Description:Topotecan (NSC609699, Nogitecan HCl, SKFS 104864A; trade name: Hycamtin), an FDA approved drug for cancer treatment, is a topoisomerase I inhibitor for MCF-7 Luc cells and DU-145 Luc cells with IC50 of 13 nM and 2 nM in cell-free assays, respectively. It is a semisynthetic derivative of camptothecin with antineoplastic activity. During the S phase of the cell cycle, topotecan selectively stabilizes topoisomerase I-DNA covalent complexes, inhibiting religation of topoisomerase I-mediated single-strand DNA breaks and producing potentially lethal double-strand DNA breaks when complexes are encountered by the DNA replication machinery.

References: Anticancer Drugs. 2003 Aug;14(7):569-74; Blood. 1995 May 15;85(10):2817-28.

Related CAS#: 123948-87-8 (free base) 119413-54-6 (HCl) 123949-08-6 (Carboxylic Acid Sodium)