摘要
Objective： The aim of the study was to explore the role of Wnt βcatenin signalling pathway in the maintenance, invasion and metastasis of colorectal cancer stem cells. Methods： Double immunohistochemical staining was used to detect the expression of EpCAMhigh/CD44~ which is regarded as the marker of colorectal cancer stem cells in 80 cases of colorectal cancer and their corresponding liver metastases. The SP method of immunohistochemistry was used to detect the expression of the key protein βcatenin in the Wnt pathway in these tissue. The expression and correlation of ^-catenin and EpCAMh^gh/ CD44＋ in colorectal cancer were analyzed and their role on the biological behavior of colorectal cancer was explored. Results： The abnormal expression of βcatenin was significantly higher in colorectal cancer than in the paraneoplastic normal intes- tinal mucosa [55% （44/80） vs 10% （2/20）, P 〈 0.05]. The positive expression of EpCAMhigh/CD44＋ was significantly higher in colorectal cancer than in the paraneoplastic normal intestinal mucosa [66.25% （53/80） vs 0% （0/20）, P 〈 0.05]. In the 80 cases of colorectal cancer, the abnormal expression of ^-catenin has no correlation with gender （P = 0.079）, age （P = 0.416） and the magnitude （P = 0.816） of the tumor （P 〉 0.05）, but it was significantly correlated with degree of differentiation （P = 0.001）, depth of invasion （P = 0.001）, clinical stage （P = 0.000） and metastasis （P = 0.000）. In the colorectal cancer, the expression of EpCAMhi^h/CD44~ cells has no correlation with gender （P = 0.934） and the magnitude （P = 0.160） of the tumor （P 〉 0.05）, but was significantly correlated with age （P = 0.021）, degree of differentiation （P = 0.013）, depth of invasion （P = 0.000）, clinical stage （P = 0.000） and metastasis （P = 0.000）. In the corresponding liver metastases, we could also detecte EpCAMhih/CD44＋ cells. In cases with abnormal expression of βcatenin, the positive expression rate of EpCAMhigh/CD44＋ was significantly higher than those with normal expression of β-catenin （84.1% vs 44.4%）, and the difference was statistically significant （P 〈 0.05）. Conclusion： The abnormal activation of Wnt β-catenin signalling pathway may prompt the abnormal proliferation of the colorectal cancer stem cells, which leads to the recurrence and metastasis of the cancer.
