Objective: To explore the expression of serine protease Omi/HtrA2 in gastric carcinoma tissue and its association with clinicopathological features and prognosis.
Methods: Omi/HtrA2 protein expression levels were detected by immunohistochemistry method in resected gastric carcinomas(n=68), adjacent noncancerous tissues(n=15), and normal tissues(n=15), and its association with clinicopathological features and prognosis were analyzed.
Results: Omi/HtrA2 expression was positive in 73.5%(50/68) of gastric cancer tissues, which was significantly higher than that in adjacent noncancerous tissues and normal tissues(P<0.05). There were no significant differences in Omi/HtrA2 expression with respect to sex, age, tumor size, and depth of invasion(all P>0.05). Omi/HtrA2 expression level was significantly associated with tumor differentiation, extent of lymph node metastasis, and tumor stage(all P<0.05). Overall 5-year survival rate of patients with gastric carcinoma was 63.3%. Five-year survival rate was higher in Omi/HtrA2 positive cases than Omi/HtrA2 negative cases(72.0% vs. 61.1%), however the difference was not statistically significant.
Conclusions: Omi/HtrA2 expression is more common in gastric carcinoma. Omi/HtrA2 expression is associated with tumor differentiation, extent of lymph node metastasis, and tumor stage.