On the basis of these and our previous results showing that c-fos stimulation by E2 occurs through GPR30 and requires ERα and EGFR-mediated signaling in cancer cells expressing both receptors (Albanito et al. 2007; Maggiolini et al. 2004; Vivacqua et al. 2006a, 2006b), we examined whether atrazine could act in a similar manner. Here, GPER1 is linked to cancer.