IMMUNOHISTOCHEMICAL LOCALIZATION OF GLUCOSE TRANSPORTERS IN HUMAN RENAL-CELL CARCINOMA

The localization of 2 isoforms of glucose transporters (GLUT1 and GLUT4) in 75 patients with renal cell carcinoma was examined immunohistochemically. Paraffin sections were immunostained with either anti-GLUT1 or GLUT4 antibody by the avidin-biotin-peroxidase complex method. In 55 of 75 patients, GLUT1 staining was demonstrated at the plasma membrane of the cancer cells. In the clear cell subtype, 44 of 52 (84.6%) patients were positive for GLUT1. We did not detect positive staining for GLUT1 in the spindle cell type. In the mixed cell subtype, positive staining was recognized in only the areas of clear cell carcinomas (10 of 13; 76.9%). Positive staining for GLUT1 did not show any significant correlation with tumor grade or extent. Heterogeneous expression of GLUT1 was observed in tumor cell mass: some tumor cells were positive for GLUT1, while other cells were not. In adjacent normal tissue, GLUT1 staining was only recognized at the plasma membrane of some renal tubules. GLUT4 staining was not recognized in either tumor or normal tissues.