Early Growth Response 1, (EGR1) belongs to the EGR family of zinc finger transcription factors and regulates the expression of several tumor suppressors. EGR1 appears to activate transcription by binding to DNA as a monomer. The expression of EGR1 is induced by diverse signals that initiate growth and differentiation. EGR1 also plays a role in tumor growth angiogenesis. EGR1 suppresses or activates cell growth depending on the tumor type. Within the region that includes its three zinc finger domains, human EGR1 shares 99% aa sequence identity with mouse EGR1 and rat EGR1.