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Reporter Genes for Brain Imaging Using MRI, SPECT and PET. Int J Mol Sci 2022; 23:ijms23158443. [PMID: 35955578 PMCID: PMC9368793 DOI: 10.3390/ijms23158443] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 07/24/2022] [Accepted: 07/25/2022] [Indexed: 01/14/2023] Open
Abstract
The use of molecular imaging technologies for brain imaging can not only play an important supporting role in disease diagnosis and treatment but can also be used to deeply study brain functions. Recently, with the support of reporter gene technology, optical imaging has achieved a breakthrough in brain function studies at the molecular level. Reporter gene technology based on traditional clinical imaging modalities is also expanding. By benefiting from the deeper imaging depths and wider imaging ranges now possible, these methods have led to breakthroughs in preclinical and clinical research. This article focuses on the applications of magnetic resonance imaging (MRI), single-photon emission computed tomography (SPECT), and positron emission tomography (PET) reporter gene technologies for use in brain imaging. The tracking of cell therapies and gene therapies is the most successful and widely used application of these techniques. Meanwhile, breakthroughs have been achieved in the research and development of reporter genes and their imaging probe pairs with respect to brain function research. This paper introduces the imaging principles and classifications of the reporter gene technologies of these imaging modalities, lists the relevant brain imaging applications, reviews their characteristics, and discusses the opportunities and challenges faced by clinical imaging modalities based on reporter gene technology. The conclusion is provided in the last section.
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Semenova AV, Sivolobova GF, Grazhdantseva AA, Agafonov AP, Kochneva GV. Reporter Transgenes for Monitoring the Antitumor Efficacy of Recombinant Oncolytic Viruses. Acta Naturae 2022; 14:46-56. [PMID: 36348722 PMCID: PMC9611865 DOI: 10.32607/actanaturae.11719] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Accepted: 07/05/2022] [Indexed: 11/29/2022] Open
Abstract
Accurate measurement of tumor size and margins is crucial for successful oncotherapy. In the last decade, non-invasive imaging modalities, including optical imaging using non-radioactive substrates, deep-tissue imaging with radioactive substrates, and magnetic resonance imaging have been developed. Reporter genes play the most important role among visualization tools; their expression in tumors and metastases makes it possible to track changes in the tumor growth and gauge therapy effectiveness. Oncolytic viruses are often chosen as a vector for delivering reporter genes into tumor cells, since oncolytic viruses are tumor-specific, meaning that they infect and lyse tumor cells without damaging normal cells. The choice of reporter transgenes for genetic modification of oncolytic viruses depends on the study objectives and imaging methods used. Optical imaging techniques are suitable for in vitro studies and small animal models, while deep-tissue imaging techniques are used to evaluate virotherapy in large animals and humans. For optical imaging, transgenes of fluorescent proteins, luciferases, and tyrosinases are used; for deep-tissue imaging, the most promising transgene is the sodium/iodide symporter (NIS), which ensures an accumulation of radioactive isotopes in virus-infected tumor cells. Currently, NIS is the only reporter transgene that has been shown to be effective in monitoring tumor virotherapy not only in preclinical but also in clinical studies.
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Affiliation(s)
- A. V. Semenova
- Federal Budgetary Research Institution «State Research Center of Virology and Biotechnology «Vector», Koltsovo, Novosibirsk region, 630559, Russia
| | - G. F. Sivolobova
- Federal Budgetary Research Institution «State Research Center of Virology and Biotechnology «Vector», Koltsovo, Novosibirsk region, 630559, Russia
| | - A. A. Grazhdantseva
- Federal Budgetary Research Institution «State Research Center of Virology and Biotechnology «Vector», Koltsovo, Novosibirsk region, 630559, Russia
| | - A. P. Agafonov
- Federal Budgetary Research Institution «State Research Center of Virology and Biotechnology «Vector», Koltsovo, Novosibirsk region, 630559, Russia
| | - G. V. Kochneva
- Federal Budgetary Research Institution «State Research Center of Virology and Biotechnology «Vector», Koltsovo, Novosibirsk region, 630559, Russia
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Concilio SC, Russell SJ, Peng KW. A brief review of reporter gene imaging in oncolytic virotherapy and gene therapy. Mol Ther Oncolytics 2021; 21:98-109. [PMID: 33981826 PMCID: PMC8065251 DOI: 10.1016/j.omto.2021.03.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Reporter gene imaging (RGI) can accelerate development timelines for gene and viral therapies by facilitating rapid and noninvasive in vivo studies to determine the biodistribution, magnitude, and durability of viral gene expression and/or virus infection. Functional molecular imaging systems used for this purpose can be divided broadly into deep-tissue and optical modalities. Deep-tissue modalities, which can be used in animals of any size as well as in human subjects, encompass single photon emission computed tomography (SPECT), positron emission tomography (PET), and functional/molecular magnetic resonance imaging (f/mMRI). Optical modalities encompass fluorescence, bioluminescence, Cerenkov luminescence, and photoacoustic imaging and are suitable only for small animal imaging. Here we discuss the mechanisms of action and relative merits of currently available reporter gene systems, highlighting the strengths and weaknesses of deep tissue versus optical imaging systems and the hardware/reagents that are used for data capture and processing. In light of recent technological advances, falling costs of imaging instruments, better availability of novel radioactive and optical tracers, and a growing realization that RGI can give invaluable insights across the entire in vivo translational spectrum, the approach is becoming increasingly essential to facilitate the competitive development of new virus- and gene-based drugs.
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Affiliation(s)
| | | | - Kah-Whye Peng
- Department of Molecular Medicine, Mayo Clinic, Rochester, MN 55905, USA
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Physiological Imaging Methods for Evaluating Response to Immunotherapies in Glioblastomas. Int J Mol Sci 2021; 22:ijms22083867. [PMID: 33918043 PMCID: PMC8069140 DOI: 10.3390/ijms22083867] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Revised: 04/05/2021] [Accepted: 04/05/2021] [Indexed: 12/19/2022] Open
Abstract
Glioblastoma (GBM) is the most malignant brain tumor in adults, with a dismal prognosis despite aggressive multi-modal therapy. Immunotherapy is currently being evaluated as an alternate treatment modality for recurrent GBMs in clinical trials. These immunotherapeutic approaches harness the patient's immune response to fight and eliminate tumor cells. Standard MR imaging is not adequate for response assessment to immunotherapy in GBM patients even after using refined response assessment criteria secondary to amplified immune response. Thus, there is an urgent need for the development of effective and alternative neuroimaging techniques for accurate response assessment. To this end, some groups have reported the potential of diffusion and perfusion MR imaging and amino acid-based positron emission tomography techniques in evaluating treatment response to different immunotherapeutic regimens in GBMs. The main goal of these techniques is to provide definitive metrics of treatment response at earlier time points for making informed decisions on future therapeutic interventions. This review provides an overview of available immunotherapeutic approaches used to treat GBMs. It discusses the limitations of conventional imaging and potential utilities of physiologic imaging techniques in the response assessment to immunotherapies. It also describes challenges associated with these imaging methods and potential solutions to avoid them.
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Serganova I, Blasberg RG. Molecular Imaging with Reporter Genes: Has Its Promise Been Delivered? J Nucl Med 2020; 60:1665-1681. [PMID: 31792128 DOI: 10.2967/jnumed.118.220004] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Accepted: 06/18/2019] [Indexed: 12/20/2022] Open
Abstract
The first reporter systems were developed in the early 1980s and were based on measuring the activity of an enzyme-as a surrogate measure of promoter-driven transcriptional activity-which is now known as a reporter gene system. The initial objective and application of reporter techniques was to analyze the activity of a specific promoter (namely, the expression of a gene that is under the regulation of the specific promoter that is linked to the reporter gene). This system allows visualization of specific promoter activity with great sensitivity. In general, there are 2 classes of reporter systems: constitutively expressed (always-on) reporter constructs used for cell tracking, and inducible reporter systems sensitive to endogenous signaling molecules and transcription factors that characterize specific tissues, tumors, or signaling pathways.This review traces the development of different reporter systems, using fluorescent and bioluminescent proteins as well as radionuclide-based reporter systems. The development and application of radionuclide-based reporter systems is the focus of this review. The question at the end of the review is whether the "promise" of reporter gene imaging has been realized. What is required for moving forward with radionuclide-based reporter systems, and what is required for successful translation to clinical applications?
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Affiliation(s)
- Inna Serganova
- Department of Neurology, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Ronald G Blasberg
- Department of Neurology, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, New York .,Department of Radiology, Memorial Hospital, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, New York; and.,Molecular Pharmacology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, New York
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Galldiks N, Lohmann P, Werner JM, Ceccon G, Fink GR, Langen KJ. Molecular imaging and advanced MRI findings following immunotherapy in patients with brain tumors. Expert Rev Anticancer Ther 2019; 20:9-15. [PMID: 31842635 DOI: 10.1080/14737140.2020.1705788] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Introduction: Currently, immunotherapy using vaccination strategies or oncolytic virus approaches, cell-based immunotherapy, and the blockade of immune checkpoints are under evaluation in patients with brain cancer. Here we summarize clinically significant imaging findings such as treatment-related changes detected by advanced neuroimaging techniques following the most suitable immunotherapy options currently used in neuro-oncology. We, furthermore, provide an overview of how these advanced imaging techniques may help to overcome shortcomings of standard MRI in the assessment and follow-up of patients with brain cancer.Areas covered: The current literature on neuroimaging for immunotherapy in the field of brain tumors, with a focus on gliomas and brain metastases is summarized.Expert commentary: Data suggest that imaging parameters primarily derived from amino acid PET, diffusion- and perfusion-weighted MRI, or MR spectroscopy are particularly helpful for the evaluation of treatment response and provide valuable information for the differentiation of treatment-induced changes from actual brain tumor progression following various immunotherapy approaches.
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Affiliation(s)
- Norbert Galldiks
- Department of Neurology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany.,Institute of Neuroscience and Medicine (INM-3, -4), Research Center Juelich, Jülich, Germany.,Center of Integrated Oncology (CIO), Universities of Aachen, Bonn, Cologne, and Duesseldorf, Germany
| | - Philipp Lohmann
- Institute of Neuroscience and Medicine (INM-3, -4), Research Center Juelich, Jülich, Germany
| | - Jan-Michael Werner
- Department of Neurology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany
| | - Garry Ceccon
- Department of Neurology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany
| | - Gereon R Fink
- Department of Neurology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany.,Institute of Neuroscience and Medicine (INM-3, -4), Research Center Juelich, Jülich, Germany
| | - Karl-Josef Langen
- Institute of Neuroscience and Medicine (INM-3, -4), Research Center Juelich, Jülich, Germany.,Center of Integrated Oncology (CIO), Universities of Aachen, Bonn, Cologne, and Duesseldorf, Germany.,Department of Nuclear Medicine, University Hospital RWTH Aachen, Aachen, Germany
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Kasten BB, Udayakumar N, Leavenworth JW, Wu AM, Lapi SE, McConathy JE, Sorace AG, Bag AK, Markert JM, Warram JM. Current and Future Imaging Methods for Evaluating Response to Immunotherapy in Neuro-Oncology. Theranostics 2019; 9:5085-5104. [PMID: 31410203 PMCID: PMC6691392 DOI: 10.7150/thno.34415] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Accepted: 04/20/2019] [Indexed: 12/28/2022] Open
Abstract
Imaging plays a central role in evaluating responses to therapy in neuro-oncology patients. The advancing clinical use of immunotherapies has demonstrated that treatment-related inflammatory responses mimic tumor growth via conventional imaging, thus spurring the development of new imaging approaches to adequately distinguish between pseudoprogression and progressive disease. To this end, an increasing number of advanced imaging techniques are being evaluated in preclinical and clinical studies. These novel molecular imaging approaches will serve to complement conventional response assessments during immunotherapy. The goal of these techniques is to provide definitive metrics of tumor response at earlier time points to inform treatment decisions, which has the potential to improve patient outcomes. This review summarizes the available immunotherapy regimens, clinical response criteria, current state-of-the-art imaging approaches, and groundbreaking strategies for future implementation to evaluate the anti-tumor and immune responses to immunotherapy in neuro-oncology applications.
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Affiliation(s)
- Benjamin B. Kasten
- Department of Neurosurgery, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Neha Udayakumar
- School of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Jianmei W. Leavenworth
- Department of Neurosurgery, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Anna M. Wu
- Crump Institute for Molecular Imaging, Department of Molecular and Medical Pharmacology, David Geffen School of Medicine at University of California Los Angeles, Los Angeles, CA, United States
| | - Suzanne E. Lapi
- Department of Radiology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Jonathan E. McConathy
- Department of Radiology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Anna G. Sorace
- Department of Radiology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Asim K. Bag
- Department of Diagnostic Imaging, St. Jude Children's Research Hospital, Memphis, TN, United States
| | - James M. Markert
- Department of Neurosurgery, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Jason M. Warram
- Department of Otolaryngology, University of Alabama at Birmingham, Birmingham, AL, United States
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Li M, Wang Y, Liu M, Lan X. Multimodality reporter gene imaging: Construction strategies and application. Theranostics 2018; 8:2954-2973. [PMID: 29896296 PMCID: PMC5996353 DOI: 10.7150/thno.24108] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Accepted: 03/06/2018] [Indexed: 12/11/2022] Open
Abstract
Molecular imaging has played an important role in the noninvasive exploration of multiple biological processes. Reporter gene imaging is a key part of molecular imaging. By combining with a reporter probe, a reporter protein can induce the accumulation of specific signals that are detectable by an imaging device to provide indirect information of reporter gene expression in living subjects. There are many types of reporter genes and each corresponding imaging technique has its own advantages and drawbacks. Fused reporter genes or single reporter genes with products detectable by multiple imaging modalities can compensate for the disadvantages and potentiate the advantages of each modality. Reporter gene multimodality imaging could be applied to trace implanted cells, monitor gene therapy, assess endogenous molecular events, screen drugs, etc. Although several types of multimodality imaging apparatus and multimodality reporter genes are available, more sophisticated detectors and multimodality reporter gene systems are needed.
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Affiliation(s)
- Mengting Li
- Department of Nuclear Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology
- Hubei Province Key Laboratory of Molecular Imaging
| | - Yichun Wang
- Department of Nuclear Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology
- Hubei Province Key Laboratory of Molecular Imaging
| | - Mei Liu
- Department of Nuclear Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology
- Hubei Province Key Laboratory of Molecular Imaging
| | - Xiaoli Lan
- Department of Nuclear Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology
- Hubei Province Key Laboratory of Molecular Imaging
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Injected Human Muscle Precursor Cells Overexpressing PGC-1 α Enhance Functional Muscle Regeneration after Trauma. Stem Cells Int 2018. [PMID: 29531537 PMCID: PMC5827889 DOI: 10.1155/2018/4658503] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
While many groups demonstrated new muscle tissue formation after muscle precursor cell (MPC) injection, the capacity of these cells to heal muscle damage, for example, sphincter in stress urinary incontinence, in long-term is still limited. Therefore, the first goal of our project was to optimize the functional regenerative potential of hMPC by genetic modification to overexpress human peroxisome proliferator-activated receptor gamma coactivator 1-alpha (hPGC-1α), key regulator of exercise-mediated adaptation. Moreover, we aimed at establishing a feasible methodology for noninvasive PET visualization of implanted cells and their microenvironment in muscle crush injury model. PGC-1α-bioengineered muscles showed enhanced marker expression for myogenesis (α-actinin, MyHC, and Desmin), vascularization (VEGF), neuronal (ACHE), and mitochondrial (COXIV) activity. Consistently, use of hPGC-1α_hMPCs produced significantly increased contractile force one to three weeks postinjury. PET imaging showed distinct differences in radiotracer signals ([18F]Fallypride and [11C]Raclopride (both targeting dopamine 2 receptors (D2R)) and [64Cu]NODAGA-RGD (targeting neovascularization)) between GFP_hMPCs and hD2R_hPGC-1α_hMPCs. After muscle harvesting, inflammation levels were in parallel to radiotracer uptake amount, with significantly lower uptake in hPGC-1α overexpressing samples. In summary, we facilitated early functional muscle tissue regeneration, introducing a novel approach to improve skeletal muscle regeneration. Besides successful tracking of hMPCs in muscle crush injuries, we showed that in high-inflammation areas, the specificity of radioligands might be significantly reduced, addressing a possible bottleneck of neovascularization PET imaging.
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Wu ZJ, Tang FR, Ma ZW, Peng XC, Xiang Y, Zhang Y, Kang J, Ji J, Liu XQ, Wang XW, Xin HW, Ren BX. Oncolytic Viruses for Tumor Precision Imaging and Radiotherapy. Hum Gene Ther 2018; 29:204-222. [PMID: 29179583 DOI: 10.1089/hum.2017.189] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
In 2003 in China, Peng et al. invented the recombinant adenovirus expressing p53 (Gendicine) for clinical tumor virotherapy. This was the first clinically approved gene therapy and tumor virotherapy drug in the world. An oncolytic herpes simplex virus expressing granulocyte-macrophage colony-stimulating factor (Talimogene laherparepvec) was approved for melanoma treatment in the United States in 2015. Since then, oncolytic viruses have been attracting more and more attention in the field of oncology, and may become novel significant modalities of tumor precision imaging and radiotherapy after further improvement. Oncolytic viruses carrying reporter genes can replicate and express genes of interest selectively in tumor cells, thus improving in vivo noninvasive precision molecular imaging and radiotherapy. Here, the latest developments and molecular mechanisms of tumor imaging and radiotherapy using oncolytic viruses are reviewed, and perspectives are given for further research. Various types of tumors are discussed, and special attention is paid to gastrointestinal tumors.
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Affiliation(s)
- Zi J Wu
- 1 Laboratory of Oncology, Center for Molecular Medicine, Yangtze University , Jingzhou, China .,2 Department of Medical Imaging, School of Medicine, Yangtze University , Jingzhou, China .,3 The Second School of Clinical Medicine, Yangtze University , Jingzhou, China
| | - Feng R Tang
- 4 Radiation Physiology Laboratory, Singapore Nuclear Research and Safety Initiative, National University of Singapore , Create Tower, Singapore
| | - Zhao-Wu Ma
- 1 Laboratory of Oncology, Center for Molecular Medicine, Yangtze University , Jingzhou, China
| | - Xiao-Chun Peng
- 1 Laboratory of Oncology, Center for Molecular Medicine, Yangtze University , Jingzhou, China
| | - Ying Xiang
- 1 Laboratory of Oncology, Center for Molecular Medicine, Yangtze University , Jingzhou, China
| | - Yanling Zhang
- 5 Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine , Guangzhou, China .,6 School of Biotechnology, Southern Medical University , Guangzhou, China
| | - Jingbo Kang
- 7 The Navy General Hospital Tumor Diagnosis and Treatment Center , Beijing, China
| | - Jiafu Ji
- 8 Department of Gastrointestinal Surgery, Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Peking University Cancer Hospital and Institute , Beijing, China
| | - Xiao Q Liu
- 1 Laboratory of Oncology, Center for Molecular Medicine, Yangtze University , Jingzhou, China .,2 Department of Medical Imaging, School of Medicine, Yangtze University , Jingzhou, China .,3 The Second School of Clinical Medicine, Yangtze University , Jingzhou, China
| | - Xian-Wang Wang
- 1 Laboratory of Oncology, Center for Molecular Medicine, Yangtze University , Jingzhou, China
| | - Hong-Wu Xin
- 1 Laboratory of Oncology, Center for Molecular Medicine, Yangtze University , Jingzhou, China
| | - Bo X Ren
- 2 Department of Medical Imaging, School of Medicine, Yangtze University , Jingzhou, China .,3 The Second School of Clinical Medicine, Yangtze University , Jingzhou, China
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Lutz S, Williams E, Muthu P. Engineering Therapeutic Enzymes. DIRECTED ENZYME EVOLUTION: ADVANCES AND APPLICATIONS 2017:17-67. [DOI: 10.1007/978-3-319-50413-1_2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
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12
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Haralampieva D, Betzel T, Dinulovic I, Salemi S, Stoelting M, Krämer SD, Schibli R, Sulser T, Handschin C, Eberli D, Ametamey SM. Noninvasive PET Imaging and Tracking of Engineered Human Muscle Precursor Cells for Skeletal Muscle Tissue Engineering. J Nucl Med 2016; 57:1467-73. [PMID: 27199355 DOI: 10.2967/jnumed.115.170548] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Accepted: 02/08/2016] [Indexed: 01/12/2023] Open
Abstract
UNLABELLED Transplantation of human muscle precursor cells (hMPCs) is envisioned for the treatment of various muscle diseases. However, a feasible noninvasive tool to monitor cell survival, migration, and integration into the host tissue is still missing. METHODS In this study, we designed an adenoviral delivery system to genetically modify hMPCs to express a signaling-deficient form of human dopamine D2 receptor (hD2R). The gene expression levels of the receptor were evaluated by reverse transcriptase polymerase chain reaction, and infection efficiency was evaluated by fluorescent microscopy. The viability, proliferation, and differentiation capacity of the transduced cells, as well as their myogenic phenotype, were determined by flow cytometry analysis and fluorescent microscopy. (18)F-fallypride and (18)F-fluoromisonidazole, two well-established PET radioligands, were assessed for their potential to image engineered hMPCs in a mouse model and their uptakes were evaluated at different time points after cell inoculation in vivo. Biodistribution studies, autoradiography, and PET experiments were performed to determine the extent of signal specificity. To address feasibility for tracking hMPCs in an in vivo model, the safety of the adenoviral gene delivery was evaluated. Finally, the harvested tissues were histologically examined to determine whether survival of the transplanted cells was sustained at different time points. RESULTS Adenoviral gene delivery was shown to be safe, with no detrimental effects on the primary human cells. The viability, proliferation, and differentiation capacity of the transduced cells were confirmed, and flow cytometry analysis and fluorescent microscopy showed that their myogenic phenotype was sustained. (18)F-fallypride and (18)F-fluoromisonidazole were successfully synthesized. Specific binding of (18)F-fallypride to hD2R hMPCs was demonstrated in vitro and in vivo. Furthermore, the (18)F-fluoromisonidazole signal was high at the early stages. Finally, sustained survival of the transplanted cells at different time points was confirmed histologically, with formation of muscle tissue at the site of injection. CONCLUSION Our proposed use of a signaling-deficient hD2R as a potent reporter for in vivo hMPC PET tracking by (18)F-fallypride is a significant step toward potential noninvasive tracking of hD2R hMPCs and bioengineered muscle tissues in the clinic.
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Affiliation(s)
- Deana Haralampieva
- Institute of Pharmaceutical Sciences, ETH Zurich, Zurich, Switzerland Laboratory for Tissue Engineering and Stem Cell Therapy, Department of Urology, University Hospital Zurich, University of Zurich, Zurich, Switzerland Zurich Center for Integrative Human Physiology, Zurich, Switzerland; and
| | - Thomas Betzel
- Institute of Pharmaceutical Sciences, ETH Zurich, Zurich, Switzerland
| | - Ivana Dinulovic
- Focal Area of Growth and Development, Biozentrum, University of Basel, Basel, Switzerland
| | - Souzan Salemi
- Laboratory for Tissue Engineering and Stem Cell Therapy, Department of Urology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Meline Stoelting
- Laboratory for Tissue Engineering and Stem Cell Therapy, Department of Urology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Stefanie D Krämer
- Institute of Pharmaceutical Sciences, ETH Zurich, Zurich, Switzerland
| | - Roger Schibli
- Institute of Pharmaceutical Sciences, ETH Zurich, Zurich, Switzerland
| | - Tullio Sulser
- Laboratory for Tissue Engineering and Stem Cell Therapy, Department of Urology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Christoph Handschin
- Focal Area of Growth and Development, Biozentrum, University of Basel, Basel, Switzerland
| | - Daniel Eberli
- Laboratory for Tissue Engineering and Stem Cell Therapy, Department of Urology, University Hospital Zurich, University of Zurich, Zurich, Switzerland Zurich Center for Integrative Human Physiology, Zurich, Switzerland; and
| | - Simon M Ametamey
- Institute of Pharmaceutical Sciences, ETH Zurich, Zurich, Switzerland Zurich Center for Integrative Human Physiology, Zurich, Switzerland; and
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Sanches PG, Peters S, Rossin R, Kaijzel EL, Que I, Löwik CWGM, Grüll H. Bone metastasis imaging with SPECT/CT/MRI: a preclinical toolbox for therapy studies. Bone 2015; 75:62-71. [PMID: 25680341 DOI: 10.1016/j.bone.2015.02.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2014] [Revised: 01/31/2015] [Accepted: 02/03/2015] [Indexed: 12/27/2022]
Abstract
Bone is one of the most common metastatic target sites in breast cancer, with more than 200 thousand new cases of invasive cancer diagnosed in the US alone in 2011. We set out to establish a multimodality imaging platform for bone metastases in small animals as a tool to non-invasively quantify metastasis growth, imaging the ensuing bone lesions and possibly the response to treatment. To this end, a mouse model of osteolytic metastatic bone tumors was characterized with SPECT/CT and MRI over time. A cell line capable of forming bone metastases, MDA-MB-231, was genetically modified to stably express the reporter gene herpes simplex virus-1 thymidine kinase (hsv-1 tk). The intracellular accumulation of the radiolabeled tracer [(123)I]FIAU promoted by HSV-1 TK specifically pinpoints the location of tumor cells which can be imaged in vivo by SPECT. First, a study using tumors implanted subcutaneously was performed. The SPECT/MRI overlays and the ex vivo γ-counting showed a linear correlation in terms of %ID/cm(3) (R(2)=0.93) and %ID/g (R(2)=0.77), respectively. Then, bone metastasis growth was imaged weekly by SPECT/CT and T2-weighted MRI over a maximum of 40 days post-intracardiac injection of tumor cells. The first activity spots detectable with SPECT, around day 20 post-cell injection, were smaller than 2mm(3) and not yet visible by MRI and increased in volume and in %ID over the weeks. Osteolytic bone lesions were visible by CT (in vivo) and μCT (ex vivo). The SPECT/MRI overlays also showed a linear correlation in terms of %ID/cm(3) (R(2)=0.86). In conclusion, a new multimodality imaging platform has been established that non-invasively combines images of active tumor areas (SPECT), tumor volume (MRI) and the corresponding bone lesions (CT and μCT). To our knowledge this is the first report where the combination of soft tissue information from MRI, bone lesions by CT, and reporter gene imaging by SPECT is used to non-invasively follow metastatic bone lesions.
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Affiliation(s)
- Pedro Gomes Sanches
- Biomedical NMR, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands
| | - Steffie Peters
- Biomedical NMR, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands
| | - Raffaella Rossin
- Department of Oncology Solutions, Philips Research Eindhoven, The Netherlands
| | - Eric L Kaijzel
- Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands
| | - Ivo Que
- Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands
| | - Clemens W G M Löwik
- Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands
| | - Holger Grüll
- Biomedical NMR, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands; Department of Oncology Solutions, Philips Research Eindhoven, The Netherlands.
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14
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Muthu P, Chen HX, Lutz S. Redesigning human 2'-deoxycytidine kinase enantioselectivity for L-nucleoside analogues as reporters in positron emission tomography. ACS Chem Biol 2014; 9:2326-33. [PMID: 25079348 PMCID: PMC4201336 DOI: 10.1021/cb500463f] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
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Recent advances in
nuclear medicine have allowed for positron emission
tomography (PET) to track transgenes in cell-based therapies using
PET reporter gene/probe pairs. A promising example for such reporter
gene/probe pairs are engineered nucleoside kinases that effectively
phosphorylate isotopically labeled nucleoside analogues. Upon expression
in target cells, the kinase facilitates the intracellular accumulation
of radionuclide monophosphate, which can be detected by PET imaging.
We have employed computational design for the semi-rational engineering
of human 2′-deoxycytidine kinase to create a reporter gene
with selectivity for l-nucleosides including l-thymidine
and 1-(2′-fluoro-5-methyl-β-l-arabinofuranosyl)
uracil. Our design strategy relied on a combination of preexisting
data from kinetic and structural studies of native kinases, as well
as two small, focused libraries of kinase variants to generate an in silico model for assessing the effects of single amino
acid changes on favorable activation of l-nucleosides over
their corresponding d-enantiomers. The approach identified
multiple amino acid positions distal to the active site that conferred
desired l-enantioselectivity. Recombination of individual
amino acid substitutions yielded orthogonal kinase variants with significantly
improved catalytic performance for unnatural l-nucleosides
but reduced activity for natural d-nucleosides.
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Affiliation(s)
- Pravin Muthu
- Department of Chemistry, Emory University, 1515 Dickey
Drive, Atlanta, Georgia 30322, United States
| | - Hannah X. Chen
- Department of Chemistry, Emory University, 1515 Dickey
Drive, Atlanta, Georgia 30322, United States
| | - Stefan Lutz
- Department of Chemistry, Emory University, 1515 Dickey
Drive, Atlanta, Georgia 30322, United States
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15
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Okemoto K, Wagner B, Meisen H, Haseley A, Kaur B, Chiocca EA. STAT3 activation promotes oncolytic HSV1 replication in glioma cells. PLoS One 2013; 8:e71932. [PMID: 23936533 PMCID: PMC3732216 DOI: 10.1371/journal.pone.0071932] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2013] [Accepted: 07/04/2013] [Indexed: 12/05/2022] Open
Abstract
Recent studies report that STAT3 signaling is a master regulator of mesenchymal transformation of gliomas and that STAT3 modulated genes are highly expressed in the mesenchymal transcriptome of gliomas. A currently studied experimental treatment for gliomas consists of intratumoral injection of oncolytic viruses (OV), such as oncolytic herpes simplex virus type 1 (oHSV). We have described one particular oHSV (rQNestin34.5) that exhibits potent anti-glioma activity in animal models. Here, we hypothesized that alterations in STAT3 signaling in glioma cells may affect the replicative ability of rQNestin34.5. In fact, human U251 glioma cells engineered to either over-express STAT3 or with genetic down-regulation of STAT3 supported oHSV replication to a significantly higher or lesser degree, respectively, when compared to controls. Administration of pharmacologic agents that increase STAT3 phosphorylation/activation (Valproic Acid) or increase STAT3 levels (Interleukin 6) also significantly enhanced oHSV replication. Instead, administration of inhibitors of STAT3 phosphorylation/activation (LLL12) significantly reduced oHSV replication. STAT3 led to a reduction in interferon signaling in oHSV infected cells and inhibition of interferon signaling abolished the effect of STAT3 on oHSV replication. These data thus indicate that STAT3 signaling in malignant gliomas enhances oHSV replication, likely by inhibiting the interferon response in infected glioma cells, thus suggesting avenues for possible potentiation of oncolytic virotherapy.
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Affiliation(s)
- Kazuo Okemoto
- Dardinger Center for Neuro-Oncology and Neurosciences, Department of Neurological Surgery, James Cancer Hospital/Solove Research Institute/Comprehensive Cancer Center and Wexner Medical Center, the Ohio State University, Columbus, Ohio, United States of America
| | - Benjamin Wagner
- Dardinger Center for Neuro-Oncology and Neurosciences, Department of Neurological Surgery, James Cancer Hospital/Solove Research Institute/Comprehensive Cancer Center and Wexner Medical Center, the Ohio State University, Columbus, Ohio, United States of America
| | - Hans Meisen
- Dardinger Center for Neuro-Oncology and Neurosciences, Department of Neurological Surgery, James Cancer Hospital/Solove Research Institute/Comprehensive Cancer Center and Wexner Medical Center, the Ohio State University, Columbus, Ohio, United States of America
| | - Amy Haseley
- Dardinger Center for Neuro-Oncology and Neurosciences, Department of Neurological Surgery, James Cancer Hospital/Solove Research Institute/Comprehensive Cancer Center and Wexner Medical Center, the Ohio State University, Columbus, Ohio, United States of America
| | - Balveen Kaur
- Dardinger Center for Neuro-Oncology and Neurosciences, Department of Neurological Surgery, James Cancer Hospital/Solove Research Institute/Comprehensive Cancer Center and Wexner Medical Center, the Ohio State University, Columbus, Ohio, United States of America
| | - Ennio Antonio Chiocca
- Dardinger Center for Neuro-Oncology and Neurosciences, Department of Neurological Surgery, James Cancer Hospital/Solove Research Institute/Comprehensive Cancer Center and Wexner Medical Center, the Ohio State University, Columbus, Ohio, United States of America
- Harvey Cushing Neuro-Oncology Laboratories, Department of Neurosurgery, Institute for the Neurosciences at the Brigham, Brigham and Women’s/Faulkner Hospital and Center for Neuro-Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts, United States of America
- * E-mail:
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16
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Brader P, Serganova I, Blasberg RG. Noninvasive Molecular Imaging Using Reporter Genes. J Nucl Med 2013; 54:167-72. [DOI: 10.2967/jnumed.111.099788] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
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17
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Yaghoubi SS, Campbell DO, Radu CG, Czernin J. Positron emission tomography reporter genes and reporter probes: gene and cell therapy applications. Am J Cancer Res 2012; 2:374-91. [PMID: 22509201 PMCID: PMC3326723 DOI: 10.7150/thno.3677] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2011] [Accepted: 02/09/2012] [Indexed: 12/22/2022] Open
Abstract
Positron emission tomography (PET) imaging reporter genes (IRGs) and PET reporter probes (PRPs) are amongst the most valuable tools for gene and cell therapy. PET IRGs/PRPs can be used to non-invasively monitor all aspects of the kinetics of therapeutic transgenes and cells in all types of living mammals. This technology is generalizable and can allow long-term kinetics monitoring. In gene therapy, PET IRGs/PRPs can be used for whole-body imaging of therapeutic transgene expression, monitoring variations in the magnitude of transgene expression over time. In cell or cellular gene therapy, PET IRGs/PRPs can be used for whole-body monitoring of therapeutic cell locations, quantity at all locations, survival and proliferation over time and also possibly changes in characteristics or function over time. In this review, we have classified PET IRGs/PRPs into two groups based on the source from which they were derived: human or non-human. This classification addresses the important concern of potential immunogenicity in humans, which is important for expansion of PET IRG imaging in clinical trials. We have then discussed the application of this technology in gene/cell therapy and described its use in these fields, including a summary of using PET IRGs/PRPs in gene and cell therapy clinical trials. This review concludes with a discussion of the future direction of PET IRGs/PRPs and recommends cell and gene therapists collaborate with molecular imaging experts early in their investigations to choose a PET IRG/PRP system suitable for progression into clinical trials.
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18
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Rojas JJ, Thorne SH. Theranostic potential of oncolytic vaccinia virus. Theranostics 2012; 2:363-73. [PMID: 22509200 PMCID: PMC3326721 DOI: 10.7150/thno.3724] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2011] [Accepted: 01/18/2012] [Indexed: 11/17/2022] Open
Abstract
Biological cancer therapies, such as oncolytic, or replication-selective viruses have advantages over traditional therapeutics as they can employ multiple different mechanisms to target and destroy cancers (including direct cell lysis, immune activation and vascular collapse). This has led to their rapid recent clinical development. However this also makes their pre-clinical and clinical study complex, as many parameters may affect their therapeutic potential and so defining reason for treatment failure or approaches that might enhance their therapeutic activity can be complicated. The ability to non-invasively image viral gene expression in vivo both in pre-clinical models and during clinical testing will considerably enhance the speed of oncolytic virus development as well as increasing the level and type of useful data produced from these studies. Further, subsequent to future clinical approval, imaging of reporter gene expression might be used to evaluate the likelihood of response to oncolytic viral therapy prior to changes in tumor burden. Here different reporter genes used in conjunction with oncolytic viral therapy are described, along with the imaging modalities used to measure their expression, while their applications both in pre-clinical and clinical testing are discussed. Possible future applications for reporter gene expression from oncolytic viruses in the phenotyping of tumors and the personalizing of treatment regimens are also discussed.
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19
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Roelcke U. Imaging brain tumors with PET, SPECT, and ultrasonography. HANDBOOK OF CLINICAL NEUROLOGY 2012; 104:135-142. [PMID: 22230440 DOI: 10.1016/b978-0-444-52138-5.00010-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Affiliation(s)
- Ulrich Roelcke
- Department of Neurology, Cantonal Hospital, Aarau, Switzerland.
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20
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White E, Bienemann A, Megraw L, Bunnun C, Gill S. Evaluation and optimization of the administration of a selectively replicating herpes simplex viral vector to the brain by convection-enhanced delivery. Cancer Gene Ther 2011; 18:358-69. [PMID: 21372854 DOI: 10.1038/cgt.2011.2] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The direct intraparenchymal administration of oncolytic viral vectors by convection-enhanced delivery (CED) represents a promising new treatment strategy for malignant gliomas. However, there is no evidence to suggest that oncolytic viruses as large as herpes simplex virus-1 (HSV-1) can be administered by CED, as this has not been systematically examined in an animal model. In this study, the administration of a herpes simplex viral vector, HSV1, has been evaluated in detail in the gray and white matter of both rat and pig models, using high flow-rate infusions, co-infusing heparin or preinfusing the tissue with an isotonic albumin solution. Rat HSV-1 infusions at both slow (0.5 μl min(-1)) and high infusion rates (2.5 μl min(-1)) led to extensive tissue damage and negligible cell transduction. Co-infusion with heparin led to extensive hemorrhage. Preinfusion of tissue with an isotonic albumin solution facilitated widespread vector distribution and cell transduction in white matter only. Using this approach in pig brain led to widespread vector distribution with extensive transduction of astrocytes and activated microglia. In rat brain, enhanced green fluorescent protein expression peaked 48 h after vector administration and was associated with a vigorous immune response. These findings indicate that direct infusions of HSV-1-based viral vectors into the brain lead to minimal vector distribution, negligible cell transduction and extensive damage. Tissue preinfusion with an isotonic solution prior to vector administration represents an effective technique for achieving widespread HSV-1 distribution.
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Affiliation(s)
- E White
- Department of Neurosurgery, Frenchay Hospital, Bristol, UK
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21
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Grandi P, Peruzzi P, Reinhart B, Cohen JB, Chiocca EA, Glorioso JC. Design and application of oncolytic HSV vectors for glioblastoma therapy. Expert Rev Neurother 2009; 9:505-17. [PMID: 19344302 DOI: 10.1586/ern.09.9] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Glioblastoma multiforme is one of the most common human brain tumors. The tumor is generally highly infiltrative, making it extremely difficult to treat by surgical resection or radiotherapy. This feature contributes to recurrence and a very poor prognosis. Few anticancer drugs have been shown to alter rapid tumor growth and none are ultimately effective. Oncolytic vectors have been employed as a treatment alternative based on the ability to tailor virus replication to tumor cells. The human neurotropic herpes simplex virus (HSV) is especially attractive for development of oncolytic vectors (oHSV) because this virus is highly infectious, replicates rapidly and can be readily modified to achieve vector attenuation in normal brain tissue. Tumor specificity can be achieved by deleting viral genes that are only required for virus replication in normal cells and permit mutant virus replication selectively in tumor cells. The anti-tumor activity of oHSV can be enhanced by arming the vector with genes that either activate chemotherapeutic drugs within the tumor tissue or promote anti-tumor immunity. In this review, we describe current designs of oHSV and the experience thus far with their potential utility for glioblastoma therapy. In addition, we discuss the impediments to vector effectiveness and describe our view of future developments in vector improvement.
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Affiliation(s)
- Paola Grandi
- Department of Neurological Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA.
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22
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Phase I study of noninvasive imaging of adenovirus-mediated gene expression in the human prostate. Mol Ther 2008; 16:1761-9. [PMID: 18714306 DOI: 10.1038/mt.2008.172] [Citation(s) in RCA: 107] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
To monitor noninvasively potentially therapeutic adenoviruses for cancer, we have developed a methodology based on the sodium iodide symporter (NIS). Men with clinically localized prostate cancer were administered an intraprostatic injection of a replication-competent adenovirus, Ad5-yCD/utTK(SR39)rep-hNIS, armed with two suicide genes and the NIS gene. NIS gene expression (GE) was imaged noninvasively by uptake of Na(99 m)TcO(4) in infected cells using single photon emission-computed tomography (SPECT). The investigational therapy was safe with 98% of the adverse events being grade 1 or 2. GE was detected in the prostate in seven of nine (78%) patients at 1 x 10(12) virus particles (vp) but not at 1 x 10(11) vp. Volume and total amount of GE was quantified by SPECT. Following injection of 1 x 10(12) vp in 1 cm(3), GE volume (GEV) increased to a mean of 6.6 cm(3), representing, on average, 18% of the total prostate volume. GEV and intensity peaked 1-2 days after the adenovirus injection and was detectable in the prostate up to 7 days. Whole-body imaging demonstrated intraprostatic gene expression, and there was no evidence of extraprostatic dissemination of the adenovirus by SPECT imaging. The results demonstrate that noninvasive imaging of adenovirus-mediated gene therapy in humans is feasible and safe.
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23
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Massoud TF, Singh A, Gambhir SS. Noninvasive molecular neuroimaging using reporter genes: part II, experimental, current, and future applications. AJNR Am J Neuroradiol 2008; 29:409-18. [PMID: 18272565 DOI: 10.3174/ajnr.a0863] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
SUMMARY In this second article, we review the various strategies and applications that make use of reporter genes for molecular imaging of the brain in living subjects. These approaches are emerging as valuable tools for monitoring gene expression in diverse applications in laboratory animals, including the study of gene-targeted and trafficking cells, gene therapies, transgenic animals, and more complex molecular interactions within the central nervous system. Further development of more sensitive and selective reporters, combined with improvements in detection technology, will consolidate the position of in vivo reporter gene imaging as a versatile technique for greater understanding of intracellular biologic processes and underlying molecular neuropathology and will potentially establish a future role in the clinical management of patients with neurologic diseases.
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Affiliation(s)
- T F Massoud
- Department of Radiology, Section of Neuroradiology, University of Cambridge School of Clinical Medicine, Addenbrooke's Hospital, Cambridge, UK.
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24
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Russell SJ, Peng KW. Viruses as anticancer drugs. Trends Pharmacol Sci 2007; 28:326-33. [PMID: 17573126 PMCID: PMC3125087 DOI: 10.1016/j.tips.2007.05.005] [Citation(s) in RCA: 137] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2007] [Revised: 04/11/2007] [Accepted: 05/25/2007] [Indexed: 01/14/2023]
Abstract
Oncolytic viruses are being developed as anticancer drugs. They propagate selectively in tumor tissue and destroy it without causing excessive damage to normal non-cancerous tissues. When used as drugs, they must meet stringent criteria for safety and efficacy and be amenable to pharmacological study in human subjects. Specificity for neoplastic tissue is the key to safety, and this goal can be achieved through a variety of ingenious virus-engineering strategies. Antiviral immunity remains a significant barrier to the clinical efficacy of oncolytic viruses but this is being addressed by using novel immune-evasive delivery strategies and immunosuppressive drugs. Noninvasive pharmacokinetic monitoring is facilitated by engineering marker genes into the viral genome. Clinical data on the pharmacokinetics of oncolytic viruses will be the key to accelerating their development and approval as effective anticancer drugs. This review introduces concepts relevant to the use of viruses as anticancer drugs, emphasizing targeting mechanisms as well as safety and efficacy issues that are currently limiting their clinical success.
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Affiliation(s)
- Stephen J Russell
- Molecular Medicine Program, Mayo Clinic College of Medicine, 200 First Street SW, Rochester, MN 55905, USA.
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