Cellular proteins and other macromolecular nucleophiles

Cellular proteins and other macromolecular nucleophiles encompass a diverse set of biological molecules, including DNA, RNA, and proteins, that possess electron-rich functional groups capable of reacting with electrophilic compounds. These nucleophilic sites, such as the N7 position of guanine in DNA or the sulfhydryl groups in cysteine residues, are the primary reactive targets for cytotoxic alkylating agents and platinum-based chemotherapeutics (NIH, 2023). By forming covalent adducts or cross-links, these drugs disrupt essential cellular processes like DNA replication and transcription, triggering apoptosis in rapidly dividing cancer cells (PubMed, 2022). However, the ubiquitous nature of these nucleophiles across all cell types leads to significant off-target effects, which are a major limiting factor in clinical use. Common toxicities include myelosuppression, neurotoxicity, and the potential for therapy-related secondary malignancies due to DNA damage in healthy tissues (StatPearls, 2024). The interaction with these macromolecules is also a central theme in toxicology, where the formation of protein or DNA adducts serves as a biomarker for exposure to hazardous electrophilic chemicals (PubChem, 2024). Consequently, while these macromolecules are considered targets in the context of traditional chemotherapy, modern drug development often seeks more specific molecular targets to improve the therapeutic index and reduce systemic harm.

Other names

Biological nucleophilesEndogenous nucleophilesCellular macromoleculesNucleophilic targets

Covalent modification of nucleophilic centers (e.g., sulfhydryl, amino, and phosphate groups) through alkylation, arylation, or coordination, resulting in DNA cross-linking, enzyme inhibition, and induction of apoptosis (NIH, 2023; PubMed, 2022).