TKT and cancer: Nrf2 also activates PPP enzyme transketolase (TKT), which converts glyceraldehyde-3-phosphate (G3P) and sedoheptulose-7-phosphate (S7P) into xylulose-5-phosphate (Xu5P) and R5P, in non-oxidative PPP to promote HCC by increasing antioxidants and purine biosynthesis, protecting cancer cells from reactive oxygen species toxicity [70].