Does human endometrial LGR5 gene expression suggest the existence of another hormonally regulated epithelial stem cell niche?

In this study, we used the gold standard method,in situ hybridisation (ISH) along with qPCR and a systems biology approach to study the location ofLGR5 gene expression in full thickness human endometrium and Fallopian tubes. The progesterone regulation of endometrialLGR5 was examinedin vivo and in short-term cultured endometrial tissue explantsin vitro.LGR5 expression was correlated with epithelial proliferation (Ki67), and expression of previously reported epithelia progenitor markers (SOX9 and SSEA-1) immunohistochemistry (IHC).MAIN RESULTS AND THE ROLE OF CHANCELGR5 gene expression was significantly higher in the endometrial luminal epithelium than in all other epithelial compartments in the healthy human endometrium, including the endometrial stratum basalis (P< 0.05). The strongest SSEA-1 and SOX9 staining was observed in the stratum basalis glands, but the general trend of SOX9 and SSEA-1 expression followed the same cyclical pattern of expression asLGR5. Stratum functionalis epithelial Ki67-LI andLGR5 expression levels correlated significantly (r = 0.74,P = 0.01), however, they did not correlate in luminal and stratum basalis epithelium (r = 0.5 and 0.13, respectively). EndometrialLGR5 demonstrates a dynamic spatiotemporal expression pattern, suggesting hormonal regulation. Oral and local progestogens significantly reduced endometrialLGR5 mRNA levels compared with women not on hormonal treatment (P< 0.01). Our data were in agreement within silico analysis of publ...
Source: Human Reproduction - Category: Reproduction Medicine Source Type: research