Novel small peptides derived from VEGF 125-136 : potential drugs for radioactive diagnosis and therapy in A549 tumor-bearing nude mice

• Published in: Scientific reports Vol. 7; no. 1; p. 4278
• Main Authors: Zhang, Xiang, Feng, Shibin, Liu, Jie, Li, Qianwei, Zheng, Lei, Xie, Laiping, Li, Hongmin, Huang, Dingde
• Format: Journal Article
• Language: English
• Published: England 27.06.2017
• Subjects: Animals; Cell Line, Tumor; Disease Models, Animal; Humans; Male; Mice; Molecular Structure; Neoplasms - diagnosis; Neoplasms - drug therapy; Neoplasms - mortality; Neoplasms - pathology; Peptide Fragments - chemistry; Peptide Fragments - pharmacology; Protein Binding; Radioisotopes; Radiopharmaceuticals; Rhenium; Tissue Distribution; Tomography, Emission-Computed, Single-Photon; Vascular Endothelial Growth Factor A - chemistry; Xenograft Model Antitumor Assays

Vascular endothelial growth factor receptor (VEGFR) is a critical factor in tumor angiogenesis and has been considered a potential target for receptor-mediated radionuclide imaging and therapy. In this study, we identified two peptides (QKRKRKKSRKKH and RKRKRKKSRYIVLS) derived from VEGF that displayed high binding affinities to VEGFR and strong inhibition of A549 cell growth. Tc- and Re-labeled peptides displayed high labeling efficiency and favorable stability in saline and human plasma. At the cellular level, the radiolabeled peptides could bind with A549 cells and be internalized via the VEGFR-1-mediated pathway. Tc/ Re-labeled peptide was significantly accumulated at xenograft tumors, as observed with single-photon emission computed tomography (SPECT) planar imaging. Moreover, Re-labeled peptides significantly inhibited tumor growth, prolonged the survival time of the tumor-bearing nude mice and resulted in much more necrotic regions and apoptotic cells in the A549 xenograft tumors. These results demonstrated that these two peptides as candidate drugs for radionuclide imaging and tumor therapy.