14-3-3σ and p21 synergize to determine DNA damage response following Chk2 inhibition Journal Article


Authors: Meng, S.; Arbit, T.; Veeriah, S.; Mellinghoff, I. K.; Fang, F.; Vivanco, I.; Rohle, D.; Chan, T. A.
Article Title: 14-3-3σ and p21 synergize to determine DNA damage response following Chk2 inhibition
Abstract: DNA damage checkpoints are critical for preventing tumorigenesis and regulating the response of cells to genotoxic agents. It is believed that the coordinated actions of a number of effectors underlie proper checkpoint function. The kinase Chk2, p21 and 14-3-3σ have each been shown to be independent effectors of the G<sub>2</sub> DNA damage checkpoint. However, the relative roles of these proteins remain unclear. To help elucidate this question, we have perturbed each of these 3 genes in combination in human cells. We show that Chk2 depletion causes markedly increased sensitivity to DNA damage in p21<sup>-/-</sup>, 14-3-3σ<sup>-/-</sup> cells but not in cells lacking only one or none of these genes. This greater sensitivity was due to an increase in apoptosis following DNA damage and not due to exacerbation of G <sub>2</sub> checkpoint defects. Pharmacologic inhibition of Chk2 in p21 <sup>-/-</sup>, 14-3-3σ<sup>-/-</sup> cells also resulted in greater sensitivity to DNA damage. Our data indicates that p21 and 14-3-3σ synergize as molecular determinants of sensitivity to DNA damage following Chk2 inhibition, and Chk2 modulates the biological rheostat that determines whether a cancer cell undergoes arrest versus death after treatment with a chemotherapeutic agent. These findings have implications for the targeting of Chk2 in human cancers. ©2009 Landes Bioscience.
Keywords: controlled study; dna binding protein; human cell; genetics; dna-binding proteins; doxorubicin; sensitivity analysis; cell cycle protein; metabolism; cell cycle proteins; cell death; dna damage; dna repair; apoptosis; enzyme inhibition; protein depletion; protein protein interaction; neoplasm proteins; tumor markers, biological; rna interference; cell line, tumor; protein serine threonine kinase; protein p53; tumor marker; drug antagonism; protein-serine-threonine kinases; cancer cell; tumor suppressor proteins; tumor protein; tumor cell line; atm protein; tumor suppressor protein p53; cell cycle arrest; checkpoint kinase 2; cell cycle g2 phase; gene silencing; cyclin dependent kinase inhibitor 1a; cyclin-dependent kinase inhibitor p21; exonuclease; antibiotics, antineoplastic; tumor suppressor protein; antineoplastic antibiotic; protein p21; atr protein, human; gene knockdown techniques; p21; checkpoint; stratifin; sfn protein, human; exonucleases; g2 phase
Journal Title: Cell Cycle
Volume: 8
Issue: 14
ISSN: 1538-4101
Publisher: Taylor & Francis Inc.  
Date Published: 2009-07-15
Start Page: 2238
End Page: 2246
Language: English
PUBMED: 19502805
PROVIDER: scopus
DOI: 10.4161/cc.8.14.8998
DOI/URL:
Notes: --- - "Export Date: 30 November 2010" - "Source: Scopus"
Altmetric Score
MSK Authors
  1. Timothy Chan
    222 Chan
  2. Fang Fang
    6 Fang
  3. Igor Vivanco
    12 Vivanco
  4. Daniel A Rohle
    14 Rohle
  5. Shasha Meng
    4 Meng
  6. Tali Chava Arbit
    1 Arbit