Clinicopathologic significance of GLUT1 expression and its correlation with Apaf-1 in colorectal adenocarcinomas

AIM: To investigate the role of glucose transporter 1 (GLUT1) expression in colorectal carcinogenesis and evaluate the correlation with clinicopathological parameters and apoptosis-activating factor-1 (Apaf-1) expression in colorectal adenocarcinomas. METHODS: We used tissue microarrays consisting of 26 normal mucosa, 50 adenomas, 515 adenocarcinomas, and 127 metastatic lesions. Medical records were reviewed and clinicopathological analysis was performed. RESULTS: GLUT1 expression was absent in normal mucosa and low or moderately apparent in 19 cases (38.0%) of 50 adenomas. However, GLUT1 expression was detected in 423 (82.1%) of 515 adenocarcinomas and in 96 (75.6%) of 127 metastatic lesions. GLUT1 expression was significantly correlated with female gender (P = 0.009), non-mucinous tumor type (P = 0.045), poorer differentiation (P = 0.001), lymph node metastasis (P < 0.001), higher AJCC and Dukes stage (P < 0.001 and P < 0.001, respectively). There was a significant inverse correlation between GLUT1 expression and Apaf-1 expression (P = 0.001). In univariate survival analysis, patients with GLUT1 expression demonstrated poor overall survival and disease-free survival (P = 0.047 and P = 0.021, respectively, log-rank test). CONCLUSION: GLUT1 expression was frequently increased in adenocarcinomas and metastatic lesions. GLUT1 expression was significantly correlated with poorer clinicopathologic phenotypes and survival of patients with colorectal adenocarcinomas. (C) 2011 Baishideng. All rights reserved.