Fig. 6.

Proposed mechanism responsible for VEGF regulation by the AhR in the TRAMP. When the AhR is present in TRAMP mice with diffuse epithelial hyperplasia, the AhR would interact with and sequester ARNT, minimizing the ability of ARNT to interact with stabilized HIF-1 to induce VEGF production. The net effect would be to effectively diminish likelihood of tumor growth. When the AhR is absent, ARNT would be free to interact with stabilized HIF-1 to stimulate VEGF production, resulting in a greater likelihood of tumor growth.