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Xie T, Park JS, Zhuo W, Zaidi H. Development of a nonhuman primate computational phantom for radiation dosimetry. Med Phys 2019; 47:736-744. [DOI: 10.1002/mp.13936] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Revised: 11/01/2019] [Accepted: 11/13/2019] [Indexed: 01/27/2023] Open
Affiliation(s)
- Tianwu Xie
- Institute of Radiation Medicine Fudan University 2094 Xietu Road Shanghai 200032China
- Department of Medical Imaging and Information Sciences Geneva University Hospital Geneva Switzerland
| | - Jin Seo Park
- Department of Anatomy Dongguk University School of Medicine Gyeongju Korea
| | - Weihai Zhuo
- Institute of Radiation Medicine Fudan University 2094 Xietu Road Shanghai 200032China
| | - Habib Zaidi
- Department of Medical Imaging and Information Sciences Geneva University Hospital Geneva Switzerland
- Geneva Neuroscience Center Geneva University Geneva Switzerland
- Department of Nuclear Medicine and Molecular Imaging University of Groningen University Medical Center Groningen Groningen Netherlands
- Department of Nuclear Medicine University of Southern Denmark DK‐500Odense Denmark
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2
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Verwer EE, Kavanagh TR, Mischler WJ, Feng Y, Takahashi K, Wang S, Shoup TM, Neelamegam R, Yang J, Guehl NJ, Ran C, Massefski W, Cui Y, El-Chemaly S, Sadow PM, Oldham WM, Kijewski MF, El Fakhri G, Normandin MD, Priolo C. [ 18F]Fluorocholine and [ 18F]Fluoroacetate PET as Imaging Biomarkers to Assess Phosphatidylcholine and Mitochondrial Metabolism in Preclinical Models of TSC and LAM. Clin Cancer Res 2018; 24:5925-5938. [PMID: 30054282 DOI: 10.1158/1078-0432.ccr-17-3693] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Revised: 06/01/2018] [Accepted: 07/23/2018] [Indexed: 01/30/2023]
Abstract
PURPOSE Tuberous sclerosis complex (TSC) is an autosomal dominant disorder caused by inactivating mutations of the TSC1 or TSC2 gene, characterized by neurocognitive impairment and benign tumors of the brain, skin, heart, and kidneys. Lymphangioleiomyomatosis (LAM) is a diffuse proliferation of α-smooth muscle actin-positive cells associated with cystic destruction of the lung. LAM occurs almost exclusively in women, as a TSC manifestation or a sporadic disorder (TSC1/TSC2 somatic mutations). Biomarkers of whole-body tumor burden/activity and response to rapalogs or other therapies remain needed in TSC/LAM. EXPERIMENTAL DESIGN These preclinical studies aimed to assess feasibility of [18F]fluorocholine (FCH) and [18F]fluoroacetate (FACE) as TSC/LAM metabolic imaging biomarkers. RESULTS We previously reported that TSC2-deficient cells enhance phosphatidylcholine synthesis via the Kennedy pathway. Here, we show that TSC2-deficient cells exhibit rapid uptake of [18F]FCH in vivo and can be visualized by PET imaging in preclinical models of TSC/LAM, including subcutaneous tumors and pulmonary nodules. Treatment with rapamycin (72 hours) suppressed [18F]FCH standardized uptake value (SUV) by >50% in tumors. Interestingly, [18F]FCH-PET imaging of TSC2-deficient xenografts in ovariectomized mice also showed a significant decrease in tumor SUV. Finally, we found rapamycin-insensitive uptake of FACE by TSC2-deficient cells in vitro and in vivo, reflecting its mitochondrial accumulation via inhibition of aconitase, a TCA cycle enzyme. CONCLUSIONS Preclinical models of TSC2 deficiency represent informative platforms to identify tracers of potential clinical interest. Our findings provide mechanistic evidence for testing the potential of [18F]FCH and [18F]FACE as metabolic imaging biomarkers for TSC and LAM proliferative lesions, and novel insights into the metabolic reprogramming of TSC tumors.
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Affiliation(s)
- Eline E Verwer
- Gordon Center for Medical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Taylor R Kavanagh
- Pulmonary and Critical Care Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - William J Mischler
- Pulmonary and Critical Care Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - You Feng
- Pulmonary and Critical Care Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Kazue Takahashi
- Gordon Center for Medical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Shuyan Wang
- Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Timothy M Shoup
- Gordon Center for Medical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Ramesh Neelamegam
- Gordon Center for Medical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Jing Yang
- Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Nicolas J Guehl
- Gordon Center for Medical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Chongzhao Ran
- Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Walter Massefski
- Dana Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts
| | - Ye Cui
- Pulmonary and Critical Care Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Souheil El-Chemaly
- Pulmonary and Critical Care Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Peter M Sadow
- Department of Pathology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - William M Oldham
- Pulmonary and Critical Care Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Marie F Kijewski
- Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Georges El Fakhri
- Gordon Center for Medical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Marc D Normandin
- Gordon Center for Medical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Carmen Priolo
- Pulmonary and Critical Care Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts.
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3
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Abstract
The discovery of MLH1-rheMac hereditary nonpolyposis colorectal cancer syndrome in rhesus macaques (MLH1-rheMac HNPCC), which is an orthologue of Lynch syndrome in humans, is highly significant in the field of oncology. The hereditary nature of this disease should allow for planned cross-breeding of rhesus macaques to assess the effects of homozygous versus heterozygous MLH1 gene mutations, as well as other comutations and environmental factors that may affect the development of colon cancers. Also, the MLH1-rheMac HNPCC syndrome in rhesus macaques can serve as an important model for development of novel approaches to diagnosis and therapy of Lynch syndrome in human patients. Over the past two decades, 33 cases of colonic adenocarcinomas have been diagnosed in rhesus macaques (Macaca mulatta) at the nonhuman primate colony of the Keeling Center for Comparative Medicine and Research at The University of Texas MD Anderson Cancer Center. The distinctive feature in these cases, based on PET/computed tomography (CT) imaging, was the presence of two or three tumor lesions in different locations, including proximal to the ileocecal juncture, proximal to the hepatic flexure, and/or in the sigmoid colon. These colon carcinoma lesions selectively accumulated [18F]fluorodeoxyglucose ([18F]FDG) and [18F]fluoroacetate ([18F]FACE) at high levels, reflecting elevated carbohydrate and fatty acid metabolism in these tumors. In contrast, the accumulation of [18F]fluorothymidine ([18F]FLT) was less significant, reflecting slow proliferative activity in these tumors. The diagnoses of colon carcinomas were confirmed by endoscopy. The expression of MLH1, MSH2, and MSH6 proteins and the degree of microsatellite instability (MSI) was assessed in colon carcinomas. The loss of MLH1 protein expression was observed in all tumors and was associated with a deletion mutation in the MLH1 promoter region and/or multiple single-nucleotide polymorphism (SNP) mutations in the MLH1 gene. All tumors exhibited various degrees of MSI. The pedigree analysis of this rhesus macaque population revealed several clusters of affected animals related to each other over several generations, suggesting an autosomal dominant transmission of susceptibility for colon cancer. The newly discovered hereditary nonpolyposis colorectal cancer syndrome in rhesus macaques, termed MLH1-rheMac, may serve as a model for development of novel approaches to diagnosis and therapy of Lynch syndrome in humans.
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Eason CT. Connections between rodenticides and drugs: a review of natural compounds with ecological, biocidal and medical applications. NEW ZEALAND JOURNAL OF ZOOLOGY 2017. [DOI: 10.1080/03014223.2017.1348956] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Charles T. Eason
- Faculty of Agriculture and Life Sciences, Department of Ecology, Lincoln University, Lincoln, New Zealand
- Cawthron Institute, Nelson, New Zealand
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5
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Yamauchi H, Kagawa S, Kishibe Y, Takahashi M, Nishii R, Mizuma H, Takahashi K, Onoe H, Higashi T. Increase in [18F]-Fluoroacetate Uptake in Patients With Chronic Hemodynamic Cerebral Ischemia. Stroke 2015; 46:2669-72. [DOI: 10.1161/strokeaha.115.010080] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2015] [Accepted: 07/02/2015] [Indexed: 11/16/2022]
Abstract
Background and Purpose—
[18F]-fluoroacetate (
18
F-FACE) can be used for evaluating glial cell metabolism. Experimental studies have shown an increase in
18
F-FACE uptake in rodent models of cerebral ischemia. The aim of this study was to determine whether
18
F-FACE uptake is increased in the noninfarcted cerebral cortex in patients with hemodynamic ischemia owing to atherosclerotic internal carotid artery or middle cerebral artery disease.
Methods—
We evaluated 9 symptomatic patients with unilateral atherosclerotic internal carotid artery or middle cerebral artery disease and no cortical infarction using positron emission tomography with
18
F-FACE and
15
O-gases.
18
F-FACE uptake during 40 to 60 minutes after injection was compared with the cerebral blood flow, cerebral metabolic rate of oxygen, oxygen extraction fraction, and cerebral blood volume in the middle cerebral artery distributions.
Results—
Significant decreases of cerebral blood flow and cerebral metabolic rate of oxygen and increases of oxygen extraction fraction and cerebral blood volume were found in the hemisphere ipsilateral to the arterial lesion, and
18
F-FACE uptake in this region was greater than that in the contralateral hemisphere. The relative
18
F-FACE uptake (ipsilateral/contralateral ratio) was negatively correlated with cerebral blood flow or cerebral metabolic rate of oxygen values and was positively correlated with oxygen extraction fraction values. Multivariate analysis showed that the ipsilateral/contralateral
18
F-FACE uptake ratio was independently correlated with the cerebral blood flow (or oxygen extraction fraction) and cerebral metabolic rate of oxygen values.
Conclusions—
In patients with atherosclerotic internal carotid artery or middle cerebral artery disease,
18
F-FACE uptake is increased in the noninfarcted cerebral cortex with chronic hemodynamic ischemia characterized by misery perfusion with decreased oxygen metabolism. Increased
18
F-FACE uptake may indicate the cortical regions that are at particular risk for ischemic damage.
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Affiliation(s)
- Hiroshi Yamauchi
- From the Division of PET Imaging, Shiga Medical Centre Research Institute, Moriyama, Japan (H.Y., S.K., Y.K., M.T., T.H.); Department of Radiology, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan (R.N.); and Bio-Function Imaging Team (H.M., H.O.) and Clinical Application Unit (K.T.), RIKEN Center for Life Science Technologies, Kobe, Japan
| | - Shinya Kagawa
- From the Division of PET Imaging, Shiga Medical Centre Research Institute, Moriyama, Japan (H.Y., S.K., Y.K., M.T., T.H.); Department of Radiology, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan (R.N.); and Bio-Function Imaging Team (H.M., H.O.) and Clinical Application Unit (K.T.), RIKEN Center for Life Science Technologies, Kobe, Japan
| | - Yoshihiko Kishibe
- From the Division of PET Imaging, Shiga Medical Centre Research Institute, Moriyama, Japan (H.Y., S.K., Y.K., M.T., T.H.); Department of Radiology, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan (R.N.); and Bio-Function Imaging Team (H.M., H.O.) and Clinical Application Unit (K.T.), RIKEN Center for Life Science Technologies, Kobe, Japan
| | - Masaaki Takahashi
- From the Division of PET Imaging, Shiga Medical Centre Research Institute, Moriyama, Japan (H.Y., S.K., Y.K., M.T., T.H.); Department of Radiology, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan (R.N.); and Bio-Function Imaging Team (H.M., H.O.) and Clinical Application Unit (K.T.), RIKEN Center for Life Science Technologies, Kobe, Japan
| | - Ryuichi Nishii
- From the Division of PET Imaging, Shiga Medical Centre Research Institute, Moriyama, Japan (H.Y., S.K., Y.K., M.T., T.H.); Department of Radiology, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan (R.N.); and Bio-Function Imaging Team (H.M., H.O.) and Clinical Application Unit (K.T.), RIKEN Center for Life Science Technologies, Kobe, Japan
| | - Hiroshi Mizuma
- From the Division of PET Imaging, Shiga Medical Centre Research Institute, Moriyama, Japan (H.Y., S.K., Y.K., M.T., T.H.); Department of Radiology, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan (R.N.); and Bio-Function Imaging Team (H.M., H.O.) and Clinical Application Unit (K.T.), RIKEN Center for Life Science Technologies, Kobe, Japan
| | - Kazuhiro Takahashi
- From the Division of PET Imaging, Shiga Medical Centre Research Institute, Moriyama, Japan (H.Y., S.K., Y.K., M.T., T.H.); Department of Radiology, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan (R.N.); and Bio-Function Imaging Team (H.M., H.O.) and Clinical Application Unit (K.T.), RIKEN Center for Life Science Technologies, Kobe, Japan
| | - Hirotaka Onoe
- From the Division of PET Imaging, Shiga Medical Centre Research Institute, Moriyama, Japan (H.Y., S.K., Y.K., M.T., T.H.); Department of Radiology, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan (R.N.); and Bio-Function Imaging Team (H.M., H.O.) and Clinical Application Unit (K.T.), RIKEN Center for Life Science Technologies, Kobe, Japan
| | - Tatsuya Higashi
- From the Division of PET Imaging, Shiga Medical Centre Research Institute, Moriyama, Japan (H.Y., S.K., Y.K., M.T., T.H.); Department of Radiology, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan (R.N.); and Bio-Function Imaging Team (H.M., H.O.) and Clinical Application Unit (K.T.), RIKEN Center for Life Science Technologies, Kobe, Japan
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6
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Abstract
Positron emission tomography (PET) is an extraordinarily sensitive clinical imaging modality for interrogating tumor metabolism. Radiolabeled PET substrates can be traced at subphysiological concentrations, allowing noninvasive imaging of metabolism and intratumoral heterogeneity in systems ranging from advanced cancer models to patients in the clinic. There are a wide range of novel and more established PET radiotracers, which can be used to investigate various aspects of the tumor, including carbohydrate, amino acid, and fatty acid metabolism. In this review, we briefly discuss the more established metabolic tracers and describe recent work on the development of new tracers. Some of the unanswered questions in tumor metabolism are considered alongside new technical developments, such as combined PET/magnetic resonance imaging scanners, which could provide new imaging solutions to some of the outstanding diagnostic challenges facing modern cancer medicine.
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Affiliation(s)
- David Y. Lewis
- Cancer Research UK - Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Cambridge, UK
| | - Dmitry Soloviev
- Cancer Research UK - Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Cambridge, UK
| | - Kevin M. Brindle
- Cancer Research UK - Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Cambridge, UK
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7
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Ouyang Y, Tinianow JN, Cherry SR, Marik J. Evaluation of 2-[¹⁸F]fluoroacetate kinetics in rodent models of cerebral hypoxia-ischemia. J Cereb Blood Flow Metab 2014; 34:836-44. [PMID: 24517980 PMCID: PMC4013761 DOI: 10.1038/jcbfm.2014.22] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2013] [Accepted: 12/16/2013] [Indexed: 11/09/2022]
Abstract
Glia account for 90% of human brain cells and have a significant role in brain homeostasis. Thus, specific in vivo imaging markers of glial metabolism are potentially valuable. In the brain, 2-fluoroacetate is selectively taken up by glial cells and becomes metabolically trapped in the tricarboxylic acid cycle. Recent work in rodent brain injury models demonstrated elevated lesion uptake of 2-[(18)F]fluoroacetate ([(18)F]FACE), suggesting possible use for specifically imaging glial metabolism. To assess this hypothesis, we evaluated [(18)F]FACE kinetics in rodent models of cerebral hypoxia-ischemia at 3 and 24 hours post insult. Lesion uptake was significantly higher at 30 minutes post injection (P<0.05). An image-based method for input function estimation using cardiac blood was validated. Analysis of whole blood showed no significant metabolites and plasma activity concentrations of ∼50% that of whole blood. Kinetic models describing [(18)F]FACE uptake were developed and quantitatively compared. Elevated [(18)F]FACE uptake was found to be driven primarily by K₁/k₂ rather than k₃, but changes in the latter were detectable. The two-tissue irreversible uptake model (2T3k) was found to be necessary and sufficient for modeling [(18)F]FACE uptake. We conclude that kinetic modeling of [(18)F]FACE uptake represents a potentially useful tool for interrogation of glial metabolism.
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Affiliation(s)
- Yu Ouyang
- Department of Biomedical Engineering, University of California, Davis, California, USA
| | - Jeff N Tinianow
- Department of Biomedical Imaging, Genentech, Inc., South San Francisco, California, USA
| | - Simon R Cherry
- Department of Biomedical Engineering, University of California, Davis, California, USA
| | - Jan Marik
- Department of Biomedical Imaging, Genentech, Inc., South San Francisco, California, USA
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8
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Médran-Navarrete V, Bernards N, Kuhnast B, Damont A, Pottier G, Peyronneau MA, Kassiou M, Marguet F, Puech F, Boisgard R, Dollé F. [18F]DPA-C5yne, a novel fluorine-18-labelled analogue of DPA-714: radiosynthesis and preliminary evaluation as a radiotracer for imaging neuroinflammation with PET. J Labelled Comp Radiopharm 2014; 57:410-8. [PMID: 24764161 DOI: 10.1002/jlcr.3199] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2014] [Revised: 03/17/2014] [Accepted: 03/19/2014] [Indexed: 12/13/2022]
Abstract
DPA-C5yne, the lead compound of a novel series of DPA-714 derivatives in which the fluoroethoxy chain linked to the phenylpyrazolopyrimidine scaffold has been replaced by a fluoroalkyn-1-yl moiety, is a high affinity (Ki : 0.35 nM) and selective ligand targeting the translocator protein 18 kDa. In the present work, DPA-C5yne was labelled with no-carrier-added [(18)F]fluoride based on a one-step tosyloxy-for-fluorine nucleophilic substitution reaction, purified by cartridge and HPLC, and formulated as an i.v. injectable solution using a TRACERLab FX N Pro synthesizer. Typically, 4.3-5.2 GBq of [(18)F]DPA-C5yne, ready-to-use, chemically and radiochemically pure (> 95%), was obtained with specific radioactivities ranging from 55 to 110 GBq/µmol within 50-60 min, starting from a 30 GBq [(18)F]fluoride batch (14-17%). LogP and LogD of [(18)F]DPA-C5yne were measured using the shake-flask method and values of 2.39 and 2.51 were found, respectively. Autoradiography studies performed on slices of ((R,S)-α-amino-3-hydroxy-5-methyl-4-isoxazolopropionique (AMPA)-lesioned rat brains showed a high target-to-background ratio (1.9 ± 0.3). Selectivity and specificity of the binding for the translocator protein was demonstrated using DPA-C5yne (unlabelled), PK11195 and Flumazenil (central benzodiazepine receptor ligand) as competitors. Furthermore, DPA-C5yne proved to be stable in plasma at 37°C for at least 90 min.
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9
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Wyffels L, Thomae D, Waldron AM, Fissers J, Dedeurwaerdere S, Van der Veken P, Joossens J, Stroobants S, Augustyns K, Staelens S. In vivo evaluation of (18)F-labeled TCO for pre-targeted PET imaging in the brain. Nucl Med Biol 2014; 41:513-23. [PMID: 24768149 DOI: 10.1016/j.nucmedbio.2014.03.023] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Revised: 03/18/2014] [Accepted: 03/27/2014] [Indexed: 10/25/2022]
Abstract
INTRODUCTION The tetrazine-trans-cylooctene cycloaddition using radiolabeled tetrazine or radiolabeled trans-cyclooctene (TCO) has been reported to be a very fast, selective and bioorthogonal reaction that could be useful for in vivo radiolabeling of molecules. We wanted to evaluate the in vivo biodistribution profile and brain uptake of (18)F-labeled TCO ([(18)F]TCO) to assess its potential for pre-targeted imaging in the brain. METHODS We evaluated the in vivo behavior of [(18)F]TCO via an ex vivo biodistribution study complemented by in vivo μPET imaging at 5, 30, 60, 90, 120 and 240 min post tracer injection. An in vivo metabolite study was performed at 5 min, 30 min and 120 min post [(18)F]TCO injection by RP-HPLC analysis of plasma and brain extracts. Incubation with human liver microsomes was performed to further evaluate the metabolite profile of the tracer. RESULTS μPET imaging and ex-vivo biodistribution revealed an high initial brain uptake of [(18)F]TCO (3.8%ID/g at 5 min pi) followed by a washout to 3.0%ID/g at 30 min pi. Subsequently the brain uptake increased again to 3.7%ID/g at 120 min pi followed by a slow washout until 240 min pi (2.9%ID/g). Autoradiography confirmed homogenous brain uptake. On the μPET images bone uptake became gradually visible after 120 min pi and was clearly visible at 240 min pi. The metabolite study revealed a fast metabolization of [(18)F]TCO in plasma and brain into three main polar radiometabolites. CONCLUSIONS Although [(18)F]TCO has previously been described to be a useful tracer for radiolabeling of tetrazine modified targeting molecules, our study indicates that its utility for in vivo chemistry and pre-targeted imaging will be limited. Although [(18)F]TCO clearly enters the brain, it is quickly metabolized with a non-specific accumulation of radioactivity in the brain and bone.
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Affiliation(s)
- Leonie Wyffels
- Molecular Imaging Center Antwerp, University of Antwerp, Antwerp, Belgium; University Hospital Antwerp, Department of Nuclear Medicine, Edegem, Belgium
| | - David Thomae
- Molecular Imaging Center Antwerp, University of Antwerp, Antwerp, Belgium; Laboratory of Medicinal Chemistry, University of Antwerp, Antwerp, Belgium
| | - Ann-Marie Waldron
- Molecular Imaging Center Antwerp, University of Antwerp, Antwerp, Belgium; Department of Translational Neurosciences, University of Antwerp, Belgium
| | - Jens Fissers
- Molecular Imaging Center Antwerp, University of Antwerp, Antwerp, Belgium; Laboratory of Medicinal Chemistry, University of Antwerp, Antwerp, Belgium
| | | | | | - Jurgen Joossens
- Laboratory of Medicinal Chemistry, University of Antwerp, Antwerp, Belgium
| | - Sigrid Stroobants
- Molecular Imaging Center Antwerp, University of Antwerp, Antwerp, Belgium; University Hospital Antwerp, Department of Nuclear Medicine, Edegem, Belgium
| | - Koen Augustyns
- Laboratory of Medicinal Chemistry, University of Antwerp, Antwerp, Belgium
| | - Steven Staelens
- Molecular Imaging Center Antwerp, University of Antwerp, Antwerp, Belgium.
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10
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Takemoto K, Hatano E, Nishii R, Kagawa S, Kishibe Y, Takahashi M, Yamauchi H, Matsumura K, Zaima M, Toriguchi K, Tanabe K, Kitamura K, Seo S, Taura K, Endo K, Uemoto S, Higashi T. Assessment of [(18)F]-fluoroacetate PET/CT as a tumor-imaging modality: preclinical study in healthy volunteers and clinical evaluation in patients with liver tumor. Ann Nucl Med 2014; 28:371-80. [PMID: 24599824 DOI: 10.1007/s12149-014-0823-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2013] [Accepted: 02/05/2014] [Indexed: 11/30/2022]
Abstract
OBJECTIVE Although [(18)F]-FDG is a useful oncologic PET tracer, FDG uptake is known to be low in a certain type of hepatocellular carcinoma (HCC). [(18)F]-fluoroacetate ((18)F-FACE) is an [(18)F] fluorinated acetate, which is known to be converted into fatty acids, incorporated in membrane and is expected to be a promising oncologic PET tracer. The aim of this study was to evaluate the usefulness of (18)F-FACE as an oncologic PET tracer in preclinical study in healthy volunteers and in patients with liver tumors. METHODS Twenty-four healthy volunteers (age 48.2 ± 12.9 years old; 15 male and 9 female) and ten patients with liver tumor (age 72.1 ± 7.0 years old; 6 male and 4 female) were included. We performed whole-body static PET/CT scan using (18)F-FACE (n = 34) and (18)F-FDG (n = 5 for volunteers, n = 8 for patients) on each day, respectively. Qualitative analysis and quantitative analysis of tumors (5 HCCs, 1 cholangiocellular carcinoma, 4 metastatic tumors from colon cancer and P-NET) were performed using SUVmax and tumor-to-normal liver ratio (TNR). RESULTS In healthy volunteers, (18)F-FACE was metabolically stable in vivo and its biodistribution was almost similar to blood pool, basically uniformly independent of age and gender during PET scan time (up to 3 h). Normal physiological uptake of (18)F-FACE at each organ including liver (SUVmean 1.8 ± 0.2) was lower than that of blood pool (SUVmean 2.3 ± 0.3) at 1 h after injection. Chronic inflammatory uptake around femur of post-operative state of femoral osteotomy and faint uptake of benign hemangioma were observed in a case of healthy volunteer. (18)F-FACE (SUVmax 2.7 ± 0.6, TNR 1.5 ± 0.4) of liver tumors was significantly lower than those of (18)F-FDG uptake (6.5 ± 4.2, 2.6 ± 1.7, respectively). In qualitative analysis, (18)F-FDG was positive in 4 tumors (3 HCCs, 1 CCC) and negative in the other 6 tumors, while (18)F-FACE was also positive in 4 tumors which were the same tumors with positive (18)F-FDG uptake. CONCLUSIONS Biodistribution of (18)F-FACE was appropriate for oncologic imaging. Tumor (18)F-FACE uptake was positive in four patients with HCC and CCC, but the uptake pattern was similar to (18)F-FDG. Further evaluation was needed.
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Affiliation(s)
- Kenji Takemoto
- Department of Surgery, Graduate School of Medicine, Kyoto University, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, 6068507, Japan
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11
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Affiliation(s)
- Lucia G Le Roux
- Department of Cancer Systems Imaging, University of Texas MD Anderson Cancer Center, Houston, TX; Department of Diagnostic Radiology, University of Texas MD Anderson Cancer Center, Houston, TX
| | - Dawid Schellingerhout
- Department of Cancer Systems Imaging, University of Texas MD Anderson Cancer Center, Houston, TX; Department of Diagnostic Radiology, University of Texas MD Anderson Cancer Center, Houston, TX.
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12
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In vivo imaging in NHP models of malaria: challenges, progress and outlooks. Parasitol Int 2013; 63:206-15. [PMID: 24042056 PMCID: PMC7108422 DOI: 10.1016/j.parint.2013.09.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2012] [Revised: 08/30/2013] [Accepted: 09/06/2013] [Indexed: 12/22/2022]
Abstract
Animal models of malaria, mainly mice, have made a large contribution to our knowledge of host-pathogen interactions and immune responses, and to drug and vaccine design. Non-human primate (NHP) models for malaria are admittedly under-used, although they are probably closer models than mice for human malaria; in particular, NHP models allow the use of human pathogens (Plasmodium falciparum, Plasmodium vivax, Plasmodium malariae and Plasmodium knowlesi). NHPs, whether natural hosts or experimentally challenged with a simian Plasmodium, can also serve as robust pre-clinical models. Some simian parasites are closely related to a human counterpart, with which they may share a common ancestor, and display similar major features with the human infection and pathology. NHP models allow longitudinal studies, from the early events following sporozoite inoculation to the later events, including analysis of organs and tissues, particularly liver, spleen, brain and bone marrow. NHP models have one other significant advantage over mouse models: NHPs are our closest relatives and thus their biology is very similar to ours. Recently developed in vivo imaging tools have provided insight into malaria parasite infection and disease in mouse models. One advantage of these tools is that they limit the need for invasive procedures, such as tissue biopsies. Many such technologies are now available for NHP studies and provide new opportunities for elucidating host/parasite interactions. The aim of this review is to bring the malaria community up to date on what is currently possible and what soon will be, in terms of in vivo imaging in NHP models of malaria, to consider the pros and the cons of the various techniques, and to identify challenges.
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Peyronneau MA, Saba W, Goutal S, Damont A, Dollé F, Kassiou M, Bottlaender M, Valette H. Metabolism and quantification of [(18)F]DPA-714, a new TSPO positron emission tomography radioligand. Drug Metab Dispos 2013; 41:122-31. [PMID: 23065531 DOI: 10.1124/dmd.112.046342] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
[(18)F]DPA-714 [N,N-diethyl-2-(2-(4-(2[(18)F]-fluoroethoxy)phenyl)5,7dimethylpyrazolo[1,5a]pyrimidin-3-yl)acetamide] is a new radioligand currently used for imaging the 18-kDa translocator protein in animal models of neuroinflammation and recently in humans. The biodistribution by positron emission tomography (PET) in baboons and the in vitro and in vivo metabolism of [(18)F]DPA-714 were investigated in rats, baboons, and humans. Whole-body PET experiments showed a high uptake of radioactivity in the kidneys, heart, liver, and gallbladder. The liver was a major route of elimination of [(18)F]DPA-714, and urine was a route of excretion for radiometabolites. In rat and baboon plasma, high-performance liquid chromatography (HPLC) metabolic profiles showed three major radiometabolites accounting for 85% and 89% of total radioactivity at 120 minutes after injection, respectively. Rat microsomal incubations and analyses by liquid chromatography-mass spectrometry (LC-MS) identified seven metabolites, characterized as O-deethyl, hydroxyl, and N-deethyl derivatives of nonradioactive DPA-714, two of them having the same retention times than those detected in rat and baboon plasma. The third plasma radiometabolite was suggested to be a carboxylic acid compound that accounted for 15% of the rat brain radioactivity. O-deethylation led to a nonradioactive compound and [(18)F]fluoroacetic acid. Human CYP3A4 and CYP2D6 were shown to be involved in the oxidation of the radioligand. Finally an easy, rapid, and accurate method--indispensable for PET quantitative clinical studies--for quantifying [(18)F]DPA-714 by solid-phase extraction was developed. In vivo, an extensive metabolism of [(18)F]DPA-714 was observed in rats and baboons, identified as [(18)F]deethyl, [(18)F]hydroxyl, and [(18)F]carboxylic acid derivatives of [(18)F]DPA-714. The main route of excretion of the unchanged radioligand in baboons was hepatobiliary while that of radiometabolites was the urinary system.
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Affiliation(s)
- Marie-Anne Peyronneau
- CEA, DSV, I2BM, Service Hospitalier Frédéric Joliot, 4 Place du Général Leclerc, 91406 Orsay, France.
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Pisaneschi F, Witney TH, Iddon L, Aboagye EO. Synthesis of [18F]fluoro-pivalic acid: an improved PET imaging probe for the fatty acid synthesis pathway in tumours. MEDCHEMCOMM 2013. [DOI: 10.1039/c3md00169e] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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15
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Yeh HH, Tian M, Hinz R, Young D, Shavrin A, Mukhapadhyay U, Flores LG, Balatoni J, Soghomonyan S, Jeong HJ, Pal A, Uthamanthil R, Jackson JN, Nishii R, Mizuma H, Onoe H, Kagawa S, Higashi T, Fukumitsu N, Alauddin M, Tong W, Herholz K, Gelovani JG. Imaging epigenetic regulation by histone deacetylases in the brain using PET/MRI with ¹⁸F-FAHA. Neuroimage 2012; 64:630-9. [PMID: 22995777 DOI: 10.1016/j.neuroimage.2012.09.019] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2012] [Revised: 08/31/2012] [Accepted: 09/05/2012] [Indexed: 01/12/2023] Open
Abstract
Epigenetic modifications mediated by histone deacetylases (HDACs) play important roles in the mechanisms of different neurologic diseases and HDAC inhibitors (HDACIs) have shown promise in therapy. However, pharmacodynamic profiles of many HDACIs in the brain remain largely unknown due to the lack of validated methods for noninvasive imaging of HDAC expression-activity. In this study, dynamic PET/CT imaging was performed in 4 rhesus macaques using [(18)F]FAHA, a novel HDAC substrate, and [(18)F]fluoroacetate, the major radio-metabolite of [(18)F]FAHA, and fused with corresponding MR images of the brain. Quantification of [(18)F]FAHA accumulation in the brain was performed using a customized dual-tracer pharmacokinetic model. Immunohistochemical analyses of brain tissue revealed the heterogeneity of expression of individual HDACs in different brain structures and cell types and confirmed that PET/CT/MRI with [(18)F]FAHA reflects the level of expression-activity of HDAC class IIa enzymes. Furthermore, PET/CT/MRI with [(18)F]FAHA enabled non-invasive, quantitative assessment of pharmacodynamics of HDAC inhibitor SAHA in the brain.
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Affiliation(s)
- Hsin-Hsien Yeh
- Department of Experimental Diagnostic Imaging, University of Texas MD Anderson Cancer Center, Houston, Texas 77030, USA
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Alauddin MM. Positron emission tomography (PET) imaging with (18)F-based radiotracers. AMERICAN JOURNAL OF NUCLEAR MEDICINE AND MOLECULAR IMAGING 2011; 2:55-76. [PMID: 23133802 PMCID: PMC3478111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Received: 09/27/2011] [Accepted: 10/27/2011] [Indexed: 06/01/2023]
Abstract
Positron Emission Tomography (PET) is a nuclear medicine imaging technique that is widely used in early detection and treatment follow up of many diseases, including cancer. This modality requires positron-emitting isotope labeled biomolecules, which are synthesized prior to perform imaging studies. Fluorine-18 is one of the several isotopes of fluorine that is routinely used in radiolabeling of biomolecules for PET; because of its positron emitting property and favorable half-life of 109.8 min. The biologically active molecule most commonly used for PET is 2-deoxy-2-(18)F-fluoro-β-D-glucose ((18)F-FDG), an analogue of glucose, for early detection of tumors. The concentrations of tracer accumulation (PET image) demonstrate the metabolic activity of tissues in terms of regional glucose metabolism and accumulation. Other tracers are also used in PET to image the tissue concentration. In this review, information on fluorination and radiofluorination reactions, radiofluorinating agents, and radiolabeling of various compounds and their application in PET imaging is presented.
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Affiliation(s)
- Mian M Alauddin
- Department of Experimental Diagnostic Imaging, The University of Texas MD Anderson Cancer Center Houston, TX 77030, USA
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