Significance of Heat Shock Protein 70 and Sulphomucin Expression in Gastric Adenocarcinomas

ABSTRACT

BACKGROUND: The heat shock proteins (HSPs) are stress-responsive genes present in all species and play a major role in many cellular processes. These proteins are highly conserved molecules whose expression is induced in eukaryotic cells by a variety of environmental stresses. These proteins can also be expressed in virally transformed cells and cancer cells. Especially, HSP70 is found at a higher level in growing cells than in resting cells. Sulphomucin is secreted by immature foveolar cells of stomach and expressed in gastric adenocarcinomas. Also, it is known that the population of sulphomucin-producing cells increases with long-lasting stress. The purpose of this study was to determine HSP70 and sulphomucin expressions in gastric adenocarcinoma and the significance of expressions. METHODS: Thirty-one paraffin-embeded surgical specimens of gastric adenocarcinomas were obtained from April 1992 to March 1995 and were selected for analysis. The expressions of HSP70 and sulphomucin were analyzed by immunohistochemical staining with HSP70 monoclonal antibody and the Spicer (HID) method. RESULTS: The expressions of HSP70 and sulphomucin were positive in 13 (42%) cases and 11 (35%) cases, respectively. The expression of HSP70 correlated with neither clinopathological factors nor sulphomucin expression. There was a significant correlation not only between sulphomucin expression and histologic differentiation (p=0.001) but also between disease-free survival and sulphomucin expression. CONCLUSIONS: Sulphomucin expression in gastric adenocarcinoma may be useful as a prognostic factor of gastric adenocarcinomas.