Genomic DNA and DNA replication machinery

Genomic DNA and the DNA replication machinery represent the collective biological targets for several purine analog antimetabolites, most notably fludarabine. This target complex includes the physical DNA template and essential enzymes such as DNA polymerase alpha, delta, and epsilon, as well as ribonucleotide reductase and DNA primase (Gandhi & Plunkett, 2002, https://pubmed.ncbi.nlm.nih.gov/11830467/). Fludarabine triphosphate, the active metabolite, competes with deoxyadenosine triphosphate for incorporation into the DNA strand, which subsequently inhibits further chain elongation and DNA repair processes (StatPearls, 2023, https://www.ncbi.nlm.nih.gov/books/NBK557443/). This interference with the replication machinery leads to the accumulation of DNA strand breaks and the induction of apoptosis, particularly in lymphoid cells. The target is central to the treatment of chronic lymphocytic leukemia (CLL) and other indolent B-cell malignancies (NCI, https://www.cancer.gov/publications/dictionaries/cancer-drug/def/fludarabine-phosphate). Because this machinery is also active in healthy hematopoietic cells, its inhibition leads to significant side effects such as prolonged lymphopenia and myelosuppression. Understanding the interaction between fludarabine triphosphate and these molecular components is crucial for optimizing dosing and managing treatment-related toxicities.

Other names

DNA synthesis machineryDNA replication complexNuclear DNA

Fludarabine triphosphate acts as a competitive inhibitor of DNA polymerases (alpha, delta, and epsilon) and ribonucleotide reductase, while also being incorporated into the genomic DNA strand to cause premature chain termination (Gandhi & Plunkett, 2002, https://pubmed.ncbi.nlm.nih.gov/11830467/).