Abstract: Abstract :Objective To study the expression of Angiopoietin-2(Ang-2)protein in colorectal carcinoma and evaluate the relationship between Ang-2 protein level and pathology and clinical features. Methods Expression of Ang-2 was examined in 54 patients with colorectal carcinoma and 18 patients with adjacent normal tissues and 20 patients with normal tissues with immunohistochemical technique. Results The positive rate were 77.78%、27.78%和30.00%；Compared the expressions of Ang-2 in colorectal carcinoma tissue with adjacent normal tissue and benign colorectal lesion tissue, there were all significant differences (??=14.890,14.618,P<0.05); The positive expression rates of Ang-2 were significantly correlated with depth of invasion, lymph node metastasis, distant metastasis and clinical stage (r=0.490,0.337,0.338,0.386, P<0.05) in carcinoma patients;With sex,age,nationality,occupation,history of benign desease and family history of cancer,tumor location ,size and degree of differentiation were not related(P>0.05). Conclusion Expression of Ang-2 protein in colorectal cancer may occur in the development ,invasion and metastasis play an important role.

Key words: colorectal carcinoma, Angiopoietin-2, immunohistochemical technique