Ultrasound Molecular Imaging of VEGFR2 in a Rat Prostate Tumor Model Using BR55.
Summary of "Ultrasound Molecular Imaging of VEGFR2 in a Rat Prostate Tumor Model Using BR55."
: To evaluate BR55, a new VEGFR2-specific ultrasound contrast agent, for imaging prostate tumors in an orthotopic model in the rat. MATERIALS AND
: Rat prostate adenocarcinoma were established by injection of G Dunning R-3327 tumor cells in one lobe of the prostate of Copenhagen rats. Imaging experiments were performed with BR55, SonoVue, and streptavidin-functionalized microbubbles coupled with an anti-vascular endothelial growth factor receptor 2 (VEGFR2) antibody using a clinical ultrasound scanner. Contrast enhancement in the tumor and healthy prostate was followed over time by intermittent imaging at low acoustic power. Signal quantification and statistical analysis were performed in the tumor and healthy tissue to compare the behavior of the 3 contrast agents. Immunohistochemistry was performed on the prostate and tumor specimen to determine the expression of VEGFR2.
: Comparable contrast enhancement was observed in tumors at peak intensity for BR55 and SonoVue. Then, once unbound microbubbles had cleared from the circulation, a strong enhancement of the tumor was obtained with BR55, whereas no significant microbubble accumulation was detected in the healthy prostate tissue. SonoVue microbubbles were rapidly eliminated, and no significant binding was observed in the tumor. The tumor to prostate ratio calculated after signal quantification was about 20 for the 3 doses of BR55 tested. The enhancement obtained with BR55 in the tumor was not significantly different from the one observed with antibody-coupled streptavidin microbubbles. Intense staining for VEGFR2 was detected in the tumor vessels by immunohistochemistry.
: This study showed that BR55 binding to prostate tumors resulted in a strong enhancement of the lesions as early as a few minutes after contrast injection, whereas minimal nonspecific accumulation occurred in the healthy part of the gland. BR55, like Sonovue, provide information on tissue perfusion during the early vascular phase, but BR55 binding to the tumoral endothelium allows to gain additional information by highlighting the sites of active angiogenesis. The late phase enhancement of the tumor should be particularly valuable for prostate cancer detection and for biopsy guidance.
From the *Preclinical Ultrasound Department, Bracco Research SA, Geneva, Switzerland; and daggerThe Ernst Felder Laboratories, Bracco Research USA, Princeton, NJ.
This article was published in the following journal.
Name: Investigative radiology
- PubMed Source: http://www.ncbi.nlm.nih.gov/pubmed/20808233
- DOI: http://dx.doi.org/10.1097/RLI.0b013e3181ee8b83
Catching bubbles: Tetrazine-functionalized microbubbles were prepared for use as ultrasound contrast agents, and shown to selectively localize on cells labeled with a TCO-derivatized antibody against ...
Prostate cancer is one of the most common neoplasms in men. Transrectal ultrasound (TRUS)-guided systematic biopsy has a crucial role in the diagnosis of prostate cancer. However, it shows limited val...
Ultrasound (US) molecular imaging by examining the expression of vascular endothelial growth factor receptor 2 (VEGFR2) on uterus vascular endothelium was applied to evaluate the endometrial receptivi...
Biomechanical model based deformable image registration has been widely used to account for prostate deformation in various medical imaging procedures. Biomechanical material properties are important ...
Increasing appreciation of tumor heterogeneity and the tumor-host interaction has stimulated interest in developing novel therapies that target both tumor cells and tumor microenvironment. Bone marrow...
The primary objective is to perform a pilot trial evaluation of a novel prostate ultrasound imaging software utilizing tissue elasticity measurements to identify tumor foci among men who w...
RATIONALE: Highly focused ultrasound energy may be able to kill tumor cells by heating the tumor without affecting the surrounding tissue. PURPOSE: This phase II trial is studying the sid...
The purpose of this study is to determine the sensitivity of Molecular Breast Imaging (MBI) relative to MRI of the breast in patients undergoing MRI for a clinical concern, or abnormal dia...
RATIONALE: New imaging procedures such as CT-on-rails™ may improve the ability to pinpoint the location of the tumor and decrease radiation therapy damage to healthy tissue. PURPOSE: Th...
The purpose of this study is to determine the substantial equivalence of the Ablatherm high intensity focused ultrasound (HIFU) as compared to cryotherapy for the treatment of low risk, lo...
Medical and Biotech [MESH] Definitions
Tissue ablation of the PROSTATE performed by ultrasound from a transducer placed in the RECTUM. The procedure is used to treat prostate cancer (PROSTATIC NEOPLASMS) and benign prostatic hypertrophy (PROSTATIC HYPERPLASIA).
The use of molecularly targeted imaging probes to localize and/or monitor biochemical and cellular processes via various imaging modalities that include RADIONUCLIDE IMAGING; ULTRASONOGRAPHY; MAGNETIC RESONANCE IMAGING; fluorescence imaging; and MICROSCOPY.
The use of ultrasound to guide minimally invasive surgical procedures such as needle ASPIRATION BIOPSY; DRAINAGE; etc. Its widest application is intravascular ultrasound imaging but it is useful also in urology and intra-abdominal conditions.
A diagnostic technique that incorporates the measurement of molecular diffusion (such as water or metabolites) for tissue assessment by MRI. The degree of molecular movement can be measured by changes of apparent diffusion coefficient (ADC) with time, as reflected by tissue microstructure. Diffusion MRI has been used to study BRAIN ISCHEMIA and tumor response to treatment.
Proteins secreted by the prostate gland. The major secretory proteins from the human prostate gland include PROSTATE-SPECIFIC ANTIGEN, prostate-specific acid phosphatase, prostate-specific membrane antigen, and prostate-specific protein-94.