Human erythrocyte glucose transporter (Glut1) is immunohistochemically detected as a late event during malignant progression in Barrett's metaplasia

We have previously demonstrated that the human erythrocyte glucose transporter (Glut1) is expressed in adenocarcinoma arising in Barrett's metaplasia (BM). We have also shown that Glut1 is expressed as a late event during colorectal carcinogenesis. The aim of this work was to determine the chronology of Glut1 expression during the neoplastic progression in Barrett's metaplasia. Formalin-fixed, paraffin-embedded tissue sections of 251 biopsies from 97 patients with BM were immunostained with the anti-Glut1 antibody MYM, after microwave-aided antigen retrieval, using the standard avidin-biotin complex immunoperoxidase technique. Dysplasia was graded as negative (ND), low grade (LGD)/indefinite or high grade (HGD). None of the 181 biopsies with ND (0%) or 51 biopsies with LGD (0%) showed Glut1 immunoreactivity. More importantly, although 0 of 6 biopsies with HGD (0%) expressed Glut1, 9 of 13 biopsies with adenocarcinoma (69%) were Glut1 positive (P = 0.0108, Fisher's exact test). Our results indicate that Glut1 is expressed as a late event during the neoplastic progression in BM. Prospective studies are needed to determine the clinical utility of Glut1 immunoreactivity as a marker of carcinoma in patients with BM.