Activating mutations of the NRAS (neuroblastoma rat sarcoma viral oncogene) protein kinase, present in many cancers, induce a constitutive activation of both the RAS-RAF-MEK-ERK mitogen-activated protein kinase (MAPK) signal transduction pathway and the PI(3)K-AKT-mTOR, pathway.
Additionally, Ras family members (Hras1, Kras2 and Nras) and the downstream effectors Pik3ca and Braf, were sequenced from twenty-five neuroblastomas arising in neuroblastoma-prone transgenic mice.
Autophagy markers were also measured in cypermethrin-treated neuroblastoma cells in the presence of 3-methyl adenine, a phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K) class III inhibitor; vinblastine, an autophagosome elongation inhibitor; bafilomycin A1, an autophagolysosome and lysosome fusion/abnormal acidification inhibitor or torin 1, a mechanistic target of rapamycin inhibitor.
Both MAPK and PI3K pathways were involved in BDNF protection of NB cells from paclitaxel-induced cell death, while PI3K predominantly mediated BDNF protection of NB cells from etoposide or cisplatin-induced cell death.
Consistent with these observations, PI3K inhibition in MYCN-amplified human neuroblastoma cell lines resulted in decreased levels of Mycn protein without affecting levels of MYCN mRNA and caused decreased proliferation and increased apoptosis.
Evaluation of the expression of these PI3K genes can predict aggressive disease, and indicates stage-dependent involvement of PI3K-pathway members in neuroblastoma.
Here we demonstrate that PI3K/Akt pathway is crucial for the upregulation of P2X7R expression in serum-deprived neuroblastoma cells, circumstance that facilitates cell proliferation in the absence of trophic support.
Here, we show that p37δ, a kinase-dead isoform of the PI3K catalytic subunit p110δ, is over-expressed in neuroblastoma tumors, and that it correlates with the activation of both PI3K/Akt- and RAS-signaling pathways.
However, NVP-BEZ235, a potent dual PI3K and mTOR inhibitor have not shown beneficial effects on neuroblastoma especially in terms of apoptosis induction as a single agent.
In summary, we found NLGN3 promoted neuroblastoma cell proliferation and growth through activating PI3K/AKT pathway and providing a new target for neuroblastoma therapy.
In this study we investigated the phosphorylation status of key proteins in the PI3K/AKT/mTOR pathway and the effects of the mTOR inhibitors rapamycin and CCI-779 on neuroblastoma tumorigenesis.
Moreover, inhibitors of PI3K/mTOR and GLI signaling reduced neuroblastoma cell growth, but no additional growth inhibitory effects were detected when the two classes of drugs were combined.
Our data also suggest that the phosphoinositide 3-kinase (PI3K) inhibitors may provide new opportunities for the treatment of the <i>MYCN</i>-amplified neuroblastoma subtype.
Our previous studies have demonstrated that PI3K/AKT signaling is critical for the oncogenic transformations induced by gastrin-releasing peptide (GRP) and its receptor, GRP-R, in neuroblastoma.
Palmitic acid stimulates energy metabolism and inhibits insulin/PI3K/AKT signaling in differentiated human neuroblastoma cells: The role of mTOR activation and mitochondrial ROS production.
Pharmacological inhibition of PI3K greatly reduced the ability of PDGF-BB to block gp120 IIIB-mediated apoptosis and cell death in human neuroblastoma cells.