DNA guanine (G)

DNA guanine bases are critical components of the genetic code, serving as one of the four primary nucleobases in deoxyribonucleic acid (PubChem CID 135398). In oncology, guanine is a major therapeutic target due to the high nucleophilicity of its N7 and O6 positions, which makes it susceptible to attack by electrophilic cytotoxic agents (Nature Reviews Cancer, 2005, 5, 253-265). Drugs such as platinum complexes and alkylating agents form stable covalent bonds with guanine, resulting in DNA adducts and cross-links (Journal of Biological Chemistry, 2004, 279, 12786-12791). These structural modifications distort the DNA double helix, blocking the progression of DNA polymerase and RNA polymerase. Additionally, guanine-rich sequences can form G-quadruplexes, which are targets for novel stabilizing ligands aimed at inhibiting telomerase and oncogene expression (Nucleic Acids Research, 2017, 45, 23-32). Consequently, the cell's inability to repair or bypass these lesions leads to cell cycle arrest and the activation of apoptotic pathways, particularly in rapidly proliferating malignant cells.

Other names

Guanine2-amino-1,9-dihydro-6H-purin-6-oneG-residuesDeoxyguanosineDNA guanine bases in oligodeoxynucleotides

Formation of covalent DNA adducts and cross-links at the N7 or O6 positions of guanine, leading to the inhibition of DNA synthesis and the induction of apoptosis.