The Influence of Estrogen on Breast Cancer Cell Proliferation
Abstract
Estrogen affects both the cytoskeletal and chromatin structure of breast cancer cells. The treatment of breast cancer cells with 10 nM estradiol causes the estrogen receptor to recruit histone acetyltransferases to the promoter of the estrogen-responsive PS2 gene within 60 min, while exposure to estrogen for 72 h increases the levels of DNA-associated cytokeratins. To determine the effect of estrogen on regions downstream of estrogen- responsive promoters, quantitative PCR was performed on DNA isolated from chromatin immunoprecipitations using anti-acetylated 113 and H4 antibodies. Treatment with 10 nM estradiol induced a transient state of 113 and 114 acetylation along the PS2 promoter, exon 2, and exon 3, that was maximal after 60-120 min. After three hours, this hyperacetylation decreased to levels above those observed along the PS2 gene in untreated MCF-7 cells. To determine how estrogen influences DNA-associated cytokeratins, the levels of total, intermediate filament-assembled and DNA-associated cytokeratins were determined by Western Blotting and two dimension gel electrophoresis. The level of DNA-associated cytokeratins increased after 2 h of 10 nM estradiol treatment, while the levels of total and filament cytokeratins remained the same. This suggests that early estrogen exposure (i.e. 2 h) promotes interactions between cytokeratins and DNA.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 2002
- Accession Number
- ADB284135
Entities
People
- J. R. Davie
- Virginia A. Spencer
Organizations
- University of Manitoba