RESUMO
OBJECTIVE: To explore the clinical significance of trefoil factor 1 (TFF1) protein expression and serum pepsinogen (PG) concentration in benign and malignant gastric ulcers. METHODS: The TFF1 protein expression was evaluated by immunohistochemistry in biopsies of gastric mucosa from 18 normal controls, 25 patients with gastric ulcer and 13 patients with ulcerative gastric cancer at our hospital during January to June 2011. The serum concentrations of PGI and PGII were detected by enzyme-linked immunosorbent assay (ELISA) and PG/PGII (PGR) was subsequently calculated. RESULTS: The expression of TFF1 protein increased significantly in ulcerative and peripheral gastric mucosa and peripheral mucosa of gastric cancers versus that in normal controls and the ulcerocancer group (3.04% ± 0.20%, 3.00% ± 0.20%, 3.23% ± 0.26% vs 1.67% ± 0.18%, 0.46% ± 0.18%, all P < 0.01). The elevated expression of TFF1 increased the risk of gastric ulcer (OR: 1.365, 95%CI: 1.065 - 1.749, P = 0.014) while the down-regulation of TFF1 significantly increased the risk of ulcerocancer (OR: 3.067, 95%CI: 1.391 - 6.757, P = 0.005). The serum levels of PGI and PGII in gastric ulcer group were significantly higher than that in normal control and ulcerocancer group ((150 ± 27), (28 ± 9) vs (121 ± 22), (17 ± 7), (79 ± 12), (20 ± 5) µg/L,all P < 0.01). The PGI level and PGR decreased significantly in the ulcerocancer group versus normal control (both P < 0.01). But there was no statistical difference in PGII (P > 0.05). Receiver operating characteristic curve analysis revealed that PGI and PGR were valuable for the diagnosis of malignant gastric cancer with an area under curve of 0.975 and 0.914 respectively. CONCLUSIONS: The expression of TFF1 protein increases in gastric ulcer but decreases in gastric ulcerocancer. The elevated serum levels of PGI and PGII indicate benign ulcer while a marked decline of serum PG I and PGR serves as a risk signal of malignant gastric ulcer. The evaluation of expression profiles of TFF1 protein and PGs is helpful for the differentiation of benign gastric ulcer from malignant ulcerocancer.