P>Objective To investigate the significance of zonula occludens-1(ZO-1) mRNA and protein expression in invasion and metastasis and prognosis of human gastric carcinomas. Methods Real-time qPCR and SP immunohistochemistry on tissue microarray were used to detect 52 cases of ZO-1 mRNA and 228 cases of protein expression in gastric cancer. Results In contrast to normal epithelium, 81.1% gastric carcinoma tissues showed different degrees of aberrant expression of ZO-1 from membrane translocated to cytoplasm. The ZO-1 aberrant degree in the mucosal layer of gastric carcinoma cells in the case of well-differentiated, invasiveness depth confined to muscularis, without lymph node metastasis and early gastric cancer was lower than those in poorly differentiated, invasiveness depth breakthrough to muscularis, with lymph node metastasis and progressed gastric cancer, respectively (EM>P/EM>0.05). The ZO-1 aberrant degree in the invasive front area of gastric adenocarcinoma cell was higher than that in mucosa, but in lymph node metastases lower than that in invasive front area (P0.05). Postoperative survival rate in case with ZO-1 aberrant expression in mucosal layer of gastric carcinoma was lower than that in ZO-1 normal expression(EM>P/EM>0.05). However, ZO-1 aSUP>+/SUP> mRNA expression between gastric adenocarcinomas in mucosal layer and normal gastric epithelial cells in their corresponding adjacent normal gastric mucosa was not significantly different. ZO-1 a+ mRNA expression in mucosal layer of gastric adenocarcinomas was not significantly correlated with age, sex, histological type, the invasive depth and status of lymph node metastasis. Conclusion ZO-1 aberrant expression involved in the progress of gastric adenocarcinoma, but ZO-1 mRNA expression was not significantly different. These results suggested that hot the change of ZO-1 mRNA quantity but the ZO-1 aberrant expression associated withcarcinog