title: Induction of apoptosis in human ovarian cancer cells by new anticancer compounds, epothilone A and B.
abstract: Epothilones are a new group of compounds with action mechanisms similar to taxanes. The aim of this study was to compare the effects of epothilone A (Epo A) and epothilone B (Epo B) on ovarian cancer cell line SKOV-3 with those of paclitaxel (PTX), a classic taxane. We evaluate glycoprotein P (P-gp) activity in the ovarian cancer cell line. Apoptotic and necrotic cell levels were measured by double staining with Hoechst 33258 and propidium iodide (PI) as well as Annexin V staining. The production of reactive oxygen species (ROS) and changes in mitochondrial membrane potential (ΔΨm) in cells exposed to Epo A, Epo B and PTX were studied using specific fluorescence probes, DCFH(2)-DA (2',7'-dichlorodihydrofluorescein diacetate) and JC-1 (5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolcarbocyanine). The cytotoxic activity of the drugs was determined by the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide) test. All probes were analyzed in both the presence and absence of the antioxidant N-acetylcysteine (NAC). The results obtained demonstrated that the antiproliferative capacity of Epo A and Epo B in SKOV-3 cell line (measured as IC(50) after 72 h continuous treatment) was six and five times greater than that of PTX's respectively. Epothilones induced timecourse-dependent apoptosis and necrosis. Apoptotic and necrotic events were partially blocked by NAC, indicating ROS played a substantial role in epothilone-induced apoptosis. Cell death was also associated with a decrease in mitochondrial membrane potential, which was more pronounced after treatment with epothilones as compared to paclitaxel.
authors.affiliation: Department of Thermobiology, Institute of Biophysics, Faculty of Biology and Environmental Protection, University of Lodz, Pomorska 141/143, 90-236 Lodz, Poland. zychan@biol.uni.lodz.pl
authors.forename: Aneta
authors.initials: A
authors.lastname: Rogalska
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Marczak
authors.forename: Arkadiusz
authors.initials: A
authors.lastname: Gajek
authors.forename: Marzena
authors.initials: M
authors.lastname: Szwed
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Śliwińska
authors.forename: Józef
authors.initials: J
authors.lastname: Drzewoski
authors.forename: Zofia
authors.initials: Z
authors.lastname: Jóźwiak
mesh_terms: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000378:metabolism; D000970:Antineoplastic Agents / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D034261:Epothilones / Q000494:pharmacology*; D005260:Female; D006801:Humans; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D010051:Ovarian Neoplasms; D017239:Paclitaxel / Q000494:pharmacology; D017382:Reactive Oxygen Species / Q000378:metabolism
chemical_list: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D000970:Antineoplastic Agents; D034261:Epothilones; D017382:Reactive Oxygen Species; C093787:epothilone A; D017239:Paclitaxel; C093788:epothilone B