Targeting Breast Cancer Using Hyaluronic Acid-Conjugated Liposomes Triggered with Ultrasound

The successful targeting of tumors can be achieved by conjugating targeting moieties to nanoparticles. These modifications allow nannocarriers to achieve greater targeting specificity through binding to specific receptors overexpressed on the surface of the tumor cells. In this study, pegylated liposomes encapsulating the model drug/dye calcein and conjugated to hyaluronic acid (HA) molecules were successfully synthesized, and their ability to target HA receptors overexpressed on a breast cancer cell line was investigated in vitro. Low-frequency ultrasound (LFUS), applied at three different power densities (6.2, 9, and 10 mW/cm(2)) were used to trigger the release of the entrapped calcein. Both the control and HA-conjugated liposomes showed similar release profiles. HA conjugation to the liposomes resulted in a significant increase in calcein uptake by the breast cancer cell line MDA-MB-231 known for its CD44 (HA receptor) overexpression, while such an effect was not recorded with NIH-3T3, an embryonic mouse fibroblast, with low levels of CD44 expression. The application of low LFUS showed a significant enhancement of calcein uptake by MDA-MB-231 cells from our liposome compared to calcein uptake without cell exposure to ultrasound. These findings suggest that combining HA-conjugated liposomes with ultrasound is a promising drug delivery platform in breast cancer treatment.