SN-38

Description

*-Ethyl***-hydroxycamptothecin (also known as SN*8) is a metabolite of irinotecan hydrochloride (CPT**1). SN*8 is a topoisomerase I inhibitor and has potential applications as an anti-tumour agent however its water insolubility presents challenges in terms of bioavailability. Topoisomerase I relaxes the tightly bound DNA double helix and breaks one DNA strand to allow for DNA replication, the topoisomerase-DNA complex is short-lived and once DNA replication is complete topoisomerase reforms the DNA strand. SN*8 prolongs the lifetime of the topoisomerase I-DNA complex and inhibits the DNA reforming step, as a result cleavage of the second DNA strand can occur leading to cell death.