Expression of Glucose Transporter 1 (Glut-1) in Cell Lines and Clinical Specimens from Human Prostate Adenocarcinoma

Abstract

Background: Increased uptake and metabolism of glucose is a characteristic of malignant transformation. Overexpression of glucose transporters, especially Glut-1, is a common event in human malignancies. To date, little is known about the role of Glut-1 in human prostate cancer (PC). The aim of this study was to investigate the expression of Glut-1 both in PC cell lines and clinical specimens of primary PC. Materials and Methods: The PC cell lines DU145, PC3 and LNCaP were assessed for Glut-1 mRNA expression by Northern blot analysis. In a total of 45 primary PC specimens, radioactive (³⁵S) in situ hybridizations (RISH) for Glut-1 mRNA expression were performed on frozen sections. Quantification of Glut-1 expression was obtained by use of an image analysis system. Results: Glut-1 expression was detected in all 3 cell lines. Expression in the more poorly-differentiated cell lines DU145 and PC3 was even higher than in the hormone-responsive LNCaP cell line. In situ hybridizations in primary PC revealed Glut-1 expression just above the detection limit in well-differentiated tumors. Significantly increased Glut-1 expression was detected in moderately- to poorly-differentiated PC. Conclusion: Glut-1 is expressed in PC cell lines and primary PC. The level of expression increases with advancing grade of malignancy. These findings support a role for Glut-1 in PC proliferation.