RT Journal Article
SR Electronic
T1 Evaluation of tumor targeting efficacy of 67Ga-labeled bombesin peptide functionalized gold nanoparticle in mice model
JF Journal of Nuclear Medicine
JO J Nucl Med
FD Society of Nuclear Medicine
SP 1386
OP 1386
VO 55
IS supplement 1
A1 Zambre, Ajit
A1 Silva, Francisco
A1 Upendran, Anandhi
A1 Gano, Lurdes
A1 Paulo, Antonio
A1 Kannan, Raghuraman
YR 2014
UL http://jnm.snmjournals.org/content/55/supplement_1/1386.abstract
AB 1386 Objectives Prostate cancer is the second most leading cause of cancer death in men. Gastrin releasing peptide (GRP) receptors are over-expressed in prostate cancer. Bombesin (BBN) is a peptide with 14-aminoacids that has high affinity toward GRP receptors. In this study, we synthesized 67Ga labeled bombesin functionalized gold nanoparticles [BBN-AuNP(DTDTPA)(67Ga)] and evaluated the GRP receptor targeting efficacy in prostate tumor mice model. Methods [BBN-AuNP(DTDTPA)] has been successfully synthesized and radiolabelled with 67Ga. Radio-TLC was performed to identify the purity of [BBN-AuNP(DTDTPA)(67Ga)]. The non-radioactive surrogate was characterized by conventional analytical techniques including UV-Vis, High Resolution Transmission Electron Microscopy (HRTEM), Dynamic Light Scattering method (DLS), and X-ray photoelectron spectroscopy (XPS). Biodistribution study was performed in PC-3 tumor bearing nude-mice xenografts in groups of 3, by intravenous tail vein administration of [BBN-AuNP(DTDTPA)(67Ga)] (1.5-6.0 MBq). Mice were sacrificed at 15 min, 30min, 4 h, and 24 h post injection and the uptake tumor was monitored. Results DLS measurements show the hydrodynamic diameter of [BBN-AuNP(DTDTPA)(Ga)] is 113±5nm. HRTEM confirmed a metallic core size is 3-5nm. XPS study indicated the covalent bonding of “thiol ligand” present in BBN ligand to gold. Biodistribution study revealed a ~6 fold higher uptake in tumor after 24 hours post injection time point when compared to that of non-targeted AuNP-DTDTPA-67Ga. Conclusions We have synthesized and characterized [BBN-AuNP(DTDTPA)(67Ga)] for GRP receptor targeting. The nanoconjugate can be used for imaging both primary and metastatic prostate tumor in humans. Research Support Fundação para a Ciência e Tecnologia (FCT) is acknowledged for financial support (EXCL/QEQ-MED/0233/2012). F. Silva thanks the FCT for a Doctoral research grant (SFRH/BD/47308/2008)).”