UCK2 and hepatocellular carcinoma: Uridine‐cytidine kinase 2 (UCK2), which can catalyze the phosphorylation of uridine and cytidine to uridine monophosphate (UMP) and cytidine monophosphate (CMP), is associated with cell proliferation and is a potential unfavorable prognostic predictor for HCC prognosis.43