The Significance Of The Expression Of Mucins (MUC1,MUC2,MUC5AC) And E-Cadherin In Gastric Carcinomas

OBJECTIVE:To investigate the significance of the expression of mucins (MUC1, MUC2, MUC5AC ) and E-cadherin in primary gastric cancers.METHODS: These proteins were detected by immuno-histochemistry S-P method. RESULTS: The rate of the MUC1 gene expression was 82% (77/94), MUC2 was 84%(79/94), MUC5AC gene expression was 40%(38/94) and E-cadherin was 56%(53/94).The expression of MUC1 was related with the different types of the cancer, patients' age, involvement of the lymph nodes and the tumor size(P<0.05); The MUC2 expression was significantly related with the different types of the cancer and had the strongest expression in mucinous carcinomas(P<0.05), but it had no significant difference in patients' age, gender ,the location of the tumor, involvement of the lymph nodes, the depth of gastric wall invasion and the metastasis to extra-gastric organs(P>0.05); MUC5AC expression was not related with any of the characteristics investigated at present except it had the difference in gender group(P<0.05) ,however, it had the tendency that it was higher in the less invasive gastric carcinoma tissues than it in the advanced tissues; As for theexpression of E-cadherin, we didn't find any significant difference in the present studied behaviors; Besides these findings mentioned above, there was strong positive relationship between MUC1 and E-cadherin, MUC2 and E-cadherin and MUC1 and MUC2. According to the COX proportional hazards model analysis, the advanced age of patients, the involvement of lymph nodes, the different types of gastric cancers and the MUC2 expression are significantly associated with poorer outcome of the gastric carcinoma patients. CONCLUSION: MUC1,MUC2 were good markers of different types of gastric cancer; MUC1 had the strongest expression in the well and moderately differentiated tubular carcinomas, and had a relationship with the interfered lymph nodes, tumor size and patients' age; MUC2 was a excellent marker of mucinous carcinoma and well and moderately differentiated gastric cancers, it also had the independent role in predicting a poor prognosis of gastric cancer patients; MUC5AC may be a good marker in studying the progress of gastric carcinoma since it seemed decreased more in advanced gastric cancers; but the expression of E-cadherin had no clear relation with the cancer's behaviors which were studied at present. Moreover, there was a positive relationship between MUC1 and E-cadherin, MUC2 and E-cadherin and MUC1 and MUC2, so MUC1 and MUC2 may have the synergic influence on the E-cadherin and MUC5AC's function especially when we can see that in the mucinous cancers the expression of MUC1 and MUC2 were higher while the the MUC5AC and E-cadherin were lower, therefore MUC1 and MUC2 may contributed to the progress of the gastric cancer especially in mucinous gastric cancers.