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Memona Khan,* Khaoula Cherni,* Rawdha Dekhili, Jolanda Spadavecchia CNRS, UMR 7244, NBD-CSPBAT, Laboratory of Chemistry, Structures and Properties of Biomaterials and Therapeutic Agents University Paris 13, Sorbonne Paris Nord, Bobigny, France*These authors contributed equally to this workCorrespondence: Rawdha Dekhili; Jolanda Spadavecchia, Email rawdhadekhilichimiste@gmail.com; jolanda.spadavecchia@univ-paris13.fr; jolanda.spadavecchia@gmail.comIntroduction: The aim of this study is focused on the development of theranostic hybrid nanovectors based on gold-doxorubicin (DOX)-gemcitabine (GEM) complexes and their active targeting with Galectin-1 (Gal-1) as a promising therapeutic and prognostic marker in cancer.Methods: For this purpose, a gold salt (HAuCl4) interacts with antitumor drugs (DOX; GEM) by chelation and then stabilizes with dicarboxylic acid-terminated polyethylene glycol (PEG) as a biocompatible surfactant. The proposed methodology is fast and reproducible, and leads to the formation of a hybrid nanovector named GEM@DOX IN PEG-AuNPs, in which the chemo-biological stability was improved. All synthetic chemical products were evaluated using various spectroscopic techniques (Raman and UV–Vis spectroscopy) and transmission electron microscopy (TEM).Results: To conceive a therapeutic application, our hybrid nanovector (GEM@DOX IN PEG-AuNPs) was conjugated with the Galectin-1 protein (Gal-1) at different concentrations to predict and specifically recognize cancer cells. Gal-1 interacts with GEM@DOX in PEG-AuNPs, as shown by SPR and Raman measurements. We observed both dynamic variation in the plasmon position (SPR) and Raman band with Gal-1 concentration.Discussion: We identified that GEM grafted electrostatically onto DOX IN PEG-AuNPs assumes a better chemical conformation, in which the amino group (NH3+) reacts with the carboxylic (COO−) group of PEG diacide, whereas the ciclopenthanol group at position C-5’ reacts with NH3+ of DOX.Conclusion: This study opens further way in order to built “smart nanomedical devices” that could have a dual application as therapeutic and diagnostic in the field of nanomedicine and preclinical studies associated.Keywords: gold-complex, gemcitabine, doxorubicin, galectin-1 protein, Raman spectroscopy, nanovector, diagnostic, biomarkers

Photodynamic therapy (PDT) represents an emerging strategy to treat various malignancies, including colorectal cancer (CC), the third most common cancer type. This work presents an engineered M13 phage retargeted towards CC cells through pentavalent display of a disulfide-constrained peptide nonamer. The M13CC nanovector was conjugated with the photosensitizer Rose Bengal (RB), and the photodynamic anticancer effects of the resulting M13CC-RB bioconjugate were investigated on CC cells. We show that upon irradiation M13CC-RB is able to impair CC cell viability, and that this effect depends on i) photosensitizer concentration and ii) targeting efficiency towards CC cell lines, proving the specificity of the vector compared to unmodified M13 phage. We also demonstrate that M13CC-RB enhances generation and intracellular accumulation of reactive oxygen species (ROS) triggering CC cell death. To further investigate the anticancer potential of M13CC-RB, we performed PDT experiments on 3D CC spheroids, proving, for the first time, the ability of engineered M13 phage conjugates to deeply penetrate multicellular spheroids. Moreover, significant photodynamic effects, including spheroid disruption and cytotoxicity, were readily triggered at picomolar concentrations of the phage vector. Taken together, our results promote engineered M13 phages as promising nanovector platform for targeted photosensitization, paving the way to novel adjuvant approaches to fight CC malignancies. [ABSTRACT FROM AUTHOR]

The demand for next-generation multifunctional nanovectors, combining therapeutic effects with specific cellular targeting, has significantly grown during the last few years, pursuing less invasive therapy strategies. Polyphenol-conjugated silver nanoparticles (AgNPs) appear as potential multifunctional nanovectors, integrating the biorecognition capability and the antioxidant power of polyphenols, the antimicrobial activity of silver, and the drug delivery capability of NPs. We present a spectroscopic and microscopic investigation on polyphenol-synthesized AgNPs, selecting caffeic acid (CA) and catechol (CT) as model polyphenols and using them as reducing agents for the AgNP green synthesis, both in the presence and in the absence of a capping agent. We exploit the plasmonic properties of AgNPs to collect Surface-Enhanced Raman Scattering (SERS) spectra from the nanosized region next to the Ag surface and to characterize the molecular environment in the proximity of the NP, assessing the orientation and tunable deprotonation level of CA, depending on the synthesis conditions. Our results suggest that the SERS investigation of such nanovectors can provide crucial information for their perspective biomedical application. [ABSTRACT FROM AUTHOR]

Liver fibrosis (LF) is a pathological repair reaction caused by a chronic liver injury that affects the health of millions of people worldwide, progressing to life-threatening cirrhosis and liver cancer without timely intervention. Due to the complexity of LF pathology, multiple etiological characteristics, and the deposited extracellular matrix, traditional drugs cannot reach appropriate targets in a time-space matching way, thus decreasing the therapeutic effect. Nanoparticle drug delivery systems (NDDS) enable multidrug co-therapy and develop multifactor delivery strategies targeting pathological processes, showing great potential in LF therapy. Based on the pathogenesis and the current clinical treatment status of LF, we systematically elucidate the targeting mechanism of NDDS used in the treatment of LF. Subsequently, we focus on the progress of drug delivery applications for LF, including combined delivery for the liver fibrotic pathological environment, overcoming biological barriers, precise intracellular regulation, and intelligent responsive delivery for the liver fibrotic microenvironment. We hope that this review will inspire the rational design of NDDS for LF in the future in order to provide ideas and methods for promoting LF regression and cure.

The demand for next-generation multifunctional nanovectors, combining therapeutic effects with specific cellular targeting, has significantly grown during the last few years, pursuing less invasive therapy strategies. Polyphenol-conjugated silver nanoparticles (AgNPs) appear as potential multifunctional nanovectors, integrating the biorecognition capability and the antioxidant power of polyphenols, the antimicrobial activity of silver, and the drug delivery capability of NPs. We present a spectroscopic and microscopic investigation on polyphenol-synthesized AgNPs, selecting caffeic acid (CA) and catechol (CT) as model polyphenols and using them as reducing agents for the AgNP green synthesis, both in the presence and in the absence of a capping agent. We exploit the plasmonic properties of AgNPs to collect Surface-Enhanced Raman Scattering (SERS) spectra from the nanosized region next to the Ag surface and to characterize the molecular environment in the proximity of the NP, assessing the orientation and tunable deprotonation level of CA, depending on the synthesis conditions. Our results suggest that the SERS investigation of such nanovectors can provide crucial information for their perspective biomedical application.

Iron (Fe)‐rich colloids in the environment have a high surface reactivity and facilitate transport of oxyanions and trace metal cations in soil. This study was set up to help identify the soil properties that might affect the concentrations of colloidal Fe and its size distribution in pore waters of soils. The pore water was isolated by centrifugation from a collection of 97 topsoils with contrasting properties and land use. The total Fe concentration in the pore waters ranged between 0.2 and 26 μM (10th–90th percentile) and was largest at low soil solution calcium (Ca) and high dissolved organic carbon (DOC), indicating that enhanced colloidal stability determines total Fe in solution. The colloidal size distribution (<100 nm) of Fe in the pore waters of 11 soils was determined with flow field flow fractionation (FlFFF‐UV‐ICP‐MS), which yielded three different fractions that varied strikingly among soils. The smallest fraction (<5 nm) of Fe co‐eluted with high DOC and copper (Cu), suggesting mononuclear Fe‐organic carbon (OC) complexes. This fraction increased with an increasing DOC/Fe ratio in pore waters. The 5–50‐nm fraction of Fe prevailed in soils with >3.5% organic carbon (%OC), whereas the 50–100‐nm fraction was dominant in soils with low %OC content. This suggests that natural organic matter inhibits crystallization and growth of mineral Fe particles. The elemental ratios of mineral colloids (>5 nm) indicated the presence of clay minerals and Fe oxyhydroxides, which was confirmed by scanning electron microscopy (SEM) analysis. This study thus identified soil %OC and Ca in soil solution as the dominant factors predicting both the concentration and size of pore water Fe colloids, with the smallest and, potentially, most mobile Fe colloids occurring in OC‐rich soils. Highlights: Pore water iron concentrations in topsoils are governed by colloid stabilityFlow field flow fractionation analysis allows characterization of iron colloids in the low nanometre rangeIron colloid size and composition vary strikingly among soilsSmall iron colloids prevail in organic carbon‐rich soils due to colloid growth inhibition [ABSTRACT FROM AUTHOR]

Aim: To develop a novel nanovector for the delivery of genetic fragments and CRISPR/Cas9 systems in particular. Materials & methods: Vitamin D3-functionalized carbon dots (D/CDs) fabricated using one-step microwave-aided methods were characterized by different microscopic and spectroscopic techniques. The 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl tetrazolium bromide assay and flow cytometry were employed to determine the cell viability and transfection efficiency. Results: D/CDs transfected CRISPR plasmid in various cell lines with high efficiency while maintaining their remarkable efficacy at high serum concentration and low plasmid doses. They also showed great potential for the green fluorescent protein disruption by delivering two different types of CRISPR/Cas9 systems. Conclusion: Given their high efficiency and safety, D/CDs provide a versatile gene-delivery vector for clinical applications. [ABSTRACT FROM AUTHOR]

The purpose of this study was to design a polyamidoamine (PAMAM)-based nanovector for the efficient delivery of methotrexate to U87 glioma cells. To this end, 0–100% acetylated PAMAM dendrimers of the fourth generation were synthesized and evaluated using drug encapsulation measurements, molecular dynamics simulations, neurotoxicity assays and neuronal internalization experiments. The best system was tested as a nanovector for methotrexate delivery to U87 glioma cells. The authors found that 25% acetylated PAMAM dendrimers of the fourth-generation combine low intrinsic toxicity, large drug complexation capacity and efficient internalization into hippocampal neurons. Nanovector complexation enhances the cytotoxic response of methotrexate against U87 glioma cells compared with free drug solutions. In conclusion, 25% acetylated PAMAM dendrimers of the fourth-generation increase drug uptake by glioma cells and thereby act as efficient nanovectors for methotrexate delivery. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract The development of an efficient small interfering RNA (siRNA) delivery system has held scientists interest since the discovery of the RNA interference mechanism (RNAi). This strategy gives hope for the treatment of many severe diseases. Herein, we developed hybrid nanovectors able to deliver siRNA to triple negative breast cancer cells. The nanovectors are based on PEGylated superparamagnetic iron oxide nanoparticles (SPION) functionalized with gH625 peptide, chitosan and poly- l -arginine. Every component has a key role and specific function: SPION is the core scaffolding the nanovector; PEG participates in the colloidal stability and the immune stealthiness; gH625 peptide promotes the nanovector internalization into cancer cells; cationic polymers provide the siRNA protection and favor siRNA endosomal escape and delivery to cytosol. The formulation was optimized by varying the amount of each compound. The efficacy of the siRNA retention and protection were investigated in the presence of high concentration of serum. Optimized nanovectors show a high uptake by MDA-MB-231 cells. The resulting down regulation of GFP expression was 73 ± 3% with our nanovector compared to 59 ± 8% obtained with the siRNA-Oligofectamine™ complex in the same conditions. [ABSTRACT FROM AUTHOR]

Abstract: This paper focuses on the synthesis of novel metal‐drugs nanoparticles based onto gold‐gemcitabine complexes relevant for biomedical applications. Gold (HAuCl4) is mixed with antitumor compounds (gemcitabine (GEM)) and dicarboxylic acid–terminated polyethylene‐glycol (PEG), which plays a double role as surfactants and reducing agent. The proposed methodology is fast and reproducible and leads the formation of hybrid‐metal nanoflowers called GEM ION‐PEG‐AuNPs, in which drug solubility and efficiency are improved. The emerging role of GEM ION PEG‐AuNPs in the hyperthermic treatment was applied in pancreatic cancer cells under specific experimental conditions. For this purpose GEM ION‐PEG‐AuNPs are decorated with HIV‐1 Tat peptide, a potent trans‐activator of transcription from the viral promoter and is essential for viral replication containing an activation domain and a nucleic acid‐binding domain. All products are evaluated by various spectroscopic techniques (Raman and UV–vis) and transmission electron microscopy (TEM). This study, revealing an original chemical approach, will employ an important position in the field of nanomedicine, with novel perspectives that will be proposed for the development of new drugs and active targeting in cancer therapy. [ABSTRACT FROM AUTHOR]

Myocardial infarction (MI), known to be rapidly progressed and fatal, necessitates a timely and effective intervention particularly within golden 24 h. The crux is to develop a therapeutic agent that can early target the infarct site with integrated therapeutic capacity. Finding the AT 1 receptor being most over-expressed at 24 h after MI, we developed a nanovector (AT 1 -PEG-DGL) anchored with AT 1 targeting peptide, and simultaneously armed it with specific microRNA-1 inhibitor (AMO-1) to attenuate cardiomyocyte apoptosis. In vivo imaging after IV administration demonstrated that AT 1 -PEG-DGL quickly accumulated in the MI heart during the desired early period, significantly outperforming the control group without AT 1 targeting. Most importantly, a pronounced in-vivo anti-apoptosis effect was observed upon a single IV injection. Apoptotic cell death in the infarct border zone was significantly decreased and the myocardial infarct size was reduced by 64.1% as compared with that in MI control group, promising for early MI treatment. [ABSTRACT FROM AUTHOR]

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) induces apoptosis of cancer cells when bound to its cognate receptors, TRAIL-R1 and TRAIL-R2 (DR4 and DR5), without being toxic to healthy cells. Nanovectorized TRAIL (abbreviated as NPT) is 10 to 20 times more efficient than one of the most potent soluble TRAIL used in preclinical studies (His-TRAIL). To determine whether differences in affinity may account for NPT superiority, a thermodynamic study was undertaken to evaluate NPT versus TRAIL binding affinity to DR5. Docking calculations showed that TRAIL in homotrimer configuration was more stable than in heterotrimer, because of the presence of one Zn ion in its structure. Indeed, TRAIL trimers can have head-to-tail orientations when Zn is missing. Altogether these data suggest that TRAIL homotrimer structures are predominant in solution and then are grafted on NPT. When docked to DR5, NPT carrying TRAIL homotrimer leads to a more stable complex than TRAIL monomer-based NPT. To comfort these observations, the extracellular domain of DR5 was immobilized on a chromatographic support using an ' in situ' immobilization technique. The determination of the thermodynamic data (enthalpy ∆H° and entropy ∆S°*) of TRAIL and NPT binding to DR5 showed that the binding mechanism was pH dependent. The affinity of NPT to DR5 increased with pH, and the ionized energy was more important for NPT than for soluble TRAIL. Moreover, because of negative values of ∆H° and ∆S°* quantities, we demonstrated that van der Waals and hydrogen bonds governed the strong NPT-DR5 association for pH > 7.4 (as for TRAIL alone). Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Nanostructured materials have been widely studied concerning their potential biomedical applications, primarily to selectively carry specific drugs or molecules within a tissue or organ. In this context, boron nitride nanotubes (BNNTs) have generated considerable interest in the scientific community because of their unique properties, presenting good chemical inertness and high thermal stability. Among the many applications proposed for BNNTs in the biomedical field in recent years, the most important include their use as biosensors, nanovectors for the delivery of proteins, drugs, and genes. In the present study, BNNTs were synthesized, purified, and functionalized with glycol chitosan through a chemical process, yielding the BNNT-GC. The size of BNNT-GC was reduced using an ultrasound probe. Two samples with different sizes were selected for in vitro assays. The nanostructures were characterized by transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), thermal analysis (TGA), and dynamic light scattering (DLS). The in vitro assays MTT and neutral red (NR) were performed with NIH-3T3 and A549 cell lines and demonstrated that this material is not cytotoxic. Furthermore, the BNNT-GC was applied in gene transfection of plasmid pIRES containing a gene region that express a green fluorescent protein (GFP) in NIH-3T3 and A549 cell lines. The gene transfection was characterized by fluorescent protein produced in the cells and pictured by fluorescent microscopy. Our results suggest that BNNT-GC has moderate stability and presents great potential as a gene carrier agent in nonviral-based therapy, with low cytotoxicity and good transfection efficiency. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 103A: 2176-2185, 2015. [ABSTRACT FROM AUTHOR]

Background Diatomite is a natural porous biomaterial of sedimentary origin, formed by fragments of diatom siliceous skeletons, called “frustules”. Due to large availability in many areas of the world, chemical stability, and non-toxicity, these fossil structures have been widespread used in lot of industrial applications, such as food production, water extracting agent, production of cosmetics and pharmaceutics. However, diatomite is surprisingly still rarely used in biomedical applications. In this work, we exploit diatomite nanoparticles for small interfering ribonucleic acid (siRNA) transport inside human epidermoid cancer cells (H1355). Methods Morphology and composition of diatomite microfrustules (average size lower than 40 μm) are investigated by scanning electron microscopy equipped by energy dispersive X-ray spectroscopy, Fourier transform infrared analysis, and photoluminescence measurements. Nanometric porous particles (average size lower than 450 nm) are obtained by mechanical crushing, sonication, and filtering of micrometric frustules. siRNA bioconjugation is performed on both micrometric and nanometric fragments by silanization. Results In-vitro experiments show very low toxicity on exposure of the cells to diatomite nanoparticle concentration up to 300 μg/ml for 72 h. Confocal microscopy imaging performed on cancer cells incubated with siRNA conjugated nanoparticles demonstrates a cytoplasmatic localization of vectors. Gene silencing by delivered siRNA is also demonstrated. Conclusion Our studies endorse diatomite nanoparticles as non-toxic nanocarriers for siRNA transport in cancer cells. General significance siRNA is a powerful molecular tool for cancer treatment but its delivery is inefficient due to the difficulty to penetrate the cell membrane. siRNA-diatomite nanoconjugate may be well suited for delivery of therapeutic to cancer cells. [ABSTRACT FROM AUTHOR]

Small interfering RNAs (siRNA) are emerging as novel therapeutic agents, providing competent delivery systems that are available. Dendrimers, a special family of synthetic macromolecules, represent an exciting delivery platform by virtue of their well-defined dendritic structure and unique multivalency and cooperativity confined within a nanoscale volume. Here, we report a Dicer-substrate siRNA (dsiRNA) which, when delivered using a structurally flexible triethanolamine-core poly(amidoamine) dendrimer of generation 5 as the nanocarrier, gives rise to a much greater RNAi response than that produced with conventional siRNA. Further decoration of the dsiRNA/dendrimer complexes with a dual targeting peptide simultaneously promoted cancer cell targeting through interacting with integrins and cell penetration via the interaction with neuropilin-1 receptors, which led to improved gene silencing and anticancer activity. Altogether, our results disclosed here open a new avenue for therapeutic implementation of RNAi using dendrimer nanovector based targeted delivery. From the Clinical Editor This study demonstrates superior therapeutic properties of siRNA when combined with a dendrimer-based targeted nano-delivery system. Similar approaches may eventually gain clinical utility following additional studies determining safety and efficacy. [ABSTRACT FROM AUTHOR]

Aim: To validate a novel sustained delivery system of liposome nanocarriers for inner-ear therapy and to investigate the transport pathway for their delivery. Materials & methods: Liposome nanocarriers containing gadolinium-tetra-azacyclo-dodecane-tetra-acetic acid (LPS+Gd-DOTA) were developed for MRI tracking the in vitro release profile and for in vivo uptake studies. Results: Encapsulating Gd-DOTA did not modify the liposomes. The LPS+Gd-DOTA nanocarriers were slowly released from a miniature osmotic pump. The LPS+Gd-DOTA moved along the ossicular chain toward the oval window after an epitympanic injection, whereas they traveled directly to the round window after a mesotympanic injection. However, the round window membrane was the major pathway for the LPS+Gd-DOTA to enter the inner ear. LPS+Gd-DOTA were visualized on both sides of the cochlea within 6 days of in vivo delivery via the osmotic pump. Discussion: The novel sustained inner-ear delivery system induced liposome nanocarriers into the inner ear efficiently without causing obvious adverse effect. There is the potential of using the system to administrate therapeutics in treating inner-ear diseases in the clinic. Original submitted 25 April 2013; Revised submitted 3 September 2013 [ABSTRACT FROM AUTHOR]

Abstract: RNAi-based nucleic acid molecules have attracted considerable attention as compelling therapeutics providing safe and competent delivery systems are available. Dendrimers are emerging as appealing nanocarriers for nucleic acid delivery thanks to their unique well-defined architecture and the resulting cooperativity and multivalency confined within a nanostructure. The present review offers a brief overview of the structurally flexible triethanolamine-core poly(amidoamine) (PAMAM) dendrimers developed in our group as nanovectors for the delivery of RNAi therapeutics. Their excellent activity for delivering different RNAi therapeutics in various disease models in vitro and in vivo will be highlighted here. [Copyright &y& Elsevier]

Abstract: The proliferation of pulmonary arterial smooth muscle cells (PASMCs) is a key pathophysiological component of vascular remodeling in pulmonary arterial hypertension (PAH), an intractable disease, for which pharmacotherapy is limited and only slight improvement in survival outcomes have achieved over the past few decades. RNA interference provides a highly promising strategy to the treatment of this chronic lung disease, while efficient delivery of small interfering RNA (siRNA) remains a key challenge for the development of clinically acceptable siRNA therapeutics. With the aim to construct useful nanomedicines, the mammalian target of rapamycin (mTOR) siRNA was loaded into hybrid nanoparticles based on low molecular weight (Mw) polyethylenimine (PEI) and a pH-responsive cyclodextrin material (Ac-aCD) or poly(lactic-co-glycolic acid) (PLGA). This hybrid nanoplatform gave rise to desirable siRNA loading, and the payload release could be modulated by the hydrolysis characteristics of carrier materials. Fluorescence observation and flow cytometry quantification suggested that both Ac-aCD and PLGA nanovectors (NVs) may enter PASMCs under either normoxia or hypoxia conditions as well as in the presence of serum, with uptake and transfection efficiency significantly higher than those of cationic vectors such as PEI with Mw of 25 kDa (PEI25k) and Lipofectamine 2000 (Lipo 2k). Hybrid Ac-aCD or PLGA NV containing siRNA remarkably inhibited proliferation and activated apoptosis of hypoxic PASMCs, largely resulting from effective suppression of mTOR signaling as evidenced by significantly lowered expression of mTOR mRNA and phosphorylated protein. Moreover, these hybrid nanomedicines were more effective than commonly used cationic vectors like PEI25k and Lipo 2k, with respect to cell growth inhibition, apoptosis activation, and expression attenuation of mTOR mRNA and protein. Therefore, mTOR siRNA nanomedicines based on hybrid Ac-aCD or PLGA NV may be promising therapeutics for diseases related to hypoxic abnormal growth of PASMCs. [Copyright &y& Elsevier]

Abstract: Tumour targeting nanoparticles (NPs) have demonstrated great potential for enhancing anticancer drug delivery to tumour sites and for reducing the side effects of chemotherapy. However, many nanoparticulate delivery systems still lack efficient tumour accumulation. In this work, we present a porous silicon (PSi) nanovector functionalized with a tumour-homing peptide, which targets the mammary-derived growth inhibitor (MDGI) expressing cancer cells both in vitro and in vivo, thereby enhancing the accumulation of the NPs in the tumours. We demonstrated that the tumour homing peptide (herein designated as CooP) functionalized thermally hydrocarbonized PSi (THCPSi) NPs homed specifically to the subcutaneous MDGI-expressing xenograft tumours. The THCPSi-CooP NPs were stable in human plasma and their uptake by MDGI-expressing cancer cells measured by confocal microscopy and flow cytometry was significantly increased compared to the non-functionalized THCPSi NPs. After intravenous injections into nude mice bearing MDGI-expressing tumours, effective targeting was detected and THCPSi-CooP NPs showed ∼9-fold higher accumulation in the tumour site compared to the control THCPSi NPs. Accumulation of both NPs in the vital organs was negligible. [Copyright &y& Elsevier]

Abstract: Nanovectors hold substantial promise in abating the off-target effects of therapeutics by providing a means to selectively accumulate payloads at the target lesion, resulting in an increase in the therapeutic index. A sophisticated understanding of the factors that govern the degradation and release dynamics of these nanovectors is imperative to achieve these ambitious goals. In this work, we elucidate the relationship that exists between variations in pore size and the impact on the degradation, loading, and release of multistage nanovectors. Larger pored vectors displayed faster degradation and higher loading of nanoparticles, while exhibiting the slowest release rate. The degradation of these particles was characterized to occur in a multi-step progression where they initially decreased in size leaving the porous core isolated, while the pores gradually increased in size. Empirical loading and release studies of nanoparticles along with diffusion modeling revealed that this prolonged release was modulated by the penetration within the porous core of the vectors regulated by their pore size. [Copyright &y& Elsevier]

Abstract: Understanding how nanovectors transport DNA molecules through cell membranes is of great importance in gene therapy. In this paper, we systematically investigate the mechanism of cellular uptake of cationic polymeric nanovectors containing DNA molecules through dissipative particle dynamics simulations. Our results show that the property of polyelectrolyte chains grafted to nanovector and DNA molecules can have important impacts on the endocytosis. Interestingly, it is found that the nanovector can be fully taken up with proper number of DNA molecules on its surface. On the contrary, in the absence of DNA it may become harder to be totally engulfed. Since the adsorption number of DNA is related to external pH, the cellular uptake could exhibit pH-responsive behavior. Further, we also provide insights into the comparison of uptake behaviors between cancer and normal cells, and importantly, we find that the enhanced uptake of gene nanovectors may be an inherent property of cancer cells. The present study may give some significant suggestions on future nanovector design for gene delivery. [Copyright &y& Elsevier]

Structure, size, physicochemical properties and production strategies make many plant viruses ideal protein based nanoscaffolds, nanocontainers and nano-building blocks expected to deliver a multitude of applications in different fields such as biomedicine, pharmaceutical chemistry, separation science, catalytic chemistry, crop pest control and biomaterials science. Functionalization of viral nanoparticles through modification by design of their external and internal surfaces is essential to fully exploit the potentiality of these objects. In the present paper we describe the development of a plant derived multifunctional tool for nanobiotechnology based on Tomato bushy stunt virus. We demonstrate the ability of this system to remarkably sustain genetic modifications and in vitro chemical derivatizations of its outer surface, which resulted in the successful display of large chimeric peptides fusions and small chemical molecules, respectively. Moreover, we have defined physicochemical conditions for viral swelling and reversible viral pore gating that we have successfully employed for foreign molecules loading and retention in the inner cavity of this plant virus nanoparticles system. Finally, a production and purification strategy from Nicotiana benthamiana plants has been addressed and optimized. [ABSTRACT FROM AUTHOR]

Abstract: The absence of safe, efficient, cost-effective, and easily scalable delivery platforms is one of the most significant hurdles and critical issues that limit the bench to bedside translation of oligonucleotides-based therapeutics. Acid-labile materials are of special interest in developing nonviral vectors due to their capability of intracellularly delivering therapeutic payload. In this study, a nanovector was designed by integrating a pH-responsive cyclodextrin material and low molecular weight polyethylenimine (PEI). Antisense oligonucleotide (ASON) Bcl-xl could be encapsulated into this hybrid nanosystem with extremely high loading efficiency by a nanoemulsion technique. The developed pH-responsive ASON nanotherapeutics could be efficiently transfected into human lung adenocarcinoma cells in a time- and dose-dependent manner, resulting in effective cell growth inhibition, significant suppression on the expression of Bcl-xl mRNA/protein, and efficient cell apoptosis. Importantly, the new nanovector showed drastically higher efficacy and lower cytotoxicity when compared with PLGA-based counterpart and commonly used cationic vectors like branched PEI (25,000 Da) and Lipofectamine 2000. This pH-responsive hybrid nanosystem may serve as a safe and efficient nonviral vector that may find wide applications in gene therapy. [Copyright &y& Elsevier]

There is an emerging need both in pharmacology and within the biomedical industry to develop new tools to target intracellular mechanisms. The efficient delivery of functionally active proteins within cells is potentially a powerful research strategy, especially through the use of antibodies. In this work, we report on a nanovector for the efficient encapsulation and delivery of antibodies into live cells with no significant loss of cell viability or any deleterious effect on cell metabolic activity. This delivery system is based on poly[2-(methacryl-oytoxy)ethyl phosphorylcholine]-block-[2-(diisopropylamino)ethyl methacrylate] (PMPC-PDPA), a pH-sensitive diblock copolymer that self-assembles to form nanometer-sized vesicles, also known as polymersomes, at physiological pH. Polymersomes can successfully deliver relatively high antibody payloads within different types of live cells. We demonstrate that these antibodies can target their respective epitope showing immunolabeling of γ-tubulin, actin, Golgi protein, and the transcription factor NF-κB in live cells. Finally, we demonstrate that intracellular delivery of antibodies can control specific subcellular events, as well as modulate cell activity and proinflammatory processes. [ABSTRACT FROM AUTHOR]

Abstract: Success of synthetic interfering nucleic acids (siRNAs)-based therapy relies almost exclusively on effective, safe and preferably nanometric delivery systems which can be easily prepared, even at high concentrations. We prepared by chemical synthesis various self-assembling polymers to entrap siRNAs into stable polyplexes outside cells but with a disassembly potential upon sensing endosomal acidity. Our results revealed that pyridylthiourea-grafted polyethylenimine (πPΕΙ) followed the above-mentioned principles. It led to above 90% siRNA-mediated gene silencing in vitro on U87 cells at 10nM siRNA concentration and did not have a hemolytic activity. Assembly of siRNA/πPΕΙ at high concentration was then studied and 4.5% glucose solution, pH 6.0, yielded stable colloidal solutions with sizes slightly below 100nm for several hours. A single injection of these concentrated siRNA polyplexes into luciferase-expressing human glioblastoma tumors, which were subcutaneously xenografted into nude mice, led to a significant 30% siRNA-mediated luciferase gene silencing 4days post-injection. Our results altogether substantiate the potential of self-assembling cationic polymers with a pH-sensitive disassembly switch for siRNA delivery in vitro and also in vivo experiments. [Copyright &y& Elsevier]

Abstract: Target ligand folic acid (FA) and cell-penetrating peptide octaarginine (R8) were coupled with the gene vectors (PEI600-CyD, PC) composed of β-cyclodextrin (β-CyD) and low-molecular-weight polyethylenimine (PEI, Mw 600) to form nanovectors for highly efficient gene delivery to tumor cells. The resultant ternary nanocomplexes of FA-PC/R8-PC/pDNA produced excellent gene transfaction abilities in the folate receptor (FR)-positive tumor cells in vitro and in vivo. The FR-mediated endocytosis and the R8-mediated transmembrane functionality together contributed to the high transfection levels. This study provides a promising means to produce gene nanovectors for in vivo applications. [Copyright &y& Elsevier]

Abstract: Individualized medicine is the healthcare strategy that rebukes the idiomatic dogma of ‘losing sight of the forest for the trees’. We are entering a new era of healthcare where it is no longer acceptable to develop and market a drug that is effective for only 80% of the patient population. The emergence of “-omic” technologies (e.g. genomics, transcriptomics, proteomics, metabolomics) and advances in systems biology are magnifying the deficiencies of standardized therapy, which often provide little treatment latitude for accommodating patient physiologic idiosyncrasies. A personalized approach to medicine is not a novel concept. Ever since the scientific community began unraveling the mysteries of the genome, the promise of discarding generic treatment regimens in favor of patient-specific therapies became more feasible and realistic. One of the major scientific impediments of this movement towards personalized medicine has been the need for technological enablement. Nanotechnology is projected to play a critical role in patient-specific therapy; however, this transition will depend heavily upon the evolutionary development of a systems biology approach to clinical medicine based upon “-omic” technology analysis and integration. This manuscript provides a forward looking assessment of the promise of nanomedicine as it pertains to individualized medicine and establishes a technology “snapshot” of the current state of nano-based products over a vast array of clinical indications and range of patient specificity. Other issues such as market driven hurdles and regulatory compliance reform are anticipated to “self-correct” in accordance to scientific advancement and healthcare demand. These peripheral, non-scientific concerns are not addressed at length in this manuscript; however they do exist, and their impact to the paradigm shifting healthcare transformation towards individualized medicine will be critical for its success. [Copyright &y& Elsevier]

Abstract: The potential of C60-nanoparticles (Buckminster fullerenes) as contaminant carriers in aqueous systems was studied in a series of toxicity tests with algae (Pseudokirchneriella subcapitata) and crustaceans (Daphnia magna). Four common environmental contaminants (atrazine, methyl parathion, pentachlorophenol (PCP), and phenanthrene) were used as model compounds, representing different physico-chemical properties and toxic modes of action. The aggregates of nano-C60 formed over 2 months of stirring in water were mixed with model compounds 5 days prior to testing. Uptake and excretion of phenanthrene in 4-days-old D. magna was studied with and without addition of C60 in aqueous suspensions. It was found that 85% of the added phenanthrene sorbed to C60-aggregates >200nm whereas about 10% sorption was found for atrazine, methyl parathion, and pentachlorophenol. In algal tests, the presence of C60-aggregates increased the toxicity of phenanthrene with 60% and decreased toxicity of PCP about 1.9 times. Addition of C60-aggregates reduced the toxicity of PCP with 25% in tests with D. magna, whereas a more than 10 times increase in toxicity was observed for phenanthrene when results were expressed as water phase concentrations. Thus, results from both toxicity tests show that phenanthrene sorbed to C60-aggregates is available for the organisms. For atrazine and methyl parathion no statistically significant differences in toxicities could be observed in algal and daphnid tests as a result of the presence of C60-aggregates. In bioaccumulation studies with phenanthrene in D. magna it was found that the uptake of phenanthrene was faster when C60 was present in suspension and that a 1.7 times higher steady-state concentration was reached in the animals. However, a very fast clearance took place when animals were transferred to clean water resulting in no accumulation of phenanthrene. This study is the first to demonstrate the influence of C60-aggregates on aquatic toxicity and bioaccumulation of other environmentally relevant contaminants. The data provided underline that not only the inherent toxicity of manufactured nanoparticles, but also interactions with other compounds and characterisation of nanoparticles in aqueous suspension are of importance for risk assessment of nanomaterials. [Copyright &y& Elsevier]

Aim: To develop a novel nanovector for the delivery of genetic fragments and CRISPR/Cas9 systems in particular. Materials & methods: Vitamin D 3 -functionalized carbon dots (D/CDs) fabricated using one-step microwave-aided methods were characterized by different microscopic and spectroscopic techniques. The 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl tetrazolium bromide assay and flow cytometry were employed to determine the cell viability and transfection efficiency. Results: D/CDs transfected CRISPR plasmid in various cell lines with high efficiency while maintaining their remarkable efficacy at high serum concentration and low plasmid doses. They also showed great potential for the green fluorescent protein disruption by delivering two different types of CRISPR/Cas9 systems. Conclusion: Given their high efficiency and safety, D/CDs provide a versatile gene-delivery vector for clinical applications.

Poor prognosis of esophageal cancer is associated with limited clinical treatment efficacy and lack of targeted therapies. With advances in nanomedicine, nanoparticle drug delivery systems play increasingly important roles in tumor treatment by enabling the simultaneous delivery of multiple therapeutic agents. We here propose a novel nanovector for targeted combination gene therapy and chemotherapy in esophageal cancer. A novel lipid nanovector (EYLN) was designed to carry the chemotherapy drug doxorubicin (Dox) and small interfering RNA against the lipid anabolic metabolism gene LPCAT1 , which we previously showed to be significantly overexpressed in esophageal cancer tissues, and its interference inhibited the proliferation, invasion, and metastasis of esophageal cancer cells. This vector, EYLN-Dox/siLPCAT1, was further coated with leukocyte membranes to obtain mEYLNs-Dox/siLPCAT1. The particle size of the coated nanovector was approximately 136 nm, and the surface zeta potential was -21.18 mV. Compared with EYLNs-Dox/siLPCAT1, mEYLNs-Dox/siLPCAT1 were more easily internalized by esophageal cancer cells due to the LFA-1 highly expressed leukocyte membrane coating and showed significant inhibition of the proliferation, migration, and metastasis of esophageal cancer cells, along with their LPCAT1 expression, through more effective delivery of the drugs. Moreover, the nanovectors showed improved blood circulation time, tissue distribution, tumor targeting, and tumor suppression in a mouse model. Thus, combining chemo and gene therapy with this new nanodelivery system achieved greater therapeutic efficacy, providing a new strategy for the treatment of esophageal cancer.