Small molecular peptide-ScFv αvβ3 conjugates specifically inhibit lung cancer cell growth in vitro and in vivo.

Integrin αvβ3 (ITG) is highly expressed in various cancers and is considered a major target for anti-angiogensis cancer therapy. The single chain fragment variable of which (ScFv αvβ3) has been reported to inhibit tumor growth both in vitro and in vivo. Here, we conjugated cdGIGPQc which can exclusively bind to NSCLC cells according to our previous study synthesized by SPPS with ScFv αvβ3 expressed in E. coli BL21 (DE3) to develop a novel lung cancer specific targeted drug. Specific cell targeting of cdGIGPQc-ScFv was assessed in parallel with the single ScFv and a control nonspecific peptide-ScFv through immunofluorescence and flow cytometry while the αvβ3-binding property was examined by Western blot. Our results showed that cdGIGPQc-ScFv retained both the lung cancer-binding activity of cdGIGPQc and the antigen-recognizing ability of ScFv αvβ3 in vitro. CCK8 assays and in animal experiments suggested that cdGIGPQc-ScFv possessed a superior antitumor effect than ScFv and nonspecific peptide-ScFv both in vitro and vivo. Further immunohistochemical staining revealed that cdGIGPQc-ScFv retarded lung cancer growth through inhibiting tumor angiogensis and proliferation. Therefore, cdGIGPQc delivery of ScFv αvβ3 to lung cancer may be a hopeful new strategy for enhancing specific antitumor efficacy and cdGIGPQc-ScFv could be a potential drug for lung cancer targeted treatment.