Wu et al. found AhR expression to be correlated negatively with N-myc proto-oncogene (MYCN) expression and highly correlated with the histology grade of differentiation in human neuroblastoma tissues, suggesting that the AhR regulates the expression and function of MYCN upstream through modulation of E2F transcription factor 1 (147). The gene discussed is MYCN; the disease is neuroblastoma.