Glucose is a major metabolic substrate required for cancer cell survival and growth.Instead,the entry of glucose molecules into the cells is effected by a large family of structurally related transport proteins known as glucose transporters.Two main types of glucose transporters have been identified,namely,the passive facilitative glucose transporters(GLUTs) and the secondary active sodium-coupled glucose transporters(SGLTs).However,tumor cells may adapt to an ischemic microenvironment by upregulation of SGLTs in the plasma membrane which supplies the tumor cell with glucose even at very low extracellular glucose concentration.Therefore,SGLTs is essential for ischemic and hypoxic tumor cells to uptake glucose.Current research indicates that SGLTs may become a promising biomarker for cancer therapy.