AHR immunoreactivity analysis of tissues from cancer patients revealed increased expression levels of AHR in breast (Saito et al. 2014), esophageal (Zhang et al. 2012), gastric (Peng et al. 2009b), pancreatic (Koliopanos et al. 2002), prostate (Richmond et al. 2014), lung (Su et al. 2013; Portal-Nuñez et al. 2012), liver (Liu et al. 2013), and urothelial carcinoma (Ishida et al. 2010) as well as glioblastomas (Gramatzki et al. 2009), as compared to its expression in surrounding normal tissues. Here, AHR is linked to cancer.