Cationic RGD peptidomimetic nanoconjugates as effective tumor targeting gene delivery vectors with antimicrobial potential

Gene delivery combined with systemic targeting approach has shown promising potential in cancer gene therapy. Peptides are ideal functional motif for constructing biocompatible non-viral gene delivery vehicles. RGD peptides, in particular, are known to recognize the integrin alpha V beta(3), which is expressed specifically on angiogenic blood vessels and, therefore, is considered vital for anti-angiogenesis strategies and cancer treatment. In recent times, several RGD peptide-based non-viral gene delivery vectors have been utilized for targeted gene delivery, however, lack in proteolytic stability. In the current study, we have investigated a series of non-naturally modified RGD peptide mimic (M-OH) nanoconjugates with low molecular weight branched polyethylenimine (bPEI 1.8 kDa). The projected peptide mimic, Fmoc-FFARKA (M-OH), has already been demonstrated to have high binding efficiency for alpha V beta(3) integrins and enhanced cell adhesive ability with high stability compared to the natural RGD counterpart. The polymer-peptide, PEI-M-OH (PMOH), nanoconjugate vectors have been designed to enhance the tumor targeting ability, therapeutic proficiency, transfection efficiency and proteolytic stability. The synthesized nanoconjugates showed the ability to protect the bound DNA with low cytotoxicity and their pDNA complexes displayed enhanced transfection efficiency. Furthermore, a competitive study confirmed their selective behavior towards liver cancer cells, HepG2. Lastly, PMOH nanoconjugates also exerted significant antimicrobial effects against drug-resistant pathogens. Altogether, the data suggest that nanosized non-naturally modified RGD peptide mimic-based gene vectors hold great potential as efficient biomaterials for targeted gene delivery and antimicrobial applications.