(Adapted for the investigators's abstract) The primary objective of the proposed research is to characterized and understand the molecular, cellular and biochemical events that occur following exposure of human epithelial cells to genotoxic agents. It is thought that the persistence of certain DNA base modifications alter gene expression which may change the stage of cellular differentiation and directly contribute to the transformed state. The hypothesis of the study is that genotoxins cause a change in the differentiated state of the normal cell which may be a precursor to the transformed phenotype. Thus, the role of DNA damage and repair in the modulation of selected genes involved in cellular differentiation will be addressed in human liver epithelial cells. These liver cell cultures are easily subpassed, replicatively active and exhibit many of the in vivo organ """"""""specific biochemical and differentiated functions. These can provide data relevant to the normal human liver and other human epithelial tissues. The present focus of this project will be to characterize the specific carcinogen DNA adducts associated with changes in the genes for alpha-fetoprotein (FP)_, gamma-glutamyl transpeptidase (GFT), glucose-6- phosphatase (G6P) and cytokeratins in these cells that go on to transformation. These genes are associated with live specific cellular function and differentiation, and alternations in these proteins occur during the initial stages of chemically induced hepatocarcinoma. It is hoped that the proposed studies will provide new information and insights into the mechanisms that lead to human cell genotoxicity.

Agency
National Institute of Health (NIH)
Institute
National Institute of Environmental Health Sciences (NIEHS)
Type
Research Project (R01)
Project #
5R01ES005727-03
Application #
3254020
Study Section
Toxicology Subcommittee 2 (TOX)
Project Start
1991-06-01
Project End
1996-05-31
Budget Start
1993-06-01
Budget End
1994-05-31
Support Year
3
Fiscal Year
1993
Total Cost
Indirect Cost
Name
Ohio State University
Department
Type
Schools of Medicine
DUNS #
098987217
City
Columbus
State
OH
Country
United States
Zip Code
43210
D'Ambrosio, S M; Gibson-D'Ambrosio, R E; Brady, T et al. (2001) Mechanisms of nitric oxide-induced cytotoxicity in normal human hepatocytes. Environ Mol Mutagen 37:46-54
D'Ambrosio, S M; Oberyszyn, T M; Brady, T et al. (1997) Sensitivity of human hepatocytes in culture to reactive nitrogen intermediates. Biochem Biophys Res Commun 233:545-9
Wani, G; Wani, A A; D'Ambrosio, S M (1993) Cell type-specific expression of the O6-alkylguanine-DNA alkyltransferase gene in normal human liver tissues as revealed by in situ hybridization. Carcinogenesis 14:737-41
Gibson-D'Ambrosio, R E; Crowe, D L; Shuler, C E et al. (1993) The establishment and continuous subculturing of normal human adult hepatocytes: expression of differentiated liver functions. Cell Biol Toxicol 9:385-403