Recent studies indicated that mast cells (MCs) are involved in the regulation of extracellular matrix degradation, immune response and tumor angiogenesis via releasing numerous bioactive substances such as pro-angiogenic factors, including vascular fibroblast growth factor-2 (FGF-2), platelet-derived growth factor (PDGF), vascular endothelial growth factor (VEGF), interleukin-6 (IL-6) and some non-classical pro-angiogenic factors, for example tryptase [7,8]. The gene discussed is VEGFA; the disease is neoplasm.