Synthesis, Radiolabelling and In Vitro Characterization of the Gallium-68-, Yttrium-90- and Lutetium-177-Labelled PSMA Ligand, CHX-A''-DTPA-DUPA-Pep.
Since prostate-specific membrane antigen (PSMA) has been identified as a diagnostic target for prostate cancer, many urea-based small PSMA-targeting molecules were developed. First, the clinical application of these Ga-68 labelled compounds in positron emission tomography (PET) showed their diagnostic potential. Besides, the therapy of prostate cancer is a demanding field, and the use of radiometals with PSMA bearing ligands is a valid approach. In this work, we describe the synthesis of a new PSMA ligand, CHX-A''-DTPA-DUPA-Pep, the subsequent labelling with Ga-68, Lu-177 and Y-90 and the first in vitro characterization. In cell investigations with PSMA-positive LNCaP C4-2 cells, KD values of ≤14.67 ± 1.95 nM were determined, indicating high biological activities towards PSMA. Radiosyntheses with Ga-68, Lu-177 and Y-90 were developed under mild reaction conditions (room temperature, moderate pH of 5.5 and 7.4, respectively) and resulted in nearly quantitative radiochemical yields within 5 min.
Clinic for Nuclear Medicine, University of Ulm, Albert-Einstein-Allee, 89081 Ulm, Germany. benjamin.baur@uniklinik-ulm.de.
Benjamin
B
Baur
Clinic for Nuclear Medicine, University of Ulm, Albert-Einstein-Allee, 89081 Ulm, Germany. christoph.solbach@uniklinik-ulm.de.
Christoph
C
Solbach
Clinic for Nuclear Medicine, University of Ulm, Albert-Einstein-Allee, 89081 Ulm, Germany. elena.andreolli@gmail.com.
Elena
E
Andreolli
Clinic for Nuclear Medicine, University of Ulm, Albert-Einstein-Allee, 89081 Ulm, Germany. gordon.winter@uniklinik-ulm.de.
Gordon
G
Winter
Clinic for Nuclear Medicine, University of Ulm, Albert-Einstein-Allee, 89081 Ulm, Germany. hans.machulla@uniklinik-ulm.de.
Hans-Jürgen
HJ
Machulla
Clinic for Nuclear Medicine, University of Ulm, Albert-Einstein-Allee, 89081 Ulm, Germany. sven.reske@uniklinik-ulm.de.
Sven N
SN
Reske