Format

Send to:

Choose Destination
See comment in PubMed Commons below
Cell. 2004 Apr 16;117(2):225-37.

IkappaB kinase promotes tumorigenesis through inhibition of forkhead FOXO3a.

Author information

  • 1Department of Molecular and Cellular Oncology, The University of Texas, Houston, TX 77030, USA. michu@mdanderson.org

Erratum in

  • Cell. 2007 Jun 29;129(7):1427-8.

Abstract

Nuclear exclusion of the forkhead transcription factor FOXO3a by protein kinase Akt contributes to cell survival. We investigated the pathological relationship between phosphoylated-Akt (Akt-p) and FOXO3a in primary tumors. Surprisingly, FOXO3a was found to be excluded from the nuclei of some tumors lacking Akt-p, suggesting an Akt-independent mechanism of regulating FOXO3a localization. We provide evidence for such a mechanism by showing that IkappaB kinase (IKK) physically interacts with, phosphorylates, and inhibits FOXO3a independent of Akt and causes proteolysis of FOXO3a via the Ub-dependent proteasome pathway. Cytoplasmic FOXO3a correlates with expression of IKKbeta or Akt-p in many tumors and associates with poor survival in breast cancer. Further, constitutive expression of IKKbeta promotes cell proliferation and tumorigenesis that can be overridden by FOXO3a. These results suggest the negative regulation of FOXO factors by IKK as a key mechanism for promoting cell growth and tumorigenesis.

PMID:
15084260
[PubMed - indexed for MEDLINE]
Free full text

Publication Types, MeSH Terms, Substances, Grant Support

Publication Types

MeSH Terms

Substances

Grant Support

PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Elsevier Science
    Loading ...
    Write to the Help Desk