1
|
Penet MF, Sharma RK, Bharti S, Mori N, Artemov D, Bhujwalla ZM. Cancer insights from magnetic resonance spectroscopy of cells and excised tumors. NMR IN BIOMEDICINE 2023; 36:e4724. [PMID: 35262263 PMCID: PMC9458776 DOI: 10.1002/nbm.4724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 03/03/2022] [Accepted: 03/04/2022] [Indexed: 06/14/2023]
Abstract
Multinuclear ex vivo magnetic resonance spectroscopy (MRS) of cancer cells, xenografts, human cancer tissue, and biofluids is a rapidly expanding field that is providing unique insights into cancer. Starting from the 1970s, the field has continued to evolve as a stand-alone technology or as a complement to in vivo MRS to characterize the metabolome of cancer cells, cancer-associated stromal cells, immune cells, tumors, biofluids and, more recently, changes in the metabolome of organs induced by cancers. Here, we review some of the insights into cancer obtained with ex vivo MRS and provide a perspective of future directions. Ex vivo MRS of cells and tumors provides opportunities to understand the role of metabolism in cancer immune surveillance and immunotherapy. With advances in computational capabilities, the integration of artificial intelligence to identify differences in multinuclear spectral patterns, especially in easily accessible biofluids, is providing exciting advances in detection and monitoring response to treatment. Metabolotheranostics to target cancers and to normalize metabolic changes in organs induced by cancers to prevent cancer-induced morbidity are other areas of future development.
Collapse
Affiliation(s)
- Marie-France Penet
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, Maryland, USA
- Sidney Kimmel Comprehensive Cancer Center, Baltimore, Maryland, USA
| | - Raj Kumar Sharma
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, Maryland, USA
| | - Santosh Bharti
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, Maryland, USA
| | - Noriko Mori
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, Maryland, USA
| | - Dmitri Artemov
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, Maryland, USA
- Sidney Kimmel Comprehensive Cancer Center, Baltimore, Maryland, USA
| | - Zaver M. Bhujwalla
- Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, Maryland, USA
- Sidney Kimmel Comprehensive Cancer Center, Baltimore, Maryland, USA
- Department of Radiation Oncology and Molecular Radiation Sciences, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| |
Collapse
|
2
|
Theillet FX, Luchinat E. In-cell NMR: Why and how? PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2022; 132-133:1-112. [PMID: 36496255 DOI: 10.1016/j.pnmrs.2022.04.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 04/19/2022] [Accepted: 04/27/2022] [Indexed: 06/17/2023]
Abstract
NMR spectroscopy has been applied to cells and tissues analysis since its beginnings, as early as 1950. We have attempted to gather here in a didactic fashion the broad diversity of data and ideas that emerged from NMR investigations on living cells. Covering a large proportion of the periodic table, NMR spectroscopy permits scrutiny of a great variety of atomic nuclei in all living organisms non-invasively. It has thus provided quantitative information on cellular atoms and their chemical environment, dynamics, or interactions. We will show that NMR studies have generated valuable knowledge on a vast array of cellular molecules and events, from water, salts, metabolites, cell walls, proteins, nucleic acids, drugs and drug targets, to pH, redox equilibria and chemical reactions. The characterization of such a multitude of objects at the atomic scale has thus shaped our mental representation of cellular life at multiple levels, together with major techniques like mass-spectrometry or microscopies. NMR studies on cells has accompanied the developments of MRI and metabolomics, and various subfields have flourished, coined with appealing names: fluxomics, foodomics, MRI and MRS (i.e. imaging and localized spectroscopy of living tissues, respectively), whole-cell NMR, on-cell ligand-based NMR, systems NMR, cellular structural biology, in-cell NMR… All these have not grown separately, but rather by reinforcing each other like a braided trunk. Hence, we try here to provide an analytical account of a large ensemble of intricately linked approaches, whose integration has been and will be key to their success. We present extensive overviews, firstly on the various types of information provided by NMR in a cellular environment (the "why", oriented towards a broad readership), and secondly on the employed NMR techniques and setups (the "how", where we discuss the past, current and future methods). Each subsection is constructed as a historical anthology, showing how the intrinsic properties of NMR spectroscopy and its developments structured the accessible knowledge on cellular phenomena. Using this systematic approach, we sought i) to make this review accessible to the broadest audience and ii) to highlight some early techniques that may find renewed interest. Finally, we present a brief discussion on what may be potential and desirable developments in the context of integrative studies in biology.
Collapse
Affiliation(s)
- Francois-Xavier Theillet
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France.
| | - Enrico Luchinat
- Dipartimento di Scienze e Tecnologie Agro-Alimentari, Alma Mater Studiorum - Università di Bologna, Piazza Goidanich 60, 47521 Cesena, Italy; CERM - Magnetic Resonance Center, and Neurofarba Department, Università degli Studi di Firenze, 50019 Sesto Fiorentino, Italy
| |
Collapse
|
3
|
Magnetic Resonance Imaging (MRI) and MR Spectroscopic Methods in Understanding Breast Cancer Biology and Metabolism. Metabolites 2022; 12:metabo12040295. [PMID: 35448482 PMCID: PMC9030399 DOI: 10.3390/metabo12040295] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Revised: 03/22/2022] [Accepted: 03/23/2022] [Indexed: 02/01/2023] Open
Abstract
A common malignancy that affects women is breast cancer. It is the second leading cause of cancer-related death among women. Metabolic reprogramming occurs during cancer growth, invasion, and metastases. Functional magnetic resonance (MR) methods comprising an array of techniques have shown potential for illustrating physiological and molecular processes changes before anatomical manifestations on conventional MR imaging. Among these, in vivo proton (1H) MR spectroscopy (MRS) is widely used for differentiating breast malignancy from benign diseases by measuring elevated choline-containing compounds. Further, the use of hyperpolarized 13C and 31P MRS enhanced the understanding of glucose and phospholipid metabolism. The metabolic profiling of an array of biological specimens (intact tissues, tissue extracts, and various biofluids such as blood, urine, nipple aspirates, and fine needle aspirates) can also be investigated through in vitro high-resolution NMR spectroscopy and high-resolution magic angle spectroscopy (HRMAS). Such studies can provide information on more metabolites than what is seen by in vivo MRS, thus providing a deeper insight into cancer biology and metabolism. The analysis of a large number of NMR spectral data sets through multivariate statistical methods classified the tumor sub-types. It showed enormous potential in the development of new therapeutic approaches. Recently, multiparametric MRI approaches were found to be helpful in elucidating the pathophysiology of cancer by quantifying structural, vasculature, diffusion, perfusion, and metabolic abnormalities in vivo. This review focuses on the applications of NMR, MRS, and MRI methods in understanding breast cancer biology and in the diagnosis and therapeutic monitoring of breast cancer.
Collapse
|
4
|
Salzillo TC, Mawoneke V, Weygand J, Shetty A, Gumin J, Zacharias NM, Gammon ST, Piwnica-Worms D, Fuller GN, Logothetis CJ, Lang FF, Bhattacharya PK. Measuring the Metabolic Evolution of Glioblastoma throughout Tumor Development, Regression, and Recurrence with Hyperpolarized Magnetic Resonance. Cells 2021; 10:cells10102621. [PMID: 34685601 PMCID: PMC8534002 DOI: 10.3390/cells10102621] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Revised: 09/20/2021] [Accepted: 09/23/2021] [Indexed: 12/23/2022] Open
Abstract
Rapid diagnosis and therapeutic monitoring of aggressive diseases such as glioblastoma can improve patient survival by providing physicians the time to optimally deliver treatment. This research tested whether metabolic imaging with hyperpolarized MRI could detect changes in tumor progression faster than conventional anatomic MRI in patient-derived glioblastoma murine models. To capture the dynamic nature of cancer metabolism, hyperpolarized MRI, NMR spectroscopy, and immunohistochemistry were performed at several time-points during tumor development, regression, and recurrence. Hyperpolarized MRI detected significant changes of metabolism throughout tumor progression whereas conventional MRI was less sensitive. This was accompanied by aberrations in amino acid and phospholipid lipid metabolism and MCT1 expression. Hyperpolarized MRI can help address clinical challenges such as identifying malignant disease prior to aggressive growth, differentiating pseudoprogression from true progression, and predicting relapse. The individual evolution of these metabolic assays as well as their correlations with one another provides context for further academic research.
Collapse
Affiliation(s)
- Travis C. Salzillo
- Department of Cancer Systems Imaging, The University of Texas MD Anderson Cancer Center, Houston, TX 77054, USA; (T.C.S.); (V.M.); (A.S.); (S.T.G.); (D.P.-W.)
| | - Vimbai Mawoneke
- Department of Cancer Systems Imaging, The University of Texas MD Anderson Cancer Center, Houston, TX 77054, USA; (T.C.S.); (V.M.); (A.S.); (S.T.G.); (D.P.-W.)
| | - Joseph Weygand
- Department of Radiation Oncology, Moffitt Cancer Center, Tampa, FL 33612, USA;
| | - Akaanksh Shetty
- Department of Cancer Systems Imaging, The University of Texas MD Anderson Cancer Center, Houston, TX 77054, USA; (T.C.S.); (V.M.); (A.S.); (S.T.G.); (D.P.-W.)
| | - Joy Gumin
- Department of Neurosurgery, The University of Texas MD Anderson Cancer Center, Houston, TX 77054, USA; (J.G.); (F.F.L.)
| | - Niki M. Zacharias
- Department of Urology, The University of Texas MD Anderson Cancer Center, Houston, TX 77054, USA;
| | - Seth T. Gammon
- Department of Cancer Systems Imaging, The University of Texas MD Anderson Cancer Center, Houston, TX 77054, USA; (T.C.S.); (V.M.); (A.S.); (S.T.G.); (D.P.-W.)
| | - David Piwnica-Worms
- Department of Cancer Systems Imaging, The University of Texas MD Anderson Cancer Center, Houston, TX 77054, USA; (T.C.S.); (V.M.); (A.S.); (S.T.G.); (D.P.-W.)
| | - Gregory N. Fuller
- Department of Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX 77054, USA;
| | - Christopher J. Logothetis
- Department of Genitourinary Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77054, USA;
| | - Frederick F. Lang
- Department of Neurosurgery, The University of Texas MD Anderson Cancer Center, Houston, TX 77054, USA; (J.G.); (F.F.L.)
| | - Pratip K. Bhattacharya
- Department of Cancer Systems Imaging, The University of Texas MD Anderson Cancer Center, Houston, TX 77054, USA; (T.C.S.); (V.M.); (A.S.); (S.T.G.); (D.P.-W.)
- Correspondence: ; Tel.: +1-713-454-9887
| |
Collapse
|
5
|
Masalha W, Daka K, Woerner J, Pompe N, Weber S, Delev D, Krüger MT, Schnell O, Beck J, Heiland DH, Grauvogel J. Metabolic alterations in meningioma reflect the clinical course. BMC Cancer 2021; 21:211. [PMID: 33648471 PMCID: PMC7923818 DOI: 10.1186/s12885-021-07887-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Accepted: 02/08/2021] [Indexed: 11/10/2022] Open
Abstract
Background Meningiomas are common brain tumours that are usually defined by benign clinical course. However, some meningiomas undergo a malignant transformation and recur within a short time period regardless of their World Health Organization (WHO) grade. The current study aimed to identify potential markers that can discriminate between benign and malignant meningioma courses. Methods We profiled the metabolites from 43 patients with low- and high-grade meningiomas. Tumour specimens were analyzed by nuclear magnetic resonance analysis; 270 metabolites were identified and clustered with the AutoPipe algorithm. Results We observed two distinct clusters marked by alterations in glycine/serine and choline/tryptophan metabolism. Glycine/serine cluster showed significantly lower WHO grades and proliferation rates. Also progression-free survival was significantly longer in the glycine/serine cluster. Conclusion Our findings suggest that alterations in glycine/serine metabolism are associated with lower proliferation and more recurrent tumours. Altered choline/tryptophan metabolism was associated with increases proliferation, and recurrence. Our results suggest that tumour malignancy can be reflected by metabolic alterations, which may support histological classifications to predict the clinical outcome of patients with meningiomas. Supplementary Information The online version contains supplementary material available at 10.1186/s12885-021-07887-5.
Collapse
Affiliation(s)
- Waseem Masalha
- Department of Neurosurgery, University Medical Center Freiburg, Breisacher Straße 64, 79106, Freiburg, Germany. .,Faculty of Medicine, University of Freiburg, Freiburg im Breisgau, Germany.
| | - Karam Daka
- Department of Neurosurgery, University Medical Center Freiburg, Breisacher Straße 64, 79106, Freiburg, Germany.,Faculty of Medicine, University of Freiburg, Freiburg im Breisgau, Germany
| | - Jakob Woerner
- Institute of Physical Chemistry, Faculty of Chemistry and Pharmacy, University of Freiburg, Freiburg im Breisgau, Germany
| | - Nils Pompe
- Institute of Physical Chemistry, Faculty of Chemistry and Pharmacy, University of Freiburg, Freiburg im Breisgau, Germany
| | - Stefan Weber
- Institute of Physical Chemistry, Faculty of Chemistry and Pharmacy, University of Freiburg, Freiburg im Breisgau, Germany
| | - Daniel Delev
- Department of Neurosurgery, RWTH University, Aachen, Germany
| | - Marie T Krüger
- Department of Neurosurgery, Cantonal Hospital St.Gallen, st. gallen, Switzerland
| | - Oliver Schnell
- Department of Neurosurgery, University Medical Center Freiburg, Breisacher Straße 64, 79106, Freiburg, Germany.,Faculty of Medicine, University of Freiburg, Freiburg im Breisgau, Germany
| | - Jürgen Beck
- Department of Neurosurgery, University Medical Center Freiburg, Breisacher Straße 64, 79106, Freiburg, Germany.,Faculty of Medicine, University of Freiburg, Freiburg im Breisgau, Germany
| | - Dieter Henrik Heiland
- Department of Neurosurgery, University Medical Center Freiburg, Breisacher Straße 64, 79106, Freiburg, Germany.,Faculty of Medicine, University of Freiburg, Freiburg im Breisgau, Germany
| | - Juergen Grauvogel
- Department of Neurosurgery, University Medical Center Freiburg, Breisacher Straße 64, 79106, Freiburg, Germany.,Faculty of Medicine, University of Freiburg, Freiburg im Breisgau, Germany
| |
Collapse
|
6
|
Švec P, Nový Z, Kučka J, Petřík M, Sedláček O, Kuchař M, Lišková B, Medvedíková M, Kolouchová K, Groborz O, Loukotová L, Konefał RŁ, Hajdúch M, Hrubý M. Iodinated Choline Transport-Targeted Tracers. J Med Chem 2020; 63:15960-15978. [PMID: 33271015 DOI: 10.1021/acs.jmedchem.0c01710] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We present a novel series of radioiodinated tracers and potential theranostics for diseases accompanied by pathological function of proteins involved in choline transport. Unlike choline analogues labeled with 11C or 18F that are currently used in the clinic, the iodinated compounds described herein are applicable in positron emission tomography, single-photon emission computed tomography, and potentially in therapy, depending on the iodine isotope selection. Moreover, favorable half-lives of iodine isotopes result in much less challenging synthesis by isotope exchange reaction. Six of the described compounds were nanomolar ligands, and the best compound possessed an affinity 100-fold greater than that of choline. Biodistribution data of 125I-labeled ligands in human prostate carcinoma bearing (PC-3) mice revealed two compounds with a biodistribution profile superior to that of [18F]fluorocholine.
Collapse
Affiliation(s)
- Pavel Švec
- Institute of Macromolecular Chemistry, CAS, Heyrovského sq. 2, Prague 6 162 06, Czech Republic.,Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University, Hlavova 8, Prague 2 128 43, Czech Republic
| | - Zbyněk Nový
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacký University Olomouc, Hněvotínská 5, Olomouc 779 00, Czech Republic
| | - Jan Kučka
- Institute of Macromolecular Chemistry, CAS, Heyrovského sq. 2, Prague 6 162 06, Czech Republic
| | - Miloš Petřík
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacký University Olomouc, Hněvotínská 5, Olomouc 779 00, Czech Republic
| | - Ondřej Sedláček
- Institute of Macromolecular Chemistry, CAS, Heyrovského sq. 2, Prague 6 162 06, Czech Republic
| | - Martin Kuchař
- Forensic Laboratory of Biologically Active Substances, University of Chemistry and Technology, Technická 1905/5, Prague 160 00, Czech Republic
| | - Barbora Lišková
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacký University Olomouc, Hněvotínská 5, Olomouc 779 00, Czech Republic
| | - Martina Medvedíková
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacký University Olomouc, Hněvotínská 5, Olomouc 779 00, Czech Republic
| | - Kristýna Kolouchová
- Institute of Macromolecular Chemistry, CAS, Heyrovského sq. 2, Prague 6 162 06, Czech Republic
| | - Ondřej Groborz
- Institute of Macromolecular Chemistry, CAS, Heyrovského sq. 2, Prague 6 162 06, Czech Republic
| | - Lenka Loukotová
- Institute of Macromolecular Chemistry, CAS, Heyrovského sq. 2, Prague 6 162 06, Czech Republic
| | - Rafał Ł Konefał
- Institute of Macromolecular Chemistry, CAS, Heyrovského sq. 2, Prague 6 162 06, Czech Republic
| | - Marián Hajdúch
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacký University Olomouc, Hněvotínská 5, Olomouc 779 00, Czech Republic
| | - Martin Hrubý
- Institute of Macromolecular Chemistry, CAS, Heyrovského sq. 2, Prague 6 162 06, Czech Republic
| |
Collapse
|
7
|
Arlauckas SP, Kumar M, Popov AV, Poptani H, Delikatny EJ. Near infrared fluorescent imaging of choline kinase alpha expression and inhibition in breast tumors. Oncotarget 2017; 8:16518-16530. [PMID: 28157707 PMCID: PMC5369982 DOI: 10.18632/oncotarget.14965] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Accepted: 01/16/2017] [Indexed: 12/23/2022] Open
Abstract
Choline kinase alpha (ChoKα) overexpression is associated with an aggressive tumor phenotype. ChoKα inhibitors induce apoptosis in tumors, however validation of their specificity is difficult in vivo. We report the use of optical imaging to assess ChoKα status in cells and in vivo using JAS239, a carbocyanine-based ChoKα inhibitor with inherent near infrared fluorescence. JAS239 attenuated choline phosphorylation and viability in a panel of human breast cancer cell lines. Antibody blockade prevented cellular retention of JAS239 indicating direct interaction with ChoKα independent of the choline transporters and catabolic choline pathways. In mice bearing orthotopic MCF7 breast xenografts, optical imaging with JAS239 distinguished tumors overexpressing ChoKα from their empty vector counterparts and delineated tumor margins. Pharmacological inhibition of ChoK by the established inhibitor MN58b led to a growth inhibition in 4175-Luc+ tumors that was accompanied by concomitant reduction in JAS239 uptake and decreased total choline metabolite levels as measured using magnetic resonance spectroscopy. At higher therapeutic doses, JAS239 was as effective as MN58b at arresting tumor growth and inducing apoptosis in MDA-MB-231 tumors, significantly reducing tumor choline below baseline levels without observable systemic toxicity. These data introduce a new method to monitor therapeutically effective inhibitors of choline metabolism in breast cancer using a small molecule companion diagnostic.
Collapse
Affiliation(s)
- Sean P Arlauckas
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Manoj Kumar
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Anatoliy V Popov
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Harish Poptani
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States.,Department of Cellular and Molecular Physiology, Institute of Regenerative Medicine, University of Liverpool, Liverpool, United Kingdom
| | - Edward J Delikatny
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| |
Collapse
|
8
|
Arlauckas SP, Popov AV, Delikatny EJ. Choline kinase alpha-Putting the ChoK-hold on tumor metabolism. Prog Lipid Res 2016; 63:28-40. [PMID: 27073147 PMCID: PMC5360181 DOI: 10.1016/j.plipres.2016.03.005] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Revised: 03/14/2016] [Accepted: 03/26/2016] [Indexed: 12/24/2022]
Abstract
It is well established that lipid metabolism is drastically altered during tumor development and response to therapy. Choline kinase alpha (ChoKα) is a key mediator of these changes, as it represents the first committed step in the Kennedy pathway of phosphatidylcholine biosynthesis and ChoKα expression is upregulated in many human cancers. ChoKα activity is associated with drug resistant, metastatic, and malignant phenotypes, and represents a robust biomarker and therapeutic target in cancer. Effective ChoKα inhibitors have been developed and have recently entered clinical trials. ChoKα's clinical relevance was, until recently, attributed solely to its production of second messenger intermediates of phospholipid synthesis. The recent discovery of a non-catalytic scaffolding function of ChoKα may link growth receptor signaling to lipid biogenesis and requires a reinterpretation of the design and validation of ChoKα inhibitors. Advances in positron emission tomography, magnetic resonance spectroscopy, and optical imaging methods now allow for a comprehensive understanding of ChoKα expression and activity in vivo. We will review the current understanding of ChoKα metabolism, its role in tumor biology and the development and validation of targeted therapies and companion diagnostics for this important regulatory enzyme. This comes at a critical time as ChoKα-targeting programs receive more clinical interest.
Collapse
Affiliation(s)
- Sean P Arlauckas
- Department of Radiology, 317 Anatomy-Chemistry Building, 3620 Hamilton Walk, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Anatoliy V Popov
- Department of Radiology, 317 Anatomy-Chemistry Building, 3620 Hamilton Walk, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - E James Delikatny
- Department of Radiology, 317 Anatomy-Chemistry Building, 3620 Hamilton Walk, University of Pennsylvania, Philadelphia, PA 19104, USA.
| |
Collapse
|
9
|
Zarifi M, Tzika AA. Proton MRS imaging in pediatric brain tumors. Pediatr Radiol 2016; 46:952-62. [PMID: 27233788 DOI: 10.1007/s00247-016-3547-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2014] [Revised: 11/30/2015] [Accepted: 01/13/2016] [Indexed: 12/14/2022]
Abstract
Magnetic resonance (MR) techniques offer a noninvasive, non-irradiating yet sensitive approach to diagnosing and monitoring pediatric brain tumors. Proton MR spectroscopy (MRS), as an adjunct to MRI, is being more widely applied to monitor the metabolic aspects of brain cancer. In vivo MRS biomarkers represent a promising advance and may influence treatment choice at both initial diagnosis and follow-up, given the inherent difficulties of sequential biopsies to monitor therapeutic response. When combined with anatomical or other types of imaging, MRS provides unique information regarding biochemistry in inoperable brain tumors and can complement neuropathological data, guide biopsies and enhance insight into therapeutic options. The combination of noninvasively acquired prognostic information and the high-resolution anatomical imaging provided by conventional MRI is expected to surpass molecular analysis and DNA microarray gene profiling, both of which, although promising, depend on invasive biopsy. This review focuses on recent data in the field of MRS in children with brain tumors.
Collapse
Affiliation(s)
- Maria Zarifi
- Department of Radiology, Aghia Sophia Children's Hospital, Athens, Greece
| | - A Aria Tzika
- Department of Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA. .,Shriners Burn Hospital, 51 Blossom St., Room #261, Boston, MA, 02114, USA.
| |
Collapse
|
10
|
Kahlert UD, Cheng M, Koch K, Marchionni L, Fan X, Raabe EH, Maciaczyk J, Glunde K, Eberhart CG. Alterations in cellular metabolome after pharmacological inhibition of Notch in glioblastoma cells. Int J Cancer 2015; 138:1246-55. [PMID: 26422827 DOI: 10.1002/ijc.29873] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2015] [Revised: 09/04/2015] [Accepted: 09/17/2015] [Indexed: 12/18/2022]
Abstract
Notch signaling can promote tumorigenesis in the nervous system and plays important roles in stem-like cancer cells. However, little is known about how Notch inhibition might alter tumor metabolism, particularly in lesions arising in the brain. The gamma-secretase inhibitor MRK003 was used to treat glioblastoma neurospheres, and they were subdivided into sensitive and insensitive groups in terms of canonical Notch target response. Global metabolomes were then examined using proton magnetic resonance spectroscopy, and changes in intracellular concentration of various metabolites identified which correlate with Notch inhibition. Reductions in glutamate were verified by oxidation-based colorimetric assays. Interestingly, the alkylating chemotherapeutic agent temozolomide, the mTOR-inhibitor MLN0128, and the WNT inhibitor LGK974 did not reduce glutamate levels, suggesting that changes to this metabolite might reflect specific downstream effects of Notch blockade in gliomas rather than general sequelae of tumor growth inhibition. Global and targeted expression analyses revealed that multiple genes important in glutamate homeostasis, including glutaminase, are dysregulated after Notch inhibition. Treatment with an allosteric inhibitor of glutaminase, compound 968, could slow glioblastoma growth, and Notch inhibition may act at least in part by regulating glutaminase and glutamate.
Collapse
Affiliation(s)
- Ulf D Kahlert
- Department of Pathology, Division of Neuropathology, Johns Hopkins Hospital, Baltimore, MD.,Department of Neurosurgery, University Medical Center, Forschungsgebaeude Pathologie, Düsseldorf, Germany
| | - Menglin Cheng
- Division of Cancer Imaging Research, Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Hospital, Baltimore, MD
| | - Katharina Koch
- Department of Neurosurgery, University Medical Center, Forschungsgebaeude Pathologie, Düsseldorf, Germany
| | - Luigi Marchionni
- Department of Oncology, Johns Hopkins Hospital, Baltimore, MD.,Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Xing Fan
- Department of Neurosurgery, University of Michigan, Ann Arbor, MI.,Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI
| | - Eric H Raabe
- Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD.,Department of Pediatric Oncology, Johns Hopkins Hospital, Baltimore, MD
| | - Jarek Maciaczyk
- Department of Neurosurgery, University Medical Center, Forschungsgebaeude Pathologie, Düsseldorf, Germany
| | - Kristine Glunde
- Division of Cancer Imaging Research, Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Hospital, Baltimore, MD.,Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Charles G Eberhart
- Department of Pathology, Division of Neuropathology, Johns Hopkins Hospital, Baltimore, MD
| |
Collapse
|
11
|
Hurd RE, Yen YF, Chen A, Ardenkjaer-Larsen JH. Hyperpolarized 13C metabolic imaging using dissolution dynamic nuclear polarization. J Magn Reson Imaging 2013; 36:1314-28. [PMID: 23165733 DOI: 10.1002/jmri.23753] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2011] [Accepted: 06/10/2012] [Indexed: 12/18/2022] Open
Abstract
This article describes the basic physics of dissolution dynamic nuclear polarization (dissolution-DNP), and the impact of the resulting highly nonequilibrium spin states, on the physics of magnetic resonance imaging (MRI) detection. The hardware requirements for clinical translation of this technology are also presented. For studies that allow the use of externally administered agents, hyperpolarization offers a way to overcome normal magnetic resonance sensitivity limitations, at least for a brief T(1)-dependent observation window. A 10,000-100,000-fold signal-to-noise advantage provides an avenue for real-time measurement of perfusion, metabolite transport, exchange, and metabolism. The principles behind these measurements, as well as the choice of agent, and progress toward the application of hyperpolarized (13)C metabolic imaging in oncology, cardiology, and neurology are reviewed.
Collapse
|
12
|
Hattingen E, Bähr O, Rieger J, Blasel S, Steinbach J, Pilatus U. Phospholipid metabolites in recurrent glioblastoma: in vivo markers detect different tumor phenotypes before and under antiangiogenic therapy. PLoS One 2013; 8:e56439. [PMID: 23520454 PMCID: PMC3592858 DOI: 10.1371/journal.pone.0056439] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2012] [Accepted: 01/09/2013] [Indexed: 11/18/2022] Open
Abstract
Purpose Metabolic changes upon antiangiogenic therapy of recurrent glioblastomas (rGBMs) may provide new biomarkers for treatment efficacy. Since in vitro models showed that phospholipid membrane metabolism provides specific information on tumor growth we employed in-vivo MR-spectroscopic imaging (MRSI) of human rGBMs before and under bevacizumab (BVZ) to measure concentrations of phosphocholine (PCho), phosphoethanolamine (PEth), glycerophosphocholine (GPC), and glyceroethanolamine (GPE). Methods 1H and 31P MRSI was prospectively performed in 32 patients with rGBMs before and under BVZ therapy at 8 weeks intervals until tumor progression. Patients were dichotomized into subjects with long overall survival (OS) (>median OS) and short OS (<median OS) survival time from BVZ-onset. Metabolite concentrations from tumor tissue and their ratios were compared to contralateral normal-appearing tissue (control). Results Before BVZ, 1H-detectable choline signals (total GPC and PCho) in rGBMs were elevated but significance failed after dichotomizing. For metabolite ratios obtained by 31P MRSI, the short-OS group showed higher PCho/GPC (p = 0.004) in rGBMs compared to control tissue before BVZ while PEth/GPE was elevated in rGBMs of both groups (long-OS p = 0.04; short-OS p = 0.003). Under BVZ, PCho/GPC and PEth/GPE in the tumor initially decreased (p = 0.04) but only PCho/GPC re-increased upon tumor progression (p = 0.02). Intriguingly, in normal-appearing tissue an initial PEth/GPE decrease (p = 0.047) was followed by an increase at the time of tumor progression (p = 0.031). Conclusion An elevated PCho/GPC ratio in the short-OS group suggests that it is a negative predictive marker for BVZ efficacy. These gliomas may represent a malignant phenotype even growing under anti-VEGF treatment. Elevated PEth/GPE may represent an in-vivo biomarker more sensitive to GBM infiltration than MRI.
Collapse
Affiliation(s)
- Elke Hattingen
- Institute of Neuroradiology, Goethe-University Hospital Frankfurt, Frankfurt, Germany.
| | | | | | | | | | | |
Collapse
|
13
|
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.
Collapse
Affiliation(s)
- Dominick J O McIntyre
- Cancer Research UK, Cambridge Research Institute, Li Ka Shing Centre, Robinson Way, Cambridge CB2 0RE, UK.
| | | | | | | |
Collapse
|
14
|
Wagner M, Nafe R, Jurcoane A, Pilatus U, Franz K, Rieger J, Steinbach JP, Hattingen E. Heterogeneity in malignant gliomas: a magnetic resonance analysis of spatial distribution of metabolite changes and regional blood volume. J Neurooncol 2011; 103:663-72. [PMID: 21061143 DOI: 10.1007/s11060-010-0443-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2010] [Accepted: 10/21/2010] [Indexed: 11/28/2022]
Abstract
First-pass contrast-enhanced dynamic perfusion imaging provides information about the regional cerebral blood volume (rCBV), an increase of which indicates neovascularization. MR spectroscopic imaging informs about metabolite changes in brain tumors, with elevated choline (Cho) values revealing cell proliferation and density, and the glial metabolite creatine (Cr) representing high-energy storage. This study investigates metabolite changes within the tumor voxel of maximal rCBV value (rCBVmax). Anatomically coregistered parameter maps of rCBV, Cho and Cr were evaluated in 36 patients with primary or recurrent WHO grade III or IV gliomas. Apart from Cho and Cr values within the voxel of rCBVmax (Choperf, Crperf), the maximal Cho and Cr values of the tumor tissue were recorded (Chomax, Crmax). The correlation between these parameters was analyzed with Spearman’s rho test while a binomial test was performed to check whether Chomax = Choperf and Crmax = Crperf. We found that, in 29 of the 36 patients, neither Cho nor Cr had their maxima in the voxel of rCBVmax (Choperf, Crperf < Chomax, Crmax, P < 0.001). However, Choperf was highly correlated with Chomax (r = 0.76, P < 0.001) and Crperf with Crmax (r = 0.47, P < 0.001). Further Choperf correlated with Crperf (r = 0.55, P < 0.001). Neither of the spectroscopic parameters (Chomax, Crmax, Choperf, Crperf,) correlated with rCBVmax. In conclusion, in WHO grade III and IV gliomas the voxel with maximal rCBV often differs from the voxel with the maximal Cho and Cr, indicating the spatial divergence between neovascularization and tumor cell proliferation, cell density and glial processes. However, tCho and tCr changes within the area of neovascularization are positively correlated with the maximal increase within the tumor tissue. These results demonstrate aspects of regional tumor heterogeneity as characterized by different MR modalities that, apart from histopathological grading might be crucial for neurosurgical biopsy as well as for antiangiogenetic and future molecular therapies.
Collapse
Affiliation(s)
- Marlies Wagner
- Institute of Neuroradiology, Goethe University, Frankfurt am Main, Germany
| | | | | | | | | | | | | | | |
Collapse
|
15
|
Batra V, Kislay B, Devasagayam TPA. Interaction between total body gamma-irradiation and choline deficiency triggers immediate modulation of choline and choline-containing moieties. Int J Radiat Biol 2011; 87:1196-207. [PMID: 21923302 DOI: 10.3109/09553002.2011.624153] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
PURPOSE The objective of this study was to examine the effect of 60Co-gamma (γ) radiation on acute phase modulation, if any, of choline and choline-containing moieties in choline-deficient subjects. Corresponding results could provide information that might be useful in the management of adverse effects of γ-radiation. MATERIALS AND METHODS Male Swiss mice maintained on a choline-sufficient diet (CSD) and choline-free diet (CFD) based on AIN-93M formula, were subjected to whole body γ-irradiation (2-6 Gy). Liver, serum and brain samples from each group were then tested for: (i) Alterations in choline and choline-containing moieties such as phosphatidylcholine (PC) and sphingomyeline (SM); and (ii) modulation of choline profile modulating enzymes such as phospholipase D (PLD) and total sphingomyelinase (t-SMase). Liver and brain samples were also subjected to histo-pathological examinations. RESULTS No significant changes were observed in folate, choline, choline-containing moieties and choline-modulating enzymes in choline-sufficient mice. In contrast, interaction between cytotoxic effects of γ-radiation and choline deficiency modulated choline and choline-containing moieties. Feeding CFD reduced hepatic concentrations of choline, PC and SM whereas PLD and t-SMase activities were significantly raised. The decrease in liver choline and choline-containing moieties was accompanied by an increase in blood choline concentration. Despite choline deficiency, the level of choline and acetylcholine synthesizing enzyme choline acetyltransfease (ChAT) significantly increased in the brain. CONCLUSIONS We propose that choline deprivation and γ-radiation interact to modulate choline reserves of hepatic tissue, which might release choline to blood. Our studies also clearly showed that interaction between choline deficiency and γ-radiation might substantially enhance liver adipogenesis.
Collapse
Affiliation(s)
- Vipen Batra
- Radiation Biology and Health Sciences Division, Bhabha Atomic Research Centre, Mumbai, India.
| | | | | |
Collapse
|
16
|
Hattingen E, Jurcoane A, Bähr O, Rieger J, Magerkurth J, Anti S, Steinbach JP, Pilatus U. Bevacizumab impairs oxidative energy metabolism and shows antitumoral effects in recurrent glioblastomas: a 31P/1H MRSI and quantitative magnetic resonance imaging study. Neuro Oncol 2011; 13:1349-63. [PMID: 21890539 DOI: 10.1093/neuonc/nor132] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Bevacizumab shows unprecedented rates of response in recurrent glioblastomas (GBM), but the detailed mechanisms are still unclear. We employed in vivo magnetic resonance spectroscopic imaging (MRSI) and quantitative magnetic resonance imaging to investigate whether bevacizumab alters oxygen and energy metabolism and whether this effect has antitumoral activity in recurrent GBM. (31)P and (1)H MRSI, apparent diffusion coefficient (ADC), and high-resolution T2 and T2' mapping (indirect marker of oxygen extraction) were investigated in 16 patients with recurrent GBM at 3 Tesla before and 1.5-2 months after initiation of therapy with bevacizumab. Changes of metabolite concentrations and of the quantitative values in the tumor and normal appearing brain tissue were calculated. The Wilcoxon signed-ranks test was used to evaluate differences for tumor/edema versus control as well as changes before versus after commencement of therapy. Survival analyses were performed for significant parameters. Tumor T2', pH, ADC, and T2 decreased significantly in patients responding to bevacizumab therapy (n = 10). Patients with at least 25% T2' decrease during treatment showed longer progression-free and overall survival durations. Levels of high-energy metabolites were lower at baseline; these persisted under therapy. Glycerophosphoethanolamine as catabolic phospholipid metabolite increased in responders. The MRSI data support the hypothesis that bevacizumab induces relative tumor hypoxia (T2' decrease) and affects energy homeostasis in recurrent GBM, suggesting that bevacizumab impairs vascular function. The antiangiogenic effect of bevacizumab is predictive of better outcome and seems to induce antitumoral activity in the responding GBMs.
Collapse
Affiliation(s)
- Elke Hattingen
- Goethe University Frankfurt, Institute of Neuroradiology, Schleusenweg 2-16 (Haus 95), 60528 Frankfurt/M, Germany.
| | | | | | | | | | | | | | | |
Collapse
|
17
|
Glunde K, Jiang L, Moestue SA, Gribbestad IS. MRS and MRSI guidance in molecular medicine: targeting and monitoring of choline and glucose metabolism in cancer. NMR IN BIOMEDICINE 2011; 24:673-90. [PMID: 21793073 PMCID: PMC3146026 DOI: 10.1002/nbm.1751] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
MRS and MRSI are valuable tools for the detection of metabolic changes in tumors. The currently emerging era of molecular medicine, which is shaped by molecularly targeted anticancer therapies combined with molecular imaging of the effects of such therapies, requires powerful imaging technologies that are able to detect molecular information. MRS and MRSI are such technologies that are able to detect metabolites arising from glucose and choline metabolism in noninvasive in vivo settings and at higher resolution in tissue samples. The roles played by MRS and MRSI in the diagnosis of different types of cancer, as well as in the early monitoring of the tumor response to traditional chemotherapies, are reviewed. The emerging roles of MRS and MRSI in the development and detection of novel targeted anticancer therapies that target oncogenic signaling pathways or markers in choline or glucose metabolism are discussed.
Collapse
Affiliation(s)
- Kristine Glunde
- Johns Hopkins University In Vivo Cellular and Molecular Imaging Center, Russell H. Morgan, Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Lu Jiang
- Johns Hopkins University In Vivo Cellular and Molecular Imaging Center, Russell H. Morgan, Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Siver A. Moestue
- Department of Circulation and Medical Imaging, Norwegian University of Science and Technology (NTNU), 7491 Trondheim, Norway
| | - Ingrid S. Gribbestad
- Department of Circulation and Medical Imaging, Norwegian University of Science and Technology (NTNU), 7491 Trondheim, Norway
| |
Collapse
|
18
|
Porto L, Kieslich M, Franz K, Lehrnbecher T, Zanella F, Pilatus U, Hattingen E. MR spectroscopy differentiation between high and low grade astrocytomas: a comparison between paediatric and adult tumours. Eur J Paediatr Neurol 2011; 15:214-21. [PMID: 21145271 DOI: 10.1016/j.ejpn.2010.11.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2010] [Revised: 10/21/2010] [Accepted: 11/13/2010] [Indexed: 11/19/2022]
Abstract
OBJECTIVE To investigate whether pathologically similar astrocytomas in adults and children may also show metabolic similarities in proton magnetic resonance spectroscopy ((1)H-MRS) and whether the MRS data could help to differentiate between low and high grade gliomas for the different groups. MATERIAL AND METHODS Twelve children (5 WHO II astrocytomas, 7 WHO III astrocytomas) and 37 adults (21 WHO II astrocytomas, 16 WHO III astrocytomas) were included in this study. MR spectroscopic data were evaluated retrospectively using normalized measures of total choline (tCho), N-acetyl-aspartate (NAA) and total creatine (tCr). These metabolites were used to differentiate between WHO II and WHO III astrocytomas in children and adults. Histopathological grading was performed using WHO criteria. (1)H-MRS was carried out prior to the commencement of any treatment. Signal intensities of tCho, NAA and tCr were normalized to their values in contralateral brain tissue. The resulting concentration ratios were then used to calculate the change in the intratumoural ratio of NAA to tCho. A Mann-Whitney U-Test was performed to evaluate differences within the respective groups. RESULTS In both groups, loss of NAA and increase of tCho were more pronounced in WHO III than in WHO II astrocytoma. The best discriminator to differentiate between low and high grade gliomas was found to be the ratio of NAA/tCho (p < 0.01). CONCLUSION The normalized metabolite signal intensities ratio NAA to tCho is the most accurate in differentiating between low and high grade astrocytomas in both children and adults.
Collapse
Affiliation(s)
- Luciana Porto
- Neuroradiology Department of the Johann Wolfgang Goethe University, Frankfurt/Main, Germany.
| | | | | | | | | | | | | |
Collapse
|
19
|
Moestue SA, Engebraaten O, Gribbestad IS. Metabolic effects of signal transduction inhibition in cancer assessed by magnetic resonance spectroscopy. Mol Oncol 2011; 5:224-41. [PMID: 21536506 DOI: 10.1016/j.molonc.2011.04.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2011] [Revised: 04/13/2011] [Accepted: 04/14/2011] [Indexed: 12/31/2022] Open
Abstract
Despite huge efforts in development of drugs targeting oncogenic signalling, the number of such drugs entering clinical practice to date remains limited. Rational use of biomarkers for drug candidate selection and early monitoring of response to therapy may accelerate this process. Magnetic resonance spectroscopy (MRS) can be used to assess metabolic effects of drug treatment both in vivo and in vitro, and technological advances are continuously increasing the utility of this non-invasive method. In this review, we summarise the use of MRS for monitoring the effect of targeted anticancer drugs, and discuss the potential role of MRS in the context of personalised cancer treatment.
Collapse
Affiliation(s)
- Siver Andreas Moestue
- Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway.
| | | | | |
Collapse
|
20
|
Quintero M, Cabañas ME, Arús C. 13C-labelling studies indicate compartmentalized synthesis of triacylglycerols in C6 rat glioma cells. Biochim Biophys Acta Mol Cell Biol Lipids 2010; 1801:693-701. [PMID: 20380892 DOI: 10.1016/j.bbalip.2010.03.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2009] [Revised: 03/08/2010] [Accepted: 03/23/2010] [Indexed: 12/27/2022]
Abstract
NMR-visible mobile lipid (ML) signals have been detected in (1)H-NMR spectra of tissues in vivo, ex vivo and in vitro, and have been shown to change in apparent intensity in association with pathology (necrosis in brain tumours) and normal processes (cell differentiation, cell growth arrest and apoptosis). Although it is widely accepted that ML signals originate mainly from fatty-acyl chains in triacylglycerols (TAG) contained in cytosolic lipid droplets (LD), the dynamics of TAG in LD is not yet fully understood. In order to better understand the synthesis of cellular TAG and its relationship to ML dynamics we carried out a set of labelling experiments with C6 rat glioma cells in culture. TAG and phospholipid metabolism was monitored by incubating C6 cells with [1-(13)C]-glucose at two time points during cell growth curve -24 h incubation starting at log-phase; 48 h incubation starting at saturation density- and by acquiring the 2D-HMQC NMR spectra of the respective total lipid extracts. The resulting TAG, diacylglycerol (DAG) and phospholipid labelling patterns can only be explained if TAG synthesis takes place in two different subcellular compartments. One compartment would be the endoplasmic reticulum, which is known to be involved in TAG metabolism, while the other compartment could be the plasma membrane and/or the LD. This possible role of LD is further supported by the recent description of diacylglycerolacyltranferase-activity associated with LD. Accordingly, we postulate the existence of a carbon-shuttling mechanism between plasma membrane phospholipids and endoplasmic reticulum by way of LD content. The results we have obtained with C6 cells may also apply to other cellular systems and should be taken into account when interpreting ML dynamics detected by NMR in vivo.
Collapse
Affiliation(s)
- MariaRosa Quintero
- GABRMN, Departament de Bioquímica i Biologia Molecular, Facultat de Biociències, Universitat Autònoma de Barcelona, Campus de Bellaterra, 08193 Cerdanyola del Vallès, Spain
| | | | | |
Collapse
|
21
|
Sarkar R, Comment A, Vasos PR, Jannin S, Gruetter R, Bodenhausen G, Hall H, Kirik D, Denisov VP. Proton NMR of (15)N-choline metabolites enhanced by dynamic nuclear polarization. J Am Chem Soc 2010; 131:16014-5. [PMID: 19848401 DOI: 10.1021/ja9021304] [Citation(s) in RCA: 98] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Chemical shifts of protons can report on metabolic transformations such as the conversion of choline to phosphocholine. To follow such processes in vivo, magnetization can be enhanced by dynamic nuclear polarization (DNP). We have hyperpolarized in this manner nitrogen-15 spins in (15)N-labeled choline up to 3.3% by irradiating the 94 GHz electron spin resonance of admixed TEMPO nitroxide radicals in a magnetic field of 3.35 T during ca. 3 h at 1.2 K. The sample was subsequently transferred to a high-resolution magnet, and the enhanced polarization was converted from (15)N to methyl- and methylene protons, using the small (2,3)J((1)H,(15)N) couplings in choline. The room-temperature lifetime of nitrogen polarization in choline, T(1)((15)N) approximately 200 s, could be considerably increased by partial deuteration of the molecule. This procedure enables studies of choline metabolites in vitro and in vivo using DNP-enhanced proton NMR.
Collapse
Affiliation(s)
- Riddhiman Sarkar
- Laboratory for Biomolecular Magnetic Resonance, Ecole Polytechnique Federale de Lausanne, CH-1015 Lausanne, Switzerland
| | | | | | | | | | | | | | | | | |
Collapse
|
22
|
Hattingen E, Raab P, Franz K, Lanfermann H, Setzer M, Gerlach R, Zanella FE, Pilatus U. Prognostic value of choline and creatine in WHO grade II gliomas. Neuroradiology 2008; 50:759-67. [DOI: 10.1007/s00234-008-0409-3] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2008] [Accepted: 04/30/2008] [Indexed: 11/29/2022]
|
23
|
Pfisterer WK, Hendricks WP, Scheck AC, Nieman RA, Birkner TH, Krampla WW, Preul MC. FLUORESCENT IN SITU HYBRIDIZATION AND EX VIVO 1H MAGNETIC RESONANCE SPECTROSCOPIC EXAMINATIONS OF MENINGIOMA TUMOR TISSUE. Neurosurgery 2007; 61:1048-59; discussion 1060-1. [DOI: 10.1227/01.neu.0000303201.62123.5c] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Affiliation(s)
- Wolfgang K. Pfisterer
- Neurosurgery and Neuro-Oncology Research, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona, and Neurosurgical Department, Sozialmedizinisches Zentrum-Ost, Donauspital, Vienna, Austria
| | - William P. Hendricks
- Neurosurgery and Neuro-Oncology Research, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona
| | - Adrienne C. Scheck
- Neuro-Oncology and Neurosurgery Research, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona
| | - Ronald A. Nieman
- Nuclear Magnetic Resonance Core Facility, Department of Chemistry and Biochemistry, Arizona State University, Tempe, Arizona
| | - Thomas H. Birkner
- Pathology Department, Sozialmedizinisches Zentrum-Ost, Donauspital, Vienna, Austria
| | - Wolfgang W. Krampla
- Radiology Department, Sozialmedizinisches Zentrum-Ost, Donauspital, Vienna, Austria
| | - Mark C. Preul
- Neurosurgery Research Laboratory, Division of Neurological Surgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona
| |
Collapse
|
24
|
Zheng QH, Gao M, Mock BH, Wang S, Hara T, Nazih R, Miller MA, Receveur TJ, Lopshire JC, Groh WJ, Zipes DP, Hutchins GD, DeGrado TR. Synthesis and biodistribution of new radiolabeled high-affinity choline transporter inhibitors [11C]hemicholinium-3 and [18F]hemicholinium-3. Bioorg Med Chem Lett 2007; 17:2220-4. [PMID: 17303422 DOI: 10.1016/j.bmcl.2007.01.105] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2006] [Revised: 01/21/2007] [Accepted: 01/22/2007] [Indexed: 11/22/2022]
Abstract
The high-affinity choline transporter (CHT1) system is an attractive target for the development of positron emission tomography (PET) biomarkers to probe brain, cardiac, and cancer diseases. An efficient and convenient synthesis of new radiolabeled CHT1 inhibitors [(11)C]hemicholinium-3 and [(18)F]hemicholinium-3 by solid-phase extraction (SPE) technique using a cation-exchange CM Sep-Pak cartridge has been well developed. The preliminary evaluation of both tracers through biodistribution studies in 9L-glioma rats has been performed, and the uptakes in the heart and tumor were observed, while very low brain uptake was seen.
Collapse
Affiliation(s)
- Qi-Huang Zheng
- Department of Radiology, Indiana University School of Medicine, Indianapolis, IN 46202, USA.
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
25
|
Hara T, Bansal A, DeGrado TR. Choline Transporter as a Novel Target for Molecular Imaging of Cancer. Mol Imaging 2006. [DOI: 10.2310/7290.2006.00032] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Toshihiko Hara
- From the Department of Radiology, Indiana University School of Medicine, Indianapolis, IN
| | - Aditya Bansal
- From the Department of Radiology, Indiana University School of Medicine, Indianapolis, IN
| | - Timothy R. DeGrado
- From the Department of Radiology, Indiana University School of Medicine, Indianapolis, IN
| |
Collapse
|
26
|
Valverde D, Quintero MR, Candiota AP, Badiella L, Cabañas ME, Arús C. Analysis of the changes in the 1H NMR spectral pattern of perchloric acid extracts of C6 cells with growth. NMR IN BIOMEDICINE 2006; 19:223-30. [PMID: 16485320 DOI: 10.1002/nbm.1024] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
The aim of this work was to identify spectral markers of cell proliferation that could be of use in clinical MRS. Cultured C6 ATCC rat glioma cells were used as models for this purpose and metabolites were extracted with perchloric acid at three different growth curve stages: log, confluence and post-confluence. 1D and 2D in vitro(1)H NMR spectra were recorded at 9.4 T. Statistically significant changes in myo-inositol and glutamine concentrations between log phase and post-confluence were found when normalized to the creatine ratio. The myo-inositol/creatine ratio was 2.76 +/- 0.82 at log phase increasing to 7.43 +/- 1.34 at post-confluence, while the glutamine/creatine ratio decreased from 0.22 +/- 0.03 to 0.10 +/- 0.02. No significant differences were recorded for other metabolites investigated. The fact that both myo-inositol and glutamine are detectable by in vivo MRS at clinical fields makes their changes relevant as potential astrocytic tumour proliferation rate markers in clinical MRS.
Collapse
Affiliation(s)
- D Valverde
- Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Spain
| | | | | | | | | | | |
Collapse
|
27
|
Astrakas LG, Zurakowski D, Tzika AA, Zarifi MK, Anthony DC, De Girolami U, Tarbell NJ, Black PM. Noninvasive magnetic resonance spectroscopic imaging biomarkers to predict the clinical grade of pediatric brain tumors. Clin Cancer Res 2005; 10:8220-8. [PMID: 15623597 DOI: 10.1158/1078-0432.ccr-04-0603] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The diagnosis and therapy of childhood brain tumors, most of which are low grade, can be complicated because of their frequent adjacent location to crucial structures, which limits diagnostic biopsy. Also, although new prognostic biomarkers identified by molecular analysis or DNA microarray gene profiling are promising, they too depend on invasive biopsy. Here, we test the hypothesis that combining information from biologically important intracellular molecules (biomarkers), noninvasively obtained by proton magnetic resonance spectroscopic imaging, will increase the diagnostic accuracy in determining the clinical grade of pediatric brain tumors. We evaluate the proton magnetic resonance spectroscopic imaging exams for 66 children with brain tumors. The intracellular biomarkers for choline-containing compounds (Cho), N-acetylaspartate, total creatine, and lipids and/or lactate were measured at the highest Cho region and normalized to the surrounding healthy tissue total creatine. Neuropathological grading was done with WHO criteria. Normalized Cho and lipids and/or lactate were elevated in high-grade (n = 23) versus low-grade (n = 43) tumors, which multiple logistic regression confirmed are independent predictors of tumor grade (for Cho, odds ratio 24.8, P < 0.001; and for lipids and/or lactate, odds ratio 4.4, P < 0.001). A linear combination of normalized Cho and lipids and/or lactate that maximizes diagnostic accuracy was calculated by maximizing the area under the receiver operating characteristic curve. Proton magnetic resonance spectroscopic imaging, although not a proxy for histology, provides noninvasive, in vivo biomarkers for predicting clinical grades of pediatric brain tumors.
Collapse
Affiliation(s)
- Loukas G Astrakas
- Nuclear Magnetic Resonance Surgical Laboratory, Department of Surgery, Massachusetts General Hospital, Shriners Burns Institute, Harvard Medical School, Boston, Massachusetts 02114, USA
| | | | | | | | | | | | | | | |
Collapse
|
28
|
Abstract
Magnetic resonance spectroscopy (MRS) has been used for more than two decades to interrogate metabolite distributions in living cells and tissues. Techniques have been developed that allow multiple spectra to be obtained simultaneously with individual volume elements as small as 1 uL of tissue (i.e., 1 x 1 x 1 mm(3)). The most common modern applications of in vivo MRS use endogenous signals from (1)H, (31)P, or (23)Na. Important contributions have also been made using exogenous compounds containing (19)F, (13)C, or (17)O. MRS has been used to investigate cardiac and skeletal muscle energetics, neurobiology, and cancer. This review focuses on the latter applications, with specific reference to the measurement of tissue choline, which has proven to be a tumor biomarker that is significantly affected by anticancer therapies.
Collapse
Affiliation(s)
- Robert J Gillies
- Arizona Cancer Center, 1515 Campbell Avenue, Tucson, AZ 85724-5024, USA.
| | | |
Collapse
|
29
|
Matsumura A, Isobe T, Anno I, Takano S, Kawamura H. Correlation between choline and MIB-1 index in human gliomas. A quantitative in proton MR spectroscopy study. J Clin Neurosci 2005; 12:416-20. [PMID: 15925772 DOI: 10.1016/j.jocn.2004.08.008] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2004] [Accepted: 08/03/2004] [Indexed: 11/26/2022]
Abstract
BACKGROUND Choline (Cho) containing compounds are usually evaluated using magnetic resonance spectroscopy (MRS) by relative ratios such as Cho/N-acetylaspartate (NAA) and Cho/creatine (Cre) ratios. To clarify the significance of Cho level in gliomas, we evaluated the quantified Cho level using MRS and compared it with the proliferation activity as determined by MIB-1 immunoreactivity in the histological specimen. METHODS There were seven benign and seven malignant gliomas. MRS was obtained using a single-voxel proton regional imaging of metabolites (PRIME) sequence with three different TE for T2 compensation. Quantified Cho level was compared with the number of MIB-1 immunopositive positive cells and cell density in surgical specimens. RESULT A positive correlation was observed between Cho and MIB-1 in benign gliomas, whereas there was a trend to an inverse correlation in malignant gliomas. This inverse correlation became a positive correlation when the necrotic area of the tumor (on the T1-weighted gadolinium enhanced images) was excluded from the voxel of interest (VOI) for MRS, but this correlation did not reach statistical significance. CONCLUSIONS The quantification data clarified the behavior of Cho in malignant gliomas. The quantification method has the advantage of limiting the influence of other metabolites on Cho determination. In particular, the levels of other commonly measured metabolites, including Cre, may also be altered in glioma, making ratios between metabolites misleading. Heterogeneity in the MRS VOI should be considered when evaluating the proliferative activity of malignant glioma by MRS.
Collapse
Affiliation(s)
- Akira Matsumura
- Department of Neurosurgery, Institute of Clinical Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan.
| | | | | | | | | |
Collapse
|
30
|
Albers MJ, Krieger MD, Gonzalez-Gomez I, Gilles FH, McComb JG, Nelson MD, Blüml S. Proton-decoupled 31P MRS in untreated pediatric brain tumors. Magn Reson Med 2005; 53:22-9. [PMID: 15690498 DOI: 10.1002/mrm.20312] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Proton-decoupled (31)P and (1)H MRS was used to quantify markers of membrane synthesis and breakdown in eight pediatric patients with untreated brain tumors and in six controls. Quantitation of these compounds in vivo in humans may provide important indicators for tumor growth and malignancy, tumor classification, and provide prognostic information. The ratios of phosphoethanolamine to glycerophosphoethanolamine (PE/GPE) and phosphocholine to glycerophosphocholine (PC/GPC) were significantly higher in primitive neuroectodermal tumors (PNET) (16.30 +/- 5.73 and 2.97 +/- 0.93) when compared with controls (3.42 +/- 1.62, P < 0.0001 and 0.45 +/- 0.13, P < 0.0001) and with other tumors (3.93 +/- 3.42, P < 0.001 and 0.65 +/- 0.30, P < 0.0001). Mean PC/PE was elevated in tumors relative to controls (0.48 +/- 0.11 versus 0.24 +/- 0.05, P < 0.001), but there was no difference between PNET and other tumors. Total choline concentration determined with quantitative (1)H MRS was significantly elevated (4.78 +/- 3.33 versus 1.73 +/- 0.56 mmol/kg, P < 0.05), whereas creatine was reduced in tumors (4.89 +/- 1.83 versus 8.28 +/- 1.50 mmol/kg, P < 0.05). A quantitative comparison of total phosphorylated cholines (PC+GPC)/ATP measured with (31)P MRS and total choline measured with (1)H MRS showed that in tumors a large fraction of the choline signal (>54 +/- 36%) was not accounted for by PC and GPC. The fraction of unaccounted choline was particularly large in PNET (>78 +/- 7%). The pH of tumor tissue was higher than the pH of normal brain tissue (7.06 +/- 0.03 versus. 6.98 +/- 0.03, P < 0.001).
Collapse
Affiliation(s)
- Mark J Albers
- Department of Radiology, Childrens Hospital Los Angeles, 4650 Sunset Boulevard, Los Angeles, CA 90027, USA
| | | | | | | | | | | | | |
Collapse
|
31
|
Sharma U, Mehta A, Seenu V, Jagannathan NR. Biochemical characterization of metastatic lymph nodes of breast cancer patients by in vitro 1H magnetic resonance spectroscopy: a pilot study. Magn Reson Imaging 2004; 22:697-706. [PMID: 15172064 DOI: 10.1016/j.mri.2004.01.037] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2003] [Accepted: 01/28/2004] [Indexed: 10/26/2022]
Abstract
Using one-dimensional (1D) and two-dimensional (2D) proton nuclear magnetic resonance (NMR) methods, the perchloric acid extract of involved (n = 11) and noninvolved (n = 12) axillary lymph nodes (ALN) of breast cancer patients was investigated. Resonances from 40 metabolites such as lactate (Lac), glucose, several amino acids (alanine, lysine, glutamic acid, glutamine, etc.), nucleotides (adenosine triphosphate, guanosine triphosphate, uridine triphosphate, uridine monophosphate, etc.), membrane metabolites [glycerophosphocholine (GPC), phosphocoline (PC), phosphoethanolamine (PE), choline] were unambiguously assigned in both the involved and noninvolved ALN. The concentration of PC/GPC (p = 0.002) was significantly higher in the involved compared to noninvolved nodes. In addition, the concentration of glycolytic product Lac (p = 0.0001) was also found to be significantly higher in involved nodes. Increased concentration of membrane metabolites PC/GPC may be attributed to increased membrane synthesis in malignant cells and, therefore, suggests the presence of metastatic cells in lymph nodes. The higher concentration of Lac is indicative of the presence of malignant cells that derive energy via anaerobic glycolytic pathway. Present results demonstrate the potentials of in vitro proton NMR in detecting malignant cells in ALN and such studies may have an important bearing in determining the prognosis of breast cancer patients.
Collapse
Affiliation(s)
- Uma Sharma
- Department of Nuclear Magnetic Resonance, All India Institute of Medical Sciences, New Delhi 110 029, India
| | | | | | | |
Collapse
|
32
|
Abstract
Magnetic resonance imaging (MRI) has emerged as a powerful tool in the study of normal and abnormal brain structure, function, and biochemistry. In particular, functional MRI has come into its own as a tool to study normal and abnormal brain functions such as learning, memory, and motor learning, as well as delineation of neurogenetic cognitive phenotypes. White matter microstructure can be studied using diffusion tensor imaging, which may allow abnormal white matter to be visualized prior to abnormalities on anatomic MRI. Magnetic resonance spectroscopy, a noninvasive method to study brain biochemistry, may allow for the delineation of regional metabolic changes as a result of disease progression and/or therapeutic intervention. With MRI techniques, one can investigate the relationship between structure, function, genes, and behavior. This report discusses the research applications of MRI to the study of neurogenetic disorders of childhood.
Collapse
Affiliation(s)
- Andrea Gropman
- Departments of Pediatrics and Neurology, Georgetown University Medical Center, 3800 Reservoir Road NW, 2PHC, Washington, DC 20007, USA.
| |
Collapse
|
33
|
Pathak AP, Gimi B, Glunde K, Ackerstaff E, Artemov D, Bhujwalla ZM. Molecular and functional imaging of cancer: advances in MRI and MRS. Methods Enzymol 2004; 386:3-60. [PMID: 15120245 DOI: 10.1016/s0076-6879(04)86001-4] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- Arvind P Pathak
- Department of Radiology, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
| | | | | | | | | | | |
Collapse
|
34
|
Blüml S, Philippart M, Schiffmann R, Seymour K, Ross BD. Membrane phospholipids and high-energy metabolites in childhood ataxia with CNS hypomyelination. Neurology 2003; 61:648-54. [PMID: 12963756 DOI: 10.1212/wnl.61.5.648] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND Childhood ataxia with CNS hypomyelination (CACH) is a leukodystrophy with extreme rarefaction of white matter caused by mutations in one of the five subunits of the translation initiation factor 2B (eIF2B). METHODS Seven children with this disease and nine age-matched control subjects were studied with proton-decoupled phosphorus magnetic resonance (MR) spectroscopy. RESULTS In patients with CACH, cerebral concentrations of high-energy phosphate metabolites were abnormal. Of the metabolites involved in biosynthesis and catabolism of membrane phospholipids, glycerophosphorylethanolamine was reduced (0.24 +/- 0.18 mmol/kg brain vs 0.44 +/- 0.14; p < 0.02), and phosphorylethanolamine was increased (2.32 +/- 0.53 vs 1.53 +/- 0.22; p < 0.01), whereas the choline-containing phosphorylated metabolites were unchanged. Nucleoside triphosphate (NTP) was reduced (2.44 +/- 0.34 mmol/kg brain tissue vs 3.09 +/- 0.58; p < 0.01), phosphocreatine was elevated (4.11 +/- 0.63 vs 3.27 +/- 0.33; p < 0.01), and inorganic phosphate was reduced (0.77 +/- 0.32 vs 1.06 +/- 0.26; p < 0.05). Intracellular pH was elevated in patients (7.03 +/- 0.04 vs 6.99 +/- 0.02; p < 0.02). CONCLUSIONS The authors found an altered energy state of the residual cell population investigated. Together with previously identified replacement of white matter by CSF, the present findings raise the possibility that the genetic defect in eIF2B may result in impairment of myelin membrane synthesis or myelin membrane transport in the in vivo CACH brain. Ethanolamine metabolites constitute the plasmalogens, and the present findings may include a defect in plasmalogen metabolism.
Collapse
Affiliation(s)
- S Blüml
- Magnetic Resonance Spectroscopy Unit, Huntington Medical Research Institutes, Pasadena, CA 91105, USA
| | | | | | | | | |
Collapse
|
35
|
Kunz-Schughart LA, Freyer JP. Phosphorous metabolites and steady-state energetics of transformed fibroblasts during three-dimensional growth. Am J Physiol Cell Physiol 2002; 283:C1287-97. [PMID: 12225991 DOI: 10.1152/ajpcell.00097.2002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Rat1-T1 and MR1 spheroids represent separate transformed phenotypes originated from the same rat fibroblasts that differ in three-dimensional (3D) growth kinetics, histological structure, and oxygenation status. In the present study, (31)P-NMR spectroscopy of perfused spheroid suspensions was used to investigate cellular energetics relative to 3D growth, development of necrosis, and cell cycle distribution. Both spheroid types were characterized by a remarkably low amount of free (inorganic) phosphate (P(i)) and a low phosphocreatine peak. The ratio of nucleoside triphosphate (NTP) to P(i) ranged between 1.5 and 2.0. Intracellular pH, NTP-to-P(i) ratio, and NTP/cell remained constant throughout spheroid growth, being unaffected by the emergence of oxygen deficiency, cell quiescence, and necrosis. However, a 50% decrease in the ratio of the lipid precursors phosphorylcholine and phosphorylethanolamine (PC/PE) was observed with increasing spheroid size and was correlated with an increased G(1)/G(0) phase cell fraction. In addition, the ratio of the phospholipid degradation products glycerophosphorylcholine and glycerophosphorylethanolamine (GPC/GPE) increased with spheroid diameter in Rat1-T1 aggregates. We conclude that changes in phospholipid metabolism, rather than alterations in energy-rich phosphates, reflect cell quiescence in spheroid cultures, because cells in the inner oxygen-deficient zones seem to adapt their energy metabolism to the environmental conditions before necrotic cell destruction.
Collapse
Affiliation(s)
- Leoni A Kunz-Schughart
- Langham Resource, Bioscience Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | | |
Collapse
|
36
|
Tzika AA, Cheng LL, Goumnerova L, Madsen JR, Zurakowski D, Astrakas LG, Zarifi MK, Scott RM, Anthony DC, Gonzalez RG, Black PM. Biochemical characterization of pediatric brain tumors by using in vivo and ex vivo magnetic resonance spectroscopy. J Neurosurg 2002; 96:1023-31. [PMID: 12066902 DOI: 10.3171/jns.2002.96.6.1023] [Citation(s) in RCA: 92] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECT Magnetic resonance (MR) spectroscopy provides biochemical information about tumors. The authors sought to determine the relationship between in vivo and ex vivo biochemical characterization of pediatric brain tumors by using MR spectroscopy. Their hypothesis was that ex vivo MR spectroscopy provides a link between in vivo MR spectroscopy and neuropathological analysis. METHODS In vivo proton MR spectroscopy was performed before surgery in 11 patients with neuroepithelial tumors. During resection, a total of 40 tumor biopsy samples were obtained from within the volume of interest identified on in vivo MR spectroscopy and were frozen immediately in liquid nitrogen. High-Resolution Magic Angle Spinning (HRMAS) was used to perform ex vivo MR spectroscopy in these 40 tumor biopsy samples. Neuropathological analysis was performed using the same biopsy samples, and the tumors were classified as ependymoma, choroid plexus carcinoma, pineoblastoma (one each), and pilocytic astrocytoma, medullobastoma, low-grade glioma, and glioblastoma multiforme (two each). Ex vivo HRMAS MR spectroscopy improved line widths and line shapes in the spectra, compared with in vivo MR spectroscopy. Choline (Cho) detected in vivo corresponded to three different peaks ex vivo (glycerophosphocholine, phosphocholine [PCho], and Cho). Metabolite ratios from in vivo spectra correlated with ratios from ex vivo spectra (Pearson correlation coefficient range r = 0.72-0.91; p < or = 0.01). Metabolite ratios from ex vivo spectra, such as PCho/ total creatine (tCr) and lipid/tCr, correlated with the percentage of cancerous tissue and percentage of tumor necrosis, respectively (r = 0.84; p < 0.001). CONCLUSIONS Agreement between in vivo and ex vivo MR spectroscopy indicates that ex vivo HRMAS MR spectroscopy can improve resolution of this modality and provide a link between in vivo MR spectroscopy and neuropathological analysis.
Collapse
Affiliation(s)
- A Aria Tzika
- Department of Radiology, Massachusetts General Hospital, Harvard Medical School, and Shriners Burns Institute, Boston, 02114, USA.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
37
|
Long RC, Papas KK, Sambanis A, Constantinidis I. In vitro monitoring of total choline levels in a bioartificial pancreas: (1)H NMR spectroscopic studies of the effects of oxygen level. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2000; 146:49-57. [PMID: 10968957 DOI: 10.1006/jmre.2000.2112] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
This investigation implements specifically designed solvent-suppressed adiabatic pulses whose properties make possible the long-term monitoring of (1)H NMR detectable metabolites from alginate/poly-l-lysine/alginate (APA)-encapsulated betaTC3 cells. Our encapsulated preparations were maintained in a perfusion bioreactor for periods exceeding 30 days. During this prolonged cultivation period, the cells were exposed to repetitive hypoxic episodes of 4 and 24 h. The ratio of the total choline signal (3.20 ppm) to the reference signal (observed at 0.94 ppm assigned to isoleucine, leucine, and valine) decreased by 8-10% for the 4-h and by 20-32% for the 24-h episodes and returned to its prehypoxic level upon reoxygenation. The decrease in the mean value of total choline to reference signal ratio for three 4-h and two 24-h episodes in two different cultures was highly significant (P<0.01). The rate of recovery by this ratio was slower than the rates of recovery by oxygen consumption, lactate production, or glucose consumption. A step-up in oxygen level led to a new, higher value for the total choline to reference ratio. From spectra of extracts at 400 MHz, it was determined that 63.6% of the total choline signal is due to intracellular phosphorylcholine. Therefore, it is inferred that the observed changes in total choline signal are linked to an oxygen level dependence of the intracellular phosphorylcholine. Several possible mechanisms in which oxygen may influence phosphorylcholine metabolism are suggested. In addition, the implications of these findings to the development of a noninvasive monitoring method for tissue-engineered constructs composed of encapsulated cells are discussed.
Collapse
Affiliation(s)
- R C Long
- Frederik Philips Magnetic Resonance Research Center, Emory University School of Medicine, Atlanta, Georgia, 30322, USA
| | | | | | | |
Collapse
|
38
|
Ling CC, Humm J, Larson S, Amols H, Fuks Z, Leibel S, Koutcher JA. Towards multidimensional radiotherapy (MD-CRT): biological imaging and biological conformality. Int J Radiat Oncol Biol Phys 2000; 47:551-60. [PMID: 10837935 DOI: 10.1016/s0360-3016(00)00467-3] [Citation(s) in RCA: 654] [Impact Index Per Article: 27.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
PURPOSE The goals of this study were to survey and summarize the advances in imaging that have potential applications in radiation oncology, and to explore the concept of integrating physical and biological conformality in multidimensional conformal radiotherapy (MD-CRT). METHODS AND MATERIALS The advances in three-dimensional conformal radiotherapy (3D-CRT) have greatly improved the physical conformality of treatment planning and delivery. The development of intensity-modulated radiotherapy (IMRT) has provided the "dose painting" or "dose sculpting" ability to further customize the delivered dose distribution. The improved capabilities of nuclear magnetic resonance imaging and spectroscopy, and of positron emission tomography, are beginning to provide physiological and functional information about the tumor and its surroundings. In addition, molecular imaging promises to reveal tumor biology at the genotype and phenotype level. These developments converge to provide significant opportunities for enhancing the success of radiotherapy. RESULTS The ability of IMRT to deliver nonuniform dose patterns by design brings to fore the question of how to "dose paint" and "dose sculpt", leading to the suggestion that "biological" images may be of assistance. In contrast to the conventional radiological images that primarily provide anatomical information, biological images reveal metabolic, functional, physiological, genotypic, and phenotypic data. Important for radiotherapy, the new and noninvasive imaging methods may yield three-dimensional radiobiological information. Studies are urgently needed to identify genotypes and phenotypes that affect radiosensitivity, and to devise methods to image them noninvasively. Incremental to the concept of gross, clinical, and planning target volumes (GTV, CTV, and PTV), we propose the concept of "biological target volume" (BTV) and hypothesize that BTV can be derived from biological images and that their use may incrementally improve target delineation and dose delivery. We emphasize, however, that much basic research and clinical studies are needed before this potential can be realized. CONCLUSIONS Whereas IMRT may have initiated the beginning of the end relative to physical conformality in radiotherapy, biological imaging may launch the beginning of a new era of biological conformality. In combination, these approaches constitute MD-CRT that may further improve the efficacy of cancer radiotherapy in the new millennium.
Collapse
Affiliation(s)
- C C Ling
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, NY 10021, USA.
| | | | | | | | | | | | | |
Collapse
|
39
|
Abstract
Following the impetus of early clinical and experimental investigations, in vivo and in vitro MRS studies of tumours pointed in the eighties to the possible significance of signals arising from phospholipid (PL) precursors and catabolites as novel biochemical indicators of in vivo tumour progression and response to therapy. In the present decade, MRS analyses of individual components contributing to the 31P PME (phosphomonoester) and PDE (phosphodiester) resonances, as well as to the 1H 'choline peak', have reinforced some of these expectations. Moreover, the absolute quantification of these signals provided the basis for addressing more specific (although still open) questions on the biochemical mechanisms responsible for the formation of intracellular pools of PL derivatives in tumours, under different conditions of cell proliferative status and/or malignancy level. This article is aimed at providing an overview on: (a) quantitative MRS measurements on the contents of phosphocholine (PCho), phosphoethanolamine (PEtn) and their glycerol derivatives ģlycerol 3-phosphocholine (GPC) and glycerol 3-phosphoethanolamine (GPE)[ in human tumours and cells (with particular attention to breast and brain cancer and lymphomas), as well as in normal mammalian tissues (including developing organs and rapidly proliferating tissues); (b) possible correlations of MRS parameters like PEtn/PCho and PCho/GPC ratios with in vitro cell growth status and/or cell tumorigenicity; and (c) current and new hypotheses on the role and interplay of biosynthetic and catabolic pathways of the choline and ethanolamine cycles in modulating the intracellular sizes of PCho and PEtn pools, either in response to mitogenic stimuli or in relation to malignant transformation.
Collapse
Affiliation(s)
- F Podo
- Laboratory of Cell Biology, Istituto Superiore di Sanità, Rome,
| |
Collapse
|
40
|
Gupta RK, Sinha U, Cloughesy TF, Alger JR. Inverse correlation between choline magnetic resonance spectroscopy signal intensity and the apparent diffusion coefficient in human glioma. Magn Reson Med 1999; 41:2-7. [PMID: 10025604 DOI: 10.1002/(sici)1522-2594(199901)41:1<2::aid-mrm2>3.0.co;2-y] [Citation(s) in RCA: 116] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Magnetic resonance spectroscopy and diffusion magnetic resonance imaging (MRI) characteristics of human intracranial glioma were studied. Present knowledge suggests a hypothetical inverse relationship between the characteristic choline signal intensity elevation and the apparent diffusion coefficient (ADC) in glioma. Twenty cases of glioma were examined with diffusion-weighted echoplanar imaging and proton magnetic resonance spectroscopic imaging (1H-MRSI). A statistically significant inverse correlation between the choline signal intensity and the ADC was found (P = 0.0004) in radiologically defined tumor-containing regions. This study is the first in which diffusion MRI and 1H-MRSI were used to evaluate human intracranial glioma jointly. It provides insight into how to interpret choline signal intensity elevation in terms of tumor cellularity and proliferative potential when ADC images are also available.
Collapse
Affiliation(s)
- R K Gupta
- Department of Radiological Sciences, University of California, Los Angeles 90095-1721, USA
| | | | | | | |
Collapse
|
41
|
Abstract
Magnetic resonance spectroscopy (MRS) remains the technique of choice for observing tumour metabolism non-invasively. Although initially 31P MR spectroscopy showed much promise as a non-invasive diagnostic tool, studies of a wide range of hepatic tumours have conclusively shown that this technique cannot be utilized to distinguish between different tumour types. This lack of specificity and sensitivity appears to be a consequence of the fact that hepatic tumours develop with a range of modalities and not as a single abnormal disease process, and also because of the limited availability of MR detectable metabolic markers. This has led, in recent years, to a re-evaluation of the role of 31P MR spectroscopy, re-emerging as a non-invasive tool to follow the efficacy of the treatment regime. Furthermore, since the principal changes observed in tumours by 31P MRS appear to be an elevation in the concentration of phosphorylcholine (PCho) and phosphoethanolamine (PEth), new research using a combination of MRS and tissue culture of cell lines which carry a combination of known inducible oncogenes, are helping to elucidate some of the metabolic pathways that give rise to these metabolic alterations.
Collapse
Affiliation(s)
- J D Bell
- MR Unit, Hammersmith Hospital, London, UK.
| | | |
Collapse
|
42
|
Lazareff JA, Bockhorst KH, Curran J, Olmstead C, Alger JR. Pediatric low-grade gliomas: prognosis with proton magnetic resonance spectroscopic imaging. Neurosurgery 1998; 43:809-17; discussion 817-8. [PMID: 9766308 DOI: 10.1097/00006123-199810000-00053] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
OBJECTIVE Our aim was to assess the correlation between the low-grade glioma (LGG) metabolic profile and tumor progression. Using in vivo proton magnetic resonance spectroscopic imaging, we specifically asked whether and which metabolic features are associated with tumor regrowth or recurrence. METHODS Eleven pediatric patients with histologically proven partially resected (<20% resection) midline LGG were treated and followed up for a period of 2 years. All patients underwent proton magnetic resonance spectroscopic imaging studies before any management was determined. Tumor progression was defined as radiological evidence of mass enlargement (>25%) during the follow-up period. Proton magnetic resonance spectroscopic imaging was performed using a PRESS-CSI sequence on a General Electric 1.5-tesla scanner (General Electric Medical System, Waukesha, WI). The signal intensities of N-acetylaspartate, choline (CHO), and creatine from the tumor and the normal brain were used to calculate normalized metabolite intensities and metabolite ratios. RESULTS Tumors that progressed during a 2-year period displayed higher normalized CHO than those that remained stable (Mann-Whitney test, P < 0.03). The majority (five of six) of the rapidly growing LGG showed values of normalized CHO of at least 1, whereas the nonprogressors had a normalized CHO value of less than 1. CONCLUSION In association with pediatric LGG, high normalized CHO values seem to herald the potential for rapid tumor growth. These observations may be valuable for defining subsets of patients with LGG who may benefit from early therapeutic interventions.
Collapse
Affiliation(s)
- J A Lazareff
- Division of Neurosurgery, University of California, Los Angeles, 90095-7039, USA
| | | | | | | | | |
Collapse
|
43
|
Mancuso A, Sharfstein ST, Fernandez EJ, Clark DS, Blanch HW. Effect of extracellular glutamine concentration on primary and secondary metabolism of a murine hybridoma: An in vivo13C nuclear magnetic resonance study. Biotechnol Bioeng 1998. [DOI: 10.1002/(sici)1097-0290(19980120)57:2<172::aid-bit6>3.0.co;2-k] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|
44
|
Street JC, Alfieri AA, Traganos F, Koutcher JA. In vivo and ex vivo study of metabolic and cellular effects of 5-fluorouracil chemotherapy in a mouse mammary carcinoma. Magn Reson Imaging 1997; 15:587-96. [PMID: 9254003 DOI: 10.1016/s0730-725x(97)00013-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The effect of 5-fluorouracil (5FU) on the 31P nuclear magnetic resonance (NMR) profile of a mouse mammary carcinoma, implanted on the foot of CH3/He mice, was studied both in vivo and in perchloric acid extracts. In vivo, significant increases in the ratios, nucleotide triphosphate:inorganic phosphate (Pi) (p < 0.02) and phosphocreatine:Pi (p < 0.005), were observed 48 h after 5FU, relative to control. Two readily resolvable peaks were observed in the phosphomonoester region of the in vivo NMR spectrum, phosphocholine (PC) and a peak (denoted PME') comprised of mainly phosphoethanolamine (PE). PME':PC was significantly elevated relative to control from 24 h to 168 h (p < 0.0001 at 48 h). Perchloric acid extract data indicate that the change in this ratio was due to an increase in the PE concentration rather than a decrease in PC. PE increased from 0.56 +/- 0.11 micromol/g tissue in controls to 0.95 +/- 0.29 micromol/g tissue 48 h after 5FU (p < 0.006). Perchloric acid extracts also revealed a significant increase in phosphodiesters. Glycerophosphocholine increased from 0.82 +/- 0.24 micromol/g tissue in controls to 1.82 +/- 0.61 micromol/g tissue in 5FU treated tumors after 48 h (p < 0.002), and glycerophosphoethanolamine increased from 0.25 +/- 0.06 micromol/g tissue in controls to 0.36 +/- 0.10 micromol/g tissue in treated tumors (p < 0.004). These changes suggest that ethanolamine and choline containing metabolites in this tumor may be metabolized via different pathways. Cell cycle analysis showed only relatively small changes in cell cycle distribution and apoptotic fraction following 5FU.
Collapse
Affiliation(s)
- J C Street
- Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, NY 10021, USA.
| | | | | | | |
Collapse
|
45
|
Stegman LD, Ben-Yoseph O, Freyer JP, Ross BD. In vivo 31P MRS evaluation of ganciclovir toxicity in C6 gliomas stably expressing the herpes simplex thymidine kinase gene. NMR IN BIOMEDICINE 1996; 9:364-368. [PMID: 9176891 DOI: 10.1002/(sici)1099-1492(199612)9:8<364::aid-nbm436>3.0.co;2-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Phosphorus MRS was evaluated as a monitor of tumour therapeutic response to the herpes simplex virus thymidine kinase suicide gene therapy paradigm. In vivo 31P spectra were obtained from subcutaneous rat C6 gliomas constitutively expressing the HSVtk gene post treatment with ganciclovir (GCV, 15 mg/kg i.p., twice-daily). Significant regression (p < 0.1) of tumour volume was observed 10 days after beginning GCV administration. However, no changes in tumour pH or energy metabolites from pre-treatment values were observed. High-resolution 31P spectra of tumour extracts revealed a statistically significant reduction in the phosphocholine to phosphoethanolamine ratio six days post-GCV administration. These results indicate that the HSVtk/GCV-induced killing of tumours is not associated with corresponding changes in 31P MRS-observable energy metabolites and pH. The observed reduction in the PE/PC ratio may provide a non-invasive in vivo indicator of therapeutic efficacy.
Collapse
Affiliation(s)
- L D Stegman
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor 48109, USA
| | | | | | | |
Collapse
|
46
|
Street JC, Mahmood U, Matei C, Koutcher JA. In vivo and in vitro studies of cyclophosphamide chemotherapy in a mouse mammary carcinoma by 31P NMR spectroscopy. NMR IN BIOMEDICINE 1995; 8:149-158. [PMID: 8771089 DOI: 10.1002/nbm.1940080403] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The effect of cyclophosphamide on the metabolic profile of a mammary carcinoma implanted on the foot of mouse was studied by 31P NMR spectroscopy both in vivo and in perchloric acid extracts. The ratio nucleotide triphosphate:P(i) was significantly elevated in cyclophosphamide treated tumours relative to untreated tumours after 96 h in vivo (p < 0.05). Phosphocreatine:P(i) was similarly elevated from 48 to 168 h (p < 0.01). Resolution of the phosphomonoester peak into two distinct resonances allowed us to estimate the ratio of PME' to phosphocholine (PC), where PME' is a composite peak consisting, in part, of phosphoethanolamine (PE). PME':PC was found to be significantly higher in treated animals relative to control animals in vivo (p < 0.01 from 48 to 168 h). Perchloric acid extract spectra suggest that the increase in PME':PC was in part due to a decrease in PC concentration and also due to an increase in a previously unidentified resonance which was coresonant with PE. Extract data show that there was a significant increase in the concentration of the phosphodiesters, glycerophosphocholine (p < 0.01) and glycerophosphoethanolamine (p < 0.05) in treated relative to control tumours. The changes in the phosphomonoester resonances are qualitatively similar to previously described changes following radiation and suggest that they may be a marker of cell kill or lack of cell growth after antineoplastic therapy.
Collapse
Affiliation(s)
- J C Street
- Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, NY 10021, USA
| | | | | | | |
Collapse
|