Molecular Biological Characteristics of Differentiated Early Gastric Cancer on the Basis of Mucin Expression

ABSTRACT

BACKGROUND: It is clear that the biologic characteristics of gastric cancer are different on the basis of mucin phenotypes. However, there are unabated controversies on the exact biologic differences of mucin expression in gastric cancer. METHODS: We analyzed various protein expressions and microsatellite instability (MSI) status based on mucin expression in 130 differentiated early gastric adenocarcinoma cases. Furthermore, we evaluated the genomic alternation in 10 selected differentiated early gastric adenocarcinoma cases using array based comparative genomic hybridization (aCGH). RESULTS: Intestinal mucin predominant subtype showed significantly elevated p53 protein and caudal-related homeobox 2 expression, and delocalization of beta catenin expressions compared to the gastric mucin predominant subtype. On MSI status, the gastric mucin predominant subtype more frequently showed unstable status than the intestinal mucin predominant subtype. CGH study showed more frequent chromosomal gain and loss in the intestinal mucin predominant subtype than the gastric mucin predominant subtype, albeit without statistical significance. Interestingly, there were significant differences in chromosomal alternation between four mucin phenotypes. CONCLUSIONS: Study results suggest possible different points of biologic behaviors in early differentiated gastric adenocarcinomas by mucin expression type.