PTEN protein expression in colorectal cancer and its clinical significance

Objective To evaluate the expression of PTEN in human colorectal cancer tissue,and to explore its re- lationship with the biological behaviors of the tumor.Methods Immunohistochemieal stain methods were applied with monoclonal antibody against PTEN protein in tissure samples obtained from 122 patients with colorectal carcinomas.The correlation between PTEN expression and the clinicopathologic factors were investigated.Results Reduced PTEN ex- pression progressively increased from normal enteric epithelium to adenocarcinoma (P0.01).The expression of PTEN was correlated to tumor size,cell differentiation,lymph node metastasis,distant metastasis and Dukes' staging,but not to gen- der and age.Conclusions Loss of tumor suppressor PTEN protein expression usually occurs in human colorectal carcino- ma and it might be an advance stage event of colorectal cancer.