Objective:To discuss the role of RHAMM(receptor for hyaluronan-mediated motility)in invasion and metastasis of cholangiocarcinoma.Methods:Clinical specimens of normal bile duct and cholangiocarcinoma in patients were collected.The specimens of bile duct adenocarcinoma were divided into high

medium and poorly differentiated groups according to the degree of differentiation.All the tissue specimens were divided into three groups according to the TNM staging system.The expressions of RHAMM mRNA and protein level were assayed by RT-PCR and Western blot.Results:There were different expression levels in different histological types of cholangiocarcinoma assayed by immunohistochemistry(P>0.05).Cholangiocarcinoma group and cholangiocarcinoma with metastasis group had positive expression of RHAMM with brown staining in the cytoplasm or membrane.The expression level of RHAMM was the lowest in the control group(0.033 ± 0.003)

while increased in the cholangiocacinoma group(0.162±0.013)

and there was no significant difference between the two groups(P>0.05).The cholangiocarcinoma with metastasis group hold significantly higher expression than the other two groups

and the difference had statistical significance(P<0.05).Conclusion:There is no relation between the degree of differentiation and the expression levels of RHAMM.However

its high expression in the cholangiocarcinoma with metastasis group may be associated with the invasion of cholangiocarcinoma

and promote the metastasis of cholangiocarcinoma ultimately.