[Expression of vascular endothelial growth factor and its receptor (Flt-1) in breast carcinoma].

Objective: To investigate the expression of vascular endothelial cell growth factor (VEGF) and its receptor (Flt-1) in breast carcinoma and the relationship of such expression with angiogenesis, tumor invasion and metastasis.

Methods: In situ hybridization and immunohistochemistry technique were used to test the expression of mRNA and protein expression of VEGF and flt-1 in 48 specimens of breast carcinoma. 48 specimens of tissues near cancer, 3 specimens of fibroadenoma of breast, and 3 specimens of normal breast were used as controls.

Results: VEGF mRNA and its protein were expressed highly in breast carcinoma cells with the positive rate of 75% and 70.8% respectively. There was almost no expression of VEGF in vascular endothelial cells. Flt-1 mRNA and its protein were expressed only in a small quantity in a few tumor cells. The amount of blood vessel positive in Fit-1 mRNA and its protein was (26 +/- 12) piece/0.72 mm(2) and (24 +/- 12) piece/0.72 mm(2) respectively. The microvascular density (MVD) was significantly greater in VEGF and Flt-1 higher expression groups than in lower groups (P < 0.01). Both VEGF expression and Flt-1 expression were well correlated with the histological grade and lymph node metastasis.

Conclusion: VEGF promotes angiogenesis by paracrining in breast carcinoma, and takes part in tumor invasion and lymph node metastasis. Test of the expression of VEGF and Flt-1 may act as a reliable index to determine angiogenesis, malignancy, invasion and metastasis. Blocking their secretion and effect may act as a new treatment for breast carcinoma.