The aryl hydrocarbon receptor (AhR) is a transcription factor (part of the group of nuclear receptors) that responds to the presence of aromatic hydrocarbons. It regulates genes involved xenobiotic metabolism, e.g. cytochrome P450 enzymes.
Proteins on this pathway have targeted assays available via the [https://assays.cancer.gov/available_assays?wp_id=WP2873 CPTAC Assay Portal]