title: eIF2 kinases mediate β-lapachone toxicity in yeast and human cancer cells.
abstract: β-Lapachone (β-lap) is a novel anticancer agent that selectively induces cell death in human cancer cells, by activation of the NQO1 NAD(P)H dehydrogenase and radical oxygen species (ROS) generation. We characterized the gene expression profile of budding yeast cells treated with β-lap using cDNA microarrays. Genes involved in tolerance to oxidative stress were differentially expressed in β-lap treated cells. β-lap treatment generated reactive oxygen species (ROS), which were efficiently blocked by dicoumarol, an inhibitor of NADH dehydrogenases. A yeast mutant in the mitochondrial NADH dehydrogenase Nde2p was found to be resistant to β-lap treatment, despite inducing ROS production in a WT manner. Most interestingly, DNA damage responses triggered by β-lap were abolished in the nde2Δ mutant. Amino acid biosynthesis genes were also induced in β-lap treated cells, suggesting that β-lap exposure somehow triggered the General Control of Nutrients (GCN) pathway. Accordingly, β-lap treatment increased phosphorylation of eIF2α subunit in a manner dependent on the Gcn2p kinase. eIF2α phosphorylation required Gcn1p, Gcn20p and Nde2p. Gcn2p was also required for cell survival upon exposure to β-lap and to elicit checkpoint responses. Remarkably, β-lap treatment increased phosphorylation of eIF2α in breast tumor cells, in a manner dependent on the Nde2p ortholog AIF, and the eIF2 kinase PERK. These findings uncover a new target pathway of β-lap in yeast and human cells and highlight a previously unknown functional connection between Nde2p, Gcn2p and DNA damage responses.
authors.affiliation: a Instituto de Genética Experimental ; Facultad de Ciencias Médicas ; Universidad Nacional de Rosario ; Rosario , Argentina.
authors.forename: Mauricio
authors.initials: M
authors.lastname: Menacho-Márquez
authors.forename: Carlos J
authors.initials: CJ
authors.lastname: Rodríguez-Hernández
authors.forename: M Ángeles
authors.initials: MÁ
authors.lastname: Villaronga
authors.forename: Jorge
authors.initials: J
authors.lastname: Pérez-Valle
authors.forename: José
authors.initials: J
authors.lastname: Gadea
authors.forename: Borja
authors.initials: B
authors.lastname: Belandia
authors.forename: José R
authors.initials: JR
authors.lastname: Murguía
mesh_terms: D000970:Antineoplastic Agents / Q000378:metabolism / Q000494:pharmacology*; D001728:Dicumarol / Q000494:pharmacology; D004789:Enzyme Activation / Q000187:drug effects*; D006801:Humans; D015151:Immunoblotting; D016660:NAD(P)H Dehydrogenase (Quinone) / Q000037:antagonists & inhibitors / Q000378:metabolism; D009285:Naphthoquinones / Q000378:metabolism / Q000494:pharmacology*; D020411:Oligonucleotide Array Sequence Analysis; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D034741:RNA, Small Interfering / Q000235:genetics; D017382:Reactive Oxygen Species / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism; D004718:Saccharomycetales; D013778:Tetrazolium Salts; D013844:Thiazoles; D059467:Transcriptome; D019892:eIF-2 Kinase / Q000378:metabolism*
chemical_list: D000970:Antineoplastic Agents; D009285:Naphthoquinones; D034741:RNA, Small Interfering; D017382:Reactive Oxygen Species; D029701:Saccharomyces cerevisiae Proteins; D013778:Tetrazolium Salts; D013844:Thiazoles; C014638:beta-lapachone; D001728:Dicumarol; D016660:NAD(P)H Dehydrogenase (Quinone); C447479:NQO1 protein, human; C512912:GCN2 protein, S cerevisiae; D017346:Protein Serine-Threonine Kinases; D019892:eIF-2 Kinase; C022616:thiazolyl blue
keywords: DNA damage; GCN, General Control of Nutrients; GO, Gene Ontology; ISR, Integrated Stress Response; ROS, Reactive Oxygen Species; antitumoral drug; integrated stress response; reactive oxygen species; β-lap, β-lapachone