DNA cross-link (specifically, phosphoramide mustard-induced DNA cross-link)

DNA cross-linking via alkylation by cyclophosphamide refers to the formation of covalent bonds between two strands of DNA, predominantly at guanine N-7 positions, caused by the active cyclophosphamide metabolite phosphoramide mustard. This leads to inter- and intrastrand cross-links, blocking DNA replication and transcription, and ultimately resulting in cell cycle arrest and apoptosis. This molecular lesion is the primary mediator of cyclophosphamide's cytotoxic effects against cancer and certain immune cells. DNA cross-linking is not a protein or receptor, but a chemical modification of DNA, and represents a cytotoxic damage mechanism rather than a discrete druggable "target"[1][2][3][4][5][6][7][8].

Other names

DNA–DNA cross-linkinterstrand DNA cross-linkDNA alkylation by cyclophosphamideguanine N-7 cross-link

Formation of covalent bonds (alkylation) with DNA at the N-7 position of guanine, leading to DNA cross-links that block replication and transcription, resulting in apoptosis[1][2][3][4][5][6].