Retinoblastoma protein family in cell cycle and cancer: a review

J Cell Biochem. 1996 Sep 1;62(3):418-30. doi: 10.1002/(SICI)1097-4644(199609)62:3%3C418::AID-JCB12%3E3.0.CO;2-E.


Two genes, p107 and Rb2/p130, are strictly related to RB, the most investigated tumor suppressor gene, responsible for susceptibility to retinoblastoma. The products of these three genes, namely pRb, p107, and pRb2/p130 are characterized by a peculiar steric conformation, called "pocket," responsible for most of the functional interactions characterizing the activity of these proteins in the homeostasis of the cell cycle. The interest in these genes and proteins springs from their ability to regulate cell cycle processes negatively, being able, for example, to dramatically slow down neoplastic growth. So far, among these genes, only RB is firmly established to act as a tumor suppressor, because its lack-of-function is clearly involved in tumor onset and progression. It has been found deleted or mutated in most retinoblastomas and sarcomas, but its inactivation is likely to play a crucial role in other types of human cancers. The two other members of the family have been discovered more recently and are currently under extensive investigation. We review analogies and differences among the pocket protein family members, in an attempt to understand their functions in normal and cancer cells.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.
  • Review

MeSH terms

  • Cell Cycle / genetics*
  • Disease Progression
  • Gene Expression Regulation, Developmental
  • Genes, Tumor Suppressor
  • Humans
  • Neoplasms / genetics*
  • Neoplasms / metabolism
  • Nuclear Proteins / genetics
  • Oncogene Proteins / metabolism
  • Phosphoproteins / genetics
  • Protein Processing, Post-Translational
  • Proteins*
  • Retinoblastoma Protein / physiology*
  • Retinoblastoma-Like Protein p107
  • Retinoblastoma-Like Protein p130


  • Nuclear Proteins
  • Oncogene Proteins
  • Phosphoproteins
  • Proteins
  • RBL1 protein, human
  • RBL2 protein, human
  • Retinoblastoma Protein
  • Retinoblastoma-Like Protein p107
  • Retinoblastoma-Like Protein p130