GSK-3? regulates cell growth, migration, and angiogenesis via Fbw7 and USP28-dependent degradation of HIF-1?.

ABSTRACT: The hypoxia-inducible transcription factor-1? (HIF-1?) is a major regulator of angiogenesis, carcinogenesis, and various processes by which cells adapt to hypoxic conditions. Therefore, the identification of critical players regulating HIF-1? is not only important for the understanding of angiogenesis and different cancer phenotypes, but also for unraveling new therapeutic options. We report a novel mechanism by which HIF-1? is degraded after glycogen synthase kinase-3 (GSK-3)-induced phosphorylation and recruitment of the ubiquitin ligase and tumor suppressor F-box and WD protein Fbw7. Further, experiments with GSK-3? and Fbw7-deficient cells revealed that GSK-3? and Fbw7-dependent HIF-1? degradation can be antagonized by ubiquitin-specific protease 28 (USP28). In agreement with this, Fbw7 and USP28 reciprocally regulated cell migration and angiogenesis in an HIF-1?-dependent manner. Therefore, we have identified a new pathway that could be targeted at the level of GSK-3, Fbw7, or USP28 to influence HIF-1?-dependent processes like angiogenesis and metastasis.

SUBMITTER: Flugel D 

PROVIDER: S-EPMC3352078 | biostudies-literature | 2012 Feb

REPOSITORIES: biostudies-literature