Abstract

Over 3 billion kg/yr of vinyl chloride (VC) are produced in the U.S. VC has been amply documented as a human carcinogen associated with lever haemoangiosarcoma and tumors of the brain and lungs. Although tumors are easily induced in rodents, and VC and its mutagenic metabolites, chloroethylene oxice (CEO) and chlorocetaldehyde (CAA) have been intensively studied, no mechanism for it tumorigenicity has emerged. Among the known products are four cyclic etheno bases. Our long-term objective is to understand the molecular mechanism of initiation by VC, related carcinogens and their common metabolites.
The specific aims are directed towards studying the mispairing potential and repair mechanisms of the four cyclic adducts formed in DNA by vinyl chloride metabolites. The four etheno adducts are N2,3-ethenoG and its isomer 1,N3-ethenoG, as well as 1,N6-ethenoG and 3,N4-ethenoC. Study of repair of these adducts has become important with the recent finding by this laboratory of a human binding protein and a DNA glycosylate that excises ethenoA and ethenoC.
One aim i s to elucidate the mechanisms involved in this binding and removal. An additional aim is to determine whether the other etheno adducts, or those from related cyclic adducts, are also excised by this or other human repair enzymes. Concurrently, incorporated etheno adducts in different neighbor sequences in order to assess their mutagenic potential in vitro. The methods and approaches will involve chemical synthesis of precursor and preparation of oligonucleotides containing a single adduct. Use of such 32p-labeled probes will allow fidelity studies and detection of specific binding proteins using gel assay. Glycosylate action will be determined by HPLC using fluorescence or 3H labeled DNA. Proteins obtained by conventional purification and cloning will be used for obtaining repair enzymes for mechanistic studies. Formation and removal of the four etheno adducts will also be studied in cultured hepatocyte cells, by use of specific antibodies, 32P-postlabeling and HPLC analysis.

  Funding Agency

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Research Project (R01)
Project #
5R01CA047723-07
Application #
2092696
Study Section
Metabolic Pathology Study Section (MEP)
Project Start
1988-02-15
Project End
1996-11-30
Budget Start
1994-12-01
Budget End
1995-11-30
Support Year
7
Fiscal Year
1995
Total Cost
Indirect Cost

  Institution

Name
Lawrence Berkeley National Laboratory
Department
Biology
Type
Organized Research Units
DUNS #
078576738
City
Berkeley
State
CA
Country
United States
Zip Code
94720

  Publications

Xie, Zhongwen; Zhang, Yangbin; Guliaev, Anton B et al. (2005) The p-benzoquinone DNA adducts derived from benzene are highly mutagenic. DNA Repair (Amst) 4:1399-409
Guliaev, Anton B; Singer, B; Hang, Bo (2004) Chloroethylnitrosourea-derived ethano cytosine and adenine adducts are substrates for Escherichia coli glycosylases excising analogous etheno adducts. DNA Repair (Amst) 3:1311-21
Guliaev, Anton B; Hang, Bo; Singer, B (2004) Structural insights by molecular dynamics simulations into specificity of the major human AP endonuclease toward the benzene-derived DNA adduct, pBQ-C. Nucleic Acids Res 32:2844-52
Hang, Bo; Singer, B (2003) Protein-protein interactions involving DNA glycosylases. Chem Res Toxicol 16:1181-95
Hang, Bo; Chenna, Ahmed; Guliaev, Anton B et al. (2003) Miscoding properties of 1,N6-ethanoadenine, a DNA adduct derived from reaction with the antitumor agent 1,3-bis(2-chloroethyl)-1-nitrosourea. Mutat Res 531:191-203
Singer, B; Medina, Michael; Zhang, Yanbin et al. (2002) 8-(Hydroxymethyl)-3,N(4)-etheno-C, a potential carcinogenic glycidaldehyde product, miscodes in vitro using mammalian DNA polymerases. Biochemistry 41:1778-85
Hang, Bo; Downing, Gary; Guliaev, Anton B et al. (2002) Novel activity of Escherichia coli mismatch uracil-DNA glycosylase (Mug) excising 8-(hydroxymethyl)-3,N4-ethenocytosine, a potential product resulting from glycidaldehyde reaction. Biochemistry 41:2158-65
Guliaev, Anton B; Hang, Bo; Singer, B (2002) Structural insights by molecular dynamics simulations into differential repair efficiency for ethano-A versus etheno-A adducts by the human alkylpurine-DNA N-glycosylase. Nucleic Acids Res 30:3778-87
Sagi, J; Guliaev, A B; Singer, B (2001) 15-mer DNA duplexes containing an abasic site are thermodynamically more stable with adjacent purines than with pyrimidines. Biochemistry 40:3859-68
Sagi, J; Perry, A; Hang, B et al. (2000) Differential destabilization of the DNA oligonucleotide double helix by a T.G mismatch, 3,N(4)-ethenocytosine, 3,N(4)-ethanocytosine, or an 8-(hydroxymethyl)-3,N(4)-ethenocytosine adduct incorporated into the same sequence contexts. Chem Res Toxicol 13:839-45

Showing the most recent 10 out of 44 publications