DNA (epirubicin intercalation)

Epirubicin is an anthracycline antineoplastic agent that exerts its cytotoxic effects primarily through direct interaction with DNA. The principal mechanism involves the intercalation of epirubicin’s planar aromatic rings between adjacent base pairs of double-stranded DNA. This physical insertion distorts the helical structure of DNA, impeding essential cellular processes such as replication and transcription. Epirubicin also inhibits topoisomerase II, leading to DNA strand breaks and cell death. Additionally, it can generate cytotoxic free radicals. Epirubicin's action is not limited to direct genotoxicity; it can also modulate gene expression independently from causing overt strand breaks.

Intercalation of epirubicin between DNA base pairs, inhibition of topoisomerase II, generation of free radicals.