Conjugated metallothionein-carbon-doxorubicin nanotransporter for targeted breast cancer therapy.

Metalothionein (MT) is a polypeptide of molecular weight in the range of 6-10 kDa. MT typically contains 60 to 68 amino acid residues. MT is characterized by its unique content of metal ions as well as its sulfur content. Higher MT levels were observed in proliferating cells. This fact demonstrates the importance of MT in the process of cellular regulation (relationship to cancer). The most widely used drug for patients with breast cancer metastases is an anthracycline antitumor antibiotic doxorubicin (DOX). However, the clinical use of DOX is limited by dose-related heart muscle damage (cardiomyopathy), more prevalent with increasing cumulative doses. For this reason, creation of novel pharmaceutical formulations based on using alternative methods as nanocarriers for targeted drug delivery to tumour cells is a crucial task in modern pharmacology. The aim of this work was to design a nanotechnological construct. The construct is designed as two separate nanotransporters. The nanotransporter (A) is formed by an antibody-modified AgNPs particle and a carbon nanotube with encapsulated DOX (AgNPs/Ab1/MWCNT/DOX/ODN1). The nanotransporter (B) is engineered with SPION particle modified with antibody and with bound MT (SPION/Ab2/MT/ODN2). Construct AgNPs/Ab1/MWCNT/DOX/ODN1-SPION/Ab2/MT/ODN2 is formed using an oligonucleotide anchor. Individual parts of the nanotransporter were studied using appropriate methods. The presence of MT was monitored electrochemically by Brdicka method in connection with the transfer technique (AdTSV). Characteristic MT signals RS2CO (-1.15 V), Cat1 (-1.25 V), Cat2 (-1.45 V), Cat3 (-1.75 V) were observed at accumulation time of 120s. SDS PAGE confirmed the presence of MT on SPION nanoparticles at sizes 7 to 15 kDa. The DOX signal was fluorometrically monitored (Em 590 nm, Ex 490 nm). AgNPs sizes ranged from 15-20 nm, and the SPION nanoparticles ranged from 20-50 nm. Additionally, used AgNPs nanoparticles exhibited significant antiproliferative activity (growth inhibition by 20-40%) on a model culture S. Cerevisiae. Created nanoconstruct A showed growth inhibition for S. Cerevisiae by more than 50%. The nanoconstruct after these various analysis shows a high potential as an anticancer drug and may be an innovative way how to deal with the breast cancer in a targeted therapy

Zinc-modified nanotransporter of doxorubicine for multi-targeted therapy of prostate cancer cells.

Target therapy for oncologic diseases presents a big challenge for advance nanomedicine. In our work, we focused on multi-target approach development. Designed nanotransporter is based on polysaccharide chitosan which allows formation of nanoparticles. These nanoparticles can bind metal ions, mainly zinc (moreover, zinc stabilizes chitosan structure). The estimated zinc concentration was approximately 1 nmol/g of chitosan. In addition, chitosan nanoparticle (cage) irreversibly binds therapeutics which could be applied for targeted therapy of malignant tumours. Designed chitosan structure (LMQ, 10 g) encapsulation efficiency for doxorubicin was 50%. The pH change (tested interval 5 - 8) caused 20% release of doxorubicin from the nanocage. The nanotransporter is orientated to cancer tissue due the fact that the malignant cells highly express metallothionein (MT). The increased affinity of MT to zinc ions causes that the nanotransporter is preferentially bound to tumour regions with a high MT concentration. Our latest experimental results showed the changes in amino acid metabolism of prostate cancer signalized by increase in the amount of amino acid sarcosine. Therefore, the chitosan-based nanotransporter was modified by anti-sarcosine antibody. The functionality of designed nanotransporter was proved by ELISA with double detection of doxorubicin using fluorescence and by peroxidase activity of ABTS substrate. In another system, magnetic separation and identification of individual components of the nanotransporter were used. The sarcosine binding activity was estimated around 50%

Tomographic capabilities of the new GEM based SXR diagnostic of WEST

International audienceThe tokamak WEST (Tungsten Environment in Steady-State Tokamak) will start operating by the end of 2016 as a test bed for the ITER divertor components in long pulse operation. In this context, radiative cooling of heavy impurities like tungsten (W) in the Soft X-ray (SXR) range [0.1 keV; 20 keV] is a critical issue for the plasma core performances. Thus reliable tools are required to monitor the local impurity density and avoid W accumulation. The WEST SXR diagnostic will be equipped with two new GEM (Gas Electron Multiplier) based poloidal cameras allowing to perform 2D tomographic reconstructions in tunable energy bands. In this paper tomographic capabilities of the Minimum Fisher Information (MFI) algorithm developed for Tore Supra and upgraded for WEST are investigated, in particular through a set of emissivity phantoms and the standard WEST scenario including reconstruction errors, influence of noise as well as computational time

Zinc-modified nanotransporter of doxorubicin for targeted prostate cancer delivery.

This work investigated the preparation of chitosan nanoparticles used as carriers for doxorubicin for targeted cancer delivery. Prepared nanocarriers were stabilized and functionalized via zinc ions incorporated into the chitosan nanoparticle backbone. We took the advantage of high expression of sarcosine in the prostate cancer cells. The prostate cancer targeting was mediated by the AntiSar antibodies decorated surface of the nanocage. Formation of the chitosan nanoparticles was determined using a ninhydrin assay and differential pulse voltammetry. Obtained results showed the strong effect of tripolyphosphine on the nanoparticle formation. The zinc ions affected strong chitosan backbone coiling both in inner and outer chitosan nanoparticle structure. Zinc electrochemical signal depended on the level of the complex formation and the potential shift from -960 to -950 mV. Formed complex is suitable for doxorubicin delivery. It was observed the 20% entrapment efficiency of doxorubicin and strong dependence of drug release after 120 min in the blood environment. The functionality of the designed nanotransporter was proven. The purposed determination showed linear dependence in the concentration range of Anti-sarcosine IgG labeled gold nanoparticles from 0 to 1000 µg/mL and the regression equation was found to be y = 3.8x - 66.7 and R2 = 0.99. Performed ELISA confirmed the ability of Anti-sarcosine IgG labeled chitosan nanoparticles with loaded doxorubicin to bind to the sarcosine molecule. Observed hemolytic activity of the nanotransporter was 40%. Inhibition activity of our proposed nanotransporter was evaluated to be 0% on the experimental model of S. cerevisiae. Anti-sarcosine IgG labeled chitosan nanoparticles, with loaded doxorubicin stabilized by Zn ions, are a perspective type of nanocarrier for targeted drug therapy managed by specific interaction with sarcosine and metallothionein for prostate cancer