摘要
AIM To study the expression of sialylated mucin associated carbohydrate structures in human gastric carcinoma. METHODS Fifty-eight surgical specimens of gastric cancer were obtained. Histologically, there were 24 cases of mucinous carcinoma (including signet ring cell carcinoma and mucinous adenocarcinoma), 15 of well and moderately differentiated tubular adenocarcinoma, 19 of poorly differentiated adenocarcinoma. The lectin binding specific carbohydrates—PSA, WGA, PHA, SBA and SJA were studied by ABC (avidin biotin peroxidase complex) affinity histochemistry staining before and after sialidase treatment. Staining of tissue specimens was estimated using semiquantitative scoring system which not only takes into account tumor heterogeneity and but also is subject to statistical analysis. SAS system software was used for analysis of variance and t test. RESULTS Before neuraminidase treatment, PSA staining was the weakest in three types of carcinoma. WGA staining was intensive in poorly differentiated adenocarcinoma. Both PSA and WGA staining were negative in mucin pool. The staining of PHA, SJA and BSA were more intensive in mucinous carcinoma than that in well moderately differentiated tubular adenocarcinoma and poorly differentiated carcinoma. After neuraminidase digestion, PSA staining showed no change. The staining intensity of WGA decreased, that of PHA, SJA and BSA increased, the increases of the staining intensity of cancer cells which invaded muscle and nerves and cancer cells in cancerous embolus was especially apparent. CONCLUSION The cancer cells of gastric and mucin pool contained the mucin related sialylated carbohydrate structures. The carbohydrate structures were mainly sialylated N-acety-galactosamine and galacto N -acety-galactosamine, which may play an important role in invasion and metastasis of gastric carcinoma.
