title: Arsenic trioxide induces apoptosis through a reactive oxygen species-dependent pathway and loss of mitochondrial membrane potential in HeLa cells.
abstract: Arsenic trioxide (As2O3) can induce clinical remission in patients with acute promyelocytic leukemia (APL) through induction of apoptosis. To investigate the potential therapeutic usage of As2O3 in cervical cancer and its possible mechanisms, human cervical cancer cell line HeLa was employed. The cells underwent apoptosis in response to As2O3, accompanied by a decrease of mitochondrial membrane potential and caspase-3 activation. Overexpression of Bcl-2, however, prevented the dissipation of mitochondrial membrane potential, subsequently protecting the cells from As2O3-induced apoptosis. As2O3 increased cellular content of reactive oxygen species (ROS), especially hydrogen peroxide (H2O2), and the antioxidant N-acetyl-L-cysteine completely suppressed As2O3-induced apoptosis. Furthermore, incubation of the cells with catalase resulted in significant suppression of As2O3-induced apoptosis. The above results indicate that the induction of HeLa cell apoptosis by As2O3 involved an early decrease in cellular mitochondrial membrane potential and increase in ROS content, predominantly H2O2, followed by caspase-3 activation and DNA fragmentation.
authors.affiliation: Laboratory of Cell Biology, Korea Cancer Center Hospital, Seoul 139-706, Korea.
authors.forename: Sang Hyeok
authors.initials: SH
authors.lastname: Woo
authors.forename: In-Chul
authors.initials: IC
authors.lastname: Park
authors.forename: Myung-Jin
authors.initials: MJ
authors.lastname: Park
authors.forename: Hyung-Chahn
authors.initials: HC
authors.lastname: Lee
authors.forename: Su-Jae
authors.initials: SJ
authors.lastname: Lee
authors.forename: Yong-Jin
authors.initials: YJ
authors.lastname: Chun
authors.forename: Seung-Hoon
authors.initials: SH
authors.lastname: Lee
authors.forename: Seok-Il
authors.initials: SI
authors.lastname: Hong
authors.forename: Chang Hun
authors.initials: CH
authors.lastname: Rhee
mesh_terms: D000111:Acetylcysteine / Q000494:pharmacology; D000970:Antineoplastic Agents / Q000494:pharmacology*; D000975:Antioxidants / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects*; D000077237:Arsenic Trioxide; D001152:Arsenicals / Q000494:pharmacology*; D020169:Caspases / Q000378:metabolism*; D002374:Catalase / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004789:Enzyme Activation; D006367:HeLa Cells / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D006801:Humans; D006861:Hydrogen Peroxide / Q000378:metabolism; D008564:Membrane Potentials / Q000187:drug effects; D008928:Mitochondria / Q000187:drug effects* / Q000502:physiology; D010087:Oxides / Q000494:pharmacology*; D017382:Reactive Oxygen Species / Q000378:metabolism*; D015398:Signal Transduction / Q000187:drug effects*
chemical_list: D000970:Antineoplastic Agents; D000975:Antioxidants; D001152:Arsenicals; D010087:Oxides; D017382:Reactive Oxygen Species; D006861:Hydrogen Peroxide; D002374:Catalase; D020169:Caspases; D000077237:Arsenic Trioxide; D000111:Acetylcysteine