1
|
Kyuno D, Qian B, Groß W, Schäfer M, Ryschich E. Endothelium capture-based liver segment imaging using vascular endothelial growth factor receptor 2 in preclinical ex vivo models. BJS Open 2020; 4:332-341. [PMID: 31965760 PMCID: PMC7093791 DOI: 10.1002/bjs5.50253] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Revised: 11/08/2019] [Accepted: 11/20/2019] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Near-infrared (NIR) imaging of liver segments provides substantial information for surgeons performing liver resection. It was hypothesized that ramucirumab, an endothelium-specific antibody approved by the Food and Drug Administration, could be used for liver segment imaging using the endothelium capture principle. METHODS The capture efficacy of anti-vascular endothelial growth factor receptor (VEGFR) 2 monoclonal antibodies (mAbs) and segment imaging were studied in a mouse model. Binding of ramucirumab in human and porcine tissues was studied using immunofluorescence staining. Isolated porcine liver perfusion was used to analyse the labelling and NIR imaging of selected liver segments. RESULTS VEGFR2 is well expressed on the endothelium of the smallest microvascular blood vessels in mouse, porcine and human liver tissues, as well as in human liver tumours. Perfusion of selected segments in the isolated liver model showed high capture of the anti-VEGFR2 (clone 522302) mAb and ramucirumab in mice and pigs respectively. NIR imaging of selected segments was achieved using isolated porcine liver perfusion with IRDye® 800CW-conjugated ramucirumab. CONCLUSION VEGFR2 is well expressed on the smallest microvascular blood vessels and can capture antibodies during single intravascular passages with high efficacy. The ex vivo imaging of a selected segment using endothelial capture of ramucirumab demonstrates the potential of this antibody for intraoperative navigation in liver surgery. Surgical relevance Imaging of liver segments provides substantial information for surgeons when performing liver resection. The antivascular endothelial growth factor receptor (VEGFR) 2 antibody ramucirumab conjugated with near-infrared dye could visualize selected liver segments using an endothelial capture-based approach in an isolated perfusion liver model. The ex vivo imaging of a selected segment using endothelial capture of ramucirumab demonstrates the potential of this anti-VEGFR2 antibody for intraoperative navigation in liver surgery.
Collapse
Affiliation(s)
- D. Kyuno
- Department of General, Visceral and Transplantation SurgeryUniversity Hospital HeidelbergHeidelbergGermany
- Department of Surgery, Surgical Oncology and ScienceSapporo Medical UniversitySapporoJapan
| | - B. Qian
- Department of General, Visceral and Transplantation SurgeryUniversity Hospital HeidelbergHeidelbergGermany
| | - W. Groß
- Department of General, Visceral and Transplantation SurgeryUniversity Hospital HeidelbergHeidelbergGermany
| | - M. Schäfer
- Department of General, Visceral and Transplantation SurgeryUniversity Hospital HeidelbergHeidelbergGermany
| | - E. Ryschich
- Department of General, Visceral and Transplantation SurgeryUniversity Hospital HeidelbergHeidelbergGermany
| |
Collapse
|
2
|
Biswal NC, Fu X, Jagtap JM, Shea MJ, Kumar V, Lords T, Roy R, Schiff R, Joshi A. In vivo longitudinal imaging of RNA interference-induced endocrine therapy resistance in breast cancer. JOURNAL OF BIOPHOTONICS 2020; 13:e201900180. [PMID: 31595691 PMCID: PMC9229172 DOI: 10.1002/jbio.201900180] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Revised: 07/26/2019] [Accepted: 07/29/2019] [Indexed: 05/04/2023]
Abstract
Endocrine therapy resistance in breast cancer is a major obstacle in the treatment of patients with estrogen receptor-positive (ER+) tumors. Herein, we demonstrate the feasibility of longitudinal, noninvasive and semiquantitative in vivo molecular imaging of resistance to three endocrine therapies by using an inducible fluorescence-labeled short hairpin RNA (shRNA) system in orthotopic mice xenograft tumors. We employed a dual fluorescent doxycycline (Dox)-regulated lentiviral inducer system to transfect ER+ MCF7L breast cancer cells, with green fluorescent protein (GFP) expression as a marker of transfection and red fluorescent protein (RFP) expression as a surrogate marker of Dox-induced tumor suppressor phosphatase and tensin homolog deleted on chromosome 10 (PTEN) knockdown. Xenografted MCF7L tumor-bearing nude mice were randomized to therapies comprising estrogen deprivation, tamoxifen or an ER degrader (fulvestrant) and an estrogen-treated control group. Longitudinal imaging was performed by a home-built multispectral imaging system based on a cooled image intensified charge coupled device camera. The GFP signal, which corresponds to number of viable tumor cells, exhibited excellent correlation to caliper-measured tumor size (P << .05). RFP expression was substantially higher in mice exhibiting therapy resistance and strongly and significantly (P < 1e-7) correlated with the tumor size progression for the mice with shRNA-induced PTEN knockdown. PTEN loss was strongly correlated with resistance to estrogen deprivation, tamoxifen and fulvestrant therapies.
Collapse
Affiliation(s)
- Nrusingh C. Biswal
- Division of Molecular Imaging, Department of Radiology, Baylor College of Medicine, Houston, TX 77030, USA
- Department of Radiation Oncology, Rutgers Cancer Institute of New Jersey, New Brunswick, NJ 08901, USA
- Correspondence Nrusingh C. Biswal, Department of Radiation Oncology, University of Maryland, Baltimore, 850. W Baltimore St, MD 21201, USA,
| | - Xiaoyong Fu
- Lester and Sue Smith Breast Center, Baylor College of Medicine, Houston, TX 77030, USA
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Jaidip M. Jagtap
- Departments of Biomedical Engineering and Radiology, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Martin J. Shea
- Lester and Sue Smith Breast Center, Baylor College of Medicine, Houston, TX 77030, USA
| | - Vijetha Kumar
- Lester and Sue Smith Breast Center, Baylor College of Medicine, Houston, TX 77030, USA
| | - Tamika Lords
- Lester and Sue Smith Breast Center, Baylor College of Medicine, Houston, TX 77030, USA
| | - Ronita Roy
- Division of Molecular Imaging, Department of Radiology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Rachel Schiff
- Lester and Sue Smith Breast Center, Baylor College of Medicine, Houston, TX 77030, USA
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX 77030, USA
- Department of Medicine, Baylor College of Medicine, Houston, TX 77030, USA
| | - Amit Joshi
- Division of Molecular Imaging, Department of Radiology, Baylor College of Medicine, Houston, TX 77030, USA
- Departments of Biomedical Engineering and Radiology, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| |
Collapse
|
3
|
Evaluation of drug mechanism and efficacy of a novel anti-angiogenic agent, TTAC-0001, using multi-modality bioimaging in a mouse breast cancer orthotopic model. PLoS One 2018; 13:e0187063. [PMID: 29370209 PMCID: PMC5784895 DOI: 10.1371/journal.pone.0187063] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Accepted: 10/12/2017] [Indexed: 01/04/2023] Open
Abstract
Purpose Targeting of vascular endothelial growth factor receptors (VEGFRs) has potential anti-angiogenic effects because VEGFR-2 is the major signaling regulator of VEGF/VEGFR pathways. We aimed to elucidate the drug mechanism and anti-tumor efficacy of TTAC-0001, a novel, fully human anti-VEGFR-2/KDR monoclonal antibody, in mouse orthotopic breast cancer model using multi-modal bioimaging. Materials and methods We used orthotopic xenograft tumor model in which human breast cancer cells (MDA-MB-231) were injected into the right mammary fat pad of Balb/c nude mice. We investigated its biodistribution using serial fluorescence imaging after injecting fluorescent-labelled-drug and mode of action using Matrigel plug angiogenesis assays. The anti-tumor efficacy of drug was assessed using ultrasonography and bioluminescence imaging. Histopathologic analyses, including hematoxylin and eosin staining and immunohistochemistry with anti-CD31 and anti-Ki-67 antibodies, were performed. Each experiment had four groups: control, bevacizumab 10 mg/kg (BVZ-10 group), TTAC-0001 2 mg/kg (TTAC-2 group), and TTAC-0001 10 mg/kg (TTAC-10 group). Results The TTAC-10 group showed good tumor targeting that lasted for at least 6 days and had a good anti-angiogenic effect with decreased hemoglobin content and fewer CD31-positive cells in the Matrigel plug. Compared with BVZ-10 and TTAC-2 groups, the TTAC-10 group showed the strongest anti-tumor efficacy, inhibiting tumor growth as detected by ultrasonography and bioluminescence imaging. The TTAC-10 group also showed the lowest viable tumor and micro-vessel areas and the lowest Ki-67 index in histopathologic analyses. Conclusion We firstly demonstrated that TTAC-0001 effectively inhibited tumor growth and neovascularization in mouse orthotopic breast cancer model. It may provide a future treatment option for breast cancer.
Collapse
|
4
|
Sorafenib in combination with ionizing radiation has a greater anti-tumour activity in a breast cancer model. Anticancer Drugs 2012; 23:525-33. [DOI: 10.1097/cad.0b013e32834ea5b3] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
5
|
Abstract
Angiogenesis is a fundamental requirement for tumor growth and therefore it is a primary target for anti-cancer therapy. Molecular imaging of angiogenesis may provide novel opportunities for early diagnostic and for image-guided optimization and management of therapeutic regimens. Here we reviewed the advances in targeted imaging of key biomarkers of tumor angiogenesis, integrins and receptors for vascular endothelial growth factor (VEGF). Tracers for targeted imaging of these biomarkers in different imaging modalities are now reasonably well-developed and PET tracers for integrin imaging are currently in clinical trials. Molecular imaging of longitudinal responses to anti-angiogenic therapy in model tumor systems revealed a complex pattern of changes in targeted tracer accumulation in tumor, which reflects drug-induced tumor regression followed by vascular rebound. Further work will define the competitiveness of targeted imaging of key angiogenesis markers for early diagnostic and image-guided therapy.
Collapse
|
6
|
Backer MV, Backer JM. Imaging key biomarkers of tumor angiogenesis. Theranostics 2012; 2:502-15. [PMID: 22737188 PMCID: PMC3364556 DOI: 10.7150/thno.3623] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2011] [Accepted: 01/07/2012] [Indexed: 11/05/2022] Open
Abstract
Angiogenesis is a fundamental requirement for tumor growth and therefore it is a primary target for anti-cancer therapy. Molecular imaging of angiogenesis may provide novel opportunities for early diagnostic and for image-guided optimization and management of therapeutic regimens. Here we reviewed the advances in targeted imaging of key biomarkers of tumor angiogenesis, integrins and receptors for vascular endothelial growth factor (VEGF). Tracers for targeted imaging of these biomarkers in different imaging modalities are now reasonably well-developed and PET tracers for integrin imaging are currently in clinical trials. Molecular imaging of longitudinal responses to anti-angiogenic therapy in model tumor systems revealed a complex pattern of changes in targeted tracer accumulation in tumor, which reflects drug-induced tumor regression followed by vascular rebound. Further work will define the competitiveness of targeted imaging of key angiogenesis markers for early diagnostic and image-guided therapy.
Collapse
|
7
|
Romer T, Leonhardt H, Rothbauer U. Engineering antibodies and proteins for molecular in vivo imaging. Curr Opin Biotechnol 2011; 22:882-7. [DOI: 10.1016/j.copbio.2011.06.007] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2011] [Revised: 06/01/2011] [Accepted: 06/06/2011] [Indexed: 12/31/2022]
|
8
|
Synthesis and evaluation of aryl boronic acids as fluorescent artificial receptors for biological carbohydrates. Bioorg Chem 2011; 40:137-142. [PMID: 22177855 DOI: 10.1016/j.bioorg.2011.11.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2011] [Revised: 11/14/2011] [Accepted: 11/14/2011] [Indexed: 11/20/2022]
Abstract
Carbohydrates in various forms play a vital role in numerous critical biological processes. The detection of such saccharides can give insight into the progression of such diseases such as cancer. Boronic acids react with 1,2 and 1,3 diols of saccharides in non-aqueous or basic aqueous media. Herein, we describe the design, synthesis and evaluation of three bisboronic acid fluorescent probes, each having about ten linear steps in its synthesis. Among these compounds that were evaluated, 9b was shown to selectively label HepG2, liver carcinoma cell line within a concentration range of 0.5-10 μM in comparison to COS-7, a normal fibroblast cell line.
Collapse
|
9
|
Nioka S, Chen Y. Optical tecnology developments in biomedicine: history, current and future. Transl Med UniSa 2011; 1:51-150. [PMID: 23905030 PMCID: PMC3728850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Biomedical optics is a rapidly emerging field for medical imaging and diagnostics. This paper reviews several biomedical optical technologies that have been developed and translated for either clinical or pre-clinical applications. Specifically, we focus on the following technologies: 1) near-infrared spectroscopy and tomography, 2) optical coherence tomography, 3) fluorescence spectroscopy and imaging, and 4) optical molecular imaging. There representative biomedical applications are also discussed here.
Collapse
Affiliation(s)
- Shoko Nioka
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104 USA -
| | - Yu Chen
- Fischell Department of Bioengineering, University of Maryland, College Park, MD 20742 USA -
| |
Collapse
|
10
|
Angst E, Chen M, Mojadidi M, Hines OJ, Reber HA, Eibl G. Bioluminescence imaging of angiogenesis in a murine orthotopic pancreatic cancer model. Mol Imaging Biol 2011; 12:570-5. [PMID: 20376570 PMCID: PMC2917614 DOI: 10.1007/s11307-010-0310-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
PURPOSE Angiogenesis is essential for physiological processes as well as for carcinogenesis. New approaches to cancer therapy include targeting angiogenesis. One target is VEGF-A and its receptor VEGFR2. In this study, we sought to investigate pancreatic cancer angiogenesis in a genetically modified VEGFR2-luc-KI mouse. PROCEDURES Live in vivo bioluminescence imaging of angiogenesis was performed continuously until sacrifice in subcutaneous tumors as well as in orthotopically transplanted tumors. Tumor tissue was immunostained for CD-31 and VEGFR2. RESULTS Peritumoral angiogenesis measured by light emission was detected beginning at week 3 following subcutaneous injection. In the orthotopic model, light emission began at day 4, which likely corresponds to wound healing, and continued throughout the experimental period during tumor growth. Peritumoral CD-31 vessel- and VEGFR2-staining were positive. CONCLUSIONS The VEGFR2-luc-KI mouse is a valuable tool to demonstrate tumor angiogenesis and seems to be suitable to evaluate anti-angiogenic approaches in pancreatic cancer.
Collapse
Affiliation(s)
- Eliane Angst
- Hirshberg Laboratory for Pancreatic Cancer Research, Department of Surgery, UCLA Center for Excellence in Pancreatic Diseases, David Geffen School of Medicine, University of California-Los Angeles, 675 Charles E. Young Drive South, Los Angeles, CA 90095, USA.
| | | | | | | | | | | |
Collapse
|
11
|
Hight MR, Nolting DD, McKinley ET, Lander AD, Wyatt SK, Gonyea M, Zhao P, Manning HC. Multispectral fluorescence imaging to assess pH in biological specimens. JOURNAL OF BIOMEDICAL OPTICS 2011; 16:016007. [PMID: 21280913 PMCID: PMC3041815 DOI: 10.1117/1.3533264] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2010] [Revised: 11/01/2010] [Accepted: 11/17/2010] [Indexed: 05/29/2023]
Abstract
Simple, quantitative assays to measure pH in tissue could improve the study of complicated biological processes and diseases such as cancer. We evaluated multispectral fluorescence imaging (MSFI) to quantify extracellular pH (pHe) in dye-perfused, surgically-resected tumor specimens with commercially available instrumentation. Utilizing a water-soluble organic dye with pH-dependent fluorescence emission (SNARF-4F), we used standard fluorimetry to quantitatively assess the emission properties of the dye as a function of pH. By conducting these studies within the spectroscopic constraints imposed by the appropriate imaging filter set supplied with the imaging system, we determined that correction of the fluorescence emission of deprotonated dye was necessary for accurate determination of pH due to suboptimal excitation. Subsequently, employing a fluorimetry-derived correction factor (CF), MSFI data sets of aqueous dye solutions and tissuelike phantoms could be spectrally unmixed to accurately quantify equilibrium concentrations of protonated (HA) and deprotonated (A-) dye and thus determine solution pH. Finally, we explored the feasibility of MSFI for high-resolution pHe mapping of human colorectal cancer cell-line xenografts. Data presented suggest that MSFI is suitable for quantitative determination of pHe in ex vivo dye-perfused tissue, potentially enabling measurement of pH across a variety of preclinical models of disease.
Collapse
Affiliation(s)
- Matthew R Hight
- Vanderbilt University, Department of Physics, Nashville, Tennessee 37221, USA
| | | | | | | | | | | | | | | |
Collapse
|
12
|
Smith RA, Guleryuz S, Manning HC. Molecular imaging metrics to evaluate response to preclinical therapeutic regimens. FRONT BIOSCI-LANDMRK 2011; 16:393-410. [PMID: 21196177 PMCID: PMC3023459 DOI: 10.2741/3694] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Molecular imaging comprises a range of techniques, spanning not only several imaging modalities but also many disease states and organ sites. While advances in new technology platforms have enabled a deeper understanding of the cellular and molecular basis of malignancy, reliable non-invasive imaging metrics remain an important tool for both diagnostics and patient management. Furthermore, the non- invasive nature of molecular imaging can overcome shortcomings associated with traditional biological approaches and provide valuable information relevant to patient care. Integration of information from multiple imaging techniques has the potential to provide a more comprehensive understanding of specific tumor characteristics, tumor status, and treatment response.
Collapse
Affiliation(s)
- R. Adam Smith
- Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN 37232
| | - Saffet Guleryuz
- Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN 37232
| | - H. Charles Manning
- Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN 37232
- Department of Radiology and Radiological Science, Vanderbilt University Medical Center, Nashville, TN 37232
- Department of Biomedical Engineering, Vanderbilt University, Nashville, TN 37232
- Program in Chemical and Physical Biology, Vanderbilt University Medical Center, Nashville, TN 37232
- Department of Neurosurgery, Vanderbilt University Medical Center, Nashville, TN 37232
- Vanderbilt Ingram Cancer Center, Vanderbilt University Medical Center, Nashville, TN 37232
| |
Collapse
|
13
|
Abstract
The process of angiogenesis, an essential hallmark for tumour development as well as for several inflammatory diseases and physiological phenomena, is of growing interest for diagnosis and therapy in oncology. In the context of biochemical characterisation of key molecules involved in angiogenesis, several targets for imaging and therapy could be identified in the last decade. Optical imaging (OI) relies on the visualisation of near infrared (NIR) light, either its absorption and scattering in tissue (non-enhanced OI) or using fluorescent contrast agents. OI offers excellent signal to noise ratios due to virtually absent background fluorescence in the NIR range and is thus a versatile tool to image specific molecular target structures in vivo. This work intends to provide a survey of the different approaches to imaging of angiogenesis using OI methods in preclinical research as well as first clinical trials. Different imaging modalities as well as various optical contrast agents are briefly discussed.
Collapse
|
14
|
Jiang Y, Wang M. Personalized medicine in oncology: tailoring the right drug to the right patient. Biomark Med 2010; 4:523-33. [PMID: 20701441 DOI: 10.2217/bmm.10.66] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Despite advances in the management of many human cancers over the past few decades, improvements in survival are marginal, and the overall diagnosis and prognosis for cancer patients remain poor. Tailoring therapy to the individual patient has become a promising approach for maximizing efficacy and minimizing drug toxicity. Aided by major technological advances, the field of personalized medicine has become extremely active in the identification of predictive biomarkers that can guide treatment decisions and, ultimately, improve treatment outcomes. Genomics and proteomics have provided a means for molecular profiling that allows tailoring of therapy. Although implementing genomic and proteomic testing into clinical practice is still in its infancy, the rapid development of newer technologies and platforms provides hope for personalized medicine.
Collapse
Affiliation(s)
- Yuqiu Jiang
- Veridex, LLC, a Johnson & Johnson Company, Raritan, NJ, USA
| | | |
Collapse
|
15
|
Kagadis GC, Loudos G, Katsanos K, Langer SG, Nikiforidis GC. In vivosmall animal imaging: Current status and future prospects. Med Phys 2010; 37:6421-42. [DOI: 10.1118/1.3515456] [Citation(s) in RCA: 108] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
|
16
|
Abstract
Background One of the major challenges in cancer therapy is to improve early detection and prevention using novel targeted cancer diagnostics. Detection requests specific recognition. Tumor markers have to be ideally present on the surface of cancer cells. Their targeting with ligands coupled to imaging agents make them visible/detectable. Conclusions Fluorescence imaging is a newly emerging technology which is becoming a complementary medical method for cancer diagnosis. It allows detection with a high spatio-temporal resolution of tumor markers in small animals and in clinical studies. In this review, we focus on the recent outcome of basic studies in the design of new approaches (probes and devices) used to detect tumor cells by fluorescence imaging.
Collapse
|
17
|
BR55: a lipopeptide-based VEGFR2-targeted ultrasound contrast agent for molecular imaging of angiogenesis. Invest Radiol 2010; 45:89-95. [PMID: 20027118 DOI: 10.1097/rli.0b013e3181c5927c] [Citation(s) in RCA: 193] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVES BR55, an ultrasound contrast agent functionalized with a heterodimer peptide targeting the vascular endothelial growth factor receptor 2 (VEGFR2), was evaluated in vitro and in vivo, demonstrating its potential for specific tumor detection. MATERIALS AND METHODS The targeted contrast agent was prepared by incorporation of a biospecific lipopeptide into the microbubble membrane. Experiments were performed in vitro to demonstrate the binding capacities of BR55 microbubbles on immobilized receptor proteins and on various endothelial or transfected cells expressing VEGFR2. The performance of BR55 microbubbles was compared with that of streptavidin-conjugated microbubbles targeted to the same receptor by coupling them to a biotinylated antibody. The specificity of BR55 binding to human and mouse endothelial cells was determined in competition experiments with the free lipopeptide, vascular endothelial growth factor (VEGF), or a VEGFR2-specific antibody. Molecular ultrasound imaging of VEGFR2 was performed in an orthotopic breast tumor model in rats using a nondestructive, contrast-specific imaging mode. RESULTS BR55 was shown to bind specifically to the immobilized recombinant VEGFR2 under flow (dynamic conditions). BR55 accumulation on the target over time was similar to that of microbubbles bearing a specific antibody. BR55 avidly bound to cells expressing VEGFR2, and the pattern of microbubble distribution was correlated with the pattern of receptor expression determined by immunocytochemistry. The binding of targeted microbubbles on cells was competed off by an excess of free lipopeptide, the natural ligand (VEGF) and by a VEGFR2-specific antibody (P < 0.001). Although selected for the human receptor, the VEGFR2-binding lipopeptide was also shown to recognize the rodent receptor. Tumor perfusion was assessed during the vascular phase of BR55, and then the malignant lesion was highlighted by specific accumulation of the targeted microbubbles on tumoral endothelium. The presence of VEGFR2 was confirmed by immunofluorescence staining of tumor cryosections. CONCLUSIONS VEGFR2-targeted ultrasound contrast agents such as BR55 will likely prove useful in human for the early detection of tumors as well as for the assessment of response to specific treatments.
Collapse
|
18
|
Abstract
Multispectral fluorescence imaging (MSFI) is a rapidly growing field with broad applications in both preclinical and clinical settings. Application of this novel technology in small-animal imaging and microscopy produces enhanced sensitivity and reliable quantification and resolves multiple simultaneous signals. MSFI flow cytometry can quantify multiple fluorescent parameters with morphologic or subcellular spatial details on millions of cells. MSFI has the potential to improve the accuracy of disease detection or differentiation and intrasurgical metastatic diagnosis, guide neurosurgeries, and monitor treatment response.
Collapse
Affiliation(s)
- Lanlan Zhou
- Department of Bioengineering, University of Pennsylvania School of Engineering and Applied Science, Philadelphia, Pennsylvania, USA
| | | |
Collapse
|
19
|
Peterson TE, Manning HC. Molecular imaging: 18F-FDG PET and a whole lot more. J Nucl Med Technol 2009; 37:151-61. [PMID: 19692452 DOI: 10.2967/jnmt.109.062729] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
The intention of this review is to provide information about the rapidly evolving field of molecular imaging and its potential impact on the clinical practice of nuclear medicine. On completing this article the reader should be able to define molecular imaging, describe the ways in which molecular imaging can be used, identify some of the biologic processes that can be targeted with molecular imaging agents, and list the modalities that can be used for molecular imaging, along with the strengths and weaknesses of each.
Collapse
Affiliation(s)
- Todd E Peterson
- Institute of Imaging Science, Departments of Radiology and Radiological Sciences, Vanderbilt University, Nashville, Tennessee, USA.
| | | |
Collapse
|