Search results for "ERK pathway"

Ability of nanocrystalline hydroxyapatite paste to promote human periodontal ligament cell proliferation.

2008

Recent studies indicate that nanocrystalline hydroxyapatite (nano-HA) paste represents a promising class of bone graft substitute. However, the underlying molecular mechanisms of nano-HA function have not yet been determined. This study was conducted to investigate the proliferation of human periodontal ligament (PDL) cells cultured in the presence of nano-HA paste and to characterize associated changes in intracellular signaling pathways. Cultured PDL cells were stimulated with nano-HA paste and enamel matrix derivative (EMD) in a soluble form. Proliferation of PDL cells was determined by incorporation of bromodeoxyuridine (BrdU) in the DNA of proliferating cells. In order to understand th…

Mutations and Deregulation of Ras/Raf/MEK/ERK and PI3K/PTEN/Akt/mTOR Cascades Which Alter Therapy Response.

2012

The Ras/Raf/MEK/ERK and PI3K/PTEN/Akt/mTOR cascades are often activated by genetic alterations in upstream signaling molecules such as receptor tyrosine kinases (RTK). Certain components of these pathways, RAS, NF1, BRAF, MEK1, DUSP5, PP2A, PIK3CA, PIK3R1, PIK3R4, PIK3R5, IRS4, AKT, NFKB1, MTOR, PTEN, TSC1, and TSC2 may also be activated/inactivated by mutations or epigenetic silencing. Upstream mutations in one signaling pathway or even in downstream components of the same pathway can alter the sensitivity of the cells to certain small molecule inhibitors. These pathways have profound effects on proliferative, apoptotic and differentiation pathways. Dysregulation of components of these cas…

Characteristic ERK Signaling Dynamics Distinguishes Necroptosis from Apoptosis

2021

ERK involvement in cell death remains unclear, although many studies have demonstrated the importance of ERK dynamics in determining cellular responses. To untangle ERK’s contribution in two cell death programs, we investigated ERK signaling dynamics during hFasL-induced apoptosis and TNF-induced necroptosis in L929sAhFas cells. We observed that ERK inhibition sensitizes cells to apoptosis while delaying necroptosis. By monitoring ERK activity by live-cell imaging using an improved ERK biosensor (EKAR4.0), we reported differential ERK signaling dynamics between cell survival, apoptosis, and necroptosis. We also decrypted a temporally shifted amplitude- and frequency-modulated (AM/FM) ERK ac…

The role of death effector domain (DED)-containing proteins in acute oxidative cell injury in hepatocytes

2012

Abstract Apoptosis is a mechanism that regulates hepatic tissue homeostasis and contributes to both acute and chronic injury in liver disease. The apoptotic signaling cascade involves activation of the death-inducing signaling complex (DISC) and subsequent recruitment of proteins containing death effector domains (DED), which regulate downstream effector molecules. Prominent among these are the Fas-associated death domain (FADD) and the cellular caspase 8-like inhibitory protein (cFLIP), and alterations in these proteins can lead to severe disruption of physiological processes, including acute liver failure or hepatocellular carcinoma. Their role in cell signaling events independent of the …

Emerging Raf inhibitors

2009

The Raf/MAPK kinase/extracellular-signal-regulated kinase pathway is often activated by genetic alterations in upstream signaling molecules. An integral component of this pathway, BRAF, is also activated by mutation, especially in melanoma and thyroid cancers. The Raf/MAPK kinase/extracellular-signal-regulated kinase pathway has profound effects on proliferative, apoptotic and differentiation pathways as well as the sensitivity and resistance to chemotherapeutic drugs.This review discusses targeting of Raf which could control abnormal proliferation in cancer and other proliferative diseases. The important roles that genetics plays in the response of patients to Raf inhibitors is also evalua…

B-Raf-mediated signaling pathway regulates T cell development

2008

The activities of the Raf kinase family proteins control extracellular signal-regulated kinase (ERK) activation in many aspects of cellular responses. However, the relative contributions of individual isozymes to cellular functions including T cell responses are still unclear. In addition to Raf-1, another Raf family kinase, B-Raf, is expressed in murine thymocytes and peripheral T cells, and its activation was induced by TCR stimulation. Here, we investigated the function of B-Raf in development of T cells by generating chimeric mice in which a T cell-compromised host was reconstituted with fetal liver-derived cells from embryonic lethal B-Raf-deficient mice. Although B-Raf was dispensable…

BRAF mutations in non-small cell lung cancer : has finally Janus opened the door?

2016

Abstract: B-Raf mutations occur in about 1-2% of non-small cell lung cancers (NSCLC). These mutations generate a permanent activation of the mitogen activated protein kinase (MAPK) pathway, which promotes tumor growth and proliferation. In the present review, we discuss B-Raf mutation epidemiology, diagnostic methods to detect B-Raf mutations, the role of B-Raf as a driver mutation and a potential therapeutic target in NSCLC. The results of clinical trials involving B-Raf or MAPK pathway inhibitors for the treatment of NSCLC are also discussed. Clinical trials evaluating B-Raf inhibitors in BRAF mutated NSCLC patients have shown promising results, and larger prospective studies are warrante…

Highlight on transient activation of red/ox-dependent survival signals involving MEK/ERK and PI3/Akt signaling pathways in 27-hydroxycholesterol trea…

2014

Heat shock proteins in fibrosis and wound healing: Good or evil?

2014

Heat shock proteins (HSPs) are key regulators of cell homeostasis, and their cytoprotective role has been largely investigated in the last few decades. However, an increasing amount of evidence highlights their deleterious effects on several human pathologies, including cancer, in which they promote tumor cell survival, proliferation and drug resistance. Therefore, HSPs have recently been suggested as therapeutic targets for improving human disease outcomes. Fibrotic diseases and cancer share several properties; both pathologies are characterized by genetic alterations, uncontrolled cell proliferation, altered cell interactions and communication and tissue invasion. The discovery of new HSP…

2-(6-Methoxy-7H-purin-7-yl)-1-phenylethanone monohydrate

2007

The crystal structure of the title compound, C14H12N4O2·H2O, was determined in the course of our studies of the synthesis and optimization of 7-aryl-7H-purines as inhibitors of the vascular endothelial growth factor receptor (VEGF-R), c-Jun NH2-terminal protein kinase 3 (JNK3) and the p38α mitogen-activated protein kinase (MAPK). In the title compound, two mol­ecules are associated with each other through O—H⋯N hydrogen bonds to different N atoms in the purine ring system. The compound was prepared via a regioselective synthesis using the meth­yl(aqua)cobaloxime complex, CH3Co(DH)2OH2, as a temporary auxiliary. The X-ray crystallographic results confirmed the regioselective N-7 alkyl­ation …