GPER1 and cancer: Ligand-activated GPER triggers the rapid activation of transduction pathways such as epidermal growth factor receptor (EGFR) and mitogen-activated protein kinases (MAPKs), leading to a specific gene signature and the migration and proliferation of cancer cells and CAFs (Albanito et al., 2007; Lappano et al., 2014; Pandey et al., 2009; Prossnitz and Maggiolini, 2009; Santolla et al., 2012).