Campathecin 是有效的 DNA拓扑异构酶 I 抑制剂，IC50 值为 679 nM。
CAS：7689-03-4
分子式：C20H16N2O4
分子量：348.35
纯度：98%
存储：Store at -20°C

Background:

Campathecin is a potent DNA enzyme topoisomerase I inhibitor, with an IC50 of 679 nM. Topoisomerase I|679 nM (IC50)

[3H]BrCPT labeling of topoisomerase I is enhanced greatly by the presence of DNA; very little labeling of isolated topoisomerase I or isolated DNA occurrs. Even in the presence of DNA, [3H]BrCPT labeling of topoisomerase I is inhibited by camptothecin, suggesting that both CPT and BrCPT bind to the same site on the DNA-topoisomerase I binary complex[1]. With increasing concentrations of camptothecin, closed circular pRR322 DNA (form I) is converted to nicked circular DNA (form 11). This apparent nicking activitv of camptothecin required DNA topoisomerase I[2].

[1]. Hertzberg RP, et al. Irreversible trapping of the DNA-topoisomerase I covalent complex. Affinity labeling of the camptothecin binding site. J Biol Chem. 1990 Nov 5;265(31):19287-95. [2]. Hsiang YH, et al. Camptothecin induces protein-linked DNA breaks via mammalian DNA topoisomerase I. J Biol Chem. 1985 Nov 25;260(27):14873-8. [3]. Luzzio MJ, et al. Synthesis and antitumor activity of novel water soluble derivatives of camptothecin as specific inhibitors of topoisomerase I. Synthesis and antitumor activity of novel water soluble derivatives of camptothecin as specific inhibitors of topoisomerase I.