SIX1和TGF-β在人喉鳞癌上皮-间质转化中的作用

The role of SIX1 and TGF-βin the epithelial-mesenchymal transition of human laryngeal squamous cell carcinoma

目的检测人喉鳞状细胞癌组织中同源异形框基因(sine oculis homeobox homolog 1,SIX1)、转化生长生子-β(TGF-β)以及E-钙黏蛋白(E-cadherin)的表达,探讨SIX1和TGF-β共同作用对人喉鳞癌上皮-间质转化(epithelial-mesenchymal transition,EMT)的影响及相关作用机制。方法收集术后病理学确诊的人喉鳞癌组织标本96例,瘤体周围正常喉黏膜组织标本32例。应用免疫组织化学方法和蛋白印记Western Blot法检测人喉鳞癌组织及瘤体周围正常喉黏膜组织中SIX1、TGF-β以及E-cadherin蛋白的表达情况,PCR方法检测组织细胞中SIX1、TGF-β以及E-cadherin mRNA表达。分析人喉鳞癌患者临床特征同组织SIX1、TGF-β及E-cadherin蛋白及mRNA表达的关系。结果免疫组化、western Blot、PCR检测均发现,喉鳞状细胞癌SIX1、TGF-β阳性表达率和表达水平均高于癌旁正常黏膜,E-cadherin低于癌旁正常黏膜,差异均有统计学意义(P<0.05)。在低分化、有淋巴结转移的喉鳞癌患者组织中E-cadherin蛋白及其mRNA的阳性表达率较低(P<0.05);在低分化、有淋巴结转移的喉鳞癌患者组织中SIX1蛋白及其mRNA表达率较高(P<0.05);在有淋巴结转移的喉鳞癌患者组织中TGF-β蛋白及其mRNA表达率较高(P<0.05);相关性分析结果显示,人喉鳞癌组织中E-cadherin蛋白及其mRNA的表达与SIX1蛋白及其mRNA表达呈负相关(P<0.05);E-cadherin蛋白及其mRNA与TGF-β蛋白及其mRNA表达呈负相关(P<0.05)。结论SIX1及TGF-β可能是调节人喉鳞状细胞癌上皮-间质转化的重要影响因子,二者的高表达可能共同促进了喉鳞癌的上皮-间质转化,联合检测IX1、TGF-β及E-cadherin对判断人喉鳞癌的转移及预后有重要临床意义。

Objective To detect the expression of sineoculis homeobox homolog 1(SIX1),TGF-βand E-cadherin protein in human laryngeal squamous cell carcinoma(LSCC)tissues,and to explore the combined effects of SIX1 and TGF-βon the epithelial-mesenchymal transition(EMT)of human LSCC and related mechanism of action.Methods A total of 96 specimens of human LSCC confirmed by postoperative pathology,and 32 specimens of normal laryngeal mucosa tissue adjacent to the cancer were collected.The expression levels of SIX1,TGF-βand E-cadherin protein in human LSCC tissue and normal laryngeal mucosa tissue adjacent to the cancer were detected by immunohistochemistry and Western Blot.PCR method was used to detect the expression levels of SIX1,TGF-βand E cadherin mRNA in tissue cells.The correlation between the clinical characteristics of human LSCC and the expressions of SIX1,TGF-βand E-cadherin protein and mRNA was analyzed.Results The results of immunohistochemistry,Western blot and PCR showed that the positive expression rate and expression levels of SIX1 and TGF-βin LSCC tissues were significantly higher than those in normal mucosa adjacent to cancer,however,E-cadherin levels were significantly lower than those in normal mucosa adjacent to cancer(P<0.05).The positive expression rates of E-cadherin protein and mRNA in poorly differentiated LSCC tissues and lymph node metastasis were significantly decreased(P<0.05),however,the positive expression rates of SIX1 protein and mRNA in thses tissues were significantly increased(P<0.05).Moreover the positive expression rates of TGF-βprotein and mRNA in patients with lymph node metastasis of LSCC were significantly increased(P<0.05).The correlation analysis showed that protein and mRNA expression levels of E-cadherin protein and mRNA in human LSCC tissue were negatively correlated with those of SIX1(P<0.05),and the expression levels of E-cadherin protein and mRNA were negatively correlated with those of TGF-β(P<0.05).Conclusion SIX1 and TGF-βmay be important factors for regulating the EMT of human LSCC,and the high expression of the two may promote the EMT of LSCC.Combined detection of IX1,TGF-βand E-cadherin has important clinical significance in judging the metastasis and prognosis of human LSCC.