J Nucl Med 2001 Oct;42(10):1551-5
FDG uptake and glucose transporter subtype expressions in experimental tumor
and inflammation models.
Mochizuki T, Tsukamoto E, Kuge Y, Kanegae K, Zhao S, Hikosaka K, Hosokawa M,
Kohanawa M, Tamaki N.
Although FDG uptake is closely related to the expression of the glucose
transporter (GLUT) in malignant tumors, such a relationship has not been fully
investigated in inflammatory lesions. The aim of our study was to determine the
expression of GLUT subtypes in experimental inflammatory lesions and to compare
the results with those in malignant tumors in relation to FDG accumulation.
METHODS: Rats were inoculated with a suspension of Staphylococcus aureus or
allogenic hepatoma cells (KDH-8) into the left calf muscle. Five days after S.
aureus inoculation (n = 9) and 14 d after KDH-8 inoculation (n = 11), [(14)C]FDG
was injected intravenously and its accumulation in the infectious and tumor
tissues was determined as the percentage activity of the injected dose per gram
of tissue (%ID/g). The expression of glucose transporters (GLUT-1 to GLUT-5) was
investigated by immunostaining the infectious tissues (n = 6) and the tumor
tissues (n = 6). Immunohistochemical grading was assessed semiquantitatively by
5 observers. RESULTS: The [(14)C]FDG uptake was significantly higher in the
tumor lesion than in the inflammatory lesion (2.04 +/- 0.38 %ID/g vs. 0.72 +/-
0.15 %ID/g; P < 0.0001). The tumor and inflammatory tissues highly expressed
GLUT-1 and GLUT-3. The GLUT-1 expression level was significantly higher in the
tumor tissue than in the inflammatory tissue (P < 0.05). CONCLUSION: The
results based on our models showed a high FDG uptake and high GLUT-1 expression
level not only in the tumor lesion but also in the inflammatory lesion. The
higher GLUT-1 expression level in the tumor lesion may partially explain the
higher FDG accumulation in the tumor than in the inflammatory lesion.
