Maspin and p53 protein expression in gastric adenocarcinoma and its clinical applications

To investigate the role of maspin and p53 expression in the progression of gastric cancer, and its value as a prognostic indicator.

The expression of maspin and p53 in 152 cases of gastric cancer was detected by immunohistochemistry and compared with the clinicopathologic tumor parameters. The relationship between maspin and p53 expression was also analyzed in the gastric cancers.

The positive expression rates for maspin and p53 in the cancers were 71.7% (109 of 152 cases) and 56.6% (86 of 152 cases), respectively. Two patterns of immunostaining for maspin were seen in the maspin-positive gastric cancer cases: cytoplasm-only staining (67.0%, 73 of 109 cases) and staining of both cytoplasm and nucleus (33.0%, 36 of 109 cases). Maspin expression showed a negative association with histologic grade, depth of invasion, metastasis, and TNM stage (all P<0.05). p53 expression showed an association with node metastasis, and TNM stage (both P<0.05). Maspin expression was negatively correlated with p53 expression (P<0.001, r=-0.291). In univariate log-rank analysis, loss of maspin expression, histologic grade, distant metastasis, and TNM stage were associated with patient survival. Interestingly, patients with nuclear and cytoplasmic maspin expression survived longer than those with only cytoplasmic expression. However, in multivariate analysis TNM stage and regional node metastasis were the only independent prognostic factors.

Maspin expression might be an important factor in tumor progression and patient prognosis, but is not an independent prognostic factor. Maspin expression is inversely correlated with mutant p53 expression in gastric cancer, which suggests that maspin expression is regulated by the p53 pathway.