Bioconjug Chem 2018 02 9;29(2):410-419. Epub 2018 Jan 9.
Laboratory of Molecular Imaging and Nanomedicine, National Institute of Biomedical Imaging and Bioengineering (NIBIB), National Institutes of Health (NIH) , Bethesda, Maryland 20892, United States.
Radiolabeled bombesin (BBN) analogs have long been used for developing gastrin-releasing peptide receptor (GRPR) targeted imaging probes, and tracers with excellent in vivo performance including high tumor uptake, high contrast, and favorable pharmacokinetics are highly desired. In this study, we compared the Ga-labeled GRPR agonist (Gln-Trp-Ala-Val-Gly-His-Leu-Met-NH, BBN) and antagonist (d-Phe-Gln-Trp-Ala-Val-Gly-His-Sta-Leu-NH, RM26) for the positron emission tomography (PET) imaging of prostate cancer. The in vitro stabilities, receptor binding, cell uptake, internalization, and efflux properties of the probes Ga-1,4,7-triazacyclononane-1,4,7-triacetic acid (NOTA)-Aca-BBN and Ga-NOTA-poly(ethylene glycol) (PEG)-RM26 were studied in PC-3 cells, and the in vivo GRPR targeting abilities and kinetics were investigated using PC-3 tumor xenografted mice. Read More