Objective: To observe the inhibitory effect of Changweiqing on liver metastasis of colorectal cancer in mice

and investigate the related mechanism of Changweiqing on liver metastases of colorectal cancer

by Chemokine Ligand 12 (CXCL12)/Chemokine Receptor 4 (CXCR4)the signal transduction pathway and the expression of Matrix metalloproteinase 9(MMP9). Method: We established the liver metastases model of mice with implanted colon cancer CT26.Mice were divided into four groups

namely sham operation group

model group

the low dose group and the high dose group of Changweiqing. Sham operation group and model group were given normal saline

Changweiqing low and high dose groups were administrated with 10.37

20.74 g·kg-1 respectively. The HE staining was performed to judge liver metastasis. The expression of the CXCR4

CXCL12

and MMP9 was detected by immunohistochemistry and quantitative real-time PCR in the colorectal tumor tissues and the normal colon tissue. Result: The weight inhibition rates of colon in situ tumor in Changweiqing low and high dose groups were 24.73%

45.91%; while the volume inhibition rates were 27.93%

63.48%. The liver metastasis rates were 75%

37.5%

12.5% in the model group

Changweiqing low and high dose groups respectively. The CXCR4

CXCL12

MMP9 protein and mRNA expression of the colon tumor tissue in model group were significantly higher than that in the sham operation group (P<0.05)

while the low and high dose Changweiqing could reduce their expressions (P<0.05). CXCR4 protein and mRNA expression in Changweiqing low dose and high dose groups showed significant decrease compared with those in model group (P<0.05). CXCL12

protein expression in Changweiqing low dose and high dose groups was significantly decreased compared with that in the model group (P<0.05). CXCL12 mRNA in Changweiqng high dose group was significantly decreased compared with that in the model group (P<0.05). For MMP9 protein and mRNA expression

Changweiqing high dose could decrease them significantly compared with those in the model group (P<0.05). Conclusion: Changweiqing inhibits the colorectal cancer tumor growth in situ and the incidence of liver metastasis in mice

The mechanism is likely related to the down-regulation of CXCR4

CXCL12

MMP9 expression in the tumor tissue.