Estrogen receptor β stimulates Egr-1 transcription via MEK1/Erk/Elk-1 cascade in C6 glioma cells

The Egr-1 is an immediate early response gene encoding a transcription factor that functions in the regulation of cell growth, differentiation, and apoptosis. Estrogen has diverse physiological effects, including cellular proliferation and neuroprotection against brain injury. There are two types of estrogen receptors (ERs), ERα and ERβ. ERα-induced Egr-1 expression has been extensively studied; however, the role of ERβ is yet not known. In the present study, we investigated whether or not ERβ induces Egr-1 expression in C6 rat glioma cells, which express ERβ but not ERα. Our results show that ERβ promoted up-regulation of Egr-1 expression via a non-genomic mechanism involving the Raf/MEK1/Erk/Elk-1 signaling cascade.