posted on 2021-12-22, 19:06authored byTao Zhang, Jinghua Cai, Muyun Xu, Xinrui Ma, Hui Wang, Mengzhe Wang, Zhaoguo Han, Jason Wang, Eric Smith, Zibo Li, Zhanhong Wu
Radiolabeled prostate-specific membrane
antigen (PSMA) ligands
have been rapidly adopted as part of patient care for prostate cancer.
In this study, a new series of 18F-labeled PSMA-targeting
agents was developed based on the high-affinity Glu-ureido-Lys scaffold
and 18F-vinyl sulfones (VSs), the tumor uptake and tumor/major
organ contrast of which could be tuned by pharmacokinetic linkers
within the molecules. In particular, 18F-PEG3-VS-PSMAi showed the highest tumor uptake (12.1 ± 2.2%ID/g at
0.5 h p.i.) and 18F-PEG2-VS-PSMAi showed the
highest tumor-to-liver ratio (T/L = 3.7 ± 1.0, 4.8 ± 1.2,
and 6.3 ± 1.1 at 0.5, 1.5, and 3 h p.i. respectively). Significantly,
compared with the FDA-approved 68Ga-PSMA-11, the newly
developed 18F-PEG3-VS-PSMAi has an almost double
tumor uptake (P < 0.0001) when tested in the same
animal model. In conclusion, 18F-VS-labeled PSMA ligands
are promising PET agents with prominent tumor uptake and high contrast.
The lead agents 18F-PEG2-VS-PSMAi and 18F-PEG3-VS-PSMAi warrant further evaluation in prostate
cancer patients.