Background: The development of radiosensitizers that modulate activated signaling pathways has enhanced effective cancer treatment via radiation therapy. phosphoinositide 3-kinases (PI3K)/protein kinase B (AKT) pathway induces progression and radioresistance. Therefore, we investigated if HS-173, a novel PI3K inhibitor, could increase the radiosensitivity in breast cells. Materials Methods: Bre...

Objective: To investigate the role of KIF3C gene in promoting malignant phenotype lung cancer cells and regulating PI3K/AKT signaling pathway. Methods: CCK-8 transwell assays were used to detect changes cell proliferation migration ability after being transfected with siKIF3C, as well protein expression levels PI3K, p-PI3K, AKT, p-AKT following downregulation by Western blot. Results: The assay...

PI3K (phosphoinositide 3-kinase) is a key regulator of cell growth, metabolism and survival. The frequent activation of the PI3K pathway in cancer has stimulated widespread interest in identifying potent and selective inhibitors of PI3K isoforms. The present paper highlights recent progress in identifying such molecules and the challenges that remain for efforts to pharmacologically target the ...

Prostaglandin E(2) (PGE(2)) plays an important role in the regulation of duodenal bicarbonate (HCO(3)(-)) secretion, but its signaling pathway(s) are not fully understood. In the present study, we investigated the signaling pathways involved in PGE(2)-mediated duodenal HCO(3)(-) secretion. Murine duodenal mucosal HCO(3)(-) secretion was examined in vitro in Ussing chambers by pH-stat titration ...

PURPOSE To determine the mechanisms of action of phosphatidylinositol 3-kinase (PI3K) in lens cell differentiation and survival. METHODS Primary quail lens cell cultures were treated at different stages of differentiation with the PI3K inhibitor LY294002, and expression of survival proteins and differentiation markers were determined by immunoblot analysis. The connection between PI3K regulat...

Phosphoinositide 3-kinase (PI3K)gamma and Dictyostelium PI3K are activated via G protein-coupled receptors through binding to the Gbetagamma subunit and Ras. However, the mechanistic role(s) of Gbetagamma and Ras in PI3K activation remains elusive. Furthermore, the dynamics and function of PI3K activation in the absence of extracellular stimuli have not been fully investigated. We report that g...

Activation of the enzyme PLC (phospholipase C) leads to the formation of second messengers Ins(1,4,5)P(3) and diacylglycerol. RTKs (receptor tyrosine kinases) activate this reaction through PLCgamma isoenzymes. It has been shown that PI3K (phosphoinositide 3-kinase) may regulate PLCgamma activity through the interaction of PI3K product PtdIns(3,4,5)P(3) and the PLCgamma PH domain (pleckstrin ho...

Bile acids are known to induce Ca(2+) signals in pancreatic acinar cells. We have recently shown that phosphatidylinositol 3-kinase (PI3K) regulates changes in free cytosolic Ca(2+) concentration ([Ca(2+)](i)) elicited by CCK by inhibiting sarco(endo)plasmic reticulum Ca(2+)-ATPase (SERCA). The present study sought to determine whether PI3K regulates bile acid-induced [Ca(2+)](i) responses. In ...

The phosphatidylinositol 3-kinase (PI3K) pathway plays an important role in many biological processes, including cell cycle progression, cell growth, survival, actin rearrangement and migration, and intracellular vesicular transport. However, the involvement of the PI3K pathway in the regulation of mitotic cell death remains unclear. In this study, we treated HeLa cells with the PI3K inhibitors...

We investigated whether phosphatidylinositol 3-kinase (PI3K) is phosphorylated and whether its specific activity is increased by insulin stimulation in vivo using Fao cells and antibodies raised against the 85 kDa subunit of PI3K, insulin-receptor substrate-1 (IRS-1), and phosphotyrosine (pTyr). PI3K activity was detected in the immunoprecipitate produced with anti-PI3K at a basal state. The ac...