The phosphatidylinositol 3-kinase (PI3K) signaling pathway has inherent oncogenic potential. It is up-regulated in diverse human cancers by either a gain of function in PI3K itself or in its downstream target Akt or by a loss of function in the negative regulator PTEN. However, the complete consequences of this up-regulation are not known. Here we show that insulin and epidermal growth factor o...

We have investigated the mechanisms of leading edge formation in chemotaxing Dictyostelium cells. We demonstrate that while phosphatidylinositol 3-kinase (PI3K) transiently translocates to the plasma membrane in response to chemoattractant stimulation and to the leading edge in chemotaxing cells, PTEN, a negative regulator of PI3K pathways, exhibits a reciprocal pattern of localization. By unif...

BACKGROUND Legionella pneumophila, is an intracellular pathogen that causes Legionnaires' disease in humans, a potentially lethal pneumonia. L. pneumophila has the ability to enter and replicate in the host and is essential for pathogenesis. METHODOLOGY/PRINCIPAL FINDINGS Phagocytosis was measured by cell invasion assays. Construction of PI3K mutant by PCR cloning and expression of dominant n...

Recent work has demonstrated that the PI3K (phosphoinositide 3-kinase) signalling pathway is important for efficient influenza A virus replication. Activation of PI3K in virus-infected cells is mediated by the viral NS1 protein, which binds directly to the p85beta regulatory subunit of PI3K and causes the PI3K-dependent phosphorylation of Akt (protein kinase B). Given that recombinant influenza...

Signaling from collagen and G protein– coupled receptors leads to platelet adhesion and subsequent thrombus formation. Paracrine agonists such as ADP, thromboxane, and Gas6 are required for platelet aggregate formation. We hypothesized that thrombi are intrinsically unstable structures and that their stabilization requires persistent paracrine activity and continuous signaling, maintaining inte...

Background and aims: Chlorpyrifos (CPF) is an insecticide that widely used in the world. The purpose of this research was to investigate effect 4-week aerobic exercise eugenol supplementation on phosphatidylinositol-3-kinases/protein kinase/mammalian target rapamycin (Pi3K/AKT/mTOR) pathway skeletal muscle male rats poisoned with CPF. Methods: Overall, 12-week-old female were experimental resea...

The dual specificity protein/lipid kinase, phosphoinositide 3-kinase (PI3K), promotes growth factor-mediated cell survival and is frequently deregulated in cancer. However, in contrast to canonical lipid-kinase functions, the role of PI3K protein kinase activity in regulating cell survival is unknown. We have employed a novel approach to purify and pharmacologically profile protein kinases from...

PURPOSE Locoregional recurrence is the dominant form of treatment failure in head and neck (H&N) cancer. The epidermal growth factor receptor (EGFR) is frequently amplified in this disease (<or=80%) and can lead to activation of phosphatidylinositol-3-kinase (PI3K), both directly and indirectly through Ras. We have shown previously that radioresistance could be conferred via the Ras-PI3K pathwa...

background: the phosphatidylinositol 3-kinase/akt signaling pathway is recognized as a key driver of cancer cell survival and proliferation, and is often contingent upon an impairment of expression/function of the pten tumor suppressor, a negative regulator of this pathway. in addition, the cytoskeletal signaling protein tensin 2 has also been implicated as a negative regulator of this pathway....