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Zhu J, Pan F, Cai H, Pan L, Li Y, Li L, Li Y, Wu X, Fan H. Positron emission tomography imaging of lung cancer: An overview of alternative positron emission tomography tracers beyond F18 fluorodeoxyglucose. Front Med (Lausanne) 2022; 9:945602. [PMID: 36275809 PMCID: PMC9581209 DOI: 10.3389/fmed.2022.945602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Accepted: 08/31/2022] [Indexed: 11/13/2022] Open
Abstract
Lung cancer has been the leading cause of cancer-related mortality in China in recent decades. Positron emission tomography-computer tomography (PET/CT) has been established in the diagnosis of lung cancer. 18F-FDG is the most widely used PET tracer in foci diagnosis, tumor staging, treatment planning, and prognosis assessment by monitoring abnormally exuberant glucose metabolism in tumors. However, with the increasing knowledge on tumor heterogeneity and biological characteristics in lung cancer, a variety of novel radiotracers beyond 18F-FDG for PET imaging have been developed. For example, PET tracers that target cellular proliferation, amino acid metabolism and transportation, tumor hypoxia, angiogenesis, pulmonary NETs and other targets, such as tyrosine kinases and cancer-associated fibroblasts, have been reported, evaluated in animal models or under clinical investigations in recent years and play increasing roles in lung cancer diagnosis. Thus, we perform a comprehensive literature review of the radiopharmaceuticals and recent progress in PET tracers for the study of lung cancer biological characteristics beyond glucose metabolism.
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Affiliation(s)
- Jing Zhu
- Department of Respiratory and Critical Care Medicine, West China Hospital, Sichuan University, Chengdu, China,Respiratory and Critical Care Medicine, Mianyang Central Hospital, School of Medicine, University of Electronic Science and Technology of China, Mianyang, China,NHC Key Laboratory of Nuclear Technology Medical Transformation, Mianyang Central Hospital, School of Medicine, University of Electronic Science and Technology of China, Mianyang, China
| | - Fei Pan
- Department of Nuclear Medicine, Laboratory of Clinical Nuclear Medicine, West China Hospital, Sichuan University, Chengdu, China
| | - Huawei Cai
- Department of Nuclear Medicine, Laboratory of Clinical Nuclear Medicine, West China Hospital, Sichuan University, Chengdu, China
| | - Lili Pan
- Department of Nuclear Medicine, Laboratory of Clinical Nuclear Medicine, West China Hospital, Sichuan University, Chengdu, China
| | - Yalun Li
- Department of Respiratory and Critical Care Medicine, West China Hospital, Sichuan University, Chengdu, China
| | - Lin Li
- Department of Nuclear Medicine, Laboratory of Clinical Nuclear Medicine, West China Hospital, Sichuan University, Chengdu, China
| | - YunChun Li
- Department of Nuclear Medicine, Laboratory of Clinical Nuclear Medicine, West China Hospital, Sichuan University, Chengdu, China,Department of Nuclear Medicine, The Second People’s Hospital of Yibin, Yibin, China
| | - Xiaoai Wu
- Department of Nuclear Medicine, Laboratory of Clinical Nuclear Medicine, West China Hospital, Sichuan University, Chengdu, China,Xiaoai Wu,
| | - Hong Fan
- Department of Respiratory and Critical Care Medicine, West China Hospital, Sichuan University, Chengdu, China,*Correspondence: Hong Fan,
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Ciaffaglione V, Waghorn PA, Exner RM, Cortezon-Tamarit F, Godfrey SP, Sarpaki S, Quilter H, Dondi R, Ge H, Kociok-Kohn G, Botchway SW, Eggleston IM, Dilworth JR, Pascu SI. Structural Investigations, Cellular Imaging, and Radiolabeling of Neutral, Polycationic, and Polyanionic Functional Metalloporphyrin Conjugates. Bioconjug Chem 2021; 32:1374-1392. [PMID: 33525868 PMCID: PMC8299459 DOI: 10.1021/acs.bioconjchem.0c00691] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
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Over the past decade,
porphyrin derivatives have emerged as invaluable
synthetic building blocks and theranostic kits for the delivery of
cellular fluorescence imaging and photodynamic therapy. Tetraphenylporphyrin
(TPP), its metal complexes, and related derivatives have been investigated
for their use as dyes in histology and as components of multimodal
imaging probes. The photophysical properties of porphyrin–metal
complexes featuring radiometals have been a focus of our attention
for the realization of fluorescence imaging probes coupled with radioimaging
capabilities and therapeutic potential having “true”
theranostic promise. We report hereby on the synthesis, radiochemistry,
structural investigations, and preliminary in vitro and in vivo uptake studies on a range of functionalized
porphyrin-based derivatives. In pursuit of developing new porphyrin-based
probes for multimodality imaging applications, we report new functionalized
neutral, polycationic, and polyanionic porphyrins incorporating nitroimidazole
and sulfonamide moieties, which were used as targeting groups to improve
the notoriously poor pharmacokinetics of porphyrin tags. The resulting
functional metalloporphyrin species were stable under serum challenges
and the nitroimidazole and sulfonamide derivatives remained fluorescent,
allowing in vitro confocal studies and visualization
of the lysosomal uptake in a gallium(III) sulfonamide derivative.
The molecular structures of selected porphyrin derivatives were determined
by single crystal X-ray diffraction using synchrotron radiation. We
also investigated the nature of the emission/excitation behavior of
model functional porphyrins using in silico approaches
such as TD DFT in simple solvation models. The conjugation of porphyrins
with the [7-13] and [7-14] fragments of bombesin was also achieved,
to provide targeting of the gastrin releasing peptide receptor (GRPR).
Depending on the metal, probe conjugates of relevance for single photon
emission computed tomography (SPECT) or positron emission tomography
(PET) probes have been designed and tested hereby, using TPP and related
functional free base porphyrins as the bifunctional chelator synthetic
scaffold and 111In[In] or 68Ga[Ga], respectively,
as the central metal ions. Interestingly, for simple porphyrin conjugates
good radiochemical incorporation was obtained for both radiometals,
but the presence of peptides significantly diminished the radio-incorporation
yields. Although the gallium-68 radiochemistry of the bombesin conjugates
did not show radiochemical incorporation suitable for in vivo studies, likely because the presence of the peptide changed the
behavior of the TPP-NH2 synthon taken alone, the optical
imaging assays indicated that the conjugated peptide tags do mediate
uptake of the porphyrin units into cells.
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Affiliation(s)
- Valeria Ciaffaglione
- Department of Chemistry, University of Bath, Claverton Down, Bath, BA2 7AY, United Kingdom
| | - Philip A Waghorn
- Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA, United Kingdom
| | - Rüdiger M Exner
- Department of Chemistry, University of Bath, Claverton Down, Bath, BA2 7AY, United Kingdom
| | | | - Samuel P Godfrey
- Department of Chemistry, University of Bath, Claverton Down, Bath, BA2 7AY, United Kingdom
| | - Sophia Sarpaki
- Department of Chemistry, University of Bath, Claverton Down, Bath, BA2 7AY, United Kingdom
| | - Helena Quilter
- Department of Chemistry, University of Bath, Claverton Down, Bath, BA2 7AY, United Kingdom.,Department of Pharmacy and Pharmacology, University of Bath, Claverton Down, Bath, BA2 7AY, United Kingdom.,Centre for Sustainable and Circular Technologies, University of Bath, Bath, BA2 7AY, United Kingdom
| | - Ruggero Dondi
- Department of Pharmacy and Pharmacology, University of Bath, Claverton Down, Bath, BA2 7AY, United Kingdom
| | - Haobo Ge
- Department of Chemistry, University of Bath, Claverton Down, Bath, BA2 7AY, United Kingdom
| | - Gabriele Kociok-Kohn
- Department of Chemistry, University of Bath, Claverton Down, Bath, BA2 7AY, United Kingdom.,Material and Chemical Characterisation (MC2), University of Bath, Bath, BA2 7AY, United Kingdom
| | - Stanley W Botchway
- Research Complex at Harwell, STFC Rutherford Appleton Laboratory, Harwell Oxford, Didcot, OX11 0QX, United Kingdom
| | - Ian M Eggleston
- Department of Pharmacy and Pharmacology, University of Bath, Claverton Down, Bath, BA2 7AY, United Kingdom
| | - Jonathan R Dilworth
- Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA, United Kingdom
| | - Sofia I Pascu
- Department of Chemistry, University of Bath, Claverton Down, Bath, BA2 7AY, United Kingdom.,Centre for Sustainable and Circular Technologies, University of Bath, Bath, BA2 7AY, United Kingdom
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3
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Riccardi C, Napolitano E, Platella C, Musumeci D, Melone MAB, Montesarchio D. Anti-VEGF DNA-based aptamers in cancer therapeutics and diagnostics. Med Res Rev 2020; 41:464-506. [PMID: 33038031 DOI: 10.1002/med.21737] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 09/12/2020] [Accepted: 09/23/2020] [Indexed: 12/13/2022]
Abstract
The vascular endothelial growth factor (VEGF) family and its receptors play fundamental roles not only in physiological but also in pathological angiogenesis, characteristic of cancer progression. Aiming at finding putative treatments for several malignancies, various small molecules, antibodies, or protein-based drugs have been evaluated in vitro and in vivo as VEGF inhibitors, providing efficient agents approved for clinical use. Due to the high clinical importance of VEGF, also a great number of anti-VEGF nucleic acid-based aptamers-that is, oligonucleotides able to bind with high affinity and specificity a selected biological target-have been developed as promising agents in anticancer strategies. Notable research efforts have been made in optimization processes of the identified aptamers, searching for increased target affinity and/or bioactivity by exploring structural analogues of the lead compounds. This review is focused on recent studies devoted to the development of DNA-based aptamers designed to target VEGF. Their therapeutic potential as well as their significance in the construction of highly selective biosensors is here discussed.
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Affiliation(s)
- Claudia Riccardi
- Department of Chemical Sciences, University of Naples Federico II, Naples, Italy.,Department of Advanced Medical and Surgical Sciences, 2nd Division of Neurology, Center for Rare Diseases and Inter-University Center for Research in Neurosciences, University of Campania Luigi Vanvitelli, Naples, Italy
| | - Ettore Napolitano
- Department of Chemical Sciences, University of Naples Federico II, Naples, Italy
| | - Chiara Platella
- Department of Chemical Sciences, University of Naples Federico II, Naples, Italy
| | - Domenica Musumeci
- Department of Chemical Sciences, University of Naples Federico II, Naples, Italy.,Institute of Biostructures and Bioimages, Naples, Italy
| | - Mariarosa A B Melone
- Department of Advanced Medical and Surgical Sciences, 2nd Division of Neurology, Center for Rare Diseases and Inter-University Center for Research in Neurosciences, University of Campania Luigi Vanvitelli, Naples, Italy.,Sbarro Institute for Cancer Research and Molecular Medicine, Temple University, Philadelphia, Pennsylvania, USA
| | - Daniela Montesarchio
- Department of Chemical Sciences, University of Naples Federico II, Naples, Italy
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Kuchar M, Neuber C, Belter B, Bergmann R, Lenk J, Wodtke R, Kniess T, Steinbach J, Pietzsch J, Löser R. Evaluation of Fluorine-18-Labeled α1(I)-N-Telopeptide Analogs as Substrate-Based Radiotracers for PET Imaging of Melanoma-Associated Lysyl Oxidase. Front Chem 2018; 6:121. [PMID: 29755969 PMCID: PMC5932954 DOI: 10.3389/fchem.2018.00121] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Accepted: 03/30/2018] [Indexed: 12/28/2022] Open
Abstract
Accumulating evidence suggests an unequivocal role of lysyl oxidases as key players of tumor progression and metastasis, which renders this enzyme family highly attractive for targeted non-invasive functional imaging of tumors. Considering their function in matrix remodeling, malignant melanoma appears as particularly interesting neoplasia in this respect. For the development of radiotracers that enable PET imaging of the melanoma-associated lysyl oxidase activity, substrates derived from the type I collagen α1 N-telopeptide were labeled with fluorine-18 using N-succinimidyl 4-[18F]fluorobenzoate ([18F]SFB) as prosthetic reagent. With regards to potential crosslinking to tumor-associated collagen in vivo, their interaction with triple-helical type I collagen was studied by SPR. A mouse model of human melanoma was established on the basis of the A375 cell line, for which the expression of the oncologically relevant lysyl oxidase isoforms LOX and LOXL2 was demonstrated in Western blot and immunohistochemical experiments. The radiopharmacological profiles of the peptidic radiotracers were evaluated in normal rats and A375 melanoma-bearing mice by ex vivo metabolite analysis, whole-body biodistribution studies and dynamic PET imaging. Out of three 18F-labeled telopeptide analogs, the one with the most favorable substrate properties has shown favorable tumor uptake and tumor-to-muscle ratio. Lysyl oxidase-mediated tumor uptake was proven by pharmacological inhibition using β-aminopropionitrile and by employing negative-control analogs of impeded or abolished targeting capability. The latter were obtained by substituting the lysine residue by ornithine and norleucine, respectively. Comparing the tumor uptake of the lysine-containing peptide with that of the non-functional analogs indicate the feasibility of lysyl oxidase imaging in melanoma using substrate-based radiotracers.
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Affiliation(s)
- Manuela Kuchar
- Helmholtz-Zentrum Dresden Rossendorf, Institute of Radiopharmaceutical Cancer Research, Dresden, Germany.,Faculty of Chemistry and Food Chemistry, School of Science, Technische Unversität Dresden, Dresden, Germany
| | - Christin Neuber
- Helmholtz-Zentrum Dresden Rossendorf, Institute of Radiopharmaceutical Cancer Research, Dresden, Germany
| | - Birgit Belter
- Helmholtz-Zentrum Dresden Rossendorf, Institute of Radiopharmaceutical Cancer Research, Dresden, Germany
| | - Ralf Bergmann
- Helmholtz-Zentrum Dresden Rossendorf, Institute of Radiopharmaceutical Cancer Research, Dresden, Germany
| | - Jens Lenk
- Helmholtz-Zentrum Dresden Rossendorf, Institute of Radiopharmaceutical Cancer Research, Dresden, Germany.,Faculty of Chemistry and Food Chemistry, School of Science, Technische Unversität Dresden, Dresden, Germany
| | - Robert Wodtke
- Helmholtz-Zentrum Dresden Rossendorf, Institute of Radiopharmaceutical Cancer Research, Dresden, Germany.,Faculty of Chemistry and Food Chemistry, School of Science, Technische Unversität Dresden, Dresden, Germany
| | - Torsten Kniess
- Helmholtz-Zentrum Dresden Rossendorf, Institute of Radiopharmaceutical Cancer Research, Dresden, Germany
| | - Jörg Steinbach
- Helmholtz-Zentrum Dresden Rossendorf, Institute of Radiopharmaceutical Cancer Research, Dresden, Germany.,Faculty of Chemistry and Food Chemistry, School of Science, Technische Unversität Dresden, Dresden, Germany
| | - Jens Pietzsch
- Helmholtz-Zentrum Dresden Rossendorf, Institute of Radiopharmaceutical Cancer Research, Dresden, Germany.,Faculty of Chemistry and Food Chemistry, School of Science, Technische Unversität Dresden, Dresden, Germany
| | - Reik Löser
- Helmholtz-Zentrum Dresden Rossendorf, Institute of Radiopharmaceutical Cancer Research, Dresden, Germany.,Faculty of Chemistry and Food Chemistry, School of Science, Technische Unversität Dresden, Dresden, Germany
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5
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Tang CY, Mauro C. Similarities in the Metabolic Reprogramming of Immune System and Endothelium. Front Immunol 2017; 8:837. [PMID: 28785263 PMCID: PMC5519526 DOI: 10.3389/fimmu.2017.00837] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Accepted: 07/03/2017] [Indexed: 01/06/2023] Open
Abstract
Cellular metabolism has been known for its role in bioenergetics. In recent years, much light has been shed on the reprogrammable cellular metabolism underlying many vital cellular processes, such as cell activation, proliferation, and differentiation. Metabolic reprogramming in immune and endothelial cells (ECs) is being studied extensively. These cell compartments are implicated in inflammation and pathogenesis of many diseases but their similarities in metabolic reprogramming have not been analyzed in detail. One of the most notable metabolic reprogramming is the Warburg-like effect, famously described as one of the hallmarks of cancer cells. Immune cells and ECs can display this phenotype that is characterized by a metabolic switch favoring glycolysis over oxidative phosphorylation (OXPHOS) in aerobic conditions. Though energy-inefficient, aerobic glycolysis confers many benefits to the respiring cells ranging from higher rate of adenosine triphosphate production to maintaining redox homeostasis. Chemical and biological regulators either promote or perturb this effect. In this review, nitric oxide, hypoxia-inducible factor, and adenosine monophosphate-activated protein kinase have been discussed for their common involvement in metabolic reprogramming of both systems. From in vitro and animal studies, various discrepancies exist regarding the effects of those regulators on metabolic switch. However, it is generally accepted that glycolysis favors inflammatory reactions while OXPHOS favors anti-inflammatory processes. The reasons for such observation are currently subject of intense studies and not completely understood. Finally, metabolic reprogramming in immune cells and ECs does not limit to the physiological state in health but can also be observed in pathological states, such as atherosclerosis and cancer. These new insights provide us with a better understanding of the similarities in metabolic reprogramming across a number of cell types, which could pave the way for future research and possible metabolic-based therapeutics.
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Affiliation(s)
- Chu-Yik Tang
- Barts and The London School of Medicine and Dentistry, Institute of Health Sciences Education, Queen Mary University of London, London, United Kingdom
| | - Claudio Mauro
- Barts and The London School of Medicine and Dentistry, William Harvey Research Institute, Queen Mary University of London, London, United Kingdom
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6
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Chen SW, Lin YC, Chen RY, Hsieh TC, Yen KY, Liang JA, Yang SN, Wang YC, Chen YH, Chow NH, Kao CH. Immunohistochemical overexpression of hypoxia-induced factor 1α associated with slow reduction in 18fluoro-2-deoxy-D-glucose uptake for chemoradiotherapy in patients with pharyngeal cancer. Eur J Nucl Med Mol Imaging 2016; 43:2343-2352. [PMID: 27311919 DOI: 10.1007/s00259-016-3436-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Accepted: 06/02/2016] [Indexed: 10/21/2022]
Abstract
BACKGROUND This study examined genomic factors associated with a reduction in 18fluoro-2-deoxy-D-glucose (FDG) uptake during positron emission tomography-computed tomography (PET-CT) for definitive chemoradiotherapy (CRT) in patients with pharyngeal cancer. METHODS The pretreatment and interim PET-CT images of 25 patients with advanced pharyngeal cancers receiving definitive CRT were prospectively evaluated. The maximum standardized uptake value (SUVmax) of the interim PET-CT and the reduction ratio of the SUVmax (SRR) between the two images were measured. Genomic data from pretreatment incisional biopsy specimens (SLC2A1, CAIX, VEGF, HIF1A, BCL2, Claudin-4, YAP1, MET, MKI67, and EGFR) were analyzed using tissue microarrays. Differences in FDG uptake and SRRs between tumors with low and high gene expression were examined using the Mann-Whitney test. Cox regression analysis was performed to examine the effects of variables on local control. RESULTS The SRR of the primary tumors (SRR-P) was 0.59 ± 0.31, whereas the SRR of metastatic lymph nodes (SRR-N) was 0.54 ± 0.32. Overexpression of HIF1A was associated with a high iSUVmax of the primary tumor (P < 0.001) and neck lymph node (P = 0.04) and a low SRR-P (P = 0.02). Multivariate analysis revealed that patients who had tumors with low SRR-P or high HIF1A expression levels showed inferior local control. CONCLUSION In patients with pharyngeal cancer requiring CRT, HIF1A overexpression was positively associated with high interim SUVmax or a slow reduction in FDG uptake. Prospective trials are needed to determine whether the local control rate can be stratified using the HIF1A level as a biomarker and SRR-P.
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Affiliation(s)
- Shang-Wen Chen
- Department of Radiation Oncology, China Medical University Hospital, Taichung, Taiwan.,School of Medicine, China Medical University, Taichung, Taiwan.,School of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Ying-Chun Lin
- Department of Radiation Oncology, China Medical University Hospital, Taichung, Taiwan.,The Ph.D. Program for Cancer Biology and Drug Discovery, China Medical University and Academia Sinica, Taichung, Taiwan
| | - Rui-Yun Chen
- Department of Pathology, China Medical University Hospital, Taichung, Taiwan
| | - Te-Chun Hsieh
- Department of Nuclear Medicine and PET Center, China Medical University Hospital, Taichung, Taiwan.,Department of Biomedical Imaging and Radiological Science, China Medical University, Taichung, Taiwan
| | - Kuo-Yang Yen
- Department of Nuclear Medicine and PET Center, China Medical University Hospital, Taichung, Taiwan.,Department of Biomedical Imaging and Radiological Science, China Medical University, Taichung, Taiwan
| | - Ji-An Liang
- Department of Radiation Oncology, China Medical University Hospital, Taichung, Taiwan.,Graduate Institute of Clinical Medical Science, School of Medicine, College of Medicine, China Medical University, No. 2, Yuh-Der Road, Taichung, 40447, Taiwan
| | - Shih-Neng Yang
- Department of Radiation Oncology, China Medical University Hospital, Taichung, Taiwan.,Department of Biomedical Imaging and Radiological Science, China Medical University, Taichung, Taiwan
| | - Yao-Ching Wang
- Department of Radiation Oncology, China Medical University Hospital, Taichung, Taiwan
| | - Ya-Huey Chen
- Graduate Institute of Cancer Biology, China Medical University, Taichung, Taiwan.,Center for Molecular Medicine, China Medical University Hospital, Taichung, Taiwan
| | - Nan-Haw Chow
- Department of Pathology, National Cheng Kung University, Tainan, Taiwan
| | - Chia-Hung Kao
- Department of Nuclear Medicine and PET Center, China Medical University Hospital, Taichung, Taiwan. .,Graduate Institute of Clinical Medical Science, School of Medicine, College of Medicine, China Medical University, No. 2, Yuh-Der Road, Taichung, 40447, Taiwan.
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Experimental hypoxia does not influence gene expression and protein synthesis of Eph receptors and ephrin ligands in human melanoma cells in vitro. Melanoma Res 2014; 23:85-95. [PMID: 23358429 DOI: 10.1097/cmr.0b013e32835e58f3] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Eph receptor tyrosine kinases and their ephrin ligands are considered to play important roles in melanoma progression and metastasis. Moreover, hypoxia is known to contribute to melanoma metastasis. In this study, the influence of experimental hypoxia on the expression and synthesis of EphA2 and EphB4, and their corresponding ligands ephrinA1, ephrinA5, and ephrinB2 was studied systematically in four human melanoma cell lines in vitro. Melanoma cell monolayer and spheroid cultures were used as both extrinsic and intrinsic hypoxia models. Hypoxic conditions were confirmed by analyzing hypoxia-inducible factors 1α or 2α expression, vascular endothelial growth factor expression, and cellular uptake of [F]fluoromisonidazole. In normoxia, EphA2, EphB4, ephrinA1, ephrinA5, and ephrinB2 expression was detectable in all cell lines to varying extents. Considerable protein synthesis of EphA2 was detected in all cell lines. However, no effect of experimental hypoxia on both Eph/ephrin expression and protein synthesis was observed. This contributes critically to the debate on the hypothesis that hypoxia regulates the Eph/ephrin system in melanoma.
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Smith TAD, Zanda M, Fleming IN. Hypoxia stimulates 18F-fluorodeoxyglucose uptake in breast cancer cells via hypoxia inducible factor-1 and AMP-activated protein kinase. Nucl Med Biol 2013; 40:858-64. [PMID: 23786679 DOI: 10.1016/j.nucmedbio.2013.05.006] [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: 04/03/2013] [Revised: 05/10/2013] [Accepted: 05/12/2013] [Indexed: 12/23/2022]
Abstract
INTRODUCTION Hypoxia can stimulate (18)F-fluorodeoxyglucose (FDG) uptake in cultured cells. A better understanding of the underlying molecular mechanism is required to determine the value of FDG for studying tumour hypoxia. METHODS The effect of hypoxia on FDG uptake, and key proteins involved in glucose transport and glycolysis, was studied in MCF7 and MDA231 breast cancer cell lines. RESULTS Hypoxia induced a dose- and time-dependent increase in FDG uptake. The FDG increase was transient, suggesting that FDG uptake is only likely to be increased by acute hypoxia (<24 h). Molecular analysis indicated that hypoxia upregulated glut1 and 6-phosphofructo-2-kinase, key proteins involved in regulating glucose transport and glycolysis, and that these changes were induced by Hypoxia-Inducible factor 1 (HIF1) upregulation and/or AMP-activated protein kinase activation. CONCLUSIONS FDG may provide useful information about the oxygenation status of cells in hypoxic regions where HIF1 upregulation is hypoxia-driven.
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Affiliation(s)
- Tim A D Smith
- Division of Applied Medicine, School of Medicine and Dentistry, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD
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9
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Investigating the antiproliferative activity of high affinity DNA aptamer on cancer cells. PLoS One 2013; 8:e50964. [PMID: 23341879 PMCID: PMC3547035 DOI: 10.1371/journal.pone.0050964] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2012] [Accepted: 10/29/2012] [Indexed: 12/02/2022] Open
Abstract
Vascular endothelial growth factor (VEGF) is an angiogenic mitogen involved in promoting tumor angiogenesis inside the body. VEGF is a key protein required for progression of tumor from benign to malignant phenotype. In this study, we investigated the binding affinity of a previously selected 26-mer DNA aptamer sequence (SL2-B) against heparin binding domain (HBD) of VEGF165 protein. The SL2-B was first chemically modified by introduction of phosphorothioate linkages (PS-linkages). Subsequently, surface plasmon resonance (SPR) spectroscopy and circular dichroism (CD) were used to determine the binding affinity, specificity and to deduce the conformation of PS-modified SL2-B sequence. Finally, antiproliferative activity of the modified SL2-B sequence on Hep G2 cancer cells was investigated. Our results demonstrate a marked enhancement in the biostability of the SL2-B sequence after PS modification. The modified SL2-B sequence also exhibits enhanced antiproliferative activity against Hep G2 cancer cells in hypoxia conditions. In addition, modified SL2-B sequence inhibits the expression of Jagged-1 protein, which is one of the ligands to VEGF linked delta/jagged-notch signaling pathway.
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10
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Chouinard JA, Rousseau JA, Beaudoin JF, Vermette P, Lecomte R. Positron emission tomography detection of human endothelial cell and fibroblast monolayers: effect of pretreament and cell density on 18FDG uptake. Vasc Cell 2012; 4:5. [PMID: 22433292 PMCID: PMC3349599 DOI: 10.1186/2045-824x-4-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2012] [Accepted: 03/20/2012] [Indexed: 11/16/2022] Open
Abstract
Background The non-destructive assessment and characterization of tridimensional (3D) cell and tissue constructs in bioreactors represents a challenge in tissue engineering. Medical imaging modalities, which can provide information on the structure and function of internal organs and tissues in living organisms, have the potential of allowing repetitive monitoring of these 3D cultures in vitro. Positron emission tomography (PET) is the most sensitive non-invasive imaging modality, capable of measuring picomolar amounts of radiolabeled molecules. However, since PET imaging protocols have been designed almost exclusively for in vivo investigations, suitable methods must be devised to enable imaging of cells or tissue substitutes. As a prior step to imaging 3D cultures, cell radiotracer uptake conditions must first be optimized. Methods In this study, human umbilical vein endothelial cells (HUVEC) and human fibroblasts were cultured at different densities and PET was used to non-destructively monitor their glycolytic activity by measuring 18F-fluorodeoxyglucose (18FDG) uptake. Various cell preconditioning protocols were investigated by adjusting the following parameters to optimize 18FDG uptake: glucose starvation, insulin stimulation, glucose concentration, 18FDG incubation time, cell density and radiotracer efflux prevention. Results The conditions yielding optimal 18FDG uptake, and hence best detection sensitivity by PET, were as follows: 2-hour cell preconditioning by glucose deprivation with 1-hour insulin stimulation, followed by 1-hour 18FDG incubation and 15-minute stabilization in standard culture medium, prior to rinsing and PET scanning. Conclusions A step-wise dependence of 18FDG uptake on glucose concentration was found, but a linear correlation between PET signal and cell density was observed. Detection thresholds of 36 ± 7 and 21 ± 4 cells were estimated for endothelial cells and fibroblasts, respectively.
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Affiliation(s)
- Julie A Chouinard
- Sherbrooke Molecular Imaging Centre, Department of Nuclear Medicine and Radiobiology, Université de Sherbrooke, 3001, 12ième Avenue Nord, Sherbrooke, Québec J1H 5N4, Canada.
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11
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Kaur H, Yung LYL. Probing high affinity sequences of DNA aptamer against VEGF165. PLoS One 2012; 7:e31196. [PMID: 22359573 PMCID: PMC3281051 DOI: 10.1371/journal.pone.0031196] [Citation(s) in RCA: 106] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2011] [Accepted: 01/03/2012] [Indexed: 11/19/2022] Open
Abstract
Vascular endothelial growth factor (VEGF165) is a potent angiogenic mitogen commonly overexpressed in cancerous cells. It contains two main binding domains, the receptor-binding domain (RBD) and the heparin-binding domain (HBD). This study attempted to identify the specific sequences of the VEa5 DNA aptamer that exhibit high binding affinity towards the VEGF165 protein by truncating the original VEa5 aptamer into different segments. Using surface plasmon resonance (SPR) spectroscopy for binding affinity analysis, one of the truncated aptamers showed a >200-fold increase in the binding affinity for HBD. This truncated aptamer also exhibited high specificity to HBD with negligible binding affinity for VEGF121, an isoform of VEGF lacking HBD. Exposing colorectal cancer cells to the truncated aptamer sequence further confirmed the binding affinity and specificity of the aptamer to the target VEGF165 protein. Hence, our approach of aptamer truncation can potentially be useful in identifying high affinity aptamer sequences for the biological molecules and targeting them as antagonist for cancer cell detection.
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Affiliation(s)
- Harleen Kaur
- Department of Chemical and Biomolecular Engineering, National University of Singapore, Singapore, Singapore
| | - Lin-Yue Lanry Yung
- Department of Chemical and Biomolecular Engineering, National University of Singapore, Singapore, Singapore
- * E-mail:
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Paik JY, Park JW, Jung KH, Lee EJ, Lee KH. Combination of nitric oxide stimulation with high-dose 18F-FDG promotes apoptosis and enhances radiation therapy of endothelial cells. Nucl Med Biol 2011; 39:423-8. [PMID: 22079039 DOI: 10.1016/j.nucmedbio.2011.09.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2011] [Revised: 08/31/2011] [Accepted: 09/15/2011] [Indexed: 12/20/2022]
Abstract
INTRODUCTION High-dose (18)F-FDG can provide targeted nuclear therapy of cancer. Endothelial cell injury is a key determinant of tumor response to radiotherapy. Here, we tested the hypothesis that activation of endothelial cell glycolytic metabolism with nitric oxide can enhance the therapeutic effect of high-dose (18)F-FDG. METHODS Calf pulmonary artery endothelial (CPAE) cells were treated with graded doses of (18)F-FDG. Glycolysis was stimulated by 24 h of exposure to the nitric oxide donor, sodium nitroprusside (SNP). Cell viability was assessed by MTT and clonogenic assays. Apoptosis was evaluated by ELISA of cytosolic DNA fragments and Western blots of cleaved caspase-3. RESULTS SNP stimulation (0.1 and 1 mM) augmented CPAE cell (18)F-FDG uptake to 2.6- and 4.6-fold of controls without adverse effects. Treatment with 333 μCi/ml (18)F-FDG alone reduced viable cell number to 35.4% of controls by Day 3. Combining 0.1 mM SNP stimulation significantly enhanced the killing effect, reducing cell numbers to 19.2% and 39.2% of controls by 333 and 167 μCi/ml of (18)F-FDG, respectively. (18)F-FDG also suppressed clonogenic survival to 80.8% and 43.2% of controls by 83 and 167 μCi/ml, which was again intensified by SNP to 59.7% and 21.1% of controls. The cytotoxic effect of (18)F-FDG was attributed to induction of apoptosis as shown by increased cytosolic fragmented DNA and cleaved caspase-3 levels (26.4% and 30.7% increases by 167 μCi/ml). Combining SNP stimulation significantly increased both of these levels to 1.8-fold of control cells. CONCLUSION High-dose (18)F-FDG combined with nitric oxide-stimulated glycolysis is an effective method to inhibit endothelial cell survival and promote apoptosis. These results suggest a potential role of this strategy for targeted radiotherapy of angiogenic vasculature.
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Affiliation(s)
- Jin-Young Paik
- Department of Nuclear Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
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Wuest M, Trayner BJ, Grant TN, Jans HS, Mercer JR, Murray D, West FG, McEwan AJB, Wuest F, Cheeseman CI. Radiopharmacological evaluation of 6-deoxy-6-[18F]fluoro-D-fructose as a radiotracer for PET imaging of GLUT5 in breast cancer. Nucl Med Biol 2011; 38:461-75. [PMID: 21531283 DOI: 10.1016/j.nucmedbio.2010.11.004] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2010] [Revised: 10/29/2010] [Accepted: 11/16/2010] [Indexed: 12/25/2022]
Abstract
INTRODUCTION Several clinical studies have shown low or no expression of GLUT1 in breast cancer patients, which may account for the low clinical specificity and sensitivity of 2-deoxy-2-[(18)F]fluoro-D-glucose ([(18)F]FDG) used in positron emission tomography (PET). Therefore, it has been proposed that other tumor characteristics such as the high expression of GLUT2 and GLUT5 in many breast tumors could be used to develop alternative strategies to detect breast cancer. Here we have studied the in vitro and in vivo radiopharmacological profile of 6-deoxy-6-[(18)F]fluoro-D-fructose (6-[(18)F]FDF) as a potential PET radiotracer to image GLUT5 expression in breast cancers. METHODS Uptake of 6-[(18)F]FDF was studied in murine EMT-6 and human MCF-7 breast cancer cells over 60 min and compared to [(18)F]FDG. Biodistribution of 6-[(18)F]FDF was determined in BALB/c mice. Tumor uptake was studied with dynamic small animal PET in EMT-6 tumor-bearing BALB/c mice and human xenograft MCF-7 tumor-bearing NIH-III mice in comparison to [(18)F]FDG. 6-[(18)F]FDF metabolism was investigated in mouse blood and urine. RESULTS 6-[(18)F]FDF is taken up by EMT-6 and MCF-7 breast tumor cells independent of extracellular glucose levels but dependent on the extracellular concentration of fructose. After 60 min, 30±4% (n=9) and 12±1% (n=7) ID/mg protein 6-[(18)F]FDF was found in EMT-6 and MCF-7 cells, respectively. 6-deoxy-6-fluoro-d-fructose had a 10-fold higher potency than fructose to inhibit 6-[(18)F]FDF uptake into EMT-6 cells. Biodistribution in normal mice revealed radioactivity uptake in bone and brain. Radioactivity was accumulated in EMT-6 tumors reaching 3.65±0.30% ID/g (n=3) at 5 min post injection and decreasing to 1.75±0.03% ID/g (n=3) at 120 min post injection. Dynamic small animal PET showed significantly lower radioactivity uptake after 15 min post injection in MCF-7 tumors [standard uptake value (SUV)=0.76±0.05; n=3] compared to EMT-6 tumors (SUV=1.23±0.09; n=3). Interestingly, [(18)F]FDG uptake was significantly different in MCF-7 tumors (SUV(15 min) 0.74±0.12 to SUV(120 min) 0.80±0.15; n=3) versus EMT-6 tumors (SUV(15 min) 1.01±0.33 to SUV(120 min) 1.80±0.25; n=3). 6-[(18)F]FDF was shown to be a substrate for recombinant human ketohexokinase, and it was metabolized rapidly in vivo. CONCLUSION Based on the GLUT5 specific transport and phosphorylation by ketohexokinase, 6-[(18)F]FDF may represent a novel radiotracer for PET imaging of GLUT5 and ketohexokinase-expressing tumors.
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Affiliation(s)
- Melinda Wuest
- Department of Oncology, University of Alberta-Cross Cancer Institute, Edmonton, AB-T6G 1Z2, Canada.
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Hoigebazar L, Jeong JM, Choi SY, Choi JY, Shetty D, Lee YS, Lee DS, Chung JK, Lee MC, Chung YK. Synthesis and Characterization of Nitroimidazole Derivatives for 68Ga-Labeling and Testing in Tumor Xenografted Mice. J Med Chem 2010; 53:6378-85. [DOI: 10.1021/jm100545a] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- Lathika Hoigebazar
- Department of Nuclear Medicine, Radiation Applied Life Sciences, Institute of Radiation Medicine, Seoul National University College of Medicine, 101 Daehangno, Jongno-gu, Seoul 110-744, Korea
- Cancer Research Institute, Seoul National University College of Medicine, Seoul 110-744, Korea
| | - Jae Min Jeong
- Department of Nuclear Medicine, Radiation Applied Life Sciences, Institute of Radiation Medicine, Seoul National University College of Medicine, 101 Daehangno, Jongno-gu, Seoul 110-744, Korea
- Cancer Research Institute, Seoul National University College of Medicine, Seoul 110-744, Korea
| | - Soo Young Choi
- Intelligent Textile System Research Centre and Department of Chemistry, Seoul National University, Seoul, Korea
| | - Jae Yeon Choi
- Department of Nuclear Medicine, Radiation Applied Life Sciences, Institute of Radiation Medicine, Seoul National University College of Medicine, 101 Daehangno, Jongno-gu, Seoul 110-744, Korea
- Cancer Research Institute, Seoul National University College of Medicine, Seoul 110-744, Korea
| | - Dinesh Shetty
- Department of Nuclear Medicine, Radiation Applied Life Sciences, Institute of Radiation Medicine, Seoul National University College of Medicine, 101 Daehangno, Jongno-gu, Seoul 110-744, Korea
- Cancer Research Institute, Seoul National University College of Medicine, Seoul 110-744, Korea
| | - Yun-Sang Lee
- Department of Nuclear Medicine, Radiation Applied Life Sciences, Institute of Radiation Medicine, Seoul National University College of Medicine, 101 Daehangno, Jongno-gu, Seoul 110-744, Korea
- Cancer Research Institute, Seoul National University College of Medicine, Seoul 110-744, Korea
| | - Dong Soo Lee
- Department of Nuclear Medicine, Radiation Applied Life Sciences, Institute of Radiation Medicine, Seoul National University College of Medicine, 101 Daehangno, Jongno-gu, Seoul 110-744, Korea
- Cancer Research Institute, Seoul National University College of Medicine, Seoul 110-744, Korea
| | - June-Key Chung
- Department of Nuclear Medicine, Radiation Applied Life Sciences, Institute of Radiation Medicine, Seoul National University College of Medicine, 101 Daehangno, Jongno-gu, Seoul 110-744, Korea
- Cancer Research Institute, Seoul National University College of Medicine, Seoul 110-744, Korea
| | - Myung Chul Lee
- Department of Nuclear Medicine, Radiation Applied Life Sciences, Institute of Radiation Medicine, Seoul National University College of Medicine, 101 Daehangno, Jongno-gu, Seoul 110-744, Korea
- Cancer Research Institute, Seoul National University College of Medicine, Seoul 110-744, Korea
| | - Young Keun Chung
- Intelligent Textile System Research Centre and Department of Chemistry, Seoul National University, Seoul, Korea
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Mosch B, Mueller K, Steinbach J, Pietzsch J. Influence of irradiation on metabolism and metastatic potential of B16-F10 melanoma cells. Int J Radiat Biol 2009; 85:1002-12. [PMID: 19895277 DOI: 10.3109/09553000903258871] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
PURPOSE To analyse short term and long term X-ray irradiation effects on proliferation, viability, glucose and amino acid uptake of murine melanoma cells in vitro and metastasis in vivo. MATERIALS AND METHODS B16-F10 melanoma cells were irradiated with different doses of X-ray irradiation (200 kV) in the range from 1-20 Gy. One, two and three days respectively 7, 14 and 21 days after treatment cells were analysed concerning cell growth, viability, proliferation, cell cycle distribution, glucose and amino acid transport. Moreover the capability of the cells for in vivo metastasis was examined. RESULTS As short term response on irradiation we detected decreased cell growth, viability and arrest in the G2/M phase of the cell cycle. Long term response involves re-start of proliferation, increased cell growth and glucose uptake but still decreased viability and amino acid transport. In vivo metastasis is lost immediately after irradiation and regained to a low extent beyond two weeks time for recurrence of cells before injection. CONCLUSIONS In vitro data suggest that surviving melanoma cells compensate the initial irradiation-dependent damage of proliferation within three weeks possibly by increase in glucose uptake. For metastasis in vivo the role of additional mechanisms is strongly suggested.
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Affiliation(s)
- Birgit Mosch
- Department of Radiopharmaceutical Biology, Forschungszentrum Dresden-Rossendorf, Institute of Radiopharmacy, Dresden, Germany.
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Molecular imaging of hypoxia with radiolabelled agents. Eur J Nucl Med Mol Imaging 2009; 36:1674-86. [PMID: 19565239 PMCID: PMC2758191 DOI: 10.1007/s00259-009-1195-9] [Citation(s) in RCA: 124] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2009] [Accepted: 06/07/2009] [Indexed: 01/29/2023]
Abstract
Tissue hypoxia results from an inadequate supply of oxygen (O2) that compromises biological functions. Structural and functional abnormalities of the tumour vasculature together with altered diffusion conditions inside the tumour seem to be the main causes of tumour hypoxia. Evidence from experimental and clinical studies points to a role for tumour hypoxia in tumour propagation, resistance to therapy and malignant progression. This has led to the development of assays for the detection of hypoxia in patients in order to predict outcome and identify patients with a worse prognosis and/or patients that would benefit from appropriate treatments. A variety of invasive and non-invasive approaches have been developed to measure tumour oxygenation including oxygen-sensitive electrodes and hypoxia marker techniques using various labels that can be detected by different methods such as positron emission tomography (PET), single photon emission computed tomography (SPECT), magnetic resonance imaging (MRI), autoradiography and immunohistochemistry. This review aims to give a detailed overview of non-invasive molecular imaging modalities with radiolabelled PET and SPECT tracers that are available to measure tumour hypoxia.
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Paik JY, Ko BH, Jung KH, Lee KH. Fibronectin Stimulates Endothelial Cell 18F-FDG Uptake Through Focal Adhesion Kinase–Mediated Phosphatidylinositol 3-Kinase/Akt Signaling. J Nucl Med 2009; 50:618-24. [DOI: 10.2967/jnumed.108.059386] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
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FDG uptake, a surrogate of tumour hypoxia? Eur J Nucl Med Mol Imaging 2008; 35:1544-9. [PMID: 18509637 PMCID: PMC2491423 DOI: 10.1007/s00259-008-0758-5] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2007] [Accepted: 02/18/2008] [Indexed: 02/08/2023]
Abstract
INTRODUCTION Tumour hyperglycolysis is driven by activation of hypoxia-inducible factor-1 (HIF-1) through tumour hypoxia. Accordingly, the degree of 2-fluro-2-deoxy-D: -glucose (FDG) uptake by tumours might indirectly reflect the level of hypoxia, obviating the need for more specific radiopharmaceuticals for hypoxia imaging. DISCUSSION In this paper, available data on the relationship between hypoxia and FDG uptake by tumour tissue in vitro and in vivo are reviewed. In pre-clinical in vitro studies, acute hypoxia was consistently shown to increase FDG uptake by normal and tumour cells within a couple of hours after onset with mobilisation or modification of glucose transporters optimising glucose uptake, followed by a delayed response with increased rates of transcription of GLUT mRNA. In pre-clinical imaging studies on chronic hypoxia that compared FDG uptake by tumours grown in rat or mice to uptake by FMISO, the pattern of normoxic and hypoxic regions within the human tumour xenografts, as imaged by FMISO, largely correlated with glucose metabolism although minor locoregional differences could not be excluded. In the clinical setting, data are limited and discordant. CONCLUSION Further evaluation of FDG uptake by various tumour types in relation to intrinsic and bioreductive markers of hypoxia and response to radiotherapy or hypoxia-dependent drugs is needed to fully assess its application as a marker of hypoxia in the clinical setting.
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