AHR and cancer: For example, the AHR is hyper-expressed and “constitutively” active (likely a reflection of the presence of endogenous AHR ligands [13,17,18]) in a diverse array of human cancers including glioblastomas [18], adult T cell leukemias, and oral cavity, lung, liver, prostate and Her2+ breast adenocarcinomas [6,17,18,19,20,21,22,23,24,25].