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Goswami M, Toro-González M, Moon J, Davern S. Precision Atomistic Structures of Actinium-/Radium-/Barium-Doped Lanthanide Nanoconstructs for Radiotherapeutic Applications. ACS NANO 2024. [PMID: 38885179 DOI: 10.1021/acsnano.3c13213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/20/2024]
Abstract
Lanthanide vanadate (LnVO4) nanoconstructs have generated considerable interest in radiotherapeutic applications as a medium for nanoscale-targeted drug delivery. For cancer treatment, LnVO4 nanoconstructs have shown promise in encapsulating and retaining radionuclides that emit alpha-particles. In this work, we examined the structure formation of LnVO4 nanoconstructs doped with actinium (Ac) and radium (Ra), both experimentally and using large-scale atomistic molecular dynamics simulations. LnVO4 nanoconstructs were synthesized via a precipitation method in aqueous media. The reaction conditions and elemental compositions were varied to control the structure, fluorescence properties, and size distribution of the LnVO4 nanoconstructs. LnVO4 nanoconstructs were characterized by X-ray diffraction, Raman spectroscopy, and fluorescence spectroscopy. Molecular dynamics simulations were performed to obtain a fundamental understanding of the structure-property relationship between radionuclides and LnVO4 nanoconstructs at the atomic length scale. Molecular dynamics simulations with well-established force field (FF) parameters show that Ra atoms tend to distribute across the nanoconstructs' surface in a broader coordination shell, while the Ac atoms are arranged inside a smaller coordination shell within the nanocluster. The Ba atoms prefer to self-assemble around the surface. These theoretical/simulation predictions of the atomistic structures and an understanding of the relationship between radionuclides and LnVO4 nanoconstructs at the atomic scale are important because they provide design principles for the future development of nanoconstructs for targeted radionuclide delivery.
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Affiliation(s)
- Monojoy Goswami
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Miguel Toro-González
- Radioisotope Science & Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Jisue Moon
- Radioisotope Science & Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Sandra Davern
- Radioisotope Science & Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
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2
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Toro-González M, Akingbesote N, Bible A, Pal D, Sanders B, Ivanov AS, Jansone-Popova S, Popovs I, Benny P, Perry R, Davern S. Development of 225Ac-doped biocompatible nanoparticles for targeted alpha therapy. J Nanobiotechnology 2024; 22:306. [PMID: 38825717 PMCID: PMC11145892 DOI: 10.1186/s12951-024-02520-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2024] [Accepted: 05/01/2024] [Indexed: 06/04/2024] Open
Abstract
Targeted alpha therapy (TAT) relies on chemical affinity or active targeting using radioimmunoconjugates as strategies to deliver α-emitting radionuclides to cancerous tissue. These strategies can be affected by transmetalation of the parent radionuclide by competing ions in vivo and the bond-breaking recoil energy of decay daughters. The retention of α-emitting radionuclides and the dose delivered to cancer cells are influenced by these processes. Encapsulating α-emitting radionuclides within nanoparticles can help overcome many of these challenges. Poly(lactic-co-glycolic acid) (PLGA) nanoparticles are a biodegradable and biocompatible delivery platform that has been used for drug delivery. In this study, PLGA nanoparticles are utilized for encapsulation and retention of actinium-225 ([225Ac]Ac3+). Encapsulation of [225Ac]Ac3+ within PLGA nanoparticles (Zave = 155.3 nm) was achieved by adapting a double-emulsion solvent evaporation method. The encapsulation efficiency was affected by both the solvent conditions and the chelation of [225Ac]Ac3+. Chelation of [225Ac]Ac3+ to a lipophilic 2,9-bis-lactam-1,10-phenanthroline ligand ([225Ac]AcBLPhen) significantly decreased its release (< 2%) and that of its decay daughters (< 50%) from PLGA nanoparticles. PLGA nanoparticles encapsulating [225Ac]AcBLPhen significantly increased the delivery of [225Ac]Ac3+ to murine (E0771) and human (MCF-7 and MDA-MB-231) breast cancer cells with a concomitant increase in cell death over free [225Ac]Ac3+ in solution. These results demonstrate that PLGA nanoparticles have potential as radionuclide delivery platforms for TAT to advance precision radiotherapy for cancer. In addition, this technology offers an alternative use for ligands with poor aqueous solubility, low stability, or low affinity, allowing them to be repurposed for TAT by encapsulation within PLGA nanoparticles.
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Affiliation(s)
- Miguel Toro-González
- Isotope Science and Engineering Directorate, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, TN, 37830, USA
| | - Ngozi Akingbesote
- Isotope Science and Engineering Directorate, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, TN, 37830, USA
- Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, CT, 06510, USA
| | - Amber Bible
- Biological and Environmental Systems Science Directorate, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, TN, 37830, USA
| | - Debjani Pal
- Isotope Science and Engineering Directorate, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, TN, 37830, USA
| | - Brian Sanders
- Biological and Environmental Systems Science Directorate, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, TN, 37830, USA
| | - Alexander S Ivanov
- Physical Sciences Directorate, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, TN, 37830, USA
| | - Santa Jansone-Popova
- Physical Sciences Directorate, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, TN, 37830, USA
| | - Ilja Popovs
- Physical Sciences Directorate, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, TN, 37830, USA
| | - Paul Benny
- Isotope Science and Engineering Directorate, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, TN, 37830, USA
| | - Rachel Perry
- Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, CT, 06510, USA
| | - Sandra Davern
- Isotope Science and Engineering Directorate, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, TN, 37830, USA.
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Ree SM, Greenwood H, Young JD, Roberts R, Livens FR, Heath SL, Sosabowski JK. Selection of radionuclide(s) for targeted alpha therapy based on their nuclear decay properties. Nucl Med Commun 2024; 45:465-473. [PMID: 38465420 DOI: 10.1097/mnm.0000000000001832] [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: 03/12/2024]
Abstract
Targeted alpha therapy (TAT) is a promising form of oncology treatment utilising alpha-emitting radionuclides that can specifically accumulate at disease sites. The high energy and high linear energy transfer associated with alpha emissions causes localised damage at target sites whilst minimising that to surrounding healthy tissue. The lack of appropriate radionuclides has inhibited research in TAT. The identification of appropriate radionuclides should be primarily a function of the radionuclide's nuclear decay properties, and not their biochemistry or economic factors since these last two factors can change; however, the nuclear decay properties are fixed to that nuclide. This study has defined and applied a criterion based on nuclear decay properties useful for TAT. This down-selection exercise concluded that the most appropriate radionuclides are: 149 Tb, 211 At/ 211 Po, 212 Pb/ 212 Bi/ 212 Po, 213 Bi/ 213 Po, 224 Ra, 225 Ra/ 225 Ac/ 221 Fr, 226 Ac/ 226 Th, 227 Th/ 223 Ra/ 219 Rn, 229 U, 230 U/ 226 Th, and 253 Fm, the majority of which have previously been considered for TAT. 229 U and 253 Fm have been newly identified and could become new radionuclides of interest for TAT, depending on their decay chain progeny.
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Affiliation(s)
- Samantha M Ree
- National Nuclear Laboratory, Springfields, Salwick, Preston, Lancashire
| | - Howard Greenwood
- National Nuclear Laboratory, Springfields, Salwick, Preston, Lancashire
| | - Jennifer D Young
- School of Biomedical Engineering and Imaging Sciences, King's College London, London
| | - Rachel Roberts
- National Nuclear Laboratory, Springfields, Salwick, Preston, Lancashire
| | | | - Scott L Heath
- Department of Earth and Environmental Sciences, The University of Manchester, Manchester and
| | - Jane K Sosabowski
- Centre for Cancer Biomarkers and Biotherapeutics, Barts Cancer Institute, Queen Mary University of London, London
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Kleynhans J, Ebenhan T, Cleeren F, Sathekge MM. Can current preclinical strategies for radiopharmaceutical development meet the needs of targeted alpha therapy? Eur J Nucl Med Mol Imaging 2024; 51:1965-1980. [PMID: 38676735 PMCID: PMC11139742 DOI: 10.1007/s00259-024-06719-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Accepted: 04/15/2024] [Indexed: 04/29/2024]
Abstract
Preclinical studies are essential for effectively evaluating TAT radiopharmaceuticals. Given the current suboptimal supply chain of these radionuclides, animal studies must be refined to produce the most translatable TAT agents with the greatest clinical potential. Vector design is pivotal, emphasizing harmonious physical and biological characteristics among the vector, target, and radionuclide. The scarcity of alpha-emitting radionuclides remains a significant consideration. Actinium-225 and lead-212 appear as the most readily available radionuclides at this stage. Available animal models for researchers encompass xenografts, allografts, and PDX (patient-derived xenograft) models. Emerging strategies for imaging alpha-emitters are also briefly explored. Ultimately, preclinical research must address two critical aspects: (1) offering valuable insights into balancing safety and efficacy, and (2) providing guidance on the optimal dosing of the TAT agent.
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Affiliation(s)
- Janke Kleynhans
- Laboratory for Radiopharmaceutical Research, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Leuven, 3000, Belgium
| | - Thomas Ebenhan
- Department of Nuclear Medicine, University of Pretoria, and Steve Biko Academic Hospital, Pretoria, 0001, South Africa
- Department of Nuclear Medicine, Steve Biko Academic Hospital, Pretoria, 0001, South Africa
| | - Frederik Cleeren
- Laboratory for Radiopharmaceutical Research, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Leuven, 3000, Belgium
| | - Mike Machaba Sathekge
- Department of Nuclear Medicine, Steve Biko Academic Hospital, Pretoria, 0001, South Africa.
- Preclinical Imaging Facility, Nuclear Medicine Research Infrastructure, Pretoria, 0001, South Africa.
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Diaz-Martinez VD, Cyr M, Devic S, Tomic N, Lewis DF, Enger SA. Investigation of dosimetric characteristics of radiochromic film in response to alpha particles emitted from Americium-241. Med Phys 2024. [PMID: 38767310 DOI: 10.1002/mp.17133] [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: 08/26/2023] [Revised: 02/15/2024] [Accepted: 03/15/2024] [Indexed: 05/22/2024] Open
Abstract
BACKGROUND In radiotherapy, it is essential to deliver prescribed doses to tumors while minimizing damage to surrounding healthy tissue. Accurate measurements of absorbed dose are required for this purpose. Gafchromic® external beam therapy (EBT) radiochromic films have been widely used in radiotherapy. While the dosimetric characteristics of the EBT3 model film have been extensively studied for photon and charged particle beams (protons, electrons, and carbon ions), little research has been done on α $\alpha$ -particle dosimetry. α $\alpha$ -emitting radionuclides have gained popularity in cancer treatment due to their high linear energy transfer, short range in tissue, and ability to spare surrounding organs at risk, thereby delivering a more localized dose distribution to the tumor. Therefore, a dose-calibration film protocol for α $\alpha$ -particles is required. PURPOSE This study aimed to develop a dose-calibration protocol for the α $\alpha$ -particle emitting radionuclide 241Am, using Monte Carlo (MC) simulations and measurements with unlaminated EBT3 films. METHODS In this study, a MC-based user code was developed using the Geant4 simulation toolkit to model and simulate an 241Am source and an unlaminated EBT3 film. Two simulations were performed: one with voxelized geometries of the EBT3 active volume composition and the other using water. The dose rate was calculated within a region of interest in the voxelized geometries. Unlaminated EBT3 film pieces were irradiated with the 241Am source at various exposure times inside a black box. Film irradiations were compared to a 6-MV photon beam from a Varian TrueBeam machine. The simulated dose rate was used to convert the exposure times into absorbed doses to water, describing a radiochromic-film-based reference dosimetry protocol for α $\alpha$ -particles. The irradiated films were scanned and through an in-house Python script, the normalized pixel values from the green-color channel of scanned film images were analyzed. RESULTS The 241Am energy spectra obtained from the simulations were in good agreement with IAEA and NIST databases, having differences < $<$ 0.516% for the emitted γ $\gamma$ -rays and produced characteristic x-rays and < $<$ 0.006% for the α $\alpha$ -particles. Due to the short range of α $\alpha$ -particles, there was no energy deposition in the voxels outside the active 241Am source region projected onto the film surface. Thus, the total dose rate within the voxels covering the source was 0.847 ± $\pm$ 0.003 Gy/min within the sensitive layer of the film (LiPCDA) and 0.847 ± $\pm$ 0.004 Gy/min in water, indicating that the active volume can be considered water equivalent for the 241Am beam quality. A novel approach was employed in α $\alpha$ -film dosimetry using an exponential fit for the green channel, which showed promising results by reducing the uncertainty in dose estimation within 5%. Although the statistical analysis did not reveal significant differences between the 6-MV photon beam and the α $\alpha$ calibration curves, the dose-response curves exhibited the expected behavior. CONCLUSIONS The developed MC user code simulated the experimental setup for α $\alpha$ -dosimetry using radiochromic film with acceptable uncertainty. Unlaminated EBT3 film is suitable for the dosimetry of α $\alpha$ -radiation at low doses and can be used in conjunction with other unlaminated GafChromic® films for quality assurance and research purposes.
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Affiliation(s)
- Victor D Diaz-Martinez
- Medical Physics Unit, Department of Oncology, Faculty of Medicine, McGill University, Montréal, Québec, Canada
| | - Mélodie Cyr
- Medical Physics Unit, Department of Oncology, Faculty of Medicine, McGill University, Montréal, Québec, Canada
| | - Slobodan Devic
- Medical Physics Unit, Department of Oncology, Faculty of Medicine, McGill University, Montréal, Québec, Canada
- Lady Davis Institute for Medical Research, Jewish General Hospital, Montréal, Québec, Canada
| | - Nada Tomic
- Medical Physics Unit, Department of Oncology, Faculty of Medicine, McGill University, Montréal, Québec, Canada
- Lady Davis Institute for Medical Research, Jewish General Hospital, Montréal, Québec, Canada
| | | | - Shirin A Enger
- Medical Physics Unit, Department of Oncology, Faculty of Medicine, McGill University, Montréal, Québec, Canada
- Lady Davis Institute for Medical Research, Jewish General Hospital, Montréal, Québec, Canada
- Research Institute of McGill University Health Centre, Montréal, Québec, Canada
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Binmujlli MA. Radiological and Molecular Analysis of Radioiodinated Anastrozole and Epirubicin as Innovative Radiopharmaceuticals Targeting Methylenetetrahydrofolate Dehydrogenase 2 in Solid Tumors. Pharmaceutics 2024; 16:616. [PMID: 38794278 PMCID: PMC11126143 DOI: 10.3390/pharmaceutics16050616] [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: 02/20/2024] [Revised: 04/13/2024] [Accepted: 04/18/2024] [Indexed: 05/26/2024] Open
Abstract
In the dynamic field of radiopharmaceuticals, innovating targeted agents for cancer diagnosis and therapy is crucial. Our study enriches this evolving landscape by evaluating the potential of radioiodinated anastrozole ([125I]anastrozole) and radioiodinated epirubicin ([125I]epirubicin) as targeting agents against MTHFD2-driven tumors. MTHFD2, which is pivotal in one-carbon metabolism, is notably upregulated in various cancers, presenting a novel target for radiopharmaceutical application. Through molecular docking and 200 ns molecular dynamics (MD) simulations, we assess the binding efficiency and stability of [125I]anastrozole and [125I]epirubicin with MTHFD2. Molecular docking illustrates that [125I]epirubicin has a superior binding free energy (∆Gbind) of -41.25 kJ/mol compared to -39.07 kJ/mol for [125I]anastrozole and -38.53 kJ/mol for the control ligand, suggesting that it has a higher affinity for MTHFD2. MD simulations reinforce this, showing stable binding, as evidenced by root mean square deviation (RMSD) values within a narrow range, underscoring the structural integrity of the enzyme-ligand complexes. The root mean square fluctuation (RMSF) analysis indicates consistent dynamic behavior of the MTHFD2 complex upon binding with [125I]anastrozole and [125I]epirubicin akin to the control. The radius of gyration (RG) measurements of 16.90 Å for MTHFD2-[125I]anastrozole and 16.84 Å for MTHFD2-[125I]epirubicin confirm minimal structural disruption upon binding. The hydrogen bond analysis reveals averages of two and three stable hydrogen bonds for [125I]anastrozole and [125I]epirubicin complexes, respectively, highlighting crucial stabilizing interactions. The MM-PBSA calculations further endorse the thermodynamic favorability of these interactions, with binding free energies of -48.49 ± 0.11 kJ/mol for [125I]anastrozole and -43.8 kJ/mol for MTHFD2-. The significant contribution of Van der Waals and electrostatic interactions to the binding affinities of [125I]anastrozole and [125I]epirubicin, respectively, underscores their potential efficacy for targeted tumor imaging and therapy. These computational findings lay the groundwork for the future experimental validation of [125I]anastrozole and [125I]epirubicin as MTHFD2 inhibitors, heralding a notable advancement in precision oncology tools. The data necessitate subsequent in vitro and in vivo assays to corroborate these results.
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Affiliation(s)
- Mazen Abdulrahman Binmujlli
- Department of Internal Medicine, College of Medicine, Imam Mohammad Ibn Saud Islamic University (IMSIU), P.O. Box 90950, Riyadh 11623, Saudi Arabia
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Li Z, Benabdallah N, Luo J, Wahl RL, Thorek DLJ, Jha AK. ISIT-QA: In Silico Imaging Trial to Evaluate a Low-Count Quantitative SPECT Method Across Multiple Scanner-Collimator Configurations for 223Ra-Based Radiopharmaceutical Therapies. J Nucl Med 2024; 65:810-817. [PMID: 38575187 PMCID: PMC11064831 DOI: 10.2967/jnumed.123.266719] [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: 09/19/2023] [Revised: 02/13/2024] [Indexed: 04/06/2024] Open
Abstract
Personalized dose-based treatment planning requires accurate and reproducible noninvasive measurements to ensure safety and effectiveness. Dose estimation using SPECT is possible but challenging for alpha (α)-particle-emitting radiopharmaceutical therapy (α-RPT) because of complex γ-emission spectra, extremely low counts, and various image-degrading artifacts across a plethora of scanner-collimator configurations. Through the incorporation of physics-based considerations and skipping of the potentially lossy voxel-based reconstruction step, a recently developed projection-domain low-count quantitative SPECT (LC-QSPECT) method has the potential to provide reproducible, accurate, and precise activity concentration and dose measures across multiple scanners, as is typically the case in multicenter settings. To assess this potential, we conducted an in silico imaging trial to evaluate the LC-QSPECT method for a 223Ra-based α-RPT, with the trial recapitulating patient and imaging system variabilities. Methods: A virtual imaging trial titled In Silico Imaging Trial for Quantitation Accuracy (ISIT-QA) was designed with the objectives of evaluating the performance of the LC-QSPECT method across multiple scanner-collimator configurations and comparing performance with a conventional reconstruction-based quantification method. In this trial, we simulated 280 realistic virtual patients with bone-metastatic castration-resistant prostate cancer treated with 223Ra-based α-RPT. The trial was conducted with 9 simulated SPECT scanner-collimator configurations. The primary objective of this trial was to evaluate the reproducibility of dose estimates across multiple scanner-collimator configurations using LC-QSPECT by calculating the intraclass correlation coefficient. Additionally, we compared the reproducibility and evaluated the accuracy of both considered quantification methods across multiple scanner-collimator configurations. Finally, the repeatability of the methods was evaluated in a test-retest study. Results: In this trial, data from 268 223RaCl2 treated virtual prostate cancer patients, with a total of 2,903 lesions, were used to evaluate LC-QSPECT. LC-QSPECT provided dose estimates with good reproducibility across the 9 scanner-collimator configurations (intraclass correlation coefficient > 0.75) and high accuracy (ensemble average values of recovery coefficients ranged from 1.00 to 1.02). Compared with conventional reconstruction-based quantification, LC-QSPECT yielded significantly improved reproducibility across scanner-collimator configurations, accuracy, and test-retest repeatability ([Formula: see text] Conclusion: LC-QSPECT provides reproducible, accurate, and repeatable dose estimations in 223Ra-based α-RPT as evaluated in ISIT-QA. These findings provide a strong impetus for multicenter clinical evaluations of LC-QSPECT in dose quantification for α-RPTs.
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Affiliation(s)
- Zekun Li
- Department of Biomedical Engineering, Washington University, St. Louis, Missouri
| | - Nadia Benabdallah
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, Missouri
- Program in Quantitative Molecular Therapeutics, Washington University, St. Louis, Missouri
| | - Jingqin Luo
- Siteman Cancer Center, Washington University, St. Louis, Missouri
- Division of Public Health Sciences, Department of Surgery, Washington University, St. Louis, Missouri; and
- Division of Biostatistics, Washington University, St. Louis, Missouri
| | - Richard L Wahl
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, Missouri
- Siteman Cancer Center, Washington University, St. Louis, Missouri
| | - Daniel L J Thorek
- Department of Biomedical Engineering, Washington University, St. Louis, Missouri
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, Missouri
- Program in Quantitative Molecular Therapeutics, Washington University, St. Louis, Missouri
- Siteman Cancer Center, Washington University, St. Louis, Missouri
| | - Abhinav K Jha
- Department of Biomedical Engineering, Washington University, St. Louis, Missouri;
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, Missouri
- Siteman Cancer Center, Washington University, St. Louis, Missouri
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Epstein L, Heger G, Roy A, Gannot I, Kelson I, Arazi L. The low-LET radiation contribution to the tumor dose in diffusing alpha-emitters radiation therapy. Med Phys 2024; 51:3020-3033. [PMID: 38096442 DOI: 10.1002/mp.16885] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 11/16/2023] [Accepted: 11/21/2023] [Indexed: 04/05/2024] Open
Abstract
BACKGROUND Diffusing alpha-emitters Radiation Therapy ("Alpha DaRT") is a new technique that enables the use of alpha particles for the treatment of solid tumors. Alpha DaRT employs interstitial sources carrying a few μ $\mu$ Ci of224 $^{224}$ Ra below their surface, designed to release a chain of short-lived atoms (progeny of224 $^{224}$ Ra) which emit alpha particles, along with beta, Auger, and conversion electrons, x- and gamma rays. These atoms diffuse around the source and create-primarily through their alpha decays-a lethal high-dose region measuring a few millimeters in diameter. PURPOSE While previous studies focused on the dose from the alpha emissions alone, this work addresses the electron and photon dose contributed by the diffusing atoms and by the atoms remaining on the source surface, for both a single Alpha DaRT source and multi-source lattices. This allows to evaluate the low-LET contribution to the tumor dose and tumor cell survival, and demonstrate the sparing of surrounding healthy tissue. METHODS The low-LET dose is calculated using the EGSnrc and FLUKA Monte Carlo (MC) codes. We compare the results of a simple line-source approximation with no diffusion to those of a full simulation, which implements a realistic source geometry and the spread of diffusing atoms. We consider two opposite scenarios: one with low diffusion and high212 $^{212}$ Pb leakage, and the other with high diffusion and low leakage. The low-LET dose in source lattices is calculated by superposition of single-source contributions. Its effect on cell survival is estimated with the linear quadratic model in the limit of low dose rate. RESULTS For sources carrying 3 μ $\umu$ Ci/cm224 $^{224}$ Ra arranged in a hexagonal lattice with 4 mm spacing, the minimal low-LET dose between sources is∼ 18 - 30 $\sim 18-30$ Gy for the two test cases and is dominated by the beta contribution. The low-LET dose drops below 5 Gy∼ 3 $\sim 3$ mm away from the outermost source in the lattice with an effective maximal dose rate of< 0.04 $<0.04$ Gy/h. The accuracy of the line-source/no-diffusion approximation is∼ 15 % $\sim 15\%$ for the total low-LET dose over clinically relevant distances (2-4 mm). The low-LET dose reduces tumor cell survival by a factor of∼ 2 - 200 $\sim 2-200$ . CONCLUSIONS The low-LET dose in Alpha DaRT can be modeled by conventional MC techniques with appropriate leakage corrections to the source activity. For 3 μ $\umu$ Ci/cm224 $^{224}$ Ra sources, the contribution of the low-LET dose can reduce cell survival inside the tumor by up to two orders of magnitude. The low-LET dose to surrounding healthy tissue is negligible. Increasing source activities by a factor of 5 can bring the low-LET dose itself to therapeutic levels, in addition to the high-LET dose contributed by alpha particles, leading to a "self-boosted" Alpha DaRT configuration, and potentially allowing to increase the lattice spacing.
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Affiliation(s)
- Lior Epstein
- Unit of Nuclear Engineering, Faculty of Engineering Sciences, Ben-Gurion University of the Negev, Be'er-Sheva, Israel
- Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv, Israel
- Soreq Nuclear Research Center, Yavne, Israel
| | - Guy Heger
- Unit of Nuclear Engineering, Faculty of Engineering Sciences, Ben-Gurion University of the Negev, Be'er-Sheva, Israel
| | - Arindam Roy
- Unit of Nuclear Engineering, Faculty of Engineering Sciences, Ben-Gurion University of the Negev, Be'er-Sheva, Israel
| | - Israel Gannot
- Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv, Israel
| | - Itzhak Kelson
- School of Physics and Astronomy, Faculty of Exact Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Lior Arazi
- Unit of Nuclear Engineering, Faculty of Engineering Sciences, Ben-Gurion University of the Negev, Be'er-Sheva, Israel
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Heger G, Dumančić M, Luz I, Vatarescu M, Weizman N, Miller BW, Cooks T, Arazi L. First measurements of radon-220 diffusion in mice tumors, towards treatment planning in diffusing alpha-emitters radiation therapy. Med Phys 2024. [PMID: 38507254 DOI: 10.1002/mp.17020] [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: 09/01/2023] [Revised: 01/22/2024] [Accepted: 02/21/2024] [Indexed: 03/22/2024] Open
Abstract
BACKGROUND Diffusing alpha-emitters radiation therapy ("Alpha-DaRT") is a new method for treating solid tumors with alpha particles, relying on the release of the short-lived alpha-emitting daughter atoms of radium-224 from interstitial sources inserted into the tumor. Alpha-DaRT tumor dosimetry is governed by the spread of radium's progeny around the source, as described by an approximate framework called the "diffusion-leakage model". The most important model parameters are the diffusion lengths of radon-220 and lead-212, and their estimation is therefore essential for treatment planning. PURPOSE Previous works have provided initial estimates for the dominant diffusion length, by measuring the activity spread inside mice-borne tumors several days after the insertion of an Alpha-DaRT source. The measurements, taken when lead-212 was in secular equilibrium with radium-224, were interpreted as representing the lead-212 diffusion length. The aim of this work is to provide first experimental estimates for the diffusion length of radon-220, using a new methodology. METHODS The diffusion length of radon-220 was estimated from autoradiography measurements of histological sections taken from 24 mice-borne subcutaneous tumors of five different types. Unlike previous studies, the source dwell time inside the tumor was limited to 30 min, to prevent the buildup of lead-212. To investigate the contribution of potential non-diffusive processes, experiments were done in two sets: fourteen in vivo tumors, where during the treatment the tumors were still carried by the mice with active blood supply, and 10 ex-vivo tumors, where the tumors were excised before source insertion and kept in a medium at37 ∘ C $37^\circ {\text{C}}$ with the source inside. RESULTS The measured diffusion lengths of radon-220, extracted by fitting the recorded activity pattern up to 1.5 mm from the source, lie in the range0.25 - 0.6 mm ${0.25-0.6}\nobreakspace {\text{mm}}$ , with no significant difference between the average values measured in in-vivo and ex-vivo tumors:L R n i n - v i v o = 0.40 ± 0.08 mm $L_{Rn}^{in-vivo}=0.40{\pm }0.08\nobreakspace {\text{mm}}$ versusL R n e x - v i v o = 0.39 ± 0.07 mm $L_{Rn}^{ex-vivo}=0.39{\pm }0.07\nobreakspace {\text{mm}}$ . However, in-vivo tumors display an enhanced spread of activity 2-3 mm away from the source. This effect is not explained by the current model and is much less pronounced in ex-vivo tumors. CONCLUSIONS The average measured radon-220 diffusion lengths in both in-vivo and ex-vivo tumors are consistent with published data on the diffusion length of radon in water and lie close to the upper limit of the previously estimated range of0.2 - 0.4 mm $0.2-0.4\nobreakspace {\text{mm}}$ . The observation that close to the source there is no apparent difference between in-vivo and ex-vivo tumors, and the good agreement with the theoretical model in this region suggest that the spread of radon-220 is predominantly diffusive in this region. The departure from the model prediction in in-vivo tumors at large radial distances may hint at potential vascular contribution, which will be the subject of future works.
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Affiliation(s)
- Guy Heger
- Unit of Nuclear Engineering, Faculty of Engineering Sciences, Ben-Gurion University of the Negev, Beersheba, Israel
| | - Mirta Dumančić
- Unit of Nuclear Engineering, Faculty of Engineering Sciences, Ben-Gurion University of the Negev, Beersheba, Israel
- Now at Gerald Bronfman Department of Oncology, Faculty of Medicine and Health Sciences, McGill University, Montreal, Quebec, Canada
| | - Ishai Luz
- The Shraga Segal Department of Microbiology, Immunology, and Genetics, Ben-Gurion University of the Negev, Beersheba, Israel
| | - Maayan Vatarescu
- The Shraga Segal Department of Microbiology, Immunology, and Genetics, Ben-Gurion University of the Negev, Beersheba, Israel
| | - Noam Weizman
- Unit of Nuclear Engineering, Faculty of Engineering Sciences, Ben-Gurion University of the Negev, Beersheba, Israel
- Oncology Department, Radiation Therapy Unit, Hadassah - Hebrew University Medical Center, Jerusalem, Israel
| | - Brian W Miller
- College of Medicine, Department of Radiation Oncology, Department of Medical Imaging, The University of Arizona, Tucson, Arizona, USA
| | - Tomer Cooks
- The Shraga Segal Department of Microbiology, Immunology, and Genetics, Ben-Gurion University of the Negev, Beersheba, Israel
| | - Lior Arazi
- Unit of Nuclear Engineering, Faculty of Engineering Sciences, Ben-Gurion University of the Negev, Beersheba, Israel
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Jiang Z, Yang F, Wang W. Applications of Yttrium-90 ( 90Y) in Hepatocellular Carcinoma. Onco Targets Ther 2024; 17:149-157. [PMID: 38414759 PMCID: PMC10898254 DOI: 10.2147/ott.s445898] [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: 11/06/2023] [Accepted: 02/17/2024] [Indexed: 02/29/2024] Open
Abstract
Hepatocellular carcinoma (HCC) is the most common primary liver cancer, affecting millions of people worldwide. Due to the lack of systemic radiation therapy in hepatocellular carcinoma, researchers have been investigating the use of yttrium-90 (90Y) radioembolization for local-regional tumor control since the 1960s. With the development of glass and resin 90Y microspheres and the durable local control, good long-term efficacy, and equivalent tumor responsiveness and tolerability of 90Y-selective internal irradiation compared with alternative therapies such as transarterial chemoembolization (TACE) and sorafenib, 90Y radioembolization has gradually been applied in the treatment of hepatocellular carcinoma of all stages. In this article, we summarize the latest progress of 90Y in the treatment of hepatocellular carcinoma in terms of its principle, advantages, indications, contraindications, efficacy and adverse effects.
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Affiliation(s)
- ZhongHao Jiang
- Inner Mongolia Medical University, Department of Hepatobiliary Surgery, Affiliated Hospital of Inner Mongolia Medical University, Inner Mongolia, 010050, People’s Republic of China
| | - Fan Yang
- Inner Mongolia Medical University, Department of Hepatobiliary Surgery, Affiliated Hospital of Inner Mongolia Medical University, Inner Mongolia, 010050, People’s Republic of China
| | - WanXiang Wang
- Inner Mongolia Medical University, Department of Hepatobiliary Surgery, Affiliated Hospital of Inner Mongolia Medical University, Inner Mongolia, 010050, People’s Republic of China
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11
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Hooijman EL, Radchenko V, Ling SW, Konijnenberg M, Brabander T, Koolen SLW, de Blois E. Implementing Ac-225 labelled radiopharmaceuticals: practical considerations and (pre-)clinical perspectives. EJNMMI Radiopharm Chem 2024; 9:9. [PMID: 38319526 PMCID: PMC10847084 DOI: 10.1186/s41181-024-00239-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Accepted: 01/25/2024] [Indexed: 02/07/2024] Open
Abstract
BACKGROUND In the past years, there has been a notable increase in interest regarding targeted alpha therapy using Ac-225, driven by the observed promising clinical anti-tumor effects. As the production and technology has advanced, the availability of Ac-225 is expected to increase in the near future, making the treatment available to patients worldwide. MAIN BODY Ac-225 can be labelled to different biological vectors, whereby the success of developing a radiopharmaceutical depends heavily on the labelling conditions, purity of the radionuclide source, chelator, and type of quenchers used to avoid radiolysis. Multiple (methodological) challenges need to be overcome when working with Ac-225; as alpha-emission detection is time consuming and highly geometry dependent, a gamma co-emission is used, but has to be in equilibrium with the mother-nuclide. Because of the high impact of alpha emitters in vivo it is highly recommended to cross-calibrate the Ac-225 measurements for used quality control (QC) techniques (radio-TLC, HPLC, HP-Ge detector, and gamma counter). More strict health physics regulations apply, as Ac-225 has a high toxicity, thereby limiting practical handling and quantities used for QC analysis. CONCLUSION This overview focuses specifically on the practical and methodological challenges when working with Ac-225 labelled radiopharmaceuticals, and underlines the required infrastructure and (detection) methods for the (pre-)clinical application.
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Affiliation(s)
- Eline L Hooijman
- Department of Radiology and Nuclear Medicine, Erasmus MC, 3015 CN, Rotterdam, The Netherlands
- Department of Hospital Pharmacy, Erasmus MC, 3015 CN, Rotterdam, The Netherlands
| | - Valery Radchenko
- Life Sciences Division, TRIUMF, Vancouver, BC, V6T 2A3, Canada
- Chemistry Department, University of British Columbia, Vancouver, BC, V6T 1Z1, Canada
| | - Sui Wai Ling
- Department of Radiology and Nuclear Medicine, Erasmus MC, 3015 CN, Rotterdam, The Netherlands
| | - Mark Konijnenberg
- Department of Radiology and Nuclear Medicine, Erasmus MC, 3015 CN, Rotterdam, The Netherlands
| | - Tessa Brabander
- Department of Radiology and Nuclear Medicine, Erasmus MC, 3015 CN, Rotterdam, The Netherlands
| | - Stijn L W Koolen
- Department of Radiology and Nuclear Medicine, Erasmus MC, 3015 CN, Rotterdam, The Netherlands
- Department of Hospital Pharmacy, Erasmus MC, 3015 CN, Rotterdam, The Netherlands
- Department of Medical Oncology, Erasmus MC Cancer Institute, 3015 CN, Rotterdam, The Netherlands
| | - Erik de Blois
- Department of Radiology and Nuclear Medicine, Erasmus MC, 3015 CN, Rotterdam, The Netherlands.
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Sudo H, Tsuji AB, Sugyo A, Harada Y, Nagayama S, Katagiri T, Nakamura Y, Higashi T. Head-to-head comparison of three chelates reveals DOTAGA promising for 225 Ac labeling of anti-FZD10 antibody OTSA101. Cancer Sci 2023; 114:4677-4690. [PMID: 37781962 PMCID: PMC10728013 DOI: 10.1111/cas.15978] [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: 05/11/2023] [Revised: 09/04/2023] [Accepted: 09/12/2023] [Indexed: 10/03/2023] Open
Abstract
To select the most suitable chelate for 225 Ac radiolabeling of the anti-FZD10 antibody OTSA101, we directly compared three chelates: S-2-(4-isothiocyanatobenzyl)-1,4,7,10-tetraazacyclododecane tetraacetic acid (p-SCN-Bn-DOTA), 2,2',2″-(10-(1-carboxy-4-((4-isothiocyanatobenzyl)amino)-4-oxobutyl)-1,4,7,10-tetraazacyclododecane-1,4,7-triyl) triacetic acid (p-SCN-Bn-DOTAGA), and 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid mono-N-hydroxysuccinimide ester (DO3A-NHS-ester). We evaluated the binding affinity of the chelate-conjugated OTSA101 antibodies, as well as the labeling efficiency and stability in murine serum of 225 Ac-labeled OTSA101 as in vitro properties. The biodistribution, intratumoral distribution, absorbed doses, and therapeutic effects of the chelate-conjugated OTSA101 antibodies were assessed in the synovial sarcoma mouse model SYO-1. Of the three conjugates, DOTAGA conjugation had the smallest impact on the binding affinity (p < 0.01). The labeling efficiencies of DOTAGA-OTSA101 and DO3A-OTSA101 were 1.8-fold higher than that of DOTA-OTSA101 (p < 0.01). The stabilities were similar between 225 Ac-labeled DOTA-OTSA101, DOTAGA-OTSA101, and DO3A-OTSA101in serum at 37 and 4°C. The dosimetric analysis based on the biodistribution revealed significantly higher tumor-absorbed doses by 225 Ac-labeled DOTA-OTSA101 and DOTAGA-OTSA101 compared with 225 Ac-DO3A-OTSA101 (p < 0.05). 225 Ac-DOTAGA-OTSA101 exhibited the highest tumor-to-bone marrow ratio, with bone marrow being the dose-limiting tissue. The therapeutic and adverse effects were not significantly different between the three conjugates. Our findings indicate that among the three evaluated chelates, DOTAGA appears to be the most promising chelate to produce 225 Ac-labeled OTSA101 with high binding affinity and high radiochemical yields while providing high absorbed doses to tumors and limited absorbed doses to bone marrow.
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Affiliation(s)
- Hitomi Sudo
- Department of Molecular Imaging and TheranosticsNational Institutes for Quantum Science and Technology (QST)ChibaJapan
| | - Atsushi B. Tsuji
- Department of Molecular Imaging and TheranosticsNational Institutes for Quantum Science and Technology (QST)ChibaJapan
| | - Aya Sugyo
- Department of Molecular Imaging and TheranosticsNational Institutes for Quantum Science and Technology (QST)ChibaJapan
| | | | | | - Toyomasa Katagiri
- Division of Genome MedicineInstitute of Advanced Medical Sciences, Tokushima UniversityTokushimaJapan
- National Institutes of Biomedical Innovation, Health and NutritionIbarakiJapan
| | - Yusuke Nakamura
- National Institutes of Biomedical Innovation, Health and NutritionIbarakiJapan
| | - Tatsuya Higashi
- Department of Molecular Imaging and TheranosticsNational Institutes for Quantum Science and Technology (QST)ChibaJapan
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Zaid NRR, Kletting P, Beer AJ, Stallons TAR, Torgue JJ, Glatting G. Mathematical Modeling of In Vivo Alpha Particle Generators and Chelator Stability. Cancer Biother Radiopharm 2023; 38:528-535. [PMID: 33481653 DOI: 10.1089/cbr.2020.4112] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Background: Targeted α particle therapy using long-lived in vivo α particle generators is cytotoxic to target tissues. However, the redistribution of released radioactive daughters through the circulation should be considered. A mathematical model was developed to describe the physicochemical kinetics of 212Pb-labeled pharmaceuticals and its radioactive daughters. Materials and Methods: A bolus of 212Pb-labeled pharmaceuticals injected in a developed compartmental model was simulated. The contributions of chelated and free radionuclides to the total released energy were investigated for different dissociation fractions of 212Bi for different chelators, for example, 36% for DOTA. The compartmental model was applied to describe a 212Bi retention study and to assess the stability of the 212Bi-1,4,7,10-tetrakis(carbamoylmethyl)-1,4,7,10-tetraazacyclododecane (212Bi-DOTAM) complex after β- decay of 212Pb. Results: The simulation of the injection showed that α emissions contribute 75% to the total released energy, mostly from 212Po (72%). The simulation of the 212Bi retention study showed that (16 ± 5)% of 212Bi atoms dissociate from the 212Bi-DOTAM complexes. The fractions of energies released by free radionuclides were 21% and 38% for DOTAM and DOTA chelators, respectively. Conclusion: The developed α particle generator model allows for simulating the radioactive kinetics of labeled and unlabeled pharmaceuticals being released from the chelating system due to a preceding disintegration.
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Affiliation(s)
- Nouran R R Zaid
- Medical Radiation Physics, Department of Nuclear Medicine, Ulm University, Ulm, Germany
- Department of Biomedical Sciences, Biophysics and Medical Imaging Program, Faculty of Medicine and Health Sciences, An-Najah National University, Nablus, Palestine
| | - Peter Kletting
- Medical Radiation Physics, Department of Nuclear Medicine, Ulm University, Ulm, Germany
- Department of Nuclear Medicine, Ulm University, Ulm, Germany
| | - Ambros J Beer
- Department of Nuclear Medicine, Ulm University, Ulm, Germany
| | | | | | - Gerhard Glatting
- Medical Radiation Physics, Department of Nuclear Medicine, Ulm University, Ulm, Germany
- Department of Nuclear Medicine, Ulm University, Ulm, Germany
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14
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Dumontet C, Reichert JM, Senter PD, Lambert JM, Beck A. Antibody-drug conjugates come of age in oncology. Nat Rev Drug Discov 2023; 22:641-661. [PMID: 37308581 DOI: 10.1038/s41573-023-00709-2] [Citation(s) in RCA: 100] [Impact Index Per Article: 100.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/20/2023] [Indexed: 06/14/2023]
Abstract
Antibody-drug conjugates (ADCs) combine the specificity of monoclonal antibodies with the potency of highly cytotoxic agents, potentially reducing the severity of side effects by preferentially targeting their payload to the tumour site. ADCs are being increasingly used in combination with other agents, including as first-line cancer therapies. As the technology to produce these complex therapeutics has matured, many more ADCs have been approved or are in late-phase clinical trials. The diversification of antigenic targets as well as bioactive payloads is rapidly broadening the scope of tumour indications for ADCs. Moreover, novel vector protein formats as well as warheads targeting the tumour microenvironment are expected to improve the intratumour distribution or activation of ADCs, and consequently their anticancer activity for difficult-to-treat tumour types. However, toxicity remains a key issue in the development of these agents, and better understanding and management of ADC-related toxicities will be essential for further optimization. This Review provides a broad overview of the recent advances and challenges in ADC development for cancer treatment.
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Affiliation(s)
- Charles Dumontet
- CRCL INSERM 1052/CNRS 5286, University of Lyon, Hospices Civils de Lyon, Lyon, France.
| | | | | | | | - Alain Beck
- Institut de Recherche Pierre Fabre, CIPF, Saint-Julien-en-Genevois, France
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Patell K, Kurian M, Garcia JA, Mendiratta P, Barata PC, Jia AY, Spratt DE, Brown JR. Lutetium-177 PSMA for the treatment of metastatic castrate resistant prostate cancer: a systematic review. Expert Rev Anticancer Ther 2023; 23:731-744. [PMID: 37194261 DOI: 10.1080/14737140.2023.2213892] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Accepted: 05/10/2023] [Indexed: 05/18/2023]
Abstract
INTRODUCTION Metastatic castrate resistant prostate cancer (mCPRC) remains an aggressive form of prostate cancer that no longer responds to traditional hormonal treatment alone. Despite the advent of novel anti-androgen medications, many patients continue to progress, and as a result, there is a growing need for additional treatment options. AREAS COVERED Lutetium-177 (177Lu) - PSMA-617 has become one of the new frontline treatment options for refractory metastatic castrate resistant prostate cancer after the failure of novel anti-androgen therapy and chemotherapy. Lu-177 has been used in real-world prospective trials and is now becoming utilized in newer phase III clinical trials. Here, we present a comprehensive overview of the current literature, covering retrospective studies, prospective studies, and clinical trials that established Lutetium-177-PSMA-617 (177Lu-PSMA-617) for the treatment of mCRPC. EXPERT OPINION 177Lu - PSMA-617 has been approved for treatment of mCRPC based on positive phase III studies. While this treatment is tolerable and effective, biomarkers are necessary to determine which patients will benefit. In the future, radioligand treatments will likely be utilized in earlier lines of therapy and potentially in combination with other prostate cancer treatments.
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Affiliation(s)
- Kanchi Patell
- Deparment of Internal Medicine, Division of Medical Oncology, University Hospitals Seidman Cancer Center, Cleveland, OH, USA
| | - Matthew Kurian
- Deparment of Internal Medicine, Division of Medical Oncology, University Hospitals Seidman Cancer Center, Cleveland, OH, USA
| | - Jorge A Garcia
- Deparment of Internal Medicine, Division of Medical Oncology, University Hospitals Seidman Cancer Center, Cleveland, OH, USA
- Case Comprehensive Cancer Center, Cleveland, OH, USA
| | - Prateek Mendiratta
- Deparment of Internal Medicine, Division of Medical Oncology, University Hospitals Seidman Cancer Center, Cleveland, OH, USA
- Case Comprehensive Cancer Center, Cleveland, OH, USA
| | - Pedro C Barata
- Deparment of Internal Medicine, Division of Medical Oncology, University Hospitals Seidman Cancer Center, Cleveland, OH, USA
- Case Comprehensive Cancer Center, Cleveland, OH, USA
| | - Angela Y Jia
- Department of Radiation Oncology, University Hospitals Seidman Cancer Center, Cleveland, OH, USA
- Case Comprehensive Cancer Center, Cleveland, OH, USA
| | - Daniel E Spratt
- Department of Radiation Oncology, University Hospitals Seidman Cancer Center, Cleveland, OH, USA
- Case Comprehensive Cancer Center, Cleveland, OH, USA
| | - Jason R Brown
- Deparment of Internal Medicine, Division of Medical Oncology, University Hospitals Seidman Cancer Center, Cleveland, OH, USA
- Case Comprehensive Cancer Center, Cleveland, OH, USA
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16
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Handula M, Beekman S, Konijnenberg M, Stuurman D, de Ridder C, Bruchertseifer F, Morgenstern A, Denkova A, de Blois E, Seimbille Y. First preclinical evaluation of [ 225Ac]Ac-DOTA-JR11 and comparison with [ 177Lu]Lu-DOTA-JR11, alpha versus beta radionuclide therapy of NETs. EJNMMI Radiopharm Chem 2023; 8:13. [PMID: 37389800 DOI: 10.1186/s41181-023-00197-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Accepted: 06/02/2023] [Indexed: 07/01/2023] Open
Abstract
BACKGROUND The [177Lu]Lu-DOTA-TATE mediated peptide receptor radionuclide therapy (PRRT) of neuroendocrine tumors (NETs) is sometimes leading to treatment resistance and disease recurrence. An interesting alternative could be the somatostatin antagonist, [177Lu]Lu-DOTA-JR11, that demonstrated better biodistribution profile and higher tumor uptake than [177Lu]Lu-DOTA-TATE. Furthermore, treatment with alpha emitters showed improvement of the therapeutic index of PRRT due to the high LET offered by the alpha particles compared to beta emitters. Therefore, [225Ac]Ac-DOTA-JR11 can be a potential candidate to improve the treatment of NETs (Graphical abstract). DOTA-JR11 was radiolabeled with [225Ac]Ac(NO3)3 and [177Lu]LuCl3. Stability studies were performed in phosphate buffered saline (PBS) and mouse serum. In vitro competitive binding assay has been carried out in U2OS-SSTR2 + cells for natLa-DOTA-JR11, natLu-DOTA-JR11 and DOTA-JR11. Ex vivo biodistribution studies were performed in mice inoculated with H69 cells at 4, 24, 48 and 72 h after injection of [225Ac]Ac-DOTA-JR11. A blocking group was included to verify uptake specificity. Dosimetry of selected organs was determined for [225Ac]Ac-DOTA-JR11 and [177Lu]Lu-DOTA-JR11. RESULTS [225Ac]Ac-DOTA-JR11 has been successfully prepared and obtained in high radiochemical yield (RCY; 95%) and radiochemical purity (RCP; 94%). [225Ac]Ac-DOTA-JR11 showed reasonably good stability in PBS (77% intact radiopeptide at 24 h after incubation) and in mouse serum (~ 81% intact radiopeptide 24 h after incubation). [177Lu]Lu-DOTA-JR11 demonstrated excellent stability in both media (> 93%) up to 24 h post incubation. Competitive binding assay revealed that complexation of DOTA-JR11 with natLa and natLu did not affect its binding affinity to SSTR2. Similar biodistribution profiles were observed for both radiopeptides, however, higher uptake was noticed in the kidneys, liver and bone for [225Ac]Ac-DOTA-JR11 than [177Lu]Lu-DOTA-JR11. CONCLUSION [225Ac]Ac-DOTA-JR11 showed a higher absorbed dose in the kidneys compared to [177Lu]Lu-DOTA-JR11, which may limit further studies with this radiopeptide. However, several strategies can be explored to reduce nephrotoxicity and offer opportunities for future clinical investigations with [225Ac]Ac-DOTA-JR11.
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Affiliation(s)
- Maryana Handula
- Department of Radiology and Nuclear Medicine, Erasmus MC Cancer Institute, Erasmus University Medical Center, 3015 GD, Rotterdam, The Netherlands
| | - Savanne Beekman
- Department of Radiology and Nuclear Medicine, Erasmus MC Cancer Institute, Erasmus University Medical Center, 3015 GD, Rotterdam, The Netherlands
| | - Mark Konijnenberg
- Department of Radiology and Nuclear Medicine, Erasmus MC Cancer Institute, Erasmus University Medical Center, 3015 GD, Rotterdam, The Netherlands
| | - Debra Stuurman
- Department of Radiology and Nuclear Medicine, Erasmus MC Cancer Institute, Erasmus University Medical Center, 3015 GD, Rotterdam, The Netherlands
- Department of Experimental Urology, Erasmus University Medical Center, 3015 GD, Rotterdam, The Netherlands
| | - Corrina de Ridder
- Department of Radiology and Nuclear Medicine, Erasmus MC Cancer Institute, Erasmus University Medical Center, 3015 GD, Rotterdam, The Netherlands
- Department of Experimental Urology, Erasmus University Medical Center, 3015 GD, Rotterdam, The Netherlands
| | | | | | - Antonia Denkova
- Applied Radiation and Isotopes, Department of Radiation Science and Technology, Faculty of Applied Sciences, Delft University of Technology, Delft, The Netherlands
| | - Erik de Blois
- Department of Radiology and Nuclear Medicine, Erasmus MC Cancer Institute, Erasmus University Medical Center, 3015 GD, Rotterdam, The Netherlands
| | - Yann Seimbille
- Department of Radiology and Nuclear Medicine, Erasmus MC Cancer Institute, Erasmus University Medical Center, 3015 GD, Rotterdam, The Netherlands.
- Life Sciences Division, TRIUMF, Vancouver, BC, V6T 2A3, Canada.
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Rahman MA, Li Z, Yu Z, Laforest R, Thorek DLJ, Jha AK. A list-mode multi-energy window low-count SPECT reconstruction method for isotopes with multiple emission peaks. EJNMMI Phys 2023; 10:40. [PMID: 37347319 PMCID: PMC10287621 DOI: 10.1186/s40658-023-00558-3] [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: 01/05/2023] [Accepted: 05/31/2023] [Indexed: 06/23/2023] Open
Abstract
BACKGROUND Single-photon emission computed tomography (SPECT) provides a mechanism to perform absorbed-dose quantification tasks for [Formula: see text]-particle radiopharmaceutical therapies ([Formula: see text]-RPTs). However, quantitative SPECT for [Formula: see text]-RPT is challenging due to the low number of detected counts, the complex emission spectrum, and other image-degrading artifacts. Towards addressing these challenges, we propose a low-count quantitative SPECT reconstruction method for isotopes with multiple emission peaks. METHODS Given the low-count setting, it is important that the reconstruction method extracts the maximal possible information from each detected photon. Processing data over multiple energy windows and in list-mode (LM) format provide mechanisms to achieve that objective. Towards this goal, we propose a list-mode multi energy window (LM-MEW) ordered-subsets expectation-maximization-based SPECT reconstruction method that uses data from multiple energy windows in LM format and include the energy attribute of each detected photon. For computational efficiency, we developed a multi-GPU-based implementation of this method. The method was evaluated using 2-D SPECT simulation studies in a single-scatter setting conducted in the context of imaging [[Formula: see text]Ra]RaCl[Formula: see text], an FDA-approved RPT for metastatic prostate cancer. RESULTS The proposed method yielded improved performance on the task of estimating activity uptake within known regions of interest in comparison to approaches that use a single energy window or use binned data. The improved performance was observed in terms of both accuracy and precision and for different sizes of the region of interest. CONCLUSIONS Results of our studies show that the use of multiple energy windows and processing data in LM format with the proposed LM-MEW method led to improved quantification performance in low-count SPECT of isotopes with multiple emission peaks. These results motivate further development and validation of the LM-MEW method for such imaging applications, including for [Formula: see text]-RPT SPECT.
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Affiliation(s)
- Md Ashequr Rahman
- Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, USA
- Mallinckrodt Institute of Radiology, Washington University in St. Louis, St. Louis, USA
| | - Zekun Li
- Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, USA
- Mallinckrodt Institute of Radiology, Washington University in St. Louis, St. Louis, USA
| | - Zitong Yu
- Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, USA
- Mallinckrodt Institute of Radiology, Washington University in St. Louis, St. Louis, USA
| | - Richard Laforest
- Mallinckrodt Institute of Radiology, Washington University in St. Louis, St. Louis, USA
| | - Daniel L. J. Thorek
- Mallinckrodt Institute of Radiology, Washington University in St. Louis, St. Louis, USA
| | - Abhinav K. Jha
- Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, USA
- Mallinckrodt Institute of Radiology, Washington University in St. Louis, St. Louis, USA
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Bidkar AP, Wang S, Bobba KN, Chan E, Bidlingmaier S, Egusa EA, Peter R, Ali U, Meher N, Wadhwa A, Dhrona S, Dasari C, Beckford-Vera D, Su Y, Tang R, Zhang L, He J, Wilson DM, Aggarwal R, VanBrocklin HF, Seo Y, Chou J, Liu B, Flavell RR. Treatment of Prostate Cancer with CD46-targeted 225Ac Alpha Particle Radioimmunotherapy. Clin Cancer Res 2023; 29:1916-1928. [PMID: 36917693 PMCID: PMC10183825 DOI: 10.1158/1078-0432.ccr-22-3291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 01/19/2023] [Accepted: 03/10/2023] [Indexed: 03/15/2023]
Abstract
PURPOSE Radiopharmaceutical therapy is changing the standard of care in prostate cancer and other malignancies. We previously reported high CD46 expression in prostate cancer and developed an antibody-drug conjugate and immunoPET agent based on the YS5 antibody, which targets a tumor-selective CD46 epitope. Here, we present the preparation, preclinical efficacy, and toxicity evaluation of [225Ac]DOTA-YS5, a radioimmunotherapy agent based on the YS5 antibody. EXPERIMENTAL DESIGN [225Ac]DOTA-YS5 was developed, and its therapeutic efficiency was tested on cell-derived (22Rv1, DU145), and patient-derived (LTL-545, LTL484) prostate cancer xenograft models. Biodistribution studies were carried out on 22Rv1 tumor xenograft models to confirm the targeting efficacy. Toxicity analysis of the [225Ac]DOTA-YS5 was carried out on nu/nu mice to study short-term (acute) and long-term (chronic) toxicity. RESULTS Biodistribution study shows that [225Ac]DOTA-YS5 agent delivers high levels of radiation to the tumor tissue (11.64% ± 1.37%ID/g, 28.58% ± 10.88%ID/g, 29.35% ± 7.76%ID/g, and 31.78% ± 5.89%ID/g at 24, 96, 168, and 408 hours, respectively), compared with the healthy organs. [225Ac]DOTA-YS5 suppressed tumor size and prolonged survival in cell line-derived and patient-derived xenograft models. Toxicity analysis revealed that the 0.5 μCi activity levels showed toxicity to the kidneys, likely due to redistribution of daughter isotope 213Bi. CONCLUSIONS [225Ac]DOTA-YS5 suppressed the growth of cell-derived and patient-derived xenografts, including prostate-specific membrane antigen-positive and prostate-specific membrane antigen-deficient models. Overall, this preclinical study confirms that [225Ac]DOTA-YS5 is a highly effective treatment and suggests feasibility for clinical translation of CD46-targeted radioligand therapy in prostate cancer.
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Affiliation(s)
- Anil P. Bidkar
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, California
| | - Sinan Wang
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, California
| | - Kondapa Naidu Bobba
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, California
| | - Emily Chan
- Department of Pathology, University of California, San Francisco, California
| | - Scott Bidlingmaier
- Department of Anesthesia, University of California, San Francisco, San Francisco, California
| | - Emily A. Egusa
- Division of Hematology/Oncology, Department of Medicine, University of California, San Francisco, California
- UCSF Helen Diller Family Comprehensive Cancer Center, San Francisco, California
| | - Robin Peter
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, California
- Department of Nuclear Engineering, University of California, Berkeley, California
| | - Umama Ali
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, California
| | - Niranjan Meher
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, California
| | - Anju Wadhwa
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, California
| | - Suchi Dhrona
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, California
| | - Chandrashekhar Dasari
- Department of Surgery, Cardiovascular Research Institute, University of California San Francisco, San Francisco, California
| | - Denis Beckford-Vera
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, California
| | - Yang Su
- Department of Anesthesia, University of California, San Francisco, San Francisco, California
| | - Ryan Tang
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, California
| | - Li Zhang
- Department of Medicine and the Department of Epidemiology and Biostatistics, University of California, Berkeley, California
| | - Jiang He
- Department of Radiology and Medical Imaging, University of Virginia, Charlottesville, Virginia
| | - David M. Wilson
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, California
- UCSF Helen Diller Family Comprehensive Cancer Center, San Francisco, California
| | - Rahul Aggarwal
- Division of Hematology/Oncology, Department of Medicine, University of California, San Francisco, California
- UCSF Helen Diller Family Comprehensive Cancer Center, San Francisco, California
| | - Henry F. VanBrocklin
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, California
| | - Youngho Seo
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, California
- UCSF Helen Diller Family Comprehensive Cancer Center, San Francisco, California
| | - Jonathan Chou
- Division of Hematology/Oncology, Department of Medicine, University of California, San Francisco, California
- UCSF Helen Diller Family Comprehensive Cancer Center, San Francisco, California
| | - Bin Liu
- Department of Anesthesia, University of California, San Francisco, San Francisco, California
- UCSF Helen Diller Family Comprehensive Cancer Center, San Francisco, California
| | - Robert R. Flavell
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, California
- UCSF Helen Diller Family Comprehensive Cancer Center, San Francisco, California
- Department of Pharmaceutical Chemistry, University of California, San Francisco, California
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Kauffman N, Singh SK, Morrison J, Zinn KR. Effective therapy with Bismuth-212 labeled macroaggregated albumin in orthotopic mouse breast tumor models. Front Chem 2023; 11:1204872. [PMID: 37234203 PMCID: PMC10206259 DOI: 10.3389/fchem.2023.1204872] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Accepted: 05/02/2023] [Indexed: 05/27/2023] Open
Abstract
Intravascularly administered radiation therapy using beta (β-)-emitting radioisotopes has relied on either intravenously injected radiolabeled peptides that target cancer or radiolabeled microspheres that are trapped in the tumor following intra-arterial delivery. More recently, targeted intravenous radiopeptide therapies have explored the use of alpha (α)-particle emitting radioisotopes, but microspheres radiolabeled with α-particle emitters have not yet been studied. Here, FDA-approved macroaggregated albumin (MAA) particles were radiolabeled with Bismuth-212 (Bi-212-MAA) and evaluated using clonogenic and survival assays in vitro and using immune-competent mouse models of breast cancer. The in vivo biodistribution of Bi-212-MAA was investigated in Balb/c and C57BL/6 mice with 4T1 and EO771 orthotopic breast tumors, respectively. The same orthotopic breast cancer models were used to evaluate the treatment efficacy of Bi-212-MAA. Our results showed that macroaggregated albumin can be stably radiolabeled with Bi-212 and that Bi-212-MAA can deliver significant radiation therapy to reduce the growth and clonogenic potential of 4T1 and EO771 cells in vitro. Additionally, Bi-212-MAA treatment upregulated γH2AX and cleaved Caspase-3 expression in 4T1 cells. Biodistribution analyses showed 87-93% of the Bi-212-MAA remained in 4T1 and EO771 tumors 2 and 4 h after injection. Following single-tumor treatments with Bi-212-MAA there was a significant reduction in the growth of both 4T1 and EO771 breast tumors over the 18-day monitoring period. Overall, these findings showed that Bi-212-MAA was stably radiolabeled and inhibited breast cancer growth. Bi-212-MAA is an exciting platform to study α-particle therapy and will be easily translatable to larger animal models and human clinical trials.
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Affiliation(s)
- Nathan Kauffman
- Comparative Medicine and Integrative Biology, Institute for Quantitative Health Science and Engineering, Michigan State University, East Lansing, MI, United States
| | - Satyendra Kumar Singh
- Department of Biomedical Engineering, Institute for Quantitative Health Science and Engineering, Michigan State University, East Lansing, MI, United States
| | - James Morrison
- Advanced Radiology Services, Grand Rapids, MI, United States
| | - Kurt R. Zinn
- Departments of Radiology, Biomedical Engineering, Small Animal Clinical Sciences, Institute for Quantitative Health Science and Engineering, Michigan State University, East Lansing, MI, United States
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20
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Kauffman N, Morrison J, O’Brien K, Fan J, Zinn KR. Intra-Arterial Delivery of Radiopharmaceuticals in Oncology: Current Trends and the Future of Alpha-Particle Therapeutics. Pharmaceutics 2023; 15:pharmaceutics15041138. [PMID: 37111624 PMCID: PMC10144492 DOI: 10.3390/pharmaceutics15041138] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 03/29/2023] [Accepted: 03/30/2023] [Indexed: 04/07/2023] Open
Abstract
A paradigm shift is underway in cancer diagnosis and therapy using radioactivity-based agents called radiopharmaceuticals. In the new strategy, diagnostic imaging measures the tumor uptake of radioactive agent “X” in a patient’s specific cancer, and if uptake metrics are realized, the patient can be selected for therapy with radioactive agent “Y”. The X and Y represent different radioisotopes that are optimized for each application. X–Y pairs are known as radiotheranostics, with the currently approved route of therapy being intravenous administration. The field is now evaluating the potential of intra-arterial dosing of radiotheranostics. In this manner, a higher initial concentration can be achieved at the cancer site, which could potentially enhance tumor-to-background targeting and lead to improved imaging and therapy. Numerous clinical trials are underway to evaluate these new therapeutic approaches that can be performed via interventional radiology. Of further interest is changing the therapeutic radioisotope that provides radiation therapy by β- emission to radioisotopes that also decay by α-particle emissions. Alpha (α)-particle emissions provide high energy transfer to the tumors and have distinct advantages. This review discusses the current landscape of intra-arterially delivered radiopharmaceuticals and the future of α-particle therapy with short-lived radioisotopes.
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Affiliation(s)
- Nathan Kauffman
- Comparative Medicine and Integrative Biology, Institute for Quantitative Health Science and Engineering, Michigan State University, East Lansing, MI 48824, USA
| | - James Morrison
- Advanced Radiology Services, 3264 N Evergreen Dr, Grand Rapids, MI 49525, USA
| | - Kevin O’Brien
- Department of Radiology, Henry Ford Health System, Detroit, MI 48202, USA
| | - Jinda Fan
- Departments of Radiology and Chemistry, Institute for Quantitative Health Science and Engineering, Michigan State University, East Lansing, MI 48824, USA
| | - Kurt R. Zinn
- Departments of Radiology, Biomedical Engineering, Small Animal Clinical Sciences, Institute for Quantitative Health Science and Engineering, Michigan State University, East Lansing, MI 48824, USA
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21
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Satapathy S, Chandekar KR, Bal C. Gastro-Enteric-Pancreatic Neuroendocrine Tumor Treatment: Actinium-225-DOTATATE and Combined Therapies. PET Clin 2023; 18:215-221. [PMID: 36858746 DOI: 10.1016/j.cpet.2022.11.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/03/2023]
Abstract
The role of lutetium-177-DOTATATE in advanced well-differentiated gastro-entero-pancreatic neuroendocrine tumors is well established. However, there is a scope for improving treatment outcomes. Actinium-225-DOTATATE is a form of targeted alpha therapy (TAT) that results in more efficient tumor cell killing owing to the substantially higher linear energy transfer of alpha particles. Systemic TAT is also safe given that the shorter path length of the alpha particles spares the surrounding healthy tissue and results in relatively fewer adverse events. Combination therapies with radiosensitizing and other chemotherapeutic agents have also gained popularity, especially in the setting of higher grade and fluorodeoxyglucose-avid tumors.
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Affiliation(s)
- Swayamjeet Satapathy
- Department of Nuclear Medicine, All India Institute of Medical Sciences, Ansari Nagar, New Delhi 110029, India
| | - Kunal Ramesh Chandekar
- Department of Nuclear Medicine, All India Institute of Medical Sciences, Ansari Nagar, New Delhi 110029, India
| | - Chandrasekhar Bal
- Department of Nuclear Medicine, All India Institute of Medical Sciences, Ansari Nagar, New Delhi 110029, India.
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22
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Liatsou I, Josefsson A, Yu J, Cortez A, Bastiaannet R, Velarde E, Davis K, Brayton C, Wang H, Torgue J, Hobbs RF, Sgouros G. Bone Marrow Relative Biological Effectiveness for a 212Pb-labeled Anti-HER2/neu Antibody. Int J Radiat Oncol Biol Phys 2023; 115:518-528. [PMID: 35926719 DOI: 10.1016/j.ijrobp.2022.07.1842] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Revised: 07/25/2022] [Accepted: 07/28/2022] [Indexed: 01/11/2023]
Abstract
PURPOSE We have determined the in vivo relative biological effectiveness (RBE) of an alpha-particle-emitting radiopharmaceutical therapeutic agent (212Pb-labeled anti-HER2/neu antibody) for the bone marrow, a potentially dose-limiting normal tissue. METHODS AND MATERIALS The RBE was measured in mice using femur marrow cellularity as the biological endpoint. External beam radiation therapy (EBRT), delivered by a small-animal radiation research platform was used as the reference radiation. Alpha-particle emissions were delivered by 212Bi after the decay of its parent nuclide 212Pb, which was conjugated onto an anti-HER2/neu antibody. The alpha-particle absorbed dose to the marrow after an intravenous administration (tail vein) of 122.1 to 921.3 kBq 212Pb-TCMC-7.16.4 was calculated. The mice were sacrificed at 0 to 7 days after treatment and the radioactivity from the femur bone marrow was measured. Changes in marrow cellularity were assessed by histopathology. RESULTS The dose response for EBRT and 212Pb-anti-HER2/neu antibody were linear-quadratic and linear, respectively. On transforming the EBRT dose-response relationship into a linear relationship using the equivalent dose in 2-Gy fractions of external beam radiation formalism, we obtained an RBE (denoted RBE2) of 6.4, which is independent of cellularity and absorbed dose. CONCLUSIONS Because hematologic toxicity is dose limiting in almost all antibody-based RPT, in vivo measurements of RBE are important in helping identify an initial administered activity in phase 1 escalation trials. Applying the RBE2 and assuming typical antibody clearance kinetics (biological half-life of 48 hours), using a modified blood-based dosimetry method, an average administered activity of approximately 185.5 MBq (5.0 mCi) per patient could be administered before hematologic toxicity is anticipated.
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Affiliation(s)
- Ioanna Liatsou
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland.
| | - Anders Josefsson
- Department of Radiology, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Jing Yu
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Angel Cortez
- Department of Radiology, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Remco Bastiaannet
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Esteban Velarde
- Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Kaori Davis
- Department of Molecular and Comparative Pathobiology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Cory Brayton
- Department of Molecular and Comparative Pathobiology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Hao Wang
- Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | | | - Robert F Hobbs
- Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - George Sgouros
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland
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23
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The sodium iodide symporter (NIS) as theranostic gene: potential role in pre-clinical therapy of extra-thyroidal malignancies. Clin Transl Imaging 2023. [DOI: 10.1007/s40336-023-00540-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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24
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Karlsson J, Schatz CA, Wengner AM, Hammer S, Scholz A, Cuthbertson A, Wagner V, Hennekes H, Jardine V, Hagemann UB. Targeted thorium-227 conjugates as treatment options in oncology. Front Med (Lausanne) 2023; 9:1071086. [PMID: 36726355 PMCID: PMC9885765 DOI: 10.3389/fmed.2022.1071086] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2022] [Accepted: 12/15/2022] [Indexed: 01/10/2023] Open
Abstract
Targeted alpha therapy (TAT) is a promising approach for addressing unmet needs in oncology. Inherent properties make α-emitting radionuclides well suited to cancer therapy, including high linear energy transfer (LET), penetration range of 2-10 cell layers, induction of complex double-stranded DNA breaks, and immune-stimulatory effects. Several alpha radionuclides, including radium-223 (223Ra), actinium-225 (225Ac), and thorium-227 (227Th), have been investigated. Conjugation of tumor targeting modalities, such as antibodies and small molecules, with a chelator moiety and subsequent radiolabeling with α-emitters enables specific delivery of cytotoxic payloads to different tumor types. 223Ra dichloride, approved for the treatment of patients with metastatic castration-resistant prostate cancer (mCRPC) with bone-metastatic disease and no visceral metastasis, is the only approved and commercialized alpha therapy. However, 223Ra dichloride cannot currently be complexed to targeting moieties. In contrast to 223Ra, 227Th may be readily chelated, which allows radiolabeling of tumor targeting moieties to produce targeted thorium conjugates (TTCs), facilitating delivery to a broad range of tumors. TTCs have shown promise in pre-clinical studies across a range of tumor-cell expressing antigens. A clinical study in hematological malignancy targeting CD22 has demonstrated early signs of activity. Furthermore, pre-clinical studies show additive or synergistic effects when TTCs are combined with established anti-cancer therapies, for example androgen receptor inhibitors (ARI), DNA damage response inhibitors such as poly (ADP)-ribose polymerase inhibitors or ataxia telangiectasia and Rad3-related kinase inhibitors, as well as immune checkpoint inhibitors.
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25
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Li Z, Benabdallah N, Abou DS, Baumann BC, Dehdashti F, Ballard DH, Liu J, Jammalamadaka U, Laforest R, Wahl RL, Thorek DLJ, Jha AK. A Projection-Domain Low-Count Quantitative SPECT Method for α-Particle-Emitting Radiopharmaceutical Therapy. IEEE TRANSACTIONS ON RADIATION AND PLASMA MEDICAL SCIENCES 2023; 7:62-74. [PMID: 37201111 PMCID: PMC10191330 DOI: 10.1109/trpms.2022.3175435] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2023]
Abstract
Single-photon emission-computed tomography (SPECT) provides a mechanism to estimate regional isotope uptake in lesions and at-risk organs after administration of α-particle-emitting radiopharmaceutical therapies (α-RPTs). However, this estimation task is challenging due to the complex emission spectra, the very low number of detected counts (~20 times lower than in conventional SPECT), the impact of stray-radiation-related noise at these low counts, and the multiple image-degrading processes in SPECT. The conventional reconstruction-based quantification methods are observed to be erroneous for α-RPT SPECT. To address these challenges, we developed a low-count quantitative SPECT (LC-QSPECT) method that directly estimates the regional activity uptake from the projection data (obviating the reconstruction step), compensates for stray-radiation-related noise, and accounts for the radioisotope and SPECT physics, including the isotope spectra, scatter, attenuation, and collimator-detector response, using a Monte Carlo-based approach. The method was validated in the context of 3-D SPECT with 223Ra, a commonly used radionuclide for α-RPT. Validation was performed using both realistic simulation studies, including a virtual clinical trial, and synthetic and 3-D-printed anthropomorphic physical-phantom studies. Across all studies, the LC-QSPECT method yielded reliable regional-uptake estimates and outperformed the conventional ordered subset expectation-maximization (OSEM)-based reconstruction and geometric transfer matrix (GTM)-based post-reconstruction partial-volume compensation methods. Furthermore, the method yielded reliable uptake across different lesion sizes, contrasts, and different levels of intralesion heterogeneity. Additionally, the variance of the estimated uptake approached the Cramér-Rao bound-defined theoretical limit. In conclusion, the proposed LC-QSPECT method demonstrated the ability to perform reliable quantification for α-RPT SPECT.
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Affiliation(s)
- Zekun Li
- Department of Biomedical Engineering, Washington University, St. Louis, MO 63130 USA
| | - Nadia Benabdallah
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, MO 63110 USA
| | - Diane S Abou
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, MO 63110 USA
| | - Brian C Baumann
- Department of Radiation Oncology, Washington University, St. Louis, MO 63110 USA
| | - Farrokh Dehdashti
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, MO 63110 USA
| | - David H Ballard
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, MO 63110 USA
| | - Jonathan Liu
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, MO 63110 USA
| | - Uday Jammalamadaka
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, MO 63110 USA
| | - Richard Laforest
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, MO 63110 USA
| | - Richard L Wahl
- Mallinckrodt Institute of Radiology, Washington University, St. Louis, MO 63110 USA
| | - Daniel L J Thorek
- Department of Biomedical Engineering, the Mallinckrodt Institute of Radiology, and the Program in Quantitative Molecular Therapeutics, Washington University, St. Louis, MO 63110 USA
| | - Abhinav K Jha
- Department of Biomedical Engineering and the Mallinckrodt Institute of Radiology, Washington University, St. Louis, MO 63130 USA
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TSUJI S, IMAI K. Medical application of the monoclonal antibody SKM9-2 against sialylated HEG1, a new precision marker for malignant mesothelioma. PROCEEDINGS OF THE JAPAN ACADEMY. SERIES B, PHYSICAL AND BIOLOGICAL SCIENCES 2023; 99:39-47. [PMID: 36775341 PMCID: PMC10020423 DOI: 10.2183/pjab.99.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Accepted: 11/28/2022] [Indexed: 06/18/2023]
Abstract
Malignant pleural mesothelioma (MPM) is an aggressive tumor of the pleural cavity. Pathologically distinguishing MPM from other pleural lesions is often difficult. We searched for marker antigens to facilitate the pathological diagnosis of MPM and found useful markers for the pathological detection of malignant mesothelioma. Among them, the anti-mesothelioma monoclonal antibody SKM9-2, which was isolated as a clone binding to specimens of MPM (but not to specimens of lung adenocarcinoma) by immunohistochemical screening, showed higher specificity and sensitivity than traditional mesothelioma markers. SKM9-2 recognizes both sialylated O-glycans and peptide sequences in HEG1, and its glycan modifications are specific to mesothelioma. New effective treatments for MPM are needed because the prognosis of patients with MPM is usually poor. SKM9-2 can be used as a seed for next-generation antibody drugs with strong cytotoxic activities. In this review, we have summarized our research on antibody development for MPM diagnosis and treatment.
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Affiliation(s)
- Shoutaro TSUJI
- Department of Medical Technology & Clinical Engineering, Gunma University of Health and Welfare, Maebashi, Gunma, Japan
| | - Kohzoh IMAI
- Institute for Genetic Medicine, Hokkaido University, Sapporo, Hokkaido, Japan
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27
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Shi M, Jakobsson V, Greifenstein L, Khong PL, Chen X, Baum RP, Zhang J. Alpha-peptide receptor radionuclide therapy using actinium-225 labeled somatostatin receptor agonists and antagonists. Front Med (Lausanne) 2022; 9:1034315. [PMID: 36569154 PMCID: PMC9767967 DOI: 10.3389/fmed.2022.1034315] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Accepted: 11/21/2022] [Indexed: 12/12/2022] Open
Abstract
Peptide receptor radionuclide therapy (PRRT) has over the last two decades emerged as a very promising approach to treat neuroendocrine tumors (NETs) with rapidly expanding clinical applications. By chelating a radiometal to a somatostatin receptor (SSTR) ligand, radiation can be delivered to cancer cells with high precision. Unlike conventional external beam radiotherapy, PRRT utilizes primarily β or α radiation derived from nuclear decay, which causes damage to cancer cells in the immediate proximity by irreversible direct or indirect ionization of the cells' DNA, which induces apoptosis. In addition, to avoid damage to surrounding normal cells, PRRT privileges the use of radionuclides that have little penetrating and more energetic (and thus more ionizing) radiations. To date, the most frequently radioisotopes are β- emitters, particularly Yttrium-90 (90Y) and Lutetium-177 (177Lu), labeled SSTR agonists. Current development of SSTR-targeting is triggering the shift from using SSTR agonists to antagonists for PRRT. Furthermore, targeted α-particle therapy (TAT), has attracted special attention for the treatment of tumors and offers an improved therapeutic option for patients resistant to conventional treatments or even beta-irradiation treatment. Due to its short range and high linear energy transfer (LET), α-particles significantly damage the targeted cancer cells while causing minimal cytotoxicity toward surrounding normal tissue. Actinium-225 (225Ac) has been developed into potent targeting drug constructs including somatostatin-receptor-based radiopharmaceuticals and is in early clinical use against multiple neuroendocrine tumor types. In this article, we give a review of preclinical and clinical applications of 225Ac-PRRT in NETs, discuss the strengths and challenges of 225Ac complexes being used in PRRT; and envision the prospect of 225Ac-PRRT as a future alternative in the treatment of NETs.
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Affiliation(s)
- Mengqi Shi
- Department of Diagnostic Radiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore,Nanomedicine Translational Research Program, NUS Center for Nanomedicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Vivianne Jakobsson
- Department of Diagnostic Radiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore,Academy for Precision Oncology, International Centers for Precision Oncology (ICPO), Wiesbaden, Germany
| | - Lukas Greifenstein
- CURANOSTICUM Wiesbaden-Frankfurt, Center for Advanced Radiomolecular Precision Oncology, Wiesbaden, Germany
| | - Pek-Lan Khong
- Department of Diagnostic Radiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore,Clinical Imaging Research Centre, Centre for Translational Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Xiaoyuan Chen
- Department of Diagnostic Radiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore,Nanomedicine Translational Research Program, NUS Center for Nanomedicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore,Clinical Imaging Research Centre, Centre for Translational Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore,Department of Surgery, Chemical and Biomolecular Engineering, and Biomedical Engineering, Yong Loo Lin School of Medicine and College of Design and Engineering, National University of Singapore, Singapore, Singapore,Agency for Science, Technology, and Research (A*STAR), Institute of Molecular and Cell Biology, Singapore, Singapore
| | - Richard P. Baum
- CURANOSTICUM Wiesbaden-Frankfurt, Center for Advanced Radiomolecular Precision Oncology, Wiesbaden, Germany
| | - Jingjing Zhang
- Department of Diagnostic Radiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore,Nanomedicine Translational Research Program, NUS Center for Nanomedicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore,Clinical Imaging Research Centre, Centre for Translational Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore,*Correspondence: Jingjing Zhang,
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28
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ICRP PUBLICATION 153 Approved by the Commission in September 2022. Ann ICRP 2022; 51:9-95. [PMID: 36942865 DOI: 10.1177/01466453221142702] [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] [Indexed: 03/23/2023]
Abstract
Veterinary use of radiation in the diagnosis, management, and treatment of disease has expanded and diversified, as have the corresponding radiological protection concerns. Radiological exposure of personnel involved in veterinary procedures and, where applicable, members of the public providing assistance (e.g. owners or handlers) has always been included within the system of radiological protection. Veterinary practice is now addressed explicitly as the modern complexities associated with this practice warrant dedicated consideration, and there is a need to clarify and strengthen the application of radiological protection principles in this area. The Commission recommends that the system of radiological protection should be applied in veterinary practice principally for the protection of humans, but with explicit attention to the protection of exposed animals. Additionally, consideration should be given to the risk of potential contamination of the environment associated with applications of nuclear medicine in veterinary practice. This publication focuses primarily on justification and optimisation in veterinary practice, and sets the scene for more detailed guidance to follow in future Recommendations. It is intended for a wide-ranging audience, including radiological protection professionals, veterinary staff, students, education and training providers, and members of the public, as an introduction to radiological protection in veterinary practice.© 2022 ICRP. Published by SAGE.
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Theoretical Study of Complexes of Tetravalent Actinides with DOTA. Symmetry (Basel) 2022. [DOI: 10.3390/sym14112451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
1,4,7,10-Tetraazacyclododecane-N,N′,N″,N‴-tetraacetic acid (H4DOTA) is a prominent chelating ligand with potential applications in various fields, from radiotherapy to the separation of fission products. The present study explores the stability, structure, and bonding properties of its complexes with tetravalent actinides (An = Th, U, Np, Pu) using density functional theory and relativistic multireference calculations. Neutral complexes prefer to form symmetric (C4) structures with DOTA. The first coordination sphere of the actinide ions is readily saturated by a weakly bonded H2O ligand. The latter ligand reduces the molecular symmetry while exerting only marginal effects on the properties of the parent complex. An-ligand bonding is mainly electrostatic, but there are also significant charge-transfer contributions from DOTA to the An 6d/5f orbitals. The charge-transfer interactions and the covalent character of bonding increase gradually in the order of Th < U < Np < Pu, as indicated by analysis of the electron density distribution using the Quantum Theory of Atoms in Molecules.
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Caravaca J, Huh Y, Gullberg GT, Seo Y. Compton and proximity imaging of 225Ac in vivo with a CZT gamma camera: a proof of principle with simulations. IEEE TRANSACTIONS ON RADIATION AND PLASMA MEDICAL SCIENCES 2022; 6:904-915. [PMID: 36338821 PMCID: PMC9632644 DOI: 10.1109/trpms.2022.3166116] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
In vivo imaging of 225Ac is a major challenge in the development of targeted alpha therapy radiopharmaceuticals due to the extremely low injected doses. In this paper, we present the design of a multi-modality gamma camera that integrates both proximity and Compton imaging in order to achieve the demanding sensitivities required to image 225Ac with good image quality. We consider a dual-head camera, each of the heads consisting of two planar cadmium zinc telluride detectors acting as scatterer and absorber for Compton imaging, and with the scatterer practically in contact with the subject to allow for proximity imaging. We optimize the detector's design and characterize the detector's performance using Monte Carlo simulations. We show that Compton imaging can resolve features of up to 1.5 mm for hot rod phantoms with an activity of 1 μCi, and can reconstruct 3D images of a mouse injected with 0.5 μCi after a 15 minutes exposure and with a single bed position, for both 221Fr and 213Bi. Proximity imaging is able to resolve two 1 mm-radius sources of less than 0.1 μCi separated by 1 cm and at 1 mm from the detector, as well as it can provide planar images of 221Fr and 213Bi biodistributions of the mouse phantom in 5 minutes.
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Affiliation(s)
- Javier Caravaca
- Department of Radiology and Biomedical Imaging of the University of California San Francisco in San Francisco (CA) USA
| | - Yoonsuk Huh
- Department of Radiology and Biomedical Imaging of the University of California San Francisco in San Francisco (CA) USA
| | - Grant T Gullberg
- Department of Radiology and Biomedical Imaging of the University of California San Francisco in San Francisco (CA) USA
| | - Youngho Seo
- Department of Radiology and Biomedical Imaging of the University of California San Francisco in San Francisco (CA) USA
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Nishri Y, Vatarescu M, Luz I, Epstein L, Dumančić M, Del Mare S, Shai A, Schmidt M, Deutsch L, Den RB, Kelson I, Keisari Y, Arazi L, Cooks T, Domankevich V. Diffusing alpha-emitters radiation therapy in combination with temozolomide or bevacizumab in human glioblastoma multiforme xenografts. Front Oncol 2022; 12:888100. [PMID: 36237307 PMCID: PMC9552201 DOI: 10.3389/fonc.2022.888100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Accepted: 09/02/2022] [Indexed: 11/13/2022] Open
Abstract
Glioblastoma multiforme (GBM) is at present an incurable disease with a 5-year survival rate of 5.5%, despite improvements in treatment modalities such as surgery, radiation therapy, chemotherapy [e.g., temozolomide (TMZ)], and targeted therapy [e.g., the antiangiogenic agent bevacizumab (BEV)]. Diffusing alpha-emitters radiation therapy (DaRT) is a new modality that employs radium-224-loaded seeds that disperse alpha-emitting atoms inside the tumor. This treatment was shown to be effective in mice bearing human-derived GBM tumors. Here, the effect of DaRT in combination with standard-of-care therapies such as TMZ or BEV was investigated. In a viability assay, the combination of alpha radiation with TMZ doubled the cytotoxic effect of each of the treatments alone in U87 cultured cells. A colony formation assay demonstrated that the surviving fraction of U87 cells treated by TMZ in combination with alpha irradiation was lower than was achieved by alpha- or x-ray irradiation as monotherapies, or by x-ray combined with TMZ. The treatment of U87-bearing mice with DaRT and TMZ delayed tumor development more than the monotherapies. Unlike other radiation types, alpha radiation did not increase VEGF secretion from U87 cells in culture. BEV treatment introduced several days after DaRT implantation improved tumor control, compared to BEV or DaRT as monotherapies. The combination was also shown to be superior when starting BEV administration prior to DaRT implantation in large tumors relative to the seed size. BEV induced a decrease in CD31 staining under DaRT treatment, increased the diffusive spread of 224Ra progeny atoms in the tumor tissue, and decreased their clearance from the tumor through the blood. Taken together, the combinations of DaRT with standard-of-care chemotherapy or antiangiogenic therapy are promising approaches, which may improve the treatment of GBM patients.
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Affiliation(s)
- Yossi Nishri
- Translational Research Laboratory, Alpha Tau Medical, Jerusalem, Israel
| | - Maayan Vatarescu
- Translational Research Laboratory, Alpha Tau Medical, Jerusalem, Israel
- The Shraga Segal Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University, Beer-Sheva, Israel
| | - Ishai Luz
- Translational Research Laboratory, Alpha Tau Medical, Jerusalem, Israel
- The Shraga Segal Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University, Beer-Sheva, Israel
| | - Lior Epstein
- Unit of Nuclear Engineering, Faculty of Engineering Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
- Radiation Protection Department, Soreq Nuclear Research Center, Yavne, Israel
- Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv, Israel
| | - Mirta Dumančić
- Unit of Nuclear Engineering, Faculty of Engineering Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Sara Del Mare
- Translational Research Laboratory, Alpha Tau Medical, Jerusalem, Israel
| | - Amit Shai
- Translational Research Laboratory, Alpha Tau Medical, Jerusalem, Israel
| | | | - Lisa Deutsch
- Biostatistics Department, BioStats Statistical Consulting Ltd., Maccabim, Israel
| | - Robert B. Den
- Translational Research Laboratory, Alpha Tau Medical, Jerusalem, Israel
- Department of Radiation Oncology, Urology, and Cancer Biology, Thomas Jefferson University, Philadelphia, PA, United States
| | - Itzhak Kelson
- School of Physics and Astronomy, Raymond and Beverly Sackler Faculty of Exact Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Yona Keisari
- Department of Clinical Microbiology and Immunology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Lior Arazi
- Unit of Nuclear Engineering, Faculty of Engineering Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
- *Correspondence: Lior Arazi, ; Tomer Cooks, ; Vered Domankevich,
| | - Tomer Cooks
- The Shraga Segal Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University, Beer-Sheva, Israel
- *Correspondence: Lior Arazi, ; Tomer Cooks, ; Vered Domankevich,
| | - Vered Domankevich
- Translational Research Laboratory, Alpha Tau Medical, Jerusalem, Israel
- *Correspondence: Lior Arazi, ; Tomer Cooks, ; Vered Domankevich,
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Batra V, Samanta M, Makvandi M, Groff D, Martorano P, Elias J, Ranieri P, Tsang M, Hou C, Li Y, Pawel B, Martinez D, Vaidyanathan G, Carlin S, Pryma DA, Maris JM. Preclinical Development of [211At]meta- astatobenzylguanidine ([211At]MABG) as an Alpha Particle Radiopharmaceutical Therapy for Neuroblastoma. Clin Cancer Res 2022; 28:4146-4157. [PMID: 35861867 PMCID: PMC9475242 DOI: 10.1158/1078-0432.ccr-22-0400] [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: 03/09/2022] [Revised: 06/09/2022] [Accepted: 07/19/2022] [Indexed: 01/07/2023]
Abstract
PURPOSE [131I]meta-iodobenzylguanidine ([131I]MIBG) is a targeted radiotherapeutic administered systemically to deliver beta particle radiation in neuroblastoma. However, relapses in the bone marrow are common. [211At]meta-astatobenzylguanidine ([211At] MABG) is an alpha particle emitter with higher biological effectiveness and short path length which effectively sterilizes microscopic residual disease. Here we investigated the safety and antitumor activity [211At]MABG in preclinical models of neuroblastoma. EXPERIMENTAL DESIGN We defined the maximum tolerated dose (MTD), biodistribution, and toxicity of [211At]MABG in immunodeficient mice in comparison with [131I]MIBG. We compared the antitumor efficacy of [211At]MABG with [131I]MIBG in three murine xenograft models. Finally, we explored the efficacy of [211At]MABG after tail vein xenografting designed to model disseminated neuroblastoma. RESULTS The MTD of [211At]MABG was 66.7 MBq/kg (1.8 mCi/kg) in CB17SC scid-/- mice and 51.8 MBq/kg (1.4 mCi/kg) in NOD.Cg-Prkdcscid Il2rgtm1Wjl/SzJ (NSG) mice. Biodistribution of [211At]MABG was similar to [131I]MIBG. Long-term toxicity studies on mice administered with doses up to 41.5 MBq/kg (1.12 mCi/kg) showed the radiotherapeutic to be well tolerated. Both 66.7 MBq/kg (1.8 mCi/kg) single dose and fractionated dosing 16.6 MBq/kg/fraction (0.45 mCi/kg) × 4 over 11 days induced marked tumor regression in two of the three models studied. Survival was significantly prolonged for mice treated with 12.9 MBq/kg/fraction (0.35 mCi/kg) × 4 doses over 11 days [211At]MABG in the disseminated disease (IMR-05NET/GFP/LUC) model (P = 0.003) suggesting eradication of microscopic disease. CONCLUSIONS [211At]MABG has significant survival advantage in disseminated models of neuroblastoma. An alpha particle emitting radiopharmaceutical may be effective against microscopic disseminated disease, warranting clinical development.
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Affiliation(s)
- Vandana Batra
- Division of Oncology and Center for Childhood Cancer Research, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania.,Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Minu Samanta
- Division of Oncology and Center for Childhood Cancer Research, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Mehran Makvandi
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania
| | - David Groff
- Division of Oncology and Center for Childhood Cancer Research, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Paul Martorano
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Jimmy Elias
- Division of Oncology and Center for Childhood Cancer Research, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Pietro Ranieri
- Division of Oncology and Center for Childhood Cancer Research, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Matthew Tsang
- Division of Oncology and Center for Childhood Cancer Research, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Catherine Hou
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Yimei Li
- Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania.,Department of Biostatistics, Epidemiology, and Informatics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Bruce Pawel
- Department of Pathology and Laboratory Medicine, Children's Hospital Los Angeles and Keck School of Medicine, University of Southern California, Los Angeles, California
| | - Daniel Martinez
- Division of Anatomic Pathology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | | | - Sean Carlin
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Daniel A. Pryma
- Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania.,Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania
| | - John M. Maris
- Division of Oncology and Center for Childhood Cancer Research, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania.,Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania.,Corresponding Author: John M. Maris, Division of Oncology and Center for Childhood Cancer Research, Children's Hospital of Philadelphia, 3501 Civic Center Boulevard, Philadelphia, PA 19104. Phone: 215-590-5242; E-mail:
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Damulira E. Radiation dosimetry in medicine using II-VI semiconductors. JOURNAL OF RADIATION RESEARCH AND APPLIED SCIENCES 2022. [DOI: 10.1016/j.jrras.2022.06.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Wang Y, Zhang Z, Sun W, Zhang J, Xu Q, Zhou X, Mao L. Ferroptosis in colorectal cancer: Potential mechanisms and effective therapeutic targets. Biomed Pharmacother 2022; 153:113524. [DOI: 10.1016/j.biopha.2022.113524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2022] [Revised: 08/03/2022] [Accepted: 08/08/2022] [Indexed: 01/17/2023] Open
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Li JJ, Xia XP, Wu LM, Zhu Z, Shi YN, Zhang XC, Xia YS, Lu GR. Cancer suppression by ferroptosis and its role in digestive system tumors. Shijie Huaren Xiaohua Zazhi 2022; 30:718-728. [DOI: 10.11569/wcjd.v30.i16.718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Cancer is the second leading cause of death worldwide, and digestive system tumors remain the leading malignancy in China, seriously endangering national health and imposing a huge economic burden. Ferroptosis is a form of cell death characterized by increased intracellular reduced iron and accumulated lipid peroxide. Recent studies have revealed that ferroptosis is closely related to the occurrence and treatment of cancer. Therefore, this paper reviews the studies on ferroptosis and cancer to explore the potential of ferroptosis in the treatment of malignant tumors, especially digestive system tumors, and to provide a new direction for developing treatment options.
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Affiliation(s)
- Jia-Jia Li
- Department of Gastroenterology, The Second Affiliated Hospital of Wenzhou Medical University, Wenzhou 325000, Zhejiang Province, China
| | - Xuan-Ping Xia
- Department of Gastroenterology, The Second Affiliated Hospital of Wenzhou Medical University, Wenzhou 325000, Zhejiang Province, China
| | - Li-Min Wu
- Department of Gastroenterology, The Second Affiliated Hospital of Wenzhou Medical University, Wenzhou 325000, Zhejiang Province, China
| | - Zheng Zhu
- The Second Clinical Medical College of Wenzhou Medical University, Wenzhou 325000, Zhejiang Province, China
| | - Yu-Ning Shi
- The Second Clinical Medical College of Wenzhou Medical University, Wenzhou 325000, Zhejiang Province, China
| | - Xu-Chao Zhang
- The Second Clinical Medical College of Wenzhou Medical University, Wenzhou 325000, Zhejiang Province, China
| | - Yu-Shan Xia
- The Second Clinical Medical College of Wenzhou Medical University, Wenzhou 325000, Zhejiang Province, China
| | - Guang-Rong Lu
- Department of Gastroenterology, The Second Affiliated Hospital of Wenzhou Medical University, Wenzhou 325000, Zhejiang Province, China
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Sporer E, Poulie CBM, Bäck T, Lindegren S, Jensen H, Kempen PJ, Kjaer A, Herth MM, Jensen AI. Covalent core-radiolabeling of polymeric micelles with 125I/ 211At for theranostic radiotherapy. Nanotheranostics 2022; 6:388-399. [PMID: 35912139 PMCID: PMC9330252 DOI: 10.7150/ntno.71906] [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: 02/14/2022] [Accepted: 07/07/2022] [Indexed: 11/05/2022] Open
Abstract
Astatine-211 (211At) is one of the most promising α-emitters for targeted alpha therapy, especially of cancer metastases. However, the lack of a stable isotope, frequent in vivo deastatination, and limited radiochemical knowledge makes it challenging to apply. Here, we report a new strategy for radiolabeling the lipophilic core of polymeric micelles (PMs) with covalently bound 211At. The PMs were radiolabeled via either an indirect synthon-based method or directly on the amphipathic block copolymer. The radiochemistry was optimized with iodine-125 (125I) and then adapted for 211At, enabling the use of both elements as a potential theranostic pair. PMs that were core-radiolabeled with both 125I or 211At were prepared and characterized, based on a PEG(5k)-PLGA(10k) co-polymer. The stability of the radiolabeled PMs was evaluated in mouse serum for 21 h, showing radiochemical stability above 85%. After in vivo evaluation of the 211At- labeled PMs, 4-5 % ID/g of the 211At could still be detected in the blood, showing a promising in vivo stability of the PMs. Further, 211At-labeled PMs accumulated in the spleen (20-30 %ID/g) and the liver (2.5- 5.5 %ID/g), along with some detection of 211At in the thyroid (3.5-9 %ID/g). This led to the hypothesis that deastatination takes place in the liver, whereas good stability of the 211At core-radiolabel was observed in the blood.
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Affiliation(s)
- Emanuel Sporer
- Center for Nanomedicine and Theranostics (The Hevesy Laboratory), DTU Health Technology, Technical University of Denmark (DTU), Ørsteds Plads 345C, 2800 Lyngby, Denmark
| | - Christian B M Poulie
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark
| | - Tom Bäck
- Departments of Radiation Physics, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gula Stråket 2b, 41345 Gothenburg, Sweden
| | - Sture Lindegren
- Departments of Radiation Physics, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gula Stråket 2b, 41345 Gothenburg, Sweden
| | - Holger Jensen
- Department of Clinical Physiology, Nuclear Medicine & PET, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen, Denmark
| | - Paul J Kempen
- Center for Nanomedicine and Theranostics (The Hevesy Laboratory), DTU Health Technology, Technical University of Denmark (DTU), Ørsteds Plads 345C, 2800 Lyngby, Denmark.,National Centre for Nano Fabrication and Characterization, Technical University of Denmark (DTU), Oersteds Plads-Building 347, 2800 Lyngby, Denmark
| | - Andreas Kjaer
- Department of Clinical Physiology, Nuclear Medicine & PET, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen, Denmark.,Cluster for Molecular Imaging, Department of Biomedical Sciences, University of Copenhagen, Blegdamsvej 3, 2100 Copenhagen, Denmark
| | - Matthias M Herth
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark.,Department of Clinical Physiology, Nuclear Medicine & PET, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen, Denmark
| | - Andreas I Jensen
- Center for Nanomedicine and Theranostics (The Hevesy Laboratory), DTU Health Technology, Technical University of Denmark (DTU), Ørsteds Plads 345C, 2800 Lyngby, Denmark
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Core-shell structured gold nanoparticles as carrier for 166Dy/ 166Ho in vivo generator. EJNMMI Radiopharm Chem 2022; 7:16. [PMID: 35852733 PMCID: PMC9296738 DOI: 10.1186/s41181-022-00170-3] [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: 06/01/2022] [Accepted: 07/04/2022] [Indexed: 12/24/2022] Open
Abstract
Background Radionuclide therapy (RNT) has become a very important treatment modality for cancer nowadays. Comparing with other cancer treatment options, sufficient efficacy could be achieved in RNT with lower toxicity. β− emitters are frequently used in RNT due to the long tissue penetration depth of the β− particles. The dysprosium-166/holmium-166 (166Dy/166Ho) in vivo generator shows great potential for treating large malignancies due to the long half-life time of the mother nuclide 166Dy and the emission of high energy β− from the daughter nuclide 166Ho. However, the internal conversion occurring after β− decay from 166Dy to 166Ho could cause the release of about 72% of 166Ho when 166Dy is bound to conventional chelators. The aim of this study is to develop a nanoparticle based carrier for 166Dy/166Ho in vivo generator such that the loss of the daughter nuclide 166Ho induced by internal conversion is prevented. To achieve this goal, we radiolabelled platinum-gold bimetallic nanoparticles (PtAuNPs) and core–shell structured gold nanoparticles (AuNPs) with 166Dy and studied the retention of both 166Dy and 166Ho under various conditions. Results The 166Dy was co-reduced with gold and platinum precursor to form the 166DyAu@AuNPs and 166DyPtAuNPs. The 166Dy radiolabelling efficiency was determined to be 60% and 70% for the two types of nanoparticles respectively. The retention of 166Dy and 166Ho were tested in MiliQ water or 2.5 mM DTPA for a period of 72 h. In both cases, more than 90% of both 166Dy and 166Ho was retained. The results show that the incorporation of 166Dy in AuNPs can prevent the escape of 166Ho released due to internal conversion. Conclusion We developed a chelator-free radiolabelling method for 166Dy with good radiolabelling efficiency and very high stability and retention of the daughter nuclide 166Ho. The results from this study indicate that to avoid the loss of the daughter radionuclides by internal conversion, carriers composed of electron-rich materials should be used. Supplementary Information The online version contains supplementary material available at 10.1186/s41181-022-00170-3.
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Kovács A. Theoretical Study of Heptadentate Bispidine Ligands for Radiopharmaceutic Applications. COMPUT THEOR CHEM 2022. [DOI: 10.1016/j.comptc.2022.113716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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225Ac-rHDL Nanoparticles: A Potential Agent for Targeted Alpha-Particle Therapy of Tumors Overexpressing SR-BI Proteins. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27072156. [PMID: 35408554 PMCID: PMC9000893 DOI: 10.3390/molecules27072156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 03/18/2022] [Accepted: 03/23/2022] [Indexed: 11/25/2022]
Abstract
Actinium-225 and other alpha-particle-emitting radionuclides have shown high potential for cancer treatment. Reconstituted high-density lipoproteins (rHDL) specifically recognize the scavenger receptor B type I (SR-BI) overexpressed in several types of cancer cells. Furthermore, after rHDL-SR-BI recognition, the rHDL content is injected into the cell cytoplasm. This research aimed to prepare a targeted 225Ac-delivering nanosystem by encapsulating the radionuclide into rHDL nanoparticles. The synthesis of rHDL was performed in two steps using the microfluidic synthesis method for the subsequent encapsulation of 225Ac, previously complexed to a lipophilic molecule (225Ac-DOTA-benzene-p-SCN, CLog P = 3.42). The nanosystem (13 nm particle size) showed a radiochemical purity higher than 99% and stability in human serum. In vitro studies in HEP-G2 and PC-3 cancer cells (SR-BI positive) demonstrated that 225Ac was successfully internalized into the cytoplasm of cells, delivering high radiation doses to cell nuclei (107 Gy to PC-3 and 161 Gy to HEP-G2 nuclei at 24 h), resulting in a significant decrease in cell viability down to 3.22 ± 0.72% for the PC-3 and to 1.79 ± 0.23% for HEP-G2 at 192 h after 225Ac-rHDL treatment. After intratumoral 225Ac-rHDL administration in mice bearing HEP-G2 tumors, the biokinetic profile showed significant retention of radioactivity in the tumor masses (90.16 ± 2.52% of the injected activity), which generated ablative radiation doses (649 Gy/MBq). The results demonstrated adequate properties of rHDL as a stable carrier for selective deposition of 225Ac within cancer cells overexpressing SR-BI. The results obtained in this research justify further preclinical studies, designed to evaluate the therapeutic efficacy of the 225Ac-rHDL system for targeted alpha-particle therapy of tumors that overexpress the SR-BI receptor.
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Kovács A. Metal-ligand bonding in bispidine chelate complexes for radiopharmaceutical applications. Struct Chem 2022. [DOI: 10.1007/s11224-022-01902-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
AbstractThe complexes of selected radionuclides relevant for nuclear medicine (InIII, BiIII, LuIII, AcIII and in addition LaIII for comparative purposes) with the octadentate (6,6′-((9-hydroxy-1,5-bis(methoxycarbonyl)-2,4-di(pyridin-2-yl)-3,7-diazabicyclo[3.3.1]nonane-3,7-diyl)bis(methylene))dipicolinic acid) ligand, H2bispa2, have been studied by density functional theory calculations modelling both isolated and aqueous solution conditions. The properties in focus are the encapsulation efficiency of the ligand for the different-size metals (M), the differences in bonding with the various MIII ions analysed using Bader’s atoms in molecules theory and the possibility and characteristics of nona- and decacoordination by H2O ligands. The computed results confirmed strong steric effects in the case of the In complex excluding higher than octacoordination. The studied properties depend strongly on the interplay of the sizes and electronic structures of the MIII ions. The computations support high stability of the complexes in aqueous solution, where also the solvation energies of the MIII ions (as dissociation products) play a significant role.
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Suzuki H, Kaneko MK, Kato Y. Roles of Podoplanin in Malignant Progression of Tumor. Cells 2022; 11:cells11030575. [PMID: 35159384 PMCID: PMC8834262 DOI: 10.3390/cells11030575] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Revised: 02/02/2022] [Accepted: 02/05/2022] [Indexed: 02/07/2023] Open
Abstract
Podoplanin (PDPN) is a cell-surface mucin-like glycoprotein that plays a critical role in tumor development and normal development of the lung, kidney, and lymphatic vascular systems. PDPN is overexpressed in several tumors and is involved in their malignancy. PDPN induces platelet aggregation through binding to platelet receptor C-type lectin-like receptor 2. Furthermore, PDPN modulates signal transductions that regulate cell proliferation, differentiation, migration, invasion, epithelial-to-mesenchymal transition, and stemness, all of which are crucial for the malignant progression of tumor. In the tumor microenvironment (TME), PDPN expression is upregulated in the tumor stroma, including cancer-associated fibroblasts (CAFs) and immune cells. CAFs play significant roles in the extracellular matrix remodeling and the development of immunosuppressive TME. Additionally, PDPN functions as a co-inhibitory molecule on T cells, indicating its involvement with immune evasion. In this review, we describe the mechanistic basis and diverse roles of PDPN in the malignant progression of tumors and discuss the possibility of the clinical application of PDPN-targeted cancer therapy, including cancer-specific monoclonal antibodies, and chimeric antigen receptor T technologies.
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Affiliation(s)
- Hiroyuki Suzuki
- Department of Molecular Pharmacology, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai 980-8575, Japan
- Correspondence: (H.S.); (Y.K.); Tel.: +81-22-717-8207 (H.S. & Y.K.)
| | - Mika K. Kaneko
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai 980-8575, Japan;
| | - Yukinari Kato
- Department of Molecular Pharmacology, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai 980-8575, Japan
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai 980-8575, Japan;
- Correspondence: (H.S.); (Y.K.); Tel.: +81-22-717-8207 (H.S. & Y.K.)
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Satapathy S, Sood A, Das CK, Kavanal AJ, Mittal BR. Alpha Before Beta: Exceptional Response to First-Line 225Ac-DOTATATE in a Patient of Metastatic Neuroendocrine Tumor With Extensive Skeletal Involvement. Clin Nucl Med 2022; 47:e156-e157. [PMID: 34284478 DOI: 10.1097/rlu.0000000000003823] [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
ABSTRACT The utility of β-emitter 177Lu-DOTATATE in patients of neuroendocrine tumors (NETs) with widespread skeletal metastases is limited by its relatively modest response rates and a significant concern for hematotoxicity. In such situations, targeted α therapy with 225Ac-DOTATATE can be potentially beneficial. In this report, a 46-year-old man with rectal NET and extensive skeletal metastases was treated upfront with 6 cycles of 225Ac-DOTATATE at 8 weeks' intervals. The patient showed excellent symptomatic, biochemical, and radiological response with no grade 3/4 adverse events. The first-line use of 225Ac-DOTATATE, therefore, presents a novel strategy for metastatic NETs with high skeletal disease burden.
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Affiliation(s)
| | | | - Chandan Krushna Das
- Medical Oncology, Regional Cancer Centre, Post Graduate Institute of Medical Education and Research, Chandigarh, India
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Wagstaff P, Gabiña PM, Mínguez R, Roeske JC. Alpha particle microdosimetry calculations using a shallow neural network. Phys Med Biol 2022; 67. [DOI: 10.1088/1361-6560/ac499c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Accepted: 01/10/2022] [Indexed: 11/12/2022]
Abstract
Abstract
A shallow neural network was trained to accurately calculate the microdosimetric parameters, 〈z
1〉 and 〈z
1
2〉 (the first and second moments of the single-event specific energy spectra, respectively) for use in alpha-particle microdosimetry calculations. The regression network of four inputs and two outputs was created in MATLAB and trained on a data set consisting of both previously published microdosimetric data and recent Monte Carlo simulations. The input data consisted of the alpha-particle energies (3.97–8.78 MeV), cell nuclei radii (2–10 μm), cell radii (2.5–20 μm), and eight different source-target configurations. These configurations included both single cells in suspension and cells in geometric clusters. The mean square error (MSE) was used to measure the performance of the network. The sizes of the hidden layers were chosen to minimize MSE without overfitting. The final neural network consisted of two hidden layers with 13 and 20 nodes, respectively, each with tangential sigmoid transfer functions, and was trained on 1932 data points. The overall training/validation resulted in a MSE = 3.71 × 10−7. A separate testing data set included input values that were not seen by the trained network. The final test on 892 separate data points resulted in a MSE = 2.80 × 10−7. The 95th percentile testing data errors were within ±1.4% for 〈z
1〉 outputs and ±2.8% for 〈z
1
2〉 outputs, respectively. Cell survival was also predicted using actual versus neural network generated microdosimetric moments and showed overall agreement within ±3.5%. In summary, this trained neural network can accurately produce microdosimetric parameters used for the study of alpha-particle emitters. The network can be exported and shared for tests on independent data sets and new calculations.
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Kip A, Heskamp S. Antibodies and antibody constructs as radiopharmaceuticals. Nucl Med Mol Imaging 2022. [DOI: 10.1016/b978-0-12-822960-6.00009-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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Sudo H, Tsuji AB, Sugyo A, Harada Y, Nagayama S, Katagiri T, Nakamura Y, Higashi T. FZD10-targeted α-radioimmunotherapy with 225 Ac-labeled OTSA101 achieves complete remission in a synovial sarcoma model. Cancer Sci 2021; 113:721-732. [PMID: 34935247 PMCID: PMC8819345 DOI: 10.1111/cas.15235] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 11/18/2021] [Accepted: 11/27/2021] [Indexed: 12/14/2022] Open
Abstract
Synovial sarcomas are rare tumors arising in adolescents and young adults. The prognosis for advanced disease is poor, with an overall survival of 12‐18 months. Frizzled homolog 10 (FZD10) is overexpressed in most synovial sarcomas, making it a promising therapeutic target. The results of a phase 1 trial of β‐radioimmunotherapy (RIT) with the 90Y‐labeled anti‐FZD10 antibody OTSA101 revealed a need for improved efficacy. The present study evaluated the potential of α‐RIT with OTSA101 labeled with the α‐emitter 225Ac. Competitive inhibition and cell binding assays showed that specific binding of 225Ac‐labeled OTSA101 to SYO‐1 synovial sarcoma cells was comparable to that of the imaging agent 111In‐labeled OTSA101. Biodistribution studies showed high uptake in SYO‐1 tumors and low uptake in normal organs, except for blood. Dosimetric studies showed that the biologically effective dose (BED) of 225Ac‐labeled OTSA101 for tumors was 7.8 Bd higher than that of 90Y‐labeled OTSA101. 90Y‐ and 225Ac‐labeled OTSA101 decreased tumor volume and prolonged survival. 225Ac‐labeled OTSA101 achieved a complete response in 60% of mice, and no recurrence was observed. 225Ac‐labeled OTSA101 induced a larger amount of necrosis and apoptosis than 90Y‐labeled OTSA101, although the cell proliferation decrease was comparable. The BED for normal organs and tissues was tolerable; no treatment‐related mortality or obvious toxicity, except for temporary body weight loss, was observed. 225Ac‐labeled OTSA101 provided a high BED for tumors and achieved a 60% complete response in the synovial sarcoma mouse model SYO‐1. RIT with 225Ac‐labeled OTSA101 is a promising therapeutic option for synovial sarcoma.
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Affiliation(s)
- Hitomi Sudo
- Department of Molecular Imaging and Theranostics, National Institutes for Quantum and Radiological Science and Technology (QST), Chiba, Japan
| | - Atsushi B Tsuji
- Department of Molecular Imaging and Theranostics, National Institutes for Quantum and Radiological Science and Technology (QST), Chiba, Japan
| | - Aya Sugyo
- Department of Molecular Imaging and Theranostics, National Institutes for Quantum and Radiological Science and Technology (QST), Chiba, Japan
| | | | - Satoshi Nagayama
- Department of Surgery, Uji Tokushukai Medical Center, Kyoto, Japan
| | - Toyomasa Katagiri
- Division of Genome Medicine, Institute of Advanced Medical Sciences, Tokushima University, Tokushima, Japan
| | - Yusuke Nakamura
- Cancer Precision Medicine Center, Japanese Foundation for Cancer Research, Tokyo, Japan
| | - Tatsuya Higashi
- Department of Molecular Imaging and Theranostics, National Institutes for Quantum and Radiological Science and Technology (QST), Chiba, Japan
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Sabbioni E, Groppi F, Di Gioacchino M, Petrarca C, Manenti S. Metallobiochemistry of ultratrace levels of bismuth in the rat I. Metabolic patterns of 205+206Bi 3+ in the blood. J Trace Elem Med Biol 2021; 68:126760. [PMID: 33895056 DOI: 10.1016/j.jtemb.2021.126760] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Revised: 02/22/2021] [Accepted: 04/12/2021] [Indexed: 11/16/2022]
Abstract
BACKGROUND The number of the applications of bismuth (Bi) is rapidly and remarkably increasing, enhancing the chance to increase the levels to which humans are normally daily exposed. The interest to Bi comes also from the potential of Bi-based nanoparticles (BiNPs) for industrial and biomedical purposes. Like other metal-based NPs used in nanomedicine, BiNPs may release ultratrace amounts of Bi ions when injected. The metabolic fate and toxicity of these ions still needs to be evaluated. At present, knowledge of Bi metabolism in laboratory animals refers almost solely to studies under unnatural "extreme" exposures, i.e. pharmacologically relevant high-doses (up to thousand mg kg-1) in relation to its medical use, or infinitesimal-doses (pg kg-1 as non-carrier-added Bi radioisotopes) for radiobiology protection, diagnostic and radiotherapeutic purposes. No specific study exists on the "metabolic patterns" in animal models exposed to levels of Bi, i.e. at "environmental dose exposure" that reflect the human daily exposure (μg kg-1). METHODOLOGY Rats were intraperitoneally injected with 0.8 μg Bi kg-1 bw as 205+206Bi(NO)3 alone or in combination with 59Fe for radiolabelling of iron proteins. The use of 205+206Bi radiotracers allowed the detection and measurement down to pg fg-1 of the element in the blood biochemical compartments and protein fractions as isolated by differential centrifugation, size exclusion- and ion exchange chromatography, electrophoresis, solvent extraction, precipitation and dialysis. RESULTS 24 h after the administration, the blood concentration of Bi was 0.18 ng mL-1, with a repartition plasma/red blod cells (RBC) in a ratio of 2:1. Elution profiles of plasma from gel filtration on Sephadex G-150 showed four pools of Bi-binder proteins with different molecular sizes (> 300 kDa, 160 kDa, 70 kDa and < 6.5 kDa). In the 70 kDa fraction transferrin and albumin were identified as biomolecule carriers for Bi. In red blood cells, Bi was distributed between cytosol and membranes (ghosts) in a ratio of about 5:1. In the cytosol, low molecular components (LMWC) and the hemoglobin associated the Bi in a ratio of about 1.8:1. In the hemoglobin molecule, Bi was bound to the beta polypeptide chain of the globin. In the ghosts, Bi was detected at more than one site of the protein fraction, with no binding with lipids. Dialysis experiments and the consistently high recovery (80-90 %) of 206Bi from chromatography of 206Bi-containing biocomponents suggest that Bi was firmly complexed at physiological pH with a low degree of breaking during the applications of experimental protocols for the isolation of the 206Bi-biocomplexes. These latter were sensitive to acid buffer pH 5, and to the presence of complexing agents in the dialysis fluid. CONCLUSIONS On the basis of an environmental biochemical toxicology approach, we have undertaken a study on the metabolic patterns of Bi3+ ions in rats at tissue, subcellular and molecular level with the identification of cellular Bi-binding components. As a first part of the study the present work reports the results concerned with the metabolic fate of ultratrace levels of 205+206Bi(NO)3 in the blood.
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Affiliation(s)
- Enrico Sabbioni
- Center for Advanced Studies and Technology (C.A.S.T.), "G. d'Annunzio" University of Chieti-Pescara, Via Luigi Polacchi 11, Chieti, I-66100, Italy; LASA, Department of Physics, Università Degli Studi di Milano and INFN-Milano, Via F.lli Cervi 201, Segrate, MI, I-20090, Italy
| | - Flavia Groppi
- Department of Physics, Università Degli Studi di Milano, Via Celoria 16, Milano, I-20133, Italy; LASA, Department of Physics, Università Degli Studi di Milano and INFN-Milano, Via F.lli Cervi 201, Segrate, MI, I-20090, Italy
| | - Mario Di Gioacchino
- Center for Advanced Studies and Technology (C.A.S.T.), "G. d'Annunzio" University of Chieti-Pescara, Via Luigi Polacchi 11, Chieti, I-66100, Italy; Institute of Clinical Immunotherapy and Advanced Biological Treatments, Piazza Pierangeli 1, Pescara, Rectorate of Leonardo da Vinci Telematic University, Largo San Rocco 11 Torrevecchia Teatina, CH, Italy
| | - Claudia Petrarca
- Center for Advanced Studies and Technology (C.A.S.T.), "G. d'Annunzio" University of Chieti-Pescara, Via Luigi Polacchi 11, Chieti, I-66100, Italy; Department of Medicine and Aging Sciences, "G. d'Annunzio" University of Chieti-Pescara, via Luigi Polacchi 11, Chieti, I-66100, Italy
| | - Simone Manenti
- Department of Physics, Università Degli Studi di Milano, Via Celoria 16, Milano, I-20133, Italy; LASA, Department of Physics, Università Degli Studi di Milano and INFN-Milano, Via F.lli Cervi 201, Segrate, MI, I-20090, Italy.
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King AP, Lin FI, Escorcia FE. Why bother with alpha particles? Eur J Nucl Med Mol Imaging 2021; 49:7-17. [PMID: 34175980 DOI: 10.1007/s00259-021-05431-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2021] [Accepted: 05/24/2021] [Indexed: 12/23/2022]
Abstract
The approval of 223RaCl2 for cancer therapy in 2013 has heralded a resurgence of interest in the development of α-particle emitting radiopharmaceuticals. In the last decade, over a dozen α-emitting radiopharmaceuticals have entered clinical trials, spawned by strong preclinical studies. In this article, we explore the potential role of α-particle therapy in cancer treatment. We begin by providing a background for the basic principles of therapy with α-emitters, and we explore recent breakthroughs in therapy with α-emitting radionuclides, including conjugates with small molecules and antibodies. Finally, we discuss some outstanding challenges to the clinical adoption of α-therapies and potential strategies to address them.
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Affiliation(s)
- A Paden King
- Molecular Imaging Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20817, USA
- Radiation Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20817, USA
| | - Frank I Lin
- Molecular Imaging Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20817, USA
| | - Freddy E Escorcia
- Molecular Imaging Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20817, USA.
- Radiation Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20817, USA.
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Moslim MA, Jeyarajah DR. Narrative review of the role of yttrium-90 selective internal radiation therapy in the surgical management of colorectal liver metastases. J Gastrointest Oncol 2021; 12:2438-2446. [PMID: 34790404 DOI: 10.21037/jgo-21-96] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Accepted: 06/08/2021] [Indexed: 11/06/2022] Open
Abstract
The management of colorectal liver metastasis (CRLM) is complicated and benefits from a multidisciplinary team approach. Liver-directed therapy has been emerging as a modality for better progression-free control. In its early years, selective internal radiation therapy (SIRT) with yttrium-90 (Y-90) was confined as an end-of-line therapy. However, literature has supported other roles including: a first-line treatment for CRLM alone or in combination with systemic chemotherapy; an adjunct to second or third-line chemotherapy; and a salvage treatment for chemo-refractory disease. Although future liver remnant (FLR) hypertrophy may take 3-12 months, the SIRT effect on loco-regional disease control has rendered it to be a useful tool in some pathologies with certain strategic goals. This paper reviews the use of SIRT with Y-90 in a surgical treatment pathway. This includes: (I) an element of multidisciplinary treatment of low-volume CRLMs, (II) convert an R1 to R0 resection by sterilizing the margins of tumor near critical structures, and (III) radiation lobectomy to induce contralateral hypertrophy in order to aid in a safer resection. There are many opportunities to validate the role of SIRT as a first-line therapy along with surgical resection including an umbrella clinical trial design.
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Hanaoka H, Ohshima Y, Suzuki H, Sasaki I, Watabe T, Ooe K, Watanabe S, Ishioka NS. Enhancing the Therapeutic Effect of 2- 211At-astato-α-methyl-L-phenylalanine with Probenecid Loading. Cancers (Basel) 2021; 13:cancers13215514. [PMID: 34771676 PMCID: PMC8583516 DOI: 10.3390/cancers13215514] [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: 10/22/2021] [Accepted: 10/28/2021] [Indexed: 11/24/2022] Open
Abstract
Simple Summary To enhance the therapeutic effect of 2-211At-astato-α-methyl-L-phenylalanine (2-211At-AAMP), a radiopharmaceutical for targeted alpha therapy, we evaluated the effect of probenecid loading on its biodistribution and therapeutic effect in mice. Probenecid preloading significantly delayed the clearance of 2-211At-AAMP from the blood, increasing its accumulation in tumors. Consequently, the therapeutic effect of 2-211At-AAMP markedly improved. These results indicate that 2-211At-AAMP with probenecid loading is useful for the treatment of various types of cancers. Abstract L-type amino acid transporter 1 (LAT1) might be a useful target for tumor therapy since it is highly expressed in various types of cancers. We previously developed an astatine-211 (211At)-labeled amino acid derivative, 2-211At-astato-α-methyl-L-phenylalanine (2-211At-AAMP), and demonstrated its therapeutic potential for LAT1-positive cancers. However, the therapeutic effect of 2-211At-AAMP was insufficient, probably due to its low tumor retention. The preloading of probenecid, an organic anion transporter inhibitor, can delay the clearance of some amino acid tracers from the blood and consequently increase their accumulation in tumors. In this study, we evaluated the effect of probenecid preloading on the biodistribution and therapeutic effect of 2-211At-AAMP in mice. In biodistribution studies, the blood radioactivity of 2-211At-AAMP significantly increased with probenecid preloading. Consequently, the accumulation of 2-211At-AAMP in tumors was significantly higher with probenecid than without probenecid loading. In a therapeutic study, tumor growth was suppressed by 2-211At-AAMP with probenecid, and the tumor volume was significantly lower in the treatment group than in the untreated control group from day 2 to day 30 (end of the follow-up period) after treatment. These results indicate that probenecid loading could improve the therapeutic effect of 2-211At-AAMP by increasing its accumulation in tumors.
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Affiliation(s)
- Hirofumi Hanaoka
- Faculty of Medicine, Kansai Medical University, 2-5-1 Shin-machi, Hirakata 573-1010, Osaka, Japan
- Department of Radiotheranostics, Gunma University Graduate School of Medicine, 3-39-22 Showa-machi, Maebashi 371-8511, Gunma, Japan
- Correspondence: ; Tel.: +81-72-804-2452
| | - Yasuhiro Ohshima
- Department of Radiation-Applied Biology Research, Quantum Beam Science Research Directorate, National Institute for Quantum Science and Technology, 1233 Watanuki-machi, Takasaki 370-1292, Gunma, Japan; (Y.O.); (I.S.); (S.W.); (N.S.I.)
| | - Hiroyuki Suzuki
- Department of Molecular Imaging and Radiotherapy, Graduate School of Pharmaceutical Science, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8675, Chiba, Japan;
| | - Ichiro Sasaki
- Department of Radiation-Applied Biology Research, Quantum Beam Science Research Directorate, National Institute for Quantum Science and Technology, 1233 Watanuki-machi, Takasaki 370-1292, Gunma, Japan; (Y.O.); (I.S.); (S.W.); (N.S.I.)
| | - Tadashi Watabe
- Department of Nuclear Medicine and Tracer Kinetics, Graduate School of Medicine, Osaka University, 1-1 Yamadaoka, Suita 565-0871, Osaka, Japan; (T.W.); (K.O.)
| | - Kazuhiro Ooe
- Department of Nuclear Medicine and Tracer Kinetics, Graduate School of Medicine, Osaka University, 1-1 Yamadaoka, Suita 565-0871, Osaka, Japan; (T.W.); (K.O.)
| | - Shigeki Watanabe
- Department of Radiation-Applied Biology Research, Quantum Beam Science Research Directorate, National Institute for Quantum Science and Technology, 1233 Watanuki-machi, Takasaki 370-1292, Gunma, Japan; (Y.O.); (I.S.); (S.W.); (N.S.I.)
| | - Noriko S. Ishioka
- Department of Radiation-Applied Biology Research, Quantum Beam Science Research Directorate, National Institute for Quantum Science and Technology, 1233 Watanuki-machi, Takasaki 370-1292, Gunma, Japan; (Y.O.); (I.S.); (S.W.); (N.S.I.)
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Birindelli G, Drobnjakovic M, Morath V, Steiger K, D'Alessandria C, Gourni E, Afshar-Oromieh A, Weber W, Rominger A, Eiber M, Shi K. In silico study on radiobiological efficacy of Ac-225 and Lu-177 for PSMA-guided radiotherapy. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2021; 2021:4497-4500. [PMID: 34892217 DOI: 10.1109/embc46164.2021.9630297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The good efficacy of radioligand therapy (RLT) targeting prostate specific-membrane antigen (PSMA) for the treatment of metastatic castration-resistant prostate cancer (mCRPC) has been recently demonstrated in several clinical studies. However, the treatment effect of 177Lu-PSMA-ligands is still suboptimal for a significant fraction of patients. In contrast to external beam radiotherapy, the radiation dose distribution itself is strongly influenced by the heterogeneous tumour microenvironment. Although microdosimetry is critical for RLT treatment outcome, it is difficult to clinically or experimentally establish the quantitative relation. We propose an in silico approach to quantitatively investigate the microdosimetry and its influence on treatment outcome for PSMA-directed RLT of two different radioisotopes 177Lu and 225 Ac. The ultimate goal is optimize the combined 177 Lu and 225 Ac-PSMA therapy and maximize the anti-tumour effect, while minimizing irradiation of off-target tissues.Clinical relevance- With the proposed hybrid model we show that 177Lu-PSMA-ligands treatment assures a more homogeneously distributed dose and a lower dependency of the treatment outcome on the domain vascularisation. On the other hand, the 225Ac-PSMA-ligands treatment shows a much stronger efficacy in killing tumor cells with an equivalent mean dose distribution even in an hypoxic environment.
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