Folate-Decorated Hybrid Polymeric Nanoparticles for Chemically and Physically Combined Paclitaxel Loading and Targeted Delivery

Enhanced anticancer activity of (-)-epigallocatechin-3-gallate (EGCG) encapsulated NPs toward colon cancer cell lines

(-)-Epigallocatechin-3-gallate (EGCG), a bioactive polyphenol of green tea, has chemo-preventive effects against various cancer cells. Nanoparticles (NPs) carrying different ligands are able to specifically interact with their receptors on different cancer cells that can provide effective release of cytotoxic drugs. In the present study, we have prepared EGCG entrapped NPs using PLGA (poly(d,l-lactide-co-glycolide)). Polyethylene glycol (PEG) and folic acid (FA) via double emulsion solvent evaporation (DESE) method obtained PLGA-EGCG (P-E), PLGA-PEG-EGCG (PP-E), and PLGA-PEG-FA-EGCG (PPF-E). Nanoformulations had been characterized with 1H NMR and FT-IR techniques, AFM, and DLS. PPF-E NPs showed an average size of 220 nm. Analysis of zeta potential confirmed the stability of NPs. HCT-116, HT-29, HCT-15, and HEK 293 cells were treated with both the prepared NPs and free EGCG (0-140 μM). Result showed PPF-E NPs had improved delivery, uptake and cell cytotoxicity toward human folic acid receptor-positive (FR+) colorectal cancer (CRC) cells as mainly on HCT-116 compared to HT-29, but not on the folic acid-negative cells (FR-) as HCT-15. PPF-E NPs enhanced intracellular reactive oxygen species (ROS) level in absence of N-acetyl-l-cysteine (NAC), elevated DNA fragmentation level, and increased apoptotic cell death at higher doses compared to other two NPs and free EGCG. In conclusion, PPF-E NPs exerted greater efficacy than PP-E, P-E, and free EGCG in HCT-116 cells.

Tumor-On-A-Chip Models for Predicting In Vivo Nanoparticle Behavior

Nanosized drug formulations are broadly explored for the improvement of cancer therapy. Prediction of in vivo nanoparticle (NP) behavior, however, is challenging, given the complexity of the tumor and its microenvironment. Microfluidic tumor-on-a-chip models are gaining popularity for the in vitro testing of nanoparticle targeting under conditions that simulate the 3D tumor (microenvironment). In this review, following a description of the tumor microenvironment (TME), the state of the art regarding tumor-on-a-chip models for investigating nanoparticle delivery to solid tumors is summarized. The models are classified based on the degree of compartmentalization (single/multi-compartment) and cell composition (tumor only/tumor microenvironment). The physiological relevance of the models is critically evaluated. Overall, microfluidic tumor-on-a-chip models greatly improve the simulation of the TME in comparison to 2D tissue cultures and static 3D spheroid models and contribute to the understanding of nanoparticle behavior. Interestingly, two interrelated aspects have received little attention so far which are the presence and potential impact of a protein corona as well as nanoparticle uptake through phagocytosing cells. A better understanding of their relevance for the predictive capacity of tumor-on-a-chip systems and development of best practices will be a next step for the further refinement of advanced in vitro tumor models.

Structure-switchable aptamer-arranged reconfigurable DNA nanonetworks for targeted cancer therapy

The structural DNA nanotechnology holds great potential application in bioimaging, drug delivery and cancer therapy. Herein, an intelligent aptamer-incorporated DNA nanonetwork (Apt-Nnes) is demonstrated for cancer cell imaging and targeted drug delivery, which essentially is a micron-scale pattern with the thickness of double-stranded monolayer. Cancer cell-surface receptors can make it perform magical transformation into small size of nanosheet intermediates and specifically enter target cells. The binding affinity of Apt-Nnes is increased by 3-fold due to multivalent binding effect of aptamers and it can maintain the structural integrity in fetal bovine serum (FBS) for 8 h. More interestingly, target cancer cells can cause the structural disassembly, and each resulting unit transports 4963 doxorubicin (Dox) into target cells, causing the specific cellular cytotoxicity. The cell surface receptor-mediated disassembly of large size of DNA nanostructures into small size of fractions provides a valuable insight into developing intelligent DNA nanostructure suitable for biomedical applications.

Herbal nanomedicines: Recent advancements, challenges, opportunities and regulatory overview

BACKGROUND

Herbal Nano Medicines (HNMs) are nano-sized medicine containing herbal drugs as extracts, enriched fractions or biomarker constituents. HNMs have certain advantages because of their increased bioavailability and reduced toxicities. There are very few literature reports that address the common challenges of herbal nanoformulations, such as selecting the type/class of nanoformulation for an extract or a phytochemical, selection and optimisation of preparation method and physicochemical parameters. Although researchers have shown more interest in this field in the last decade, there is still an urgent need for systematic analysis of HNMs.

PURPOSE

This review aims to provide the recent advancement in various herbal nanomedicines like polymeric herbal nanoparticles, solid lipid nanoparticles, phytosomes, nano-micelles, self-nano emulsifying drug delivery system, nanofibers, liposomes, dendrimers, ethosomes, nanoemulsion, nanosuspension, and carbon nanotube; their evaluation parameters, challenges, and opportunities. Additionally, regulatory aspects and future perspectives of herbal nanomedicines are also being covered to some extent.

METHODS

The scientific data provided in this review article are retrieved by a thorough analysis of numerous research and review articles, textbooks, and patents searched using the electronic search tools like Sci-Finder, ScienceDirect, PubMed, Elsevier, Google Scholar, ACS, Medline Plus and Web of Science.

RESULTS

In this review, the authors suggested the suitability of nanoformulation for a particular type of extracts or enriched fraction of phytoconstituents based on their solubility and permeability profile (similar to the BCS class of drugs). This review focuses on different strategies for optimising preparation methods for various HNMs to ensure reproducibility in context with all the physicochemical parameters like particle size, surface area, zeta potential, polydispersity index, entrapment efficiency, drug loading, and drug release, along with the consistent therapeutic index.

CONCLUSION

A combination of herbal medicine with nanotechnology can be an essential tool for the advancement of herbal medicine research with enhanced bioavailability and fewer toxicities. Despite the challenges related to traditional medicine's safe and effective use, there is huge scope for nanotechnology-based herbal medicines. Overall, it is well stabilized that herbal nanomedicines are safer, have higher bioavailability, and have enhanced therapeutic value than conventional herbal and synthetic drugs.

Dual targeting nanoparticles for epilepsy therapy

Dual-targeting nanoparticles containing D-T7 peptide and Tet1 peptide were designed for carrying lamotrigine (LTG) to cross the blood–brain barrier and further concentrate at the epilepsy lesions for treating epilepsy with high biosafety.

In silico studies of interactions of peptide-conjugated cholesterol metabolites and betulinic acid with EGFR, LDR, and N-terminal fragment of CCKA receptors

In this work, we designed three new ligands by conjugating cholesterol metabolites 3-hydroxy-5-cholestenoic acid (3-HC) and 3-oxo-4-cholestenoic acid (3-OC) and the natural tri-terpenoid betulinic acid with the tumor-targeting peptide YHWYGYTPQNVI. Molecular interactions with the unconjugated peptide and the conjugates were examined with three receptors that are commonly overexpressed in pancreatic adenocarcinoma cells using ligand docking and molecular dynamics. This study demonstrated the utility of the designed conjugates as a valuable scaffold for potentially targeting EGFR and LDLR receptors. Our results indicate that the conjugates showed strong binding affinities and formation of stable complexes with EGFR, while the unconjugated peptide, BT-peptide conjugate, an 3-HC-peptide conjugate showed the formation of fairly stable complexes with LDLR receptor. For EGFR, two receptor kinase domains were explored. Interactions with the N-terminal domain of CCKA-R were relatively weaker. For LDLR, binding occurred in the beta-propeller region. For the N-terminal fragment of CCKA-R, the conjugates induced significant conformational changes in the receptor. The molecular dynamic simulations for 100 ns demonstrate that BT-peptide conjugates and the unconjugated peptide had the highest binding and formed the most stable complexes with EGFR. RMSD and trajectory analyses indicate that these molecules transit to a dynamically stable configuration in most cases within 60 ns. NMA analysis indicated that amongst the conjugates that showed relatively higher interactions with the respective receptors, the highest potential for deformability was seen for the N-terminal-47 amino acid region of the CCKA-R receptor with and the lowest for the LDLR-receptor. Thus, the newly designed compounds may be evaluated in the future toward developing drug delivery materials for targeting tumor cells overexpressing LDLR or EGFR.

Paclitaxel: Application in Modern Oncology and Nanomedicine-Based Cancer Therapy

Paclitaxel is a broad-spectrum anticancer compound, which was derived mainly from a medicinal plant, in particular, from the bark of the yew tree Taxus brevifolia Nutt. It is a representative of a class of diterpene taxanes, which are nowadays used as the most common chemotherapeutic agent against many forms of cancer. It possesses scientifically proven anticancer activity against, e.g., ovarian, lung, and breast cancers. The application of this compound is difficult because of limited solubility, recrystalization upon dilution, and cosolvent-induced toxicity. In these cases, nanotechnology and nanoparticles provide certain advantages such as increased drug half-life, lowered toxicity, and specific and selective delivery over free drugs. Nanodrugs possess the capability to buildup in the tissue which might be linked to enhanced permeability and retention as well as enhanced antitumour influence possessing minimal toxicity in normal tissues. This article presents information about paclitaxel, its chemical structure, formulations, mechanism of action, and toxicity. Attention is drawn on nanotechnology, the usefulness of nanoparticles containing paclitaxel, its opportunities, and also future perspective. This review article is aimed at summarizing the current state of continuous pharmaceutical development and employment of nanotechnology in the enhancement of the pharmacokinetic and pharmacodynamic features of paclitaxel as a chemotherapeutic agent.

Nanoformulations of Coumarins and the Hybrid Molecules of Coumarins with Potential Anticancer Effects

Coumarins are the secondary metabolites of some plants, fungi, and bacteria. Coumarins and the hybrid molecules of coumarins are the compounds which have been widely studied for their potential anticancer effects. They belong to benzopyrone chemical class, more precisely benzo-α-pyrones, where benzene ring is fused to pyrone ring. In nature, coumarins are found in higher plants like Rutaceae and Umbelliferae and some essential oils like cinnamon bark oil, cassia leaf oil and lavender oil are also rich in coumarins. The six main classes of coumarins are furanocoumarins, dihydrofuranocoumarins, pyrano coumarins, pyrone substituted coumarins, phenylcoumarins and bicoumarins. As well as their wide range of biological activities, coumarins and the hybrid molecules of coumarins are proven to have an important role in anticancer drug development due to the fact that many of its derivatives have shown an anticancer activity on various cell lines. Osthol, imperatorin, esculetin, scopoletin, umbelliprenin, angelicine, bergamottin, limettin, metoxhalen, aurapten and isopimpinellin are some of these coumarins. This review summarizes the anticancer effects of coumarins and their hybrid molecules including the novel pharmaceutical formulations adding further information on the topic for the last ten years and basically focusing on the structureactivity relationship of these compounds in cancer.

Folic Acid-Doxorubicin-Double-Functionalized-Lipid-Core Nanocapsules: Synthesis, Chemical Structure Elucidation, and Cytotoxicity Evaluation on Ovarian (OVCAR-3) and Bladder (T24) Cancer Cell Lines

PURPOSE

Folic acid-doxorubicin-double-functionalized-lipid-core nanocapsules (LNC-CS-^L-Zn⁺²-DOX-FA) were prepared, characterized, and evaluated in vitro against ovarian and bladder cancer cell lines (OVCAR-3 and T24).

METHODS

LNC-CS-^L-Zn⁺²-DOX-FA was prepared by self-assembly and interfacial reactions, and characterized using liquid chromatography, particle sizing, transmission electron microscopy, and infrared spectroscopy. Cell viability and cellular uptake were studied using MTT assay and confocal microscopy.

RESULTS

The presence of lecithin allows the formation of nanocapsules with a lower tendency of agglomeration, narrower size distributions, and smaller diameters due to an increase in hydrogen bonds at the surface. LNC-^L-CS-Zn⁺²-DOX-FA, containing 98.00 ± 2.34 μg mL^-1 of DOX and 105.00 ± 2.05 μg mL^-1 of FA, had a mean diameter of 123 ± 4 nm and zeta potential of +12.0 ± 1.3 mV. After treatment with LNC-^L-CS-Zn⁺²-DOX-FA (15 μmol L^-1 of DOX), T24 cells had inhibition rates above 80% (24 h) and 90% (48 h), whereas OVCAR-3 cells showed inhibition rates of 68% (24 h) and 93% (48 h), showing higher cytotoxicity than DOX.HCl. The fluorescent-labeled formulation showed a higher capacity of internalization in OVCAR-3 compared to T24 cancer cells.

CONCLUSION

Lecithin favored the increase of hydrogen bonds at the surface, leading to a lower tendency of agglomeration for nanocapsules. LNC-CS-^L-Zn⁺²-DOX-FA is a promising therapeutic agent against tumor-overexpressing folate receptors.

Folate Receptors' Expression in Gliomas May Possess Potential Nanoparticle-Based Drug Delivery Opportunities

Brain cancer effected around estimated 23 890 adults and 3540 children under the age of 15 in 2020. The chemotherapeutic agents that are already approved by the FDA for brain cancer are proving to be not highly effective because of the interference from the tumor microenvironment as well as their own toxicities. Added to this is the impedance presented by the extremely restrictive permeability of the blood brain barrier (BBB). Targeted nanoparticulate drug delivery systems offer a good opportunity to traverse the BBB and selectively target the tumor cells. Folate receptors are found to be one of the most useful targets for drug delivery to the brain. Hence, this Mini-Review discusses the folate receptors and their application in the treatment of brain cancers using targeted nanoparticles.

Hydrophilic Fluorescent Nanoprodrug of Paclitaxel for Glioblastoma Chemotherapy

Highly water-soluble, nontoxic organic nanoparticles on which paclitaxel (PTX), a hydrophobic anticancer drug, has been covalently bound via an ester linkage (4.5% of total weight) have been prepared for the treatment of glioblastoma. These soft fluorescent organic nanoparticles (FONPs), obtained from citric acid and diethylenetriamine by microwave-assisted condensation, show suitable size (Ø = 17-30 nm), remarkable solubility in water, softness as well as strong blue fluorescence in an aqueous environment that are fully retained in cell culture medium. Moreover, these FONPs were demonstrated to show in vitro safety and preferential internalization in glioblastoma cells through caveolin/lipid raft-mediated endocytosis. The PTX-conjugated FONPs retain excellent solubility in water and remain stable in water (no leaching), while they showed anticancer activity against glioblastoma cells in two-dimensional and three-dimensional culture. PTX-specific effects on microtubules reveal that PTX is intracellularly released from the nanocarriers in its active form, in relation with an intracellular-promoted lysis of the ester linkage. As such, these hydrophilic prodrug formulations hold major promise as biocompatible nanotools for drug delivery.

Paclitaxel loaded vitamin E-TPGS nanoparticles for cancer therapy

Localised and targeted potential of nanocarrier for the eminent anticancer agent paclitaxel (PTX) could provide a great platform towards improvement of efficacy with reduction in associated toxicities, whereas incorporation of TPGS could further facilitate delivery in MDR through alteration of its inherent physicochemical properties. Current article therefore puts into perspective on nanocarrier-based recent researches of PTX with special stress towards TPGS-nanoparticle-mediated delivery in the improvement of cancer treatment and then accompanied with the discussion on distinct influence of the fabrication process. Such dynamic fabrications of the nanoparticulate therapy stimulate cellular interaction with frontier area for future research in tumor targeting potential.

Nanomedicine: An effective tool in cancer therapy

Various types of nanoparticles (NPs) have been used in delivering anticancer drugs to the site of action. This area has become more attractive in recent years due to optimal size and negligible undesirable side effects caused by the NPs. The focus of this review is to explore various types of NPs and their surface/chemical modifications as well as attachment of targeting ligands for tuning their properties in order to facilitate targeted delivery to the cancer sites in a rate-controlled manner. Heme compatibility, biodistribution, longer circulation time, hydrophilic lipophilic balance for high bioavailability, prevention of drug degradation and leakage are important in transporting drugs to the targeted cancer sites. The review discusses advantages of polymeric, magnetic, gold, and mesoporous silica NPs in delivering chemotherapeutic agents over the conventional dosage formulations along with their shortcomings/risks and possible solutions/alternatives.

Enhanced and Selective Antiproliferative Activity of Methotrexate-Functionalized-Nanocapsules to Human Breast Cancer Cells (MCF-7)

Methotrexate is a folic acid antagonist and its incorporation into nanoformulations is a promising strategy to increase the drug antiproliferative effect on human breast cancer cells by overexpressing folate receptors. To evaluate the efficiency and selectivity of nanoformulations containing methotrexate and its diethyl ester derivative, using two mechanisms of drug incorporation (encapsulation and surface functionalization) in the in vitro cellular uptake and antiproliferative activity in non-tumoral immortalized human keratinocytes (HaCaT) and in human breast carcinoma cells (MCF-7). Methotrexate and its diethyl ester derivative were incorporated into multiwall lipid-core nanocapsules with hydrodynamic diameters lower than 160 nm and higher drug incorporation efficiency. The nanoformulations were applied to semiconfluent HaCaT or MCF-7 cells. After 24 h, the nanocapsules were internalized into HaCaT and MCF-7 cells; however, no significant difference was observed between the nanoformulations in HaCaT (low expression of folate receptors), while they showed significantly higher cellular uptakes than the blank-nanoformulation in MCF-7, which was the highest uptakes observed for the drug functionalized-nanocapsules. No antiproliferative activity was observed in HaCaT culture, whereas drug-containing nanoformulations showed antiproliferative activity against MCF-7 cells. The effect was higher for drug-surface functionalized nanocapsules. In conclusion, methotrexate-functionalized-nanocapsules showed enhanced and selective antiproliferative activity to human breast cancer cells (MCF-7) being promising products for further in vivo pre-clinical evaluations.

Recent advances in iridium(iii) complex-assisted nanomaterials for biological applications

Phosphorescent iridium(iii) complexes have gained increasing attention in biological applications owing to their excellent photophysical properties and efficient transportation into live cells.

Acetal-linked PEGylated paclitaxel prodrugs forming free-paclitaxel-loaded pH-responsive micelles with high drug loading capacity and improved drug delivery

Endosomal pH-responsive micellar nanoparticles were prepared by self-assembly of an amphiphilic poly(ethylene glycol)-acetal-paclitaxel (PEG-acetal-PTX) prodrug, and free PTX could be encapsulated in the hydrophobic core of the nanoparticles. These nanoparticles exhibited excellent storage stability for over 6months under normal conditions, but disassembled quickly in response to faintly acidic environment. Incorporating physical encapsulation and chemical conjugation, the PTX concentration in the nanoparticles solution could reach as high as 3665μg/mL, accompanying with a high drug loading capacity of 60.3%. Additionally, benefitting from the difference in drug release mechanism and rate between encapsulated PTX and conjugated PTX, a programmed drug release behavior was observed, which may result in higher intracellular drug concentration and longer action time. CCK-8 assays showed that the nanoparticles demonstrated superior antitumor activity than free PTX against both HeLa and MDA-MB-231 cells. These prodrug-based nanomedicines have a great potential in developing translational PTX formulations for cancer therapy.

A poly(amidoamine) dendrimer-based drug carrier for delivering DOX to gliomas cells

G4–FA–PEG/DOX with surface-modified PEG and FA and encapsulated DOX showed enhanced in vitro cytotoxicity and cellular uptake via FR-mediated endocytosis.

Folate receptor-targeted liposomes loaded with a diacid metabolite of norcantharidin enhance antitumor potency for H22 hepatocellular carcinoma both in vitro and in vivo

The diacid metabolite of norcantharidin (DM-NCTD) is clinically effective against hepatocellular carcinoma (HCC), but is limited by its short half-life and high incidence of adverse effects at high doses. We developed a DM-NCTD-loaded, folic acid (FA)-modified, polyethylene glycolated (DM-NCTD/FA-PEG) liposome system to enhance the targeting effect and antitumor potency for HCC at a moderate dose based on our previous study. The DM-NCTD/FA-PEG liposome system produced liposomes with regular spherical morphology, with mean particle size approximately 200 nm, and an encapsulation efficiency >80%. MTT cytotoxicity assays demonstrated that the DM-NCTD/FA-PEG liposomes showed significantly stronger cytotoxicity effects on the H22 hepatoma cell line than did PEG liposomes without the FA modification (P<0.01). We used liquid chromatography–mass spectrometry for determination of DM-NCTD in tissues and tumors, and found it to be sensitive, rapid, and reliable. In addition, the biodistribution study showed that DM-NCTD liposomes improved tumor-targeting efficiency, and DM-NCTD/FA-PEG liposomes exhibited the highest efficiency of the treatments (P<0.01). Meanwhile, the results indicated that although the active liposome group had an apparently increased tumor-targeting efficiency of DM-NCTD, the risk to the kidney was higher than in the normal liposome group. With regard to in vivo antitumor activity, DM-NCTD/FA-PEG liposomes inhibited tumors in H22 tumor-bearing mice better than either free DM-NCTD or DM-NCTD/PEG liposomes (P<0.01), and induced considerably more significant cellular apoptosis in the tumors, with no obvious toxicity to the tissues of model mice or the liver tissue of normal mice, as shown by histopathological examination. All these results demonstrate that DM-NCTD-loaded FA-modified liposomes might have potential application for HCC-targeting therapy.

A review of the ligands and related targeting strategies for active targeting of paclitaxel to tumours

It has been 30 years since the discovery of the anti-tumour property of paclitaxel (PTX), which has been successfully applied in clinic for the treatment of carcinomas of the lungs, breast and ovarian. However, PTX is poorly soluble in water and has no targeting and selectivity to tumour tissue. Recent advances in active tumour targeting of PTX delivery vehicles have addressed some of the issues related to lack of solubility in water and non-specific toxicities associated with PTX. These PTX delivery vehicles are designed for active targeting to specific cancer cells by the addition of ligands for recognition by specific receptors/antigens on cancer cells. This article will focus on various ligands and related targeting strategies serving as potential tools for active targeting of PTX to tumour tissues, illustrating their use in different tumour models. This review also highlights the need of further studies on the discovery of receptors in different cells of specific organ and ligands with binding efficiency to these specific receptors.

The evaluation of cellular uptake efficiency and tumor-targeting ability of MPEG–PDLLA micelles: effect of particle size

The study reported herein describes the cellular uptake efficiency and tumor-targeting ability of MPEG–PDLLA micelles with two different particle sizes.

Enhance Cancer Cell Recognition and Overcome Drug Resistance Using Hyaluronic Acid and α-Tocopheryl Succinate Based Multifunctional Nanoparticles

Multidrug resistance (MDR) presents a clinical obstacle to cancer chemotherapy. The main purpose of this study was to evaluate the potential of a hyaluronic acid (HA) and α-tocopheryl succinate (α-TOS) based nanoparticle to enhance cancer cell recognition and overcome MDR, and to explore the underlying mechanisms. A multifunctional nanoparticle, HTTP-50 NP, consisted of HA-α-TOS (HT) conjugate and d-α-tocopheryl polyethylene glycol succinate (TPGS) with docetaxel loaded in its hydrophobic core. The promoted tumor cell recognition and accumulation, cytotoxicity, and mitochondria-specific apoptotic pathways for the HTTP-50 NP were confirmed in MCF-7/Adr cells (P-gp-overexpressing cancer model), indicating that the formulated DTX and the conjugated α-TOS in the HTTP-50 NP could synergistically circumvent the acquired and intrinsic MDR in MCF-7/Adr cells. In vivo investigation on the MCF-7/Adr xenografted nude mice models confirmed that HTTP-50 NP possessed much higher tumor tissue accumulation and exhibited pronouncedly enhanced antiresistance tumor efficacy with reduced systemic toxicity compared with HTTP-0 NP and Taxotere. The mechanisms of the multifunctional HTTP-50 NP to overcome MDR and enhance antiresistance efficacy may be contributed by CD44 receptor-targeted delivery and P-gp efflux inhibition, and meanwhile to maximize antitumor efficacy by synergism of DTX and mitocan of α-TOS killing tumor cells.

Design of magnetic nanoparticles for hepatocellular carcinoma treatment using the control mechanisms of the cell internal nucleus and external membrane

Nanoparticle drugs and relevant treatment technologies have achieved widespread attention in recent years. Hepatocellular carcinoma (HCC) remains a challenging malignancy of worldwide importance since it is one of the worst malignant tumors. In this study, magnetic Fe₃O₄ nanoparticles are prepared via a co-precipitation reaction with self-assembled surface monolayers of oleic acid molecules. For synthesizing the nanoparticle anti-tumor drug used against HCC, the liquid photo-immobilization method is used to bond the photoactive N-isopropylacrylamide derivative (NIPAm-AA) onto the oleic acid monolayer for subsequently embedding doxorubicin, photoactive tumor necrosis factor-α (TNF-α)/interferon-γ (IFN-γ), and folic acid (FOL). We investigate how the nanoparticle drug inhibits the growth of human hepatocellular carcinoma HepG2 cells in vitro and in vivo. Remarkably, our characterizations show that the nanoparticle drug demonstrates much higher anticancer efficacy (94.7%) in vitro than previously reported drugs. It is revealed that the programmed cell death induced by the drug is mainly oncosis, a new programmed cell death pathway, different from earlier proposed mechanisms. This oncosis mechanism is also confirmed in the other two hepatocellular carcinoma cells (BEL-7402 and Huh-7). This study may be helpful for developing a new type of nanoparticle drug capable of assuring molecular control of both the cell inner nucleus and outer membrane as a means to enormously increase the drug efficacy in human hepatocellular carcinoma.

Controllable organization and high throughput production of recoverable 3D tumors using pneumatic microfluidics

Three-dimensional tumor culture methods offer a high degree of biological and clinical relevance to in vitro models as well as cancer therapy. However, a straightforward, dynamic, and high-throughput method for micro-manipulation of 3D tumors is not yet well established. In this study, we present a novel and simple strategy for producing biomimetic 3D tumors in a controllable, high throughput manner based on an integrated microfluidic system with well-established pneumatic microstructures. Serial manipulations, including one-step cell localization, array-like self-assembly, and real-time analysis of 3D tumors, are accomplished smoothly in the microfluidic device. The recovery of tumor products from the chip is performed by dynamic off-switch of the pneumatic microstructures. In addition, this microfluidic platform is demonstrated to be capable of producing multiple types of 3D tumors and performing the evaluation of tumor targeting by nanomedicine. The pneumatic microfluidic-based 3D tumor production shows potential for research on tumor biology, tissue engineering, and drug delivery.

Aptamer–conjugated graphene oxide–gold nanocomposites for targeted chemo-photothermal therapy of cancer cells

The multifunctional GO–Au–aptamer nanocomposites were successfully constructed. They can be used as an excellent drug-delivery system for targeted chemo-photothermal therapy for cancer cells.

Multivalent polymers for drug delivery and imaging: the challenges of conjugation

Multivalent polymers offer a powerful opportunity to develop theranostic materials on the size scale of proteins that can provide targeting, imaging, and therapeutic functionality. Achieving this goal requires the presence of multiple targeting molecules, dyes, and/or drugs on the polymer scaffold. This critical review examines the synthetic, analytical, and functional challenges associated with the heterogeneity introduced by conjugation reactions as well as polymer scaffold design. First, approaches to making multivalent polymer conjugations are discussed followed by an analysis of materials that have shown particular promise biologically. Challenges in characterizing the mixed ligand distributions and the impact of these distributions on biological applications are then discussed. Where possible, molecular-level interpretations are provided for the structures that give rise to the functional ligand and molecular weight distributions present in the polymer scaffolds. Lastly, recent strategies employed for overcoming or minimizing the presence of ligand distributions are discussed. This review focuses on multivalent polymer scaffolds where average stoichiometry and/or the distribution of products have been characterized by at least one experimental technique. Key illustrative examples are provided for scaffolds that have been carried forward to in vitro and in vivo testing with significant biological results.

Powerful inner/outer controlled multi-target magnetic nanoparticle drug carrier prepared by liquid photo-immobilization

Nanomagnetic materials offer exciting avenues for advancing cancer therapies. Most researches have focused on efficient delivery of drugs in the body by incorporating various drug molecules onto the surface of nanomagnetic particles. The challenge is how to synthesize low toxic nanocarriers with multi-target drug loading. The cancer cell death mechanisms associated with those nanocarriers remain unclear either. Following the cell biology mechanisms, we develop a liquid photo-immobilization approach to attach doxorubicin, folic acid, tumor necrosis factor-α, and interferon-γ onto the oleic acid molecules coated Fe3O4 magnetic nanoparticles to prepare a kind of novel inner/outer controlled multi-target magnetic nanoparticle drug carrier. In this work, this approach is demonstrated by a variety of structural and biomedical characterizations, addressing the anti-cancer effects in vivo and in vitro on the HeLa, and it is highly efficient and powerful in treating cancer cells in a valuable programmed cell death mechanism for overcoming drug resistance.

Folate-targeted paclitaxel-conjugated polymeric micelles inhibits pulmonary metastatic hepatoma in experimental murine H22 metastasis models

Hepatocellular carcinoma shows low response to most conventional chemotherapies; additionally, extrahepatic metastasis from hepatoma is considered refractory to conventional systemic chemotherapy. Target therapy is a promising strategy for advanced hepatoma; however, targeted accumulation and controlled release of therapeutic agents into the metastatic site is still a great challenge. Folic acid (FA) and paclitaxel (PTX) containing composite micelles (FA-M[PTX]) were prepared by coassembling the FA polymer conjugate and PTX polymer conjugate. The main purpose of this study is to investigate the inhibitory efficacy of FA-M(PTX) on the pulmonary metastasis of intravenously injected murine hepatoma 22 (H22) on BALB/c mice models. The lung metastatic burden of H22 were measured and tissues were analyzed by immunohistochemistry and histology (hematoxylin and eosin stain), followed by survival analysis. The results indicated that FA-M(PTX) prevented pulmonary metastasis of H22, and the efficacy was stronger than pure PTX and simple PTX-conjugated micelles. In particular, the formation of lung metastasis colonies in mice was evidently inhibited, which was paralleled with the downregulated expression of matrix metalloproteinase-2 and matrix metalloproteinase-9. Furthermore, the mice bearing pulmonary metastatic hepatoma in the FA-M(PTX) group gained significantly prolonged survival time when compared with others given equivalent doses of PTX of 30 mg/kg. The enhanced efficacy of FA-M(PTX) is theoretically ascribed to the target effect of FA; moreover, the extensive pulmonary capillary networks may play a role. In conclusion, FA-M(PTX) displayed great potential as a promising antimetastatic agent, and the FA-conjugated micelles is a preferential targeted delivery system when compared to micelles without FA.

Polymersomes conjugated with des-octanoyl ghrelin and folate as a BBB-penetrating cancer cell-targeting delivery system

Chemotherapy for brain cancer tumors remains a big challenge for clinical medicine due to the inability to transport sufficient drug across the blood-brain barrier (BBB) and the poor penetration of drug into the tumors. To effectively treat brain tumors and reduce side effects on normal tissues, both des-octanoyl ghrelin and folate conjugated with polymersomal doxorubicin (GFP-D) was developed in this study to help transport across the BBB and target the tumor as well. The size measurements revealed that this BBB-penetrating cancer cell-targeting GFP-D was about 85 nm. In-vitro experiments with a BBB model and C6 glioma cells demonstrated that GFP-D owned a robust penetrating-targeting function for drug delivery. In C6 cell viability tests, GFP-D exhibited an inhibitory effect significantly different from the unmodified polymersomal doxorubicin (P-D). In-vivo antitumor experiments showed that GFP-D performed a much better anti-glioma effect and presented a significant improvement in the overall survival of the tumor-bearing mice as compared to the treatments with free doxorubicin (Dox), liposomal doxorubicin (L-D), P-D, or single ligand conjugated P-D. In addition, Cy 5.5 was used as a probe to investigate the delivery property of this penetrating-targeting delivery system. The overall experimental results indicate that this BBB-penetrating cancer cell-targeting GFP is a highly potential nanocarrier for the treatment of brain tumors.

Preparation, characterization, and antitumor activities of folate-decorated docetaxel-loaded human serum albumin nanoparticles

CONTEXT

Docetaxel is now a major antitumor drug in clinical use for the treatment of a variety of tumors. The ethanol/Tween 80 solvent required in the formulation to increase the docetaxel solubility is at least partly responsible for the hypersensitivity reaction, decreased uptake by tumor tissue, and increased exposure to other body compartments.

OBJECTIVE

The present study was aimed at developing hydrosoluble DTX-FA-HSANPs targeting tumor cells and to investigate antitumor activities of the nanoparticles.

MATERIALS AND METHODS

The DTX-HSANPs were prepared using a desolvation technique and the carboxylic groups of NHS-folate were conjugated with the amino groups of the human serum albumin nanoparticles, and studied their size and zeta potential, drug loading efficiency, surface morphology, release properties in vitro, and antitumor activities.

RESULTS

The spherical nanoparticles obtained were negatively charged with a zeta potential of about -30 mV and characterized around 150 nm with a narrow size distribution. Drug loading efficiency was approximately 17.2%. The folate-decorated nanoparticles targeted a human hepatoma cell line effectively. The in vitro drug release of DTX-FA-HSANPs in the first 96 h corresponded with the following equation: Q = 18.87851 - 0.13866t + 0.21276t² - 0.00704t³ + 0.0000847854t⁴ - 0.00000034991t⁵ (R² = 0.98155). Moreover, the in vitro antitumor activities of DTX-FA-HSANPs were close to the activities of the positive control (docetaxel). The in vivo inhibition ratios of DTX-FA-HSANPs and docetaxel were 66.2% and 59.5%, respectively, at a dose of 5 mg/kg.

DISCUSSION AND CONCLUSION

In light of the observed antitumor activities, it would be of considerable interest to collect sufficient data for the clinical application of docetaxel-loaded nanoparticles.

Application of nanoparticles on diagnosis and therapy in gliomas

Glioblastoma multiforme (GBM) is one of the most deadly diseases that affect humans, and it is characterized by high resistance to chemotherapy and radiotherapy. Its median survival is only fourteen months, and this dramatic prognosis has stilled without changes during the last two decades; consequently GBM remains as an unsolved clinical problem. Therefore, alternative diagnostic and therapeutic approaches are needed for gliomas. Nanoparticles represent an innovative tool in research and therapies in GBM due to their capacity of self-assembly, small size, increased stability, biocompatibility, tumor-specific targeting using antibodies or ligands, encapsulation and delivery of antineoplastic drugs, and increasing the contact surface between cells and nanomaterials. The active targeting of nanoparticles through conjugation with cell surface markers could enhance the efficacy of nanoparticles for delivering several agents into the tumoral area while significantly reducing toxicity in living systems. Nanoparticles can exploit some biological pathways to achieve specific delivery to cellular and intracellular targets, including transport across the blood-brain barrier, which many anticancer drugs cannot bypass. This review addresses the advancements of nanoparticles in drug delivery, imaging, diagnosis, and therapy in gliomas. The mechanisms of action, potential effects, and therapeutic results of these systems and their future applications in GBM are discussed.

Multifunctional mesoporous silica-coated graphene nanosheet used for chemo-photothermal synergistic targeted therapy of glioma

Current therapy of malignant glioma in clinic is unsatisfactory with poor patient compliance due to low therapeutic efficiency and strong systemic side effects. Herein, we combined chemo-photothermal targeted therapy of glioma within one novel multifunctional drug delivery system. A targeting peptide (IP)-modified mesoporous silica-coated graphene nanosheet (GSPI) was successfully synthesized and characterized, and first introduced to the drug delivery field. A doxorubicin (DOX)-loaded GSPI-based system (GSPID) showed heat-stimulative, pH-responsive, and sustained release properties. Cytotoxicity experiments demonstrated that combined therapy mediated the highest rate of death of glioma cells compared to that of single chemotherapy or photothermal therapy. Furthermore, the IP modification could significantly enhance the accumulation of GSPID within glioma cells. These findings provided an excellent drug delivery system for combined therapy of glioma due to the advanced chemo-photothermal synergistic targeted therapy and good drug release properties of GSPID, which could effectively avoid frequent and invasive dosing and improve patient compliance.