SLC2A1 and neoplasm: p53 can transcribe target genes required for oxidative phosphorylation, such as SCO2,92 or genes that inhibit glycolysis, such as TIGAR and Parkin.93,94 p53 binds to G6PDH, the rate-limiting enzyme of the pentose phosphate pathway, to further inhibit the activated pentose phosphate pathway in tumor cells.95,96 p53 inhibits glucose uptake and glycolysis by suppressing the expression and translocation of glucose transporter proteins such as GLUT1 and GLUT4.97 Glycolysis and gluconeogenesis can be considered reversible processes to some extent.