Glucose transporter 5 (GLUT5) is a membrane transporter that specifically transports fructose and plays a key role in dietary fructose uptake and metabolism. In recent years, a high fructose diet has occupied an important position in the daily intake of human beings, resulting in a significant increase in the incidence of obesity and metabolic diseases worldwide. Over the past few decades, GLUT5 has been well understood to play a significant role in the pathogenesis of human digestive diseases. Recently, the role of GLUT5 in human cancer has received widespread attention, and a large number of studies have focused on exploring the effects of changes in GLUT5 expression levels on cancer cell survival, metabolism and metastasis. However, due to various difficulties and shortcomings, the molecular structure and mechanism of GLUT5 have not been fully elucidated, which to some extent prevents us from revealing the relationship between GLUT5 expression and cell carcinogenesis at the protein molecular level. In this review, we summarize the current understanding of the structure and function of mammalian GLUT5 and its relationship to intestinal diseases and cancer and suggest that GLUT5 may be an important target for cancer therapy.

Glucose transporter 5 (GLUT5) is the only membrane transporter that specifically transports fructose in the human body. GLUT5 is mainly expressed in small intestinal epithelial cells and plays an important role in dietary fructose uptake and metabolism. In recent years, with the continuous improvement of living standards, the global per capita fructose intake has increased dramatically, resulting in a gradual increase in obesity and metabolic diseases. Due to the critical role of GLUT5 in dietary fructose absorption and metabolism, the relationship between GLUT5 and human diseases is receiving increasing attention. Increasing evidence suggests that GLUT5 plays a significant role in diseases ranging from digestive system diseases to a variety of human cancers. However, due to various difficulties and shortcomings, the molecular structure of GLUT5 has not been fully elucidated. Further understanding of the molecular structure and biological function of GLUT5 will help us to better understand the mechanism of GLUT5-related diseases and design more targeted therapeutic drugs. In this review, we mainly introduce the molecular structure and transport mechanism of mammalian GLUT5, and provide an outlook for potential application of GLUT5 from the perspective of basic molecular biology, in order to provide a better strategy for the clinical treatment of fructose metabolism-related diseases.