Uridine-cytidine kinase (UCK (UCK1, UCK2))

Uridine-cytidine kinase is a key enzyme family in pyrimidine metabolism, phosphorylating uridine and cytidine as the first step of the salvage pathway critical for RNA and DNA synthesis. Two well-characterized human isoforms are UCK1, which is ubiquitously expressed in healthy tissues, and UCK2, which is mainly expressed in placenta and several cancer types, making it a biomarker and therapeutic target in oncology. The enzyme has a well-defined structure with active-site residues conferring specificity for ribonucleosides, and magnesium ions acting as cofactors. UCK2 is frequently overexpressed in tumors and plays a role in the bioactivation of nucleoside analog drugs, with potential implications for cancer treatment. Inhibition or modulation of UCK activity affects cell proliferation, apoptosis, and potentially immune responses

Other names

Uridine-cytidine kinaseUCKUridine-cytidine nucleoside kinaseUCK1UCK2Uridine-cytidine kinase like-1 (UCKL-1)

Prodrug activation: UCK2 phosphorylates nucleoside analog drugs to their cytotoxic monophosphate forms in tumor cells Enzyme inhibition: Drugs inhibiting UCK2 block pyrimidine salvage, impairing nucleotide synthesis and tumor growth