A prostatic intraepithelial neoplasia-dependent p27 Kip1 checkpoint induces senescence and inhibits cell proliferation and cancer progression

Cancer Cell. 2008 Aug 12;14(2):146-55. doi: 10.1016/j.ccr.2008.06.002.


Transgenic expression of activated AKT1 in the murine prostate induces prostatic intraepithelial neoplasia (PIN) that does not progress to invasive prostate cancer (CaP). In luminal epithelial cells of Akt-driven PIN, we show the concomitant induction of p27(Kip1) and senescence. Genetic ablation of p27(Kip1) led to downregulation of senescence markers and progression to cancer. In humans, p27(Kip1) and senescence markers were elevated in PIN not associated with CaP but were decreased or absent, respectively, in cancer-associated PIN and in CaP. Importantly, p27(Kip1) upregulation in mouse and human in situ lesions did not depend upon mTOR or Akt activation but was instead specifically associated with alterations in cell polarity, architecture, and adhesion molecules. These data suggest that a p27(Kip1)-driven checkpoint limits progression of PIN to CaP.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alleles
  • Animals
  • Animals, Genetically Modified
  • Biomarkers / metabolism
  • Cell Adhesion
  • Cell Communication
  • Cell Line
  • Cell Polarity
  • Cell Proliferation
  • Cellular Senescence*
  • Cyclin-Dependent Kinase Inhibitor p27 / metabolism*
  • Disease Progression
  • Epithelial Cells / pathology
  • Humans
  • Male
  • Mice
  • Mutation / genetics
  • Phenotype
  • Prostatic Intraepithelial Neoplasia / metabolism*
  • Prostatic Intraepithelial Neoplasia / pathology*
  • Prostatic Neoplasms / metabolism*
  • Prostatic Neoplasms / pathology*
  • Protein Kinases / metabolism
  • Proto-Oncogene Proteins c-akt / metabolism
  • Rats
  • TOR Serine-Threonine Kinases


  • Biomarkers
  • Cyclin-Dependent Kinase Inhibitor p27
  • Protein Kinases
  • MTOR protein, human
  • TOR Serine-Threonine Kinases
  • mTOR protein, mouse
  • Akt1 protein, mouse
  • Proto-Oncogene Proteins c-akt