Correlation of Mast Cell Densities, Angiogenesis and Vascular Endothelial Growth Factor in Proper Muscle Gastric...

There are increasing evidences that angiogenesis enhances tumor growth and biological aggressiveness in gastric carcinoma. Mast cells have been implicated in the angiogenic process, by secreting angiogenic factors including vascular endothelial growth factor (VEGF), or enzymes that degrade extracellular matrices. However, the exact nature of mast cells in relation to cancer is contradictory so we conducted retrospective studies, to find the significance of mast cell densities, and microvessel counts in each clinicopathologic factors, including VEGF expression, in proper muscle (PM) gastric carcinoma.

52 specimens, obtained from patients with PM gastric carcinoma, were studied using the immunohistochemical methods, monoclonal antibodies for mast cell tryptase, factor VIII-related antigen and VEGF.

Mast cell densities were significantly increased in diffuse histologic type (p=0.042), infiltrating margins (p<0.0001) and VEGF positive (p=0.010) tumors.Microvessel counts were significantly higher in patients over 55 years old (p=0.024), with tumor sizes larger than >3 cm (p=0.015), diffuse histologic type (p=0.038) and lymph node metastasis (p=0.001). Similarly there were significantly increased densities in VEGF positive tumors (p<0.0001). Pearson's correlation analysis revealed a significant relationship between mast cell densities and microvessel counts (r=0.614, p<0.01), indicating a high vascular grade with increased number of mast cells.

We demonstrated a close relationship between mast cell densities, microvessel counts and VEGF expression. These results suggest that mast cells and VEGF are important regulators of tumor angiogenesis and cooperatively induce the formation of vascular stroma in PM gastric carcinomas.