Epidermal Growth Factor Inhibits Somatostatin-Induced Apoptosis

1999 ◽  
Vol 81 (1) ◽  
pp. 95-100 ◽  
Author(s):  
Jon S. Thompson
Keyword(s):  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Epidermal Growth ◽  
Induced Apoptosis

Apoptosis in human cultured trophoblasts is enhanced by hypoxia and diminished by epidermal growth factor

2000 ◽  
Vol 278 (5) ◽  
pp. C982-C988 ◽  
Author(s):  
Roni Levy ◽  
Steven D. Smith ◽  
Kala Chandler ◽  
Yoel Sadovsky ◽  
D. Michael Nelson
Keyword(s):  
Cell Differentiation ◽  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Fetal Growth ◽  
Fetal Growth Restriction ◽  
Caspase Inhibitor ◽  
Trophoblast Differentiation ◽  
Epidermal Growth ◽  
Induced Apoptosis

Preeclampsia and fetal growth restriction are associated with placental hypoperfusion and villous hypoxia. The villous response to this environment includes diminished trophoblast differentiation and enhanced apoptosis. We tested the hypothesis that hypoxia induces apoptosis in cultured trophoblasts, and that epidermal growth factor (EGF), an enhancer of trophoblast differentiation, diminishes hypoxia-induced apoptosis. Trophoblasts isolated from placentas of term-uncomplicated human pregnancies were cultured up to 72 h in standard ([Formula: see text]= 120 mmHg) or hypoxic ([Formula: see text] < 15 mmHg) conditions. Exposure to hypoxia for 24 h markedly enhanced trophoblast apoptosis as determined by DNA laddering, internucleosomal in situ DNA fragmentation, and histomorphology, as well as by the reversibility of the apoptotic process with a caspase inhibitor. Apoptosis was accompanied by increased expression of p53 and Bax and decreased expression of Bcl-2. Addition of EGF to cultured trophoblasts or exposure of more differentiated trophoblasts to hypoxia significantly lowered the level of apoptosis. We conclude that hypoxia enhances apoptosis in cultured trophoblasts by a mechanism that involves an increase in p53 and Bax expression. EGF and enhancement of cell differentiation protect against hypoxic-induced apoptosis.

scholarly journals Amphiregulin impairs apoptosis-stimulating protein 2 of p53 overexpression–induced apoptosis in hepatoma cells

Tumor Biology ◽  
2017 ◽  
Vol 39 (3) ◽  
pp. 101042831769502 ◽  
Author(s):  
Kai Liu ◽  
Dongdong Lin ◽  
Yabo Ouyang ◽  
Lijun Pang ◽  
Xianghua Guo ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Epidermal Growth Factor Receptor ◽  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Hepg2 Cells ◽  
Apoptotic Cell ◽  
Growth Factor Receptor ◽  
Hepatoma Cells ◽  
Epidermal Growth ◽  
Induced Apoptosis

Overexpression of apoptosis-stimulating protein 2 of p53 (ASPP2) induces apoptotic cell death in hepatoma cells (e.g. HepG2 cells) by enhancing the transactivation activity of p53, but long-term ASPP2 overexpression fails to induce more apoptosis since activation of the epidermal growth factor/epidermal growth factor receptor/SOS1 pathway impairs the pro-apoptotic role of ASPP2. In this study, in recombinant adenovirus-ASPP2-infected HepG2 cells, ASPP2 overexpression induces amphiregulin expression in a p53-dependent manner. Although amphiregulin initially contributes to ASPP2-induced apoptosis, it eventually impairs the pro-apoptotic function of ASPP2 by activating the epidermal growth factor/epidermal growth factor receptor/SOS1 pathway, leading to apoptosis resistance. Moreover, blocking soluble amphiregulin with a neutralizing antibody also significantly increased apoptotic cell death of HepG2 cells due to treatment with methyl methanesulfonate, cisplatin, or a recombinant p53 adenovirus, suggesting that the function of amphiregulin involved in inhibiting apoptosis may be a common mechanism by which hepatoma cells escape from stimulus-induced apoptosis. Thus, our data elucidate an apoptosis-evasion mechanism in hepatocellular carcinoma and have potential implications for hepatocellular carcinoma therapy.

scholarly journals Up-regulation of α2β1 integrin cell-surface expresssion protects A431 cells from epidermal growth factor-induced apoptosis

2000 ◽  
Vol 87 (3) ◽  
pp. 360-367 ◽  
Author(s):  
Sophia Smida Rezgui ◽  
Stéphane Honore ◽  
Jean-Baptiste Rognoni ◽  
Pierre-Marie Martin ◽  
Claude Penel
Keyword(s):  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Cell Surface ◽  
A431 Cells ◽  
Epidermal Growth ◽  
Induced Apoptosis ◽  
Α2β1 Integrin

Insulin-like growth factor-1 receptor/epidermal growth factor receptor (EGFR) heterodimerization and resistance to epidermal growth factor receptor tyrosine kinase inhibitors in non-small-cell lung cancer

2006 ◽  
Vol 24 (18_suppl) ◽  
pp. 13032-13032 ◽  
Author(s):  
F. Morgillo ◽  
W. K. Hong ◽  
H. Lee
Keyword(s):  
Lung Cancer ◽  
Epidermal Growth Factor Receptor ◽  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Kinase Inhibitors ◽  
Growth Factor Receptor ◽  
Small Cell Lung ◽  
Epidermal Growth ◽  
Induced Apoptosis ◽  
Egfr Tkis

13032 Background: Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) have been used to treat lung cancers, but resistance to these agents has been observed. This study was designed to investigate whether the insulin-like growth factor (IGF)-mediated signaling pathway induces resistance to the EGFR TKIs in lung cancer. Methods: The antitumor activities and action mechanisms of EGFR inhibitors (erlotinib, gefinitib, cetuximab), single or in combination with IGF-IR inhibitors, were assessed in vitro in a subset of non-small-cell lung cancer (NSCLC) cell lines by the MTT assay, flow cytometry-based TUNEL assay, soft agar, confocal microscopy, metabolic labeling, coimmunoprecipitation, and northern and western blot analyses, and in vivo in animal models. Correlation of EGFR and IGF-1R expression was assessed using lung tissues from patients with NSCLC. Results: EGFR TKI inhibited the proliferation and anchorage-dependent and -independent colony-forming ability of NSCLC cells, which induced apoptosis, only when IGF-1R signaling was blocked. Treatment with EGFR TKIs, but not with the EGFR antibody, induced EGFR:IGF-1R heterodimerization on cell surface and activation of the IGF-1R, resulting in the stimulation of PI3K/Akt/ mTOR pathway, promoting the de novo protein biosynthesis of survivin and EGFR, resulting in the survival of NSCLC cells. When IGF-IR and mTOR were blocked, treatment of EGFR-TKIs induced apoptosis in NSCLC cells, resulting in suppression of the NSCLC tumor growth. When we tested the expression of IGF-R and EGFR in human lung tissue, 9/14 tumor samples exhibited increased expression of EGFR and 7/9 samples showed a correlative increases in IGF-IR protein levels compared to their paired normal counterparts. Conclusions: These findings suggest that simultaneous targeting of EGFR and IGF-1R signaling pathways might be an effective therapeutic strategy against NSCLC. No significant financial relationships to disclose.

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