%0 Journal Article
%T P53 and Rb tumor suppressor gene alterations in gastric cancer
%A Mattar
%A Rejane
%A Nonogaki
%A Suely
%A Silva
%A Cleonice
%A Alves
%A Venancio
%A Gama-Rodrigues
%A Joaquim J.
%J Revista do Hospital das Cl¨ªnicas
%D 2004
%I Scientific Electronic Library Online
%R 10.1590/S0041-87812004000400004
%X inactivation of tumor suppressor genes has been frequently observed in gastric carcinogenesis. our purpose was to study the involvement of p53, apc, dcc, and rb genes in gastric carcinoma. method: loss of heterozygosity of the p53, apc, dcc and rb genes was studied in 22 gastric cancer tissues using polymerase chain reaction; single-strand conformation polymorphism of the p53 gene exons 5-6 and exons 7-8 was studied using 35s-datp, and p53 expression was detected using a histological immunoperoxidase method with an anti-p53 clone. results and discussion: no loss of heterozygosity was observed in any of these tumor suppressor genes; homozygous deletion was detected in the rb gene in 23% (3/13) of the cases of intestinal-type gastric carcinoma. eighteen (81.8%) cases showed band mobility shifts in exons 5-6 and/or 7-8 of the p53 gene. the presence of the p53 protein was positive in gastric cancer cells in 14 cases (63.6%). normal gastric mucosa showed negative staining for p53; thus, the immunoreactivity was likely to represent mutant forms. the correlation of band mobility shift and the immunoreactivity to anti-p53 was not significant (p = .90). there was no correlation of gene alterations with the disease severity. conclusions: the inactivation of rb and p53 genes is involved in gastric carcinogenesis in our environment. loss of the rb gene observed only in the intestinal-type gastric cancer should be further evaluated in association with helicobacter pylori infection. the p53 gene was affected in both intestinal and diffuse histological types of gastric cancer.
%K gastric cancer
%K apc
%K dcc
%K rb
%K p53.
%U http://www.scielo.br/scielo.php?script=sci_abstract&pid=S0041-87812004000400004&lng=en&nrm=iso&tlng=en