AR overexpression, particularly β2-AR overexpression, was found to be correlated with poor prognosis of ER− breast cancer patients in a recent study by Kurozumi et al.21, where immune biomarkers, such as the grades of tumor-infiltrating lymphocytes and programmed death ligand 1 expression, were shown to be significantly reduced in these patients. Here, ADRB2 is linked to breast carcinoma.