title: DDTD, an isoflavone derivative, induces cell apoptosis through the reactive oxygen species/apoptosis signal-regulating kinase 1 pathway in human osteosarcoma cells.
abstract: Osteosarcoma is the most common primary bone tumor associated with childhood and adolescence. In the present study, we investigated the anticancer effect of a new isoflavone derivative, 3',4'-dichloro-3-(3,4-dichlorophenylacetyl)-2,4,6-trihydroxydeoxybenzoin (DDTD) in human osteosarcoma cells. DDTD induced cell apoptosis in human osteosarcoma cell lines (including: U2OS, MG-63, Saos2 and ROS 17/2.8). We found that the accumulation of reactive oxygen species is a critical mediator in DDTD-induced cell death. DDTD induced apoptosis signal-regulating kinase 1 (ASK1) dephosphorylation and its dissociation from 14-3-3. Treatment of osteosarcoma cells with DDTD induced p38 and p53 phosphorylation. Transfection with ASK1, mitogen activated protein kinase (MAPK) kinase (MKK)3/6, and p38 small interfering RNA (siRNA) antagonized the DDTD-induced cell apoptosis. DDTD also triggered the mitochondrial apoptotic pathway, as indicated by a change in Bax/Bcl2 ratio and Caspase-9 activation. Bax knockdown using a Bax siRNA strategy reduced Bax expression and subsequent cell death. In addition, transfection of cells with ASK1, MKK3/6, and p38 siRNA reduced DDTD-induced p38 activation, p53 phosphorylation and Bax expression. These results suggest that DDTD generates reactive oxygen species and activates the ASK1-MKK3/6-p38-p53-Bax pathway to cause osteosarcoma cell death.
authors.affiliation: School of Pharmacy, China Medical University, Taichung, Taiwan.
authors.forename: Jung-Tsan
authors.initials: JT
authors.lastname: Chen
authors.forename: Yi-Chin
authors.initials: YC
authors.lastname: Fong
authors.forename: Te-Mao
authors.initials: TM
authors.lastname: Li
authors.forename: Ju-Fang
authors.initials: JF
authors.lastname: Liu
authors.forename: Che-Wei
authors.initials: CW
authors.lastname: Hsu
authors.forename: Chih-Shiang
authors.initials: CS
authors.lastname: Chang
authors.forename: Chih-Hsin
authors.initials: CH
authors.lastname: Tang
mesh_terms: D048948:14-3-3 Proteins / Q000378:metabolism; D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects*; D053453:Caspase 9 / Q000378:metabolism; D045744:Cell Line, Tumor; D004305:Dose-Response Relationship, Drug; D006801:Humans; D007529:Isoflavones / Q000494:pharmacology*; D048371:MAP Kinase Kinase 3 / Q000378:metabolism; D048669:MAP Kinase Kinase 6 / Q000378:metabolism; D048848:MAP Kinase Kinase Kinase 5 / Q000235:genetics / Q000378:metabolism*; D008928:Mitochondria / Q000201:enzymology / Q000473:pathology; D012516:Osteosarcoma / Q000201:enzymology / Q000235:genetics / Q000473:pathology*; D010766:Phosphorylation; D048789:Phytoestrogens / Q000494:pharmacology*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism*; D015398:Signal Transduction / Q000187:drug effects*; D013997:Time Factors; D014162:Transfection; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism; D051028:bcl-2-Associated X Protein / Q000378:metabolism; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism
chemical_list: D048948:14-3-3 Proteins; C533502:3',4'-dichloro-3-(3,4-dichlorophenylacetyl)-2,4,6-trihydroxydeoxybenzoin; D000972:Antineoplastic Agents, Phytogenic; C494826:BAX protein, human; D007529:Isoflavones; D048789:Phytoestrogens; D019253:Proto-Oncogene Proteins c-bcl-2; D034741:RNA, Small Interfering; D017382:Reactive Oxygen Species; C495901:TP53 protein, human; D016159:Tumor Suppressor Protein p53; D051028:bcl-2-Associated X Protein; D048051:p38 Mitogen-Activated Protein Kinases; D048848:MAP Kinase Kinase Kinase 5; C482858:MAP3K5 protein, human; D048371:MAP Kinase Kinase 3; D048669:MAP Kinase Kinase 6; C482530:MAP2K3 protein, human; C482566:MAP2K6 protein, human; C506433:CASP9 protein, human; D053453:Caspase 9