TGF-β1和N-cadherin在精原细胞瘤中的表达及二者的关系

The expression and correlation of TGF-β1 and N-cadherin in seminoma

目的检测转化生长因子-β1(TGF-β1)及神经-钙粘素(N-cadherin)在精原细胞瘤中的表达并探讨二者关系。方法采用SP免疫组化法检测34例精原细胞瘤及15例正常睾丸中TGF-β1、N-cadherin的表达水平。构建N-cadherin质粒载体,转染NCCIT精原细胞瘤细胞系,经外源性人重组TGF-β1干预,荧光法检测N-cadherin的表达。结果免疫组织化学染色结果显示,正常睾丸间质细胞、生精上皮细胞、长形精子及支持细胞间紧密连接处均可见TGF-β1表达,N-cadherin则表达于支持细胞间紧密连接处。精原细胞瘤中未见N-cadherin表达,但TGF-β1表达水平较正常睾丸显著增高,且差异有显著性(P<0.05);TGF-β1可降低精原细胞瘤细胞株中N-cadherin的表达水平。结论精原细胞瘤中TGF-β1高表达,N-cadherin低表达,且重组TGF-β1可降低精原细胞瘤细胞系N-cadherin表达,提示TGF-β1可能通过下调N-cadherin在精原细胞瘤癌变过程中起重要作用。

Objective To investigate the expression and correlation of transforming growth factor-β1（TGF-β1）and Ncadherin in seminomas.Methods The expressions of TGF-β1 and N-cadherin in34 seminoma tissues and 15 normal testicular specimens were detected with immunohistochemical staining.Plasmid vector of N-cadherin was constructed,and NCCIT cells were transfected.The NCCIT cells were cultured for 2 days with TGF-β1 nutrient medium and the expression of N-cadherin was detected with fluorescence technique.Results TGF-β1 was detected in Leydig cells,seminiferous epithelial cells,sperms and sertoli cells of testis tissues.N-cadherin was detected in tight junctions（TJs）and adherin junctions（AJs）between sertoli cells.Immunohistochemical staining did not detect N-cadherin in seminomas.Immunohistochemical staining results showed that the expression of TGF-β1 was significantly increased in seminoma compared with that in normal testis tissues（P〈0.05）.Immunofluorescence staining results showed that TGF-β1 could significantly down-regulate the expression of N-cadherin in NCCIT.Conclusions UP-regulated TGF-β1 and down-regulated of N-cadherin are detected in seminomas,which indicates that TGF-β1 plays an important role in tumorigenesis of seminomas by regulating the expression of N-cadherin.