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Tang J, Zhang C, Castillo NC, Lalaurie CJ, Gao X, Dalby PA, Kozielski F. Crystal structures and molecular dynamics simulations of a humanised antibody fragment at acidic to basic pH. Sci Rep 2023; 13:16281. [PMID: 37770469 PMCID: PMC10539359 DOI: 10.1038/s41598-023-42698-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Accepted: 09/13/2023] [Indexed: 09/30/2023] Open
Abstract
Antibody-fragment (Fab) therapy development has the potential to be accelerated by computational modelling and simulations that predict their target binding, stability, formulation, manufacturability, and the impact of further protein engineering. Such approaches are currently predicated on starting with good crystal structures that closely represent those found under the solution conditions to be simulated. A33 Fab, is an undeveloped immunotherapeutic antibody candidate that was targeted to the human A33 antigen homogeneously expressed in 95% cases of primary and metastatic colorectal cancers. It is now used as a very well characterised testing ground for developing analytics, formulation and protein engineering strategies, and to gain a deeper understanding of mechanisms of destabilisation, representative of the wider therapeutic Fab platform. In this article, we report the structure of A33 Fab in two different crystal forms obtained at acidic and basic pH. The structures overlapped with RMSD of 1.33 Å overall, yet only 0.5 Å and 0.76 Å for the variable- and constant regions alone. While most of the differences were within experimental error, the switch linker between the variable and the constant regions showed some small differences between the two pHs. The two structures then enabled a direct evaluation of the impact of initial crystal structure selection on the outcomes of molecular dynamics simulations under different conditions, and their subsequent use for determining best fit solution structures using previously obtained small-angle x-ray scattering (SAXS) data. The differences in the two structures did not have a major impact on MD simulations regardless of the pH, other than a slight persistence of structure affecting the solvent accessibility of one of the predicted APR regions of A33 Fab. Interestingly, despite being obtained at pH 4 and pH 9, the two crystal structures were more similar to the SAXS solution structures obtained at pH 7, than to those at pH 4 or pH 9. Furthermore, the P65 crystal structure from pH 4 was also a better representation of the solution structures at any other pH, than was the P1 structure obtained at pH 9. Thus, while obtained at different pH, the two crystal structures may represent highly (P65) and lesser (P1) populated species that both exist at pH 7 in solution. These results now lay the foundation for confident MD simulations of A33 Fab that rationalise or predict behaviours in a range of conditions.
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Affiliation(s)
- Jiazhi Tang
- UCL School of Pharmacy, 29-39 Brunswick Square, London, WC1N 1AX, UK
| | - Cheng Zhang
- Department of Biochemical Engineering, UCL, Bernard Katz Building, Gower Street, London, WC1E 6BT, UK
| | - Nuria Codina Castillo
- Department of Biochemical Engineering, UCL, Bernard Katz Building, Gower Street, London, WC1E 6BT, UK
| | - Christophe J Lalaurie
- Department of Biochemical Engineering, UCL, Bernard Katz Building, Gower Street, London, WC1E 6BT, UK
| | - Xin Gao
- Division of Biosciences, Department of Structural and Molecular Biology, UCL, London, WC1E 6BT, UK
| | - Paul A Dalby
- Department of Biochemical Engineering, UCL, Bernard Katz Building, Gower Street, London, WC1E 6BT, UK.
| | - Frank Kozielski
- UCL School of Pharmacy, 29-39 Brunswick Square, London, WC1N 1AX, UK.
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Manafi-Farid R, Ataeinia B, Ranjbar S, Jamshidi Araghi Z, Moradi MM, Pirich C, Beheshti M. ImmunoPET: Antibody-Based PET Imaging in Solid Tumors. Front Med (Lausanne) 2022; 9:916693. [PMID: 35836956 PMCID: PMC9273828 DOI: 10.3389/fmed.2022.916693] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2022] [Accepted: 05/24/2022] [Indexed: 12/13/2022] Open
Abstract
Immuno-positron emission tomography (immunoPET) is a molecular imaging modality combining the high sensitivity of PET with the specific targeting ability of monoclonal antibodies. Various radioimmunotracers have been successfully developed to target a broad spectrum of molecules expressed by malignant cells or tumor microenvironments. Only a few are translated into clinical studies and barely into clinical practices. Some drawbacks include slow radioimmunotracer kinetics, high physiologic uptake in lymphoid organs, and heterogeneous activity in tumoral lesions. Measures are taken to overcome the disadvantages, and new tracers are being developed. In this review, we aim to mention the fundamental components of immunoPET imaging, explore the groundbreaking success achieved using this new technique, and review different radioimmunotracers employed in various solid tumors to elaborate on this relatively new imaging modality.
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Affiliation(s)
- Reyhaneh Manafi-Farid
- Research Center for Nuclear Medicine, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran
| | - Bahar Ataeinia
- Department of Radiology, Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, MA, United States
| | - Shaghayegh Ranjbar
- Division of Molecular Imaging and Theranostics, Department of Nuclear Medicine, University Hospital Salzburg, Paracelsus Medical University, Salzburg, Austria
| | - Zahra Jamshidi Araghi
- Rajaie Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Mohammad Mobin Moradi
- Research Center for Nuclear Medicine, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran
| | - Christian Pirich
- Division of Molecular Imaging and Theranostics, Department of Nuclear Medicine, University Hospital Salzburg, Paracelsus Medical University, Salzburg, Austria
| | - Mohsen Beheshti
- Division of Molecular Imaging and Theranostics, Department of Nuclear Medicine, University Hospital Salzburg, Paracelsus Medical University, Salzburg, Austria
- *Correspondence: Mohsen Beheshti ; orcid.org/0000-0003-3918-3812
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3
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Chandler CS, Bell MM, Chung SK, Veach DR, Fung EK, Punzalan B, Burnes Vargas D, Patel M, Xu H, Guo HF, Santich BH, Zanzonico PB, Monette S, Nash GM, Cercek A, Jungbluth A, Pandit-Taskar N, Cheung NKV, Larson SM, Cheal SM. Intraperitoneal Pretargeted Radioimmunotherapy for Colorectal Peritoneal Carcinomatosis. Mol Cancer Ther 2022; 21:125-137. [PMID: 34667111 PMCID: PMC9157533 DOI: 10.1158/1535-7163.mct-21-0353] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Revised: 06/22/2021] [Accepted: 10/15/2021] [Indexed: 11/16/2022]
Abstract
Peritoneal carcinomatosis (PC) is considered incurable, and more effective therapies are needed. Herein we test the hypothesis that GPA33-directed intracompartmental pretargeted radioimmunotherapy (PRIT) can cure colorectal peritoneal carcinomatosis. Nude mice were implanted intraperitoneally with luciferase-transduced GPA33-expressing SW1222 cells for aggressive peritoneal carcinomatosis (e.g., resected tumor mass 0.369 ± 0.246 g; n = 17 on day 29). For GPA33-PRIT, we administered intraperitoneally a high-affinity anti-GPA33/anti-DOTA bispecific antibody (BsAb), followed by clearing agent (intravenous), and lutetium-177 (Lu-177) or yttrium-86 (Y-86) radiolabeled DOTA-radiohapten (intraperitoneal) for beta/gamma-emitter therapy and PET imaging, respectively. The DOTA-radiohaptens were prepared from S-2-(4-aminobenzyl)-1,4,7, 10-tetraazacyclododecane tetraacetic acid chelate (DOTA-Bn). Efficacy and toxicity of single- versus three-cycle therapy were evaluated in mice 26-27 days post-tumor implantation. Single-cycle treatment ([177Lu]LuDOTA-Bn 111 MBq; tumor dose: 4,992 cGy) significantly prolonged median survival (MS) approximately 2-fold to 84.5 days in comparison with controls (P = 0.007). With three-cycle therapy (once weekly, total 333 MBq; tumor dose: 14,975 cGy), 6/8 (75%) survived long-term (MS > 183 days). Furthermore, for these treated long-term survivors, 1 mouse was completely disease free (microscopic "cure") at necropsy; the others showed stabilized disease, which was detectable during PET-CT using [86Y]DOTA-Bn. Treatment controls had MS ranging from 42-52.5 days (P < 0.001) and 19/20 mice succumbed to progressive intraperitoneal disease by 69 days. Multi-cycle GPA33 DOTA-PRIT significantly prolongs survival with reversible myelosuppression and no chronic marrow (929 cGy to blood) or kidney (982 cGy) radiotoxicity, with therapeutic indices of 12 for blood and 12 for kidneys. MTD was not reached.
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Affiliation(s)
| | - Meghan M Bell
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Sebastian K Chung
- Department of Surgery, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Darren R Veach
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
- Department of Radiology, Weill Cornell Medicine, New York, New York
| | - Edward K Fung
- Department of Radiology, Weill Cornell Medicine, New York, New York
| | - Blesida Punzalan
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
| | | | - Mitesh Patel
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Hong Xu
- Department of Pediatrics, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Hong-Fen Guo
- Department of Pediatrics, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Brian H Santich
- Department of Pediatrics, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Pat B Zanzonico
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Sébastien Monette
- Laboratory of Comparative Pathology, Memorial Sloan Kettering Cancer Center, Weill Cornell Medicine, and The Rockefeller University, New York, New York
| | - Garrett M Nash
- Department of Surgery, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Andrea Cercek
- Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Achim Jungbluth
- Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Neeta Pandit-Taskar
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Nai Kong V Cheung
- Department of Pediatrics, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Steven M Larson
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
- Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Sarah M Cheal
- Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, New York.
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Sanz L, Ibáñez-Pérez R, Guerrero-Ochoa P, Lacadena J, Anel A. Antibody-Based Immunotoxins for Colorectal Cancer Therapy. Biomedicines 2021; 9:1729. [PMID: 34829955 PMCID: PMC8615520 DOI: 10.3390/biomedicines9111729] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 11/17/2021] [Accepted: 11/18/2021] [Indexed: 01/21/2023] Open
Abstract
Monoclonal antibodies (mAbs) are included among the treatment options for advanced colorectal cancer (CRC). However, while these mAbs effectively target cancer cells, they may have limited clinical activity. A strategy to improve their therapeutic potential is arming them with a toxic payload. Immunotoxins (ITX) combining the cell-killing ability of a toxin with the specificity of a mAb constitute a promising strategy for CRC therapy. However, several important challenges in optimizing ITX remain, including suboptimal pharmacokinetics and especially the immunogenicity of the toxin moiety. Nonetheless, ongoing research is working to solve these limitations and expand CRC patients' therapeutic armory. In this review, we provide a comprehensive overview of targets and toxins employed in the design of ITX for CRC and highlight a wide selection of ITX tested in CRC patients as well as preclinical candidates.
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Affiliation(s)
- Laura Sanz
- Molecular Immunology Unit, Biomedical Research Institute, Hospital Universitario Puerta de Hierro, 28222 Madrid, Spain
| | - Raquel Ibáñez-Pérez
- Apoptosis, Immunity and Cancer Group, Aragón Health Research Institute (IIS-Aragón), University of Zaragoza, 50009 Zaragoza, Spain; (R.I.-P.); (P.G.-O.)
| | - Patricia Guerrero-Ochoa
- Apoptosis, Immunity and Cancer Group, Aragón Health Research Institute (IIS-Aragón), University of Zaragoza, 50009 Zaragoza, Spain; (R.I.-P.); (P.G.-O.)
| | - Javier Lacadena
- Department of Biochemistry and Molecular Biology, Faculty of Chemical Sciences, Complutense University, 28040 Madrid, Spain
| | - Alberto Anel
- Apoptosis, Immunity and Cancer Group, Aragón Health Research Institute (IIS-Aragón), University of Zaragoza, 50009 Zaragoza, Spain; (R.I.-P.); (P.G.-O.)
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5
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George KJH, Borjian S, Cross MC, Hicks JW, Schaffer P, Kovacs MS. Expanding the PET radioisotope universe utilizing solid targets on small medical cyclotrons. RSC Adv 2021; 11:31098-31123. [PMID: 35498914 PMCID: PMC9041346 DOI: 10.1039/d1ra04480j] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Accepted: 08/25/2021] [Indexed: 12/17/2022] Open
Abstract
Molecular imaging with medical radioisotopes enables the minimally-invasive monitoring of aberrant biochemical, cellular and tissue-level processes in living subjects. The approach requires the administration of radiotracers composed of radioisotopes attached to bioactive molecules, the pairing of which considers several aspects of the radioisotope in addition to the biological behavior of the targeting molecule to which it is attached. With the advent of modern cellular and biochemical techniques, there has been a virtual explosion in potential disease recognition antigens as well as targeting moieties, which has subsequently opened new applications for a host of emerging radioisotopes with well-matched properties. Additionally, the global radioisotope production landscape has changed rapidly, with reactor-based production and its long-defined, large-scale centralized manufacturing and distribution paradigm shifting to include the manufacture and distribution of many radioisotopes via a worldwide fleet of cyclotrons now in operation. Cyclotron-based radioisotope production has become more prevalent given the commercial availability of instruments, coupled with the introduction of new target hardware, process automation and target manufacturing methods. These advances enable sustained, higher-power irradiation of solid targets that allow hospital-based radiopharmacies to produce a suite of radioisotopes that drive research, clinical trials, and ultimately clinical care. Over the years, several different radioisotopes have been investigated and/or selected for radiolabeling due to favorable decay characteristics (i.e. a suitable half-life, high probability of positron decay, etc.), well-elucidated chemistry, and a feasible production framework. However, longer-lived radioisotopes have surged in popularity given recent regulatory approvals and incorporation of radiopharmaceuticals into patient management within the medical community. This review focuses on the applications, nuclear properties, and production and purification methods for some of the most frequently used/emerging positron-emitting, solid-target-produced radioisotopes that can be manufactured using small-to-medium size cyclotrons (≤24 MeV).
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Affiliation(s)
- K J H George
- Lawson Health Research Institute 268 Grosvenor Street London ON N6A 4V2 Canada
- Medical Biophysics, Western University 1151 Richmond Street N. London ON N6A 5C1 Canada
| | - S Borjian
- ARTMS 301-4475 Wayburn Drive Burnaby BC V5G 4X4 Canada
| | - M C Cross
- ARTMS 301-4475 Wayburn Drive Burnaby BC V5G 4X4 Canada
| | - J W Hicks
- Lawson Health Research Institute 268 Grosvenor Street London ON N6A 4V2 Canada
- Medical Biophysics, Western University 1151 Richmond Street N. London ON N6A 5C1 Canada
| | - P Schaffer
- Life Sciences, TRIUMF 4004 Wesbrook Mall Vancouver BC V6T 2A3 Canada
- ARTMS 301-4475 Wayburn Drive Burnaby BC V5G 4X4 Canada
- Radiology, University of British Columbia 2775 Laurel St Vancouver BC V5Z 1M9 Canada
- Chemistry, Simon Fraser University 8888 University Dr Burnaby BC V5A 1S6 Canada
| | - M S Kovacs
- Lawson Health Research Institute 268 Grosvenor Street London ON N6A 4V2 Canada
- Medical Biophysics, Western University 1151 Richmond Street N. London ON N6A 5C1 Canada
- Medical Imaging, Western University 1151 Richmond Street N. London ON N6A 5C1 Canada
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6
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Kumar K, Ghosh A. Radiochemistry, Production Processes, Labeling Methods, and ImmunoPET Imaging Pharmaceuticals of Iodine-124. Molecules 2021; 26:E414. [PMID: 33466827 PMCID: PMC7830191 DOI: 10.3390/molecules26020414] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 01/07/2021] [Accepted: 01/07/2021] [Indexed: 01/01/2023] Open
Abstract
Target-specific biomolecules, monoclonal antibodies (mAb), proteins, and protein fragments are known to have high specificity and affinity for receptors associated with tumors and other pathological conditions. However, the large biomolecules have relatively intermediate to long circulation half-lives (>day) and tumor localization times. Combining superior target specificity of mAbs and high sensitivity and resolution of the PET (Positron Emission Tomography) imaging technique has created a paradigm-shifting imaging modality, ImmunoPET. In addition to metallic PET radionuclides, 124I is an attractive radionuclide for radiolabeling of mAbs as potential immunoPET imaging pharmaceuticals due to its physical properties (decay characteristics and half-life), easy and routine production by cyclotrons, and well-established methodologies for radioiodination. The objective of this report is to provide a comprehensive review of the physical properties of iodine and iodine radionuclides, production processes of 124I, various 124I-labeling methodologies for large biomolecules, mAbs, and the development of 124I-labeled immunoPET imaging pharmaceuticals for various cancer targets in preclinical and clinical environments. A summary of several production processes, including 123Te(d,n)124I, 124Te(d,2n)124I, 121Sb(α,n)124I, 123Sb(α,3n)124I, 123Sb(3He,2n)124I, natSb(α, xn)124I, natSb(3He,n)124I reactions, a detailed overview of the 124Te(p,n)124I reaction (including target selection, preparation, processing, and recovery of 124I), and a fully automated process that can be scaled up for GMP (Good Manufacturing Practices) production of large quantities of 124I is provided. Direct, using inorganic and organic oxidizing agents and enzyme catalysis, and indirect, using prosthetic groups, 124I-labeling techniques have been discussed. Significant research has been conducted, in more than the last two decades, in the development of 124I-labeled immunoPET imaging pharmaceuticals for target-specific cancer detection. Details of preclinical and clinical evaluations of the potential 124I-labeled immunoPET imaging pharmaceuticals are described here.
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Affiliation(s)
- Krishan Kumar
- Laboratory for Translational Research in Imaging Pharmaceuticals, The Wright Center of Innovation in Biomedical Imaging, Department of Radiology, The Ohio State University, Columbus, OH 43212, USA;
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Coenen HH, Ermert J. Expanding PET-applications in life sciences with positron-emitters beyond fluorine-18. Nucl Med Biol 2021; 92:241-269. [PMID: 32900582 DOI: 10.1016/j.nucmedbio.2020.07.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Accepted: 07/09/2020] [Indexed: 12/20/2022]
Abstract
Positron-emission-tomography (PET) has become an indispensable diagnostic tool in modern nuclear medicine. Its outstanding molecular imaging features allow repetitive studies on one individual and with high sensitivity, though no interference. Rather few positron-emitters with near favourable physical properties, i.e. carbon-11 and fluorine-18, furnished most studies in the beginning, preferably if covalently bound as isotopic label of small molecules. With the advancement of PET-devices the scope of in vivo research in life sciences and especially that of medical applications expanded, and other than "standard" PET-nuclides received increasing significance, like the radiometals copper-64 and gallium-68. Especially during the last decades, positron-emitters of other chemical elements have gotten into the focus of interest, concomitant with the technical advancements in imaging and radionuclide production. With known nuclear imaging properties and main production methods of emerging positron-emitters their usefulness for medical application is promising and even proven for several ones already. Unfortunate decay properties could be corrected for, and β+-emitters, especially with a longer half-life, provided new possibilities for application where slower processes are of importance. Further on, (bio)chemical features of positron-emitters of other elements, among there many metals, not only expanded the field of classical clinical investigations, but also opened up new fields of application. Appropriately labelled peptides, proteins and nanoparticles lend itself as newer probes for PET-imaging, e.g. in theragnostic or PET/MR hybrid imaging. Furthermore, the potential of non-destructive in-vivo imaging with positron-emission-tomography directs the view on further areas of life sciences. Thus, exploiting the excellent methodology for basic research on molecular biochemical functions and processes is increasingly encouraged as well in areas outside of health, such as plant and environmental sciences.
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Affiliation(s)
- Heinz H Coenen
- Institut für Neurowissenschaften und Medizin, INM-5, Nuklearchemie, Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany.
| | - Johannes Ermert
- Institut für Neurowissenschaften und Medizin, INM-5, Nuklearchemie, Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany.
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Wei D, Tao Z, Shi Q, Wang L, Liu L, She T, Yi Q, Wen X, Liu L, Li S, Yang H, Jiang X. Selective Photokilling of Colorectal Tumors by Near-Infrared Photoimmunotherapy with a GPA33-Targeted Single-Chain Antibody Variable Fragment Conjugate. Mol Pharm 2020; 17:2508-2517. [PMID: 32396000 DOI: 10.1021/acs.molpharmaceut.0c00210] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Antibody-based near-infrared photoimmunotherapy (NIR-PIT) is an attractive strategy for cancer treatment. Tumor cells can be selectively and efficiently killed by the targeted delivery of an antibody-photoabsorber complex followed by exposure to NIR light. Glycoprotein A33 antigen (GPA33) is highly expressed in most human colorectal cancers (CRCs) and is an ideal diagnostic and therapeutic target. We previously produced a single-chain fragment of a variable antibody against GPA33 (A33scFv antibody). Here, we investigate the efficacy of NIR-PIT by combining A33scFv with the NIR photoabsorber IR700 (A33scFv-IR700). In vitro, recombinant A33scFv displayed specific binding and delivery of an NIR dye to GPA33-positive tumor cells. Furthermore, A33scFv-IR700-mediated NIR-PIT was successful in rapidly and specifically killing GPA33-positive colorectal tumor cells. NIR-PIT treatment induced the release of lactate dehydrogenase from tumor cells, followed by cell necrosis, rather than apoptosis, through the promotion of reactive oxygen species accumulation in tumor cells. In mice bearing LS174T tumor grafts, A33scFv selectively accumulated in GPA33-positive tumors. Following only a single injection of the conjugate and subsequent illumination, A33scFv-IR700-mediated NIR-PIT induced a significant increase in therapeutic response in LS174T-tumor mice compared with that in the non-NIR-PIT groups (p < 0.001). Because the GPA33 antigen is specifically expressed in CRC tumors, A33scFv-IR700 might be a promising antibody fragment-photoabsorber conjugate for NIR-PIT of CRC.
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Affiliation(s)
- Danfeng Wei
- Department of Dermatology, West China Hospital, Sichuan University, Chengdu 610041, China.,Medical Research Center, The Third People's Hospital of Chengdu, The Second Affiliated Chengdu Clinical College of Chongqing Medical University, Chengdu 610031, China.,Key Laboratory of Transplant Engineering and Immunology, Regenerative Medical Research Center, West China Hospital, Sichuan University, Chengdu 610041, China
| | - Ze Tao
- Key Laboratory of Transplant Engineering and Immunology, Regenerative Medical Research Center, West China Hospital, Sichuan University, Chengdu 610041, China
| | - Qiuxiao Shi
- Key Laboratory of Transplant Engineering and Immunology, Regenerative Medical Research Center, West China Hospital, Sichuan University, Chengdu 610041, China
| | - Lijun Wang
- Department of Ophthalmology, The Third People's Hospital of Chengdu, The Second Affiliated Chengdu Clinical College of Chongqing Medical University, Chengdu 610031, China
| | - Lei Liu
- Medical Research Center, The Third People's Hospital of Chengdu, The Second Affiliated Chengdu Clinical College of Chongqing Medical University, Chengdu 610031, China
| | - Tianshan She
- Key Laboratory of Transplant Engineering and Immunology, Regenerative Medical Research Center, West China Hospital, Sichuan University, Chengdu 610041, China
| | - Qin Yi
- Department of Dermatology, West China Hospital, Sichuan University, Chengdu 610041, China
| | - Xiang Wen
- Department of Dermatology, West China Hospital, Sichuan University, Chengdu 610041, China
| | - Lian Liu
- Department of Dermatology, West China Hospital, Sichuan University, Chengdu 610041, China
| | - Shengfu Li
- Key Laboratory of Transplant Engineering and Immunology, Regenerative Medical Research Center, West China Hospital, Sichuan University, Chengdu 610041, China
| | - Hao Yang
- Key Laboratory of Transplant Engineering and Immunology, Regenerative Medical Research Center, West China Hospital, Sichuan University, Chengdu 610041, China
| | - Xian Jiang
- Department of Dermatology, West China Hospital, Sichuan University, Chengdu 610041, China
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9
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Abstract
Immuno-positron emission tomography (immunoPET) is a paradigm-shifting molecular imaging modality combining the superior targeting specificity of monoclonal antibody (mAb) and the inherent sensitivity of PET technique. A variety of radionuclides and mAbs have been exploited to develop immunoPET probes, which has been driven by the development and optimization of radiochemistry and conjugation strategies. In addition, tumor-targeting vectors with a short circulation time (e.g., Nanobody) or with an enhanced binding affinity (e.g., bispecific antibody) are being used to design novel immunoPET probes. Accordingly, several immunoPET probes, such as 89Zr-Df-pertuzumab and 89Zr-atezolizumab, have been successfully translated for clinical use. By noninvasively and dynamically revealing the expression of heterogeneous tumor antigens, immunoPET imaging is gradually changing the theranostic landscape of several types of malignancies. ImmunoPET is the method of choice for imaging specific tumor markers, immune cells, immune checkpoints, and inflammatory processes. Furthermore, the integration of immunoPET imaging in antibody drug development is of substantial significance because it provides pivotal information regarding antibody targeting abilities and distribution profiles. Herein, we present the latest immunoPET imaging strategies and their preclinical and clinical applications. We also emphasize current conjugation strategies that can be leveraged to develop next-generation immunoPET probes. Lastly, we discuss practical considerations to tune the development and translation of immunoPET imaging strategies.
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Affiliation(s)
- Weijun Wei
- Department of Nuclear Medicine, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, China
- Departments of Radiology and Medical Physics, University of Wisconsin-Madison, 1111 Highland Avenue, Room 7137, Madison, Wisconsin 53705, United States
| | - Zachary T Rosenkrans
- Department of Pharmaceutical Sciences, University of Wisconsin-Madison, Madison, Wisconsin 53705, United States
| | - Jianjun Liu
- Department of Nuclear Medicine, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, China
| | - Gang Huang
- Department of Nuclear Medicine, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, China
- Shanghai Key Laboratory of Molecular Imaging, Shanghai University of Medicine and Health Sciences, Shanghai 201318, China
| | - Quan-Yong Luo
- Department of Nuclear Medicine, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai 200233, China
| | - Weibo Cai
- Departments of Radiology and Medical Physics, University of Wisconsin-Madison, 1111 Highland Avenue, Room 7137, Madison, Wisconsin 53705, United States
- Department of Pharmaceutical Sciences, University of Wisconsin-Madison, Madison, Wisconsin 53705, United States
- University of Wisconsin Carbone Cancer Center, Madison, Wisconsin 53705, United States
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10
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Gambhir SS, Shankar LK, Rosenthal E, Warram JM, Ghesani M, Hope TA, Jacobs PM, Jacobson GB, Wilson T, Siegel BA. Proceedings: Pathways for Successful Translation of New Imaging Agents and Modalities-Phase III Studies. J Nucl Med 2019; 60:736-744. [PMID: 30850482 DOI: 10.2967/jnumed.118.219824] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Accepted: 11/28/2018] [Indexed: 12/19/2022] Open
Affiliation(s)
- Sanjiv S Gambhir
- Departments of Radiology, Bioengineering, and Materials Science and Engineering, Molecular Imaging Program, Stanford University, Stanford, California
| | - Lalitha K Shankar
- Division of Cancer Treatment and Diagnosis, National Cancer Institute, Bethesda, Maryland
| | - Eben Rosenthal
- Department of Otolaryngology, Stanford University, Stanford, California
| | - Jason M Warram
- Department of Otolaryngology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Munir Ghesani
- Department of Radiology, New York University, New York, New York
| | - Thomas A Hope
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California
| | - Paula M Jacobs
- Division of Cancer Treatment and Diagnosis, National Cancer Institute, Bethesda, Maryland
| | - Gunilla B Jacobson
- Department of Radiology, Molecular Imaging Program, Stanford University, Stanford, California
| | - Terri Wilson
- Blue Earth Diagnostics, Inc., Burlington, Massachusetts; and
| | - Barry A Siegel
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri
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11
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Burvenich IJG, Parakh S, Parslow AC, Lee ST, Gan HK, Scott AM. Receptor Occupancy Imaging Studies in Oncology Drug Development. AAPS JOURNAL 2018. [DOI: 10.1208/s12248-018-0203-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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12
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Carrasquillo JA, O'Donoghue JA, Beylergil V, Ruan S, Pandit-Taskar N, Larson SM, Smith-Jones PM, Lyashchenko SK, Ohishi N, Ohtomo T, Abou-Alfa GK. I-124 codrituzumab imaging and biodistribution in patients with hepatocellular carcinoma. EJNMMI Res 2018; 8:20. [PMID: 29508107 PMCID: PMC5838028 DOI: 10.1186/s13550-018-0374-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Accepted: 02/22/2018] [Indexed: 01/03/2023] Open
Abstract
Background I-124 codrituzumab (aka GC33), an antibody directed at Glypican 3, was evaluated in patients with hepatocellular carcinoma (HCC). Fourteen patients with HCC underwent baseline imaging with I-124 codrituzumab (~ 185 MBq, 10 mg). Seven of these patients undergoing sorafenib/immunotherapy with 2.5 or 5 mg/kg of cold codrituzumab had repeat imaging, with co-infusion of I-124 codrituzumab, as part of their immunotherapy treatment. Three patients who progressed while on sorafenib/immunotherapy were re-imaged after a 4-week washout period to assess for the presence of antigen. Serial positron emission tomography (PET) imaging and pharmacokinetics were performed following I-124 codrituzumab. An ELISA assay was used to determine “cold” codrituzumab serum pharmacokinetics and compare it to that of I-124 codrituzumab. Correlation of imaging results was performed with IHC. Short-term safety assessment was also evaluated. Results Thirteen patients had tumor localization on baseline I-124 codrituzumab; heterogeneity in tumor uptake was noted. In three patients undergoing repeat imaging while on immunotherapy/sorafenib, evidence of decreased I-124 codrituzumab uptake was noted. All three patients who underwent imaging after progression while on immunotherapy continued to have I-124 codrituzumab tumor uptake. Pharmacokinetics of I-124 codrituzumab was similar to that of other intact IgG. No significant adverse events were observed related to the I-124 codrituzumab. Conclusions I-124 codrituzumab detected tumor localization in most patients with HCC. Pharmacokinetics was similar to that of other intact iodinated humanized IgG. No visible cross-reactivity with normal organs was observed. Electronic supplementary material The online version of this article (10.1186/s13550-018-0374-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Jorge A Carrasquillo
- Department of Radiology, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY, 10065, USA.
| | - Joseph A O'Donoghue
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY, 10065, USA
| | - Volkan Beylergil
- Department of Radiology, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY, 10065, USA
| | - Shutian Ruan
- Department of Radiology, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY, 10065, USA
| | - Neeta Pandit-Taskar
- Department of Radiology, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY, 10065, USA
| | - Steven M Larson
- Department of Radiology, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY, 10065, USA
| | - Peter M Smith-Jones
- Department of Radiology, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY, 10065, USA.,Department of Psychiatry and Behavioral Science, Stony Brook University Hospital, 101 Nicolls Road, Stony Brook, NY, 11794, USA.,Department of Radiology, Stony Brook University Hospital, 101 Nicolls Road, Stony Brook, NY, 11794, USA
| | - Serge K Lyashchenko
- Department of Radiology, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY, 10065, USA
| | - Norihisa Ohishi
- Chugai Pharmaceutical Co., Ltd., 1-1 Nihonbashi-Muromachi 2-Chome Chuo-ku, Tokyo, 103-8324, Japan
| | - Toshihiko Ohtomo
- Chugai Pharmaceutical Co., Ltd., 1-1 Nihonbashi-Muromachi 2-Chome Chuo-ku, Tokyo, 103-8324, Japan
| | - Ghassan K Abou-Alfa
- Department of Medicine, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY, 10065, USA
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13
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Wagner M, Wuest M, Hamann I, Lopez-Campistrous A, McMullen TPW, Wuest F. Molecular imaging of platelet-derived growth factor receptor-alpha (PDGFRα) in papillary thyroid cancer using immuno-PET. Nucl Med Biol 2017; 58:51-58. [PMID: 29367096 DOI: 10.1016/j.nucmedbio.2017.12.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Revised: 12/11/2017] [Accepted: 12/13/2017] [Indexed: 12/22/2022]
Abstract
INTRODUCTION Receptor tyrosine kinase (RTK) platelet-derived growth factor receptor-alpha (PDGFRα) was recently identified as a molecular switch for dedifferentiation in thyroid cancer that predicts resistance to therapy as well as recurrence of disease in papillary thyroid cancer. Here we describe the radiolabeling and functional characterization of an imaging probe based on a PDGFRα-specific monoclonal antibody (mAb) for immuno-PET imaging of PDGFRα in papillary thyroid cancer. METHODS Antibody D13C6 (Cell Signaling) was decorated with chelator NOTA using bioconjugation reaction with 2-(p-NCS-Bz)-NOTA. Radiolabeling was carried out using 40 μg of antibody-NOTA conjugate with 143-223 MBq of [64Cu]CuCl2 in 0.25 M NaOAc (pH 5.5) at 30 °C for 1 h. The reaction mixture was purified with size-exclusion chromatography (PD-10 column). PDGFRα and mock transfected B-CPAP thyroid cancer cells lines for validation of 64Cu-labeled immuno-conjugates were generated using LVX-Tet-On technology. PET imaging was performed in NSG mice bearing bilaterally-induced PDGFRα (+/-) B-CPAP tumors. RESULTS Bioconjugation of NOTA chelator to monoclonal antibody D13C6 resulted in 2.8 ± 1.3 chelator molecules per antibody as determined by radiometric titration with 64Cu. [64Cu]Cu-NOTA-D13C6 was isolated in high radiochemical purity (>98%) and good radiochemical yields (19-61%). The specific activity was 0.9-5.1 MBq/μg. Cellular uptake studies revealed a specific radiotracer uptake in PDGFRα expressing cells compared to control cells. PET imaging resulted in SUVmean values of ~5.5 for PDGFRα (+) and ~2 for PDGFRα (-) tumors, after 48 h p.i.. After 1 h, radiotracer uptake was also observed in the bone marrow (SUVmean ~5) and spleen (SUVmean ~8.5). CONCLUSION Radiolabeled antibody [64Cu]Cu-NOTA-D13C6 represents a novel and promising radiotracer for immuno-PET imaging of PDGFRα in metastatic papillary thyroid cancer. ADVANCES IN KNOWLEDGE AND IMPLICATIONS FOR PATIENT CARE The presented work has the potential to allow physicians to identify papillary thyroid cancer patients at risk of metastases by using the novel immuno-PET imaging assay based on PDGFRα-targeting antibody [64Cu]Cu-NOTA-D13C6.
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Affiliation(s)
- Michael Wagner
- University of Alberta, Department of Oncology, 11560 University Ave, Edmonton, AB T6G 1Z2, Canada
| | - Melinda Wuest
- University of Alberta, Department of Oncology, 11560 University Ave, Edmonton, AB T6G 1Z2, Canada
| | - Ingrit Hamann
- University of Alberta, Department of Oncology, 11560 University Ave, Edmonton, AB T6G 1Z2, Canada
| | - Ana Lopez-Campistrous
- University of Alberta, Department of Surgery, 2D4.41 Walter Mackenzie Centre 8440- 112 Street, Edmonton, AB T6G 2B7, Canada
| | - Todd P W McMullen
- University of Alberta, Department of Oncology, 11560 University Ave, Edmonton, AB T6G 1Z2, Canada; University of Alberta, Department of Surgery, 2D4.41 Walter Mackenzie Centre 8440- 112 Street, Edmonton, AB T6G 2B7, Canada.
| | - Frank Wuest
- University of Alberta, Department of Oncology, 11560 University Ave, Edmonton, AB T6G 1Z2, Canada.
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Larson SM, Osborne JR, Grewal RK, Tuttle RM. Redifferentiating Thyroid Cancer: Selumetinib-enhanced Radioiodine Uptake in Thyroid Cancer. Mol Imaging Radionucl Ther 2017; 26:80-86. [PMID: 28117292 PMCID: PMC5283711 DOI: 10.4274/2017.26.suppl.09] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
In a recent article, we reported a restorative therapeutic intervention that turned individual thyroid cancer lesions into more efficient tissues for taking up radioactive iodine (RAI), resulting in clinically significant and durable responses. A group of Iodine-131 refractory thyroid cancer patients were treated with the MEK tyrosine kinase inhibitor (TKI) selumetinib, and RAI uptake was restored in a subset of patients. We employed Iodine-124 positron emission tomography to measure radiation absorbed dose, on a lesion by lesion basis. The process can be thought of as a re-differentiation of the cancer toward a more nearly normal state most like the tissue from which the cancer arose. Remarkably, in its own way, a change was detected within a few weeks of treatment, restoring uptake with therapeutically effective levels of RAI and in some patients, previously completely refractory to radioiodine treatment. In this article, we summarize the basic work that led to this seminal study, and make the case for lesional dosimetry in thyroid cancer with Iodine-124 as a new optimal radiotracer for precision medicine in patients with well differentiated thyroid cancer.
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Affiliation(s)
- Steven M Larson
- Memorial Sloan Kettering Cancer Center, New York, USA, Phone: 646888359, E-mail:
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15
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Laforest R, Dehdashti F, Liu Y, Frye J, Frye S, Luehmann H, Sultan D, Shan JS, Freimark BD, Siegel BA. First-in-Man Evaluation of 124I-PGN650: A PET Tracer for Detecting Phosphatidylserine as a Biomarker of the Solid Tumor Microenvironment. Mol Imaging 2017; 16:1536012117733349. [PMID: 29037107 PMCID: PMC5648081 DOI: 10.1177/1536012117733349] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Revised: 08/17/2017] [Accepted: 08/20/2017] [Indexed: 11/24/2022] Open
Abstract
PURPOSE PGN650 is a F(ab')2 antibody fragment that targets phosphatidylserine (PS), a marker normally absent that becomes exposed on tumor cells and tumor vasculature in response to oxidative stress and increases in response to therapy. PGN650 was labeled with 124I to create a positron emission tomography (PET) agent as an in vivo biomarker for tumor microenvironment and response to therapy. In this phase 0 study, we evaluated the pharmacokinetics, safety, radiation dosimetry, and tumor targeting of this tracer in a cohort of patients with cancer. METHODS Eleven patients with known solid tumors received approximately 140 MBq (3.8 mCi) 124I-PGN650 intravenously and underwent positron emission tomography-computed tomography (PET/CT) approximately 1 hour, 3 hours, and either 24 hours or 48 hours later to establish tracer kinetics for the purpose of calculating radiation dosimetry (from integration of the organ time-activity curves and OLINDA/EXM using the adult male and female models). RESULTS Known tumor foci demonstrated mildly increased uptake, with the highest activity at the latest imaging time. There were no unexpected adverse events. The liver was the organ receiving the highest radiation dose (0.77 mGy/MBq); the effective dose was 0.41 mSv/MBq. CONCLUSION Although 124I-PGN650 is safe for human PET imaging, the tumor targeting with this agent in patients was less than previously observed in animal studies.
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Affiliation(s)
- Richard Laforest
- Division of Radiological Sciences, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, MO, USA
- Alvin J. Siteman Cancer Center, Washington University School of Medicine, St Louis, MO, USA
- Division of Nuclear Medicine, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, MO, USA
| | - Farrokh Dehdashti
- Alvin J. Siteman Cancer Center, Washington University School of Medicine, St Louis, MO, USA
- Division of Nuclear Medicine, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, MO, USA
| | - Yongjian Liu
- Division of Radiological Sciences, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, MO, USA
- Alvin J. Siteman Cancer Center, Washington University School of Medicine, St Louis, MO, USA
| | - Jennifer Frye
- Division of Nuclear Medicine, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, MO, USA
| | - Sarah Frye
- Division of Nuclear Medicine, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, MO, USA
| | - Hannah Luehmann
- Division of Radiological Sciences, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, MO, USA
| | - Deborah Sultan
- Division of Radiological Sciences, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, MO, USA
| | | | | | - Barry A. Siegel
- Alvin J. Siteman Cancer Center, Washington University School of Medicine, St Louis, MO, USA
- Division of Nuclear Medicine, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, MO, USA
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16
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Mahajan S, Divgi CR. The role of iodine-124 positron emission tomography in molecular imaging. Clin Transl Imaging 2016. [DOI: 10.1007/s40336-016-0186-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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17
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Cheal SM, Xu H, Guo HF, Lee SG, Punzalan B, Chalasani S, Fung EK, Jungbluth A, Zanzonico PB, Carrasquillo JA, O'Donoghue J, Smith-Jones PM, Wittrup KD, Cheung NKV, Larson SM. Theranostic pretargeted radioimmunotherapy of colorectal cancer xenografts in mice using picomolar affinity ⁸⁶Y- or ¹⁷⁷Lu-DOTA-Bn binding scFv C825/GPA33 IgG bispecific immunoconjugates. Eur J Nucl Med Mol Imaging 2015; 43:925-937. [PMID: 26596724 DOI: 10.1007/s00259-015-3254-8] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Accepted: 11/02/2015] [Indexed: 12/25/2022]
Abstract
PURPOSE GPA33 is a colorectal cancer (CRC) antigen with unique retention properties after huA33-mediated tumor targeting. We tested a pretargeted radioimmunotherapy (PRIT) approach for CRC using a tetravalent bispecific antibody with dual specificity for GPA33 tumor antigen and DOTA-Bn-(radiolanthanide metal) complex. METHODS PRIT was optimized in vivo by titrating sequential intravenous doses of huA33-C825, the dextran-based clearing agent, and the C825 haptens (177)Lu-or (86)Y-DOTA-Bn in mice bearing the SW1222 subcutaneous (s.c.) CRC xenograft model. RESULTS Using optimized PRIT, therapeutic indices (TIs) for tumor radiation-absorbed dose of 73 (tumor/blood) and 12 (tumor/kidney) were achieved. Estimated absorbed doses (cGy/MBq) to tumor, blood, liver, spleen, and kidney for single-cycle PRIT were 65.8, 0.9 (TI 73), 6.3 (TI 10), 6.6 (TI 10), and 5.3 (TI 12), respectively. Two cycles of PRIT (66.6 or 111 MBq (177)Lu-DOTA-Bn) were safe and effective, with a complete response of established s.c. tumors (100 - 700 mm(3)) in nine of nine mice, with two mice alive without recurrence at >140 days. Tumor log kill in this model was estimated to be 2.1 - 3.0 based on time to 500-mm(3) tumor recurrence. In addition, PRIT dosimetry/diagnosis was performed by PET imaging of the positron-emitting DOTA hapten (86)Y-DOTA-Bn. CONCLUSION We have developed anti-GPA33 PRIT as a triple-step theranostic strategy for preclinical detection, dosimetry, and safe targeted radiotherapy of established human colorectal mouse xenografts.
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Affiliation(s)
- Sarah M Cheal
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY, USA.,Molecular Pharmacology and Chemistry Program, Memorial Sloan Kettering Cancer Center, 415 E. 68th Street, Z-2064, New York, NY, 10065, USA
| | - Hong Xu
- Department of Pediatrics, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Hong-Fen Guo
- Department of Pediatrics, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Sang-Gyu Lee
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY, USA.,Molecular Pharmacology and Chemistry Program, Memorial Sloan Kettering Cancer Center, 415 E. 68th Street, Z-2064, New York, NY, 10065, USA
| | - Blesida Punzalan
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY, USA.,Molecular Pharmacology and Chemistry Program, Memorial Sloan Kettering Cancer Center, 415 E. 68th Street, Z-2064, New York, NY, 10065, USA
| | - Sandhya Chalasani
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Edward K Fung
- Molecular Pharmacology and Chemistry Program, Memorial Sloan Kettering Cancer Center, 415 E. 68th Street, Z-2064, New York, NY, 10065, USA.,Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Achim Jungbluth
- Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Pat B Zanzonico
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Jorge A Carrasquillo
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Joseph O'Donoghue
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Peter M Smith-Jones
- Department of Psychiatry and Behavioral Science, Stony Brook University, Stony Brook, NY, USA.,Department of Radiology, Stony Brook University, Stony Brook, NY, USA
| | - K Dane Wittrup
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA.,Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA.,Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Nai-Kong V Cheung
- Molecular Pharmacology and Chemistry Program, Memorial Sloan Kettering Cancer Center, 415 E. 68th Street, Z-2064, New York, NY, 10065, USA.,Department of Pediatrics, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Steven M Larson
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY, USA. .,Molecular Pharmacology and Chemistry Program, Memorial Sloan Kettering Cancer Center, 415 E. 68th Street, Z-2064, New York, NY, 10065, USA.
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18
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Correlations between ASCC3 Gene Polymorphisms and Chronic Hepatitis B in a Chinese Han Population. PLoS One 2015; 10:e0141861. [PMID: 26536629 PMCID: PMC4633062 DOI: 10.1371/journal.pone.0141861] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2015] [Accepted: 10/14/2015] [Indexed: 01/01/2023] Open
Abstract
We have previously identified 8 SNPs in Han Chinese HBV carriers that are associated with disease progression. Although not well studied, genetic factors may also play a significant role in developing chronic HBV disease after exposure. We extend the effect of these eight SNPs on persistent HBV infection in this study. A total of 875 unrelated Han Chinese, 493 chronic hepatitis B subjects (CHB) and 382 HBV clearance individuals (Clear), were recruited from Hubei Province from September 2007 to March 2010. SNPs were verified by using TaqMan 7900HT Sequence Detection System. By using multiple logistic regression analysis, each of the 8 SNP associations was tested using 3 different genetic models (Dominant, Recessive and Additive model), in 4 types of analyses (full sample, men, women, age stratified). A Bonferroni correction was used to account for multiple statistical tests for each SNP association (P<0.05/8 = 0.0063). A significant correlation was observed at SNP rs10485138 located in ASCC3 gene in female patients (OR, 0.445; 95% CI, 0.253–0.784; P = 0.005). Females bearing C allele infected by HBV had an increased susceptibility to CHB compared with those T allele carriers. Our results indicated that SNP rs10485138 located in ASCC3 gene was associated with persistent HBV infection in Han Chinese.
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19
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PET-based compartmental modeling of (124)I-A33 antibody: quantitative characterization of patient-specific tumor targeting in colorectal cancer. Eur J Nucl Med Mol Imaging 2015; 42:1700-1706. [PMID: 26194713 DOI: 10.1007/s00259-015-3061-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2015] [Accepted: 04/01/2015] [Indexed: 10/23/2022]
Abstract
PURPOSE The molecular specificity of monoclonal antibodies (mAbs) directed against tumor antigens has proven effective for targeted therapy of human cancers, as shown by a growing list of successful antibody-based drug products. We describe a novel, nonlinear compartmental model using PET-derived data to determine the "best-fit" parameters and model-derived quantities for optimizing biodistribution of intravenously injected (124)I-labeled antitumor antibodies. METHODS As an example of this paradigm, quantitative image and kinetic analyses of anti-A33 humanized mAb (also known as "A33") were performed in 11 colorectal cancer patients. Serial whole-body PET scans of (124)I-labeled A33 and blood samples were acquired and the resulting tissue time-activity data for each patient were fit to a nonlinear compartmental model using the SAAM II computer code. RESULTS Excellent agreement was observed between fitted and measured parameters of tumor uptake, "off-target" uptake in bowel mucosa, blood clearance, tumor antigen levels, and percent antigen occupancy. CONCLUSION This approach should be generally applicable to antibody-antigen systems in human tumors for which the masses of antigen-expressing tumor and of normal tissues can be estimated and for which antibody kinetics can be measured with PET. Ultimately, based on each patient's resulting "best-fit" nonlinear model, a patient-specific optimum mAb dose (in micromoles, for example) may be derived.
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20
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Merten H, Brandl F, Plückthun A, Zangemeister-Wittke U. Antibody-Drug Conjugates for Tumor Targeting-Novel Conjugation Chemistries and the Promise of non-IgG Binding Proteins. Bioconjug Chem 2015; 26:2176-85. [PMID: 26086208 DOI: 10.1021/acs.bioconjchem.5b00260] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Antibody-drug conjugates (ADCs) have emerged as a promising class of anticancer agents, combining the specificity of antibodies for tumor targeting and the destructive potential of highly potent drugs as payload. An essential component of these immunoconjugates is a bifunctional linker capable of reacting with the antibody and the payload to assemble a functional entity. Linker design is fundamental, as it must provide high stability in the circulation to prevent premature drug release, but be capable of releasing the active drug inside the target cell upon receptor-mediated endocytosis. Although ADCs have demonstrated an increased therapeutic window, compared to conventional chemotherapy in recent clinical trials, therapeutic success rates are still far from optimal. To explore other regimes of half-life variation and drug conjugation stoichiometries, it is necessary to investigate additional binding proteins which offer access to a wide range of formats, all with molecularly defined drug conjugation. Here, we delineate recent progress with site-specific and biorthogonal conjugation chemistries, and discuss alternative, biophysically more stable protein scaffolds like Designed Ankyrin Repeat Proteins (DARPins), which may provide such additional engineering opportunities for drug conjugates with improved pharmacological performance.
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Affiliation(s)
- Hannes Merten
- Department of Biochemistry, University of Zurich , Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
| | - Fabian Brandl
- Department of Biochemistry, University of Zurich , Winterthurerstrasse 190, CH-8057 Zurich, Switzerland.,Institute of Pharmacology, University of Bern , Inselspital INO-F, CH-3010 Bern, Switzerland
| | - Andreas Plückthun
- Department of Biochemistry, University of Zurich , Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
| | - Uwe Zangemeister-Wittke
- Department of Biochemistry, University of Zurich , Winterthurerstrasse 190, CH-8057 Zurich, Switzerland.,Institute of Pharmacology, University of Bern , Inselspital INO-F, CH-3010 Bern, Switzerland
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Abstract
The eradication of cancer remains a vexing problem despite recent advances in our understanding of the molecular basis of neoplasia. One therapeutic approach that has demonstrated potential involves the selective targeting of radionuclides to cancer-associated cell surface antigens using monoclonal antibodies. Such radioimmunotherapy (RIT) permits the delivery of a high dose of therapeutic radiation to cancer cells, while minimizing the exposure of normal cells. Although this approach has been investigated for several decades, the cumulative advances in cancer biology, antibody engineering and radiochemistry in the past decade have markedly enhanced the ability of RIT to produce durable remissions of multiple cancer types.
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Affiliation(s)
- Steven M Larson
- Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, New York 10065, USA
| | - Jorge A Carrasquillo
- Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, New York 10065, USA
| | - Nai-Kong V Cheung
- 1] Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, New York 10065, USA. [2]
| | - Oliver W Press
- 1] Fred Hutchinson Cancer Research Center, 1100 Fairview Avenue North, P.O. BOX 19024, Seattle, Washington 98109, USA. [2]
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22
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Abstract
Imaging has played an important part in the diagnosis of disease and development of the understanding of the underlying disease mechanisms and is now poised to make an impact in the development of new pharmaceuticals. This chapter discusses the underlying technologies that make the field ready for this challenge. In particular, the potentials of magnetic resonance imaging and functional magnetic resonance imaging are outlined, including the new methods developed to provide additional information from the scans carried out. The field of nuclear medicine has seen a rapid increase in interest as advances in radiochemistry have enabled a wide range of new radiotracers to be synthesised.
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Affiliation(s)
- James Nairne
- GE Healthcare, The Grove Centre, Amersham, Buckinghamshire, United Kingdom
| | - Peter B Iveson
- GE Healthcare, The Grove Centre, Amersham, Buckinghamshire, United Kingdom
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23
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Wållberg H, Ståhl S. Design and evaluation of radiolabeled tracers for tumor imaging. Biotechnol Appl Biochem 2014; 60:365-83. [PMID: 24033592 DOI: 10.1002/bab.1111] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2012] [Accepted: 02/20/2013] [Indexed: 12/22/2022]
Abstract
The growing understanding of tumor biology and the identification of tumor-specific genetic and molecular alterations, such as the overexpression of membrane receptors and other proteins, allows for personalization of patient management using targeted therapies. However, this puts stringent demands on the diagnostic tools used to identify patients who are likely to respond to a particular treatment. Radionuclide molecular imaging is a promising noninvasive method to visualize and characterize the expression of such targets. A number of different proteins, from full-length antibodies and their derivatives to small scaffold proteins and peptide receptor-ligands, have been applied to molecular imaging, each demonstrating strengths and weaknesses. Here, we discuss the concept of molecular targeting and, in particular, molecular imaging of cancer-associated targets. Additionally, we describe important biotechnological considerations and desired features when designing and developing tracers for radionuclide molecular imaging.
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Affiliation(s)
- Helena Wållberg
- Division of Molecular Biotechnology, School of Biotechnology, AlbaNova University Center, KTH Royal Institute of Technology, Stockholm, Sweden
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Ciprotti M, Chong G, Gan HK, Chan A, Murone C, MacGregor D, Lee FT, Johns TG, Heath JK, Ernst M, Burgess AW, Scott AM. Quantitative intratumoural microdistribution and kinetics of (131)I-huA33 antibody in patients with colorectal carcinoma. EJNMMI Res 2014; 4:22. [PMID: 24995151 PMCID: PMC4070025 DOI: 10.1186/s13550-014-0022-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2014] [Accepted: 04/07/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The ability of recombinant antibodies to adequately penetrate into tumours is a key factor in achieving therapeutic effect; however, the behaviour of antibodies at a cellular level in tumours is poorly understood. The purpose of this study was to investigate those factors that influence the macroscopic and microscopic intratumoural distribution of an IgG1-humanized antibody, huA33, in colorectal tumours. METHODS Twelve patients were infused with radiolabelled huA33 at 7 days prior to elective surgery for colorectal carcinoma. Macroscopic huA33 uptake was determined by both gamma well counter and autoradiography measurements of the resected tumour specimens. Microscopic uptake was then quantitated at a cellular level and compared to vascular penetrance. The impact of variation in tumour antigen (GPA33) expression, tumour size, specimen type (primary vs metastatic), presence of macroscopic necrosis, and tumour vasculature on huA33 uptake were examined. RESULTS The I-huA33 uptake in whole tumour sections was (mean ± SD) 5.13 ± 2.71 × 10(-3)% injected dose per gram (ID/g). GPA33 was expressed in all viable tumour cells, and huA33 uptake was excellent regardless of tumour size and specimen type. In tumours with macroscopically evident central necrosis (n = 5), huA33 uptake in tumour necrotic centres was lower than in viable peripheries (0.606 ± 0.493 vs 2.98 ± 2.17 × 10(-3)%ID, p = 0.06). However, when corrected for low cell viability in necrotic centres, uptake of huA33 at the cellular level was highly comparable to that in the more viable tumour periphery (7.10 ± 5.10 × 10(-9) vs 3.82 ± 3.67 × 10(-9)%ID/cell, p = 0.4). In the five patients who exhibited macroscopic necrosis in their tumours, huA33 showed excellent tissue penetration, with a maximum penetration distance of 26 μm in peripheral tumour regions and 118 μm in central regions. No correlation was observed between (131)I-huA33 uptake in tumour on a cellular basis and tumour vascularity. CONCLUSIONS In patients with colorectal carcinoma, monoclonal antibody huA33 effectively targets viable tumour cells in all cellular milieus examined, including effective penetration into necrotic tumour centres, a novel and therapeutically important finding.
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Affiliation(s)
- Marika Ciprotti
- Ludwig Institute for Cancer Research, Austin Health, Melbourne 3084, Australia
| | - Geoffrey Chong
- Ludwig Institute for Cancer Research, Austin Health, Melbourne 3084, Australia
| | - Hui K Gan
- Ludwig Institute for Cancer Research, Austin Health, Melbourne 3084, Australia
| | - Anthony Chan
- Ludwig Institute for Cancer Research, Austin Health, Melbourne 3084, Australia
| | - Carmel Murone
- Ludwig Institute for Cancer Research, Austin Health, Melbourne 3084, Australia ; Department of Anatomical Pathology, Austin Health, Melbourne 3084, Australia
| | - Duncan MacGregor
- Department of Anatomical Pathology, Austin Health, Melbourne 3084, Australia
| | - Fook-Thean Lee
- Ludwig Institute for Cancer Research, Austin Health, Melbourne 3084, Australia
| | - Terrance G Johns
- Monash Institute for Medical Research, Melbourne 3168, Australia
| | - Joan K Heath
- Ludwig Institute for Cancer Research, Austin Health, Melbourne 3084, Australia ; Walter and Eliza Hall Institute of Medical Research, Melbourne 3052, Australia
| | - Matthias Ernst
- Ludwig Institute for Cancer Research, Austin Health, Melbourne 3084, Australia ; Walter and Eliza Hall Institute of Medical Research, Melbourne 3052, Australia
| | - Antony W Burgess
- Walter and Eliza Hall Institute of Medical Research, Melbourne 3052, Australia
| | - Andrew M Scott
- Ludwig Institute for Cancer Research, Austin Health, Melbourne 3084, Australia ; Department of Nuclear Medicine and Centre for PET, Austin Health, Melbourne 3084, Australia
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Cheal SM, Punzalan B, Doran MG, Evans MJ, Osborne JR, Lewis JS, Zanzonico P, Larson SM. Pairwise comparison of 89Zr- and 124I-labeled cG250 based on positron emission tomography imaging and nonlinear immunokinetic modeling: in vivo carbonic anhydrase IX receptor binding and internalization in mouse xenografts of clear-cell renal cell carcinoma. Eur J Nucl Med Mol Imaging 2014; 41:985-94. [PMID: 24604591 DOI: 10.1007/s00259-013-2679-1] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2013] [Accepted: 12/20/2013] [Indexed: 12/17/2022]
Abstract
PURPOSE The PET tracer, (124)I-cG250, directed against carbonic anhydrase IX (CAIX) shows promise for presurgical diagnosis of clear-cell renal cell carcinoma (ccRCC) (Divgi et al. in Lancet Oncol 8:304-310, 2007; Divgi et al. in J Clin Oncol 31:187-194, 2013). The radiometal (89)Zr, however, may offer advantages as a surrogate PET nuclide over (124)I in terms of greater tumor uptake and retention (Rice et al. in Semin Nucl Med 41:265-282, 2011). We have developed a nonlinear immunokinetic model to facilitate a quantitative comparison of absolute uptake and antibody turnover between (124)I-cG250 and (89)Zr-cG250 using a human ccRCC xenograft tumor model in mice. We believe that this unique model better relates quantitative imaging data to the salient biological features of tumor antibody-antigen binding and turnover. METHODS We conducted experiments with (89)Zr-cG250 and (124)I-cG250 using a human ccRCC cell line (SK-RC-38) to characterize the binding affinity and internalization kinetics of the two tracers in vitro. Serial PET imaging was performed in mice bearing subcutaneous ccRCC tumors to simultaneously detect and quantify time-dependent tumor uptake in vivo. Using the known specific activities of the two tracers, the equilibrium rates of antibody internalization and turnover in the tumors were derived from the PET images using nonlinear compartmental modeling. RESULTS The two tracers demonstrated virtually identical tumor cell binding and internalization but showed markedly different retentions in vitro. Superior PET images were obtained using (89)Zr-cG250, owing to the more prolonged trapping of the radiolabel in the tumor and simultaneous washout from normal tissues. Estimates of cG250/CAIX complex turnover were 1.35 - 5.51 × 10(12) molecules per hour per gram of tumor (20 % of receptors internalized per hour), and the ratio of (124)I/(89)Zr atoms released per unit time by tumor was 17.5. CONCLUSION Pairwise evaluation of (89)Zr-cG250 and (124)I-cG250 provided the basis for a nonlinear immunokinetic model which yielded quantitative information about the binding and internalization of radioantibody bound to CAIX on tumor cells in vivo. (89)Zr-cG250 is likely to provide high-quality PET images and may be a useful tool to quantify CAIX/cG250 receptor turnover and cG250-accessible antigen density noninvasively in humans.
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Affiliation(s)
- Sarah M Cheal
- Department of Radiology, Memorial Sloan-Kettering Cancer Center, New York, NY, USA
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26
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Li C, Chacko AM, Hu J, Hasegawa K, Swails J, Grasso L, El-Deiry WS, Nicolaides N, Muzykantov VR, Divgi CR, Coukos G. Antibody-based tumor vascular theranostics targeting endosialin/TEM1 in a new mouse tumor vascular model. Cancer Biol Ther 2014; 15:443-51. [PMID: 24553243 DOI: 10.4161/cbt.27825] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
UNLABELLED Tumor endothelial marker 1 (TEM1, endosialin) is a tumor vascular marker with significant diagnostic and therapeutic potential. However, in vivo small animal models to test affinity reagents specifically targeted to human (h)TEM1 are limited. We describe a new mouse tumor model where tumor vascular endothelial cells express hTEM1 protein. METHODS Immortalized murine endothelial cells MS1 were engineered to express hTEM1 and firefly luciferase and were inoculated in nude mice either alone, to form hemangioma-like endothelial grafts, or admixed with ID8 ovarian tumor cells, to form chimeric endothelial-tumor cell grafts. MORAb-004, a monoclonal humanized IgG 1 antibody specifically recognizing human TEM1 was evaluated for targeted theranostic applications, i.e., for its ability to affect vascular grafts expressing hTEM1 as well as being a tool for molecular positron emission tomography (PET) imaging. RESULTS Naked MORAb-004 treatment of mice bearing angioma grafts or chimeric endothelial-tumor grafts significantly suppressed the ability of hTEM1-positive endothelial cells, but not control endothelial cells, to form grafts and dramatically suppressed local angiogenesis. In addition, highly efficient radioiodination of MORAb-004 did not impair its affinity for hTEM1, and [ (124)I]-MORAb-004-PET enabled non-invasive visualization of tumors enriched with hTEM1-positive, but not hTEM1 negative vasculature with high degree of specificity and sensitivity. CONCLUSION The development of a new robust endothelial graft model expressing human tumor vascular proteins will help accelerate the development of novel theranostics targeting the tumor vasculature, which exhibit affinity specifically to human targets but not their murine counterparts. Our results also demonstrate the theranostic potential of MORAb-004 as PET imaging tracer and naked antibody therapy for TEM1-positive tumor.
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Affiliation(s)
- Chunsheng Li
- Ovarian Cancer Research Center; University of Pennsylvania; Philadelphia, PA USA
| | - Ann-Marie Chacko
- Institute for Translational Medicine and Therapeutics; University of Pennsylvania; Philadelphia, PA USA; Division of Nuclear Medicine and Clinical Molecular Imaging; Department of Radiology; University of Pennsylvania; Philadelphia, PA USA
| | - Jia Hu
- Ovarian Cancer Research Center; University of Pennsylvania; Philadelphia, PA USA
| | - Kosei Hasegawa
- Ovarian Cancer Research Center; University of Pennsylvania; Philadelphia, PA USA
| | - Jennifer Swails
- Ovarian Cancer Research Center; University of Pennsylvania; Philadelphia, PA USA
| | | | - Wafik S El-Deiry
- Department of Medicine, Hematology/Oncology; University of Pennsylvania; Philadelphia, PA USA
| | | | - Vladimir R Muzykantov
- Institute for Translational Medicine and Therapeutics; University of Pennsylvania; Philadelphia, PA USA
| | - Chaitanya R Divgi
- Division of Nuclear Medicine and Clinical Molecular Imaging; Department of Radiology; University of Pennsylvania; Philadelphia, PA USA
| | - George Coukos
- Ovarian Cancer Research Center; University of Pennsylvania; Philadelphia, PA USA
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27
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Chacko AM, Li C, Nayak M, Mikitsh JL, Hu J, Hou C, Grasso L, Nicolaides NC, Muzykantov VR, Divgi CR, Coukos G. Development of 124I immuno-PET targeting tumor vascular TEM1/endosialin. J Nucl Med 2014; 55:500-507. [PMID: 24525208 DOI: 10.2967/jnumed.113.121905] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
UNLABELLED Tumor endothelial marker 1 (TEM1/endosialin) is a tumor vascular marker highly overexpressed in multiple human cancers with minimal expression in normal adult tissue. In this study, we report the preparation and evaluation of (124)I-MORAb-004, a humanized monoclonal antibody targeting an extracellular epitope of human TEM1 (hTEM1), for its ability to specifically and sensitively detect vascular cells expressing hTEM1 in vivo. METHODS MORAb-004 was directly iodinated with (125)I and (124)I, and in vitro binding and internalization parameters were characterized. The in vivo behavior of radioiodinated MORAb-004 was characterized in mice bearing subcutaneous ID8 tumors enriched with mouse endothelial cells expressing hTEM1 and by biodistribution and small-animal immuno-PET studies. RESULTS MORAb-004 was radiolabeled with high efficiency and isolated in high purity. In vitro studies demonstrated specific and sensitive binding of MORAb-004 to MS1 mouse endothelial cells expressing hTEM1, with no binding to control MS1 cells. (125)I-MORAb-004 and (124)I-MORAb-004 both had an immunoreactivity of approximately 90%. In vivo biodistribution experiments revealed rapid, highly specific and sensitive uptake of MORAb-004 in MS1-TEM1 tumors at 4 h (153.2 ± 22.2 percentage injected dose per gram [%ID/g]), 24 h (127.1 ± 42.9 %ID/g), 48 h (130.3 ± 32.4 %ID/g), 72 h (160.9 ± 32.1 %ID/g), and 6 d (10.7 ± 1.8 %ID/g). Excellent image contrast was observed with (124)I-immuno-PET. MORAb-004 uptake was statistically higher in TEM1-positive tumors than in control tumors. Binding specificity was confirmed by blocking studies using excess nonlabeled MORAb-004. CONCLUSION In our preclinical model, with hTEM1 exclusively expressed on engineered murine endothelial cells that integrate into the tumor vasculature, (124)I-MORAb-004 displays high tumor-to-background tissue contrast for detection of hTEM1 in easily accessible tumor vascular compartments. These studies strongly suggest the clinical utility of (124)I-MORAb-004 immuno-PET in assessing TEM1 tumor-status.
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Affiliation(s)
- Ann-Marie Chacko
- Nuclear Medicine & Clinical Molecular Imaging, Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania.,Institute for Translational Medicine and Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Chunsheng Li
- Ovarian Cancer Research Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Madhura Nayak
- Nuclear Medicine & Clinical Molecular Imaging, Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - John L Mikitsh
- Nuclear Medicine & Clinical Molecular Imaging, Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Jia Hu
- Ovarian Cancer Research Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Catherine Hou
- Nuclear Medicine & Clinical Molecular Imaging, Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | | | | | - Vladimir R Muzykantov
- Institute for Translational Medicine and Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Chaitanya R Divgi
- Nuclear Medicine & Clinical Molecular Imaging, Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - George Coukos
- Ovarian Cancer Research Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
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Mortimer JE, Bading JR, Colcher DM, Conti PS, Frankel PH, Carroll MI, Tong S, Poku E, Miles JK, Shively JE, Raubitschek AA. Functional imaging of human epidermal growth factor receptor 2-positive metastatic breast cancer using (64)Cu-DOTA-trastuzumab PET. J Nucl Med 2013; 55:23-9. [PMID: 24337604 DOI: 10.2967/jnumed.113.122630] [Citation(s) in RCA: 116] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
UNLABELLED Women with human epidermal growth factor receptor 2 (HER2)-positive breast cancer are candidates for treatment with the anti-HER2 antibody trastuzumab. Assessment of HER2 status in recurrent disease is usually made by core needle biopsy of a single lesion, which may not represent the larger tumor mass or other sites of disease. Our long-range goal is to develop PET of radiolabeled trastuzumab for systemically assessing tumor HER2 expression and identifying appropriate use of anti-HER2 therapies. The purpose of this study was to evaluate PET/CT of (64)Cu-DOTA-trastuzumab for detecting and measuring tumor uptake of trastuzumab in patients with HER2-positive metastatic breast cancer. METHODS Eight women with biopsy-confirmed HER2-positive metastatic breast cancer and no anti-HER2 therapy for 4 mo or longer underwent complete staging, including (18)F-FDG PET/CT. For 6 of the 8 patients, (64)Cu-DOTA-trastuzumab injection (364-512 MBq, 5 mg of trastuzumab) was preceded by trastuzumab infusion (45 mg). PET/CT (PET scan duration 1 h) was performed 21-25 (day 1) and 47-49 (day 2) h after (64)Cu-DOTA-trastuzumab injection. Scan fields of view were chosen on the basis of (18)F-FDG PET/CT. Tumor detection sensitivity and uptake analyses were limited to lesions identifiable on CT; lesions visualized relative to adjacent tissue on PET were considered PET-positive. Radiolabel uptake in prominent lesions was measured as maximum single-voxel standardized uptake value (SUVmax). RESULTS Liver uptake of (64)Cu was reduced approximately 75% with the 45-mg trastuzumab predose, without significant effect on tumor uptake. The study included 89 CT-positive lesions. Detection sensitivity was 77%, 89%, and 93% for day 1, day 2, and (18)F-FDG, respectively. On average, tumor uptake was similar for (64)Cu-DOTA-trastuzumab and (18)F-FDG (SUVmax and range, 8.1 and 3.0-22.5 for day 1 [n = 48]; 8.9 and 0.9-28.9 for day 2 [n = 38]; 9.7 and 3.3-25.4 for (18)F-FDG [n = 56]), but same-lesion SUVmax was not correlated between the 2 radiotracers. No toxicities were observed, and estimated radiation dose from (64)Cu-DOTA-trastuzumab was similar to (18)F-FDG. CONCLUSION (64)Cu-DOTA-trastuzumab visualizes HER2-positive metastatic breast cancer with high sensitivity and is effective in surveying disseminated disease. A 45-mg trastuzumab predose provides a (64)Cu-DOTA-trastuzumab biodistribution favorable for tumor imaging. (64)Cu-DOTA-trastuzumab PET/CT warrants further evaluation for assessing tumor HER2 expression and individualizing treatments that include trastuzumab.
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Affiliation(s)
- Joanne E Mortimer
- Department of Medical Oncology and Experimental Therapeutics, City of Hope, Duarte, California
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Bai B, Bading J, Conti PS. Tumor quantification in clinical positron emission tomography. Am J Cancer Res 2013; 3:787-801. [PMID: 24312151 PMCID: PMC3840412 DOI: 10.7150/thno.5629] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2012] [Accepted: 02/11/2013] [Indexed: 12/18/2022] Open
Abstract
Positron emission tomography (PET) is used extensively in clinical oncology for tumor detection, staging and therapy response assessment. Quantitative measurements of tumor uptake, usually in the form of standardized uptake values (SUVs), have enhanced or replaced qualitative interpretation. In this paper we review the current status of tumor quantification methods and their applications to clinical oncology. Factors that impede quantitative assessment and limit its accuracy and reproducibility are summarized, with special emphasis on SUV analysis. We describe current efforts to improve the accuracy of tumor uptake measurements, characterize overall metabolic tumor burden and heterogeneity of tumor uptake, and account for the effects of image noise. We also summarize recent developments in PET instrumentation and image reconstruction and their impact on tumor quantification. Finally, we offer our assessment of the current development needs in PET tumor quantification, including practical techniques for fully quantitative, pharmacokinetic measurements.
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Zhou Y, Baidoo KE, Brechbiel MW. Mapping biological behaviors by application of longer-lived positron emitting radionuclides. Adv Drug Deliv Rev 2013; 65:1098-111. [PMID: 23123291 DOI: 10.1016/j.addr.2012.10.012] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2012] [Revised: 10/17/2012] [Accepted: 10/23/2012] [Indexed: 02/08/2023]
Abstract
With the technological development of positron emission tomography (PET) and the advent of novel antibody-directed drug delivery systems, longer-lived positron-emitting radionuclides are moving to the forefront to take important roles in tracking the distribution of biotherapeutics such as antibodies, and for monitoring biological processes and responses. Longer half-life radionuclides possess advantages of convenient on-site preparation procedures for both clinical and non-clinical applications. The suitability of the long half-life radionuclides for imaging intact monoclonal antibodies (mAbs) and their respective fragments, which have inherently long biological half-lives, has attracted increased interest in recent years. In this review, we provide a survey of the recent literature as it applies to the development of nine-selected longer-lived positron emitters with half-lives of 9-140h (e.g., (124)I, (64)Cu, (86)Y and (89)Zr), and describe the biological behaviors of radionuclide-labeled mAbs with respect to distribution and targeting characteristics, potential toxicities, biological applications, and clinical translation potentials.
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Key Words
- (124)I
- (64)Cu
- (86)Y
- (89)Zr
- 1,4,7,10-tetraazacyclododecane-N,N′,N″,N″′-tetraacetic acid
- 1,4,7-triazacyclononane-N,N′,N″-1,4,7-triacetic acid
- 1-N-(4-aminobenzyl)-3,6,10,13,16,19-hexaazabicyclo[6.6.6]eicosane-1,8-diamine
- 1-oxa-4,7,1-tetraazacyclododecane-5-S-(4-isothiocyanatobenzyl)-4,7,10-triacetic acid
- 3,6,9,15-tetraazabicyclo[9.3.1]-pentadeca-1(15),11,13-triene-4-S-(4-isothiocyanatobenzyl)-3,6,9-triacetic acid
- CHX-A″-DTPA
- DOTA
- DOTA-DPhe1-Tyr3-octreotide
- DOTATOC
- DTPA
- HPMA
- Immuno-PET
- Monoclonal antibodies
- N-(2-hydroxypropyl)-methacrylamide
- N-[R-2-amino-3-(p-isothiocyanato-phenyl)propyl]-trans-(S,S)-cyclohexane-1,2-diamine-N,N,N′,N″,N″-pentaacetic acid
- NOTA
- Oncology
- PIB
- PIP
- Radioimmunoimaging
- SATA
- SarAr
- bispecific monoclonal antibody
- bsMAb
- diethylenetriaminepentaacetic acid
- p-SCN-Bn-PCTA
- p-SCN-Bn-oxo-DO3A
- p-iodobenzoate
- para-iodophenyl
- succinimidyl acetylthioacetate
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Tagawa ST, Milowsky MI, Morris M, Vallabhajosula S, Christos P, Akhtar NH, Osborne J, Goldsmith SJ, Larson S, Taskar NP, Scher HI, Bander NH, Nanus DM. Phase II study of Lutetium-177-labeled anti-prostate-specific membrane antigen monoclonal antibody J591 for metastatic castration-resistant prostate cancer. Clin Cancer Res 2013; 19:5182-91. [PMID: 23714732 DOI: 10.1158/1078-0432.ccr-13-0231] [Citation(s) in RCA: 306] [Impact Index Per Article: 27.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE To assess the efficacy of a single infusion of radiolabeled anti-prostate-specific membrane antigen (PSMA) monoclonal antibody J591 (lutetium-177; (177)Lu) by prostate-specific antigen (PSA) decline, measurable disease response, and survival. EXPERIMENTAL DESIGN In this dual-center phase II study, two cohorts with progressive metastatic castration-resistant prostate cancer received one dose of (177)Lu-J591 (15 patients at 65 mCi/m(2), 17 at 70 mCi/m(2)) with radionuclide imaging. Expansion cohort (n = 15) received 70 mCi/m(2) to verify response rate and examine biomarkers. RESULTS Forty-seven patients who progressed after hormonal therapies (55.3% also received prior chemotherapy) received (177)Lu-J591. A total of 10.6% experienced ≥50% decline in PSA, 36.2% experienced ≥30% decline, and 59.6% experienced any PSA decline following their single treatment. One of 12 with measurable disease experienced a partial radiographic response (8 with stable disease). Sites of prostate cancer metastases were targeted in 44 of 47 (93.6%) as determined by planar imaging. All experienced reversible hematologic toxicity, with grade 4 thrombocytopenia occurring in 46.8% (29.8% received platelet transfusions) without significant hemorrhage. A total of 25.5% experienced grade 4 neutropenia, with one episode of febrile neutropenia. The phase I maximum tolerated dose (70 mCi/m(2)) resulted in more 30% PSA declines (46.9% vs. 13.3%, P = 0.048) and longer survival (21.8 vs. 11.9 months, P = 0.03), but also more grade 4 hematologic toxicity and platelet transfusions. No serious nonhematologic toxicity occurred. Those with poor PSMA imaging were less likely to respond. CONCLUSION A single dose of (177)Lu-J591 was well tolerated with reversible myelosuppression. Accurate tumor targeting and PSA responses were seen with evidence of dose response. Imaging biomarkers seem promising.
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Affiliation(s)
- Scott T Tagawa
- Authors' Affiliations: Weill Cornell Medical College (WCMC); Weill Cornell Cancer Center; Memorial Sloan-Kettering Cancer Center (MSKCC), New York, New York; and University of North Carolina Chapel Hill, North Carolina
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Poli GL, Bianchi C, Virotta G, Bettini A, Moretti R, Trachsel E, Elia G, Giovannoni L, Neri D, Bruno A. Radretumab radioimmunotherapy in patients with brain metastasis: a 124I-L19SIP dosimetric PET study. Cancer Immunol Res 2013; 1:134-43. [PMID: 24777501 DOI: 10.1158/2326-6066.cir-13-0007] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Radioimmunotherapy (RIT) with (131)I-labeled L19SIP (radretumab; a small immunoprotein format antibody directed against the ED-B domain of fibronectin; ∼ 80 kDa molecular weight) has been investigated in several clinical trials. Here, we describe the use of immuno-PET imaging with iodine-124 ((124)I)-labeled L19SIP to predict doses delivered to tumor lesions and healthy organs by a subsequent radretumab RIT in patients with brain metastases from solid cancer. Bone marrow doses were evaluated both during the diagnostic phase and posttherapy, measuring activities in blood (germanium detector) and whole body (lanthanum bromide detector). Expected doses for radretumab administration (4,107 MBq/m(2)) were calculated from data obtained after administration of an average of 167 MBq (124)I-L19SIP to 6 patients. To assess lesion average doses, the positron emission tomography (PET) scanner was calibrated for the use of (124)I with an International Electrotechnical Commission (IEC) Body Phantom and recovery coefficients were calculated. The average dose to bone red marrow was 0.21 Gy/GBq, with high correlation between provisional and actual posttherapy doses. Although the fraction of injected activity in normal organs was similar in different patients, the antibody uptake in the neoplastic lesions varied by as much as a factor of 60. Immuno-PET with (124)I-labeled L19SIP offers significant advantages over conventional (131)I imaging, in particular accuracy of dosimetric results. Furthermore, the study indicates that antibody uptake can be highly variable even in different lesions of the same patient and that immuno-PET procedures may guide product development with armed antibodies.
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Affiliation(s)
- Gian Luca Poli
- Authors' Affiliations: Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences, ETH Zurich, Zurich, Switzerland
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Carcinoembryonic antigen is the preferred biomarker for in vivo colorectal cancer targeting. Br J Cancer 2013; 108:662-7. [PMID: 23322207 PMCID: PMC3593555 DOI: 10.1038/bjc.2012.605] [Citation(s) in RCA: 112] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Background: Colorectal cancer-specific biomarkers have been used as molecular targets for fluorescent intra-operative imaging, targeted PET/MRI, and selective cytotoxic drug delivery yet the selection of biomarkers used is rarely evidence-based. We evaluated sensitivities and specificites of four of the most commonly used markers: carcinoembryonic antigen (CEA), tumour-associated glycoprotein-72 (TAG-72), folate receptor-α (FRα) and Epithelial growth factor receptor (EGFR). Methods: Marker expression was evaluated semi-quantitatively in matched mucosal and colorectal cancer tissues from 280 patients using immunohistochemistry (scores of 0–15). Matched positive and negative lymph nodes from 18 patients were also examined. Results: Markers were more highly expressed in tumour tissue than in matched normal tissue in 98.8%, 79.0%, 37.1% and 32.8% of cases for CEA, TAG-72, FRα and EGFR, respectively. Carcinoembryonic antigen showed the greatest differential expression, with tumours scoring a mean of 10.8 points higher than normal tissues (95% CI 10.31–11.21, P<0.001). Similarly, CEA showed the greatest differential expression between positive and negative lymph nodes. Receiver operating characteristic analyses showed CEA to have the best sensitivity (93.7%) and specificity (96.1%) for colorectal cancer detection. Conclusion: Carcinoembryonic antigen has the greatest potential to allow highly specific tumour imaging and drug delivery; future translational research should aim to exploit this.
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Knowles SM, Wu AM. Advances in immuno-positron emission tomography: antibodies for molecular imaging in oncology. J Clin Oncol 2012; 30:3884-92. [PMID: 22987087 PMCID: PMC3478579 DOI: 10.1200/jco.2012.42.4887] [Citation(s) in RCA: 142] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2012] [Accepted: 07/20/2012] [Indexed: 01/20/2023] Open
Abstract
Identification of cancer cell-surface biomarkers and advances in antibody engineering have led to a sharp increase in the development of therapeutic antibodies. These same advances have led to a new generation of radiolabeled antibodies and antibody fragments that can be used as cancer-specific imaging agents, allowing quantitative imaging of cell-surface protein expression in vivo. Immuno-positron emission tomography (immunoPET) imaging with intact antibodies has shown success clinically in diagnosing and staging cancer. Engineered antibody fragments, such as diabodies, minibodies, and single-chain Fv (scFv) -Fc, have been successfully employed for immunoPET imaging of cancer cell-surface biomarkers in preclinical models and are poised to bring same-day imaging into clinical development. ImmunoPET can potentially provide a noninvasive approach for obtaining target-specific information useful for titrating doses for radioimmunotherapy, for patient risk stratification and selection of targeted therapies, for evaluating response to therapy, and for predicting adverse effects, thus contributing to the ongoing development of personalized cancer treatment.
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Affiliation(s)
- Scott M. Knowles
- All authors: David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, CA
| | - Anna M. Wu
- All authors: David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, CA
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Schwartz J, Humm JL, Divgi CR, Larson SM, O'Donoghue JA. Bone marrow dosimetry using 124I-PET. J Nucl Med 2012; 53:615-21. [PMID: 22414633 DOI: 10.2967/jnumed.111.096453] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
UNLABELLED Bone marrow is usually dose-limiting for radioimmunotherapy. In this study, we directly estimated red marrow activity concentration and the self-dose component of absorbed radiation dose to red marrow based on PET/CT of 2 different (124)I-labeled antibodies (cG250 and huA33) and compared the results with plasma activity concentration and plasma-based dose estimates. METHODS Two groups of patients injected with (124)I-labeled monoclonal antibodies (11 patients with renal cancer receiving (124)I-cG250 and 5 patients with colorectal cancer receiving (124)I- huA33) were imaged by PET or PET/CT on 2 or 3 occasions after infusion. Regions of interest were drawn over several lumbar vertebrae, and red marrow activity concentration was quantified. Plasma activity concentration was also quantified using multiple patient blood samples. The red marrow-to-plasma activity concentration ratio (RMPR) was calculated at the times of imaging. The self-dose component of the absorbed radiation dose to the red marrow was estimated from the images, from the plasma measurements, and using a combination of both sets of measurements. RESULTS RMPR was observed to increase with time for both groups of patients. Mean (±SD) time-dependent RMPR (RMPR(t)) for the cG250 group increased from 0.13 ± 0.06 immediately after infusion to 0.23 ± 0.09 at approximately 6 d after infusion. For the huA33 group, mean RMPR(t) was 0.10 ± 0.04 immediately after infusion, 0.13 ± 0.05 approximately 2 d after infusion, and 0.20 ± 0.09 approximately 7 d after infusion. Plasma-based estimates of red marrow self-dose tended to be greater than image-based values by, on average, 11% and 47% for cG250 and huA33, respectively, but by as much as -73% to 62% for individual patients. The hybrid method combining RMPR(t) and plasma activity concentration provided a closer match to the image-based dose estimates (average discrepancies, -2% and 18% for cG250 and huA33, respectively). CONCLUSION These results suggest that the assumption of time-independent proportionality between red marrow and plasma activity concentration may be too simplistic. Individualized imaged-based dosimetry is probably required for the optimal therapeutic delivery of radiolabeled antibodies, which does not compromise red marrow and may allow, for some patients, a substantial increase in administered activity and thus tumor dose.
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Affiliation(s)
- Jazmin Schwartz
- Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, NY, USA.
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