대한대장항문학회

The primary metabolic characteristic of malignant cells is an increased uptake of glucose<br>and its anaerobic glycolysis. Recent studies have demonstrated that facilitative glucose<br>transport across the plasma membrane is mediated by a family of proteins, i.e., glucose<br>transporters.<br>Purpose: In order to evaluate the clinicopathologic correlations of glucose transporter genes<br>expressed in colorectal cancer, the author studied the expression of glucose transporter genes<br>in human colorectal cancer and analyzed their expression in normal and malignant colorectal<br>tissues.<br>Methods: A reverse transcriptase-polymerase chain reaction (RT-PCR) was applied to<br>quantitatively determine the levels of the glucose transporter genes, GLUT1 and GLUT3, from<br>Crohn's diseases (N=2), adenomatous polyps (N=4), and colorectal cancers (N=40) and their<br>normal counterparts.<br>Results: The expresssion of the GLUT1 gene was detected in 50% of the inflammatory<br>colonic mucosae and adenomatous polyp tissues, but the levels of expression were not<br>significantly different from their normal counterparts. Among the 40 colorectal cancer patients,<br>23 patients (57.5%) showed GLUT1 gene expression and the levels of expression were<br>increaed by 1.8 as compared to their normal counterparts (p＜0.05). The expression of the<br>GLUT3 gene was detected in almost all tissues examined, and the levels of expression were<br>not significantly different from their normal counterparts. In colorectal cancers, there was<br>correlation between GLUT1 expression, the extent of lymph node involvement and the stage<br>of colorectal cancers (p＜0.05). But, the correlation between the expressions of the GLUT3<br>gene and the clinicopathologic prognostic factors of colorectal cancers could not be determined<br>because almost all tissues showed a GLUT3 gene expression.<br>Conclusions: In conclusion, the GLUT1 glucose transporter expression in colorectal cancer<br>was associated with high possibilities of lymph node metastases and poorer prognosis, and<br>the assessment of GLUT1 expression in colorectal cancer would be useful in identifying high<br>risk patients.<br>