The Role of AhR in Breast Cancer Development
Abstract
The aryl hydrocarbon receptor (AhR) is an environmental carcinogen-activated transcription factor associated with tumorigenesis. Little is known of the transcriptional consequences of constitutive AhR activation. The effects of constitutively active and environmental ligand-induced AhR on c-myc, an oncogene, were investigated. Results indicate that: (1) the AhR constitutively binds the c-myc promoter; (2) there is a low but significant baseline level of c-myc promoter activity, which is not regulated by NF-kappaB and is not affected by an environmental AhR ligand; (3) deletion of any one of the AhREs has no effect on constitutive reporter activity, while deletion of all six increases reporter activity approximately fivefold; (4) a similar increase in reporter activity occurs when constitutively active AhR is suppressed by transfection with an AhR repressor plasmid (AhRR); (5) AhRR transfection significantly increases background levels of endogenous c-myc mRNA and c-Myc protein. These results suggest that the AhR influences the expression of c-Myc, a protein critical to malignant transformation.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 2006
- Accession Number
- ADA460071
Entities
People
- Xinhai Yang
Organizations
- Boston University