Immunohistochemical expression of the glucose transporters Glut-1 and Glut-3 in human malignant melanomas and benign melanocytic lesions

Paola Parente,Giulio Bigotti,Manuela M Fabrizi,Antonella Mangoni,Guido Massi,Antonella Coli

doi:10.1186/1756-9966-27-34

Abstract

BackgroundReported data indicate that cancer cells have increased rates of glucose metabolism, as determined by 18FDG-PET imaging in patients with malignancies. The results of many studies have demonstrated that the expression of glucose transporters, especially Glut-1, is increased in a variety of malignancies. This study was undertaken to assess the differential expression of Glut-1 and Glut-3 by benign and malignant melanocytic lesions.MethodsImmunohistochemical staining for Glut-1 and Glut-3 was performed on paraffin-embedded tissue sections prepared from melanocytic nevi (12 cases), Spitz nevi (12 cases) and primary cutaneous malignant melanomas (20 cases).ResultsWe observed immunoreactivity for Glut-1 in all melanocytic nevi, 9 of the 12 Spitz nevi and in 9 of the 20 malignant melanomas, whereas Glut-3 was expressed in all the melanocytic lesions, both benign and malignant.ConclusionThese findings indicate that the glucose transporters Glut-1 and Glut-3 play a role in the glucose metabolism of melanocytic cells. Glut-1 was present in the majority of benign nevi, whereas its expression was downregulated in 55% of malignant melanomas. Our results suggest that glucose transporter Glut-1 expression can significantly discriminate between human malignant melanoma and benign melanocytic nevi, and support the idea that additional mechanisms other than Glut-1 may contribute to glucose uptake in melanomas.

Highlights

Reported data indicate that cancer cells have increased rates of glucose metabolism, as determined by 18FDG-PET imaging in patients with malignancies
Glut-1, whose expression can be induced in cancer cells by oncogenes, growth factors, interleukin-1, local hypoxia and inflammatory changes, enhances the activity of the matrix metalloproteinases, whose activities have been directly related to tumour invasiveness and metastasis [2,6,9,19]
Immunoreactivity of Glut-1 was detected in 100% of the melanocytic nevi, in 75% of the Spitz nevi and in 45% of the melanomas, whereas Glut-3 was expressed in all the melanocytic lesions, both benign and malignant

Summary

Introduction

Reported data indicate that cancer cells have increased rates of glucose metabolism, as determined by 18FDG-PET imaging in patients with malignancies. The results of many studies have demonstrated that the expression of glucose transporters, especially Glut-1, is increased in a variety of malignancies. Glut-1 was the first member of the facilitated glucose transporter family identified [1] It is mostly expressed in erythrocytes, endothelial cells of the blood-brain barrier and placental cells [3]. The human Glut-1 gene, which has been localized to the short arm of chromosome 1 (1p34.2), is 35 kb in length and contains 10 exons that encode a protein of 492 aminoacids. This (page number not for citation purposes)

Methods

Results

Discussion

Conclusion