MNF is a specific aryl hydrocarbon receptor (AhR) antagonist that effectively inhibits TCDD-induced AhR signaling pathway activation, attenuates TCDD-induced activation of downstream signaling molecules Akt and Erk1/2 and TGFalpha expression, and reverses the anti-apoptotic effect of TCDD. It is commonly used in research on AhR-related functions and signaling pathways.