Thomas Reiner
- Department of Radiology, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065, USA; Department of Radiology, Weill Cornell Medical College, New York, NY 10065, USA; Chemical Biology Program, Memorial Sloan Kettering Cancer Center, New York City, NY 10065, USA.
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Domogauer JD, de Toledo SM, Howell RW, Azzam EI. Acquired radioresistance in cancer associated fibroblasts is concomitant with enhanced antioxidant potential and DNA repair capacity. Cell Commun Signal 2021; 19:30. [PMID: 33637118 PMCID: PMC7912493 DOI: 10.1186/s12964-021-00711-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Accepted: 01/18/2021] [Indexed: 12/21/2022] Open
Abstract
Background Cancer-associated fibroblasts (CAFs) are a major component of the cancer stroma, and their response to therapeutic treatments likely impacts the outcome. We tested the hypothesis that CAFs develop unique characteristics that enhance their resistance to ionizing radiation. Methods CAFs were generated through intimate coculture of normal human fibroblasts of skin or lung origin with various human cancer cell types using permeable microporous membrane inserts. Fibroblasts and cancer cells are grown intimately, yet separately, on either side of the insert’s membrane for extended times to generate activated fibroblast populations highly enriched in CAFs. Results The generated CAFs exhibited a decrease in Caveolin-1 protein expression levels, a CAF biomarker, which was further enhanced when the coculture was maintained under in-vivo-like oxygen tension conditions. The level of p21Waf1 was also attenuated, a characteristic also associated with accelerated tumor growth. Furthermore, the generated CAFs experienced perturbations in their redox environment as demonstrated by increases in protein carbonylation, mitochondrial superoxide anion levels, and modulation of the activity of the antioxidants, manganese superoxide dismutase and catalase. Propagation of the isolated CAFs for 25 population doublings was associated with enhanced genomic instability and a decrease in expression of the senescence markers β-galactosidase and p16INK4a. With relevance to radiotherapeutic treatments, CAFs in coculture with cancer cells of diverse origins (breast, brain, lung, and prostate) were resistant to the clastogenic effects of 137Cs γ rays compared to naïve fibroblasts. Addition of repair inhibitors of single- or double-stranded DNA breaks attenuated the resistance of CAFs to the clastogenic effects of γ rays, supporting a role for increased ability to repair DNA damage in CAF radioresistance. Conclusions This study reveals that CAFs are radioresistant and experience significant changes in indices of oxidative metabolism. The CAFs that survive radiation treatment likely modulate the fate of the associated cancer cells. Identifying them together with their mode of communication with cancer cells, and eradicating them, particularly when they may exist at the margin of the radiotherapy planning target volume, may improve the efficacy of cancer treatments.![]() Video Abstract
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Affiliation(s)
- Jason D Domogauer
- Division of Radiation Research and Center for Cell Signaling, Department of Radiology, Rutgers Biomedical and Health Sciences, New Jersey Medical School, Rutgers University, 205 South Orange Avenue, Room - F1212, Newark, NJ, USA
| | - Sonia M de Toledo
- Division of Radiation Research and Center for Cell Signaling, Department of Radiology, Rutgers Biomedical and Health Sciences, New Jersey Medical School, Rutgers University, 205 South Orange Avenue, Room - F1212, Newark, NJ, USA
| | - Roger W Howell
- Division of Radiation Research and Center for Cell Signaling, Department of Radiology, Rutgers Biomedical and Health Sciences, New Jersey Medical School, Rutgers University, 205 South Orange Avenue, Room - F1212, Newark, NJ, USA
| | - Edouard I Azzam
- Division of Radiation Research and Center for Cell Signaling, Department of Radiology, Rutgers Biomedical and Health Sciences, New Jersey Medical School, Rutgers University, 205 South Orange Avenue, Room - F1212, Newark, NJ, USA.
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