R. Tomaszewska et al., An immunohistochemical study of the expression of bcl-2 and p53 oncoproteins in pancreatic intraepithelial neoplasia and pancreatic cancer, INT J PANCR, 26(3), 1999, pp. 163-171
Background. The bcl-2 and p53 gene deregulation is frequently involved in s
everal types of malignancies. The purpose of this study was to evaluate the
expression of bcl-2 and p53 genes in various types of pancreatic intraepit
helial proliferation and in pancreatic cancer and to answer the question of
whether they interact in the process of intraductal epithelial proliferati
on.
Methods. Immunohistochemical staining for p53 and bcl-2 was performed on pa
raffin embedded sections from 56 patients operated on for pancreatic carcin
oma, chronic pancreatitis, and other conditions.
Results. Pancreatic cancer in 100% of cases showed p53 expression and in 27
.7% bcl-2 expression. The p53 gene was expressed already in pancreatic intr
aductal neoplasia and its frequency was significantly rising with an increa
sing degree of hyperplasia. Normal epithelium of pancreatic ducts and ductu
les showed a high expression of bcl-2, which was decreasing in the process
of intraductal proliferation.
Conclusions. Pancreatic cancer is characterized by a high expression of p53
and a low expression of bcl-2, In pancreatic cancers and pancreatic intrae
pithelial neoplasia, there is an inverse relationship between the expressio
n of bcl-2 and p53, Malignant behavior of pancreatic cancer may be associat
ed with the phenotype bcl-2-/p53+.