Background and objective: It has been known that the expression levels of ERCC1 and GST-pi were correlated with tumorigenesis and prognosis. The aim of this study is to investigate the relationship between expression levels of ERCC1 and GST-pi, and clinicopathologic parameters and survival in patients with lung cancer.
Methods: The expression levels of ERCC1 and GST-pi were detected by immunohistochemical staining on tissue micro-array sections made of 148 cases of lung cancer and 7 cases of normal lung samples. The results were compared with relevant clinical and pathologic data.
Results: Positive rates of ERCC1 and GST-pi were 36.2% and 73.6%, respectively. None of normal lung samples was positive staining. Positive expression of ERCC1 was significantly higher in group of non-small cell lung cancer (NSCLC), highly differentiated and the smokers less than 400 (P < 0.05), positive expression of GST-pi was significantly higher in group of non-smokers and NSCLC (P < 0.05). There were significant correlations between expression of ERCC1 and GST-pi (r = 0.253, P = 0.001). The 5 years survival rate was higher in positive expression of ERCC1. There was significant correlations between expression of ERCC1 and survival (P = 0.037). There was no significant correlations between expression of GST-pi and survival (P = 0.614). Multivariate analysis using Cox regression model showed that expression levels of ERCC1 and GST-pi were not the important independent prognostic factors for survival.
Conclusion: ERCC1 and GST-pi are aberrant highly expressed in NSCLC with positive correlation, which indicate they might act synergistically in tumorigenesis of NSCLC. The positive expression of ERCC1 have better survival and may have effect on prognosis.
背景与目的: 切除修复交叉互补基因1（excision repair cross complementing 1, ERCC1）和谷胱甘肽S-转移酶-Pi（glutathione S-transferase Pi, GST-pi）与肿瘤的发生与预后密切相关。本研究探讨ERCC1和GST-pi在肺癌中的表达与临床病理特征和预后的意义。
方法: 选取148例肺癌标本，与7例正常肺组织标本一起制成组织芯片，应用免疫组化S-P法检测ERCC1和GST-pi的表达，并与临床病理特征及预后进行比较分析。
结果: ERCC1和GST-pi在肺癌标本中的阳性表达率分别为36.2%和73.6%，ERCC1和GST-pi在正常肺组织标本中均无表达，ERCC1阳性表达在非小细胞肺癌（non-small cell lung cancer, NSCLC）、分化程度为中高分化和吸烟指数 < 400的患者中明显升高（P值均 < 0.05），GST-pi阳性表达在无吸烟者及非小细胞肺癌患者中明显升高（P值均 < 0.05）。ERCC1和GST-pi的表达呈正相关（r=0.253, P=0.001）。Kaplan-Meier生存分析显示，ERCC1阳性表达者5年总生存率优于阴性表达者，ERCC1的表达与生存显著相关（P=0.037），GST-pi的表达与生存无显著相关（P=0.614）。Cox多因素分析结果显示，NSCLC患者中肿瘤大小（P=0.028, 95%CI: 1.087-4.378, RR=2.181）和临床分期（P=0.019, 95%CI: 1.076-2.279, RR=1.566）是影响预后的独立危险因素；ERCC1和GST-pi的表达不是影响预后的独立因素。
结论: ERCC1和GST-pi在非小细胞肺癌中表达升高并且存在正相关关系，可能在非小细胞肺癌发生发展中起协同作用。ERCC1阳性表达者生存期长，可能在预后判定中有一定作用。