Hypoxia also activated the PPP to produce required molecules such as 6-phosphogluconate, ribulose 5-phosphate, X5P, R5P, and sedoheptulose 7-phosphate for the synthesis of nucleic acids and FAs, promoting the resistance and progression of glioma cells by activating non-glucose metabolic pathways like the polyol pathway to increase sorbitol and fructose levels and protect cells from anoxic death [231] as fructose is an inducer of TKT activity [232]. This evidence concerns the gene TKT and central nervous system cancer.