Binding and phosphorylation of par-4 by akt is essential for cancer cell survival

A1 Journal article (refereed)


Internal Authors/Editors


Publication Details

List of Authors: Goswami, Burikhanov, de Thonel, Fujita, Goswami, Zhao, Eriksson, Tsuruo, Rangnekar
Publication year: 2005
Journal: Molecular Cell
Journal acronym: Mol Cell
Volume number: 20
Issue number: 1
Start page: 33
End page: 44
ISSN: 1097-2765
eISSN: 1097-4164


Abstract

Activation of the PI3K-Akt pathway by loss of tumor suppressor PTEN (phosphatase and tensin homolog deleted on chromosome 10) function, increased growth factor signaling, or oncogene expression renders cancer cells resistant to apoptotic signals and promotes tumor growth. Although Akt acts as a global survival signal, the molecular circuits of this pathway have not been completely established. We report that Akt physically binds to the pro-apoptotic protein Par-4 via the Par-4 leucine zipper domain and phosphorylates Par-4 to inhibit apoptosis. Suppression of Akt activation by the PI3K-inhibitor PTEN or LY294002, Akt expression by RNA-interference, or Akt function by dominant-negative Akt caused apoptosis in cancer cells. Apoptosis induced by inhibiting Akt was blocked by inhibition of Par-4 expression, but not by inhibition of other apoptosis agonists that are Akt substrates, suggesting that inhibition of the PI3K-Akt pathway leads to Par-4-dependent apoptosis. Thus, Par-4 is essential for PTEN-inducible apoptosis, and inactivation of Par-4 by Akt promotes cancer cell survival.

Last updated on 2019-17-11 at 05:17