Maspin, a
serine protease inhibitor related to the
serpin family, can suppress invasion and
metastasis of
malignancies. To clarify the role of
maspin in the genesis and progression of gastric
carcinomas, its expression pattern and level were studied by immunohistochemistry on tissue microarrays containing gastric
carcinoma (n = 237), normal gastric mucosa (n = 23), intestinal
metaplasia (n = 38), and
adenoma (n = 42); and the findings were compared with clinicopathological parameters. Furthermore,
maspin expression in the gastric
carcinoma cell lines (HCG-27, MKN28, and MKN45) was examined by immunohistochemistry and Western blotting. We found that cytoplasmic and nuclear
maspin expression paralleled each other (P < .05) and decreased from intestinal
metaplasia,
adenoma, and
carcinoma to normal gastric mucosa (P < .05). A significant positive association was noted with depth of invasion, lymphatic invasion,
lymph node metastasis, and TNM stage (P < .05) but not with sex or Lauren's classification (P > .05). Univariate and multivariate analyses indicated that expression of
maspin correlated negatively with cumulative patient survival in gastric
carcinoma (P < .05) but was not an independent factor in the prognosis. The 2 independent factors, depth of invasion and lymphatic invasion, influenced the relation between nuclear
maspin expression and survival, whereas only depth of invasion correlated with cytoplasmic
maspin. Our study indicated that
maspin expression experiences upregulation in gastric precancerous lesions and then slight downregulation with malignant transformation. High expression may paradoxically promote invasion and
metastasis of gastric
carcinomas and could be considered a good marker for the pathobiological behaviors of gastric
carcinomas.