非小细胞肺癌肿瘤微环境中IFN-γ、TGF-β1、IDO表达变化及其相关性

Expression changes of IFN-γ,TGF-β1 and IDO and their correlation in the tumor microenvironment of non-small cell lung cancer

目的:探讨不同分期非小细胞肺癌(non-small cell lung cancer,NSCLC)肿瘤微环境中IFN-γ、TGF-β1和吲哚胺-2,3-双加氧酶(indoleamine-2,3-dioxygenase,IDO)表达的变化及IFN-γ、TGF-β1表达与IDO表达的相关性。方法:选取2013年1月至2015年6月间昆明医科大学第一附属医院胸外科手术切除或纤维支气管镜取得的107例NSCLC患者肿瘤组织(实验组)和19例肺部外伤患者的正常肺组织(对照组)进入研究,实验组按2010年AJCC第七版肺癌分期标准分为4组:1组,Ⅰ期患者28例;2组,Ⅱ期患者26例;3组,Ⅲ期患者28例;4组,Ⅳ期患者25例。ELISA法检测组织中IFN-γ、TGF-β1、IDO蛋白浓度;免疫组化染色检测组织中IDO表达水平;分析IFN-γ、TGF-β1浓度与IDO浓度的相关性,分析肺癌组织中IDO、IFN-γ和TGF-β1表达间的相关性。结果:与对照组相比,Ⅰ期NSCLC组织中IFN-γ的浓度显著升高(P<0.05),而Ⅲ、Ⅳ期组织中IFN-γ浓度显著降低(P<0.05),并且Ⅳ期浓度显著低于Ⅲ期(P<0.05);IDO浓度变化与TGF-β1相似,在Ⅰ期NSCLC肿瘤组织中的浓度与正常肺组织无显著差异(P>0.05),但在Ⅱ、Ⅲ、Ⅳ期肿瘤组织中浓度显著高于正常肺组织(P<0.05),且随分期升高而升高。Pearson相关分析显示,正常组织、Ⅰ期NSCLC肿瘤组织中IDO的浓度与IFN-γ浓度呈正相关(r=0.969,P<0.01;r=0.853,P<0.01),与TGF-β1无相关性。但Ⅱ、Ⅲ、Ⅳ期肿瘤组织中IDO的浓度与TGF-β1浓度呈正相关(r=0.678,P<0.01;r=0.810,P<0.01;r=0.630,P=0.01),与IFN-γ无相关性。结论:早期NSCLC患者免疫微环境中IFN-γ增高,但随着疾病进展,患者免疫力降低,IFN-γ表达减少,IDO、TGF-β1表达增加,早期IDO表达可能与IFN-γ有关,而晚期则可能与TGF-β1有关。

Objective： To investigate the expression changes of IFN-γ,TGF-β1 and indoleamine-2,3-dioxygenase（ IDO） in tumor microenvironment of non-small cell lung cancer（ NSCLC） patients at different clinical stages,as well as the correlation between IDO expression and the expressions of IFN-γ,TGF-β1. Methods： 107 NSCLC tissue samples（ experiment group） were obtained from patients who underwent surgical therapy or bronchoscopy biopsy at the Department of Thoracic Surgery of The 1stAffiliated Hospital of Kunming Medical University From January 2013 to June 2015,and 19 normal lung tissues（ control group） were obtained from lung injury patients. The samples of experiment group were divided into four groups according to the 7th edition of the American Joint Committee on Cancer（ AJCC） tumor-node-metastasis（ TNM） system. Group 1： patients with stage Ⅰ（ 28 patients）,group 2： patients with stage Ⅱ（ 26 patients）,group 3：patients with stage Ⅲ（ 28 patients） and group 4： patients with stage Ⅳ（ 25 patients）. The protein concentrations of IFN-γ,TGF-β1 and IDO were detected by ELISA and the IDO expression in tissues was assessed by immunohistochemistry. At same time,the correlations between IDO expression and IFN-γ,TGF-β1 expression in cancer tissues were evaluated. Results： Compared with control group,the IFN-γ expression in tissues of group 1 was significantly elevated（ P〈0. 05）,while its expressions in group 3 and group 4 were significantly decreased（ P〈0. 05）. Moreover,the IFN-γ expression in tissues of group 4 was significantly less than that of group 3（ P〈0. 05）. Similar to TGF-β1,the IDO expression in group1 was not significantly different with control group（ P〈0. 05）; but the TGF-β1 and IDO expressions in group 2,3 and 4 were higher than those of normal tissues（ P〈0. 05）. Furthermore,The TGF-β1 and IDO expressions increased as the tumor stage went higher. Pearson correlation analysis showed that the IDO expressions in control group and group1 were directly correlate with IFN-γ（ r = 0. 969,P〈0. 01,r = 0. 853,P〉0. 01）,but not correlate with TGF-β1.However,in group 2,3 and 4,the IDO expressions were directly correlate with TGF-β1（ r = 0. 678,P〈0. 01,r =0. 810,P〈0. 01,r = 0. 630,P = 0. 01）,but not correlate with IFN-γ. Conclusion： Expression of IFN-γ in immune microenviroment of NSCLC patients increased at early stage,then with the progress of the disease,the immune function of patients was weakened and the expression of IFN-γ was reduced while the expressions of IDO and TGF-β1 were increased,indicating that IDO expression might be relate to IFN-γ at early stage of NSCLC,and relate to TGF-β1 at late stage.