In addition to alterations in oxygen concentration associated with hypoxic microenvironments, glucose concentration gradients found in tumors also influence the rate of aerobic and anaerobic glycolysis. A carbohydrate-response element (ChoRE) is responsible for regulating glycolytic enzyme gene expression in response to changing glucose concentrations through a binding interaction at the same consensus sequence as HIF-1. Interactions of HIF-1 and ChoRE with the DNA sequence 5’-RCGTG-3’ leads to increased expression of genes listed above.[8]