Regulating the p53 pathway: in vitro hypotheses, in vivo veritas

Nat Rev Cancer. 2006 Dec;6(12):909-23. doi: 10.1038/nrc2012.


Mutations in TP53, the gene that encodes the tumour suppressor p53, are found in 50% of human cancers, and increased levels of its negative regulators MDM2 and MDM4 (also known as MDMX) downregulate p53 function in many of the rest. Understanding p53 regulation remains a crucial goal to design broadly applicable anticancer strategies based on this pathway. This Review of in vitro studies, human tumour data and recent mouse models shows that p53 post-translational modifications have modulatory roles, and MDM2 and MDM4 have more profound roles for regulating p53. Importantly, MDM4 emerges as an independent target for drug development, as its inactivation is crucial for full p53 activation.

Publication types

  • Review

MeSH terms

  • Animals
  • Antineoplastic Agents / pharmacology
  • Cell Cycle Proteins
  • Cell Transformation, Neoplastic / genetics
  • Cell Transformation, Neoplastic / metabolism
  • Gene Expression Regulation, Neoplastic
  • Humans
  • Mice
  • Mutation
  • Neoplasms, Experimental / genetics
  • Neoplasms, Experimental / metabolism
  • Nuclear Proteins / antagonists & inhibitors
  • Nuclear Proteins / metabolism*
  • Protein Modification, Translational*
  • Proto-Oncogene Proteins / antagonists & inhibitors
  • Proto-Oncogene Proteins / metabolism*
  • Proto-Oncogene Proteins c-mdm2 / antagonists & inhibitors
  • Proto-Oncogene Proteins c-mdm2 / metabolism*
  • Transcription, Genetic
  • Tumor Suppressor Protein p53 / genetics*
  • Tumor Suppressor Protein p53 / metabolism*
  • Ubiquitin-Protein Ligases / antagonists & inhibitors
  • Ubiquitin-Protein Ligases / metabolism*


  • Antineoplastic Agents
  • Cell Cycle Proteins
  • MDM4 protein, human
  • Mdm4 protein, mouse
  • Nuclear Proteins
  • Proto-Oncogene Proteins
  • Tumor Suppressor Protein p53
  • Proto-Oncogene Proteins c-mdm2
  • Ubiquitin-Protein Ligases