In addition, several studies have revealed that a member of the G-protein coupled receptor family, named GPR30 (also known as GPER), is also able to mediate estrogen signaling in diverse types of normal and malignant cells, including breast cancer cells and CAFs derived from breast tumor patients (Madeo and Maggiolini, 2010; Maggiolini and Picard, 2010). This evidence concerns the gene GPER1 and breast neoplasm.