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Liu F, Zhao B, Xia XT, Yan JR, Yu FQ, Yan GP, Hu J, Chen S, Wang YF, Liu H, Lan XL, Zhang YX. Al 18 F labeled sulfonamide-conjugated positron emission tomography tracer in vivo tumor-targeted imaging. J Cell Biochem 2019; 120:17006-17014. [PMID: 31131464 DOI: 10.1002/jcb.28961] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Accepted: 03/06/2019] [Indexed: 01/01/2023]
Abstract
An ideal positron emission tomography (PET) tracer should be highly extractable by the tumor tissue or organ that contains low toxicity and can provide high-resolution images in vivo. In this work, the aim was to evaluate the application of Al18 F-labeled 1,4,7-triazacyclononane-1,4,7-triacetic acid containing sulfonamide group (18 F-Al-NOTA-SN) as a potential tumor-targeting signal-enhanced radioactive tracer in PET. SN as a tumor-targeting group was incorporated to NOTA to make a ligand. Subsequently, this ligand reacted with Na18 F and AlCl3 to produce a compound 18 F-Al-NOTA-SN. This compound was further characterized and its property in regard to cell cytotoxicity assay, microPET imaging, biodistribution, cell uptake assay, and tumor selectivity in vitro and in vivo, was also investigated. 18 F-Al-NOTA-SN possessed low cell cytotoxicity and uptake to COS-7 and 293T healthy cells and high cell cytotoxicity and uptake to MDA-MB-231, HepG2, and HeLa tumor cells in vitro. Moreover, 18 F-Al-NOTA-SN showed good tumor-targeting property and high PET signal enhancement of HeLa tumors, liver, and kidneys in mice, as well as the uptake ratios of tumor to blood and tumor to muscle, were 4.98 and 3.87, respectively. 18 F-Al-NOTA-SN can be accepted to be kidney and liver eliminated earlier and show a potential tumor-targeting signal-enhanced radioactive tracer in PET.
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Affiliation(s)
- Fan Liu
- School of Chemical Engineering and Pharmacy, Wuhan Institute of Technology, Wuhan, China.,School of Chemistry, Physics, and Mechanical Engineering, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Biao Zhao
- School of Materials Science and Engineering, Wuhan Institute of Technology, Wuhan, China
| | - Xiao-Tian Xia
- Center for PET of Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jia-Rui Yan
- School of Materials Science and Engineering, Wuhan Institute of Technology, Wuhan, China
| | - Fa-Quan Yu
- School of Chemical Engineering and Pharmacy, Wuhan Institute of Technology, Wuhan, China
| | - Guo-Ping Yan
- School of Materials Science and Engineering, Wuhan Institute of Technology, Wuhan, China
| | - Jia Hu
- Center for PET of Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Si Chen
- School of Materials Science and Engineering, Wuhan Institute of Technology, Wuhan, China
| | - Yu-Fang Wang
- School of Materials Science and Engineering, Wuhan Institute of Technology, Wuhan, China
| | - Hui Liu
- School of Materials Science and Engineering, Wuhan Institute of Technology, Wuhan, China
| | - Xiao-Li Lan
- Center for PET of Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yong-Xue Zhang
- Center for PET of Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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Plotnik DA, Wu S, Linn GR, Yip FCT, Comandante NL, Krohn KA, Toyohara J, Schwartz JL. In vitro analysis of transport and metabolism of 4'-thiothymidine in human tumor cells. Nucl Med Biol 2014; 42:470-474. [PMID: 25659855 PMCID: PMC4387014 DOI: 10.1016/j.nucmedbio.2014.12.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2014] [Revised: 11/19/2014] [Accepted: 12/01/2014] [Indexed: 01/11/2023]
Abstract
Introduction The use of thymidine (TdR) and thymidine analogs such as 3′-fluoro-3′-deoxythymidine (FLT) as positron emission tomography (PET)-based proliferation markers can provide information on tumor response to treatment. Studies on another TdR analog, 4'-thiothymidine (4DST), suggest that it might be a better PET-based proliferation tracer than either TdR or FLT. 4DST is resistant to the catabolism that complicates analysis of TdR in PET studies, but unlike FLT, 4DST is incorporated into DNA. Methods To further evaluate 4DST, the kinetics of 4DST transport and metabolism were determined and compared to FLT and TdR. Transport and metabolism of FLT, TdR and 4DST were examined in the human adenocarcinoma cell line A549 under exponential-growth conditions. Single cell suspensions were incubated in buffer supplemented with radiolabeled tracer in the presence or absence of nitrobenzylmercaptopurine ribonucleoside (NBMPR), an inhibitor of equilibrative nucleoside transporters (ENT). Kinetics of tracer uptake was determined in whole cells and tracer metabolism measured by high performance liquid chromatography of cell lysates. Results TdR and 4DST were qualitatively similar in terms of ENT-dependent transport, shapes of uptake curves, and relative levels of DNA incorporation. FLT did not incorporate into DNA, showed a significant temperature effect for uptake, and its transport had a significant NBMPR-resistant component. Overall 4DST metabolism was significantly slower than either TdR or FLT. Conclusions 4DST provides a good alternative for TdR in PET and has advantages over FLT in proliferation measurement. However, slow 4DST metabolism and the short half-life of the 11C label might limit widespread use in PET.
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Affiliation(s)
- David A Plotnik
- Department of Radiation Oncology, University of Washington, Seattle, WA
| | - Stephen Wu
- Department of Radiation Oncology, University of Washington, Seattle, WA
| | - Geoffrey R Linn
- Department of Radiation Oncology, University of Washington, Seattle, WA
| | | | | | - Kenneth A Krohn
- Department of Radiation Oncology, University of Washington, Seattle, WA; Department of Radiology, University of Washington, Seattle, WA
| | - Jun Toyohara
- Research Team for Neuroimaging, Tokyo Metropolitan Institute of Gerontology, Tokyo, Japan
| | - Jeffrey L Schwartz
- Department of Radiation Oncology, University of Washington, Seattle, WA.
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Plotnik DA, Emerick LE, Krohn KA, Unadkat JD, Schwartz JL. Different modes of transport for 3H-thymidine, 3H-FLT, and 3H-FMAU in proliferating and nonproliferating human tumor cells. J Nucl Med 2010; 51:1464-71. [PMID: 20720049 DOI: 10.2967/jnumed.110.076794] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
UNLABELLED The basis for the use of nucleoside tracers in PET is that activity of the cell-growth-dependent enzyme thymidine kinase 1 is the rate-limiting factor driving tracer retention in tumors. Recent publications suggest that nucleoside transporters might influence uptake and thereby affect the tracer signal in vivo. Understanding transport mechanisms for different nucleoside PET tracers is important for evaluating clinical results. This study examined the relative role of different nucleoside transport mechanisms in uptake and retention of [methyl-(3)H]-3'-deoxy-3'-fluorothymidine ((3)H-FLT), [methyl-(3)H]-thymidine ((3)H-thymidine), and (3)H-1-(2-deoxy-2-fluoro-beta-D-arabinofuranosyl)-5-methyluracil ((3)H-FMAU). METHODS Transport of (3)H-FLT, (3)H-thymidine, and (3)H-FMAU was examined in a single human adenocarcinoma cell line, A549, under both nongrowth and exponential-growth conditions. RESULTS (3)H-Thymidine transport was dominated by human equilibrative nucleoside transporter 1 (hENT1) under both growth conditions. (3)H-FLT was also transported by hENT1, but passive diffusion dominated its transport. (3)H-FMAU transport was dominated by human equilibrative nucleoside transporter 2. Cell membrane levels of hENT1 increased in cells under exponential growth, and this increase was associated with a more rapid rate of uptake for both (3)H-thymidine and (3)H-FLT. (3)H-FMAU transport was not affected by changes in growth conditions. All 3 tracers concentrated in the plateau phase, nonproliferating cells at levels many-fold greater than their concentration in buffer, in part because of low levels of nucleoside metabolism, which inhibited tracer efflux. CONCLUSION Transport mechanisms are not the same for (3)H-thymidine, (3)H-FLT, and (3)H-FMAU. Levels of hENT1, an important transporter of (3)H-FLT and (3)H-thymidine, increase as proliferating cells enter the cell cycle.
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Affiliation(s)
- David A Plotnik
- Department of Radiation Oncology, University of Washington, Seattle, Washington 98195, USA
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Galbán CJ, Bhojani MS, Lee KC, Meyer CR, Van Dort M, Kuszpit K, Koeppe RA, Ranga R, Moffat BA, Johnson TD, Chenevert TL, Rehemtulla A, Ross BD. Evaluation of treatment-associated inflammatory response on diffusion-weighted magnetic resonance imaging and 2-[18F]-fluoro-2-deoxy-D-glucose-positron emission tomography imaging biomarkers. Clin Cancer Res 2010; 16:1542-52. [PMID: 20160061 PMCID: PMC2843556 DOI: 10.1158/1078-0432.ccr-08-1812] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE Functional imaging biomarkers of cancer treatment response offer the potential for early determination of outcome through the assessment of biochemical, physiologic, and microenvironmental readouts. Cell death may result in an immunologic response, thus complicating the interpretation of biomarker readouts. This study evaluated the temporal effect of treatment-associated inflammatory activity on diffusion magnetic resonance imaging and 2-[(18)F]-fluoro-2-deoxy-D-glucose-positron emission tomography imaging (FDG-PET) biomarkers to delineate the effects of the inflammatory response on imaging readouts. EXPERIMENTAL DESIGN Rats with intracerebral 9L gliosarcomas were separated into four groups consisting of control, an immunosuppressive agent dexamethasone (Dex), 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU), and BCNU+Dex. Animals were imaged using diffusion-weighted magnetic resonance imaging and FDG-PET at 0, 3, and 7 days posttreatment. RESULTS In the BCNU- and BCNU+Dex-treated animal groups, diffusion values increased progressively over the 7-day study period to approximately 23% over baseline. The FDG percentage change of standard uptake value decreased at day 3 (-30.9%) but increased over baseline levels at day 7 (+20.1%). FDG-PET of BCNU+Dex-treated animals were found to have percentage of standard uptake value reductions of -31.4% and -24.7% at days 3 and 7, respectively, following treatment. Activated macrophages were observed on day 7 in the BCNU treatment group with much fewer found in the BCNU+Dex group. CONCLUSIONS Results revealed that treatment-associated inflammatory response following tumor therapy resulted in the accentuation of tumor diffusion response along with a corresponding increase in tumor FDG uptake due to the presence of glucose-consuming activated macrophages. The dynamics and magnitude of potential inflammatory response should be considered when interpreting imaging biomarker results.
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Affiliation(s)
- Craig J. Galbán
- Center for Molecular Imaging, University of Michigan, School of Medicine, Ann Arbor, Michigan
- Department of Radiology, University of Michigan, School of Medicine, Ann Arbor, Michigan
| | - Mahaveer S Bhojani
- Center for Molecular Imaging, University of Michigan, School of Medicine, Ann Arbor, Michigan
- Department of Radiation Oncology, University of Michigan, School of Medicine, Ann Arbor, Michigan
| | - Kuei C. Lee
- Center for Molecular Imaging, University of Michigan, School of Medicine, Ann Arbor, Michigan
- Department of Radiology, University of Michigan, School of Medicine, Ann Arbor, Michigan
| | - Charles R. Meyer
- Center for Molecular Imaging, University of Michigan, School of Medicine, Ann Arbor, Michigan
- Department of Radiology, University of Michigan, School of Medicine, Ann Arbor, Michigan
| | - Marcian Van Dort
- Center for Molecular Imaging, University of Michigan, School of Medicine, Ann Arbor, Michigan
- Department of Radiology, University of Michigan, School of Medicine, Ann Arbor, Michigan
| | - Kyle Kuszpit
- Center for Molecular Imaging, University of Michigan, School of Medicine, Ann Arbor, Michigan
- Department of Radiology, University of Michigan, School of Medicine, Ann Arbor, Michigan
| | - Robert A. Koeppe
- Department of Radiology, University of Michigan, School of Medicine, Ann Arbor, Michigan
| | - Rajesh Ranga
- Department of Radiation Oncology, University of Michigan, School of Medicine, Ann Arbor, Michigan
| | - Bradford A. Moffat
- Center for Molecular Imaging, University of Michigan, School of Medicine, Ann Arbor, Michigan
- Department of Radiology, University of Michigan, School of Medicine, Ann Arbor, Michigan
| | - Timothy D. Johnson
- Department of Biostatistics, University of Michigan, School of Medicine, Ann Arbor, Michigan
| | - Thomas L. Chenevert
- Center for Molecular Imaging, University of Michigan, School of Medicine, Ann Arbor, Michigan
- Department of Radiology, University of Michigan, School of Medicine, Ann Arbor, Michigan
| | - Alnawaz Rehemtulla
- Center for Molecular Imaging, University of Michigan, School of Medicine, Ann Arbor, Michigan
- Department of Radiology, University of Michigan, School of Medicine, Ann Arbor, Michigan
- Department of Radiation Oncology, University of Michigan, School of Medicine, Ann Arbor, Michigan
| | - Brian D. Ross
- Center for Molecular Imaging, University of Michigan, School of Medicine, Ann Arbor, Michigan
- Department of Radiology, University of Michigan, School of Medicine, Ann Arbor, Michigan
- Department of Biological Chemistry, University of Michigan, School of Medicine, Ann Arbor, Michigan
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O’Sullivan F, Kirrane J, Muzi M, O’Sullivan JN, Spence AM, Mankoff DA, Krohn KA. Kinetic quantitation of cerebral PET-FDG studies without concurrent blood sampling: statistical recovery of the arterial input function. IEEE TRANSACTIONS ON MEDICAL IMAGING 2010; 29:610-24. [PMID: 19709971 PMCID: PMC4154632 DOI: 10.1109/tmi.2009.2029096] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Kinetic quantitation of dynamic positron emission tomography (PET) studies via compartmental modeling usually requires the time-course of the radio-tracer concentration in the arterial blood as an arterial input function (AIF). For human and animal imaging applications, significant practical difficulties are associated with direct arterial sampling and as a result there is substantial interest in alternative methods that require no blood sampling at the time of the study. A fixed population template input function derived from prior experience with directly sampled arterial curves is one possibility. Image-based extraction, including requisite adjustment for spillover and recovery, is another approach. The present work considers a hybrid statistical approach based on a penalty formulation in which the information derived from a priori studies is combined in a Bayesian manner with information contained in the sampled image data in order to obtain an input function estimate. The absolute scaling of the input is achieved by an empirical calibration equation involving the injected dose together with the subject's weight, height and gender. The technique is illustrated in the context of (18)F -Fluorodeoxyglucose (FDG) PET studies in humans. A collection of 79 arterially sampled FDG blood curves are used as a basis for a priori characterization of input function variability, including scaling characteristics. Data from a series of 12 dynamic cerebral FDG PET studies in normal subjects are used to evaluate the performance of the penalty-based AIF estimation technique. The focus of evaluations is on quantitation of FDG kinetics over a set of 10 regional brain structures. As well as the new method, a fixed population template AIF and a direct AIF estimate based on segmentation are also considered. Kinetics analyses resulting from these three AIFs are compared with those resulting from radially sampled AIFs. The proposed penalty-based AIF extraction method is found to achieve significant improvements over the fixed template and the segmentation methods. As well as achieving acceptable kinetic parameter accuracy, the quality of fit of the region of interest (ROI) time-course data based on the extracted AIF, matches results based on arterially sampled AIFs. In comparison, significant deviation in the estimation of FDG flux and degradation in ROI data fit are found with the template and segmentation methods. The proposed AIF extraction method is recommended for practical use.
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Affiliation(s)
- F. O’Sullivan
- Statistics Department, University College, Cork, Ireland
| | - J. Kirrane
- Statistics Department, University College, Cork, Ireland
| | - M. Muzi
- Department of Radiology, University of Washington, Seattle, WA 98195 USA
| | | | - A. M. Spence
- Department of Neurology, University of Washington, Seattle, WA 98195 USA
| | - D. A. Mankoff
- Department of Radiology, University of Washington, Seattle, WA 98195 USA
| | - K. A. Krohn
- Department of Radiology, University of Washington, Seattle, WA 98195 USA
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Abstract
Neuroimaging plays a crucial role in establishing the diagnosis, planning the therapy, as well as evaluating therapeutic effects and detecting early recurrence in brain tumors. It has evolved from a morphology-driven discipline to the multimodal assessment of CNS lesions, incorporating biochemistry (e.g., indicators of cell membrane synthesis) as well as physiologic parameters (e.g., hemodynamic variables). Tumor cellularity, metabolism, and angiogenesis are important predictors for tumor grading, therapy, and prognosis, all of which are provided by dedicated use of advanced magnetic resonance imaging (MRI) techniques by the neuroradiologist. Unprecedented views of tumor-affected brain cytoarchitecture are yielded by diffusion tensor imaging and tractography, discriminating between displacement and infiltration of highly relevant white matter tracts and guiding the neurosurgeon's CNS approach. Functional MRI (fMRI) visualizes the spatial relationship between functionally important areas and the tumor site. Many of these techniques use superimposition on high-anatomic-resolution MR images within the submillimeter range, in order to assure precise stereotactic proceedings. Yet, the borders of neuroimaging are subject to constant updating.Molecular imaging has become one of the most promising research areas, as the molecular fingerprint of the tumor is required for targeting chemotherapy-resistant, migrating glial tumor cells.
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Affiliation(s)
- R Klingebiel
- Department of Neuroradiology, Charité - Universitätsmedizin Berlin, Charitéplatz 1, Berlin 10117, Germany.
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Gabilondo AM, Hostalot C, Garibi JM, Meana JJ, Callado LF. Monoamine oxidase B activity is increased in human gliomas. Neurochem Int 2008; 52:230-4. [PMID: 17624626 DOI: 10.1016/j.neuint.2007.05.015] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2007] [Revised: 05/17/2007] [Accepted: 05/23/2007] [Indexed: 12/25/2022]
Abstract
Glial tumours are the most common type of brain neoplasm in humans. Tumour classification and grading represent key factors for patient management. However, current grading schemes are still limited by subjective histological criteria. In this context, gliosis has been linked to increases in monoamine oxidase B (MAO-B) activity. Thus, in the present study, MAO-B activity in membranes of glial tumours (n=20), meningiomas (n=12) and non-pathological human brains (n=15) was quantified by [14C]PEA oxidation. MAO-B activity was significantly greater in glioblastoma multiformes than in postmortem control brains (p<0.01) or meningiomas (p<0.001). There were no significant differences in MAO-B activity between glioblastoma multiformes (n=11) and low-grade astrocytomas (n=3) or anaplastic astrocytomas (n=6). In conclusion, the present results demonstrate a significant and selective increase in MAO-B activity in human gliomas when compared with meningiomas or non-tumoural tissue. These results suggest that the quantification of MAO-B activity may be a useful diagnostic tool for differentiating glial tumours from other types of brain tumours or surrounding normal brain tissue.
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Affiliation(s)
- Ane M Gabilondo
- Department of Pharmacology, University of the Basque Country, E-48940 Leioa, Bizkaia, and Neurosurgery Service, Cruces Hospital, Spain
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Abstract
The prognosis for patients with malignant primary brain tumors has been poor, and until recently, there was little evidence that chemotherapy was beneficial. The publication of the phase III trial comparing the combination of temozolomide with external beam radiation therapy with radiation therapy alone demonstrated a clear survival benefit for the combination regimen. These results, along with improvements in clinical trial design and outcome assessment, advances in our understanding of glioma tumor biology, and recognition of critical drug-drug interactions, have provided a foundation for developing better treatments for these cancers.
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Affiliation(s)
- Mark R Gilbert
- Department of Neuro-oncology, The University of Texas M. D. Anderson Cancer Center, Houston, TX 77030, USA.
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O'Sullivan F. Locally constrained mixture representation of dynamic imaging data from PET and MR studies. Biostatistics 2005; 7:318-38. [PMID: 16361274 DOI: 10.1093/biostatistics/kxj010] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Dynamic positron emission tomography (PET) studies provide measurements of the kinetics of radiotracers in living tissue. This is a powerful technology which can play a major role in the study of biological processes, potentially leading to better understanding and treatment of disease. Dynamic PET data relate to complex spatiotemporal processes and its analysis poses significant challenges. In previous work, mixture models that expressed voxel-level PET time course data as a convex linear combination of a finite number of dominant time course characteristics (called sub-TACs) were introduced. This paper extends that mixture model formulation to allow for a weighted combination of scaled sub-TACs and also considers the imposition of local constraints in the number of sub-TACs that can be active at any one voxel. An adaptive 3D scaled segmentation algorithm is developed for model initialization. Increases in the weighted residual sums of squares is used to guide the choice of the number of segments and the number of sub-TACs in the final mixture model. The methodology is applied to five data sets from representative PET imaging studies. The methods are also applicable to other contexts in which dynamic image data are acquired. To illustrate this, data from an echo-planar magnetic resonance (MR) study of cerebral hemodynamics are considered. Our analysis shows little indication of departure from a locally constrained mixture model representation with at most two active components at any voxel. Thus, the primary sources of spatiotemporal variation in representative dynamic PET and MR imaging studies would appear to be accessible to a substantially simplified representation in terms of the generalized locally constrained mixture model introduced.
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Chen X, Park R, Khankaldyyan V, Gonzales-Gomez I, Tohme M, Moats RA, Bading JR, Laug WE, Conti PS. Longitudinal MicroPET Imaging of Brain Tumor Growth with F-18-labeled RGD Peptide. Mol Imaging Biol 2005; 8:9-15. [PMID: 16315003 DOI: 10.1007/s11307-005-0024-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
PURPOSE EMD 121974, a potent cyclic RGD peptide inhibitor of alphav-integrins, demonstrated effectiveness in suppressing brain tumor growth in both preclinical models and phases I/II clinical trials. The ability to non-invasively evaluate alphav-integrin expression provides a novel and unique way to better understand brain tumor angiogenesis in relationship to alphav-integrin expression, and allow for direct assessment of anti-integrin treatment efficacy. PROCEDURES We developed a F-18-labeled RGD peptide [F-18]FB-RGD and performed serial microPET imaging scans to follow brain tumor growth and angiogenesis as a function of time in an orthotopic U87MG glioblastoma xenograft model in athymic nude mice. RESULTS The tumor was barely visible on microPET at the size of <or=1.5 mm diameter at which time no angiogenesis was evident on histological examination. When tumor started to grow exponentially by day 35 the activity accumulation in the brain tumor also increased accordingly, with best tumor-to-brain contrast seven weeks after inoculation of 10(5) U87MG cells into the mice forebrain. CONCLUSIONS Longitudinal microPET imaging and [F-18]FB-RGD provides the sensitivity and resolution to visualize and quantify anatomical variations during brain tumor growth and angiogenesis, most likely through interaction with alphav-integrins expressed on tumor cells and angiogenic tumor vessels.
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Affiliation(s)
- Xiaoyuan Chen
- PET Imaging Science Center, Department of Radiology, University of Southern California Keck School of Medicine, Los Angeles, CA 90033, USA.
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Rajendran JG, Mankoff DA, O'Sullivan F, Peterson LM, Schwartz DL, Conrad EU, Spence AM, Muzi M, Farwell DG, Krohn KA. Hypoxia and glucose metabolism in malignant tumors: evaluation by [18F]fluoromisonidazole and [18F]fluorodeoxyglucose positron emission tomography imaging. Clin Cancer Res 2004; 10:2245-52. [PMID: 15073099 DOI: 10.1158/1078-0432.ccr-0688-3] [Citation(s) in RCA: 288] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
PURPOSE The aim of this study is to compare glucose metabolism and hypoxia in four different tumor types using positron emission tomography (PET). (18)F-labeled fluorodeoxyglucose (FDG) evaluates energy metabolism, whereas the uptake of (18)F-labeled fluoromisonidazole (FMISO) is proportional to tissue hypoxia. Although acute hypoxia results in accelerated glycolysis, cellular metabolism is slowed in chronic hypoxia, prompting us to look for discordance between FMISO and FDG uptake. EXPERIMENTAL DESIGN Forty-nine patients (26 with head and neck cancer, 11 with soft tissue sarcoma, 7 with breast cancer, and 5 with glioblastoma multiforme) who had both FMISO and FDG PET scans as part of research protocols through February 2003 were included in this study. The maximum standardized uptake value was used to depict FDG uptake, and hypoxic volume and maximum tissue:blood ratio were used to quantify hypoxia. Pixel-by-pixel correlation of radiotracer uptake was performed on coregistered images for each corresponding tumor plane. RESULTS Hypoxia was detected in all four patient groups. The mean correlation coefficients between FMISO and FDG uptake were 0.62 for head and neck cancer, 0.47 for breast cancer, 0.38 for glioblastoma multiforme, and 0.32 for soft tissue sarcoma. The correlation between the overall tumor maximum standardized uptake value for FDG and hypoxic volume was small (Spearman r = 0.24), with highly significant differences among the different tumor types (P < 0.005). CONCLUSIONS Hypoxia is a general factor affecting glucose metabolism; however, some hypoxic tumors can have modest glucose metabolism, whereas some highly metabolic tumors are not hypoxic, showing discordance in tracer uptake that can be tumor type specific.
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