title: [The expression of C-myc, N-ras mRNA and its relations to the differentiation of preneoplastic altered hepatocytes].
abstract: The expression of C-myc and N-ras mRNA was studied in preneoplastic hepatic lesions induced by multiple small doses of diethylnitrosamine (DEN). Dot blot analysis showed that the expression of C-myc and N-ras mRNA was in elevated levels during the early stage of hepatocarcinogenesis. In situ hybridization in tissue sections demonstrated that the over-expression of C-myc and N-ras mRNA was clearly seen in some of the preneoplastic altered liver cell lesions. In comparison of these over-expressed oncogene lesions with the expression of carbamyl phosphate synthetase I (CPS I), known as a differentiation marker of hepatocytes, in serial sections revealed that almost all of the foci with over-expressed C-myc and/or N-ras mRNA also showed low expression of CPS I mRNA, which means a low differentiation nature of the liver cells. These findings suggested that the overexpression of C-myc and N-ras are closely correlated to the differentiation state of altered liver cells.
authors.affiliation: Department of Pathology, Chinese Academy of Medical Sciences, Beijing.
authors.forename: Y Z
authors.initials: YZ
authors.lastname: Lin
mesh_terms: D000818:Animals; D002223:Carbamoyl-Phosphate Synthase (Glutamine-Hydrolyzing) / Q000032:analysis; D002454:Cell Differentiation; D004052:Diethylnitrosamine; D015972:Gene Expression Regulation, Neoplastic; D016259:Genes, myc; D011905:Genes, ras; D017403:In Situ Hybridization; D008099:Liver / Q000473:pathology; D008114:Liver Neoplasms, Experimental / Q000139:chemically induced / Q000201:enzymology / Q000235:genetics*; D008297:Male; D011230:Precancerous Conditions / Q000139:chemically induced / Q000201:enzymology / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics*; D051381:Rats; D017208:Rats, Wistar
chemical_list: D012333:RNA, Messenger; D004052:Diethylnitrosamine; D002223:Carbamoyl-Phosphate Synthase (Glutamine-Hydrolyzing)