UGE and UGM Reveal Novel Signaling Pathways and Ligand-Receptor Interactions in the Primitive Prostate Stem Cell Niche

We isolated fetal murine urogenital sinus epithelium and urogenital sinus mesenchyme and determined their global gene expression profiles to define their differentially expressed regulators. To distinguish gene expression patterns that are shared by other developing epithelial/mesenchymal compartments in the embryo from those that pertain to the prostate stem cell niche, we also determine the global gene expression of epidermis and dermis of the same embryos. We identified a distinctive core of transcripts that were differentially regulated in the prostate stem cell niche. Our analysis indicates that several of the key transcriptional components that are likely to be active in the embryonic prostate stem cell niche regulate processes such as self-renewal (e.g., E2f and Ap2), lipid metabolism (e.g., Serbp1) and cell migration (e.g., Areb6 and Rreb1). Several of the promoter binding motifs that are enriched in the profiles are shared between the prostate epithelial/mesenchymal compartments and their epidermis/dermis counterparts, indicating their likely relevance in epithelial/mesenchymal signaling in primitive cellular compartments. We also focused on defining ligand-receptor interactions that may be relevant in controlling signals in the stem cell niche and identified the Wnt/beta-catenin, ephrin, Notch, sonic hedgehog, FGF, TGF-beta and bone morphogenic signaling pathways as being of likely relevance in the prostate stem cell niches. Members of the integrins family including those that bind extracellular matrix proteins such as laminin and activate latent TGF-beta are also expressed in the prostate niche.development.

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Blum R, Gupta R, Burger PE, Ontiveros CS, Salm SN, Xiong X, Kamb A, Wesche H, Marshall L, Cutler G, Wang X, Zavadil J, Moscatelli D, Wilson EL