Immunohistochemical Study of the Multidrug Resistant(MDR) Gene Expression in Gastric Carcinoma

Han, Jung Hee; Park, Byung Gon; Roh, Mi Sook; Hong, Sook Hee

Abstract

We performed immunohistochemical stain of p-glycoprotein using JSB-1 monoclonal antibody to study multidrug resistant(MDR) gene expression in 137 gastric tumor tissues obtained from 87gastric carcinoma patients. The incidence of p-glycoprotein expression was 60 of 87 cases(69%) and it was not correlated with age, sex, depth of tumor invasion, and lymph node metastasis, but was correlated with histologic type of gastric adenocarcinoma. The distribution of p-glycoprotein positive cells in the tumor tissue was diffuse in 34 cases(73.9%) and focal in 12 cases(26.1%), and the dominant staining patterns of p-glycoprotein in the tumor cells were cytoplasmic and golgi staining in 20 cases(43.5%) and 19 cases(41.3%), respectively, and 7 cases(15.2%) showed fine granules in the cytoplasm. The incidence of p-glyco-protein expression in the tumor tissue was higher in A and AB blood type patients who have A antigen than in 0 and B blood type patients. Cytoplasmic staining pattern was dominant in O and B blood types and golgi staining in A and AB blood type patients. Among 27 patients 'who received chemotherapy, partial remission was noted in 9 of 11 p-glyco-protein negative patients(81.8%) and no remission or progression of the tumor was seen in 9 of 16 p-glycoprotein positive patient(56.3%). The p-glycoprotein expression in gastric carcinoma had no direct correlation with known several prognostic factors of the gastric tumor except for histologic type, and it is supposed that p-glycoprotein detection in gastric tumor tissue by immunohisto-chemical stain is a good method for predicting the response of chemotherapy, especially in p-gly-coprotein negative cases.