Estrogen mediated epithelial proliferation in the uterus is directed by stromal Fgf10 and Bmp8a. (15th January 2015)

• Record Type: Journal Article
• Authors: Chung, Daesuk; Gao, Fei; Jegga, Anil G.; Das, Sanjoy K.
• Is Part Of: Molecular and cellular endocrinology. Volume 400(2015)
• Page Start: 48
• Page End: 60
• Publication Date: 2015-01-15
• Subjects: Uterus -- Estrogen -- Epithelial -- Stromal -- Paracrine -- Proliferation; Endocrinology -- Periodicals; Molecular biology -- Periodicals; Cytology -- Periodicals; Endocrinology -- Periodicals; Hormones -- Periodicals; Endocrinologie -- Périodiques; Cytology; Endocrinology; Molecular biology; Periodicals; 573.4
• DOI: 10.1016/j.mce.2014.11.002
• Languages: English
• ISSNs: 0303-7207

Abstract

Highlights: Epithelial–stromal co-culture systems are used to study uterine estrogen signaling. Microarray studies have found stromal factors for epithelial control by estrogen. Molecular suppression has identified Bmp8a and Fgf10 in paracrine communication. Bmp8a/Fgf10 controls epithelial proliferation and ligand–receptor signaling. Ligand–receptor signaling is detected in the uterine epithelium of mice by estrogen. Abstract: To define endometrial stromal-derived paracrine mediators that participate in estradiol-17β (E2)-induced epithelial proliferation, microarray analysis of gene expression was carried out in mouse uterine epithelial–stromal co-culture systems under the condition of E2 or vehicle (control). Our results demonstrated gene alteration by E2: in epithelial cells, we found up-regulation of 119 genes and down-regulation of 28 genes, while in stroma cells we found up-regulation of 144 genes and down-regulation of 184 genes. A functional enrichment analysis of the upregulated epithelial genes implicated them for proliferation, while upregulated stromal genes were associated with extracellular functions. Quantitative RT-PCR and in situ hybridization results confirmed differential gene expression in both cell cultures and ovariectomized uteri after the above treatments. Based on our identification of stromal secretory factors, we found evidence that suppression by siRNA specifically for Bmp8a and/or Fgf10 in the stromal layer caused significant inhibition of proliferation by E2 in the co-culture system, suggesting Bmp8a and Fgf10 act as paracrine mediators during E2-dependent control of uterine proliferation. The localization of receptors and receptor activation signaling in epithelial cells in both the co-culture system and uteri was consistent with their involvement in ligand–receptor signaling. Interestingly, loss of Bmp8a or Fgf10 also caused abrogation of E2-regulated epithelial receptor signaling in co-culture systems, suggesting that stroma-derived Fgf10 and Bmp8a are responsible for epithelial communication. Overall, stromal Fgf10 and Bmp8a serve as potential paracrine factors for E2-dependent regulation of epithelial proliferation in the uterus.