TRIM25 Promotes Glioma Progression by Stabilizing HIF-1a Expression in Normoxia through K11/K29 Polyubiquitination

The malignant progression of glioblastoma (GBM) involves complex regulatory mechanisms, complicating its clinical treatment. Tumors exhibit a hypoxic molecular phenotype thought to promote malignant tumor progression; however, the mechanism in GBMs is still unclear. This study reports for the first time that GBM cells exhibit a hypoxic phenotype and highly express hypoxia-inducible factor (HIF)-1a under normoxic conditions; in addition, the E3 ubiquitin ligase TRIM25, which is abnormally expressed in GBM cells under aerobic conditions, binds to the N-terminal peptide of HIF-1a through the RING domain.