UNLABELLED Assessing the extent of PI3K pathway activity in cancer is vital to predicting sensitivity to PI3K-targeting drugs, but the best biomarker of PI3K pathway activity in archival tumor specimens is unclear. Here, PI3K pathway activation was assessed, in clinical tissue from 1,021 men with prostate cancers, using multiple pathway nodes that include PTEN, phosphorylated AKT (pAKT), phosph...

background: acute lymphoblastic leukemia (all), the most common childhood cancer with a peak incidence in children from 2-5 years old, might be associated with poor prognosis and resistance to therapy in specific cytogenetic backgrounds. foxo3a, a member of the forkhead class 'o' (foxo) transcription factors, is a main downstream target of pi3k/akt pathway which regulates different variety of b...

PI3K involvement has been implicated in the TLR signal pathway. However, the precise roles of the different classes of PI3K in the pathway remain elusive. In this study, we have explored the functions of class I and class III PI3K in the TLR signal pathway using specific kinase mutants and PI3K lipid products. Our results reveal that class III PI3K specifically regulates CpG oligodeoxynucleotid...

Bruton's tyrosine kinase (Btk) acts downstream of phosphoinositide 3-kinase (PI3K) in a pathway required for B cell receptor (BCR)-dependent proliferation. We used DNA microarrays to determine what fraction of genes this pathway influences and to investigate whether PI3K and Btk mediate distinct gene regulation events. As complete loss-of-function mutations in PI3K and Btk alter B cell subpopul...

Phosphatidylinositide 3-kinase (PI3K) is a key enzyme implicated in intracellular signaling of diverse cellular responses including receptor-mediated responses and neutrophil activation. Several PI3K subunits have been cloned and shown to be localized to plasma membrane receptors, the cytosol, or intracellular vesicles or caveolae. We report the localization of PI3K to a distinct intracellular ...

The phosphatidylinositol 3-kinase (PI3K) pathway is commonly deregulated in cancer. In recent years, the results of the first phase I clinical trials with PI3K inhibitors have become available. In comparison to other targeted agents such v-raf murine sarcoma viral oncogene homolog B1 (BRAF) inhibitors in melanoma or crizotinib in anaplastic lymphoma receptor tyrosine kinase (ALK) translocated t...

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: Non-small cell lung cancer (NSCLC), caused by abnormal gene drive, may have primary drug resistance after treatment with tyrosine kinase inhibitors (EGFR-TKIs). Therefore, we explore whether the drug-resistant NSCLC treated EGFR-TKI is related to miR-21/Sonic Hedgehog (SHH)/PI3K/AKT pathway. Methods: The patients from our hospital who meet AJCC TNM staging (7th edition) stage IIIB a...

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...

Phosphatidylinositol 3-kinase (PI3K) promotes cell survival and communication by activating its downstream effector Akt kinase. Here we show that PS1, a protein involved in familial Alzheimer's disease (FAD), promotes cell survival by activating the PI3K/Akt cell survival signaling. This function of PS1 is unaffected by gamma-secretase inhibitors. Pharmacological and genetic evidence indicates ...