Study On The Expression And Clinical Significance Of The E-cadherin Gene Methylation And Protein In Esophageal Squamous Cell Carcinoma

Objective:To detect the E-cadherin gene methylation and protein expression in esophagealsquamous cell carcinoma and corresponding adjacent tissue, explore its relationshipwith clinicopathological data.Methods:Collect the clinical data of50patients with esophageal squamous cell carcinomain the Department of Cardiothoracic Surgery, The First Affiliated Hospital ofNanchang University. Drawn parts of the tumor tissue and corresponding adjacenttissues (normal esophageal mucosa from the tumor>5cm).The genomic DNA fromthese patients was obtained from the frozen tumor specimens and matched normalmucosal tissue specimens using DNA extraction kit. Methylation changed in thepromoter region of E-cadherin gene was determined by using methylation-specificPCR.Immunohistochemical staining of E-cadherin was performed in the tumortissues using SP two-step method. And combined with clinical data to analysis.Informed consent was obtained from each patients.This experiment was approved bythe hospital ethical committee.Results:1. The positive rates of genes promoter hypermethylation of E-cadherin was58%(29/50) in tumor tissue, which was30%(15/50) in normal mucosal tissue. ThePositive rate was significantly higher in tumor tissues than in normal mucosal tissue(X2=7.955,P=0.005). The methylation frequency of E-cadherin in these specimensdid not differ according to the clinical features: age, gender, tumor size anddifferentiation. And it associated with tumor stage and lymph node metastasis2. E-cadherin is mainly expressed on the cell membrane/Cytoplasm in the ESCC,the positive rates of protein expression of E-cadherin was40%(20/50), E-cadherinexpressed in these specimens did not differ according to the clinical features: age,gender, tumor size and differentiation. And it associated with tumor stage and lymphnode metastasis 3.The promoter hypermethylation of E-cadherin gene was remarkably associatedwith the loss of protein (P=0.001,r=-0.463).Conclusion:1. Promoter hypermethylation of E-cadherin is common in ESCC and occursmore frequent in tumor tissues than in normal mucosal tissues. E-cadherin genepromoter methylation may be involved in the malignant lesions process of ESCC.2. The methylation E-cadherin is associated with loss of protein,the promptedintercellular adhesion loss involved in the process of tumor development.3.The promoter hypermethylation of E-cadherin gene is remarkably associatedwith the loss of protein.