Alterations of the Mucin Glycoprotein Expression and Their Relationship with the Pathologic Prognostic Factors in Gastric Carcinoma

Roh, Mee Sook; Huh, Gi Yeong; Hong, Sook Hee

Abstract

Alterations of the mucin-type glycoproteins may contribute to changes in cancer cell growth regulation, immune regulation, and cellular adhesion, which in turn may influence the invasive and metastatic capabilities of the cancer. Many of the cancer-associated antigens such as mucin antigens have been identified recently and alterations in the glycosylation of the mucins have been described in the cancer. Immunohistochemical studies of 3 antigens associated with alteration of the mucin glycoprotein (MUC1, MUC2, STn) were done to evaluate their relationship with known pathologic prognostic factors and their usefulness in assessment of the progression of gastric carcinoma in 127 gastric carcinoma tissues. The MUC1 was detected in 57 (44.9%), MUC2 in 76 (59.8%) and STn antigen in 77 (60.6%) out of 127 cases of gastric carcinomas. The expression rate of MUC1 was significantly correlated with depth of tumor invasion, lymph node and distant metastases, and advanced tumor stage (p=0.001). The expression rate of MUC2 was not significantly correlated with pathologic findings and known prognostic factors. The STn antigen was significantly associated with incidence of lymph node metastasis (p=0.02). The coexpression of both MUC1 and MUC2 or MUC1 and STn was more frequent in tumors with deep invasion, lymph node metastasis and advanced tumor stage than one or none expression (p<0.05). These results suggest that the alterations of expression of the mucin proteins, especially MUC1 and carbohydrate antigen (STn) are associated with poor biological behavior of the gastric carcinoma.