TGFβ-1 regulation of VEGF production by breast cancer cells

Background: Angiogenesis is essential for tumor growth and metastasis. Vascular endothelial growth factor (VEGF) is the most potent angiogenic factor identified to date. TGFβ-1 acts as an indirect angiogenic agent. Methods: VEGF and TGFβ-1 were measured in the serum of breast cancer patients and agematched controls and in tumor tissue of cancer patients by ELISA. VEGF protein and mRNA expression by breast tumor cell lines were examined, and the effect of TGFβ-1 on VEGF production in these cells was assessed. Results: VEGF levels were significantly higher (P=.03) in the serum of patients with breast cancer compared to age-matched controls. A positive correlation was found between serum (r=0.539) and tumor tissue (r=0.688) levels of VEGF and TGFβ-1. Metastatic MDA-MB-231 breast cancer cells produce more VEGF than do the primary BT474 cells. TGFβ-1 significantly (P<.05) increased production of VEGF. Conclusions: Breast cancer cells constitutively produce VEGF protein and mRNA. There is a relationship between VEGF and TGFβ-1 levels in breast cancer patients, and TGFβ-1 regulates VEGF expression by breast cancer cells. Presented at the 50th Annual Cancer Symposium of the Society of Surgical Oncology, Chicago, Illinois, March 20–23, 1997.