Molecular imaging, pharmacokinetics, and dosimetry of [sup.111]In-AMBA in human prostate tumor-bearing mice

Molecular imaging with promise of personalized medicine can provide patient-specific information noninvasively, thus enabling treatment to be tailored to the specific biological attributes of both the disease and the patient. This study was to investigate the characterization of DO3A-C[H.sub.2]CO-G-4-aminobenzoyl-Q-W-A-V-G-H-L-M-N[H.sub.2] (AMBA) in vitro, MicroSPECT/CT imaging, and biological activities of [sup.111]In-AMBA in PC-3 prostate tumor-bearing SCID mice. The uptake of [sup.111]In-AMBA reached highest with 3.87 ± 0.65% ID/g at 8h. MicroSPECT/CT imaging studies suggested that the uptake of [sup.111]In-AMBA was clearly visualized between 8 and 48 h postinjection. The distribution half-life ([t.sub.1/2a]) and the elimination half-life ([t.sub.1/2])of [sup.111]In-AMBA in mice were 1.53 h and 30.7 h, respectively. The [C.sub.m]ax and AUC of [sup.111]In-AMBA were 7.57% ID/g and 66.39 h* % ID/g, respectively. The effective dose appeared to be 0.11 mSv/[MBq.sup.-1]. We demonstrated a good uptake of [sup.111]In-AMBA in the GRPR-overexpressed PC-3 tumor-bearing SCID mice. [sup.111]In-AMBA is a safe, potential molecular image-guided diagnostic agent for human GRPR-positive tumors, ranging from simple and straightforward biodistribution studies to improve the efficacy of combined modality anti- cancer therapy.
1. Introduction Prostate cancer is estimated to rank first in number of cancer cases and second in number of deaths due to cancer among men in the Western world [1]. [...]