Targeting PSMA with a Cu-64 Labeled Phosphoramidate Inhibitor for PET/CT Imaging of Variant PSMA-Expressing Xenografts in Mouse Models of Prostate Cancer

摘要

Prostate-specific membrane antigen (PSMA) is highly up-regulated in prostate tumor cells, providing an ideal target for imaging applications of prostate cancer. CTT-1297 (IC50 = 27 nM) is an irreversible phosphoramidate inhibitor of PSMA that has been conjugated to the CB-TE1K1P chelator for incorporation of Cu-64. The resulting positron emission tomography (PET) agent, [Cu-64]ABN-1, was evaluated for selective uptake both in vitro and in vivo in PSMA-positive cells of varying expression levels. The focus of this study was to assess the ability of [Cu-64]ABN-1 to detect and distinguish varying levels of PSMA in a panel of prostate tumor-bearing mouse models.