title: DJ-1 mediates the resistance of cancer cells to dihydroartemisinin through reactive oxygen species removal.
abstract: Dihydroartemisinin (DHA), one of the main metabolites of artemisinin and its derivatives, presents anti-cancer potential in vitro and in vivo. To explore the mechanisms of resistance toward DHA, a DHA-resistant cell line, HeLa/DHA, was established with a resistance factor of 7.26 in vitro. Upon DHA treatment, apoptotic cells were significantly elicited in parental HeLa cells but minimally induced in HeLa/DHA cells. HeLa/DHA cells also displayed much less sensitivity to DHA-induced tumor suppression in cancer xenograft models than HeLa cells. Intriguingly, DHA-resistant cells did not display a multidrug-resistant phenotype. Based on a proteomic study employing LC-ESI-MS/MS together with pathway analysis, DJ-1 (PARK7) was found to be highly expressed in HeLa/DHA cells. Western blot and immunofluorescence assays confirmed the higher expression of DJ-1 in HeLa/DHA cells than in parental cells in both cell line and xenograft models. DJ-1 is translocated to the mitochondria of HeLa/DHA cells and oxidized, providing DJ-1 with stronger cytoprotection activity. Further study revealed that DJ-1 knockdown in HeLa/DHA cells abolished the observed resistance, whereas overexpression of DJ-1 endowed the parental HeLa cells with resistance toward DHA. Reactive oxygen species (ROS) were also significantly induced by either DHA or hydrogen peroxide in HeLa cells but not in resistant HeLa/DHA cells. When the cells were pretreated with N-acetyl-l-cysteine, the effect of DJ-1 knockdown on sensitizing HeLa/DHA cells to DHA was significantly attenuated. In summary, our study suggests that overexpression and mitochondrial translocation of DJ-1 provides HeLa/DHA cells with resistance to DHA-induced ROS and apoptosis.
authors.affiliation: Zhejiang Province Key Laboratory of Anti-cancer Drug Research, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China. Electronic address: hongzhu@zju.edu.cn.
authors.forename: Hong
authors.initials: H
authors.lastname: Zhu
authors.affiliation: Zhejiang Province Key Laboratory of Anti-cancer Drug Research, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China.
authors.forename: Si-Da
authors.initials: SD
authors.lastname: Liao
authors.affiliation: College of Life Sciences, Zhejiang Chinese Medical University, Hangzhou, Zhejiang 310053, China.
authors.forename: Jia-Jie
authors.initials: JJ
authors.lastname: Shi
authors.affiliation: Zhejiang Province Key Laboratory of Anti-cancer Drug Research, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China.
authors.forename: Lin-Lin
authors.initials: LL
authors.lastname: Chang
authors.affiliation: Department of Medicine, Cedars-Sinai Medical Center, University of California at Los Angeles School of Medicine, Los Angeles, CA 90095, USA.
authors.forename: Yun-Guang
authors.initials: YG
authors.lastname: Tong
authors.affiliation: Zhejiang Province Key Laboratory of Anti-cancer Drug Research, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China.
authors.forename: Ji
authors.initials: J
authors.lastname: Cao
authors.affiliation: Zhejiang Province Key Laboratory of Anti-cancer Drug Research, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China.
authors.forename: Ying-Ying
authors.initials: YY
authors.lastname: Fu
authors.affiliation: State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macao, China.
authors.forename: Xiu-Ping
authors.initials: XP
authors.lastname: Chen
authors.affiliation: Zhejiang Province Key Laboratory of Anti-cancer Drug Research, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China.
authors.forename: Mei-Dan
authors.initials: MD
authors.lastname: Ying
authors.affiliation: Zhejiang Province Key Laboratory of Anti-cancer Drug Research, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China.
authors.forename: Bo
authors.initials: B
authors.lastname: Yang
authors.affiliation: Zhejiang Province Key Laboratory of Anti-cancer Drug Research, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China.
authors.forename: Qiao-Jun
authors.initials: QJ
authors.lastname: He
authors.affiliation: State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macao, China. Electronic address: jinjian.lu@163.com.
authors.forename: Jin-Jian
authors.initials: JJ
authors.lastname: Lu
mesh_terms: D000111:Acetylcysteine / Q000494:pharmacology; D000818:Animals; D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology*; D017209:Apoptosis; D037621:Artemisinins / Q000494:pharmacology*; D019008:Drug Resistance, Neoplasm; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006367:HeLa Cells; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology; D051379:Mice; D008819:Mice, Nude; D008928:Mitochondria / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D015513:Oncogene Proteins / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D054464:Peroxiredoxins; D000071617:Protein Deglycase DJ-1; D021381:Protein Transport; D040901:Proteomics; D034741:RNA, Small Interfering / Q000235:genetics / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism*; D015398:Signal Transduction; D023041:Xenograft Model Antitumor Assays
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D037621:Artemisinins; D015513:Oncogene Proteins; D034741:RNA, Small Interfering; D017382:Reactive Oxygen Species; C039060:artenimol; D006861:Hydrogen Peroxide; D054464:Peroxiredoxins; C503466:PARK7 protein, mouse; D000071617:Protein Deglycase DJ-1; D000111:Acetylcysteine
keywords: DJ-1; Dihydroartemisinin; Free radicals; Mitochondria; Proteomic; Resistant