Format

Send to

Choose Destination
See comment in PubMed Commons below
Oncogene. 2003 Jun 5;22(23):3624-34.

Mutant p53 and aberrant cytosine methylation cooperate to silence gene expression.

Author information

1
Bone Marrow Transplant Program, Arizona Cancer Center and Department of Pharmacology & Toxicology, The University of Arizona, Tucson, AZ 85724, USA.

Abstract

p53 is an important transcriptional regulator that is frequently mutated in cancer. Gene-profiling experiments of breast cancer cells infected with wt p53 revealed both MASPIN and desmocollin 3 (DSC3) to be p53-target genes, even though both genes are silenced in association with aberrant cytosine methylation of their promoters. Despite the transcriptional repression of these genes by aberrant DNA methylation, restoration of p53 resulted in the partial reactivation of both genes. This reactivation is a result of wt p53 binding to its consensus DNA-binding sites within the MASPIN and DSC3 promoters, stimulating histone acetylation, and enhancing chromatin accessibility of their promoters. Interestingly, wt p53 alone did not affect the methylation status of either promoter, suggesting that p53 itself can partially overcome the repressive barrier of DNA methylation. Pharmacologic inhibition of DNA methylation with 5-aza-2'-deoxycytidine in combination with restoration of wt p53 status resulted in a synergistic reactivation of these genes to near-normal levels. These results suggest that cancer treatments that target both genetic and epigenetic facets of gene regulation may be a useful strategy towards the therapeutic transcriptional reprogramming of cancer cells.

PMID:
12789271
DOI:
10.1038/sj.onc.1206545
[Indexed for MEDLINE]
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Nature Publishing Group
    Loading ...
    Support Center