scholarly journals Rapid and transient induction of cyclo-oxygenase 2 by epidermal growth factor in human amnion-derived WISH cells

1997 ◽  
Vol 321 (3) ◽  
pp. 677-681 ◽  
Author(s):  
Douglas J. PERKINS ◽  
Douglas A. KNISS
Keyword(s):  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Protein Expression ◽  
De Novo ◽  
Tnf Α ◽  
Mrna And Protein Expression ◽  
Epidermal Growth ◽  
Cox 2 ◽  
Dose Dependent ◽  
Cox 1

The central enzyme in the prostaglandin (PG) biosynthetic cascade is PGH2 synthase or cyclo-oxygenase (COX). At present, two distinct isoforms of PGH2 synthase/COX have been identified: COX-1 and COX-2. In many systems, COX-1 is a constitutively expressed isoform that is responsible for normal physiological production of PGs, whereas COX-2 is an inducible isoform that responds to cytokines, endotoxin and growth factors by producing high levels of PGs. The regulation of COX-2 mRNA and protein, and the subsequent production of PGE2, were therefore examined in amnion-derived WISH cells stimulated with epidermal growth factor (EGF). Treatment of WISH cells with EGF (0.01Ő100 ng/ml) elicited dose-dependent synthesis of COX-2 mRNA and protein de novo. In addition, stimulation of WISH cells with EGF (10 ng/ml) induced steady-state levels of COX-2 mRNA and protein that appeared within 30 min and then declined rapidly to near baseline levels within 2Ő4 h. In contrast, COX-1 protein was unchanged in response to treatment with EGF. PGE2 production was also rapid and transient. Preincubation of cells with the novel COX-2 enzymic inhibitor NS-398 (10-5Ő10-10 M) completely prevented PGE2 formation in a dose-dependent manner. Preincubation of cells in dexamethasone (Dex; 0.1 ƁM), however, resulted in only a 31% decrease in PGE2 formation in response to EGF (10 ng/ml) while completely attenuating PGE2 biosynthesis in tumour necrosis factor α (TNF-α)-stimulated cells. In addition, Dex (0.1 ƁM) was only partly effective at preventing EGF-induced COX-2 mRNA and protein expression de novo, whereas Dex completely inhibited TNF-α-promoted COX-2 mRNA and protein expression. Thus the results presented here demonstrate that EGF induces the rapid but transient expression of COX-2 mRNA and protein and the subsequent production of PGE2 in WISH cells.

947: Chemopreventive Effects of COX-2 Inhibitor and Epidermal Growth Factor (EGF)-Receptor Kinase Inhibitor on Rat Urinary Bladder Tumorigenesis

2004 ◽  
Vol 171 (4S) ◽  
pp. 251-251
Author(s):  
Kazunori Hattori ◽  
Katsuyuki Iida ◽  
Akira Johraku ◽  
Sadamu Tsukamoto ◽  
Taeko Asano ◽  
...  
Keyword(s):  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Urinary Bladder ◽  
Egf Receptor ◽  
Kinase Inhibitor ◽  
Receptor Kinase ◽  
Rat Urinary Bladder ◽  
Epidermal Growth ◽  
Cox 2

Epidermal growth factor receptor transactivation is required for proteinase-activated receptor-2-induced COX-2 expression in intestinal epithelial cells

2012 ◽  
Vol 303 (1) ◽  
pp. G111-G119 ◽  
Author(s):  
Christina L. Hirota ◽  
France Moreau ◽  
Vadim Iablokov ◽  
Michael Dicay ◽  
Bernard Renaux ◽  
...  
Keyword(s):  
Colon Cancer ◽  
Epidermal Growth Factor Receptor ◽  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Intestinal Epithelial Cells ◽  
Growth Factor Receptor ◽  
Intestinal Epithelial ◽  
Kinase Signaling ◽  
Epidermal Growth ◽  
Cox 2

Proteinase-activated receptor (PAR)2, a G protein-coupled receptor activated by serine proteinases, has been implicated in both intestinal inflammation and epithelial proliferation. Cyclooxygenase (COX)-2 is overexpressed in the gut during inflammation as well as in colon cancer. We hypothesized that PAR2 drives COX-2 expression in intestinal epithelial cells. Treatment of Caco-2 colon cancer cells with the PAR2-activating peptide 2-furoyl-LIGRLO-NH2 (2fLI), but not by its reverse-sequence PAR2-inactive peptide, for 3 h led to an increase in intracellular COX-2 protein expression accompanied by a COX-2-dependent increase in prostaglandin E2 production. 2fLI treatment for 30 min significantly increased metalloproteinase activity in the culture supernatant. Increased epidermal growth factor receptor (EGFR) phosphorylation was observed in cell lysates following 40 min of treatment with 2fLI. The broad-spectrum metalloproteinase inhibitor marimastat inhibited both COX-2 expression and EGFR phosphorylation. The EGFR tyrosine kinase inhibitor PD153035 also abolished 2fLI-induced COX-2 expression. Although PAR2 activation increased ERK MAPK phosphorylation, neither ERK pathway inhibitors nor a p38 MAPK inhibitor affected 2fLI-induced COX-2 expression. However, inhibition of either Src tyrosine kinase signaling by PP2, Rho kinase signaling by Y27632, or phosphatidylinositol 3 (PI3) kinase signaling by LY294002 prevented 2fLI-induced COX-2 expression. Trypsin increased COX-2 expression through PAR2 in Caco-2 cells and in an EGFR-dependent manner in the noncancerous intestinal epithelial cell-6 cell line. In conclusion, PAR2 activation drives COX-2 expression in Caco-2 cells via metalloproteinase-dependent EGFR transactivation and activation of Src, Rho, and PI3 kinase signaling. Our findings provide a mechanism whereby PAR2 can participate in the progression from chronic inflammation to cancer in the intestine.

scholarly journals The Jun Kinase 2 Isoform Is Preferentially Required for Epidermal Growth Factor-Induced Transformation of Human A549 Lung Carcinoma Cells

1999 ◽  
Vol 19 (3) ◽  
pp. 1938-1949 ◽  
Author(s):  
Frédéric Bost ◽  
Robert McKay ◽  
Myriam Bost ◽  
Olga Potapova ◽  
Nicholas M. Dean ◽  
...  
Keyword(s):  
Steady State ◽  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Protein Expression ◽  
Lung Carcinoma ◽  
Soft Agar ◽  
Carcinoma Cells ◽  
Lung Carcinoma Cells ◽  
Epidermal Growth ◽  
A549 Lung

ABSTRACT We have previously found that epidermal growth factor (EGF) mediates growth through the Jun N-terminal kinase/stress-activated kinase (JNK/SAPK) pathway in A549 human lung carcinoma cells. As observed here, EGF treatment also greatly enhances the tumorigenicity of A549 cells, suggesting an important role for JNK in cancer cell growth (F. Bost, R. McKay, N. Dean, and D. Mercola, J. Biol. Chem. 272:33422–33429, 1997). Several isoforms families of JNK, JNK1, JNK2, and JNK3, have been isolated; they arise from alternative splicing of three different genes and have distinct substrate binding properties. Here we have used specific phosphorothioate oligonucleotides targeted against the two major isoforms, JNK1 and JNK2, to discriminate their roles in EGF-induced transformation. Multiple antisense sequences have been screened, and two high-affinity and specific candidates have been identified. Antisense JNK1 eliminated steady-state mRNA and JNK1 protein expression with a 50% effective concentration (EC50) of <0.1 μM but did not alter JNK2 mRNA or protein levels. Conversely, antisense JNK2 specifically eliminated JNK2 steady-state mRNA and protein expression with an EC50 of 0.1 μM. Antisense JNK1 and antisense JNK2 inhibited by 40 and 70%, respectively, EGF-induced total JNK activity, whereas sense and scrambled-sequence control oligonucleotides had no effect. The elimination of mRNA, protein, and JNK activities lasted 48 and 72 h following a single Lipofectin treatment with antisense JNK1 and JNK2, respectively, indicating sufficient duration for examining the impact of specific elimination on the phenotype. Direct proliferation assays demonstrated that antisense JNK2 inhibited EGF-induced doubling of growth as well as the combination of active antisense oligonucleotides did. EGF treatment also induced colony formation in soft agar. This effect was completely inhibited by antisense JNK2 and combined-antisense treatment but not altered by antisense JNK1 alone. These results show that EGF doubles the proliferation (growth in soft agar as well as tumorigenicity in athymic mice) of A549 lung carcinoma cells and that the JNK2 isoform but not JNK1 is utilized for mediating the effects of EGF. This study represents the first demonstration of a cellular phenotype regulated by a JNK isoform family, JNK2.

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