Record Display for the EPA National Library Catalog


Main Title Consistent Oncogene Methylation Changes in Epithelial Cells Chemically Transformed In vitro.
Author Mass, M. J. ; Schorschinsky, N. S. ; Lasley, J. A. ; Beeman, D. K. ; Austin, S. J. ;
CORP Author Environmental Health Research and Testing, Inc., Research Triangle Park, NC.;Health Effects Research Lab., Research Triangle Park, NC. Genetic Toxicology Div.
Publisher c31 Oct 89
Year Published 1989
Report Number EPA-68-02-4456; EPA/600/J-89/383;
Stock Number PB90-216169
Additional Subjects Epithelium ; Lung neoplasms ; Deoxyribonucleic acids ; Methylation ; In vitro analysis ; Rats ; Mutation ; Reprints ; Oncogenes ; Southern immunoblotting ; Transformed cell line ; Base sequence ; Nucleic acid hybridization ; Ras genes
Library Call Number Additional Info Location Last
NTIS  PB90-216169 Some EPA libraries have a fiche copy filed under the call number shown. 07/26/2022
Collation 9p
Many cancers occurring in humans and in animals are accompanied by alterations in oncogene DNA sequences, amplification, or changes in expression. In some cases the changes are quite specific and prevalent such as in Burkitt's lymphoma, pancreatic, and thyroid carcinoma. Studies of human lung cancers have revealed heterogeneous activated oncogenes in varied proportions of tumors and prompted researchers to consider that genetic events present in established tumors may not be reflective of those occurring early in precursor initiated cells. The rat tracheal epithelial (RTE) cell transformation system has been utilized as a surrogate to study early molecular events in respiratory carcinogenesis. RTE cells transformed by chemical carcinogens in vitro and early preneoplastic lesions in vivo have been examined. However, RTE cells transformed by polycyclic hydrocarbons appear to sustain no consistent changes in Ha-ras, c-myc, and Ki-ras oncogenes by restriction fragment length polymorphism analysis, and DNA isolated from these cells is devoid of transfectable transforming genes in NIH3T3 cells. In the present study it has been determined that rat tracheal epithelial cells transformed by diverse carcinogens share common changes in DNA methylation patterns in Ha-ras and c-myc oncogenes as determined by Hpa II digestion. This is the first report of a common molecular alteration for these cells.