PTEN及bcl-2和p53蛋白表达与乳腺癌预后的关系

Prognostic value of PTEN, bcl-2 and p53 protein expression in breast carcinomas

目的 :探讨新的抑癌基因PTEN在人乳腺癌组织中的表达、与bcl 2、p5 3的相关性及其与乳腺癌临床病理学特征和预后的关系。方法 :采用免疫组化SP法检测62例浸润性乳腺癌 (包括浸润性导管癌、浸润性小叶癌、髓样癌等 )标本中PTEN、bcl 2及p5 3蛋白的表达。结果 :62例乳腺癌标本中PTEN、bcl 2及p5 3阳性表达率分别为 64 5 % ( 4 0 /62 )、5 6 5 % ( 3 5 /62 )及2 7 4% ( 17/62 ) ;PTEN与bcl 2之间不具有相关性 ,P >0 0 5 ;PTEN与p5 3之间显著相关 ,P <0 0 1。乳腺癌PTEN蛋白表达水平与患者年龄、肿瘤组织学类型、肿瘤大小之间差异无统计学意义 ,P >0 0 5 ;与肿瘤细胞学分级、淋巴结有无转移及预后之间差异有统计学意义 ,P <0 0 5 ;PTEN低表达患者肿瘤细胞学分级高、淋巴结转移阳性率高、5年生存率低。结论 :1)抑癌基因PTEN在乳腺癌中确实存在突变或缺失。其表达水平的高低作为判断乳腺肿瘤细胞增殖活性、侵袭力及转移的重要指标。 2 )PTEN与bcl 2协同表达与预后相关 ,可作为乳腺癌预后评估的有效指标。 3 )PTEN突变或缺失可能与p5 3存在一定的相关性 ,但其作用机制有待进一步研究。

OBJECTIVE:To investigate the expression of a new tumor suppressor gene PTEN in primary breast carcinoma and its relation with expressions of bcl-2 and p53, clinicopathology and prognosis. METHODS:Immunostaining for PTEN, bcl-2 and p53 protein was performed on 62 paraffin-embedded specimens of primary breast cancer patients diagnosed and treated in our hospital from 1993 to 1996.RESULTS:The positive rates of expressions of PTEN, bcl-2 and p53 protein were 64.5%,56.5% and 27.4% in 62 patients with primary breast carcinoma, respectively. PTEN protein expression level in primary breast carcinoma was closely related to the histologic grade and lymphatic metastasis (P<0.01) and prognosis (P<0.05); there was no statistically significance to tumor size, age and pathological type,P>0.05. The expression of PTEN protein had no correlation with that of bcl-2 protein, P>0.05, but the concurrence analysis of PTEN and bcl-2 had close relation with prognosis, P<0.01. In addition, a significant difference was observed between the expressions of PTEN and p53.CONCLUSIONS: 1)This study suggests that there is mutation and loss of tumor suppressor gene PTEN in primary breast carcinoma and the mutation and loss is related to the histologic grade and lymphatic metastasis, so it could be contributed to reflect proliferating activity and aggression of the disease. 2)From this experiment, we have not found there is relation between PTEN and bcl-2 protein, but the concurrence analysis of PTEN and bcl-2 protein can help to judge the prognosis of patients with breast carcinoma. 3)The expression of PTEN may be closely related to the expression of p53 ( P< 0.05), the mechanism need to be further studied.