By elucidating the differential effects of PAHs and DLCs on aldo–keto reductase 1C3 expression and associated prostaglandin D2 metabolism, we here provide evidence that the epidermal growth factor receptor (EGFR) substantially shapes AHR ligand-induced responses in human epithelial cells, i.e. primary and immortalized keratinocytes and breast cancer cells. This evidence concerns the gene EGFR and breast carcinoma.