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Caravaca J, Bobba KN, Du S, Peter R, Gullberg GT, Bidkar AP, Flavell RR, Seo Y. A Technique to Quantify Very Low Activities in Regions of Interest With a Collimatorless Detector. IEEE TRANSACTIONS ON MEDICAL IMAGING 2024; 43:2745-2757. [PMID: 38478457 PMCID: PMC11293990 DOI: 10.1109/tmi.2024.3377142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/20/2024]
Abstract
We present a new method to measure sub-microcurie activities of photon-emitting radionuclides in organs and lesions of small animals in vivo. Our technique, named the collimator-less likelihood fit, combines a very high sensitivity collimatorless detector with a Monte Carlo-based likelihood fit in order to estimate the activities in previously segmented regions of interest along with their uncertainties. This is done directly from the photon projections in our collimatorless detector and from the region of interest segmentation provided by an x-ray computed tomography scan. We have extensively validated our approach with 225Ac experimentally in spherical phantoms and mouse phantoms, and also numerically with simulations of a realistic mouse anatomy. Our method yields statistically unbiased results with uncertainties smaller than 20% for activities as low as ~111Bq (3nCi) and for exposures under 30 minutes. We demonstrate that our method yields more robust recovery coefficients when compared to SPECT imaging with a commercial pre-clinical scanner, specially at very low activities. Thus, our technique is complementary to traditional SPECT/CT imaging since it provides a more accurate and precise organ and tumor dosimetry, with a more limited spatial information. Finally, our technique is specially significant in extremely low-activity scenarios when SPECT/CT imaging is simply not viable.
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Das SK, Ali M, Shetake NG, Pandey BN, Kumar A. Thorium Alters Lung Surfactant Protein Expression in Alveolar Epithelial Cells: In Vitro and In Vivo Investigation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:12330-12342. [PMID: 38772857 DOI: 10.1021/acs.est.4c00254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2024]
Abstract
Thorium-232 (Th), the most abundant naturally occurring nuclear fuel, has been identified as a sustainable source of energy. In view of its large-scale utilization and human evidence of lung disorders and carcinogenicity, it is imperative to understand the effect of Th exposure on lung cells. The present study investigated the effect of Th-dioxide (1-100 μg/mL, 24-48 h) on expression of surfactant proteins (SPs) (SP-A, SP-B, SP-C, and SP-D, which are essential to maintain lung's surface tension and host-defense) in human lung cells (WI26 and A549), representative of alveolar cell type-I and type-II, respectively. Results demonstrated the inhibitory effect of Th on transcriptional expression of SP-A, SP-B, and SP-C. However, Th promoted the mRNA expression of SP-D in A549 and reduced its expression in WI26. To a significant extent, the effect of Th on SPs was found to be in accordance with their protein levels. Moreover, Th exposure altered the extracellular release of SP-D/A from A549, which remained unaltered in WI26. Our results suggested the differential role of oxidative stress and ATM and HSP90 signaling in Th-induced alterations of SPs. These effects of Th were found to be consistent in lung tissues of mice exposed to Th aerosols, suggesting a potential role of SPs in Th-associated lung disorders.
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Affiliation(s)
- Sourav Kumar Das
- Radiation Biology & Health Sciences Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085, India
- Homi Bhabha National Institute, Anushaktinagar, Mumbai 400 094, India
| | - Manjoor Ali
- Radiation Biology & Health Sciences Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085, India
| | - Neena Girish Shetake
- Radiation Biology & Health Sciences Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085, India
- Homi Bhabha National Institute, Anushaktinagar, Mumbai 400 094, India
| | - Badri Narain Pandey
- Radiation Biology & Health Sciences Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085, India
- Homi Bhabha National Institute, Anushaktinagar, Mumbai 400 094, India
| | - Amit Kumar
- Radiation Biology & Health Sciences Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085, India
- Homi Bhabha National Institute, Anushaktinagar, Mumbai 400 094, India
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Kleynhans J, Ebenhan T, Cleeren F, Sathekge MM. Can current preclinical strategies for radiopharmaceutical development meet the needs of targeted alpha therapy? Eur J Nucl Med Mol Imaging 2024; 51:1965-1980. [PMID: 38676735 PMCID: PMC11139742 DOI: 10.1007/s00259-024-06719-5] [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: 02/22/2024] [Accepted: 04/15/2024] [Indexed: 04/29/2024]
Abstract
Preclinical studies are essential for effectively evaluating TAT radiopharmaceuticals. Given the current suboptimal supply chain of these radionuclides, animal studies must be refined to produce the most translatable TAT agents with the greatest clinical potential. Vector design is pivotal, emphasizing harmonious physical and biological characteristics among the vector, target, and radionuclide. The scarcity of alpha-emitting radionuclides remains a significant consideration. Actinium-225 and lead-212 appear as the most readily available radionuclides at this stage. Available animal models for researchers encompass xenografts, allografts, and PDX (patient-derived xenograft) models. Emerging strategies for imaging alpha-emitters are also briefly explored. Ultimately, preclinical research must address two critical aspects: (1) offering valuable insights into balancing safety and efficacy, and (2) providing guidance on the optimal dosing of the TAT agent.
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Affiliation(s)
- Janke Kleynhans
- Laboratory for Radiopharmaceutical Research, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Leuven, 3000, Belgium
| | - Thomas Ebenhan
- Department of Nuclear Medicine, University of Pretoria, and Steve Biko Academic Hospital, Pretoria, 0001, South Africa
- Department of Nuclear Medicine, Steve Biko Academic Hospital, Pretoria, 0001, South Africa
| | - Frederik Cleeren
- Laboratory for Radiopharmaceutical Research, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Leuven, 3000, Belgium
| | - Mike Machaba Sathekge
- Department of Nuclear Medicine, Steve Biko Academic Hospital, Pretoria, 0001, South Africa.
- Preclinical Imaging Facility, Nuclear Medicine Research Infrastructure, Pretoria, 0001, South Africa.
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Ramonaheng K, Qebetu M, Ndlovu H, Swanepoel C, Smith L, Mdanda S, Mdlophane A, Sathekge M. Activity quantification and dosimetry in radiopharmaceutical therapy with reference to 177Lutetium. FRONTIERS IN NUCLEAR MEDICINE (LAUSANNE, SWITZERLAND) 2024; 4:1355912. [PMID: 39355215 PMCID: PMC11440950 DOI: 10.3389/fnume.2024.1355912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Accepted: 03/12/2024] [Indexed: 10/03/2024]
Abstract
Radiopharmaceutical therapy has been widely adopted owing primarily to the development of novel radiopharmaceuticals. To fully utilize the potential of these RPTs in the era of precision medicine, therapy must be optimized to the patient's tumor characteristics. The vastly disparate dosimetry methodologies need to be harmonized as the first step towards this. Multiple factors play a crucial role in the shift from empirical activity administration to patient-specific dosimetry-based administrations from RPT. Factors such as variable responses seen in patients with presumably similar clinical characteristics underscore the need to standardize and validate dosimetry calculations. These efforts combined with ongoing initiatives to streamline the dosimetry process facilitate the implementation of radiomolecular precision oncology. However, various challenges hinder the widespread adoption of personalized dosimetry-based activity administration, particularly when compared to the more convenient and resource-efficient approach of empiric activity administration. This review outlines the fundamental principles, procedures, and methodologies related to image activity quantification and dosimetry with a specific focus on 177Lutetium-based radiopharmaceuticals.
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Affiliation(s)
- Keamogetswe Ramonaheng
- Department of Medical Physics and Radiobiology, Nuclear Medicine Research, Infrastructure (NuMeRI) NPC, Pretoria, South Africa
- Department of Nuclear Medicine, Steve Biko Academic Hospital, Pretoria, South Africa
- Department of Nuclear Medicine, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa
| | - Milani Qebetu
- Department of Medical Physics and Radiobiology, Nuclear Medicine Research, Infrastructure (NuMeRI) NPC, Pretoria, South Africa
- Department of Nuclear Medicine, Steve Biko Academic Hospital, Pretoria, South Africa
| | - Honest Ndlovu
- Department of Medical Physics and Radiobiology, Nuclear Medicine Research, Infrastructure (NuMeRI) NPC, Pretoria, South Africa
- Department of Nuclear Medicine, Steve Biko Academic Hospital, Pretoria, South Africa
- Department of Nuclear Medicine, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa
| | - Cecile Swanepoel
- Department of Medical Physics and Radiobiology, Nuclear Medicine Research, Infrastructure (NuMeRI) NPC, Pretoria, South Africa
- Department of Nuclear Medicine, Steve Biko Academic Hospital, Pretoria, South Africa
| | - Liani Smith
- Department of Medical Physics and Radiobiology, Nuclear Medicine Research, Infrastructure (NuMeRI) NPC, Pretoria, South Africa
- Department of Nuclear Medicine, Steve Biko Academic Hospital, Pretoria, South Africa
| | - Sipho Mdanda
- Department of Medical Physics and Radiobiology, Nuclear Medicine Research, Infrastructure (NuMeRI) NPC, Pretoria, South Africa
- Department of Nuclear Medicine, Steve Biko Academic Hospital, Pretoria, South Africa
- Department of Nuclear Medicine, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa
| | - Amanda Mdlophane
- Department of Medical Physics and Radiobiology, Nuclear Medicine Research, Infrastructure (NuMeRI) NPC, Pretoria, South Africa
- Department of Nuclear Medicine, Steve Biko Academic Hospital, Pretoria, South Africa
- Department of Nuclear Medicine, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa
| | - Mike Sathekge
- Department of Medical Physics and Radiobiology, Nuclear Medicine Research, Infrastructure (NuMeRI) NPC, Pretoria, South Africa
- Department of Nuclear Medicine, Steve Biko Academic Hospital, Pretoria, South Africa
- Department of Nuclear Medicine, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa
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Bowden G, Scott PJH, Boros E. Radiochemistry: A Hot Field with Opportunities for Cool Chemistry. ACS CENTRAL SCIENCE 2023; 9:2183-2195. [PMID: 38161375 PMCID: PMC10755734 DOI: 10.1021/acscentsci.3c01050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/19/2023] [Revised: 10/20/2023] [Accepted: 10/24/2023] [Indexed: 01/03/2024]
Abstract
Recent Food and Drug Administration (FDA) approval of diagnostic and therapeutic radiopharmaceuticals and concurrent miniaturization of particle accelerators leading to improved access has fueled interest in the development of chemical transformations suitable for short-lived radioactive isotopes on the tracer scale. This recent renaissance of radiochemistry is paired with new opportunities to study fundamental chemical behavior and reactivity of elements to improve their production, separation, and incorporation into bioactive molecules to generate new radiopharmaceuticals. This outlook outlines pertinent challenges in the field of radiochemistry and indicates areas of opportunity for chemical discovery and development, including those of clinically established (C-11, F-18) and experimental radionuclides in preclinical development across the periodic table.
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Affiliation(s)
- Gregory
D. Bowden
- Department
of Radiology, University of Michigan, 1301 Catherine, Ann Arbor, Michigan 48109, United States
- Werner
Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tuebingen, 72074 Tuebingen, Germany
- Cluster
of Excellence iFIT (EXC 2180) “Image Guided and Functionally
Instructed Tumor Therapies”, Eberhard
Karls University of Tuebingen, 72074 Tuebingen, Germany
| | - Peter J. H. Scott
- Department
of Radiology, University of Michigan, 1301 Catherine, Ann Arbor, Michigan 48109, United States
| | - Eszter Boros
- Department
of Chemistry, University of Wisconsin, 1101 University Avenue, Madison, Wisconsin 53706, United States
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Conte M, De Feo MS, Frantellizzi V, Marampon F, Filippi L, Schillaci O, De Vincentis G. Extraosseous distribution of 99mTc-diphosphonates during bone scintigraphy: review of the literature with case series presentation. Int J Radiat Biol 2023; 100:18-27. [PMID: 37561127 DOI: 10.1080/09553002.2023.2242935] [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: 08/12/2022] [Revised: 04/12/2023] [Accepted: 07/20/2023] [Indexed: 08/11/2023]
Abstract
PURPOSE Technetium-99m (99mTc)-diphosphonates represent the most common radiopharmaceutical used for bone scintigraphy. Even if the uptake in bone tissue has been widely explored, atypical uptake could be seen in soft tissue malignancies during bone scintigraphy. Increased vascularization and endothelium permeability represent front-row players in the biodistribution of the tracer, albeit other causes have been identified such as trauma, necrosis, the presence of calcification in metastasis, the pH of the tissue and consequently the type of ion concentration. CONCLUSION The aim of this paper is to summarize the state of art of atypical soft tissue uptake seen in cancer tissues. The research was conducted on PubMed. The analysis of the literature suggests that calcium metabolism and ionic saturation have a pivotal role in the biodistribution of bone tracers. This phenomenon ranks in a complex scenario that includes carcinogenesis and cancer environment aspects. We also report two cases in our Institution in which atypical uptake in cancer tissues was observed.
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Affiliation(s)
- Miriam Conte
- Department of Radiological Sciences, Oncology and Anatomo-Pathology, University of Rome, Sapienza, Rome, Italy
| | - Maria Silvia De Feo
- Department of Radiological Sciences, Oncology and Anatomo-Pathology, University of Rome, Sapienza, Rome, Italy
| | - Viviana Frantellizzi
- Department of Radiological Sciences, Oncology and Anatomo-Pathology, University of Rome, Sapienza, Rome, Italy
| | - Francesco Marampon
- Department of Radiological Sciences, Oncology and Anatomo-Pathology, University of Rome, Sapienza, Rome, Italy
| | - Luca Filippi
- Department of Nuclear Medicine, Santa Maria Goretti Hospital, Latina, Italy
| | - Orazio Schillaci
- Department of Biomedicine and Prevention, University Tor Vergata, Rome, Italy
| | - Giuseppe De Vincentis
- Department of Radiological Sciences, Oncology and Anatomo-Pathology, University of Rome, Sapienza, Rome, Italy
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Juzeniene A, Stenberg VY, Bruland ØS, Revheim ME, Larsen RH. Dual targeting with 224Ra/ 212Pb-conjugates for targeted alpha therapy of disseminated cancers: A conceptual approach. Front Med (Lausanne) 2023; 9:1051825. [PMID: 36733936 PMCID: PMC9887039 DOI: 10.3389/fmed.2022.1051825] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Accepted: 12/05/2022] [Indexed: 01/18/2023] Open
Abstract
Metastases are the primary cause of death among cancer patients and efficacious new treatments are sorely needed. Targeted alpha-emitting radiopharmaceuticals that are highly cytotoxic may fulfill this critical need. The focus of this paper is to describe and explore a novel technology that may improve the therapeutic effect of targeted alpha therapy by combining two radionuclides from the same decay chain in the same solution. We hypothesize that the dual targeting solution containing bone-seeking 224Ra and cell-directed complexes of progeny 212Pb is a promising approach to treat metastatic cancers with bone and soft tissue lesions as well as skeletal metastases of mixed lytic/osteoblastic nature. A novel liquid 224Ra/212Pb-generator for rapid preparation of a dual targeting solution is described. Cancer cell targeting monoclonal antibodies, their fragments, synthetic proteins or peptides can all be radiolabeled with 212Pb in the 224Ra-solution in transient equilibrium with daughter nuclides. Thus, 224Ra targets stromal elements in sclerotic bone metastases and 212Pb-chelated-conjugate targets tumor cells of metastatic prostate cancer or osteosarcoma. The dual targeting solution may also be explored to treat metastatic breast cancer or multiple myeloma after manipulation of bone metastases to a more osteoblastic phenotype by the use of bisphosphonates, denosumab, bortezomib or hormone therapy prior to treatment. This may improve targeting of bone-seeking 224Ra and render an augmented radiation dose deposited within metastases. Our preliminary preclinical studies provide conceptual evidence that the dual 224Ra-solution with bone or tumor-targeted delivery of 212Pb has potential to inhibit cancer metastases without significant toxicity. In some settings, the use of a booster dose of purified 212Pb-conjugate alone could be required to elevate the effect of this tumor cell directed component, if needed, e.g., in a fractionated treatment regimen, where the dual targeting solution will act as maintenance treatment.
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Affiliation(s)
- Asta Juzeniene
- Department of Radiation Biology, Institute for Cancer Research, The Norwegian Radium Hospital, Oslo University Hospital, Oslo, Norway
- Department of Physics, University of Oslo, Oslo, Norway
| | - Vilde Yuli Stenberg
- Department of Radiation Biology, Institute for Cancer Research, The Norwegian Radium Hospital, Oslo University Hospital, Oslo, Norway
- Institute for Clinical Medicine, University of Oslo, Oslo, Norway
- ARTBIO AS, Oslo, Norway
| | - Øyvind Sverre Bruland
- Institute for Clinical Medicine, University of Oslo, Oslo, Norway
- Department of Oncology, The Norwegian Radium Hospital, Oslo University Hospital, Oslo, Norway
| | - Mona-Elisabeth Revheim
- Institute for Clinical Medicine, University of Oslo, Oslo, Norway
- Division of Radiology and Nuclear Medicine, Oslo University Hospital, Oslo, Norway
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Kozempel J, Sakmár M, Janská T, Vlk M. Study of 213Bi and 211Pb Recoils Release from 223Ra Labelled TiO 2 Nanoparticles. MATERIALS (BASEL, SWITZERLAND) 2022; 16:343. [PMID: 36614682 PMCID: PMC9821810 DOI: 10.3390/ma16010343] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Revised: 12/22/2022] [Accepted: 12/26/2022] [Indexed: 06/17/2023]
Abstract
Nanoparticles of various materials were proposed as carriers of nuclides in targeted alpha particle therapy to at least partially eliminate the nuclear recoil effect causing the unwanted release of radioactive progeny originating in nuclear decay series of so-called in vivo generators. Here, we report on the study of 211Pb and 211Bi recoils release from the 223Ra surface-labelled TiO2 nanoparticles in the concentration range of 0.01-1 mg/mL using two phase separation methods different in their kinetics in order to test the ability of progeny resorption. We have found significant differences between the centrifugation and the dialysis used for labelled NPs separation as well as that the release of 211Pb and 211Bi from the nanoparticles also depends on the NPs dispersion concentration. These findings support our previously proposed recoils-retaining mechanism of the progeny by their resorption on the NPs surface. At the 24 h time-point, the highest overall released progeny fractions were observed using centrifugation (4.0% and 13.5% for 211Pb and 211Bi, respectively) at 0.01 mg/mL TiO2 concentration. The lowest overall released fractions at the 24 h time-point (1.5% and 2.5% for 211Pb and 211Bi respectively) were observed using dialysis at 1 mg/mL TiO2 concentration. Our findings also indicate that the in vitro stability tests of such radionuclide systems designed to retain recoil-progeny may end up with biased results and particular care needs to be given to in vitro stability test experimental setup to mimic in vivo dynamic conditions. On the other hand, controlled and well-defined progeny release may enhance the alpha-emitter radiation therapy of some tumours.
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Filippi L, Palumbo B, Frantellizzi V, Nuvoli S, De Vincentis G, Spanu A, Schillaci O. Prostate-specific membrane antigen-directed imaging and radioguided surgery with single-photon emission computed tomography: state of the art and future outlook. Expert Rev Med Devices 2022; 19:815-824. [PMID: 36370108 DOI: 10.1080/17434440.2022.2146999] [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: 11/13/2022]
Abstract
INTRODUCTION Prostate-specific membrane antigen (PSMA) has emerged as a highly relevant target for prostate cancer (PC) diagnosis and therapy. PSMA inhibitors targeting PSMA-enzymatic domain have been successfully labeled with radionuclides emitting positrons or gamma-photons, thus obtaining tracers suitable for imaging with positron emission computed tomography (PET/CT) or single-photon emission tomography (SPECT). AREAS COVERED The different approaches for obtaining PSMA-ligands labeled with gamma-emitting nuclides (99mTc or111In) are reviewed. Furthermore, the applications of 99mTc/111In-PSMA SPECT for the imaging of PC patients in different clinical settings (staging or biochemical recurrence) are covered. Lastly, the employment of PSMA-targeted SPECT tracers for radioguided surgery (RGS) during primary or salvage lymphadenectomy is discussed. EXPERT OPINION RGS provided satisfying preliminary results in both primary and salvage lymphadenectomy, allowing to discriminate between pathological and non-pathological nodes with high accuracy, although prospective studies with larger cohorts are needed to further validate this surgical approach. The potential of PSMA-targeted SPECT/CT has not been fully explored yet, but it might represent a relatively cost-effective alternative to PSMA PET/CT in limited resource environments. In this perspective, the implementation of novel SPECT technologies or algorithms, such as semiconductor-ionization detectors or resolution recovery reconstruction, will be topic of future investigation.
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Affiliation(s)
- Luca Filippi
- Department of Nuclear Medicine, Santa Maria Goretti Hospital, Latina, Italy
| | - Barbara Palumbo
- Section of Nuclear Medicine and Health Physics, Department of Medicine and Surgery, Università Degli Studi di Perugia, Piazza Lucio Severi 1, 06132 Perugia, Italy
| | - Viviana Frantellizzi
- Department of Radiological Sciences, Oncology and Anatomo-Pathology, Sapienza University of Rome, 00161 Rome, Italy
| | - Susanna Nuvoli
- Unit of Nuclear Medicine, Department of Medical, Surgical and Experimental Sciences, University of Sassari, 07100 Sassari, Italy
| | - Giuseppe De Vincentis
- Department of Radiological Sciences, Oncology and Anatomo-Pathology, Sapienza University of Rome, 00161 Rome, Italy
| | - Angela Spanu
- Unit of Nuclear Medicine, Department of Medical, Surgical and Experimental Sciences, University of Sassari, 07100 Sassari, Italy
| | - Orazio Schillaci
- Department of Biomedicine and Prevention, University Tor Vergata, Rome, Italy.,IRCCS Neuromed, Pozzilli, Italy
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Peter R, Sandmaier BM, Dion MP, Frost SHL, Santos EB, Kenoyer A, Hamlin DK, Wilbur DS, Stewart RD, Fisher DR, Vetter K, Seo Y, Miller BW. Small-scale (sub-organ and cellular level) alpha-particle dosimetry methods using an iQID digital autoradiography imaging system. Sci Rep 2022; 12:17934. [PMID: 36289434 PMCID: PMC9606121 DOI: 10.1038/s41598-022-22664-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Accepted: 10/18/2022] [Indexed: 01/20/2023] Open
Abstract
Targeted radiopharmaceutical therapy with alpha-particle emitters (αRPT) is advantageous in cancer treatment because the short range and high local energy deposition of alpha particles enable precise radiation delivery and efficient tumor cell killing. However, these properties create sub-organ dose deposition effects that are not easily characterized by direct gamma-ray imaging (PET or SPECT). We present a computational procedure to determine the spatial distribution of absorbed dose from alpha-emitting radionuclides in tissues using digital autoradiography activity images from an ionizing-radiation quantum imaging detector (iQID). Data from 211At-radioimmunotherapy studies for allogeneic hematopoietic cell transplantation in a canine model were used to develop these methods. Nine healthy canines were treated with 16.9-30.9 MBq 211At/mg monoclonal antibodies (mAb). Lymph node biopsies from early (2-5 h) and late (19-20 h) time points (16 total) were obtained, with 10-20 consecutive 12-µm cryosections extracted from each and imaged with an iQID device. iQID spatial activity images were registered within a 3D volume for dose-point-kernel convolution, producing dose-rate maps. The accumulated absorbed doses for high- and low-rate regions were 9 ± 4 Gy and 1.2 ± 0.8 Gy from separate dose-rate curves, respectively. We further assess uptake uniformity, co-registration with histological pathology, and requisite slice numbers to improve microscale characterization of absorbed dose inhomogeneities in αRPT.
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Affiliation(s)
- Robin Peter
- grid.47840.3f0000 0001 2181 7878Department of Nuclear Engineering, University of California, Berkeley, CA USA ,grid.266102.10000 0001 2297 6811Department of Radiology and Biomedical Imaging, University of California, San Francisco, CA USA
| | - Brenda M. Sandmaier
- grid.270240.30000 0001 2180 1622Fred Hutchinson Cancer Center, Seattle, WA USA ,grid.34477.330000000122986657Division of Medical Oncology, Department of Medicine, University of Washington, Seattle, WA USA
| | - Michael P. Dion
- grid.135519.a0000 0004 0446 2659Oak Ridge National Laboratory, Oak Ridge, TN USA
| | - Sofia H. L. Frost
- grid.270240.30000 0001 2180 1622Fred Hutchinson Cancer Center, Seattle, WA USA
| | - Erlinda B. Santos
- grid.270240.30000 0001 2180 1622Fred Hutchinson Cancer Center, Seattle, WA USA
| | - Aimee Kenoyer
- grid.270240.30000 0001 2180 1622Fred Hutchinson Cancer Center, Seattle, WA USA
| | - Donald K. Hamlin
- grid.34477.330000000122986657Department of Radiation Oncology, University of Washington, Seattle, WA USA
| | - D. Scott Wilbur
- grid.34477.330000000122986657Department of Radiation Oncology, University of Washington, Seattle, WA USA
| | - Robert D. Stewart
- grid.34477.330000000122986657Department of Radiation Oncology, University of Washington, Seattle, WA USA
| | | | - Kai Vetter
- grid.47840.3f0000 0001 2181 7878Department of Nuclear Engineering, University of California, Berkeley, CA USA
| | - Youngho Seo
- grid.47840.3f0000 0001 2181 7878Department of Nuclear Engineering, University of California, Berkeley, CA USA ,grid.266102.10000 0001 2297 6811Department of Radiology and Biomedical Imaging, University of California, San Francisco, CA USA
| | - Brian W. Miller
- grid.134563.60000 0001 2168 186XDepartment of Radiation Oncology, Department of Medical Imaging, College of Medicine, University of Arizona, Tucson, AZ USA
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Efficient Production of the PET Radionuclide 133La for Theranostic Purposes in Targeted Alpha Therapy Using the 134Ba(p,2n) 133La Reaction. Pharmaceuticals (Basel) 2022; 15:ph15101167. [PMID: 36297279 PMCID: PMC9611457 DOI: 10.3390/ph15101167] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Revised: 09/15/2022] [Accepted: 09/16/2022] [Indexed: 01/18/2023] Open
Abstract
Targeted Alpha Therapy is a research field of highest interest in specialized radionuclide therapy. Over the last decades, several alpha-emitting radionuclides have entered and left research topics towards their clinical translation. Especially, 225Ac provides all necessary physical and chemical properties for a successful clinical application, which has already been shown by [225Ac]Ac-PSMA-617. While PSMA-617 carries the DOTA moiety as the complexing agent, the chelator macropa as a macrocyclic alternative provides even more beneficial properties regarding labeling and complex stability in vivo. Lanthanum-133 is an excellent positron-emitting diagnostic lanthanide to radiolabel macropa-functionalized therapeutics since 133La forms a perfectly matched theranostic pair of radionuclides with the therapeutic radionuclide 225Ac, which itself can optimally be complexed by macropa as well. 133La was thus produced by cyclotron-based proton irradiation of an enriched 134Ba target. The target (30 mg of [134Ba]BaCO3) was irradiated for 60 min at 22 MeV and 10−15 µA beam current. Irradiation side products in the raw target solution were identified and quantified: 135La (0.4%), 135mBa (0.03%), 133mBa (0.01%), and 133Ba (0.0004%). The subsequent workup and anion-exchange-based product purification process took approx. 30 min and led to a total amount of (1.2−1.8) GBq (decay-corrected to end of bombardment) of 133La, formulated as [133La]LaCl3. After the complete decay of 133La, a remainder of ca. 4 kBq of long-lived 133Ba per 100 MBq of 133La was detected and rated as uncritical regarding personal dose and waste management. Subsequent radiolabeling was successfully performed with previously published macropa-derived PSMA inhibitors at a micromolar range (quantitative labeling at 1 µM) and evaluated by radio-TLC and radio-HPLC analyses. The scale-up to radioactivity amounts that are needed for clinical application purposes would be easy to achieve by increasing target mass, beam current, and irradiation time to produce 133La of high radionuclide purity (>99.5%) regarding labeling properties and side products.
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Personalized Dosimetry in the Context of Radioiodine Therapy for Differentiated Thyroid Cancer. Diagnostics (Basel) 2022; 12:diagnostics12071763. [PMID: 35885666 PMCID: PMC9320760 DOI: 10.3390/diagnostics12071763] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Revised: 07/15/2022] [Accepted: 07/19/2022] [Indexed: 12/02/2022] Open
Abstract
The most frequent thyroid cancer is Differentiated Thyroid Cancer (DTC) representing more than 95% of cases. A suitable choice for the treatment of DTC is the systemic administration of 131-sodium or potassium iodide. It is an effective tool used for the irradiation of thyroid remnants, microscopic DTC, other nonresectable or incompletely resectable DTC, or all the cited purposes. Dosimetry represents a valid tool that permits a tailored therapy to be obtained, sparing healthy tissue and so minimizing potential damages to at-risk organs. Absorbed dose represents a reliable indicator of biological response due to its correlation to tissue irradiation effects. The present paper aims to focus attention on iodine therapy for DTC treatment and has developed due to the urgent need for standardization in procedures, since no unique approaches are available. This review aims to summarize new proposals for a dosimetry-based therapy and so explore new alternatives that could provide the possibility to achieve more tailored therapies, minimizing the possible side effects of radioiodine therapy for Differentiated Thyroid Cancer.
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Hu A, Wilson JJ. Advancing Chelation Strategies for Large Metal Ions for Nuclear Medicine Applications. Acc Chem Res 2022; 55:904-915. [PMID: 35230803 DOI: 10.1021/acs.accounts.2c00003] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Nuclear medicine leverages radioisotopes of a wide range of elements, a significant portion of which are metals, for the diagnosis and treatment of disease. To optimally use radioisotopes of the metal ions, or radiometals, for these applications, a chelator that efficiently forms thermodynamically and kinetically stable complexes with them is required. The chelator also needs to attach to a biological targeting vector that locates pathological tissues. Numerous chelators suitable for small radiometals have been established to date, but chelators that work well for large radiometals are significantly less common. In this Account, we describe recent progress by us and others in the advancement of ligands for large radiometal chelation with emerging applications in nuclear medicine.First, we discuss and analyze the coordination chemistry of the chelator macropa, a macrocyclic ligand that contains the 18-crown-6 backbone and two picolinate pendent arms, with large metal ions in the context of nuclear medicine. This ligand is known for its unusual reverse size selectivity, the preference for binding large over small metal ions. The radiolabeling properties of macropa with large radiometals 225Ac3+, 132/135La3+, 131Ba2+, 223Ra2+, 213Bi3+, and related in vivo investigations are described. The development of macropa derivatives containing different pendent donors or rigidifying groups in the macrocyclic core is also briefly reviewed.Next, efforts to transform macropa into a radiopharmaceutical agent via covalent conjugation to biological targeting vectors are summarized. In this discussion, two types of bifunctional analogues of macropa reported in the literature, macropa-NCS and mcp-click, are presented. Their implementation in different radiopharmaceutical agents is discussed. Bioconjugates containing macropa attached to small-molecule targeting vectors or macromolecular antibodies are presented. The in vitro and in vivo evaluations of these constructs are also discussed.Lastly, chelators with dual size selectivity are described. This class of ligands exhibits good affinities for both large and small metal ions. This property is valuable for nuclear medicine applications that require the simultaneous chelation of both large and small radiometals with complementary therapeutic and diagnostic properties. Recently, we reported an 18-membered macrocyclic ligand called macrodipa that attains this selectivity pattern. This chelator, its second-generation analogue py-macrodipa, and their applications for chelating the medicinally relevant large 135La3+, 225Ac3+, 213Bi3+, and small 44Sc3+ ions are also presented. Studies with these radiometals show that py-macrodipa can effectively radiolabel and stably retain both large and small radiometals. Overall, this Account makes the case for innovative ligand design approaches for novel emerging radiometal ions with unusual coordination chemistry properties.
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Affiliation(s)
- Aohan Hu
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Justin J. Wilson
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
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Woods JJ, Unnerstall R, Hasson A, Abou DS, Radchenko V, Thorek DLJ, Wilson JJ. Stable Chelation of the Uranyl Ion by Acyclic Hexadentate Ligands: Potential Applications for 230U Targeted α-Therapy. Inorg Chem 2022; 61:3337-3350. [PMID: 35137587 PMCID: PMC9382226 DOI: 10.1021/acs.inorgchem.1c03972] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Uranium-230 is an α-emitting radionuclide with favorable properties for use in targeted α-therapy (TAT), a type of nuclear medicine that harnesses α particles to eradicate cancer cells. To successfully implement this radionuclide for TAT, a bifunctional chelator that can stably bind uranium in vivo is required. To address this need, we investigated the acyclic ligands H2dedpa, H2CHXdedpa, H2hox, and H2CHXhox as uranium chelators. The stability constants of these ligands with UO22+ were measured via spectrophotometric titrations, revealing log βML values that are greater than 18 and 26 for the "pa" and "hox" chelators, respectively, signifying that the resulting complexes are exceedingly stable. In addition, the UO22+ complexes were structurally characterized by NMR spectroscopy and X-ray crystallography. Crystallographic studies reveal that all six donor atoms of the four ligands span the equatorial plane of the UO22+ ion, giving rise to coordinatively saturated complexes that exclude solvent molecules. To further understand the enhanced thermodynamic stabilities of the "hox" chelators over the "pa" chelators, density functional theory (DFT) calculations were employed. The use of the quantum theory of atoms in molecules revealed that the extent of covalency between all four ligands and UO22+ was similar. Analysis of the DFT-computed ligand strain energy suggested that this factor was the major driving force for the higher thermodynamic stability of the "hox" ligands. To assess the suitability of these ligands for use with 230U TAT in vivo, their kinetic stabilities were probed by challenging the UO22+ complexes with the bone model hydroxyapatite (HAP) and human plasma. All four complexes were >95% stable in human plasma for 14 days, whereas in the presence of HAP, only the complexes of H2CHXdedpa and H2hox remained >80% intact over the same period. As a final validation of the suitability of these ligands for radiotherapy applications, the in vivo biodistribution of their UO22+ complexes was determined in mice in comparison to unchelated [UO2(NO3)2]. In contrast to [UO2(NO3)2], which displays significant bone uptake, all four ligand complexes do not accumulate in the skeletal system, indicating that they remain stable in vivo. Collectively, these studies suggest that the equatorial-spanning ligands H2dedpa, H2CHXdedpa, H2hox, and H2CHXhox are highly promising candidates for use in 230U TAT.
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Affiliation(s)
- Joshua J. Woods
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, 14853, USA
- Robert F. Smith School for Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY, 14853, USA
| | - Ryan Unnerstall
- Department of Radiology, Washington University School of Medicine, St. Louis, MO, 63110, USA
- Program in Quantitative Molecular Therapeutics, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Abbie Hasson
- Program in Quantitative Molecular Therapeutics, Washington University School of Medicine, St. Louis, MO, 63110, USA
- Department of Biomedical Engineering, Washington University, St. Louis, MO, 63110, USA
| | - Diane S. Abou
- Department of Radiology, Washington University School of Medicine, St. Louis, MO, 63110, USA
- Program in Quantitative Molecular Therapeutics, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Valery Radchenko
- Life Science Division, TRIUMF, Vancouver, BC Canada
- Chemistry Department, University of British Columbia, Vancouver, BC, BC V6T 2A3, Canada
| | - Daniel L. J. Thorek
- Department of Radiology, Washington University School of Medicine, St. Louis, MO, 63110, USA
- Program in Quantitative Molecular Therapeutics, Washington University School of Medicine, St. Louis, MO, 63110, USA
- Department of Biomedical Engineering, Washington University, St. Louis, MO, 63110, USA
| | - Justin J. Wilson
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, 14853, USA
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15
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Feasibility of a novel photoproduction of 225Ac and 227Th with natural thorium target. Sci Rep 2022; 12:372. [PMID: 35013619 PMCID: PMC8748787 DOI: 10.1038/s41598-021-04339-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Accepted: 12/20/2021] [Indexed: 12/01/2022] Open
Abstract
We propose an innovative way to produce both 225Ac and 227Th, two precious radioisotopes enabling promising targeted alpha therapy, in a natural thorium target bombarded with a 30–90 MeV electron beam. Bremsstrahlung photons in the target are analyzed by MCNP and in-situ photonuclear transmutation of 232Th is evaluated by using the TENDL nuclear data. In the photo-transmutation analysis, 13 nuclides including 229Th and 231Pa are modelled. Special procedures with chemical separations are also proposed to produce pure 225Ac and 227Th in separate streams. In addition, performance of the new approach is compared with conventional methods in terms of the 225Ac and 227Th yields. After a Th target is bombarded with a 500 kW electron beam for a year, yearly 225Ac yield is ~ 8.47 GBq (semi-permanently) and yearly 227Th yield is ~ 48.9 GBq over 50 years, and their yields are at least doubled in a 2-year irradiation. This work will help increase global supply of the two precious isotopes and would invariably help advance TAT-related researches and developments.
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16
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King AP, Lin FI, Escorcia FE. Why bother with alpha particles? Eur J Nucl Med Mol Imaging 2021; 49:7-17. [PMID: 34175980 DOI: 10.1007/s00259-021-05431-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2021] [Accepted: 05/24/2021] [Indexed: 12/23/2022]
Abstract
The approval of 223RaCl2 for cancer therapy in 2013 has heralded a resurgence of interest in the development of α-particle emitting radiopharmaceuticals. In the last decade, over a dozen α-emitting radiopharmaceuticals have entered clinical trials, spawned by strong preclinical studies. In this article, we explore the potential role of α-particle therapy in cancer treatment. We begin by providing a background for the basic principles of therapy with α-emitters, and we explore recent breakthroughs in therapy with α-emitting radionuclides, including conjugates with small molecules and antibodies. Finally, we discuss some outstanding challenges to the clinical adoption of α-therapies and potential strategies to address them.
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Affiliation(s)
- A Paden King
- Molecular Imaging Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20817, USA
- Radiation Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20817, USA
| | - Frank I Lin
- Molecular Imaging Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20817, USA
| | - Freddy E Escorcia
- Molecular Imaging Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20817, USA.
- Radiation Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20817, USA.
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17
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Hydroxypyridinones as a Very Promising Platform for Targeted Diagnostic and Therapeutic Radiopharmaceuticals. Molecules 2021. [DOI: 10.3390/molecules26226997
expr 973886017 + 973118332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/16/2023] Open
Abstract
Hydroxypyridinones (HOPOs) have been used in the chelation therapy of iron and actinide metals. Their application in metal-based radiopharmaceuticals has also been increasing in recent years. This review article focuses on how multidentate HOPOs can be used in targeted radiometal-based diagnostic and therapeutic radiopharmaceuticals. The general structure of radiometal-based targeted radiopharmaceuticals, a brief description of siderophores, the basic structure and properties of bidentate HOPO, some representative HOPO multidentate chelating agents, radiopharmaceuticals based on HOPO multidentate bifunctional chelators for gallium-68, thorium-227 and zirconium-89, as well as the future prospects of HOPO multidentate bifunctional chelators in other metal-based radiopharmaceuticals are described and discussed in turn. The HOPO metal-based radiopharmaceuticals that have shown good prospects in clinical and preclinical studies are gallium-68, thorium-227 and zirconium-89 radiopharmaceuticals. We expect HOPO multidentate bifunctional chelators to be a very promising platform for building novel targeted radiometal-based diagnostic and therapeutic radiopharmaceuticals.
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18
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Zhou X, Dong L, Shen L. Hydroxypyridinones as a Very Promising Platform for Targeted Diagnostic and Therapeutic Radiopharmaceuticals. Molecules 2021; 26:6997. [PMID: 34834087 PMCID: PMC8619595 DOI: 10.3390/molecules26226997&set/a 916769719+956065658] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/16/2023] Open
Abstract
Hydroxypyridinones (HOPOs) have been used in the chelation therapy of iron and actinide metals. Their application in metal-based radiopharmaceuticals has also been increasing in recent years. This review article focuses on how multidentate HOPOs can be used in targeted radiometal-based diagnostic and therapeutic radiopharmaceuticals. The general structure of radiometal-based targeted radiopharmaceuticals, a brief description of siderophores, the basic structure and properties of bidentate HOPO, some representative HOPO multidentate chelating agents, radiopharmaceuticals based on HOPO multidentate bifunctional chelators for gallium-68, thorium-227 and zirconium-89, as well as the future prospects of HOPO multidentate bifunctional chelators in other metal-based radiopharmaceuticals are described and discussed in turn. The HOPO metal-based radiopharmaceuticals that have shown good prospects in clinical and preclinical studies are gallium-68, thorium-227 and zirconium-89 radiopharmaceuticals. We expect HOPO multidentate bifunctional chelators to be a very promising platform for building novel targeted radiometal-based diagnostic and therapeutic radiopharmaceuticals.
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Affiliation(s)
- Xu Zhou
- HTA Co., Ltd., Beijing 102413, China;
- China Isotope & Radiation Corporation, Beijing 100089, China;
| | - Linlin Dong
- China Isotope & Radiation Corporation, Beijing 100089, China;
| | - Langtao Shen
- HTA Co., Ltd., Beijing 102413, China;
- China Isotope & Radiation Corporation, Beijing 100089, China;
- National Isotope Center of Engineering and Technology, China Institute of Atomic Energy, Beijing 102413, China
- Correspondence:
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19
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Zhou X, Dong L, Shen L. Hydroxypyridinones as a Very Promising Platform for Targeted Diagnostic and Therapeutic Radiopharmaceuticals. Molecules 2021; 26:6997. [PMID: 34834087 PMCID: PMC8619595 DOI: 10.3390/molecules26226997] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2021] [Revised: 11/13/2021] [Accepted: 11/17/2021] [Indexed: 01/30/2023] Open
Abstract
Hydroxypyridinones (HOPOs) have been used in the chelation therapy of iron and actinide metals. Their application in metal-based radiopharmaceuticals has also been increasing in recent years. This review article focuses on how multidentate HOPOs can be used in targeted radiometal-based diagnostic and therapeutic radiopharmaceuticals. The general structure of radiometal-based targeted radiopharmaceuticals, a brief description of siderophores, the basic structure and properties of bidentate HOPO, some representative HOPO multidentate chelating agents, radiopharmaceuticals based on HOPO multidentate bifunctional chelators for gallium-68, thorium-227 and zirconium-89, as well as the future prospects of HOPO multidentate bifunctional chelators in other metal-based radiopharmaceuticals are described and discussed in turn. The HOPO metal-based radiopharmaceuticals that have shown good prospects in clinical and preclinical studies are gallium-68, thorium-227 and zirconium-89 radiopharmaceuticals. We expect HOPO multidentate bifunctional chelators to be a very promising platform for building novel targeted radiometal-based diagnostic and therapeutic radiopharmaceuticals.
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Affiliation(s)
- Xu Zhou
- HTA Co., Ltd., Beijing 102413, China;
- China Isotope & Radiation Corporation, Beijing 100089, China;
| | - Linlin Dong
- China Isotope & Radiation Corporation, Beijing 100089, China;
| | - Langtao Shen
- HTA Co., Ltd., Beijing 102413, China;
- China Isotope & Radiation Corporation, Beijing 100089, China;
- National Isotope Center of Engineering and Technology, China Institute of Atomic Energy, Beijing 102413, China
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20
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Bagus PS, Schacherl B, Vitova T. Computational and Spectroscopic Tools for the Detection of Bond Covalency in Pu(IV) Materials. Inorg Chem 2021; 60:16090-16102. [PMID: 34634201 PMCID: PMC8564760 DOI: 10.1021/acs.inorgchem.1c01331] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Plutonium is used as a major component of new-generation nuclear fuels and of radioisotope batteries for Mars rovers, but it is also an environmental pollutant. Plutonium clearly has high technological and environmental importance, but it has an extremely complex, not well-understood electronic structure. The level of covalency of the Pu 5f valence orbitals and their role in chemical bonding are still an enigma and thus at the frontier of research in actinide science. We performed fully relativistic quantum chemical computations of the electronic structure of the Pu4+ ion and the PuO2 compound. Using four different theoretical tools, it is shown that the 5f orbitals have very little covalent character although the 5f(7/2) a2u orbital with the highest orbital energy has the greatest extent of covalency in PuO2. It is illustrated that the Pu M4,5 edge high-energy resolution X-ray absorption near-edge structure (Pu M4,5 HR-XANES) spectra cannot be interpreted in terms of dipole selection rules applied between individual 3d and 5f orbitals, but the selection rules must be applied between the total wavefunctions for the initial and excited states. This is because the states cannot be represented by single determinants. They are shown to involve major redistributions on the 5f electrons over the different 5f orbitals. These redistributions could be viewed as shake-up-like excitations in the 5f shell from the lowest orbital energy from J = 5f(5/2) into higher orbital energy J = 5f(7/2). We show that the second peak in the Pu M4 edge and the high-energy shoulder of the Pu M5 edge HR-XANES spectra probe the 5f(7/2) a2u orbital; thus, these spectral features are expected to change upon bond variations. We describe theoretical and spectroscopy tools, which can be applied for all actinide elements in materials with cubic structure.
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Affiliation(s)
- Paul S Bagus
- Department of Chemistry, University of North Texas, Denton, Texas 76203-5017, United States
| | - Bianca Schacherl
- Karlsruhe Institute of Technology (KIT), Institute for Nuclear Waste Disposal (INE), P.O. Box 3640, D-76021 Karlsruhe, Germay
| | - Tonya Vitova
- Karlsruhe Institute of Technology (KIT), Institute for Nuclear Waste Disposal (INE), P.O. Box 3640, D-76021 Karlsruhe, Germay
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21
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Eychenne R, Chérel M, Haddad F, Guérard F, Gestin JF. Overview of the Most Promising Radionuclides for Targeted Alpha Therapy: The "Hopeful Eight". Pharmaceutics 2021; 13:pharmaceutics13060906. [PMID: 34207408 PMCID: PMC8234975 DOI: 10.3390/pharmaceutics13060906] [Citation(s) in RCA: 74] [Impact Index Per Article: 24.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Revised: 06/02/2021] [Accepted: 06/08/2021] [Indexed: 12/11/2022] Open
Abstract
Among all existing radionuclides, only a few are of interest for therapeutic applications and more specifically for targeted alpha therapy (TAT). From this selection, actinium-225, astatine-211, bismuth-212, bismuth-213, lead-212, radium-223, terbium-149 and thorium-227 are considered as the most suitable. Despite common general features, they all have their own physical characteristics that make them singular and so promising for TAT. These radionuclides were largely studied over the last two decades, leading to a better knowledge of their production process and chemical behavior, allowing for an increasing number of biological evaluations. The aim of this review is to summarize the main properties of these eight chosen radionuclides. An overview from their availability to the resulting clinical studies, by way of chemical design and preclinical studies is discussed.
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Affiliation(s)
- Romain Eychenne
- Groupement d’Intérêt Public ARRONAX, 1 Rue Aronnax, F-44817 Saint-Herblain, France;
- Université de Nantes, Inserm, CNRS, Centre de Recherche en Cancérologie et Immunologie Nantes—Angers (CRCINA)—UMR 1232, ERL 6001, F-44000 Nantes, France; (M.C.); (F.G.)
- Correspondence: (R.E.); (J.-F.G.)
| | - Michel Chérel
- Université de Nantes, Inserm, CNRS, Centre de Recherche en Cancérologie et Immunologie Nantes—Angers (CRCINA)—UMR 1232, ERL 6001, F-44000 Nantes, France; (M.C.); (F.G.)
| | - Férid Haddad
- Groupement d’Intérêt Public ARRONAX, 1 Rue Aronnax, F-44817 Saint-Herblain, France;
- Laboratoire Subatech, UMR 6457, Université de Nantes, IMT Atlantique, CNRS, Subatech, F-44000 Nantes, France
| | - François Guérard
- Université de Nantes, Inserm, CNRS, Centre de Recherche en Cancérologie et Immunologie Nantes—Angers (CRCINA)—UMR 1232, ERL 6001, F-44000 Nantes, France; (M.C.); (F.G.)
| | - Jean-François Gestin
- Université de Nantes, Inserm, CNRS, Centre de Recherche en Cancérologie et Immunologie Nantes—Angers (CRCINA)—UMR 1232, ERL 6001, F-44000 Nantes, France; (M.C.); (F.G.)
- Correspondence: (R.E.); (J.-F.G.)
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22
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Herrero Álvarez N, Bauer D, Hernández-Gil J, Lewis JS. Recent Advances in Radiometals for Combined Imaging and Therapy in Cancer. ChemMedChem 2021; 16:2909-2941. [PMID: 33792195 DOI: 10.1002/cmdc.202100135] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Indexed: 12/14/2022]
Abstract
Nuclear medicine is defined as the use of radionuclides for diagnostic and therapeutic applications. The imaging modalities positron emission tomography (PET) and single-photon emission computed tomography (SPECT) are based on γ-emissions of specific energies. The therapeutic technologies are based on β- -particle-, α-particle-, and Auger electron emitters. In oncology, PET and SPECT are used to detect cancer lesions, to determine dosimetry, and to monitor therapy effectiveness. In contrast, radiotherapy is designed to irreparably damage tumor cells in order to eradicate or control the disease's progression. Radiometals are being explored for the development of diagnostic and therapeutic radiopharmaceuticals. Strategies that combine both modalities (diagnostic and therapeutic), referred to as theranostics, are promising candidates for clinical applications. This review provides an overview of the basic concepts behind therapeutic and diagnostic radiopharmaceuticals and their significance in contemporary oncology. Select radiometals that significantly impact current and upcoming cancer treatment strategies are grouped as clinically suitable theranostics pairs. The most important physical and chemical properties are discussed. Standard production methods and current radionuclide availability are provided to indicate whether a cost-efficient use in a clinical routine is feasible. Recent preclinical and clinical developments and outline perspectives for the radiometals are highlighted in each section.
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Affiliation(s)
- Natalia Herrero Álvarez
- Department of Radiology, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY, 10065, USA
| | - David Bauer
- Department of Radiology, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY, 10065, USA
| | - Javier Hernández-Gil
- Department of Radiology, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY, 10065, USA.,Biomedical MRI/MoSAIC, Department of Imaging and Pathology, Katholieke Universiteit, Herestraat 49, 3000, Leuven, Belgium
| | - Jason S Lewis
- Department of Radiology, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY, 10065, USA.,Department of Radiology, Weill Cornell Medical College, 1300 York Avenue, New York, NY, 10065, USA.,Department of Pharmacology, Weill-Cornell Medical College, New York, NY, 10065, USA
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23
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Cytawa W, Hartrampf P, Lass P, Kircher M, Polat B, Buck AK, Lapa C. PSMA Theranostics: A "Must Have" in Every Prostate Cancer Center. Illustration of Two Clinical Cases and Review of the Literature. Clin Genitourin Cancer 2021; 19:e235-e247. [PMID: 33906800 DOI: 10.1016/j.clgc.2021.03.008] [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: 11/05/2020] [Revised: 02/14/2021] [Accepted: 03/03/2021] [Indexed: 12/20/2022]
Abstract
This manuscript describes the history of 2 patients with prostate cancer (PCa) and the role of prostate-specific membrane antigen (PSMA) theranostics in their clinical management. In the first patient, PSMA-directed positron emission tomography (PET)/computed tomography (CT) imaging was used for primary staging of high-risk PCa before initial therapy. Then after biochemical relapse it was used to plan the scope of further treatment, in which it allowed among others to perform precise target volume delineation for salvage radiotherapy for pathologic lymph nodes. In the second patient with metastatic castration-resistant prostate cancer (mCRPC), PSMA-guided imaging played a key role in the qualification for PSMA-directed radioligand therapy (RLT) with lutetium-177. We also present a review of the current literature concerning PSMA theranostics in the 2 clinical settings, ie, primary staging of PCa and PSMA RLT of mCRPC. In the first part of the review, we report on the diagnostic efficacy of various PSMA imaging radiotracers labeled with gallium-68, fluorine-18, and technetium-99m. In the second part, we describe the limitations and future perspectives of PSMA therapeutic radiopharmaceuticals, including various beta(-) and alpha emitters.
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Affiliation(s)
- Wojciech Cytawa
- Department of Nuclear Medicine, Medical University of Gdańsk, Gdańsk, Poland; Department of Nuclear Medicine, University Hospital Würzburg, Würzburg, Germany.
| | - Philipp Hartrampf
- Department of Nuclear Medicine, University Hospital Würzburg, Würzburg, Germany
| | - Piotr Lass
- Department of Nuclear Medicine, Medical University of Gdańsk, Gdańsk, Poland
| | - Malte Kircher
- Nuclear Medicine, Medical Faculty, University of Augsburg, Augsburg, Germany
| | - Bülent Polat
- Department of Radiation Oncology, University Hospital Würzburg, Würzburg, Germany
| | - Andreas K Buck
- Department of Nuclear Medicine, University Hospital Würzburg, Würzburg, Germany
| | - Constantin Lapa
- Nuclear Medicine, Medical Faculty, University of Augsburg, Augsburg, Germany
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24
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Juzeniene A, Stenberg VY, Bruland ØS, Larsen RH. Preclinical and Clinical Status of PSMA-Targeted Alpha Therapy for Metastatic Castration-Resistant Prostate Cancer. Cancers (Basel) 2021; 13:779. [PMID: 33668474 PMCID: PMC7918517 DOI: 10.3390/cancers13040779] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Revised: 02/07/2021] [Accepted: 02/08/2021] [Indexed: 12/14/2022] Open
Abstract
Bone, lymph node, and visceral metastases are frequent in castrate-resistant prostate cancer patients. Since such patients have only a few months' survival benefit from standard therapies, there is an urgent need for new personalized therapies. The prostate-specific membrane antigen (PSMA) is overexpressed in prostate cancer and is a molecular target for imaging diagnostics and targeted radionuclide therapy (theragnostics). PSMA-targeted α therapies (PSMA-TAT) may deliver potent and local radiation more selectively to cancer cells than PSMA-targeted β- therapies. In this review, we summarize both the recent preclinical and clinical advances made in the development of PSMA-TAT, as well as the availability of therapeutic α-emitting radionuclides, the development of small molecules and antibodies targeting PSMA. Lastly, we discuss the potentials, limitations, and future perspectives of PSMA-TAT.
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Affiliation(s)
- Asta Juzeniene
- Department of Radiation Biology, Institute for Cancer Research, Norwegian Radium Hospital, Oslo University Hospital, Montebello, 0379 Oslo, Norway;
| | - Vilde Yuli Stenberg
- Department of Radiation Biology, Institute for Cancer Research, Norwegian Radium Hospital, Oslo University Hospital, Montebello, 0379 Oslo, Norway;
- Nucligen, Ullernchausséen 64, 0379 Oslo, Norway;
- Institute for Clinical Medicine, University of Oslo, Box 1171 Blindern, 0318 Oslo, Norway;
| | - Øyvind Sverre Bruland
- Institute for Clinical Medicine, University of Oslo, Box 1171 Blindern, 0318 Oslo, Norway;
- Department of Oncology, Norwegian Radium Hospital, Oslo University Hospital, 0379 Oslo, Norway
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Grieve ML, Paterson BM. The Evolving Coordination Chemistry of Radiometals for Targeted Alpha Therapy. Aust J Chem 2021. [DOI: 10.1071/ch21184] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Role of Her-2 in Gastrointestinal Tumours beyond Gastric Cancer: A Tool for Precision Medicine. GASTROINTESTINAL DISORDERS 2020. [DOI: 10.3390/gidisord3010001] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Gastrointestinal (GI) tumors account for a quarter of all the cancer burden and a third of the global cancer-related mortality. Among them, some cancers retain a dismal prognosis; therefore, newer and innovative therapies are urgently needed in priority disease areas of high-unmet medical need. In this context, HER2 could be a relevant prognostic and predictive biomarker acting as a target for specific drugs. However, if the role of HER2 has been object of investigation for several years in gastric cancer, it is not well established in other GI malignancies. The aim of this narrative review was to portray the current landscape of the potential role of HER2 as a predictive biomarker for GI tumors beyond gastric cancer. In colon cancer, the benefit from anti-HER2 therapies is less clear than in gastric neoplasms for the lack of controlled studies. Pancreatic, biliary tract adenocarcinomas and hepatocarcinoma may derive a less clear clinical benefit by using anti-HER2 agents in HER2 positive tumors. Overall, the results are promising and seem to suggest that the integration of multiple modalities of therapies can optimize the cancer care. However, further prospective trials are needed to validate the use of personalized targeted therapies in this field.
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Filippi L, Chiaravalloti A, Schillaci O, Bagni O. The potential of PSMA-targeted alpha therapy in the management of prostate cancer. Expert Rev Anticancer Ther 2020; 20:823-829. [PMID: 32820953 DOI: 10.1080/14737140.2020.1814151] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
INTRODUCTION Alpha emitters present several advantages for cancer therapy. The radiopharmaceutical 223Ra-dichloride has been recently introduced for the targeted alpha therapy (TAT) of metastastic castration-resistant prostate cancer (mCRPC). However, since 223Ra-dichloride targets only skeletal lesions, its use in clinical practice is recommended only in subjects without visceral metastases. To overcome this, several efforts have been made to develop radiopharmaceuticals suitable for TAT and specifically directed toward the biomarker prostate specific membrane antigen (PSMA), overexpressed by both skeletal and visceral metastases from mCRPC. AREAS COVERED The radiobiological principles concerning TAT applications are covered, with particular emphasis on its pros and cons, especially in comparison with beta-emitter radionuclide therapy. Furthermore, the role of PSMA as a theranostic target for imaging and therapy is reviewed. Lastly, the pre-clinical and clinical applications of TAT through 225Actinium (225AC) and 213Bismuth (213Bi) are discussed. EXPERT OPINION PSMA-based TAT holds the promise of becoming a powerful tool for the management of mCRPC. Nevertheless, several issues have still to be addressed, especially concerning TAT toxicity. Furthermore, several efforts have to be made for identifying the more adequate alpha-emitter (225Ac vs 213Bi) with a view to the patient's tailored therapeutic approach.
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Affiliation(s)
- Luca Filippi
- Department of Nuclear Medicine, Santa Maria Goretti Hospital , Latina, Italy
| | - Agostino Chiaravalloti
- Department of Biomedicine and Prevention, University Tor Vergata , Rome, Italy.,IRCCS Neuromed , Pozzilli, Italy
| | - Orazio Schillaci
- Department of Biomedicine and Prevention, University Tor Vergata , Rome, Italy.,IRCCS Neuromed , Pozzilli, Italy
| | - Oreste Bagni
- Department of Nuclear Medicine, Santa Maria Goretti Hospital , Latina, Italy
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Abstract
Abstract
Purpose
The aim of this review is to summarize the main applications of mesothelin-targeting agents in the diagnosis of different types of cancers with a brief mention of nuclear magnetic resonance.
Methods
The articles taken into account were selected from PubMed, Scopus, and Web of Sciences, including research articles and abstracts that deal with radioimmunotherapy and new tracers for nuclear medicine and radiodiagnosis. Articles that are not in English have been excluded.
Results
Mesothelin-targeting agents were the subject of the selected articles in which tracers as 64Cu-DOTA-11-25mAb anti MSLN, 111In-MORAb-009-CHX-A″, 89Zr-MMOT0530A, 111In-amatuximab, 99mTc-A1, 89Zr-AMA, 89Zr-amatuximab, 64Cu-amatuximab, 89Zr-labeled MMOT0530A and 89Zr-B3 found application in detection of malignancies that overexpressed mesothelin. Only one article approached magnetic resonance imaging (MRI) diagnosis using superparamagnetic iron oxide nanoparticles linked to anti-mesothelin antibodies. The tracers proved to be highly sensitive in detecting mesothelin positive cells. 89Zr-labeled MMOT0530A could also be used to predict the suitability of patients to radioimmunotherapy.
Conclusions
Radiolabeled anti-mesothelin antibodies could be crucial as a treatment tool and for predicting the eligibility and the response of the patient to radioimmunotherapy through the study of the expression grade of mesothelin. They can be a relevant tool for pancreatic adenocarcinoma, lung cancer, human epidermoid carcinoma, ovarian cancer, malignant mesothelioma in which mesothelin is widely expressed.
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Guerra Liberal FDC, O'Sullivan JM, McMahon SJ, Prise KM. Targeted Alpha Therapy: Current Clinical Applications. Cancer Biother Radiopharm 2020; 35:404-417. [PMID: 32552031 DOI: 10.1089/cbr.2020.3576] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
α-Emitting radionuclides have been approved for cancer treatment since 2013, with increasing degrees of success. Despite this clinical utility, little is known regarding the mechanisms of action of α particles in this setting, and accurate assessments of the dosimetry underpinning their effectiveness are lacking. However, targeted alpha therapy (TAT) is gaining more attention as new targets, synthetic chemistry approaches, and α particle emitters are identified, constructed, developed, and realized. From a radiobiological perspective, α particles are more effective at killing cells compared to low linear energy transfer radiation. Also, from these direct effects, it is now evident from preclinical and clinical data that α emitters are capable of both producing effects in nonirradiated bystander cells and stimulating the immune system, extending the biological effects of TAT beyond the range of α particles. The short range of α particles makes them a potent tool to irradiate single-cell lesions or treat solid tumors by minimizing unwanted irradiation of normal tissue surrounding the cancer cells, assuming a high specificity of the radiopharmaceutical and good stability of its chemical bonds. Clinical approval of 223RaCl2 in 2013 was a major milestone in the widespread application of TAT as a safe and effective strategy for cancer treatment. In addition, 225Ac-prostate specific membrane antigen treatment benefit in metastatic castrate-resistant prostate cancer patients, refractory to standard therapies, is another game-changing piece in the short history of TAT clinical application. Clinical applications of TAT are growing with different radionuclides and combination therapies, and in different clinical settings. Despite the remarkable advances in TAT dosimetry and imaging, it has not yet been used to its full potential. Labeled 227Th and 225Ac appear to be promising candidates and could represent the next generation of agents able to extend patient survival in several clinical scenarios.
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Affiliation(s)
- Francisco D C Guerra Liberal
- The Patrick G Johnston Centre for Cancer Research, Queen's University Belfast, Belfast, United Kingdom.,Faculdade de Ciências e Tenclonogia, Universidade Nova de Lisboa, Caparica, Portugal
| | - Joe M O'Sullivan
- The Patrick G Johnston Centre for Cancer Research, Queen's University Belfast, Belfast, United Kingdom.,Clinical Oncology, Northern Ireland Cancer Centre, Belfast Health and Social Care Trust, Belfast, United Kingdom
| | - Stephen J McMahon
- The Patrick G Johnston Centre for Cancer Research, Queen's University Belfast, Belfast, United Kingdom
| | - Kevin M Prise
- The Patrick G Johnston Centre for Cancer Research, Queen's University Belfast, Belfast, United Kingdom
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Atomic Nanogenerators in Targeted Alpha Therapies: Curie's Legacy in Modern Cancer Management. Pharmaceuticals (Basel) 2020; 13:ph13040076. [PMID: 32340103 PMCID: PMC7243103 DOI: 10.3390/ph13040076] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Revised: 04/17/2020] [Accepted: 04/21/2020] [Indexed: 12/12/2022] Open
Abstract
Atomic in vivo nanogenerators such as actinium-225, thorium-227, and radium-223 are of increasing interest and importance in the treatment of patients with metastatic cancer diseases. This is due to their peculiar physical, chemical, and biological characteristics, leading to astonishing responses in otherwise resistant patients. Nevertheless, there are still a few obstacles and hurdles to be overcome that hamper the broader utilization in the clinical setting. Next to the limited supply and relatively high costs, the in vivo complex stability and the fate of the recoiling daughter radionuclides are substantial problems that need to be solved. In radiobiology, the mechanisms underlying treatment efficiency, possible resistance mechanisms, and late side effect occurrence are still far from being understood and need to be unraveled. In this review, the current knowledge on the scientific and clinical background of targeted alpha therapies is summarized. Furthermore, open issues and novel approaches with a focus on the future perspective are discussed. Once these are unraveled, targeted alpha therapies with atomic in vivo nanogenerators can be tailored to suit the needs of each patient when applying careful risk stratification and combination therapies. They have the potential to become one of the major treatment pillars in modern cancer management.
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