title: Targeted doxorubicin delivery by chitosan-galactosylated modified polymer microbubbles to hepatocarcinoma cells.
abstract: Targeted drug delivery is a main issue in cancer treatment. Taking advantage of recently developed polyvinyl alcohol (PVA)-based microbubbles, which are characterized by chemical versatility of the polymeric surface thereby allowing coating with different ligands, we set up a strategy for the targeted delivery of the anticancer agent doxorubicin to hepatocarcinoma cells. Such microbubbles are exceptionally efficient ultrasound scatterers and thus represent also an option as potential ultrasound contrast agents. Moreover, the oscillation of microbubbles induced by ultrasound could contribute to favor the release of drugs allocated on shell. Specifically, PVA-based microbubbles were reacted with a galactosylated chitosan complex and loaded with doxorubicin to enable the localization and drug delivery to HepG2 hepatocarcinoma cells overexpressing asialoglycoprotein receptors. We demonstrated selectivity and greater bioadhesive properties of the functionalized microbubbles for tumor cells than to normal fibroblasts, which were influenced by the degree of galactosylation. The presence of galactosylated chitosan did not modify the rate of doxorubicin release from microbubbles, whichwas almost complete within 48h. Cellular uptake of doxorubicin loaded on functionalized microbubbles was higher in HepG2 than in normal fibroblasts, which do not over express the asialoglycoprotein receptors. In addition, doxorubicin loaded onto functionalized microbubbles fully retained its cytotoxic activity. Cells were also irradiated with ultrasound, immediately after exposure to microbubbles. An early enhancement of doxorubicin release and cellular drug uptake associated to a concomitant increase in cytotoxicity was observed in HepG2 cells. Overall, results of the study indicate that galactosylated chitosan microbubbles represent promising devices for the targeted delivery of antitumor agents to liver cancer cells.
authors.affiliation: Dipartimento di Oncologia Sperimentale e Medicina Molecolare, Fondazione IRCCS Istituto Nazionale dei Tumori, Via Amadeo 42, 20133 Milano, Italy. raffaella.villa@istitutotumori.mi.it
authors.forename: Raffaella
authors.initials: R
authors.lastname: Villa
authors.forename: Barbara
authors.initials: B
authors.lastname: Cerroni
authors.forename: Lucia
authors.initials: L
authors.lastname: Viganò
authors.forename: Silvia
authors.initials: S
authors.lastname: Margheritelli
authors.forename: Gabriella
authors.initials: G
authors.lastname: Abolafio
authors.forename: Letizia
authors.initials: L
authors.lastname: Oddo
authors.forename: Gaio
authors.initials: G
authors.lastname: Paradossi
authors.forename: Nadia
authors.initials: N
authors.lastname: Zaffaroni
mesh_terms: D000970:Antineoplastic Agents / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology*; D006528:Carcinoma, Hepatocellular / Q000188:drug therapy* / Q000473:pathology; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D048271:Chitosan / Q000737:chemistry; D004305:Dose-Response Relationship, Drug; D004317:Doxorubicin / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology*; D016503:Drug Delivery Systems; D004354:Drug Screening Assays, Antitumor; D005690:Galactose / Q000737:chemistry; D056945:Hep G2 Cells; D006801:Humans; D008113:Liver Neoplasms / Q000188:drug therapy* / Q000473:pathology; D045423:Microbubbles; D015394:Molecular Structure; D011108:Polymers / Q000737:chemistry; D013329:Structure-Activity Relationship
chemical_list: D000970:Antineoplastic Agents; D011108:Polymers; D004317:Doxorubicin; D048271:Chitosan; D005690:Galactose