title: Analysis of cell death inducing compounds.
abstract: Biomarkers for early detection of toxicity hold the promise of improving the failure rates in drug development. In the present study, gene expression levels were measured using full-genome RAE230 version 2 Affymetrix GeneChips on rat liver tissue 48 h after administration of six different compounds, three toxins (ANIT, DMN and NMF) and three non-toxins (Caeruelein, Dinitrophenol and Rosiglitazone). We identified three gene transcripts with exceptional predictive performance towards liver toxicity and/or changes in histopathology. The three genes were: glucokinase regulatory protein (GCKR), ornithine aminotransferase (OAT) and Cytochrome P450, subfamily IIC (mephenytoin 4-hydroxylase) (Cyp2C29). RT-PCR for these three genes was performed and four additional compounds were included for validation. The quantitative RT-PCR analysis confirmed the findings based on the microarray data and using the three genes a classification rate of 55 of 57 samples was achieved for the classification of not toxic versus toxic. The single most promising biomarker (OAT) alone resulted in a surprisingly 100% correctly classified samples. OAT has not previously been linked to toxicity and cell death in the literature and the novel finding represents a putative hepatotoxicity biomarker.
authors.affiliation: Center for Biological Sequence Analysis, BioCentrum-DTU, Technical University of Denmark, Kemitorvet, Building 208, 2800, Lyngby, Denmark. hbjorn@cbs.dtu.dk
authors.forename: Jeppe S
authors.initials: JS
authors.lastname: Spicker
authors.forename: Henrik Toft
authors.initials: HT
authors.lastname: Pedersen
authors.forename: Henrik Bjørn
authors.initials: HB
authors.lastname: Nielsen
authors.forename: Søren
authors.initials: S
authors.lastname: Brunak
mesh_terms: D000410:Alanine Transaminase / Q000378:metabolism; D000818:Animals; D001219:Aspartate Aminotransferases / Q000378:metabolism; D018554:Avena / Q000235:genetics*; D002352:Carrier Proteins / Q000235:genetics*; D016923:Cell Death / Q000235:genetics*; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics*; D000072467:Cytochrome P450 Family 2; D020869:Gene Expression Profiling; D008099:Liver / Q000378:metabolism* / Q000473:pathology; D008297:Male; D020411:Oligonucleotide Array Sequence Analysis; D010105:Oxygenases / Q000235:genetics*; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D002352:Carrier Proteins; C080906:glucokinase regulatory protein; D003577:Cytochrome P-450 Enzyme System; D010105:Oxygenases; C086292:Cyp2c29 protein, mouse; D000072467:Cytochrome P450 Family 2; D001219:Aspartate Aminotransferases; D000410:Alanine Transaminase