It’s noteworthy that deletion of AHR in macrophages strongly correlates with the prevention of breast cancer metastasis to the lung, indicating a promising target for controlling cancer metastasis.8 Recently, clinical trial results of the AHR inhibitor, BAY 2416964, in the treatment of various solid tumors have not met anticipated success (ClinicalTrials.gov ID: NCT04069026). The gene discussed is AHR; the disease is breast cancer.