Search results for "pi3k"

GSK-3 as potential target for therapeutic intervention in cancer

2014

// James A. McCubrey 1 , Linda S. Steelman 1 , Fred E. Bertrand 2 , Nicole M. Davis 1 , Melissa Sokolosky 1 , Steve L. Abrams 1 , Giuseppe Montalto 3 , Antonino B. D’Assoro 4 , Massimo Libra 5 , Ferdinando Nicoletti 5 , Roberta Maestro 6 , Jorg Basecke 7,8 , Dariusz Rakus 9 , Agnieszka Gizak 9 Zoya Demidenko 10 , Lucio Cocco 11 , Alberto M. Martelli 11 and Melchiorre Cervello 12 1 Department of Microbiology and Immunology, Brody School of Medicine at East Carolina University Greenville, NC, USA 2 Department of Oncology, Brody School of Medicine at East Carolina University Greenville, NC, USA 3 Biomedical Department of Internal Medicine and Specialties, University of Palermo, Palermo, Italy …

Repression of Human Papillomavirus Oncogene Expression under Hypoxia Is Mediated by PI3K/mTORC2/AKT Signaling

2019

Oncogenic HPV types are major human carcinogens. Under hypoxia, HPV-positive cancer cells can repress the viral E6/E7 oncogenes and induce a reversible growth arrest. This response could contribute to therapy resistance, immune evasion, and tumor recurrence upon reoxygenation. Here, we uncover evidence that HPV oncogene repression is mediated by hypoxia-induced activation of canonical PI3K/mTORC2/AKT signaling. AKT-dependent downregulation of E6/E7 is only observed under hypoxia and occurs, at least in part, at the transcriptional level. Quantitative proteome analyses identify additional factors as candidates to be involved in AKT-dependent E6/E7 repression and/or hypoxic PI3K/mTORC2/AKT ac…

De novo CCND2 mutations leading to stabilization of cyclin D2 cause megalencephaly-polymicrogyria-polydactyly-hydrocephalus syndrome

2014

Activating mutations in genes encoding phosphatidylinositol 3-kinase (PI3K)-AKT pathway components cause megalencephaly-polymicrogyria-polydactyly-hydrocephalus syndrome (MPPH, OMIM 603387)(1-3). Here we report that individuals with MPPH lacking upstream PI3K-AKT pathway mutations carry de novo mutations in CCND2 (encoding cyclin D2) that are clustered around a residue that can be phosphorylated by glycogen synthase kinase 313 (GSK-3 beta)(4). Mutant CCND2 was resistant to proteasomal degradation in vitro compared to wild-type CCND2. The PI3K-AKT pathway modulates GSK-3 beta activity(4), and cells from individuals with PIK3CA, PIK3R2 or AKT3 mutations showed similar CCND2 accumulation. CCND…

Effects of combined hormone replacement therapy or its effective agents on the IGF-1 pathway in skeletal muscle.

2010

Objectives To investigate the effects of combined hormone replacement therapy (HRT) and its effective agents on the IGF-1 signaling pathway. Design and methods To examine the effects of HRT on skeletal muscle in vivo, we utilized pre- and post-intervention samples from a randomized double blinded trial with 50–57-year-old women. The intervention included the year-long use of either HRT preparation (2 mg 17β-estradiol, E2; 1 mg norethisterone acetate, NETA, n = 10) or placebo (CO, n = 9). Microarray technology and quantitative PCR (qPCR) were used to study the expression of insulin-like growth factor I (IGF-1) and its splice variants as well as IGF-1 receptor, Akt1, mTOR, FOXO1, FOXO3, atrog…

Acetic Acid Mediated for One-Pot Synthesis of Novel Pyrazolyl s-Triazine Derivatives for the Targeted Therapy of Triple-Negative Breast Tumor Cells (…

2022

Here, we described the synthesis of novel pyrazole-s-triazine derivatives via an easy one-pot procedure for the reaction of β-dicarbonyl compounds (ethylacetoacetate, 5,5-dimethyl-1,3-cyclohexadione or 1,3-cyclohexadionone) with N,N-dimethylformamide dimethylacetal, followed by addition of 2-hydrazinyl-4,6-disubstituted-s-triazine either in ethanol-acetic acid or neat acetic acid to afford a novel pyrazole and pyrazole-fused cycloalkanone systems. The synthetic protocol proved to be efficient, with a shorter reaction time and high chemical yield with broad substrates. The new pyrazolyl-s-triazine derivatives were tested against the following cell lines: MCF-7 (breast cancer); MDA-MB-231 (tr…

Neural Stem Cells in the Adult Brain: From Benchside to Clinic

2012

Increasing evidence indicates that neural stem cells (NSCs) play an important role in sustaining cellular homeostasis and brain tissue restoration. The study of all mechanisms that control and modulate the function of NSC is a crucial step for the design of therapies against chronic neurodegenerative processes. In this special issue of the journal, we had the pleasure to edit the topic entitled “Neural Stem Cells in the Adult Brain: From Benchside to Clinic.” This special compilation of paper was aimed to provide a global forum for publications of original peer-reviewed manuscripts that reported original research findings in the field of adult neural stem cell, including short communication…

Mutant HRAS as novel target for MEK and mTOR inhibitors.

2015

HRAS is a frequently mutated oncogene in cancer. However, mutant HRAS as drug target has not been investigated so far. Here, we show that mutant HRAS hyperactivates the RAS and the mTOR pathway in various cancer cell lines including lung, bladder and esophageal cancer. HRAS mutation sensitized toward growth inhibition by the MEK inhibitors AZD6244, MEK162 and PD0325901. Further, we found that MEK inhibitors induce apoptosis in mutant HRAS cell lines but not in cell lines lacking RAS mutations. In addition, knockdown of HRAS by siRNA blocked cell growth in mutant HRAS cell lines. Inhibition of the PI3K pathway alone or in combination with MEK inhibitors did not alter signaling nor had an imp…

Author response: PTEN negatively regulates the cell lineage progression from NG2+ glial progenitor to oligodendrocyte via mTOR-independent signaling

2018

Amphiregulin activates human hepatic stellate cells and is upregulated in non alcoholic steatohepatitis

2015

AbstractAmphiregulin (AR) involvement in liver fibrogenesis and hepatic stellate cells (HSC) regulation is under study. Non-alcoholic fatty liver disease (NAFLD) and its more severe form non-alcoholic steatohepatitis (NASH) may progress to cirrhosis and hepatocellular cancer (HCC). Our aim was to investigate ex vivo the effect of AR on human primary HSC (hHSC) and verify in vivo the relevance of AR in NAFLD fibrogenesis. hHSC isolated from healthy liver segments were analyzed for expression of AR and its activator, TNF-α converting enzyme (TACE). AR induction of hHSC proliferation and matrix production was estimated in the presence of antagonists. AR involvement in fibrogenesis was also ass…

Acute estradiol protects CA1 neurons from ischemia-induced apoptotic cell death via the PI3K/Akt pathway

2010

Global ischemia arising during cardiac arrest or cardiac surgery causes highly selective, delayed death of hippocampal CA1 neurons. Exogenous estradiol ameliorates global ischemia-induced neuronal death and cognitive impairment in male and female rodents. However, the molecular mechanisms by which a single acute injection of estradiol administered after the ischemic event intervenes in global ischemia-induced apoptotic cell death are unclear. Here we show that acute estradiol acts via the phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) signaling cascade to protect CA1 neurons in ovariectomized female rats. We demonstrate that global ischemia promotes early activation of glycogen syn…