کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
9245188 1209942 2005 18 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Epidermal Growth Factor Receptor: A Novel Target of the Wnt/β-Catenin Pathway in Liver
موضوعات مرتبط
علوم پزشکی و سلامت پزشکی و دندانپزشکی بیماری‌های گوارشی
پیش نمایش صفحه اول مقاله
Epidermal Growth Factor Receptor: A Novel Target of the Wnt/β-Catenin Pathway in Liver
چکیده انگلیسی
Background & Aims: Wnt/β-catenin activation is observed in normal liver development, regeneration, and liver cancer. Our aim was to elucidate the regulation and mechanism of this pathway in liver. Methods: We report the generation and characterization of liver-specific nonmutated β-catenin-overexpressing transgenic mice. Transgenic livers were examined for their morphology and phenotype by histology, proliferation, apoptosis, and microarray analysis. Results: Transgenic livers displayed a significant increase in cytoplasmic, membranous, and nuclear β-catenin in hepatocytes as compared with their wild-type littermates, which display a predominant membranous localization only. A 15%-20% increase in the liver weight-body weight ratio was evident in transgenic mice secondary to increased hepatocyte proliferation. Microarray analysis showed differential expression of approximately 400 genes in the transgenic livers. Epidermal growth factor receptor RNA and protein and increased levels of activated epidermal growth factor receptor and Stat3 were observed in the transgenic livers. Epidermal growth factor receptor promoter analysis showed a T-cell factor-binding site, and subsequent reporter assay confirmed epidermal growth factor receptor activation in response to Wnt-3A treatment that was abrogated by frizzled related protein 1, a known Wnt antagonist. Epidermal growth factor receptor inhibition successfully decreased liver size in transgenic mice. Next, 7 of 10 hepatoblastomas displayed simultaneous β-catenin and epidermal growth factor receptor up-regulation, thus suggesting a strong relationship between these 2 proteins in tumors. Conclusions: β-Catenin transgenic mice show an in vivo hepatotrophic effect secondary to increased basal hepatocyte proliferation. Epidermal growth factor receptor seems to be a direct target of the pathway, and epidermal growth factor receptor activation might contribute toward some mitogenic effects of increased β-catenin in liver: epidermal growth factor receptor inhibition might be useful in such states.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Gastroenterology - Volume 129, Issue 1, July 2005, Pages 285-302
نویسندگان
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