Phosphatidylinositol-3 kinase (PI3K) is one of the most important regulatory proteins that is involved in different signaling pathways and controlling of key functions of the cell. The double-enzymatic activity of PI3K (lipid kinase and protein kinase) as well as the ability of this enzyme to activate a number of signal proteins including some oncoproteins determines its fundamental significanc...

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...

UNLABELLED Recent proteomic data have uncovered an interdependence of PI3K and STAT3. In PI3K-tranformed murine cells, STAT3 is phosphorylated on Y705 and activated in a PI3K-dependent manner. Dominant negative STAT3 interferes with PI3K-induced oncogenic transformation. Phosphorylation of STAT3 in PI3K-transformed murine cells is mediated by the TEC kinase BMX. Observations on glioblastoma ste...

The phosphoinositide 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) pathway is frequently activated in human cancer and plays a crucial role in glioblastoma biology. We were interested in gaining further insight into the potential of targeting PI3K isoforms as a novel anti-tumor approach in glioblastoma. Consistent expression of the PI3K catalytic isoform PI3K p110α was detected in a ...

BACKGROUND Phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway, activated during influenza A virus infection, can promote viral replication via multiple mechanisms. Direct binding of NS1 protein to p85β subunit of PI3K is required for activation of PI3K/Akt signaling. Binding and subsequent activation of PI3K is believed to be a conserved character of influenza A virus NS1 protein. Seque...

Activation of the PI3K-Akt-FoxO pathway induces cell growth, whereas its inhibition reduces cell survival and, in muscle, causes atrophy. Here, we report a novel mechanism that suppresses PI3K-Akt-FoxO signaling. Although skeletal muscle lacks desmosomes, it contains multiple desmosomal components, including plakoglobin. In normal muscle plakoglobin binds the insulin receptor and PI3K subunit p...

BACKGROUND: Growth factor, cytokine and chemokine-induced activation of PI3K enzymes constitutes the start of a complex signalling cascade, which ultimately mediates cellular activities such as proliferation, differentiation, chemotaxis, survival, trafficking, and glucose homeostasis. The PI3K enzyme family is divided into 3 classes; class I (subdivided into IA and IB), class II (PI3K-C2alpha, ...

BACKGROUND We previously synthesized a novel s-triazine derivative, ZSTK474 [2-(2-difluoromethylbenzimidazol-1-yl)-4,6-dimorpholino-1,3,5-triazine], that strongly inhibited the growth of tumor cells. We identified its molecular target, investigated its effects on cellular signaling pathways, and examined its antitumor efficacy and toxicity in vivo. METHODS We used COMPARE analysis of chemosen...

the lung cancer is one of the most dangerous cancers and is also the leading cause of cancer death worldwide, accounting for about 1.3 million deaths annually. however in clinical practice, lung cancer therapies commonly do with chemotherapy, although it is hard because the lung cancer may progress to metastasis stage. the metastasis of lung cancer is highly dependent of expression of matrix me...

We determined whether active PI3K signaling together with nuclear accumulation of β-Catenin is necessary to fully activate canonical WNT signaling and examined the association of both signaling pathways with colon cancer progression. Using reporter gene assays we examined the activation of β-Catenin mediated transcription upon PI3K inhibition with or without β-Catenin nuclear accumulation. Ecto...