It has been previously described that activation of the B1 and B2 receptors by their agonists LDBK and BK induces proliferation in estrogen-sensitive breast cancer cells (MCF7 and ZR-75-1 cells) and primary culture of breast cancer cells, which is mediated by the activation of ERK1/2 and is dependent on EGFR transactivation [16,17]. Here, MAPK3 is linked to breast cancer.