抑癌基因PTEN在结肠直肠癌中表达的研究

目的：探讨PTEN蛋白在结肠直肠癌组织中的表达及其临床意义。方法：应用免疫组织化学技术检测1998年1月至1999年8月间于我院收治的122例结肠直肠癌组织标本中frrEN蛋白的表达。结果：在122例结肠直肠癌组织标本中有39例为阴性表达，正常结肠直肠黏膜组织、腺瘤组织均为阳性表达（P〈0．01）。无论阳性面积抑或强阳性面积，PTEN蛋白表达与结肠直肠癌病人的性别、年龄无显著相关性（P〉0．05）；而与结肠直肠癌周径、淋巴结转移、远处转移、肿瘤分化程度和Dukes分期存在显著相关（P〈0．01）。肿瘤分化各组两两比较显示，在阳性面积中除高分化与中分化腺癌、在强阳性面积中除低分化与未分化腺癌（P〉0．05）外，其余各组间统计学检验均存在显著性差异（P〈0．01）。Dukes分期各期两两比较，无论是阳性面积还是强阳性面积，除B期与C期（P〉0．05）外，其余各组间统计学检验均存在显著性差异（P〈0．01）。结论：PTEN抑癌基因的蛋白表达低下或丢失与结肠直肠的癌变有关，可能是结肠直肠的癌变过程中一种较晚发生的事件，是进展期结肠直肠癌的一种信号。

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 (P<0.01).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.