SnoN oncoprotein enhances estrogen receptor-α transcriptional activity

► SnoN enhances ERα signaling and ERα target gene expression. ► SnoN interacts with ERα at the TTF1 (pS2) promoter. ► SnoN increases the proliferation of MCF7 breast cancer cells. ► The results reveal a novel crosstalk between ERα and TGF-β signaling pathways.