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A Novel 99mTc-Labeled Molecular Probe for Tumor Angiogenesis Imaging in Hepatoma Xenografts Model: A Pilot Study.
- Source :
- PLoS ONE; Apr2013, Vol. 8 Issue 4, p1-11, 11p
- Publication Year :
- 2013
-
Abstract
- Introduction: Visualization of tumor angiogenesis using radionuclide targeting provides important diagnostic information. In previous study, we proved that an arginine-arginine-leucine (RRL) peptide should be a tumor endothelial cell specific binding sequence. The overall aim of this study was to evaluate whether <superscript>99m</superscript>Tc-radiolabeled RRL could be noninvasively used for imaging of malignant tumors in vivo, and act as a new molecular probe targeting tumor angiogenesis. Methods: The RRL peptide was designed and radiosynthesized with <superscript>99m</superscript>Tc by a one-step method. The radiolabeling efficiency and radiochemical purity were then characterized in vitro. <superscript>99m</superscript>Tc-RRL was injected intravenously in HepG2 xenograft-bearing BALB/c nude mice. Biodistribution and in vivo imaging were performed periodically. The relationship between tumor size and %ID uptake of <superscript>99m</superscript>Tc-RRL was also explored. Results: The labeling efficiencies of <superscript>99m</superscript>Tc-RRL reached 76.9%±4.5% (n = 6) within 30–60 min at room temperature, and the radiochemical purity exceeded 96% after purification. In vitro stability experiment revealed the radiolabeled peptide was stable. Biodistribution data showed that <superscript>99m</superscript>Tc-RRL rapidly cleared from the blood and predominantly accumulated in the kidneys and tumor. The specific uptake of <superscript>99m</superscript>Tc-RRL in tumor was significantly higher than that of unlabeled RRL blocking and free pertechnetate control test after injection (p<0.05). The ratio of the tumor-to-muscle exceeded 6.5, tumor-to-liver reached 1.98 and tumor-to-blood reached 1.95. In planar gamma imaging study, the tumors were imaged clearly at 2–6 h after injection of <superscript>99m</superscript>Tc-RRL, whereas the tumor was not imaged clearly in blocking group. The tumor-to-muscle ratio of images with <superscript>99m</superscript>Tc-RRL was comparable with that of <superscript>18</superscript>F-FDG PET images. Immunohistochemical analysis verified the excessive vasculature of tumor. There was a linear relationship between the tumor size and uptake of <superscript>99m</superscript>Tc-RRL with R<superscript>2</superscript> = 0.821. Conclusion: <superscript>99m</superscript>Tc-RRL can be used as a potential candidate for visualization of tumor angiogenesis in malignant carcinomas. [ABSTRACT FROM AUTHOR]
Details
- Language :
- English
- ISSN :
- 19326203
- Volume :
- 8
- Issue :
- 4
- Database :
- Complementary Index
- Journal :
- PLoS ONE
- Publication Type :
- Academic Journal
- Accession number :
- 87677969
- Full Text :
- https://doi.org/10.1371/journal.pone.0061043