Estrogen is a growth factor that stimulates cell proliferation. The effects of estrogen are
mediated through the estrogen receptors, ERα and ERβ, which function as ligand-induced
transcription factors and belong to the nuclear receptor superfamily. On the other hand, TGF-
β acts as a cell growth inhibitor, and its signaling is transduced by Smads. Although a
number of studies have been made on the cross-talk between estrogen/ERα and TGF-
β/Smad signaling, whose molecular mechanisms remain to be determined. Here, we show …