PPAT and hepatocellular carcinoma: In research on nucleotide anabolism in hepatocellular carcinoma, dual-specificity tyrosine phosphorylation-regulated kinase 3 (Dyrk3) was found to limit de novo purine anabolism by regulating the transcriptional activity of ATF4 and inhibiting the rate-limiting de novo purine anabolism-related enzyme 5′-phosphoribosyl pyrophosphate amidotransferase (PPAT), thereby inhibiting the growth and metastasis of hepatocellular carcinoma [64].