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Chakraborty S, Chatterjee S, Chakravarty R, Sarma HD, Nanabala R, Goswami D, Joy A, Pillai MRA. Synthesis, Quality Control, and Bench-to-Bed Translation of a New [ 68Ga]Ga-Labeled NOTA-Conjugated Bisphosphonate for Imaging Skeletal Metastases by Positron Emission Tomography. Cancer Biother Radiopharm 2024; 39:92-101. [PMID: 38335449 DOI: 10.1089/cbr.2023.0077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2024] Open
Abstract
Background: Early detection of skeletal metastasis is of great interest to determine the prognosis of cancer. Positron emission tomography-computed tomography (PET-CT) imaging provides a better temporal and spectral resolution than single photon emission computed tomography-computed tomography (SPECT-CT) imaging, and hence is more suitable to detect small metastatic lesions. Although [18F]NaF has been approved by U.S. FDA for a similar purpose, requirement of a medical cyclotron for its regular formulation restricts its extensive utilization. Efforts have been made to find suitable alternative molecules that can be labeled with 68Ga and used in PET-CT imaging. Objective: The main objective of this study is to synthesize and evaluate a new [68Ga]Ga-labeled NOTA-conjugated geminal bisphosphonate for its potential use in early detection of skeletal metastases using PET-CT. Methods: The authors performed a multistep synthesis of a new NOTA-conjugated bisphosphonic acid using thiourea linker and radiolabeled the molecule with 68Ga. The radiolabeled formulation was evaluated for its in vitro stability, affinity for hydroxyapatite (HA) particles, preclinical biodistribution in animal models, and PET-CT imaging in patients. Results: The bifunctional chelator (NOTA)-conjugated bisphosphonate was synthesized with 97.8% purity and radiolabeled with 68Ga in high yield (>98%). The radiolabeled formulation was found to retain its stability in vitro to the extent of >95% up to 4 h in physiological saline and human serum. The formulation also showed high affinity for HA particles in vitro with Kd = 907 ± 14 mL/g. Preclinical biodistribution studies in normal Wistar rats demonstrated rapid and almost exclusive skeletal accumulation of the complex. PET-CT imaging in a patient confirmed its ability to detect small metastatic skeletal lesions. Conclusions: The newly synthesized [68Ga]Ga-labeled NOTA-conjugated bisphosphonate is a promising radiotracer for PET-CT imaging for skeletal metastases.
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Affiliation(s)
- Sudipta Chakraborty
- Radiopharmaceuticals Division, Bhabha Atomic Research Centre (BARC), Mumbai, India
- Homi Bhabha National Institute (HBNI), Mumbai, India
| | - Sucheta Chatterjee
- Homi Bhabha National Institute (HBNI), Mumbai, India
- Bio Organic Division, Bhabha Atomic Research Centre (BARC), Mumbai, India
| | - Rubel Chakravarty
- Radiopharmaceuticals Division, Bhabha Atomic Research Centre (BARC), Mumbai, India
- Homi Bhabha National Institute (HBNI), Mumbai, India
| | - Haldhar D Sarma
- Radiation Biology and Health Sciences Division, Bhabha Atomic Research Centre (BARC), Mumbai, India
| | | | - Dibakar Goswami
- Homi Bhabha National Institute (HBNI), Mumbai, India
- Bio Organic Division, Bhabha Atomic Research Centre (BARC), Mumbai, India
| | - Ajith Joy
- Molecular Group of Companies, Ernakulam, India
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Lee I, Kim MH, Lee K, Oh K, Lim H, Ahn JH, Lee YJ, Cheon GJ, Chi DY, Lim SM. Comparison of the Effects of DOTA and NOTA Chelators on 64Cu-Cudotadipep and 64Cu-Cunotadipep for Prostate Cancer. Diagnostics (Basel) 2023; 13:2649. [PMID: 37627908 PMCID: PMC10453766 DOI: 10.3390/diagnostics13162649] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Revised: 07/31/2023] [Accepted: 07/31/2023] [Indexed: 08/27/2023] Open
Abstract
BACKGROUND This study compared the effects of 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) and 1,4,7-triazacyclononane-1,4,7-triacetic acid (NOTA) as 64Cu-chelating agents in newly developed prostate-specific membrane antigen (PSMA) target compounds, 64Cu-cudotadipep and 64Cu-cunotadipep, on pharmacokinetics. METHODS The in vitro stability of the chelators was evaluated using human and mouse serum. In vitro PSMA-binding affinity and cell uptake were compared using human 22Rv1 cells. To evaluate specific PSMA-expressing tumor-targeting efficiency, micro-positron emission tomography (mcroPET)/computed tomography (CT) and biodistribution analysis were performed using PSMA+ PC3-PIP and PSMA- PC3-flu tumor xenografts. RESULTS The serum stability of DOTA- or NOTA-conjugated 64Cu-cudotadipep and 64Cu-cunotadipep was >97%. The Ki value of the NOTA derivative, cunotadipep, in the in vitro affinity binding analysis was higher (2.17 ± 0.25 nM) than that of the DOTA derivative, cudotadipep (6.75 ± 0.42 nM). The cunotadipep exhibited a higher cellular uptake (6.02 ± 0.05%/1 × 106 cells) compared with the cudotadipep (2.93 ± 0.06%/1 × 106 cells). In the biodistribution analysis and microPET/CT imaging, the 64Cu-labeled NOTA derivative, 64Cu-cunotadipep, demonstrated a greater tumor uptake and lower liver uptake than the DOTA derivative. CONCLUSIONS This study indicates that the PSMA-targeted 64Cu-cunotadipep can be applied in clinical practice owing to its high diagnostic power for prostate cancer.
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Affiliation(s)
- Inki Lee
- Department of Nuclear Medicine, Korea Institute of Radiological & Medical Sciences, Seoul 01812, Republic of Korea;
| | - Min Hwan Kim
- Research Institute of Radiopharmaceuticals, FutureChem Co., Ltd., Seoul 04793, Republic of Korea; (M.H.K.); (K.L.); (K.O.); (H.L.)
| | - Kyongkyu Lee
- Research Institute of Radiopharmaceuticals, FutureChem Co., Ltd., Seoul 04793, Republic of Korea; (M.H.K.); (K.L.); (K.O.); (H.L.)
| | - Keumrok Oh
- Research Institute of Radiopharmaceuticals, FutureChem Co., Ltd., Seoul 04793, Republic of Korea; (M.H.K.); (K.L.); (K.O.); (H.L.)
| | - Hyunwoo Lim
- Research Institute of Radiopharmaceuticals, FutureChem Co., Ltd., Seoul 04793, Republic of Korea; (M.H.K.); (K.L.); (K.O.); (H.L.)
| | - Jae Hun Ahn
- Division of Applied RI, Korea Institute of Radiological & Medical Sciences, Seoul 01812, Republic of Korea; (J.H.A.); (Y.J.L.)
- Graduate School of Translational Medicine, Seoul National University College of Medicine, Seoul 03080, Republic of Korea
| | - Yong Jin Lee
- Division of Applied RI, Korea Institute of Radiological & Medical Sciences, Seoul 01812, Republic of Korea; (J.H.A.); (Y.J.L.)
| | - Gi Jeong Cheon
- Department of Nuclear Medicine, Seoul National University College of Medicine, Seoul 03080, Republic of Korea;
| | - Dae Yoon Chi
- Research Institute of Radiopharmaceuticals, FutureChem Co., Ltd., Seoul 04793, Republic of Korea; (M.H.K.); (K.L.); (K.O.); (H.L.)
| | - Sang Moo Lim
- Department of Nuclear Medicine, Korea Institute of Radiological & Medical Sciences, Seoul 01812, Republic of Korea;
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Omolabi KF, Reddy N, Mdanda S, Ntshangase S, Singh SD, Kruger HG, Naicker T, Govender T, Bajinath S. The in vitro and in vivo potential of metal-chelating agents as metallo-beta-lactamase inhibitors against carbapenem-resistant Enterobacterales. FEMS Microbiol Lett 2023; 370:6912242. [PMID: 36521842 DOI: 10.1093/femsle/fnac122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Revised: 11/28/2022] [Accepted: 12/14/2022] [Indexed: 12/23/2022] Open
Abstract
The recent surge in beta-lactamase resistance has created superbugs, which pose a current and significant threat to public healthcare. This has created an urgent need to keep pace with the discovery of inhibitors that can inactivate these beta-lactamase producers. In this study, the in vitro and in vivo activity of 1,4,7-triazacyclononane-1,4,7 triacetic acid (NOTA)-a potential metallo-beta-lactamase (MBL) inhibitor was evaluated in combination with meropenem against MBL producing bacteria. Time-kill studies showed that NOTA restored the efficacy of meropenem against all bacterial strains tested. A murine infection model was then used to study the in vivo pharmacokinetics and efficacy of this metal chelator. The coadministration of NOTA and meropenem (100 mg/kg.bw each) resulted in a significant decrease in the colony-forming units of Klebsiella pneumoniae NDM-1 over an 8-h treatment period (>3 log10 units). The findings suggest that chelators, such as NOTA, hold strong potential for use as a MBL inhibitor in treating carbapenem-resistant Enterobacterale infections.
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Affiliation(s)
- Kehinde F Omolabi
- Catalysis and Peptide Research Unit, University of KwaZulu-Natal, Private Bag X54001,Durban 4000, South Africa
| | - Nakita Reddy
- Catalysis and Peptide Research Unit, University of KwaZulu-Natal, Private Bag X54001,Durban 4000, South Africa
| | - Sipho Mdanda
- Catalysis and Peptide Research Unit, University of KwaZulu-Natal, Private Bag X54001,Durban 4000, South Africa
| | - Sphamandla Ntshangase
- Catalysis and Peptide Research Unit, University of KwaZulu-Natal, Private Bag X54001,Durban 4000, South Africa
| | - Sanil D Singh
- Department of Pharmaceutical Sciences, University of KwaZulu-Natal, Westville Campus, Durban, 4000, South Africa
| | - Hendrik G Kruger
- Catalysis and Peptide Research Unit, University of KwaZulu-Natal, Private Bag X54001,Durban 4000, South Africa
| | - Tricia Naicker
- Catalysis and Peptide Research Unit, University of KwaZulu-Natal, Private Bag X54001,Durban 4000, South Africa
| | - Thavendran Govender
- Department of Chemistry, University of Zululand, Private Bag X1001, KwaDlangezwa 3886, South Africa
| | - Sooraj Bajinath
- Catalysis and Peptide Research Unit, University of KwaZulu-Natal, Private Bag X54001,Durban 4000, South Africa.,Department of Pharmaceutical Sciences, University of KwaZulu-Natal, Westville Campus, Durban, 4000, South Africa.,School of Physiology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg 2193, South Africa
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Petroni D, Riccardi C, Cavasso D, Russo Krauss I, Paduano L, Montesarchio D, Menichetti L. Synthesis and Characterization of Multifunctional Nanovesicles Composed of POPC Lipid Molecules for Nuclear Imaging. Molecules 2021; 26:6591. [PMID: 34770999 DOI: 10.3390/molecules26216591] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 10/26/2021] [Accepted: 10/27/2021] [Indexed: 12/02/2022] Open
Abstract
The integration of nuclear imaging analysis with nanomedicine has tremendously grown and represents a valid and powerful tool for the development and clinical translation of drug delivery systems. Among the various types of nanostructures used as drug carriers, nanovesicles represent intriguing platforms due to their capability to entrap both lipophilic and hydrophilic agents, and their well-known biocompatibility and biodegradability. In this respect, here we present the development of a labelling procedure of POPC (1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine)-based liposomes incorporating an ad hoc designed lipophilic NOTA (1,4,7-triazacyclononane-1,4,7-triacetic acid) analogue, derivatized with an oleic acid residue, able to bind the positron emitter gallium-68(III). Based on POPC features, the optimal conditions for liposome labelling were studied with the aim of optimizing the Ga(III) incorporation and obtaining a significant radiochemical yield. The data presented in this work demonstrate the feasibility of the labelling procedure on POPC liposomes co-formulated with the ad hoc designed NOTA analogue. We thus provided a critical insight into the practical aspects of the development of vesicles for theranostic approaches, which in principle can be extended to other nanosystems exploiting a variety of bioconjugation protocols.
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Baun C, Mitran B, Rinne SS, Dam JH, Olsen BB, Tolmachev V, Orlova A, Thisgaard H. Preclinical Evaluation of the Copper-64 Labeled GRPR-Antagonist RM26 in Comparison with the Cobalt-55 Labeled Counterpart for PET-Imaging of Prostate Cancer. Molecules 2020; 25:E5993. [PMID: 33352838 DOI: 10.3390/molecules25245993] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 12/15/2020] [Accepted: 12/15/2020] [Indexed: 01/21/2023] Open
Abstract
Gastrin-releasing peptide receptor (GRPR) is overexpressed in the majority of prostate cancers. This study aimed to investigate the potential of 64Cu (radionuclide for late time-point PET-imaging) for imaging of GRPR expression using NOTA-PEG2-RM26 and NODAGA-PEG2-RM26. Methods: NOTA/NODAGA-PEG2-RM26 were labeled with 64Cu and evaluated in GRPR-expressing PC-3 cells. Biodistribution of [64Cu]Cu-NOTA/NODAGA-PEG2-RM26 was studied in PC-3 xenografted mice and compared to the biodistribution of [57Co]Co-NOTA/NODAGA-PEG2-RM26 at 3 and 24 h p.i. Preclinical PET/CT imaging was performed in tumor-bearing mice. NOTA/NODAGA-PEG2-RM26 were stably labeled with 64Cu with quantitative yields. In vitro, binding of [64Cu]Cu-NOTA/NODAGA-PEG2-RM26 was rapid and GRPR-specific with slow internalization. In vivo, [64Cu]Cu-NOTA/NODAGA-PEG2-RM26 bound specifically to GRPR-expressing tumors with fast clearance from blood and normal organs and displayed generally comparable biodistribution profiles to [57Co]Co-NOTA/NODAGA-PEG2-RM26; tumor uptake exceeded normal tissue uptake 3 h p.i.. Tumor-to-organ ratios did not increase significantly with time. [64Cu]Cu-NOTA-PEG2-RM26 had a significantly higher liver and pancreas uptake compared to other agents. 57Co-labeled radioconjugates showed overall higher tumor-to-non-tumor ratios, compared to the 64Cu-labeled counterparts. [64Cu]Cu-NOTA/NODAGA-PEG2-RM26 was able to visualize GRPR-expression in a murine PC model using PET. However, [55/57Co]Co-NOTA/NODAGA-PEG2-RM26 provided better in vivo stability and overall higher tumor-to-non-tumor ratios compared with the 64Cu-labeled conjugates.
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Da Pieve C, Makarem A, Turnock S, Maczynska J, Smith G, Kramer-Marek G. Thiol-Reactive PODS-Bearing Bifunctional Chelators for the Development of EGFR-Targeting [ 18F]AlF-Affibody Conjugates. Molecules 2020; 25:E1562. [PMID: 32235296 DOI: 10.3390/molecules25071562] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Revised: 03/26/2020] [Accepted: 03/27/2020] [Indexed: 01/18/2023] Open
Abstract
Site-selective bioconjugation of cysteine-containing peptides and proteins is currently achieved via a maleimide–thiol reaction (Michael addition). When maleimide-functionalized chelators are used and the resulting bioconjugates are subsequently radiolabeled, instability has been observed both during radiosynthesis and post-injection in vivo, reducing radiochemical yield and negatively impacting performance. Recently, a phenyloxadiazolyl methylsulfone derivative (PODS) was proposed as an alternative to maleimide for the site-selective conjugation and radiolabeling of proteins, demonstrating improved in vitro stability and in vivo performance. Therefore, we have synthesized two novel PODS-bearing bifunctional chelators (NOTA-PODS and NODAGA-PODS) and attached them to the EGFR-targeting affibody molecule ZEGFR:03115. After radiolabeling with the aluminum fluoride complex ([18F]AlF), both conjugates showed good stability in murine serum. When injected in high EGFR-expressing tumor-bearing mice, [18F]AlF-NOTA-PODS-ZEGFR:03115 and [18F]AlF-NODAGA-PODS-ZEGFR:03115 showed similar pharmacokinetics and a specific tumor uptake of 14.1 ± 5.3% and 16.7 ± 4.5% ID/g at 1 h post-injection, respectively. The current results are encouraging for using PODS as an alternative to maleimide-based thiol-selective bioconjugation reactions.
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de Arcocha-Torres M, Quincoces G, Martínez-López AL, Erhard A, Collantes M, Martínez-Rodríguez I, Ecay M, Banzo I, Irache JM, Peñuelas I. Preparation, radiolabeling with 99mTc and 67Ga and biodistribution studies of albumin nanoparticles covered with polymers. Rev Esp Med Nucl Imagen Mol 2020; 39:225-232. [PMID: 32201272 DOI: 10.1016/j.remn.2020.02.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Revised: 01/28/2020] [Accepted: 02/06/2020] [Indexed: 01/06/2023]
Abstract
OBJECTIVE To optimize radiolabeling with 99mTc and 67Ga of albumin nanoparticles coated with 4 differents synthetic polymers and to evaluate their stability in vivo and in vitro, as well as their biodistribution in vivo after intravenous administration. MATERIAL AND METHODS The nanoparticles were prepared using albumin and NOTA-modified albumin by the desolvation method and coated with 4 different polymers; HPMC, GMN2, GPM2 and GTM2. They were purified, lyophilized and characterized. Radiolabelling with 99mTc was perfomed with 74 MBq of 99mTc sodium pertechnetate, previously reduced with and acid solution of tin chloride at different concentrations (0.003, 0.005, 0.007, 0.01, 0.05 and 0.1mg/ml) and at different times (5, 10, 15, 30 and 60minutes) and temperatures (room temperature, 40°C and 60°C). Radiolabelling with 67Ga was perfomed by incubation of the nanoparticles with 37 MBq of 67Gallium chloride (obtained from commercial gallium-67 citrate) at different times (10 and 30minutes) and temperatures (room temperature, 30°C and 60°C), and posterior purification with microconcentrators. The radiochemical purity was evaluated by TLC. Stability studies of radiolabeled nanoparticles in physiological serum and blood plasma were perfomed. Biodistribution studies of nanoparticles coated with GPM2 polymer were carried out in Wistar rats after intravenous administration of the nanoparticles. Control animals were carried out with 99mTc sodium pertechnetate and 67Ga chloride. To do so, the animals were killed and activity in organs was measured in a gamma counter. RESULTS 99mTc labeling was carried out optimally with a tin concentration of 0.007mg/ ml for the GPM2 nanoparticles and 0.005mg / ml for the rest of the formulations, with a radiolabelling time of 10minutes at room temperature. In the case of 67Ga the label was optimized at 30° C temperature and 30minutes of incubation. In both cases the radiochemical purity obtained was greater than 97%. The nanoparticles showed high stability in vitro after 48hours of labeling (70% nanoparticles labeled with 99mTc and 90% those labeled with 67Ga). Biodistribution studies of nanoparticles 99mTc -GPM2 and 67Ga -NOTA-GPM2 showed a high accumulation of activity in the liver at 2 and 24hours after intravenous administration. CONCLUSION The labeling procedure with 99mTc and 67Ga of albumin and albumin modified with NOTA nanoparticles allows obtaining nanoparticles with high labeling yields and adequate in vitro stability, allowing their use for in vivo studies.
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Affiliation(s)
- M de Arcocha-Torres
- Servicio Medicina Nuclear, Hospital Universitario Marqués de Valdecilla, Santander, España; Grupo de investigación Imagen Molecular (IDIVAL), Universidad de Cantabria, Santander, España.
| | - G Quincoces
- Unidad de Radiofarmacia, Servicio Medicina Nuclear, Clínica Universidad de Navarra, IdiSNA, Pamplona, España
| | - A L Martínez-López
- Departamento de Tecnología y Química Farmacéutica, Universidad de Navarra, Pamplona, España
| | - A Erhard
- Unidad de Radiofarmacia, Servicio Medicina Nuclear, Clínica Universidad de Navarra, IdiSNA, Pamplona, España
| | - M Collantes
- Unidad de investigación micropet, Servicio Medicina Nuclear, Clínica Universidad de Navarra, IdiSNA, Pamplona, España
| | - I Martínez-Rodríguez
- Servicio Medicina Nuclear, Hospital Universitario Marqués de Valdecilla, Santander, España; Grupo de investigación Imagen Molecular (IDIVAL), Universidad de Cantabria, Santander, España
| | - M Ecay
- Unidad de investigación micropet, Servicio Medicina Nuclear, Clínica Universidad de Navarra, IdiSNA, Pamplona, España
| | - I Banzo
- Servicio Medicina Nuclear, Hospital Universitario Marqués de Valdecilla, Santander, España; Grupo de investigación Imagen Molecular (IDIVAL), Universidad de Cantabria, Santander, España
| | - J M Irache
- Departamento de Tecnología y Química Farmacéutica, Universidad de Navarra, Pamplona, España
| | - I Peñuelas
- Unidad de Radiofarmacia, Servicio Medicina Nuclear, Clínica Universidad de Navarra, IdiSNA, Pamplona, España
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Rinne SS, Dahlsson Leitao C, Saleh-Nihad Z, Mitran B, Tolmachev V, Ståhl S, Löfblom J, Orlova A. Benefit of Later-Time-Point PET Imaging of HER3 Expression Using Optimized Radiocobalt-Labeled Affibody Molecules. Int J Mol Sci 2020; 21:ijms21061972. [PMID: 32183096 PMCID: PMC7139902 DOI: 10.3390/ijms21061972] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Revised: 03/09/2020] [Accepted: 03/11/2020] [Indexed: 02/07/2023] Open
Abstract
HER3-binding affibody molecules are a promising format for visualization of HER3 expression. Cobalt-55, a positron-emitting isotope, with a half-life of 17.5 h, allows for next-day imaging. We investigated the influence of the charge of the radiocobalt–chelator complex on the biodistribution of anti-HER3 affibody molecule (HE)3-ZHER3 and compared the best radiocobalt-labeled variant with a recently optimized gallium-labeled variant. Affibody conjugates (HE)3-ZHER3-X (X = NOTA, NODAGA, DOTA, DOTAGA) were labeled with [57Co]Co (surrogate for 55Co). Affinity measurements, binding specificity and cellular processing were studied in two HER3-expressing cancer cell lines. Biodistribution was studied 3 and 24 h post-injection (pi) in mice with HER3-expressing BxPC-3 xenografts and compared to [68Ga]Ga-(HE)3-ZHER3-NODAGA. Micro-single-photon emission tomography/computed tomography (microSPECT/CT) and micro-positron emission tomography/computed tomography (microPET/CT) imaging was performed 3 and 24 h pi. Stably labeled conjugates bound to HER3 with subnanomolar affinity. [57Co]Co-(HE)3-ZHER3-DOTA had the best tumor retention and a significantly lower concentration in blood than other conjugates, leading to superior tumor-to-blood and tumor-to-liver ratios 24 h pi. Compared to [68Ga]Ga-(HE)3-ZHER3-NODAGA 3 h pi, [57Co]Co-(HE)3-ZHER3-DOTA provided superior imaging contrast in liver 24 h pi. Concluding, the composition and charge of the [57Co]Co–chelator complex influenced the uptake in tumors and normal tissue. [57Co]Co-(HE)3-ZHER3-DOTA provided the best imaging properties among the cobalt-labeled conjugates. Delayed imaging of HER3 expression with [57Co]Co-(HE)3-ZHER3-DOTA improved imaging contrast compared to early-time-point imaging with [68Ga]Ga-(HE)3-ZHER3-NODAGA.
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Affiliation(s)
- Sara S Rinne
- Department of Medicinal Chemistry, Uppsala University, 751 83 Uppsala, Sweden
| | - Charles Dahlsson Leitao
- Department of Protein Science, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, 106 91 Stockholm, Sweden
| | - Zahra Saleh-Nihad
- Department of Medicinal Chemistry, Uppsala University, 751 83 Uppsala, Sweden
| | - Bogdan Mitran
- Department of Medicinal Chemistry, Uppsala University, 751 83 Uppsala, Sweden
| | - Vladimir Tolmachev
- Department of Immunology, Genetics and Pathology, Uppsala University, 751 85 Uppsala, Sweden
- Research Centrum for Oncotheranostics, Research School of Chemistry and Applied Biomedical Sciences, Tomsk Polytechnic University, 634050 Tomsk, Russia
| | - Stefan Ståhl
- Department of Protein Science, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, 106 91 Stockholm, Sweden
| | - John Löfblom
- Department of Protein Science, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, 106 91 Stockholm, Sweden
| | - Anna Orlova
- Department of Medicinal Chemistry, Uppsala University, 751 83 Uppsala, Sweden
- Research Centrum for Oncotheranostics, Research School of Chemistry and Applied Biomedical Sciences, Tomsk Polytechnic University, 634050 Tomsk, Russia
- Science for Life Laboratory, Uppsala University, 752 37 Uppsala, Sweden
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Fersing C, Bouhlel A, Cantelli C, Garrigue P, Lisowski V, Guillet B. A Comprehensive Review of Non-Covalent Radiofluorination Approaches Using Aluminum [ 18F]fluoride: Will [ 18F]AlF Replace 68Ga for Metal Chelate Labeling? Molecules 2019; 24:molecules24162866. [PMID: 31394799 PMCID: PMC6719958 DOI: 10.3390/molecules24162866] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Revised: 07/31/2019] [Accepted: 08/06/2019] [Indexed: 12/20/2022] Open
Abstract
Due to its ideal physical properties, fluorine-18 turns out to be a key radionuclide for positron emission tomography (PET) imaging, for both preclinical and clinical applications. However, usual biomolecules radiofluorination procedures require the formation of covalent bonds with fluorinated prosthetic groups. This drawback makes radiofluorination impractical for routine radiolabeling, gallium-68 appearing to be much more convenient for the labeling of chelator-bearing PET probes. In response to this limitation, a recent expansion of the 18F chemical toolbox gave aluminum [18F]fluoride chemistry a real prominence since the late 2000s. This approach is based on the formation of an [18F][AlF]2+ cation, complexed with a 9-membered cyclic chelator such as NOTA, NODA or their analogs. Allowing a one-step radiofluorination in an aqueous medium, this technique combines fluorine-18 and non-covalent radiolabeling with the advantage of being very easy to implement. Since its first reports, [18F]AlF radiolabeling approach has been applied to a wide variety of potential PET imaging vectors, whether of peptidic, proteic, or small molecule structure. Most of these [18F]AlF-labeled tracers showed promising preclinical results and have reached the clinical evaluation stage for some of them. The aim of this report is to provide a comprehensive overview of [18F]AlF labeling applications through a description of the various [18F]AlF-labeled conjugates, from their radiosynthesis to their evaluation as PET imaging agents.
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Affiliation(s)
- Cyril Fersing
- Institut de Recherche en Cancérologie de Montpellier (IRCM), University of Montpellier, INSERM U1194, Montpellier Cancer Institute (ICM), 34298 Montpellier, France.
- Nuclear Medicine Department, Montpellier Cancer Institute (ICM), University of Montpellier, 208 Avenue des Apothicaires, 34298 Montpellier CEDEX 5, France.
| | - Ahlem Bouhlel
- CERIMED, Aix-Marseille University, 13005 Marseille, France
- Centre de recherche en CardioVasculaire et Nutrition (C2VN), Aix-Marseille University, INSERM 1263, INRA 1260, 13385 Marseille, France
| | - Christophe Cantelli
- Institut de Recherche en Cancérologie de Montpellier (IRCM), University of Montpellier, INSERM U1194, Montpellier Cancer Institute (ICM), 34298 Montpellier, France
- Institut des Biomolécules Max Mousseron, UMR 5247, CNRS, Université de Montpellier, ENSCM, UFR des Sciences Pharmaceutiques et Biologiques, 34093 Montpellier CEDEX, France
| | - Philippe Garrigue
- CERIMED, Aix-Marseille University, 13005 Marseille, France
- Centre de recherche en CardioVasculaire et Nutrition (C2VN), Aix-Marseille University, INSERM 1263, INRA 1260, 13385 Marseille, France
- Department of Nuclear Medicine, Aix-Marseille University, Assistance Publique-Hôpitaux de Marseille (AP-HM), 13385 Marseille, France
| | - Vincent Lisowski
- Institut des Biomolécules Max Mousseron, UMR 5247, CNRS, Université de Montpellier, ENSCM, UFR des Sciences Pharmaceutiques et Biologiques, 34093 Montpellier CEDEX, France
| | - Benjamin Guillet
- CERIMED, Aix-Marseille University, 13005 Marseille, France
- Centre de recherche en CardioVasculaire et Nutrition (C2VN), Aix-Marseille University, INSERM 1263, INRA 1260, 13385 Marseille, France
- Department of Nuclear Medicine, Aix-Marseille University, Assistance Publique-Hôpitaux de Marseille (AP-HM), 13385 Marseille, France
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10
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Liu F, Zhao B, Xia XT, Yan JR, Yu FQ, Yan GP, Hu J, Chen S, Wang YF, Liu H, Lan XL, Zhang YX. Al 18 F labeled sulfonamide-conjugated positron emission tomography tracer in vivo tumor-targeted imaging. J Cell Biochem 2019; 120:17006-17014. [PMID: 31131464 DOI: 10.1002/jcb.28961] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Accepted: 03/06/2019] [Indexed: 01/01/2023]
Abstract
An ideal positron emission tomography (PET) tracer should be highly extractable by the tumor tissue or organ that contains low toxicity and can provide high-resolution images in vivo. In this work, the aim was to evaluate the application of Al18 F-labeled 1,4,7-triazacyclononane-1,4,7-triacetic acid containing sulfonamide group (18 F-Al-NOTA-SN) as a potential tumor-targeting signal-enhanced radioactive tracer in PET. SN as a tumor-targeting group was incorporated to NOTA to make a ligand. Subsequently, this ligand reacted with Na18 F and AlCl3 to produce a compound 18 F-Al-NOTA-SN. This compound was further characterized and its property in regard to cell cytotoxicity assay, microPET imaging, biodistribution, cell uptake assay, and tumor selectivity in vitro and in vivo, was also investigated. 18 F-Al-NOTA-SN possessed low cell cytotoxicity and uptake to COS-7 and 293T healthy cells and high cell cytotoxicity and uptake to MDA-MB-231, HepG2, and HeLa tumor cells in vitro. Moreover, 18 F-Al-NOTA-SN showed good tumor-targeting property and high PET signal enhancement of HeLa tumors, liver, and kidneys in mice, as well as the uptake ratios of tumor to blood and tumor to muscle, were 4.98 and 3.87, respectively. 18 F-Al-NOTA-SN can be accepted to be kidney and liver eliminated earlier and show a potential tumor-targeting signal-enhanced radioactive tracer in PET.
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Affiliation(s)
- Fan Liu
- School of Chemical Engineering and Pharmacy, Wuhan Institute of Technology, Wuhan, China.,School of Chemistry, Physics, and Mechanical Engineering, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Biao Zhao
- School of Materials Science and Engineering, Wuhan Institute of Technology, Wuhan, China
| | - Xiao-Tian Xia
- Center for PET of Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jia-Rui Yan
- School of Materials Science and Engineering, Wuhan Institute of Technology, Wuhan, China
| | - Fa-Quan Yu
- School of Chemical Engineering and Pharmacy, Wuhan Institute of Technology, Wuhan, China
| | - Guo-Ping Yan
- School of Materials Science and Engineering, Wuhan Institute of Technology, Wuhan, China
| | - Jia Hu
- Center for PET of Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Si Chen
- School of Materials Science and Engineering, Wuhan Institute of Technology, Wuhan, China
| | - Yu-Fang Wang
- School of Materials Science and Engineering, Wuhan Institute of Technology, Wuhan, China
| | - Hui Liu
- School of Materials Science and Engineering, Wuhan Institute of Technology, Wuhan, China
| | - Xiao-Li Lan
- Center for PET of Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yong-Xue Zhang
- Center for PET of Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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11
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von Witting E, Garousi J, Lindbo S, Vorobyeva A, Altai M, Oroujeni M, Mitran B, Orlova A, Hober S, Tolmachev V. Selection of the optimal macrocyclic chelators for labeling with 111In and 68Ga improves contrast of HER2 imaging using engineered scaffold protein ADAPT6. Eur J Pharm Biopharm 2019; 140:109-120. [PMID: 31082509 DOI: 10.1016/j.ejpb.2019.05.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Revised: 05/07/2019] [Accepted: 05/09/2019] [Indexed: 12/16/2022]
Abstract
Radionuclide molecular imaging is a promising tool that becomes increasingly important as targeted cancer therapies are developed. To ensure an effective treatment, a molecular stratification of the cancer is a necessity. To accomplish this, visualization of cancer associated molecular abnormalities in vivo by molecular imaging is the method of choice. ADAPTs, a novel type of small protein scaffold, have been utilized to select and develop high affinity binders to different proteinaceous targets. One of these binders, ADAPT6 selectively interacts with human epidermal growth factor 2 (HER2) with low nanomolar affinity and can therefore be used for its in vivo visualization. Molecular design and optimization of labeled anti-HER2 ADAPT has been explored in several earlier studies, showing that small changes in the scaffold affect the biodistribution of the domain. In this study, we evaluate how the biodistribution properties of ADAPT6 is affected by the commonly used maleimido derivatives of the macrocyclic chelators NOTA, NODAGA, DOTA and DOTAGA with the aim to select the best variants for SPECT and PET imaging. The different conjugates were labeled with 111In for SPECT and 68Ga for PET. The acquired data show that the combination of a radionuclide and a chelator for its conjugation has a strong influence on the uptake of ADAPT6 in normal tissues and thereby gives a significant variation in tumor-to-organ ratios. Hence, it was concluded that the best variant for SPECT imaging is 111In-(HE)3DANS-ADAPT6-GSSC-DOTA while the best variant for PET imaging is 68Ga-(HE)3DANS-ADAPT6-GSSC-NODAGA.
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Affiliation(s)
- Emma von Witting
- Department of Protein Science, KTH - Royal Institute of Technology, SE-10691 Stockholm, Sweden
| | - Javad Garousi
- Department of Immunology, Genetics and Pathology, Uppsala University, SE-75185 Uppsala, Sweden
| | - Sarah Lindbo
- Department of Protein Science, KTH - Royal Institute of Technology, SE-10691 Stockholm, Sweden
| | - Anzhelika Vorobyeva
- Department of Immunology, Genetics and Pathology, Uppsala University, SE-75185 Uppsala, Sweden
| | - Mohamed Altai
- Department of Immunology, Genetics and Pathology, Uppsala University, SE-75185 Uppsala, Sweden
| | - Maryam Oroujeni
- Department of Immunology, Genetics and Pathology, Uppsala University, SE-75185 Uppsala, Sweden
| | - Bogdan Mitran
- Department of Medicinal Chemistry, Uppsala University, Uppsala, Sweden
| | - Anna Orlova
- Department of Medicinal Chemistry, Uppsala University, Uppsala, Sweden
| | - Sophia Hober
- Department of Protein Science, KTH - Royal Institute of Technology, SE-10691 Stockholm, Sweden.
| | - Vladimir Tolmachev
- Department of Immunology, Genetics and Pathology, Uppsala University, SE-75185 Uppsala, Sweden
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12
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Dahlsson Leitao C, Rinne SS, Mitran B, Vorobyeva A, Andersson KG, Tolmachev V, Ståhl S, Löfblom J, Orlova A. Molecular Design of HER3-Targeting Affibody Molecules: Influence of Chelator and Presence of HEHEHE-Tag on Biodistribution of 68Ga-Labeled Tracers. Int J Mol Sci 2019; 20:E1080. [PMID: 30832342 DOI: 10.3390/ijms20051080] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Revised: 02/13/2019] [Accepted: 02/26/2019] [Indexed: 12/27/2022] Open
Abstract
Affibody-based imaging of HER3 is a promising approach for patient stratification. We investigated the influence of a hydrophilic HEHEHE-tag ((HE)3-tag) and two different gallium-68/chelator-complexes on the biodistribution of Z08698 with the aim to improve the tracer for PET imaging. Affibody molecules (HE)3-Z08698-X and Z08698-X (X = NOTA, NODAGA) were produced and labeled with gallium-68. Binding specificity and cellular processing were studied in HER3-expressing human cancer cell lines BxPC-3 and DU145. Biodistribution was studied 3 h p.i. in Balb/c nu/nu mice bearing BxPC-3 xenografts. Mice were imaged 3 h p.i. using microPET/CT. Conjugates were stably labeled with gallium-68 and bound specifically to HER3 in vitro and in vivo. Association to cells was rapid but internalization was slow. Uptake in tissues, including tumors, was lower for (HE)3-Z08698-X than for non-tagged variants. The neutral [68Ga]Ga-NODAGA complex reduced the hepatic uptake of Z08698 compared to positively charged [68Ga]Ga-NOTA-conjugated variants. The influence of the chelator was more pronounced in variants without (HE)3-tag. In conclusion, hydrophilic (HE)3-tag and neutral charge of the [68Ga]Ga-NODAGA complex promoted blood clearance and lowered hepatic uptake of Z08698. [68Ga]Ga-(HE)3-Z08698-NODAGA was considered most promising, providing the lowest blood and hepatic uptake and the best imaging contrast among the tested variants.
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13
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Pulido J, de Cabrera M, Sobczak AJ, Amor-Coarasa A, McGoron AJ, Wnuk SF. 4-N-Alkanoyl and 4-N-alkyl gemcitabine analogues with NOTA chelators for 68-gallium labelling. Bioorg Med Chem 2018; 26:5624-5630. [PMID: 30342865 DOI: 10.1016/j.bmc.2018.10.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Revised: 10/03/2018] [Accepted: 10/11/2018] [Indexed: 02/08/2023]
Abstract
The conjugation of 4-N-(3-aminopropanyl)-2'-deoxy-2',2'-difluorocytidine with 2-(p-isothiocyanatobenzyl)-1,4,7-triazacyclononane-1,4,7-triacetic acid (SCN-Bn-NOTA) ligand in 0.1 M Na2CO3 buffer (pH 11) at ambient temperature provided 4-N-alkylgemcitabine-NOTA chelator. Incubation of latter with excess of gallium(III) chloride (GaCl3) (0.6 N AcONa/H2O, pH = 9.3) over 15 min gave gallium 4-N-alkylgemcitabine-NOTA complex which was characterized by HRMS. Analogous [68Ga]-complexation of 4-N-alkylgemcitabine-NOTA conjugate proceeded with high labeling efficiency (94%-96%) with the radioligand almost exclusively found in the aqueous layer (∼95%). The high polarity of the gallium 4-N-alkylgemctiabine-NOTA complex resulted in rapid renal clearance of the 68Ga-labelled radioligand in BALB/c mice.
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Affiliation(s)
- Jesse Pulido
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, United States
| | - Maria de Cabrera
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, United States
| | - Adam J Sobczak
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, United States
| | - Alejandro Amor-Coarasa
- Department of Biomedical Engineering, Florida International University, Miami, FL 33199, United States
| | - Anthony J McGoron
- Department of Biomedical Engineering, Florida International University, Miami, FL 33199, United States
| | - Stanislaw F Wnuk
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, United States.
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14
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Jain A, Mathur A, Pandey U, Sarma HD, Dash A. Synthesis and evaluation of 68Ga labeled palmitic acid for cardiac metabolic imaging. Appl Radiat Isot 2018; 140:35-40. [PMID: 29936274 DOI: 10.1016/j.apradiso.2018.06.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Revised: 04/17/2018] [Accepted: 06/03/2018] [Indexed: 11/26/2022]
Abstract
This work evaluates the potential of a 68Ga labeled long chain 16C fatty acid for cardiac metabolic imaging. For radiolabeling with 68Ga, hexadecanedioic acid was coupled with the chelator p-NH2-Bn-NOTA. Under the optimized conditions, NOTA-hexadecanoic acid could be radiolabeled with 68Ga in ≥95% yields. In biodistribution studies carried out in Swiss mice, 68Ga-NOTA-hexadecanoic acid showed low myocardial uptake at 2 min p.i. (3.7 ± 1.3%ID/g). While 68Ga-NOTA-hexadecanoic acid cleared rapidly from non-target organs such as blood, lungs, intestine and kidney, wash out from liver was slow. Radio-HPLC analyses of myocardial extracts of rats injected with 68Ga-NOTA-hexadecanoic acid confirmed its metabolic transformation in the myocardium.
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Affiliation(s)
- Akanksha Jain
- Radiopharmaceuticals Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085, India; Homi Bhabha National Institute, Anushaktinagar, Mumbai 400094, India
| | - Anupam Mathur
- Radiopharmaceuticals Program, Board of Radiation and Isotope Technology, Navi Mumbai 400703, India
| | - Usha Pandey
- Radiopharmaceuticals Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085, India; Homi Bhabha National Institute, Anushaktinagar, Mumbai 400094, India.
| | - Haladhar Dev Sarma
- Radiation Biology & Health Sciences Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085, India
| | - Ashutosh Dash
- Radiopharmaceuticals Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085, India; Homi Bhabha National Institute, Anushaktinagar, Mumbai 400094, India
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15
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O'Connell EP, White A, Cromwell P, Carroll E, Khan W, Waldron R, Khan IZ, Barry K. Non-operative treatment of appendicitis: public perception and decision-making. Ir J Med Sci 2018; 187:1029-1038. [PMID: 29423825 DOI: 10.1007/s11845-018-1758-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Accepted: 01/24/2018] [Indexed: 12/22/2022]
Abstract
BACKGROUND Appendectomy has for many years been the accepted treatment of appendicitis. In recent years, non-operative management of appendicitis (NOTA) has been reported as an effective treatment option. AIMS We aimed to assess the perspectives of public hospital attendees regarding the diagnosis and treatment options for appendicitis. METHODS We conducted a cross-sectional survey of outpatients over a 10-week period (December 2016-March 2017). The questionnaire contained an information sheet and consent form and included open, closed and multiple-choice questions. RESULTS Two hundred forty-four participants (159 female, 85 male) were surveyed. A high level of awareness of appendicitis as a surgical emergency existed amongst the participants. The primary reason participants were reluctant to receive non-operative treatment was a fear of their appendix "bursting" if not removed. CONCLUSIONS Participant knowledge levels were variable with many concerned that non-operated appendicitis would always perforate. Perceptions of treatment were variable with some believing surgery was an absolute requirement and others preferring antibiotics due to the belief that NOTA is complication-free.
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Affiliation(s)
- Emer P O'Connell
- Department of Surgery, Mayo University Hospital, Castlebar, Mayo, Ireland.
| | - Annmarie White
- Department of Surgery, Mayo University Hospital, Castlebar, Mayo, Ireland
| | - Paul Cromwell
- Department of Surgery, Mayo University Hospital, Castlebar, Mayo, Ireland
| | - Emma Carroll
- Discipline of Surgery, National University of Ireland, Galway, Ireland
| | - Waqar Khan
- Department of Surgery, Mayo University Hospital, Castlebar, Mayo, Ireland
| | - Ronan Waldron
- Department of Surgery, Mayo University Hospital, Castlebar, Mayo, Ireland
| | - Iqbal Z Khan
- Department of Surgery, Mayo University Hospital, Castlebar, Mayo, Ireland
| | - Kevin Barry
- Department of Surgery, Mayo University Hospital, Castlebar, Mayo, Ireland.,Discipline of Surgery, National University of Ireland, Galway, Ireland
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16
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Sicco E, Báez J, Margenat J, García F, Ibarra M, Cabral P, Moreno M, Cerecetto H, Calzada V. Derivatizations of Sgc8-c aptamer to prepare metallic radiopharmaceuticals as imaging diagnostic agents: Syntheses, isolations, and physicochemical characterizations. Chem Biol Drug Des 2017; 91:747-755. [PMID: 29080264 DOI: 10.1111/cbdd.13135] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Revised: 07/09/2017] [Accepted: 10/04/2017] [Indexed: 12/31/2022]
Abstract
Aptamers, oligonucleotides with the capability to bind to a target through non-covalent bonds with high affinity and specificity, have a great number of advantages as scaffold to prepare molecular imaging agents. In this sense, we have performed post-SELEX modifications of a truncated aptamer, Sgc8-c, which bind to protein tyrosine kinase 7 to obtain a specific molecular targeting probe for in vivo diagnosis and in vivo therapy. Herein, we describe the synthetic efforts to prepare conjugates between Sgc8-c and different metallic ions chelator moieties in short times, high purities, and adequate yields. The selected chelator moieties, derived from 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid, 2-benzyl-1,4,7-triazacyclononane-1,4,7-triacetic acid, and 6-hydrazinonicotinic acid, were covalently attached at the 5'-aptamer position yielding the expected products which were stable in aqueous solution up to 75°C and in typical aptamer storage conditions at least for 30 days.
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Affiliation(s)
- Estefanía Sicco
- Área de Radiofarmacia, Facultad de Ciencias, Centro de Investigaciones Nucleares, Universidad de la República, Montevideo, Uruguay.,Departamento de Desarrollo Biotecnológico, Facultad de Medicina, Instituto de Higiene, Universidad de la República, Montevideo, Uruguay
| | - Jessica Báez
- Área de Radiofarmacia, Facultad de Ciencias, Centro de Investigaciones Nucleares, Universidad de la República, Montevideo, Uruguay.,Facultad de Química, Centro de Evaluación de Biodisponibilidad y Bioequivalencia de Medicamentos, Universidad de la República, Montevideo, Uruguay
| | - Jimena Margenat
- Área de Radiofarmacia, Facultad de Ciencias, Centro de Investigaciones Nucleares, Universidad de la República, Montevideo, Uruguay
| | - Fernanda García
- Área de Radiofarmacia, Facultad de Ciencias, Centro de Investigaciones Nucleares, Universidad de la República, Montevideo, Uruguay
| | - Manuel Ibarra
- Facultad de Química, Centro de Evaluación de Biodisponibilidad y Bioequivalencia de Medicamentos, Universidad de la República, Montevideo, Uruguay
| | - Pablo Cabral
- Área de Radiofarmacia, Facultad de Ciencias, Centro de Investigaciones Nucleares, Universidad de la República, Montevideo, Uruguay
| | - María Moreno
- Departamento de Desarrollo Biotecnológico, Facultad de Medicina, Instituto de Higiene, Universidad de la República, Montevideo, Uruguay
| | - Hugo Cerecetto
- Área de Radiofarmacia, Facultad de Ciencias, Centro de Investigaciones Nucleares, Universidad de la República, Montevideo, Uruguay
| | - Victoria Calzada
- Área de Radiofarmacia, Facultad de Ciencias, Centro de Investigaciones Nucleares, Universidad de la República, Montevideo, Uruguay
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17
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Poschenrieder A, Schottelius M, Osl T, Schwaiger M, Wester HJ. [ 64Cu] NOTA-pentixather enables high resolution PET imaging of CXCR4 expression in a preclinical lymphoma model. EJNMMI Radiopharm Chem 2017; 2:2. [PMID: 29527563 PMCID: PMC5835975 DOI: 10.1186/s41181-016-0020-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2016] [Accepted: 12/22/2016] [Indexed: 01/29/2023] Open
Abstract
BACKGROUND The chemokine receptor 4 (CXCR4) is an important molecular target for both visualization and therapy of tumors. The aim of the present study was the synthesis and preclinical evaluation of a 64Cu-labeled, CXCR4-targeting peptide for positron emission tomography (PET) imaging of CXCR4 expression in vivo. METHODS For this purpose, 1,4,7-triazacyclononane,1-glutaric acid-4,7-acetic acid (NODAGA), or 1,4,7-triazacyclononane-triacetic acid (NOTA) was conjugated to the highly affine CXCR4-targeting pentixather scaffold. Affinities were determined using Jurkat T-lymphocytes in competitive binding assays employing [125I]FC131 as the radioligand. Internalization and efflux studies of [64Cu]NOTA-pentixather were performed in chem-1 cells, stably transfected with hCXCR4. The stability of the tracer was evaluated in vitro and in vivo. Small-animal PET and biodistribution studies at different time points were performed in Daudi lymphoma-bearing severe combined immunodeficiency (SCID) mice. RESULTS [64Cu]NOTA-pentixather was rapidly radiolabeled at 60 °C with high radiochemical yields ≥90% and purities >99%. [64Cu]NOTA-pentixather offered the highest affinity of the evaluated peptides in this study (IC50 = 14.9 ± 2.1 nM), showed efficient CXCR4-targeting in vitro and was stable in blood and urine with high resistance to transchelation in ethylenediaminetetraacetic acid (EDTA) challenge studies. Due to the enhanced lipophilicity of [64Cu]NOTA-pentixather (logP = -1.2), biodistribution studies showed some nonspecific accumulation in the liver and intestines. However, tumor accumulation (13.1 ± 1.5% ID/g, 1.5 h p.i.) was CXCR4-specific and higher than in all other organs and resulted in high resolution delineation of Daudi tumors in PET/CT images in vivo. CONCLUSIONS [64Cu]NOTA-pentixather was fast and efficiently radiolabeled, showed effective CXCR4-targeting, high stability in vitro and in vivo and resulted in high resolution PET/CT images accompanied with a suitable biodistribution profile, making [64Cu]NOTA-pentixather a promising tracer for future application in humans.
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Affiliation(s)
- Andreas Poschenrieder
- Pharmaceutical Radiochemistry, Technische Universität München, Walther-Meißner-Str.3, 85748 Garching, Germany
| | - Margret Schottelius
- Pharmaceutical Radiochemistry, Technische Universität München, Walther-Meißner-Str.3, 85748 Garching, Germany
| | - Theresa Osl
- Pharmaceutical Radiochemistry, Technische Universität München, Walther-Meißner-Str.3, 85748 Garching, Germany
| | - Markus Schwaiger
- Department of Nuclear Medicine, Klinikum rechts der Isar, Technische Universität München, Ismaningerstr. 22, 81675 Munich, Germany
| | - Hans-Jürgen Wester
- Pharmaceutical Radiochemistry, Technische Universität München, Walther-Meißner-Str.3, 85748 Garching, Germany
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18
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Jain A, Mathur A, Pandey U, Sarma HD, Dash A. 68Ga labeled fatty acids for cardiac metabolic imaging: Influence of different bifunctional chelators. Bioorg Med Chem Lett 2016; 26:5785-5791. [PMID: 27793567 DOI: 10.1016/j.bmcl.2016.10.048] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Revised: 08/18/2016] [Accepted: 10/14/2016] [Indexed: 02/02/2023]
Abstract
Development of 68Ga labeled fatty acids is of immense interest due to the availability of 68Ga through a generator and its superiority over SPECT based tracers in carrying out dynamic imaging on a PET scanner. Our present work explores the influence of different chelators on the cardiac uptake and pharmacokinetics of the 68Ga-labeled fatty acids. Two new 68Ga labeled fatty acids were synthesized by conjugation of 11-aminoundecanoic acid with the bifunctional chelators (BFCs) viz. p-SCN-Bn-DTPA (S-2-(4-isothiocyanatobenzyl)-diethylenetriaminepentaacetic acid) and p-SCN-Bn-NODAGA (S-2-(4-isothiocyanatobenzyl)-1,4,7-triazacyclononane-1-glutaric acid-4,7-acetic acid) and their comparison was carried out with the previously reported 68Ga-NOTA-undecanoic acid. Both the conjugates were radiolabeled with 68Ga in high yields and purities (>95%). Their formation was established by preparation and characterization of their inactive analogs with natGa at macroscopic levels. Biodistribution studies of the complexes in Swiss mice showed lower initial myocardial uptake for 68Ga-NODAGA-undecanoic acid (3.8±0.6%ID/g) and 68Ga-DTPA-undecanoic acid (1.3±0.5%ID/g) complexes in comparison to previously reported 68Ga-NOTA-undecanoic acid complex (7.4±2.8%ID/g) at 2min p.i. However, significant retention of the tracer in the myocardium was observed in the case of 68Ga-NODAGA-undecanoic complex, which led to improved heart/non-target ratios of the complex over time in comparison to the other 68Ga complexes. Similarly, the DTPA complex exhibited increased washout from the liver in comparison to other 68Ga derivatives. The β oxidation mechanism in myocytes was investigated by isolating the myocardial extract post intravenous injection of the respective 68Ga complexes and analyzing them by radio-HPLC, which showed metabolic transformation of the parent fatty acid complex peak in all the three complexes. This study has provided an insight into the design characteristics of 68Ga labeled fatty acids to achieve the desired myocardial imaging characteristics.
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Affiliation(s)
- Akanksha Jain
- Radiopharmaceuticals Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085, India
| | - Anupam Mathur
- Radiopharmaceuticals Program, Board of Radiation and Isotope Technology, Navi Mumbai 400 703, India
| | - Usha Pandey
- Radiopharmaceuticals Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085, India
| | - Haladhar Dev Sarma
- Radiation Biology & Health Sciences Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085, India
| | - Ashutosh Dash
- Radiopharmaceuticals Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085, India.
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Poschenrieder A, Schottelius M, Schwaiger M, Wester HJ. Preclinical evaluation of [(68)Ga] NOTA-pentixafor for PET imaging of CXCR4 expression in vivo - a comparison to [(68)Ga]pentixafor. EJNMMI Res 2016; 6:70. [PMID: 27655427 PMCID: PMC5031577 DOI: 10.1186/s13550-016-0227-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Accepted: 09/17/2016] [Indexed: 01/20/2023] Open
Abstract
Background Due to its overexpression in a variety of tumor types, the chemokine receptor 4 (CXCR4) represents a highly relevant diagnostic and therapeutic target in nuclear oncology. Recently, [68Ga]pentixafor has emerged as an excellent imaging agent for positron emission tomography (PET) of CXCR4 expression in vivo. In this study, the corresponding [68Ga]-1,4,7-triazacyclononane-triacetic acid (NOTA) analog was preclinically evaluated and compared to the 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) parent compound [68Ga]pentixafor. Methods NOTA-pentixafor was synthesized by combining solid and solution-phase peptide synthesis. The CXCR4 receptor affinities of [68Ga]pentixafor and [68Ga]NOTA-pentixafor were determined in competitive binding assays using the leukemic CXCR4-expressing Jurkat T-cell line and [125I]FC131 as the radioligand. Internalization and cell efflux assays were performed using CXCR4-transfected Chem-1 cells. Small-animal PET and biodistribution studies were carried out using Daudi-tumor bearing SCID mice. Results [68Ga]NOTA-pentixafor showed a 1.4-fold improved affinity towards CXCR4 (IC50). However, internalization efficiency into CXCR4+-Chem-1 cells was substantially decreased compared to [68Ga]pentixafor. Accordingly, small-animal PET imaging and biodistribution studies revealed a 9.5-fold decreased uptake of [68Ga]NOTA-pentixafor in Daudi lymphoma xenografts (1.7 ± 0.4 % vs 16.2 ± 3.8 % ID/g at 90 min p.i.) and higher levels of non-specific accumulation, primarily in the excretory organs such as the liver, intestines, and kidneys (2.3 ± 0.9 % vs 2.0 ± 0.3 % ID/g, 1.9 ± 0.8 % vs 0.7 ± 0.2 % ID/g, and 2.7 ± 1.1 % vs 1.7 ± 0.9 % ID/g, respectively). Conclusions Despite enhanced CXCR4-affinity in vitro, the [68Ga]NOTA-analog of pentixafor showed reduced CXCR4 targeting efficiency in vivo. In combination with enhanced background accumulation, this resulted in significantly inferior PET imaging contrast, and thus, [68Ga]NOTA-pentixafor offers no advantages over [68Ga]pentixafor.
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Affiliation(s)
- Andreas Poschenrieder
- Pharmaceutical Radiochemistry, Technische Universität München, Walther-Meißner-Str.3, 85748, Garching, Germany.
| | - Margret Schottelius
- Pharmaceutical Radiochemistry, Technische Universität München, Walther-Meißner-Str.3, 85748, Garching, Germany
| | - Markus Schwaiger
- Nuklearmedizinische Klinik und Poliklinik, Klinikum rechts der Isar, Technische Universität München, Ismaningerstr. 22, 81675, München, Germany
| | - Hans-Jürgen Wester
- Pharmaceutical Radiochemistry, Technische Universität München, Walther-Meißner-Str.3, 85748, Garching, Germany
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Chang CC, Chang CH, Lo YH, Lin MH, Shen CC, Liu RS, Wang HE, Chen CL. Preparation and characterization of a novel Al(18)F- NOTA-BZA conjugate for melanin-targeted imaging of malignant melanoma. Bioorg Med Chem Lett 2016; 26:4133-9. [PMID: 27445169 DOI: 10.1016/j.bmcl.2016.06.022] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Revised: 06/07/2016] [Accepted: 06/09/2016] [Indexed: 11/16/2022]
Abstract
Melanin is an attractive target for the diagnosis and treatment of malignant melanoma. Previous studies have demonstrated the specific binding ability of benzamide moiety to melanin. In this study, we developed a novel (18)F-labeled NOTA-benzamide conjugate, Al(18)F-NOTA-BZA, which can be synthesized in 30min with a radiochemical yield of 20-35% and a radiochemical purity of >95%. Al(18)F-NOTA-BZA is highly hydrophilic (logP=-1.96) and shows good in vitro stability. Intravenous administration of Al(18)F-NOTA-BZA in two melanoma-bearing mouse models revealed highly specific uptake in B16F0 melanotic melanoma (6.67±0.91 and 1.50±0.26%ID/g at 15 and 120min p.i., respectively), but not in A375 amelanotic melanoma (0.87±0.21 and 0.24±0.09%ID/g at 15 and 120min p.i., respectively). The clearance from most normal tissues was fast. A microPET scan of Al(18)F-NOTA-BZA-injected mice also displayed high-contrast tumor images as compared with normal organs. Owing to the favorable in vivo distribution of Al(18)F-NOTA-BZA after intravenous administration, the estimated absorption dose was low in all normal organs and tissues. The melanin-specific binding ability, sustained tumor retention, fast normal tissues clearance and thelow projected human dosimetry supported that Al(18)F-NOTA-BZA is a very promising melanin-specific PET probe for melanin-positive melanoma.
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Affiliation(s)
- Chih-Chao Chang
- Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, No. 155, Li-Nong St., Sec. 2, Pei-tou, Taipei 11221, Taiwan
| | - Chih-Hsien Chang
- Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, No. 155, Li-Nong St., Sec. 2, Pei-tou, Taipei 11221, Taiwan; Isotope Application Division, Institute of Nuclear Energy Research, Taoyuan, Taiwan
| | - Yi-Hsuan Lo
- Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, No. 155, Li-Nong St., Sec. 2, Pei-tou, Taipei 11221, Taiwan
| | - Ming-Hsien Lin
- Department of Nuclear Medicine, Taipei City Hospital, Zhongxiao Branch, Taipei, Taiwan
| | - Chih-Chieh Shen
- Department of Nuclear Medicine, Cheng Hsin General Hospital, Taipei, Taiwan
| | - Ren-Shyan Liu
- Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, No. 155, Li-Nong St., Sec. 2, Pei-tou, Taipei 11221, Taiwan; Molecular and Genetic Imaging Core/Taiwan Mouse Clinic, National Comprehensive Mouse Phenotyping and Drug Testing Center, Taipei, Taiwan; National PET/Cyclotron Center and Department of Nuclear Medicine, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Hsin-Ell Wang
- Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, No. 155, Li-Nong St., Sec. 2, Pei-tou, Taipei 11221, Taiwan.
| | - Chuan-Lin Chen
- Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, No. 155, Li-Nong St., Sec. 2, Pei-tou, Taipei 11221, Taiwan.
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Poschenrieder A, Osl T, Schottelius M, Hoffmann F, Wirtz M, Schwaiger M, Wester HJ. First 18F-Labeled Pentixafor-Based Imaging Agent for PET Imaging of CXCR4 Expression In Vivo. ACTA ACUST UNITED AC 2016; 2:85-93. [PMID: 30042959 PMCID: PMC6024415 DOI: 10.18383/j.tom.2016.00130] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
In vivo quantification of CXCR4 expression using [68Ga]pentixafor for positron emission tomography (PET) imaging has gained significant clinical interest as CXCR4 plays a fundamental role in oncology and possesses potential prognostic value when overexpressed. To combine the excellent CXCR4-targeting properties of pentixafor-based tracers with the favorable radionuclide properties of 18F for high-resolution PET imaging, we developed an Al18F-labeled 1,4,7-triazacyclononane-triacetic acid (NOTA) analog of pentixather. Al18F-labeling of NOTA-pentixather was performed in aqueous dimethyl sulfoxide (DMSO) at pH = 4 (105°C, 15 minutes). CXCR4 affinities were determined in competitive binding assays, and both biodistribution and small-animal PET studies were performed in Daudi lymphoma-bearing mice. Under non-optimized conditions, [18F]AlF-NOTA-pentixather was obtained in radiochemical yields of 45.5% ± 13.3% and specific activities of up to 24.8 GBq/μmol. Compared with [natGa]pentixafor, [natF]AlF-NOTA-pentixather showed 1.4-fold higher CXCR4 affinity. [18F]AlF-NOTA-pentixather displayed high and CXCR4-specific in vivo uptake in Daudi xenografts (13.9% ± 0.8% injected dose per gram [ID/g] at 1 hour post injection [p.i.]). Because of its enhanced lipophilicity (logP = -1.4), [18F]AlF-NOTA-pentixather showed increased accumulation in the gall bladder and intestines. However, tumor/background ratios of 7.0 ± 1.2, 2.0 ± 0.3, 2.2 ± 0.4, 16.5 ± 6.5, and 29.2 ± 4 for blood, liver, small intestine, gut, and muscle, respectively, allowed for high-contrast visualization of Daudi tumors using PET (1 hour p.i.). The relatively straightforward radiosynthesis and efficient CXCR4 targeting of [18F]AlF-NOTA-pentixather demonstrate the successful implementation of 18F-complexation chemistry and pentixather-based CXCR4 targeting. Upon pharmacokinetic optimization, this class of tracers holds great promise for future application in humans.
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Affiliation(s)
| | - Theresa Osl
- Pharmaceutical Radiochemistry, Technische Universität München, Germany and
| | | | - Frauke Hoffmann
- Pharmaceutical Radiochemistry, Technische Universität München, Germany and
| | - Martina Wirtz
- Pharmaceutical Radiochemistry, Technische Universität München, Germany and
| | - Markus Schwaiger
- Nuklearmedizinische Klinik und Poliklinik, Technische Universität München, Ismaningerstr, München, Germany
| | - Hans-Jürgen Wester
- Pharmaceutical Radiochemistry, Technische Universität München, Germany and
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22
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Satpati D, Arjun C, Krishnamohan R, Samuel G, Banerjee S. (68) Ga-labeled Ciprofloxacin Conjugates as Radiotracers for Targeting Bacterial Infection. Chem Biol Drug Des 2015; 87:680-6. [PMID: 26647765 DOI: 10.1111/cbdd.12701] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Revised: 09/08/2015] [Accepted: 11/24/2015] [Indexed: 02/06/2023]
Abstract
With an aim of developing a bacteria-specific molecular imaging agent, ciprofloxacin has been modified with a propylamine spacer and linked to two common bifunctional chelators, p-SCN-Bz-DOTA and p-SCN-Bz-NOTA. The two ciprofloxacin conjugates, CP-PA-SCN-Bz-DOTA (1) and CP-PA-SCN-Bz-NOTA (2), were radiolabeled with (68)Ga in >90% radiochemical yield and were moderately stable in vitro for 4 h. The efficacy of (68)Ga-1 and (68)Ga-2 has been investigated in vitro in Staphylococcus aureus cells where bacterial binding of the radiotracers (0.9-1.0% for (68)Ga-1 and 1.6-2.3% for (68)Ga-2) could not be blocked in the presence of excess amount of unlabeled ciprofloxacin. However, uptake of radiotracers in live bacterial cells was significantly higher (p < 0.01) than that in non-viable bacterial cells. Bacterial infection targeting efficacy of (68)Ga-1 and (68)Ga-2 was tested in vivo in rats where the infected muscle-to-inflamed muscle ((68)Ga-1: 2 ± 0.2, (68)Ga-2: 3 ± 0.5) and infected muscle-to-normal muscle ratios ((68)Ga-1: 3 ± 0.4, (68)Ga-2: 6.6 ± 0.8) were found to improve at 120 min p.i. Fast blood clearance and renal excretion was observed for both the radiotracers. The two (68)Ga-labeled infection targeting radiotracers could discriminate between bacterial infection and inflammation in vivo and are worthy of further detailed investigation as infection imaging agents at the clinical level.
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Affiliation(s)
- Drishty Satpati
- Radiopharmaceuticals Chemistry Section, Radiochemistry and Isotope Group, Bhabha Atomic Research Center, Mumbai, India
| | - Chanda Arjun
- Board of Radiation and Isotope Technology, Navi Mumbai, India
| | | | - Grace Samuel
- Board of Radiation and Isotope Technology, Navi Mumbai, India
| | - Sharmila Banerjee
- Radiopharmaceuticals Chemistry Section, Radiochemistry and Isotope Group, Bhabha Atomic Research Center, Mumbai, India
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Desbois N, Pacquelet S, Dubois A, Michelin C, Gros CP. Easy access to heterobimetallic complexes for medical imaging applications via microwave-enhanced cycloaddition. Beilstein J Org Chem 2015; 11:2202-8. [PMID: 26664643 PMCID: PMC4660971 DOI: 10.3762/bjoc.11.239] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2015] [Accepted: 10/25/2015] [Indexed: 12/12/2022] Open
Abstract
The Cu(I)-catalysed Huisgen cycloaddition, known as “click” reaction, has been applied to the synthesis of a range of triazole-linked porphyrin/corrole to DOTA/NOTA derivatives. Microwave irradiation significantly accelerates the reaction. The synthesis of heterobimetallic complexes was easily achieved in up to 60% isolated yield. Heterobimetallic complexes were easily prepared as potential MRI/PET (SPECT) bimodal contrast agents incorporating one metal (Mn, Gd) for the enhancement of contrast for MRI applications and one “cold” metal (Cu, Ga, In) for future radionuclear imaging applications. Preliminary relaxivity measurements showed that the reported complexes are promising contrast agents (CA) in MRI.
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Affiliation(s)
- Nicolas Desbois
- Université de Bourgogne Franche-Comté, ICMUB (UMR CNRS 6302), 9 Avenue Alain Savary, BP 47870, 21078 Dijon Cedex, France
| | - Sandrine Pacquelet
- Université de Bourgogne Franche-Comté, ICMUB (UMR CNRS 6302), 9 Avenue Alain Savary, BP 47870, 21078 Dijon Cedex, France
| | - Adrien Dubois
- Université de Bourgogne Franche-Comté, ICMUB (UMR CNRS 6302), 9 Avenue Alain Savary, BP 47870, 21078 Dijon Cedex, France
| | - Clément Michelin
- Université de Bourgogne Franche-Comté, ICMUB (UMR CNRS 6302), 9 Avenue Alain Savary, BP 47870, 21078 Dijon Cedex, France
| | - Claude P Gros
- Université de Bourgogne Franche-Comté, ICMUB (UMR CNRS 6302), 9 Avenue Alain Savary, BP 47870, 21078 Dijon Cedex, France
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24
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Lee JH, Kim H, Yao Z, Lee SJ, Szajek LP, Grasso L, Pastan I, Paik CH. Tumor and organ uptake of (64)Cu-labeled MORAb-009 (amatuximab), an anti-mesothelin antibody, by PET imaging and biodistribution studies. Nucl Med Biol 2015; 42:880-6. [PMID: 26307499 DOI: 10.1016/j.nucmedbio.2015.07.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Revised: 07/17/2015] [Accepted: 07/24/2015] [Indexed: 01/20/2023]
Abstract
OBJECTIVES To investigate the effect of the injection dose of MORAb-009 (amatuximab, an anti-mesothelin monoclonal antibody), the tumor size and the level of shed mesothelin on the uptake of the antibody in mesothelin-positive tumor and organs by biodistribution (BD) and positron emission tomography (PET) imaging studies. METHODS 2-S-(4-Isothiocyanatobenzyl)-1,4,7-triazacyclononane-1,4,7-triacetic acid (p-SCN-Bn-NOTA) was conjugated to amatuximab and labeled with (64)CuCl2 in 0.25 M acetate buffer, pH4.2. The resulting (64)Cu-NOTA-amatuximab was purified with a PD 10 column. To investigate the dose effect or the effect of tumor size, the BD was performed in groups of nude mice (n=5) with mesothelin-expressing A431/H9 tumors (range, 80-300 mm(3)) one day after iv injection of (64)Cu-NOTA-amatuximab (10 μCi) containing a total amatuximab dose of 2, 30, or 60 μg. The BD and PET imaging were also investigated 3, 24 and 48 h after injecting a total dose of 30 μg (10 μCi for BD), and 2 or 60 μg (300 μCi for PET), respectively. RESULTS Comparing the results of the BDs from three different injection doses, the major difference was shown in the uptake (%ID/g) of the radiolabel in tumor, liver and blood. The tumor uptake and blood retention from 30 and 60 μg doses were greater than those from 2 μg dose, whereas the liver uptake was smaller. The BD studies also demonstrated a positive correlation between tumor size (or the level of shed mesothelin in blood) and liver uptake. However, there was a negative correlation between tumor size (or the shed mesothelin level) and tumor uptake and between tumor size and blood retention. These findings were confirmed by the PET imaging study, which clearly visualized the tumor uptake with the radiolabel concentrated in the tumor core and produced a tumor to liver ratio of 1.2 at 24h post-injection with 60 μg amatuximab, whereas the injection of 2 μg amatuximab produced a tumor to liver ratio of 0.4 at 24h post-injection. CONCLUSION Our studies using a nude mouse model of A431/H9 tumor demonstrated that the injection of a high amatuximab dose (30 to 60 μg) could provide a beneficial effect in maximizing tumor uptake while maintaining minimum liver and spleen uptakes of the radiolabel, and in facilitating its penetration into the tumor core.
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Affiliation(s)
- Jae-Ho Lee
- Nuclear Medicine, Radiology and Imaging Sciences, Clinical Center, NIH, Bethesda, MD, 20892, USA.
| | - Heejung Kim
- Nuclear Medicine, Radiology and Imaging Sciences, Clinical Center, NIH, Bethesda, MD, 20892, USA
| | - Zhengsheng Yao
- Nuclear Medicine, Radiology and Imaging Sciences, Clinical Center, NIH, Bethesda, MD, 20892, USA
| | - Sung-Jin Lee
- Nuclear Medicine, Radiology and Imaging Sciences, Clinical Center, NIH, Bethesda, MD, 20892, USA
| | - Lawrence P Szajek
- Positron Emission Tomography Department, Clinical Center, NIH, Bethesda, MD, 20892, USA
| | | | - Ira Pastan
- Laboratory of Molecular Biology, NCI, NIH, Bethesda, MD, 20892, USA
| | - Chang H Paik
- Nuclear Medicine, Radiology and Imaging Sciences, Clinical Center, NIH, Bethesda, MD, 20892, USA.
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Lux J, White AG, Chan M, Anderson CJ, Almutairi A. Nanogels from metal-chelating crosslinkers as versatile platforms applied to copper-64 PET imaging of tumors and metastases. Am J Cancer Res 2015; 5:277-88. [PMID: 25553115 PMCID: PMC4279191 DOI: 10.7150/thno.10904] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2014] [Accepted: 12/03/2014] [Indexed: 12/13/2022] Open
Abstract
Metals are essential in medicine for both therapy and diagnosis. We recently created the first metal-chelating nanogel imaging agent, which employed versatile, reproducible chemistry that maximizes chelation stability. Here we demonstrate that our metal chelating crosslinked nanogel technology is a powerful platform by incorporating (64)Cu to obtain PET radiotracers. Polyacrylamide-based nanogels were crosslinked with three different polydentate ligands (DTPA, DOTA, NOTA). NOTA-based nanogels stably retained (64)Cu in mouse serum and accumulated in tumors in vivo as detected by PET/CT imaging. Measurement of radioactivity in major organs ex vivo confirmed this pattern, revealing a high accumulation (12.3% ID/g and 16.6% ID/g) in tumors at 24 and 48 h following administration, with lower accumulation in the liver (8.5% ID/g at 24 h) and spleen (5.5% ID/g). Nanogels accumulated even more efficiently in metastases (29.9% and 30.4% ID/g at 24 and 48 h). These metal-chelating nanogels hold great promise for future application as bimodal PET/MRI agents; chelation of β-emitting radionuclides could enable radiation therapy.
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Roosenburg S, Laverman P, Joosten L, Cooper MS, Kolenc-Peitl PK, Foster JM, Hudson C, Leyton J, Burnet J, Oyen WJG, Blower PJ, Mather SJ, Boerman OC, Sosabowski JK. PET and SPECT imaging of a radiolabeled minigastrin analogue conjugated with DOTA, NOTA, and NODAGA and labeled with (64)Cu, (68)Ga, and (111)In. Mol Pharm 2014; 11:3930-7. [PMID: 24992368 DOI: 10.1021/mp500283k] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Cholecystokinin-2 (CCK-2) receptors, overexpressed in cancer types such as small cell lung cancers (SCLC) and medullary thyroid carcinomas (MTC), may serve as targets for peptide receptor radionuclide imaging. A variety of CCK and gastrin analogues has been developed, but a major drawback is metabolic instability or high kidney uptake. The minigastrin analogue PP-F11 has previously been shown to be a promising peptide for imaging of CCK-2 receptor positive tumors and was therefore further evaluated. The peptide was conjugated with one of the macrocyclic chelators DOTA, NOTA, or NODAGA. The peptide conjugates were then radiolabeled with either (68)Ga, (64)Cu, or (111)In. All (radio)labeled compounds were evaluated in vitro (IC50) and in vivo (biodistribution and PET/CT and SPECT/CT imaging). IC50 values were in the low nanomolar range for all compounds (0.79-1.51 nM). In the biodistribution studies, (68)Ga- and (111)In-labeled peptides showed higher tumor-to-background ratios than the (64)Cu-labeled compounds. All tested radiolabeled compounds clearly visualized the CCK2 receptor positive tumor in PET or SPECT imaging. The chelator did not seem to affect in vivo behavior of the peptide for (111)In- and (68)Ga-labeled peptides. In contrast, the biodistribution of the (64)Cu-labeled peptides showed high uptake in the liver and in other organs, most likely caused by high blood levels, probably due to dissociation of (64)Cu from the chelator and subsequent transchelation to proteins. Based on the present study, (68)Ga-DOTA-PP-F11 might be a promising radiopharmaceutical for PET/CT imaging of CCK2 receptor expressing tumors such as MTC and SCLC. Clinical studies are warranted to investigate the potential of this tracer.
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Affiliation(s)
- S Roosenburg
- Department of Radiology and Nuclear Medicine, Radboud University Medical Center , 6500 HB Nijmegen, The Netherlands
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Su X, Cheng K, Jeon J, Shen B, Venturin GT, Hu X, Rao J, Chin FT, Wu H, Cheng Z. Comparison of two site-specifically (18)F-labeled affibodies for PET imaging of EGFR positive tumors. Mol Pharm 2014; 11:3947-56. [PMID: 24972326 PMCID: PMC4218868 DOI: 10.1021/mp5003043] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
![]()
The
epidermal growth factor receptor (EGFR) serves as an attractive target
for cancer molecular imaging and therapy. Our previous positron emission
tomography (PET) studies showed that the EGFR-targeting affibody molecules 64Cu-DOTA-ZEGFR:1907 and 18F-FBEM-ZEGFR:1907 can discriminate between high and low EGFR-expression
tumors and have the potential for patient selection for EGFR-targeted
therapy. Compared with 64Cu, 18F may improve
imaging of EGFR-expression and is more suitable for clinical application,
but the labeling reaction of 18F-FBEM-ZEGFR:1907 requires a long synthesis time. The aim of the present study is
to develop a new generation of 18F labeled affibody probes
(Al18F-NOTA-ZEGFR:1907 and 18F-CBT-ZEGFR:1907) and to determine whether they are suitable agents
for imaging of EGFR expression. The first approach consisted of conjugating
ZEGFR:1907 with NOTA and radiolabeling with Al18F to produce Al18F-NOTA-ZEGFR:1907. In a second
approach the prosthetic group 18F-labeled-2-cyanobenzothiazole
(18F-CBT) was conjugated to Cys-ZEGFR:1907 to
produce 18F-CBT-ZEGFR:1907. Binding affinity
and specificity of Al18F-NOTA-ZEGFR:1907 and 18F-CBT-ZEGFR:1907 to EGFR were evaluated using
A431 cells. Biodistribution and PET studies were conducted on mice
bearing A431 xenografts after injection of Al18F-NOTA-ZEGFR:1907 or 18F-CBT-ZEGFR:1907 with
or without coinjection of unlabeled affibody proteins. The radiosyntheses
of Al18F-NOTA-ZEGFR:1907 and 18F-CBT-ZEGFR:1907 were completed successfully within 40 and 120 min
with a decay-corrected yield of 15% and 41% using a 2-step, 1-pot
reaction and 2-step, 2-pot reaction, respectively. Both probes bound
to EGFR with low nanomolar affinity in A431 cells. Although 18F-CBT-ZEGFR:1907 showed instability in vivo, biodistribution studies revealed rapid and high tumor accumulation
and quick clearance from normal tissues except the bones. In contrast,
Al18F-NOTA-ZEGFR:1907 demonstrated high in vitro and in vivo stability, high tumor
uptake, and relative low uptake in most of the normal organs except
the liver and kidneys at 3 h after injection. The specificity of both
probes for A431 tumors was confirmed by their lower uptake on coinjection
of unlabeled affibody. PET studies showed that Al18F-NOTA-ZEGFR:1907 and 18F-CBT-ZEGFR:1907 could
clearly identify EGFR positive tumors with good contrast. Two strategies
for 18F-labeling of affibody molecules were successfully
developed as two model platforms using NOTA or CBT coupling to affibody
molecules that contain an N-terminal cysteine. Al18F-NOTA-ZEGFR:1907 and 18F-CBT-ZEGFR:1907 can
be reliably obtained in a relatively short time. Biodistribution and
PET studies demonstrated that Al18F-NOTA-ZEGFR:1907 is a promising PET probe for imaging EGFR expression in living mice.
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Affiliation(s)
- Xinhui Su
- Department of Nuclear Medicine, Zhongshan Hospital Xiamen University , Xiamen 361004, China
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Abstract
OBJECTIVE Colchicine, a plant-derived alkaloid, is a known substrate for P-glycoprotein (Pgp), which confers multidrug resistance (MDR) to cancer cells and tumors, through enhanced efflux of chemotherapeutic drugs. Hence, radiolabeled colchicine can be a suitable probe for imaging of activity of Pgp transport in vivo and early diagnosis of MDR. METHODS In the present study, colchicine was hydrolyzed to desacetylcolchiceine for conjugation with p-SCN-Bn-DOTA and p-SCN-Bn-NOTA. The resulting conjugates, DOTA-desacetylcolchiceine and NOTA-desacetylcolchiceine, were radiolabeled with 68Ga. The radiotracers 68Ga-DOTA-desacetylcolchiceine (68Ga-1) and 68Ga-NOTA-desacetylcolchiceine (68Ga-2) were evaluated in vitro (MCF-7 and T47D breast cancer cell lines) and in vivo (biodistribution studies, Swiss mice bearing fibrosarcoma tumors). RESULTS The radiotracers prepared in >97% radiochemical yield showed good in vitro binding and significant inhibition with 100-fold cold colchicine (p<0.05). In vivo the tumor uptake reached maximum at 120 minutes postinjection (68Ga-1: 2.35%±0.39% injected dose per gram [ID/g]; 68Ga-2: 1.5%±0.31% ID/g). Of the two radiotracers 68Ga-2 cleared faster from blood (p<0.05) with lower uptake in nontargeted organs as compared with 68Ga-1. CONCLUSIONS The radiotracer 68Ga-2 has shown improved pharmacokinetic features over 68Ga-1 and the previously reported 99mTc(CO)3-colchicine radiotracer. The preliminary studies with 68Ga-2 indicate its potential for in vivo targeting of tumor. However, the efficacy of the radiotracer for imaging of multidrug-resistant states will be ascertained in future.
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Affiliation(s)
- Drishty Satpati
- 1 Isotope Applications & Radiopharmaceuticals Division, Bhabha Atomic Research Center , Mumbai, India
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29
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Sin I, Kang CS, Bandara N, Sun X, Zhong Y, Rogers BE, Chong HS. Novel hexadentate and pentadentate chelators for ⁶⁴Cu-based targeted PET imaging. Bioorg Med Chem 2014; 22:2553-62. [PMID: 24657050 DOI: 10.1016/j.bmc.2014.02.041] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2013] [Revised: 02/10/2014] [Accepted: 02/19/2014] [Indexed: 11/26/2022]
Abstract
A series of new hexadentate and pentadentate chelators were designed and synthesized as chelators of (64)Cu. The new pentadentate and hexadentate chelators contain different types of donor groups and are expected to form neutral complexes with Cu(II). The new chelators were evaluated for complex kinetics and stability with (64)Cu. The new chelators instantly bound to (64)Cu with high labeling efficiency and maximum specific activity. All (64)Cu-radiolabeled complexes in human serum remained intact for 2 days. The (64)Cu-radiolabeled complexes were further challenged by EDTA in a 100-fold molar excess. Among the (64)Cu-radiolabeled complexes evaluated, (64)Cu-complex of the new chelator E was well tolerated with a minimal transfer of (64)Cu to EDTA. (64)Cu-radiolabeled complex of the new chelator E was further evaluated for biodistribution studies using mice and displayed rapid blood clearance and low organ uptake. (64)Cu-chelator E produced a favorable in vitro and in vivo complex stability profiles comparable to (64)Cu complex of the known hexadentate NOTA chelator. The in vitro and in vivo data highlight strong potential of the new chelator E for targeted PET imaging application.
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Affiliation(s)
- Inseok Sin
- Chemistry Division, Department of Biological and Chemical Sciences, Illinois Institute of Technology, 3101 S. Dearborn St., Chicago, IL 60616, United States
| | - Chi Soo Kang
- Chemistry Division, Department of Biological and Chemical Sciences, Illinois Institute of Technology, 3101 S. Dearborn St., Chicago, IL 60616, United States
| | - Nilantha Bandara
- Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, United States
| | - Xiang Sun
- Chemistry Division, Department of Biological and Chemical Sciences, Illinois Institute of Technology, 3101 S. Dearborn St., Chicago, IL 60616, United States
| | - Yongliang Zhong
- Chemistry Division, Department of Biological and Chemical Sciences, Illinois Institute of Technology, 3101 S. Dearborn St., Chicago, IL 60616, United States
| | - Buck E Rogers
- Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, United States; Department of Radiation Oncology, Washington University School of Medicine, St. Louis, MO 63110, United States
| | - Hyun-Soon Chong
- Chemistry Division, Department of Biological and Chemical Sciences, Illinois Institute of Technology, 3101 S. Dearborn St., Chicago, IL 60616, United States.
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30
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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] [What about the content of this article? (0)] [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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Shetty D, Lee YS, Jeong JM. (68)Ga-labeled radiopharmaceuticals for positron emission tomography. Nucl Med Mol Imaging 2010; 44:233-40. [PMID: 24899958 DOI: 10.1007/s13139-010-0056-6] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2010] [Accepted: 09/24/2010] [Indexed: 10/19/2022] Open
Abstract
(68)Ga is a promising emerging radionuclide for positron emission tomography (PET). It is produced using a (68)Ge/(68)Ga-generator, and thus, would enable the cyclotron-independent distribution of PET. However, new (68)Ga-labeled radiopharmaceuticals that can replace (18)F-labeled agents like [(18)F]fluorodeoxyglucose (FDG) are needed. Most of the (68)Ga-labeled derivatives currently used are peptide agents, but the developments of other agents, such as amino acid derivatives, nitroimidazole derivatives, and glycosylated human serum albumin, are being actively pursued in many laboratories. Thus, appearance of new (68)Ga-labeled radiopharmaceuticals with high impact are expected in the near future. Here, we present an overview of (68)Ga-labeled agents in terms of their clinical significances and relevances to the management of certain tumors, and pertinent pre-clinical developments.
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