Decreased Expression of p12(DOC-1) Is Associated with More Advanced Tumor Invasion in Human Gastric Cancer Tissues

Background/Aims: p12(DOC-1) is a well-known growth suppressor; however, its role in gastric carcinogenesis is still unclear. We investigated the expression of p12(DOC-1) in gastric cancer tissues and its possible correlation with p53 expression, and determined its clinical significance. Methods: Immunohistochemical staining using the tissue array method was performed on 180 human gastric carcinomas. The clinicopathological features and prognostic significance were analyzed. Results: Of the 180 tissue samples, p53 expression was positive in 85 (47.2%) and p12(DOC-1) expression was negative in 140 (77.8%). The negative expression of p12(DOC-1) was significantly associated with a more advanced depth of tumor invasion and stage (p < 0.05). No apparent correlation was found between p(DOC-1) and p53 expressions. The 5-year survival rate of the p12(DOC-1)-positive cases (53.7%) was higher than that of the pp12(DOC-1)-negative cases (39.3%); however, neither p12(DOC-1) nor p53 expression status had any statistically significant prognostic value. Multivariate analysis revealed that lymph node metastasis, distant metastasis, lymphatic invasion and perineural invasion were independent prognostic factors. Conclusions: This is the first report that suggests that pp12(DOC-1) may be involved in the development and progression of gastric cancer. Further studies are required to clarify its exact role in the mechanism of gastric carcinogenesis. Copyright (c) 2009 S. Karger AG, Basel