Down-regulation of vascular endothelial growth factor expression by anti-Her2/neu single chain antibodies

Area of Science:

• Oncology
• Immunology
• Molecular Biology

Background:

• HER2/neu overexpression occurs in 25-30% of breast tumors.
• HER2/neu signaling promotes tumor angiogenesis via vascular endothelial growth factor (VEGF).

Purpose of the Study:

• To evaluate the anti-angiogenic potential of novel anti-HER2/neu single chain-Fv (scFv) antibodies.
• To assess the impact of these antibodies on VEGF expression in HER2/neu-positive breast cancer cells.

Main Methods:

• Panning a human scFv library against HER2/neu epitopes.
• Treating BT-474 breast cancer cells with anti-HER2/neu scFv antibodies.
• Quantifying VEGF gene transcript levels using quantitative real-time PCR.
• Analyzing VEGF protein expression via western blot.

Main Results:

• All three tested anti-HER2/neu scFv antibodies significantly inhibited VEGF expression.
• Inhibition of VEGF was observed at both the gene and protein levels.
• Combined treatment with the scFv antibodies also demonstrated anti-angiogenic effects.

Conclusions:

• Anti-HER2/neu recombinant antibodies show promise as anti-angiogenic agents.
• These antibodies could be a valuable therapeutic strategy for HER2-positive breast cancers by targeting angiogenesis.