title: Suberoylanilide hydroxamic acid-induced HeLa cell death is closely correlated with oxidative stress and thioredoxin 1 levels.
abstract: Suberoylanilide hydroxamic acid (SAHA) is a histone deacetylase (HDAC) inhibitor which has anticancer effects. We evaluated the growth inhibitory effects of SAHA on HeLa cervical cancer cells in relation to reactive oxygen species (ROS) levels. SAHA inhibited the growth of HeLa cells with an IC(50) of approximately 10 µM at 24 h, and induced apoptosis which was accompanied by the cleavage of PARP, caspase-3 activation and loss of mitochondrial membrane potential (MMP; ∆ψ(m)). All the tested caspase inhibitors prevented HeLa cell death induced by SAHA whereas TNF-α intensified apoptotic cell death in SAHA-treated HeLa cells. With respect to ROS and glutathione (GSH) levels, SAHA increased ROS levels, especially mitochondrial O(2)•- in HeLa cells and also induced GSH depletion. Caspase inhibitors reduced the levels of ROS and GSH depletion in SAHA-treated HeLa cells whereas TNF-α enhanced the levels in these cells. The well-known antioxidant N-acetyl cysteine (NAC) attenuated cell death and an increase in ROS levels was caused by SAHA. Moreover, SAHA decreased the levels of thioredoxin 1 (Trx1) in HeLa cells. While the downregulation of Trx1 enhanced cell death and ROS levels in SAHA-treated HeLa cells, the overexpression of Trx1 attenuated the levels in these cells. In conclusion, SAHA inhibited the growth of HeLa cell via caspase-dependent apoptosis, which was influenced by the mitochondrial O(2)•- and Trx1 levels.
authors.affiliation: Department of Physiology, Medical School, Research Institute for Endocrine Sciences, Chonbuk National University, Jeonju 561-180, Republic of Korea.
authors.forename: Bo Ra
authors.initials: BR
authors.lastname: You
authors.affiliation: Department of Physiology, Medical School, Research Institute for Endocrine Sciences, Chonbuk National University, Jeonju 561-180, Republic of Korea.
authors.forename: Woo Hyun
authors.initials: WH
authors.lastname: Park
mesh_terms: D000230:Adenocarcinoma / Q000378:metabolism / Q000473:pathology*; D000970:Antineoplastic Agents / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects*; D061945:Caspase Inhibitors / Q000494:pharmacology; D020169:Caspases / Q000378:metabolism; D002453:Cell Cycle / Q000187:drug effects; D005260:Female; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D006367:HeLa Cells; D006801:Humans; D006877:Hydroxamic Acids / Q000494:pharmacology*; D066298:In Vitro Techniques; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D017382:Reactive Oxygen Species / Q000378:metabolism*; D013879:Thioredoxins / Q000378:metabolism*; D002583:Uterine Cervical Neoplasms / Q000378:metabolism / Q000473:pathology*; D000077337:Vorinostat
chemical_list: D000970:Antineoplastic Agents; D061945:Caspase Inhibitors; D006877:Hydroxamic Acids; D017382:Reactive Oxygen Species; D013879:Thioredoxins; D000077337:Vorinostat; D020169:Caspases