Expressions of glucose transporter Types 1 and 3 and hexokinase-II in diffuse large B-cell lymphoma and other B-cell non-Hodgkin's lymphomas

IntroductionDiffuse large B-cell lymphoma (DLBCL) has been reported to show higher uptake of 2-deoxy-2-F18-fluoro-d-glucose (FDG) by positron emission tomography than other B-cell non-Hodgkin's lymphomas (non-DLBCL). The authors addressed the mechanism of FDG uptake in DLBCL by immunostaining for glucose transporter Types 1 (Glut-1) and 3 (Glut-3) and hexokinase-II (HK-II) in excised lymphoma tissues.MethodsSixteen B-cell non-Hodgkin's lymphoma patients (11 DLBCL and 5 non-DLBCL patients) were included in the study because the lymphoma tissues obtained by excision were eligible for immunostaining. The expressions of Glut-1, Glut-3 and HK-II were assessed regarding the percentages of positively stained lymphoma cells (%expression), the staining intensities (none=0, weak=1, moderate=2 and strong=3) and the staining patterns (membranous or cytoplasmic) and compared between DLBCL and non-DLBCL.ResultsGlut-1 was not expressed at all in DLBCL or non-DLBCL, and their Glut-3 expressions were not significantly different (P>.05) with respect to %expression (mean±S.E.M., 73.6±7.3% vs. 72.0±3.7%), staining intensity (2.5±0.2 vs. 2.6±0.2) and staining pattern (membranous pattern dominant; 54.5% vs. 60.0%). However, DLBCL expressed more HK-II than non-DLBCL, i.e., %expression (45.2±11.5% vs. 17.0±15.8%, P=.0275) and staining intensity (2.3±0.2 vs. 0.6±0.4, P=.0032). HK-II showed a cytoplasmic location in DLBCL and non-DLBCL.ConclusionsHK-II and Glut-3 contribute significantly to FDG uptake in DLBCL. DLBCL may have higher FDG uptake because it expresses more HK-II, whereas Glut-1 appears to play no role in FDG uptake in B-cell non-Hodgkin's lymphoma.