Neda Zarei - Department of biotechnology, Shiraz University of Veterinary, Shiraz, Iran
Foroogh Nejatollahi - Recombinant Antibody Laboratory, Department of Immunology, Shiraz University of Medical Sciences, Shiraz, Iran
Foroogh Nejatollahi - Shiraz HIV/AIDS Research Center, Shiraz University of Medical Sciences, Shiraz, Iran

Frizzled family receptor 7 (Fzd7) is one of the 10 members of Frizzled family of receptors. It interacts with Wnt ligands to activate canonical wnt signaling, which function to turn on different downstream transcription factors essential for modulating cellular proliferation, polarity, and differentiation. Altered expression of Fzd7 receptor is associated with human breast cancer development and progression. A method of treating breast cancer through modulation of Fzd7 may involve the use of antibodies to antagonize Fzd7. ScFvs (single-chain fragment variable) have provided an alternative to full-length mAbs in diagnostic and therapeutic applications. In this study we intended to produce specific scFv antibodies against Fzd7 and investigate their effects on MDA-MB-231 breast cancer cell line. A phage antibody display library of scFv was used and selection of specific scFvs was performed by 4 rounds of panning process against an immunodominant epitope of Fzd7, followed by PCR and fingerprinting of the selected clones. ELISA was used to confirm the specificity of the clones. The effects of the selected scFv on breast cancer cell line were assessed by MTT assay. According to the results a specific scFv with the frequency of 35% was selected which produced positive ELISA with the corresponding epitope. A significant reduction (50%) on cell survival was observed in the test group. Due to unique properties of scFvs including human origin, high affinity and specificity, the specific anti-Fzd7 scFv selected in this study has the potential to be used for inhibiting the wnt signaling pathway in breast cancer cells.

Frizzled receptor, anti-Fzd7 scFv, Breast cancer