Expression and significance of adenomatous polyposis coli, beta-catenin, E-cadherin and cyclin D1 in esophageal squamous cell carcinoma assessed by tissue microarray.

Background and Objective: The genesis of esophageal squamous cell carcinoma(ESCC)is a multifactor and multistage process, in which Wnt signaling transduction pathway plays an important role in tumorigenesis and tumor progression. This study was to investigate the roles of four proteins in the Wnt pathway in tumorigenesis of ESCC, and their significances in the early diagnosis of ESCC.
Methods: The expression of adenomatous polyposis coli (APC), beta-catenin, E-cadherin and cyclinD1 was detected by immunohistochemistry using tissue microarrays consisting of 199 specimens of ESCC, 164 specimens of normal mucosa, 34 specimens of basal cell hyperplasia and 30 specimens of dysplasia adjacent to cancer tissues.
Results: The positive rates of APC and E-cadherin in ESCC were lower than those in the normal group (69.6% vs. 98.0%, p < 0.01; 19.6% vs. 96.3%, p < 0.01). The abnormal expression rates of beta-catenin and cyclin D1 in ESCC were higher than those in the normal group (65.5% vs. 1.2%,p < 0.01; 70.9% vs. 0.8%, p < 0.01). In accordance with the following order, normal epithelia --> basal cell hyperplasia --> dysplasia --> ESCC, hypoexpression of APC proteins occurred in ESCC, abnormalities of beta-catenin and E-cadherin started to appear in dysplasia, and overexpression of Cyclin D1 emerged from basal cell hyperplasia. From well to poorly differentiated ESCC, the expression of APC, E-cadherin and cyclin D1 were gradually reduced, while beta-catenin was increased. The expression of beta-catenin was not correlated with APC (r = -0.10, p > 0.05), was negatively correlated with E-cadherin (r = -0.31,p < 0.01) and positively correlated with cyclin D1(r = 0.49, p < 0.01).
Conclusion: APC, E-cadherin, beta-catenin and cyclin D1 may play important roles in tumorigenesis of ESCC. Therefore, detection of E-cadherin, beta-catenin and cyclin D1 proteins may be helpful for the early diagnosis of ESCC.