Nitric oxide inhibits topoisomerase II activity and induces resistance to topoisomerase II-poisons in human tumor cells

摘要

Background: Etoposide and doxorubicin, topoisomerase II poisons, are important drugs for the treatment of tumors in the clinic. Topoisomerases contain several free sulfhydryl groups which are important for their activity and are also potential targets for nitric oxide ((NO)-N-center dot)-induced nitrosation. (NO)-N-center dot, a physiological signaling molecule nitrosates many cellular proteins, causing altered protein and cellular functions.