Gene Set Enrichment Analysis (GSEA) revealed that the HALLMARK REACTIVE OXYGEN SPECIES pathway genes were highly enriched in NRF2-silenced HNSCC cells and that there was a concomitant decrease in the expression of a panel of NRF2-mediated antioxidant genes (Figure 4A). This evidence concerns the gene NFE2L2 and head and neck squamous cell carcinoma.