Patricia M.R. Pereira#, Sheryl Roberts#, Flavio Figueira, Joao P. C. Tome, Thomas Reiner and Jason S. Lewis*
# Equally contributed
Galectins are carbohydrate-binding proteins overexpressed in bladder cancer (BCa) cells. Dendritic galactose moieties have a high affinity for galectin-expressing tumor cells. We radiolabeled a dendritic galactose carbohydrate with fluorine-18 – 18F-labeled galactodendritic unit 4 – and examined its potential in imaging urothelial malignancies. Methods: The 18F-labeled 1st generation galactodendritic unit 4 was obtained from its tosylate precursor. We conducted in vivo studies in galectin-expressing UMUC3 orthotopic BCa model to determine the ability of 18F-labeled galactodendritic unit 4 to image BCa. Results: Intravesical administration of 18F-labeled galactodendritic unit 4 allowed specific accumulation of the carbohydrate radiotracer in galectin-1 overexpressing UMUC3 orthotopic tumors when imaged with PET. The 18F-labeled galactodendritic unit 4 was not found to accumulate in non-tumor murine bladders. Conclusion: The 18F-labeled galactodendritic unit 4 and similar analogs may be clinically relevant and exploitable for PET imaging of galectin-1 overexpressing bladder tumors.