Precise Targeting of Liver Tumor Using Glycol Chitosan Nanoparticles: Mechanisms, Key Factors, and Their Implications

ROS-responsive glycol chitosan-linked prodrug nanoparticle as a nanoplatform for tumor chemo-photodynamic therapy

Herein, we designed and synthesized novel reactive oxygen species (ROS)-responsive glycol chitosan-doxorubicin (DOX) prodrug via a ROS-cleavable thioketal (TK) linker. The obtained GC-TK-DOX formed self-assembled nanoparticles of 312 nm in aqueous media. Photosensitizers zinc phthalocyanine (ZnPc)-loaded GC-TK-DOX (GC-TK-DOX/ZnPc) nanoparticles were fabricated by using a dialysis approach. The GC-TK-DOX and GC-TK-DOX/ZnPc nanoparticles were nearly spherical by transmission electron microscopy (TEM) observation. Under 660-nm laser irradiation, GC-TK-DOX/ZnPc could generate singlet oxygen. Further, GC-TK-DOX/ZnPc nanoparticles exhibited ROS-sensitive release of DOX and ZnPc in vitro. GC-TK-DOX/ZnPc with laser irradiation showed more drug uptake and higher cytotoxic effects than GC-TK-DOX/ZnPc without irradiation, free DOX and GC-TK-DOX in HeLa tumor cells. Overall, these findings suggested that GC-TK-DOX/ZnPc could be a promising nanoarchitecture for synergetic chemo-photodynamic therapy against tumors.

Chitosan-based nanosystems for cancer diagnosis and therapy: Stimuli-responsive, immune response, and clinical studies

Cancer, a global health challenge of utmost severity, necessitates innovative approaches beyond conventional treatments (e.g., surgery, chemotherapy, and radiation therapy). Unfortunately, these approaches frequently fail to achieve comprehensive cancer control, characterized by inefficacy, non-specific drug distribution, and the emergence of adverse side effects. Nanoscale systems based on natural polymers like chitosan have garnered significant attention as promising platforms for cancer diagnosis and therapy owing to chitosan's inherent biocompatibility, biodegradability, nontoxicity, and ease of functionalization. Herein, recent advancements pertaining to the applications of chitosan nanoparticles in cancer imaging and drug/gene delivery are deliberated. The readers are introduced to conventional non-stimuli-responsive and stimuli-responsive chitosan-based nanoplatforms. External triggers like light, heat, and ultrasound and internal stimuli such as pH and redox gradients are highlighted. The utilization of chitosan nanomaterials as contrast agents or scaffolds for multimodal imaging techniques e.g., magnetic resonance, fluorescence, and nuclear imaging is represented. Key applications in targeted chemotherapy, combination therapy, photothermal therapy, and nucleic acid delivery using chitosan nanoformulations are explored for cancer treatment. The immunomodulatory effects of chitosan and its role in impacting the tumor microenvironment are analyzed. Finally, challenges, prospects, and future outlooks regarding the use of chitosan-based nanosystems are discussed.

Effective and prolonged targeting of a nanocarrier to the inflammation site by functionalization with ZnBPMP and chitosan

Efficient and selective targeting of inflamed tissues/organs is critical for diagnosis and therapy. Although nanomaterials themselves have an intrinsic advantage due to their size for targeting inflammation sites, additional functionalization of the nanomaterials with proper targeting moieties is desired to enhance the targeting efficiency. In this study, we aimed to improve the inflammation targeting characteristics of a pluronic-based nanocarrier, which has advantages as a nanosized delivery cargo for diverse molecules, by conjugating with chitosan and ZnBPMP (two Zn(II) ions chelated 2,6-bis[(bis(2-pyridylmethyl)amino)-methyl]-4-methylphenol) moiety. Specific and significant cellular uptake and interaction between the nanocarrier functionalized with ZnBPMP ligand and chitosan to an apoptosis-induced immune cell line were observed in vitro. An inflammation model in the mouse ear caused by skin hypersensitivity was used to evaluate the effect of functionalization with chitosan and ZnBPMP moiety by comparing with various control groups. Functionalization of the nanocarrier with chitosan greatly enhanced the in vivo circulation time of the nanocarrier, so prolonged targeting ability of the nanocarrier to the inflamed ear was achieved. Additional ZnBPMP functionalization to chitosan-functionalized nanocarrier also resulted in significantly improved initial targeting and further enhancement in the targeting until 5 days to the inflamed ear and the decreased non-specific accumulation of the nanocarrier to the remaining body. Thus, developed nanocarrier has a high potential as a drug delivery carrier as well as a diagnostic agent to the inflammation sites.

Electronic waste generation, recycling and resource recovery: Technological perspectives and trends

The growing population and increased disposal of end-of-life (EoL) electrical and electronic products have caused serious concerns to the environment and human health. Electronic waste (e-waste) is a growing problem because the quantity and the rate at which it is generated has increased exponentially in the last 5 years. The rapid changes or upgradation in technologies, IT requirements for working or learning from home during COVID-19, manufacturers releasing new electronic gadgets and devices that serves the consumers comfort and a declension in services has contributed to an increase in the e-waste or waste of electrical and electronic equipment (WEEE) generation rates. The current status of e-waste generation, handling procedures and regulatory directives in USA, EU, China, India, Vietnam and Gulf Cooperation Council (GCC) countries are presented in this review. The recent developments in e-waste recycling methods/recovery of base and precious metals, the advantages and limitations of hydrometallurgy, pyrometallurgy, biohydrometallurgy and pyrolysis are discussed. Considering the impediments in the present technologies, the extraction of valuable resources, i.e. precious metals, from e-waste using suitable biocatalysts shows promising applications. This review also stresses on the research needs to assess the economic effects of involving different unit operations/process industries for resource recovery, reuse and recycling.

Chitosan Nanomedicine in Cancer Therapy: Targeted Delivery and Cellular Uptake

Nanomedicine has gained much attention for the management and treatment of cancers due to the distinctive physicochemical properties of the drug-loaded particles. Chitosan's cationic nature is attractive for the development of such particles for drug delivery, transfection, and controlled release. The particle properties can be improved by modification of the polymer or the particle themselves. The physicochemical properties of chitosan particles are analyzed in 126 recent studies, which allows to highlight their impact on passive and active targeted drug delivery, cellular uptake, and tumor growth inhibition (TGI). From 2012 to 2019, out of 40 in vivo studies, only 4 studies are found reporting a reduction in tumor size by using chitosan particles while all other studies reported tumor growth inhibition relative to controls. A total of 23 studies are analyzed for cellular uptake including 12 studies reporting cellular uptake mechanisms. Understanding and exploiting the processes involved in targeted delivery, endocytosis, and exocytosis by controlling the physicochemical properties of chitosan particles are important for the development of safe and efficient nanomedicine. It is concluded based on the recent literature available on chitosan particles that combination therapies can play a pivotal role in transformation of chitosan nanomedicine from bench to bedside.

The Evaluation of Drug Delivery Nanocarrier Development and Pharmacological Briefing for Metabolic-Associated Fatty Liver Disease (MAFLD): An Update

Current research indicates that the next silent epidemic will be linked to chronic liver diseases, specifically non-alcoholic fatty liver disease (NAFLD), which was renamed as metabolic-associated fatty liver disease (MAFLD) in 2020. Globally, MAFLD mortality is on the rise. The etiology of MAFLD is multifactorial and still incompletely understood, but includes the accumulation of intrahepatic lipids, alterations in energy metabolism, insulin resistance, and inflammatory processes. The available MAFLD treatment, therefore, relies on improving the patient's lifestyle and multidisciplinary pharmacotherapeutic options, whereas the option of surgery is useless without managing the comorbidities of the MAFLD. Nanotechnology is an emerging approach addressing MAFLD, where nanoformulations are suggested to improve the safety and physicochemical properties of conventional drugs/herbal medicines, physical, chemical, and physiological stability, and liver-targeting properties. A wide variety of liver nanosystems were constructed and delivered to the liver, only those that addressed the MAFLD were discussed in this review in terms of the nanocarrier classes, particle size, shape, zeta potential and offered dissolution rate(s), the suitable preparation method(s), excipients (with synergistic effects), and the suitable drug/compound for loading. The advantages and challenges of each nanocarrier and the focus on potential promising perspectives in the production of MAFLD nanomedicine were also highlighted.

Smart Responsive Quercetin-Conjugated Glycol Chitosan Prodrug Micelles for Treatment of Inflammatory Bowel Diseases

The incidence and progression of inflammatory bowel disease are closely related to oxidative stress caused by excessive production of reactive oxygen species (ROS). To develop an efficacious and safe nanotherapy against inflammatory bowel diseases (IBD), we designed a novel pH/ROS dual-responsive prodrug micelle GC-B-Que as an inflammatory-targeted drug, which was comprised by active quercetin (Que) covalently linked to biocompatible glycol chitosan (GC) by aryl boronic ester as a responsive linker. The optimized micelles exhibited well-controlled physiochemical properties and stability in a physiological environment. Time-dependent NMR spectra traced the changes in the polymer structure in the presence of H₂O₂, confirming the release of the drug. The in vitro drug release studies indicated a low release rate (<20 wt %) in physiological conditions, but nearly complete release (>95 wt % after 72 h incubation) in a pH 5.8 medium containing 10 μM H₂O₂, exhibiting a pH/ROS dual-responsive property and sustained release behavior. Importantly, the negligible drug release in a simulated gastric environment in 1 h allowed us to perform intragastric administration, which has potential to achieve the oral delivery by mature enteric-coating modification in future. Further in vivo activities and biodistribution experiments found that the GC-B-Que micelles tended to accumulate in intestinal inflammation sites and showed better therapeutic efficacy than the free drugs (quercetin and mesalazine) in a colitis mice model. Typical inflammatory cytokines including TNF-α, IL-6, and iNOS were significantly suppressed by GC-B-Que micelle treatment. Our work promoted inflammatory-targeted delivery and intestinal drug accumulation for active single drug quercetin and improved the therapeutic effect of IBD. The current study also provided an alternative strategy for designing a smart responsive nanocarrier for a catechol-based drug to better achieve the target drug delivery.

Tumor-Targeting Glycol Chitosan Nanoparticles for Cancer Heterogeneity

Nanomedicine is extensively employed for cancer treatment owing to its unique advantages over conventional drugs and imaging agents. This increased attention to nanomedicine, however, has not fully translated into clinical utilization and patient benefits due to issues associated with reticuloendothelial system clearance, tumor heterogeneity, and complexity of the tumor microenvironment. To address these challenges, efforts are being made to modify the design of nanomedicines, including optimization of their physiochemical properties, active targeting, and response to stimuli, but these studies are often performed independently. Combining favorable nanomedicine designs from individual studies may improve therapeutic outcomes, but, this is difficult to achieve as the effects of different designs are interconnected and often conflicting. Glycol chitosan nanoparticles (CNPs) are shown to accumulate in tumors, suggesting that this type of nanoparticle may constitute a good basis for the additional modification of nanoparticles. Here, multifunctional glycol CNPs designed to overcome multiple obstacles to their use are described and key factors influencing in vivo targeted delivery, targeting strategies, and interesting stimulus-responsive designs for improving cancer nanomedicine are discussed.

Deep Tumor Penetration of Doxorubicin-Loaded Glycol Chitosan Nanoparticles Using High-Intensity Focused Ultrasound

The dense extracellular matrix (ECM) in heterogeneous tumor tissues can prevent the deep tumor penetration of drug-loaded nanoparticles, resulting in a limited therapeutic efficacy in cancer treatment. Herein, we suggest that the deep tumor penetration of doxorubicin (DOX)-loaded glycol chitosan nanoparticles (CNPs) can be improved using high-intensity focused ultrasound (HIFU) technology. Firstly, we prepared amphiphilic glycol chitosan-5β-cholanic acid conjugates that can self-assemble to form stable nanoparticles with an average of 283.7 ± 5.3 nm. Next, the anticancer drug DOX was simply loaded into the CNPs via a dialysis method. DOX-loaded CNPs (DOX-CNPs) had stable nanoparticle structures with an average size of 265.9 ± 35.5 nm in aqueous condition. In cultured cells, HIFU-treated DOX-CNPs showed rapid drug release and enhanced cellular uptake in A549 cells, resulting in increased cytotoxicity, compared to untreated DOX-CNPs. In ECM-rich A549 tumor-bearing mice, the tumor-targeting efficacy of intravenously injected DOX-CNPs with HIFU treatment was 1.84 times higher than that of untreated DOX-CNPs. Furthermore, the deep tumor penetration of HIFU-treated DOX-CNPs was clearly observed at targeted tumor tissues, due to the destruction of the ECM structure via HIFU treatment. Finally, HIFU-treated DOX-CNPs greatly increased the therapeutic efficacy at ECM-rich A549 tumor-bearing mice, compared to free DOX and untreated DOX-CNPs. This deep penetration of drug-loaded nanoparticles via HIFU treatment is a promising strategy to treat heterogeneous tumors with dense ECM structures.

Preparation, evaluation, and in vitro cytotoxicity studies of artesunate-loaded glycyrrhetinic acid decorated PEG-PLGA nanoparticles

OBJECTIVE

The objective of this study was to prepare the liver targeting drug delivery system (TDDS) of artesunate (ART)-loaded polyethylene glycol (PEG)-poly(d,l-lactic-co-glycolic) acid (PLGA) nanoparticles (NPs) modified by glycyrrhetinic acid (GA), and evaluate its in vitro cytotoxicity.

SIGNIFICANCE

The GA-PEG-PLGA-ART NPs enhanced the in vitro cytotoxicity on HCC cell lines. The development of GA-PEG-PLGA NPs will greatly push the clinical applications of ART as a novel anticancer drug.

METHODS

The NPs were prepared using solvent evaporation method, and the formulation was optimized through an orthogonal design. In addition, physical properties were determined, including particle size, polydispersity index (PDI), zeta potential (ZP), morphology, drug loading capacity (LC) and encapsulation efficiency (EE), and in vitro drug release. Moreover, the in vitro cytotoxicity of NPs with three human cancer cell lines viz. HepG2, Hep3B, and SMCC-7721 was conducted using the SRB assay. Additionally, lyophilization was conducted to improve the long-term physical stability.

RESULTS

The GA-PEG-PLGA-ART NPs have spherical shape, small particle size (around 88 nm) with a narrow size distribution (PDI < 0.3), high drug LC (up to 59.3 ± 1.65%), and high EE (up to 73.13 ± 5.17%). In vitro drug release behavior showed that drugs were released from NPs in a sustained and controlled release pattern. Cytotoxicity study indicated the NPs achieved lower cancer cell survival fraction. The GA-PEG-PLGA NPs freeze-dried with 3% (w/v) of mannitol showed better effect on long-term physical stability.

CONCLUSION

The GA-PEG-PLGA-ART NPs appear as a potential liver targeted intracellular delivery platform for ART.

Smart stimuli-responsive drug delivery systems based on cyclodextrin: A review

Stimulated by researches in materials chemistry and medicine fields, drug delivery has entered a new stage of development. Drug delivery systems have been extensively studied according to the differences in the drug therapeutic environment such as pH, light, temperature, magnet, redox, enzymes, etc. Cyclodextrin is a smart tool that has been proven to be used in the preparation of drug delivery, and has become a new area of concern in recent years. In this review, we discuss recent research advances in smart stimuli-responsive cyclodextrin-based drug delivery. First, different stimuli-responsive drug delivery systems based on cyclodextrin are introduced and classified. Then, the characteristics of different types of stimuli-responsive drug delivery systems are described, and their applications are emphasized. Finally, current challenges and future development opportunities of smart stimuli-responsive drug delivery systems based on cyclodextrin are discussed.

Chitosan Nanoparticles for Therapy and Theranostics of Hepatocellular Carcinoma (HCC) and Liver-Targeting

Chitosan nanoparticles are well-known delivery systems widely used as polymeric carriers in the field of nanomedicine. Chitosan is a carbohydrate of natural origin: it is a biodegradable, biocompatible, mucoadhesive, polycationic polymer and it is endowed with penetration enhancer properties. Furthermore, it can be easily derivatized. Hepatocellular carcinoma (HCC) represents a remarkable health problem because current therapies, that include surgery, liver transplantation, trans-arterial embolization, chemoembolization and chemotherapy, present significant limitations due to the high risk of recurrence, to a lack of drug selectivity and to other serious side effects. Therefore, there is the need for new therapeutic strategies and for improving the liver-targeting to HCC. Nanomedicine consists in the use of nanoscale carriers as delivery systems to target and deliver drugs and/or diagnostic agents to specific organs or tissues. Chitosan and its derivatives can be successfully used in the preparation of nanoparticles that, for their peculiar surface-properties, can specifically interact with liver tumor, by passive and active targeting. This review concerns the use of chitosan nanoparticles for the therapy and theranostics of HCC and liver-targeting.

Flash Fabrication of Orally Targeted Nanocomplexes for Improved Transport of Salmon Calcitonin across the Intestine

Salmon calcitonin (sCT) is a potent calcium-regulating peptide hormone and widely applied for the treatment of some bone diseases clinically. However, the therapeutic usefulness of sCT is hindered by the frequent injection required, owing to its short plasma half-life and therapeutic need for a high dose. Oral delivery is a popular modality of administration for patients because of its convenience to self-administration and high patient compliance, while orally administered sCT remains a great challenge currently due to the existence of multiple barriers in the gastrointestinal (GI) tract. Here, we introduced an orally targeted delivery system to increase the transport of sCT across the intestine through both the paracellular permeation route and the bile acid pathway. In this system, sCT-based glycol chitosan-taurocholic acid conjugate (GC-T)/dextran sulfate (DS) ternary nanocomplexes (NC-T) were produced by a flash nanocomplexation (FNC) process in a kinetically controlled mode. The optimized NC-T exhibited well-controlled properties with a uniform and sub-60 nm hydrodynamic diameter, high batch-to-batch reproducibility, good physical or chemical stability, as well as sustained drug release behaviors. The studies revealed that NC-T could effectively improve the intestinal uptake and permeability, owing to its surface functionalization with the taurocholic acid ligand. In the rat model, orally administered NC-T showed an obvious hypocalcemia effect and a relative oral bioavailability of 10.9%. An in vivo assay also demonstrated that NC-T induced no observable side effect after long-term oral administration. As a result, the orally targeted nanocomplex might be a promising candidate for improving the oral transport of therapeutic peptides.

Combination of KRAS gene silencing and PI3K inhibition for ovarian cancer treatment

The phosphoinositide 3-kinase (PI3K) and RAS signaling pathways are frequently co-activated and altered during oncogenesis. Owing to their regulatory cross-talk, the early attempts of targeting only one pathway have mostly ended up promoting the development of drug resistance. Here, we propose using small interfering RNA (siRNA) therapeutics to directly target the undruggable KRAS (siKRAS) in combination with the pan-PI3K inhibitor GDC-0941 (GDC) to simultaneously block both PI3K and RAS signaling, thereby exerting synergistic anti-tumor effects on ovarian cancers with PTEN deficiency and KRAS^G12D mutation. For successful delivery of siKRAS, tGC/psi-nanoparticle formulation of polymerized siRNA and thiol-modified glycol chitosan nanoparticle-was used for KRAS specific inhibition in vitro and in vivo. GDC or siKRAS monotherapy each impede downstream signaling, leading to some delay in cell proliferation and migration. When combined, however, they engender much higher inhibition of PI3K signaling and stimulation of apoptosis in an ovarian allograft model compared to monotherapies. Our results show the feasibility of developing new combination strategies for the management of multiple oncogenic mutations activating PI3K and RAS signaling.

Glycol Chitosan: A Water-Soluble Polymer for Cell Imaging and Drug Delivery

Glycol chitosan (GC), a water-soluble chitosan derivative with hydrophilic ethylene glycol branches, has both hydrophobic segments for the encapsulation of various drugs and reactive functional groups for facile chemical modifications. Over the past two decades, a variety of molecules have been physically encapsulated within or chemically conjugated with GC and its derivatives to construct a wide range of functional biomaterials. This review summarizes the recent advances of GC-based materials in cell surface labeling, multimodal tumor imaging, and encapsulation and delivery of drugs (including chemotherapeutics, photosensitizers, nucleic acids, and antimicrobial agents) for combating cancers and microbial infections. Besides, different strategies for GC modifications are also highlighted with the aim to shed light on how to endow GC and its derivatives with desirable properties for therapeutic purposes. In addition, we discuss both the promises and challenges of the GC-derived biomaterials.

Dual-Modal Imaging-Guided Precise Tracking of Bioorthogonally Labeled Mesenchymal Stem Cells in Mouse Brain Stroke

Noninvasive and precise stem cell tracking after transplantation in living subject is very important to monitor both stem cell destinations and their in vivo fate, which is closely related to their therapeutic efficacy. Herein, we developed bicyclo[6.1.0]nonyne (BCN)-conjugated glycol chitosan nanoparticles (BCN-NPs) as a delivery system of dual-modal stem cell imaging probes. Near-infrared fluorescent (NIRF) dye Cy5.5 was chemically conjugated to the BCN-NPs, and then oleic acid-coated superparamagnetic iron oxide nanoparticles (OA-Fe₃O₄ NPs) were encapsulated into BCN-NPs, resulting in Cy5.5-labeled and OA-Fe₃O₄ NP-encapsulated BCN-NPs (BCN-dual-NPs). For bioorthogonal labeling of human adipose-derived mesenchymal stem cells (hMSCs), first, hMSCs were treated with tetra-acetylated N-azidoacetyl-d-mannosamine (Ac₄ManNAz) for generating azide (-N₃) groups onto their surface via metabolic glycoengineering. Second, azide groups on the cell surface were successfully chemically labeled with BCN-dual-NPs via bioorthogonal click chemistry in vitro. This bioorthogonal labeling of hMSCs could greatly increase the cell labeling efficiency, safety, and imaging sensitivity, compared to only nanoparticle-derived labeling technology. The dual-modal imaging-guided precise tracking of bioorthogonally labeled hMSCs was tested in the photothrombotic stroke mouse model via intraparenchymal injection. Finally, BCN-dual-NPs-labeled hMSCs could be effectively tracked by their migration from the implanted site to the brain stroke lesion using NIRF/T₂-weighted magnetic resonance (MR) dual-modal imaging for 14 days. Our observation would provide a potential application of bioorthogonally labeled stem cell imaging in regenerative medicine by providing safety and high labeling efficiency in vitro and in vivo.

Advances in chitosan-based nanoparticles for oncotherapy

Chitosan has attracted considerable attention as an anti-tumor drug carrier material in recent years, which is due to its biocompatibility and biodegradability, as well as the simple and mild preparing techniques of drug-loaded nanoparticles. Chitosan-based nanoparticles can deliver various anti-tumor agents to specific tumor tissues by passive and active targeting mechanisms, including traditional chemotherapeutic agents, DNA or siRNA, proteins, photosensitizers and so on. In this review, we summarized the factors affecting the anti-tumor efficacy of chitosan-based nanoparticles, to aid exploring the function-structure relationship. The recent studies on chitosan-based nanoparticles for oncotherapy were highlighted, including their structures, properties and pharmacological effects. Finally, we offered our perspectives on the challenges and future development of this area.

Chitosan nanopolymers: An overview of drug delivery against cancer

Cancer is becoming a major reason for death troll worldwide due to the difficulty in finding an efficient, cost effective and target specific method of treatment or diagnosis. The variety of cancer therapy used in the present scenario have painful side effects, low effectiveness and high cost, which are some major drawbacks of the available therapies. Apart from the conventional cancer therapy, nanotechnology has grown extremely towards treating cancer. Nanotechnology is a promising area of science focusing on developing target specific drug delivery system for carrying small or large active molecules to diagnose and treat cancer cells. In the field of nanoscience, Chitosan nanopolymers (ChNPs) are been emerging as a potential carrier due to their biodegradability and biocompatibility. The easy modification and versatility in administration route of ChNPs has attracted attention of researchers towards loading chemicals, proteins and gene drugs for target specific therapy of cancer cells. Therefore, the present review deals with the growing concern towards cancer therapy, introduction of ChNPs, mode of action and other strategies employed by researchers till date towards cancer treatment and diagnosis ChNPs.

Functional Peptide Nanofibers with Unique Tumor Targeting and Enzyme-Induced Local Retention Properties

An effective tumoral delivery system should show minimal removal by the reticuloendothelial system (RES), promote tumor uptake and penetration, and minimize on-site clearance. This study reports the design and synthesis of advanced self-assembling peptide nanofiber precursor (NFP) analogues. The peptidic nature of NFP offers the design flexibility for on-demand customization with imaging agents and surface charges while maintaining a set size, allowing for real-time monitoring of kinetic and dynamic tumoral delivery by multimodal fluorescence/positron emission tomography/computed tomography (fluo/PET/CT) imaging, for formulation optimization. The optimized glutathione (GSH)-NFP displays a reduced capture by the RES as well as excellent tumor targeting and tissue invasion properties compared to naive NFP. Inside a tumor, GSH-NFP can structurally transform into ten times larger interfibril networks, serving as in situ depot that promotes weeks-long local retention. This nanofiber, which can further be designed to release the active pharmacophores within a tumor microenvironment, displays a superior therapeutic efficacy for inhibiting disease progression and improving the survival of animals bearing triple-negative breast cancer tumors compared to free drug and liposome formulation of the drug, in addition to a favorable toxicity profile.

The cutting-edge technologies of siRNA delivery and their application in clinical trials

siRNA therapeutics allows precise regulation of disease specific gene expression to treat various diseases. Although gene silencing approaches using siRNA therapeutics shows some promising results in the treatment of gene-related diseases, the practical applications has been limited by problems such as inefficient in vivo delivery to target cells and nonspecific immune responses after systemic or local administration. To overcome these issues, various in vivo delivery platforms have been introduced. Here we provide an overview for three different platform technologies for the in vivo delivery of therapeutic siRNAs (siRNA-GalNAc conjugate, SAMiRNA technology, and LNP-based delivery method) and their applications in the treatment of various diseases. In addition, a brief introduction to some rare diseases and mechanisms of siRNA therapeutics-mediated treatment is described.

Physiologically stable F127-GO supramolecular hydrogel with sustained drug release characteristic for chemotherapy and photothermal therapy

The F127-GO-DOX supramolecular hydrogel system with sustained drug release characteristic for chemotherapy and photothermal therapy.

Multicomponent, Tumor-Homing Chitosan Nanoparticles for Cancer Imaging and Therapy

Current clinical methods for cancer diagnosis and therapy have limitations, although survival periods are increasing as medical technologies develop. In most cancer cases, patient survival is closely related to cancer stage. Late-stage cancer after metastasis is very challenging to cure because current surgical removal of cancer is not precise enough and significantly affects bystander normal tissues. Moreover, the subsequent chemotherapy and radiation therapy affect not only malignant tumors, but also healthy tissues. Nanotechnologies for cancer treatment have the clear objective of solving these issues. Nanoparticles have been developed to more accurately differentiate early-stage malignant tumors and to treat only the tumors while dramatically minimizing side effects. In this review, we focus on recent chitosan-based nanoparticles developed with the goal of accurate cancer imaging and effective treatment. Regarding imaging applications, we review optical and magnetic resonance cancer imaging in particular. Regarding cancer treatments, we review various therapeutic methods that use chitosan-based nanoparticles, including chemo-, gene, photothermal, photodynamic and magnetic therapies.

Deep tissue penetration of nanoparticles using pulsed-high intensity focused ultrasound

Recently, ultrasound (US)-based drug delivery strategies have received attention to improve enhanced permeation and retention (EPR) effect-based passive targeting efficiency of nanoparticles in vitro and in vivo conditions. Among the US treatment techniques, pulsed-high intensity focused ultrasound (pHIFU) have specialized for improving tissue penetration of various macromolecules and nanoparticles without irreversible tissue damages. In this study, we have demonstrated that pHIFU could be utilized to improve tissue penetration of fluorescent dye-labeled glycol chitosan nanoparticles (FCNPs) in femoral tissue of mice. pHIFU could improve blood flow of the targeted-blood vessel in femoral tissue. In addition, tissue penetration of FCNPs was specifically increased 5.7-, 8- and 9.3-folds than that of non-treated (0 W pHIFU) femoral tissue, when the femoral tissue was treated with 10, 20 and 50 W of pHIFU, respectively. However, tissue penetration of FCNPs was significantly reduced after 3 h post-pHIFU treatment (50 W). Because overdose (50 W) of pHIFU led to irreversible tissue damages, including the edema and chapped red blood cells. These overall results support that pHIFU treatment can enhance the extravasation and tissue penetration of FCNPs as well as induce irreversible tissue damages. We expect that our results can provide advantages to optimize pHIFU-mediated delivery strategy of nanoparticles for further clinical applications.