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Qiu Z, Huang R, Wu Y, Li X, Sun C, Ma Y. Decoding the Structural Diversity: A New Horizon in Antimicrobial Prospecting and Mechanistic Investigation. Microb Drug Resist 2024; 30:254-272. [PMID: 38648550 DOI: 10.1089/mdr.2023.0232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/25/2024] Open
Abstract
The escalating crisis of antimicrobial resistance (AMR) underscores the urgent need for novel antimicrobials. One promising strategy is the exploration of structural diversity, as diverse structures can lead to diverse biological activities and mechanisms of action. This review delves into the role of structural diversity in antimicrobial discovery, highlighting its influence on factors such as target selectivity, binding affinity, pharmacokinetic properties, and the ability to overcome resistance mechanisms. We discuss various approaches for exploring structural diversity, including combinatorial chemistry, diversity-oriented synthesis, and natural product screening, and provide an overview of the common mechanisms of action of antimicrobials. We also describe techniques for investigating these mechanisms, such as genomics, proteomics, and structural biology. Despite significant progress, several challenges remain, including the synthesis of diverse compound libraries, the identification of active compounds, the elucidation of complex mechanisms of action, the emergence of AMR, and the translation of laboratory discoveries to clinical applications. However, emerging trends and technologies, such as artificial intelligence, high-throughput screening, next-generation sequencing, and open-source drug discovery, offer new avenues to overcome these challenges. Looking ahead, we envisage an exciting future for structural diversity-oriented antimicrobial discovery, with opportunities for expanding the chemical space, harnessing the power of nature, deepening our understanding of mechanisms of action, and moving toward personalized medicine and collaborative drug discovery. As we face the continued challenge of AMR, the exploration of structural diversity will be crucial in our search for new and effective antimicrobials.
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Affiliation(s)
- Ziying Qiu
- School of Pharmacy, Binzhou Medical University, Yantai, China
| | - Rongkun Huang
- School of Pharmacy, Binzhou Medical University, Yantai, China
| | - Yuxuan Wu
- School of Pharmacy, Binzhou Medical University, Yantai, China
| | - Xinghao Li
- School of Pharmacy, Binzhou Medical University, Yantai, China
| | - Chunyu Sun
- School of Pharmacy, Binzhou Medical University, Yantai, China
| | - Yunqi Ma
- School of Pharmacy, Binzhou Medical University, Yantai, China
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2
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José Besso M, Bitto V, Koi L, Wijaya Hadiwikarta W, Conde-Lopez C, Euler-Lange R, Bonrouhi M, Schneider K, Linge A, Krause M, Baumann M, Kurth I. Transcriptomic and epigenetic landscape of nimorazole-enhanced radiochemotherapy in head and neck cancer. Radiother Oncol 2024:110348. [PMID: 38823583 DOI: 10.1016/j.radonc.2024.110348] [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: 12/14/2023] [Revised: 04/27/2024] [Accepted: 05/20/2024] [Indexed: 06/03/2024]
Abstract
BACKGROUND Hypoxia remains a challenge for the therapeutic management of head and neck squamous cell carcinoma (HNSCC). The combination of radiotherapy with nimorazole has shown treatment benefit in HNSCC, but the precise underlying molecular mechanisms remain unclear. PURPOSE To assess and to characterize the transcriptomic/epigenetic landscape of HNSCC tumor models showing differential therapeutic response to fractionated radiochemotherapy (RCTx) combined with nimorazole. MATERIALS/METHODS Bulk RNA-sequencing and DNA methylation experiments were conducted using untreated and treated HNSCC xenografts after 10 fractions of RCTx with and without nimorazole. These tumor models (FaDu, SAS, Cal33, SAT and UT-SCC-45) previously showed a heterogeneous response to RCTx with nimorazole. The prognostic impact of candidate genes was assessed using clinical and gene expression data from HNSCC patients treated with primary RCTx within the DKTK-ROG. RESULTS Nimorazole responder and non-responder tumor models showed no differences in hypoxia gene signatures However, non-responder models showed upregulation of metabolic pathways. From that, a subset of 15 differentially expressed genes stratified HNSCC patients into low and high-risk groups with distinct outcome. CONCLUSION In the present study, we found that nimorazole non-responder models were characterized by upregulation of genes involved in Retinol metabolism and xenobiotic metabolic process pathways, which might contribute to identify mechanisms of resistance to nitroimidazole compounds and potentially expand the repertoire of therapeutic options to treat HNSCC.
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Affiliation(s)
- María José Besso
- German Cancer Research Center (DKFZ) Heidelberg, Division of Radiooncology Radiobiology, Germany.
| | - Verena Bitto
- German Cancer Research Center (DKFZ) Heidelberg, Division of Radiooncology Radiobiology, Germany; German Cancer Research Center (DKFZ) Heidelberg, Division of Applied Bioinformatics, Germany; Faculty for Mathematics and Computer Science, Heidelberg University, Germany; HIDSS4Health - Helmholtz Information and Data Science School for Health, Karlsruhe/Heidelberg, Germany
| | - Lydia Koi
- OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden - Rossendorf, Dresden, Germany; Department of Radiotherapy and Radiation Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany; Helmholtz-Zentrum Dresden - Rossendorf, Institute of Radiooncology - OncoRay, Dresden, Germany
| | - Wahyu Wijaya Hadiwikarta
- German Cancer Research Center (DKFZ) Heidelberg, Division of Radiooncology Radiobiology, Germany; National Center for Radiation Research in Oncology (NCRO), Heidelberg Institute for Radiation Oncology (HIRO), Heidelberg, Germany
| | - Cristina Conde-Lopez
- German Cancer Research Center (DKFZ) Heidelberg, Division of Radiooncology Radiobiology, Germany
| | - Rosemarie Euler-Lange
- German Cancer Research Center (DKFZ) Heidelberg, Division of Radiooncology Radiobiology, Germany
| | - Mahnaz Bonrouhi
- German Cancer Research Center (DKFZ) Heidelberg, Division of Radiooncology Radiobiology, Germany
| | - Karolin Schneider
- German Cancer Research Center (DKFZ) Heidelberg, Division of Radiooncology Radiobiology, Germany
| | - Annett Linge
- OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden - Rossendorf, Dresden, Germany; Department of Radiotherapy and Radiation Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany; German Cancer Research Center (DKFZ), and German Cancer Consortium (DKTK), Partner Site Dresden, Heidelberg, Germany; National Center for Tumor Diseases (NCT), Partner Site Dresden, Germany; Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, and Helmholtz Association / Helmholtz-Zentrum Dresden Rossendorf (HZDR), Dresden, Germany
| | - Mechthild Krause
- OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden - Rossendorf, Dresden, Germany; Department of Radiotherapy and Radiation Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany; Helmholtz-Zentrum Dresden - Rossendorf, Institute of Radiooncology - OncoRay, Dresden, Germany; German Cancer Research Center (DKFZ), and German Cancer Consortium (DKTK), Partner Site Dresden, Heidelberg, Germany; National Center for Tumor Diseases (NCT), Partner Site Dresden, Germany; Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, and Helmholtz Association / Helmholtz-Zentrum Dresden Rossendorf (HZDR), Dresden, Germany
| | - Michael Baumann
- German Cancer Research Center (DKFZ) Heidelberg, Division of Radiooncology Radiobiology, Germany; OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden - Rossendorf, Dresden, Germany; German Cancer Research Center (DKFZ), and German Cancer Consortium (DKTK), Core Center Heidelberg, Heidelberg, Germany; National Center for Radiation Research in Oncology (NCRO), Heidelberg Institute for Radiation Oncology (HIRO), Heidelberg, Germany
| | - Ina Kurth
- German Cancer Research Center (DKFZ) Heidelberg, Division of Radiooncology Radiobiology, Germany; German Cancer Research Center (DKFZ), and German Cancer Consortium (DKTK), Core Center Heidelberg, Heidelberg, Germany; National Center for Radiation Research in Oncology (NCRO), Heidelberg Institute for Radiation Oncology (HIRO), Heidelberg, Germany
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3
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Major benznidazole metabolites in patients treated for Chagas disease: Mass spectrometry-based identification, structural analysis and detoxification pathways. Toxicol Lett 2023; 377:71-82. [PMID: 36775077 DOI: 10.1016/j.toxlet.2023.02.001] [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: 10/14/2022] [Revised: 01/22/2023] [Accepted: 02/08/2023] [Indexed: 02/12/2023]
Abstract
Benznidazole is the drug of choice for the treatment of Chagas disease, but its metabolism in humans is unclear. Here, we identified and characterized the major benznidazole metabolites and their biosynthetic mechanisms in humans by analyzing the ionic profiles of urine samples from patients and untreated donors through reversed-phase UHPLC-ESI-QTOF-MS and UHPLC-ESI-QqLIT-MS. A strategy for simultaneous detection and fragmentation of characteristic positive and negative ions was employed using information-dependent acquisitions (IDA). Selected precursor ions, neutral losses, and MS3 experiments complemented the study. A total of six phase-I and ten phase-II metabolites were identified and structurally characterized in urine of benznidazole-treated patients. Based on creatinine-corrected ion intensities, nitroreduction to amino-benznidazole (M1) and its subsequent N-glucuronidation to M5 were the main metabolic pathways, followed by imidazole-ring cleavage, oxidations, and cysteine conjugations. This extensive exploration of benznidazole metabolites revealed potentially toxic structures in the form of glucuronides and glutathione derivatives, which may be associated with recurrent treatment adverse events; this possibility warrants further exploration in future clinical trials. Incorporation of this knowledge of the benznidazole metabolic profile into clinical pharmacology trials could lead to improved treatments, facilitate the study of possible drug-drug interactions, and even mitigation of adverse drug reactions.
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Value of whole-body dynamic 18F-FMISO PET/CT Patlak multi-parameter imaging for evaluating the early radiosensitizing effect of oleanolic acid on C6 rat gliomas. Cancer Chemother Pharmacol 2023; 91:133-141. [PMID: 36565309 DOI: 10.1007/s00280-022-04502-7] [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: 09/26/2022] [Accepted: 12/19/2022] [Indexed: 12/25/2022]
Abstract
The purpose of this study was to investigate the value of tumour-to-muscle (T/M) ratios and Patlak Ki images extracted from whole-body dynamic 18F-fluoromisonidazole (FMISO) PET/CT Patlak multi-parameter imaging for evaluating the early radiosensitizing effect of oleanolic acid (OA). Twenty-four rats with C6 gliomas were divided into 4 groups and treated with OA (group B), radiotherapy (group C), both (group D) or neither (group A). Whole-body dynamic 18F-FMISO PET/CT scans were performed for 120 min before treatment and 24 h following the treatment course. The tumour samples were dissected for hematoxylin and eosin staining, and HIF-1α, Ki-67 and GLUT-1 immunohistochemical staining. PET images were analysed using kinetic modelling (Patlak Ki) and static analysis (T/M ratios), and correlated with immunohistochemical results. The changes in T/M ratios, Ki values and tumour volume before treatment and 24 h following the treatment course were compared, and the survival time of tumour-bearing rats was recorded. Kaplan-Meier analysis showed that OA combined with radiotherapy can inhibit tumour growth and prolong the survival time of tumour-bearing rats. Whole-body dynamic 18F-FMISO PET/CT showed that the Ki values in group D were significantly lower than those in group C, whilst there was no significant difference in T/M ratios between groups C and D. The Pearson correlation coefficient analysis showed that Ki values were significantly related to immunohistochemical results. Our study suggests that Patlak Ki images may add value to PET/CT static images for evaluating the early radio-sensitizing effect of OA.
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5
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Ferda J, Ferdová E, Vítovec M, Glanc D, Mírka H. The imaging of the hypoxic microenvironment in tumorous tissue using PET/CT and PET/MRI. Eur J Radiol 2022; 154:110458. [DOI: 10.1016/j.ejrad.2022.110458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Accepted: 07/25/2022] [Indexed: 11/03/2022]
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6
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Yin L, Zhan J, Liao H, Qiu W, Hou W, Li S, Zhang J. Novel vandetanib derivative inhibited proliferation and promoted apoptosis of cancer cells under normoxia and hypoxia. Eur J Pharmacol 2022; 922:174907. [DOI: 10.1016/j.ejphar.2022.174907] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Revised: 03/17/2022] [Accepted: 03/17/2022] [Indexed: 11/29/2022]
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7
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Brender JR, Saida Y, Devasahayam N, Krishna MC, Kishimoto S. Hypoxia Imaging As a Guide for Hypoxia-Modulated and Hypoxia-Activated Therapy. Antioxid Redox Signal 2022; 36:144-159. [PMID: 34428981 PMCID: PMC8856011 DOI: 10.1089/ars.2021.0176] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Significance: Oxygen imaging techniques, which can probe the spatiotemporal heterogeneity of tumor oxygenation, could be of significant clinical utility in radiation treatment planning and in evaluating the effectiveness of hypoxia-activated prodrugs. To fulfill these goals, oxygen imaging techniques should be noninvasive, quantitative, and capable of serial imaging, as well as having sufficient temporal resolution to detect the dynamics of tumor oxygenation to distinguish regions of chronic and acute hypoxia. Recent Advances: No current technique meets all these requirements, although all have strengths in certain areas. The current status of positron emission tomography (PET)-based hypoxia imaging, oxygen-enhanced magnetic resonance imaging (MRI), 19F MRI, and electron paramagnetic resonance (EPR) oximetry are reviewed along with their strengths and weaknesses for planning hypoxia-guided, intensity-modulated radiation therapy and detecting treatment response for hypoxia-targeted prodrugs. Critical Issues: Spatial and temporal resolution emerges as a major concern for these areas along with specificity and quantitative response. Although multiple oxygen imaging techniques have reached the investigative stage, clinical trials to test the therapeutic effectiveness of hypoxia imaging have been limited. Future Directions: Imaging elements of the redox environment besides oxygen by EPR and hyperpolarized MRI may have a significant impact on our understanding of the basic biology of the reactive oxygen species response and may extend treatment possibilities.
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Affiliation(s)
- Jeffrey R Brender
- Radiation Biology Branch, Center for Cancer Research, National Institutes of Health, Bethesda, Maryland, USA
| | - Yu Saida
- Radiation Biology Branch, Center for Cancer Research, National Institutes of Health, Bethesda, Maryland, USA
| | - Nallathamby Devasahayam
- Radiation Biology Branch, Center for Cancer Research, National Institutes of Health, Bethesda, Maryland, USA
| | - Murali C Krishna
- Radiation Biology Branch, Center for Cancer Research, National Institutes of Health, Bethesda, Maryland, USA
| | - Shun Kishimoto
- Radiation Biology Branch, Center for Cancer Research, National Institutes of Health, Bethesda, Maryland, USA
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8
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Huang Y, Fan J, Li Y, Fu S, Chen Y, Wu J. Imaging of Tumor Hypoxia With Radionuclide-Labeled Tracers for PET. Front Oncol 2021; 11:731503. [PMID: 34557414 PMCID: PMC8454408 DOI: 10.3389/fonc.2021.731503] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2021] [Accepted: 08/19/2021] [Indexed: 01/27/2023] Open
Abstract
The hypoxic state in a solid tumor refers to the internal hypoxic environment that appears as the tumor volume increases (the maximum radius exceeds 180-200 microns). This state can promote angiogenesis, destroy the balance of the cell’s internal environment, and lead to resistance to radiotherapy and chemotherapy, as well as poor prognostic factors such as metastasis and recurrence. Therefore, accurate quantification, mapping, and monitoring of hypoxia, targeted therapy, and improvement of tumor hypoxia are of great significance for tumor treatment and improving patient survival. Despite many years of development, PET-based hypoxia imaging is still the most widely used evaluation method. This article provides a comprehensive overview of tumor hypoxia imaging using radionuclide-labeled PET tracers. We introduced the mechanism of tumor hypoxia and the reasons leading to the poor prognosis, and more comprehensively included the past, recent and ongoing studies of PET radiotracers for tumor hypoxia imaging. At the same time, the advantages and disadvantages of mainstream methods for detecting tumor hypoxia are summarized.
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Affiliation(s)
- Yuan Huang
- Department of Oncology, The Affiliated Hospital of Southwest Medical University, Luzhou, China
| | - Junying Fan
- Department of Oncology, The Affiliated Hospital of Southwest Medical University, Luzhou, China
| | - Yi Li
- Department of Oncology, The Affiliated Hospital of Southwest Medical University, Luzhou, China
| | - Shaozhi Fu
- Department of Oncology, The Affiliated Hospital of Southwest Medical University, Luzhou, China.,Department of Oncology, Academician (Expert) Workstation of Sichuan Province, Luzhou, China
| | - Yue Chen
- Department of Oncology, Academician (Expert) Workstation of Sichuan Province, Luzhou, China.,Nuclear Medicine and Molecular Imaging key Laboratory of Sichuan Province, Department of Nuclear Medicine, The Affiliated Hospital of Southwest Medical University, Luzhou, China
| | - Jingbo Wu
- Department of Oncology, The Affiliated Hospital of Southwest Medical University, Luzhou, China.,Department of Oncology, Academician (Expert) Workstation of Sichuan Province, Luzhou, China
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9
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Florea A, Mottaghy FM, Bauwens M. Molecular Imaging of Angiogenesis in Oncology: Current Preclinical and Clinical Status. Int J Mol Sci 2021; 22:5544. [PMID: 34073992 PMCID: PMC8197399 DOI: 10.3390/ijms22115544] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Revised: 05/17/2021] [Accepted: 05/20/2021] [Indexed: 12/11/2022] Open
Abstract
Angiogenesis is an active process, regulating new vessel growth, and is crucial for the survival and growth of tumours next to other complex factors in the tumour microenvironment. We present possible molecular imaging approaches for tumour vascularisation and vitality, focusing on radiopharmaceuticals (tracers). Molecular imaging in general has become an integrated part of cancer therapy, by bringing relevant insights on tumour angiogenic status. After a structured PubMed search, the resulting publication list was screened for oncology related publications in animals and humans, disregarding any cardiovascular findings. The tracers identified can be subdivided into direct targeting of angiogenesis (i.e., vascular endothelial growth factor, laminin, and fibronectin) and indirect targeting (i.e., glucose metabolism, hypoxia, and matrix metallo-proteases, PSMA). Presenting pre-clinical and clinical data of most tracers proposed in the literature, the indirect targeting agents are not 1:1 correlated with angiogenesis factors but do have a strong prognostic power in a clinical setting, while direct targeting agents show most potential and specificity for assessing tumour vascularisation and vitality. Within the direct agents, the combination of multiple targeting tracers into one agent (multimers) seems most promising. This review demonstrates the present clinical applicability of indirect agents, but also the need for more extensive research in the field of direct targeting of angiogenesis in oncology. Although there is currently no direct tracer that can be singled out, the RGD tracer family seems to show the highest potential therefore we expect one of them to enter the clinical routine.
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Affiliation(s)
- Alexandru Florea
- Department of Nuclear Medicine, University Hospital RWTH Aachen, 52074 Aachen, Germany; (A.F.); (M.B.)
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center, 6229HX Maastricht, The Netherlands
- School for Cardiovascular Diseases (CARIM), Maastricht University, 6229HX Maastricht, The Netherlands
| | - Felix M. Mottaghy
- Department of Nuclear Medicine, University Hospital RWTH Aachen, 52074 Aachen, Germany; (A.F.); (M.B.)
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center, 6229HX Maastricht, The Netherlands
- School for Cardiovascular Diseases (CARIM), Maastricht University, 6229HX Maastricht, The Netherlands
- School of Nutrition and Translational Research in Metabolism (NUTRIM), Maastricht University, 6229HX Maastricht, The Netherlands
| | - Matthias Bauwens
- Department of Nuclear Medicine, University Hospital RWTH Aachen, 52074 Aachen, Germany; (A.F.); (M.B.)
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center, 6229HX Maastricht, The Netherlands
- School of Nutrition and Translational Research in Metabolism (NUTRIM), Maastricht University, 6229HX Maastricht, The Netherlands
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Shimizu Y, Nakai Y, Watanabe H, Iikuni S, Ono M, Saji H, Kuge Y, Saga T, Nakamoto Y. Increased [ 18F]FMISO accumulation under hypoxia by multidrug-resistant protein 1 inhibitors. EJNMMI Res 2021; 11:9. [PMID: 33492449 PMCID: PMC7835267 DOI: 10.1186/s13550-021-00752-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2020] [Accepted: 01/11/2021] [Indexed: 11/30/2022] Open
Abstract
Background [18F]Fluoromisonidazole ([18F]FMISO) is a PET imaging probe widely used for the detection of hypoxia. We previously reported that [18F]FMISO is metabolized to the glutathione conjugate of the reduced form in hypoxic cells. In addition, we found that the [18F]FMISO uptake level varied depending on the cellular glutathione conjugation and excretion ability such as enzyme activity of glutathione-S-transferase and expression levels of multidrug resistance-associated protein 1 (MRP1, an efflux transporter), in addition to the cellular hypoxic state. In this study, we evaluated whether MRP1 activity affected [18F]FMISO PET imaging. Methods FaDu human pharyngeal squamous cell carcinoma cells were pretreated with MRP1 inhibitors (cyclosporine A, lapatinib, or MK-571) for 1 h, incubated with [18F]FMISO for 4 h under hypoxia, and their radioactivity was then measured. FaDu tumor-bearing mice were intravenously injected with [18F]FMISO, and PET/CT images were acquired at 4 h post-injection (1st PET scan). Two days later, the same mice were pretreated with MRP1 inhibitors (cyclosporine A, lapatinib, or MK-571) for 1 h, and PET/CT images were acquired (2nd PET scan). Results FaDu cells pretreated with MRP1 inhibitors exhibited significantly higher radioactivity than those without inhibitor treatment (cyclosporine A: 6.91 ± 0.27, lapatinib: 10.03 ± 0.47, MK-571: 10.15 ± 0.44%dose/mg protein, p < 0.01). In the in vivo PET study, the SUVmean ratio in tumors [calculated as after treatment (2nd PET scan)/before treatment of MRP1 inhibitors (1st PET scan)] of the mice treated with MRP1 inhibitors was significantly higher than those of control mice (cyclosporine A: 2.6 ± 0.7, lapatinib: 2.2 ± 0.7, MK-571: 2.2 ± 0.7, control: 1.2 ± 0.2, p < 0.05). Conclusion In this study, we revealed that MRP1 inhibitors increase [18F]FMISO accumulation in hypoxic cells. This suggests that [18F]FMISO-PET imaging is affected by MRP1 inhibitors independent of the hypoxic state.
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Affiliation(s)
- Yoichi Shimizu
- Department of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University, 54 Shogoinkawahara-cho, Sakyo-Ku, Kyoto, 606-8507, Japan. .,Department of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto, 606-8501, Japan.
| | - Yukihiro Nakai
- Department of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto, 606-8501, Japan
| | - Hiroyuki Watanabe
- Department of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto, 606-8501, Japan
| | - Shimpei Iikuni
- Department of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto, 606-8501, Japan
| | - Masahiro Ono
- Department of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto, 606-8501, Japan
| | - Hideo Saji
- Department of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto, 606-8501, Japan
| | - Yuji Kuge
- Central Institute of Isotope Science, Hokkaido University, Sapporo, 060-0815, Japan
| | - Tsuneo Saga
- Department of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University, 54 Shogoinkawahara-cho, Sakyo-Ku, Kyoto, 606-8507, Japan
| | - Yuji Nakamoto
- Department of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University, 54 Shogoinkawahara-cho, Sakyo-Ku, Kyoto, 606-8507, Japan
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Abstract
Over the last few years, cancer immunotherapy experienced tremendous developments and it is nowadays considered a promising strategy against many types of cancer. However, the exclusion of lymphocytes from the tumor nest is a common phenomenon that limits the efficiency of immunotherapy in solid tumors. Despite several mechanisms proposed during the years to explain the immune excluded phenotype, at present, there is no integrated understanding about the role played by different models of immune exclusion in human cancers. Hypoxia is a hallmark of most solid tumors and, being a multifaceted and complex condition, shapes in a unique way the tumor microenvironment, affecting gene transcription and chromatin remodeling. In this review, we speculate about an upstream role for hypoxia as a common biological determinant of immune exclusion in solid tumors. We also discuss the current state of ex vivo and in vivo imaging of hypoxic determinants in relation to T cell distribution that could mechanisms of immune exclusion and discover functional-morphological tumor features that could support clinical monitoring.
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Gelardi F, Kirienko M, Sollini M. Climbing the steps of the evidence-based medicine pyramid: highlights from Annals of Nuclear Medicine 2019. Eur J Nucl Med Mol Imaging 2020; 48:1293-1301. [PMID: 33150459 DOI: 10.1007/s00259-020-05073-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2020] [Accepted: 10/12/2020] [Indexed: 12/17/2022]
Abstract
We aimed to provide an overview on research path in nuclear medicine climbing the steps of the Evidence-Based Medicine (EBM) pyramid using review of 14 subjectively selected papers out of 111 published in the Annals of Nuclear Medicine during January-December 2019. Following the structure of the EBM hierarchy, we chose at least one study for each step of the pyramid from the basis (pre-clinical research, expert opinion, case report and case series), to the middle (case-control and cohort studies, randomised controlled trials), towards the top (meta-analyses and systematic reviews). Additionally, we collected information on the promoter of each included study: investigator-initiated trials (IITs) vs industry-sponsored trials (ISTs). We found that pre-clinical studies are primarily focused on the development of novel molecular targets in cancer, with promising results. At the same time, clinical investigations deal with cardiological, neurological, infectious and oncological applications using both SPECT and PET modalities. Additionally, radionuclide therapy gained interest and is experiencing comprehensive clinical implementation. Our overview confirms the current central role of IITs as compared with ISTs. Challenges and future directions in Nuclear Medicine research are discussed.
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Affiliation(s)
- Fabrizia Gelardi
- Humanitas University, Pieve Emanuele, Milan, Italy.,Humanitas Clinical and Research Center - IRCCS, Rozzano, Milan, Italy
| | - Margarita Kirienko
- Nuclear Medicine, Fondazione IRCCS Istituto Nazionale dei Tumori, Via Venezian 1, 20133, Milan, Italy.
| | - Martina Sollini
- Humanitas University, Pieve Emanuele, Milan, Italy.,Humanitas Clinical and Research Center - IRCCS, Rozzano, Milan, Italy
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A Novel PET Probe "[ 18F]DiFA" Accumulates in Hypoxic Region via Glutathione Conjugation Following Reductive Metabolism. Mol Imaging Biol 2019; 21:122-129. [PMID: 29845425 DOI: 10.1007/s11307-018-1214-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
PURPOSE Hypoxia in tumor has close relationship with angiogenesis and tumor progression. Previously, we developed 2,2-dihydroxymethyl-3-[18F]fluoropropyl-2-nitroimidazole ([18F]DiFA) as a novel positron emission tomography (PET) probe for diagnosis of hypoxia. In this study, we elucidated whether the accumulation of [18F]DiFA in cells is dependent on the hypoxic state and revealed how [18F]DiFA accumulates in hypoxic cells in combination with imaging mass spectrometry (IMS). PROCEDURES FaDu human head and neck cancer cells were treated with [18F]DiFA and then incubated under normoxia (21% O2) or hypoxia (1% O2) for 2 h. The cells were extracted using methanol, and the radioactivities of the precipitates (macromolecule fraction) and supernatants (low-molecular-weight fraction) were measured. FaDu-bearing mice were injected intravenously with [18F]DiFA and with pimonidazole 1 h later. The tumors were excised 2 h after the injection of [18F]DiFA. Autoradiography, IMS, and immunohistochemical (IHC) staining for pimonidazole were performed with serial tumor sections. RESULTS In the in vitro study, the radioactivity of FaDu cells was significantly higher under hypoxia than that under normoxia (0.53 ± 0.02 vs. 0.27 ± 0.02 %dose/mg protein, p < 0.05). The radioactivity of the low-molecular-weight fraction was 66.3 ± 0.6% in the hypoxic cell. In the in vivo study, [18F]DiFA accumulated in the tumor tissues existed mainly as low-molecular-weight compounds (90.4 ± 0.9%). In addition, the glutathione conjugate of reductive DiFA metabolite (amino-DiFA-GS) existed in tumor tissues revealed by the IMS study, and the distribution pattern of amino-DiFA-GS was very similar to that of the radioactivity and the positive staining area of pimonidazole. CONCLUSIONS Our results suggest that [18F]DiFA undergoes the glutathione conjugation reaction following reductive metabolism in hypoxic cells, which leads hypoxia-specific PET imaging with [18F]DiFA.
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The Roles of Hypoxia Imaging Using 18F-Fluoromisonidazole Positron Emission Tomography in Glioma Treatment. J Clin Med 2019; 8:jcm8081088. [PMID: 31344848 PMCID: PMC6723061 DOI: 10.3390/jcm8081088] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2019] [Revised: 07/16/2019] [Accepted: 07/22/2019] [Indexed: 12/14/2022] Open
Abstract
Glioma is the most common malignant brain tumor. Hypoxia is closely related to the malignancy of gliomas, and positron emission tomography (PET) can noninvasively visualize the degree and the expansion of hypoxia. Currently, 18F-fluoromisonidazole (FMISO) is the most common radiotracer for hypoxia imaging. The clinical usefulness of FMISO PET has been established; it can distinguish glioblastomas from lower-grade gliomas and can predict the microenvironment of a tumor, including necrosis, vascularization, and permeability. FMISO PET provides prognostic information, including survival and treatment response information. Because hypoxia decreases a tumor’s sensitivity to radiation therapy, dose escalation to an FMISO-positive volume is an attractive strategy. Although this idea is not new, an insufficient amount of evidence has been obtained regarding this concept. New tracers for hypoxia imaging such as 18F-DiFA are being tested. In the future, hypoxia imaging will play an important role in glioma management.
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Watanabe S, Shiga T, Hirata K, Magota K, Okamoto S, Toyonaga T, Higashikawa K, Yasui H, Kobayashi J, Nishijima KI, Iseki K, Matsumoto H, Kuge Y, Tamaki N. Biodistribution and radiation dosimetry of the novel hypoxia PET probe [ 18F]DiFA and comparison with [ 18F]FMISO. EJNMMI Res 2019; 9:60. [PMID: 31278504 PMCID: PMC6611855 DOI: 10.1186/s13550-019-0525-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Accepted: 06/05/2019] [Indexed: 02/03/2023] Open
Abstract
Background To facilitate hypoxia imaging in a clinical setting, we developed 1-(2,2-dihydroxymethyl-3-[18F]-fluoropropyl)-2-nitroimidazole ([18F]DiFA) as a new tracer that targets tumor hypoxia with its lower lipophilicity and efficient radiosynthesis. Here, we evaluated the radiation dosage, biodistribution, human safety, tolerability, and early elimination after the injection of [18F]DiFA in healthy subjects, and we performed a preliminary clinical study of patients with malignant tumors in a comparison with [18F]fluoromisonidazole ([18F]FMISO). Results The single administration of [18F]DiFA in 8 healthy male adults caused neither adverse events nor abnormal clinical findings. Dynamic and sequential whole-body scans showed that [18F]DiFA was rapidly cleared from all of the organs via the hepatobiliary and urinary systems. The whole-body mean effective dose of [18F]DiFA estimated by using the medical internal radiation dose (MIRD) schema with organ level internal dose assessment/exponential modeling (OLINDA/EXM) computer software 1.1 was 14.4 ± 0.7 μSv/MBq. Among the organs, the urinary bladder received the largest absorbed dose (94.7 ± 13.6 μSv/MBq). The mean absorbed doses of the other organs were equal to or less than those from other hypoxia tracers. The excretion of radioactivity via the urinary system was very rapid, reaching 86.4 ± 7.1% of the administered dose. For the preliminary clinical study, seven patients were subjected to [18F]FMISO and [18F]DiFA positron emission tomography (PET) at 48-h intervals to compare the two tracers’ diagnostic ability for tumor hypoxia. The results of the tumor hypoxia evaluation by [18F]DiFA PET at 1 h and 2 h were not significantly different from those obtained with [18F]FMISO PET at 4 h ([18F]DiFA at 1 h, p = 0.32; [18F]DiFA at 2 h, p = 0.08). Moreover, [18F]DiFA PET at both 1 h (k = 0.68) and 2 h (k = 1.00) showed better inter-observer reproducibility than [18F]FMISO PET at 4 h (k = 0.59). Conclusion [18F]DiFA is well tolerated, and its radiation dose is comparable to those of other hypoxia tracers. [18F]DiFA is very rapidly cleared via the urinary system. [18F]DiFA PET generated comparable images to [18F]FMISO PET in hypoxia imaging with shorter waiting time, demonstrating the promising potential of [18F]DiFA PET for hypoxia imaging and for a multicenter trial. Electronic supplementary material The online version of this article (10.1186/s13550-019-0525-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Shiro Watanabe
- Department of Nuclear Medicine, Graduate School of Medicine, Hokkaido University, Kita-15, Nishi-7, Kita-ku, Sapporo, 060-8638, Japan
| | - Tohru Shiga
- Department of Nuclear Medicine, Graduate School of Medicine, Hokkaido University, Kita-15, Nishi-7, Kita-ku, Sapporo, 060-8638, Japan.
| | - Kenji Hirata
- Department of Nuclear Medicine, Graduate School of Medicine, Hokkaido University, Kita-15, Nishi-7, Kita-ku, Sapporo, 060-8638, Japan
| | - Keiichi Magota
- Division of Medical Imaging and Technology, Hokkaido University Hospital, Kita-14, Nishi-5, Kita-ku, Sapporo, 060-8648, Japan
| | - Shozo Okamoto
- Department of Nuclear Medicine, Graduate School of Medicine, Hokkaido University, Kita-15, Nishi-7, Kita-ku, Sapporo, 060-8638, Japan.,Department of Radiology, Obihiro Kosei Hospital, West 14 South 10-1, Obihiro, 080-0024, Japan
| | - Takuya Toyonaga
- Department of Nuclear Medicine, Graduate School of Medicine, Hokkaido University, Kita-15, Nishi-7, Kita-ku, Sapporo, 060-8638, Japan
| | - Kei Higashikawa
- Central Institute of Isotope Science, Hokkaido University, Kita-15, Nishi-7, Kita-ku, Sapporo, 060-8638, Japan
| | - Hironobu Yasui
- Central Institute of Isotope Science, Hokkaido University, Kita-15, Nishi-7, Kita-ku, Sapporo, 060-8638, Japan
| | - Jun Kobayashi
- Department of Pharmacy, Hokkaido University Hospital, Kita-14, Nishi-5, Kita-ku, Sapporo, 060-8648, Japan
| | - Ken-Ichi Nishijima
- Central Institute of Isotope Science, Hokkaido University, Kita-15, Nishi-7, Kita-ku, Sapporo, 060-8638, Japan.,Advanced Clinical Research Center, Fukushima Global Medical Science Center, Fukushima Medical University, 1 Hikariga-oka, Fukushima, 960-1295, Japan
| | - Ken Iseki
- Department of Pharmacy, Hokkaido University Hospital, Kita-14, Nishi-5, Kita-ku, Sapporo, 060-8648, Japan.,Faculty of Pharmaceutical Sciences, Kita-14, Nishi-5, Kita-ku, Sapporo, 060-8648, Japan
| | - Hiroki Matsumoto
- Research Centre, Nihon Medi-Physics Co., Ltd., 3-1 Kitasode, Sodegaura, 299-0266, Japan
| | - Yuji Kuge
- Department of Nuclear Medicine, Graduate School of Medicine, Hokkaido University, Kita-15, Nishi-7, Kita-ku, Sapporo, 060-8638, Japan.,Central Institute of Isotope Science, Hokkaido University, Kita-15, Nishi-7, Kita-ku, Sapporo, 060-8638, Japan
| | - Nagara Tamaki
- Department of Nuclear Medicine, Graduate School of Medicine, Hokkaido University, Kita-15, Nishi-7, Kita-ku, Sapporo, 060-8638, Japan.,Department of Radiology, Kyoto Prefectural University of Medicine, Kajii-cho, Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto, 602-8566, Japan
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Zhao S, Yu W, Ukon N, Tan C, Nishijima KI, Shimizu Y, Higashikawa K, Shiga T, Yamashita H, Tamaki N, Kuge Y. Elimination of tumor hypoxia by eribulin demonstrated by 18F-FMISO hypoxia imaging in human tumor xenograft models. EJNMMI Res 2019; 9:51. [PMID: 31161539 PMCID: PMC6546772 DOI: 10.1186/s13550-019-0521-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Accepted: 05/27/2019] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Eribulin, an inhibitor of microtubule dynamics, shows antitumor potency against a variety of solid cancers through its antivascular activity and remodeling of tumor vasculature. 18F-Fluoromisonidazole (18F-FMISO) is the most widely used PET probe for imaging tumor hypoxia. In this study, we utilized 18F-FMISO to clarify the effects of eribulin on the tumor hypoxic condition in comparison with histological findings. MATERIAL AND METHODS Mice bearing a human cancer cell xenograft were intraperitoneally administered a single dose of eribulin (0.3 or 1.0 mg/kg) or saline. Three days after the treatment, mice were injected with 18F-FMISO and pimonidazole (hypoxia marker for immunohistochemistry), and intertumoral 18F-FMISO accumulation levels and histological characteristics were determined. PET/CT was performed pre- and post-treatment with eribulin (0.3 mg/kg, i.p.). RESULTS The 18F-FMISO accumulation levels and percent pimonidazole-positive hypoxic area were significantly lower, whereas the number of microvessels was higher in the tumors treated with eribulin. The PET/CT confirmed that 18F-FMISO distribution in the tumor was decreased after the eribulin treatment. CONCLUSIONS Using 18F-FMISO, we demonstrated the elimination of the tumor hypoxic condition by eribulin treatment, concomitantly with the increase in microvessel density. These findings indicate that PET imaging using 18F-FMISO may provide the possibility to detect the early treatment response in clinical patients undergoing eribulin treatment.
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Affiliation(s)
- Songji Zhao
- Department of Tracer Kinetics and Bioanalysis, Graduate School of Medicine, Hokkaido University, Sapporo, Japan. .,Advanced Clinical Research Center, Fukushima Global Medical Science Center, Fukushima Medical University, 1 Hikariga-oka, Fukushima City, Fukushima, 960-1295, Japan.
| | - Wenwen Yu
- Department of Tracer Kinetics and Bioanalysis, Graduate School of Medicine, Hokkaido University, Sapporo, Japan
| | - Naoyuki Ukon
- Advanced Clinical Research Center, Fukushima Global Medical Science Center, Fukushima Medical University, 1 Hikariga-oka, Fukushima City, Fukushima, 960-1295, Japan.,Central Institute of Isotope Science, Hokkaido University, Sapporo, Japan
| | - Chengbo Tan
- Advanced Clinical Research Center, Fukushima Global Medical Science Center, Fukushima Medical University, 1 Hikariga-oka, Fukushima City, Fukushima, 960-1295, Japan
| | - Ken-Ichi Nishijima
- Central Institute of Isotope Science, Hokkaido University, Sapporo, Japan.,Department of Integrated Molecular Imaging, Graduate School of Medicine, Hokkaido University, Sapporo, Japan
| | - Yoichi Shimizu
- Faculty of Pharmaceutical Science, Hokkaido University, Sapporo, Japan
| | - Kei Higashikawa
- Central Institute of Isotope Science, Hokkaido University, Sapporo, Japan.,Department of Integrated Molecular Imaging, Graduate School of Medicine, Hokkaido University, Sapporo, Japan
| | - Tohru Shiga
- Department of Nuclear Medicine, Graduate School of Medicine, Hokkaido University, Sapporo, Japan
| | - Hiroko Yamashita
- Department of Breast Surgery, Graduate School of Medicine, Hokkaido University, Sapporo, Japan
| | - Nagara Tamaki
- Department of Nuclear Medicine, Graduate School of Medicine, Hokkaido University, Sapporo, Japan
| | - Yuji Kuge
- Central Institute of Isotope Science, Hokkaido University, Sapporo, Japan.,Department of Integrated Molecular Imaging, Graduate School of Medicine, Hokkaido University, Sapporo, Japan
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Shimizu Y, Motomura A, Takakura H, Tamaki N, Kuge Y, Ogawa M. Accumulation of hypoxia imaging probe “18F-FMISO” in macrophages depends on macrophage polarization in addition to hypoxic state. Ann Nucl Med 2019; 33:362-367. [DOI: 10.1007/s12149-019-01332-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Accepted: 01/09/2019] [Indexed: 10/27/2022]
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Emerging Functional Imaging Biomarkers of Tumour Responses to Radiotherapy. Cancers (Basel) 2019; 11:cancers11020131. [PMID: 30678055 PMCID: PMC6407112 DOI: 10.3390/cancers11020131] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Revised: 01/11/2019] [Accepted: 01/13/2019] [Indexed: 12/11/2022] Open
Abstract
Tumour responses to radiotherapy are currently primarily assessed by changes in size. Imaging permits non-invasive, whole-body assessment of tumour burden and guides treatment options for most tumours. However, in most tumours, changes in size are slow to manifest and can sometimes be difficult to interpret or misleading, potentially leading to prolonged durations of ineffective treatment and delays in changing therapy. Functional imaging techniques that monitor biological processes have the potential to detect tumour responses to treatment earlier and refine treatment options based on tumour biology rather than solely on size and staging. By considering the biological effects of radiotherapy, this review focusses on emerging functional imaging techniques with the potential to augment morphological imaging and serve as biomarkers of early response to radiotherapy.
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Shimizu Y. [Accumulation Mechanism of 2-Nitroimidazole-based Hypoxia Imaging Probes Revealed by Imaging Mass Spectrometry]. YAKUGAKU ZASSHI 2018; 138:1345-1352. [PMID: 30381642 DOI: 10.1248/yakushi.18-00146] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Hypoxia in tumor tissues plays a pivotal role in tumor progression and angiogenesis, and is associated with cancer therapeutic resistance. For the diagnosis of hypoxia, non-invasive imaging techniques, especially positron emission tomography (PET) with 2-nitroimidazole-based probes, are used, since 2-nitroimidazole-based probes are considered to undergo reductive metabolism on their 2-nitroimidazole moiety and become trapped in hypoxic cells. However, the detailed mechanism of their accumulation remains unclear because of the difficulty in estimating the metabolites by radioisotopic analysis. Imaging mass spectrometry (IMS) can distinguish the distribution patterns of the drug and its metabolites. To clarify the accumulation mechanism of 2-nitroimidazole-based probes in hypoxic cells, we evaluated [18F]fluoromisonidazole (FMISO), a 2-nitroimidazole-based PET probe, in combination with radioisotopic analysis and IMS. We found that the glutathione conjugate of reduced FMISO (amino-FMISO-GS) was the main FMISO metabolite, and was specifically distributed in the hypoxic regions of tumors. The same phenomenon was observed when we examined another 2-nitroimidazole-based probe, pimonidazole. The in vitro cellular uptake study revealed that FMISO accumulation in hypoxic cells depends on the cell type. In those cells exhibiting higher FMISO uptake, the reactive glutathione level and enzyme (glutathione S-transferase; GST) activity catalyzing the glutathione conjugation reaction was significantly higher, whereas the expression level of the efflux transporter (multidrug resistance-associated protein 1; MRP1) was significantly lower. Our study suggests that 2-nitroimidazole-based probes accumulate in hypoxic cells via glutathione conjugation following reductive metabolism, which depends not only on the glutathione conjugation capacity of the cells but also on hypoxic conditions.
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Farolfi A, Ghedini P, Fanti S. Highlights from 2017: impactful topics published in the Annals of Nuclear Medicine. Eur J Nucl Med Mol Imaging 2018; 46:217-223. [PMID: 30267115 DOI: 10.1007/s00259-018-4169-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Accepted: 09/13/2018] [Indexed: 01/08/2023]
Abstract
The aim of the review is to highlight articles published in 2017 in the Annals of Nuclear Medicine, an official peer-reviewed journal of the Japanese Society of Nuclear Medicine. Among all published manuscripts during the past year, we conducted a subjective selection of the most relevant topics. Fourteen fascinating articles are included in this review, ranging in topic from preclinical to clinical arenas.
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Affiliation(s)
- Andrea Farolfi
- Metropolitan Nuclear Medicine, S.Orsola-Malpighi Hospital, University of Bologna, Via Pietro Albertoni 15, 40138, Bologna, Italy.
| | - Pietro Ghedini
- Metropolitan Nuclear Medicine, S.Orsola-Malpighi Hospital, University of Bologna, Via Pietro Albertoni 15, 40138, Bologna, Italy
| | - Stefano Fanti
- Metropolitan Nuclear Medicine, S.Orsola-Malpighi Hospital, University of Bologna, Via Pietro Albertoni 15, 40138, Bologna, Italy
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