CD24 Expression in Gastric Adenocarcinoma Is Associated with Tumor Invasiveness

ABSTRACT

BACKGROUND: CD24, also referred to as the heat stable antigen in mice, is a glycosyl phosphatidylinositol- linked glycoprotein expressed by thymocytes, B cells, neutrophils and immature neuronal cells. It has been recently observed in a variety of human malignancy. Here, we demonstrated the expression of CD24 in gastric adenocarcinomas. METHODS: A total of 40 gastric adenocarcinomas and 20 tubular adenomas were immunohistochemically examined for the expression of CD24 and matrix metalloproteinase-2 (MMP-2) proteins. The immunoreactivity of CD24 was semiquantitatively scored (0, 1+, 2+) and compared with clinicopathologic variables and MMP-2 expression in tumor cells. RESULTS: CD24 was rarely expressed in normal gastric tissue and not expressed in tubular adenoma. In contrast, a moderate/strong expression (2+) of CD24 was observed in 25% of gastric adenocarcinomas, and 30% cases showed a weak CD24 staining (1+). Moreover, CD24 expression was significantly correlated with the depth of tumor invasion and MMP-2 expression. CONCLUSION: These results suggest that the aberrant expression of CD24 in gastric adenocarcinomas might be associated with tumor progression and invasiveness.