Doxorubicin-loaded Nanocarriers Research Articles

The amount of dextran in PLGA nanocarriers modulates protein corona and promotes cell membrane damage.

Polymeric nanocarriers (NCs) are efficient vehicles to prevent drug unspecific biodistribution and increase the drug amounts delivered to tumor tissues. However, some toxicological aspects of NCs still lack a comprehensive assessment, such as their effects on cellular processes that lead to toxicity. We evaluate the interaction of poly(lactic-co-glycolic acid) (PLGA) NCs prepared using dextran (Dex) and Pluronic®-F127 as stabilizing agents with myocardial cells (H9C2), breast adenocarcinoma cells (MCF-7) and macrophages (RAW 264.7) to address the effect of Dex in PLGA NC formulations. By an emulsion diffusion method, doxorubicin-loaded NCs were prepared with no Dex (PLGA-DOX), 1% (w/v) Dex (Dex1/PLGA-DOX) and 5% (w/v) Dex (Dex5/PLGA-DOX). Uptake analyses revealed a significant reduction in Dex5/PLGA-DOX NC uptake by H9C2 and MCF-7, as in the case of Dex1/PLGA-DOX NCs in the absence of in vitro protein corona, revealing an effect of dextran concentration on the formation of protein corona. RAW 264.7 cells presented a greater uptake of Dex5/PLGA-DOX NCs than the other NCs likely because of receptor mediated endocytosis, since C-type lectins like SIGN-R1, mannose receptors and scavenger receptor type 1 that are expressed in RAW 264.7 can mediate Dex uptake. Despite the lower uptake, Dex5/PLGA-DOX NCs promote the generation of reactive oxygen species and oxidative membrane damage in MCF-7 and H9C2 even though cellular metabolic activity assessed by MTT was comparable among all the NCs. Our results highlight the importance of an in-depth investigation of the NC-cell interaction considering additional mechanisms of damage apart from metabolic variations, as nanoparticle-induced damage is not limited to imbalance in metabolic processes, but also associated with other mechanisms, e.g., membrane and DNA damage.

Fluorescence resonance energy transfer monitoring of pH-responsive doxorubicin release from carbon dots/aptamer functionalized magnetic mesoporous silica.

Aim: To develop a novel theranostic nanoplatform for simultaneous fluorescent monitoring and stimuli-triggered drug delivery. Materials & methods: Different microscopic and spectroscopic techniques were used for the characterization of nanocarriers. MCF-7 and human umbilical vein endothelial cell lines were cultured and treated with different doses of doxorubicin-loaded nanocarriers. The cell viability and drug release were studied using MTT assay and fluorescence microscopy. Results: Biocompatible and mono-disperse nanocarriers represent hollow and mesoporous structures with the calculated surface area of 552.83m2.g-1, high magnetic activity (12.6 emu.g-1), appropriate colloidal stability and high drug loading capacity (up to 61%). Conclusion: Taxane-based carbon dots act as the pH-responsive gatekeepers for the controlled release of doxorubicin into cancer cells and provide a fluorescence resonance energy transfer system for real-time monitoring of drug delivery.

Hyperbranched polyglycerol β-cyclodextrin as magnetic platform for optimization of doxorubicin cytotoxic effects on Saos-2 bone cancerous cell line

In recent years, cancer has become the most important human health problems in the world. To overcome these problems, chemotherapy as a treatment approach is widely used in cancer treatment. However, single chemotherapy have a toxic side effects without completely effectiveness. This study has focused on the mitigating of doxorubicin side effects by designing pH-sensitive magnetic hyperbranched β-cyclodextrin as a nano-sized drug carrier. The accuracy of samples preparation has been confirmed by several characterizations including FTIR, NMR, SEM, EDX, TEM, XRD, DLS and Zeta Potential tests. The hemolysis assay results have shown that synthesized nanocarrier is completely biocompatible and could be used in blood contacting applications. In this case, nanoparticles have a better release in acidic pH value. In-vitro studies including MTT assay uptake assay, DAPI staining and apoptosis assay by flow-cytometry have been carried out on Saos-2 cell line. It is concluded that a synthesized doxorubicin-loaded nanocarrier has more cytotoxicity than free doxorubicin after incubation time, showing its high potentiality for target doxorubicin delivery to Saos-2 cell line.

Theranostic α-Lactalbumin-Polymer-Based Nanocomposite as a Drug Delivery Carrier for Cancer Therapy.

A nanotheranostic system was developed using α-lactalbumin along with Fe3O4 nanoparticles as an magnetic resonance imaging (MRI) contrast agent for medical imaging and doxorubicin as the therapeutic agent. α-lactalbumin was precipitated and cross-linked using poly(ethylene glycol) and glutaraldehyde. Besides, polyethylenimine was applied to increase the number of amine groups during cross-linking between α-lactalbumin and Fe3O4 nanoparticles. Interestingly, 90% of the initial protein used for the coaggregation process was incorporated in the prepared 130 nm nanocomposites, which facilitated the 85% doxorubicin loading. Formation of pH-sensitive imine bonds between glutaraldehyde and amine groups on α-lactalbumin and polyethylenimine resulted in higher release of doxorubicin at acidic pHs and consequently development of a pH-sensitive nanocarrier. The designed nanocomposite was less immunogenic owing to stimulating the production of less amounts of C3a, C5a, platelet factor 4, glycoprotein IIb/IIIa, platelet-derived β-thromboglobulin, interleukin-6, and interleukin-1β compared to the free doxorubicin. Furthermore, 1000 μg/mL nanocomposite led to 0.2% hemolytic activity, much less than the 5% standard limit. The void nanocarrier induced no significant level of cytotoxicity in breast cancer and normal cells following 96 h incubation. The doxorubicin-loaded nanocomposite presented higher cytotoxicity, apoptosis induction, and doxorubicin uptake in cancer cells than free doxorubicin. Conversely, lower cytotoxicity, apoptosis induction, and doxorubicin uptake were observed in normal cells treated with the doxorubicin-loaded nanocarrier compared to free doxorubicin. In line with the results of in vitro experiments, in vivo studies on tumor-bearing mice showed more suppression of tumor growth by the doxorubicin-loaded nanocomposite compared to the free drug. Moreover, the pharmacokinetic study revealed slow release of doxorubicin from the nanocomposite. Besides, in vitro and in vivo MRI studies presented a higher r2/r1 ratio and comparable contrast to the commercially available DOTAREM, respectively. Our findings suggest that this new nanocomposite is a promising nanotheranostic system with promising potential for cancer therapy and diagnosis.

Assessment of doxorubicin delivery devices based on tailored bare polycaprolactone against glioblastoma

Bare polycaprolactones with controlled molar mass and dispersity were employed to manufacture biodegradable devices, which were applied for doxorubicin delivery in glioblastoma. Micro- and nanoscale devices were prepared by emulsion formation or by a combination of precipitation and hydrolysis. The carriers were characterized by scanning electron microscopy, dynamic light scattering techniques, thermogravimetric analysis and differential scanning calorimetry. The encapsulation parameters and drug-release profiles are discussed in order to evaluate the influence of different fundamental parameters, such as molar mass and dispersity value, pH, morphology or crystallinity, on the efficiency of the doxorubicin delivery systems. The ability of doxorubicin-loaded micro- and nanoscale devices to induce cellular toxicity in glioblastoma cells was also explored. A cell viability assay against C6 cells of doxorubicin-loaded nanocarriers showed higher cytotoxicity than doxorubicin-loaded microcarriers. In addition, doxorubicin-loaded nanocarriers also showed good antitumor profile in human tumoral cells and improved the security profile in relation to free doxorubicin in non-tumoral cells. Consistent with the assessment study described in this manuscript, the results provide a proof of concept for the suitability of the approach, based on bare polycaprolactone, to local controlled-sustained release of doxorubicin for the treatment of glioblastoma.

Magnetic Targeting and Delivery of Drug-Loaded SWCNTs Theranostic Nanoprobes to Lung Metastasis in Breast Cancer Animal Model: Noninvasive Monitoring Using Magnetic Resonance Imaging.

In this study, we aimed to develop novel therapeutic and diagnostic approaches by improving the targeting of doxorubicin-loaded single-walled carbon nanotubes (SWCNTs) to metastatic regions, and monitor their preferential homing and enhanced therapeutic effect using noninvasive free-breathing magnetic resonance imaging (MRI) and bioluminescence imaging. High-energy flexible magnets were specifically positioned over the metastatic tumor sites in the lungs. SWCNTs biodistribution, tumor progression, and subsequent treatment efficiency were assessed following administration of the magnetically attracted doxorubicin-loaded anti-CD105 conjugated nanocarriers. The use of high-energy magnets offered improved theranostic effect of doxorubicin-loaded nanocarriers, by magnetically targeting them towards metastatic tumor sites in the lungs. MRI allowed sensitive monitoring of nanocarriers biodistribution in the abdominal organs, their preferential homing towards the metastatic sites, and their enhanced therapeutic effect. Combination of noninvasive MRI to localize sensitively the tumor sites, with specific positioning of magnets that can enhance the magnetic targeting of nanocarriers, allowed increasing the treatment efficiency.

Host-Guest Interaction-Mediated Construction of Hydrogels and Nanovesicles for Drug Delivery.

Hand-in-hand or head-to-head: A novel naphthalimide derivative is successfully designed and synthesized, which can self-assemble to produce hydrogels. When injecting this compound into CB[8] solution, the nanovesicles are obtained with a narrow size distribution. The cytotoxicity assay confirms that doxorubicin-loaded nanocarriers show therapeutic effects to cancer cells.

Abstract 5620: Novel phage display-derived neuroblastoma-targeting peptides potentiate the effect of drug nanocarriers in preclinical settings.

Abstract Purpose: Molecular targeting of drug delivery nanocarriers is expected to improve their therapeutic index while decreasing their toxicity. The identification of novel peptide ligands specific for cells present in high-risk neuroblastoma, a childhood tumor mostly refractory to current therapies, is needed. Experimental design: We performed combined in vitro/ex-vivo phage display screenings on human neuroblastoma cell lines and on tumors derived from orthotopic mouse models of human neuroblastoma. Binding validation and homing in vivo of selected phage clones were tested by immunohistochemistry/immunofluorescent analyses. Cell association experiments in vitro with the corresponding synthetic biotin-labeled peptides were performed. In vitro cytotoxicity and in vivo tumor accumulation and therapeutic experiments were performed using peptide-targeted, doxorubicin-loaded, nanocarriers. Results: By designing proper subtractive protocols, we identified phage clones specific either for the primary tumor, its metastases, or for the stromal components. Globally, we isolated 121 phage-displayed neuroblastoma-binding peptides; of these, 26 bound the primary tumor, 15 the metastatic mass, 57 and 23 their respective microenvironments. Of these, five phage clones were further validated for their specific binding ex-vivo to biopsies from stage IV neuroblastoma patients and to neuroblastoma tumors derived from mice. All five clones also targeted tumor cells and vasculature in vivo when injected into neuroblastoma-bearing mice. Coupling of the corresponding targeting peptides with doxorubicin-loaded nanocarriers led to a significant inhibition in tumor volume and enhanced survival in preclinical neuroblastoma models. Conclusions: Our findings demonstrate that novel ligands of neuroblastoma-associated markers are functional in the design of nanocarriers with therapeutic efficacy paving the way to their clinical development. Citation Format: Monica Loi, Daniela Di Paolo, Marco Soster, Chiara Brignole, Alice Bartolini, Laura Emionite, Jessica Sun, Pamela Becherini, Flavio Curnis, Andrea Petretto, Monica Sani, Alessandro Gori, Claudio Gambini, Renato Longhi, Michele Cilli, Theresa M. Allen, Federico Bussolino, Wadih Arap, Renata Pasqualini, Angelo Corti, Mirco Ponzoni, Serena Marchiò, Fabio Pastorino. Novel phage display-derived neuroblastoma-targeting peptides potentiate the effect of drug nanocarriers in preclinical settings. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 5620. doi:10.1158/1538-7445.AM2013-5620

Folate-Receptor-Targeted Delivery of Doxorubicin Using Polyethylene Glycol-Functionalized Gold Nanoparticles

Doxorubicin-loaded nanocarriers were produced employing folate-modified polyethylene glycol (PEG)-functionalized gold nanoparticles for targeted delivery to positive folate-receptor cancer cells. Doxorubicin and folate were, respectively, conjugated to activated-folate and activated-PEG. The conjugates formed doxorubicin nanocarrier with an average size of 12 nm in diameter. The drug release response of functionalized gold nanoparticles was characterized by an initial rapid drug release followed by a controlled release. The doxorubicin nanocarriers showed higher cytotoxic effect on folate-receptor-positive cells (KB cells) than folate-receptor-negative cells (A549 cells). Cell viability in healthy cells (HFF cells) in drug-loaded nanoparticles was higher compared to free doxorubicin. These nanocarriers might offer a cancer therapy with high targeting efficiency and lower side effects.