Wide expression of the human erythrocyte glucose transporter Glut1 in human cancers.

Glucose uptake has been found to be increased in cancer cells. Previous work has shown increased expression of the human erythrocyte glucose transporter (Glut1) mRNA in some human cancers, indicating that Glut1 may play a significant role in glucose uptake by these tumors. The distribution of Glut1 protein in normal and malignant human tissues is still largely unknown. Using immunohistochemistry, we found that Glut1 is largely undetectable in normal epithelial tissues and benign epithelial tumors but is expressed in a significant proportion of a variety of human carcinomas. We hypothesize that Glut1 expression by human carcinomas indicates an increased glucose uptake, and probably increased utilization of energy, which may correlate with an aggressive behavior. The biological significance of Glut1 expression needs to be determined.