Abstract
Proliferating cancer cells reprogramme metabolism to secure nucleotides and other macromolecules required for biomass accumulation and genome duplication. Beyond serving as DNA/RNA precursors, nucleotides act as energy currencies, second messengers, glycosyl donors, and modulators of cytoskeletal dynamics; sustaining adequate pools is therefore indispensable for tumour growth and progression. Oncogenic lesions, such as loss of TP53 or LKB1, hyperactive PI3K-AKT-mTORC1, and MYC or RAS, coordinate transcriptional programmes, substrate transport, and post-translational control of rate-limiting enzymes to elevate de novo purine and pyrimidine synthesis and shape salvage use. These circuits integrate glycolysis, the pentose-phosphate pathway, folate-dependent one-carbon metabolism, and glutamine/aspartate provisioning to channel carbon and nitrogen into ring assembly. In this review, we organize this landscape into an environment-shaped routing model that explains when tumours favour de novo versus salvage and how therapies reroute flux. We synthesise current mechanisms by which oncogenes and tumour suppressors regulate nucleotide synthesis in cancer and outline therapeutic implications, including inhibitors of pathway enzymes (e.g., DHODH, IMPDH), strategies that restrict precursor availability, and rational combinations with targeted agents or DNA-damaging therapies to exploit replication stress and metabolic vulnerabilities. Together, these insights highlight nucleotide metabolism as a central, drug-responsive nexus linking oncogenic signalling to malignant proliferation.