Establishment Of Colorectal Cancer Liver Metastasis Animal Models

Background and Objective:Colorectal cancer is a common tumor of highly incidence,liver metastases is a key factor impact prognosis of colorectal cancer patients.Compare several establishing methods of animal models,analyze each model's character,define a suitable method of establishing animal model of colorectal cancer with liver metastasis to probe the prevention and treatment of colorectal cancer with liver metastases.Methods:BALB/c mice group randomly into 11 groups.The mice were injected different doses(0.1ml,0.2ml,0.3ml,1.0ml, concentration 1 x 106/ml) of CT26(colon adenocarcinoma cells of mice in indexing growth) by spleen,rectum,peritoneal trail(no 1.0ml dose group in peritoneal group ).According to the results of randomized experiments,add 40 and 20 mice to 0.2 dose group of spleen and rectum group.The survival time of mice after inoculation and the tumors' growth and liver metastases in mice after natural death was observed,Liver of the mice was calculated for pathological examination,calculate the incidence of liver metastasis.The result including the liver metastasis rate and the survival time were analyzed and compared differences in-group using spssl3.0,and the liver metastasis rate was compared differences between groups using spssl3.0. 1.Liver metastasis rate:(1) Spleen group:the liver metastasis rate in 0.1 ml,0.2ml,0.3ml,1.0ml doses group through spleen group were 50.0%,77.2%,50.0%,27.0%.(2) Rectum group:the liver metastasis rate in 0.1ml,0.2ml,0.3ml,1.0ml doses group through rectum group were 50.0%,53.1%,16.7%,6.7%.(3) Peritoneal group:the liver metastasis rate in 0.1ml,0.2ml,0.3ml doses group through peritoneal were 10.0%,22.2%,10.0%.2.Liver metastasis rates were compared in-group:(1) Spleen group: 0.2ml dose has significant difference from 0.1ml and 0.3ml dose(X~2= 5.226,P=0.022).The other doses have no significant differences compared between 2 doses.(2) Rectum group:0.1ml dose was significant difference from 0.3ml dose(X~2=4.677,P=0.031),0.1ml dose has significant difference from 1.0ml dose(X~2=7.468,P=0.006),0.2ml dose has significant difference from 0.3ml dose(X~2=6.380,P=0.012),0.2ml dose has significant difference from 1.0ml dose(X~2=9.328,P=0.002). 0.1ml dose compared with 0.2ml dose,0.3ml dose compared with 1.0ml dose,show no significant differences between 2 doses.(3) Peritoneal group:there was no significant difference compared between 2 doses.3.Liver metastasis rate compared between spleen group and rectum group:0.2ml dose inject by spleen group has statistically significant difference from 0.1ml dose and 0.2ml dose inject by rectum group(X~2 =7.700,P=0.021).Inject through spleen with a dose of 0.2ml(l×10~6/ml) CT26 is a higher way to establish animal model of colorectal cancer with liver metastasis.Inject through rectal with a dose of 0.1ml or 0.2ml(l×10~6/ml) CT26 is a simple way of establish animal model of colorectal cancer with liver metastasis,and also a way follow the law of liver metastases of colorectal cancer.