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Cheng MH, Xie LJ. Synthesis and Biologic Evaluation of an Iodine-Labeled Entecavir Derivative for Anti-hepatitis B Virus Activity. Nucl Med Mol Imaging 2024; 58:279-290. [PMID: 39036458 PMCID: PMC11254891 DOI: 10.1007/s13139-024-00849-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2023] [Revised: 01/25/2024] [Accepted: 01/31/2024] [Indexed: 07/23/2024] Open
Abstract
Purpose To label entecavir (ETV) with radioiodine and evaluate its effect on inhibiting hepatitis B virus (HBV) secretion and replication in vitro as well as its biodistribution in BALB/c mice. Methods 125I-ETV was synthesized via binding a vinyl tributyltin group to ETV and producing electrophilic iodination of the group. Its chemical properties were assessed using traditional methods. Upon intravenous injection of 125I-ETV into BALB/c mice, the radioactivity of the critical organs was detected. In vitro, the anti-HBV activity of 125I-ETV was investigated using HepG2.2.15 cell culture model. Confocal microscopy was used to analyze the cell apoptosis. Culture supernatant samples were used for measuring HBV surface antigen (HBsAg) and HBV e antigen (HBeAg) by enzyme-linked immunosorbent assay. Intracellular HBV pregenomic RNA (pgRNA), DNA, and covalently closed circular DNA (cccDNA) were measured by real-time fluorescence quantitative PCR. Results The radiochemical purity of 125I-ETV was greater than 95% after incubation in freshly serum within 48 h. The three highest radioactivities were in the stomach, intestine, and liver after intravenous injection at 0.5 h, 2 h, and 24 h. The confocal fluorescence imaging showed that 125I-ETV did not induce cell apoptosis after treatment for 96 h. 125I-ETV decreases HBsAg and HBeAg secretions as well as intracellular HBV pgRNA, DNA, and cccDNA copies in a dose-dependent manner. Moreover, the anti-HBV activity of 125I-ETV is greater than that of ETV. Conclusions The study outcome establishes 125I-ETV as a candidate for anti-HBV. However, it is still in need of further endorsement and optimization by animal model studies before using 125I-ETV to treat chronic HBV disease.
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Affiliation(s)
- Mu hua Cheng
- Department of Nuclear Medicine, Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou City, Guangdong Province China
| | - Liang jun Xie
- Department of Nuclear Medicine, Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou City, Guangdong Province China
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2
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Fonseca Cabrera GO, Ma X, Lin W, Zhang T, Zhao W, Pan L, Li X, Barnhart TE, Aluicio-Sarduy E, Deng H, Wu X, Rakesh KP, Li Z, Engle JW, Wu Z. Synthesis of 64Cu-, 55Co-, and 68Ga-Labeled Radiopharmaceuticals Targeting Neurotensin Receptor-1 for Theranostics: Adjusting In Vivo Distribution Using Multiamine Macrocycles. J Nucl Med 2024; 65:1250-1256. [PMID: 38871388 PMCID: PMC11294072 DOI: 10.2967/jnumed.124.267469] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Accepted: 05/07/2024] [Indexed: 06/15/2024] Open
Abstract
The development of theranostic radiotracers relies on their binding to specific molecular markers of a particular disease and the use of corresponding radiopharmaceutical pairs thereafter. This study reports the use of multiamine macrocyclic moieties (MAs), as linkers or chelators, in tracers targeting the neurotensin receptor-1 (NTSR-1). The goal is to achieve elevated tumor uptake, minimal background interference, and prolonged tumor retention in NTSR-1-positive tumors. Methods: We synthesized a series of neurotensin antagonists bearing MA linkers and metal chelators. The MA unit is hypothesized to establish a strong interaction with the cell membrane, and the addition of a second chelator may enhance water solubility, consequently reducing liver uptake. Small-animal PET/CT imaging of [64Cu]Cu-DOTA-SR-3MA, [64Cu]Cu-NT-CB-NOTA, [68Ga]Ga-NT-CB-NOTA, [64Cu]Cu-NT-CB-DOTA, and [64Cu]Cu-NT-Sarcage was acquired at 1, 4, 24, and 48 h after injection using H1299 tumor models. [55Co]Co-NT-CB-NOTA was also tested in HT29 (high NTSR-1 expression) and Caco2 (low NTSR-1 expression) colorectal adenocarcinoma tumor models. Saturation binding assay and internalization of [55Co]Co-NT-CB-NOTA were used to test tracer specificity and internalization in HT29 cells. Results: In vivo PET imaging with [64Cu]Cu-NT-CB-NOTA, [68Ga]Ga-NT-CB-NOTA, and [55Co]Co-NT-CB-NOTA revealed high tumor uptake, high tumor-to-background contrast, and sustained tumor retention (≤48 h after injection) in NTSR-1-positive tumors. Tumor uptake of [64Cu]Cu-NT-CB-NOTA remained at 76.9% at 48 h after injection compared with uptake 1 h after injection in H1299 tumor models, and [55Co]Co-NT-CB-NOTA was retained at 60.2% at 24 h compared with uptake 1 h after injection in HT29 tumor models. [64Cu]Cu-NT-Sarcage also showed high tumor uptake with low background and high tumor retention 48 h after injection Conclusion: Tumor uptake and pharmacokinetic properties of NTSR-1-targeting radiopharmaceuticals were greatly improved when attached with different nitrogen-containing macrocyclic moieties. The study results suggest that NT-CB-NOTA labeled with either 64Cu/67Cu, 55Co/58mCo, or 68Ga (effect of 177Lu in tumor to be determined in future studies) and NT-Sarcage labeled with 64Cu/67Cu or 55Co/58mCo may be excellent diagnostic and therapeutic radiopharmaceuticals targeting NTSR-1-positive cancers. Also, the introduction of MA units to other ligands is warranted in future studies to test the generality of this approach.
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Affiliation(s)
- German O Fonseca Cabrera
- Biomedical Research Imaging Center, Department of Radiology, UNC Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Xinrui Ma
- Biomedical Research Imaging Center, Department of Radiology, UNC Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
- Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill and North Carolina State University, Chapel Hill, North Carolina
| | - Wilson Lin
- Department of Medical Physics, University of Wisconsin, Madison, Wisconsin; and
| | - Tao Zhang
- Biomedical Research Imaging Center, Department of Radiology, UNC Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Weiling Zhao
- Biomedical Research Imaging Center, Department of Radiology, UNC Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Liqin Pan
- Biomedical Research Imaging Center, Department of Radiology, UNC Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Xiaomei Li
- Accunovo Biotechnologies, Inc., Chapel Hill, North Carolina
| | - Todd E Barnhart
- Department of Medical Physics, University of Wisconsin, Madison, Wisconsin; and
| | | | - Huaifu Deng
- Biomedical Research Imaging Center, Department of Radiology, UNC Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Xuedan Wu
- Biomedical Research Imaging Center, Department of Radiology, UNC Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Kadalipura P Rakesh
- Biomedical Research Imaging Center, Department of Radiology, UNC Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Zibo Li
- Biomedical Research Imaging Center, Department of Radiology, UNC Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina;
| | - Jonathan W Engle
- Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill and North Carolina State University, Chapel Hill, North Carolina;
| | - Zhanhong Wu
- Biomedical Research Imaging Center, Department of Radiology, UNC Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina;
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Şan H, Bayrakcı Ö, Çağdaş B, Serdengeçti M, Alagöz E. Reliability and readability analysis of ChatGPT-4 and Google Bard as a patient information source for the most commonly applied radionuclide treatments in cancer patients. Rev Esp Med Nucl Imagen Mol 2024; 43:500021. [PMID: 38821410 DOI: 10.1016/j.remnie.2024.500021] [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: 04/16/2024] [Accepted: 05/21/2024] [Indexed: 06/02/2024]
Abstract
PURPOSE Searching for online health information is a popular approach employed by patients to enhance their knowledge for their diseases. Recently developed AI chatbots are probably the easiest way in this regard. The purpose of the study is to analyze the reliability and readability of AI chatbot responses in terms of the most commonly applied radionuclide treatments in cancer patients. METHODS Basic patient questions, thirty about RAI, PRRT and TARE treatments and twenty-nine about PSMA-TRT, were asked one by one to GPT-4 and Bard on January 2024. The reliability and readability of the responses were assessed by using DISCERN scale, Flesch Reading Ease(FRE) and Flesch-Kincaid Reading Grade Level(FKRGL). RESULTS The mean (SD) FKRGL scores for the responses of GPT-4 and Google Bard about RAI, PSMA-TRT, PRRT and TARE treatmens were 14.57 (1.19), 14.65 (1.38), 14.25 (1.10), 14.38 (1.2) and 11.49 (1.59), 12.42 (1.71), 11.35 (1.80), 13.01 (1.97), respectively. In terms of readability the FRKGL scores of the responses of GPT-4 and Google Bard about RAI, PSMA-TRT, PRRT and TARE treatments were above the general public reading grade level. The mean (SD) DISCERN scores assesses by nuclear medicine phsician for the responses of GPT-4 and Bard about RAI, PSMA-TRT, PRRT and TARE treatments were 47.86 (5.09), 48.48 (4.22), 46.76 (4.09), 48.33 (5.15) and 51.50 (5.64), 53.44 (5.42), 53 (6.36), 49.43 (5.32), respectively. Based on mean DISCERN scores, the reliability of the responses of GPT-4 and Google Bard about RAI, PSMA-TRT, PRRT, and TARE treatments ranged from fair to good. The inter-rater reliability correlation coefficient of DISCERN scores assessed by GPT-4, Bard and nuclear medicine physician for the responses of GPT-4 about RAI, PSMA-TRT, PRRT and TARE treatments were 0.512(95% CI 0.296: 0.704), 0.695(95% CI 0.518: 0.829), 0.687(95% CI 0.511: 0.823) and 0.649 (95% CI 0.462: 0.798), respectively (p < 0.01). The inter-rater reliability correlation coefficient of DISCERN scores assessed by GPT-4, Bard and nuclear medicine physician for the responses of Bard about RAI, PSMA-TRT, PRRT and TARE treatments were 0.753(95% CI 0.602: 0.863), 0.812(95% CI 0.686: 0.899), 0.804(95% CI 0.677: 0.894) and 0.671 (95% CI 0.489: 0.812), respectively (p < 0.01). The inter-rater reliability for the responses of Bard and GPT-4 about RAİ, PSMA-TRT, PRRT and TARE treatments were moderate to good. Further, consulting to the nuclear medicine physician was rarely emphasized both in GPT-4 and Google Bard and references were included in some responses of Google Bard, but there were no references in GPT-4. CONCLUSION Although the information provided by AI chatbots may be acceptable in medical terms, it can not be easy to read for the general public, which may prevent it from being understandable. Effective prompts using 'prompt engineering' may refine the responses in a more comprehensible manner. Since radionuclide treatments are specific to nuclear medicine expertise, nuclear medicine physician need to be stated as a consultant in responses in order to guide patients and caregivers to obtain accurate medical advice. Referencing is significant in terms of confidence and satisfaction of patients and caregivers seeking information.
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Affiliation(s)
- Hüseyin Şan
- Ankara Bilkent City Hospital, Department of Nuclear Medicine, Ankara, Turkey.
| | - Özkan Bayrakcı
- Ankara Bilkent City Hospital, Department of Nuclear Medicine, Ankara, Turkey
| | - Berkay Çağdaş
- Ankara Bilkent City Hospital, Department of Nuclear Medicine, Ankara, Turkey
| | - Mustafa Serdengeçti
- Ankara Bilkent City Hospital, Department of Nuclear Medicine, Ankara, Turkey
| | - Engin Alagöz
- Gulhane Training and Research Hospital, Department of Nuclear Medicine, Ankara, Turkey
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Lall R, Lee K, Chopra S, Kandala A, Evans M, Seo Y, Niknejad A, Anwar M. Low cost, high temporal resolution optical fiber-based γ-photon sensor for real-time pre-clinical evaluation of cancer-targeting radiopharmaceuticals. Biosens Bioelectron 2024; 247:115956. [PMID: 38145595 DOI: 10.1016/j.bios.2023.115956] [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: 10/06/2023] [Revised: 12/17/2023] [Accepted: 12/20/2023] [Indexed: 12/27/2023]
Abstract
Cancer radiopharmaceutical therapies (RPTs) have demonstrated great promise in the treatment of neuroendocrine and prostate cancer, giving hope to late-stage metastatic cancer patients with currently very few treatment options. These therapies have sparked a large amount of interest in pre-clinical research due to their ability to target metastatic disease, with many research efforts focused towards developing and evaluating targeted RPTs for different cancer types in in vivo models. Here we describe a method for monitoring real-time in vivo binding kinetics for the pre-clinical evaluation of cancer RPTs. Recognizing the significant heterogeneity in biodistribution of RPTs among even genetically identical animal models, this approach offers long-term monitoring of the same in vivo organism without euthanasia in contrast to ex vivo tissue dosimetry, while providing high temporal resolution with a low-cost, easily assembled platform, that is not present in small-animal SPECT/CTs. The method utilizes the developed optical fiber-based γ-photon biosensor, characterized to have a wide linear dynamic range with Lutetium-177 (177Lu) activity (0.5-500 μCi/mL), a common radioisotope used in cancer RPT. The probe's ability to track in vivo uptake relative to SPECT/CT and ex vivo dosimetry techniques was verified by administering 177Lu-PSMA-617 to mouse models bearing human prostate cancer tumors (PC3-PIP, PC3-flu). With this method for monitoring RPT uptake, it is possible to evaluate changes in tissue uptake at temporal resolutions <1 min to determine RPT biodistribution in pre-clinical models and better understand dose relationships with tumor ablation, toxicity, and recurrence when attempting to move therapies towards clinical trial validation.
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Affiliation(s)
- Rahul Lall
- Department of Electrical Engineering and Computer Science, University of California, Berkeley, Berkeley, CA, 94720, USA.
| | - Kyoungtae Lee
- Department of Radiation Oncology, University of California, San Francisco, San Francisco, CA, 94107, USA
| | - Shalini Chopra
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, CA, 94107, USA
| | - Averal Kandala
- Department of Electrical Engineering and Computer Science, University of California, Berkeley, Berkeley, CA, 94720, USA
| | - Michael Evans
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, CA, 94107, USA
| | - Youngho Seo
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, CA, 94107, USA
| | - Ali Niknejad
- Department of Electrical Engineering and Computer Science, University of California, Berkeley, Berkeley, CA, 94720, USA
| | - Mekhail Anwar
- Department of Electrical Engineering and Computer Science, University of California, Berkeley, Berkeley, CA, 94720, USA; Department of Radiation Oncology, University of California, San Francisco, San Francisco, CA, 94107, USA
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Radzina M, Saule L, Mamis E, Koester U, Cocolios TE, Pajuste E, Kalnina M, Palskis K, Sawitzki Z, Talip Z, Jensen M, Duchemin C, Leufgen K, Stora T. Novel radionuclides for use in Nuclear Medicine in Europe: where do we stand and where do we go? EJNMMI Radiopharm Chem 2023; 8:27. [PMID: 37823964 PMCID: PMC10570248 DOI: 10.1186/s41181-023-00211-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Accepted: 09/28/2023] [Indexed: 10/13/2023] Open
Abstract
BACKGROUND In order to support the ongoing research across Europe to facilitate access to novel radionuclides, the PRISMAP consortium (European medical radionuclides programme) was established to offer the broadest catalog of non-conventional radionuclides for medical and translational research. The aim of this article is to introduce readers with current status of novel radionuclides in Europe. MAIN BODY A consortium questionnaire was disseminated through the PRISMAP consortium and user community, professional associations and preclinical/clinical end users in Europe and the current status of clinical end-users in nuclear medicine were identified. A total of 40 preclinical/clinical users institutions took part in the survey. Clinical end users currently use the following radionuclides in their studies: 177Lu, 68 Ga, 111In, 90Y, other alpha emitters, 225Ac, 64Cu and Terbium isotopes. Radionuclides that would be of interest for users within the next 2-5 years are 64Cu, Terbium radionuclide "family" and alpha emitters, such as 225Ac. CONCLUSIONS Thanks to a questionnaire distributed by the PRISMAP consortium, the current status and needs of clinical end-users in nuclear medicine were identified.
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Affiliation(s)
- Maija Radzina
- University of Latvia, Riga, Latvia
- CERN, Geneva, Switzerland
- Riga Stradins University, Riga, Latvia
| | - Laura Saule
- University of Latvia, Riga, Latvia.
- Riga Stradins University, Riga, Latvia.
| | - Edgars Mamis
- University of Latvia, Riga, Latvia
- CERN, Geneva, Switzerland
| | | | | | | | | | - Kristaps Palskis
- CERN, Geneva, Switzerland
- Riga Technical University, Riga, Latvia
| | | | - Zeynep Talip
- Paul Scherrer Institute (PSI), Villigen, Switzerland
| | - Mikael Jensen
- Technical University of Denmark, Kongens Lyngby, Denmark
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He H, Li K, Li H, Zhu S, Qin S, Mao Y, Lin J, Qiu L, Yu C. Development of a multifunctional platform for near-infrared imaging and targeted radionuclide therapy for tumors. Eur J Pharm Biopharm 2023; 185:107-115. [PMID: 36858246 DOI: 10.1016/j.ejpb.2023.02.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Revised: 01/27/2023] [Accepted: 02/21/2023] [Indexed: 03/03/2023]
Abstract
Biotin receptor (BR) is overexpressed in several human tumor cell lines and has become an important biomarker for tumor diagnosis and treatment. Therefore, much attention has been attracted in the field of developing BR-targeting agents. In clinical practice, a multifunctional platform that can be used for both diagnosis and treatment is much desirable. In this study, to improve diagnostic and therapeutic efficacy of BR-positive tumors, we developed a multifunctional platform RT-H2 to combine with the cyanine scaffold for near infrared (NIR) imaging and the radioisotope 131I for targeted radionuclide therapy (TRT). In vitro experiments showed that RT-H2 possessed favorable NIR properties and could selectively accumulate in BR-positive HeLa cells. In vivo NIR imaging of HeLa tumor-bearing mice exhibited high accumulation and long retention time (72 h) of RT-H2 in the tumor. Furthermore, RT-H2 was also employed as a carrier to develop 131I-labeled TRT agent due to its favorable properties in vivo. The radiolabeling conditions were optimized and the optimal conditions determined to be 1.2 equiv of Idogen, reaction time 4 min and room temperature, yielding the radiotracer [131I]I-RT-H2 with the radiochemical purity (RCP) of > 95% after a simple purification by a C18 column. In vitro cell experiments indicated that [131I]I-RT-H2 could specifically target Hela cells and displayed dose-dependent antitumor effect. In vivo experiments demonstrated that [131I]I-RT-H2 obviously inhibited the tumor proliferation in HeLa tumor-bearing mice within 4 weeks. All these results indicate that RT-H2 has the potential to serve as a multifunctional platform for tumor diagnosis and treatment.
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Affiliation(s)
- Huihui He
- NHC Key Laboratory of Nuclear Medicine, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063, China; Department of Nuclear Medicine, Affiliated Hospital of Jiangnan University, Wuxi 214000, China
| | - Ke Li
- NHC Key Laboratory of Nuclear Medicine, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063, China
| | - Hang Li
- NHC Key Laboratory of Nuclear Medicine, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063, China
| | - Shiliang Zhu
- NHC Key Laboratory of Nuclear Medicine, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063, China
| | - Shuai Qin
- NHC Key Laboratory of Nuclear Medicine, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063, China
| | - Yong Mao
- Department of Nuclear Medicine, Affiliated Hospital of Jiangnan University, Wuxi 214000, China
| | - Jianguo Lin
- NHC Key Laboratory of Nuclear Medicine, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063, China
| | - Ling Qiu
- NHC Key Laboratory of Nuclear Medicine, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063, China.
| | - Chunjing Yu
- Department of Nuclear Medicine, Affiliated Hospital of Jiangnan University, Wuxi 214000, China.
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Borbinha J, Ferreira P, Costa D, Vaz P, Di Maria S. Targeted radionuclide therapy directed to the tumor phenotypes: A dosimetric approach using MC simulations. Appl Radiat Isot 2023; 192:110569. [PMID: 36436229 DOI: 10.1016/j.apradiso.2022.110569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 11/07/2022] [Accepted: 11/16/2022] [Indexed: 11/21/2022]
Abstract
BACKGROUND In Targeted Radionuclide Therapy (TRT), the continuous technological effort in imaging tumor phenotypes (i.e. sub-volumes with different phenotypic characteristics) and in precise radiopharmaceutical tumor-targeting, is allowing for a better dosimetric optimization at the tumor phenotype level. The aim of this study was to evaluate the dosimetric efficiency (considering strategic absorbed dose delivery to the phenotypes) of personalized TRT directed to the tumor phenotypes. METHODS The dosimetric assessment was performed using a four-phenotype realistic tumor model implemented within the ICRP reference voxel phantom and simulations using the state-of-the-art Monte Carlo program PENELOPE. The dose assessment was performed for five radionuclides commonly used in therapy and/or diagnostic procedures: 125I, 99mTc, 177Lu, 161Tb and 67Ga. Two irradiation scenarios were considered: (i) the Whole Tumor Treatment Planning Scenario (WTTPS), i.e. the four phenotypes irradiated with the same radionuclide; (ii) the Phenotype Treatment Planning Scenario (PTPS), i.e. each phenotype irradiated by a single radionuclide. The optimal radionuclide configurations were studied considering the maximization of the absorbed dose delivered to the tumor and the minimization of dose to healthy tissues. RESULTS In WTTPS, 125I outperforms the other radionuclides in terms of the ratio of the maximum absorbed dose delivered to the tumor and the minimum absorbed dose delivered to healthy tissues. In the PTPS, the use of 161Tb in combination with the other radionuclides maximizes the absorbed dose in the tumor tissues while simultaneously minimizing dose to healthy tissue, compared to the WTTPS. In agreement with recent pre-clinical studies, our computational results confirm and indicate the beneficial additive dosimetric effects of Auger and conversion electrons of 161Tb with respect to 177Lu, when considering the same cumulated activity for both. Interestingly, in considering a realistic tumor model, the better dosimetric performances of 161Tb were confirmed also for tumor volumes ranging from 1.98 cm3 to 33.32 cm3. CONCLUSIONS Dose assessment in realistic non-homogeneous tumor models could provide more insights with respect to consider only homogenous water-spheres tumor models and should be taken into account in dosimetry-based TRT planning studies.
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Affiliation(s)
- Jorge Borbinha
- Centro de Ciências e Tecnologias Nucleares - Instituto Superior Técnico, Universidade de Lisboa, Estrada Nacional 10, ao km 139,7, 2695-066, Bobadela, Portugal.
| | - Paulo Ferreira
- Champalimaud Centre for the Unknown, Fundação Champalimaud, Avenida Brasília, 1400-038, Lisboa, Portugal.
| | - Durval Costa
- Champalimaud Centre for the Unknown, Fundação Champalimaud, Avenida Brasília, 1400-038, Lisboa, Portugal.
| | - Pedro Vaz
- Centro de Ciências e Tecnologias Nucleares - Instituto Superior Técnico, Universidade de Lisboa, Estrada Nacional 10, ao km 139,7, 2695-066, Bobadela, Portugal.
| | - Salvatore Di Maria
- Centro de Ciências e Tecnologias Nucleares - Instituto Superior Técnico, Universidade de Lisboa, Estrada Nacional 10, ao km 139,7, 2695-066, Bobadela, Portugal.
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8
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Van B, Dewaraja YK, Niedbala JT, Rosebush G, Kazmierski M, Hubers D, Mikell JK, Wilderman SJ. Experimental validation of Monte Carlo dosimetry for therapeutic beta emitters with radiochromic film in a 3D-printed phantom. Med Phys 2023; 50:540-556. [PMID: 35983857 PMCID: PMC10019496 DOI: 10.1002/mp.15926] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Revised: 07/21/2022] [Accepted: 07/31/2022] [Indexed: 01/25/2023] Open
Abstract
PURPOSE Validation of dosimetry software, such as Monte Carlo (MC) radiation transport codes used for patient-specific absorbed dose estimation, is critical prior to their use in clinical decision making. However, direct experimental validation in the clinic is generally not performed for low/medium-energy beta emitters used in radiopharmaceutical therapy (RPT) due to the challenges of measuring energy deposited by short-range particles. Our objective was to design a practical phantom geometry for radiochromic film (RF)-based absorbed dose measurements of beta-emitting radionuclides and perform experiments to directly validate our in-house developed Dose Planning Method (DPM) MC code dedicated to internal dosimetry. METHODS The experimental setup was designed for measuring absorbed dose from beta emitters that have a range sufficiently penetrating to ∼200 μm in water as well as to capture any photon contributions to absorbed dose. Assayed 177 Lu and 90 Y liquid sources, 13-450 MBq estimated to deliver 0.5-10 Gy to the sensitive layer of the RF, were injected into the cavity of two 3D-printed half-cylinders that had been sealed with 12.7 μm or 25.4 μm thick Kapton Tape. A 3.8 × 6 cm strip of GafChromic EBT3 RF was sandwiched between the two taped half-cylinders. After 2-48 h exposures, films were retrieved and wipe tested for contamination. Absorbed dose to the RF was measured using a commercial triple-channel dosimetry optimization method and a calibration generated via 6 MV photon beam. Profiles were analyzed across the central 1 cm2 area of the RF for validation. Eleven experiments were completed with 177 Lu and nine with 90 Y both in saline and a bone equivalent solution. Depth dose curves were generated for 177 Lu and 90 Y stacking multiple RF strips between a single filled half-cylinder and an acrylic backing. All experiments were modeled in DPM to generate voxelized MC absorbed dose estimates. We extended our study to benchmark general purpose MC codes MCNP6 and EGSnrc against the experimental results as well. RESULTS A total of 20 experiments showed that both the 3D-printed phantoms and the final absorbed dose values were reproducible. The agreement between the absorbed dose estimates from the RF measurements and DPM was on average -4.0% (range -10.9% to 3.2%) for all single film 177 Lu experiments and was on average -1.0% (range -2.7% to 0.7%) for all single film 90 Y experiments. Absorbed depth dose estimates by DPM agreed with RF on average 1.2% (range -8.0% to 15.2%) across all depths for 177 Lu and on average 4.0% (range -5.0% to 9.3%) across all depths for 90 Y. DPM absorbed dose estimates agreed with estimates from EGSnrc and MCNP across the board, within 4.7% and within 3.4% for 177 Lu and 90 Y respectively, for all geometries and across all depths. MC showed that absorbed dose to RF from betas was greater than 92% of the total (betas + other radiations) for 177 Lu, indicating measurement of dominant beta contribution with our design. CONCLUSIONS The reproducible results with a RF insert in a simple phantom designed for liquid sources demonstrate that this is a reliable setup for experimentally validating dosimetry algorithms used in therapies with beta-emitting unsealed sources. Absorbed doses estimated with the DPM MC code showed close agreement with RF measurement and with results from two general purpose MC codes, thereby validating the use of this algorithms for clinical RPT dosimetry.
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Affiliation(s)
- Benjamin Van
- Department of Radiology, Michigan Medicine, Ann Arbor, Michigan, USA
| | - Yuni K Dewaraja
- Department of Radiology, Michigan Medicine, Ann Arbor, Michigan, USA
| | - Jeremy T Niedbala
- Department of Radiology, Michigan Medicine, Ann Arbor, Michigan, USA
| | - Gerrid Rosebush
- Department of Radiology, Michigan Medicine, Ann Arbor, Michigan, USA
| | | | - David Hubers
- Department of Radiology, Michigan Medicine, Ann Arbor, Michigan, USA
| | - Justin K Mikell
- Department of Radiation Oncology, Michigan Medicine, Ann Arbor, Michigan, USA.,Department of Radiation Oncology, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Scott J Wilderman
- Department of Nuclear Engineering and Radiologic Sciences, University of Michigan, Ann Arbor, Michigan, USA
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9
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Sun J, Huangfu Z, Yang J, Wang G, Hu K, Gao M, Zhong Z. Imaging-guided targeted radionuclide tumor therapy: From concept to clinical translation. Adv Drug Deliv Rev 2022; 190:114538. [PMID: 36162696 DOI: 10.1016/j.addr.2022.114538] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2022] [Revised: 09/03/2022] [Accepted: 09/11/2022] [Indexed: 01/24/2023]
Abstract
Since the first introduction of sodium iodide I-131 for use with thyroid patients almost 80 years ago, more than 50 radiopharmaceuticals have reached the markets for a wide range of diseases, especially cancers. The nuclear medicine paradigm also shifts from solely molecular imaging or radionuclide therapy to imaging-guided radionuclide therapy, which is deemed a vital component of precision cancer therapy and an emerging medical modality for personalized medicine. The imaging-guided radionuclide therapy highlights the systematic integration of targeted nuclear diagnostics and radionuclide therapeutics. Regarding this, nuclear imaging serves to "visualize" the lesions and guide the therapeutic strategy, followed by administration of a precise patient specific dose of radiotherapeutics for treatment according to the absorbed dose to different organs and tumors calculated by dosimetry tools, and finally repeated imaging to predict the prognosis. This strategy leads to significantly enhanced therapeutic efficacy, improved patient outcomes, and manageable adverse events. In this review, we provide an overview of imaging-guided targeted radionuclide therapy for different tumors such as advanced prostate cancer and neuroendocrine tumors, with a focus on development of new radioligands and their preclinical and clinical results, and further discuss about challenges and future perspectives.
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Affiliation(s)
- Juan Sun
- College of Pharmaceutical Sciences, and State Key Laboratory of Radiation Medicine and Protection, Soochow University, Suzhou 215123, People's Republic of China; Biomedical Polymers Laboratory, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, People's Republic of China
| | - Zhenyuan Huangfu
- College of Pharmaceutical Sciences, and State Key Laboratory of Radiation Medicine and Protection, Soochow University, Suzhou 215123, People's Republic of China; Biomedical Polymers Laboratory, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, People's Republic of China
| | - Jiangtao Yang
- College of Pharmaceutical Sciences, and State Key Laboratory of Radiation Medicine and Protection, Soochow University, Suzhou 215123, People's Republic of China; Biomedical Polymers Laboratory, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, People's Republic of China
| | - Guanglin Wang
- State Key Laboratory of Radiation Medicine and Protection, School of Radiation Medicine and Protection & School for Radiological and Interdisciplinary Sciences (RAD-X), Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Soochow University, Suzhou 215123, People's Republic of China.
| | - Kuan Hu
- Department of Advanced Nuclear Medicine Sciences, Institute for Quantum Medical Sciences, Quantum Life and Medical Science Directorate, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan.
| | - Mingyuan Gao
- State Key Laboratory of Radiation Medicine and Protection, School of Radiation Medicine and Protection & School for Radiological and Interdisciplinary Sciences (RAD-X), Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Soochow University, Suzhou 215123, People's Republic of China
| | - Zhiyuan Zhong
- College of Pharmaceutical Sciences, and State Key Laboratory of Radiation Medicine and Protection, Soochow University, Suzhou 215123, People's Republic of China; Biomedical Polymers Laboratory, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, People's Republic of China.
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10
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Radionuclide Delivery Strategies in Tumor Treatment: A Systematic Review. Curr Issues Mol Biol 2022; 44:3267-3282. [PMID: 35892711 PMCID: PMC9332578 DOI: 10.3390/cimb44080225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Revised: 07/14/2022] [Accepted: 07/19/2022] [Indexed: 11/17/2022] Open
Abstract
The aim of this review was to assess recent progress in targeted radionuclide tumor therapy, focusing on the best delivery strategies. A literature search was conducted in PubMed, Web of Science, and Scopus using the terms "radionuclides", "liposomes", "avidin-biotin interaction", "theranostic", and "molecular docking". The 10 year filter was applied, except for the avidin-biotin interaction. Data were retrieved from both preclinical and clinical settings. Three targeting strategies were considered: pretargeting, liposomes, and ligands. Pretargeting can be achieved by exploiting the avidin-biotin interaction. This strategy seems very promising, although it has been investigated mainly in resectable tumors. Radiolabeled liposomes have attracted new interest as probes to identify the most suitable patients for treatment with liposomal formulations of common chemotherapeutics. The use of ligands for the delivery of radiotherapeutics to a specific target is still the most appealing strategy for treating tumors. The most appropriate ligand can be identified by virtually simulating its interaction with the receptor. All strategies showed great potential for use in targeted radionuclide therapy, but they also have numerous drawbacks. The most promising option is probably the one based on the use of new ligands.
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11
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Ertveldt T, De Beck L, De Ridder K, Locy H, de Mey W, Goyvaerts C, Lecocq Q, Ceuppens H, De Vlaeminck Y, Awad RM, Keyaerts M, Devoogdt N, D'Huyvetter M, Breckpot K, Krasniqi A. Targeted Radionuclide Therapy with Low and High-Dose Lutetium-177-Labeled Single Domain Antibodies Induces Distinct Immune Signatures in a Mouse Melanoma Model. Mol Cancer Ther 2022; 21:1136-1148. [PMID: 35499391 PMCID: PMC9377759 DOI: 10.1158/1535-7163.mct-21-0791] [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: 10/03/2021] [Revised: 02/16/2022] [Accepted: 04/22/2022] [Indexed: 01/07/2023]
Abstract
Targeted radionuclide therapy (TRT) using probes labeled with Lutetium-177 (177Lu) represents a new and growing type of cancer therapy. We studied immunologic changes in response to TRT with 177Lu labeled anti-human CD20 camelid single domain antibodies (sdAb) in a B16-melanoma model transfected to express human CD20, the target antigen, and ovalbumin, a surrogate tumor antigen. High-dose TRT induced melanoma cell death, calreticulin exposure, and ATP-release in vitro. Melanoma-bearing mice received fractionated low and high-dose TRT via tumor targeting anti-human CD20 sdAbs, as opposed to control sdAbs. Tumor growth was delayed with both doses. Low- and high-dose TRT increased IL10 serum levels. Low-dose TRT also decreased CCL5 serum levels. At the tumor, high-dose TRT induced a type I IFN gene signature, while low-dose TRT induced a proinflammatory gene signature. Low- and high-dose TRT increased the percentage of PD-L1pos and PD-L2pos myeloid cells in tumors with a marked increase in alternatively activated macrophages after high-dose TRT. The percentage of tumor-infiltrating T cells was not changed, yet a modest increase in ovalbumin-specific CD8pos T-cells was observed after low-dose TRT. Contradictory, low and high-dose TRT decreased CD4pos Th1 cells in addition to double negative T cells. In conclusion, these data suggest that low and high-dose TRT induce distinct immunologic changes, which might serve as an anchoring point for combination therapy.
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Affiliation(s)
- Thomas Ertveldt
- Laboratory for Molecular and Cellular Therapy, Department of Biomedical Sciences, Vrije Universiteit Brussel, Brussels, Belgium.,Corresponding Authors: Karine Breckpot, Laboratory for Molecular and Cellular Therapy, Department of Biomedical Sciences, Vrije Universiteit Brussel, Laarbeeklaan 103, Brussels 1090, Belgium. Phone: 322-477-4566; Fax: 322-477-4506; E-mail: ; and Thomas Ertveldt, E-mail:
| | - Lien De Beck
- Laboratory for Molecular and Cellular Therapy, Department of Biomedical Sciences, Vrije Universiteit Brussel, Brussels, Belgium
| | - Kirsten De Ridder
- Laboratory for Molecular and Cellular Therapy, Department of Biomedical Sciences, Vrije Universiteit Brussel, Brussels, Belgium
| | - Hanne Locy
- Laboratory for Molecular and Cellular Therapy, Department of Biomedical Sciences, Vrije Universiteit Brussel, Brussels, Belgium
| | - Wout de Mey
- Laboratory for Molecular and Cellular Therapy, Department of Biomedical Sciences, Vrije Universiteit Brussel, Brussels, Belgium
| | - Cleo Goyvaerts
- Laboratory for Molecular and Cellular Therapy, Department of Biomedical Sciences, Vrije Universiteit Brussel, Brussels, Belgium
| | - Quentin Lecocq
- Laboratory for Molecular and Cellular Therapy, Department of Biomedical Sciences, Vrije Universiteit Brussel, Brussels, Belgium
| | - Hannelore Ceuppens
- Laboratory for Molecular and Cellular Therapy, Department of Biomedical Sciences, Vrije Universiteit Brussel, Brussels, Belgium
| | - Yannick De Vlaeminck
- Laboratory for Molecular and Cellular Therapy, Department of Biomedical Sciences, Vrije Universiteit Brussel, Brussels, Belgium
| | - Robin Maximilian Awad
- Laboratory for Molecular and Cellular Therapy, Department of Biomedical Sciences, Vrije Universiteit Brussel, Brussels, Belgium
| | - Marleen Keyaerts
- Laboratory for In Vivo Cellular and Molecular Imaging, Department of Medical Imaging, Vrije Universiteit Brussel, Brussels, Belgium.,Department of Nuclear Medicine, UZ Brussel, Vrije Universiteit Brussel, Brussels, Belgium
| | - Nick Devoogdt
- Laboratory for In Vivo Cellular and Molecular Imaging, Department of Medical Imaging, Vrije Universiteit Brussel, Brussels, Belgium
| | - Matthias D'Huyvetter
- Laboratory for In Vivo Cellular and Molecular Imaging, Department of Medical Imaging, Vrije Universiteit Brussel, Brussels, Belgium
| | - Karine Breckpot
- Laboratory for Molecular and Cellular Therapy, Department of Biomedical Sciences, Vrije Universiteit Brussel, Brussels, Belgium.,Corresponding Authors: Karine Breckpot, Laboratory for Molecular and Cellular Therapy, Department of Biomedical Sciences, Vrije Universiteit Brussel, Laarbeeklaan 103, Brussels 1090, Belgium. Phone: 322-477-4566; Fax: 322-477-4506; E-mail: ; and Thomas Ertveldt, E-mail:
| | - Ahmet Krasniqi
- Laboratory for In Vivo Cellular and Molecular Imaging, Department of Medical Imaging, Vrije Universiteit Brussel, Brussels, Belgium
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12
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Xue A, Fan S. Matrices and Affinity Ligands for Antibody Purification and Corresponding Applications in Radiotherapy. Biomolecules 2022; 12:biom12060821. [PMID: 35740946 PMCID: PMC9221399 DOI: 10.3390/biom12060821] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 06/09/2022] [Accepted: 06/10/2022] [Indexed: 02/05/2023] Open
Abstract
Antibodies have become an important class of biological products in cancer treatments such as radiotherapy. The growing therapeutic applications have driven a demand for high-purity antibodies. Affinity chromatography with a high affinity and specificity has always been utilized to separate antibodies from complex mixtures. Quality chromatographic components (matrices and affinity ligands) have either been found or generated to increase the purity and yield of antibodies. More importantly, some matrices (mainly particles) and affinity ligands (including design protocols) for antibody purification can act as radiosensitizers or carriers for therapeutic radionuclides (or for radiosensitizers) either directly or indirectly to improve the therapeutic efficiency of radiotherapy. This paper provides a brief overview on the matrices and ligands used in affinity chromatography that are involved in antibody purification and emphasizes their applications in radiotherapy to enrich potential approaches for improving the efficacy of radiotherapy.
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13
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Şan H. Youtube videos for the most commonly applied radionuclide treatments: sufficient for patients as an information source? Nucl Med Commun 2022; 43:656-662. [PMID: 35323148 DOI: 10.1097/mnm.0000000000001551] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVES YouTube is one of the most popular online sources of information for patients. The purpose of the study is to analyze the quality of YouTube videos about the most commonly applied radionuclide treatments. METHOD Related radionuclide therapy videos were searched on YouTube in October 2021. The quality of the videos was assessed by using the Journal of the American Medical Association (JAMA) benchmark criteria, the DISCERN Scale and the Global Quality Scale (GQS). RESULTS A total of 473 videos were assessed and 270 were included in the study according to inclusion and exclusion criteria. According to the GQS score, videos were categorized as high-quality (n:63, 23.33%), intermediate quality (n:118, 43.70%) and low-quality (n:89, 32.96 %) groups. The findings of our study showed that the highest number of video views and comments were in the low-quality group. In addition; the number of video likes, views and comments were the lowest in the high-quality video group. The most viewed and commented as well as most liked videos and the videos of highest video power index scores were nonphysician sourced videos. The most quality videos were the physician-sourced videos in terms of JAMA, DISCERN and GQS scores. CONCLUSION Although high-quality videos about radionuclide treatments on YouTube may enlighten and motivate patients positively; it should be kept in mind that improper information may also be uploaded to this platform. Under the guidance of the European Association of Nuclear Medicine, it is necessary to generate an official video in English with multilingual subtitles.
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Affiliation(s)
- Hüseyin Şan
- Ankara City Hospital, Department of Nuclear Medicine, Ankara, Turkey
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14
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Lakiza O, Lutze J, Vogle A, Williams J, Abukdheir A, Miller P, Liao CY'A, Pitroda SP, Martinez C, Olivas A, Setia N, Kron SJ, Weichselbaum RR, Keutgen XM. Loss of MEN1 function impairs DNA repair capability of pancreatic neuroendocrine tumors. Endocr Relat Cancer 2022; 29:225-239. [PMID: 35171113 PMCID: PMC9045673 DOI: 10.1530/erc-21-0247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Accepted: 02/16/2022] [Indexed: 11/08/2022]
Abstract
Somatic MEN1 mutations occur in up to 50% of pancreatic neuroendocrine tumors (PanNETs). Clinical studies have shown that radiation therapy (IR) is effective in a subset of PanNETs, but it remains unclear why some patients respond better to IR than others. Herein, we study whether MEN1 loss of function increases radiosensitivity of PanNETs and determine its effect on DNA double-strand break (DSB) repair. After creating a MEN1 knockout PanNET cell line, we confirmed reduced DSB repair capacity in MEN1-deficient cells and linked these findings to a defect in homologous recombination, as well as reduced BRCA2 expression levels. Consistent with this model, we found that MEN1 mutant cells displayed increased sensitivity to the highly trapping poly (ADP-ribose) polymerase (PARP) 1 inhibitor talazoparib in vitro. Our results suggest that combining IR with PARP inhibition may be beneficial in patients with PanNETs and MEN1 loss of function.
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Affiliation(s)
- Olga Lakiza
- Endocrine and Neuroendocrine Surgery Research Program, Division of General Surgery and Surgical Oncology, Department of Surgery, University of Chicago Medicine, Chicago, Illinois, USA
| | - Julian Lutze
- Committee on Cancer Biology, University of Chicago, Chicago, Illinois, USA
| | - Alyx Vogle
- Endocrine and Neuroendocrine Surgery Research Program, Division of General Surgery and Surgical Oncology, Department of Surgery, University of Chicago Medicine, Chicago, Illinois, USA
| | - Jelani Williams
- Endocrine and Neuroendocrine Surgery Research Program, Division of General Surgery and Surgical Oncology, Department of Surgery, University of Chicago Medicine, Chicago, Illinois, USA
| | - Abde Abukdheir
- Division of Hematology, Oncology, and Cell Therapy, Department of Internal Medicine, Rush University Medical Center, Chicago, Illinois, USA
| | - Paul Miller
- Endocrine and Neuroendocrine Surgery Research Program, Division of General Surgery and Surgical Oncology, Department of Surgery, University of Chicago Medicine, Chicago, Illinois, USA
| | - Chih-Yi 'Andy' Liao
- Division of Hematology and Oncology, Department of Internal Medicine, University of Chicago, Chicago, Illinois, USA
| | - Sean P Pitroda
- Department of Radiation Oncology and Cellular Biology, University of Chicago, Chicago, Illinois, USA
| | - Carlos Martinez
- Department of Radiation Oncology and Cellular Biology, University of Chicago, Chicago, Illinois, USA
| | - Andrea Olivas
- Department of Pathology, University of Chicago, Chicago, Illinois, USA
| | - Namrata Setia
- Department of Pathology, University of Chicago, Chicago, Illinois, USA
| | - Stephen J Kron
- Committee on Cancer Biology, University of Chicago, Chicago, Illinois, USA
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, Illinois, USA
| | - Ralph R Weichselbaum
- Department of Radiation Oncology and Cellular Biology, University of Chicago, Chicago, Illinois, USA
- Ludwig Center for Metastasis Research, University of Chicago, Chicago, Illinois, USA
| | - Xavier M Keutgen
- Endocrine and Neuroendocrine Surgery Research Program, Division of General Surgery and Surgical Oncology, Department of Surgery, University of Chicago Medicine, Chicago, Illinois, USA
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15
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Benešová M, Guzik P, Deberle LM, Busslinger SD, Landolt T, Schibli R, Müller C. Design and Evaluation of Novel Albumin-Binding Folate Radioconjugates: Systematic Approach of Varying the Linker Entities. Mol Pharm 2022; 19:963-973. [PMID: 35192367 DOI: 10.1021/acs.molpharmaceut.1c00932] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Tumor targeting using folate radioconjugates is a promising strategy for theragnostics of folate receptor-positive tumors. The aim of this study was to investigate the impact of structural modifications of folate radioconjugates on their pharmacokinetic properties. Four novel folate radioconjugates ([177Lu]Lu-OxFol-2, [177Lu]Lu-OxFol-3, [177Lu]Lu-OxFol-4, and [177Lu]Lu-OxFol-5), modified with a lipophilic or hydrophilic linker entity in close proximity to the albumin-binding 4-(p-iodophenyl)butanoate entity or the DOTA chelator, respectively, were designed and evaluated for comparison with the previously developed [177Lu]Lu-OxFol-1. A hydrophobic 4-(aminomethyl)benzoic acid linker, incorporated in close proximity to the 4-(p-iodophenyl)butanoate entity, enhanced the albumin-binding properties (relative affinity 7.3) of [177Lu]Lu-OxFol-3 as compared to those of [177Lu]Lu-OxFol-1 (relative affinity set as 1.0). On the other hand, a hydrophilic d-glutamic acid (d-Glu) linker entity used in [177Lu]Lu-OxFol-2 compromised the albumin-binding properties. [177Lu]Lu-OxFol-4 and [177Lu]Lu-OxFol-5, in which the respective linker entities were incorporated adjacent to the DOTA chelator, showed similar albumin-binding properties (0.6 and 1.0, respectively) as [177Lu]Lu-OxFol-1. Biodistribution studies in KB tumor-bearing nude mice revealed twofold higher tumor-to-kidney ratios at 4 h and 24 h after injection of [177Lu]Lu-OxFol-3 (∼1.2) than after injection of [177Lu]Lu-OxFol-1 (∼0.6). The tumor-to-kidney ratios of [177Lu]Lu-OxFol-2 were, however, much lower (∼0.2) due to the high kidney retention of this radioconjugate. The tumor-to-kidney ratios of [177Lu]Lu-OxFol-5 were only slightly increased (∼0.9), and the ratios for [177Lu]Lu-OxFol-4 (∼0.7) were in the same range as for [177Lu]Lu-OxFol-1. SPECT/CT imaging studies demonstrated similar tumor uptake of all radioconjugates but a clearly improved tumor-to-kidney ratio for [177Lu]Lu-OxFol-3 as compared to that for [177Lu]Lu-OxFol-1. Based on these data, it can be concluded that the linker entity in close proximity to the 4-(p-iodophenyl)butanoate entity affects the radioconjugate's pharmacokinetic profile considerably due to the altered affinity to albumin. Changes in the linker entity, which connects the DOTA chelator with the folate molecule, do not have a major impact on the radioconjugate's tissue distribution profile, however. As a result of these findings, [177Lu]Lu-OxFol-3 had a comparable therapeutic effect to that of [177Lu]Lu-OxFol-1 but appeared advantageous in preventing kidney damage. Provided that the kidneys will present the dose-limiting organs in patients, [177Lu]Lu-OxFol-3 would be the preferred candidate for a clinical translation.
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Affiliation(s)
- Martina Benešová
- Center for Radiopharmaceutical Sciences ETH-PSI-USZ, Paul Scherrer Institute, 5232 Villigen-PSI, Switzerland.,Department of Chemistry and Applied Biosciences, ETH Zurich, Vladimir-Prelog-Weg 1-5/10, 8093 Zurich, Switzerland
| | - Patrycja Guzik
- Center for Radiopharmaceutical Sciences ETH-PSI-USZ, Paul Scherrer Institute, 5232 Villigen-PSI, Switzerland
| | - Luisa M Deberle
- Center for Radiopharmaceutical Sciences ETH-PSI-USZ, Paul Scherrer Institute, 5232 Villigen-PSI, Switzerland
| | - Sarah D Busslinger
- Center for Radiopharmaceutical Sciences ETH-PSI-USZ, Paul Scherrer Institute, 5232 Villigen-PSI, Switzerland
| | - Tanja Landolt
- Center for Radiopharmaceutical Sciences ETH-PSI-USZ, Paul Scherrer Institute, 5232 Villigen-PSI, Switzerland
| | - Roger Schibli
- Center for Radiopharmaceutical Sciences ETH-PSI-USZ, Paul Scherrer Institute, 5232 Villigen-PSI, Switzerland.,Department of Chemistry and Applied Biosciences, ETH Zurich, Vladimir-Prelog-Weg 1-5/10, 8093 Zurich, Switzerland
| | - Cristina Müller
- Center for Radiopharmaceutical Sciences ETH-PSI-USZ, Paul Scherrer Institute, 5232 Villigen-PSI, Switzerland.,Department of Chemistry and Applied Biosciences, ETH Zurich, Vladimir-Prelog-Weg 1-5/10, 8093 Zurich, Switzerland
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16
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Müller C, Schibli R, Bernhardt P, Köster U, van der Meulen NP. Terbium radionuclides for theranostics. Nucl Med Mol Imaging 2022. [DOI: 10.1016/b978-0-12-822960-6.00076-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
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17
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Wang Q, Lu C, Li K, Xia YM, qiu L, Lin J. Legumain-mediated self-assembly of 131I-labelled agent for targeted radiotherapy of tumor. J Mater Chem B 2022; 10:2251-2259. [DOI: 10.1039/d1tb02862f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Targeted radionuclide therapy (TRT) has been a promising strategy for cancer therapy, which can inhibit or kill cancer cells by selectively delivering radionuclide to target tissues. Herein, a legumain-targeted therapeutic...
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18
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Compensating Positron Range Effects of Ga-68 in Preclinical PET Imaging by Using Convolutional Neural Network: A Monte Carlo Simulation Study. Diagnostics (Basel) 2021; 11:diagnostics11122275. [PMID: 34943511 PMCID: PMC8700176 DOI: 10.3390/diagnostics11122275] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 11/11/2021] [Accepted: 12/01/2021] [Indexed: 11/17/2022] Open
Abstract
This study aimed to investigate the feasibility of positron range correction based on three different convolutional neural network (CNN) models in preclinical PET imaging of Ga-68. The first model (CNN1) was originally designed for super-resolution recovery, while the second model (CNN2) and the third model (CNN3) were originally designed for pseudo CT synthesis from MRI. A preclinical PET scanner and 30 phantom configurations were modeled in Monte Carlo simulations, where each phantom configuration was simulated twice, once for Ga-68 (CNN input images) and once for back-to-back 511-keV gamma rays (CNN output images) with a 20 min emission scan duration. The Euclidean distance was used as the loss function to minimize the difference between CNN input and output images. According to our results, CNN3 outperformed CNN1 and CNN2 qualitatively and quantitatively. With regard to qualitative observation, it was found that boundaries in Ga-68 images became sharper after correction. As for quantitative analysis, the recovery coefficient (RC) and spill-over ratio (SOR) were increased after correction, while no substantial increase in coefficient of variation of RC (CVRC) or coefficient of variation of SOR (CVSOR) was observed. Overall, CNN3 should be a good candidate architecture for positron range correction in Ga-68 preclinical PET imaging.
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19
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Bolcaen J, Kleynhans J, Nair S, Verhoeven J, Goethals I, Sathekge M, Vandevoorde C, Ebenhan T. A perspective on the radiopharmaceutical requirements for imaging and therapy of glioblastoma. Theranostics 2021; 11:7911-7947. [PMID: 34335972 PMCID: PMC8315062 DOI: 10.7150/thno.56639] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Accepted: 03/29/2021] [Indexed: 11/26/2022] Open
Abstract
Despite numerous clinical trials and pre-clinical developments, the treatment of glioblastoma (GB) remains a challenge. The current survival rate of GB averages one year, even with an optimal standard of care. However, the future promises efficient patient-tailored treatments, including targeted radionuclide therapy (TRT). Advances in radiopharmaceutical development have unlocked the possibility to assess disease at the molecular level allowing individual diagnosis. This leads to the possibility of choosing a tailored, targeted approach for therapeutic modalities. Therapeutic modalities based on radiopharmaceuticals are an exciting development with great potential to promote a personalised approach to medicine. However, an effective targeted radionuclide therapy (TRT) for the treatment of GB entails caveats and requisites. This review provides an overview of existing nuclear imaging and TRT strategies for GB. A critical discussion of the optimal characteristics for new GB targeting therapeutic radiopharmaceuticals and clinical indications are provided. Considerations for target selection are discussed, i.e. specific presence of the target, expression level and pharmacological access to the target, with particular attention to blood-brain barrier crossing. An overview of the most promising radionuclides is given along with a validation of the relevant radiopharmaceuticals and theranostic agents (based on small molecules, peptides and monoclonal antibodies). Moreover, toxicity issues and safety pharmacology aspects will be presented, both in general and for the brain in particular.
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Affiliation(s)
- Julie Bolcaen
- Radiobiology, Radiation Biophysics Division, Nuclear Medicine Department, iThemba LABS, Cape Town, South Africa
| | - Janke Kleynhans
- Nuclear Medicine Research Infrastructure NPC, Pretoria, South Africa
- Nuclear Medicine Department, University of Pretoria and Steve Biko Academic Hospital, Pretoria, South Africa
| | - Shankari Nair
- Radiobiology, Radiation Biophysics Division, Nuclear Medicine Department, iThemba LABS, Cape Town, South Africa
| | | | - Ingeborg Goethals
- Ghent University Hospital, Department of Nuclear Medicine, Ghent, Belgium
| | - Mike Sathekge
- Nuclear Medicine Research Infrastructure NPC, Pretoria, South Africa
- Nuclear Medicine Department, University of Pretoria and Steve Biko Academic Hospital, Pretoria, South Africa
| | - Charlot Vandevoorde
- Radiobiology, Radiation Biophysics Division, Nuclear Medicine Department, iThemba LABS, Cape Town, South Africa
| | - Thomas Ebenhan
- Nuclear Medicine Research Infrastructure NPC, Pretoria, South Africa
- Nuclear Medicine Department, University of Pretoria, Pretoria, South Africa
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20
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Chhabra A, Shukla J, Sharma U, Vatsa R, Bhatia A, Upadhyay D, Mittal BR. Re-188-tricarbonyl tamoxifen as a theranostic radiopharmaceutical for estrogen receptor expressing breast cancers: radiolabeling, characterization and in-vitro cytotoxic assessment. Nucl Med Commun 2021; 42:738-746. [PMID: 33741857 DOI: 10.1097/mnm.0000000000001402] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE Development of a novel theranostic radiopharmaceutical for estrogen receptor, expressing unresectable primary and metastatic breast cancers. METHODS Tamoxifen was radiolabeled with Rhenium-188 (Re-188) through tricarbonyl core. Radiolabeled complex was characterized by 1proton nuclear magnetic resonance spectroscopy and Matrix-assisted laser desorption ionization-time of flight (MALDI-TOF). Various quality control tests such as sterility, apyrogenicity, and radiochemical purity (RCP) were performed to assess the suitability of the radiopharmaceutical for intravenous administration. In-vitro cell culture studies were performed for cytotoxic assessment. In addition to this, exposure due to different doses of Re-188-tricarbonyl tamoxifen was also calculated. RESULTS Re-188-tricarbonyl and Re-188-tricarbonyl tamoxifen showed more than 99% RCP. Sample was found to be sterile and pyrogens levels were within the permissible limit. Re-188-tricarbonyl tamoxifen was successfully characterized by MALDI-TOF and 1H-NMR spectroscopy. Re-188 (1.480 MBq) and tamoxifen (0.027 or 0.054 µM) individually showed 36 and 70% cell death, respectively. However, radiolabeled complex (Re-188-tricarbonyl tamoxifen) with the same amount of radioactivity (1.480 MBq) increased the cell death to more than 90% with one-fifth to one-tenth molar concentration of tamoxifen (0.0054 μM). CONCLUSION Re-188-tricarbonyl tamoxifen can be synthesized in-house in radiopharmacy lab. Radionuclide therapy with Re-188-tricarbonyl tamoxifen can be given using 10 times less amount of tamoxifen as compared to cold tamoxifen.
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Affiliation(s)
- Anupriya Chhabra
- Department of Nuclear Medicine, Post Graduate Institute of Medical Education and Research, Chandigarh
| | - Jaya Shukla
- Department of Nuclear Medicine, Post Graduate Institute of Medical Education and Research, Chandigarh
| | - Uma Sharma
- Department of NMR and MRI, All India Institute of Medical Science, Delhi
| | - Rakhee Vatsa
- Department of Nuclear Medicine, Post Graduate Institute of Medical Education and Research, Chandigarh
| | - Alka Bhatia
- Department of Experimental Medicine and Biotechnology, Post Graduate Institute of Medical Education and Research, Chandigarh, India
| | - Deepti Upadhyay
- Department of NMR and MRI, All India Institute of Medical Science, Delhi
| | - Bhagwant Rai Mittal
- Department of Nuclear Medicine, Post Graduate Institute of Medical Education and Research, Chandigarh
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21
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Costa IM, Cheng J, Osytek KM, Imberti C, Terry SYA. Methods and techniques for in vitro subcellular localization of radiopharmaceuticals and radionuclides. Nucl Med Biol 2021; 98-99:18-29. [PMID: 33964707 PMCID: PMC7610823 DOI: 10.1016/j.nucmedbio.2021.03.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 03/18/2021] [Accepted: 03/30/2021] [Indexed: 12/28/2022]
Abstract
In oncology, the holy grail of radiotherapy is specific radiation dose deposition in tumours with minimal healthy tissue toxicity. If used appropriately, injectable, systemic radionuclide therapies could meet these criteria, even for treatment of micrometastases and single circulating tumour cells. The clinical use of α and β- particle-emitting molecular radionuclide therapies is rising, however clinical translation of Auger electron-emitting radionuclides is hampered by uncertainty around their exact subcellular localisation, which in turn affects the accuracy of dosimetry. This review aims to discuss and compare the advantages and disadvantages of various subcellular localisation methods available to localise radiopharmaceuticals and radionuclides for in vitro investigations.
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Affiliation(s)
- Ines M Costa
- Department of Imaging Chemistry and Biology, School of Biomedical Engineering and Imaging Sciences, King's College London, London SE1 7EH, United Kingdom
| | - Jordan Cheng
- Department of Imaging Chemistry and Biology, School of Biomedical Engineering and Imaging Sciences, King's College London, London SE1 7EH, United Kingdom
| | - Katarzyna M Osytek
- Department of Imaging Chemistry and Biology, School of Biomedical Engineering and Imaging Sciences, King's College London, London SE1 7EH, United Kingdom
| | - Cinzia Imberti
- Department of Imaging Chemistry and Biology, School of Biomedical Engineering and Imaging Sciences, King's College London, London SE1 7EH, United Kingdom; Department of Chemistry, University of Warwick, Coventry CV4 7AL, UK
| | - Samantha Y A Terry
- Department of Imaging Chemistry and Biology, School of Biomedical Engineering and Imaging Sciences, King's College London, London SE1 7EH, United Kingdom.
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Suman SK, Subramanian S, Mukherjee A. Combination radionuclide therapy: A new paradigm. Nucl Med Biol 2021; 98-99:40-58. [PMID: 34029984 DOI: 10.1016/j.nucmedbio.2021.05.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2020] [Revised: 04/23/2021] [Accepted: 05/06/2021] [Indexed: 12/15/2022]
Abstract
Targeted molecular radionuclide therapy (MRT) has shown its potential for the treatment of cancers of multiple origins. A combination therapy strategy employing two or more distinct therapeutic approaches in cancer management is aimed at circumventing tumor resistance by simultaneously targeting compensatory signaling pathways or bypassing survival selection mutations acquired in response to individual monotherapies. Combination radionuclide therapy (CRT) is a newer application of the concept, utilizing a combination of radiolabeled molecular targeting agents with chemotherapy and beam radiation therapy for enhanced therapeutic index. Encouraging results are reported with chemotherapeutic agents in combination with radiolabeled targeting molecules for cancer therapy. With increasing awareness of the various survival and stress response pathways activated after radionuclide therapy, different holistic combinations of MRT agents with radiosensitizers targeting such pathways have also been explored. MRT has also been studied in combination with beam radiotherapy modalities such as external beam radiation therapy and carbon ion radiation therapy to enhance the anti-tumor response. Nanotechnology aids in CRT by bringing together multiple monotherapies on a single nanostructure platform for treating cancers in a more precise or personalized way. CRT will be a key player in managing cancers if correctly tailored to the individual patient profile. The success of CRT lies in an in-depth understanding of the radiobiological principles and pathways activated in response.
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Affiliation(s)
- Shishu Kant Suman
- Radiopharmaceuticals Division, Bhabha Atomic Research Centre; Homi Bhabha National Institute, Mumbai 400094, India
| | - Suresh Subramanian
- Radiopharmaceuticals Division, Bhabha Atomic Research Centre; Homi Bhabha National Institute, Mumbai 400094, India
| | - Archana Mukherjee
- Radiopharmaceuticals Division, Bhabha Atomic Research Centre; Homi Bhabha National Institute, Mumbai 400094, India.
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23
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Radiotherapy enhances uptake and efficacy of 90Y-cetuximab: A preclinical trial. Radiother Oncol 2021; 155:285-292. [DOI: 10.1016/j.radonc.2020.11.013] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 11/09/2020] [Accepted: 11/13/2020] [Indexed: 01/09/2023]
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24
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Jin ZH, Tsuji AB, Degardin M, Sugyo A, Obara S, Wakizaka H, Nagatsu K, Hu K, Zhang MR, Dumy P, Boturyn D, Higashi T. Radiotheranostic Agent 64Cu-cyclam-RAFT-c(-RGDfK-) 4 for Management of Peritoneal Metastasis in Ovarian Cancer. Clin Cancer Res 2020; 26:6230-6241. [PMID: 32933998 DOI: 10.1158/1078-0432.ccr-20-1205] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 08/11/2020] [Accepted: 09/10/2020] [Indexed: 11/16/2022]
Abstract
PURPOSE Ovarian cancer peritoneal metastases (OCPMs) are a pathophysiologically heterogeneous group of tumors that are rarely curable. αVβ3 integrin (αVβ3) is overexpressed on tumoral neovessels and frequently on ovarian cancer cells. Here, using two clinically relevant αVβ3-positive OCPM mouse models, we studied the theranostic potential of an αVβ3-specific radiopeptide, 64Cu-cyclam-RAFT-c(-RGDfK-)4 (64Cu-RaftRGD), and its intra- and intertumoral distribution in relation to the tumor microenvironment. EXPERIMENTAL DESIGN αVβ3-expressing peritoneal and subcutaneous models of ovarian carcinoma (IGR-OV1 and NIH:OVCAR-3) were established in nude mice. 64Cu-RaftRGD was administered either intravenously or intraperitoneally. We performed intratumoral distribution (ITD) studies, PET/CT imaging and quantification, biodistribution assay and radiation dosimetry, and therapeutic efficacy and toxicity studies. RESULTS Intraperitoneal administration was an efficient route for targeting 64Cu-RaftRGD to OCPMs with excellent tumor penetration. Using the fluorescence surrogate, Cy5.5-RaftRGD, in our unique high-resolution multifluorescence analysis, we found that the ITD of 64Cu-RaftRGD was spatially distinct from, but complementary to, that of hypoxia. 64Cu-RaftRGD-based PET enabled clear visualization of multiple OCPM deposits and ascites and biodistribution analysis demonstrated an inverse correlation between tumor uptake and tumor size (1.2-17.2 mm). 64Cu-RaftRGD at a radiotherapeutic dose (148 MBq/0.357 nmol) showed antitumor activities by inhibiting tumor cell proliferation and inducing apoptosis, with negligible toxicity. CONCLUSIONS Collectively, these results demonstrate the all-in-one potential of 64Cu-RaftRGD for imaging guided radiotherapy of OCPM by targeting both tumoral neovessels and cancerous cells. On the basis of the ITD finding, we propose that pairing αVβ3- and hypoxia-targeted radiotherapies could improve therapeutic efficacy by overcoming the heterogeneity of ITD encountered with single-agent treatments.
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Affiliation(s)
- Zhao-Hui Jin
- National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan.
| | - Atsushi B Tsuji
- National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan.
| | | | - Aya Sugyo
- National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Satoshi Obara
- National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Hidekatsu Wakizaka
- National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Kotaro Nagatsu
- National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Kuan Hu
- National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Ming-Rong Zhang
- National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Pascal Dumy
- Institut des Biomolécules Max Mousseron, École Nationale Supérieure de Chimie de Montpellier, Université de Montpellier, Montpellier, France
| | | | - Tatsuya Higashi
- National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
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25
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Spine and Non-spine Bone Metastases - Current Controversies and Future Direction. Clin Oncol (R Coll Radiol) 2020; 32:728-744. [PMID: 32747153 DOI: 10.1016/j.clon.2020.07.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Revised: 05/21/2020] [Accepted: 07/10/2020] [Indexed: 02/06/2023]
Abstract
Bone is a common site of metastases in advanced cancers. The main symptom is pain, which increases morbidity and reduces quality of life. The treatment of bone metastases needs a multidisciplinary approach, with the main aim of relieving pain and improving quality of life. Apart from systemic anticancer therapy (hormonal therapy, chemotherapy or immunotherapy), there are several therapeutic options available to achieve palliation, including analgesics, surgery, local radiotherapy, bone-seeking radioisotopes and bone-modifying agents. Long-term use of non-steroidal analgesics and opiates is associated with significant side-effects, and tachyphylaxis. Radiotherapy is effective mainly in localised disease sites. Bone-targeting radionuclides are useful in patients with multiple metastatic lesions. Bone-modifying agents are beneficial in reducing skeletal-related events. This overview focuses on the role of surgery, including minimally invasive treatments, conventional radiotherapy in spinal and non-spinal bone metastases, bone-targeting radionuclides and bone-modifying agents in achieving palliation. We present the clinical data and their associated toxicity. Recent advances are also discussed.
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26
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Pirooznia N, Abdi K, Beiki D, Emami F, Arab SS, Sabzevari O, Soltani-Gooshkhaneh S. 177Lu-labeled cyclic RGD peptide as an imaging and targeted radionuclide therapeutic agent in non-small cell lung cancer: Biological evaluation and preclinical study. Bioorg Chem 2020; 102:104100. [PMID: 32711088 DOI: 10.1016/j.bioorg.2020.104100] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2020] [Revised: 07/10/2020] [Accepted: 07/11/2020] [Indexed: 12/29/2022]
Abstract
Non-small cell lung carcinoma (NSCLC) is among the most lethal lung cancers responsible for 80-85% of death. αvβ3 integrin receptor subtype has been identified as a lung cancer biomarker since its expression correlates with tumor progression and metastasis. The extracellular domain of the receptor forms a binding site for RGD-based sequences. Therefore, specific targeting of αvβ3 integrin receptors by these short peptides can be an excellent candidate for cancer imaging and therapy. In this research, the radiolabeling of DOTA-E(cRGDfK)2 with 177Lu was efficiently implemented. The Log P value, in vivo, in vitro, metabolic stability, cellular uptake and specific binding of the radiopeptide was determined. The tumor targeting capacity and the therapeutic potential of the radiotracer was studied in A549 tumor-bearing mice. Imaging studies at different time intervals were performed by SPECT/CT. Radiochemical purity of more than 99% and Log P of -3.878 was obtained for 177Lu-labelled peptide. Radiotracer showed favorable in vivo, in vitro and metabolic stability. The radiopeptide dissociation constant (Kd) was 15.07 nM. Radiopeptide specific binding was more than 95%. Biodistribution studies showed high accumulation of the radiopeptide in tumor and rapid excretion by urinary route. Maximum tumor uptake was at 4 h post-injection. Following administration of this radiopeptide to mice, not only tumor growth was suppressed, but significant tumor shrinkage was also observed. In conclusion, this radiopeptide can be employed for staging, follow-up imaging and as peptide receptor radionuclide therapeutic agent allowing efficient therapy for NSCLC and other cancers overexpressing αvβ3 integrin receptors.
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Affiliation(s)
- Nazanin Pirooznia
- Department of Radiopharmacy, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran
| | - Khosrou Abdi
- Department of Radiopharmacy, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran.
| | - Davood Beiki
- Research Center for Nuclear Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Farshad Emami
- Nuclear Medicine and Molecular Imaging Department, Imam Reza International University, Razavi Hospital, Mashhad, Iran
| | - Seyed Shahriar Arab
- Department of Biophysics, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran
| | - Omid Sabzevari
- Department of Toxicology and Pharmacology, Faculty of Pharmacy, Toxicology and Poisoning Research Centre, Tehran University of Medical Sciences, Tehran, Iran; Toxicology and Poisoning Research Centre, Tehran University of Medical Sciences, Tehran, Iran
| | - Samira Soltani-Gooshkhaneh
- Nuclear Medicine and Molecular Imaging Department, Imam Reza International University, Razavi Hospital, Mashhad, Iran
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27
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Wilson TC, Jannetti SA, Guru N, Pillarsetty N, Reiner T, Pirovano G. Improved radiosynthesis of 123I-MAPi, an auger theranostic agent. Int J Radiat Biol 2020; 99:70-76. [PMID: 32552309 PMCID: PMC7775866 DOI: 10.1080/09553002.2020.1781283] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Revised: 05/15/2020] [Accepted: 05/20/2020] [Indexed: 01/17/2023]
Abstract
PURPOSE 123I-MAPi, a novel PARP1-targeted Auger radiotherapeutic has shown promising results in pre-clinical glioma model. Currently, 123I-MAPi is synthesized using multistep synthesis that results in modest yields and low molar activities (MA) that limits the ability to translate this technology for human studies where high doses are administered. Therefore, new methods are needed to synthesize 123I-MAPi in high activity yields (AY) and improved MA to facilitate clinical translation and multicenter trials. MATERIALS AND METHODS 123I-MAPi was prepared in a single step via 123I-iododetannylation of the corresponding tributylstannane precursor. In vitro internalization assay, subcellular fractionation and confocal microscopy where used to evaluate the performance of 123I-MAPi in a small cell lung cancer model. RESULTS 123I-MAPi was synthesized in a single step from the corresponding stannane precursor in AY of 45 ± 2% and MA of 11.8 ± 4.8 GBq µmol-1. In vitro in LX22 cells showed rapid internalization (5 min) with accumulation found predominantly in the membrane, nucleus and chromatin of the cell as determined by subcellular fractionation. CONCLUSIONS Here, we have developed an improved radiosynthesis of 123I-MAPi, an Auger theranostic agent. This process was achieved using a single step, 123I-iododestannylation reaction from the corresponding stannane precursor in good AY and MA. 123I-MAPi was evaluated in vitro in a small cell lung cancer model with high PARP expression, rapid internalization and high nuclear uptake shown.
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Affiliation(s)
- Thomas C Wilson
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Stephen A Jannetti
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY, USA
- Department of Biochemistry, Hunter College, The City University of New York (CUNY), New York, NY, USA
- Program in Biochemistry, The Graduate Center, CUNY, New York, NY, USA
| | - Navjot Guru
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | | | - Thomas Reiner
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY, USA
- Department of Radiology, Weill Cornell Medical College, New York, NY, USA
- Chemical Biology Program, Memorial Sloan Kettering Cancer Center, New York City, NY, USA
| | - Giacomo Pirovano
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY, USA
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Tosato M, Nardella S, Badocco D, Pastore P, Andrighetto A, Realdon N, Di Marco V. Chemical purification of 111Ag from isobaric impurity 111Cd by solid phase extraction chromatography: a proof of concept study. Appl Radiat Isot 2020; 164:109263. [PMID: 32554124 DOI: 10.1016/j.apradiso.2020.109263] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Accepted: 06/01/2020] [Indexed: 01/20/2023]
Abstract
Silver-111 (111Ag, t1/2 = 7.47 d) is a β- emitter suitable for targeted cancer therapy due to favourable decay properties. The production of no-carrier added 111Ag via Isotope Separation On-Line (ISOL) technique is being investigated at the Legnaro National Laboratories of the Italian Institute of Nuclear Physics (ISOLPHARM project). Stable Cadmium-111 (111Cd) is co-produced as isobaric contaminant, hence a chemical separation process must be developed to selectively harvest 111Ag. In this study, a chromatographic procedure employing the commercially available CL resin was investigated by using stable Ag+ and Cd2+. Results indicate that CL resin allows to efficiently separate Ag+ from Cd2+ and recover the former with high yields.
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Affiliation(s)
- Marianna Tosato
- Department of Chemical Sciences, University of Padova, Via Marzolo 1, 35131, Padova, Italy
| | - Sonia Nardella
- Department of Chemical Sciences, University of Padova, Via Marzolo 1, 35131, Padova, Italy
| | - Denis Badocco
- Department of Chemical Sciences, University of Padova, Via Marzolo 1, 35131, Padova, Italy
| | - Paolo Pastore
- Department of Chemical Sciences, University of Padova, Via Marzolo 1, 35131, Padova, Italy
| | - Alberto Andrighetto
- Italian Institute of Nuclear Physics, Legnaro National Laboratories, Viale dell'Università 2, 35020, Legnaro, Padova, Italy
| | - Nicola Realdon
- Department of Pharmaceutical Sciences, University of Padova, Via Marzolo 5, 35131, Padova, Italy
| | - Valerio Di Marco
- Department of Chemical Sciences, University of Padova, Via Marzolo 1, 35131, Padova, Italy.
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29
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Pirovano G, Jannetti SA, Carter LM, Sadique A, Kossatz S, Guru N, Demétrio De Souza França P, Maeda M, Zeglis BM, Lewis JS, Humm JL, Reiner T. Targeted Brain Tumor Radiotherapy Using an Auger Emitter. Clin Cancer Res 2020; 26:2871-2881. [PMID: 32066626 PMCID: PMC7299758 DOI: 10.1158/1078-0432.ccr-19-2440] [Citation(s) in RCA: 64] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Revised: 10/07/2019] [Accepted: 02/12/2020] [Indexed: 12/20/2022]
Abstract
PURPOSE Glioblastoma multiforme is a highly aggressive form of brain cancer whose location, tendency to infiltrate healthy surrounding tissue, and heterogeneity significantly limit survival, with scant progress having been made in recent decades. EXPERIMENTAL DESIGN 123I-MAPi (Iodine-123 Meitner-Auger PARP1 inhibitor) is a precise therapeutic tool composed of a PARP1 inhibitor radiolabeled with an Auger- and gamma-emitting iodine isotope. Here, the PARP inhibitor, which binds to the DNA repair enzyme PARP1, specifically targets cancer cells, sparing healthy tissue, and carries a radioactive payload within reach of the cancer cells' DNA. RESULTS The high relative biological efficacy of Auger electrons within their short range of action is leveraged to inflict DNA damage and cell death with high precision. The gamma ray emission of 123I-MAPi allows for the imaging of tumor progression and therapy response, and for patient dosimetry calculation. Here we demonstrated the efficacy and specificity of this small-molecule radiotheranostic in a complex preclinical model. In vitro and in vivo studies demonstrate high tumor uptake and a prolonged survival in mice treated with 123I-MAPi when compared with vehicle controls. Different methods of drug delivery were investigated to develop this technology for clinical applications, including convection enhanced delivery and intrathecal injection. CONCLUSIONS Taken together, these results represent the first full characterization of an Auger-emitting PARP inhibitor which demonstrate a survival benefit in mouse models of GBM and confirm the high potential of 123I-MAPi for clinical translation.
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Affiliation(s)
- Giacomo Pirovano
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Stephen A Jannetti
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
- Department of Biochemistry, Hunter College, The City University of New York (CUNY), New York, New York
- PhD Program in Biochemistry, The Graduate Center, The City University of New York (CUNY), New York, New York
| | - Lukas M Carter
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Ahmad Sadique
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Susanne Kossatz
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Navjot Guru
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
| | | | - Masatomo Maeda
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Brian M Zeglis
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
- Department of Chemistry, Hunter College, The City University of New York (CUNY), New York, New York
- Department of Radiology, Weill Cornell Medical College, New York, New York
- PhD Program in Chemistry, The Graduate Center, The City University of New York (CUNY), New York, New York
| | - Jason S Lewis
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
- Department of Radiology, Weill Cornell Medical College, New York, New York
- Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, New York
- Department of Pharmacology, Weill Cornell Medical College, New York, New York
| | - John L Humm
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Thomas Reiner
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York.
- Department of Radiology, Weill Cornell Medical College, New York, New York
- Chemical Biology Program, Memorial Sloan Kettering Cancer Center, New York, New York
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30
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Ruigrok EAM, van Weerden WM, Nonnekens J, de Jong M. The Future of PSMA-Targeted Radionuclide Therapy: An Overview of Recent Preclinical Research. Pharmaceutics 2019; 11:E560. [PMID: 31671763 PMCID: PMC6921028 DOI: 10.3390/pharmaceutics11110560] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Revised: 10/23/2019] [Accepted: 10/24/2019] [Indexed: 12/15/2022] Open
Abstract
Prostate specific membrane antigen (PSMA) has become a major focus point in the research and development of prostate cancer (PCa) imaging and therapeutic strategies using radiolabeled tracers. PSMA has shown to be an excellent target for PCa theranostics because of its high expression on the membrane of PCa cells and the increase in expression during disease progression. Therefore, numerous PSMA-targeting tracers have been developed and (pre)clinically studied with promising results. However, many of these PSMA-targeting tracers show uptake in healthy organs such as the salivary glands, causing radiotoxicity. Furthermore, not all patients respond to PSMA-targeted radionuclide therapy (TRT). This created the necessity of additional preclinical research studies in which existing tracers are reevaluated and new tracers are developed in order to improve PSMA-TRT by protecting the (PSMA-expressing) healthy organs and improving tumor uptake. In this review we will give an overview of the recent preclinical research projects regarding PCa-TRT using PSMA-specific radiotracers, which will give an indication of where the PSMA-TRT research movement is going and what we can expect in future clinical trials.
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Affiliation(s)
- Eline A M Ruigrok
- Dept. of Radiology and Nuclear Medicine, Erasmus MC, 3015 GD Rotterdam, The Netherlands.
- Dept. of Experimental Urology, Erasmus MC, 3015 GD Rotterdam, The Netherlands.
| | | | - Julie Nonnekens
- Dept. of Radiology and Nuclear Medicine, Erasmus MC, 3015 GD Rotterdam, The Netherlands.
- Dept. of Molecular Genetics, Erasmus MC, 3015 GD Rotterdam, The Netherlands.
- Oncode Institute, Erasmus MC, 3015 GD Rotterdam, The Netherlands.
| | - Marion de Jong
- Dept. of Radiology and Nuclear Medicine, Erasmus MC, 3015 GD Rotterdam, The Netherlands.
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31
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Patel GK, Chugh N, Tripathi M. Neuroendocrine Differentiation of Prostate Cancer-An Intriguing Example of Tumor Evolution at Play. Cancers (Basel) 2019; 11:E1405. [PMID: 31547070 PMCID: PMC6826557 DOI: 10.3390/cancers11101405] [Citation(s) in RCA: 65] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Revised: 09/09/2019] [Accepted: 09/17/2019] [Indexed: 02/07/2023] Open
Abstract
Our understanding of neuroendocrine prostate cancer (NEPC) has assumed a new perspective in light of the recent advances in research. Although classical NEPC is rarely seen in the clinic, focal neuroendocrine trans-differentiation of prostate adenocarcinoma occurs in about 30% of advanced prostate cancer (PCa) cases, and represents a therapeutic challenge. Even though our knowledge of the mechanisms that mediate neuroendocrine differentiation (NED) is still evolving, the role of androgen deprivation therapy (ADT) as a key driver of this phenomenon is increasingly becoming evident. In this review, we discuss the molecular, cellular, and therapeutic mediators of NED, and emphasize the role of the tumor microenvironment (TME) in orchestrating the phenotype. Understanding the role of the TME in mediating NED could provide us with valuable insights into the plasticity associated with the phenotype, and reveal potential therapeutic targets against this aggressive form of PCa.
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Affiliation(s)
- Girijesh Kumar Patel
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA.
| | - Natasha Chugh
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA.
| | - Manisha Tripathi
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA.
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Siwowska K, Guzik P, Domnanich KA, Monné Rodríguez JM, Bernhardt P, Ponsard B, Hasler R, Borgna F, Schibli R, Köster U, van der Meulen NP, Müller C. Therapeutic Potential of 47Sc in Comparison to 177Lu and 90Y: Preclinical Investigations. Pharmaceutics 2019; 11:pharmaceutics11080424. [PMID: 31434360 PMCID: PMC6723926 DOI: 10.3390/pharmaceutics11080424] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2019] [Revised: 08/13/2019] [Accepted: 08/15/2019] [Indexed: 12/14/2022] Open
Abstract
Targeted radionuclide therapy with 177Lu- and 90Y-labeled radioconjugates is a clinically-established treatment modality for metastasized cancer. 47Sc is a therapeutic radionuclide that decays with a half-life of 3.35 days and emits medium-energy β−-particles. In this study, 47Sc was investigated, in combination with a DOTA-folate conjugate, and compared to the therapeutic properties of 177Lu-folate and 90Y-folate, respectively. In vitro, 47Sc-folate demonstrated effective reduction of folate receptor-positive ovarian tumor cell viability similar to 177Lu-folate, but 90Y-folate was more potent at equal activities due to the higher energy of emitted β−-particles. Comparable tumor growth inhibition was observed in mice that obtained the same estimated absorbed tumor dose (~21 Gy) when treated with 47Sc-folate (12.5 MBq), 177Lu-folate (10 MBq), and 90Y-folate (5 MBq), respectively. The treatment resulted in increased median survival of 39, 43, and 41 days, respectively, as compared to 26 days in untreated controls. There were no statistically significant differences among the therapeutic effects observed in treated groups. Histological assessment revealed no severe side effects two weeks after application of the radiofolates, even at double the activity used for therapy. Based on the decay properties and our results, 47Sc is likely to be comparable to 177Lu when employed for targeted radionuclide therapy. It may, therefore, have potential for clinical translation and be of particular interest in tandem with 44Sc or 43Sc as a diagnostic match, enabling the realization of radiotheragnostics in future.
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Affiliation(s)
- Klaudia Siwowska
- Center for Radiopharmaceutical Sciences ETH-PSI-USZ, Paul Scherrer Institute, 5232 Villigen-PSI, Switzerland
| | - Patrycja Guzik
- Center for Radiopharmaceutical Sciences ETH-PSI-USZ, Paul Scherrer Institute, 5232 Villigen-PSI, Switzerland
| | - Katharina A Domnanich
- Laboratory of Radiochemistry, Paul Scherrer Institute, 5232 Villigen-PSI, Switzerland
- Department of Chemistry and Biochemistry University of Bern, 3012 Bern, Switzerland
| | - Josep M Monné Rodríguez
- Laboratory for Animal Model Pathology (LAMP), Institute of Veterinary Pathology, Vetsuisse Faculty, University of Zurich, 8057 Zurich, Switzerland
| | - Peter Bernhardt
- Department of Radiation Physics, The Sahlgrenska Academy, University of Gothenburg, 41345 Gothenburg, Sweden
- Department of Medical Physics and Medical Bioengineering, Sahlgrenska University Hospital, 41345 Gothenburg, Sweden
| | - Bernard Ponsard
- SCK.CEN, Belgian Nuclear Research Centre, BR2 Reactor, 2400 Mol, Belgium
| | - Roger Hasler
- Center for Radiopharmaceutical Sciences ETH-PSI-USZ, Paul Scherrer Institute, 5232 Villigen-PSI, Switzerland
| | - Francesca Borgna
- Center for Radiopharmaceutical Sciences ETH-PSI-USZ, Paul Scherrer Institute, 5232 Villigen-PSI, Switzerland
| | - Roger Schibli
- Center for Radiopharmaceutical Sciences ETH-PSI-USZ, Paul Scherrer Institute, 5232 Villigen-PSI, Switzerland
- Department of Chemistry and Applied Biosciences, ETH Zurich, 8092 Zurich, Switzerland
| | - Ulli Köster
- Institut Laue Langevin, 38042 Grenoble, France
| | - Nicholas P van der Meulen
- Center for Radiopharmaceutical Sciences ETH-PSI-USZ, Paul Scherrer Institute, 5232 Villigen-PSI, Switzerland
- Laboratory of Radiochemistry, Paul Scherrer Institute, 5232 Villigen-PSI, Switzerland
| | - Cristina Müller
- Center for Radiopharmaceutical Sciences ETH-PSI-USZ, Paul Scherrer Institute, 5232 Villigen-PSI, Switzerland.
- Department of Chemistry and Applied Biosciences, ETH Zurich, 8092 Zurich, Switzerland.
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