(332b) Anti-HER2/neu Liposomes for Triggered Content Release In Ovarian and Breast Cancer Cells

Solid tumors still account for the majority of cancer mortality. For such cases of advanced disease, nanometer-sized long-circulating drug delivery carriers could provide enhanced accumulation and retention of therapeutics at the tumor sites relative to normal organs, and, following internalization by cancer cells, they could increase drug bioavailability by triggered release of encapsulated contents.

In this work, we describe PEGylated anti-HER2/neu liposomes composed of rigid bilayer membranes containing only lamellar forming lipids that are triggered to form phase-separated domains in a pH-dependent manner resulting in fast and extensive content release. These liposomes were evaluated in serum supplemented media (60% v/v serum). Anti-HER2/neu liposomes with encapsulated fluorescent compounds were also evaluated for binding, internalization and content release in HER2/neu overexpressing ovarian cancer cells, and breast cancer cells, and were compared to compositions similar to FDA approved formulations. Our studies demonstrate the potential of the proposed liposomes as delivery carriers to increase the drug bioavailability in metastatic tumors.