Our findings elucidate a mechanism whereby LSD1 controls senescence in Glioblastoma tumor cells through the regulation of HIF-1α, and we propose the novel defined LSD1/HIF-1α axis as a new target for the therapy of Glioblastoma tumors.
By promoting the adaptation to non-adherent conditions, mechanisms driven by HIF-1α may considerably contribute to the biology and aggressiveness of glioblastoma.
Hypoxia plays important roles in the prognosis of malignant brain tumors such as glioblastoma because it causes drug delivery deficiencies and the induction of hypoxia-inducible factor-1α in tumor cells.
The HIF‑1α/miR‑224‑3p/ATG5 axis affects cell mobility and chemosensitivity by regulating hypoxia‑induced protective autophagy in glioblastoma and astrocytoma.
While HIF1α has been widely studied in cancer, HIF2α offers a potentially more specific and appealing target in glioblastoma given expression in glioma stem cells and not normal neural progenitors, activation in states of chronic hypoxia and expression that correlates with glioma patient survival.
Therefore, our findings uncover a hypoxia-induced negative feedback mechanism that maintains high activity of HIF-1 and cell mobility in human glioblastoma.
The findings of the current study demonstrate presence of the IDH1 R132H mutation in primary human glioblastoma cell lines with upregulated HIF-1α expression, downregulating c-MYC activity and resulting in a consequential decrease in miR-20a, which is responsible for cell proliferation and resistance to standard temozolomide treatment.
The aforementioned results demonstrate that hypoxia could induce enhancements of migration and invasion by activating PI3K/Akt/mTOR pathway by targeting HIF-1α in human glioblastoma U87 cells, which provide a theoretical basis for the treatments of GBM by targeting the PI3K/Akt/mTOR/HIF-1α pathway.
Clinical positron emission tomography studies using radiolabeled Cu-ATSM have shown that Cu-ATSM accumulates in glioblastoma and its uptake is associated with high hypoxia-inducible factor-1α expression.
Furthermore, the liposomes made better modulation of glioblastoma microenvironment such as the down-regulation of CD31-positive tumor vessels and HIF-1α expression.
Taken together, these results suggest that DT at clinically achievable concentration functions as an inhibitor of HIF-1α, worthy of further investigations in the therapy of glioblastoma.
Under hypoxic conditions, HIF-1α protein levels in the glioblastoma cell lines increased, primarily localizing into the nucleus similar to glioblastoma tissues.
Because hypoxia-inducible factor 1α (HIF-1α) is the major mediator of hypoxia-regulated cellular control, inhibition of this transcription factor may reduce glioblastoma growth.
Focusing on inhibiting the signaling pathways, which are associated with hypoxia-mediated maintenance of glioblastoma stem cells or the knockdown of the hypoxia-inducible factor 1-alpha (HIF1α), may help to the develop new target-specific treatments.
The expression levels of LOX, BMP1 and HIF1A were correlated and analyzed according to IDH1 mutation status and to the clinical end-point of overall survival of glioblastoma patients.
Reduced PDH activity in U87 glioblastoma and NHA IDH1 mutant cells was associated with relative increases in PDH inhibitory phosphorylation, expression of pyruvate dehydrogenase kinase-3, and levels of hypoxia inducible factor-1α.