- Corre, Sébastien;
- Tardif, Nina;
- Mouchet, Nicolas;
- Leclair, Héloïse M;
- Boussemart, Lise;
- Gautron, Arthur;
- Bachelot, Laura;
- Perrot, Anthony;
- Soshilov, Anatoly;
- Rogiers, Aljosja;
- Rambow, Florian;
- Dumontet, Erwan;
- Tarte, Karin;
- Bessede, Alban;
- Guillemin, Gilles J;
- Marine, Jean-Christophe;
- Denison, Michael S;
- Gilot, David;
- Galibert, Marie-Dominique
BRAF inhibitors target the BRAF-V600E/K mutated kinase, the driver mutation found in 50% of cutaneous melanoma. They give unprecedented anti-tumor responses but acquisition of resistance ultimately limits their clinical benefit. The master regulators driving the expression of resistance-genes remain poorly understood. Here, we demonstrate that the Aryl hydrocarbon Receptor (AhR) transcription factor is constitutively activated in a subset of melanoma cells, promoting the dedifferentiation of melanoma cells and the expression of BRAFi-resistance genes. Typically, under BRAFi pressure, death of BRAFi-sensitive cells leads to an enrichment of a small subpopulation of AhR-activated and BRAFi-persister cells, responsible for relapse. Also, differentiated and BRAFi-sensitive cells can be redirected towards an AhR-dependent resistant program using AhR agonists. We thus identify Resveratrol, a clinically compatible AhR-antagonist that abrogates deleterious AhR sustained-activation. Combined with BRAFi, Resveratrol reduces the number of BRAFi-resistant cells and delays tumor growth. We thus propose AhR-impairment as a strategy to overcome melanoma resistance.