Effects and the mechanism of manumycin on KAT-18 anaplastic thyroid cancer cells / 实用医学杂志

ABSTRACT

Objective To explore the effects and the mechanism of manumycin on KAT-18 cells Methods Human ATC (anaplastic thyroid cancer) KAT-18 cells were used. The cytotoxicity was analyzed by SRB assay. Apoptosis and cellular nitric oxide were detected by flow cytometry using annexin v and NO sensor dye. Superoxide anion was measured with a fluorescent plate reader by DHE.GSH was assayed by fluorescent Monochlorobimane. The SOD activities were assayed by colorimetric methods. The protein expression of Mn-SOD was determined by western blot. Results Manumycin decreased the viability of KAT-18 cells in a dose-dependent manner. Manumycin induced apoptosis significantly and NO generation simultaneously. Manumycin also induced superoxide anions generation. Manumycin reduced intracellular GSH in a time-course manner. However , manumycin did not decrease the SOD activity after 6 h treatment and Mn-SOD expression. A delayed induction of SOD activity was observed after 24 h manumycin treatment. N-acetyl-L-cysteine blocked NO and superoxide anions generation and apoptosis induction by Manumycin. Furthermore , NAC protected KAT-18 cells from the cytotoxicity of manumycin. Conclusion Manumycin induces apoptosis and has cytotoxic effects on KAT-18 cells. Cellular NO and superoxide anions generation are required for Manumycin-induced apoptosis in KAT-18 cells.