BACKGROUND:EpCAMhighCD44+ colon cancer stem cels have been isolated in recent years, and most of them are related to the study of isolating tumor stem cels in colorectal cancer cel lines. There are less reports on the function of colon cancer stem cels. OBJECTIVE:To isolate, screen and culture colon cancer stem cels from colorectal carcinoma tissues and to explore the protein expression and biological characteristics of colon cancer stem cels. METHODS: The primary cels were isolated from the colon cancer tissues. EpCAMhighCD44+ cels were detected and sorted by flow cytometry. Then, these cels were cultured in serum-free medium. After the cels were replanted subcutaneously into the mice, we observed the daily performance and tumor growth in the mice. When the tumor diameter was above 1 cm, tumor tissues were taken for immunohistochemical testing. The growth of EpCAMhighCD44+ cels cultured in the serum-free medium was observed; expressions of neutral epithelial mucin and CK-20 in EpCAMhighCD44+ cels were detected. RESULTS AND CONCLUSION: EpCAMhighCD44+ colon cancer stem cels were detected in the colon cancer tissues, and the proportion of EpCAMhighCD44+ cels in primary colon cancer cels was 1.7%-38%. After 24 hours of serum-free culture, there were a few of smal suspended cel spheres which were incompact. After 21 days, dense cel spheres with uniform size were found. The formation of transplanted tumor was found in the nude mice. Hematoxylin-eosin staining showed the transplanted tumor had the typical characteristics of colon cancer cels. The expression of neutral epithelial mucin and CK-20 was observed in al the transplanted tumors. Additionaly, the proliferation of EpCAMhighCD44+ cels could be promoted by 5-fluorouracil (10, 1, and 0.1 PPC) with time. These findings indicate that EpCAMhighCD44+ colon cancer stem cels in the colon cancer have a certain ability of proliferation, regeneration, differentiation, tumor formation and chemotherapy resistance.

Objective To investigate the potential risk factors for the death of patients with colorectal cancer during perioperative periods.Methods The clinical data of 545 patients with colorectal cancer were analyzed retrospectively.17 factors,which may influence mortality of patients with colorectal cancer during perioperative periods were evaluated.These enumeration data were analyzed with x2 test,then those factors with obvious difference in statistics were further analyzed by multi-factor Logistic regression analysis.The independent risk factors affecting the mortality of patients with colorectal cancer during perioperative periods were obtained from the analysis.Results There were 6 independent risk factors derived that had significant impacts on perioperative death that were postoperative complications,operation method,non-planed reoperation,preoperative electrolyte disturbance,preoperative hypoalbuminemia,and age(P ＜ 0.05).Conclusions Many potential factors could affect perioperative mortality of patients with colorectal cancer undergoing surgical procedure.

Objective To explore the risk factors of liver metastasis from colorectal cancer. Methods The clinic data of 1341 patients with colorectal cancer who had been admitted to our department from January 1989 to December 2004 were analyzed retrospectively. Results The incidence of the liver metastasis from colorectal cancer was 11.56% (155/1341). Univariate analysis showed that sex, location and size of the primary tumor site, regional lymph node metastasis, infiltration depth of the bowel wall, involvement of the adjacent viscera, complications and peritoneal implantation were relevant to liver metastasis (X2=6.517, 10.208, 11.173, 42.160, 80.731,6.593, 3.887, 14.352, P < 0.05). Logistic regression analysis showed that sex, regional lymph node metastasis, infiltration depth of the bowel wall, complications and primary tumor site were correlated with liver metastasis ( b = 0.655, -0.488, 1.355, -0.752, 0.273, P <0.05). Conclusions Male patients, patients with regional lymph node metastasis or with involvement of tissues out of the serosa have higher chance of liver metastasis from coloreetal cancer. Patients with colon cancer are apt to develop liver metastasis than those with rectal cancer. The incidence of liver metastasis in colorectal cancer patients complicated with other diseases is low.