Immunohistochemical Analysis of HLA-DR and Secretory Component Expression in Gastric Adenocarcinoma

ABSTRACT

Sixty one cases of gastric adenocarcinoma were studied immunohistochemically for expression of HLA-DR and secretory component(SC) in order to analyze the relationship between expression of these in gastric cancer cells and the adjacent mucosa. Immunostaining was detected within the cytoplasm and on the cell memgrane. The rate of HLA-DR and SC expressions in cancer cells were 59.0% and 49.2%, respectively, and 52.5%/52.5% and 31.2%/50.8% the mucosa in adjacent/remote from the site of to cancer. The SC expression in the adjacent mucosa was lower than that of the remote mucosa(p=0.027). The HLA-DR expression in the cancer cells in the intestinal type of gastric adenocarcinoma(73.9%) was higher than that of the diffuse type(14.3%) and it was statistically significant(p=0.02). The presence of an increased amount of lymphoid infiltration in the gastric mucosa was closely related to the expression of HLA-DR and SC. Decreased or absent expression of SC at the transitional mucosal cells was possibly a result of exposure to genotoxic agents due to the lack of protective function of SC-IgA. From these results, one can postulate that the expression of HLA-DR and SC may play an important role in atleration in microenvironment with lymphoid infiltration.