p63 regulates an adhesion programme and cell survival in epithelial cells

Department of Cell Biology, Harvard Medical School, 240 Longwood Ave, Boston, MA 02115, USA.
Nature Cell Biology (Impact Factor: 20.06). 05/2006; 8(6):551-561. DOI: 10.1038/ncb1420
Source: PubMed

ABSTRACT p63 is critical for epithelial development yet little is known about the transcriptional programmes it regulates. By characterising transcriptional changes and cellular effects following modulation of p63 expression, we have defined a vital role for p63 in cellular adhesion. Knockdown of p63 expression caused downregulation of cell adhesion-associated genes, cell detachment and anoikis in mammary epithelial cells and keratinocytes. Conversely, overexpression of the TAp63 or Np63 isoforms of p63 upregulated cell adhesion molecules, increased cellular adhesion and conferred resistance to anoikis. Apoptosis induced by loss of p63 was rescued by signalling downstream of 4 integrin. Our results implicate p63 as a key regulator of cellular adhesion and survival in basal cells of the mammary gland and other stratified epithelial tissues.

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