Tyroserleutide-based gene vector for suppressing VEGF expression in cancer therapy

Area of Science:

• Biotechnology
• Nanomedicine
• Cancer Research

Background:

• Vascular endothelial growth factor (VEGF) plays a crucial role in tumor angiogenesis and growth.
• Effective gene delivery systems are needed to deliver therapeutic agents like small interfering RNA (siRNA) for cancer treatment.
• Current gene vectors often face challenges with efficiency, stability, and cytotoxicity.

Purpose of the Study:

• To construct and evaluate a novel gene delivery system for suppressing VEGF expression and inhibiting tumor growth.
• To synthesize and characterize a (tyrosyl-seryl-leucine)-polyethyleneimine-poly(ethylene glycol) (YSL-PEI-PEG) conjugate as a gene carrier.
• To assess the efficacy and safety of the YSL-PEI-PEG/siRNA complex for cancer therapy.

Main Methods:

• Construction of a small interfering RNA (siRNA) plasmid DNA (pYr-1.1-hU6-EGFP-siVEGF) targeting VEGF.
• Synthesis of a YSL-PEI-PEG conjugate as a gene delivery vector.
• Evaluation of DNA condensation capability, transfection efficiency, and cytotoxicity of the vector.
• In vitro assessment of cancer cell proliferation inhibition and in vivo evaluation of tumor growth suppression.

Main Results:

• YSL-PEI-PEG efficiently condensed plasmid DNA at a vector/DNA weight ratio > 2.
• The YSL-PEI-PEG vector demonstrated higher transfection efficiency and lower cytotoxicity compared to PEI 25 kDa.
• The gene delivery system effectively inhibited cancer cell proliferation in vitro and suppressed tumor growth in vivo.
• The PEGylation enhanced the stability of the complex in systemic circulation.

Conclusions:

• The YSL-PEI-PEG conjugate is a promising non-viral gene vector for delivering siRNA targeting VEGF.
• This novel gene delivery system exhibits significant potential for clinical applications in cancer therapy.
• The combination of therapeutic peptide and PEGylation enhances anti-cancer efficacy and vector stability.