锰超氧化物歧化酶在乳腺浸润性导管癌中的表达及临床意义

Manganese superoxide dismutase expression and clinical significance in breast invasive ductal carcinoma

目的检测锰超氧化物歧化酶(manganese superoxide dismutase,MnSOD)在乳腺浸润性导管癌组织及癌旁正常组织中的表达,探讨MnSOD在肿瘤的发生及肿瘤侵袭过程中的作用。方法采用RT-PCR和Western blot法分别对20例乳腺浸润性导管癌组织样本和20例癌旁正常组织样本的MnSOD mRNA及蛋白表达进行检测,以β-actin作为定量参考物,比较其在乳腺癌组织和癌旁正常组织中的表达差异,并结合临床特征淋巴结转移和TNM分期,分析MnSOD在肿瘤不同阶段表达的差异。结果乳腺浸润性导管癌组织MnSOD mRNA的表达值为0.61±0.15,癌旁组织为1.24±0.14,两者比较差异具有统计学意义(P<0.01);MnSOD蛋白在癌组织中表达值为0.40±0.04,癌旁组织为0.75±0.06,两者比较差异具有统计学意义(P<0.01)。乳腺浸润性导管癌中淋巴结转移与非淋巴结转移MnSOD mRNA及蛋白表达无统计学意义(P>0.05)。TNM分期:Ⅰ期4例MnSOD mRNA表达值为0.45±0.15,Ⅱ期9例MnSOD mRNA表达值为0.44±0.15,Ⅲ期7例MnSOD mRNA表达值为0.36±0.07,Ⅱ期与Ⅲ期及Ⅰ期与Ⅲ期的比较差异均有统计学意义(P<0.05);Ⅰ期与Ⅱ期比较差异无统计学意义(P>0.05);Ⅰ～Ⅲ期MnSOD蛋白表达三者相互间比较差异均无统计学意义(P>0.05)。结论乳腺浸润性导管癌组织中Mn-SOD mRNA和蛋白表达明显下降,检测MnSOD的表达可作为临床诊治及判定乳腺浸润性导管癌预后的指标。

Purposes To determine the MnSOD expression in infiltrating ductal breast cancer tissue and adjacent normal tissue, and to explore the role of MnSOD in the process of tumorigenesis and invasion, combined with analyses of the clinical characteristics. Meth- ods Twenty cases of infiltrating ductal breast cancer tissue samples and 20 cases of adjacent normal tissue were involved in this study. MnSOD mRNA and protein expression was detected by RT-PCR and Western blotting, conserved gene β-actin used as a quantitative reference, combined with the analyses of clinical features, lymph node metastasis and TNM staging. Results MnSOD mRNA expres- sion in breast invasive ductal carcinoma tissue was decreased （0. 61 ±0. 15）, as compared with that in adjacent noncancerous tissues （ 1.24 ± 0.14）, with statistically significant differences （P 〈 0. 01 ）, MnSOD protein expression in cancerous tissues was lower （0.40 ± 0. 04） as compared with that in adjacent tissues （0.75 ± 0.06） （ P 〈 0, 01 ）. Compared lymph node metastasis in breast invasive ductal carcinoma with non-lymph node metastasis, MnSOD mRNA and protein expression had no significant difference （ P 〉 0. 05）. In TNM staging, MnSOD mRNA expression in stage I （4 cases） was 0. 45 ±0. 15, 0. 44 ±0. 15, in stage II （9 cases） and 0. 36 ±0. 07 in stage III （7 cases）. There was a significant difference between cancers in stage I and stage III and between stage II and stage III （P 〈 0. 05 ）, but no significant difference between stage I and II （P 〉 0. 05 ）, among cancer patients in stages I , II and m, Mn- SOD protein expression was no significant difference （P 〉 0. 05 ）. Conclusion MnSOD mRNA and protein expression is significantly decreased in breast invasive ductal carcinoma. The detection of MnSOD expression can be used in the clinical diagnosis, treatment and prognosis evaluation of infiltrating ductal cancer of the breast.