| IntroductionGastric carcinoma is a serious disease in China and mortality rate is very high . But there is no suitable gastric carcinoma marker. Mucin (MUC) is important part of gastric mucus. Most studies have shown that abnormal mucin expression is found in progress of gastric carcinoma. Vascular endothelial growth factor (VEGF) is a very important factor in tumor angiogenesis and is closely related to many physiological and pathological processes. In this study, we performed immunohistochemical staining for MUC2, MUC5AC, VEGF - C and He-licobacter (H. pylori) in sections of gastric carcinoma and pericancerous muco-sa in order to discover their relations and provide scientific proof for evaluating patients prognosis.MaterialFifty patients who had undergone surgical resections of gastric carcinoma were selected for our study. We examined sections from gastric carcinoma and pericancerous mucosa. The study cohort consisted of 28 men and 22 women ( mean age 58years, range 35 - 80) and included 21 cases of well and moderate differentiated cancer, 23 cases of poorly differentiated cancer, 3 cased of undif-ferentiated cancer, 3 cases of ring cell cancer. Lymph node metastasis was found in 31 patients.Main reagents: Anti - Human Mucin2, Anti - Human Mucin5AC, Rabbit Anti - VEGF - C, Polyclonal Rabbit Anti - Helicobacter Pylori, UltraSensi-tive?SP Kit.Main instruments: Microscope, low - temperature refrigeratorMethodMethod: HE staining was performed for pathological diagnosis. The expression of MUC2, MUC5AC, VEGF - C and H. pylori was determined by SP im-munohistochemical method.Statistic Analysis;SPSS12. 0 statistic software was applied. All data were analyzed with x test and p <0.05 was regarded as statistically significant.Results— AExpression of MUC2, MUC5AC,VEGF - C in cancerous and pericancerous mucosaThe positive rate of MUC2 expression in cancerous and pericancerous mucosa are 60% and 58%. No association was found between two groups (P >0. 05). Significant difference was found between the expression of MUC5AC in cancerous(42% ) and pericancerous mucosa(90% ,P<0.01). Same difference was also found between the expression of VEGF - C in cancerous (72% ) and pericancerous mucosa(46% ,P <0.01)._HA Expression of MUC2, MUC5AC, VEGF-C and H. pylori infection H. pylori positive was found in 28 cases (56% ) . The expression of MUC2 in pericancerous mucosa was significantly different between H. pylori positive group(71.43% ) and H. pylori negative group(40. 90% , P <0. 05). As to the expression of MUC5 AC and VEGF - C, no association was found between H. pylori positive group and H. pylori negative group(P >0.05).izi^ Expression of MUC2, MUC5AC, VEGF - C and lymph node metastasis Positive staining of VEGF - C was found in 26 out of 31 patients in lymph node metastasis group(83. 87% ), whereas only 10 cases showed VEGF - C expression in 19 lymph node metastasis negative group (52. 63% ) . There is correlation between VEGF - C expression and lymph node metastasis ( P < 0. 05 ). No association was found between MUC2, MUC5 AC expression and lymph node metastasis(P > 0.05 ).K ^Expression of MUC2, MUC5AC, VEGF - C and grade of differentiation The positive rate of MUC2 expression in well and moderated differentiated cancers ( 80. 95)% was higher than that in poorly ,differentiated , undifferenti-ated and ring cell cancers(44. 83% , p <0. 05). No association was found between MUC5AC, VEGF-C expression and cancers differentiation(P >0.05).DiscussionMucin is secreted by many kinds of epithelial cells. Mucin secreted by gastric epithelial cell is an important component of mucus . They can protect and lubricate epithelial surfaces. Studied in recent years showed that their functions involve epithelial renewal, maintaining epithelial integrality and carcinogenesis . MUC5AC is positive in nearly all the normal gastric mucosa. MUG2 is positive in intestinal mucosa and negative in gastric mucosa. In intestinal metaplasia, MUC5AC expression decreases and MUC2 expression increase. In gastric carcinoma, MUC5AC expression also decreases . MUC2 expression is lower than in intestinal metaplasia. VEGF is composed of a family whose function is angiogen-esis. VEGF - C is an important member and has another function of lymphangio-genic actions. In advanced gastric carcinoma , VEGF - C expression correlate with lymphatic invasion, lymph node metastasis and in some reports, venous invasion . H. pylori has been classified by the World Health Organization (WHO) as a class I carcinogen . Studies had demonstrated that H. pylori infection promoted the cause of gastric carcinoma in laboratory.In our study , we detected MUC2,MUC5AC,VEGF -C expression and H. pylori infection with SP immunohistochemical method. In conclusion, MUC5AC expression markedly decreases in gastric cancer. MUC2 expression , which is negative in normal gastric tissue , is positive in gastric carcinoma especially in well and moderated differentiated cancers. VEGF - C expression in lymph node metastasis group is higher than that in lymph node metastasis negative group. MUC2^MUC5AC and VEGF - C may be suitable marker in studying gastric car-cinoma. H. pylori infection caused the abnormal expression of MUC2 in peri-carcerous mucosa, but might not alter expression of MUC2 and MUC5AC in gastric carcinoma.Conclusion1. MUC5AC espression markedly decreases in gastric cancer;MUC2 expression is related to grade of cancer' s differentiation.;There is correlation between VEGF-C expression and lymph node metastasis 5MUC2..MUC5 AC and VEGF- C may be suitable marker in studying gastric carcinoma.2. H. pylori infection may alter the expression of MUC2 in pericarcinomous tissue.
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