Objective:Transcription factor Snail can restrain the expression of E-cad

which results in epithelial-mesenchymal transition

thereby promoting invasion and metastasis of cancers.This study aimed to investigate the role and significance of EMT regulated by Snail in colorectal cancer of invasion and metastasis

through detecting the expression of Snail and E-cad in colorectal cancer

adjacent tissues and colorectal cancer cells SW480.Methods:Immunohistochemical detection the Snail

E-cad expression of 40 cases of colorectal cancer and adjacent tissues and to analyze their correlation;siRNA interference Snail gene of colorectal cancer cells SW480 which were divided into control group

empty plasmid group and transfection group

RT-PCR were used to detect Snail

E-cad mRNA expression in each group;Transwell chamber invasion assay and heterogeneous matrix adhesion experiments were used to detect the invasion of colorectal cancer cell in each group and the heterogeneity of adhesion ability.Results:The positive rate of Snail and E-cad were 57.5% and 27.5% in colorectal cancer tissues

and 10%

80% in adjacent tissues respectively

with statistically significant between colorectal cancer tissues and adjacent tissues(P<0.05).The expression of these two proteins was related to the differentiation and lymph node metastasis(P<0.05)

but not to patients’age

sex(P >0.05).And the expression of Snail was negatively correlated with E-cad(P <0.05).RT-PCR results showed that compared with the control group

Snail

E-cad mRNA expression in the empty plasmid group was not significant(P>0.05)

while transfection groups was statistically significant(P<0.05);matrix invasion assay and heterogeneous adhesion test results showed that compared with the control group

colorectal cancer cells transfected reduced invasiveness and adhesion heterogeneity

the difference was statistically significance(P<0.05)

while the empty plasmid group was not statistically significant(P>0.05).Conclusion:Snail regulation of EMT was closely related with invasion and metastasis of colorectal cancer

Snail

E-cad can be used as the indicators of invasion and metastasis of colorectal cancer.