RESUMO
OBJECTIVE: Gastric carcinoma can be divided into two main histological and clinical types: diffuse and intestinal. The aim of this study was to investigate the expression of neu/c-erbB-2 oncoprotein, epidermal growth factor receptor (EGFR), cathepsin D (catD), progesterone receptor (PR) and tumor-associated glycoprotein-72 (TAG-72) in gastric carcinoma of these histological types. METHOD: In this randomized, prospective study we analyzed 85 biopsy samples from patients with gastric adenocarcinoma. The control group consisted of 40 specimens from normal gastric mucosa. Neu oncoprotein and PR were determined by ELISA. CatD and TAG-72 were quantified with immunoradiometric (IRMA) methods, and EGFR were studied by radioimmunoassay (RIA). RESULTS: Neu, EGFR, catD and TAG-72 concentrations were higher in the tumoral group (p = 0.02, p = 0.00001, p = 0.002 and p = 0.007, respectively). In diffuse adenocarcinomas, catD and PR expression was increased (p = 0.01 and p = 0.04 respectively), whereas TAG-72 concentration, which correlated with neu (r = 0.57), was higher in the intestinal type (p = 0.04). No significant differences in EGFR and neu concentrations were seen between the two histological types. CONCLUSIONS: The higher PR and catD concentrations in diffuse adenocarcinomas, and the overexpression of TAG-72 in the intestinal type, support the existence of two modes of gastric carcinogenesis.
