There were several hot targeting drugs in breast cancer treatment, comprising the HER-2-targeting monoclonal antibody (mAb), CDK4/6 inhibitor, poly ADP-ribose polymerase (PARP) inhibitor, PI3K/AKT/mTOR pathway inhibitor, ER targeting drugs, and aromatase inhibitor (AI). Here, CYP19A1 is linked to breast cancer.