RESUMEN
OBJECTIVE: To explore the expression and clinical significance of signal protein Sema4C in esophageal cancer, gastric cancer and rectal cancer. METHODS: Fifty esophageal cancer, 75 gastric cancer, 50 rectal cancer and 20 corresponding normal mucous membrane specimens, collected during the period of January 2008 to December 2010, were detected with streptavidin-peroxidase immunohistochemistry to detect the expression levels of Sema4C. And the relationships of the Sema4C expression with clinicopathological data was analyzed. RESULTS: The expression levels of Sema4C in three kinds of cancers were significantly higher than the corresponding normal mucous membranes (80.0% (n = 40) vs 20.0% (n = 4), 77.3% (n = 58) vs 25.0% (n = 5), 80.0% (n = 40) vs 15.0% (n = 3), all P = 0.000). Furthermore, the percentage of Sema4C positive cells was significantly higher in carcinoma nests of tumors with lymphatic metastasis than those without (90.3% (n = 28) vs 63.2% (n = 12), 85.0% (n = 51) vs 46.7% (n = 7), 92.0% (n = 23) vs 68.0% (n = 17), P = 0.049, 0.005, 0.034). However, no significant correlations were found between the Sema4C expression with gender, age, location of tumors, types of cancer cells, cell differentiation, tumor size, depth of invasion or tumor stage (all P > 0.05). CONCLUSION: There is a high expression of Sema4C in esophageal cancer, gastric cancer and rectal cancer. And it is strongly correlated with lymphatic metastasis. Thus Sema4C may play critical roles in the invasion and lymphatic metastasis of esophageal cancer, gastric cancer and rectal cancer.