Expression And Clinical Significance Of Tight Junction Associated Proteins In Brain Metastases From Lung Cancer

Objective:The aim of this study was to investigate the relationship between Blood-brain barrier tight junction proteins Claudin-5, Occludin and Zo-1 expression and clinicopathologic parameters in brain metastases from lung cancer. Methods:Envision immunohistochemistry was used to detect the expression of Claudin-5?Occludin and Zo-1 protein in 63 brain metastases from lung cancer and 28 normal brain tissue.The correlation of Claudin-5,Occludin and Zo-1 expression with clinical characteristics and prognosis was determined by statistical analysis. Results:1.Claudin-5 mainly expressed in plasma membrane. The expression of Claudin-5 in brain metastases tissue and normal brain tissue were50%?25.4%. It has statistically significantly difference between them(?2=5.310, P=0.021).The expression of Claudin-5 in brain metastases from lung cancer showed obvious correlation with patients' age and the number of metastases,but without relation to gender,pathologic types of primary lesion?metastases size(P>0.05).2.Occludin mainly expressed in plasma membrane. The expression of Occludin in brain metastases tissue and normal brain tissue were 7.1%, 34.9%. It has statistically significantly difference between the two tissue(?2=3.936,P=0.047).The expression of Occludin in brain metastases from lung cancer was closely related to patients' age and the number of metastases,but without relation to gender pathologic types of primary lesion?metastases size(P>0.05).3.The expression of Zo-1 in brain metastases tissue and normal brain tissue were 75%?33.3%. It has statistically significantly difference between them(?2=13.542,P<0.001).The expression of Zo-1 in brain metastases tissue showed obvious correlation with patients' age and the number of metastases,but there were no evident relationship between people's gender,pathologic types of primary lesion,metastases size and the expression level of tight junction protein(P>0.05).4.In brain metastases tissue,high expression level of tight junction proteins was related to longer survival time(P<0.05).5.Spearman correlation analysis showed a positive correlation between the expression of Claudin-5,Occludin and Zo-1 in brain metastases tissue from lung cancer(P<0.05). Conclusion:Blood-brain barrier tight junction associated proteins Claudin-5,Occludin and Zo-1 were expression lower in brain metastases from lung cancer than normal brain tissue,and the expression level of the proteins were associated with patients' survival time.It means that decreased expression of Claudin-5,Occludin and Zo-1 may play an important role in the occurrence of brain metastasis from lung cancer,and combined detection of Claudin-5,Occludin and Zo-1 protein could help to evaluate the prognosis of brain metastases from lung cancer and provide theoretical basis for its treatment.