Expression and Significance of CDC25 Phosphatases and Smad3 Protein in Human Esophageal Squamous Cell Carcinoma

Objective: To study the expression of CDC25 phosphatases (CDC25A, CDC25B) and Smad3 in esophageal squamous cell carcinoma and to analyze their relationship with the clinical pathological features. Methods: Immunohistochemistry (SP) was used to detect the expression of CDC25A and CDC25B in 52 specimens of esophageal squamous cell carcinoma and their adjacent mucosa (24 specimens of normal esophageal epithelium, 25 specimens of dysplasia, and 52 specimens of infiltrative esophageal squamous cell carcinoma). Flow cytometry (FCM) was employed to detect CDC25A, CDC25B and Smad3 proteins. SPSS11.5 was used to analyze the experimental data. Results: The positive expression rates of CDC25A and CDC25B were lower in dysplasia and normal tissues than in esophageal squamous cell carcinoma (P0.01). No significant difference was found in CDC25A and CDC25B positive expression rates between dysplasia and normal tissues (P0.05). In esophageal squamous cell carcinoma, the CDC25A and CDC25B protein levels were higher in the cases with fibromembranous infiltration or moderate/poor differentiation than in the cases without fibromembranous infiltration or with high differentiation (P0.01). The CDC25A protein level was significantly higher in patients with lymphatic metastasis than in patients without lymphatic metastasis (P 0.01). CDC25B protein expression was not related to lymphatic metastasis (P0.05). The positive expression rate of Smad3 was higher in dysplasia and normal tissues than in esophageal squamous cell carcinoma (P 0.01). No significant difference was found in Smad3 positive expression rates between dysplasia and normal tissues (P0.05). There was a negative correlation between Smad3 and CDC25A expression (r=-0.482, P= 0.007). Conclusion: The abnormal expression of CDC25A may be involved in the oncogenesis and metastasis of esophageal carcinoma. Detection of CDC25A may provide information for evaluating the malignancy and metastatic potential of esophageal carcinoma. The expression levels of CDC25A and Smad3 are negatively correlated. CDC25B may play a role in the early phase of esophageal carcinoma.