Expression of facilitative glucose transport proteins during development of squamous cell carcinomas of the head and neck

Positron emission tomography studies on malignant head and neck tumors have shown that tumor growth and elevated glucose uptake are associated. On a m olecular level, glucose uptake is mediated by specific glucose transport pr oteins, which exhibit an altered expression in head and neck malignant neop lasms. However, it is unknown when during development of squamous cell carc inomas an alteration of the expression of glucose transport proteins occurs . We have studied the expression of different facilitating glucose transpor t proteins (GLUT 1,2, 3 and 4) by immunohistochemistry in a variety of pren eoplastic and neoplastic mucosal lesions of the head and neck. We have obse rved weak expression of GLUT I in normal mucosa, a marked expression of GLU T I throughout preneoplastic lesions, which correlated well with the degree of dysplasia. In squamous cell carcinomas of the head and neck (HNSCC) and metastases, GLUT I was always expressed strongly. In contrast, GLUT 2, 3 a nd 4 were not detected in any of the epithelial tissues examined. The incre ased expression of GLUT I in dysplastic lesions and its sustained expressio n in SCC indicate that changes of GLUT I expression are early events during development of HNSCC. Therefore, the detection of GLUT I might be a reliab le marker in the diagnosis of premalignant lesions of the oropharyngeal muc osa. (C) 1999 Wiley-Liss, Inc.