In the presence of both receptors, as in JKT-1 seminoma cells, the suppressive effect of E2 may remain predominant because of a rapid dephosphorylation of ERK1/2 by an ER-β-dependent expression of protein phosphatase 2A, as described in neonatal rat cerebellar neurons (Belcher et al. 2005). The gene discussed is ESR2; the disease is seminoma.