Early growth response 1 (EGR1) is an early response transcriptional regulator that can be rapidly induced by various environmental stimuli, the increase of EGR1 expression in epithelial cells is a common stress induced, cell type specific response upon host-bacteria interaction that is mediated by EGFR-ERK1/2 and beta1-integrin signaling. Early growth response 1 (Egr1) is a key transcription factor that mediates the action of estrogen (E2) to establish uterine receptivity for embryo implantation. Early growth response transcription factor 1 (EGR1) is expressed in the suprachiasmatic nucleus (SCN) after light stimulation, the circadian clock in the SCN is disturbed in mice deficient of EGR1. The transcription factor EGR1 (early growth response 1) is a member of a zinc finger transcription factor family which plays an essential role in cell growth and proliferation. EGR1 expression levels in human gliomas are decreased compared with normal brain tissues, however, the patients with low EGR1 expression level showed significantly enhanced patient survival in all glioma patients. EGR1 silencing inhibited proliferation and induced G1 phase arrest in glioma cells.