TGF beta-1 regulation of VEGF production by breast cancer cells.

Abstract

Angiogenesis is essential for tumor growth and metastasis. Vascular endothelial growth factor (VEGF) is the most potent angiogenic factor identified to date. TGF beta-1 acts as an indirect angiogenic agent. VEGF and TGF beta-1 were measured in the serum of breast cancer patients and age-matched 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 TGF beta-1 on VEGF production in these cells was assessed. 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 TGF beta-1. Metastatic MDA-MB-231 breast cancer cells produce more VEGF than do the primary BT474 cells. TGF beta-1 significantly (P < .05) increased production of VEGF. Breast cancer cells constitutively produce VEGF protein and mRNA. There is a relationship between VEGF and TGF beta-1 levels in breast cancer patients, and TGF beta-1 regulates VEGF expression by breast cancer cells.