Mutant versions of von Hippel-Lindau (VHL) can protect HIF1? from SART1-mediated degradation in clear-cell renal cell carcinoma
- Authors
- Ort?z de Land?zuri, Manuel
- Format
- Article
- Status
- publishedVersion
- Description
Inactivation of the von Hippel-Lindau (VHL) tumor suppressor drives the development of clear-cell renal cell carcinoma (ccRCC) through hypoxia-inducible factors (HIFs). Although ccRCC cells exhibit constitutive normoxic HIF signaling, the potential role of hypoxia in this setting is not fully understood. We show here that the ccRCC cell lines RCC4 and RCC10, which express mutant versions of VHL, have reduced HIF1? expression in hypoxia, whereas HIF2? expression is increased or not affected. Similar findings were observed in normoxia after abrogation of prolyl hydroxylase activity by siRNA or pharmacological inhibition, and by siRNA inhibition of mutant VHL. This reduction of HIF1? protein is due to proteasome-dependent degradation and is mediated by the E3 ubiquitin ligase SART1. HIF1? degradation favors ccRCC proliferation, in line with the previously recognized tumor suppressor capability of HIF1?. Our data indicate that mutant VHL can protect HIF1? from SART1-dependent degradation in normoxic conditions, but this protection is lost in hypoxic settings, favoring hypoxia-dependent ccRCC proliferation. This mechanism of HIF1? degradation might operate in some VHL-related clear-cell renal carcinomas in which the deletion of HIF1? locus does not occur.
https://www.ncbi.nlm.nih.gov/pubmed/25915846
- Publication Year
- 2016
- Language
- eng
- Topic
- VON HIPPEL-LINDAU (VHL)
HIF1?
SART1-MEDIATED DEGRADATION
RENAL CELL CARCINOMA
- Repository
- Repositorio SENESCYT
- Rights
- openAccess
- License
- closedAccess