A Preclinical Study on GRPR-Targeted 68Ga-Probes for PET Imaging of Prostate Cancer.

Gastrin-releasing peptide receptors (GRPR) targeted positron emission tomography (PET) is a highly promising approach for imaging of prostate cancer (PCa) in small animal models and patients. Developing a GRPR-targeted PET probe with excellent in vivo performance such as high tumor uptake, high contrast and optimal pharmacokinetics is still very challenging. Herein, a novel bombesin (BBN) analog (named as SCH1) based on JMV594 peptide modified with an 8-amino octanoic acid spacer (AOC) was thus designed and conjugated with the metal chelator 1,4,7-triazacyclononane,1-glutaric acid-4,7-acetic acid (NODAGA). The resulting NODAGA-SCH1 was then radiolabeled with 68Ga and evaluated for PET imaging of PCa. Compared with 68Ga-NODAGA-JMV594 probe, 68Ga-NODAGA-SCH1 exhibited excellent PET/CT imaging properties on PC-3 tumor-bearing nude mice, such as high tumor uptake (5.80 ± 0.42 vs 3.78 ± 0.28 %ID/g, 2h) and high tumor/muscle contrast (16.6 ± 1.50 vs 8.42 ± 0.61 %ID/g, 2h). Importantly, biodistribution data indicated a relatively similar accumulation of 68Ga-NODAGA-SCH1 was observed in the liver (4.21 ± 0.42 %ID/g) and kidney (3.41 ± 0.46 %ID/g) suggesting that the clearance is both through the kidney and the liver. Overall, 68Ga-NODAGA-SCH1 showed promising in vivo properties and is a promising candidate for translation into clinical PET-imaging of PCa patients.

Bioconjugate chemistry. 2016 Jul 11 [Epub ahead of print]

Yao Sun, Xiaowei Ma, Zhe Zhang, Ziyan Sun, Mathias Loft, Bingbing Ding, Changhao Liu, Liying Xu, Meng Yang, Yuxin Jiang, Jianfeng Liu, Yuling Xiao, Zhen Cheng, Xuechuan Hong

E-Newsletters

Newsletter subscription

Free Daily and Weekly newsletters offered by content of interest

The fields of GU Oncology and Urology are rapidly advancing. Sign up today for articles, videos, conference highlights and abstracts from peer-review publications by disease and condition delivered to your inbox and read on the go.

Subscribe