Bacterial cytidine deaminases as versatile activators of fluoropyrimidine nucleoside prodrugs.

A platform for modification of 5-fluoropyrimidine nucleosides as potential prodrugs has been developed utilizing bacterial-derived cytidine deaminases (CDAs) for activation. It has been demonstrated that CDA_EH, CDA_F14, and CDA_Lsp effectively convert 5-fluoropyrimidine analogs into 5-fluoro-(2'-deoxy)uridine exhibiting cytotoxic effects. Prodrug activation, leading to reduced viability in CDA-expressing cells, has been observed in HCT116, MCF7, and U87MG cancer cell lines. This framework allows the evaluation of various N-acyl/alkyl-5-fluorocytidines, 4-alkylthio-5-fluorouridines, 4-alkoxy-5-fluoro- and 4-alkoxy-5-fluoro-2'-deoxyuridines for their potential use in enzyme-prodrug therapy. Overall, the developed platform provides valuable guidance on selecting both enzyme and prodrug components for the development of effective enzyme-prodrug strategies.