Radiochemical investigations of 177Lu-DOTA-8-Aoc-BBN[7-14]NH2: an in vitro/in vivo assessment of the targeting ability of this new radiopharmaceutical for PC-3 human prostate cancer cells

[ 64 Cu-NOTA-8-Aoc-BBN(7-14)NH 2 ] targeting vector for positron-emission tomography imaging of gastrin-releasing peptide receptor-expressing tissues

“…Each of the five chromatograms show a single species with retention times of 8.3, 9.0, 9.2, 8.2, and 7.6 min for pharmacokinetic modifiers X ϭ ␤-Ala (␤-alanine), 5-Ava (5-aminovaleric acid), 8-Aoc (8-aminooctanoic acid), GGG (glycylglycylglycine), and SSS (serylserylserine), respectively. Retention times for the native unlabeled peptides are 9.1, 9.3, 9.9, 8.7, and 8.1 min for X ϭ ␤-Ala, 5-Ava, 8-Aoc, GGG, and SSS, respectively, demonstrating the effectiveness of the HPLC separation procedure to produce high specific activity products ( (34)(35)(36). In human pancreatic tissue, however, the GRPr is expressed only minimally (12), and therefore limits the likelihood of radiotoxicity to normal pancreas of human patients using conjugates of this general type.…”

Bombesin functionalized gold nanoparticles show in vitro and in vivo cancer receptor specificity

“…For example, 99m Tc (H 2 O)(CO) 3 -Dpr-(SSS)-BBN [7][8][9][10][11][12][13][14]NH 2 showed an uptake of 23.3% ID/g and 10.2% ID/g in pancreas and intestines, respectively, 1 h post injection (31), whereas 99m Tc(litorin) showed 23.56% ID/g in pancreas 30 min post injection (32). 177 Lu-DOTA-8-Aoc-BBN [7][8][9][10][11][12][13][14]NH 2 has shown 38.5% ID/g in pancreas and 5.60% ID/g in intestines (33). The slower uptake of 198 AuNP-BBN-3 nanoparticles in kidney (2.46% ID/g after 4 h and 1.58% ID/g after 24 h) suggests that smaller nanoconjugates ( 198 AuNP-BBN-3 <5 nm) are excreted through either the urinary or the hepatobiliary pathway.…”

Novel 111In-labelled bombesin analogues for molecular imaging of prostate tumours

“…Breeman et al reported an increased GRP receptor affinity and tumour uptake when replacing the DTPA chelator with the DOTA chelator coupled to the [Pro 1 ,Tyr 4 ]BN analogue (Cmp 1) [38]. Besides radiolabelling with 111 In, this DOTA chelator enables radiolabelling with positron emitters like 68 Ga and 64 Cu for diagnostic PET imaging and also with β-emitters like 177 Lu and 90 Y; this may permit their use for radiotherapy to treat GRP receptor-positive tumours [26,27,33,34,36,40], comparable to the use of 90 Y-labelled octreotide and 177 Lu-labelled octreotate to treat somatostatin receptor-expressing tumours [48][49][50][51][52][53][54][55]. Also increasing the receptor density on the tumours using gene therapy and, even more interestingly, delivering the radiolabelled analogue directly to the tumour using intratumoral injections to improve tumour uptake are to be studied.…”

“…For example, 99m Tcand 111 In-coupled BN analogues have been developed for diagnostic SPECT imaging and 64 Cu-and 68 Ga-labelled analogues for PET imaging of GRP receptor-expressing tumours [26][27][28][29][30][31][32][33][34][35][36][37][38][39]. In addition, 90 Y-and 177 Lu-labelled analogues have been described as promising tools for targeted radiotherapy of these tumours [26,40].…”