Correlation between vascular endothelial growth factor, angiogenesis, and tumor-associated macrophages in invasive ductal breast carcinoma

Angiogenic and anti-angiogenic factors, secreted by tumor, inflammatory, and stromal cells play an important role in regulation of neovascularization. Among the most important of these is vascular endothelial growth factor (VEGF), a specific mitogen for endothelium, which increases vascular permeability and induces proteolytic enzymes necessary for vascular remodeling. Tumor-associated macrophages (TAMs) can express complex functions related to tumor biology, including growth, proliferative rate, stroma formation and dissolution, and neovascularization. The aim of this study was to define, using immunohistochemical analysis, the microvessel density (MVD), VEGF expression, and TAMs level in 97 human invasive ductal breast carcinomas not otherwise specified (NOS), investigate a possible relationship between them and then correlate their values with tumor grade, mitotic activity index (MAI), tumor size and lymph-node status. Statistical analysis showed a strong positive relationship between MVD and VEGF expression (P<0.001). Furthermore, both MVD and VEGF expression were significantly correlated with tumor grade and lymph-node status, and TAMs infiltration with MAI. TAM level showed a significant positive connection with VEGF expression and MVD. These in situ observations suggest that VEGF stimulates angiogenesis in human invasive ductal breast carcinoma NOS and attracts macrophages to the tumor locus, which then may be involved in angiogenesis promotion. The expression of this angiogenic molecule, and MVD and TAM level, can provide additional prognostic significance and help in the identification of patients who need postoperative adjuvant therapy.