Increased numbers of gastric-infiltrating mast cells and regulatory T cells are associated with tumor stage in gastric adenocarcinoma patients.

Mast cells (MCs) and regulatory T cells (Tregs) are the important components of the inflammatory infiltrating leukocytes in most malignant tumors. Our study was designed to investigate the infiltrating correlation between MCs and Tregs and clarify their prognostic significance in gastric cancer (GC). A total of 60 fresh GC tissues were collected and tumor-infiltrating leukocytes were isolated by gradient centrifugation. Tryptase and Foxp3 were used as markers for MCs and Tregs, respectively. The expression of tryptase and Foxp3 was determined in tumor-infiltrating leukocytes using flow cytometry. The expression of tryptase and Foxp3 were positively correlated. The increased infiltration of MCs correlated significantly with advanced stage of GC. The infiltration of MCs into the tumor may increase the number of Tregs. Tryptase is a promising marker to stratify GC patients into different risk groups.