ImmunoPET Imaging of Trop2 Expression in Bladder Cancer Using [<sup>64</sup>Cu]Cu-NOTA-Trodelvy
Wenpeng Huang, Tianyao Wang, Fangfang Chao, Qi Yang, Jason C. Mixdorf, Liming Li, Jonathan W. Engle, Fan Yu, Lei Kang, Weibo Cai
Abstract
Trop2 exhibits significantly elevated expression in numerous solid malignancies, playing a crucial role in tumor advancement, whereas its presence in healthy tissues is minimal. In this study, we investigated Trop2 expression in bladder cancer models using [ 64 Cu]Cu-NOTA-Trodelvy for immunoPET imaging. In HT-1376 models, [ 64 Cu]Cu-NOTA-Trodelvy effectively visualized tumor as early as 12 h p.i. (10.30 ± 1.45% ID/g), with tumor uptake increasing and peaking at 48 h p.i. (13.73 ± 1.16% ID/g), highlighting its potential for tumor imaging. Control groups also demonstrated low tumor uptake (5.27 ± 1.14% ID/g at 48 h in the blocking group; 6.33 ± 0.74% ID/g at 48 h in UM-UC-3; 4.50 ± 0.30% ID/g at 48 h in the [ 64 Cu]Cu-NOTA-IgG group). Long-term fluorescence imaging further confirmed the tumor uptake rate in the IRDye 800CW-Trodelvy group was significantly higher than in the IRDye 800CW-Trodelvy blockade group ( P < 0.001). Our findings demonstrated that [ 64 Cu]Cu-NOTA-Trodelvy enables specific and prolonged tumor accumulation in bladder cancer models, providing precise and noninvasive monitoring of Trop2 expression.