title: Tumor vascular targeted liposomal-bortezomib minimizes side effects and increases therapeutic activity in human neuroblastoma.
abstract: Neuroblastoma is a childhood cancer with poor long-term prognosis in advanced stages. A major aim in neuroblastoma therapy is to develop targeted drug delivery systems to ameliorate drug therapeutic index and efficacy. In this study, a novel bortezomib (BTZ) liposomal formulation was set-up and characterized. Since BTZ is freely permeable across the lipidic bilayer, an amino-lactose (LM) was synthesized as complexing agent to entrap BTZ inside the internal aqueous compartment of stealth liposomes. High encapsulation efficiency was achieved by a loading method based on the formation of boronic esters between the boronic acid moiety of BTZ and the hydroxyl groups of LM. Next, NGR peptides were linked to the liposome surface as a targeting-ligand for the tumor endothelial cell marker, aminopeptidase N. Liposomes were characterized for size, Z-potential, polydispersity index, drug content, and release. Lyophilization in the presence of cryoprotectants (trehalose, sucrose) was also examined in terms of particle size changes and drug leakage. BTZ was successfully loaded into non-targeted (SL[LM-BTZ]) and targeted (NGR-SL[LM-BTZ]) liposomes with an entrapment efficiency of about 68% and 57%, respectively. These nanoparticles were suitable for intravenous administration, presenting an average diameter of 170nm and narrow polydispersity. Therefore, orthotopic NB-bearing mice were treated with 1.0 or 1.5mg/kg of BTZ, either in free form or encapsulated into liposomes. BTZ loaded liposomes showed a significant reduction of drug systemic adverse effects with respect to free drug, even at the highest dose tested. Moreover, mice treated with 1.5mg/kg of NGR-SL[LM-BTZ] lived statistically longer than untreated mice (P=0.0018) and SL[LM-BTZ]-treated mice (P=0.0256). Our results demonstrate that the novel vascular targeted BTZ formulation is endowed with high therapeutic index and low toxicity, providing a new tool for future applications in neuroblastoma clinical studies.
authors.affiliation: Dept. for Life Quality Studies, Alma Mater Studiorum University of Bologna, 47921 Rimini, Italy.
authors.forename: Guendalina
authors.initials: G
authors.lastname: Zuccari
authors.affiliation: Dept. for Life Quality Studies, Alma Mater Studiorum University of Bologna, 47921 Rimini, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Milelli
authors.affiliation: Laboratory of Oncology, Istituto G. Gaslini, 16147 Genoa, Italy.
authors.forename: Fabio
authors.initials: F
authors.lastname: Pastorino
authors.affiliation: Laboratory of Oncology, Istituto G. Gaslini, 16147 Genoa, Italy.
authors.forename: Monica
authors.initials: M
authors.lastname: Loi
authors.affiliation: Core Facility, Istituto G. Gaslini, 16147 Genoa, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Petretto
authors.affiliation: Dept. for Life Quality Studies, Alma Mater Studiorum University of Bologna, 47921 Rimini, Italy.
authors.forename: Amelia
authors.initials: A
authors.lastname: Parise
authors.affiliation: Dept. Pharmacy and Biotechnology, Alma Mater Studiorum University of Bologna, 40068 Bologna, Italy.
authors.forename: Chiara
authors.initials: C
authors.lastname: Marchetti
authors.affiliation: Dept. Pharmacy and Biotechnology, Alma Mater Studiorum University of Bologna, 40068 Bologna, Italy.
authors.forename: Anna
authors.initials: A
authors.lastname: Minarini
authors.affiliation: Animal Facility, IRCCS Azienda Ospedaliera Universitaria San Martino-IST Istituto Nazionale per la Ricerca sul Cancro, 16132 Genoa, Italy.
authors.forename: Michele
authors.initials: M
authors.lastname: Cilli
authors.affiliation: Animal Facility, IRCCS Azienda Ospedaliera Universitaria San Martino-IST Istituto Nazionale per la Ricerca sul Cancro, 16132 Genoa, Italy.
authors.forename: Laura
authors.initials: L
authors.lastname: Emionite
authors.affiliation: Laboratory of Oncology, Istituto G. Gaslini, 16147 Genoa, Italy.
authors.forename: Daniela
authors.initials: D
authors.lastname: Di Paolo
authors.affiliation: Laboratory of Oncology, Istituto G. Gaslini, 16147 Genoa, Italy.
authors.forename: Chiara
authors.initials: C
authors.lastname: Brignole
authors.affiliation: Laboratory of Oncology, Istituto G. Gaslini, 16147 Genoa, Italy.
authors.forename: Francesca
authors.initials: F
authors.lastname: Piaggio
authors.affiliation: Laboratory of Oncology, Istituto G. Gaslini, 16147 Genoa, Italy.
authors.forename: Patrizia
authors.initials: P
authors.lastname: Perri
authors.affiliation: Dept. for Life Quality Studies, Alma Mater Studiorum University of Bologna, 47921 Rimini, Italy.
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Tumiatti
authors.affiliation: Laboratory of Oncology, Istituto G. Gaslini, 16147 Genoa, Italy.
authors.forename: Vito
authors.initials: V
authors.lastname: Pistoia
authors.affiliation: Laboratory of Oncology, Istituto G. Gaslini, 16147 Genoa, Italy.
authors.forename: Gabriella
authors.initials: G
authors.lastname: Pagnan
authors.affiliation: Laboratory of Oncology, Istituto G. Gaslini, 16147 Genoa, Italy. Electronic address: mircoponzoni@ospedale-gaslini.ge.it.
authors.forename: Mirco
authors.initials: M
authors.lastname: Ponzoni
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000008:administration & dosage*; D000069286:Bortezomib / Q000008:administration & dosage*; D045744:Cell Line, Tumor; D002626:Chemistry, Pharmaceutical; D004305:Dose-Response Relationship, Drug; D016503:Drug Delivery Systems / Q000379:methods*; D005260:Female; D006801:Humans; D008081:Liposomes; D051379:Mice; D008819:Mice, Nude; D009389:Neovascularization, Pathologic / Q000188:drug therapy* / Q000473:pathology; D009447:Neuroblastoma / Q000188:drug therapy* / Q000473:pathology; D023041:Xenograft Model Antitumor Assays / Q000379:methods
chemical_list: D000970:Antineoplastic Agents; D008081:Liposomes; D000069286:Bortezomib
keywords: Bortezomib; Neuroblastoma; Stealth liposomes; Targeted therapy; Vascular targeting