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Aberrant glycosylation occurs during development of gastric carcinomas. The initiation of mucin‐type O‐glycosylation is regulated by GalNAc‐T3 (UDP‐N‐acetylgalactosamine:polypeptide N‐acetyl‐galactosaminyltransferase‐3). However, the clinical significance of GalNAc‐T3 expression in human gastric carcinoma has not yet been demonstrated. In the present study, we investigated the relationship between immunohistochemical GalNAc‐T3 expression and various clinicopathologic factors, including prognosis, in 117 gastric carcinoma patients. Of 117 gastric carcinomas examined, 59 (50.4%) showed strong expression of GalNAc‐T3. Strong expression was detected in 38 of 59 (64.4%) differentiated type and in 21 of 58 (36.2%) undifferentiated gastric carcinomas, indicating that the expression of GalNAc‐T3 correlated significantly with tumor differentiation (P=0.0023, x2test). Overall 5‐year survival rate in patients with strong GalNAc‐T3 expression (71.0%) was significantly better than that of patients with weak expression (49.3%) (P=0.0197, log‐rank test). Multivariate analysis identified GalNAc‐T3 expression as an independent prognostic factor (P=0.0158, Cox proportional hazards model). Our data suggest that GalNAc‐T3 expression may be a useful marker for prognosis and differentiation of gastric carcinomas. (Cancer Sci 2003; 94: 32–36)

Tumor development usually is accompanied by alterations of O-glycosylation. Initial glycosylation of mucin-type, O-linked proteins is catalyzed by one of the UDP-GalNAc–polypeptide N-acetyl-galactosaminyl transferases, such as GalNAc-T3, which is expressed in adenocarcinoma cells. The authors investigated whether such expression influenced tumor differentiation or prognosis in patients with colorectal carcinoma. The expression of GalNAc-T3 was evaluated immunohistochemically in 106 paraffin embedded samples from surgically resected colorectal carcinomas and was related to patient and tumor characteristics. Western blot analysis was performed on seven samples of frozen tissue. Strong tumor expression of GalNAc-T3 predicted 5-year survival in patients with colorectal carcinoma (67.2% vs. 43.6% for weak expression; P = 0.017). GalNAc-T3 expression was not associated with age, gender, tumor size, tumor location, or disease stage but was related to histologic differentiation (P = 0.049) and depth of invasion (P = 0.031). Univariate analysis showed that strong GalNAc-T3 expression significantly enhanced the likelihood of survival. Multivariate Cox survival analysis identified enzyme expression as an independent prognostic factor that was second only to TNM stage. GalNAc-T3 expression is a novel and useful indicator of tumor differentiation, disease aggressiveness, and prognosis in patients with colorectal carcinoma. Cancer 2002;94:1939–46. © 2002 American Cancer Society. DOI 10.1002/cncr.10423

Abstract—Helicobacter pylori (H. pylori)is a pathogen responsible for chronic gastritis and peptic ulcer diseases. It colonises the gastric mucus layer and adheres to the gastric epithelial cell surface. As this adherence is the first step of infection, it is important to study the adherence mechanism. The aim of this study was to analyse the specific binding assay of H. pylorito HEp‐2 cells and three gastric phenotype cell lines, AGS, MKN‐45 and AZ‐521. H. pyloriNCTC 11637 grown on agar plates was harvested and used in experiments. H. pyloriwas inoculated to pre‐cultured cell monolayers. Adhered bacteria were labelled with an anti‐H. pyloriantibody and an FITC‐conjugated secondary antibody and quantified by using a fluorescent plate reader. Microbial adherence to HEp‐2 cells increased with incubation time and incubated concentration of H. pylori. No further increase was obtained with four or more hours of incubation or with a concentration of 4 × 107bacteria/well or more. Scatchard analysis revealed a linear plot and the Bmax value was 88.3. Similar adherence patterns were obtained when AGS, AZ‐521 and MKN‐45 cells were used for adherence assays, but they had a lower binding affinity than HEp‐2 cells and AZ‐521. MKN‐45 cells had less receptors than HEp‐2 and AGS cells. In conclusion, H. pyloriadhered to the cell surface could be quantified by this assay method. H. pyloriadhesion to cell surfaces has a single population of binding site and one type of binding site on HEp‐2, AGS, AZ‐521 and MKN‐45 cells.

The neutralization of depolymerized holothurian glycosaminoglycan (DHG), unfractionated heparin (UFH), and low-molecular-weight heparin (LMWH) by protamine sulfate (PS) or platelet factor 4 (PF4) was studied. In in vitro studies, the prolongation of thrombin clotting time (TCT) by these glycos-aminoglycans was completely neutralized by PS, whereas activated partial thromboplastin time (APTT) was relatively resistant to neutralization. In rats, prolongation of bleeding time by DHG was neutralized by PS with concomitant normalization of TCT ex vivo. Heparin-cofactor-II-dependent antithrombin activity of DHG or UFH was neutralized by PF4 at a high concentration to the same extent; however, prolongation of the APTT by DHG was more resistant to neutralization by PF4 at a physiological plasma level than that by UFH. In conclusion, since the prolongation of bleeding time by DHG was neutralized by PS with concomitant normalization of TCT, and since PF4 neutralized the antithrombin activity of DHG, these proteins may be useful as antidotes for DHG to prevent bleeding in case of an overdose.