| Abstract: |
Background, bcl‐2 protooncogene encodes for a 26 kD protein effective in inhibiting programmed cell death (apoptosis). Its expression has been noted in lymphomas and colonic, lung, and breast carcinomas, bcl‐2 protein is believed to play a role in the gastric carcinogenic sequence where it has been demonstrated in dysplastic epithelium. To further study the role of bcl‐2 protein in gastric carcinogenesis and tumor progression, an immunohistochemical study of bcl‐2 expression in gastric adenocarcinomas and its relation to the histologic type, grade of differentiation, pT stage, lymph node status, and survival was performed. Methods. Immunohistochemical staining using monoclonal bcl‐2 protein antibody, clone 124, was performed on archival material. Results. Forty‐six of the sixty‐four adenocarcinomas (72%) showed bcl‐2 staining with immunoreactivity in 75% of the tumor or more. No specific pattern in the distribution of labeling was seen. bcl‐2 reactivity was significantly associated with adenocarcinomas of the intestinal morphotype. Forty‐five of 51 intestinal‐type tumors (88%) were immunoreactive versus only 1 of the “diffuse” tumors (7%) P = 0.001). Within the intestinal‐type adenocarcinomas, a trend of increasing prevalence of immunoreactivity with higher histologic grades was seen. No correlation between bcl‐2 expression and pT stage, lymph node status, or survival was observed. Conclusion. bcl‐2 expression in gastric adenocarcinoma appears to be associated almost exclusively with the intestinal morphotype and to some extent is more prevalent in grade 3 tumors. No correlation was noted with the pT stage, lymph node status, and survival. Inhibition of apoptosis through bcl‐2 protein expression appears to be specifically associated with promotion of intestinal‐type gastric adenocarcinoma but does not appear to be active and/or correlated with tumor progression. Copyright © 1995 American Cancer Society |
