scholarly journals Activation of Thyroid Hormone Is Transcriptionally Regulated by Epidermal Growth Factor in Human Placenta-Derived JEG3 Cells

Endocrinology ◽  
2007 ◽  
Vol 149 (2) ◽  
pp. 695-702 ◽  
Author(s):  
Gianluca Canettieri ◽  
Antonella Franchi ◽  
Michele Della Guardia ◽  
Ianessa Morantte ◽  
Maria Giulia Santaguida ◽  
...  
Keyword(s):  
Growth Factor ◽  
Thyroid Hormone ◽  
Epidermal Growth Factor ◽  
Enzymatic Activity ◽  
Early Stage ◽  
First Trimester ◽  
Mrna Levels ◽  
Type Ii ◽  
Human Type ◽  
Epidermal Growth

Human type II deiodinase is a master regulator of thyroid hormone activation in several tissues. In placenta, type II deiodinase mRNA levels and enzymatic activity are elevated only during the first trimester of pregnancy and then progressively decline. During this early stage, mitogens such as epidermal growth factor (EGF) have been shown to promote the proliferation of the trophoblast by acting through multiple mechanisms. Here we show that EGF modulates transcription of human type II deiodinase gene (Dio2) through distinct signaling pathways, leading to the assembly of a heterogeneous transcription factor complex. Gene expression and deiodination assays have shown that EGF promptly induces a short-lived Dio2 mRNA and enzymatic activity. The induction is mediated by ERK and p38 kinases, as demonstrated by selective inhibition or overexpression of different mitogen-activated kinases. Reporter assays of mutant constructs indicate that EGF-induced transcriptional activity on Dio2 promoter is mediated by the cAMP response element (CRE) and does not involve the activating protein 1 site. With functional and biochemical approaches, we have demonstrated that the EGF stimulation culminates with the assembly and recruitment over the Dio2 CRE of a composite complex, which consists of c-Jun, c-Fos, and CRE-binding protein. These results further support the hypothesis that placental iodothyronine metabolism is critical during early pregnancy.

Emergence of salivary gland cell lineage diversity suggests a role for androgen-independent epidermal growth factor receptor signaling

1995 ◽  
Vol 108 (6) ◽  
pp. 2205-2212
Author(s):  
E.M. Durban ◽  
P.G. Nagpala ◽  
P.D. Barreto ◽  
E. Durban
Keyword(s):  
Salivary Gland ◽  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Egf Receptor ◽  
Cell Lineage ◽  
Mrna Levels ◽  
Receptor Signaling ◽  
Receptor Mrna ◽  
Epidermal Growth ◽  
Lineage Diversity

Diversity of cell lineages within glandular organs is generated postnatally by differentiation of committed progenitor cells. Fundamental regulatory aspects of this process are not understood. The mouse submandibular salivary gland (SSG) served as model to assess the role of epidermal growth factor (EGF) receptor signaling during emergence of cell lineage diversity. Temporal fluctuations in EGF receptor mRNA levels coincident with crucial differentiative cell lineage transitions were revealed by RNase protection analyses. Between days 2 and 5, when proacinar cells are maturing and striated duct cells emerge, EGF receptor mRNA levels were highest and all differentiating cells exhibited EGF receptor immunoreactivity. EGF receptor mRNA levels then declined sharply and immunoreactivity became confined to ductal cells. At day 11 in male mice, and days 11 and 16 in females, a second increase in EGF receptor mRNA was detected coincident with emergence of granular convoluted tubule (GCT) cells. With completion of androgen-dependent GCT cell differentiation at the onset of puberty, EGF receptor mRNA levels and intensity of immunoreactivity decreased. Androgen effects on EGF receptor mRNA or immunoreactivity could not be detected. These temporally distinct patterns of EGF receptor expression suggest that this signaling pathway is a mechanism of potential importance in emergence of cell lineage diversity in a glandular organ.

scholarly journals Asbestos-induced phosphorylation of epidermal growth factor receptor is linked to c-fos and apoptosis

1999 ◽  
Vol 277 (4) ◽  
pp. L684-L693 ◽  
Author(s):  
Christine L. Zanella ◽  
Cynthia R. Timblin ◽  
Andrew Cummins ◽  
Michael Jung ◽  
Jonathan Goldberg ◽  
...  
Keyword(s):  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Egf Receptor ◽  
Growth Factor Receptor ◽  
Direct Interaction ◽  
Mrna Levels ◽  
Binding Studies ◽  
Therapeutic Implications ◽  
Asbestos Fibers ◽  
Epidermal Growth

We examined the mechanisms of interaction of crocidolite asbestos fibers with the epidermal growth factor (EGF) receptor (EGFR) and the role of the EGFR-extracellular signal-regulated kinase (ERK) signaling pathway in early-response protooncogene (c- fos/c- jun) expression and apoptosis induced by asbestos in rat pleural mesothelial (RPM) cells. Asbestos fibers, but not the nonfibrous analog riebeckite, abolished binding of EGF to the EGFR. This was not due to a direct interaction of fibers with ligand, inasmuch as binding studies using fibers and EGF in the absence of membranes showed that EGF did not adsorb to the surface of asbestos fibers. Exposure of RPM cells to asbestos caused a greater than twofold increase in steady-state message and protein levels of EGFR ( P < 0.05). The tyrphostin AG-1478, which inhibits the tyrosine kinase activity of the EGFR, but not the tyrphostin A-10, which does not affect EGFR activity, significantly ameliorated asbestos-induced increases in mRNA levels of c- fos but not of c- jun. Pretreatment of RPM cells with AG-1478 significantly reduced apoptosis in cells exposed to asbestos. Our findings suggest that asbestos-induced binding to EGFR initiates signaling pathways responsible for increased expression of the protooncogene c- fos and the development of apoptosis. The ability to block asbestos-induced elevations in c- fos mRNA levels and apoptosis by small-molecule inhibitors of EGFR phosphorylation may have therapeutic implications in asbestos-related diseases.

scholarly journals Cardiotoxicity among Patients Using Pertuzumab, Trastuzumab and Taxane with HER2-Positive Early-Stage Breast Cancer: A Single-Centre Experience

2021 ◽  
pp. 465-474
Author(s):  
Alanood S. Algarni ◽  
Anan A. Alfi ◽  
Azuf T. Turkistani ◽  
Layal E. Malki ◽  
Nouf F. Alghanam ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Ejection Fraction ◽  
Drug Combination ◽  
Early Stage ◽  
Early Stage Breast Cancer ◽  
Her2 Positive ◽  
Human Epidermal Growth Factor ◽  
Epidermal Growth

Aim: In this study, we aimed to investigate the incidence rate, risk factors, and mortality rates in patients with early-stage breast cancer using anti-HER2 (Human epidermal growth factor receptor-2) treatment. Patients and Methods: A total of 106 patients diagnosed with human epidermal growth factor 2 (HER2)-positive early-stage breast cancer and receiving anti-HER2 treatment at King Abdulaziz Medical City (KAMC) from 2015 to 2019 were included in the analysis to assess the incidence of cardiotoxicity was collected as a retrospective study. Univariate and multivariate analyses as well as multiple exact logistic regression analysis were conducted to understand the relationships between the left ventricular ejection fraction (LVEF) and treatment combinations and comorbidities Results: The LVEF measurements using an echocardiography method at the baseline (before any treatment) and during the anti-HER2 therapy were assessed. The results suggest that the higher the drug combination, the higher the odds ratio for the declined ejection fraction (EF) patient group. Further, patients treated with the pertuzumab and trastuzumab combination were four times more likely to have a decline in their EF than those who did not use the pertuzumab and trastuzumab drug combination (OR 4.28, 95% CI [1.68–10.91]). Conclusion: This study demonstrated that the drug combination considered here is associated with reduced LVEF and, similarly, comorbidities were also related to EF. However, a larger study in a global patient population will confirm the present observations.

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