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Ong HC, Coimbra JTS, Ramos MJ, Xing B, Fernandes PA, García F. Beyond the TPP + "gold standard": a new generation mitochondrial delivery vector based on extended PN frameworks. Chem Sci 2023; 14:4126-4133. [PMID: 37063789 PMCID: PMC10094279 DOI: 10.1039/d2sc06508h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Accepted: 02/13/2023] [Indexed: 02/17/2023] Open
Abstract
Mitochondrial targeting represents an attractive strategy for treating metabolic, degenerative and hyperproliferative diseases, since this organelle plays key roles in essential cellular functions. Triphenylphosphonium (TPP+) moieties - the current "gold standard" - have been widely used as mitochondrial targeting vectors for a wide range of molecular cargo. Recently, further optimisation of the TPP+ platform drew considerable interest as a way to enhance mitochondrial therapies. However, although the modification of this system appears promising, the core structure of the TPP+ moiety remains largely unchanged. Thus, this study explored the use of aminophosphonium (PN+) and phosphazenylphosphonium (PPN+) main group frameworks as novel mitochondrial delivery vectors. The PPN+ moiety was found to be a highly promising platform for this purpose, owing to its unique electronic properties and high lipophilicity. This has been demonstrated by the high mitochondrial accumulation of a PPN+-conjugated fluorophore relative to its TPP+-conjugated counterpart, and has been further supported by density functional theory and molecular dynamics calculations, highlighting the PPN+ moiety's unusual electronic properties. These results demonstrate the potential of novel phosphorus-nitrogen based frameworks as highly effective mitochondrial delivery vectors over traditional TPP+ vectors.
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Affiliation(s)
- How Chee Ong
- School of Physical and Mathematical Sciences, Division of Chemistry and Biological Chemistry, Nanyang Technological University 21 Nanyang Link 637371 Singapore
| | - João T S Coimbra
- LAQV/REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto Rua do Campo Alegre 687, s/n 4169-007 Porto Portugal
| | - Maria J Ramos
- LAQV/REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto Rua do Campo Alegre 687, s/n 4169-007 Porto Portugal
| | - Bengang Xing
- School of Physical and Mathematical Sciences, Division of Chemistry and Biological Chemistry, Nanyang Technological University 21 Nanyang Link 637371 Singapore
| | - Pedro A Fernandes
- LAQV/REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto Rua do Campo Alegre 687, s/n 4169-007 Porto Portugal
| | - Felipe García
- Departamento de Química Orgánica e Inorgánica, Facultad de Química, Universidad de Oviedo Avda Julian Claveria 8 33006 Asturias Spain
- School of Chemistry, Monash University Clayton Victoria 3800 Australia
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2
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Ong HC, Coimbra JTS, Kwek G, Ramos MJ, Xing B, Fernandes PA, García F. Alkyl vs. aryl modifications: a comparative study on modular modifications of triphenylphosphonium mitochondrial vectors. RSC Chem Biol 2021; 2:1643-1650. [PMID: 34977579 PMCID: PMC8637833 DOI: 10.1039/d1cb00099c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2021] [Accepted: 08/21/2021] [Indexed: 11/21/2022] Open
Abstract
Triphenylphosphonium (TPP+) moieties are commonly conjugated to drug molecules to confer mitochondrial selectivity due to their positive charge and high lipophilicity. Although optimisation of lipophilicity can be achieved by modifying the length of the alkyl linkers between the TPP+ moiety and the drug molecule, it is not always possible. While methylation of the TPP+ moiety is a viable alternative to increase lipophilicity and mitochondrial accumulation, there are no studies comparing these two separate modular approaches. Thus, we have systematically designed, synthesised and tested a range of TPP+ molecules with varying alkyl chain lengths and degree of aryl methylation to compare the two modular methodologies for modulating lipophilicity. The ability of aryl/alkyl modified TPP+ to deliver cargo to the mitochondria was also evaluated by confocal imaging with a TPP+-conjugated fluorescein-based fluorophore. Furthermore, we have employed molecular dynamics simulations to understand the translocation of these molecules through biological membrane model systems. These results provide further insights into the thermodynamics of this process and the effect of alkyl and aryl modular modifications. Alkyl chain extension and aryl methylation can be employed to enhance mitochondrial uptake in triphenylphosphonium vectors. Here we compare these complementary strategies and their mitochondrial-targeting effects using a modular synthetic approach.![]()
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Affiliation(s)
- How Chee Ong
- School of Physical and Mathematical Sciences, Division of Chemistry and Biological Chemistry, Nanyang Technological University 21 Nanyang Link 637371 Singapore
| | - João T S Coimbra
- LAQV, REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto Rua do Campo Alegre s/n 4169-007 Portugal
| | - Germain Kwek
- School of Physical and Mathematical Sciences, Division of Chemistry and Biological Chemistry, Nanyang Technological University 21 Nanyang Link 637371 Singapore
| | - Maria J Ramos
- LAQV, REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto Rua do Campo Alegre s/n 4169-007 Portugal
| | - Bengang Xing
- School of Physical and Mathematical Sciences, Division of Chemistry and Biological Chemistry, Nanyang Technological University 21 Nanyang Link 637371 Singapore
| | - Pedro A Fernandes
- LAQV, REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto Rua do Campo Alegre s/n 4169-007 Portugal
| | - Felipe García
- School of Physical and Mathematical Sciences, Division of Chemistry and Biological Chemistry, Nanyang Technological University 21 Nanyang Link 637371 Singapore
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3
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Osborne BE, Yue TTC, Waters ECT, Baark F, Southworth R, Long NJ. Synthesis and ex vivo biological evaluation of gallium-68 labelled NODAGA chelates assessing cardiac uptake and retention. Dalton Trans 2021; 50:14695-14705. [PMID: 34585706 DOI: 10.1039/d1dt02224e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Radiolabelled lipophilic cations can be used to non-invasively report on mitochondrial dysfunction in diseases such as cardiovascular disease, cardiotoxicity and cancer. Several such lipophilic cations are currently used clinically to map myocardial perfusion using SPECT imaging. Since PET offers significant advantages over SPECT in terms of sensitivity, resolution and the capacity for dynamic imaging to allow pharmacokinetic modelling, we have synthesised and radiolabelled a series of NODAGA-based radiotracers, with triarylphosphonium-functionalisation, with gallium-68 to develop PET-compatible cationic complexes. To evaluate their capacity to report upon mitochondrial membrane potential, we assessed their pharmacokinetic profiles in isolated perfused rat hearts before and after mitochondrial depolarisation with the ionophore CCCP. All three tracers radiolabel with over 96% RCY, with log D7.4 values above -0.4 observed for the most lipophilic example of this family of radiotracers. The candidate tracer [68Ga]Ga4c exhibited non-preferential uptake in healthy cardiac tissue over CCCP-infused cardiac tissue. While this approach does show promise, the lipophilicity of this family of probes needs improving in order for them to be effective cardiac imaging agents.
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Affiliation(s)
- Bradley E Osborne
- Department of Chemistry, Imperial College London, Molecular Sciences Research Hub, White City Campus, Wood Lane, London, W12 0BZ, UK. .,School of Biomedical Engineering and Imaging Sciences, King's College London, 4th Floor Lambeth Wing, St Thomas' Hospital, London, SE1 7EH, UK.
| | - Thomas T C Yue
- Department of Chemistry, Imperial College London, Molecular Sciences Research Hub, White City Campus, Wood Lane, London, W12 0BZ, UK.
| | - Edward C T Waters
- School of Biomedical Engineering and Imaging Sciences, King's College London, 4th Floor Lambeth Wing, St Thomas' Hospital, London, SE1 7EH, UK.
| | - Friedrich Baark
- School of Biomedical Engineering and Imaging Sciences, King's College London, 4th Floor Lambeth Wing, St Thomas' Hospital, London, SE1 7EH, UK.
| | - Richard Southworth
- School of Biomedical Engineering and Imaging Sciences, King's College London, 4th Floor Lambeth Wing, St Thomas' Hospital, London, SE1 7EH, UK.
| | - Nicholas J Long
- Department of Chemistry, Imperial College London, Molecular Sciences Research Hub, White City Campus, Wood Lane, London, W12 0BZ, UK.
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4
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Smith AJ, Osborne BE, Keeling GP, Blower PJ, Southworth R, Long NJ. DO2A-based ligands for gallium-68 chelation: synthesis, radiochemistry and ex vivo cardiac uptake. Dalton Trans 2020; 49:1097-1106. [DOI: 10.1039/c9dt02354b] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
New DO2A-based lipophilic and cationic chelators for gallium-68 have been synthesised for cardiac PET imaging. These radiotracers show preferential uptake in healthy cardiac tissue over cardiac tissue depolarised by CCCP.
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Affiliation(s)
- Adam J. Smith
- Department of Chemistry
- Imperial College London
- Molecular Sciences Research Hub
- London
- UK
| | - Bradley E. Osborne
- Department of Chemistry
- Imperial College London
- Molecular Sciences Research Hub
- London
- UK
| | - George P. Keeling
- School of Biomedical Engineering and Imaging Sciences
- King's College London
- London
- UK
| | - Philip J. Blower
- School of Biomedical Engineering and Imaging Sciences
- King's College London
- London
- UK
| | - Richard Southworth
- School of Biomedical Engineering and Imaging Sciences
- King's College London
- London
- UK
| | - Nicholas J. Long
- Department of Chemistry
- Imperial College London
- Molecular Sciences Research Hub
- London
- UK
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5
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Ong HC, Hu Z, Coimbra JTS, Ramos MJ, Kon OL, Xing B, Yeow EKL, Fernandes PA, García F. Enabling Mitochondrial Uptake of Lipophilic Dications Using Methylated Triphenylphosphonium Moieties. Inorg Chem 2019; 58:8293-8299. [DOI: 10.1021/acs.inorgchem.8b03380] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- How Chee Ong
- School of Physical and Mathematical Sciences, Division of Chemistry and Biological Chemistry, Nanyang Technological University, 21 Nanyang Link, 637371, Singapore
| | - Zhang Hu
- School of Physical and Mathematical Sciences, Division of Chemistry and Biological Chemistry, Nanyang Technological University, 21 Nanyang Link, 637371, Singapore
| | - João T. S. Coimbra
- UCIBIO, REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre s/n, 4169-007, Porto, Portugal
| | - Maria J. Ramos
- UCIBIO, REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre s/n, 4169-007, Porto, Portugal
| | - Oi Lian Kon
- Division of Medical Sciences, Laboratory of Applied Human Genetics, Humphrey Oei Institute of Cancer Research, National Cancer Centre, 169610, Singapore
| | - Bengang Xing
- School of Physical and Mathematical Sciences, Division of Chemistry and Biological Chemistry, Nanyang Technological University, 21 Nanyang Link, 637371, Singapore
| | - Edwin K. L. Yeow
- School of Physical and Mathematical Sciences, Division of Chemistry and Biological Chemistry, Nanyang Technological University, 21 Nanyang Link, 637371, Singapore
| | - Pedro A. Fernandes
- UCIBIO, REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre s/n, 4169-007, Porto, Portugal
| | - Felipe García
- School of Physical and Mathematical Sciences, Division of Chemistry and Biological Chemistry, Nanyang Technological University, 21 Nanyang Link, 637371, Singapore
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6
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McCluskey SP, Haslop A, Coello C, Gunn RN, Tate EW, Southworth R, Plisson C, Long NJ, Wells LA. Imaging of Chemotherapy-Induced Acute Cardiotoxicity with 18F-Labeled Lipophilic Cations. J Nucl Med 2019; 60:1750-1756. [PMID: 31147403 DOI: 10.2967/jnumed.119.226787] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Accepted: 05/29/2019] [Indexed: 12/25/2022] Open
Abstract
Many chemotherapy agents are toxic to the heart, such that increasing numbers of cancer survivors are now living with the potentially lethal cardiovascular consequences of their treatment. Earlier and more sensitive detection of chemotherapy-induced cardiotoxicity may allow improved treatment strategies and increase long-term survival. Lipophilic cation PET tracers may be suitable for early detection of cardiotoxicity. This study aimed to evaluate an 18F-labeled lipophilic phosphonium cation, [1-(2-18F-fluoroethyl),1H[1,2,3]triazole-4-ethylene]triphenylphosphonium bromide (18F-MitoPhos), as a cardiac imaging agent, comparing it with leading PET and SPECT lipophilic cationic tracers before further assessing its potential for imaging cardiotoxicity in an acute doxorubicin model. Methods: Cardiac uptake and response to decreased mitochondrial membrane potential of 18F-MitoPhos and 99mTc-sestamibi were tested in isolated perfused rat hearts. Baseline pharmacokinetic profiles of 18F-MitoPhos and 18F-fluorobenzyltriphenylphosphonium and their response to acute doxorubicin-induced cardiotoxicity were assessed in rats in vivo (10, 15, or 20 mg of doxorubicin per kilogram, intravenously, 48 h beforehand). Results: Cardiac retention of 18F-MitoPhos was more than double that of 99mTc-sestamibi in isolated perfused rat hearts. A favorable biodistribution of 18F-MitoPhos in vivo was observed, with heart-to-tissue ratios of 304 ± 186, 11.2 ± 1.2, and 3.8 ± 0.6 for plasma, liver, and lung, respectively (60 min). A significant dose-dependent loss of cardiac retention of 18F-MitoPhos was observed on doxorubicin treatment, with average cardiac SUV from 30 to 60 min (mean ± SD) decreasing from 3.5 ± 0.5 (control) to 1.8 ± 0.1 (doxorubicin, 20 mg/kg). Other assessed biomarkers showed no alterations. Conclusion: 18F-MitoPhos showed pharmacokinetic parameters suitable for cardiac imaging. A significant dose response of cardiac uptake to doxorubicin treatment was observed before detectable biomarker alterations. 18F-MitoPhos is therefore a promising tracer for imaging chemotherapy-induced cardiotoxicity. To our knowledge, this is the first demonstration of radiolabeled lipophilic cations being used for the PET imaging of chemotherapy-induced cardiotoxicity and indicates the potential application of these compounds in this area.
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Affiliation(s)
- Stuart P McCluskey
- Department of Chemistry, Imperial College London, London, United Kingdom.,Invicro LLC, London, United Kingdom
| | - Anna Haslop
- Department of Chemistry, Imperial College London, London, United Kingdom
| | | | - Roger N Gunn
- Invicro LLC, London, United Kingdom.,Division of Brain Sciences, Imperial College London, Imperial College Centre for Drug Discovery Science, London, United Kingdom; and
| | - Edward W Tate
- Department of Chemistry, Imperial College London, London, United Kingdom
| | - Richard Southworth
- Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
| | | | - Nicholas J Long
- Department of Chemistry, Imperial College London, London, United Kingdom
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7
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Smith AJ, Gawne PJ, Ma MT, Blower PJ, Southworth R, Long NJ. Synthesis, gallium-68 radiolabelling and biological evaluation of a series of triarylphosphonium-functionalized DO3A chelators. Dalton Trans 2018; 47:15448-15457. [PMID: 30328444 DOI: 10.1039/c8dt02966k] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Radiolabelled lipophilic cations that accumulate in mitochondria according to the magnitude of the mitochondrial membrane potential can be used to report non-invasively on mitochondrial dysfunction in cardiovascular disease, cardiotoxicity, and cancer. While several such cations are already commercially available for SPECT imaging, PET offers greater promise in terms of sensitivity, resolution, and capacity for dynamic imaging and pharmacokinetic modelling. We have therefore synthesised a series of three triarylphosphonium-functionalised DO3A chelators for positron emitter gallium-68, with differing alkyl-functionalisation motifs to provide opportunities for tunable lipophilicity as a means of optimising their pharmacokinetics. To assess their capacity to report on mitochondrial membrane potential, we assessed their pharmacokinetic profiles in isolated tumour cells and isolated perfused rat hearts before and after mitochondrial depolarisation with the ionophore CCCP. All three compounds radiolabelled with over 97% RCY and exhibited log D values of between -3.12 and -1.81. In vitro assessment of the uptake of the radiotracers in cultured tumour cells showed a three-fold increase in uptake compared to unchelated [68Ga]Ga(iii). However, each complex exhibited less than 1% retention in healthy hearts, which was not significantly diminished by mitochondrial depolarisation with CCCP. This preliminary work suggests that while this approach is promising, the lipophilicity of this class of tracers must be increased in order for them to be useful as cardiac or cancer imaging agents.
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Affiliation(s)
- Adam J Smith
- Department of Chemistry, Imperial College London, Molecular Sciences Research Hub, White City Campus, 80 Wood Lane, W12 0BZ, UK.
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8
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Kim DY, Cho SG, Bom HS. Emerging Tracers for Nuclear Cardiac PET Imaging. Nucl Med Mol Imaging 2018; 52:266-278. [PMID: 30100939 PMCID: PMC6066491 DOI: 10.1007/s13139-018-0521-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Revised: 03/05/2018] [Accepted: 04/12/2018] [Indexed: 12/16/2022] Open
Abstract
Myocardial perfusion imaging using positron emission tomography (PET) has several advantages over single photon emission computed tomography (SPECT). The recent advances in SPECT technology have shown promise, but there is still a large need for PET in the clinical management of coronary artery disease (CAD). Especially, absolute quantification of myocardial blood flow (MBF) using PET is extremely important. In spite of considerable advances in the diagnosis of CAD, novel PET radiopharmaceuticals remain necessary for the diagnosis of CAD because clinical use of current cardiac radiotracers is limited by their physical characteristics, such as decay mode, emission energy, and half-life. Thus, the use of a radioisotope that has proper characteristics and a proper half-life to develop myocardial perfusion agents could overcome these limitations. In this review, the current state of cardiac PET and a general overview of novel 18F or 68Ga-labeled radiotracers, including their radiosynthesis, in vivo characterization, and evaluation, are provided. The future perspectives are discussed in terms of their potential usefulness based on new image analysis methods and hybrid imaging.
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Affiliation(s)
- Dong-Yeon Kim
- Department of Nuclear Medicine, Chonnam National University Medical School and Hwasun Hospital, 322 Seoyang-ro Hwasun-eup, Hwasun-gun, Jeollanam-do 58128 Republic of Korea
| | - Sang-Geon Cho
- Department of Nuclear Medicine, Chonnam National University Medical School and Hwasun Hospital, 322 Seoyang-ro Hwasun-eup, Hwasun-gun, Jeollanam-do 58128 Republic of Korea
| | - Hee-Seung Bom
- Department of Nuclear Medicine, Chonnam National University Medical School and Hwasun Hospital, 322 Seoyang-ro Hwasun-eup, Hwasun-gun, Jeollanam-do 58128 Republic of Korea
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9
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Lai WF, Rogach AL, Wong WT. Chemistry and engineering of cyclodextrins for molecular imaging. Chem Soc Rev 2018; 46:6379-6419. [PMID: 28930330 DOI: 10.1039/c7cs00040e] [Citation(s) in RCA: 74] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Cyclodextrins (CDs) are naturally occurring cyclic oligosaccharides bearing a basket-shaped topology with an "inner-outer" amphiphilic character. The abundance of hydroxyl groups enables CDs to be functionalized with multiple targeting ligands and imaging elements. The imaging time, and the payload of different imaging elements, can be tuned by taking advantage of the commercial availability of CDs with different sizes of the cavity. This review aims to offer an outlook of the chemistry and engineering of CDs for the development of molecular probes. Complexation thermodynamics of CDs, and the corresponding implications for probe design, are also presented with examples demonstrating the structural and physiochemical roles played by CDs in the full ambit of molecular imaging. We hope that this review not only offers a synopsis of the current development of CD-based molecular probes, but can also facilitate translation of the incremental advancements from the laboratory to real biomedical applications by illuminating opportunities and challenges for future research.
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Affiliation(s)
- Wing-Fu Lai
- School of Pharmaceutical Sciences, Health Science Centre, Shenzhen University, Shenzhen, China.
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10
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Prokofieva DS, Abzianidze VV, Bogachenkov AS. Synthesis and Study on the Potential Anticancer Activity of Phosphinolinium-Type Halide Salts. RUSS J GEN CHEM+ 2017. [DOI: 10.1134/s107036321712043x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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11
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Inkster JAH, Zhang S, Akurathi V, Belanger A, Dubey S, Treves T, Packard AB. New chemical and radiochemical routes to [ 18F]Rho6G-DEG-F, a delocalized lipophilic cation for myocardial perfusion imaging with PET. MEDCHEMCOMM 2017; 8:1891-1896. [PMID: 29276578 DOI: 10.1039/c7md00326a] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
New chemical and radiochemical syntheses are described for the preparation of [18F]Rho6G-DEG-F, an 18F-labeled analogue of the fluoresecent dye rhodamine 6G, which has shown promise as myocardidal perfusion imaging agent. Tosylated precursors of [18F]Rho6G-DEG-F amenable to 18F-labeling were obtained either through a two-step synthesis from rhodamine 6G lactone (33% yield), or in one step from rhodamine 575 (64% yield), then purified by preparative C18 chromatography. Manual synthesis of [18F]Rho6G-DEG-F was achieved in a single radiochemical step from either the tosylate salt or the tosylate/formate double salt in DMSO under standard nucleophillic aliphatic 18F-fluorination conditions (K[18F]F/K2CO3/Kryptofix 2.2.2.). Incorporation of the [18F]F- was found to be satisfactory (≥34% by TLC), despite the protic character of the precursor molecules. [18F]Rho6G-DEG-F was manually synthesized in final decay-corrected radiochemical yields of 11-26% (tosylate salt) and 9-21% (tosylate/formate double salt). The protocol was transferred to an automated synthesis unit, where the product was obtained in 3-9% radiochemical yield (n=3) decay corrected to start-of-synthesis, >99% radiochemical purity, and a molar activity of 122-267 GBq/μmol (3.3-7.2 Ci/μmol).
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Affiliation(s)
- J A H Inkster
- Boston Children's Hospital, Division of Nuclear Medicine and Molecular Imaging, Boston, MA, 02115, USA.,Harvard Medical School, Boston, MA 02115, USA
| | - S Zhang
- Boston Children's Hospital, Division of Nuclear Medicine and Molecular Imaging, Boston, MA, 02115, USA.,Harvard Medical School, Boston, MA 02115, USA
| | - V Akurathi
- Boston Children's Hospital, Division of Nuclear Medicine and Molecular Imaging, Boston, MA, 02115, USA.,Harvard Medical School, Boston, MA 02115, USA
| | - A Belanger
- Brigham & Women's Hospital, Boston, MA 02115, USA
| | - S Dubey
- Brigham & Women's Hospital, Boston, MA 02115, USA
| | - T Treves
- Harvard Medical School, Boston, MA 02115, USA.,Brigham & Women's Hospital, Boston, MA 02115, USA
| | - A B Packard
- Boston Children's Hospital, Division of Nuclear Medicine and Molecular Imaging, Boston, MA, 02115, USA.,Harvard Medical School, Boston, MA 02115, USA
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12
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Chen S, Zhao Z, Zhang Y, Fang W, Lu J, Zhang X. Effect of methoxy group position on biological properties of 18 F–labeled benzyl triphenylphosphonium cations. Nucl Med Biol 2017; 49:16-23. [DOI: 10.1016/j.nucmedbio.2017.02.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Revised: 01/23/2017] [Accepted: 02/22/2017] [Indexed: 11/29/2022]
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13
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van de Weijer T, Paiman EHM, Lamb HJ. Cardiac metabolic imaging: current imaging modalities and future perspectives. J Appl Physiol (1985) 2017; 124:168-181. [PMID: 28473616 DOI: 10.1152/japplphysiol.01051.2016] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
In this review, current imaging techniques and their future perspectives in the field of cardiac metabolic imaging in humans are discussed. This includes a range of noninvasive imaging techniques, allowing a detailed investigation of cardiac metabolism in health and disease. The main imaging modalities discussed are magnetic resonance spectroscopy techniques for determination of metabolite content (triglycerides, glucose, ATP, phosphocreatine, and so on), MRI for myocardial perfusion, and single-photon emission computed tomography and positron emission tomography for quantitation of perfusion and substrate uptake.
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14
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van der Born D, Pees A, Poot AJ, Orru RVA, Windhorst AD, Vugts DJ. Fluorine-18 labelled building blocks for PET tracer synthesis. Chem Soc Rev 2017; 46:4709-4773. [DOI: 10.1039/c6cs00492j] [Citation(s) in RCA: 113] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
This review presents a comprehensive overview of the synthesis and application of fluorine-18 labelled building blocks since 2010.
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Affiliation(s)
- Dion van der Born
- Department of Radiology & Nuclear Medicine
- VU University Medical Center
- 1081 HV Amsterdam
- The Netherlands
| | - Anna Pees
- Department of Radiology & Nuclear Medicine
- VU University Medical Center
- 1081 HV Amsterdam
- The Netherlands
| | - Alex J. Poot
- Department of Radiology & Nuclear Medicine
- VU University Medical Center
- 1081 HV Amsterdam
- The Netherlands
| | - Romano V. A. Orru
- Department of Chemistry and Pharmaceutical Sciences and Amsterdam Institute for Molecules
- Medicines & Systems (AIMMS)
- VU University Amsterdam
- Amsterdam
- The Netherlands
| | - Albert D. Windhorst
- Department of Radiology & Nuclear Medicine
- VU University Medical Center
- 1081 HV Amsterdam
- The Netherlands
| | - Danielle J. Vugts
- Department of Radiology & Nuclear Medicine
- VU University Medical Center
- 1081 HV Amsterdam
- The Netherlands
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15
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Biological and structural studies of phosphonium ‘masked thiolate’ compounds. Eur J Med Chem 2017; 125:528-537. [DOI: 10.1016/j.ejmech.2016.08.025] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Revised: 08/11/2016] [Accepted: 08/12/2016] [Indexed: 01/09/2023]
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16
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Meyer JP, Adumeau P, Lewis JS, Zeglis BM. Click Chemistry and Radiochemistry: The First 10 Years. Bioconjug Chem 2016; 27:2791-2807. [PMID: 27787983 DOI: 10.1021/acs.bioconjchem.6b00561] [Citation(s) in RCA: 159] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The advent of click chemistry has had a profound influence on almost all branches of chemical science. This is particularly true of radiochemistry and the synthesis of agents for positron emission tomography (PET), single photon emission computed tomography (SPECT), and targeted radiotherapy. The selectivity, ease, rapidity, and modularity of click ligations make them nearly ideally suited for the construction of radiotracers, a process that often involves working with biomolecules in aqueous conditions with inexorably decaying radioisotopes. In the following pages, our goal is to provide a broad overview of the first 10 years of research at the intersection of click chemistry and radiochemistry. The discussion will focus on four areas that we believe underscore the critical advantages provided by click chemistry: (i) the use of prosthetic groups for radiolabeling reactions, (ii) the creation of coordination scaffolds for radiometals, (iii) the site-specific radiolabeling of proteins and peptides, and (iv) the development of strategies for in vivo pretargeting. Particular emphasis will be placed on the four most prevalent click reactions-the Cu-catalyzed azide-alkyne cycloaddition (CuAAC), the strain-promoted azide-alkyne cycloaddition (SPAAC), the inverse electron demand Diels-Alder reaction (IEDDA), and the Staudinger ligation-although less well-known click ligations will be discussed as well. Ultimately, it is our hope that this review will not only serve to educate readers but will also act as a springboard, inspiring synthetic chemists and radiochemists alike to harness click chemistry in even more innovative and ambitious ways as we embark upon the second decade of this fruitful collaboration.
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Affiliation(s)
| | - Pierre Adumeau
- Department of Chemistry, Hunter College of the City University of New York , 413 East 69th Street, New York, New York 10028, United States
| | - Jason S Lewis
- Department of Radiology, Weill Cornell Medical College , 520 East 70th Street, New York, New York 10065, United States
| | - Brian M Zeglis
- Department of Chemistry, Hunter College of the City University of New York , 413 East 69th Street, New York, New York 10028, United States.,Department of Radiology, Weill Cornell Medical College , 520 East 70th Street, New York, New York 10065, United States.,Ph.D. Program in Chemistry, The Graduate Center of the City University of New York , 365 5th Avenue, New York, New York 10016, United States
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Kelly J, Amor-Coarasa A, Nikolopoulou A, Kim D, Williams C, Ponnala S, Babich JW. Synthesis and pre-clinical evaluation of a new class of high-affinity 18F-labeled PSMA ligands for detection of prostate cancer by PET imaging. Eur J Nucl Med Mol Imaging 2016; 44:647-661. [PMID: 27847991 PMCID: PMC5323493 DOI: 10.1007/s00259-016-3556-5] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Accepted: 10/19/2016] [Indexed: 01/18/2023]
Abstract
Purpose Current clinical imaging of PSMA-positive prostate cancer by positron emission tomography (PET) mainly features 68Ga-labeled tracers, notably [68Ga]Ga-PSMA-HBED-CC. The longer half-life of fluorine-18 offers significant advantages over Ga-68, clinically and logistically. We aimed to develop high-affinity PSMA inhibitors labeled with fluorine-18 as alternative tracers for prostate cancer. Methods Six triazolylphenyl ureas and their alkyne precursors were synthesized from the Glu-urea-Lys PSMA binding moiety. PSMA affinity was determined in a competitive binding assay using LNCaP cells. The [18F]triazoles were isolated following a Cu(I)-catalyzed click reaction between the alkynes and [18F]fluoroethylazide. The 18F-labeled compounds were evaluated in nude mice bearing LNCaP tumors and compared to [68Ga]Ga-PSMA-HBED-CC and [18F]DCFPyL. Biodistribution studies of the two tracers with the highest imaged-derived tumor uptake and highest PSMA affinity were undertaken at 1 h, 2 h and 4 h post-injection (p.i.), and co-administration of PMPA was used to determine whether uptake was PSMA-specific. Results F-18-labeled triazolylphenyl ureas were prepared with a decay-corrected RCY of 20–40 %, >98 % radiochemical and chemical purity, and specific activity of up to 391 GBq/μmol. PSMA binding (IC50) ranged from 3–36 nM. The position of the triazole influenced tumor uptake (3 > 4 > 2), and direct conjugation of the triazole with the phenylurea moiety was preferred to insertion of a spacer group. Image-derived tumor uptake ranged from 6–14 %ID/g at 2 h p.i., the time of maximum tumor uptake; uptake of [68Ga]Ga-PSMA-HBED-CC and [18F]DCFPyL was 5–6 %ID/g at 1–3 h p.i., the time of maximum tumor uptake. Biodistribution studies of the two most promising compounds gave maximum tumor uptakes of 10.9 ± 1.0 % and 14.3 ± 2.5 %ID/g, respectively, as compared to 6.27 ± 1.44 %ID/g for [68Ga]Ga-PSMA-HBED-CC. Conclusions Six [18F]triazolylphenyl ureas were prepared in good radiochemical yield. Compounds showed PSMA-specific uptake in LNCaP tumors as high as 14 % ID/g, more than a 2-fold increase over [68Ga]Ga-PSMA-HBED-CC. The facile and high-yielding radiosynthesis of these 18F-labeled triazoles as well as their promising in vitro and in vivo characteristics make them worthy of clinical development for PET imaging of prostate cancer. Electronic supplementary material The online version of this article (doi:10.1007/s00259-016-3556-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- James Kelly
- Division of Radiopharmaceutical Sciences and Molecular Imaging Innovations Institute, Department of Radiology, Weill Cornell Medicine, Belfer Research Building, Room 1600, 413 East 69th Street, New York, NY, 10021, USA
| | - Alejandro Amor-Coarasa
- Division of Radiopharmaceutical Sciences and Molecular Imaging Innovations Institute, Department of Radiology, Weill Cornell Medicine, Belfer Research Building, Room 1600, 413 East 69th Street, New York, NY, 10021, USA
| | - Anastasia Nikolopoulou
- Division of Radiopharmaceutical Sciences and Molecular Imaging Innovations Institute, Department of Radiology, Weill Cornell Medicine, Belfer Research Building, Room 1600, 413 East 69th Street, New York, NY, 10021, USA.,Citigroup Biomedical Imaging Center, Weill Cornell Medicine, New York, NY, 10021, USA
| | - Dohyun Kim
- Citigroup Biomedical Imaging Center, Weill Cornell Medicine, New York, NY, 10021, USA
| | - Clarence Williams
- Division of Radiopharmaceutical Sciences and Molecular Imaging Innovations Institute, Department of Radiology, Weill Cornell Medicine, Belfer Research Building, Room 1600, 413 East 69th Street, New York, NY, 10021, USA
| | - Shashikanth Ponnala
- Division of Radiopharmaceutical Sciences and Molecular Imaging Innovations Institute, Department of Radiology, Weill Cornell Medicine, Belfer Research Building, Room 1600, 413 East 69th Street, New York, NY, 10021, USA
| | - John W Babich
- Division of Radiopharmaceutical Sciences and Molecular Imaging Innovations Institute, Department of Radiology, Weill Cornell Medicine, Belfer Research Building, Room 1600, 413 East 69th Street, New York, NY, 10021, USA. .,Citigroup Biomedical Imaging Center, Weill Cornell Medicine, New York, NY, 10021, USA. .,Meyer Cancer Center, Weill Cornell Medicine, New York, NY, 10021, USA.
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Chansaenpak K, Wang H, Wang M, Giglio B, Ma X, Yuan H, Hu S, Wu Z, Li Z. Synthesis and Evaluation of [(18) F]-Ammonium BODIPY Dyes as Potential Positron Emission Tomography Agents for Myocardial Perfusion Imaging. Chemistry 2016; 22:12122-9. [PMID: 27405398 DOI: 10.1002/chem.201601972] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Revised: 06/06/2016] [Indexed: 01/06/2023]
Abstract
Recently, we demonstrated the potential of a [(18) F]-trimethylammonium BODIPY dye for cardiac imaging. This is the first example of the use of the [(18) F]-ammonium BODIPY dye for positron emission tomography (PET) myocardial perfusion imaging (MPI). In this report, we extend our study to other ammonium BODIPY dyes with different nitrogen substituents. These novel ammonium BODIPY dyes were successfully prepared and radiolabeled by the SnCl4 -assisted (18) F-(19) F isotopic exchange method. The microPET results and the biodistribution data reveal that nitrogen substituent changes have a significant effect on the in vivo and pharmacological properties of the tracers. Of the novel [(18) F]-ammonium BODIPY dyes prepared in this work, the [(18) F]-dimethylethylammonium BODIPY is superior in terms of myocardium uptake and PET imaging contrast. These results support our hypothesis that the ammonium BODIPY dyes have a great potential for use as PET/optical dual-modality MPI probes.
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Affiliation(s)
- Kantapat Chansaenpak
- Biomedical Research Imaging Center, Department of Radiology, University of North Carolina, Chapel Hill, North Carolina, 27514, USA
| | - Hui Wang
- Biomedical Research Imaging Center, Department of Radiology, University of North Carolina, Chapel Hill, North Carolina, 27514, USA
| | - Mengzhe Wang
- Biomedical Research Imaging Center, Department of Radiology, University of North Carolina, Chapel Hill, North Carolina, 27514, USA
| | - Benjamin Giglio
- Biomedical Research Imaging Center, Department of Radiology, University of North Carolina, Chapel Hill, North Carolina, 27514, USA
| | - Xiaofeng Ma
- Biomedical Research Imaging Center, Department of Radiology, University of North Carolina, Chapel Hill, North Carolina, 27514, USA
| | - Hong Yuan
- Biomedical Research Imaging Center, Department of Radiology, University of North Carolina, Chapel Hill, North Carolina, 27514, USA
| | - Shuo Hu
- PET Center of Xiangya Hospital, Central South University, Changsha, 410008, China.
| | - Zhanhong Wu
- Biomedical Research Imaging Center, Department of Radiology, University of North Carolina, Chapel Hill, North Carolina, 27514, USA.
| | - Zibo Li
- Biomedical Research Imaging Center, Department of Radiology, University of North Carolina, Chapel Hill, North Carolina, 27514, USA
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Zhang Z, Jenni S, Zhang C, Merkens H, Lau J, Liu Z, Perrin DM, Bénard F, Lin KS. Synthesis and evaluation of 18F-trifluoroborate derivatives of triphenylphosphonium for myocardial perfusion imaging. Bioorg Med Chem Lett 2016; 26:1675-9. [DOI: 10.1016/j.bmcl.2016.02.062] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2016] [Revised: 02/18/2016] [Accepted: 02/19/2016] [Indexed: 12/30/2022]
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