• Register
Forgot Password

If you have forgotten your password you can enter your email here and get a temporary password sent to your email.


Leaving Community

Are you sure you want to leave this community? Leaving the community will revoke any permissions you have been granted in this community.


Topological control of p21WAF1/CIP1 expression in normal and neoplastic tissues.

The p53-regulated gene product p21WAF1/CIP1 is the prototype of a family of small proteins that negatively regulate the cell cycle. To learn more about p21WAF1/CIP1 regulation in vivo, monoclonal antibodies were developed for immunohistochemistry. These revealed that p21WAF1/CIP1 expression followed radiation-induced DNA damage in human skin in a pattern consistent with its regulation by p53. A detailed comparison of the human, rat, and mouse p21WAF1/CIP1 promoter sequences revealed that this induction was probably mediated by conserved p53-binding sites upstream of the transcription start site. In unirradiated tissues, p21WAF1/CIP1 expression was apparently independent of p53 and was observed in a variety of cell types. Moreover, there was a striking compartmentalization of p21WAF1/CIP1 expression throughout the gastrointestinal tract that correlated with proliferation rather than differentiation. As epithelial cells migrated up the crypts, the Ki67-expressing proliferating compartment near the crypt base ended abruptly, with the coincident appearance of a nonproliferating compartment expressing p21WAF1/CIP1. In colonic neoplasms, this distinct compartmentalization was largely abrogated. Cell cycle inhibitors are thus subject to precise topological control, and escape from this regulation may be a critical feature of neoplastic transformation.

Pubmed ID: 7796420


  • el-Deiry WS
  • Tokino T
  • Waldman T
  • Oliner JD
  • Velculescu VE
  • Burrell M
  • Hill DE
  • Healy E
  • Rees JL
  • Hamilton SR


Cancer research

Publication Data

July 1, 1995

Associated Grants

  • Agency: NCI NIH HHS, Id: CA43460
  • Agency: NCI NIH HHS, Id: CA62924
  • Agency: NIGMS NIH HHS, Id: GM07184

Mesh Terms

  • Adenoma
  • Animals
  • Antibodies, Monoclonal
  • Base Sequence
  • Carcinoma
  • Colorectal Neoplasms
  • Cyclin-Dependent Kinase Inhibitor p21
  • Cyclins
  • DNA Primers
  • Female
  • Gene Expression Regulation, Neoplastic
  • Humans
  • Immunoenzyme Techniques
  • Male
  • Mice
  • Mice, Inbred BALB C
  • Mice, Inbred C57BL
  • Molecular Sequence Data
  • Promoter Regions, Genetic
  • RNA, Messenger
  • Rats
  • Sequence Alignment
  • Sequence Homology, Nucleic Acid
  • Skin
  • Transcription, Genetic
  • Tumor Suppressor Protein p53