B-MYB is required for recovery from the DNA damage-induced G2 checkpoint in p53 mutant cells

Cancer Res. 2009 May 1;69(9):4073-80. doi: 10.1158/0008-5472.CAN-08-4156. Epub 2009 Apr 21.

Abstract

In response to DNA damage, several signaling pathways that arrest the cell cycle in G(1) and G(2) are activated. The down-regulation of mitotic genes contributes to the stable maintenance of the G(2) arrest. The human LINC or DREAM complex, together with the B-MYB transcription factor, plays an essential role in the expression of G(2)-M genes. Here, we show that DNA damage results in the p53-dependent binding of p130 and E2F4 to LINC and the dissociation of B-MYB from LINC. We find that B-MYB fails to dissociate from LINC in p53 mutant cells, that this contributes to increased G(2)-M gene expression in response to DNA damage in these cells, and, importantly, that B-MYB is required for recovery from the G(2) DNA damage checkpoint in p53-negative cells. Reanalysis of microarray expression data sets revealed that high levels of B-MYB correlate with a p53 mutant status and an advanced tumor stage in primary human breast cancer. Taken together, these data suggest that B-MYB/LINC plays an important role in the DNA damage response downstream of p53.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Breast Neoplasms / genetics
  • Breast Neoplasms / metabolism
  • Breast Neoplasms / pathology
  • Cell Cycle Proteins / genetics
  • Cell Cycle Proteins / metabolism*
  • Cell Line, Tumor
  • Crk-Associated Substrate Protein / metabolism
  • DNA Damage*
  • Doxorubicin / pharmacology
  • G2 Phase / genetics
  • HCT116 Cells
  • Humans
  • Kv Channel-Interacting Proteins / metabolism
  • Mutation*
  • Nuclear Proteins / metabolism
  • Protein Binding
  • Repressor Proteins / metabolism
  • Trans-Activators / genetics
  • Trans-Activators / metabolism*
  • Tumor Suppressor Protein p53 / genetics
  • Tumor Suppressor Protein p53 / metabolism*
  • Tumor Suppressor Proteins / metabolism

Substances

  • BCAR1 protein, human
  • Cell Cycle Proteins
  • Crk-Associated Substrate Protein
  • KCNIP3 protein, human
  • Kv Channel-Interacting Proteins
  • LIN9 protein, human
  • MYBL2 protein, human
  • Nuclear Proteins
  • Repressor Proteins
  • TP53 protein, human
  • Trans-Activators
  • Tumor Suppressor Protein p53
  • Tumor Suppressor Proteins
  • Doxorubicin