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Song H, Sgouros G. Alpha and Beta Radiation for Theragnostics. PET Clin 2024:S1556-8598(24)00021-X. [PMID: 38688775 DOI: 10.1016/j.cpet.2024.03.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/02/2024]
Abstract
Targeted radionuclide therapy (TRT) has significantly evolved from its beginnings with iodine-131 to employing carrier molecules with beta emitting isotopes like lutetium-177. With the success of Lu-177-DOTATATE for neuroendocrine tumors and Lu-177-PSMA-617 for prostate cancer, several other beta emitting radioisotopes, such as Cu-67 and Tb-161, are being explored for TRT. The field has also expanded into targeted alpha therapy (TAT) with agents like radium-223 for bone metastases in prostate cancer, and several other alpha emitter radioisotopes with carrier molecules, such as Ac-225, and Pb-212 under clinical trials. Despite these advancements, the scope of TRT in treating diverse solid tumors and integration with other therapies like immunotherapy remains under investigation. The success of antibody-drug conjugates further complements treatments with TRT, though challenges in treatment optimization continue.
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Affiliation(s)
- Hong Song
- Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, Stanford University, Stanford, CA 94305, USA.
| | - George Sgouros
- Division of Radiological Physics, Department of Radiology and Radiological Sciences, The Johns Hopkins University, Baltimore, MD 21205, USA
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2
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Abstract
Background Lead-212 (212Pb) is a promising radionuclide for targeted therapy, as it decays to α-particle emitter bismuth-212 (212Bi) via β-particle emission. This extends the problematic short half-life of 212Bi. In preparation for upcoming clinical trials with 212Pb, the feasibility of quantitative single photon-emission computed tomography/computed tomography (SPECT/CT) imaging of 212Pb was studied, with the purpose to explore the possibility of individualised patient dosimetric estimation. Results Both acquisition parameters (combining two different energy windows and two different collimators) and iterative reconstruction parameters (varying the iterations x subsets between 10 × 1, 15 × 1, 30 × 1, 30 × 2, 30 × 3, 30 × 4, and 30 × 30) were investigated to evaluate visual quality and quantitative uncertainties based on phantom images. Calibration factors were determined using a homogeneous phantom and were stable when the total activity imaged exceeded 1 MBq for all the imaging protocols studied, but they increased sharply as the activity decayed below 1 MBq. Both a 20% window centred on 239 keV and a 40% window on 79 keV, with dual scatter windows of 5% and 20%, respectively, could be used. Visual quality at the lowest activity concentrations was improved with the High Energy collimator and the 79 keV energy window. Fractional uncertainty in the activity quantitation, including uncertainties from calibration factors and small volume effects, in spheres of 2.6 ml in the NEMA phantom was 16–21% for all protocols with the 30 × 4 filtered reconstruction except the High Energy collimator with the 239 keV energy window. Quantitative analysis was possible both with and without filters, but the visual quality of the images improved with a filter. Conclusions Only minor differences were observed between the imaging protocols which were all determined suitable for quantitative imaging of 212Pb. As uncertainties generally decreased with increasing iterative updates in the reconstruction and recovery curves did not converge with few iterations, a high number of reconstruction updates are recommended for quantitative imaging. Supplementary Information The online version contains supplementary material available at 10.1186/s40658-022-00481-z.
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Affiliation(s)
- Monika Kvassheim
- Department of Physics and Computational Radiology, Division of Radiology and Nuclear Medicine, Oslo University Hospital, Oslo, Norway. .,Faculty of Medicine, University of Oslo, Oslo, Norway.
| | - Mona-Elisabeth R Revheim
- Faculty of Medicine, University of Oslo, Oslo, Norway.,Department of Nuclear Medicine, Division of Radiology and Nuclear Medicine, Oslo University Hospital, Oslo, Norway
| | - Caroline Stokke
- Department of Physics and Computational Radiology, Division of Radiology and Nuclear Medicine, Oslo University Hospital, Oslo, Norway.,Department of Physics, University of Oslo, Oslo, Norway
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Liatsou I, Yu J, Bastiaannet R, Li Z, Hobbs RF, Torgue J, Sgouros G. 212Pb-conjugated anti-rat HER2/ neu antibody against a neu-N derived murine mammary carcinoma cell line: cell kill and RBE in vitro. Int J Radiat Biol 2022; 98:1452-1461. [PMID: 35073214 PMCID: PMC9673603 DOI: 10.1080/09553002.2022.2033341] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
PURPOSE In the current work, the RBE of a 212Pb-conjugated anti-HER2/neu antibody construct has been evaluated, in vitro, by colony formation assay. The RBE was estimated by comparing two absorbed dose-survival curves: the first obtained from the conjugated 212Pb experiments (test radiation), the second obtained by parallel experiments of single bolus irradiation of external beam (reference radiation). MATERIALS AND METHODS Mammary carcinoma NT2.5 cells were treated with (0-3.70) kBq/ml of radiolabeled antibody. Nonspecific binding was assessed with addition of excess amount of unlabeled antibody. The colony formation curves were converted from activity concentration to cell nucleus absorbed dose by simulating the decay and transport of all daughter and secondary particles of 212Pb, using the Monte Carlo code GEANT 4. RESULTS The radiolabeled antibody yielded an RBE of 8.3 at 37% survival and a survival independent RBE (i.e. RBE2) of 9.9. Unbound/untargeted 212Pb-labeled antibody, as obtained in blocking experiments yielded minimal alpha-particle radiation to cells. Conclusions: These results further highlight the importance of specific targeting toward achieving tumor cell kill and low toxicity to normal tissue.
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Affiliation(s)
- Ioanna Liatsou
- Department of Radiology and Radiological Science, School of Medicine, Johns Hopkins University, Baltimore, USA
| | - Jing Yu
- Department of Radiology and Radiological Science, School of Medicine, Johns Hopkins University, Baltimore, USA
| | - Remco Bastiaannet
- Department of Radiology and Radiological Science, School of Medicine, Johns Hopkins University, Baltimore, USA
| | - Zhi Li
- Department of Radiology and Radiological Science, School of Medicine, Johns Hopkins University, Baltimore, USA
| | - Robert F. Hobbs
- Department of Radiation Oncology, School of Medicine, Johns Hopkins University, Baltimore, USA
| | | | - George Sgouros
- Department of Radiology and Radiological Science, School of Medicine, Johns Hopkins University, Baltimore, USA
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Byun BH, Kim MH, Han YH, Jeong HJ. KSNM60 in Non-thyroidal Radionuclide Therapy: Leaping into the Future. Nucl Med Mol Imaging 2021; 55:203-209. [PMID: 34721713 DOI: 10.1007/s13139-021-00703-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 05/02/2021] [Accepted: 05/31/2021] [Indexed: 11/28/2022] Open
Abstract
This year, the Korean Society of Nuclear Medicine (KSNM) is celebrating its 60th anniversary. Treatment, as well as diagnosis, has played a very important role in the development of nuclear medicine. Since I-131 was used for thyroid therapy in 1959, other radionuclide therapy is still being used, and attempts to use new radionuclide are increasing. In this review, we briefly summarize and introduce the therapies such as radioimmunotherapy, transarterial radioembolization, radionuclide therapy for neuroendocrine tumors, peptide receptor radionuclide therapy, control of metastatic bone pain, radiation synovectomy, radionuclide brachytherapy, alpha particle therapy, and boron neutron capture therapy, which has been being attempted so far in the field of nuclear medicine.
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Affiliation(s)
- Byung Hyun Byun
- Department of Nuclear Medicine, Korea Cancer Center Hospital, Korea Institute of Radiological and Medical Sciences (KIRAMS), Seoul, South Korea
| | - Myoung Hyoun Kim
- Department of Nuclear Medicine, Institute of Wonkwang Medical Science, Wonkwang University School of Medicine, Iksan, Jeollabuk-do South Korea
| | - Yeon-Hee Han
- Department of Nuclear Medicine, Research Institute of Clinical Medicine of Jeonbuk National University and Biomedical Research Institute of Jeonbuk National University Hospital, 20, Geonji-ro, Duckjin-gu, Jeonju-si, Jeollabuk-do 561-803 South Korea
| | - Hwan-Jeong Jeong
- Department of Nuclear Medicine, Research Institute of Clinical Medicine of Jeonbuk National University and Biomedical Research Institute of Jeonbuk National University Hospital, 20, Geonji-ro, Duckjin-gu, Jeonju-si, Jeollabuk-do 561-803 South Korea
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5
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Usta M. Continuous slowing-down approximation ranges of biological materials for 0.05-10 MeV alpha particles by using different approach methods. Appl Radiat Isot 2021; 178:109951. [PMID: 34537564 DOI: 10.1016/j.apradiso.2021.109951] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2020] [Revised: 09/07/2021] [Accepted: 09/13/2021] [Indexed: 10/20/2022]
Abstract
The goal of this study was to calculate the range values of alpha particles in bone, MS20 tissue substitute, and muscle targets using different approach methods. The range values were calculated using Gauss quadrature, Simpson 1/3, and trapezoidal numerical integration methods in continuous slowing-down approximation (CSDA). Overall, the Gauss quadrature method gave the best CSDA range values for the target materials. These results will be conducive to studies involving the interaction of radiation with biological materials.
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Affiliation(s)
- Metin Usta
- Department of Physics, Faculty of Arts and Sciences, Mustafa Kemal University, 31034, Hatay, Turkey.
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6
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Becker EM, Myjak MJ, Prinke AM, Kernan WJ, Homann SG. Evaluation of an airborne alpha and beta particle detection capability using an environmental continuous air monitor system. J Environ Radioact 2021; 228:106527. [PMID: 33421905 DOI: 10.1016/j.jenvrad.2020.106527] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2020] [Revised: 12/14/2020] [Accepted: 12/19/2020] [Indexed: 06/12/2023]
Abstract
We evaluate the ability of the Canberra Alpha Beta Environmental Continuous Air Monitor (ECAM) to detect and quantify airborne radiological contamination. The ECAM essentially consists of a passively-implanted planar silicon (PIPS) detector near a particulate filter through which outside air is pulled. Three years' worth of background measurements on three different systems were assessed and calibrated to compensate for changing conditions and develop an average background response for the systems. The ECAM was also exposed to several radionuclides of interest, including 235U and 239Pu, to measure the response to alpha and beta particle sources. Both standard calibration sources and custom sources consisting of aqueous radioisotope solutions absorbed into clean filters. The ECAM responses to these sources were then scaled to quantities of interest and injected on the averaged background. Various alarm algorithms were evaluated on the source-injected spectra for minimum detectable air concentration for a given false alarm rate. Even in the worst case, the ECAM was able to detect radionuclides of interest at 10% of the Derived Response Level (DRL) for each isotope based on early-phase Protective Action Guides (PAG). Quantification of the radionuclides was also evaluated for the various algorithms, with mixed results, but overall clearly indicating the optimal algorithms for alpha and beta particle alarm and quantification. Finally, a limited evaluation of the beta particle detection efficiency points to a detection energy threshold of approximately 290 keV.
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Affiliation(s)
- Eric M Becker
- Pacific Northwest National Laboratory, Richland, USA.
| | | | - Amanda M Prinke
- US Department of Homeland Security, Countering Weapons of Mass Destruction Office, Washington D.C, USA
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Özpolat ÖF, Alım B, Şakar E, Büyükyıldız M, Kurudirek M. Phy-X/ZeXTRa: a software for robust calculation of effective atomic numbers for photon, electron, proton, alpha particle, and carbon ion interactions. Radiat Environ Biophys 2020; 59:321-329. [PMID: 31960126 DOI: 10.1007/s00411-019-00829-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Accepted: 12/31/2019] [Indexed: 06/10/2023]
Abstract
The purpose of the present work is robust calculation of effective atomic numbers ([Formula: see text]s) for photon, electron, proton, alpha particle and carbon ion interactions through the newly developed software, Phy-X/ZeXTRa (Zeff of materials for X-Type Radiation attenuation). A pool of total mass attenuation and energy absorption coefficients (for photons) and total mass stopping powers (for charged particles) for elements was constructed first. Then, a matrix of interaction cross sections for elements Z = 1-92 was constructed. Finally, effective atomic numbers were calculated for any material by interpolating adjacent cross sections through a linear logarithmic interpolation formula. The results for [Formula: see text] for photon interaction were compared with those calculated through Mayneord's formula, which suggests a single-valued [Formula: see text] for any material for low-energy photons for which photoelectric absorption is the dominant interaction process. The single-valued [Formula: see text] was found to agree well with that obtained by other methods, in the low-energy region. In addition, [Formula: see text] values of various materials of biological interest were compared with those obtained experimentally at 59.54 keV. In general, the agreement between values calculated with Phy-X/ZeXTRa and Auto-Zeff and those measured were satisfactory. A comparison of [Formula: see text] values for photon energy absorption calculated with Phy-X/ZeXTRa and literature values for a nucleotide base, adenine, was made, and the relative difference (RD) in [Formula: see text] between Phy-X/ZeXTRa and literature values was found to be 2% < RD < 11%, at low photon energies (1-100 keV), while it was less than 1% at energies higher than 100 keV. Highest [Formula: see text] values were observed at low photon energies, where photoelectric absorption dominates photon interaction. For electrons, corresponding RD(%) values in [Formula: see text] were found to be in the range 0.4 ≤ RD(%) ≤ 1.7, while for heavy charged particle interactions it was 2.4 ≤ RD(%) ≤ 4.2 for total proton interaction and 0 ≤ RD(%) ≤ 8 for total alpha particle interaction. In view of the importance of [Formula: see text] for identifying and differentiating tissues in diagnostic imaging as well as for estimating accurate dose in radiotherapy and particle-beam therapy, Phy-X/ZeXTRa could be used for fast and accurate calculation of [Formula: see text] in a wide energy range for both photon and charged particle (electrons, protons, alpha particles and C ions) interactions.
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Affiliation(s)
- Ö F Özpolat
- Department of Physics, Faculty of Science, Atatürk University, 25240, Erzurum, Turkey
| | - B Alım
- Department of Electricity and Energy, Technical Scientific Vocational School, Bayburt University, 69000, Bayburt, Turkey
| | - E Şakar
- Department of Physics, Faculty of Science, Atatürk University, 25240, Erzurum, Turkey
| | - M Büyükyıldız
- Termal Vocational School, Yalova University, 77400, Yalova, Turkey
| | - M Kurudirek
- Department of Physics, Faculty of Science, Atatürk University, 25240, Erzurum, Turkey.
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Bedenko SV, Ghal-Eh N, Lutsik IO, Shamanin IV. A fuel for generation IV nuclear energy system: Isotopic composition and radiation characteristics. Appl Radiat Isot 2019; 147:189-196. [PMID: 30884287 DOI: 10.1016/j.apradiso.2019.03.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Revised: 02/28/2019] [Accepted: 03/01/2019] [Indexed: 11/26/2022]
Abstract
This paper reports on an important issue of designing appropriate nuclear fuel of a high-temperature gas-cooled nuclear reactor operating in a thorium-plutonium nuclear fuel cycle. The neutronic calculations for a fuel of specific isotopic composition were performed before the analyses were done on the alpha emission probabilities, and on the neutron and photon sources as a result of (α,n) reaction. The main focus was on the quantitative evaluation of the neutron yield and the neutron energy spectrum for the generated neutrons through (α,n) reaction on light nuclei of dispersed nuclear fuel. Tests were carried out with the aim of creating an efficient calculation tool for the initial evaluation of the radiation characteristics for the irradiated multilayer nuclear fuel with different configurations and compositions.
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Affiliation(s)
- S V Bedenko
- National Research Tomsk Polytechnic University, Tomsk, Russian Federation.
| | - N Ghal-Eh
- School of Physics, Damghan University, Damghan, Iran; Department of Physics, School of Sciences, Ferdowsi University of Mashhad, Mashhad, Iran
| | - I O Lutsik
- National Research Tomsk Polytechnic University, Tomsk, Russian Federation
| | - I V Shamanin
- National Research Tomsk Polytechnic University, Tomsk, Russian Federation
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Abstract
INTRODUCTION Metastatic prostate cancer continues to be a leading cause of morbidity and mortality in men with prostate cancer. Over the last decade, the treatment landscape for patients with castrate-resistant disease has drastically changed, with several novel agents demonstrating an improvement in overall survival in large, multi-institutional randomized trials. Traditional treatment with radioisotopes has largely been in the palliative setting. However, the first in class radiopharmaceutical radium-223 has emerged as the only bone-directed treatment option demonstrating an improvement in overall survival. METHODS Medline publications from 1990 to 2016 were searched and reviewed to assess the use of currently approved radioisotopes in the management of prostate cancer including emerging data regarding integration with novel systemic therapies. New positron emission tomography-based radiotracers for advanced molecular imaging of prostate cancer were also queried. RESULTS Radioisotopes play a crucial role in the diagnosis and treatment of prostate cancer in the definitive and metastatic setting. Molecular imaging of prostate cancer and theranostics are currently being investigated in the clinical arena. CONCLUSIONS The use of modern radioisotopes in selected patients with mCRPC is associated with improvements in overall survival, pain control, and quality of life.
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Affiliation(s)
- Amar Raval
- Department of Urology, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, USA
| | - Tu D. Dan
- Department of Radiation Oncology, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, USA
| | - Noelle L. Williams
- Department of Radiation Oncology, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, USA
| | - Andrew Pridjian
- Department of Urology, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, USA
| | - Robert B. Den
- Department of Radiation Oncology, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, USA
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Takalkar A, Adams S, Subbiah V. Radium-223 dichloride bone-targeted alpha particle therapy for hormone-refractory breast cancer metastatic to bone. Exp Hematol Oncol 2014; 3:23. [PMID: 25243101 PMCID: PMC4168986 DOI: 10.1186/2162-3619-3-23] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2014] [Accepted: 08/18/2014] [Indexed: 02/08/2023] Open
Abstract
Background Hormone-refractory breast cancer metastatic to bone is a clinically challenging disease associated with high morbidity, poor prognosis, and impaired quality of life owing to pain and skeletal-related events. In a preclinical study using a mouse model of breast cancer and bone metastases, Ra-223 dichloride was incorporated into bone matrix and inhibited proliferation of breast cancer cells and differentiation of osteoblasts and osteoclasts (all P values < .001) in vitro. Ra-223 dichloride also induced double-strand DNA breaks in cancer cells in vivo. Methods The US Food and Drug Administration recently approved radium-223 (Ra-223) dichloride (Ra-223; Xofigo injection) alpha-particle therapy for the treatment of symptomatic bone metastases in patients with castration-resistant prostate cancer. On the basis of a strong preclinical rationale, we used Ra-223 dichloride to treat bone metastases in a patient with breast cancer. Results A 44-year-old white woman with metastatic breast cancer who was estrogen receptor–positive, BRCA1-negative, BRCA2-negative, PIK3CA mutation (p.His1047Arg) positive presented with diffuse bony metastases and bone pain. She had hormone refractory and chemotherapy refractory breast cancer. After Ra-223 therapy initiation her bone pain improved, with corresponding decrease in tumor markers and mixed response in 18F-FDG PET/CT and 18F-NaF bone PET/CT. The patient derived clinical benefit from therapy. Conclusion We have shown that Ra-223 dichloride can be safely administered in a patient with hormone-refractory bone metastasis from breast cancer at the US FDA–approved dose for prostate cancer. Furthermore, because the treatment did not cause any drop in hematologic parameters, it has the potential to be combined with other radiosensitizing therapies, which may include chemotherapy or targeted therapies. Given that Ra-223 dichloride is already commercially available, this case report may help future patients and provide a rationale for initiating clinical research in the use of Ra-223 dichloride to treat bone metastasis from breast cancer. A randomized clinical trial is needed to provide evidence of efficacy, safety, and good outcomes.
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Affiliation(s)
- Amol Takalkar
- PET Imaging Center, Biomedical Research Foundation of Northwest Louisiana, Shreveport, LA 71103, USA
| | - Scott Adams
- PET Imaging Center, Biomedical Research Foundation of Northwest Louisiana, Shreveport, LA 71103, USA
| | - Vivek Subbiah
- Department of Investigational Cancer Therapeutics (Phase I Clinical Trials Program), Division of Cancer Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
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Lyckesvärd MN, Delle U, Kahu H, Lindegren S, Jensen H, Bäck T, Swanpalmer J, Elmroth K. Alpha particle induced DNA damage and repair in normal cultured thyrocytes of different proliferation status. Mutat Res 2014; 765:48-56. [PMID: 24769180 DOI: 10.1016/j.mrfmmm.2014.04.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2013] [Revised: 04/01/2014] [Accepted: 04/10/2014] [Indexed: 10/25/2022]
Abstract
Childhood exposure to ionizing radiation increases the risk of developing thyroid cancer later in life and this is suggested to be due to higher proliferation of the young thyroid. The interest of using high-LET alpha particles from Astatine-211 ((211)At), concentrated in the thyroid by the same mechanism as (131)I [1], in cancer treatment has increased during recent years because of its high efficiency in inducing biological damage and beneficial dose distribution when compared to low-LET radiation. Most knowledge of the DNA damage response in thyroid is from studies using low-LET irradiation and much less is known of high-LET irradiation. In this paper we investigated the DNA damage response and biological consequences to photons from Cobolt-60 ((60)Co) and alpha particles from (211)At in normal primary thyrocytes of different cell cycle status. For both radiation qualities the intensity levels of γH2AX decreased during the first 24h in both cycling and stationary cultures and complete repair was seen in all cultures but cycling cells exposed to (211)At. Compared to stationary cells alpha particles were more harmful for cycling cultures, an effect also seen at the pChk2 levels. Increasing ratios of micronuclei per cell nuclei were seen up to 1Gy (211)At. We found that primary thyrocytes were much more sensitive to alpha particle exposure compared with low-LET photons. Calculations of the relative biological effectiveness yielded higher RBE for cycling cells compared with stationary cultures at a modest level of damage, clearly demonstrating that cell cycle status influences the relative effectiveness of alpha particles.
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Affiliation(s)
| | - Ulla Delle
- Department of Oncology, Sahlgrenska Academy, University of Gothenburg, Sweden
| | - Helena Kahu
- Department of Oncology, Sahlgrenska Academy, University of Gothenburg, Sweden
| | - Sture Lindegren
- Department of Radiation Physics, Sahlgrenska Academy, University of Gothenburg, Sweden
| | - Holger Jensen
- The PET and Cyclotron Unit Copenhagen University Hospital, Rigshospitalet, Denmark
| | - Tom Bäck
- Department of Radiation Physics, Sahlgrenska Academy, University of Gothenburg, Sweden
| | - John Swanpalmer
- Department of Medical Physics and Biomedical Engineering, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Kecke Elmroth
- Department of Oncology, Sahlgrenska Academy, University of Gothenburg, Sweden
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