IMMUNOHISTOCHEMICAL LOCALIZATION OF GLUCOSE TRANSPORTERS IN HUMAN RENAL-CELL CARCINOMA

The localization of 2 isoforms of glucose transporters (GLUT1 and GLUT 4) in 75 patients with renal cell carcinoma was examined immunohistoch emically. Paraffin sections were immunostained with either anti-GLUT1 or GLUT4 antibody by the avidin-biotin-peroxidase complex method. In 5 5 of 75 patients, GLUT1 staining was demonstrated at the plasma membra ne of the cancer cells. In the clear cell subtype, 44 of 52 (84.6%) pa tients were positive for GLUT1. We did not detect positive staining fo r 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 significa nt 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, GLU T1 staining was only recognized at the plasma membrane of some renal t ubules. GLUT4 staining was not recognized in either tumor or normal ti ssues.