Diethylstilbestrol regulates trophoblast stem cell differentiation as a ligand of orphan nuclear receptor ERRβ

Abstract

The orphan nuclear receptor ERRβ is expressed in undifferentiated trophoblast stem cell lines and extraembryonic ectoderm, and genetic ablation of ERRβ results in abnormal trophoblast proliferation and precocious differentiation toward the giant cell lineage. Here, we show that the synthetic estrogen diethylstilbestrol (DES) promotes coactivator release from ERRβ and inhibits its transcriptional activity. Strikingly, treatment of trophoblast stem cells with DES led to their differentiation toward the polyploid giant cell lineage. In addition, DES-treated pregnant mice exhibited abnormal early placenta development associated with an overabundance of trophoblast giant cells and an absence of diploid trophoblast. These results define a novel pathway for DES action and provide evidence for steroidlike control of trophoblast development.