The phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway is over-activated in glioblastoma and has been revealed to be potentially implicated in resistance to TMZ.
Insulin growth factor-2 binding protein 3 (IGF2BP3) is a glioblastoma-specific marker that activates phosphatidylinositol 3-kinase/mitogen-activated protein kinase (PI3K/MAPK) pathways by modulating IGF-2.
Taken together, these findings suggest that EGFR signaling activates downstream PI3K/Akt to increase MMP9 expression in glioblastoma, while phosphorylation of Akt is a control point by miRNA-181c.
Therefore, while under normoxic conditions, EGF stimulates the activation of both the PI3K and the MAPK pathways and the induction of VEGF, in glioblastoma cells, hypoxic conditions lead to the suppression of the PI3K/RhoA/C pathway and an exclusive switch to the MAPK pathway.
The activation of PI3K/Akt1 signaling pathway is involved in the proliferation of glioblastoma; however, the underlying mechanism of Akt1 activation during the development of glioblastoma remains largely unclear.
Here we show that overexpression of NEU3 in glioblastoma U87MG cells activates PI3K/Akt signaling pathway resulting in an increased radioresistance capacity and in an improved efficiency of double strand DNA-repair mechanisms after irradiation.
Further, photofrin based PDT followed by miR-99a transfection dramatically increased miR-99a expression and also increased apoptosis in glioblastoma cell cultures and drastically reduced tumor growth in athymic nude mice, due to down regulation of fibroblast growth factor receptor 3 (FGFR3) and PI3K/Akt signaling mechanisms leading to inhibition of cell proliferation and induction of molecular mechanisms of apoptosis.
We have examined the relative roles of the two major phospholipid products of PI3K activity, phosphatidylinositol 3,4-biphosphate [PtdIns(3,4)P2] and phosphatidylinositol 3,4,5-triphosphate [PtdIns(3,4,5)P3], in the regulation of PKB activity in glioblastoma cells containing high levels of both of these lipids due to defective PTEN expression.
This study was a multicenter, open-label, multi-arm, phase II trial in patients with PI3K pathway-activated glioblastoma at first or second recurrence.
Rapamycin has anticancer activity in PTEN-deficient glioblastoma and warrants further clinical study alone or in combination with PI3K pathway inhibitors.
In conclusion, the current study demonstrated for the first time that inhibition of RWDD3 expression inhibited glioblastoma progression, at least partly, via suppressing the PI3K/AKT signaling activity, and thus RWDD3 may be a novel potential therapeutic target for glioblastoma.
PIK3R3, the gene that encodes the PI3K regulatory subunit p55γ, is over-expressed in glioblastoma and ovarian cancers, but its expression in gastric cancer (GC) is not known.
The PI3K pathway is commonly activated in glioblastoma and promotes tumor cell survival, suggesting that its inhibition would make cells more sensitive to cytotoxic agents.
In conclusion, DPT effectively inhibited the expression of PI3K and downregulated PI3K/Akt‑mediated signaling pathways to prevent glioblastoma progression.
Combination of all-trans retinoic acid and interferon-gamma suppressed PI3K/Akt survival pathway in glioblastoma T98G cells whereas NF-kappaB survival signaling in glioblastoma U87MG cells for induction of apoptosis.
Using single-cell tracking and wound healing migration tests, colony-forming assay, Western blotting, flow cytometry and electrorotation we examined the effects of MK-2206 and PI-103 and/or irradiation on the migration, radiation sensitivity, expression of several marker proteins, DNA damage, cell cycle progression and the plasma membrane properties in two glioblastoma (DK-MG and SNB19) cell lines, previously shown to differ markedly in their migratory behavior and response to PI3K/mTOR inhibition.
Our results show that our in vitro NMR-detected changes in lactate and choline metabolites may have potential as non-invasive biomarkers for monitoring response to combination of PI3K/mTOR inhibitors with TMZ during clinical trials in children with glioblastoma, subject to further in vivo validation.
Inhibition of PI3K in U87MG glioblastoma cells, which have activated PI3K/Akt activity secondary to phosphatase and tensin homologue deleted on chromosome 10 (PTEN) mutation, with LY294002 blunted the induction of HIF-1alpha protein and its targets vascular endothelial growth factor and glut1 mRNA in response to hypoxia.