Mechanisms of p53-Mediated Apoptosis

Abstract

The p53 tumor suppressor is the most commonly mutated gene in human breast cancer. Upon genotoxic stress, p53, a sequence-specific transcription factor, induces target genes that mediate many cellular activities such as cell cycle arrest and apoptosis. While the mechanism by which p53 induces apoptosis is unclear, this pathway has rich potential as a target for cancer therapies. Thus, the purpose, of this proposal is to characterize the molecular basis of p53- mediated apoptosis by characterizing the transcriptional regulation of IGFBP3, a pro-apoptotic target gene of p53, and by characterizing the role of IGFBP3 in p53-dependent apoptosis. To date, I have found that the N-terminal transcriptional activation domain 1 (AD1) and the C-terminal basic domain (BD) of p53 is inhibitory, while activation domain 2 (AD2) is required for transactivation of IGFBP3 by p53. Interestingly, lack of AD1 and the BD is paralleled in nature, and the naturally occurring p53 isoforms activate the IGFBP3 promoter. In addition, inhibition of histone deacetylase activity restores the induction of IGFBP3 by full length p53. Since histone deacetylase (HDAC) inhibitors are in clinical trials for cancer therapies, my results shed insight into how HDAC inhibitors may be used as breast cancer therapies.

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Document Details

Document Type
Technical Report
Publication Date
Mar 01, 2006
Accession Number
ADA456010

Entities

People

  • Kelly L. Mcnaughton-harms

Organizations

  • University of Alabama

Tags

DTIC Thesaurus Topics

  • Amino Acids
  • Apoptosis
  • Breast Cancer
  • Carrier Proteins
  • Cell Line
  • Cell Physiological Processes
  • Chemistry
  • Enzyme Inhibitors
  • Gene Expression
  • Growth Factors
  • Inhibition
  • Inhibitors
  • Molecules
  • Neoplasms
  • Proteins
  • Therapy
  • Transcription Factors

Fields of Study

  • Biology

Readers

  • Molecular Biology and Genetics