1
|
Chomet M, van Dongen GAMS, Vugts DJ. State of the Art in Radiolabeling of Antibodies with Common and Uncommon Radiometals for Preclinical and Clinical Immuno-PET. Bioconjug Chem 2021; 32:1315-1330. [PMID: 33974403 PMCID: PMC8299458 DOI: 10.1021/acs.bioconjchem.1c00136] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
![]()
Inert
and stable radiolabeling of monoclonal antibodies (mAb),
antibody fragments, or antibody mimetics with radiometals is a prerequisite
for immuno-PET. While radiolabeling is preferably fast, mild, efficient,
and reproducible, especially when applied for human use in a current
Good Manufacturing Practice compliant way, it is crucial that the
obtained radioimmunoconjugate is stable and shows preserved immunoreactivity
and in vivo behavior. Radiometals and chelators have
extensively been evaluated to come to the most ideal radiometal–chelator
pair for each type of antibody derivative. Although PET imaging of
antibodies is a relatively recent tool, applications with 89Zr, 64Cu, and 68Ga have greatly increased in
recent years, especially in the clinical setting, while other less
common radionuclides such as 52Mn, 86Y, 66Ga, and 44Sc, but also 18F as in [18F]AlF are emerging promising candidates for the radiolabeling
of antibodies. This review presents a state of the art overview of
the practical aspects of radiolabeling of antibodies, ranging from
fast kinetic affibodies and nanobodies to slow kinetic intact mAbs.
Herein, we focus on the most common approach which consists of first
modification of the antibody with a chelator, and after eventual storage
of the premodified molecule, radiolabeling as a second step. Other
approaches are possible but have been excluded from this review. The
review includes recent and representative examples from the literature
highlighting which radiometal–chelator–antibody combinations
are the most successful for in vivo application.
Collapse
Affiliation(s)
- Marion Chomet
- Amsterdam UMC, Vrije Universiteit Amsterdam, Radiology & Nuclear Medicine, Cancer Center Amsterdam, De Boelelaan 1117, Amsterdam 1081 HV, The Netherlands
| | - Guus A M S van Dongen
- Amsterdam UMC, Vrije Universiteit Amsterdam, Radiology & Nuclear Medicine, Cancer Center Amsterdam, De Boelelaan 1117, Amsterdam 1081 HV, The Netherlands
| | - Danielle J Vugts
- Amsterdam UMC, Vrije Universiteit Amsterdam, Radiology & Nuclear Medicine, Cancer Center Amsterdam, De Boelelaan 1117, Amsterdam 1081 HV, The Netherlands
| |
Collapse
|
2
|
Abstract
Imaging has played a critical role in the management of patients with cancer. Novel therapies are emerging rapidly; however, they are effective only in some patients. With the advent of new targeted therapeutics and immunotherapy, the limitations of conventional imaging methods are becoming more evident. FDG-PET imaging is restricted to the optimal assessment of immune therapies. There is a critical unmet need for pharmacodynamic and prognostic imaging biomarkers. Radiolabeled antibodies or small molecules can allow for specific assessment of targets in expression and concentration. Several such imaging agents have been under preclinical development. Early human studies with radiolabeled monoclonal antibodies or small molecules targeted to the epidermal growth factor receptor pathway have shown potential; targeted imaging of CA19.9 and CA-IX and are being further explored. Immune-directed imaging agents are highly desirable as biomarkers and preliminary studies with radiolabeled antibodies targeting immune mechanisms appear promising. While novel agents are being developed, larger well-designed studies are needed to validate the role of these agents as biomarkers in the clinical management of patients.
Collapse
Affiliation(s)
- Neeta Pandit-Taskar
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY; Weill Cornell Medical College, New York, NY.
| | - Michael A Postow
- Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY
| |
Collapse
|
3
|
Cho N, Ko S, Shokeen M. Preclinical Development of Near-Infrared-Labeled CD38-Targeted Daratumumab for Optical Imaging of CD38 in Multiple Myeloma. Mol Imaging Biol 2020; 23:186-195. [PMID: 32964391 DOI: 10.1007/s11307-020-01542-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 08/12/2020] [Accepted: 09/10/2020] [Indexed: 11/25/2022]
Abstract
PURPOSE Cluster of differentiation 38 (CD38) is a promising therapeutic target in multiple myeloma (MM) patients and has resulted in the development of several CD38 immunotherapies. Current methods to evaluate CD38 expression in the preclinical setting include ex vivo flow cytometry and immunohistochemistry, which can be cumbersome and do not give whole-body information. In vivo imaging technologies such as positron emission tomography rely on decay of radioisotopes, limiting the number of molecular interactions observed at any given time point. Here, we demonstrate the use of near-infrared (NIR) fluorescence imaging for spatiotemporal monitoring of CD38 expression in preclinical MM using the anti-CD38 daratumumab (DARA) conjugated to the NIR fluorophore IRDye800CW (DARA-IRDye800). PROCEDURES Stability studies with human serum and binding assays with human myeloma cells were performed with DARA-IRDye800. Immunocompromised mice with intra- and extramedullary tumors (n = 5/group) were administered with DARA-IRDye800 for in vivo imaging up to 7 days after injection. Ex vivo biodistribution and flow cytometry studies were performed to validate in vivo imaging results. A separate therapy study was performed in mice with intramedullary tumors that were treated and not treated with DARA at a therapeutic dose (n = 7/group). DARA-IRDye800 was administered for subsequent in vivo and ex vivo imaging in both cohorts of mice. RESULTS DARA-IRDye800 maintained stability and had high affinity for CD38 (KD = 3.5 ± 0.05 nM). DARA-IRDye800 demonstrated a 5- and 18-fold increase in contrast in tumor-bearing regions of mice with extra- and intramedullary MM. Finally, mice treated with therapeutic doses of DARA and imaged with DARA-IRDye800 showed an 11-fold decrease in fluorescence intensities in vivo compared with untreated controls. CONCLUSIONS Our studies establish DARA-IRDye800 as a promising contrast agent for preclinical evaluation of CD38 expression and for further investigating myeloma engraftment and kinetics in relation to anti-CD38 therapies.
Collapse
Affiliation(s)
- Nicholas Cho
- Department of Radiology, Washington University School of Medicine, St. Louis, MO, 63110, USA
- Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - Sooah Ko
- Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - Monica Shokeen
- Department of Radiology, Washington University School of Medicine, St. Louis, MO, 63110, USA.
- Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, MO, 63110, USA.
- Alvin J. Siteman Cancer Center, Washington University School of Medicine and Barnes Jewish Hospital, St. Louis, MO, 63110, USA.
| |
Collapse
|
4
|
Wei W, Ni D, Ehlerding EB, Luo QY, Cai W. PET Imaging of Receptor Tyrosine Kinases in Cancer. Mol Cancer Ther 2019; 17:1625-1636. [PMID: 30068751 DOI: 10.1158/1535-7163.mct-18-0087] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Revised: 04/19/2018] [Accepted: 06/04/2018] [Indexed: 12/22/2022]
Abstract
Overexpression and/or mutations of the receptor tyrosine kinase (RTK) subfamilies, such as epidermal growth factor receptors (EGFR) and vascular endothelial growth factor receptors (VEGFR), are closely associated with tumor cell growth, differentiation, proliferation, apoptosis, and cellular invasiveness. Monoclonal antibodies (mAb) and tyrosine kinase inhibitors (TKI) specifically inhibiting these RTKs have shown remarkable success in improving patient survival in many cancer types. However, poor response and even drug resistance inevitably occur. In this setting, the ability to detect and visualize RTKs with noninvasive diagnostic tools will greatly refine clinical treatment strategies for cancer patients, facilitate precise response prediction, and improve drug development. Positron emission tomography (PET) agents using targeted radioactively labeled antibodies have been developed to visualize tumor RTKs and are changing clinical decisions for certain cancer types. In the present review, we primarily focus on PET imaging of RTKs using radiolabeled antibodies with an emphasis on the clinical applications of these immunoPET probes. Mol Cancer Ther; 17(8); 1625-36. ©2018 AACR.
Collapse
Affiliation(s)
- Weijun Wei
- Department of Nuclear Medicine, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China.,Department of Radiology, University of Wisconsin-Madison, Wisconsin
| | - Dalong Ni
- Department of Radiology, University of Wisconsin-Madison, Wisconsin
| | - Emily B Ehlerding
- Department of Medical Physics, University of Wisconsin-Madison, Wisconsin
| | - Quan-Yong Luo
- Department of Nuclear Medicine, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China.
| | - Weibo Cai
- Department of Radiology, University of Wisconsin-Madison, Wisconsin. .,Department of Medical Physics, University of Wisconsin-Madison, Wisconsin.,University of Wisconsin Carbone Cancer Center, Madison, Wisconsin
| |
Collapse
|
5
|
Vija AH, Bartenstein PA, Froelich JW, Kuwert T, Macapinlac H, Daignault CP, Gowda N, Hadjiev O, Hephzibah J, Huang P, Ilhan H, Jessop A, Cachovan M, Ma J, Ding X, Spence D, Platsch G, Szabo Z. ROC study and SUV threshold using quantitative multi-modal SPECT for bone imaging. Eur J Hybrid Imaging 2019; 3:10. [PMID: 34191147 PMCID: PMC8218047 DOI: 10.1186/s41824-019-0057-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Accepted: 05/24/2019] [Indexed: 11/23/2022] Open
Abstract
Background We investigated the clinical performance of a quantitative multi-modal SPECT/CT reconstruction platform for yielding radioactivity concentrations of bone imaging with 99mTc-methylene diphosphonate (MDP) or 99mTc-dicarboxypropane diphosphonate (DPD). The novel reconstruction incorporates CT-derived tissue information while preserving the delineation of tissue boundaries. We assessed image-based reader concordance and confidence, and determined lesion classification and SUV thresholds from ROC analysis. Methods Seventy-two cancer patients were scanned at three US and two German clinical sites, each contributing two experienced board-certified nuclear medicine physicians as readers. We compared four variants of the reconstructed data resulting from the Flash3D (F3D) and the xSPECT Bone™ (xB) iterative reconstruction methods and presented images to the readers with and without a fused CT, resulting in four combinations. We used an all-or-none approach for inclusion, compiling results only when a reader completed all reads in a subset. After the final read, we conducted a “surrogate truth” reading, presenting all data to each reader. For any remaining discordant lesions, we conducted a consensus read. We next undertook ROC analysis to determine SUV thresholds for differentiating benign and lesional uptake. Results On a five-point rating scale of image quality, xB was deemed better by almost two points in resolution and one point better in overall acceptance compared to F3D. The absolute agreement of the rendered decision between the nine readers was significantly higher with CT information either inside the reconstruction (xB, xBCT) or simply through image fusion (F3DCT): 0.70 (xBCT), 0.67 (F3DCT), 0.64 (xB), and 0.46 (F3D). The confidence level to characterize the lesion was significantly higher (3.03x w/o CT, 1.32x w/CT) for xB than for F3D. There was high correlation between xB and F3D scores for lesion detection and classification, but lesion detection confidence was 41% higher w/o CT, and 21% higher w/CT for xB compared to F3D. Without CT, xB had 6.6% higher sensitivity, 7.1% higher specificity, and 6.9% greater AUC compared to F3D, and similarly with CT-fusion. The overall SUV-criterion (SUVc) of xB (12) exceeded that for xSPECT Quant™ (xQ; 9), an approach not using the tissue delineation of xB. SUV critical numbers depended on lesion volume and location. For non-joint lesions > 6 ml, the AUC for xQ and xB was 94%, with SUVc > 9.28 (xQ) or > 9.68 (xB); for non-joint lesions ≤ 6 ml, AUCs were 81% (xQ) and 88% (xB), and SUVc > 8.2 (xQ) or > 9.1 (xB). For joint lesions, the AUC was 80% (xQ) and 83% (xB), with SUVc > 8.61 (xQ) or > 13.4 (xB). Conclusion The incorporation of high-resolution CT-based tissue delineation in SPECT reconstruction (xSPECT Bone) provides better resolution and detects smaller lesions (6 ml), and the CT component facilitates lesion characterization. Our approach increases confidence, concordance, and accuracy for readers with a wide range of experience. The xB method retained high reading accuracy, despite the unfamiliar image presentation, having greatest impact for smaller lesions, and better localization of foci relative to bone anatomy. The quantitative assessment yielded an SUV-threshold for sensitively distinguishing benign and malignant lesions. Ongoing efforts shall establish clinically usable protocols and SUV thresholds for decision-making based on quantitative SPECT.
Collapse
Affiliation(s)
- A H Vija
- Molecular Imaging, Siemens Medical Solutions USA, Inc, Hoffman Estates, IL, USA.
| | | | | | - T Kuwert
- Friedrich Alexander Universität Erlangen, Erlangen, Germany
| | | | - C P Daignault
- University of Minnesota, Minneapolis, MN, USA.,Veterans Medical Center, Minneapolis, MN, USA
| | - N Gowda
- University of Minnesota, Minneapolis, MN, USA.,Consulting Radiology, Edina, MN, USA
| | - O Hadjiev
- University of Minnesota, Minneapolis, MN, USA.,Milwaukee Radiologists, Greenfield, WI, USA
| | - J Hephzibah
- Johns Hopkins University, Baltimore, MD, USA.,Christian Medical College, Vellore, India
| | - P Huang
- Johns Hopkins University, Baltimore, MD, USA
| | - H Ilhan
- Ludwig-Maximilians Universität, München, Munich, Germany
| | - A Jessop
- MD Anderson Cancer Center, Houston, TX, USA.,Vanderbilt University Medical Center, Nashville, TN, USA
| | - M Cachovan
- Siemens Healthineers GmbH, Erlangen, Germany
| | - J Ma
- Molecular Imaging, Siemens Medical Solutions USA, Inc, Hoffman Estates, IL, USA
| | - X Ding
- Molecular Imaging, Siemens Medical Solutions USA, Inc, Hoffman Estates, IL, USA
| | - D Spence
- Molecular Imaging, Siemens Medical Solutions USA, Inc, Hoffman Estates, IL, USA
| | - G Platsch
- Siemens Healthineers GmbH, Erlangen, Germany
| | - Z Szabo
- Johns Hopkins University, Baltimore, MD, USA
| |
Collapse
|
6
|
Fu R, Carroll L, Yahioglu G, Aboagye EO, Miller PW. Antibody Fragment and Affibody ImmunoPET Imaging Agents: Radiolabelling Strategies and Applications. ChemMedChem 2018; 13:2466-2478. [PMID: 30246488 PMCID: PMC6587488 DOI: 10.1002/cmdc.201800624] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Indexed: 12/12/2022]
Abstract
Antibodies have long been recognised as potent vectors for carrying diagnostic medical radionuclides, contrast agents and optical probes to diseased tissue for imaging. The area of ImmunoPET combines the use of positron emission tomography (PET) imaging with antibodies to improve the diagnosis, staging and monitoring of diseases. Recent developments in antibody engineering and PET radiochemistry have led to a new wave of experimental ImmunoPET imaging agents that are based on a range of antibody fragments and affibodies. In contrast to full antibodies, engineered affibody proteins and antibody fragments such as minibodies, diabodies, single-chain variable region fragments (scFvs), and nanobodies are much smaller but retain the essential specificities and affinities of full antibodies in addition to more desirable pharmacokinetics for imaging. Herein, recent key developments in the PET radiolabelling strategies of antibody fragments and related affibody molecules are highlighted, along with the main PET imaging applications of overexpressed antigen-associated tumours and immune cells.
Collapse
Affiliation(s)
- Ruisi Fu
- Department of ChemistryImperial College LondonExhibition RoadSouth Kensington, LondonSW7 2AZUK
- Comprehensive Cancer Imaging Centre, Department of Surgery and CancerImperial College London, Hammersmith CampusDu Cane RoadLondonW12 0NNUK
| | - Laurence Carroll
- Comprehensive Cancer Imaging Centre, Department of Surgery and CancerImperial College London, Hammersmith CampusDu Cane RoadLondonW12 0NNUK
| | - Gokhan Yahioglu
- Department of ChemistryImperial College LondonExhibition RoadSouth Kensington, LondonSW7 2AZUK
- Antikor Biopharma Ltd.StevenageSG1 2FXUK
| | - Eric O. Aboagye
- Comprehensive Cancer Imaging Centre, Department of Surgery and CancerImperial College London, Hammersmith CampusDu Cane RoadLondonW12 0NNUK
| | - Philip W. Miller
- Department of ChemistryImperial College LondonExhibition RoadSouth Kensington, LondonSW7 2AZUK
| |
Collapse
|
7
|
Bao R, Wang Y, Lai J, Zhu H, Zhao Y, Li S, Li N, Huang J, Yang Z, Wang F, Liu Z. Enhancing Anti-PD-1/PD-L1 Immune Checkpoint Inhibitory Cancer Therapy by CD276-Targeted Photodynamic Ablation of Tumor Cells and Tumor Vasculature. Mol Pharm 2018; 16:339-348. [PMID: 30452269 DOI: 10.1021/acs.molpharmaceut.8b00997] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Antiangiogenic therapies have been demonstrated to improve the efficacy of immune checkpoint inhibition by overcoming the immunosuppressive status of the tumor microenvironment. However, most of the current antiangiogenic agents cannot discriminate tumor angiogenesis from physiological angiogenesis. The aim of this study was to investigate whether a photodynamic therapy (PDT) agent that targets CD276, a receptor overexpressed in various tumor cells and tumor vasculature but with limited expression in normal tissue vasculature, could improve the tumor inhibitory efficacy of a PD-1/PD-L1 blockade. A CD276-targeting agent (IRD-αCD276/Fab) was synthesized by conjugating the Fab fragment of an anti-CD276 antibody with a photosensitizer IRDye700. The in vivo tumor-targeting efficacy and therapeutic effects of IRD-αCD276/Fab with or without an anti-PD-1/PD-L1 blockade were tested in subcutaneous and lung metastatic tumor models. PDT using IRD-αCD276/Fab significantly suppressed the growth of subcutaneous 4T1 tumor and inhibited its lung metastasis. Moreover, it triggered in vivo antitumor immunity by increasing the activation and maturation of dendritic cells. Tumor PD-L1 levels were also markedly increased after PDT using IRD-αCD276/Fab, as evidenced by noninvasive PD-L1-targeted small-animal PET imaging. In combination with an anti-PD-1/PD-L1 blockade, IRD-αCD276/Fab PDT markedly suppressed the growth of tumors and prevented their metastasis to the lung by recruiting the tumor infiltration of CD8+ T cells. Our data provide evidence for the role of CD276-targeted PDT for local immune modulation, and its combination with PD-L1/PD-1 axis inhibition is a promising strategy for eliminating primary tumors as well as disseminated metastases, by generating local and systemic antitumor responses.
Collapse
Affiliation(s)
- Rui Bao
- Medical Isotopes Research Center and Department of Radiation Medicine, School of Basic Medical Sciences , Peking University Health Science Center , Beijing 100191 , China
| | - Yanpu Wang
- Medical Isotopes Research Center and Department of Radiation Medicine, School of Basic Medical Sciences , Peking University Health Science Center , Beijing 100191 , China
| | - Jianhao Lai
- Medical Isotopes Research Center and Department of Radiation Medicine, School of Basic Medical Sciences , Peking University Health Science Center , Beijing 100191 , China
| | - Hua Zhu
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Nuclear Medicine , Peking University Cancer Hospital & Institute , Beijing 100142 , China
| | - Yang Zhao
- Medical Isotopes Research Center and Department of Radiation Medicine, School of Basic Medical Sciences , Peking University Health Science Center , Beijing 100191 , China
| | - Suping Li
- CAS Key Laboratory for Biomedical Effects of Nanomaterials & Nanosafety, CAS Center for Excellence in Nanoscience , National Center for Nanoscience and Technology , Beijing 100190 , China
| | - Nan Li
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Nuclear Medicine , Peking University Cancer Hospital & Institute , Beijing 100142 , China
| | - Jing Huang
- Department of Immunology, School of Basic Medical Sciences , Peking University Health Science Center , Beijing 100191 , China
| | - Zhi Yang
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Nuclear Medicine , Peking University Cancer Hospital & Institute , Beijing 100142 , China
| | - Fan Wang
- Medical Isotopes Research Center and Department of Radiation Medicine, School of Basic Medical Sciences , Peking University Health Science Center , Beijing 100191 , China
| | - Zhaofei Liu
- Medical Isotopes Research Center and Department of Radiation Medicine, School of Basic Medical Sciences , Peking University Health Science Center , Beijing 100191 , China
| |
Collapse
|
8
|
Fluorine-18 Labeling of the HER2-Targeting Single-Domain Antibody 2Rs15d Using a Residualizing Label and Preclinical Evaluation. Mol Imaging Biol 2018; 19:867-877. [PMID: 28409338 DOI: 10.1007/s11307-017-1082-x] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
PURPOSE Our previous studies with F-18-labeled anti-HER2 single-domain antibodies (sdAbs) utilized 5F7, which binds to the same epitope on HER2 as trastuzumab, complicating its use for positron emission tomography (PET) imaging of patients undergoing trastuzumab therapy. On the other hand, sdAb 2Rs15d binds to a different epitope on HER2 and thus might be a preferable vector for imaging in these patients. The aim of this study was to evaluate the tumor targeting of F-18 -labeled 2Rs15d in HER2-expressing breast carcinoma cells and xenografts. PROCEDURES sdAb 2Rs15d was labeled with the residualizing labels N-succinimidyl 3-((4-(4-[18F]fluorobutyl)-1H-1,2,3-triazol-1-yl)methyl)-5-(guanidinomethyl)benzoate ([18F]RL-I) and N-succinimidyl 4-guanidinomethyl-3-[125I]iodobenzoate ([125I]SGMIB), and the purity and HER2-specific binding affinity and immunoreactivity were assessed after labeling. The biodistribution of I-125- and F-18-labeled 2Rs15d was determined in SCID mice bearing subcutaneous BT474M1 xenografts. MicroPET/x-ray computed tomograph (CT) imaging of [18F]RL-I-2Rs15d was performed in this model and compared to that of nonspecific sdAb [18F]RL-I-R3B23. MicroPET/CT imaging was also done in an intracranial HER2-positive breast cancer brain metastasis model after administration of 2Rs15d-, 5F7-, and R3B23-[18F]RL-I conjugates. RESULTS [18F]RL-I was conjugated to 2Rs15d in 40.8 ± 9.1 % yield and with a radiochemical purity of 97-100 %. Its immunoreactive fraction (IRF) and affinity for HER2-specific binding were 79.2 ± 5.4 % and 7.1 ± 0.4 nM, respectively. [125I]SGMIB was conjugated to 2Rs15d in 58.4 ± 8.2 % yield and with a radiochemical purity of 95-99 %; its IRF and affinity for HER2-specific binding were 79.0 ± 12.9 % and 4.5 ± 0.8 nM, respectively. Internalized radioactivity in BT474M1 cells in vitro for [18F]RL-I-2Rs15d was 43.7 ± 3.6, 36.5 ± 2.6, and 21.7 ± 1.2 % of initially bound radioactivity at 1, 2, and 4 h, respectively, and was similar to that seen for [125I]SGMIB-2Rs15d. Uptake of [18F]RL-I-2Rs15d in subcutaneous xenografts was 16-20 %ID/g over 1-3 h. Subcutaneous tumor could be clearly delineated by microPET/CT imaging with [18F]RL-I-2Rs15d but not with [18F]RL-I-R3B23. Intracranial breast cancer brain metastases could be visualized after intravenous administration of both [18F]RL-I-2Rs15d and [18F]RL-I-5F7. CONCLUSIONS Although radiolabeled 2Rs15d conjugates exhibited lower tumor cell retention both in vitro and in vivo than that observed previously for 5F7, given that it binds to a different epitope on HER2 from those targeted by the clinically utilized HER2-targeted therapeutic antibodies trastuzumab and pertuzumab, F-18-labeled 2Rs15d has potential for assessing HER2 status by PET imaging after trastuzumab and/or pertuzumab therapy.
Collapse
|
9
|
Lai J, Lu D, Zhang C, Zhu H, Gao L, Wang Y, Bao R, Zhao Y, Jia B, Wang F, Yang Z, Liu Z. Noninvasive small-animal imaging of galectin-1 upregulation for predicting tumor resistance to radiotherapy. Biomaterials 2018; 158:1-9. [DOI: 10.1016/j.biomaterials.2017.12.012] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Revised: 12/13/2017] [Accepted: 12/14/2017] [Indexed: 12/19/2022]
|
10
|
Enhanced Antitumor Effects of Epidermal Growth Factor Receptor Targetable Cetuximab-Conjugated Polymeric Micelles for Photodynamic Therapy. NANOMATERIALS 2018; 8:nano8020121. [PMID: 29470420 PMCID: PMC5853752 DOI: 10.3390/nano8020121] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Revised: 12/30/2017] [Accepted: 01/18/2018] [Indexed: 12/21/2022]
Abstract
Nanocarrier-based delivery systems are promising strategies for enhanced therapeutic efficacy and safety of toxic drugs. Photodynamic therapy (PDT)—a light-triggered chemical reaction that generates localized tissue damage for disease treatments—usually has side effects, and thus patients receiving photosensitizers should be kept away from direct light to avoid skin phototoxicity. In this study, a clinically therapeutic antibody cetuximab (C225) was conjugated to the surface of methoxy poly(ethylene glycol)-b-poly(lactide) (mPEG-b-PLA) micelles via thiol-maleimide coupling to allow tumor-targetable chlorin e6 (Ce6) delivery. Our results demonstrate that more C225-conjugated Ce6-loaded polymeric micelles (C225-Ce6/PM) were selectively taken up than Ce6/PM or IgG conjugated Ce6/PM by epidermal growth factor receptor (EGFR)-overexpressing A431 cells observed by confocal laser scanning microscopy (CLSM), thereby decreasing the IC50 value of Ce6-mediated PDT from 0.42 to 0.173 μM. No significant differences were observed in cellular uptake study or IC50 value between C225-Ce6/PM and Ce6/PM groups in lower EGFR expression HT-29 cells. For antitumor study, the tumor volumes in the C225-Ce6/PM-PDT group (percentage of tumor growth inhibition, TGI% = 84.8) were significantly smaller than those in the Ce6-PDT (TGI% = 38.4) and Ce6/PM-PDT groups (TGI% = 53.3) (p < 0.05) at day 21 through reduced cell proliferation in A431 xenografted mice. These results indicated that active EGFR targeting of photosensitizer-loaded micelles provides a possible way to resolve the dose-limiting toxicity of conventional photosensitizers and represents a potential delivery system for PDT in a clinical setting.
Collapse
|
11
|
Liu F, Liu T, Xu X, Guo X, Li N, Xiong C, Li C, Zhu H, Yang Z. Design, Synthesis, and Biological Evaluation of 68Ga-DOTA-PA1 for Lung Cancer: A Novel PET Tracer for Multiple Somatostatin Receptor Imaging. Mol Pharm 2018; 15:619-628. [PMID: 29278911 DOI: 10.1021/acs.molpharmaceut.7b00963] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Most of the radiolabeled somatostatin analogues (SSAs) are specific for subtype somatostatin receptor 2 (SSTR2). Lack of ligands targeting other subtypes of SSTRs, especially SSTR1, SSTR3, and SSTR5, limited their applications in tumors of low SSTR2 expression, including lung tumor. In this study, we aimed to design and synthesize a positron emission tomography (PET) radiotracer targeting multi-subtypes of SSTRs for PET imaging. PA1 peptide and its conjugate with 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) chelator or fluorescein isothiocyanate (FITC) at the N-terminal of the lysine position were synthesized. 68Ga was chelated to DOTA-PA1 to obtain 68Ga-DOTA-PA1 radiotracer. The stability, lipophilicity, binding affinity, and binding specificity of 68Ga-DOTA-PA1 and FITC-PA1 were evaluated by various in vitro experiments. Micro-PET imaging of 68Ga-DOTA-PA1 was performed in nude mice bearing A549 lung adenocarcinoma, as compared with 68Ga-DOTA-(Tyr3)-octreotate (68Ga-DOTA-TATE). Histological analysis of SSTR expression in A549 tumor tissues and human tumor tissues was conducted using immunofluorescence staining and immunohistochemical assay. 68Ga-DOTA-PA1 had high radiochemical yield and radiochemical purity of over 95% and 99%, respectively. The radiotracer was stable in vitro in different buffers over a 2 h incubation period. Cell uptake of 68Ga-DOTA-PA1 was 1.31-, 1.33-, and 1.90-fold that of 68Ga-DOTA-TATE, which has high binding affinity only for SSTR2, after 2 h incubation in H520, PG, and A549 lung cancer cell lines, respectively. Micro-PET images of 68Ga-DOTA-PA1 showed that the PET imaging signal correlated with the total expression of SSTRs, instead of SSTR2 only, which was measured by Western blotting and immunofluorescence analysis in mice bearing A549 tumors. In summary, a novel PET radiotracer, 68Ga-DOTA-PA1, targeting multi-subtypes of SSTRs, was successfully synthesized and was confirmed to be useful for PET imaging. It may have potential as a noninvasive PET radiotracer for imaging SSTR-positive tumors.
Collapse
Affiliation(s)
- Fei Liu
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Nuclear Medicine, Peking University Cancer Hospital & Institute , Beijing 100142, P. R. China
| | - Teli Liu
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Nuclear Medicine, Peking University Cancer Hospital & Institute , Beijing 100142, P. R. China
| | - Xiaoxia Xu
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Nuclear Medicine, Peking University Cancer Hospital & Institute , Beijing 100142, P. R. China
| | - Xiaoyi Guo
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Nuclear Medicine, Peking University Cancer Hospital & Institute , Beijing 100142, P. R. China
| | - Nan Li
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Nuclear Medicine, Peking University Cancer Hospital & Institute , Beijing 100142, P. R. China
| | - Chiyi Xiong
- Department of Cancer Systems Imaging, The University of Texas MD Anderson Cancer Center , Houston, Texas 77030, United States
| | - Chun Li
- Department of Cancer Systems Imaging, The University of Texas MD Anderson Cancer Center , Houston, Texas 77030, United States
| | - Hua Zhu
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Nuclear Medicine, Peking University Cancer Hospital & Institute , Beijing 100142, P. R. China
| | - Zhi Yang
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Nuclear Medicine, Peking University Cancer Hospital & Institute , Beijing 100142, P. R. China
| |
Collapse
|
12
|
Freise AC, Wu AM. In vivo imaging with antibodies and engineered fragments. Mol Immunol 2015; 67:142-52. [PMID: 25934435 PMCID: PMC4529772 DOI: 10.1016/j.molimm.2015.04.001] [Citation(s) in RCA: 153] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2015] [Revised: 03/31/2015] [Accepted: 04/02/2015] [Indexed: 12/20/2022]
Abstract
Antibodies have clearly demonstrated their utility as therapeutics, providing highly selective and effective drugs to treat diseases in oncology, hematology, cardiology, immunology and autoimmunity, and infectious diseases. More recently, a pressing need for equally specific and targeted imaging agents for assessing disease in vivo, in preclinical models and patients, has emerged. This review summarizes strategies for developing and optimizing antibodies as targeted probes for use in non-invasive imaging using radioactive, optical, magnetic resonance, and ultrasound approaches. Recent advances in engineered antibody fragments and scaffolds, conjugation and labeling methods, and multimodality probes are highlighted. Importantly, antibody-based imaging probes are seeing new applications in detection and quantitation of cell surface biomarkers, imaging specific responses to targeted therapies, and monitoring immune responses in oncology and other diseases. Antibody-based imaging will provide essential tools to facilitate the transition to truly precision medicine.
Collapse
Affiliation(s)
- Amanda C Freise
- Crump Institute for Molecular Imaging, Department of Molecular and Medical Pharmacology, David Geffen School of Medicine at UCLA, USA
| | - Anna M Wu
- Crump Institute for Molecular Imaging, Department of Molecular and Medical Pharmacology, David Geffen School of Medicine at UCLA, USA.
| |
Collapse
|
13
|
Gao L, Liu H, Sun X, Gao D, Zhang C, Jia B, Zhu Z, Wang F, Liu Z. Molecular Imaging of Post-Src Inhibition Tumor Signatures for Guiding Dasatinib Combination Therapy. J Nucl Med 2015; 57:321-6. [PMID: 26383149 DOI: 10.2967/jnumed.115.158881] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2015] [Accepted: 08/26/2015] [Indexed: 01/27/2023] Open
Abstract
UNLABELLED Noninvasive, real-time, quantitative measurement of key biomarkers associated with cancer therapeutic interventions could provide a better understanding of cancer biology. We investigated in this study whether incorporating multiple molecular imaging approaches could be used to guide dasatinib anti-Src therapy and aid in the rational design of a combination therapy regimen. METHODS Bioluminescence imaging, (18)F-FDG PET, integrin αvβ3-targeted SPECT/CT, and vascular endothelial growth factor-targeted near-infrared fluorescence imaging were performed before and after dasatinib treatment in a tumor mouse model. RESULTS There was no significant difference in the bioluminescence imaging signal or (18)F-FDG tumor uptake in dasatinib-treated tumors compared with the control tumors. However, the uptake of (99m)T-3PRGD2 (integrin αvβ3-specific) and DyLight755-ranibizumab (vascular endothelial growth factor-specific) in the dasatinib-treated tumors was significantly lower than that in the control tumors. In vitro studies confirmed the antiangiogenic effects of dasatinib but indicated a lack of cytotoxicity. Dasatinib plus cytotoxic docetaxel elicited marked synergistic tumor growth inhibition in vivo. CONCLUSION Visualization of post-Src inhibition tumor signatures through multiple imaging approaches facilitates sensitive and quantitative measurement of cancer biomarkers in vivo, thus aiding in the rational design of dasatinib combination therapy.
Collapse
Affiliation(s)
- Liquan Gao
- Medical Isotopes Research Center and Department of Radiation Medicine, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China
| | - Hao Liu
- Medical Isotopes Research Center and Department of Radiation Medicine, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China
| | - Xianlei Sun
- Medical Isotopes Research Center and Department of Radiation Medicine, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China
| | - Duo Gao
- Medical Isotopes Research Center and Department of Radiation Medicine, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China
| | - Chenran Zhang
- Medical Isotopes Research Center and Department of Radiation Medicine, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China
| | - Bing Jia
- Medical Isotopes Research Center and Department of Radiation Medicine, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China
| | - Zhaohui Zhu
- Department of Nuclear Medicine, Peking Union Medical College Hospital, Beijing, China; and
| | - Fan Wang
- Medical Isotopes Research Center and Department of Radiation Medicine, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China Interdisciplinary Laboratory, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Zhaofei Liu
- Medical Isotopes Research Center and Department of Radiation Medicine, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China
| |
Collapse
|
14
|
Sun X, Gao D, Gao L, Zhang C, Yu X, Jia B, Wang F, Liu Z. Molecular imaging of tumor-infiltrating macrophages in a preclinical mouse model of breast cancer. Theranostics 2015; 5:597-608. [PMID: 25825599 PMCID: PMC4377728 DOI: 10.7150/thno.11546] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Accepted: 02/05/2015] [Indexed: 01/16/2023] Open
Abstract
Significant evidence has indicated that tumor-associated macrophages (TAMs) play a critical role in the proliferation, invasion, angiogenesis, and metastasis of a variety of human carcinomas. In this study, we investigated whether near-infrared fluorescence (NIRF) imaging using a macrophage mannose receptor (MMR; CD206)-targeting agent could be used to noninvasively visualize and quantify changes in TAMs in vivo. The CD206-targeting NIRF agent, Dye-anti-CD206, was prepared and characterized in vitro and in vivo. By using NIRF imaging, we were able to noninvasively image tumor-infiltrating macrophages in the 4T1 mouse breast cancer model. Importantly, longitudinal NIRF imaging revealed the depletion of macrophages in response to zoledronic acid (ZA) treatment. However, ZA alone did not lead to the inhibition of 4T1 tumor growth. We therefore combined anti-macrophage ZA therapy and tumor cytotoxic docetaxel (DTX) therapy in the mouse model. The results demonstrated that this combination strategy could significantly inhibit tumor growth as well as tumor metastasis to the lungs. Based on these findings, we concluded that CD206-targeted molecular imaging can sensitively detect the dynamic changes in tumor-infiltrating macrophages, and that the combination of macrophage depletion and cytotoxic therapy is a promising strategy for the effective treatment of solid tumors.
Collapse
|
15
|
Sham JG, Kievit FM, Grierson JR, Chiarelli PA, Miyaoka RS, Zhang M, Yeung RS, Minoshima S, Park JO. Glypican-3-targeting F(ab')2 for 89Zr PET of hepatocellular carcinoma. J Nucl Med 2014; 55:2032-7. [PMID: 25359880 PMCID: PMC4259878 DOI: 10.2967/jnumed.114.145102] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
UNLABELLED Hepatocellular carcinoma (HCC) is an increasingly lethal malignancy for which management is critically dependent on accurate imaging. Glypican-3 (GPC3) is a cell surface receptor overexpressed in most HCCs and provides a unique target for molecular diagnostics. The use of monoclonal antibodies (mAbs) that target GPC3 (αGPC3) in PET imaging has shown promise but comes with inherent limitations associated with mAbs such as long circulation times. This study used (89)Zr-conjugated F(ab')2 fragments directed against GPC3 ((89)Zr-αGPC3-F(ab')2) to evaluate the feasibility of the fragments as a diagnostic immuno-PET imaging probe. METHODS Immobilized ficin was used to digest αGPC3, creating αGPC3-F(ab')2 fragments subsequently conjugated to (89)Zr. In vivo biodistribution and PET studies were performed on GPC3-expressing HepG2 and GPC3-nonexpressing RH7777 orthotopic xenografts. RESULTS Reliable αGPC3-F(ab')2 production via immobilized ficin digestion was verified by high-performance liquid chromatography and sodium dodecyl sulfate polyacrylamide gel electrophoresis. (89)Zr-αGPC3-F(ab')2 demonstrated F(ab')2-dependent, antigen-specific cell binding. HepG2 tumor uptake was higher than any other tissue, peaking at 100 ± 21 percentage injected dose per gram (%ID/g) 24 h after injection, a value 33- to 38-fold higher than GPC3-nonexpressing RH7777 tumors. The blood half-life of the (89)Zr-αGPC3-F(ab')2 conjugate was approximately 11 h, compared with approximately 115 h for historic mAb controls. This shorter half-life enabled clear tumor visualization on PET 4 h after administration, with a resultant peak tumor-to-liver contrast ratio of 23.3. Blocking antigen-expressing tumors with an excess of nonradiolabeled αGPC3 resulted in decreased tumor uptake similar to native liver. The kidneys exhibited high tissue uptake, peaking at 24 h with 83 ± 12 %ID/g. HepG2 tumors ranging from 1.5 to 7 mm were clearly visible on PET, whereas larger RH7777 tumors displayed signal lower than background liver tissue. CONCLUSION This study demonstrates the feasibility of using (89)Zr-αGPC3-F(ab')2 for intrahepatic tumor localization with small-animal PET. Faster blood clearance and lower background liver uptake enable excellent signal-to-noise ratios at early time points. Increased renal uptake is similar to that as has been seen with clinical radioactive peptide imaging. (89)Zr-αGPC3-F(ab')2 addresses some of the shortcomings of whole-antibody immuno-PET probes. Further optimization is warranted to maximize probe sensitivity and specificity in the process of clinical translation.
Collapse
Affiliation(s)
- Jonathan G Sham
- Department of Surgery, University of Washington, Seattle, Washington
| | - Forrest M Kievit
- Department of Neurological Surgery, University of Washington, Seattle, Washington
| | - John R Grierson
- Department of Radiology, University of Washington, Seattle, Washington; and
| | - Peter A Chiarelli
- Department of Neurological Surgery, University of Washington, Seattle, Washington
| | - Robert S Miyaoka
- Department of Radiology, University of Washington, Seattle, Washington; and
| | - Miqin Zhang
- Department of Materials Science & Engineering, University of Washington, Seattle, Washington
| | - Raymond S Yeung
- Department of Surgery, University of Washington, Seattle, Washington
| | - Satoshi Minoshima
- Department of Radiology, University of Washington, Seattle, Washington; and
| | - James O Park
- Department of Surgery, University of Washington, Seattle, Washington
| |
Collapse
|