Strategic design to create HER2-targeting proteins with target-binding peptides immobilized on a fibronectin type III domain scaffold.
Wanaporn YimchuenTetsuya KadonosonoYumi OtaShinichi SatoMaika KitazawaTadashi ShiozawaTakahiro KuchimaruMasumi TakiYuji ItoHiroyuki NakamuraShinae Kizaka-KondohPublished in: RSC advances (2020)
Tumor-binding peptides such as human epidermal growth factor receptor 2 (HER2)-binding peptides are attractive therapeutic and diagnostic options for cancer. However, the HER2-binding peptides (HBPs) developed thus far are susceptible to proteolysis and lose their affinity to HER2 in vivo . In this report, a method to create a HER2-binding fluctuation-regulated affinity protein (HBP-FLAP) consisting of a fibronectin type III domain (FN3) scaffold with a structurally immobilized HBP is presented. HBPs were selected by phage-library screening and grafted onto FN3 to create FN3-HBPs, and the HBP-FLAP with the highest affinity (HBP sequence: YCAHNM) was identified after affinity maturation of the grafted HBP. HBP-FLAP containing the YCAHNM peptide showed increased proteolysis-resistance, binding to HER2 with a dissociation constant ( K D ) of 58 nM in ELISA and 287 nM in biolayer interferometry and specifically detects HER2-expressing cancer cells. In addition, HBP-FLAP clearly delineated HER2-expressing tumors with a half-life of 6 h after intravenous injection into tumor-bearing mice. FN3-based FLAP is an excellent platform for developing target-binding small proteins for clinical applications.
Keyphrases
- type iii
- epidermal growth factor receptor
- binding protein
- amino acid
- breast reconstruction
- dna binding
- endothelial cells
- photodynamic therapy
- type diabetes
- squamous cell carcinoma
- tyrosine kinase
- young adults
- advanced non small cell lung cancer
- mass spectrometry
- high resolution
- papillary thyroid
- insulin resistance
- skeletal muscle
- protein protein
- childhood cancer