(S)-10-hydroxy-Camptothecin

DNA topoisomerases relax supercoiled DNA during replication, transcription, recombination, repair, and chromosome condensation. The relaxation of DNA supercoiling by topoisomerase I at single-strand breaks represents a target for anticancer agents to intercalate between DNA base pairs, leading to the activation of apoptotic and cell cycle arrest pathways.{21116} (S)-10-hydroxy-Camptothecin is an inhibitor of topoisomerase I originally isolated from the Chinese tree C. acuminata. It is a member of the camptothecin family that demonstrates less toxicity than its parent compound.{23556} (S)-10-hydroxy-Camptothecin has strong anti-tumor activity against a wide range of experimental tumors including L1210 leukemia cells (IC50 = 1.15 ?M).{23556} In vitro treatment of human HepG2 cells with 5-20 ?M (S)-10-hydroxy-camptothecin results in cell cycle arrest at the G2/M phase.{23557}