Expression And Significance Of MUC2 In Human Carcinoma Of Stomach And Gastric Epithelial Dysplasia

Objective:Carcinoma of stomach shows the highest disease rate in tumor of digestive system ,and at the first place of cancer death rate in china. It's generally acknowledged that gastric epithelial dysplasia is one of precarious lesions.MUC2( Mucin 2 Glycoprotein)expresses in carcinoma of stomach but not normal gastric mucosa. We analyzed biological significance of MUC2 in carcinoma of stomach,precarious lesion and investigated the relationship between carcinoma of stomach and gastric epithelial dysplasia in order to find a theoretical evidence for the diagnosis about carcinoma and precarious lesion of stomach by MUC2.Materials and Methods:20 cases of carcinoma of stomach specimens and 18 cases of gastric epithelial dysplasia(GED) mucosa specimens were obtained surgically. 20 cases of normal gastritis specimens were selected as controlling group. All samples were fixed with 100ml/L formalin , embedded with paraffin and sectioned serially(5μm). HE (Hematoxylin and eosin )method was applied to test the differentiation classifications of carcinoma of stomach .The expressions of MUC2 was detected by immunohistochemical method(S-P method).Using PBS instead of first antibody as negative control. DBA for coloring. The positive result of MUC2 shown brown-yellow color in positive cell .Observed target:1. Expression of MUC2 in carcinoma of stomach,gastric epithelial dysplasia and normals.2. Expression of MUC2 in different histological types of carcinoma of stomach.3. Expression of MUC2 in different stages of GED in gastric mucosa tissues. Statistics:SPSS13.0 was used to deal with all the data. The laboratory datas were analyzed by chi-square criterion ,Kruskal-Wallis test or Fisher's exact propability test. A value of P <0.05 was considered statistically significant.Results:1. The cell stain intensity of MUC2 in different histological types of carcinoma of stomach are attenuating sequenced from mucinous adenocarcinoma , signet-ring cell carcinoma, adenocarcinoma and poorly differentiated adenocarcinoma . There is vary significant difference by Kruskal-Wallis test (H=23.518, P =0.001).2.Expression of MUC2 was 33.33%(3/9) in midrange of GED,88.89% in the highest stage tissue. There exists a overexpression. There is vary significant difference by Fisher's exact propability test. (P =0.025)3. The positive expression rate of MUC2 in carcinoma of stomach, GED and normal gastritis are 70.00%(14/20), 61.11%(11/18), 0.00%(0/20) respectively .There was vary significant difference statistically by Fisher's exact propability test between normal and carcinoma,and GED (P <0.05);there's no significant difference statistically between carcinoma of stomach and GED (P >0.05),but significant difference statistically between carcinoma of stomach and GED in cell stain intensity(P=0.013).Conclusions:1.MUC2 is overexpressed in carcinoma of stomach and there exists an difference of different histology classifications,it would be one marker of gastric mucinous adenocarcinoma.2. MUC2 is overexpressed in some precarious lesion and exists an difference between stages,more malignant more expression .3. MUC2 might contribute to tumorigenesis growth in carcinoma of stomach.