OTX1 expression in breast cancer is regulated by p53

Oncogene. 2011 Jul 7;30(27):3096-103. doi: 10.1038/onc.2011.31. Epub 2011 Apr 11.

Abstract

The p53 transcription factor has a critical role in cell stress response and in tumor suppression. Wild-type p53 protein is a growth modulator and its inactivation is a critical event in malignant transformation. It has been recently demonstrated that wild-type p53 has developmental and differentiation functions. Indeed an over-expression of p53 in tumor cells induces asymmetrical division avoiding self-renewal of cancer stem cells (CSCs) and instead promoting their differentiation. In this study, 28 human breast carcinomas have been analyzed for expression of wild-type p53 and of a pool of non-clustered homeobox genes. We demonstrated that orthodenticle homolog 1 gene (OTX1) is transcribed in breast cancer. We established that the p53 protein directly induces OTX1 expression by acting on its promoter. OTX1 has been described as a critical molecule for axon refinement in the developing cerebral cortex of mice, and its activity in breast cancer suggests a synergistic function with p53 in CSC differentiation. Wild-type p53 may regulate cellular differentiation by an alternative pathway controlling OTX1 signaling only in breast cancer cells and not in physiological conditions.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Breast Neoplasms / genetics
  • Breast Neoplasms / metabolism*
  • Female
  • Gene Expression Regulation, Neoplastic / physiology*
  • Humans
  • Otx Transcription Factors / genetics*
  • Tumor Suppressor Protein p53 / physiology*

Substances

  • OTX1 protein, human
  • Otx Transcription Factors
  • Tumor Suppressor Protein p53