Gene delivery to Her-2Â + breast cancer cells using a two-component delivery system to achieve specificity

To improve specificity for Her-2 positive breast cancer cells, a two component delivery strategy is utilized. DNA is condensed with cationic polylysine (PL/DNA) which delivers DNA to the endosomes of both Her-2 positive and negative cells. Neutral Her-2 targeting liposomes carry a pore forming protein, Listeriolysin O (LLO), which leads to breakdown of endosomes and delivery of PL/DNA. Co-localization of the PL/DNA and LLO/liposomes occurs more frequently in endosomes of Her-2 positive cells, leading to selective gene expression.277