1
|
Singh N, Rana N, Thakral P, Malik D, Schultz MK, Sen IB. Charting the Course of Targeted α Therapy With First-in-Human, Postadministration Image-Guided Dosimetry and Response Assessment of 212 Pb-VMT-α-NET in Metastatic Neuroendocrine Tumors. Clin Nucl Med 2024; 49:546-548. [PMID: 38537249 DOI: 10.1097/rlu.0000000000005190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
ABSTRACT 212 Pb emerges as a compelling in vivo α-particle generator for targeted α therapy due to its favorable half-life ( t1/2 = 10.6 hours) aligning with the biological half-lives of small peptides and its potent α-particle emissions within the decay series. However, one of the challenges with 212 Pb is to perform appropriate image-guided dosimetry. To date, all the data have been extrapolated from its imaging analog, 203 Pb. We present the first-in-human posttherapy image-guided dosimetric estimates of a single cycle of 212 Pb VMT-α-peptide, administered in a 41-year-old woman with an advanced grade 2 NET. The patient also demonstrated partial response on treatment.
Collapse
Affiliation(s)
- Navneet Singh
- From the Department of Nuclear Medicine, Fortis Memorial Research Institute; and, Gurgaon, Haryana, India
| | - Nishant Rana
- From the Department of Nuclear Medicine, Fortis Memorial Research Institute; and, Gurgaon, Haryana, India
| | - Parul Thakral
- From the Department of Nuclear Medicine, Fortis Memorial Research Institute; and, Gurgaon, Haryana, India
| | - Dharmender Malik
- From the Department of Nuclear Medicine, Fortis Memorial Research Institute; and, Gurgaon, Haryana, India
| | | | - Ishita B Sen
- From the Department of Nuclear Medicine, Fortis Memorial Research Institute; and, Gurgaon, Haryana, India
| |
Collapse
|
2
|
Michler E, Kästner D, Brogsitter C, Pretze M, Hartmann H, Freudenberg R, Schultz MK, Kotzerke J. First-in-human SPECT/CT imaging of [ 212Pb]Pb-VMT-α-NET in a patient with metastatic neuroendocrine tumor. Eur J Nucl Med Mol Imaging 2024; 51:1490-1492. [PMID: 37991526 PMCID: PMC10957691 DOI: 10.1007/s00259-023-06529-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Accepted: 11/14/2023] [Indexed: 11/23/2023]
Affiliation(s)
- Enrico Michler
- Department of Nuclear Medicine, University Hospital Carl Gustav Carus, Technische Universität Dresden, Fetscherstraße 74, 01307, Dresden, Germany
| | - David Kästner
- Department of Nuclear Medicine, University Hospital Carl Gustav Carus, Technische Universität Dresden, Fetscherstraße 74, 01307, Dresden, Germany.
| | - Claudia Brogsitter
- Department of Nuclear Medicine, University Hospital Carl Gustav Carus, Technische Universität Dresden, Fetscherstraße 74, 01307, Dresden, Germany
| | - Marc Pretze
- Department of Nuclear Medicine, University Hospital Carl Gustav Carus, Technische Universität Dresden, Fetscherstraße 74, 01307, Dresden, Germany
| | - Holger Hartmann
- Department of Nuclear Medicine, University Hospital Carl Gustav Carus, Technische Universität Dresden, Fetscherstraße 74, 01307, Dresden, Germany
| | - Robert Freudenberg
- Department of Nuclear Medicine, University Hospital Carl Gustav Carus, Technische Universität Dresden, Fetscherstraße 74, 01307, Dresden, Germany
| | | | - Jörg Kotzerke
- Department of Nuclear Medicine, University Hospital Carl Gustav Carus, Technische Universität Dresden, Fetscherstraße 74, 01307, Dresden, Germany
- Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| |
Collapse
|
3
|
Li M, Robles-Planells C, Liu D, Graves SA, Vasquez-Martinez G, Mayoral-Andrade G, Lee D, Rastogi P, Marks BM, Sagastume EA, Weiss RM, Linn-Peirano SC, Johnson FL, Schultz MK, Zepeda-Orozco D. Pre-clinical evaluation of biomarkers for the early detection of nephrotoxicity following alpha-particle radioligand therapy. Eur J Nucl Med Mol Imaging 2024; 51:1395-1408. [PMID: 38095674 PMCID: PMC10957612 DOI: 10.1007/s00259-023-06559-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2023] [Accepted: 12/01/2023] [Indexed: 12/26/2023]
Abstract
PURPOSE Cancer treatment with alpha-emitter-based radioligand therapies (α-RLTs) demonstrates promising tumor responses. Radiolabeled peptides are filtered through glomeruli, followed by potential reabsorption of a fraction by proximal tubules, which may cause acute kidney injury (AKI) and chronic kidney disease (CKD). Because tubular cells are considered the primary site of radiopeptides' renal reabsorption and potential injury, the current use of kidney biomarkers of glomerular functional loss limits the evaluation of possible nephrotoxicity and its early detection. This study aimed to investigate whether urinary secretion of tubular injury biomarkers could be used as an additional non-invasive sensitive diagnostic tool to identify unrecognizable tubular damage and risk of long-term α-RLT nephrotoxicity. METHODS A bifunctional cyclic peptide, melanocortin 1 ligand (MC1L), labeled with [203Pb]Pb-MC1L, was used for [212Pb]Pb-MC1L biodistribution and absorbed dose measurements in CD-1 Elite mice. Mice were treated with [212Pb]Pb-MC1L in a dose-escalation study up to levels of radioactivity intended to induce kidney injury. The approach enabled prospective kidney functional and injury biomarker evaluation and late kidney histological analysis to validate these biomarkers. RESULTS Biodistribution analysis identified [212Pb]Pb-MC1L reabsorption in kidneys with a dose deposition of 2.8, 8.9, and 20 Gy for 0.9, 3.0, and 6.7 MBq injected [212Pb]Pb-MC1L doses, respectively. As expected, mice receiving 6.7 MBq had significant weight loss and CKD evidence based on serum creatinine, cystatin C, and kidney histological alterations 28 weeks after treatment. A dose-dependent urinary neutrophil gelatinase-associated lipocalin (NGAL, tubular injury biomarker) urinary excretion the day after [212Pb]Pb-MC1L treatment highly correlated with the severity of late tubulointerstitial injury and histological findings. CONCLUSION Urine NGAL secretion could be a potential early diagnostic tool to identify unrecognized tubular damage and predict long-term α-RLT-related nephrotoxicity.
Collapse
Affiliation(s)
- Mengshi Li
- Viewpoint Molecular Targeting, Inc. Dba Perspective Therapeutics, Coralville, IA, USA
| | - Claudia Robles-Planells
- Kidney and Urinary Tract Center, Abigail Wexner Research Institute at Nationwide Children's, Columbus, OH, USA
| | - Dijie Liu
- Viewpoint Molecular Targeting, Inc. Dba Perspective Therapeutics, Coralville, IA, USA
| | - Stephen A Graves
- Department of Radiology, The University of Iowa, Iowa City, IA, USA
| | - Gabriela Vasquez-Martinez
- Kidney and Urinary Tract Center, Abigail Wexner Research Institute at Nationwide Children's, Columbus, OH, USA
| | - Gabriel Mayoral-Andrade
- Kidney and Urinary Tract Center, Abigail Wexner Research Institute at Nationwide Children's, Columbus, OH, USA
| | - Dongyoul Lee
- Department of Physics and Chemistry, Korea Military Academy, Seoul, Republic of Korea
| | - Prerna Rastogi
- Department of Pathology, The University of Iowa, Iowa City, IA, USA
| | - Brenna M Marks
- Viewpoint Molecular Targeting, Inc. Dba Perspective Therapeutics, Coralville, IA, USA
| | - Edwin A Sagastume
- Viewpoint Molecular Targeting, Inc. Dba Perspective Therapeutics, Coralville, IA, USA
| | - Robert M Weiss
- Department of Internal Medicine, The University of Iowa, Iowa City, IA, USA
| | - Sarah C Linn-Peirano
- Kidney and Urinary Tract Center, Abigail Wexner Research Institute at Nationwide Children's, Columbus, OH, USA
- Department of Veterinary Biosciences, The Ohio State University College of Veterinary Medicine Columbus, Columbus, OH, USA
| | - Frances L Johnson
- Viewpoint Molecular Targeting, Inc. Dba Perspective Therapeutics, Coralville, IA, USA
| | - Michael K Schultz
- Viewpoint Molecular Targeting, Inc. Dba Perspective Therapeutics, Coralville, IA, USA.
- Department of Radiology, The University of Iowa, Iowa City, IA, USA.
- Department of Radiation Oncology, Free Radical, and Radiation Biology Program, The University of Iowa, Iowa City, IA, USA.
| | - Diana Zepeda-Orozco
- Kidney and Urinary Tract Center, Abigail Wexner Research Institute at Nationwide Children's, Columbus, OH, USA.
- Department of Pediatrics, The Ohio State University College of Medicine, Columbus, OH, USA.
- Division of Nephrology and Hypertension, Nationwide Children's Hospital, Columbus, OH, USA.
| |
Collapse
|
4
|
Gape PMD, Schultz MK, Stasiuk GJ, Terry SYA. Towards Effective Targeted Alpha Therapy for Neuroendocrine Tumours: A Review. Pharmaceuticals (Basel) 2024; 17:334. [PMID: 38543120 PMCID: PMC10974115 DOI: 10.3390/ph17030334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2024] [Revised: 02/22/2024] [Accepted: 02/26/2024] [Indexed: 04/01/2024] Open
Abstract
This review article explores the evolving landscape of Molecular Radiotherapy (MRT), emphasizing Peptide Receptor Radionuclide Therapy (PRRT) for neuroendocrine tumours (NETs). The primary focus is on the transition from β-emitting radiopharmaceuticals to α-emitting agents in PRRT, offering a critical analysis of the radiobiological basis, clinical applications, and ongoing developments in Targeted Alpha Therapy (TAT). Through an extensive literature review, the article delves into the mechanisms and effectiveness of PRRT in targeting somatostatin subtype 2 receptors, highlighting both its successes and limitations. The discussion extends to the emerging paradigm of TAT, underlining its higher potency and specificity with α-particle emissions, which promise enhanced therapeutic efficacy and reduced toxicity. The review critically evaluates preclinical and clinical data, emphasizing the need for standardised dosimetry and a deeper understanding of the dose-response relationship in TAT. The review concludes by underscoring the significant potential of TAT in treating SSTR2-overexpressing cancers, especially in patients refractory to β-PRRT, while also acknowledging the current challenges and the necessity for further research to optimize treatment protocols.
Collapse
Affiliation(s)
- Paul M. D. Gape
- School of Biomedical Engineering & Imaging Sciences, King’s College London, London SE1 7EP, UK; (G.J.S.); (S.Y.A.T.)
| | - Michael K. Schultz
- Departments of Radiology, Radiation Oncology, Free Radical and Radiation Biology Program, University of Iowa, Iowa City, IA 52242, USA;
- Perspective Therapeutics, Coralville, IA 52241, USA
| | - Graeme J. Stasiuk
- School of Biomedical Engineering & Imaging Sciences, King’s College London, London SE1 7EP, UK; (G.J.S.); (S.Y.A.T.)
| | - Samantha Y. A. Terry
- School of Biomedical Engineering & Imaging Sciences, King’s College London, London SE1 7EP, UK; (G.J.S.); (S.Y.A.T.)
| |
Collapse
|
5
|
Lee D, Li M, Liu D, Baumhover NJ, Sagastume EA, Marks BM, Rastogi P, Pigge FC, Menda Y, Johnson FL, Schultz MK. Structural modifications toward improved lead-203/lead-212 peptide-based image-guided alpha-particle radiopharmaceutical therapies for neuroendocrine tumors. Eur J Nucl Med Mol Imaging 2024; 51:1147-1162. [PMID: 37955792 PMCID: PMC10881741 DOI: 10.1007/s00259-023-06494-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Accepted: 10/26/2023] [Indexed: 11/14/2023]
Abstract
PURPOSE The lead-203 (203Pb)/lead-212 (212Pb) elementally identical radionuclide pair has gained significant interest in the field of image-guided targeted alpha-particle therapy for cancer. Emerging evidence suggests that 212Pb-labeled peptide-based radiopharmaceuticals targeting somatostatin receptor subtype 2 (SSTR2) may provide improved effectiveness compared to beta-particle-based therapies for neuroendocrine tumors (NETs). This study aims to improve the performance of SSTR2-targeted radionuclide imaging and therapy through structural modifications to Tyr3-octreotide (TOC)-based radiopharmaceuticals. METHODS New SSTR2-targeted peptides were designed and synthesized with the goal of optimizing the incorporation of Pb isotopes through the use of a modified cyclization technique; the introduction of a Pb-specific chelator (PSC); and the insertion of polyethylene glycol (PEG) linkers. The binding affinity of the peptides and the cellular uptake of 203Pb-labeled peptides were evaluated using pancreatic AR42J (SSTR2+) tumor cells and the biodistribution and imaging of the 203Pb-labeled peptides were assessed in an AR42J tumor xenograft mouse model. A lead peptide was identified (i.e., PSC-PEG2-TOC), which was then further evaluated for efficacy in 212Pb therapy studies. RESULTS The lead radiopeptide drug conjugate (RPDC) - [203Pb]Pb-PSC-PEG2-TOC - significantly improved the tumor-targeting properties, including receptor binding and tumor accumulation and retention as compared to [203Pb]Pb-DOTA0-Tyr3-octreotide (DOTATOC). Additionally, the modified RPDC exhibited faster renal clearance than the DOTATOC counterpart. These advantageous characteristics of [212Pb]Pb-PSC-PEG2-TOC resulted in a dose-dependent therapeutic effect with minimal signs of toxicity in the AR42J xenograft model. Fractionated administrations of 3.7 MBq [212Pb]Pb-PSC-PEG2-TOC over three doses further improved anti-tumor effectiveness, resulting in 80% survival (70% complete response) over 120 days in the mouse model. CONCLUSION Structural modifications to chelator and linker compositions improved tumor targeting and pharmacokinetics (PK) of 203/212Pb peptide-based radiopharmaceuticals for NET theranostics. These findings suggest that PSC-PEG2-TOC is a promising candidate for Pb-based targeted radionuclide therapy for NETs and other types of cancers that express SSTR2.
Collapse
Affiliation(s)
- Dongyoul Lee
- Department of Physics and Chemistry, Korea Military Academy, Seoul, Republic of Korea
| | - Mengshi Li
- Perspective Therapeutics, Inc., Coralville, IA, USA
| | - Dijie Liu
- Perspective Therapeutics, Inc., Coralville, IA, USA
| | | | | | | | - Prerna Rastogi
- Department of Pathology, The University of Iowa Hospitals and Clinics, Iowa City, IA, USA
| | - F Christopher Pigge
- Department of Chemistry, The University of Iowa, ML B180 FRRBP, 500 Newton Road, Iowa City, IA, 52240, USA
| | - Yusuf Menda
- Department of Radiology, The University of Iowa Hospitals and Clinics, Iowa City, IA, USA
| | | | - Michael K Schultz
- Perspective Therapeutics, Inc., Coralville, IA, USA.
- Department of Chemistry, The University of Iowa, ML B180 FRRBP, 500 Newton Road, Iowa City, IA, 52240, USA.
- Department of Radiology, The University of Iowa Hospitals and Clinics, Iowa City, IA, USA.
- Department of Radiation Oncology, The University of Iowa Hospitals and Clinics, Iowa City, IA, USA.
| |
Collapse
|
6
|
Bauer D, Carter LM, Atmane MI, De Gregorio R, Michel A, Kaminsky S, Monette S, Li M, Schultz MK, Lewis JS. 212Pb-Pretargeted Theranostics for Pancreatic Cancer. J Nucl Med 2024; 65:109-116. [PMID: 37945380 PMCID: PMC10755526 DOI: 10.2967/jnumed.123.266388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Revised: 09/28/2023] [Indexed: 11/12/2023] Open
Abstract
Although pancreatic ductal adenocarcinoma (PDAC) is associated with limited treatment options and poor patient outcomes, targeted α-particle therapy (TAT) represents a promising development in the field. TAT shows potential in treating metastatic cancers, including those that have become resistant to conventional treatments. Among the most auspicious radionuclides stands the in vivo α-generator 212Pb. Combined with the imaging-compatible radionuclide 203Pb, this theranostic match is a promising modality rapidly translating into the clinic. Methods: Using the pretargeting approach between a radiolabeled 1,2,4,5-tetrazine (Tz) tracer and a trans-cyclooctene (TCO) modified antibody, imaging and therapy with radiolead were performed on a PDAC tumor xenograft mouse model. For therapy, 3 cohorts received a single administration of 1.1, 2.2, or 3.7 MBq of the pretargeting agent, [212Pb]Pb-DO3A-PEG7-Tz, whereby administered activity levels were guided by dosimetric analysis. Results: The treated mice were holistically evaluated; minimal-to-mild renal tubular necrosis was observed. At the same time, median survival doubled for the highest-dose cohort (10.7 wk) compared with the control cohort (5.1 wk). Conclusion: This foundational study demonstrated the feasibility and safety of pretargeted TAT with 212Pb in PDAC while considering dose limitations and potential adverse effects.
Collapse
Affiliation(s)
- David Bauer
- Department of Radiology and Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Lukas M Carter
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Mohamed I Atmane
- Laboratory of Comparative Pathology, Memorial Sloan Kettering Cancer Center, Weill Cornell Medicine, and Rockefeller University, New York, New York
| | - Roberto De Gregorio
- Department of Radiology and Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Alexa Michel
- Department of Radiology and Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Spencer Kaminsky
- Department of Radiology and Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Sebastien Monette
- Laboratory of Comparative Pathology, Memorial Sloan Kettering Cancer Center, Weill Cornell Medicine, and Rockefeller University, New York, New York
| | - Mengshi Li
- Perspective Therapeutics, Inc., Coralville, Iowa; and
| | | | - Jason S Lewis
- Department of Radiology and Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, New York;
- Department of Radiology and Pharmacology Program, Weill Cornell Medical College, New York, New York
| |
Collapse
|
7
|
Pretze M, Michler E, Runge R, Wetzig K, Tietze K, Brandt F, Schultz MK, Kotzerke J. Influence of the Molar Activity of 203/212Pb-PSC-PEG 2-TOC on Somatostatin Receptor Type 2-Binding and Cell Uptake. Pharmaceuticals (Basel) 2023; 16:1605. [PMID: 38004470 PMCID: PMC10675797 DOI: 10.3390/ph16111605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Revised: 11/06/2023] [Accepted: 11/10/2023] [Indexed: 11/26/2023] Open
Abstract
(1) Background: In neuroendocrine tumors (NETs), somatostatin receptor subtype 2 is highly expressed, which can be targeted by a radioactive ligand such as [177Lu]Lu-1,4,7,10-tetraazacyclododecane-N,N',N″,N‴,-tetraacetic acid-[Tyr3,Thr8]-octreotide (177Lu-DOTA-TOC) and, more recently, by a lead specific chelator (PSC) containing 203/212Pb-PSC-PEG2-TOC (PSC-TOC). The molar activity (AM) can play a crucial role in tumor uptake, especially in receptor-mediated uptake, such as in NETs. Therefore, an investigation of the influence of different molar activities of 203/212Pb-PSC-TOC on cell uptake was investigated. (2) Methods: Optimized radiolabeling of 203/212Pb-PSC-TOC was performed with 50 µg of precursor in a NaAc/AcOH buffer at pH 5.3-5.5 within 15-45 min at 95° C. Cell uptake was studied in AR42 J, HEK293 sst2, and ZR75-1 cells. (3) Results: 203/212Pb-PSC-TOC was radiolabeled with high radiochemical purity >95% and high radiochemical yield >95%, with AM ranging from 0.2 to 61.6 MBq/nmol. The cell uptake of 203Pb-PSC-TOC (AM = 38 MBq/nmol) was highest in AR42 J (17.9%), moderate in HEK293 sstr (9.1%) and lowest in ZR75-1 (0.6%). Cell uptake increased with the level of AM. (4) Conclusions: A moderate AM of 15-40 MBq/nmol showed the highest cell uptake. No uptake limitation was found in the first 24-48 h. Further escalation experiments with even higher AM should be performed in the future. It was shown that AM plays an important role because of its direct dependence on the cellular uptake levels, possibly due to less receptor saturation with non-radioactive ligands at higher AM.
Collapse
Affiliation(s)
- Marc Pretze
- Department of Nuclear Medicine, University Hospital Carl Gustav Carus, Technical University Dresden, Fetscherstr. 74, 01307 Dresden, Germany; (E.M.); (R.R.); (K.W.); (K.T.); (F.B.); (J.K.)
| | - Enrico Michler
- Department of Nuclear Medicine, University Hospital Carl Gustav Carus, Technical University Dresden, Fetscherstr. 74, 01307 Dresden, Germany; (E.M.); (R.R.); (K.W.); (K.T.); (F.B.); (J.K.)
| | - Roswitha Runge
- Department of Nuclear Medicine, University Hospital Carl Gustav Carus, Technical University Dresden, Fetscherstr. 74, 01307 Dresden, Germany; (E.M.); (R.R.); (K.W.); (K.T.); (F.B.); (J.K.)
| | - Kerstin Wetzig
- Department of Nuclear Medicine, University Hospital Carl Gustav Carus, Technical University Dresden, Fetscherstr. 74, 01307 Dresden, Germany; (E.M.); (R.R.); (K.W.); (K.T.); (F.B.); (J.K.)
| | - Katja Tietze
- Department of Nuclear Medicine, University Hospital Carl Gustav Carus, Technical University Dresden, Fetscherstr. 74, 01307 Dresden, Germany; (E.M.); (R.R.); (K.W.); (K.T.); (F.B.); (J.K.)
| | - Florian Brandt
- Department of Nuclear Medicine, University Hospital Carl Gustav Carus, Technical University Dresden, Fetscherstr. 74, 01307 Dresden, Germany; (E.M.); (R.R.); (K.W.); (K.T.); (F.B.); (J.K.)
| | - Michael K. Schultz
- Department of Radiology, University of Iowa, Iowa City, IA 52240, USA;
- Viewpoint Molecular Targeting, Inc. (DBA Perspective Therapeutics), Coralville, IA 52241, USA
- Department of Chemistry, University of Iowa, Iowa City, IA 52241, USA
- Department of Radiation Oncology, University of Iowa, Iowa City, IA 52242, USA
| | - Jörg Kotzerke
- Department of Nuclear Medicine, University Hospital Carl Gustav Carus, Technical University Dresden, Fetscherstr. 74, 01307 Dresden, Germany; (E.M.); (R.R.); (K.W.); (K.T.); (F.B.); (J.K.)
| |
Collapse
|
8
|
Saini S, Bartels JL, Appiah JPK, Rider JH, Baumhover N, Schultz MK, Lapi SE. Optimized Methods for the Production of High-Purity 203Pb Using Electroplated Thallium Targets. J Nucl Med 2023; 64:1791-1797. [PMID: 37652545 DOI: 10.2967/jnumed.123.265976] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Revised: 07/17/2023] [Indexed: 09/02/2023] Open
Abstract
203Pb is a surrogate imaging match for 212Pb. This elementally matched pair is emerging as a suitable pair for imaging and targeted radionuclide therapy in cancer care. Because of the half-life (51.9 h) and low-energy γ-rays emitted, 203Pb is suitable for the development of diagnostic radiopharmaceuticals. The aim of this work was to optimize the production and separation of high-specific-activity 203Pb using electroplated thallium targets. We further investigated the radiochemistry optimization using a suitable chelator, tetraazacyclododecane-1,4,7-triacetic acid (DO3A), and targeting vector, VMT-α-NET (lead-specific chelator conjugated to tyr3-octreotide via a polyethylene glycol linker). Methods: Targets were prepared by electroplating of natural or enriched (205Tl) thallium metal. Scanning electron microscopy was performed to determine the structure and elemental composition of electroplated targets. Targets were irradiated with 24-MeV protons with varying current and beam time to investigate target durability. 203Pb was purified from the thallium target material using an extraction resin (lead resin) column followed by a second column using a weak cation-exchange resin to elute the lead isotope as [203Pb]PbCl2 Inductively coupled plasma mass spectrometry studies were used to further characterize the separation for trace metal contaminants. Radiolabeling efficiency was also investigated for DO3A chelator and VMT-α-NET (a peptide-based targeting conjugate). Results: Electroplated targets were prepared at a high plating density of 76-114 mg/cm2 using a plating time of 5 h. A reproducible separation method was established with a final elution in HCl (400 μL, 1 M) suitable for radiolabeling. Greater than 90% recovery yields were achieved, with an average specific activity of 37.7 ± 5.4 GBq/μmol (1.1 ± 0.1 Ci/μmol). Conclusion: An efficient electroplating method was developed to prepare thallium targets suitable for cyclotron irradiation. A simple and fast separation method was developed for routine 203Pb production with high recovery yields and purity.
Collapse
Affiliation(s)
- Shefali Saini
- Department of Radiology, University of Alabama at Birmingham, Birmingham, Alabama; and
| | - Jennifer L Bartels
- Department of Radiology, University of Alabama at Birmingham, Birmingham, Alabama; and
| | - Jean-Pierre K Appiah
- Department of Radiology, University of Alabama at Birmingham, Birmingham, Alabama; and
| | - Jason H Rider
- Department of Radiology, University of Alabama at Birmingham, Birmingham, Alabama; and
| | | | | | - Suzanne E Lapi
- Department of Radiology, University of Alabama at Birmingham, Birmingham, Alabama; and
| |
Collapse
|
9
|
Li M, Robles-Planells C, Liu D, Graves SA, Vasquez-Martinez G, Mayoral-Andrade G, Lee D, Rastogi P, Marks BM, Sagastume EA, Weiss RM, Linn-Peirano SC, Johnson FL, Schultz MK, Zepeda-Orozco D. Pre-clinical Evaluation of Biomarkers for Early Detection of Nephrotoxicity Following Alpha-particle Radioligand Therapy. bioRxiv 2023:2023.09.27.559789. [PMID: 37808634 PMCID: PMC10557737 DOI: 10.1101/2023.09.27.559789] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/10/2023]
Abstract
Purpose Cancer treatment with alpha-emitter-based radioligand therapies (α-RLTs) demonstrates promising tumor responses. Radiolabeled peptides are filtered through glomeruli, followed by potential reabsorption of a fraction by proximal tubules, which may cause acute kidney injury (AKI) and chronic kidney disease (CKD). Because tubular cells are considered the primary site of radiopeptides' renal reabsorption and potential injury, the current use of kidney biomarkers of glomerular functional loss limits the evaluation of possible nephrotoxicity and its early detection. This study aimed to investigate whether urinary secretion of tubular injury biomarkers could be used as additional non-invasive sensitive diagnostic tool to identify unrecognizable tubular damage and risk of long-term α-RLTs nephrotoxicity. Methods A bifunctional cyclic peptide, melanocortin ligand-1(MC1L), labeled with [ 203 Pb]Pb-MC1L, was used for [ 212 Pb]Pb-MC1L biodistribution and absorbed dose measurements in CD-1 Elite mice. Mice were treated with [ 212 Pb]Pb-MC1L in a dose escalation study up to levels of radioactivity intended to induce kidney injury. The approach enabled prospective kidney functional and injury biomarker evaluation and late kidney histological analysis to validate these biomarkers. Results Biodistribution analysis identified [ 212 Pb]Pb-MC1L reabsorption in kidneys with a dose deposition of 2.8, 8.9, and 20 Gy for 0.9, 3.0, and 6.7 MBq injected [ 212 Pb]Pb-MC1L doses, respectively. As expected, mice receiving 6.7 MBq had significant weight loss and CKD evidence based on serum creatinine, cystatin C, and kidney histological alterations 28 weeks after treatment. A dose-dependent urinary Neutrophil gelatinase-associated lipocalin (NGAL, tubular injury biomarker) urinary excretion the day after [ 212 Pb]Pb-MC1L treatment highly correlated with the severity of late tubulointerstitial injury and histological findings. Conclusion urine NGAL secretion could be a potential early diagnostic tool to identify unrecognized tubular damage and predict long-term α-RLT-related nephrotoxicity.
Collapse
|
10
|
Li M, Baumhover NJ, Liu D, Cagle BS, Boschetti F, Paulin G, Lee D, Dai Z, Obot ER, Marks BM, Okeil I, Sagastume EA, Gabr M, Pigge FC, Johnson FL, Schultz MK. Preclinical Evaluation of a Lead Specific Chelator (PSC) Conjugated to Radiopeptides for 203Pb and 212Pb-Based Theranostics. Pharmaceutics 2023; 15:414. [PMID: 36839736 PMCID: PMC9966725 DOI: 10.3390/pharmaceutics15020414] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 12/30/2022] [Accepted: 01/14/2023] [Indexed: 01/28/2023] Open
Abstract
203Pb and 212Pb have emerged as promising theranostic isotopes for image-guided α-particle radionuclide therapy for cancers. Here, we report a cyclen-based Pb specific chelator (PSC) that is conjugated to tyr3-octreotide via a PEG2 linker (PSC-PEG-T) targeting somatostatin receptor subtype 2 (SSTR2). PSC-PEG-T could be labeled efficiently to purified 212Pb at 25 °C and also to 212Bi at 80 °C. Efficient radiolabeling of mixed 212Pb and 212Bi in PSC-PEG-T was also observed at 80 °C. Post radiolabeling, stable Pb(II) and Bi(III) radiometal complexes in saline were observed after incubating [203Pb]Pb-PSC-PEG-T for 72 h and [212Bi]Bi-PSC-PEG-T for 5 h. Stable [212Pb]Pb-PSC-PEG-T and progeny [212Bi]Bi-PSC-PEG-T were identified after storage in saline for 24 h. In serum, stable radiometal/radiopeptide were observed after incubating [203Pb]Pb-PSC-PEG-T for 55 h and [212Pb]Pb-PSC-PEG-T for 24 h. In vivo biodistribution of [212Pb]Pb-PSC-PEG-T in tumor-free CD-1 Elite mice and athymic mice bearing AR42J xenografts revealed rapid tumor accumulation, excellent tumor retention and fast renal clearance of both 212Pb and 212Bi, with no in vivo redistribution of progeny 212Bi. Single-photon emission computed tomography (SPECT) imaging of [203Pb]Pb-PSC-PEG-T and [212Pb]Pb-PSC-PEG-T in mice also demonstrated comparable accumulation in AR42J xenografts and renal clearance, confirming the theranostic potential of the elementally identical 203Pb/212Pb radionuclide pair.
Collapse
Affiliation(s)
- Mengshi Li
- Viewpoint Molecular Targeting, Inc., 2500 Crosspark Road, Coralville, IA 52241, USA
| | | | - Dijie Liu
- Viewpoint Molecular Targeting, Inc., 2500 Crosspark Road, Coralville, IA 52241, USA
| | - Brianna S. Cagle
- Viewpoint Molecular Targeting, Inc., 2500 Crosspark Road, Coralville, IA 52241, USA
| | | | | | - Dongyoul Lee
- Department of Physics and Chemistry, Korea Military Academy, Seoul 01805, Republic of Korea
| | - Zhiming Dai
- Department of Chemistry, The University of Iowa, Iowa City, IA 52240, USA
| | - Ephraim R. Obot
- Viewpoint Molecular Targeting, Inc., 2500 Crosspark Road, Coralville, IA 52241, USA
| | - Brenna M. Marks
- Viewpoint Molecular Targeting, Inc., 2500 Crosspark Road, Coralville, IA 52241, USA
| | - Ibrahim Okeil
- Viewpoint Molecular Targeting, Inc., 2500 Crosspark Road, Coralville, IA 52241, USA
| | - Edwin A. Sagastume
- Viewpoint Molecular Targeting, Inc., 2500 Crosspark Road, Coralville, IA 52241, USA
| | - Moustafa Gabr
- Department of Radiology, Weill Cornell Medicine, New York, NY 10021, USA
| | | | - Frances L. Johnson
- Viewpoint Molecular Targeting, Inc., 2500 Crosspark Road, Coralville, IA 52241, USA
| | - Michael K. Schultz
- Viewpoint Molecular Targeting, Inc., 2500 Crosspark Road, Coralville, IA 52241, USA
- Department of Radiology, The University of Iowa, Iowa City, IA 52246, USA
- Department of Radiation Oncology, The University of Iowa, Iowa City, IA 52246, USA
| |
Collapse
|
11
|
Müller D, Herrmann H, Schultz MK, Solbach C, Ettrich T, Prasad V. 203 Pb-VMT-α-NET Scintigraphy of a Patient With Neuroendocrine Tumor. Clin Nucl Med 2023; 48:54-55. [PMID: 36257061 PMCID: PMC9762701 DOI: 10.1097/rlu.0000000000004464] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Revised: 09/15/2022] [Indexed: 11/26/2022]
Abstract
ABSTRACT In an end-stage midgut neuroendocrine tumor patient with carcinoid heart disease, right ventricular dysfunction, mildly reduced renal function, and refractory to 6 cycles of 177 Lu-HA-DOTATATE therapy, planar, and 22 hours SPECT/CT images were acquired after injection of 224 MBq of 203 Pb-VMT-α-NET to assess the feasibility of performing 212 Pb-VMT-α-NET therapy. A comparison of the 1.5 and 22 hours SPECT/CT images with 68 Ga-HA-DOTATATE PET/CT showed high uptake of 203 Pb-VMT-α-NET in liver metastases matching with the results of the PET/CT investigation.
Collapse
Affiliation(s)
- Dirk Müller
- From the Department of Nuclear Medicine, University of Ulm, Ulm, Germany
| | - Hendrik Herrmann
- From the Department of Nuclear Medicine, University of Ulm, Ulm, Germany
| | | | - Christoph Solbach
- From the Department of Nuclear Medicine, University of Ulm, Ulm, Germany
| | - Thomas Ettrich
- Clinic of Internal Medicine, University of Ulm, Ulm, Germany
| | - Vikas Prasad
- From the Department of Nuclear Medicine, University of Ulm, Ulm, Germany
| |
Collapse
|
12
|
Nelson BJB, Wilson J, Schultz MK, Andersson JD, Wuest F. High-yield cyclotron production of 203Pb using a sealed 205Tl solid target. Nucl Med Biol 2023; 116-117:108314. [PMID: 36708660 DOI: 10.1016/j.nucmedbio.2023.108314] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 12/15/2022] [Accepted: 01/02/2023] [Indexed: 01/15/2023]
Abstract
INTRODUCTION 203Pb (t1/2 = 51.9 h, 279 keV (81 %)) is a diagnostic SPECT imaging radionuclide ideally suited for theranostic applications in combination with 212Pb for targeted alpha particle therapy. Our objectives were to develop a high-yield solid target 203Pb cyclotron production route using isotopically enriched 205Tl target material and the 205Tl(p,3n)203Pb reaction as an alternative to lower energy production via the 203Tl(p,n)203Pb reaction. METHODS 250 mg 205Tl metal (99.9 % isotopic enrichment) was pressed using a hardened stainless steel die. Aluminum target discs were machined with a central depression and annulus groove. The flattened 205Tl pellet was placed into the central depression of the Al disc and a circle of indium wire was laid in the machined annulus surrounding the pellet. An aluminum foil cover was then pressed onto the target disc to create an airtight bond. Targets were irradiated at 23.3 MeV for up to 516 min on a TR-24 cyclotron at currents up to 60 μA to produce 203Pb via the 205Tl(p,3n)203Pb nuclear reaction. Following a cool-down period of >12 h, the target was removed and 205Tl dissolved in 4 M HNO3. A NEPTIS Mosaic-LC synthesis unit performed automated separation using Eichrom Pb resin, and 203Pb was eluted using 8 M HCl or 1 M NH4OAc. 205Tl was diverted to a vial for recovery in an electrolytic cell. 203Pb product radionuclidic purity was assessed by HPGe gamma spectroscopy, while elemental purity was assessed by ICP-OES. Radiolabeling and stability studies were performed with PSC, TCMC, and DOTA chelators, and 203Pb incorporation was verified by radio-TLC analysis. RESULTS Cyclotron irradiations performed at 60 μA proton beam current and 23.3 MeV (205Tl incident energy) had a 203Pb saturated yield of 4658 ± 62 MBq/μA (n = 3). Automated NEPTIS separation took <4 h from the start of target dissolution to product elution, yielding >85 % decay-corrected [203Pb]PbCl2 with a radionuclidic purity of >99.9 %. Purified [203Pb]PbCl2 yields of up to 12 GBq 203Pb were attained (15.8 GBq at EOB). The [203Pb]PbCl2 and [203Pb]Pb(OAc)2 products contained no detectable radionuclidic impurities besides 201Pb (<0.1 %), and <0.4 ppm stable Pb. 205Tl metal was recovered with a 92 % batch yield. Aliquots of 100 μL [203Pb]Pb(OAc)2 were used for radiolabeling PSC-Bn-NCS, TCMC-NCS, and DOTA-NCS chelators at pH 4.5 and 22 °C for 30 min, with maximum respective molar activities of 461 ± 30 GBq/μmol, 195 ± 37 GBq/μmol, and 83 ± 12 GBq/μmol. PSC, TCMC, and DOTA chelators exhibited >99.9 % incorporation after a 120-hour incubation in human serum at 37 °C. CONCLUSIONS Nuclear medicine centers with access to higher energy cyclotrons can produce large 203Pb activities sufficient for clinical applications, with a convenient separation technique producing highly pure [203Pb]PbCl2 or [203Pb]Pb(OAc)2 for direct radiolabeling. This represents an attractive route to produce 203Pb for diagnostic SPECT imaging alongside 212Pb targeted alpha particle therapy. ADVANCES IN KNOWLEDGE AND IMPLICATIONS FOR PATIENT CARE Our high-yield 203Pb production technique significantly enhances 203Pb production capabilities to meet the growing preclinical and clinical demand for 203Pb radiopharmaceuticals alongside 212Pb target alpha particle therapy.
Collapse
Affiliation(s)
- Bryce J B Nelson
- Department of Oncology, Cross Cancer Institute, University of Alberta, Edmonton, Alberta T6G 1Z2, Canada
| | - John Wilson
- Department of Oncology, Cross Cancer Institute, University of Alberta, Edmonton, Alberta T6G 1Z2, Canada
| | - Michael K Schultz
- Viewpoint Molecular Targeting, Inc., Coralville, IA 52241, USA; Department of Radiology, The University of Iowa, Iowa City, IA 52240, USA
| | - Jan D Andersson
- Department of Oncology, Cross Cancer Institute, University of Alberta, Edmonton, Alberta T6G 1Z2, Canada; Edmonton Radiopharmaceutical Center, Alberta Health Services, Edmonton, Alberta T6G 1Z2, Canada
| | - Frank Wuest
- Department of Oncology, Cross Cancer Institute, University of Alberta, Edmonton, Alberta T6G 1Z2, Canada; Cancer Research Institute of Northern Alberta, University of Alberta, Edmonton, Alberta T6G 2E1, Canada.
| |
Collapse
|
13
|
Orcutt KD, Henry KE, Habjan C, Palmer K, Heimann J, Cupido JM, Gottumukkala V, Cissell DD, Lyon MC, Hussein AI, Liu D, Li M, Johnson FL, Schultz MK. Dosimetry of [ 212Pb]VMT01, a MC1R-Targeted Alpha Therapeutic Compound, and Effect of Free 208Tl on Tissue Absorbed Doses. Molecules 2022; 27:molecules27185831. [PMID: 36144563 PMCID: PMC9504749 DOI: 10.3390/molecules27185831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Revised: 08/26/2022] [Accepted: 08/27/2022] [Indexed: 01/28/2023]
Abstract
[212Pb]VMT01 is a melanocortin 1 receptor (MC1R) targeted theranostic ligand in clinical development for alpha particle therapy for melanoma. 212Pb has an elementally matched gamma-emitting isotope 203Pb; thus, [203Pb]VMT01 can be used as an imaging surrogate for [212Pb]VMT01. [212Pb]VMT01 human serum stability studies have demonstrated retention of the 212Bi daughter within the chelator following beta emission of parent 212Pb. However, the subsequent alpha emission from the decay of 212Bi into 208Tl results in the generation of free 208Tl. Due to the 10.64-hour half-life of 212Pb, accumulation of free 208Tl in the injectate will occur. The goal of this work is to estimate the human dosimetry for [212Pb]VMT01 and the impact of free 208Tl in the injectate on human tissue absorbed doses. Human [212Pb]VMT01 tissue absorbed doses were estimated from murine [203Pb]VMT01 biodistribution data, and human biodistribution values for 201Tl chloride (a cardiac imaging agent) from published data were used to estimate the dosimetry of free 208Tl. Results indicate that the dose-limiting tissues for [212Pb]VMT01 are the red marrow and the kidneys, with estimated absorbed doses of 1.06 and 8.27 mGyRBE = 5/MBq. The estimated percent increase in absorbed doses from free 208Tl in the injectate is 0.03% and 0.09% to the red marrow and the kidneys, respectively. Absorbed doses from free 208Tl result in a percent increase of no more than 1.2% over [212Pb]VMT01 in any organ or tissue. This latter finding indicates that free 208Tl in the [212Pb]VMT01 injectate will not substantially impact estimated tissue absorbed doses in humans.
Collapse
Affiliation(s)
- Kelly D. Orcutt
- Viewpoint Molecular Targeting, Inc., Coralville, IA 52241, USA
| | | | | | | | | | | | | | | | | | | | - Dijie Liu
- Viewpoint Molecular Targeting, Inc., Coralville, IA 52241, USA
| | - Mengshi Li
- Viewpoint Molecular Targeting, Inc., Coralville, IA 52241, USA
| | | | - Michael K. Schultz
- Viewpoint Molecular Targeting, Inc., Coralville, IA 52241, USA
- Department of Radiology, The University of Iowa, Iowa City, IA 52242, USA
- Department of Radiation Oncology, The University of Iowa, Iowa City, IA 52242, USA
- Departments of Radiology and Radiation Oncology, The University of Iowa, Iowa City, IA 52242, USA
- Correspondence: ; Tel.: +1-(319)-335-8017
| |
Collapse
|
14
|
Li M, Liu D, Lee D, Cheng Y, Baumhover NJ, Marks BM, Sagastume EA, Ballas ZK, Johnson FL, Morris ZS, Schultz MK. Targeted Alpha-Particle Radiotherapy and Immune Checkpoint Inhibitors Induces Cooperative Inhibition on Tumor Growth of Malignant Melanoma. Cancers (Basel) 2021; 13:cancers13153676. [PMID: 34359580 PMCID: PMC8345035 DOI: 10.3390/cancers13153676] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Revised: 07/13/2021] [Accepted: 07/16/2021] [Indexed: 12/23/2022] Open
Abstract
Simple Summary Radiation therapy and immune checkpoint inhibitors (ICIs) have been demonstrated to cooperatively activate adaptive anti-tumor immunity with curative potential in preclinical models of melanoma. Receptor-targeted radionuclide therapy can be systemically injected to selectively deliver ionizing radiation to tumor sites throughout the body, potentially rendering all tumor sites more susceptible to anti-tumor immune response. In this study, we demonstrated the feasibility of delivering alpha-particle radiation to murine melanoma tumors using a 212Pb radiolabeled peptide [212Pb]VMT01 that targets the melanocortin 1 receptor (MC1R). Our data showed anti-tumor cooperation between [212Pb]VMT01 and ICIs in melanoma, mediated by induction of tumor-specific immunity. The immunogenicity of [212Pb]VMT01 in melanoma was also evidenced by enhanced tumor infiltrating lymphocytes and tumor vaccination assays. Abstract Radiotherapy can facilitate the immune recognition of immunologically “cold” tumors and enhance the efficacy of anti-PD-1 and anti-CTLA-4 immune checkpoint inhibitors (ICIs) in melanoma. Systemic administration of receptor-targeted radionuclide therapy has the potential to selectively deliver radionuclides to multiple tumors throughout the body in metastatic settings. By triggering immunologic cell death and increasing the immune susceptibility of surviving tumor cells in these locations, targeted radionuclide therapies may overcome resistance to ICIs and render immunologically “cold” tumors throughout the body responsive to ICIs and immunologically “hot”. Here, we show the anti-tumor cooperation of targeted α-particle radionuclide therapy (α-TRT) and ICIs in preclinical models of melanoma. Melanocortin 1 receptor (MC1R)-targeted radiopeptide [212Pb]VMT01 was employed to deliver α-radiation to melanoma tumors in mice. A single injection of 4.1 MBq [212Pb]VMT01 significantly slowed the tumor growth of B16-F10 melanoma and the combination of [212Pb]VMT01 and ICIs induced a cooperative anti-tumor effect leading to 43% complete tumor response with no sign of malignancy on autopsy. Animals with complete response developed anti-tumor immunity to reject further tumor inoculations. This therapeutic cooperation was completely abolished in RAG1 KO mice, which are deficient in T-cell maturation. In addition, the anti-tumor cooperation was compromised when fractionated [212Pb]VMT01 was used in the combination. We also demonstrated that [212Pb]VMT01 induced immunogenic cell death in tumor vaccination assays and in vitro exposure to [212Pb]VMT01 sensitized immunotolerant melanoma to ICIs treatment in vivo. Enhanced tumor infiltrating CD3+, CD4+, CD8+ lymphocytes were observed following injection of 1.4 MBq [212Pb]VMT01. Overall, we demonstrated anti-tumor cooperation between α-TRT and ICIs in melanoma that is mediated by tumor specific immunity.
Collapse
Affiliation(s)
- Mengshi Li
- Viewpoint Molecular Targeting, Inc., Coralville, IA 52241, USA; (M.L.); (D.L.); (N.J.B.); (B.M.M.); (E.A.S.); (F.L.J.)
- Department of Radiology, University of Iowa, Iowa City, IA 52242, USA;
| | - Dijie Liu
- Viewpoint Molecular Targeting, Inc., Coralville, IA 52241, USA; (M.L.); (D.L.); (N.J.B.); (B.M.M.); (E.A.S.); (F.L.J.)
- Department of Radiology, University of Iowa, Iowa City, IA 52242, USA;
| | - Dongyoul Lee
- Department of Radiology, University of Iowa, Iowa City, IA 52242, USA;
| | - Yinwen Cheng
- Interdisciplinary Graduate Program in Human Toxicology, University of Iowa, Iowa City, IA 52242, USA;
- Department of Pathology, University of Iowa, Iowa City, IA 52242, USA
| | - Nicholas J. Baumhover
- Viewpoint Molecular Targeting, Inc., Coralville, IA 52241, USA; (M.L.); (D.L.); (N.J.B.); (B.M.M.); (E.A.S.); (F.L.J.)
- Department of Radiology, University of Iowa, Iowa City, IA 52242, USA;
| | - Brenna M. Marks
- Viewpoint Molecular Targeting, Inc., Coralville, IA 52241, USA; (M.L.); (D.L.); (N.J.B.); (B.M.M.); (E.A.S.); (F.L.J.)
| | - Edwin A. Sagastume
- Viewpoint Molecular Targeting, Inc., Coralville, IA 52241, USA; (M.L.); (D.L.); (N.J.B.); (B.M.M.); (E.A.S.); (F.L.J.)
| | - Zuhair K. Ballas
- Department of Internal Medicine, University of Iowa, Iowa City, IA 52242, USA;
| | - Frances L. Johnson
- Viewpoint Molecular Targeting, Inc., Coralville, IA 52241, USA; (M.L.); (D.L.); (N.J.B.); (B.M.M.); (E.A.S.); (F.L.J.)
- Department of Internal Medicine, University of Iowa, Iowa City, IA 52242, USA;
| | - Zachary S. Morris
- Department of Human Oncology, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI 53705, USA;
| | - Michael K. Schultz
- Viewpoint Molecular Targeting, Inc., Coralville, IA 52241, USA; (M.L.); (D.L.); (N.J.B.); (B.M.M.); (E.A.S.); (F.L.J.)
- Department of Radiology, University of Iowa, Iowa City, IA 52242, USA;
- Interdisciplinary Graduate Program in Human Toxicology, University of Iowa, Iowa City, IA 52242, USA;
- Department of Pediatrics, University of Iowa, Iowa City, IA 52242, USA
- Department of Chemistry, University of Iowa, Iowa City, IA 52242, USA
- Correspondence: ; Tel.: +1-(865)-356-1861
| |
Collapse
|
15
|
Varmazyad M, Modi MM, Kalen AL, Sarsour EH, Wagner B, Du J, Schultz MK, Buettner GR, Pigge FC, Goswami PC. N-alkyl triphenylvinylpyridinium conjugated dihydroartemisinin perturbs mitochondrial functions resulting in enhanced cancer versus normal cell toxicity. Free Radic Biol Med 2021; 165:421-434. [PMID: 33561488 PMCID: PMC8020572 DOI: 10.1016/j.freeradbiomed.2021.01.050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 01/17/2021] [Accepted: 01/28/2021] [Indexed: 10/22/2022]
Abstract
Dihydroartemisinin (DHA) is an FDA-approved antimalarial drug that has been repurposed for cancer therapy because of its preferential antiproliferative effects on cancer versus normal cells. Mitochondria represent an attractive target for cancer therapy based on their regulatory role in proliferation and cell death. This study investigates whether DHA conjugated to innately fluorescent N-alkyl triphenylvinylpyridinium (TPVP) perturbs mitochondrial functions resulting in a differential toxicity of cancer versus normal cells. TPVP-DHA treatments resulted in a dose-dependent toxicity of human melanoma and pancreatic cancer cells, whereas normal human fibroblasts were resistant to this treatment. TPVP-DHA treatments resulted in a G1-delay of the cancer cell cycle, which was also associated with a significant inhibition of the mTOR-metabolic and ERK1/2-proliferative signaling pathways. TPVP-DHA treatments perturbed mitochondrial functions, which correlated with increases in mitochondrial fission. In summary, TPVP mediated mitochondrial targeting of DHA enhanced cancer cell toxicity by perturbing mitochondrial functions and morphology.
Collapse
Affiliation(s)
| | - Mira M Modi
- Basic Science Department, College of Osteopathic Medicine, Kansas City University, Kansas City, MO, 64106, USA
| | - Amanda L Kalen
- Free Radical and Radiation Biology Division, Department of Radiation Oncology, University of Iowa, Iowa City, IA, 52242, USA
| | - Ehab H Sarsour
- Basic Science Department, College of Osteopathic Medicine, Kansas City University, Kansas City, MO, 64106, USA
| | - Brett Wagner
- Free Radical and Radiation Biology Division, Department of Radiation Oncology, University of Iowa, Iowa City, IA, 52242, USA
| | - Juan Du
- Department of Surgery, University of Iowa, Iowa City, IA, 52242, USA
| | - Michael K Schultz
- Department of Radiology, University of Iowa, Iowa City, IA, 52242, USA
| | - Garry R Buettner
- Free Radical and Radiation Biology Division, Department of Radiation Oncology, University of Iowa, Iowa City, IA, 52242, USA
| | | | - Prabhat C Goswami
- Free Radical and Radiation Biology Division, Department of Radiation Oncology, University of Iowa, Iowa City, IA, 52242, USA.
| |
Collapse
|
16
|
Abstract
Radiation oncologists and nuclear medicine physicians have seen a resurgence in the clinical use of radiopharmaceuticals for the curative or palliative treatment of cancer. To enable the discovery and the development of new targeted radiopharmaceutical treatments, the United States National Cancer Institute has adapted its clinical trial enterprise to accommodate the requirements of a development program with investigational agents that have a radioactive isotope as part of the studied drug product. One change in perspective has been the consideration of investigational radiopharmaceuticals as drugs, with maximum tolerable doses determined by normal organ toxicity frequency like in drug clinical trials. Other changes include new clinical trial enterprise elements for biospecimen handling, adverse event reporting, regulatory conduct, writing services, drug master files, and reporting of patient outcomes. Arising from this enterprise, the study and clinical use of alpha-particle and beta-particle emitters have emerged as an important approach to cancer treatment. Resources allocated to this enterprise have brought forward biomarkers of molecular pathophysiology now used to select treatment or to evaluate clinical performance of radiopharmaceuticals. The clinical use of diagnostic and therapeutic radionuclide pairs is anticipated to accelerate radiopharmaceutical clinical development.
Collapse
Affiliation(s)
- Charles A Kunos
- Cancer Therapy Evaluation Program, National Cancer Institute, Bethesda, MD, USA.
| | - David A Mankoff
- Department of Radiology, University of Pennsylvania, Philadelphia, PA, USA
| | | | | | - Daniel A Pryma
- Department of Radiology, University of Pennsylvania, Philadelphia, PA, USA
| |
Collapse
|
17
|
Falls-Hubert KC, Butler AL, Gui K, Anderson M, Li M, Stolwijk JM, Rodman SN, Solst SR, Tomanek-Chalkley A, Searby CC, Sheffield VC, Sandfort V, Schmidt H, McCormick ML, Wels BR, Allen BG, Buettner GR, Schultz MK, Spitz DR. Disulfiram causes selective hypoxic cancer cell toxicity and radio-chemo-sensitization via redox cycling of copper. Free Radic Biol Med 2020; 150:1-11. [PMID: 32032663 PMCID: PMC7299833 DOI: 10.1016/j.freeradbiomed.2020.01.186] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Revised: 01/30/2020] [Accepted: 01/31/2020] [Indexed: 02/06/2023]
Abstract
Therapies for lung cancer patients initially elicit desirable responses, but the presence of hypoxia and drug resistant cells within tumors ultimately lead to treatment failure. Disulfiram (DSF) is an FDA approved, copper chelating agent that can target oxidative metabolic frailties in cancer vs. normal cells and be repurposed as an adjuvant to cancer therapy. Clonogenic survival assays showed that DSF (50-150 nM) combined with physiological levels of Cu (15 μM CuSO4) was selectively toxic to H292 NSCLC cells vs. normal human bronchial epithelial cells (HBEC). Furthermore, cancer cell toxicity was exacerbated at 1% O2, relative to 4 or 21% O2. This selective toxicity of DSF/Cu was associated with differential Cu ionophore capabilities. DSF/Cu treatment caused a >20-fold increase in cellular Cu in NSCLCs, with nearly two-fold higher Cu present in NSCLCs vs. HBECs and in cancer cells at 1% O2vs. 21% O2. DSF toxicity was shown to be dependent on the retention of Cu as well as oxidative stress mechanisms, including the production of superoxide, peroxide, lipid peroxidation, and mitochondrial damage. DSF was also shown to selectively (relative to HBECs) enhance radiation and chemotherapy-induced NSCLC killing and reduce radiation and chemotherapy resistance in hypoxia. Finally, DSF decreased xenograft tumor growth in vivo when combined with radiation and carboplatin. These results support the hypothesis that DSF could be a promising adjuvant to enhance cancer therapy based on its apparent ability to selectively target fundamental differences in cancer cell oxidative metabolism.
Collapse
Affiliation(s)
- Kelly C Falls-Hubert
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, Carver College of Medicine, University of Iowa, Iowa City, IA, 52242, USA
| | - Aimee L Butler
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, Carver College of Medicine, University of Iowa, Iowa City, IA, 52242, USA
| | - Kai Gui
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, Carver College of Medicine, University of Iowa, Iowa City, IA, 52242, USA
| | - Michael Anderson
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, Carver College of Medicine, University of Iowa, Iowa City, IA, 52242, USA
| | - Mengshi Li
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, Carver College of Medicine, University of Iowa, Iowa City, IA, 52242, USA; Department of Radiology, Carver College of Medicine, University of Iowa, Iowa City, IA, 52242, USA
| | - Jeffrey M Stolwijk
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, Carver College of Medicine, University of Iowa, Iowa City, IA, 52242, USA
| | - Samuel N Rodman
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, Carver College of Medicine, University of Iowa, Iowa City, IA, 52242, USA
| | - Shane R Solst
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, Carver College of Medicine, University of Iowa, Iowa City, IA, 52242, USA
| | - Ann Tomanek-Chalkley
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, Carver College of Medicine, University of Iowa, Iowa City, IA, 52242, USA
| | - Charles C Searby
- Department Pediatrics, University of Iowa, Iowa City, IA, 52242, USA; Department Ophthalmology, University of Iowa, Iowa City, IA, 52242, USA
| | - Val C Sheffield
- Department Pediatrics, University of Iowa, Iowa City, IA, 52242, USA; Department Ophthalmology, University of Iowa, Iowa City, IA, 52242, USA
| | - Vanessa Sandfort
- Gastroenterology and Hepatology, Münster University Hospital (UKM), Münster, Germany
| | - Hartmut Schmidt
- Gastroenterology and Hepatology, Münster University Hospital (UKM), Münster, Germany
| | - Michael L McCormick
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, Carver College of Medicine, University of Iowa, Iowa City, IA, 52242, USA
| | - Brian R Wels
- State Hygienic Lab, University of Iowa, Ankeny, IA, 50023, USA
| | - Bryan G Allen
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, Carver College of Medicine, University of Iowa, Iowa City, IA, 52242, USA
| | - Garry R Buettner
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, Carver College of Medicine, University of Iowa, Iowa City, IA, 52242, USA
| | - Michael K Schultz
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, Carver College of Medicine, University of Iowa, Iowa City, IA, 52242, USA; Department of Radiology, Carver College of Medicine, University of Iowa, Iowa City, IA, 52242, USA; Department Pediatrics, University of Iowa, Iowa City, IA, 52242, USA; Department of Chemistry, University of Iowa, Iowa City, IA, 52241, USA
| | - Douglas R Spitz
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, Carver College of Medicine, University of Iowa, Iowa City, IA, 52242, USA.
| |
Collapse
|
18
|
Li M, Sagastume EE, Lee D, McAlister D, DeGraffenreid AJ, Olewine KR, Graves S, Copping R, Mirzadeh S, Zimmerman BE, Larsen R, Johnson FL, Schultz MK. 203/212Pb Theranostic Radiopharmaceuticals for Image-guided Radionuclide Therapy for Cancer. Curr Med Chem 2020; 27:7003-7031. [PMID: 32720598 PMCID: PMC10613023 DOI: 10.2174/0929867327999200727190423] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 03/25/2020] [Accepted: 04/15/2020] [Indexed: 02/07/2023]
Abstract
Receptor-targeted image-guided Radionuclide Therapy (TRT) is increasingly recognized as a promising approach to cancer treatment. In particular, the potential for clinical translation of receptor-targeted alpha-particle therapy is receiving considerable attention as an approach that can improve outcomes for cancer patients. Higher Linear-energy Transfer (LET) of alpha-particles (compared to beta particles) for this purpose results in an increased incidence of double-strand DNA breaks and improved-localized cancer-cell damage. Recent clinical studies provide compelling evidence that alpha-TRT has the potential to deliver a significantly more potent anti-cancer effect compared with beta-TRT. Generator-produced 212Pb (which decays to alpha emitters 212Bi and 212Po) is a particularly promising radionuclide for receptor-targeted alpha-particle therapy. A second attractive feature that distinguishes 212Pb alpha-TRT from other available radionuclides is the possibility to employ elementallymatched isotope 203Pb as an imaging surrogate in place of the therapeutic radionuclide. As direct non-invasive measurement of alpha-particle emissions cannot be conducted using current medical scanner technology, the imaging surrogate allows for a pharmacologically-inactive determination of the pharmacokinetics and biodistribution of TRT candidate ligands in advance of treatment. Thus, elementally-matched 203Pb labeled radiopharmaceuticals can be used to identify patients who may benefit from 212Pb alpha-TRT and apply appropriate dosimetry and treatment planning in advance of the therapy. In this review, we provide a brief history on the use of these isotopes for cancer therapy; describe the decay and chemical characteristics of 203/212Pb for their use in cancer theranostics and methodologies applied for production and purification of these isotopes for radiopharmaceutical production. In addition, a medical physics and dosimetry perspective is provided that highlights the potential of 212Pb for alpha-TRT and the expected safety for 203Pb surrogate imaging. Recent and current preclinical and clinical studies are presented. The sum of the findings herein and observations presented provide evidence that the 203Pb/212Pb theranostic pair has a promising future for use in radiopharmaceutical theranostic therapies for cancer.
Collapse
Affiliation(s)
- Mengshi Li
- Department of Radiology, The University of Iowa, Iowa City, IA USA
- Viewpoint Molecular Targeting, Inc., Coralville, IA USA
| | | | - Dongyoul Lee
- Interdisciplinary Graduate Program in Human Toxicology, University of Iowa, Iowa City, IA, USA
| | | | | | | | - Stephen Graves
- Department of Radiology, The University of Iowa, Iowa City, IA USA
| | - Roy Copping
- Oak Ridge National Laboratory, The US Department of Energy, Oak Ridge TN USA
| | - Saed Mirzadeh
- Oak Ridge National Laboratory, The US Department of Energy, Oak Ridge TN USA
| | - Brian E. Zimmerman
- The National Institute of Standards and Technology, Gaithersburg, MD, USA
| | | | - Frances L. Johnson
- Viewpoint Molecular Targeting, Inc., Coralville, IA USA
- Department of Internal Medicine, Carver College of Medicine, The University of Iowa, Iowa City, Iowa USA
| | - Michael K. Schultz
- Department of Radiology, The University of Iowa, Iowa City, IA USA
- Viewpoint Molecular Targeting, Inc., Coralville, IA USA
- Interdisciplinary Graduate Program in Human Toxicology, University of Iowa, Iowa City, IA, USA
- Department of Chemistry, The University of Iowa, Iowa City, IA, USA
| |
Collapse
|
19
|
Li M, Liu D, Lee D, Kapoor S, Gibson-Corley KN, Quinn TP, Sagastume EA, Mott SL, Walsh SA, Acevedo MR, Johnson FL, Schultz MK. Enhancing the Efficacy of Melanocortin 1 Receptor-Targeted Radiotherapy by Pharmacologically Upregulating the Receptor in Metastatic Melanoma. Mol Pharm 2019; 16:3904-3915. [PMID: 31318566 DOI: 10.1021/acs.molpharmaceut.9b00512] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Melanocortin 1 receptor (MC1R) is under investigation as a target for drug delivery for metastatic melanoma therapy and imaging. The purpose of this study was to determine the potential of using BRAF inhibitors (BRAFi) and histone deacetylase inhibitors (HDACi) to enhance the delivery of MC1R-targeted radiolabeled peptide ([212Pb]DOTA-MC1L) by pharmacologically upregulating the MC1R expression in metastatic melanoma cells and tumors. MC1R expression was analyzed in de-identified melanoma biopsies by immunohistochemical staining. Upregulation of MC1R expression was determined in BRAFV600E cells (A2058) and BRAF wild-type melanoma cells (MEWO) by quantitative real-time polymerase chain reaction, flow cytometry, and receptor-ligand binding assays. The role of microphthalmia-associated transcription factor (MITF) in the upregulation of MC1R was also examined in A2058 and MEWO cells. The effectiveness of [212Pb]DOTA-MC1L α-particle radiotherapy in combination with BRAFi and/or HDACi was determined in athymic nu/nu mice bearing A2058 and MEWO human melanoma xenografts. High expression of MC1R was observed in situ in clinical melanoma biopsies. BRAFi and HDACi significantly increased the MC1R expression (up to 10-fold in mRNA and 4-fold in protein levels) via MITF-dependent pathways, and this increase led to enhanced ligand binding on the cell surface. Inhibition of MITF expression antagonized the upregulation of MC1R in both BRAFV600E and BRAFWT cells. Combining [212Pb]DOTA-MC1L with BRAFi and/or HDACi improved the tumor response by increasing the delivery of 212Pb α-particle emissions to melanoma tumors via augmented MC1R expression. These data suggest that FDA-approved HDACi and BRAFi could improve the effectiveness of MC1R-targeted therapies by enhancing drug delivery via upregulated MC1R.
Collapse
Affiliation(s)
| | | | | | | | | | - Thomas P Quinn
- Department of Biochemistry , University of Missouri , Columbia , Missouri 65211 , United States
| | - Edwin A Sagastume
- Viewpoint Molecular Targeting, Inc. , Coralville , Iowa 52241 , United States
| | | | | | | | - Frances L Johnson
- Viewpoint Molecular Targeting, Inc. , Coralville , Iowa 52241 , United States
| | - Michael K Schultz
- Viewpoint Molecular Targeting, Inc. , Coralville , Iowa 52241 , United States
| |
Collapse
|
20
|
Goel A, Nishikawa K, Futaya E, Poylak I, Holt R, Li M, Sagastum E, Marks B, Bossler AD, Johnson FL, Schultz MK, Goda H, Okada H, Orcutt K, Abe G, Bloom K. Abstract LB-230: Quantitative immunohistochemistry for melanocortin 1 receptor using phosphor integrated dots. Cancer Res 2019. [DOI: 10.1158/1538-7445.am2019-lb-230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Visual scoring of biomarkers by immunohistochemistry (IHC) on formalin-fixed paraffin embedded tissues constitutes a major part of histopathologic diagnosis and staging of several cancers. To improve sensitivity and linearity of IHC methods, we have developed a quantitative IHC technique using streptavidin coated phosphor integrated dot (PID) fluorescent nanoparticles (Gonda et al, Scientific Reports, 2017). In retrospective analysis of clinically established biomarkers (i.e., PD-L1, HER2, CSF-1R), IHC-PID has provided high-sensitivity quantitative detection of target proteins with a broad dynamic range. The present study examines the utility of IHC-PID in the biomarker discovery and validation process by evaluating melanocortin subtype 1 receptor (MC1R) in cell lines and clinical biopsy samples. MC1R is currently under investigation as a potential diagnostic and therapeutic target for malignant melanoma, a lethal cancer with poor long-term prognosis. MC1R is an endocytic cell-surface G-protein coupled receptor that exhibits relatively high expression in malignant melanoma tumors vs. normal tissues. Notably, current melanoma therapies, including MAPKi (e.g., vemurafenib, dabrafenib) increase MC1R expression pharmacologically on melanoma cells (unpublished results). MC1R expression was determined in cell lines by standard radio-ligand binding assay (125I-NDP-α-MSH). The SK-Mel-28 cell line showed 5-6 fold increased expression of endogenous MC1R when compared to the A375 cell line. Formalin fixed pellets of these two cell lines were used for analytical validation of PID-IHC. By utilizing dedicated image-processing algorithms, the readout of average PID score/cell was determined to be 285 and 98, for SK-Mel-28 and A375 cell lines, respectively. To confirm the increase in sensitivity with the PID technology, enabling quantitative IHC and improved detection of MC1R, de-identified melanoma samples from varying sites were collected by surgical biopsy at The University of Iowa Hospitals and Clinics and scored by a pathologist. Sister sections were stained by conventional IHC or IHC-PID. For IHC-PID, sections were counter stained by hematoxylin; tumor regions were hand annotated by a pathologist; and fluorescent images in 5 microscopic fields were captured and analyzed. Background PID threshold was determined by using no-primary antibody as controls. IHC-PID was performed on MS0759 (T1b N0 M0), MS0045 (T3a N1a M0) and MS0868 (T4b N3 M1a) samples and showed average PID score/cell of 217±38, 68±12, and 160±21, respectively. Ongoing studies are expanding on IHC-PID use to assess MC1R expression on a clinical melanoma panel (n=20) in late stage patients undergoing pharmacological interventions including MAPKi. The overall goal of this project is to develop PID-based quantitative IHC to support the development of MC1R as an imaging biomarker for patient stratification and monitoring clinical response to MC1R-targeted radionuclide therapy for malignant melanoma.
Note: This abstract was not presented at the meeting.
Citation Format: Apollina Goel, Kenji Nishikawa, Etsuko Futaya, Ildiko Poylak, Robert Holt, Mengshi Li, Edwin Sagastum, Brenna Marks, Aaron D. Bossler, Frances L. Johnson, Michael K. Schultz, Hideki Goda, Hisatake Okada, Kelly Orcutt, George Abe, Kenneth Bloom. Quantitative immunohistochemistry for melanocortin 1 receptor using phosphor integrated dots [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr LB-230.
Collapse
Affiliation(s)
| | - Kenji Nishikawa
- 2Konica Minolta Inc., Bio Health Care Business Development Division, Tokyo, Japan
| | - Etsuko Futaya
- 2Konica Minolta Inc., Bio Health Care Business Development Division, Tokyo, Japan
| | | | | | | | | | | | | | | | | | - Hideki Goda
- 2Konica Minolta Inc., Bio Health Care Business Development Division, Tokyo, Japan
| | - Hisatake Okada
- 2Konica Minolta Inc., Bio Health Care Business Development Division, Tokyo, Japan
| | | | | | | |
Collapse
|
21
|
Ghai A, Singh B, Li M, Daniels TA, Coelho R, Orcutt K, Watkins GL, Norenberg JP, Cvet D, Schultz MK. Optimizing the radiosynthesis of [ 68Ga]DOTA-MLN6907 peptide containing three disulfide cyclization bonds - a GCC specific chelate for clinical radiopharmaceuticals. Appl Radiat Isot 2018; 140:333-341. [PMID: 30138815 DOI: 10.1016/j.apradiso.2018.08.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Revised: 07/17/2018] [Accepted: 08/08/2018] [Indexed: 10/28/2022]
Abstract
In the present study, the effect of radiolabeling conditions on radiolabeling efficiency and achievable specific activity of a DOTA-conjugated highly-lipophilic peptide containing three disulfide cyclization bonds was examined. The peptide is designed to bind specifically (with high affinity) to cell-surface receptor guanylyl cyclase C (GCC), which is universally expressed by colorectal cancer cells. The effect of systematic variation of chemical parameters pH, mass of peptide, acetate buffer concentration (ionic strength), and inclusion of ethanol in the radiolabeling reaction vessel on achievable specific activity and labeling efficiency was examined. In addition, a unique approach to acetone-based elution of 68Ga from an initial cation-exchange pre-concentration column is introduced, which improved radiochemical yield and radiochemical purity. For the evaluation of the acetone-based method, two different post-radiolabeling reverse-phase (C18) approaches to purify the final radiolabeled peptide were tested. These results revealed the potential for peptide degradation via the cleavage of disulfide cyclization bonds to form free thiols when using one of these C18 cartridges. The final optimized procedure enabled radiolabeling efficiency of greater than 99% and specific activity greater than 35 MBq/nmole in less than 30 min. The optimized parameters were amenable to the use of an automated 68Ge/68Ga generator and fluid-handling system for clinical production of the GCC receptor-specific [68Ga]DOTA-MLN6907 peptide. The chemical characteristics of individual peptides govern the most appropriate radiolabeling conditions for the preparation of radiopharmaceuticals.
Collapse
Affiliation(s)
- Anchal Ghai
- Department of Nuclear Medicine, Postgraduate Institute of Medical Education & Research, Sector 12, Chandigarh 160012, India
| | - Baljinder Singh
- Department of Nuclear Medicine, Postgraduate Institute of Medical Education & Research, Sector 12, Chandigarh 160012, India
| | - Mengshi Li
- Department of Radiology, The University of Iowa, 200 Hawkins Drive, Iowa City, IA 52242, USA; Departments of Radiation Oncology (Free Radical and Radiation Biology Program), Pediatrics, and Chemistry, and the Interdisciplinary Program in Human Toxicology, The University of Iowa, 500 N Road, ML B180, FRRB, Iowa City, IA, USA
| | - Tamara A Daniels
- Radiopharmaceutical Sciences, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, USA
| | | | - Kelly Orcutt
- InviCRO, LLC, 27 Drydock Avenue, Boston, MA 02210 , USA
| | - G Leonard Watkins
- Department of Radiology, The University of Iowa, 200 Hawkins Drive, Iowa City, IA 52242, USA
| | - Jeffrey P Norenberg
- Radiopharmaceutical Sciences, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, USA
| | - Donna Cvet
- Takeda Pharmaceuticals, 40 Landsdowne Street, Cambridge, MA 02139, USA
| | - Michael K Schultz
- Department of Radiology, The University of Iowa, 200 Hawkins Drive, Iowa City, IA 52242, USA; Departments of Radiation Oncology (Free Radical and Radiation Biology Program), Pediatrics, and Chemistry, and the Interdisciplinary Program in Human Toxicology, The University of Iowa, 500 N Road, ML B180, FRRB, Iowa City, IA, USA.
| |
Collapse
|
22
|
Schultz MK, Gentzel R, Usenovic M, Gretzula C, Ware C, Parmentier-Batteur S, Schachter JB, Zariwala HA. Pharmacogenetic neuronal stimulation increases human tau pathology and trans-synaptic spread of tau to distal brain regions in mice. Neurobiol Dis 2018; 118:161-176. [PMID: 30049665 DOI: 10.1016/j.nbd.2018.07.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Revised: 06/15/2018] [Accepted: 07/04/2018] [Indexed: 12/26/2022] Open
Abstract
In Alzheimer's Disease (AD), tau pathology has a spatiotemporally distinct pattern of progressive spread along anatomically connected neural pathways. Extracellular tau in the brain interstitial space increases in response to neuronal activity suggesting that neural activity may also drive pathogenic tau spread. Here we tested the hypothesis that neuronal activity drives human Tau (hTau) release and trans-synaptic spread to neuroanatomically connected regions. We used AAV to overexpress wild type full-length hTau and an excitatory DREADD (Designer Receptors Exclusively Activated by a Designer Drug) in mouse primary hippocampal cultures and determined that excitatory stimulation with the DREADD ligand clozapine N-oxide (CNO) promoted extracellular hTau release. We translated this approach to an in vivo model and used AAV to express hTau and the excitatory DREADD in the ventral hippocampus of wild type mice, P301L hTau-expressing mice, or tau knockout mice. Six to eight weeks following AAV injection, we determined that CNO treatment in DREADD-expressing mice resulted in increased hTau pathology and hTau spread to distal brain regions compared to unstimulated controls (CNO in non-DREADD mice, or vehicle in DREADD mice). The results highlight a potentially disease relevant exacerbation of tau pathology in response to elevated neuronal activity. This model underscores the propensity of non-mutant hTau to undergo neuronal spreading, as seen in AD. The model can translate to other preclinical species and can be used to evaluate modes of tau transmission and test the efficacy of therapeutic approaches that target tau or hyperexcitability.
Collapse
Affiliation(s)
- M K Schultz
- Pharmacology, Merck & Co., Inc., West Point, PA, USA
| | - R Gentzel
- Neuroscience, Merck & Co., Inc., West Point, PA, USA
| | - M Usenovic
- Neuroscience, Merck & Co., Inc., West Point, PA, USA
| | - C Gretzula
- Neuroscience, Merck & Co., Inc., West Point, PA, USA
| | - C Ware
- Neuroscience, Merck & Co., Inc., Boston, MA, USA
| | | | - J B Schachter
- Neuroscience, Merck & Co., Inc., West Point, PA, USA
| | - H A Zariwala
- Pharmacology, Merck & Co., Inc., West Point, PA, USA.
| |
Collapse
|
23
|
Lee D, Li M, Bednarz B, Schultz MK. Modeling Cell and Tumor-Metastasis Dosimetry with the Particle and Heavy Ion Transport Code System (PHITS) Software for Targeted Alpha-Particle Radionuclide Therapy. Radiat Res 2018; 190:236-247. [PMID: 29944461 DOI: 10.1667/rr15081.1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The use of targeted radionuclide therapy for cancer is on the rise. While beta-particle-emitting radionuclides have been extensively explored for targeted radionuclide therapy, alpha-particle-emitting radionuclides are emerging as effective alternatives. In this context, fundamental understanding of the interactions and dosimetry of these emitted particles with cells in the tumor microenvironment is critical to ascertaining the potential of alpha-particle-emitting radionuclides. One important parameter that can be used to assess these metrics is the S-value. In this study, we characterized several alpha-particle-emitting radionuclides (and their associated radionuclide progeny) regarding S-values in the cellular and tumor-metastasis environments. The Particle and Heavy Ion Transport code System (PHITS) was used to obtain S-values via Monte Carlo simulation for cell and tumor metastasis resulting from interactions with the alpha-particle-emitting radionuclides, lead-212 (212Pb), actinium-225 (225Ac) and bismuth-213 (213Bi); these values were compared to the beta-particle-emitting radionuclides yttrium-90 (90Y) and lutetium-177 (177Lu) and an Auger-electron-emitting radionuclide indium-111 (111In). The effect of cellular internalization on S-value was explored at increasing degree of internalization for each radionuclide. This aspect of S-value determination was further explored in a cell line-specific fashion for six different cancer cell lines based on the cell dimensions obtained by confocal microscopy. S-values from PHITS were in good agreement with MIRDcell S-values (cellular S-values) and the values found by Hindié et al. (tumor S-values). In the cellular model, 212Pb and 213Bi decay series produced S-values that were 50- to 120-fold higher than 177Lu, while 225Ac decay series analysis suggested S-values that were 240- to 520-fold higher than 177Lu. S-values arising with 100% cellular internalization were two- to sixfold higher for the nucleus when compared to 0% internalization. The tumor dosimetry model defines the relative merit of radionuclides and suggests alpha particles may be effective for large tumors as well as small tumor metastases. These results from PHITS modeling substantiate emerging evidence that alpha-particle-emitting radionuclides may be an effective alternative to beta-particle-emitting radionuclides for targeted radionuclide therapy due to preferred dose-deposition profiles in the cellular and tumor metastasis context. These results further suggest that internalization of alpha-particle-emitting radionuclides via radiolabeled ligands may increase the relative biological effectiveness of radiotherapeutics.
Collapse
Affiliation(s)
- Dongyoul Lee
- a Interdisciplinary Graduate Program in Human Toxicology, The University of Iowa, Iowa City, Iowa
| | - Mengshi Li
- a Interdisciplinary Graduate Program in Human Toxicology, The University of Iowa, Iowa City, Iowa
| | - Bryan Bednarz
- b Department of Medical Physics, University of Wisconsin, Madison, Wisconsin
| | - Michael K Schultz
- a Interdisciplinary Graduate Program in Human Toxicology, The University of Iowa, Iowa City, Iowa.,c Stead Family Department of Pediatrics, Carver College of Medicine, The University of Iowa, Iowa City, Iowa.,d Department of Radiology, Carver College of Medicine, The University of Iowa, Iowa City, Iowa.,e Department of Radiation Oncology (Free Radical and Radiation Biology Program), Carver College of Medicine, The University of Iowa, Iowa City, Iowa.,f Department of Chemistry, The University of Iowa, Iowa City, Iowa.,g Viewpoint Molecular Targeting, LLC, Coralville, Iowa
| |
Collapse
|
24
|
Menda Y, Madsen MT, O'Dorisio TM, Sunderland JJ, Watkins GL, Dillon JS, Mott SL, Schultz MK, Zamba GKD, Bushnell DL, O'Dorisio MS. 90Y-DOTATOC Dosimetry-Based Personalized Peptide Receptor Radionuclide Therapy. J Nucl Med 2018. [PMID: 29523629 DOI: 10.2967/jnumed.117.202903] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Pretherapy PET with 86Y-DOTATOC is considered the ideal dosimetry protocol for 90Y-DOTATOC therapy; however, its cost, limited availability, and need for infusion of amino acids to mimic the therapy administration limit its use in the clinical setting. The goal of this study was to develop a dosimetric method for 90Y-DOTATOC using 90Y-DOTATOC PET/CT and bremsstrahlung SPECT/CT and to determine whether dosimetry-based administered activities differ significantly from standard administered activities. Methods: This was a prospective phase 2 trial of 90Y-DOTATOC therapy in patients with somatostatin receptor-positive tumors. 90Y-DOTATOC was given in 3 cycles 6-8 wk apart. In the first cycle of therapy, adults received 4.4 GBq and children received 1.85 GBq/m2; the subsequent administered activities were adjusted according to the dosimetry of the preceding cycle so as not to exceed a total kidney dose of 23 Gy and bone marrow dose of 2 Gy. The radiation dose to the kidneys was determined from serial imaging sessions consisting of time-of-flight 90Y-DOTATOC PET/CT at 5 h after therapy and 90Y-DOTATOC bremsstrahlung SPECT/CT at 6, 24, 48, and 72 h. The PET/CT data were used to measure the absolute concentration of 90Y-DOTATOC and to calibrate the bremsstrahlung SPECT kidney clearance data. The radiation dose to the kidneys was determined by multiplying the time-integrated activity (from the fitted biexponential curve of renal clearance of 90Y-DOTATOC) with the energy emitted per decay, divided by the mass of the kidneys. Results: The radiation dose to the kidneys per cycle of 90Y-DOTATOC therapy was highly variable among patients, ranging from 0.32 to 3.0 mGy/MBq. In 17 (85%) of the 20 adult patients who received the second and the third treatment cycles of 90Y-DOTATOC, the administered activity was modified by at least 20% from the starting administered activity. Conclusion: Renal dosimetry of 90Y-DOTATOC is feasible using 90Y-DOTATOC time-of-flight PET/CT and bremsstrahlung SPECT/CT and has a significant impact on the administered activity in treatment cycles.
Collapse
Affiliation(s)
- Yusuf Menda
- Department of Radiology, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Mark T Madsen
- Department of Radiology, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Thomas M O'Dorisio
- Department of Internal Medicine, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - John J Sunderland
- Department of Radiology, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - G Leonard Watkins
- Department of Radiology, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Joseph S Dillon
- Department of Internal Medicine, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Sarah L Mott
- Holden Comprehensive Cancer Center, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Michael K Schultz
- Department of Radiology, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Gideon K D Zamba
- Department of Biostatistics, College of Public Health, University of Iowa, Iowa City, Iowa; and
| | - David L Bushnell
- Department of Radiology, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - M Sue O'Dorisio
- Department of Pediatrics, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa
| |
Collapse
|
25
|
Rosenblum J, Nelson AW, Ruyle B, Schultz MK, Ryan JN, Linden KG. Temporal characterization of flowback and produced water quality from a hydraulically fractured oil and gas well. Sci Total Environ 2017; 596-597:369-377. [PMID: 28448913 DOI: 10.1016/j.scitotenv.2017.03.294] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Revised: 03/31/2017] [Accepted: 03/31/2017] [Indexed: 05/23/2023]
Abstract
This study examined water quality, naturally-occurring radioactive materials (NORM), major ions, trace metals, and well flow data for water used and produced from start-up to operation of an oil and gas producing hydraulically-fractured well (horizontal) in the Denver-Julesburg (DJ) Basin in northeastern Colorado. Analysis was conducted on the groundwater used to make the fracturing fluid, the fracturing fluid itself, and nine flowback/produced water samples over 220days of operation. The chemical oxygen demand of the wastewater produced during operation decreased from 8200 to 2500mg/L, while the total dissolved solids (TDS) increased in this same period from 14,200 to roughly 19,000mg/L. NORM, trace metals, and major ion levels were generally correlated with TDS, and were lower than other shale basins (e.g. Marcellus and Bakken). Although at lower levels, the salinity and its origin appear to be the result of a similar mechanism to that of other shale basins when comparing Cl/Br, Na/Br, and Mg/Br ratios. Volumes of returned wastewater were low, with only 3% of the volume injected (11millionliters) returning as flowback by day 15 and 30% returning by day 220. Low levels of TDS indicate a potentially treatment-amenable wastewater, but low volumes of flowback could limit onsite reuse in the DJ Basin. These results offer insight into the temporal water quality changes in the days and months following flowback, along with considerations and implications for water reuse in future hydraulic fracturing or for environmental discharge.
Collapse
Affiliation(s)
- James Rosenblum
- Department of Civil, Environmental, and Architectural Engineering, University of Colorado, UCB 607, Boulder, CO 80309, USA
| | - Andrew W Nelson
- Interdisciplinary Human Toxicology Program, University of Iowa, Iowa City, IA 52242, USA
| | - Bridger Ruyle
- Department of Civil, Environmental, and Architectural Engineering, University of Colorado, UCB 607, Boulder, CO 80309, USA
| | - Michael K Schultz
- Interdisciplinary Human Toxicology Program, University of Iowa, Iowa City, IA 52242, USA; Departments of Radiology and Radiation Oncology, Free Radical and Radiation Biology Program, Medical Scientist Training Program, University of Iowa, Iowa City, IA 52240, USA
| | - Joseph N Ryan
- Department of Civil, Environmental, and Architectural Engineering, University of Colorado, UCB 607, Boulder, CO 80309, USA
| | - Karl G Linden
- Department of Civil, Environmental, and Architectural Engineering, University of Colorado, UCB 607, Boulder, CO 80309, USA.
| |
Collapse
|
26
|
Li M, Zhang X, Quinn TP, Lee D, Liu D, Kunkel F, Zimmerman BE, McAlister D, Olewein K, Menda Y, Mirzadeh S, Copping R, Johnson FL, Schultz MK. Automated cassette-based production of high specific activity [ 203/212Pb]peptide-based theranostic radiopharmaceuticals for image-guided radionuclide therapy for cancer. Appl Radiat Isot 2017; 127:52-60. [PMID: 28521118 PMCID: PMC6295910 DOI: 10.1016/j.apradiso.2017.05.006] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Revised: 04/29/2017] [Accepted: 05/06/2017] [Indexed: 01/28/2023]
Abstract
A method for preparation of Pb-212 and Pb-203 labeled chelator-modified peptide-based radiopharmaceuticals for cancer imaging and radionuclide therapy has been developed and adapted for automated clinical production. Pre-concentration and isolation of radioactive Pb2+ from interfering metals in dilute hydrochloric acid was optimized using a commercially-available Pb-specific chromatography resin packed in disposable plastic columns. The pre-concentrated radioactive Pb2+ is eluted in NaOAc buffer directly to the reaction vessel containing chelator-modified peptides. Radiolabeling was found to proceed efficiently at 85°C (45min; pH 5.5). The specific activity of radiolabeled conjugates was optimized by separation of radiolabeled conjugates from unlabeled peptide via HPLC. Preservation of bioactivity was confirmed by in vivo biodistribution of Pb-203 and Pb-212 labeled peptides in melanoma-tumor-bearing mice. The approach has been found to be robustly adaptable to automation and a cassette-based fluid-handling system (Modular Lab Pharm Tracer) has been customized for clinical radiopharmaceutical production. Our findings demonstrate that the Pb-203/Pb-212 combination is a promising elementally-matched radionuclide pair for image-guided radionuclide therapy for melanoma, neuroendocrine tumors, and potentially other cancers.
Collapse
Affiliation(s)
- Mengshi Li
- Interdisciplinary Graduate Program in Human Toxicology, University of Iowa, Iowa City, IA, USA.
| | - Xiuli Zhang
- Department of Biochemistry, University of Missouri, Columbia, MO USA
| | - Thomas P Quinn
- Department of Biochemistry, University of Missouri, Columbia, MO USA
| | - Dongyoul Lee
- Interdisciplinary Graduate Program in Human Toxicology, University of Iowa, Iowa City, IA, USA
| | - Dijie Liu
- Stead Family Department of Pediatrics, University of Iowa, Iowa City, IA, USA
| | - Falk Kunkel
- Eckert & Ziegler Radiopharma GmbH, Berlin, Germany
| | - Brian E Zimmerman
- National Institute of Standards and Technology, Gaithersburg, MD, USA
| | | | | | - Yusuf Menda
- Department of Radiology, The University of Iowa, Iowa City, IA, USA
| | - Saed Mirzadeh
- Oak Ridge National Laboratory, The US Department of Energy, Oak Ridge, TN, USA
| | - Roy Copping
- Oak Ridge National Laboratory, The US Department of Energy, Oak Ridge, TN, USA
| | - Frances L Johnson
- Viewpoint Molecular Targeting, LLC, Coralville, IA, USA; Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - Michael K Schultz
- Interdisciplinary Graduate Program in Human Toxicology, University of Iowa, Iowa City, IA, USA; Stead Family Department of Pediatrics, University of Iowa, Iowa City, IA, USA; Department of Radiology, The University of Iowa, Iowa City, IA, USA; Viewpoint Molecular Targeting, LLC, Coralville, IA, USA; Department of Radiation Oncology (Free Radical and Radiation Biology Program), Carver College of Medicine, University of Iowa, Iowa City, IA, USA; Department of Chemistry, University of Iowa, Iowa City, IA, USA.
| |
Collapse
|
27
|
Schoenfeld JD, Sibenaller ZA, Mapuskar KA, Wagner BA, Cramer-Morales KL, Furqan M, Sandhu S, Carlisle TL, Smith MC, Abu Hejleh T, Berg DJ, Zhang J, Keech J, Parekh KR, Bhatia S, Monga V, Bodeker KL, Ahmann L, Vollstedt S, Brown H, Kauffman EPS, Schall ME, Hohl RJ, Clamon GH, Greenlee JD, Howard MA, Schultz MK, Smith BJ, Riley DP, Domann FE, Cullen JJ, Buettner GR, Buatti JM, Spitz DR, Allen BG. O 2⋅- and H 2O 2-Mediated Disruption of Fe Metabolism Causes the Differential Susceptibility of NSCLC and GBM Cancer Cells to Pharmacological Ascorbate. Cancer Cell 2017; 32:268. [PMID: 28810149 DOI: 10.1016/j.ccell.2017.07.008] [Citation(s) in RCA: 75] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
28
|
May D, Nelson AN, Schultz MK. Quantitation of lead-210 ( 210Pb) using lead-203 ( 203Pb) as a "Massless" yield tracer. J Environ Radioact 2017; 171:93-98. [PMID: 28213127 PMCID: PMC6785750 DOI: 10.1016/j.jenvrad.2017.02.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2016] [Revised: 01/30/2017] [Accepted: 02/03/2017] [Indexed: 06/06/2023]
Abstract
Determination of Pb-210 (210Pb) in aqueous solution is a common radioanalytical challenge in environmental science. Widely used methods for undertaking these analyses (e.g., ASTM D7535) rely on the use of stable lead (Pb) as a yield tracer that takes into account losses of 210Pb that inevitably occur during elemental/radiochemical separations of the procedures. Although effective, these methods introduce technical challenges that can be difficult to track and potentially introduce uncertainty that can be difficult to quantify. Examples of these challenges include interference from endogenous stable Pb in complex sample matrices; contamination of stable Pb carrier with 210Pb; and high detection limits due to counting efficiency limitations. We hypothesized that many of these challenges could be avoided by the use of the electron-capture, gamma-emitting isotope, 203Pb as a chemical yield tracer in the analysis of 210Pb. A series of experiments were performed to evaluate the efficacy of 203Pb as a tracer. Four different matrices were analyzed, including a complex matrix (hydraulic-fracturing produced fluids); and samples comprising less complicated matrices (i.e., river water, deionized water, and tap water). Separation techniques and counting methodologies were also compared and optimized. Due to a relatively short-half life (52 h), 203Pb tracer is effectively massless for the purposes of chemical separations, allowing for reduced chromatography column resin bed volumes. Because 203Pb is a gamma emitter (279 keV; 81% intensity), recovery can be determined non-destructively in a variety of matrices, including liquid scintillation cocktail. The use of liquid scintillation as a counting methodology allowed for determination of 210Pb activities via 210Pb or 210Po; and recoveries of greater than 90% are routinely achievable using this approach. The improved method for the analysis of 210Pb in aqueous matrices allows for the analysis of complex matrices, at reduced cost, while providing greater counting flexibility in achieving acceptable detections limits.
Collapse
Affiliation(s)
- D May
- State Hygienic Laboratory at the University of Iowa, Coralville, IA 52241, United States; Interdisciplinary Human Toxicology Program, University of Iowa, Iowa City, IA 52242, United States.
| | - A N Nelson
- Interdisciplinary Human Toxicology Program, University of Iowa, Iowa City, IA 52242, United States; Department of Chemistry, University of Iowa, Iowa City, IA 52242, United States.
| | - M K Schultz
- Interdisciplinary Human Toxicology Program, University of Iowa, Iowa City, IA 52242, United States; Department of Chemistry, University of Iowa, Iowa City, IA 52242, United States; Departments of Radiology and Radiation Oncology, Free Radical and Radiation Biology Program, University of Iowa, Iowa City, IA 52242, United States.
| |
Collapse
|
29
|
Schoenfeld JD, Sibenaller ZA, Mapuskar KA, Wagner BA, Cramer-Morales KL, Furqan M, Sandhu S, Carlisle TL, Smith MC, Abu Hejleh T, Berg DJ, Zhang J, Keech J, Parekh KR, Bhatia S, Monga V, Bodeker KL, Ahmann L, Vollstedt S, Brown H, Shanahan Kauffman EP, Schall ME, Hohl RJ, Clamon GH, Greenlee JD, Howard MA, Schultz MK, Smith BJ, Riley DP, Domann FE, Cullen JJ, Buettner GR, Buatti JM, Spitz DR, Allen BG. O 2⋅- and H 2O 2-Mediated Disruption of Fe Metabolism Causes the Differential Susceptibility of NSCLC and GBM Cancer Cells to Pharmacological Ascorbate. Cancer Cell 2017; 31:487-500.e8. [PMID: 28366679 PMCID: PMC5497844 DOI: 10.1016/j.ccell.2017.02.018] [Citation(s) in RCA: 247] [Impact Index Per Article: 35.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Revised: 12/13/2016] [Accepted: 02/27/2017] [Indexed: 01/10/2023]
Abstract
Pharmacological ascorbate has been proposed as a potential anti-cancer agent when combined with radiation and chemotherapy. The anti-cancer effects of ascorbate are hypothesized to involve the autoxidation of ascorbate leading to increased steady-state levels of H2O2; however, the mechanism(s) for cancer cell-selective toxicity remain unknown. The current study shows that alterations in cancer cell mitochondrial oxidative metabolism resulting in increased levels of O2⋅- and H2O2 are capable of disrupting intracellular iron metabolism, thereby selectively sensitizing non-small-cell lung cancer (NSCLC) and glioblastoma (GBM) cells to ascorbate through pro-oxidant chemistry involving redox-active labile iron and H2O2. In addition, preclinical studies and clinical trials demonstrate the feasibility, selective toxicity, tolerability, and potential efficacy of pharmacological ascorbate in GBM and NSCLC therapy.
Collapse
Affiliation(s)
- Joshua D Schoenfeld
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Zita A Sibenaller
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Kranti A Mapuskar
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Brett A Wagner
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Kimberly L Cramer-Morales
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Muhammad Furqan
- Division of Hematology, Oncology, and Blood & Marrow Transplantation, Department of Internal Medicine, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Sonia Sandhu
- Division of Hematology, Oncology, and Blood & Marrow Transplantation, Department of Internal Medicine, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Thomas L Carlisle
- Division of Hematology, Oncology, and Blood & Marrow Transplantation, Department of Internal Medicine, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Mark C Smith
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Taher Abu Hejleh
- Division of Hematology, Oncology, and Blood & Marrow Transplantation, Department of Internal Medicine, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Daniel J Berg
- Division of Hematology, Oncology, and Blood & Marrow Transplantation, Department of Internal Medicine, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Jun Zhang
- Division of Hematology, Oncology, and Blood & Marrow Transplantation, Department of Internal Medicine, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - John Keech
- Department of Surgery, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Kalpaj R Parekh
- Department of Surgery, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Sudershan Bhatia
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Varun Monga
- Division of Hematology, Oncology, and Blood & Marrow Transplantation, Department of Internal Medicine, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Kellie L Bodeker
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Logan Ahmann
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Sandy Vollstedt
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Heather Brown
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Erin P Shanahan Kauffman
- Division of Hematology, Oncology, and Blood & Marrow Transplantation, Department of Internal Medicine, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Mary E Schall
- Division of Hematology, Oncology, and Blood & Marrow Transplantation, Department of Internal Medicine, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Ray J Hohl
- Division of Hematology, Oncology, and Blood & Marrow Transplantation, Department of Internal Medicine, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Gerald H Clamon
- Division of Hematology, Oncology, and Blood & Marrow Transplantation, Department of Internal Medicine, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Jeremy D Greenlee
- Department of Neurosurgery, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Matthew A Howard
- Department of Neurosurgery, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Michael K Schultz
- Department of Radiology, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Brian J Smith
- Departmet of Biostatistics, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | | | - Frederick E Domann
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Joseph J Cullen
- Department of Surgery, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Garry R Buettner
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - John M Buatti
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | - Douglas R Spitz
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA.
| | - Bryan G Allen
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA.
| |
Collapse
|
30
|
Nelson AW, Eitrheim ES, Knight AW, May D, Wichman MD, Forbes TZ, Schultz MK. Polonium-210 accumulates in a lake receiving coal mine discharges-anthropogenic or natural? J Environ Radioact 2017; 167:211-221. [PMID: 27914777 DOI: 10.1016/j.jenvrad.2016.10.023] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2016] [Revised: 10/21/2016] [Accepted: 10/22/2016] [Indexed: 06/06/2023]
Abstract
Coal is an integral part of global energy production; however, coal mining is associated with numerous environmental health impacts. It is well documented that coal-mine waste can contaminate the environment with naturally-occurring radionuclides from the uranium-238 (238U) decay series. However, the behavior of the final radionuclide in the 238U-series, i.e., polonium-210 (210Po) arising from coal-mine waste-water discharge is largely unexplored. Here, results of a year-long (2014-2015) field study, in which the concentrations of 210Po in sediments and surface water of a lake that receives coal-mine waste-water discharge in West Virginia are presented. Initial measurements identified levels of 210Po in the lake sediments that were in excess of that which could be attributed to ambient U-series parent radionuclides; and were indicative of discharge site contamination of the lake ecosystem. However, control sediment obtained from a similar lake system in Iowa (an area with no coal mining or unconventional drilling) suggests that the levels of 210Po in the lake are a natural phenomenon; and are likely unrelated to waste-water treatment discharges. Elevated levels of 210Po have been reported in lake bottom sediments previously, yet very little information is available on the radioecological implications of 210Po accumulation in lake bottom sediments. The findings of this study suggest that (Monthly Energy Review, 2016) the natural accumulation and retention of 210Po in lake sediments may be a greater than previously considered (Chadwick et al., 2013) careful selection of control sites is important to prevent the inappropriate attribution of elevated levels of NORM in lake bottom ecosystems to industrial sources; and (Van Hook, 1979) further investigation of the source-terms and potential impacts on elevated 210Po in lake-sediment ecosystems is warranted.
Collapse
Affiliation(s)
- A W Nelson
- Department of Chemistry, University of Iowa, Chemistry Building, 251 North Capitol Street, Iowa City, IA 52242, United States.
| | - E S Eitrheim
- Department of Chemistry, University of Iowa, Chemistry Building, 251 North Capitol Street, Iowa City, IA 52242, United States.
| | - A W Knight
- Department of Chemistry, University of Iowa, Chemistry Building, 251 North Capitol Street, Iowa City, IA 52242, United States.
| | - D May
- Interdisciplinary Human Toxicology Program, University of Iowa, Iowa City, IA 52242, United States; University of Iowa State Hygienic Laboratory, Research Park, State Hygienic Laboratory 2490, Crosspark Road, Coralville, IA 52242, United States.
| | - M D Wichman
- Department of Environmental and Occupational Health, College of Public Health, University of Iowa, 145 N. Riverside Drive, 100 CPHB, Iowa City, IA 52242, United States.
| | - T Z Forbes
- Department of Chemistry, University of Iowa, Chemistry Building, 251 North Capitol Street, Iowa City, IA 52242, United States.
| | - M K Schultz
- Department of Chemistry, University of Iowa, Chemistry Building, 251 North Capitol Street, Iowa City, IA 52242, United States; Interdisciplinary Human Toxicology Program, University of Iowa, Iowa City, IA 52242, United States; University of Iowa State Hygienic Laboratory, Research Park, State Hygienic Laboratory 2490, Crosspark Road, Coralville, IA 52242, United States; Departments of Radiology and Radiation Oncology, Free Radical and Radiation Biology Program, University of Iowa, ML B180 FRRB, 500 Newton Road, Iowa City, IA 52242, United States.
| |
Collapse
|
31
|
Schibler J, Tomanek-Chalkley AM, Reedy JL, Zhan F, Spitz DR, Schultz MK, Goel A. Mitochondrial-Targeted Decyl-Triphenylphosphonium Enhances 2-Deoxy-D-Glucose Mediated Oxidative Stress and Clonogenic Killing of Multiple Myeloma Cells. PLoS One 2016; 11:e0167323. [PMID: 27902770 PMCID: PMC5130279 DOI: 10.1371/journal.pone.0167323] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Accepted: 11/11/2016] [Indexed: 12/16/2022] Open
Abstract
Therapeutic advances have markedly prolonged overall survival in multiple myeloma (MM) but the disease currently remains incurable. In a panel of MM cell lines (MM.1S, OPM-2, H929, and U266), using CD138 immunophenotyping, side population staining, and stem cell-related gene expression, we demonstrate the presence of stem-like tumor cells. Hypoxic culture conditions further increased CD138low stem-like cells with upregulated expression of OCT4 and NANOG. Compared to MM cells, these stem-like cells maintained lower steady-state pro-oxidant levels with increased uptake of the fluorescent deoxyglucose analog. In primary human MM samples, increased glycolytic gene expression correlated with poorer overall and event-free survival outcomes. Notably, stem-like cells showed increased mitochondrial mass, rhodamine 123 accumulation, and orthodox mitochondrial configuration while more condensed mitochondria were noted in the CD138high cells. Glycolytic inhibitor 2-deoxyglucose (2-DG) induced ER stress as detected by qPCR (BiP, ATF4) and immunoblotting (BiP, CHOP) and increased dihydroethidium probe oxidation both CD138low and CD138high cells. Treatment with a mitochondrial-targeting agent decyl-triphenylphosphonium (10-TPP) increased intracellular steady-state pro-oxidant levels in stem-like and mature MM cells. Furthermore, 10-TPP mediated increases in mitochondrial oxidant production were suppressed by ectopic expression of manganese superoxide dismutase. Relative to 2-DG or 10-TPP alone, 2-DG plus 10-TPP combination showed increased caspase 3 activation in MM cells with minimal toxicity to the normal hematopoietic progenitor cells. Notably, treatment with polyethylene glycol conjugated catalase significantly reduced 2-DG and/or 10-TPP-induced apoptosis of MM cells. Also, the combination of 2-DG with 10-TPP decreased clonogenic survival of MM cells. Taken together, this study provides a novel strategy of metabolic oxidative stress-induced cytotoxicity of MM cells via 2-DG and 10-TPP combination therapy.
Collapse
Affiliation(s)
- Jeanine Schibler
- Interdisciplinary Graduate Program in Molecular and Cellular Biology, University of Iowa, Iowa City, IA, United States of America
| | - Ann M. Tomanek-Chalkley
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa, Iowa City, IA, United States of America
| | - Jessica L. Reedy
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa, Iowa City, IA, United States of America
| | - Fenghuang Zhan
- Interdisciplinary Graduate Program in Molecular and Cellular Biology, University of Iowa, Iowa City, IA, United States of America
- Department of Internal Medicine, University of Iowa, Iowa City, IA, United States of America
| | - Douglas R. Spitz
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa, Iowa City, IA, United States of America
| | - Michael K. Schultz
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa, Iowa City, IA, United States of America
- Department of Radiology, University of Iowa, Iowa City, IA, United States of America
| | - Apollina Goel
- Interdisciplinary Graduate Program in Molecular and Cellular Biology, University of Iowa, Iowa City, IA, United States of America
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa, Iowa City, IA, United States of America
- * E-mail:
| |
Collapse
|
32
|
Reedy JL, Hedlund DK, Gabr MT, Henning GM, Pigge FC, Schultz MK. Synthesis and Evaluation of Tetraarylethylene-based Mono-, Bis-, and Tris(pyridinium) Derivatives for Image-Guided Mitochondria-Specific Targeting and Cytotoxicity of Metastatic Melanoma Cells. Bioconjug Chem 2016; 27:2424-2430. [PMID: 27643916 DOI: 10.1021/acs.bioconjchem.6b00394] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Metastatic melanoma is the most aggressive and lethal form of skin cancer. Emerging evidence suggests that differences in melanoma metabolism relative to nonmalignant cells represent potential targets for improved therapy for melanoma. Specifically, melanoma cells exhibit increased mitochondrial electron transport chain (ETC) activity and concomitant hyperpolarized mitochondrial membrane potential relative to nonmalignant cells. We have synthesized several new fluorescent lipophilic vinylpyridinium cations built from tetraarylethylene scaffolds that target mitochondria via attraction to the hyperpolarized mitochondrial membrane potential. Mitochondria-specific accumulation in melanoma cells relative to normal human fibroblasts was demonstrated using confocal fluorescence microscopy and resulted in the disruption of oxidative metabolism leading to melanoma specific cell death in vitro. Thus, the pyridinium tetraarylethylene platform represents a promising new mitochondrial-targeted delivery vehicle with potential imaging and therapeutic properties.
Collapse
Affiliation(s)
- Jessica L Reedy
- Departments of Radiology and Radiation Oncology, Free Radical and Radiation Biology Program and ‡Department of Chemistry, The University of Iowa , Iowa City, Iowa 52242, United States
| | - Devin K Hedlund
- Departments of Radiology and Radiation Oncology, Free Radical and Radiation Biology Program and ‡Department of Chemistry, The University of Iowa , Iowa City, Iowa 52242, United States
| | - Moustafa T Gabr
- Departments of Radiology and Radiation Oncology, Free Radical and Radiation Biology Program and ‡Department of Chemistry, The University of Iowa , Iowa City, Iowa 52242, United States
| | - Grant M Henning
- Departments of Radiology and Radiation Oncology, Free Radical and Radiation Biology Program and ‡Department of Chemistry, The University of Iowa , Iowa City, Iowa 52242, United States
| | - F Christopher Pigge
- Departments of Radiology and Radiation Oncology, Free Radical and Radiation Biology Program and ‡Department of Chemistry, The University of Iowa , Iowa City, Iowa 52242, United States
| | - Michael K Schultz
- Departments of Radiology and Radiation Oncology, Free Radical and Radiation Biology Program and ‡Department of Chemistry, The University of Iowa , Iowa City, Iowa 52242, United States
| |
Collapse
|
33
|
Knight AW, Eitrheim ES, Nelson AW, Peterson M, McAlister D, Forbes TZ, Schultz MK. Trace-Level Extraction Behavior of Actinide Elements by Aliphatic Alcohol Extractants in Mineral Acids: Insights into the Trace Solution Chemistry of Protactinium. Solvent Extraction and Ion Exchange 2016. [DOI: 10.1080/07366299.2016.1207460] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
34
|
Nelson AW, Johns AJ, Eitrheim ES, Knight AW, Basile M, Bettis EA, Schultz MK, Forbes TZ. Partitioning of naturally-occurring radionuclides (NORM) in Marcellus Shale produced fluids influenced by chemical matrix. Environ Sci Process Impacts 2016; 18:456-463. [PMID: 26952871 PMCID: PMC5538885 DOI: 10.1039/c5em00540j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Naturally-occurring radioactive materials (NORM) associated with unconventional drilling produced fluids from the Marcellus Shale have raised environmental concerns. However, few investigations into the fundamental chemistry of NORM in Marcellus Shale produced fluids have been performed. Thus, we performed radiochemical experiments with Marcellus Shale produced fluids to understand the partitioning behavior of major radioelements of environmental health concern (uranium (U), thorium (Th), radium (Ra), lead (Pb), and polonium (Po)). We applied a novel radiotracer, (203)Pb, to understand the behavior of trace-levels of (210)Pb in these fluids. Ultrafiltration experiments indicated U, Th, and Po are particle reactive in Marcellus Shale produced fluids and Ra and Pb are soluble. Sediment partitioning experiments revealed that >99% of Ra does not adsorb to sediments in the presence of Marcellus Shale produced fluids. Further experiments indicated that although Ra adsorption is related to ionic strength, the concentrations of heavier alkaline earth metals (Ba, Sr) are stronger predictors of Ra solubility.
Collapse
Affiliation(s)
- Andrew W Nelson
- Interdisciplinary Human Toxicology Program, University of Iowa, ML B180 FRRB, 500 Newton Road, Iowa City, Iowa, USA 52242.
| | | | | | | | | | | | | | | |
Collapse
|
35
|
Bondareva L, Schultz MK. Investigation of the tritium content in surface water, bottom sediments (zoobenthos), macrophytes, and fish in the mid-stream region of the Yenisei River (Siberia, Russia). Environ Sci Pollut Res Int 2015; 22:18127-18136. [PMID: 26178837 DOI: 10.1007/s11356-015-5042-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2015] [Accepted: 07/05/2015] [Indexed: 06/04/2023]
Abstract
The potential sources of tritium input to the Yenisei River ecosystem are derived from local operations of nuclear facilities of the Mining and Chemical Combine operated by the state-owned Rosatom corporation and from sources derived from global weapons testing fallout and nuclear power. The background tritium concentrations in zoobenthos, bottom sediments, relevant commercial fish species, and widespread endogenous aquatic plants have been obtained for the first time in this region. Our results demonstrate that the major input term of tritium to this region of the Yenisei is derived from nearby mining operations of Rosatom, with tritium concentrations in aquatic plants marginally exceeding the observed background values obtained from upstream control sample collection sites.
Collapse
Affiliation(s)
| | - Michael K Schultz
- Department of Radiology, Free Radical and Radiation Biology Program, The University of Iowa, Iowa City, IA, USA
| |
Collapse
|
36
|
Tworowska I, Ranganathan D, Thamake S, Delpassand E, Mojtahedi A, Schultz MK, Zhernosekov K, Marx S. Radiosynthesis of clinical doses of ⁶⁸Ga-DOTATATE (GalioMedix™) and validation of organic-matrix-based ⁶⁸Ge/⁶⁸Ga generators. Nucl Med Biol 2015; 43:19-26. [PMID: 26702783 DOI: 10.1016/j.nucmedbio.2015.08.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2014] [Revised: 08/03/2015] [Accepted: 08/25/2015] [Indexed: 11/29/2022]
Abstract
INTRODUCTION 68Ga-DOTATATE is a radiolabeled peptide-based agonist that targets somatostatin receptors overexpressed in neuroendocrine tumors. Here, we present our results on validation of organic matrix 68Ge/68Ga generators (ITG GmbH) applied for radiosynthesis of the clinical doses of 68Ga-DOTATATE (GalioMedixTM). METHODS The clinical grade of DOTATATE (25 μg±5 μg) compounded in 1 M NaOAc at pH=5.5 was labeled manually with 514±218 MBq (13.89±5.9 mCi) of 68Ga eluate in 0.05 N HCl at 95°C for 10 min. The radiochemical purity of the final dose was validated using radio-TLC. The quality control of clinical doses included tests of their osmolarity, endotoxin level, radionuclide identity, filter integrity, pH, sterility and 68Ge breakthrough. RESULTS The final dose of 272±126 MBq (7.35±3.4 mCi) of 68Ga-DOTATATE was produced with a radiochemical yield (RCY) of 99%±1%. The total time required for completion of radiolabeling and quality control averaged approximately 35 min. This resulted in delivery of 50%±7% of 68Ga-DOTATATE at the time of calibration (not decay corrected). CONCLUSIONS 68Ga eluted from the generator was directly applied for labeling of DOTA-peptide with no additional pre-concentration or pre-purification of isotope. The low acidity of 68Ga eluate allows for facile synthesis of clinical doses with radiochemical and radionuclide purity higher than 98% and average activity of 272±126 MBq (7.3±3 mCi). There is no need for post-labeling C18 Sep-Pak purification of final doses of radiotracer. Advances in knowledge and implications for patient care. The clinical interest in validation of 68Galabeled agents has increased in the past years due to availability of generators from different vendors (Eckert-Ziegler, ITG, iThemba), favorable approach of U.S. FDA agency to initiate clinical trials, and collaboration of U.S. centers with leading EU clinical sites. The list of 68Ga-labeled tracers evaluated in clinical studies should growth because of the sensitivity of PET technique, the simplicity of the shakebake approach for the dose preparation and reliability of 68Ge/68Ga generators. Our studies have confirmed the reproducible elution profile, and high reliability of ITG GmbH generators required for routine doses preparation according to FDA recommendations.
Collapse
Affiliation(s)
| | | | | | | | | | - Michael K Schultz
- Department of Radiology, University of Iowa, Iowa City, IA USA; Department of Radiation Oncology, University of Iowa, Iowa City, IA USA
| | | | | |
Collapse
|
37
|
Nelson AW, Eitrheim ES, Knight AW, May D, Mehrhoff MA, Shannon R, Litman R, Burnett WC, Forbes TZ, Schultz MK. Understanding the Radioactive Ingrowth and Decay of Naturally Occurring Radioactive Materials in the Environment: An Analysis of Produced Fluids from the Marcellus Shale. Environ Health Perspect 2015; 123:689-96. [PMID: 25831257 PMCID: PMC4492269 DOI: 10.1289/ehp.1408855] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2014] [Accepted: 03/11/2015] [Indexed: 05/26/2023]
Abstract
BACKGROUND The economic value of unconventional natural gas resources has stimulated rapid globalization of horizontal drilling and hydraulic fracturing. However, natural radioactivity found in the large volumes of "produced fluids" generated by these technologies is emerging as an international environmental health concern. Current assessments of the radioactivity concentration in liquid wastes focus on a single element-radium. However, the use of radium alone to predict radioactivity concentrations can greatly underestimate total levels. OBJECTIVE We investigated the contribution to radioactivity concentrations from naturally occurring radioactive materials (NORM), including uranium, thorium, actinium, radium, lead, bismuth, and polonium isotopes, to the total radioactivity of hydraulic fracturing wastes. METHODS For this study we used established methods and developed new methods designed to quantitate NORM of public health concern that may be enriched in complex brines from hydraulic fracturing wastes. Specifically, we examined the use of high-purity germanium gamma spectrometry and isotope dilution alpha spectrometry to quantitate NORM. RESULTS We observed that radium decay products were initially absent from produced fluids due to differences in solubility. However, in systems closed to the release of gaseous radon, our model predicted that decay products will begin to ingrow immediately and (under these closed-system conditions) can contribute to an increase in the total radioactivity for more than 100 years. CONCLUSIONS Accurate predictions of radioactivity concentrations are critical for estimating doses to potentially exposed individuals and the surrounding environment. These predictions must include an understanding of the geochemistry, decay properties, and ingrowth kinetics of radium and its decay product radionuclides.
Collapse
Affiliation(s)
- Andrew W Nelson
- Interdisciplinary Human Toxicology Program, University of Iowa, Iowa City, Iowa, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
38
|
Knight AW, Nelson AW, Eitrheim ES, Forbes TZ, Schultz MK. A chromatographic separation of neptunium and protactinium using 1-octanol impregnated onto a solid phase support. J Radioanal Nucl Chem 2015. [DOI: 10.1007/s10967-015-4124-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
39
|
Nelson AW, Knight AW, Eitrheim ES, Schultz MK. Monitoring radionuclides in subsurface drinking water sources near unconventional drilling operations: a pilot study. J Environ Radioact 2015; 142:24-28. [PMID: 25622134 PMCID: PMC6295908 DOI: 10.1016/j.jenvrad.2015.01.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2014] [Revised: 10/01/2014] [Accepted: 01/06/2015] [Indexed: 05/30/2023]
Abstract
Unconventional drilling (the combination of hydraulic fracturing and horizontal drilling) to extract oil and natural gas is expanding rapidly around the world. The rate of expansion challenges scientists and regulators to assess the risks of the new technologies on drinking water resources. One concern is the potential for subsurface drinking water resource contamination by naturally occurring radioactive materials co-extracted during unconventional drilling activities. Given the rate of expansion, opportunities to test drinking water resources in the pre- and post-fracturing setting are rare. This pilot study investigated the levels of natural uranium, lead-210, and polonium-210 in private drinking wells within 2000 m of a large-volume hydraulic fracturing operation--before and approximately one-year following the fracturing activities. Observed radionuclide concentrations in well waters tested did not exceed maximum contaminant levels recommended by state and federal agencies. No statistically-significant differences in radionuclide concentrations were observed in well-water samples collected before and after the hydraulic fracturing activities. Expanded monitoring of private drinking wells before and after hydraulic fracturing activities is needed to develop understanding of the potential for drinking water resource contamination from unconventional drilling and gas extraction activities.
Collapse
Affiliation(s)
- Andrew W Nelson
- Interdisciplinary Human Toxicology Program, University of Iowa, Iowa City, IA 52242, USA.
| | - Andrew W Knight
- Department of Chemistry, University of Iowa, Iowa City, IA 52242, USA.
| | - Eric S Eitrheim
- Department of Chemistry, University of Iowa, Iowa City, IA 52242, USA.
| | - Michael K Schultz
- Interdisciplinary Human Toxicology Program, University of Iowa, Iowa City, IA 52242, USA; Departments of Radiology and Radiation Oncology, Free Radical and Radiation Biology Program, Medical Scientist Training Program, University of Iowa, Iowa City, IA 52242, USA.
| |
Collapse
|
40
|
Knight AW, Eitrheim ES, Nelson AW, Nelson S, Schultz MK. A simple-rapid method to separate uranium, thorium, and protactinium for U-series age-dating of materials. J Environ Radioact 2014; 134:66-74. [PMID: 24681438 PMCID: PMC5538884 DOI: 10.1016/j.jenvrad.2014.02.010] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2013] [Revised: 02/05/2014] [Accepted: 02/18/2014] [Indexed: 05/06/2023]
Abstract
Uranium-series dating techniques require the isolation of radionuclides in high yields and in fractions free of impurities. Within this context, we describe a novel-rapid method for the separation and purification of U, Th, and Pa. The method takes advantage of differences in the chemistry of U, Th, and Pa, utilizing a commercially-available extraction chromatographic resin (TEVA) and standard reagents. The elution behavior of U, Th, and Pa were optimized using liquid scintillation counting techniques and fractional purity was evaluated by alpha-spectrometry. The overall method was further assessed by isotope dilution alpha-spectrometry for the preliminary age determination of an ancient carbonate sample obtained from the Lake Bonneville site in western Utah (United States). Preliminary evaluations of the method produced elemental purity of greater than 99.99% and radiochemical recoveries exceeding 90% for U and Th and 85% for Pa. Excellent purity and yields (76% for U, 96% for Th and 55% for Pa) were also obtained for the analysis of the carbonate samples and the preliminary Pa and Th ages of about 39,000 years before present are consistent with (14)C-derived age of the material.
Collapse
Affiliation(s)
- Andrew W Knight
- Department of Chemistry, E373 CB, The University of Iowa, Iowa City, IA 52246, USA.
| | - Eric S Eitrheim
- Department of Chemistry, E373 CB, The University of Iowa, Iowa City, IA 52246, USA.
| | - Andrew W Nelson
- Interdeciplinary Human Toxicology Program, E373 CB, The University of Iowa, IA 52246, USA.
| | - Steven Nelson
- Department of Geological Sciences, Brigham Young University, S389 ESC, Provo, UT 84602, USA.
| | - Michael K Schultz
- Departments of Radiology and Radiation Oncology, Free Radical and Radiation Biology Program, Interdisciplinary Human Toxicology Program, The University of Iowa, ML B180 FRRB, 500 Newton Road, Iowa City, IA 52246, USA.
| |
Collapse
|
41
|
Kim Y, Seol DR, Mohapatra S, Sunderland JJ, Schultz MK, Domann FE, Lim TH. Locally targeted delivery of a micron-size radiation therapy source using temperature-sensitive hydrogel. Int J Radiat Oncol Biol Phys 2014; 88:1142-7. [PMID: 24495593 DOI: 10.1016/j.ijrobp.2013.12.025] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2013] [Revised: 12/12/2013] [Accepted: 12/14/2013] [Indexed: 11/16/2022]
Abstract
PURPOSE To propose a novel radiation therapy (RT) delivery modality: locally targeted delivery of micron-size RT sources by using temperature-sensitive hydrogel (RT-GEL) as an injectable vehicle. METHODS AND MATERIALS Hydrogel is a water-like liquid at room temperature but gels at body temperature. Two US Food and Drug Administration-approved polymers were synthesized. Indium-111 (In-111) was used as the radioactive RT-GEL source. The release characteristics of In-111 from polymerized RT-GEL were evaluated. The injectability and efficacy of RT-GEL delivery to human breast tumor were tested using animal models with control datasets of RT-saline injection. As proof-of-concept studies, a total of 6 nude mice were tested by injecting 4 million tumor cells into their upper backs after a week of acclimatization. Three mice were injected with RT-GEL and 3 with RT-saline. Single-photon emission computed tomography (SPECT) and CT scans were performed on each mouse at 0, 24, and 48 h after injection. The efficacy of RT-GEL was determined by comparison with that of the control datasets by measuring kidney In-111 accumulation (mean nCi/cc), representing the distant diffusion of In-111. RESULTS RT-GEL was successfully injected into the tumor by using a 30-gauge needle. No difficulties due to polymerization of hydrogel during injection and intratumoral pressure were observed during RT-GEL injection. No back flow occurred for either RT-GEL or RT-saline. The residual tumor activities of In-111 were 49% at 24 h (44% at 48 h, respectively) for RT-GEL and 29% (22%, respectively) for RT-saline. Fused SPECT-CT images of RT-saline showed considerable kidney accumulation of In-111 (2886%, 261%, and 262% of RT-GEL at 0, 24, and 48 h, respectively). CONCLUSIONS RT-GEL was successfully injected and showed much higher residual tumor activity: 170% (200%, respectively), than that of RT-saline at 24 h (48 h, respectively) after injection with a minimal accumulation of In-111 to the kidneys. Preliminary data of RT-GEL as a delivery modality of a radiation source to a local tumor are promising.
Collapse
Affiliation(s)
- Yusung Kim
- Department of Radiation Oncology, The University of Iowa, Iowa City, Iowa.
| | - Dong Rim Seol
- Department of Orthopaedic Surgery, The University of Iowa, Iowa City, Iowa
| | - Sucheta Mohapatra
- Department of Biomedical Engineering, The University of Iowa, Iowa City, Iowa
| | | | - Michael K Schultz
- Department of Radiation Oncology, The University of Iowa, Iowa City, Iowa; Department of Radiology, The University of Iowa, Iowa City, Iowa
| | - Frederick E Domann
- Department of Radiation Oncology, The University of Iowa, Iowa City, Iowa; Department of Surgery, The University of Iowa, Iowa City, Iowa
| | - Tae-Hong Lim
- Department of Biomedical Engineering, The University of Iowa, Iowa City, Iowa
| |
Collapse
|
42
|
Mueller D, Klette I, Baum RP, Gottschaldt M, Schultz MK, Breeman WAP. Correction to Simplified NaCl Based 68Ga Concentration and Labeling Procedure for Rapid Synthesis of 68Ga Radiopharmaceuticals in High Radiochemical Purity. Bioconjug Chem 2013. [DOI: 10.1021/bc400437p] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
43
|
Schultz MK. Theranostics, Gallium-68, and Other Radionuclides: A Pathway to Personalized Diagnosis and Treatment. J Nucl Med 2013. [DOI: 10.2967/jnumed.113.121350] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
|
44
|
Martin ME, O'Dorisio MS, Leverich WM, Kloepping KC, Schultz MK, Schultz MK. "Click"-cyclized (68)Ga-labeled peptides for molecular imaging and therapy: synthesis and preliminary in vitro and in vivo evaluation in a melanoma model system. Recent Results Cancer Res 2013; 194:149-75. [PMID: 22918759 PMCID: PMC3799893 DOI: 10.1007/978-3-642-27994-2_9] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Cyclization techniques are used often to impart higher in vivo stability and binding affinity to peptide targeting vectors for molecular imaging and therapy. The two most often used techniques to impart these qualities are lactam bridge construction and disulfide bond formation. While these techniques have been demonstrated to be effective, orthogonal protection/deprotection steps can limit achievable product yields. In the work described in this chapter, new α-melanocyte stimulating hormone (α-MSH) peptide analogs were synthesized and cyclized by copper-catalyzed terminal azide-alkyne cycloaddition "click" chemistry techniques. The α-MSH peptide and its cognate receptor (melanocortin receptor subtype 1, MC1R) represent a well-characterized model system to examine the effect of the triazole linkage for peptide cyclization on receptor binding in vitro and in vivo. Four new DOTA-conjugated α-MSH analogs were cyclized and evaluated by in vitro competitive binding assays, serum stability testing, and in vivo imaging by positron emission tomography (PET) of tumor-bearing mice. These new DOTA-conjugated click-cyclized analogs exhibited selective high binding affinity (<2 nM) for MC1R on melanoma cells in vitro, high stability in human serum, and produced high-contrast PET/CT images of tumor xenografts. (68)Ga-labeled DOTA bioconjugates displayed rapid pharmacokinetics with receptor-mediated tumor accumulation of up to 16 ± 5% ID/g. The results indicate that the triazole ring is an effective bioisosteric replacement for the standard lactam bridge assemblage for peptide cyclization. Radiolabeling results confirm that Cu catalyst is sufficiently removed prior to DOTA chelator addition to enable insertion of radio metals or stable metals for molecular imaging and therapy. Thus, these click-chemistry-cyclized variants show promise as agents for melanocortin receptor-targeted imaging and radionuclide therapy.
Collapse
Affiliation(s)
- Molly E. Martin
- Department of Pediatric Hematology/Oncology, Carver College of Medicine, The University of Iowa
| | - M. Sue O'Dorisio
- Department of Pediatric Hematology/Oncology, Carver College of Medicine, The University of Iowa,Corresponding Author: Michael K. Schultz PhD, Departments of Radiology and Radiation Oncology (Free Radical Radiation Biology Program), Carver College of Medicine, The University of Iowa, ML B180, 500 Newton Road, Iowa City, IA 52242. Tel: +1 (319) 356-3380; Fax: +1 (319) 335-8668;
| | - Whitney M. Leverich
- Department of Pediatric Hematology/Oncology, Carver College of Medicine, The University of Iowa
| | - Kyle C. Kloepping
- Department of Radiology, Carver College of Medicine, The University of Iowa,Department of Radiation Oncology (Free Radical Radiation Biology Program), Carver College of Medicine, The University of Iowa
| | - Michael K. Schultz
- Department of Radiology, Carver College of Medicine, The University of Iowa,Department of Radiation Oncology (Free Radical Radiation Biology Program), Carver College of Medicine, The University of Iowa,Corresponding Author: Michael K. Schultz PhD, Departments of Radiology and Radiation Oncology (Free Radical Radiation Biology Program), Carver College of Medicine, The University of Iowa, ML B180, 500 Newton Road, Iowa City, IA 52242. Tel: +1 (319) 356-3380; Fax: +1 (319) 335-8668;
| | | |
Collapse
|
45
|
Schultz MK, Donahue P, Musgrave NI, Zhernosekov K, Naidoo C, Razbash A, Tworovska I, Dick DW, Watkins GL, Graham MM, Runde W, Clanton JA, Sunderland JJ. An Increasing Role for 68Ga PET Imaging: A Perspective on the Availability of Parent 68Ge Material for Generator Manufacturing in an Expanding Market. ACTA ACUST UNITED AC 2013. [DOI: 10.5005/jp-journals-10028-1053] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
ABSTRACT
The use of gallium-68 for molecular imaging is gaining momentum world-wide. While our understanding of 68Ga chemistry, generators, and associated synthesis modules appear to have advanced to a clinically-reliable stage, uncertainty in the supply of radiopharmaceutically-suitable parent is of significant concern. In this work, we examine the current supply of 68Ge in an effort to better understand the potential for expansion of manufacturing to meet an increasing demand for 68Ga. Although specific information on sales and demand of 68Ge is highly business sensitive and thus guarded, our examination finds no shortage in the current supply of 68Ge. On the other hand, increases in the use of 68Ge generators for clinical applications in the United States point to the need for continued support for production at DOE laboratories in the United States to ensure a reliable supply and suggests that new commercial facilities may be needed to meet the increasing demand.
How to cite this article
Schultz MK, Donahue P, Musgrave NI, Zhernosekov K, Naidoo C, Razbash A, Tworovska I, Dick DW, Watkins GL, Graham MM, Runde W, Clanton JA, Sunderland JJ. An Increasing Role for 68Ga PET Imaging: A Perspective on the Availability of Parent 68Ge Material for Generator Manufacturing in an Expanding Market. J Postgrad Med Edu Res 2013;47(1):26-30.
Collapse
|
46
|
Schultz MK, Mueller D, Baum RP, Leonard Watkins G, Breeman WAP. A new automated NaCl based robust method for routine production of gallium-68 labeled peptides. Appl Radiat Isot 2012; 76:46-54. [PMID: 23026223 DOI: 10.1016/j.apradiso.2012.08.011] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2012] [Accepted: 08/13/2012] [Indexed: 11/29/2022]
Abstract
A new NaCl based method for preparation of gallium-68 labeled radiopharmaceuticals has been adapted for use with an automated gallium-68 generator system. The method was evaluated based on 56 preparations of [(68)Ga]DOTATOC and compared to a similar acetone-based approach. Advantages of the new NaCl approach include reduced preparation time (<15 min) and removal of organic solvents. The method produces high peptide-bound % (>97%), and specific activity (>40 MBq nmole(-1) [(68)Ga]DOTATOC) and is well-suited for clinical production of radiopharmaceuticals.
Collapse
Affiliation(s)
- Michael K Schultz
- Department of Radiology, The University of Iowa, 200 Hawkins Drive, Iowa City, IA 52242, USA
| | | | | | | | | |
Collapse
|
47
|
Mueller D, Klette I, Baum RP, Gottschaldt M, Schultz MK, Breeman WAP. Simplified NaCl based (68)Ga concentration and labeling procedure for rapid synthesis of (68)Ga radiopharmaceuticals in high radiochemical purity. Bioconjug Chem 2012; 23:1712-7. [PMID: 22755505 DOI: 10.1021/bc300103t] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A simple sodium chloride (NaCl) based (68)Ga eluate concentration and labeling method that enables rapid, high-efficiency labeling of DOTA conjugated peptides in high radiochemical purity is described. The method utilizes relatively few reagents and comprises minimal procedural steps. It is particularly well-suited for routine automated synthesis of clinical radiopharmaceuticals. For the (68)Ga generator eluate concentration step, commercially available cation-exchange cartridges and (68)Ga generators were used. The (68)Ga generator eluate was collected by use of a strong cation exchange cartridge. 98% of the total activity of (68)Ga was then eluted from the cation exchange cartridge with 0.5 mL of 5 M NaCl solution containing a small amount of 5.5 M HCl. After buffering with ammonium acetate, the eluate was used directly for radiolabeling of DOTATOC and DOTATATE. The (68)Ga-labeled peptides were obtained in higher radiochemical purity compared to other commonly used procedures, with radiochemical yields greater than 80%. The presence of (68)Ge could not be detected in the final product. The new method obviates the need for organic solvents, which eliminates the required quality control of the final product by gas chromatography, thereby reducing postsynthesis analytical effort significantly. The (68)Ga-labeled products were used directly, with no subsequent purification steps, such as solid-phase extraction. The NaCl method was further evaluated using an automated fluid handling system and it routinely facilitates radiochemical yields in excess of 65% in less than 15 min, with radiochemical purity consistently greater than 99% for the preparation of (68)Ga-DOTATOC.
Collapse
Affiliation(s)
- Dirk Mueller
- Zentralklinik Bad Berka, Department of Nuclear Medicine/PET Center, 99437 Bad Berka, Germany.
| | | | | | | | | | | |
Collapse
|
48
|
Schultz MK. Second world congress on 68Ga molecular imaging. J Nucl Med 2012; 53:14N. [PMID: 22753426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023] Open
|
49
|
Schultz MK, Wright LKM, Stone MF, Schwartz JE, Kelley NR, Moffett MC, Lee RB, Lumley LA. The anticholinergic and antiglutamatergic drug caramiphen reduces seizure duration in soman-exposed rats: synergism with the benzodiazepine diazepam. Toxicol Appl Pharmacol 2012; 259:376-86. [PMID: 22310180 DOI: 10.1016/j.taap.2012.01.017] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2011] [Revised: 01/20/2012] [Accepted: 01/22/2012] [Indexed: 11/26/2022]
Abstract
Therapy of seizure activity following exposure to the nerve agent soman (GD) includes treatment with the anticonvulsant diazepam (DZP), an allosteric modulator of γ-aminobutyric acid A (GABA(A)) receptors. However, seizure activity itself causes the endocytosis of GABA(A) receptors and diminishes the inhibitory effects of GABA, thereby reducing the efficacy of DZP. Treatment with an N-methyl-d-aspartic acid (NMDA) receptor antagonist prevents this reduction in GABAergic inhibition. We examined the efficacy of the NMDA receptor antagonist caramiphen edisylate (CED; 20mg/kg, im) and DZP (10mg/kg, sc), administered both separately and in combination, at 10, 20 or 30min following seizure onset for attenuation of the deleterious effects associated with GD exposure (1.2 LD(50); 132μg/kg, sc) in rats. Outcomes evaluated were seizure duration, neuropathology, acetylcholinesterase (AChE) activity, body weight, and temperature. We also examined the use of the reversible AChE inhibitor physostigmine (PHY; 0.2mg/kg, im) as a therapy for GD exposure. We found that the combination of CED and DZP yielded a synergistic effect, shortening seizure durations and reducing neuropathology compared to DZP alone, when treatment was delayed 20-30min after seizure onset. PHY reduced the number of animals that developed seizures, protected a fraction of AChE from GD inhibition, and attenuated post-exposure body weight and temperature loss independent of CED and/or DZP treatment. We conclude that: 1) CED and DZP treatment offers considerable protection against the effects of GD and 2) PHY is a potential therapeutic option following GD exposure, albeit with a limited window of opportunity.
Collapse
Affiliation(s)
- M K Schultz
- US Army Medical Research Institute of Chemical Defense, 3100 Ricketts Point Road, Aberdeen Proving Ground, MD 21010-5400, USA
| | | | | | | | | | | | | | | |
Collapse
|
50
|
Baumhover NJ, Martin ME, Parameswarappa SG, Kloepping KC, O'Dorisio MS, Pigge FC, Schultz MK. Improved synthesis and biological evaluation of chelator-modified α-MSH analogs prepared by copper-free click chemistry. Bioorg Med Chem Lett 2011; 21:5757-61. [PMID: 21873053 DOI: 10.1016/j.bmcl.2011.08.017] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2011] [Revised: 07/30/2011] [Accepted: 08/02/2011] [Indexed: 01/23/2023]
Abstract
Radionuclide chelators (DOTA, NOTA) functionalized with a monofluorocyclooctyne group were prepared. These materials reacted rapidly and in high yield with a fully deprotected azide-modified peptide via Cu-free click chemistry under mild reaction conditions (aqueous solution, room temperature). The resulting bioconjugates bind with high affinity and specificity to their cell-surface receptor targets in vitro and appear stable to degradation in mouse serum over 3h of incubation at 37°C.
Collapse
Affiliation(s)
- Nicholas J Baumhover
- Department of Radiology, Carver College of Medicine, The University of Iowa, 500 Newton Road, ML B180, Iowa City, IA 52242, USA
| | | | | | | | | | | | | |
Collapse
|