What (H)IF isoform matters? A deubiquitinase can tune the hypoxic response
1Division of Translational Cancer Research, Department of Laboratory Medicine, Lund University, Lund, Sweden.
The EMBO Journal
|February 24, 2022
Abstract:
Context-specific control mechanisms of hypoxia-inducible transcription factors HIF-1alpha and HIF-2alpha in tumors exposed to oxygen shortage remain incompletely understood. In this issue, Zhang et al (2022) identify a deubiquitinase that differentially stabilizes HIF-2alpha in stem-like glioblastoma cells, suggesting potential implications for regulation of the hypoxic response in a wide array of tissues and cancers.
Insights
Researchers discovered a deubiquitinase enzyme that specifically stabilizes hypoxia-inducible factor 2-alpha (HIF-2alpha) in glioblastoma stem cells. This finding sheds light on how tumors adapt to oxygen deprivation and may impact cancer treatment strategies.
Area of Science:
- Oncology
- Molecular Biology
- Biochemistry
Background:
- Hypoxia-inducible factors (HIFs) are key regulators of cellular response to low oxygen conditions.
- HIF-1alpha and HIF-2alpha play critical roles in tumor growth, angiogenesis, and metastasis.
- The precise regulatory mechanisms controlling HIF-1alpha and HIF-2alpha stability in cancer remain incompletely understood.
Purpose of the Study:
- To investigate the context-specific mechanisms controlling HIF-1alpha and HIF-2alpha stability in tumors.
- To identify novel regulators of the hypoxic response in cancer cells.
Main Methods:
- Utilized glioblastoma stem-like cell models.
- Employed biochemical assays to identify and characterize deubiquitinase activity.
- Investigated the differential stabilization of HIF-2alpha.
Main Results:
- Identified a specific deubiquitinase enzyme.
- Demonstrated that this enzyme differentially stabilizes HIF-2alpha in glioblastoma stem-like cells.
- This stabilization is linked to the hypoxic response.
Conclusions:
- The identified deubiquitinase plays a crucial role in regulating HIF-2alpha stability in a context-specific manner.
- This finding has potential implications for understanding and targeting the hypoxic response in various cancers.
- Further research may reveal therapeutic strategies targeting this pathway.
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