Abstract: ObjectiveTo explore the expression and clinical significance of smoothened (Smo) and Gli-1 protein in human endometrial carcinoma tissues. MethodsThe levels of Smo and Gli-1 were examined in human endometrial tissues (15 samples), atypical hyperplasia tissues (15 samples) and endometrial carcinoma tissues (50 samples) by immunohistochemistry. ResultsThe levels of Smo and Gli-1 were not detected or weakly expressed in normal endometrium, but increased in atypical hyperplasia tissues and over-expressed in endometrial carcinoma. The differences between the groups were statistically significant (P<0.05). According to correlation analysis, the expression of Smo and Gli-1 was positively correlated in endometrial carcinoma tissues samples (r=0.624,P<0.05). ConclusionsThe abnormal activation of Smo and Gli-1 is closely associated with the pathogenesis of endometrial carcinoma, which may be related with the up-regulated expression of Gli-1 by Smo protein.