1
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Longo DL, Carella A, Corrado A, Pirotta E, Mohanta Z, Singh A, Stabinska J, Liu G, McMahon MT. A snapshot of the vast array of diamagnetic CEST MRI contrast agents. NMR IN BIOMEDICINE 2023; 36:e4715. [PMID: 35187749 PMCID: PMC9724179 DOI: 10.1002/nbm.4715] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 02/17/2022] [Accepted: 02/18/2022] [Indexed: 05/11/2023]
Abstract
Since the inception of CEST MRI in the 1990s, a number of compounds have been identified as suitable for generating contrast, including paramagnetic lanthanide complexes, hyperpolarized atom cages and, most interesting, diamagnetic compounds. In the past two decades, there has been a major emphasis in this field on the identification and application of diamagnetic compounds that have suitable biosafety profiles for usage in medical applications. Even in the past five years there has been a tremendous growth in their numbers, with more and more emphasis being placed on finding those that can be ultimately used for patient studies on clinical 3 T scanners. At this point, a number of endogenous compounds present in tissue have been identified, and also natural and synthetic organic compounds that can be administered to highlight pathology via CEST imaging. Here we will provide a very extensive snapshot of the types of diamagnetic compound that can generate CEST MRI contrast, together with guidance on their utility on typical preclinical and clinical scanners and a review of the applications that might benefit the most from this new technology.
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Affiliation(s)
- Dario Livio Longo
- Institute of Biostructures and Bioimaging (IBB), National Research Council of Italy (CNR), Turin, Italy
| | - Antonella Carella
- Institute of Biostructures and Bioimaging (IBB), National Research Council of Italy (CNR), Turin, Italy
| | - Alessia Corrado
- Institute of Biostructures and Bioimaging (IBB), National Research Council of Italy (CNR), Turin, Italy
| | - Elisa Pirotta
- Institute of Biostructures and Bioimaging (IBB), National Research Council of Italy (CNR), Turin, Italy
| | - Zinia Mohanta
- F.M. Kirby Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, USA
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Aruna Singh
- F.M. Kirby Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, USA
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Julia Stabinska
- F.M. Kirby Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, USA
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Guanshu Liu
- F.M. Kirby Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, USA
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Michael T. McMahon
- F.M. Kirby Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, USA
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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2
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Lado-Touriño I, Cerpa-Naranjo A. Coarse-Grained Molecular Dynamics of pH-Sensitive Lipids. Int J Mol Sci 2023; 24:ijms24054632. [PMID: 36902063 PMCID: PMC10003205 DOI: 10.3390/ijms24054632] [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] [Received: 01/20/2023] [Revised: 02/20/2023] [Accepted: 02/25/2023] [Indexed: 03/06/2023] Open
Abstract
pH-sensitive lipids represent a class of lipids that can be protonated and destabilized in acidic environments, as they become positively charged in response to low-pH conditions. They can be incorporated into lipidic nanoparticles such as liposomes, which are able to change their properties and allow specific drug delivery at the acidic conditions encountered in some pathological microenvironments. In this work, we used coarse-grained molecular-dynamic simulations to study the stability of neutral and charged lipid bilayers containing POPC (1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine) and various kinds of ISUCA ((F)2-(imidazol-1-yl)succinic acid)-derived lipids, which can act as pH-sensitive molecules. In order to explore such systems, we used a MARTINI-derived forcefield, previously parameterized using all-atom simulation results. We calculated the average area per lipid, the second-rank order parameter and the lipid diffusion coefficient of both lipid bilayers made of pure components and mixtures of lipids in different proportions, under neutral or acidic conditions. The results show that the use of ISUCA-derived lipids disturbs the lipid bilayer structure, with the effect being particularly marked under acidic conditions. Although more-in depth studies on these systems must be carried out, these initial results are encouraging and the lipids designed in this research could be a good basis for developing new pH-sensitive liposomes.
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3
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Caro C, Pourmadadi M, Eshaghi MM, Rahmani E, Shojaei S, Paiva-Santos AC, Rahdar A, Behzadmehr R, García-Martín ML, Díez-Pascual AM. Nanomaterials loaded with Quercetin as an advanced tool for cancer treatment. J Drug Deliv Sci Technol 2022. [DOI: 10.1016/j.jddst.2022.103938] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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4
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Moisoiu V, Iancu SD, Stefancu A, Moisoiu T, Pardini B, Dragomir MP, Crisan N, Avram L, Crisan D, Andras I, Fodor D, Leopold LF, Socaciu C, Bálint Z, Tomuleasa C, Elec F, Leopold N. SERS liquid biopsy: An emerging tool for medical diagnosis. Colloids Surf B Biointerfaces 2021; 208:112064. [PMID: 34517219 DOI: 10.1016/j.colsurfb.2021.112064] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 08/09/2021] [Accepted: 08/20/2021] [Indexed: 02/02/2023]
Abstract
Surface-enhanced Raman scattering (SERS) is emerging as a novel strategy for biofluid analysis. In this review, we delineate four experimental SERS protocols that are frequently used for the profiling of biofluids: 1) liquid SERS for the detection of purine metabolites; 2) iodide-modified liquid SERS for the detection of proteins; 3) dried SERS for the detection of both purine metabolites and proteins; 4) resonant Raman for the detection of carotenoids. To explain the selectivity of each experimental SERS protocol, we introduce a heuristic model for the chemisorption of analytes mediated by adsorbed ions (adions) onto the SERS substrate. Next, we show that the promising results of SERS liquid biopsy stem from the fact that the concentration levels of purine metabolites, proteins and carotenoids are informative of the cellular turnover rate, inflammation, and oxidative stress, respectively. These processes are perturbed in virtually every disease, from cancer to autoimmune maladies. Finally, we review recent SERS liquid biopsy studies and discuss future steps that are required for translating SERS in the clinical setting.
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Affiliation(s)
- Vlad Moisoiu
- Faculty of Physics, Babeș-Bolyai University, 400084, Cluj-Napoca, Romania
| | - Stefania D Iancu
- Faculty of Physics, Babeș-Bolyai University, 400084, Cluj-Napoca, Romania
| | - Andrei Stefancu
- Faculty of Physics, Babeș-Bolyai University, 400084, Cluj-Napoca, Romania
| | - Tudor Moisoiu
- Clinical Institute of Urology and Renal Transplant, 400006, Cluj-Napoca, Romania; Biomed Data Analytics SRL, 400696, Cluj-Napoca, Romania; Department of Urology, Faculty of Medicine, Iuliu Hatieganu University of Medicine and Pharmacy, 400012, Cluj-Napoca, Romania
| | - Barbara Pardini
- Candiolo Cancer Institute, FPO-IRCCS, 10060, Candiolo, Italy; Italian Institute of Genomic Medicine (IIGM), 10060, Candiolo, Italy
| | - Mihnea P Dragomir
- Institute of Pathology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 10117, Berlin, Germany
| | - Nicolae Crisan
- Department of Urology, Faculty of Medicine, Iuliu Hatieganu University of Medicine and Pharmacy, 400012, Cluj-Napoca, Romania; Clinical Municipal Hospital, 400139, Cluj-Napoca, Romania
| | - Lucretia Avram
- Clinical Municipal Hospital, 400139, Cluj-Napoca, Romania; Department of Geriatrics, Faculty of Medicine, Iuliu Hatieganu University of Medicine and Pharmacy, 400012, Cluj-Napoca, Romania
| | - Dana Crisan
- Clinical Municipal Hospital, 400139, Cluj-Napoca, Romania; 5th Internal Medicine Department, Faculty of Medicine, Iuliu Hatieganu University of Medicine and Pharmacy, 400012, Cluj-Napoca, Romania
| | - Iulia Andras
- Department of Urology, Faculty of Medicine, Iuliu Hatieganu University of Medicine and Pharmacy, 400012, Cluj-Napoca, Romania; Clinical Municipal Hospital, 400139, Cluj-Napoca, Romania
| | - Daniela Fodor
- 2nd Internal Medicine Department, Iuliu Hatieganu University of Medicine and Pharmacy, 400006, Cluj-Napoca, Romania
| | - Loredana F Leopold
- Faculty of Food Science and Technology, University of Agricultural Sciences and Veterinary Medicine, 400372, Cluj-Napoca, Romania
| | - Carmen Socaciu
- Faculty of Food Science and Technology, University of Agricultural Sciences and Veterinary Medicine, 400372, Cluj-Napoca, Romania; BIODIATECH Research Centre for Applied Biotechnology, SC Proplanta, 400478, Cluj-Napoca, Romania
| | - Zoltán Bálint
- Faculty of Physics, Babeș-Bolyai University, 400084, Cluj-Napoca, Romania
| | - Ciprian Tomuleasa
- Department of Hematology, Iuliu Hatieganu University of Medicine and Pharmacy, 400124, Cluj-Napoca, Romania; Department of Hematology, Ion Chiricuta Clinical Cancer Center, 400124, Cluj-Napoca, Romania; Medfuture Research Center for Advanced Medicine, Iuliu Hatieganu University of Medicine and Pharmacy, 400349, Cluj-Napoca, Romania
| | - Florin Elec
- Clinical Institute of Urology and Renal Transplant, 400006, Cluj-Napoca, Romania; Department of Urology, Faculty of Medicine, Iuliu Hatieganu University of Medicine and Pharmacy, 400012, Cluj-Napoca, Romania.
| | - Nicolae Leopold
- Faculty of Physics, Babeș-Bolyai University, 400084, Cluj-Napoca, Romania; Biomed Data Analytics SRL, 400696, Cluj-Napoca, Romania.
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5
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In situ potentiometric SECM monitoring of the extracellular pH changes under electrical stimulation using a dual-microelectrode tip. J Electroanal Chem (Lausanne) 2021. [DOI: 10.1016/j.jelechem.2021.115169] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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6
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Kim H, Krishnamurthy LC, Sun PZ. Brain pH Imaging and its Applications. Neuroscience 2021; 474:51-62. [PMID: 33493621 DOI: 10.1016/j.neuroscience.2021.01.026] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 01/12/2021] [Accepted: 01/13/2021] [Indexed: 12/14/2022]
Abstract
Acid-base homeostasis and pH regulation are critical for normal tissue metabolism and physiology, and brain tissue pH alters in many diseased states. Several noninvasive tissue pH Magnetic Resonance (MR) techniques have been developed over the past few decades to shed light on pH change during tissue function and dysfunction. Nevertheless, there are still challenges for mapping brain pH noninvasively at high spatiotemporal resolution. To address this unmet biomedical need, chemical exchange saturation transfer (CEST) MR techniques have been developed as a sensitive means for non-invasive pH mapping. This article briefly reviews the basic principles of different pH measurement techniques with a focus on CEST imaging of pH. Emerging pH imaging applications in the tumor are provided as examples throughout the narrative, and CEST pH imaging in acute stroke is discussed in the final section.
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Affiliation(s)
- Hahnsung Kim
- Yerkes Imaging Center, Yerkes National Primate Research Center, Emory University, Atlanta, GA, United States; Department of Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, GA, United States
| | - Lisa C Krishnamurthy
- Center for Visual and Neurocognitive Rehabilitation, Atlanta VA, Decatur, GA, United States; Department of Physics & Astronomy, Georgia State University, Atlanta, GA, United States
| | - Phillip Zhe Sun
- Yerkes Imaging Center, Yerkes National Primate Research Center, Emory University, Atlanta, GA, United States; Department of Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, GA, United States.
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7
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Lee SH, Griffiths JR. How and Why Are Cancers Acidic? Carbonic Anhydrase IX and the Homeostatic Control of Tumour Extracellular pH. Cancers (Basel) 2020; 12:cancers12061616. [PMID: 32570870 PMCID: PMC7352839 DOI: 10.3390/cancers12061616] [Citation(s) in RCA: 60] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2020] [Revised: 06/13/2020] [Accepted: 06/15/2020] [Indexed: 12/11/2022] Open
Abstract
The acidic tumour microenvironment is now recognized as a tumour phenotype that drives cancer somatic evolution and disease progression, causing cancer cells to become more invasive and to metastasise. This property of solid tumours reflects a complex interplay between cellular carbon metabolism and acid removal that is mediated by cell membrane carbonic anhydrases and various transport proteins, interstitial fluid buffering, and abnormal tumour-associated vessels. In the past two decades, a convergence of advances in the experimental and mathematical modelling of human cancers, as well as non-invasive pH-imaging techniques, has yielded new insights into the physiological mechanisms that govern tumour extracellular pH (pHe). In this review, we examine the mechanisms by which solid tumours maintain a low pHe, with a focus on carbonic anhydrase IX (CAIX), a cancer-associated cell surface enzyme. We also review the accumulating evidence that suggest a role for CAIX as a biological pH-stat by which solid tumours stabilize their pHe. Finally, we highlight the prospects for the clinical translation of CAIX-targeted therapies in oncology.
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Affiliation(s)
- Shen-Han Lee
- Department of Otorhinolaryngology, Hospital Sultanah Bahiyah, Jalan Langgar, Alor Setar 05460, Kedah, Malaysia
- Correspondence:
| | - John R. Griffiths
- Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Robinson Way, Cambridge CB2 0RE, UK;
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8
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Real-time monitoring of extracellular pH using a pH-potentiometric sensing SECM dual-microelectrode. Anal Bioanal Chem 2020; 412:3737-3743. [DOI: 10.1007/s00216-020-02625-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2020] [Revised: 03/25/2020] [Accepted: 03/27/2020] [Indexed: 02/07/2023]
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9
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Anemone A, Consolino L, Arena F, Capozza M, Longo DL. Imaging tumor acidosis: a survey of the available techniques for mapping in vivo tumor pH. Cancer Metastasis Rev 2020; 38:25-49. [PMID: 30762162 PMCID: PMC6647493 DOI: 10.1007/s10555-019-09782-9] [Citation(s) in RCA: 98] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Cancer cells are characterized by a metabolic shift in cellular energy production, orchestrated by the transcription factor HIF-1α, from mitochondrial oxidative phosphorylation to increased glycolysis, regardless of oxygen availability (Warburg effect). The constitutive upregulation of glycolysis leads to an overproduction of acidic metabolic products, resulting in enhanced acidification of the extracellular pH (pHe ~ 6.5), which is a salient feature of the tumor microenvironment. Despite the importance of pH and tumor acidosis, there is currently no established clinical tool available to image the spatial distribution of tumor pHe. The purpose of this review is to describe various imaging modalities for measuring intracellular and extracellular tumor pH. For each technique, we will discuss main advantages and limitations, pH accuracy and sensitivity of the applied pH-responsive probes and potential translatability to the clinic. Particular attention is devoted to methods that can provide pH measurements at high spatial resolution useful to address the task of tumor heterogeneity and to studies that explored tumor pH imaging for assessing treatment response to anticancer therapies.
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Affiliation(s)
- Annasofia Anemone
- Molecular Imaging Center, Department of Molecular Biotechnology and Health Sciences, University of Turin, Via Nizza 52, Turin, Italy
| | - Lorena Consolino
- Molecular Imaging Center, Department of Molecular Biotechnology and Health Sciences, University of Turin, Via Nizza 52, Turin, Italy
| | - Francesca Arena
- Institute of Biostructures and Bioimaging (IBB), Italian National Research Council (CNR), Via Nizza 52, Turin, Italy.,Center for Preclinical Imaging, Department of Molecular Biotechnology and Health Sciences, University of Turin, Via Ribes 5, Colleretto Giacosa, Italy
| | - Martina Capozza
- Center for Preclinical Imaging, Department of Molecular Biotechnology and Health Sciences, University of Turin, Via Ribes 5, Colleretto Giacosa, Italy
| | - Dario Livio Longo
- Molecular Imaging Center, Department of Molecular Biotechnology and Health Sciences, University of Turin, Via Nizza 52, Turin, Italy. .,Institute of Biostructures and Bioimaging (IBB), Italian National Research Council (CNR), Via Nizza 52, Turin, Italy.
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10
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Lutz NW, Bernard M. Multiparametric statistical quantification of pH heterogeneity by 1 H MRS and MRSI of extracellular pH markers: Proof of principle. NMR IN BIOMEDICINE 2019; 32:e4134. [PMID: 31313874 DOI: 10.1002/nbm.4134] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Revised: 05/14/2019] [Accepted: 06/02/2019] [Indexed: 06/10/2023]
Abstract
Acid production and transport in numerous biological tissues and medical conditions are active areas of research. Heterogeneity of pH within a given homogeneous-appearing tissue volume has been reported, but none of the conventional methods currently available for measuring tissue pH provides quantitative parameters describing the frequency of occurrence of pH values within such a volume. We have previously presented a multiparametric noninvasive in vivo approach, providing at least 10 different statistical descriptors of pH heterogeneity based on a novel type of line shape analysis developed for pH-sensitive 31 P MRS resonances. However, this method suffers from lack of sensitivity, thus making rapid and spatially resolved measurements difficult. We present here the proof of principle of a new, more sensitive approach to statistical characterization of extracellular pH heterogeneity based on 1 H MRS, with the potential of being combined with spatial resolution. We experimentally study a range of test solutions of a reporter molecule that has previously been shown to possess a 1 H MRS resonance whose chemical shift varies with pH, including when injected intravenously into experimental animals (imidazole ethoxycarbonylpropionic acid, [IEPA]). Statistical pH heterogeneity descriptors are determined for phantoms mimicking tissue pH heterogeneity. To this end, the pH-sensitive 1 H MRS resonance is transformed into a pH curve. Subsequently, the digital points of this pH profile are used to build a histogram using dedicated algorithms. The following descriptors are computed from this histogram: weighted mean pH and median pH, pH standard deviation, pH range, pH mode(s), pH kurtosis, pH skewness and pH entropy. Our new method is also validated by analyzing previously published in vivo MRSI spectra. The proof of principle provided in this work should form the basis of further in vivo studies in physiology and medicine, eg in cancer research, but also in other fields such as kidney and muscle research.
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11
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Korenchan DE, Bok R, Sriram R, Liu K, Santos RD, Qin H, Lobach I, Korn N, Wilson DM, Kurhanewicz J, Flavell RR. Hyperpolarized in vivo pH imaging reveals grade-dependent acidification in prostate cancer. Oncotarget 2019; 10:6096-6110. [PMID: 31692908 PMCID: PMC6817439 DOI: 10.18632/oncotarget.27225] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Accepted: 09/10/2019] [Indexed: 01/29/2023] Open
Abstract
There is an unmet clinical need for new and robust imaging biomarkers to distinguish indolent from aggressive prostate cancer. Hallmarks of aggressive tumors such as a decrease in extracellular pH (pHe) can potentially be used to identify aggressive phenotypes. In this study, we employ an optimized, high signal-to-noise ratio hyperpolarized (HP) 13C pHe imaging method to discriminate between indolent and aggressive disease in a murine model of prostate cancer. Transgenic adenocarcinoma of the mouse prostate (TRAMP) mice underwent a multiparametric MR imaging exam, including HP [13C] bicarbonate MRI for pHe, with 1H apparent diffusion coefficient (ADC) mapping and HP [1-13C] pyruvate MRI to study lactate metabolism. Tumor tissue was excised for histological staining and qRT-PCR to quantify mRNA expression for relevant glycolytic enzymes and transporters. We observed good separation in pHe between low- and high-grade tumor regions, with high-grade tumors demonstrating a lower pHe. The pHe also correlated strongly with monocarboxylate transporter Mct4 gene expression across all tumors, suggesting that lactate export via MCT4 is associated with acidification in this model. Our results implicate extracellular acidification as an indicator of indolent-to-aggressive transition in prostate cancer and suggest feasibility of HP pHe imaging to detect high-grade, clinically significant disease in men as part of a multiparametric MRI examination.
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Affiliation(s)
- David E Korenchan
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, CA, USA
| | - Robert Bok
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, CA, USA
| | - Renuka Sriram
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, CA, USA
| | - Kristina Liu
- Department of Physical Chemistry, Technical University of Munich, Munich, Germany
| | - Romelyn Delos Santos
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, CA, USA
| | - Hecong Qin
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, CA, USA
| | - Iryna Lobach
- Department of Epidemiology and Biostatistics, University of California, San Francisco, CA, USA
| | - Natalie Korn
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, CA, USA
| | - David M Wilson
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, CA, USA
| | - John Kurhanewicz
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, CA, USA.,Department of Pharmaceutical Chemistry, University of California, San Francisco, CA, USA.,Department of Urology, University of California, San Francisco, CA, USA
| | - Robert R Flavell
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, CA, USA.,Department of Pharmaceutical Chemistry, University of California, San Francisco, CA, USA
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12
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Spatiotemporal pH Heterogeneity as a Promoter of Cancer Progression and Therapeutic Resistance. Cancers (Basel) 2019; 11:cancers11071026. [PMID: 31330859 PMCID: PMC6678451 DOI: 10.3390/cancers11071026] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Revised: 07/17/2019] [Accepted: 07/18/2019] [Indexed: 12/15/2022] Open
Abstract
Dysregulation of pH in solid tumors is a hallmark of cancer. In recent years, the role of altered pH heterogeneity in space, between benign and aggressive tissues, between individual cancer cells, and between subcellular compartments, has been steadily elucidated. Changes in temporal pH-related processes on both fast and slow time scales, including altered kinetics of bicarbonate-CO2 exchange and its effects on pH buffering and gradual, progressive changes driven by changes in metabolism, are further implicated in phenotypic changes observed in cancers. These discoveries have been driven by advances in imaging technologies. This review provides an overview of intra- and extracellular pH alterations in time and space reflected in cancer cells, as well as the available technology to study pH spatiotemporal heterogeneity.
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13
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Komarov DA, Ichikawa Y, Yamamoto K, Stewart NJ, Matsumoto S, Yasui H, Kirilyuk IA, Khramtsov VV, Inanami O, Hirata H. In Vivo Extracellular pH Mapping of Tumors Using Electron Paramagnetic Resonance. Anal Chem 2018; 90:13938-13945. [PMID: 30372035 DOI: 10.1021/acs.analchem.8b03328] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
An electron paramagnetic resonance (EPR)-based method for noninvasive three-dimensional extracellular pH mapping was developed using a pH-sensitive nitroxyl radical as an exogenous paramagnetic probe. Fast projection scanning with a constant magnetic field sweep enabled the acquisition of four-dimensional (3D spatial +1D spectral) EPR images within 7.5 min. Three-dimensional maps of pH were reconstructed by processing the pH-dependent spectral information on the images. To demonstrate the proposed method of pH mapping, the progress of extracellular acidosis in tumor-bearing mouse legs was studied. Furthermore, extracellular pH mapping was used to visualize the spatial distribution of acidification in different tumor xenograft mouse models of human-derived pancreatic ductal adenocarcinoma cells. The proposed EPR-based pH mapping method enabled quantitative visualization of regional changes in extracellular pH associated with altered tumor metabolism.
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Affiliation(s)
- Denis A Komarov
- Division of Bioengineering and Bioinformatics, Graduate School of Information Science and Technology , Hokkaido University , North 14, West 9 , Kita-ku, Sapporo , 060-0814 , Japan
| | - Yuki Ichikawa
- Division of Bioengineering and Bioinformatics, Graduate School of Information Science and Technology , Hokkaido University , North 14, West 9 , Kita-ku, Sapporo , 060-0814 , Japan
| | - Kumiko Yamamoto
- Laboratory of Radiation Biology, Graduate School of Veterinary Medicine , Hokkaido University , North 18, West 9 , Kita-ku, Sapporo , 060-0818 , Japan
| | - Neil J Stewart
- Division of Bioengineering and Bioinformatics, Graduate School of Information Science and Technology , Hokkaido University , North 14, West 9 , Kita-ku, Sapporo , 060-0814 , Japan
| | - Shingo Matsumoto
- Division of Bioengineering and Bioinformatics, Graduate School of Information Science and Technology , Hokkaido University , North 14, West 9 , Kita-ku, Sapporo , 060-0814 , Japan
| | - Hironobu Yasui
- Central Institute of Isotope Science , Hokkaido University , North 15, West 7 , Kita-ku,Sapporo , 060-0815 , Japan
| | - Igor A Kirilyuk
- N. N. Vorozhtsov Novosibirsk Institute of Organic Chemistry , 9, Ac. Lavrentieva Ave. , Novosibirsk , 630090 , Russia
| | - Valery V Khramtsov
- Department of Biochemistry and In Vivo Multifunctional Magnetic Resonance Center , West Virginia University, Robert C. Byrd Health Sciences Center , 1 Medical Center Drive , Morgantown , West Virginia 26506 , United States
| | - Osamu Inanami
- Laboratory of Radiation Biology, Graduate School of Veterinary Medicine , Hokkaido University , North 18, West 9 , Kita-ku, Sapporo , 060-0818 , Japan
| | - Hiroshi Hirata
- Division of Bioengineering and Bioinformatics, Graduate School of Information Science and Technology , Hokkaido University , North 14, West 9 , Kita-ku, Sapporo , 060-0814 , Japan
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14
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Lee SH, McIntyre D, Honess D, Hulikova A, Pacheco-Torres J, Cerdán S, Swietach P, Harris AL, Griffiths JR. Carbonic anhydrase IX is a pH-stat that sets an acidic tumour extracellular pH in vivo. Br J Cancer 2018; 119:622-630. [PMID: 30206370 PMCID: PMC6162214 DOI: 10.1038/s41416-018-0216-5] [Citation(s) in RCA: 71] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Revised: 06/26/2018] [Accepted: 07/12/2018] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND Tumour carbonic anhydrase IX (CAIX), a hypoxia-inducible tumour-associated cell surface enzyme, is thought to acidify the tumour microenvironment by hydrating CO2 to form protons and bicarbonate, but there is no definitive evidence for this in solid tumours in vivo. METHODS We used 1H magnetic resonance spectroscopic imaging (MRSI) of the extracellular pH probe imidazolyl succinic acid (ISUCA) to measure and spatially map extracellular pH in HCT116 tumours transfected to express CAIX and empty vector controls in SCID mice. We also measured intracellular pH in situ with 31P MRS and measured lactate in freeze-clamped tumours. RESULTS CAIX-expressing tumours had 0.15 pH-unit lower median extracellular pH than control tumours (pH 6.71 tumour vs pH 6.86 control, P = 0.01). Importantly, CAIX expression imposed an upper limit for tumour extracellular pH at 6.93. Despite the increased lactate concentration in CAIX-expressing tumours, 31P MRS showed no difference in intracellular pH, suggesting that CAIX acidifies only the tumour extracellular space. CONCLUSIONS CAIX acidifies the tumour microenvironment, and also provides an extracellular pH control mechanism. We propose that CAIX thus acts as an extracellular pH-stat, maintaining an acidic tumour extracellular pH that is tolerated by cancer cells and favours invasion and metastasis.
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Affiliation(s)
- Shen-Han Lee
- Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Robinson Way, Cambridge, CB2 0RE, UK
- Singapore Health Services (SingHealth), Department of General Surgery, Singapore General Hospital, Academia, College Road, Singapore, 169856, Singapore
| | - Dominick McIntyre
- Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Robinson Way, Cambridge, CB2 0RE, UK
| | - Davina Honess
- Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Robinson Way, Cambridge, CB2 0RE, UK
| | - Alzbeta Hulikova
- Department of Physiology, Anatomy & Genetics, University of Oxford, Parks Road, Oxford, OX1 3PT, UK
| | - Jesús Pacheco-Torres
- Division of Cancer Imaging Research, The Johns Hopkins University School of Medicine, 720 Rutland Avenue, Traylor 211, Baltimore, MD, 21205, USA
| | - Sebastián Cerdán
- Instituto de Investigaciones Biomédicas "Alberto Sols", c/ Arturo Duperier 4, Madrid, 28029, Spain
| | - Pawel Swietach
- Department of Physiology, Anatomy & Genetics, University of Oxford, Parks Road, Oxford, OX1 3PT, UK
| | - Adrian L Harris
- Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, OX3 9DS, UK
| | - John R Griffiths
- Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Robinson Way, Cambridge, CB2 0RE, UK.
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15
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Hyperpolarized Amino Acid Derivatives as Multivalent Magnetic Resonance pH Sensor Molecules. SENSORS 2018; 18:s18020600. [PMID: 29462891 PMCID: PMC5856118 DOI: 10.3390/s18020600] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Revised: 02/07/2018] [Accepted: 02/08/2018] [Indexed: 11/17/2022]
Abstract
pH is a tightly regulated physiological parameter that is often altered in diseased states like cancer. The development of biosensors that can be used to non-invasively image pH with hyperpolarized (HP) magnetic resonance spectroscopic imaging has therefore recently gained tremendous interest. However, most of the known HP-sensors have only individually and not comprehensively been analyzed for their biocompatibility, their pH sensitivity under physiological conditions, and the effects of chemical derivatization on their logarithmic acid dissociation constant (pKa). Proteinogenic amino acids are biocompatible, can be hyperpolarized and have at least two pH sensitive moieties. However, they do not exhibit a pH sensitivity in the physiologically relevant pH range. Here, we developed a systematic approach to tailor the pKa of molecules using modifications of carbon chain length and derivatization rendering these molecules interesting for pH biosensing. Notably, we identified several derivatives such as [1-13C]serine amide and [1-13C]-2,3-diaminopropionic acid as novel pH sensors. They bear several spin-1/2 nuclei (13C, 15N, 31P) with high sensitivity up to 4.8 ppm/pH and we show that 13C spins can be hyperpolarized with dissolution dynamic polarization (DNP). Our findings elucidate the molecular mechanisms of chemical shift pH sensors that might help to design tailored probes for specific pH in vivo imaging applications.
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16
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Zhang C, Liu Z, Zheng Y, Geng Y, Han C, Shi Y, Sun H, Zhang C, Chen Y, Zhang L, Guo Q, Yang L, Zhou X, Kong L. Glycyrrhetinic Acid Functionalized Graphene Oxide for Mitochondria Targeting and Cancer Treatment In Vivo. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2018; 14:1703306. [PMID: 29205852 DOI: 10.1002/smll.201703306] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2017] [Indexed: 06/07/2023]
Abstract
Mitochondria-mediated apoptosis (MMA) is a preferential option for cancer therapy due to the presence of cell-suicide factors in mitochondria, however, low permeability of mitochondria is a bottleneck for targeting drug delivery. In this paper, glycyrrhetinic acid (GA), a natural product from Glycyrrhiza glabra, is found to be a novel mitochondria targeting ligand, which can improve mitochondrial permeability and enhance the drug uptake of mitochondria. GA-functionalized graphene oxide (GO) is prepared and used as an effective carrier for targeted delivery of doxorubicin into mitochondria. The detailed in vitro and in vivo mechanism study shows that GA-functionalized GO causes a decrease in mitochondrial membrane potential and activates the MMA pathway. The GA-functionalized drug delivery system demonstrates highly improved apoptosis induction ability and anticancer efficacy compared to the non-GA-functionalized nanocarrier delivery system. The GA-functionalized nanocarrier also shows low toxicity, suggesting that it can be a useful tool for drug delivery.
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Affiliation(s)
- Chao Zhang
- State Key Laboratory of Natural Medicines, Department of Natural Medicinal Chemistry, China Pharmaceutical University, Nanjing, Jiangsu, 210009, China
| | - Zunfeng Liu
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Functional Polymer Materials, Ministry of Education, College of Pharmacy, Nankai University, Tianjin, 300071, China
| | - Ying Zheng
- Department of Science, China Pharmaceutical University, Nanjing, 211198, China
| | - Yadi Geng
- State Key Laboratory of Natural Medicines, Department of Natural Medicinal Chemistry, China Pharmaceutical University, Nanjing, Jiangsu, 210009, China
| | - Chao Han
- State Key Laboratory of Natural Medicines, Department of Natural Medicinal Chemistry, China Pharmaceutical University, Nanjing, Jiangsu, 210009, China
| | - Yamin Shi
- State Key Laboratory of Natural Medicines, Department of Natural Medicinal Chemistry, China Pharmaceutical University, Nanjing, Jiangsu, 210009, China
| | - Hongbin Sun
- State Key Laboratory of Natural Medicines, Department of Natural Medicinal Chemistry, China Pharmaceutical University, Nanjing, Jiangsu, 210009, China
| | - Can Zhang
- State Key Laboratory of Natural Medicines, Department of Natural Medicinal Chemistry, China Pharmaceutical University, Nanjing, Jiangsu, 210009, China
| | - Yijun Chen
- State Key Laboratory of Natural Medicines, Department of Natural Medicinal Chemistry, China Pharmaceutical University, Nanjing, Jiangsu, 210009, China
| | - Luyong Zhang
- State Key Laboratory of Natural Medicines, Department of Natural Medicinal Chemistry, China Pharmaceutical University, Nanjing, Jiangsu, 210009, China
| | - Qinglong Guo
- State Key Laboratory of Natural Medicines, Department of Natural Medicinal Chemistry, China Pharmaceutical University, Nanjing, Jiangsu, 210009, China
| | - Lei Yang
- State Key Laboratory of Natural Medicines, Department of Natural Medicinal Chemistry, China Pharmaceutical University, Nanjing, Jiangsu, 210009, China
| | - Xiang Zhou
- Department of Science, China Pharmaceutical University, Nanjing, 211198, China
| | - Lingyi Kong
- State Key Laboratory of Natural Medicines, Department of Natural Medicinal Chemistry, China Pharmaceutical University, Nanjing, Jiangsu, 210009, China
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17
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Abstract
Clinical imaging modalities have reached a prominent role in medical diagnosis and patient management in the last decades. Different image methodologies as Positron Emission Tomography, Single Photon Emission Tomography, X-Rays, or Magnetic Resonance Imaging are in continuous evolution to satisfy the increasing demands of current medical diagnosis. Progress in these methodologies has been favored by the parallel development of increasingly more powerful contrast agents. These are molecules that enhance the intrinsic contrast of the images in the tissues where they accumulate, revealing noninvasively the presence of characteristic molecular targets or differential physiopathological microenvironments. The contrast agent field is currently moving to improve the performance of these molecules by incorporating the advantages that modern nanotechnology offers. These include, mainly, the possibilities to combine imaging and therapeutic capabilities over the same theranostic platform or improve the targeting efficiency in vivo by molecular engineering of the nanostructures. In this review, we provide an introduction to multimodal imaging methods in biomedicine, the sub-nanometric imaging agents previously used and the development of advanced multimodal and theranostic imaging agents based in nanotechnology. We conclude providing some illustrative examples from our own laboratories, including recent progress in theranostic formulations of magnetoliposomes containing ω-3 poly-unsaturated fatty acids to treat inflammatory diseases, or the use of stealth liposomes engineered with a pH-sensitive nanovalve to release their cargo specifically in the acidic extracellular pH microenvironment of tumors.
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18
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Hundshammer C, Düwel S, Schilling F. Imaging of Extracellular pH Using Hyperpolarized Molecules. Isr J Chem 2017. [DOI: 10.1002/ijch.201700017] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Christian Hundshammer
- Department of Nuclear Medicine, Klinikum rechts der Isar; Technical University of Munich; Ismaninger Str. 22 81675 München Germany
- Department of Chemistry; Technical University of Munich; Lichtenbergstr. 2 85748 Garching Germany
| | - Stephan Düwel
- Department of Nuclear Medicine, Klinikum rechts der Isar; Technical University of Munich; Ismaninger Str. 22 81675 München Germany
- Department of Chemistry; Technical University of Munich; Lichtenbergstr. 2 85748 Garching Germany
- Institute of Medical Engineering; Technical University of Munich; Boltzmannstr. 11 85748 Garching Germany
| | - Franz Schilling
- Department of Nuclear Medicine, Klinikum rechts der Isar; Technical University of Munich; Ismaninger Str. 22 81675 München Germany
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19
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Sikkandhar MG, Nedumaran AM, Ravichandar R, Singh S, Santhakumar I, Goh ZC, Mishra S, Archunan G, Gulyás B, Padmanabhan P. Theranostic Probes for Targeting Tumor Microenvironment: An Overview. Int J Mol Sci 2017; 18:E1036. [PMID: 28492519 PMCID: PMC5454948 DOI: 10.3390/ijms18051036] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2017] [Revised: 05/06/2017] [Accepted: 05/08/2017] [Indexed: 01/07/2023] Open
Abstract
Long gone is the time when tumors were thought to be insular masses of cells, residing independently at specific sites in an organ. Now, researchers gradually realize that tumors interact with the extracellular matrix (ECM), blood vessels, connective tissues, and immune cells in their environment, which is now known as the tumor microenvironment (TME). It has been found that the interactions between tumors and their surrounds promote tumor growth, invasion, and metastasis. The dynamics and diversity of TME cause the tumors to be heterogeneous and thus pose a challenge for cancer diagnosis, drug design, and therapy. As TME is significant in enhancing tumor progression, it is vital to identify the different components in the TME such as tumor vasculature, ECM, stromal cells, and the lymphatic system. This review explores how these significant factors in the TME, supply tumors with the required growth factors and signaling molecules to proliferate, invade, and metastasize. We also examine the development of TME-targeted nanotheranostics over the recent years for cancer therapy, diagnosis, and anticancer drug delivery systems. This review further discusses the limitations and future perspective of nanoparticle based theranostics when used in combination with current imaging modalities like Optical Imaging, Magnetic Resonance Imaging (MRI) and Nuclear Imaging (Positron Emission Tomography (PET) and Single Photon Emission Computer Tomography (SPECT)).
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Affiliation(s)
- Musafar Gani Sikkandhar
- Lee Kong Chian School of Medicine, Nanyang Technological University, 59 Nanyang Drive, Singapore 636921, Singapore.
| | - Anu Maashaa Nedumaran
- Lee Kong Chian School of Medicine, Nanyang Technological University, 59 Nanyang Drive, Singapore 636921, Singapore.
| | - Roopa Ravichandar
- Lee Kong Chian School of Medicine, Nanyang Technological University, 59 Nanyang Drive, Singapore 636921, Singapore.
| | - Satnam Singh
- Lee Kong Chian School of Medicine, Nanyang Technological University, 59 Nanyang Drive, Singapore 636921, Singapore.
| | - Induja Santhakumar
- Lee Kong Chian School of Medicine, Nanyang Technological University, 59 Nanyang Drive, Singapore 636921, Singapore.
| | - Zheng Cong Goh
- Lee Kong Chian School of Medicine, Nanyang Technological University, 59 Nanyang Drive, Singapore 636921, Singapore.
| | - Sachin Mishra
- Lee Kong Chian School of Medicine, Nanyang Technological University, 59 Nanyang Drive, Singapore 636921, Singapore.
| | - Govindaraju Archunan
- Centre for Pheromone Technology, Department of Animal Science, Bharathidasan University, Tiruchirappalli 620024, India.
| | - Balázs Gulyás
- Lee Kong Chian School of Medicine, Nanyang Technological University, 59 Nanyang Drive, Singapore 636921, Singapore.
| | - Parasuraman Padmanabhan
- Lee Kong Chian School of Medicine, Nanyang Technological University, 59 Nanyang Drive, Singapore 636921, Singapore.
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20
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Ramamonjisoa N, Ackerstaff E. Characterization of the Tumor Microenvironment and Tumor-Stroma Interaction by Non-invasive Preclinical Imaging. Front Oncol 2017; 7:3. [PMID: 28197395 PMCID: PMC5281579 DOI: 10.3389/fonc.2017.00003] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Accepted: 01/05/2017] [Indexed: 12/13/2022] Open
Abstract
Tumors are often characterized by hypoxia, vascular abnormalities, low extracellular pH, increased interstitial fluid pressure, altered choline-phospholipid metabolism, and aerobic glycolysis (Warburg effect). The impact of these tumor characteristics has been investigated extensively in the context of tumor development, progression, and treatment response, resulting in a number of non-invasive imaging biomarkers. More recent evidence suggests that cancer cells undergo metabolic reprograming, beyond aerobic glycolysis, in the course of tumor development and progression. The resulting altered metabolic content in tumors has the ability to affect cell signaling and block cellular differentiation. Additional emerging evidence reveals that the interaction between tumor and stroma cells can alter tumor metabolism (leading to metabolic reprograming) as well as tumor growth and vascular features. This review will summarize previous and current preclinical, non-invasive, multimodal imaging efforts to characterize the tumor microenvironment, including its stromal components and understand tumor-stroma interaction in cancer development, progression, and treatment response.
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Affiliation(s)
- Nirilanto Ramamonjisoa
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Ellen Ackerstaff
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, NY, USA
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21
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Song Y, Su D, Shen Y, Liu H, Wang L. Design and preparation of open circuit potential biosensor for in vitro and in vivo glucose monitoring. Anal Bioanal Chem 2016; 409:161-168. [DOI: 10.1007/s00216-016-9982-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Revised: 09/16/2016] [Accepted: 09/27/2016] [Indexed: 11/29/2022]
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22
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Yang X, Song X, Banerjee SR, Li Y, Byun Y, Liu G, Bhujwalla ZM, Pomper MG, McMahon MT. Developing imidazoles as CEST MRI pH sensors. CONTRAST MEDIA & MOLECULAR IMAGING 2016; 11:304-12. [PMID: 27071959 PMCID: PMC5201433 DOI: 10.1002/cmmi.1693] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Revised: 02/17/2016] [Accepted: 02/22/2016] [Indexed: 12/21/2022]
Abstract
A series of intra-molecular hydrogen bonded imidazoles and related heterocyclic compounds were screened for their N-H chemical exchange saturation transfer (CEST) magnetic resonance imaging (MRI) contrast properties. Of the compounds, imidazole-4,5-dicarboxamides (I45DCs) were found to provide the strongest contrast, with the contrast produced at a large chemical shift from water (7.8 ppm) and strongly dependent on pH. We have tested several probes based on this scaffold, and demonstrated that these probes could be applied for in vivo detection of kidney pH after intravenous administration. Copyright © 2016 John Wiley & Sons, Ltd.
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Affiliation(s)
- Xing Yang
- Russell H. Morgan Department of Radiology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Xiaolei Song
- Russell H. Morgan Department of Radiology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
- F. M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, USA
| | - Sangeeta Ray Banerjee
- Russell H. Morgan Department of Radiology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Yuguo Li
- Russell H. Morgan Department of Radiology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
- F. M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, USA
| | - Youngjoo Byun
- College of Pharmacy, Korea University, Sejong, South Korea
| | - Guanshu Liu
- Russell H. Morgan Department of Radiology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
- F. M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, USA
| | - Zaver M. Bhujwalla
- Russell H. Morgan Department of Radiology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Martin G. Pomper
- Russell H. Morgan Department of Radiology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Michael T. McMahon
- Russell H. Morgan Department of Radiology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
- F. M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, USA
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23
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Flavell RR, von Morze C, Blecha JE, Korenchan DE, Van Criekinge M, Sriram R, Gordon JW, Chen HY, Subramaniam S, Bok RA, Wang ZJ, Vigneron DB, Larson PE, Kurhanewicz J, Wilson DM. Application of Good's buffers to pH imaging using hyperpolarized (13)C MRI. Chem Commun (Camb) 2016; 51:14119-22. [PMID: 26257040 DOI: 10.1039/c5cc05348j] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
N-(2-Acetamido)-2-aminoethanesulfonic acid (ACES), one of Good's buffers, was applied to pH imaging using hyperpolarized (13)C magnetic resonance spectroscopy. Rapid NMR- and MRI-based pH measurements were obtained by exploiting the sensitive pH-dependence of its (13)C chemical shift within the physiologic range.
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Affiliation(s)
- Robert R Flavell
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, California 94158, USA.
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24
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Korenchan DE, Flavell RR, Baligand C, Sriram R, Neumann K, Sukumar S, VanBrocklin H, Vigneron DB, Wilson DM, Kurhanewicz J. Dynamic nuclear polarization of biocompatible (13)C-enriched carbonates for in vivo pH imaging. Chem Commun (Camb) 2016; 52:3030-3. [PMID: 26792559 PMCID: PMC4864526 DOI: 10.1039/c5cc09724j] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
A hyperpolarization technique using carbonate precursors of biocompatible molecules was found to yield high concentrations of hyperpolarized (13)C bicarbonate in solution. This approach enabled large signal gains for low-toxicity hyperpolarized (13)C pH imaging in a phantom and in vivo in a murine model of prostate cancer.
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Affiliation(s)
- D E Korenchan
- UC Berkeley-UCSF Graduate Program in Bioengineering, University of California, Berkeley and University of California, San Francisco, California, USA. and Department of Radiology and Biomedical Imaging, University of California, San Francisco, California, USA.
| | - R R Flavell
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, California, USA.
| | - C Baligand
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, California, USA.
| | - R Sriram
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, California, USA.
| | - K Neumann
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, California, USA.
| | - S Sukumar
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, California, USA.
| | - H VanBrocklin
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, California, USA.
| | - D B Vigneron
- UC Berkeley-UCSF Graduate Program in Bioengineering, University of California, Berkeley and University of California, San Francisco, California, USA. and Department of Radiology and Biomedical Imaging, University of California, San Francisco, California, USA.
| | - D M Wilson
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, California, USA.
| | - J Kurhanewicz
- UC Berkeley-UCSF Graduate Program in Bioengineering, University of California, Berkeley and University of California, San Francisco, California, USA. and Department of Radiology and Biomedical Imaging, University of California, San Francisco, California, USA.
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25
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Chaumeil MM, Lupo JM, Ronen SM. Magnetic Resonance (MR) Metabolic Imaging in Glioma. Brain Pathol 2015; 25:769-80. [PMID: 26526945 PMCID: PMC8029127 DOI: 10.1111/bpa.12310] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Accepted: 08/25/2015] [Indexed: 12/25/2022] Open
Abstract
This review is focused on describing the use of magnetic resonance (MR) spectroscopy for metabolic imaging of brain tumors. We will first review the MR metabolic imaging findings generated from preclinical models, focusing primarily on in vivo studies, and will then describe the use of metabolic imaging in the clinical setting. We will address relatively well-established (1) H MRS approaches, as well as (31) P MRS, (13) C MRS and emerging hyperpolarized (13) C MRS methodologies, and will describe the use of metabolic imaging for understanding the basic biology of glioma as well as for improving the characterization and monitoring of brain tumors in the clinic.
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Affiliation(s)
| | - Janine M. Lupo
- Department of Radiology and Biomedical ImagingMission Bay Campus
| | - Sabrina M. Ronen
- Department of Radiology and Biomedical ImagingMission Bay Campus
- Brain Tumor Research CenterUniversity of CaliforniaSan FranciscoCA
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26
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Pacheco-Torres J, Mukherjee N, Walko M, López-Larrubia P, Ballesteros P, Cerdan S, Kocer A. Image guided drug release from pH-sensitive Ion channel-functionalized stealth liposomes into an in vivo glioblastoma model. NANOMEDICINE-NANOTECHNOLOGY BIOLOGY AND MEDICINE 2015; 11:1345-54. [DOI: 10.1016/j.nano.2015.03.014] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2014] [Revised: 03/03/2015] [Accepted: 03/29/2015] [Indexed: 01/11/2023]
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27
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Magnetic resonance spectroscopy and imaging on fresh human brain tumor biopsies at microscopic resolution. Anal Bioanal Chem 2015; 407:6771-80. [PMID: 26123440 DOI: 10.1007/s00216-015-8847-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Revised: 06/04/2015] [Accepted: 06/10/2015] [Indexed: 12/16/2022]
Abstract
The metabolic composition and concentration knowledge provided by magnetic resonance spectroscopy (MRS) liquid and high-resolution magic angle spinning spectroscopy (HR-MAS) has a relevant impact in clinical practice during magnetic resonance imaging (MRI) monitoring of human tumors. In addition, the combination of morphological and chemical information by MRI and MRS has been particularly useful for diagnosis and prognosis of tumor evolution. MRI spatial resolution reachable in human beings is limited for safety reasons and the demanding necessary conditions are only applicable on experimental model animals. Nevertheless, MRS and MRI can be performed on human biopsies at high spatial resolution, enough to allow a direct correlation between the chemical information and the histological features observed in such biopsies. Although HR-MAS is nowadays a well-established technique for spectroscopic analysis of tumor biopsies, with this approach just a mean metabolic profile of the whole sample can be obtained and thus the high histological heterogeneity of some important tumors is mostly neglected. The value of metabolic HR-MAS data strongly depends on a wide statistical analysis and usually the microanatomical rationale for the correlation between histology and spectroscopy is lost. We present here a different approach for the combined use of MRI and MRS on fresh human brain tumor biopsies with native contrast. This approach has been designed to achieve high spatial (18 × 18 × 50 μm) and spectral (0.031 μL) resolution in order to obtain as much spatially detailed morphological and metabolical information as possible without any previous treatment that can alter the sample. The preservation of native tissue conditions can provide information that can be translated to in vivo studies and additionally opens the possibility of performing other techniques to obtain complementary information from the same sample.
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28
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Penet MF, Krishnamachary B, Chen Z, Jin J, Bhujwalla ZM. Molecular imaging of the tumor microenvironment for precision medicine and theranostics. Adv Cancer Res 2015; 124:235-56. [PMID: 25287691 DOI: 10.1016/b978-0-12-411638-2.00007-0] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Morbidity and mortality from cancer and their associated conditions and treatments continue to extract a heavy social and economic global burden despite the transformative advances in science and technology in the twenty-first century. In fact, cancer incidence and mortality are expected to reach pandemic proportions by 2025, and costs of managing cancer will escalate to trillions of dollars. The inability to establish effective cancer treatments arises from the complexity of conditions that exist within tumors, the plasticity and adaptability of cancer cells coupled with their ability to escape immune surveillance, and the co-opted stromal cells and microenvironment that assist cancer cells in survival. Stromal cells, although destroyed together with cancer cells, have an ever-replenishing source that can assist in resurrecting tumors from any residual cancer cells that may survive treatment. The tumor microenvironment landscape is a continually changing landscape, with spatial and temporal heterogeneities that impact and influence cancer treatment outcome. Importantly, the changing landscape of the tumor microenvironment can be exploited for precision medicine and theranostics. Molecular and functional imaging can play important roles in shaping and selecting treatments to match this landscape. Our purpose in this review is to examine the roles of molecular and functional imaging, within the context of the tumor microenvironment, and the feasibility of their applications for precision medicine and theranostics in humans.
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Affiliation(s)
- Marie-France Penet
- JHU ICMIC Program, Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA; Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Balaji Krishnamachary
- JHU ICMIC Program, Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Zhihang Chen
- JHU ICMIC Program, Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Jiefu Jin
- JHU ICMIC Program, Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Zaver M Bhujwalla
- JHU ICMIC Program, Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA; Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
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Extracellular acidity, a "reappreciated" trait of tumor environment driving malignancy: perspectives in diagnosis and therapy. Cancer Metastasis Rev 2015; 33:823-32. [PMID: 24984804 DOI: 10.1007/s10555-014-9506-4] [Citation(s) in RCA: 112] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Tumors are ecosystems which develop from stem cells endowed with unlimited self-renewal capability and genetic instability, under the effects of mutagenesis and natural selection imposed by environmental changes. Abnormal vascularization, reduced lymphatic network, uncontrolled cell growth frequently associated with hypoxia, and extracellular accumulation of glucose metabolites even in the presence of an adequate oxygen level are all factors contributing to reduce pH in the extracellular space of tumors. Evidence is accumulating that acidity is associated with a poor prognosis and participates actively to tumor progression. This review addresses some of the most experimental evidences providing that acidity of tumor environment facilitates local invasiveness and metastatic dissemination, independently from hypoxia, with which acidity is often but not always associated. Clinical investigations have also shown that tumors with acidic environment are associated with resistance to chemotherapy and radiation-induced apoptosis, suppression of cytotoxic lymphocytes, and natural killer cells tumoricidal activity. Therefore, new technologies for functional and molecular imaging as well as strategies directed to target low extracellular pH and low pH-adapted tumor cells might represent important issues in oncology.
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Wang L, Fan Z, Zhang J, Changyi Y, Huang C, Gu Y, Xu Z, Tang Z, Lu W, Wei X, Li C. Evaluating tumor metastatic potential by imaging intratumoral acidosisviapH-activatable near-infrared fluorescent probe. Int J Cancer 2014; 136:E107-16. [DOI: 10.1002/ijc.29153] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2014] [Revised: 08/12/2014] [Accepted: 08/15/2014] [Indexed: 12/16/2022]
Affiliation(s)
- Lu Wang
- Key Laboratory of Smart Drug Delivery; Ministry of Education, School of Pharmacy, Fudan University; Shanghai 201203 China
| | - Zhichao Fan
- Med-X Research Institute and School of Biomedical Engineering; Shanghai Jiao Tong University; Shanghai 200030 China
| | - Jingye Zhang
- Key Laboratory of Smart Drug Delivery; Ministry of Education, School of Pharmacy, Fudan University; Shanghai 201203 China
| | - Yinzhi Changyi
- Key Laboratory of Smart Drug Delivery; Ministry of Education, School of Pharmacy, Fudan University; Shanghai 201203 China
| | - Cuiyun Huang
- Key Laboratory of Smart Drug Delivery; Ministry of Education, School of Pharmacy, Fudan University; Shanghai 201203 China
| | - Yanjuan Gu
- Department of Applied Biology and Chemical Technology; The Hong Kong Polytechnic University, Hung Hom; Kowloon Hong Kong China
| | - Ziyao Xu
- Key Laboratory of Smart Drug Delivery; Ministry of Education, School of Pharmacy, Fudan University; Shanghai 201203 China
| | - Zhijia Tang
- Key Laboratory of Smart Drug Delivery; Ministry of Education, School of Pharmacy, Fudan University; Shanghai 201203 China
| | - Weiyue Lu
- Key Laboratory of Smart Drug Delivery; Ministry of Education, School of Pharmacy, Fudan University; Shanghai 201203 China
| | - Xunbin Wei
- Med-X Research Institute and School of Biomedical Engineering; Shanghai Jiao Tong University; Shanghai 200030 China
| | - Cong Li
- Key Laboratory of Smart Drug Delivery; Ministry of Education, School of Pharmacy, Fudan University; Shanghai 201203 China
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Effect of acute hyperglycemia on moderately hypothermic GL261 mouse glioma monitored by T1-weighted DCE MRI. MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE 2014; 28:119-26. [PMID: 24916487 DOI: 10.1007/s10334-014-0447-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2013] [Revised: 04/15/2014] [Accepted: 04/15/2014] [Indexed: 10/25/2022]
Abstract
OBJECTIVE We sought to evaluate the effects of acute hyperglycemia induced by intraperitoneal injection of glucose (2.7 g/kg) on vascular delivery to GL261 mouse gliomas kept at moderate hypothermia (~30 °C). MATERIALS AND METHODS Seven GL261 glioma-bearing mice were studied by T1-weighted DCE MRI before and after an injection of glucose (n = 4) or saline (n = 3). Maximum relative contrast enhancement (RCE) and initial area under the enhancement curve (IAUC) were determined in each pixel. RESULTS The mean tumor parameter values showed no significant changes after injecting either saline (RCE -5.9 ± 5.0 %; IAUC -3.7 ± 3.6 %) or glucose (RCE -1.6 ± 9.0 %; IAUC +0.6 ± 6.4 %). Pixel-by-pixel analysis revealed small post-injection changes in RCE and IAUC between the glucose and saline groups, all within 13 % range of their baseline values. CONCLUSION Perturbing the metabolism of GL261 tumors kept at moderate hypothermia with hyperglycemia did not induce significant changes in the permeability/perfusion of these tumors. This is relevant for future studies with this model since regional differences in glucose accumulation could thus reflect basal heterogeneities in vasculature and/or metabolism of GL261 tumors.
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32
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Pilot study of Iopamidol-based quantitative pH imaging on a clinical 3T MR scanner. MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE 2014; 27:477-85. [DOI: 10.1007/s10334-014-0433-8] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2013] [Revised: 01/24/2014] [Accepted: 01/27/2014] [Indexed: 12/22/2022]
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33
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Abaza M, Luqmani YA. The influence of pH and hypoxia on tumor metastasis. Expert Rev Anticancer Ther 2013; 13:1229-42. [PMID: 24099530 DOI: 10.1586/14737140.2013.843455] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Rapid malignant proliferation, prior to effective tumor neoangiogenesis, creates a microenvironment around solid cancers, which is predominantly hypoxic and characterized by a high interstitial fluid pressure. Presumably as an adaptive response, tumor cells favor metabolic activity with apparently inefficient energy output, and production of intermediates that promote cellular replication, preferentially through anaerobic glycolysis, a phenomenon that persists even in re-established normoxic conditions (anomalously referred to as 'aerobic glycolysis'). Extrusion of the consequently excessive accumulation of lactate and protons decreases extracellular pH, leading to a microenvironment considered conducive to promotion of tumor motility, invasion and metastasis, and one that will invariably influence response to drug treatment. This review will critically assess the evidence forming the basis of current understanding of the precise pH conditions in the extracellular tumor matrix, its regulation by cancer cells and relationship with hypoxia, its relevance to malignant progression and its exploitation for therapeutic advantage.
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Affiliation(s)
- Mariam Abaza
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Kuwait University, PO Box 24923, Safat 13110, Kuwait
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34
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Al-Husari M, Webb SD. Theoretical predictions of lactate and hydrogen ion distributions in tumours. PLoS One 2013; 8:e72020. [PMID: 23991029 PMCID: PMC3749110 DOI: 10.1371/journal.pone.0072020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2012] [Accepted: 07/11/2013] [Indexed: 11/30/2022] Open
Abstract
High levels of lactate and H(+)-ions play an important role in the invasive and metastatic cascade of some tumours. We develop a mathematical model of cellular pH regulation focusing on the activity of the Na(+)/H(+) exchanger (NHE) and the lactate/H(+) symporter (MCT) to investigate the spatial correlations of extracellular lactate and H(+)-ions. We highlight a crucial role for blood vessel perfusion rates in determining the spatial correlation between these two cations. We also predict critical roles for blood lactate, the activity of the MCTs and NHEs on the direction of the cellular pH gradient in the tumour. We also incorporate experimentally determined heterogeneous distributions of the NHE and MCT transporters. We show that this can give rise to a higher intracellular pH and a lower intracellular lactate but does not affect the direction of the reversed cellular pH gradient or redistribution of protons away from the glycolytic source. On the other hand, including intercellular gap junction communication in our model can give rise to a reversed cellular pH gradient and can influence the levels of pH.
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Affiliation(s)
- Maymona Al-Husari
- Department of Mathematics and Statistics, University of Strathclyde, Glasgow, United Kingdom
| | - Steven D. Webb
- MRC Centre for Drug Safety Science, Department of Molecular and Clinical Pharmacology, Institute of Translational Medicine, The University of Liverpool, Liverpool, United Kingdom
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35
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Penet MF, Artemov D, Farahani K, Bhujwalla ZM. MR - eyes for cancer: looking within an impenetrable disease. NMR IN BIOMEDICINE 2013; 26:745-55. [PMID: 23784955 PMCID: PMC3690531 DOI: 10.1002/nbm.2980] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2012] [Revised: 03/28/2013] [Accepted: 05/09/2013] [Indexed: 05/16/2023]
Abstract
Probe development is a critical component in cancer imaging, and novel probes are making major inroads in several aspects of cancer detection and image-guided treatments. Intrinsic MR probes such as signals from metabolites and their chemical shifts have been used for more than a decade to understand cancer physiology and metabolism. Through the integration of technology, molecular biology, and chemistry, the last few years have witnessed an explosion of extrinsic probes for molecular and functional imaging of cancer that, together with techniques such as CEST and hyperpolarization, have significantly expanded the repertoire of MR techniques in basic and translational investigations of many different aspects of cancer. Furthermore, incorporation of MR probes into multifunctional nanoparticles and multimodality imaging platforms have opened new opportunities for MR in image-guided diagnosis and therapy of cancer. Here we have provided an overview of recent innovations that have occurred in the development of MRI probes for molecular and functional imaging of cancer. Although most of these novel probes are not clinically available, they offer significant promise for future translational applications. In this review, we have highlighted the areas of future development that are likely to have a profound impact on cancer detection and treatment.
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Affiliation(s)
- Marie-France Penet
- JHU ICMIC Program, Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Dmitri Artemov
- JHU ICMIC Program, Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
- Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Keyvan Farahani
- Image Guided Interventions Branch, Cancer Imaging Program, National Cancer Institute, Bethesda MD, USA
| | - Zaver M. Bhujwalla
- JHU ICMIC Program, Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
- Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
- Correspondence to: Zaver M. Bhujwalla, Ph.D., Department of Radiology, Johns Hopkins University School of Medicine, 208C Traylor Building, 720 Rutland Avenue, Baltimore, MD 21205, USA., Phone: 410-955-9698, Fax: 410-614-1948,
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36
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Huang X, Huang G, Zhang S, Sagiyama K, Togao O, Ma X, Wang Y, Li Y, Soesbe TC, Sumer BD, Takahashi M, Sherry AD, Gao J. Multi-Chromatic pH-Activatable19F-MRI Nanoprobes with Binary ON/OFF pH Transitions and Chemical-Shift Barcodes. Angew Chem Int Ed Engl 2013. [DOI: 10.1002/ange.201301135] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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37
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Huang X, Huang G, Zhang S, Sagiyama K, Togao O, Ma X, Wang Y, Li Y, Soesbe TC, Sumer BD, Takahashi M, Sherry AD, Gao J. Multi-chromatic pH-activatable 19F-MRI nanoprobes with binary ON/OFF pH transitions and chemical-shift barcodes. Angew Chem Int Ed Engl 2013; 52:8074-8. [PMID: 23788453 DOI: 10.1002/anie.201301135] [Citation(s) in RCA: 92] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2013] [Revised: 03/26/2013] [Indexed: 12/16/2022]
Affiliation(s)
- Xiaonan Huang
- Department of Pharmacology, Harold C. Simmons Comprehensive Cancer Center, UT Southwestern Medical Center at Dallas, 5323 Harry Hines Blvds, Dallas, TX 75390, USA
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38
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Acidic pH via NF-κB favours VEGF-C expression in human melanoma cells. Clin Exp Metastasis 2013; 30:957-67. [PMID: 23784694 DOI: 10.1007/s10585-013-9595-4] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2013] [Accepted: 06/03/2013] [Indexed: 12/19/2022]
Abstract
Malignant melanomas are characterized by the ability of early metastatic dissemination to regional lymph nodes and the detection of sentinel lymph node metastases serves as an important prognostic parameter. There is clear evidence that melanoma cells and stromal cells of tumor environment can induce lymphangiogenesis, e.g. growth of lymphatic vessels, and this phenomenon is correlated with lymph node metastases. Vascular endothelial growth factor (VEGF) C represents the most potent and well-recognized lymphangiogenic growth factor secreted in tumor milieu by melanoma cells and tumor-associated macrophages, however the mechanism underlying VEGF-C secretion is not completely understood. We demonstrate that an acidic extracellular pH promotes the expression of VEGF-C in A375P melanoma cells and in melanoma cells isolated from a human spontaneous metastatic lesion, through the NF-κB transcription factor. We also demonstrate that esomeprazole, a proton pump inhibitor which requires acidosis to be activated, is able to prevent VEGF-C expression in acidic melanoma cells by interfering with NF-κB activation. Furthermore, we show that esomeprazole abrogates the enhanced VEGF-C expression in tumor cells grown in a acidic medium and stimulated by IL-1β. On the whole, the present study reveals that acidity may be considered a strong promoter of VEGF-C expression in melanoma cells and provides a new pharmacological target to limit the development of tumor lymphangiogenesis.
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39
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Lutz NW, Le Fur Y, Chiche J, Pouysségur J, Cozzone PJ. Quantitative in vivo characterization of intracellular and extracellular pH profiles in heterogeneous tumors: a novel method enabling multiparametric pH analysis. Cancer Res 2013; 73:4616-28. [PMID: 23752692 DOI: 10.1158/0008-5472.can-13-0767] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Acid production and transport are currently being studied to identify new targets for efficient cancer treatment, as subpopulations of tumor cells frequently escape conventional therapy owing to their particularly acidic tumor microenvironment. Heterogeneity in intracellular and extracellular tumor pH (pHi, pHe) has been reported, but none of the methods currently available for measuring tissue pH provides quantitative parameters characterizing pH distribution profiles in tissues. To this intent, we present here a multiparametric, noninvasive approach based on in vivo (31)P nuclear magnetic resonance (NMR) spectroscopy and its application to mouse tumor xenografts. First, localized (31)P NMR spectrum signals of pHi and pHe reporter molecules [inorganic phosphate (Pi) and 3-aminopropylphosphonate (3-APP), respectively] were transformed into pH curves using established algorithms. Although Pi is an endogenous compound, 3-APP had to be injected intraperitoneally. Then, we developed algorithms for the calculation of six to eight quantitative pH parameters from the digital points of each pH curve obtained. For this purpose, each pH distribution profile was approximated as a histogram, and intensities were corrected for the nonlinearity between chemical-shift and pH.
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Affiliation(s)
- Norbert W Lutz
- Centre de Résonance Magnétique Biologique et Médicale (CRMBM), UMR 7339, Faculté de Médecine de la Timone, Centre National de la Recherche Scientifique (CNRS), Aix-Marseille Université, Marseille, France.
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40
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Al-Husari M, Webb SD. Regulation of tumour intracellular pH: a mathematical model examining the interplay between H+ and lactate. J Theor Biol 2013; 322:58-71. [PMID: 23340437 DOI: 10.1016/j.jtbi.2013.01.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2012] [Revised: 10/31/2012] [Accepted: 01/03/2013] [Indexed: 02/04/2023]
Abstract
Non-invasive measurements of pH have shown that both tumour and normal cells have intracellular pH (pHi) that lies on the alkaline side of neutrality (7.1-7.2). However, extracellular pH (pHe) is reported to be more acidic in some tumours compared to normal tissues. Many cellular processes and therapeutic agents are known to be tightly pH dependent which makes the study of intracellular pH regulation of paramount importance. We develop a mathematical model that examines the role of various membrane-based ion transporters in tumour pH regulation, in particular, with a focus on the interplay between lactate and H(+) ions and whether the lactate/H(+) symporter activity is sufficient to give rise to the observed reversed pH gradient that is seen is some tumours. Using linear stability analysis and numerical methods, we are able to gain a clear understanding of the relationship between lactate and H(+) ions. We extend this analysis using perturbation techniques to specifically examine a rapid change in H(+)-ion concentrations relative to variations in lactate. We then perform a parameter sensitivity analysis to explore solution robustness to parameter variations. An important result from our study is that a reversed pH gradient is possible in our system but for unrealistic parameter estimates-pointing to the possible involvement of other mechanisms in cellular pH gradient reversal, for example acidic vesicles, lysosomes, golgi and endosomes.
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Affiliation(s)
- Maymona Al-Husari
- Department of Mathematics and Statistics, University of Strathclyde, Glasgow G1 1XH, UK
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41
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Lee YJ, Kang HC, Hu J, Nichols JW, Jeon YS, Bae YH. pH-Sensitive polymeric micelle-based pH probe for detecting and imaging acidic biological environments. Biomacromolecules 2012; 13:2945-51. [PMID: 22861824 DOI: 10.1021/bm300985r] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
To overcome the limitations of monomeric pH probes for acidic tumor environments, this study designed a mixed micelle pH probe composed of polyethylene glycol (PEG)-b-poly(L-histidine) (PHis) and PEG-b-poly(L-lactic acid) (PLLA), which is well-known as an effective antitumor drug carrier. Unlike monomeric histidine and PHis derivatives, the mixed micelles can be structurally destabilized by changes in pH, leading to a better pH sensing system in nuclear magnetic resonance (NMR) techniques. The acidic pH-induced transformation of the mixed micelles allowed pH detection and pH mapping of 0.2-0.3 pH unit differences by pH-induced "on/off"-like sensing of NMR and magnetic resonance spectroscopy. The micellar pH probes sensed pH differences in nonbiological phosphate buffer and biological buffers such as cell culture medium and rat whole blood. In addition, the pH-sensing ability of the mixed micelles was not compromised by loaded doxorubicin. In conclusion, PHis-based micelles could have potential as a tool to simultaneously treat and map the pH of solid tumors in vivo.
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Affiliation(s)
- Young Ju Lee
- Department of Pharmaceutics and Pharmaceutical Chemistry, The University of Utah, 421 Wakara Way, Suite 318, Salt Lake City, Utah 84108, USA
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42
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In Vivo Magnetic Resonance Spectroscopic Imaging and Ex Vivo Quantitative Neuropathology by High Resolution Magic Angle Spinning Proton Magnetic Resonance Spectroscopy. ACTA ACUST UNITED AC 2012. [DOI: 10.1007/7657_2011_31] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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43
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McIntyre DJO, Madhu B, Lee SH, Griffiths JR. Magnetic resonance spectroscopy of cancer metabolism and response to therapy. Radiat Res 2012; 177:398-435. [PMID: 22401303 DOI: 10.1667/rr2903.1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Magnetic resonance spectroscopy allows noninvasive in vivo measurements of biochemical information from living systems, ranging from cultured cells through experimental animals to humans. Studies of biopsies or extracts offer deeper insights by detecting more metabolites and resolving metabolites that cannot be distinguished in vivo. The pharmacokinetics of certain drugs, especially fluorinated drugs, can be directly measured in vivo. This review briefly describes these methods and their applications to cancer metabolism, including glycolysis, hypoxia, bioenergetics, tumor pH, and tumor responses to radiotherapy and chemotherapy.
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Affiliation(s)
- Dominick J O McIntyre
- Cancer Research UK, Cambridge Research Institute, Li Ka Shing Centre, Robinson Way, Cambridge CB2 0RE, UK.
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44
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Yang Y, Schühle DT, Dai G, Alford J, Caravan P. 1H chemical shift magnetic resonance imaging probes with high sensitivity for multiplex imaging. CONTRAST MEDIA & MOLECULAR IMAGING 2012; 7:276-9. [PMID: 22434641 PMCID: PMC3321363 DOI: 10.1002/cmmi.490] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Proton-based chemical shift imaging probes were encapsulated inside nano-carriers to increase the sensivitity of the reporters. Co-encapsulation with a relaxation agent results in improved sensitivity and suppresses background signals. Simultaneous imaging of different chemical shift reporters allows multiplexed detection.
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Affiliation(s)
- Yan Yang
- A.A. Martinos Center for Biomedical Imaging Massachusetts General Hospital, Harvard Medical School 149, 13th Street, Suite 2301, Charlestown, MA 02129, USA. Fax: (+1) 617-726-7422
- Zhongnan Hospital of Wuhan University, Donghu Road 169, Wuhan, Hubei Province, China
| | - Daniel T. Schühle
- A.A. Martinos Center for Biomedical Imaging Massachusetts General Hospital, Harvard Medical School 149, 13th Street, Suite 2301, Charlestown, MA 02129, USA. Fax: (+1) 617-726-7422
| | - Guangping Dai
- A.A. Martinos Center for Biomedical Imaging Massachusetts General Hospital, Harvard Medical School 149, 13th Street, Suite 2301, Charlestown, MA 02129, USA. Fax: (+1) 617-726-7422
| | - Jamu Alford
- A.A. Martinos Center for Biomedical Imaging Massachusetts General Hospital, Harvard Medical School 149, 13th Street, Suite 2301, Charlestown, MA 02129, USA. Fax: (+1) 617-726-7422
| | - Peter Caravan
- A.A. Martinos Center for Biomedical Imaging Massachusetts General Hospital, Harvard Medical School 149, 13th Street, Suite 2301, Charlestown, MA 02129, USA. Fax: (+1) 617-726-7422
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45
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Penet MF, Chen Z, Bhujwalla ZM. MRI of metastasis-permissive microenvironments. Future Oncol 2012; 7:1269-84. [PMID: 22044202 DOI: 10.2217/fon.11.114] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
One of the earliest documented observations of the importance of the microenvironment in metastasis was made by Stephen Paget in 1889. More than a century later, the metastatic cascade remains a major cause of mortality from cancer. Cancer meets the criterion of a successful organization that is able to survive by adapting to changing environments. In fact, the tumor microenvironment and stroma are co-opted and shaped by cancer cells to derive a survival advantage. Cohesive strategies integrating advances in molecular biology and chemistry, with noninvasive multimodality imaging, provide new insights into the role of the tumor microenvironment in promoting metastasis from primary tumors as well as insights into environments that attract and permit cancer cells to establish colonies in distant organs. This article provides an overview of molecular and functional imaging characterization of microenvironments that can promote or permit cancer cells to metastasize and the microenvironmental characteristics of distant metastases.
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Affiliation(s)
- Marie-France Penet
- JHU In vivo Cellular & Molecular Imaging Center, The Russell H. Morgan Department of Radiology & Radiological Science, Baltimore, MD, USA.
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46
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Gallagher FA, Kettunen MI, Brindle KM. Imaging pH with hyperpolarized 13C. NMR IN BIOMEDICINE 2011; 24:1006-1015. [PMID: 21812047 DOI: 10.1002/nbm.1742] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2010] [Revised: 03/23/2011] [Accepted: 04/05/2011] [Indexed: 05/31/2023]
Abstract
pH is a fundamental physiological parameter that is tightly controlled by endogenous buffers. The acid-base balance is altered in many disease states, such as inflammation, ischemia and cancer. Despite the importance of pH, there are currently no routine methods for imaging the spatial distribution of pH in humans. The enormous gain in sensitivity afforded by dynamic nuclear polarization (DNP) has provided a novel way in which to image tissue pH using MR, which has the potential to be translated into the clinic. This review explores the advantages and disadvantages of current pH imaging techniques and how they compare with DNP-based approaches for the measurement and imaging of pH with hyperpolarized (13)C. Intravenous injection of hyperpolarized (13)C-labeled bicarbonate results in the rapid production of hyperpolarized (13)CO(2) in the reaction catalyzed by carbonic anhydrase. As this reaction is close to equilibrium in the body and is pH dependent, the ratio of the (13)C signal intensities from H(13)CO(3)(-) and (13)CO(2), measured using MRS, can be used to calculate pH in vivo. The application of this technique to a murine tumor model demonstrated that it measured predominantly extracellular pH and could be mapped in the animal using spectroscopic imaging techniques. A second approach has been to use the production of hyperpolarized (13)CO(2) from hyperpolarized [1-(13)C]pyruvate to measure predominantly intracellular pH. In tissues with a high aerobic capacity, such as the heart, the hyperpolarized [1-(13)C]pyruvate undergoes rapid oxidative decarboxylation, catalyzed by intramitochondrial pyruvate dehydrogenase. Provided that there is sufficient carbonic anhydrase present to catalyze the rapid equilibration of the hyperpolarized (13)C label between CO(2) and bicarbonate, the ratio of their resonance intensities may again be used to estimate pH, which, in this case, is predominantly intracellular. As both pyruvate and bicarbonate are endogenous molecules they have the potential to image tissue pH in the clinic.
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Affiliation(s)
- Ferdia A Gallagher
- Cancer Research UK Cambridge Research Institute, Li Ka Shing Centre, and Department of Biochemistry, University of Cambridge, Cambridge, UK.
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47
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Hashim AI, Zhang X, Wojtkowiak JW, Martinez GV, Gillies RJ. Imaging pH and metastasis. NMR IN BIOMEDICINE 2011; 24:582-91. [PMID: 21387439 PMCID: PMC3740268 DOI: 10.1002/nbm.1644] [Citation(s) in RCA: 202] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2010] [Revised: 09/30/2010] [Accepted: 10/19/2010] [Indexed: 05/05/2023]
Abstract
Metastasis is a multistep process that culminates in the spread of cells from a primary tumor to a distant site or organs. For tumor cells to be able to metastasize, they have to locally invade through basement membrane into the lymphatic and the blood vasculatures. Eventually they extravasate from the blood and colonize in the secondary organ. This process involves multiple interactions between the tumor cells and their microenvironments. The microenvironment surrounding tumors has a significant impact on tumor development and progression. A key factor in the microenvironment is an acidic pH. The extracellular pH of solid tumors is more acidic in comparison to normal tissue as a consequence of high glycolysis and poor perfusion. It plays an important role in almost all steps of metastasis. The past decades have seen development of technologies to non-invasively measure intra- and/or extracellular pH. Most successful measurements are MR-based, and sensitivity and accuracy have dramatically improved. Quantitatively imaging the distribution of acidity helps us understand the role of the tumor microenvironment in cancer progression. The present review discusses different MR methods in measuring tumor pH along with emphasizing the importance of extracelluar tumor low pH on different steps of metastasis; more specifically focusing on epithelial-to-mesenchymal transition (EMT), and anti cancer immunity.
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Affiliation(s)
- Arig Ibrahim Hashim
- Department of Imaging research, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA
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48
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Bell LK, Ainsworth NL, Lee SH, Griffiths JR. MRI & MRS assessment of the role of the tumour microenvironment in response to therapy. NMR IN BIOMEDICINE 2011; 24:612-35. [PMID: 21567513 DOI: 10.1002/nbm.1720] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2010] [Revised: 02/28/2011] [Accepted: 03/07/2011] [Indexed: 05/30/2023]
Abstract
MRI and MRS techniques are being applied to the characterisation of various aspects of the tumour microenvironment and to the assessment of tumour response to therapy. For example, kinetic parameters describing tumour blood vessel flow and permeability can be derived from dynamic contrast-enhanced MRI data and have been correlated with a positive tumour response to antivascular therapies. The ongoing development and validation of noninvasive, high-resolution anatomical/molecular MR techniques will equip us with the means to detect specific tumour biomarkers early on, and then to monitor the efficacy of cancer treatments efficiently and reliably, all within a clinically relevant time frame. Reliable tumour microenvironment imaging biomarkers will provide obvious advantages by enabling tumour-specific treatment tailoring and potentially improving patient outcome. However, for routine clinical application across many disease types, such imaging biomarkers must be quantitative, robust, reproducible, sufficiently sensitive and cost-effective. These characteristics are all difficult to achieve in practice, but image biomarker development and validation have been greatly facilitated by an increasing number of pertinent preclinical in vivo cancer models. Emphasis must now be placed on discovering whether the preclinical results translate into an improvement in patient care and, therefore, overall survival.
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Affiliation(s)
- Leanne K Bell
- Cancer Research UK, Cambridge Research Institute, Li Ka Shing Centre, Cambridge, UK.
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49
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Abstract
The adaptability and the genomic plasticity of cancer cells, and the interaction between the tumor microenvironment and co-opted stromal cells, coupled with the ability of cancer cells to colonize distant organs, contribute to the frequent intractability of cancer. It is becoming increasingly evident that personalized molecular targeting is necessary for the successful treatment of this multifaceted and complex disease. Noninvasive imaging modalities such as magnetic resonance (MR), positron emission tomography (PET), and single-photon emission computed tomography (SPECT) are filling several important niches in this era of targeted molecular medicine, in applications that span from bench to bedside. In this review we focus on noninvasive magnetic resonance spectroscopy (MRS) and spectroscopic imaging (MRSI) and their roles in future personalized medicine in cancer. Diagnosis, the identification of the most effective treatment, monitoring treatment delivery, and response to treatment are some of the broad areas into which MRS techniques can be integrated to improve treatment outcomes. The development of novel probes for molecular imaging--in combination with a slew of functional imaging capabilities--makes MRS techniques, especially in combination with other imaging modalities, valuable in cancer drug discovery and basic cancer research.
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Affiliation(s)
- Kristine Glunde
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
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50
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Grillon E, Farion R, Fablet K, De Waard M, Tse CM, Donowitz M, Rémy C, Coles JA. The spatial organization of proton and lactate transport in a rat brain tumor. PLoS One 2011; 6:e17416. [PMID: 21390324 PMCID: PMC3044751 DOI: 10.1371/journal.pone.0017416] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2010] [Accepted: 02/01/2011] [Indexed: 12/20/2022] Open
Abstract
Tumors create a heterogeneous acidic microenvironment which assists their growth and which must be taken into account in the design of drugs and their delivery. In addition, the acidic extracellular pH (pHe) is itself exploited in several experimental techniques for drug delivery. The way the acidity is created is not clear. We report here the spatial organization of key proton-handling proteins in C6 gliomas in rat brain. The mean profiles across the tumor rim of the Na+/H+ exchanger NHE1, and the lactate-H+ cotransporter MCT1, both showed peaks. NHE1, which is important for extension and migration of cells in vitro, showed a peak 1.55 times higher than in extratumoural tissue at 0.33 mm from the edge. MCT1 had a broader peak, further into the tumor (maximum 1.76 fold at 1.0 mm from the edge). In contrast, MCT4 and the carbonic anhydrase CAIX, which are associated with hypoxia, were not significantly upregulated in the rim. The spatial distribution of MCT4 was highly correlated with that of CAIX, suggesting that their expression is regulated by the same factors. Since protons extruded by NHE1 diffuse away through extracellular clefts, NHE1 requires a continuous source of intracellular protons. From the stoichiometries of metabolic pathways that produce or consume H+, and the greater availability of glucose compared to oxygen in most parts of a tumor, we support the classic view that most of the net proton efflux from C6 gliomas originates in glycolytic formation of lactate and H+ inside the tumor, but add that some lactate is taken up into cells in the rim on MCT1, and some lactate diffuses away, leaving its associated protons available to re-enter cells for extrusion on NHE1. Therapeutic inhibition of NHE1, MCT1 or CAIX is predicted to affect different parts of a tumor.
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Affiliation(s)
- Emmanuelle Grillon
- Unit 836, Institut National de la Santé et de la Recherche Médicale, La Tronche, Isère, France
- Grenoble Institut des Neurosciences, Université Joseph Fourier, Grenoble, France
| | - Régine Farion
- Unit 836, Institut National de la Santé et de la Recherche Médicale, La Tronche, Isère, France
- Grenoble Institut des Neurosciences, Université Joseph Fourier, Grenoble, France
| | - Katell Fablet
- Unit 836, Institut National de la Santé et de la Recherche Médicale, La Tronche, Isère, France
- Grenoble Institut des Neurosciences, Université Joseph Fourier, Grenoble, France
| | - Michel De Waard
- Unit 836, Institut National de la Santé et de la Recherche Médicale, La Tronche, Isère, France
- Grenoble Institut des Neurosciences, Université Joseph Fourier, Grenoble, France
| | - Chung Ming Tse
- Gastroenterology Division, Departments of Physiology and Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Mark Donowitz
- Gastroenterology Division, Departments of Physiology and Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Chantal Rémy
- Unit 836, Institut National de la Santé et de la Recherche Médicale, La Tronche, Isère, France
- Grenoble Institut des Neurosciences, Université Joseph Fourier, Grenoble, France
| | - Jonathan A. Coles
- Unit 836, Institut National de la Santé et de la Recherche Médicale, La Tronche, Isère, France
- Grenoble Institut des Neurosciences, Université Joseph Fourier, Grenoble, France
- Centre for Biophotonics, University of Strathclyde, Glasgow, United Kingdom
- * E-mail:
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