Silk-based nanocomplexes with tumor-homing peptides for tumor-specific gene delivery.

Nanoscale complexes of recombinant silk molecules containing THPs with DNA are designed as less cytotoxic and highly target-specific gene carriers. Genetically engineered silk proteins containing poly(L-lysine) domains to interact with pDNA and the THP to bind to specific tumorigenic cells for target-specific pDNA delivery are prepared, followed by in vitro transfection into MDA-MB-435 melanoma cells, highly metastatic human breast tumor MDA-MB-231 cells, and non-tumorigenic MCF-10A breast epithelial cells. The silk/poly(L-lysine) block copolymer containing Lyp1 (ML-Lyp1) shows significant differences from silk/poly(L-lysine) block copolymer containing F3 (ML-F3) in cytotoxicity to MCF10A cells. ML-F3 is the most promising candidate for target delivery into tumorigenic cells.