Multiple genetic expression abnormalities in gastric cancer

Abstract

By means of LSAB and ABC techniques, the expressions of p53, c-erbB-2, EGFR and ras were examined on 75 cases of gastric cancer (GC) specimens. (1) The positive rate of p53, c-erbB-2, EGFR and ras expression was 41.3%, 18.7%, 61.3% and 46.7%, respectively. The early cases and the intestinal type cases of GC had higher p53 positive rates than those of the advanced and the diffuse type ones, respectively. Two of 4 cases of severe dysplasia lesions adjacent to carcinoma sites were positive. c-erbB-2 positive immunoreactivity was only localized in the cancer cells, and tissues adjacent to the carcinoma sites were negative. Higher frequencies of c-erbB-2 expression were found in the well-differentiated GC. Positive correlation was found between EGFR expression and degree of malignancy of GC. (2) No correlation was found between the expression of c-erbB-2 and EGFR. (3) The expression of ras correlated positively with EGFR expression, but negatively with c-erbB-2 (P < 0.05). (4) No correlation was found between the expression of p53 and other genes examined. The results demonstrate that many gene abnormalities are present in the process of gastrocarcinogenesis.