Overexpression of GLUT1 in Colorectal Cancer is Independently Associated with Poor Prognosis

Abstract

To investigate the expression of glucose transporter 1 (GLUT1) in colorectal cancer (CRC) and its relationship to clinicopathological variables. The expression of GLUT1 in 163 primary tumors together with the corresponding normal mucosa, and 36 liver metastases was examined using real-time PCR. The mean value of GLUT1 was higher in primary tumors (50.390 ± 68.648) than in the corresponding normal mucosa (20.437 ± 28.703, p<0.0001), while there was no significant difference in GLUT1 expression between CRC and liver metastasis (50.390 ± 68.648 vs 52.277 ± 52.482, p=0.190). In CRCs, GLUT1 expression was higher in poorly differentiated than in well and moderately differentiated tumors (p=0.022), and higher in stage III + IV than in stage I + II tumors (p=0.035). The patients with high-expressed GLUT1 had a worse prognosis than those with low-expressed GLUT1 independently of gender, age, tumor site, stage and differentiation (p=0.026, RR 2.737, 95% CI 1.126-6.651) in stage I-III CRCs. In liver metastasis, GLUT1 expression was higher in larger tumors than in smaller ones (p=0.025). Overexpression of GLUT1 in stage I-III CRCs was independently associated with poor prognosis.