NRF2 up-regulates the pentose phosphate pathway (PPP) enzyme, glucose-6-phosphate dehydrogenase (G6PD) and transketase (TKT) mediated nucleotide biosynthesis, thereby promoting the malignant progression of head and neck squamous cell carcinoma (HNSCC) (26). Here, G6PD is linked to head and neck squamous cell carcinoma.