Ilaria Monaco

A Combined Approach Employing Chlorotoxin-Nanovectors and Low Dose Radiation To Reach Infiltrating Tumor Niches in Glioblastoma

Glioblastoma multiforme (GBM) is the most aggressive form of glioma, with life expectancy of around 2 years after diagnosis, due to recidivism and to the blood-brain barrier (BBB) limiting the amount of drugs which reach the residual malignant cells, thus contributing to the failure of chemotherapies. To bypass the obstacles imposed by the BBB, we investigated the use of nanotechnologies combined with radiotherapy, as a potential therapeutic strategy for GBM. We used poly(lactic-co-glycolic acid) (PLGA) nanoparticles (PNP) conjugated to chlorotoxin (CTX), a peptide reported to bind selectively to glioma cells. Silver nanoparticles were entrapped inside the functionalized nanoparticles (Ag-PNP-CTX), to allow detection and quantification of the cellular uptake by confocal microscopy, both in vitro and in vivo. In vitro experiments performed with different human glioblastoma cell lines showed higher cytoplasmic uptake of Ag-PNP-CTX, with respect to nonfunctionalized nanoparticles. In vivo experiments showed that Ag-NP-CTX efficiently targets the tumor, but are scarcely effective in crossing the blood brain barrier in the healthy brain, where dispersed metastatic cells are present. We show here that single whole brain X-ray irradiation, performed 20 h before nanoparticle injection, enhances the expression of the CTX targets, MMP-2 and ClC-3, and, through BBB permeabilization, potently increases the amount of internalized Ag-PNP-CTX even in dispersed cells, and generated an efficient antitumor synergistic effect able to inhibit in vivo tumor growth. Notably, the application of Ag-PNP-CTX to irradiated tumor cells decreases the extracellular activity of MMP-2. By targeting dispersed GBM cells and reducing MMP-2 activity, the combined use of CTX-nanovectors with radiotherapy may represent a promising therapeutic approach toward GBM.

Aptamer Functionalization of Nanosystems for Glioblastoma Targeting through the Blood–Brain Barrier

Polymeric nanoparticles (PNPs) may efficiently deliver in vivo therapeutics to tumors when conjugated to specific targeting agents. Gint4.T aptamer specifically recognizes platelet-derived growth factor receptor β and can cross the blood-brain barrier (BBB). We synthesized Gint4.T-conjugated PNPs able of high uptake into U87MG glioblastoma (GBM) cells and with astonishing EC50 value (38 pM) when loaded with a PI3K-mTOR inhibitor. We also demonstrated in vivo BBB passage and tumor accumulation in a GBM orthotopic model.

Synthesis of Lipophilic Core–Shell Fe3O4@SiO2@Au Nanoparticles and Polymeric Entrapment into Nanomicelles: A Novel Nanosystem for in Vivo Active Targeting and Magnetic Resonance–Photoacoustic Dual Imaging

In this work, iron/silica/gold core-shell nanoparticles (Fe3O4@SiO2@Au NPs) characterized by magnetic and optical properties have been synthesized to obtain a promising theranostic platform. To improve their biocompatibility, the obtained multilayer nanoparticles have been entrapped in polymeric micelles, decorated with folic acid moieties, and tested in vivo for photoacoustic and magnetic resonance imaging detection of ovarian cancer.

Gold nanorods and curcumin-loaded nanomicelles for efficient in vivo photothermal therapy of Barrett's esophagus

AIM Provide an enhanced local drug delivery, nanoparticle(s) to minimize systemic effects and achieve enhanced permeability and drug retention into abnormal cells and stroma. MATERIALS & METHODS Here a simultaneous loading of lipophilic gold nanorods (GNRs) and curcumin into polymeric nanomicelles made of biocompatible PLGA-b-PEG copolymer through a double re-emulsification process has been developed. RESULTS Initial results in vitro on Barretts esophagus and esophageal adenocarcinoma cell lines demonstrated a significant reduction in cell viability with curcumin and GNRs exposure (p < 0.05). In vivo Barretts-associated animal model confirmed these results with successful in vivo demonstrated eradication of all high-grade dysplastic premalignant cancer cells. CONCLUSION The synthesis of this novel nanosystem containing GNRs and curcumin is safe and effective in treating and eradicating premalignant esophageal adenocarcinoma.

Hard and soft nanoparticles for image-guided surgery in nanomedicine

Abstract The use of hard and/or soft nanoparticles for therapy, collectively called nanomedicine, has great potential in the battle against cancer. Major research efforts are underway in this area leading to development of new drug delivery approaches and imaging techniques. Despite this progress, the vast majority of patients who are affected by cancer today sadly still need surgical intervention, especially in the case of solid tumors. An important perspective for researchers is therefore to provide even more powerful tools to the surgeon for pre- and post-operative approaches. In this context, image-guided surgery, in combination with nanotechnology, opens a new strategy to win this battle. In this perspective, we will analyze and discuss the recent progress with nanoparticles of both metallic and biomaterial composition, and their use to develop powerful systems to be applied in image-guided surgery.

Hybrid cholesterol-based nanocarriers containing phosphorescent Ir complexes: in vitro imaging on glioblastoma cell line

Recently the use of phosphorescent heavy-metal complexes in bioimaging techniques has been a promising research field and has been attracted increasing interest. Among these, phosphorescent iridium(III) complexes have shown many photophysical characteristics that made them promising candidates for fluorescence probes. In this study an innovative copolymer consisting of cholesterol, a natural component of biological membranes, and the well-known biocompatible Polyethylene (PEG), has been synthesized. Cholesterol–PEG amphiphilic copolymer has been used to form novel nanocarriers characterized by the incorporation and/or linkage of the phosphorescent iridium(III) derivatives through covalent or non-covalent interactions. Finally the nanocarriers surface has been functionalized with the peptide chlorotoxin (Cltx), a targeting agent selective for glioblastoma cells (U87MG). The so obtained targeted water soluble nanocarrier has been tested for in vitro imaging on the glioblastoma cell line and has shown no toxic effect on cells.

One-pot synthesis of magnesium nanoparticles embedded in a chitosan microparticle matrix: a highly biocompatible tool for in vivo cancer treatment

A novel highly biocompatible nanosystem made up of a chitosan matrix and filled with magnesium nanoparticles was synthesized using a simple and one-pot strategy, and tested as a promising, well-tolerated tool for photothermal therapy. Moreover, in vivo a proof of concept on hepatocarcinoma-bearing mice is presented.

Controlled release of curcumin from curcumin-loaded nanomicelles to prevent peritendinous adhesion during Achilles tendon healing in rats.

We introduced curcumin-loaded nanomicelles into a tendon-healing model to evaluate their effects on tendon healing and adhesion. Three groups consisting of 36 rats underwent rupture and repair of the Achilles tendon. The treatment group received an injection of curcumin-loaded nanomicelles (gold nanorods [GNRs]-1/curcumin in polymeric nanomicelles [curc@PMs] at a dosage of 0.44 mg curcumin/kg in 0.1 mL saline) into the surgical site and exposed to laser postoperatively at weeks 1, 2, and 3, for three times 10 seconds each, on the surgical site in the rats that underwent tendon rupture and repair, while the other two groups received 0.44 mg curcumin/kg in 0.1 mL saline and 0.1 mL of saline, respectively. The specimens were harvested at 4 weeks and subjected to biomechanical and histological evaluation. The scoring results of tendon adhesion indicated that GNRs-1/curc@PMs group was in the lowest grade of peritendinous adhesions compared to the other groups. Histological assessment further confirmed the preventive effect of GNRs-1/curc@PMs on tendon adhesion. These findings indicated greater tendon strength with less adhesion in the group treated with GNRs-1/curc@PMs combined with laser exposure, and that nanoparticle-based therapy may be applied to prevent adhesion in clinical patients.

Phosphorescent iridium-containing nanomicelles: synthesis, characterization and preliminary applications in nanomedical imaging

Diagnostic nanomedicine constantly requires the development of novel contrast agents with intrinsic imaging capabilities. Phosphorescent Ir(III)-complexes represent good candidates when delivered through polymeric nanoparticles. In this work, we propose a biocompatible nanoparticle made from an intrinsically phosphorescent copolymer, synthesized directly with an imaging tag present on its backbone. Polymeric nanoparticles can be obtained with the exact amount of phosphorescent moieties needed to maximize their output signal. Complete characterization and ex vivo studies confirmed that this nanosystem is suitable as a future diagnostic tool.

Photoluminescent decoration of iron oxide magnetic nanoparticles for dual-imaging applications

A selective functionalization of dopamine amino group with the photoluminescent 7-nitroben-zofurazan was achieved through a one-pot protection-functionalization-deprotection sequence. The resulting fluorescent catecholic ligand was used as a capping agent for iron oxide nanoparticles thus obtaining photoluminescent magnetic nanoparticles (PL-MNPs). The PL-MNPs were then embedded into PLGA-b-PEG polymeric nanocarriers which quenched the emission of the capping agent. Full recovery of fluorescence was observed after disassembling the polymeric layer of the nanoparticle, thus supporting the use of PL-MNPs as a multifunctional system for targeted drug delivery.