Doxorubicin-loaded polypeptide nanorods based on electrostatic interactions for cancer therapy

Designing Molecularly Imprinted Polymer-Modified Boron-Doped Diamond Electrodes for Highly Selective Electrochemical Drug Sensors

Drug detection in biological solutions is essential in studying the pharmacokinetics of the body. Electrochemical detection is an accurate and rapid method, but measuring multiple drugs that react at similar potentials is challenging. Herein, we developed an electrochemical sensor using a boron-doped diamond (BDD) electrode modified with a molecularly imprinted polymer (MIP) to provide specificity in drug sensing. The MIP is a polymer material designed to recognize and capture template molecules, enabling the selective detection of target molecules. In this study, we selected the anticancer drug doxorubicin (DOX) as the template molecule. In the electrochemical measurements using an unmodified BDD, the DOX reduction was observed at approximately -0.5 V (vs Ag/AgCl). Other drugs, i.e., mitomycin C or clonazepam (CZP), also underwent a reduction reaction at a similar potential to that of DOX, when using the unmodified BDD, which rendered the accurate quantification of DOX in a mixture challenging. Similar measurements conducted in PBS using the MIP-BDD only resulted in a DOX reduction current, with no reduction reaction observed in the presence of mitomycin C and CZP. These results suggest that the MIP, whose template molecule is DOX, inhibits the reduction of other drugs on the electrode surface. Selective DOX measurement using the MIP-BDD was also possible in human plasma, and the respective limits of detection of DOX in PBS and human plasma were 32.10 and 16.61 nM. The MIP-BDD was durable for use in six repeated measurements, and MIP-BDD may be applicable as an electrochemical sensor for application in therapeutic drug monitoring.

Polypeptide-Based Systems: From Synthesis to Application in Drug Delivery

Synthetic polypeptides are biocompatible and biodegradable macromolecules whose composition and architecture can vary over a wide range. Their unique ability to form secondary structures, as well as different pathways of modification and biofunctionalization due to the diversity of amino acids, provide variation in the physicochemical and biological properties of polypeptide-containing materials. In this review article, we summarize the advances in the synthesis of polypeptides and their copolymers and the application of these systems for drug delivery in the form of (nano)particles or hydrogels. The issues, such as the diversity of polypeptide-containing (nano)particle types, the methods for their preparation and drug loading, as well as the influence of physicochemical characteristics on stability, degradability, cellular uptake, cytotoxicity, hemolysis, and immunogenicity of polypeptide-containing nanoparticles and their drug formulations, are comprehensively discussed. Finally, recent advances in the development of certain drug nanoformulations for peptides, proteins, gene delivery, cancer therapy, and antimicrobial and anti-inflammatory systems are summarized.

Anti-Biofouling Electrochemical Sensor Based on the Binary Nanocomposite of Silica Nanochannel Array and Graphene for Doxorubicin Detection in Human Serum and Urine Samples

A disposable and portable electrochemical sensor was fabricated by integrating vertically-ordered silica mesoporous films (VMSF) and electrochemically reduced graphene (ErGO) on a screen-printed carbon electrode (SPCE). Such VMSF/ErGO/SPCEs could be prepared by a simple and controllable electrochemical method. Stable growth of VMSF on SPCE could be accomplished by the introduction of an adhesive ErGO nanolayer owing to its oxygen-containing groups and two-dimensional (2D) planar structure. An outer VMSF layer acting as a protective coating is able to prevent the leakage of the inner ErGO layer from the SPCE surface. Thanks to the electrostatic permselectivity and anti-fouling capacity of VMSF and to the good electroactive activity of ErGO, binary nanocomposites of VMSF and ErGO endow the SPCE with excellent analytical performance, which could be used to quantitatively detect doxorubicin (DOX) in biological samples (human serum and urine) with high sensitivity, good long-term stability, and low sample amounts.

Chitosan-based DDSs for pH/hypoxia dual-triggered DOX delivery: Facile morphology modulation for higher in vitro cytotoxicity

The morphology of the drug delivery systems (DDSs) has been recognized to play an important role in their phagocytosis, cellular interaction and distribution. However, it is a technical challenge to simply prepare the non-spherical nanoscaled DDSs. Here, a facile strategy was developed to fabricate the pH/hypoxia dual-responsive nanowires by adding the maleic acid (MAH) and PEG modified chitosan (PEG-SS-CS-MAH) into aqueous solution of DOX. Compared with the PEG-SS-CS-MAH/DOX nanoparticles (NPs) by adding DOX into the PEG-SS-CS-MAH solution, the PEG-SS-CS-MAH/DOX nanowires (NWs) possessed a higher drug loading capacity of 58% and better pH/hypoxia dual-triggered DOX release performance with higher drug release in the simulated tumor intracellular microenvironment but a much lower premature drug leakage in the simulated normal physiological medium. As a result, higher in vitro anti-tumor efficacy was achieved with the PEG-SS-CS-MAH/DOX NWs, demonstrating their promising potential for tumor chemotherapy.

Two-step fabricating micelle-like nanoparticles of cisplatin with the 'real' long circulation and high bioavailability for cancer therapy

Cisplatin is a widely used anticancer drug for various solid tumors. However, the serious adverse effects caused by systemic distribution limit its wide use. In this study, we intend to use biocompatible materials polyethyleneimine (PEI) and poly(L-glutamic acid)-g-methoxy poly(ethylene glycol) (PLG-g-PEG) to construct nanoparticles to enhance the efficacy of cisplatin and reduce its side effects. The micelle-like nanoparticles were fabricated by a simple two-step method, with a core consisting of PEI and cisplatin and a PLG-g-mPEG coating layer. The obtained nanoparticles have a small particle size (41.79 nm) and high drug loading (16.43%). The coated nanoparticles (NP-II) strengthened the structure of PEI and cisplatin complex (NP-I) and slowed the drug release for less than 20% at pH 7.4 PBS in 24 h. Therefore, it could effectively inhibit the binding of free drug and plasma proteins to achieve the long circulation, and the bioavailability could be increased to about 600% and 285% of cisplatin solution and NP-I respectively. Besides, the cellular uptake of NP-II was enhanced in the acidic tumor microenvironment due to the detachment of coating layer and the increase of positive zeta potential of nanoparticles, which was benefit to reduce the side effect of cisplatin to normal cells. In vivo pharmacodynamic experiments also showed that NP-II improved the efficacy and reduced side effects compared to the cisplatin solution. In conclusion, the two-step fabricating micelle-like nanoparticles with the improved therapeutic efficiency and reduced side effects show great potential for cancer chemotherapy.

Acid-sensitive charge-reversal co-assembled polyurethane nanomicelles as drug delivery carriers

In order to obtain drug delivery carriers with good stability in blood and high cellular uptake efficiency, carboxyl groups and tertiary amine groups were respectively introduced into polyurethane to synthesize two kinds of amphiphilic polyurethanes with opposite charges (PUC and PUN). Their structures were characterized by Fourier transform infrared (FTIR) spectroscopy, nuclear magnetic resonance (¹H NMR) spectroscopy and gel permeation chromatography (GPC). PUC-PUN co-assembled nanomicelles were prepared by electrostatic interaction between PUC and PUN micelles, which showed acid-sensitive property. When the pH of the solution was decreased from 7.4 to 6.5, PUC-PUN-1 micelles showed negative-to-positive charge-reversal property among these micelles. The results of stability and cell experiments demonstrated that PUC-PUN-1 micelles not only had excellent stability in simulated normal physiological environment but also could obviously enhance the cellular uptake efficiency. PUC-PUN-1 micelles had low cytotoxicity against SGC-7901 and MGC-803 cells, whereas PUC-PUN-1/DOX micelles had higher cytotoxicity compared to pure DOX and PUN-1/DOX micelles. Moreover, the results of in vivo antitumor activity experiments showed that PUC-PUN-1/DOX micelles had better tumor inhibition ability and safety than pure DOX. In addition, the results of in vitro drug release experiments indicated that PUC-PUN-1/DOX micelles had almost no burst release or leakage of drugs in pH 7.4 environment. However, the drug release was accelerated in pH 5.0, which followed Fickian diffusion mechanism.

Nano-sulforaphane attenuates PhIP-induced early abnormal embryonic neuro-development

BACKGROUND

2-Amino-1-methyl-6-phenylimidazo[4,5-b]pyrimidine (PhIP), one of the most abundant heterocyclic aromatic amines (HAA) formed by cooking meat at high temperatures, may modify humans and rodents through the metabolic process prior to affecting nervous system development. In humans and rodents may be modified by metabolic processes and then affecting nervous system development.

METHODS

In this paper, PhIP was used to prepare a chicken embryo model with abnormal embryonic nervous system defects. Sulforaphane (SFN) is a derivative of a glucosinolate, which is abundant in cruciferous vegetables, and can pass through the placental barrier. Moreover, SFN has antioxidant and anti-apoptotic functions and is considered as a bioactive antioxidant with significant neuroprotective effects. Nano-sulforaphane (Nano-SFN, sulforaphane nanoparticles) was prepared by self-assembly using biocompatible, biodegradable methoxy polyethylene glycol 5000-b-polyglutamic acid 10,000 (mPEG5K-PGA10K) as the substrate, to explore the new application of Nano-SFN and its modified compounds as leading compounds in protecting against the abnormal development of the embryonic nervous system.

RESULTS

The results show that Nano-SFN could protect against PhIP-induced central nervous system (CNS, derived from neural tube) and peripheral nervous system (PNS, derived from neural crest cells, NCCs) defects and neural tube defects (NTDs), and increase the embryo survival rate.

CONCLUSIONS

This study indicates that Nano-SFN can effectively alleviate the developmental defects of embryonic nervous system induced by PhIP in the microenvironment and has a protective effect on embryonic development. It not only helps with expanding the application of SFN and improving its medicinal value, but also provides a possibility of SFN being developed as a novel drug for neuroprotection.

Tuning the PEG surface density of the PEG-PGA enveloped Octaarginine-peptide Nanocomplexes

One of the main limitations of protein drugs is their restricted capacity to cross biological barriers. We have previously reported nanostructured complexes of insulin and modified octaarginine (C12-r8), enveloped by a polyethyleneglycol-polyglutamic acid (PEG-PGA) protective shell, and showed their capacity to overcome different barriers associated to the oral modality of administration. The objective of this work was to produce the said nanocomplexes with structurally diverse PEG-PGA shells, i.e. with different chain lengths and PEG substitution degrees, and comparatively analyze their PEG surface density and subsequent impact on their interaction with mucus glycoproteins and Caco-2 cells. The new PEG-PGA enveloped C12-r8-insulin nanocomplexes (ENCPs) exhibited a narrow size distribution (average size of 210-239 nm), a neutral surface charge and a 100% insulin association efficiency (final insulin loading of 16.5-29.6% w/w). Proton nuclear magnetic resonance (¹H NMR) analysis indicated the possibility to modulate the PEG density on the ENCPs from 6.7 to 44.5 PEG chains per 100 nm². This increase in the ENCPs PEG surface density resulted in their reduced interaction with mucins in vitro, while their interaction with Caco-2 cells in vitro remained unaltered. Overall, these data indicate the capacity to tune the surface characteristics of the ENCPS in order to maximize the capacity of these nanocarriers to overcome barriers associated to mucosal surfaces.

PH and redox dual-responsive polymeric micelles with charge conversion for paclitaxel delivery

Here we demonstrate a type of pH and redox dual-responsive micelles, which were self-assembled in aqueous solution by an amphiphilic polymer, methoxypoly(ethylene glycol)-cystamine-poly(L-glutamic acid)-imidazole (mPEG-SS-PGA-IM). Considering tumor cells or tissues exhibiting low pH values and high glutathione (GSH) concentration, mPEG-SS-PGA-IM micelles possessed the charge conversion at pH of tumor tissues, which can facilitate cellular uptake of tumor cells. Furthermore, mPEG-SS-PGA-IM micelles can escape from endo/lysosomes based on the proton sponge effect, following degraded by higher concentration of GSH in cytoplasm. CLSM images of HCT116 cells indicated that mPEG-SS-PGA-IM micelles can escape from endo/lysosomes and enter cytoplasm. MTT assay showed that (paclitaxel) PTX-loaded mPEG-SS-PGA-IM micelles had higher cytotoxicity against HCT116 cells compared with PTX-loaded mPEG-PBLG and mPEG-SS-PBLG micelles. These results indicated that these mPEG-SS-PGA-IM micelles, as novel and effective pH- and redox-responsive nanocarriers, have great potential to both improve drug targeting efficiency while also enhancing the antitumor efficacy of PTX.

Construction of a sensitive electrochemical sensor based on 1T-MoS2 nanosheets decorated with shape-controlled gold nanostructures for the voltammetric determination of doxorubicin

An innovative and portable design to fabricate an electrochemical sensor based on metallic phase MoS₂ (1T-MoS₂) decorated with shape-dependent gold nanostructures for the determination of doxorubicin (DOX) is presented. In this context, homogenous and uniform single-crystal gold nanospheres (AuNSPs) and nanorods (AuNRDs) were firstly synthesized by seeded growth approach. Afterwards, AuNSPs and AuNRDs were anchored on 1T-MoS₂ surfaces to construct the desired electrochemical sensing platform towards the DOX assay. 1T-MoS₂ was exfoliated by metal intercalation process using NaK metal alloys. The structure and surface morphology of 1T-MoS₂, AuNSPs, and AuNRDs were characterized by XPS, Raman, UV-vis, TEM, and SEM. The electrochemical behavior of DOX using various MoS₂-based electrochemical sensors prepared on screen-printed electrode (SPE) was examined by cyclic voltammetry and adsorptive stripping differential pulse voltammetry. The electrocatalytic efficiency of AuNRDs on 1T-MoS₂ was also compared with that of AuNSPs on 1T-MoS₂, and it showed much better electrocatalytic activity towards the DOX. A nanocomposite prepared with AuNRDs and 1T-MoS₂ on SPE (AuNRDs/1T-MoS₂/SPE) exhibited a linear relationship between peak current and DOX concentration in the range 0.01-9.5 μM with a detection limit of 2.5 nM. The AuNRDs/1T-MoS₂/SPE was successfully applied to the sensitive and rapid determination of DOX in spiked human serum samples with satisfactory recoveries in the range 99.2-100.8%. Graphical abstract Schematic representation of a portable design for electrochemical sensor based on shape-controlled gold nanostructures decorated on metallic phase molybdenum disulfide (1T-MoS₂) towards the sensitive determination of doxorubicin.

Polymeric nanocarriers as stimuli-responsive systems for targeted tumor (cancer) therapy: Recent advances in drug delivery

In the last decade, considerable attention has been devoted to the use of biodegradable polymeric materials as potential drug delivery carriers. However, bioavailability and drug release at the disease site remain uncontrollable even with the use of polymeric nanocarriers. To address this issue, successful methodologies have been developed to synthesize polymeric nanocarriers incorporated with regions exhibiting a response to stimuli such as redox potential, temperature, pH, and light. The resultant stimuli-responsive polymeric nanocarriers have shown tremendous promise in drug delivery applications, owing to their ability to enhance the bioavailability of drugs at the disease site. In such systems, drug release is controlled in response to specific stimuli, either exogenous or endogenous. This review reports recent advances in the design of stimuli-responsive nanocarriers for drug delivery in cancer therapy. In particular, the synthetic methodologies investigated to date to introduce different types of stimuli-responsive elements within the biomaterials are described. The sufficient understanding of these stimuli-responsive nanocarriers will allow the development of a better drug delivery system that will allow us to solve the challenges encountered in targeted cancer therapy.

Doxorubicin - chitosan - hydroxyapatite composite coatings on titanium alloy for localized cancer therapy

The doxorubicin-chitosan composite is deposited electrochemically on the Ti alloy post hydroxyapatite coated for reducing the side effects by sustaining release of drugs localized near the tumor to achieve the inhibition or apoptosis of cancer. The possibility of danger in case of exfoliation of medicine composite and HA agglomerates from the alloy surface due to the dynamic erosion of blood flow could be overcome with the additional surface modification by the electrochemical deposition way. The cathodic polarization tests coupled with electrochemical reactions were analyzed to speculate the deposition mechanism of doxorubicin, spectrophotometer (UV visible spectrometer) to measure doxorubicin loading and release, field emission scanning electron microscope (FESEM) to observe surface morphology, Fourier transform infrared (FTIR) spectroscopy for chemical bonding of composites, and X-ray diffractometry (XRD) for crystal structure. The cell culture was carried out to analyze the drug efficacy on cell viability. It is concluded that doxorubicin-chitosan composites can be successfully deposited on the uncoated and hydroxyapatite-coated titanium specimen alloy by electrochemical methods. Both have revealed the sustaining drug release for a month and the latter with high porosity can enhance the drug loading to 37.46 μg/cm², revealing this electrochemical method is a practical way to load doxorubicin cancer drug releasing locally to significantly reduce the amount of medication needed for future clinical applications.

In Vitro Release Test of Nano-drug Delivery Systems Based on Analytical and Technological Perspectives

Background:

Nanotech products are gaining more attention depending on their advantages for improving drug solubility, maintenance of drug targeting, and attenuation of drug toxicity. In vitro release test is the critical physical parameter to determine the pharmaceutical quality of the product, to monitor formulation design and batch-to-batch variation.

Methods:

Spectrophotometric and chromatographic methods are mostly used in quantification studies from in vitro release test of nano-drug delivery systems. These techniques have advantages and disadvantages with respect to each other considering dynamic range, selectivity, automation, compatibility with in vitro release media and cost per sample.

Results:

It is very important to determine the correct kinetic profile of active pharmaceutical substances. At this point, the analytical method used for in vitro release tests has become a very critical parameter to correctly assess the profiles. In this review, we provided an overview of analytical methods applied to the in vitro release assay of various nanopharmaceuticals.

Conclusion:

This review presents practical direction on analytical method selection for in vitro release test on nanopharmaceuticals. Moreover, precautions on analytical method selection, optimization and validation were discussed.

Release of Pharmaceutical Peptides in an Aggregated State: Using Fibrillar Polymorphism to Modulate Release Levels

Traditional approaches to achieve sustained delivery of pharmaceutical peptides traditionally use co-excipients (e.g., microspheres and hydrogels). Here, we investigate the release of an amyloidogenic glucagon analogue (3474) from an aggregated state and the influence of surfactants on this process. The formulation of peptide 3474 in dodecyl maltoside (DDM), rhamnolipid (RL), and sophorolipid (SL) led to faster fibrillation. When the aggregates were subjected to multiple cycles of release by repeated resuspension in fresh buffer, the kinetics of the release of soluble peptide 3474 from different surfactant aggregates all followed a simple exponential decay fit, with half-lives of 5–18 min and relatively constant levels of release in each cycle. However, different amounts of peptide are released from different aggregates, ranging from 0.015 mg/mL (3475-buffer) up to 0.03 mg/mL (3474-DDM), with 3474-buffer and 3474-RL in between. In addition to higher release levels, 3474-DDM aggregates showed a different amyloid FTIR structure, compared to 3474-RL and 3474-SL aggregates and a faster rate of degradation by proteinase K. This demonstrates that the stability of organized peptide aggregates can be modulated to achieve differences in release of soluble peptides, thus coupling aggregate polymorphism to differential release profiles. We achieved aggregate polymorphism by the addition of different surfactants, but polymorphism may also be reached through other approaches, including different excipients as well as changes in pH and salinity, providing a versatile handle to control release profiles.

pH-Responsive Zwitterionic Copolymer DHA-PBLG-PCB for Targeted Drug Delivery: A Computer Simulation Study

In this work, the self-assembled behaviors of zwitterionic copolymer docosahexaenoic acid- b-poly(γ-benzyl-l-glutamate)- b-poly(carboxybetaine methacrylate) (DHA-PBLG-PCB) and the loading and release mechanism of the anticancer drug doxorubicin (DOX) was investigated via computer simulations. The effects of polymer concentration, drug content, and pH on polymeric micelles were explored by dissipative particle dynamics (DPD) simulations. Simulation results show that DHA-PBLG₁₅-PCB₁₀ can self-assemble into core-shell micelles; in addition, the drug-loaded micelles have a pH-responsive feature. DOX can be encapsulated into the core-shell micelle under normal physiological pH conditions, whereas it can be released under acidic pH conditions. The self-assembled behaviors of copolymer DHA-PBLG-PEG were also studied to have a comparison with those of DHA-PBLG-PCB. The DHA-PBLG₁₅-PCB₁₀ system has a stable structure and it has a great potential to serve as drug delivery vehicles for targeted drug delivery.

Structure-activity relationship of serotonin derived tocopherol lipids

Tocopherol-based lipids are widely used for nucleic acid delivery. Using tocopherol molecules, we designed and synthesized 5-HT functionalized lipids by tethering 5-hydroxytryptamine (5-HT), a small molecule ligand as the head group to a natural amphiphilic molecule namely α-tocopherol (Vitamin E). This is with the aim of delivering nucleic acids specifically into cells expressing the serotonin receptors (5-hydroxytryptamine[5-HT]) which are abundant in the central nervous system. In order to achieve target recognition, we adopted an approach wherein two structurally different lipid molecules having serotonin as the head group was conjugated to tocopherol via different linkers thus generating lipids with either free -NH₂ or -OH moiety. The corresponding lipids designated as Lipid A (Tocopheryl carbonate serotonin-NH₂) and Lipid B (Tocopheryl 2-hydroxy propyl ammonium serotonin-OH), were formulated with co-lipids 1,2-dioleoyl-sn-glycero-3-phosphatidyl-ethanolamine (DOPE) and 1,2-dioleoyl-sn-glycero-sn-3-phosphatidylcholine (DOPC) and evaluated for their ability to deliver plasmid DNA through reporter gene expression assays in vitro. Furthermore, the physicochemical characteristics and cellular interactions of the formulations were examined using serotonin-receptor enriched cells in order to distinguish the structural and functional attributes of both lipids. Cell-based gene expression studies reveal that in comparison to Lipid A, a formulation of Lipid B prepared with DOPE as the co-lipid, contributes to efficient uptake leading to significant enhancement in transfection. Specific interactions explored by molecular docking studies suggests the role of the hydroxyl moiety and the enantiospecific significance of serotonin- conjugated tocopherol lipids in recognizing these receptors thus signifying a promising lipid-based approach to target the serotonin receptors in the central nervous system.

Polypeptides Micelles Composed of Methoxy-Poly(Ethylene Glycol)-Poly(l-Glutamic Acid)-Poly(l-Phenylalanine) Triblock Polymer for Sustained Drug Delivery

Methoxy-poly(ethylene glycol)-poly(l-glutamic acid)-poly(l-phenylalanine) triblock polymers with different architecture were synthesized as drug carrier to obtain sustained and controlled release by tuning the composition. These triblock polymers were prepared by ring opening polymerization and poly(ethylene glycol) was used as an initiator. Polymerization was confirmed by ¹H NMR, FT-IR and gel penetration chromatography. The polymers can self-assemble to form micelles in aqueous medium and their critical micelle concentrations values were examined. The micelles were spherical shape with size of 50–100 nm and especially can arranged in a regular manner. Sorafenib was selected as the model drug and the drug loading performance was dependent on the composition of the block copolymer. In vitro drug release indicated that the polymers can realize controlled and sustained drug release. Furthermore, in vitro cytotoxicity assay showed that the polymers were biocompatible and the drug-loaded micelles can increase toxicity towards tumor cells. Confocal fluorescence microscopy assays illustrated that the micelles can be uptaken quickly and release drug persistently to inhibit tumor cell growth.

Hyaluronic acid-based nano-sized drug carrier-containing Gellan gum microspheres as potential multifunctional embolic agent

The purpose of this study was to develop a gellan gum-based multifunctional embolic agent. Calibrated spherical gellan gum and nanoparticle-containing gellan gum microspheres were prepared via water-in oil emulsification method. Self-assembled nanoparticles composed of short-chain hyaluronic acid and polyethylenimine as the doxorubicin carrier were prepared. The short-chain hyaluronic acid/polyethylenimine/ doxorubicin (sHH/PH/Dox) with the mean size was 140 ± 8 nm. To examine sHH/PH/Dox nanoparticle uptake into cells, the results confirmed that sHH/PH nanoparticles as drug carrier can facilitate the transport of doxorubicin into HepG2 liver cancer cells. Subsequently, sHH/PH/Dox merged into the gellan gum (GG) microspheres forming GG/sHH/PH/Dox microsphere. After a drug release experiment lasting 45 days, the amount of released doxorubicin from 285, 388, and 481 μm GG/sHH/PH/Dox microspheres were approximately 4.8, 1.8 and 1.1-fold above the IC50 value of the HepG2 cell. GG/sHH/PH/Dox microspheres were performed in rabbit ear embolization model and ischemic necrosis on ear was visible due to the vascular after 8 days. Regarding the application of this device in the future, we aim to provide better embolization agents for transcatheter arterial chemoembolization (TACE).

Research progresses on the functional polypeptides in the detection and imaging of breast cancer

Polypeptides as functional groups continue to garner significant interest in the detection and imaging of breast cancer, working as recognition elements, signal sources, building blocks and therapeutic reagents, etc.

Synthesis and characterization of novel carboxymethyl Assam Bora rice starch for the controlled release of cationic anticancer drug based on electrostatic interactions

Carboxymethyl Assam Bora rice starch (CM-ABRS) was chemically synthesized in non-aqueous medium with the optimum degree of substitution (DS) of 1.23, and physicochemically characterized by FT-IR, DSC, XRD, and SEM analysis. Comparative evaluation of CM-ABRS with native starch (ABRS) for powder flow characteristics, swelling index, apparent solubility, rheological properties, textural properties, and mucoadhesive studies were carried out. The aim of the current work was to investigate the potential of CM-ABRS as a novel carrier for the water-soluble chemotherapeutic, doxorubicin hydrochloride (DOX). Formation of drug/polymer complex (DOX-CM-ABRS) via electrostatic interaction has been evaluated for the controlled release of DOX in three different pH media (phosphate-buffered saline (PBS), pH 7.4, 6.8, and 5.5). In vitro drug release studies illustrated faster release of drug in PBS at pH 5.5 as compared to pH 6.8 and pH 7.4, respectively, indicating the importance of pH-sensitive drug release from the DOX-CM-ABRS complex in malignant tissues.

Generation of a co-culture cell micropattern model to simulate lung cancer bone metastasis for anti-cancer drug evaluation

A549/OB co-culture micropattern was fabricated through μ-eraser strategy to mimic lung cancer bone metastasis for DOX efficacy evaluation.

Dual-responsive core-crosslinked polyphosphoester-based nanoparticles for pH/redox-triggered anticancer drug delivery

The paper focuses on the preparation of biodegradable pH/redox dual-responsive core-crosslinked nanoparticles loaded with dual anticancer drugs PTX and DOX via synergetic electrostatic as well as hydrophobic interactions and their further application in tumor chemotherapy.

Facile preparation of pH/reduction dual-responsive prodrug nanohydrogels for tumor-specific intracellular triggered release with enhanced anticancer efficiency

Facile approach was developed for biocompatible and biodegradable pH/reduction dual-responsive nano-prodrug for tumor specific intracellular triggered release.

ANGPTL2 expression in gastric cancer tissues and cells and its biological behavior

AIM

To explore expression of angiopoietin-like protein 2 (ANGPTL2) and its effect on biological behavior such as proliferation and invasiveness in gastric cancer.

METHODS

Western blotting was used to detect expression of ANGPTL2 in 60 human normal gastric tissues, 60 human gastric cancer tissues and gastric cell lines including GES-1, N87, SGC7901, BGC823 and PAMC82. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and Transwell assay were used to detect the proliferation and invasive ability of gastric cancer cells.

RESULTS

Compared to normal tissues, ANGPTL2 protein levels were significantly upregulated in gastric tissues, and this level was closely correlated with gastric tumor grade, clinical stage and lymph node metastasis. Compared to GES-1 cells, ANGPTL2 mRNA and protein levels were significantly increased in gastric cancer cells including N87, SGC7901, BGC823 and PAMC82. The expression of ANGPTL2 in highly malignant gastric cancer cell lines BGC823 and PAMC82 was significantly higher than in low malignancy gastric cancer cell lines N87 and SGC7901. MTT and Transwell experiments indicated that the proliferation rate and invasive ability of stable overexpressed gastric cancer cells was faster than in cells transfected with Lv-NC and blank control cells, and the invasive ability of stable overexpressed gastric cancer cells was higher than that of cells transfected with Lv-NC and blank control cells.

CONCLUSION

ANGPTL2 contributed to proliferation and invasion of gastric cancer cells. In clinical treatment, ANGPTL2 may become a new target for treatment of gastric cancer.

Doxorubicin carriers based on Au nanoparticles – effect of shape and gold-drug linker on the carrier toxicity and therapeutic performance

Gold nanoparticles (AuNPs) prepared by the Turkevich method and near-IR absorbing non-spherical anisotropic nanotriangles (AuNTs) prepared by the thiosulfate method were used for doxorubicin binding.

Construction of novel pH-sensitive hybrid micelles for enhanced extracellular stability and rapid intracellular drug release

Novel pH-sensitive hybrid micelles with high entrapment efficiency were constructed to realize rapid intracellular drug release without premature release.