Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1993-2-23
pubmed:abstractText
Polycyclic aromatic hydrocarbons (PAHs), such as benzo[a]pyrene (BaP), cause vascular lesions of atherosclerotic etiology in avian and rodent species. Because the development of these lesions is associated with aberrant proliferation of vascular smooth muscle cells (SMCs), the present study was conducted to evaluate the effects of BaP on DNA synthesis and protooncogene expression in rat aortic SMCs. Subcultured cells were exposed to BaP (0.3-30 microM) for various times and processed for measurements of [3H]thymidine incorporation and c-Ha-ras or c-myc protooncogene expression. Sucrose density gradient analysis and gel mobility shift assays were employed to assess binding of BaP to intracellular proteins in the nuclear fraction and their interaction with a synthetic dioxin responsive element (DRE), respectively. BaP (0.3 and 3 microM) increased DNA synthetic rates in randomly cycling SMCs in a concentration- and time-dependent fashion. Increased DNA synthesis was also observed in synchronized SMCs treated with 3.0 microM BaP. Challenge of quiescent SMCs with 10% fetal bovine serum in the presence of BaP for 8 h enhanced serum-induced c-Ha-ras and c-myc protooncogene expression. Velocity sedimentation analysis of the nuclear fraction from SMCs treated with 0.3 microM [3H]BaP resulted in specifically bound peaks of 4.4 S and 6.5 S. The 6.5 S peak was competitively inhibited in the presence of unlabeled 10 microM 2,3,7,8-tetrachlorodibenzofuran, an aryl hydrocarbon ligand, while both peaks were eliminated in cells cotreated with 10 microM alpha-naphthoflavone (alpha-NF), an inhibitor of cytochrome P450 and an antagonist of PAH-protein interactions. alpha-NF also inhibited the induction of c-Ha-ras mRNA and DNA synthesis by BaP and the binding of BaP-Ah receptor complexes to the DRE. These results show that BaP enhances serum-induced protooncogene expression during the early part of the cell cycle in rat aortic SMCs and suggest that binding of BaP to intracellular proteins may play a role in these responses.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0003-9861
pubmed:author
pubmed:issnType
Print
pubmed:volume
300
pubmed:geneSymbol
c-Ha-ras, c-myc
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
124-31
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:8424644-Animals, pubmed-meshheading:8424644-Aorta, Thoracic, pubmed-meshheading:8424644-Base Sequence, pubmed-meshheading:8424644-Benzo(a)pyrene, pubmed-meshheading:8424644-Cell Nucleus, pubmed-meshheading:8424644-Cell Survival, pubmed-meshheading:8424644-Cells, Cultured, pubmed-meshheading:8424644-DNA Replication, pubmed-meshheading:8424644-Exons, pubmed-meshheading:8424644-Gene Expression, pubmed-meshheading:8424644-Gene Expression Regulation, pubmed-meshheading:8424644-Genes, myc, pubmed-meshheading:8424644-Genes, ras, pubmed-meshheading:8424644-Humans, pubmed-meshheading:8424644-Kinetics, pubmed-meshheading:8424644-Molecular Sequence Data, pubmed-meshheading:8424644-Muscle, Smooth, Vascular, pubmed-meshheading:8424644-Oligodeoxyribonucleotides, pubmed-meshheading:8424644-Protein Binding, pubmed-meshheading:8424644-Proto-Oncogenes, pubmed-meshheading:8424644-RNA, Messenger, pubmed-meshheading:8424644-Rats, pubmed-meshheading:8424644-Thymidine, pubmed-meshheading:8424644-Time Factors
pubmed:year
1993
pubmed:articleTitle
Modulation of protooncogene expression in rat aortic smooth muscle cells by benzo[a]pyrene.
pubmed:affiliation
Department of Veterinary Physiology and Pharmacology, Texas A & M University, College Station 77843.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.