Hyaluronic acid-coated liposomes for active targeting of gemcitabine

The aim of this work was the preparation, characterization, and preliminary evaluation of the targetingability toward pancreatic adenocarcinoma cells of liposomes containing the gemcitabine lipophilic prodrug[4-(N)-lauroyl-gemcitabine, C12GEM]. Hyaluronic acid (HA) was selected as targeting agent sinceit is biodegradable, biocompatible, and can be chemically modified and its cell surface receptor CD44is overexpressed on various tumors.For this purpose, conjugates between a phospholipid, the 1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine(DPPE), and HA of two different low molecular weights 4800 Da (12 disaccharidic units) and12,000 Da (32 disaccharidic units), were prepared, characterized, and introduced in the liposomes duringthe preparation.Different liposomal formulations were prepared and their characteristics were analyzed: size, Z potential,and TEM analyses underline a difference in the HA-liposomes from the non-HA ones. In order to betterunderstand the HA-liposome cellular localization and to evaluate their interaction with CD44receptor, confocal microscopy studies were performed. The results demonstrate that HA facilitates therecognition of liposomes by MiaPaCa2 cells (CD44+) and that the uptake increases with increase in thepolymer molecular weight.Finally, the cytotoxicity of the different preparations was evaluated and data show that incorporationof C12GEM increases their cytotoxic activity and that HA-liposomes inhibit cell growth more than plainliposomes.Altogether, the results demonstrate the specificity of C12GEM targeting toward CD44-overexpressingpancreatic adenocarcinoma cell line using HA as a ligand.