MON-133 - Progesterone-Mediated Regulation of Neuregulin-1 and Erbb Receptors in Human Uterine Stromal Cells

Neuregulin-1 (NRG1), a member of the EGF-like growth factor family, is well recognized for its roles in cardiac, neural, and cancer biology. However, the role of NRG1 in uterine physiology and progesterone (P4)-mediated endometrial remodeling remains poorly understood. Given that the uterus undergoes cyclical, P4-driven tissue remodeling, elucidating how NRG1 is regulated could uncover novel mechanisms supporting endometrial function. Therefore, to understand the expression patterns of NRG1 and its receptors, ErbB2 and ErbB3, protein expression was examined in human uterine tissue sections using immunohistochemistry (IHC), along with stromal (CD105) and epithelial (E-cadherin) markers. IHC analysis revealed that NRG1 and ErbB2/3 strongly colocalized in the endometrium along with CD105 and E-cadherin.

In further studies, human stromal cells (hSCs) were cultured and treated with exogenous P4 in a dose-dependent and time-dependent manner. This was followed by analysis of NRG1, ErbB2, and ErbB3 expression using reverse transcription semi-quantitative polymerase chain reaction (RT-PCR). Under these experimental conditions, NRG1, ErbB2, and ErbB3 expression was P4 dose- and time-dependent. Moreover, immunocytochemical (ICC) analysis demonstrated strong immunolocalization of NRG1 and its receptors, ErbB2 and ErbB3, in hSCs. These preliminary studies suggest that NRG1 and ErbB2/ErbB3 expression in the uterine endometrium and hSCs is modulated in a P4-dependent manner and may contribute to endometrial remodeling in preparation for implantation.

*Unless otherwise noted, all abstracts presented at ENDO must not be released to the press or the public until the date and time of presentation. For oral presentations, the abstracts are embargoed until the session begins. The Endocrine Society reserves the right to lift the embargo on specific abstracts that are selected for promotion prior to or during ENDO.*