Imaging Therapeutic PARP Inhibition In Vivo through Bioorthogonally Developed Companion Imaging Agents

Autor: Thomas Reiner, Jessica Lacy, Edmund J. Keliher, Katherine S. Yang, Adeeti Ullal, Rainer H. Kohler, Claudio Vinegoni, Ralph Weissleder
Jazyk: angličtina
Rok vydání: 2012
Předmět:
Zdroj: Neoplasia: An International Journal for Oncology Research, Vol 14, Iss 3, Pp 169-177 (2012)
Druh dokumentu: article
ISSN: 1476-5586
1522-8002
DOI: 10.1593/neo.12414
Popis: A number of small-molecule poly (ADP-ribose) polymerase (PARP) inhibitors are currently undergoing advanced clinical trials. Determining the distribution and target inhibitory activity of these drugs in individual subjects, however, has proven problematic. Here, we used a PARP agent for positron emission tomography-computed tomography (PET-CT) imaging (18F-BO), which we developed based on the Olaparib scaffold using rapid bioorthogonal conjugation chemistries. We show that the bioorthogonal 18F modification of the parent molecule is simple, highly efficient, and well tolerated, resulting in a half maximal inhibitory concentration (IC50) of 17.9 ± 1.1 nM. Intravital imaging showed ubiquitous distribution of the drug and uptake into cancer cells, with ultimate localization within the nucleus, all of which were inhibitable. Whole-body PET-CT imaging showed tumoral uptake of the drug, which decreased significantly, after a daily dose of Olaparib. Standard 18F-fludeoxyglucose imaging, however, failed to detect such therapy-induced changes. This research represents a step toward developing a more generic approach for the rapid codevelopment of companion imaging agents based on small-molecule therapeutic inhibitors.
Databáze: Directory of Open Access Journals