Expression Of sialosyl-Tn Antigen Research Articles

Prognostic value of expression of sialosyl-Tn antigen in colorectal carcinoma and transitional mucosa.

We examined the immunohistochemical expression of sialosyl-Tn antigen in the colorectal cancer tissues of 116 patients who underwent curative resection to determine the association between patient prognosis and the expression of sialosyl-Tn in two different tissues: carcinoma and transitional mucosa. Negative or positive expression of sialosyl-Tn in the carcinoma and transitional mucosal tissues were denoted as CA- or CA+ and TM- or TM+, respectively. Patients were classified into one of four groups: CA-/TM-, CA-/TM+, CA+/TM-, and CA+/TM+. CA-/TM- was observed in 13 patients and CA-/TM+, CA+/TM-, or CA+/TM+ was observed in 103 patients. The difference in five-year survival between the CA-/TM- group and all the other groups was statistically significant (P = 0.0457), and multivariate analysis showed that sialosyl-Tn expression in at least one of the two tissues was an independent prognostic factor. We conclude that the evaluation of sialosyl-Tn expression in carcinoma as well as transitional mucosa is useful for predicting survival in colorectal cancer patients.

Predictive evaluation of preoperative serum sialosyl-Tn antigen expression in the patients with advanced gastric cancer

Predictive evaluation of preoperative serum sialosyl-Tn antigen expression in the patients with advanced gastric cancer

Expression of Sialosyl-Tn Antigen in Breast Cancer & Its Correlation with Prognostic Parameters

Expression of Sialosyl-Tn Antigen in Breast Cancer & Its Correlation with Prognostic Parameters

Immunohistochemical detection of sialosyl-Tn antigen in carcinoma of the prostate.

To investigate the expression of sialosyl-Tn antigen (STn) in human benign and malignant prostate. The expression of STn was investigated immunohistochemically in formalin-fixed and paraffin-embedded tissue specimens from 56 patients with primary prostatic adenocarcinoma (median age 74.3 years, range 47-89) and 20 patients with benign prostatic hyperplasia (median age 73.4 years, range 60-87). STn was expressed in only three (4%) of the 20 hyperplastic glands and the benign areas adjacent to the 54 carcinomas; by contrast, STn was expressed in 34 (61%) of the 56 carcinomas. The frequency of STn positivity was much higher in well-differentiated carcinomas than in those poorly differentiated. STn is expressed with malignant transformation of the prostatic epithelial cells and immunohistochemical methods using commercially available STn monoclonal antibody may be useful as an adjunct for distinguishing carcinoma from benign tissue.

Reciprocal control of colon-specific sulfomucin and sialosyl-Tn antigen expression in human colorectal neoplasia.

Histochemical reports claim that sulfomucins decrease and sialylated mucins increase during colon carcinogenesis. We examined the expression of colon-specific sulfomucins and sialosyl Tn antigen (STN) in normal small intestine, normal colorectal mucosa and colorectal tumours at different stages of progression immunohistochemically, using MAb 91.9H specific for colonic sulfomucins and MAb TKH-2 for STN. No expression of sulfomucins recognized by MAb 91.9H was found in normal small intestine, whereas STN staining was pronounced. The converse was the case in normal colorectal mucosa. Sulfomucins were still found in adenomas, but the amounts decreased with depth of invasion in cancers (P < 0.001). In contrast, no STN could be detected in benign lesions, but staining became increasingly evident with invasion (P < 0.001). This reciprocal control of expression of colon-specific sulfomucins and STN evident in tumour progression indicates that the mucous phenotype shifts from the colonic to the small intestinal type.

Sialosyl Tn antigen expression is associated with the prognosis of patients with advanced gastric cancer

Sialosyl Tn antigen expression is associated with the prognosis of patients with advanced gastric cancer

Sialosyl Tn antigen expression is associated with the prognosis of patients with advanced gastric cancer

Sialosyl Tn antigen expression is associated with the prognosis of patients with advanced gastric cancer

Sialosyl-Tn antigen is prevalent and precedes dysplasia in ulcerative colitis: A retrospective case-control study

BACKGROUND & AIMS: Expression of the carbohydrate-associated sialosyl- Tn (STn) antigen has been correlated with carcinogenesis in sporadic colon cancer. This retrospective study analyzed surveillance colonoscopy biopsy specimens to determine whether STn antigen could serve as a marker for neoplasia risk in patients with long-standing ulcerative colitis. METHODS: Eleven patients who developed dysplasia or cancer and who had undergone at least three surveillance colonoscopies were matched with 11 controls who had not developed neoplasia. Sections from 969 available surveillance biopsy specimens were stained immunohistochemically with monoclonal antibody TKH2 and were interpreted blindly. RESULTS: Compared with controls, patients expressed STn antigen more frequently in their biopsy specimens (44% patient biopsy specimens vs. 11% control biopsy specimens). Patients were also more likely to undergo colonoscopies with two or more colonic segments expressing STn antigen (73% vs. 22%), repeated STn antigen expression in two or more consecutive colonoscopies (91% vs. 27%), and STn antigen expression proximal to the hepatic flexure (64% vs. 0%). STn antigen appearance preceded the detection of neoplasia by 7 or fewer years, and its preferential expression in patients was not confounded by the degree of active inflammation. CONCLUSIONS: Repeated STn antigen expression in nondysplastic colonic mucosa may presage the development of neoplasia in long-standing ulcerative colitis and may be a useful adjunct to dysplasia during colonoscopic surveillance. (Gastroenterology 1996 Mar;110(3):694-704)

Sialosyl Tn antigen expression is associated with the prognosis of patients with advanced gastric cancer.

Several studies have revealed a correlation between sialosyl Tn antigen (STN) and certain clinicopathologic features of various cancers, and that STN is an independent prognostic factor. However, the clinical significance of the expression of STN in gastric cancer has not been reported. Thus, the purpose of this study was to evaluate immunohistochemically the clinical significance of expression of STN in gastric cancer. The expression of STN in surgically resected specimens of human gastric cancer was evaluated immunohistochemically using a monoclonal antibody (TKH-2), in 60 patients whose serum STN levels were measured and in 54 patients with advanced cancer who had been followed for more than 5 years after gastrectomy. The correlations between the level of STN expression and clinicopathologic factors were analyzed. The staining intensity was graded as follows: (-), less than 5% of the cancer cells expressed STN; (+), 5-50%; (++), more than 50%. Sialosyl TN antigen staining was detected mainly on the cell membrane, in the cytoplasm, and in the luminal contents, and 57.2% of the 60 specimens expressed STN, whereas the corresponding value for positive serum levels was 15%. A higher percentage of advanced tumors expressed STN than did the early cases, but the difference was not statistically significant. All cases with strong staining, the (++) cases, were advanced cases either with lymph node metastases or with cancer invading in or beyond the muscle layer proper. The expression of STN appeared to be related to the clinical stage, the extent of cancer invasion, and the presence of lymph node metastases. Sialosyl TN antigen was detected in the serum in less than 6% of the patients whose tumors were (-) or (+) for STN expression, and in 86.7% of the patients whose tumors expressed high levels of STN (++). The estimated 5-year survival in advanced cases (Stage III) was significantly better in those with negative STN expression than in those with positive STN expression (P < 0.01). These results suggest that STN may be a useful marker associated with the prognosis of patients with advanced gastric cancer.

Sialosyl-Tn antigen: Initial report of a new marker of malignant progression in long-standing ulcerative colitis

Background & Aims: Expression of the mucin-associated carbohydrate antigen sialosyl-Tn (STn) correlates with malignant transformation in sporadic colonic neoplasms. The aim of this study was to analyze STn antigen expression in patients with long-standing ulcerative colitis (UC). Methods: STn antigen was assessed by immunohistochemistry in archival tissues. Study A was a retrospective chronological case-control study. Serial surveillance colonoscopic biopsy specimens without inflammation or dysplasia were analyzed in 7 patients who developed colon cancer and in 8 controls who did not develop colon cancer. Study B analyzed the anatomic distribution of STn expression in 17 cancer-bearing (case) and 6 cancer-free (control) colectomy specimens from patients with UC. In some colectomy specimens, STn was compared with aneuploidy, which was determined by flow cytometry. Results: In study A, among the 7 patients with UC who developed cancer, 6 patients (86%) expressed STn in at least one prior nondysplastic surveillance biopsy specimen from the same site. Only 3 of 8 control patients (38%) expressed STn. In study B, STn was expressed in 40 of 82 specimens (49%) from cancer-bearing colons but only 8 of 62 specimens (13%) from cancer-free colons. STn was expressed in most aneuploid areas but was also found in diploid, nondysplastic mucosa. Conclusions: STn antigen seems to be a promising marker of cancer risk in patients with UC.

Trichosanthes Japonica Agglutinin I Staining of Human Colonic Carcinoma: A Comparative Study Using Monoclonal Antibody Against Sialosyl-Tn Antigen.

Trichosanthesjaponica agglutinin I (TJA-I) having a high affinity to the NeuAcα2-6Galβ1-4GIcNAc terminal sequence was used for an immunohistochemical study to analyze the expression of the NeuAcα2-6Gal structure in human colonic tissues. A TJA-I binding substance was detected in the mucosa of colonic carcinoma, but not in the normal and transitional mucosa. The TJA-I staining was correlated with the degree of histo logical differentiation of the carcinoma. TJA-I preferentially stained well-differentiated and moderately differentiated adenocarcinoma. In the carcinoma containing mucin lakes, the TJA-I staining reaction was either weak in intensity or negative. A comparative study using monoclonal antibody against sialosyl-Tn antigen (NeuAcα2-6-GaINAc) known to be expressed in colonic carcinoma tissues revealed that the areas exhibiting strong expressions of siaosyl-Tn antigen separated from the areas vividly reactive for the TJA-I staining. In addition, the expression of sialosyl-Tn antigen, unlike the TJA-I staining, was strong in the mucinous areas of the carcinoma. The results obtained in the present study suggest the possibility that a comparative staining method with TJA-I and monoclonal antibody against sialosyl-Tn antigen could be helpful to the diagnosis of human colonic carcinoma.

Expression of sialosyl-Tn antigen (monoclonal antibody MLS102 reactive) in normal tissues and malignant tumors of the digestive tract.

Oncogenic transformation is often associated with changes in the glycosylation state of malignant cells. We investigated the immunohistochemical localization of sialosyl-Tn antigen [O-linked NeuAc(alpha 2-->6)GAINAc] using a novel monoclonal antibody MLS102 in normal and malignant digestive-tract tissues. In normal tissues, weak MLS102 immunoreactivity was observed in the epithelium of the esophagus, stomach and colon. However, MLS102 immunoreactivity was strong in the goblet cells of the duodenum, but not in the Brunner glands. In carcinomas of the esophagus, stomach, colon, pancreas and biliary tract, positive staining was detected with a high frequency (80%-100%). In mucinous carcinomas and signet-ring cell carcinomas, malignant cells themselves and the mucins they secreted were strongly positive for sialosyl-Tn antigen. There was no significant correlation between the frequency of expression of sialosyl-Tn antigen and the degree of differentiation (grade). However, in the case of well-differentiated adenocarcinomas, sialosyl-Tn antigen was found mainly in the supranuclear areas (Golgi area), on the apical surface and in the adjacent cytoplasm. In poorly differentiated adenocarcinomas, the antigen was often detected in the whole plasma membrane and cytoplasm. Therefore, monoclonal antibody MLS102 may be useful in further elucidating the characteristics of digestive-tract cancers, and possibly in their treatment.

Mucin-associated sialosyl-Tn antigen expression in gastric cancer correlates with an adverse outcome.

The expression of sialosyl-Tn (STn) antigen was evaluated by immunohistochemistry in primary gastric cancers. Twenty-one of 31 (68%) gastric cancers expressed STn, regardless of tumour location, stage or histological type. Eighty-one per cent of patients with STn-positive tumours died of their disease or had recurrent cancer, compared with 20% of patients with STn-negative tumours (P < 0.002). STn may be a useful prognostic marker in patients with gastric cancer.

Association between expression of sialosyl‐Tn antigen and intestinalization of gastric carcinomas

We examined immunohistochemically the expression of sialosyl-Tn antigen (STN) in 137 primary gastric carcinomas. In the non-neoplastic mucosa, STN was expressed in all goblet cells, most absorptive cells and Paneth cells of intestinalized tubules, whereas it was not seen in the gastric mucosa proper. We evaluated the association between the mucin-histochemical findings of intramucosal carcinomas and the STN-expression. STN was expressed in 8 of 20 undifferentiated-type carcinomas, all of which were mucin-histochemically of the gastric type. STN was expressed in 25 of 51 differentiated-type carcinomas, among which it was expressed in 3 of 12 gastric-type, 11 of 17 intestinal-type and 11 of 22 mixed-type adenocarcinomas. The extent of STN expression in the intestinal-type adenocarcinomas was significantly higher than in gastric-type adenocarcinomas and undifferentiated-type carcinomas, and that seen in mixed-type adenocarcinomas was significantly higher than in the gastric-type adenocarcinomas. We also examined STN expression in early and advanced carcinomas. As the depth of carcinoma invasion progressed, the extent of STN expression was significantly higher and its incidence was significantly higher. Our findings suggest that STN expression reflects intestinalization of the gastric mucosa, and that a kind of intestinal metaplasia occurs in progressing gastric carcinoma cells.

Sialosyl-Tn antigen. Its distribution in normal human tissues and expression in adenocarcinomas.

In normal adult human tissues, sialosyl-Tn antigen, detected by monoclonal antibody TKH2, was uniformly found in the bronchus, uterus, salivary gland, palatine tonsil, testis, stomach, duodenum, and capillary endothelium of several organs. It was also sporadically found in the small intestine, appendix, colorectum, gallbladder, urinary bladder, skin, and esophagus. The antigen was absent in the other organs. Even in the organs showing positive findings, the antigen was observed only in the limited areas. In contrast, sialosyl-Tn antigen was expressed in a large number of adenocarcinomas in many kinds of organs. It was expressed in more than one half the adenocarcinomas of the pancreas, ovary, uterus, stomach, colorectum, and gallbladder, but not in hepatocellular carcinomas, renal cell carcinomas, and papillary carcinomas of the thyroid gland. Sialosyl-Tn antigen expression also was observed in intestinal metaplasia of the stomach and in transitional mucosa adjacent to the colorectal carcinoma, which are considered to be cancer-related lesions. These results indicate that sialosyl-Tn antigen is a useful tumor marker, especially in adenocarcinomas of the mucin-producing organs, and suggest that the regulation of sialosyl-Tn antigen synthesis in adenocarcinomas is different from that in normal tissues.

Mucin associated Tn and sialosyl-Tn antigen expression in colorectal polyps.

Sialosyl-Tn antigen and its immediate precursor, Tn antigen, are carbohydrate structures associated with the earliest steps of mucin O-linked glycosylation. Both antigens have been shown previously to be highly sensitive and specific markers of colorectal cancer. One hundred and three colorectal polyps (79 adenomatous; 24 hyperplastic) were examined for expression of Tn antigen using vicia villosa isolectin B4, and for sialosyl-Tn antigen by monoclonal antibody TKH2. Tn antigen was expressed by all of the polyps studied. Sialosyl-Tn, on the other hand was expressed weakly by a few cells in 7 of 24 (29%) hyperplastic polyps. Among the adenomatous polyps, 56% expressed sialosyl-Tn and expression correlated with larger adenoma size, greater villous component, and more severe grades of dysplasia. In individuals with two or more synchronous adenomas, the level of sialosyl-Tn expression within an adenoma was associated with the severity of cytological atypia. All the adenomas that contained a focus of invasive carcinoma expressed sialosyl-Tn. These results indicate that colorectal polyps manifest incomplete glycosylation, exposing antigens in the innermost region of mucin oligosaccharides. In addition, the correlation of sialosyl-Tn antigen expression with the adenoma-carcinoma sequence may make this a useful marker for studying malignant progression in the colon.

Sialosyl-Tn. A novel mucin antigen associated with prognosis in colorectal cancer patients

Colon cancers typically produce mucin. However, it is not known whether tumor mucin plays a biological role in cancer cell behavior. To address this issue, the expression of a mucin-associated antigen, sialosyl-Tn, was examined by immunohistochemical study in 128 primary colorectal carcinoma specimens from 137 patients who underwent curative surgical resection. Antigen expression was correlated with disease-free and overall 5-year survival. Sialosyl-Tn antigen expression occurred in 112 (87.5%) tumors, and was independent of age, gender, tumor location, Dukes' stage, depth of invasion, degree of differentiation, and ploidy status. Survival at 5 years for patients with sialosyl-Tn-negative versus sialosyl-Tn-positive tumors was 100% versus 73% (P less than 0.05) and disease-free survival was 94% versus 73%, respectively (P = 0.12). Although more advanced Dukes' stage, deeper invasion, and aneuploidy were all associated with poorer overall 5-year survival, antigen-negative tumors within each of these groups had much better prognoses than antigen-positive tumors. Multivariate regression analysis revealed that tumor ploidy (P less than 0.001) and sialosyl-Tn expression (P less than 0.05) were the two variables of most importance for predicting both disease-free and overall survival. The authors conclude that sialosyl-Tn expression is an independent predictor of poor prognosis in colon cancer, and therefore suggest that qualitative mucin alterations may reflect important differences in the biological behavior of these neoplasms.