Objective To identify the expression of pleiotrophin （PTN） mRNA and protein in the colorectal cancer tissues， and to explore the clinical value of it. Methods The expressions of PTN mRNA and protein in colorectal cancer tissues （colorectal cancer group） as well as normal colorectal tissues （normal control group） were tested by using in-situ hybridization and immunohistochemistry. Results The positive rates of PTN mRNA 〔63.9% （53/83） vs. 40.7%（22/54）〕 and protein〔60.2%（50/83） vs. 33.3%（18/54）〕 in colorectal cancer group were all significantly higher than those of normal control group （P=0.008， P=0.002）. There were no significant relationship between expressions of PTN mRNA and protein with gender， age， and type of tumor （P＞0.05）， but in tissues of Ⅲ-Ⅳ stage and poor differentiation，the positive rates of PTN mRNA and protein were all higher （P＜0.05）. Conclusions The over expressions of PTN mRNA and protein in colorectal cancer tissues may directly related to the invasion and metastasis. Meanwhile， it can be used as an index to predict metastasis and prognosis of colorectal cancer.
