Validation of a Janus role of methotrexate-based PEGylated chitosan nanoparticles in vitro

A pHe sensitive nanodrug for collaborative penetration and inhibition of metastatic tumors

Current chemotherapies for metastatic tumors are seriously restricted by limited drug infiltration and deficient disturbance of metastasis-associated complex pathways involving tumor cell autocrine as well as paracrine loops in the microenvironment (TME). Of note, cancer-associated fibroblasts (CAFs) play a predominant role in shaping TME favoring drug resistance and metastasis. Herein, we constructed a tumor extracellular pH (pH_e) sensitive methotrexate-chitosan conjugate (MTX-GC-DEAP) and co-assembled it with quercetin (QUE) to achieve co-delivered nanodrugs (MTX-GC-DEAP/QUE). The pH_e sensitive protonation and disassembly enabled MTX-GC-DEAP/QUE for stroma-specific delivery of QUE and positive-charged MTX-GC-DEAP molecular conjugates, thereby achieving deep tumor penetration via the combination of QUE-mediated CAF inactivation and adsorption-mediated transcytosis. On the basis of significantly promoted drug availability, a strengthened "omnidirectional" inhibition of pre-metastatic initiation was generated both in vitro and in vivo from the CAF inactivation-mediated reversion of metastasis-promoting environments as well as the inhibition of epithelial-mesenchymal transition, local and blood vessel invasion via QUE-mediated direct regulation on tumor cells. Our tailor-designed versatile nanodrug provides a deep insight into potentiating multi-faceted penetration of multi-mechanism-based regulating agents for intensive metastasis inhibition.

Epigallocatechin gallate: Phytochemistry, bioavailability, utilization challenges, and strategies

Epigallocatechin gallate (EGCG), a green tea catechin, has gained the attention of current study due to its excellent health-promoting effects. It possesses anti-obesity, antimicrobial, anticancer, anti-inflammatory activities, and is under extensive investigation in functional foods for improvement. It is susceptible to lower stability, lesser bioavailability, and lower absorption rate due to various environmental, processing, formulations, and gastrointestinal conditions of the human body. Therefore, it is the foremost concern for the researchers to enhance its bioactivity and make it the most suitable therapeutic compound for its clinical applications. In the current review, factors affecting the bioavailability of EGCG and the possible strategies to overcome these issues are reviewed and discussed. This review summarizes structural modifications and delivery through nanoparticle-based approaches including nano-emulsions, encapsulations, and silica-based nanoparticles for effective use of EGCG in functional foods. Moreover, recent advances to enhance EGCG therapeutic efficacy by specifically targeting its molecules to increase its bioavailability and stability are also described. PRACTICAL APPLICATIONS: The main green tea constituent EGCG possesses several health-promoting effects making EGCG a potential therapeutic compound to cure ailments. However, its low stability and bioavailability render its uses in many disorders. Synthesizing EGCG prodrugs by structural modifications helps against its low bioavailability and stability by overcoming premature degradation and lower absorption rate. This review paper summarizes various strategies that benefit EGCG under different physiological conditions. The esterification, nanoparticle approaches, silica-based EGCG-NPs, and EGCG formulations serve as ideal EGCG modification strategies to deliver superior concentrations with lesser toxicity for its efficient penetration and absorption across cells both in vitro and in vivo. As a result of EGCG modifications, its bioactivities would be highly improved at lower doses. The protected or modified EGCG molecule would have enhanced potential effects and stability that would contribute to the clinical applications and expand its use in various food and cosmetic industries.

Photolytic Controlled Release Formulation of Methotrexate Loaded in Chitosan/TiO2 Nanoparticles for Breast Cancer

A new system composed of chitosan nanoparticles loaded with methotrexate (MTX-CS-NPs) and functionalized with photocatalytic TiO₂ nanoparticles (TiO₂-NPs) was prepared. This system is expected to initiate polymeric rupture of MTX-CS-NPs and subsequently release MTX, upon illumination with UV light. MTX-CS-NPs were prepared and characterized in terms of particle size, charge, polydispersity and drug release before and after coating with TiO₂-NPs. The release of MTX in vitro was studied in dark, light and UV light. Finally, coated and uncoated MTX-CS-NPs were studied in vitro using MCF-7 cell line. The functionalized NPs were larger in size, more polydisperse and carried higher positive charges compared to the unfunctionalized NPs. The entrapment efficacy was high reaching 75% and was not affected by coating with MTX-CS-NPs. Further, less than 5% of methotrexate was released after 80 h from uncoated NPs and the release was not enhanced by UV illumination of the particles. In contrast, the release from functionalized NPs was enhanced, reaching 40% after 80 h, as the particles were stroked with UV light and as the amount of TiO₂-NPs used in coating increased. Finally, coating the MTX-CS-NPs with TiO₂-NPs significantly enhanced their cytotoxicity on MCF-7 cells. The coated MTX-CS-NPs recorded low cell viabilities compared to the other formulations. In conclusion, the drug release of MTX-CS-NPs could be triggered and controlled remotely by coating with TiO₂-NPs, which maybe more effective in cancer treatment.

Fabrication of eco-friendly chitosan functionalized few-layered WS2 nanocomposite implanted with ruthenium nanoparticles for in vitro antibacterial and anticancer activity: Synthesis, characterization, and pharmaceutical applications

The abundance of two-dimensional (2D) components has provided them with a broad material platform for building nano and atomic-level applications. So, 2D nanomaterials are unique because of their physicochemical properties. Over many years, graphene is a conventional 2D layered element that has significant attention in the scientific community. In recent years numerous new 2D nanomaterials other than graphene have been reported. The study of 2D nanomaterials is also in its infant stages, with the majority of research focusing on the explanation of special material properties, but very few articles are focusing on the biological applications of 2D nanomaterials. As a result, we focused on the transition metal dichalcogenides (TMDCs) such as MoS₂ and WS₂, which were emerging and exciting groups of elements with display great opportunities in several fields, such as cancer nanomedicine. Herein, we synthesized biologically active CS/WS₂/Ru composite by liquid exfoliation approach. The CS/WS₂/Ru composites exhibit significant antibacterial action towards (S. aureus, and E. coli) bacteria. Also, the composite suggests synergetic anticancer action against MCF-7 cancer cells. These reports are possible to explore the innovative aspects of biological outcomes in carcinological applications.

Anticancer effect of X-Ray triggered methotrexate conjugated albumin coated bismuth sulfide nanoparticles on SW480 colon cancer cell line

The application of nanoparticles (NPs) as radio-sensitizers and carriers has opened up a new horizon to overcome the limitations of chemo and radiotherapy. In this study, bovine serum albumin-coated Bi₂S₃ NPs (Bi₂S₃@BSA NPs) were synthesized and evaluated in terms of their ability to be used as a radio-sensitizer and carrier for methotrexate (MTX). Physicochemical properties of MTX conjugated Bi₂S₃@BSA NPs (Bi₂S₃@BSA-MTX NPs) were characterized by DLS, TEM, FTIR, UV/Vis, and XRD analyses. After the evaluation of cellular uptake and intracellular localization, the cytotoxicity of the combination of Bi₂S₃@BSA-MTX NPs and X-Ray radiation was analyzed against the SW480 cell line. The synthesized NPs exhibited spherical-like shapes and homogenous morphology, possessing a hydrodynamic diameter of 140.2 ± 5.71 nm (mean ± SD) and zeta potential of -25 mV. Also, the release study showed that the release of MTX is faster and higher in the presence of the proteinase K enzyme than the absence of the enzyme. The results of in-vitro chemo-radiation therapy indicated that the viability of treated cells with Bi₂S₃@BSA-MTX NPs is significantly lower than the cells treated with Bi₂S₃@BSA NPs. Furthermore, cells treated with Bi₂S₃@BSA-MTX NPs showed a lower degree of viability when combined with X-Ray radiation in comparison with the absence of irradiation, which confirmed the ability of the Bi₂S₃@BSA-MTX NPs as radio-sensitizer.

Hypoxia-Triggered Transforming Immunomodulator for Cancer Immunotherapy via Photodynamically Enhanced Antigen Presentation of Dendritic Cell

A key factor for successful cancer immunotherapy (CIT) is the extent of antigen presentation by dendritic cells (DCs) that phagocytize tumor-associated antigens (TAA) in the tumor site and migrate to tumor draining lymph nodes (TDLN) for the activation of T cells. Although various types of adjuvant delivery have been studied to enhance the activity of the DCs, poor delivery efficiency and depleted population of tumor infiltrating DCs have limited the efficacy of CIT. Herein, we report a hypoxia-responsive mesoporous silica nanocarrier (denoted as CAGE) for an enhanced CIT assisted by photodynamic therapy (PDT). In this study, CAGE was designed as a hypoxia-responsive transforming carrier to improve the intracellular uptake of nanocarriers and the delivery of adjuvants to DCs. Furthermore, PDT was exploited for the generation of immunogenic debris and recruitment of DCs in a tumor site, followed by enhanced antigen presentation. Finally, a significant inhibition of tumor growth was observed in vivo, signifying that the PDT would be a promising solution for DC-based immunotherapy.

A novel intracellular pH-responsive formulation for FTY720 based on PEGylated graphene oxide nano-sheets

OBJECTIVE

This study was performed to investigate a novel pH-responsive nanocarrier based on modified nano graphene oxide (nGO) to promote the acid-triggered intracellular release of a poorly soluble drug, FTY720.

METHODS

To synthesize a drug conjugated to modified nGO, first the polyethylene glycol (PEG) was conjugated to nGO, then the produced PEG-nGO was functionalized with the anticancer drug, FTY720, through amide bonding. It was characterized by the scanning electron microscopy (SEM), the atomic force microscopy (AFM), the Fourier transform infrared (FTIR) spectroscopy and the UV-vis spectroscopy. In vitro drug release of the FTY720-conjugated PEG-nGO was evaluated at pH 7.4 and 4.6 PBS at 37 °C. Furthermore, the antineoplastic action of unloaded and drug-loaded carrier against the human breast adenocarcinoma cell line MCF7 was explored using MTT and BrdU assays.

RESULTS

Characterization methods indicated successful drug deposition on the surface of nGO. In vitro, drug release results revealed a significantly faster release of FTY720 from PEG-nGO at acidic pH, compared with physiological pH. The proliferation assays proved that the unloaded nGO had no significant cytotoxicity against MCF7 cells, while free FTY720- and FTY720-loaded PEG-nGO had an approximately equal cytotoxic effect on the MCF7 cells. It was found that the extended release characteristic of FTY720 was well fitted to Korsmeyer-Peppas model and the release profile of FTY720 from PEG-nGO is diffusion controlled.

CONCLUSION

PEGylated GO can act as a pH-responsive drug carrier to improve the efficacy of anticancer drug delivery.

Synthesis and characterisation of PEG modified chitosan nanocapsules loaded with thymoquinone

Thymoquinone (TQ), a major bioactive compound of Nigella sativa seeds has several therapeutic properties. The main drawback in bringing TQ to therapeutic application is that it has poor stability and bioavailability. Hence a suitable carrier is essential for TQ delivery. Recent studies indicate biodegradable polymers are potentially good carriers of bioactive compounds. In this study, polyethylene glycol (PEG) modified chitosan (Cs) nanocapsules were developed as a carrier for TQ. Aqueous soluble low molecular weight Cs and PEG was selected among different biodegradable polymers based on their biocompatibility and efficacy as a carrier. Optimisation of synthesis of nanocapsules was done based on particle size, PDI, encapsulation efficiency and process yield. A positive zeta potential value of +48 mV, indicating good stability was observed. Scanning electron microscope and atomic-force microscopy analysis revealed spherical shaped and smooth surfaced nanocapsules with size between 100 to 300 nm. The molecular dispersion of the TQ in Cs PEG nanocapsules was studied using X-ray powder diffraction. The Fourier transform infrared spectrum of optimised nanocapsule exhibited functional groups of both polymer and drug, confirming the presence of Cs, PEG and TQ. In vitro drug release studies showed that PEG modified Cs nanocapsules loaded with TQ had a slow and sustained release.

Synthesis of protein-coated biocompatible methotrexate-loaded PLA-PEG-PLA nanoparticles for breast cancer treatment

Background

PLA-PEG-PLA triblock polymer nanoparticles are promising tools for targeted dug delivery. The main aim in designing polymeric nanoparticles for drug delivery is achieving a controlled and targeted release of a specific drug at the therapeutically optimal rate and choosing a suitable preparation method to encapsulate the drug efficiently, which depends mainly on the nature of the drug (hydrophilic or hydrophobic). In this study, methotrexate (MTX)-loaded nanoparticles were prepared by the double emulsion method.

Method

Biodegradable polymer polyethylene glycol-polylactide acid tri-block was used with poly(vinyl alcohol) as emulsifier. The resulting methotrexate polymer nanoparticles were coated with bovine serum albumin in order to improve their biocompatibility. This study focused on particle size distribution, zeta potential, encapsulation efficiency, loading capacity, and in vitro drug release at various concentrations of PVA (0.5%, 1%, 2%, and 3%).

Results

Reduced particle size of methotrexate-loaded nanoparticles was obtained using lower PVA concentrations. Enhanced encapsulation efficiency and loading capacity was obtained using 1% PVA. FT-IR characterization was conducted for the void polymer nanoparticles and for drug-loaded nanoparticles with methotrexate, and the protein-coated nanoparticles in solid state showed the structure of the plain PEG-PLA and the drug-loaded nanoparticles with methotrexate. The methotrexate-loaded PLA-PEG-PLA nanoparticles have been studied in vitro; the drug release, drug loading, and yield are reported.

Conclusion

The drug release profile was monitored over a period of 168 hours, and was free of burst effect before the protein coating. The results obtained from this work are promising; this work can be taken further to develop MTX based therapies.

Inclusion of a pH-responsive amino acid-based amphiphile in methotrexate-loaded chitosan nanoparticles as a delivery strategy in cancer therapy

The encapsulation of antitumor drugs in nanosized systems with pH-sensitive behavior is a promising approach that may enhance the success of chemotherapy in many cancers. The nanocarrier dependence on pH might trigger an efficient delivery of the encapsulated drug both in the acidic extracellular environment of tumors and, especially, in the intracellular compartments through disruption of endosomal membrane. In this context, here we reported the preparation of chitosan-based nanoparticles encapsulating methotrexate as a model drug (MTX-CS-NPs), which comprises the incorporation of an amino acid-based amphiphile with pH-responsive properties (77KS) on the ionotropic complexation process. The presence of 77KS clearly gives a pH-sensitive behavior to NPs, which allowed accelerated release of MTX with decreasing pH as well as pH-dependent membrane-lytic activity. This latter performance demonstrates the potential of these NPs to facilitate cytosolic delivery of endocytosed materials. Outstandingly, the cytotoxicity of MTX-loaded CS-NPs was higher than free drug to MCF-7 tumor cells and, to a lesser extent, to HeLa cells. Based on the overall results, MTX-CS-NPs modified with the pH-sensitive surfactant 77KS could be potentially useful as a carrier system for intracellular drug delivery and, thus, a promising targeting anticancer chemotherapeutic agent.

Engineering Biomaterial-Drug Conjugates for Local and Sustained Chemotherapeutic Delivery

The standard of care for cancer patients includes surgical resection, radiation, and chemotherapy with cytotoxic chemotherapy drugs usually part of the treatment. However, these drugs are commonly associated with cardiotoxicity, ototoxicity, nephrotoxicity, peripheral neuropathy, and myelosuppression. Strategies to deliver cytotoxic chemotherapy drugs while reducing secondary toxicity and increasing tumor dosing would therefore be desirable. This goal can be achieved through the use of controlled release drug carrier systems. The aim of this review is to provide an overview of clinically used drug carrier systems and recently developed approaches for drug-biomaterial conjugation.

Drug/Dye-Loaded, Multifunctional PEG-Chitosan-Iron Oxide Nanocomposites for Methotraxate Synergistically Self-Targeted Cancer Therapy and Dual Model Imaging

Multifunctional nanocomposites hold great potential to integrate therapeutic and diagnostic functions into a single nanoscale structure. In this paper, we prepared the MTX-PEG-CS-IONPs-Cy5.5 nanocomposites by functionalizing the surface of chitosan-decorated iron oxide nanoparticles (CS-IONPs) with polyethylene glycolated methotraxate (MTX-PEG) and near-infrared fluorescent cyanin dye (Cy5.5). A clinically useful PEGylated anticancer prodrug, MTX-PEG, was also developed as a tumor cell-specific targeting ligand for self-targeted cancer treatment. In such nanocomposites, the advantage was that the orthogonally functionalized, self-targeted MTX-PEG-CS-IONPs-Cy5.5 can synergistically combine an early phase selective tumor-targeting efficacy with a late-phase cancer-killing effect, which was also confirmed by dual model (magnetic resonance and fluorescence) imaging. Furthermore, with the aids of the folate (FA) receptor-mediated endocytosis (able to turn cellular uptake "off" in normal cells and "on" in cancer cells) and pH/intracellular protease-mediated hydrolyzing peptide bonds (able to turn drug release "off" in systemic circulation and "on" inside endo/lysosomes), the MTX-PEG-CS-IONPs-Cy5.5 could deliver MTX to FA receptors-overexpressed cancer cells, showing the improved anticancer activity with the reduced side effects. Together, the MTX-PEG-CS-IONPs-Cy5.5 could act as a highly convergent, flexible, and simplified system for dual model imaging and synergistically self-targeted cancer therapy, holding great promise for versatile biomedical applications in future.

Self-targeted, bacillus-shaped, and controlled-release methotrexate prodrug polymeric nanoparticles for intratumoral administration with improved therapeutic efficacy in tumor-bearing mice

Self-targeted, bacillus-shaped, and controlled-release methotrexate prodrug polymeric nanoparticles for highly efficient cancer chemotherapy: more elongated is better.

Validation of a dual role of methotrexate-based chitosan nanoparticles in vivo

Surface functionalization of a PEGylated chitosan nanoparticle with dual-acting methotrexate drives a tumor-targeting effect and also introduces an anticancer effect.