|An alkaloid isolated from the stem wood of the Chinese tree, Camptotheca acuminata. This compound selectively inhibits the nuclear enzyme DNA topoisomerase, type I. Several semisynthetic analogs of camptothecin have demonstrated antitumor activity. [PubChem]
Antineoplastic Agents, Phytogenic
21,22-Secocamptothecin-21-oic acid lactone
Investigated for the treatment of cancer.
Camptothecin demonstrated strong anticancer activity in preliminary clinical trials but also low solubility and adverse drug reaction. Camptothecin is believed to be a potent topoisomerase inhibitor that interferes with the essential function of topoisomerase in DNA replication.
mechanism of action
Camptothecin binds to the topoisomerase I and DNA complex (the covalent complex) resulting in a ternary complex, and thereby stabilizing it. This prevents DNA relegation and therefore causes DNA damage which results in apoptosis.
Acute oral toxicity (LD50
) in mouse: 50.1 mg/kg