title: Frequent mutations of the Trp53, Hras1 and beta-catenin (Catnb) genes in 1,3-butadiene-induced mammary adenocarcinomas in B6C3F1 mice.
abstract: DNAs from 1,3-butadiene-induced mammary adenocarcinomas of B6C3F1 mice were examined for mutations in the Trp53 gene, the ras gene family and several components of the Wnt signaling pathway, including beta-catenin (Catnb), Apc and Axin. Trp53 mutations were detected in 41% (7 out of 17) of tumors. Each tumor with a Trp53 mutation also exhibited loss of the wild-type Trp53 allele, supporting the importance of Trp53 inactivation during development of these tumors. Analyses of the Hras1, Kras2 and Nras proto-oncogenes revealed Hras1 mutations in 53% (9 out of 17) of tumors. Seven of these mutations were a G-->C transversion in Hras1 codon 13, consistent with a 1,3-butadiene-specific Kras2 mutation previously reported in several other tumor types. Mutation screens in Catnb exon 2, the Apc mutation cluster region and the Catnb-binding domain of the Axin gene identified Catnb missense mutations in 3 out of 17 (18%) tumors. In total, mutations of the Trp53, Hras1 and/or Catnb genes were identified in 15 out of 17 1,3-butadiene-induced mammary adenocarcinomas. These results indicate that multiple genetic pathways are disrupted in chemically induced mammary tumors, and that studies in mouse models may help to understand the etiology of human breast cancers.
authors.affiliation: Division of Cell Biology, Department of Biomedicine and Surgery, Faculty of Health Sciences, Linköping University, SE 581 85 Linköping, Sweden. shizh@mcb.liu.se
authors.forename: Shi-Mei
authors.initials: SM
authors.lastname: Zhuang
authors.forename: Roger W
authors.initials: RW
authors.lastname: Wiseman
authors.forename: Peter
authors.initials: P
authors.lastname: Söderkvist
mesh_terms: D000230:Adenocarcinoma / Q000139:chemically induced / Q000235:genetics*; D000818:Animals; D060466:Axin Protein; D002070:Butadienes; D003062:Codon; D003598:Cytoskeletal Proteins / Q000235:genetics*; D017931:DNA Primers / Q000737:chemistry; D004273:DNA, Neoplasm / Q000378:metabolism; D005260:Female; D017491:Genes, APC / Q000502:physiology; D016158:Genes, p53 / Q000235:genetics*; D011905:Genes, ras / Q000235:genetics*; D019656:Loss of Heterozygosity; D008325:Mammary Neoplasms, Experimental / Q000139:chemically induced / Q000235:genetics*; D051379:Mice; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D017354:Point Mutation / Q000235:genetics*; D016133:Polymerase Chain Reaction; D011506:Proteins / Q000235:genetics; D012097:Repressor Proteins; D015398:Signal Transduction; D015534:Trans-Activators / Q000235:genetics*; D051176:beta Catenin
chemical_list: D060466:Axin Protein; D002070:Butadienes; C495267:CTNNB1 protein, mouse; D003062:Codon; D003598:Cytoskeletal Proteins; D017931:DNA Primers; D004273:DNA, Neoplasm; D011506:Proteins; D012097:Repressor Proteins; D015534:Trans-Activators; D051176:beta Catenin; C031763:1,3-butadiene