To date, the translation of Au (III) complexes into chemotherapeutic agents has been hindered by their low stability under physiological conditions, a crucial parameter in drug development. In this study, we report an innovative four-step synthesis of a stable Au (III)-doxorubicin (DOX) complex, acting as a key constitutive component of doxorubicin-loaded PEG-coated nanoparticles (DOX IN-PEG-AuNPs). For therapeutic purposes, such AuNPs were then functionalized with the anti-Kv11.1 polyclonal antibody (pAb), which specifically recognizes the hERG1 channel that is overexpressed on the membrane of human pancreatic cancer cells. The nature of the interactions between DOX and Au (III) ions was probed by various analytical techniques (Raman spectroscopy, UV-vis, and (1)H NMR), which enabled studying the Au (III)-DOX interactions during AuNPs formation. The theoretical characterization of the vibrational bands and the electronic transitions of the Au (III)-DOX complex calculated through computational studies showed significant qualitative agreement with the experimental observations on AuNPs samples. Stability in physiological conditions and efficient drug loading (up to to 85 w/w %) were achieved, while drug release was strongly dependent on the structure of DOX IN-PEG-AuNPs and on the pH. Furthermore, the interactions among DOX, PEG, and Au (III) ions in DOX IN-PEG-AuNPs differed significantly from those found in polymer-modified AuNPs loaded with DOX by covalent linkage, referred to as DOX ON-PEG-AuNPs. In vitro experiments indeed demonstrated that such differences strongly influenced the therapeutic potential of AuNPs in pancreatic cancer treatment, with a significant increase of the DOX therapeutic index when complexed to Au (III) ions. Collectively, our study demonstrated that Au (III)-DOX complexes as building blocks of PEGylated AuNPs constitutes a promising approach to transform promising Au (III) complexes into real chemotherapeutic drugs for the treatment of pancreatic cancer.

International audienceThe main objective of this study was to optimize and characterize a drug delivery carrier for doxorubicin, intended to be intravenously administered, capable of improving the therapeutic index of the chemotherapeutic agent itself, and aimed at the treatment of pancreatic cancer. In light of this goal, we report a robust one-step method for the synthesis of dicarboxylic acid-terminated polyethylene glycol (PEG)-gold nanoparticles (AuNPs) and doxorubicin-loaded PEG-AuNPs, and their further antibody targeting (anti-Kv11.1 polyclonal antibody [pAb]). In in vitro proof-of-concept studies, we evaluated the influence of the nanocarrier and of the active targeting functionality on the anti-tumor efficacy of doxorubicin, with respect to its half-maximal effective concentration (EC50) and drug-triggered changes in the cell cycle. Our results demonstrated that the therapeutic efficacy of doxorubicin was positively influenced not only by the active targeting exploited through anti-Kv11.1-pAb but also by the drug coupling with a nanometer-sized delivery system, which indeed resulted in a 30-fold decrease of doxorubicin EC50, cell cycle blockage, and drug localization in the cell nuclei. The cell internalization pathway was strongly influenced by the active targeting of the Kv11.1 subunit of the human Ether-à-go-go related gene 1 (hERG1) channel aberrantly expressed on the membrane of pancreatic cancer cells. Targeted PEG-AuNPs were translocated into the lysosomes and were associated to an increased lysosomal function in PANC-1 cells. Additionally, doxorubicin release into an aqueous environment was almost negligible after 7 days, suggesting that drug release from PEG-AuNPs was triggered by enzymatic activity. Although preliminary, data gathered from this study have considerable potential in the application of safe-by-design nano-enabled drug-delivery systems (ie, nanomedicines) for the treatment of pancreatic cancer, a disease with a poor prognosis and one of the main current burdens of today’s health care bill of industrialized countries

Suspicion has been raised that high aspect ratio nanoparticles or nanofibers might possess asbestos-like pathogenicity. The pleural space is a specific target for disease in individuals exposed to asbestos and by implication of nanofibers. Pleural effects of fibers depends on fiber length, but the key threshold length beyond which adverse effects occur has never been identified till now because all asbestos and vitreous fiber samples are heterogeneously distributed in their length. Nanotechnology advantageously allows for highly defined length distribution of synthetically engineered fibers that enable for in-depth investigation of this threshold length. We utilized the ability to prepare silver nanofibers of five defined length classes to demonstrate a threshold fiber length for acute pleural inflammation. Nickel nanofibers and carbon nanotubes were then used to strengthen the relationship between fiber length and pleural inflammation. A method of intrapleural injection of nanofibers in female C57Bl/6 strain mice was used to deliver the fiber dose, and we then assessed the acute pleural inflammatory response. Chest wall sections were examined by light and scanning electron microscopy to identify areas of lesion; furthermore, cell-nanowires interaction on the mesothelial surface of the parietal pleura in vivo was investigated. Our results showed a clear threshold effect, demonstrating that fibers beyond 4 µm in length are pathogenic to the pleura. The identification of the threshold length for nanofiber-induced pathogenicity in the pleura has important implications for understanding the structure-toxicity relationship for asbestos-induced mesothelioma and consequent risk assessment with the aim to contribute to the engineering of synthetic nanofibers by the adoption of a benign-by-design approach.

The high global incidence of cancer is associated with high rates of mortality and morbidity worldwide. By taking advantage of the properties of matter at the nanoscale, nanomedicine promises to develop innovative drugs with greater efficacy and less side effects than standard therapies. Here, we discuss both clinically available anti-cancer nanomedicines and those en route to future clinical application. The properties, therapeutic value, advantages and limitations of these nanomedicine products are highlighted, with a focus on their increased performance versus conventional molecular anticancer therapies. The main regulatory challenges toward the translation of innovative, clinically effective nanotherapeutics are discussed, with a view to improving current approaches to the clinical management of cancer. Ultimately, it becomes clear that the critical steps for clinical translation of nanotherapeutics require further interdisciplinary and international effort, where the whole stakeholder community is involved from bench to bedside. From the Clinical Editor: Cancer is a leading cause of mortality worldwide and finding a cure remains the holy-grail for many researchers and clinicians. The advance in nanotechnology has enabled novel strategies to develop in terms of cancer diagnosis and therapy. In this concise review article, the authors described current capabilities in this field and outlined comparisons with existing drugs. The difficulties in bringing new drugs to the clinics were also discussed.

In the current paper, a new strategy for risk assessment of nanomaterials is described, which builds upon previous project outcomes and is developed within the FP7 NANoREG project. NANoREG has the aim to develop, for the long term, new testing strategies adapted to a high number of nanomaterials where many factors can affect their environmental and health impact. In the proposed risk assessment strategy, approaches for (Quantitative) Structure Activity Relationships ((Q)SARs), grouping and read-across are integrated and expanded to guide the user how to prioritise those nanomaterial applications that may lead to high risks for human health. Furthermore, those aspects of exposure, kinetics and hazard assessment that are most likely to be influenced by the nanospecific properties of the material under assessment are identified. These aspects are summarised in six elements, which play a key role in the strategy: exposure potential, dissolution, nanomaterial transformation, accumulation, genotoxicity and immunotoxicity. With the current approach it is possible to identify those situations where the use of nanospecific grouping, read-across and (Q)SAR tools is likely to become feasible in the future, and to point towards the generation of the type of data that is needed for scientific justification, which may lead to regulatory acceptance of nanospecific applications of these tools.

Amorphous silica nanoparticles (ASNP) can be synthetized via several processes, 2 of which are the thermal route (to yield pyrogenic silica) and the wet route from a solution containing silicate salts (to obtain precipitated, colloidal, mesoporous silica, or silica gel). Both methods of synthesis lead to ASNP that are applied as food additive (E551). Current food regulation does not require that production methods of additives are indicated on the product label, and, thus, the ASNP are listed without mentioning the production method. Recent results indicate, however, that pyrogenic ASNP are more cytotoxic than ASNP synthesized through the wet route. The present study was aimed at clarifying if 2 representative preparations of ASNP, NM-203 (pyrogenic) and NM-200 (precipitated), of comparable size, specific surface area, surface charge, and hydrodynamic radius in complete growth medium, had different effects on 2 murine macrophage cell lines (MH-S and RAW264.7 cells). Our results show that, when incubated in protein-rich fluids, NM-203 adsorbed on their surface more proteins than NM-200 and, once incubated with macrophages, elicited a greater oxidative stress, assessed from Hmox1 induction and ROS production. Flow cytometry and helium ion microscopy indicated that pyrogenic NM-203 interacted with macrophages more strongly than the precipitated NM-200 and triggered a more evident inflammatory response, evaluated with Nos2 induction, NO production and the secretion of TNF-α, IL-6 and IL-1β. Moreover, both ASNP synergized macrophage activation by bacterial lipopolysaccharide (LPS), with a higher effect observed for NM-203. In conclusion, the results presented here demonstrate that, compared to precipitated, pyrogenic ASNP exhibit enhanced interaction with serum proteins and cell membrane, and cause a larger oxidative stress and stronger proinflammatory effects in macrophages. Therefore, these 2 nanomaterials should not be considered biologically equivalent.

Evidence supports the advantages of inhalation over other drug-administration routes in the treatment of lung diseases, including cancer. Although data obtained from animal models and conventional in vitro cultures are informative, testing the efficacy of inhaled chemotherapeutic agents requires human-relevant preclinical tools. Such tools are currently unavailable. Here, we developed and characterized in vitro models for the efficacy testing of inhaled chemotherapeutic agents against non-small-cell lung cancer (NSCLC). These models recapitulated key elements of both the lung epithelium and the tumour tissue, namely the direct contact with the gas phase and the three-dimensional (3D) architecture. Our in vitro models were formed by growing, for the first time, human adenocarcinoma (A549) cells as multilayered mono-cultures at the Air-Liquid Interface (ALI). The in vitro models were tested for their response to four benchmarking chemotherapeutics, currently in use in clinics, demonstrating an increased resistance to these drugs as compared to sub-confluent monolayered 2D cell cultures. Chemoresistance was comparable to that detected in 3D hypoxic tumour spheroids. Being cultured in ALI conditions, the multilayered monocultures demonstrated to be compatible with testing drugs administered as a liquid aerosol by a clinical nebulizer, offering an advantage over 3D tumour spheroids. In conclusion, we demonstrated that our in vitro models provide new human-relevant tools allowing for the efficacy screening of inhaled anti-cancer drugs.

SWNTs produced by the HiPco technique were purchased from Unidym ® , Inc. (Lot no. R1912).Reagents and solvents were purchased as reagent-grade from Fisher Scientific Ireland Ltd, or Sigma-Aldrich Ireland and used without further purification.TGA analyses were performed on a PerkinElmer Thermogravimetric Analyzer Pyris 1 TGA. The method used for performing TGA measurements is as follows: 5 minute isothermal step at 30 °C (to S3 equilibrate the sample); heat from 30 °C to 100 °C at a rate of 10 °C min -1 ; 20 minute isothermal step at 100 °C (to ensure evaporation of the solvents); heat from 100 °C to 900 °C at a rate of 10 °C min -1 .FT-IR spectra were measured in the solid state on a PerkinElmer FT-IR Spectrometer Spectrum 100 with a universal ATR sampling accessory (diamond/ZnSe crystal). The spectra were recorded at 256 scans with a 4 cm -1 resolution.Micro-Raman scattering measurements were carried out at room temperature in the backscattering geometry using RENISHAW 1000 micro-Raman system equipped with a CCD camera and a Leica microscope. An 1800 lines mm -1 grating was used for all measurements, providing a spectral resolution of ~ 1 cm -1 . As an excitation source the He-Ne laser with 633 nm excitation with variable powers was used. Measurements were taken with 20 seconds of exposure time and 4 accumulations. The laser spot was focused on the sample surface using a 50x objective with short-focus working distance. Raman spectra were collected on numerous spots on the sample and recorded with Peltier cooled CCD camera.Only one spectrum was collected per spot. The intensity ratios I D /I G were obtained by taking the peak intensities after a baseline correction. The data were collected and analyzed with Renishaw Wire and GRAMS software.XPS measurements were performed in a VERSAPROBE PHI 5000 from Physical Electronics, equipped with a Monochromatic Al Kα X-Ray source with a highly focused beam size which can be selected from 10 µm to 300 µm. The energy resolution was 0.6 eV. For the compensation of built up charge on the sample surface during the measurements a dual beam charge neutralization composed of an electron gun (~1 eV) and the Argon Ion gun (≤10 eV) was used.UV-Vis Absorption spectra were recorded on a Perkin Elmer UV/Vis Spectrometer Lambda 35 after 1 cycle, with an interval of 1 nm, slit width of 2 nm and scan speed of 240 nm min -1 . Emission spectra were taken in a HORIBA Jobin Yvon Fluorolog-3 Spectrofluorometer equipped with a 450 xenon CV lamp after 1 cycle, with slit width of 10 nm and integration time 0.1 s.