For example, β-adrenergic signaling has been implicated in promoting EMT and increasing the metastatic potential in cancer cells via the VEGF/MMP and STAT3/ERK/MAPK pathways.321 Furthermore, Sloan et al. found that both stress-induced and pharmacological β-adrenergic stimulation promoted macrophage migration into tumor tissue in a mouse model of breast cancer. Here, STAT3 is linked to cancer.