Expression of vascular endothelial growth factor, its receptor, and other angiogenic factors in human breast cancer.

Angiogenesis is essential for the growth and metastasis of solid tumors. In this study, we examined gene expression of vascular endothelial growth factor (VEGF); its receptor, flt-1; basic fibroblast growth factor; and transforming growth factors (TGFs) alpha and beta in 18 paired cases of human breast carcinomas and the adjacent nonneoplastic tissues. In all of the paired cases, VEGF expression was markedly increased in the carcinomas. In contrast, an insignificant difference was observed in the expression of flt-1, basic fibroblast growth factor, TGF-alpha, and TGF-beta between the malignant breast tissue and the nonneoplastic counterpart. Immunostaining showed variable VEGF positivity of the malignant cells, whereas the nonneoplastic breast epithelial cells were negative. The findings of this study suggest that VEGF is an important angiogenic factor in human breast cancer.