Referenced in: none

Automatically associated channels: Slo1

Title: Preclinical imaging evaluation of novel TSPO-PET ligand 2-(5,7-Diethyl-2-(4-(2-[(18)F]fluoroethoxy)phenyl)pyrazolo[1,5-a]pyrimidin-3-yl)-N,N-diethylacetamide ([ (18)F]VUIIS1008) in glioma.

Authors: Dewei Tang, Michael L Nickels, M Noor Tantawy, Jason R Buck, H Charles Manning

Journal, date & volume: Mol Imaging Biol, 2014 Dec , 16, 813-20

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/24845529

Abstract
Translocator protein (TSPO) concentrations are elevated in glioma, suggesting a role for TSPO positron emission tomography (PET) imaging in this setting. In preclinical PET studies, we evaluated a novel, high-affinity TSPO PET ligand, [(18)F]VUIIS1008, in healthy mice and glioma-bearing rats.Dynamic PET data were acquired simultaneously with [(18)F]VUIIS1008 injection, with binding reversibility and specificity evaluated in vivo by non-radioactive ligand displacement or blocking. Compartmental analysis of PET data was performed using metabolite-corrected arterial input functions. Imaging was validated with histology and immunohistochemistry.[(18)F]VUIIS1008 exhibited rapid uptake in TSPO-rich organs. PET ligand uptake was displaceable with non-radioactive VUIIS1008 or PBR06 in mice. Tumor accumulation of [(18)F]VUIIS1008 was blocked by pretreatment with VUIIS1008 in rats. [(18)F]VUIIS1008 exhibited improved tumor-to-background ratio and higher binding potential in tumors compared to a structurally similar pyrazolopyrimidine TSPO ligand, [(18)F]DPA-714.The PET ligand [(18)F]VUIIS1008 exhibits promising characteristics as a tracer for imaging glioma. Further translational studies appear warranted.