Use of suppression-PCR subtractive hybridisation to identify genes that demonstrate altered expression in male rat and guinea pig livers following exposure to Wy-14,643, a peroxisome proliferator and non-genotoxic hepatocarcinogen.
Understanding the genetic profile of a cell at all stages of normal and carcinogenic development should provide an essential aid to developing new strategies for the prevention, early detection, diagnosis and treatment of cancers. We have attempted to identify some of the genes that may be involved in peroxisome-proliferator (PP)-induced non-genotoxic hepatocarcinogenesis using suppression PCR subtractive hybridisation (SSH). Wistar rats (male) were chosen as a representative susceptible species and Duncan-Hartley guinea pigs (male) as a resistant species to the hepatocarcinogenic effects of the PP, [4-chloro-6-(2,3-xylidino)-2-pyrimidinylthio] acetic acid (Wy-14,643). In each case, groups of four test animals were administered a single dose of Wy-14,643 (250 mg/kg per day in corn oil) by gastric intubation for 3 consecutive days. The control animals received corn oil only. On the fourth day the animals were killed and liver mRNA extracted. SSH was carried out using mRNA extracted from the rat and guinea pig livers, and used to isolate genes that were up and downregulated following Wy-14,643 treatment. These genes included some predictable (and hence positive control) species such as CYP4A1 and CYP2C11 (upregulated and downregulated in rat liver, respectively). Several genes that may be implicated in hepatocarcinogenesis have also been identified, as have some unidentified species. This work thus provides a starting point for developing a molecular profile of the early effects of a non-genotoxic carcinogen in sensitive and resistant species that could ultimately lead to a short-term assay for this type of toxicity.
Rockett
J C
JC
Molecular Toxicology Group, School of Biological Sciences, University of Surrey, Guildford, UK.
Swales
K E
KE
Esdaile
D J
DJ
Gibson
G G
GG
D000818:Animals; D002273:Carcinogens / Q000633:toxicity*; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics; D017931:DNA Primers; D005786:Gene Expression Regulation / Q000187:drug effects*; D006168:Guinea Pigs; D008099:Liver / Q000187:drug effects / Q000378:metabolism*; D008114:Liver Neoplasms, Experimental / Q000139:chemically induced* / Q000473:pathology; D008297:Male; D020025:Peroxisome Proliferators / Q000494:pharmacology*; D011743:Pyrimidines / Q000494:pharmacology*; D012333:RNA, Messenger / Q000096:biosynthesis; D051381:Rats; D017208:Rats, Wistar; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods*; D014158:Transcription, Genetic / Q000187:drug effects
D002273:Carcinogens; D017931:DNA Primers; D020025:Peroxisome Proliferators; D011743:Pyrimidines; D012333:RNA, Messenger; C006253:pirinixic acid; D004247:DNA