Lipidic Cubic-Phase Nanoparticles-Cubosomes for Efficient Drug Delivery to Cancer Cells

Cubosomes as versatile lipid nanocarriers for neurological disorder therapeutics: a comprehensive review

Cubosomes are novel vesicular drug delivery systems with lipidic liquid crystal nanoparticles formed of predetermined proportions of amphiphilic lipids. They have a honeycomb-like structure and are thermodynamically stable. These bicontinuous lipid layers are separated into two water-based channels internally that can be used by various bioactive substances, including drugs, proteins, and peptides. This complex structure is responsible for its high drug-loading capacity. Cubosomes are thought to be promising vehicles for various routes of administration because of their extraordinary characteristics, including bioadhesion, the capacity to encapsulate hydrophilic, and hydrophobic, as well as amphiphilic substances, high resistance to environmental stress, and their ability to achieve controlled release through modification. One of the essential elements for improving patient compliance is the ability of these well-defined nano-drug delivery systems to boost the effectiveness of targeting while lowering the side effects/toxicities of payloads. The large internal surface area, a sufficiently uncomplicated fabrication procedure, and biodegradability make it an attractive nano lipid carrier for drug delivery. This review outlines the recent advancement of cubosomes for managing various neurological disorders, highlighting their potential in this field.

Small-angle X-ray and neutron scattering applied to lipid-based nanoparticles: Recent advancements across different length scales

Lipid-based nanoparticles (LNPs), ranging from nanovesicles to non-lamellar assemblies, have gained significant attention in recent years, as versatile carriers for delivering drugs, vaccines, and nutrients. Small-angle scattering methods, employing X-rays (SAXS) or neutrons (SANS), represent unique tools to unveil structure, dynamics, and interactions of such particles on different length scales, spanning from the nano to the molecular scale. This review explores the state-of-the-art on scattering methods applied to unveil the structure of lipid-based nanoparticles and their interactions with drugs and bioactive molecules, to inform their rational design and formulation for medical applications. We will focus on complementary information accessible with X-rays or neutrons, ranging from insights on the structure and colloidal processes at a nanoscale level (SAXS) to details on the lipid organization and molecular interactions of LNPs (SANS). In addition, we will review new opportunities offered by Time-resolved (TR)-SAXS and -SANS for the investigation of dynamic processes involving LNPs. These span from real-time monitoring of LNPs structural evolution in response to endogenous or external stimuli (TR-SANS), to the investigation of the kinetics of lipid diffusion and exchange upon interaction with biomolecules (TR-SANS). Finally, we will spotlight novel combinations of SAXS and SANS with complementary on-line techniques, recently enabled at Large Scale Facilities for X-rays and neutrons. This emerging technology enables synchronized multi-method investigation, offering exciting opportunities for the simultaneous characterization of the structure and chemical or mechanical properties of LNPs.

Cubosomal nanoformulation increase invitro dissolution and anticancer activity of Fisetin in A549 lung cancer cells

Aim: To prepare fisetin (FIS) cubosomal nanoformulation to increase aqueous solubility and anticancer activity. Methods: Top-down method using glyceryl monooleate (GMO) and Pluronic F-127. Results: Optimized using 2% GMO and 1% Pluronic F-127, reported 93.07 nm particle size, 80.10% drug entrapment, and reports more than 50% enhanced in vitro drug release than native FIS. MTT assay reports IC50 Values of FIS 16.59 μg/ml and optimized cubosomal FIS nanoformulation (FISCUB) 12.18 μg/ml. The colony numbers observed in clonogenic assay for FISCUB were 8.33 ± 0.58 and FIS 11.67 ± 1.15. In flow cytometry study, apoptotic cells in FISCUB and FIS-treated A549 cells were found to be 33.4 and 6.83% respectively. Conclusion: A stable cubosomal nanoformulation of FIS showed enhanced aqueous solubility and anticancer activity.

Angiopep-2-Functionalized Lipid Cubosomes for Blood-Brain Barrier Crossing and Glioblastoma Treatment

Glioblastoma multiforme (GBM) is an aggressive brain cancer with high malignancy and resistance to conventional treatments, resulting in a bleak prognosis. Nanoparticles offer a way to cross the blood-brain barrier (BBB) and deliver precise therapies to tumor sites with reduced side effects. In this study, we developed angiopep-2 (Ang2)-functionalized lipid cubosomes loaded with cisplatin (CDDP) and temozolomide (TMZ) for crossing the BBB and providing targeted glioblastoma therapy. Developed lipid cubosomes showed a particle size of around 300 nm and possessed an internal ordered inverse primitive cubic phase, a high conjugation efficiency of Ang2 to the particle surface, and an encapsulation efficiency of more than 70% of CDDP and TMZ. In vitro models, including BBB hCMEC/D3 cell tight monolayer, 3D BBB cell spheroid, and microfluidic BBB/GBM-on-a-chip models with cocultured BBB and glioblastoma cells, were employed to study the efficiency of the developed cubosomes to cross the BBB and showed that Ang2-functionalized cubosomes can penetrate the BBB more effectively. Furthermore, Ang2-functionalized cubosomes showed significantly higher uptake by U87 glioblastoma cells, with a 3-fold increase observed in the BBB/GBM-on-a-chip model as compared to that of the bare cubosomes. Additionally, the in vivo biodistribution showed that Ang2 modification could significantly enhance the brain accumulation of cubosomes in comparison to that of non-functionalized particles. Moreover, CDDP-loaded Ang2-functionalized cubosomes presented an enhanced toxic effect on U87 spheroids. These findings suggest that the developed Ang2-cubosomes are prospective for improved BBB crossing and enhanced delivery of therapeutics to glioblastoma and are worth pursuing further as a potential application of nanomedicine for GBM treatment.

Versatile Nanoparticulate Systems as a Prosperous Platform for Targeted Nose-Brain Drug Delivery

The intranasal route has proven to be a reliable and promising route for delivering therapeutics to the central nervous system (CNS), averting the blood-brain barrier (BBB) and avoiding extensive first-pass metabolism of some drugs, with minimal systemic exposure. This is considered to be the main problem associated with other routes of drug delivery such as oral, parenteral, and transdermal, among other administration methods. The intranasal route maximizes drug bioavailability, particularly those susceptible to enzymatic degradation such as peptides and proteins. This review will stipulate an overview of the intranasal route as a channel for drug delivery, including its benefits and drawbacks, as well as different mechanisms of CNS drug targeting using nanoparticulate drug delivery systems devices; it also focuses on pharmaceutical dosage forms such as drops, sprays, or gels via the nasal route comprising different polymers, absorption promoters, CNS ligands, and permeation enhancers.

Cubosomes: An Emerging and Promising Drug Delivery System for Enhancing Cancer Therapy

Cancer and other diseases can be treated with cubosomes, which are lyotropic nonlamellar liquid crystalline nanoparticles (LCNs). These cubosomes can potentially be a highly versatile carrier with theranostic efficacy, as they can be ingested, applied topically, or injected intravenously. Recent years have seen substantial progress in the synthesis, characterization, regulation of drug release patterns, and target selectivity of loaded anticancer bioactive compounds. However, its use in clinical settings has been slow and necessitates additional proof. Recent progress and roadblocks in using cubosomes as a nanotechnological intervention against various cancers are highlighted. In the last few decades, advances in biomedical nanotechnology have allowed for the development of "smart" drug delivery devices that can adapt to external stimuli. By improving therapeutic targeting efficacy and lowering the negative effects of payloads, these well-defined nanoplatforms can potentially promote patient compliance in response to specific stimuli. Liposomes and niosomes, two other well-known vesicular systems, share a lipid basis with cubosomes. Possible applications include a novel medication delivery system for hydrophilic, lipophilic, and amphiphilic drugs. We evaluate the literature on cubosomes, emphasizing their potential use in tumor-targeted drug delivery applications and critiquing existing explanations for cubosome self-assembly, composition, and production. As cubosome dispersion has bioadhesive and compatible features, numerous drug delivery applications, including oral, ocular, and transdermal, are also discussed in this review.

Optimization of hyaluronan-enriched cubosomes for bromfenac delivery enhancing corneal permeation: characterization, ex vivo, and in vivo evaluation

To design and evaluate hyaluronan-based cubosomes loaded with bromfenac sodium (BS) for ocular application to enhance the corneal permeation and retention in pterygium and cataract treatment. BS-loaded cubosomes were prepared by the emulsification method, employing 2³ full factorial design using Design-Expert® software. Glycerol monoolein (GMO) and poloxamer 407 (P407) as lipid phase and polyvinyl alcohol (PVA) as stabilizer were the used ingredients. The optimized formulation (OBC; containing GMO (7% w/w), P407 (0.7% w/w) and PVA (2.5% w/w)) was further evaluated. OBC had an entrapment efficiency of 61.66 ± 1.01%, a zeta potential of -30.80 ± 0.61 mV, a mean particle size of 149.30 ± 15.24 nm and a polydispersity index of 0.21 ± 0.02. Transmission electron microscopy confirmed its cubic shape and excellent dispersibility. OBC exhibited high stability and no ocular irritation that was ensured by histopathology. Ex vivo permeation study showed a significant increase in drug deposition and permeability parameters through goat cornea, besides, confocal laser microscopy established the superior permeation capability of OBC, as compared to drug solution. In vivo pharmacokinetics in aqueous humor indicated higher AUC_0-tlast (18.88 µg.h/mL) and mean residence time (3.16 h) of OBC when compared to the marketed eye drops (7.93 µg.h/mL and 1.97 h, respectively). Accordingly, hyaluronan-enriched cubosomes can be regarded as a promising carrier for safe and effective topical ocular delivery.

Oral Drug Delivery via Intestinal Lymphatic Transport Utilizing Lipid-Based Lyotropic Liquid Crystals

Lyotropic liquid crystals (LLCs) are liquids that have crystalline structures. LLCs as drug delivery systems that can deliver hydrophobic, hydrophilic, and amphiphilic agents. Due to their unique phases and structures, LLCs can protect both small molecules and biologics from the gastrointestinal tract's harsh environment, thus making LLCs attractive as carriers for oral drug delivery. In this review, we discuss the advantages of LLCs and LLCs as oral formulations targeting intestinal lymphatic transport. In oral LLC formulations, the relationship between the micelle compositions and the resulting LLC structures as well as intestinal transport and absorption were determined. In addition, we further demonstrated approaches for the enhancement of intestinal lymphatic transport: (1) lipid-based LLCs promoting chylomicron secretion and (2) the design of LLC nanoparticles with M cell-triggered ligands for targeting the M cell pathway. In this review, we introduce LLC drug delivery systems and their characteristics. Our review focuses on recent approaches using oral LLC drug delivery strategies targeting the intestinal lymphatic system to enhance drug bioavailability.

Lyotropic liquid crystalline 2D and 3D mesophases: Advanced materials for multifunctional anticancer nanosystems

Cancer remains a leading cause of mortality. Despite significant breakthroughs in conventional therapies, treatment is still far from ideal due to high toxicity in normal tissues and therapeutic inefficiency caused by short drug lifetime in the body and resistance mechanisms. Current research moves towards the development of multifunctional nanosystems for delivery of chemotherapeutic drugs, bioactives and/or radionuclides that can be combined with other therapeutic modalities, like gene therapy, or imaging to use in therapeutic screening and diagnosis. The preparation and characterization of Lyotropic Liquid Crystalline (LLC) mesophases self-assembled as 2D and 3D structures are addressed, with an emphasis on the unique properties of these nanoassemblies. A comprehensive review of LLC nanoassemblies is also presented, highlighting the most recent advances and their outstanding advantages as drug delivery systems, including tailoring strategies that can be used to overcome cancer challenges. Therapeutic agents loaded in LLC nanoassemblies offer qualitative and quantitative enhancements that are superior to conventional chemotherapy, particularly in terms of preferential accumulation at tumor sites and promoting enhanced cancer cell uptake, lowering tumor volume and weight, improving survival rates, and increasing the cytotoxicity of their loaded therapeutic agents. In terms of quantitative anticancer efficacy, loaded LLC nanoassemblies reduced the IC50 values from 1.4-fold against lung cancer cells to 125-fold against ovarian cancer cells.

Assessing Drug Administration Techniques in Zebrafish Models of Neurological Disease

Neurological diseases, including neurodegenerative and neurodevelopmental disorders, affect nearly one in six of the world's population. The burden of the resulting deaths and disability is set to rise during the next few decades as a consequence of an aging population. To address this, zebrafish have become increasingly prominent as a model for studying human neurological diseases and exploring potential therapies. Zebrafish offer numerous benefits, such as genetic homology and brain similarities, complementing traditional mammalian models and serving as a valuable tool for genetic screening and drug discovery. In this comprehensive review, we highlight various drug delivery techniques and systems employed for therapeutic interventions of neurological diseases in zebrafish, and evaluate their suitability. We also discuss the challenges encountered during this process and present potential advancements in innovative techniques.

Cubic nanoparticles as potential carriers for a natural anticancer drug: development, in vitro and in vivo characterization

Natural compounds that elicit anticancer properties are of great interest for cancer therapy. However, the low solubility and bioavailability of these compounds limit their use as efficient anticancer drugs. To avoid these drawbacks, incorporation of these compounds into cubic nanoparticles (cubosomes) was carried out. Cubosomes containing bergapten which is a natural anticancer compound isolated from Ficus carica were prepared by the homogenization technique using monoolein and poloxamer. These cubosomes were characterized for size, zeta potential, entrapment efficiency, small angle X-ray diffraction, in vitro release, in vitro cytotoxicity, cellular uptake, and antitumor activity. Particle size of cubosomes was 220 ± 3.6 nm with almost neutral zeta potential - 5 ± 1.2 mV and X-ray measurements confirmed the existence of the cubic structure. Additionally, more than 90% of the natural anticancer drug was entrapped within the cubosomes. A sustained release over 30 h was obtained for these cubosomes. Finally, these cubosomes illustrated higher in vitro cytotoxicity and in vivo tumor inhibition compared with the free natural anticancer compound. Thus, cubosomes could be promising carriers for enhancement of antitumor efficiency of this natural compound.

Hybrids of manganese oxide and lipid liquid crystalline nanoparticles (LLCNPs@MnO) as potential magnetic resonance imaging (MRI) contrast agents

Due to the health risks associated with the use of Gd-chelates and the promising effects of using nanoparticles as T1 contrast agents (CAs) for MRI, Mn-based nanoparticles are considered a highly competitive alternative. The use of hybrid constructs with paramagnetic functionality of Mn-based nanoparticles is an effective approach, in particular, the use of biocompatible lipid liquid crystalline nanoparticles (LLCNPs) as a carrier of MnO nanoparticles. LLCNPs possess a unique internal structure ensuring a payload of different polarity MnO nanoparticles. In view of MRI application, the surface properties including the polarity of MnO are crucial factors determining their relaxation rate and thus the MRI efficiency. Two novel hybrid constructs consisting of LLCNPs loaded with hydrophobic MnO-oleate and hydrophilic MnO-DMSA NPs were prepared. These nanosystems were studied in terms of their physico-chemical properties, positive T1 contrast enhancement properties (in vitro and in vivo) and biological safety. LLCNPs@MnO-oleate and LLCNPs@MnO-DMSA hybrids exhibited a heterogeneous phase composition, however with differences in the inner periodic arrangement and structural parameters, as well as in the preferable localization of MnO NPs within the LLCNPs. Also, these hybrids differed in terms of particle size-related parameters and colloidal stability, which was found to be strongly dependent on the addition of differently functionalized MnO NPs. Embedding both types of MnO NPs into LLCNPs resulted in high relaxivity parameters, in comparison to bare MnO-DMSA NPs and also commercially developed CAs (e.g. Dotarem and Teslascan). Further biosafety studies revealed that cell internalization pathways were dependent on the prepared hybrid type, while viability, effects on the mitochondria membrane potential and cytoskeletal networks were rather related to the susceptibility of the particular cell line. The high relaxation rates achieved with the developed hybrid LLCNPs@MnO enable them to be possibly used as novel and biologically safe MRI T1-enhancing CAs in in vivo imaging.

Comparative study on the performance of monoolein cubic nanoparticles and trimyristin solid lipid nanoparticles as carriers for docetaxel

Nowadays the application of lipid nanoparticles as carriers for the delivery of anticancer drugs gained great attention in cancer therapy. Solid lipid nanoparticles (SLN_s) and cubic nanoparticles (cubosomes) are considered as promising carriers in cancer therapy. The comparison of these two lipid nanoparticles as efficient carriers for the anticancer drug docetaxel was our main goal in this study. Both nanoparticles were prepared by the hot melt homogenization technique followed by measurement of particle size, zeta potential, entrapment efficiency and in vitro release of docetaxel. An advanced technique has been applied to measure the release of docetaxel from these nanoparticles using small unilamellar vesicles (SUV_s) as acceptor particles which resemble many compartments in our body. All prepared nanoparticles revealed a neutral zeta potential with particle sizes of about 200 nm. While SUV_s showed a negative surface charge with a zeta potential of -55 mV, cubosomes showed higher entrapment efficiency and a slower docetaxel release compared to SLN_s. Additionally, cubosomes improved in vitro cytotoxicity as well as the in vivo antitumor inhibition of docetaxel compared to SLN_s and docetaxel solution. Overall, our results showed that incorporation of docetaxel into cubosomes could enhance its in vitro and in vivo performance compared to docetaxel incorporated into SLN_s.

Interaction of polyelectrolyte-shell cubosomes with serum albumin for triggering drug release in gastrointestinal cancer

Nano-structured and functionalized materials for encapsulation, transport, targeting and controlled release of drugs are of high interest to overcome low bioavailability in oral administration. We develop lipid-based cubosomes, which are surface-functionalized with biocompatible chitosan-N-arginine and alginate, displaying internal liquid crystalline structures. Polyelectrolyte-shell (PS) cubosomes have pH-responsive characteristics profitable for oral delivery. The obtained PScubosomes can strongly interact with serum albumin, a protein which is released in the stomach under gastric cancer conditions. An effective thermodynamic PScubosome-protein interaction was characterized at pH 2.0 and 7.4 by isothermal titration calorimetry at 37 °C. A high increment of the albumin conformation transition temperature was evidenced by differential scanning calorimetry upon incubation with PScubosomes. The performed structural studies by synchrotron small-angle X-ray scattering (SAXS) revealed essential alterations in the internal liquid crystalline topology of the nanocarriers including an Im3m to Pn3m transition and a reduction of the cubic lattice parameters. The PScubosome nanoparticle interaction with serum albumin, leading to inner structural changes in a range of temperatures, promoted the release of water from the cubosomal nanochannels. Altogether, the results revealed effective interactions of the PScubosomes with albumin under simulated gastrointestinal pH conditions and suggested promising nanocarrier characteristics for triggered oral drug release.

Protein adsorption determines pulmonary cell uptake of lipid-based nanoparticles

The inhalable administration of lipid nanoparticles is an effective strategy for localised delivery of therapeutics against various lung diseases. Of this, improved intracellular delivery of pharmaceuticals for infectious disease and cancer management is of high significance. However, the influence of lipid nanoparticle composition and structure on uptake in pulmonary cell lines, especially in the presence of biologically relevant media is poorly understood. Here, the uptake of lamellar (liposomes) versus non-lamellar (cubosomes) lipid nanoparticles in macrophages and lung epithelial cells was quantified and the influence of bronchoalveolar lavage fluid (BALF), containing native pulmonary protein and surfactant molecules is determined. Cubosome uptake in both macrophages and epithelial cells was strongly mediated by a high percentage of molecular function regulatory and binding proteins present within the protein corona. In contrast, the protein corona did not influence the uptake of liposomes in epithelial cells. In macrophages, the proteins mediated a rapid internalisation, followed by exocytosis of liposomes after 6 h incubation. These findings on the influence of biological fluid in regulating lipid nanoparticle uptake mechanisms may guide future development of optimal intracellular delivery systems for therapeutics via the pulmonary route.

Doxorubicin- and Trastuzumab-Modified Gold Nanoparticles as Potential Multimodal Agents for Targeted Therapy of HER2+ Cancers

Recently, targeted nanoparticles (NPs) have attracted much attention in cancer treatment due to their high potential as carriers for drug delivery. In this article, we present a novel bioconjugate (DOX–AuNPs–Tmab) consisting of gold nanoparticles (AuNPs, 30 nm) attached to chemotherapeutic agent doxorubicin (DOX) and a monoclonal antibody, trastuzumab (Tmab), which exhibited specific binding to HER2 receptors. The size and shape of synthesized AuNPs, as well as their surface modification, were analyzed by the TEM (transmission electron microscopy) and DLS (dynamic light scattering) methods. Biological studies were performed on the SKOV-3 cell line (HER2+) and showed high specificity of binding to the receptors and internalization capabilities, whereas MDA-MB-231 cells (HER2−) did not. Cytotoxicity experiments revealed a decrease in the metabolic activity of cancer cells and surface area reduction of spheroids treated with DOX–AuNPs–Tmab. The bioconjugate induced mainly cell cycle G2/M-phase arrest and late apoptosis. Our results suggest that DOX–AuNPs–Tmab has great potential for targeted therapy of HER2-positive tumors.

Recent Progress of Lipid Nanoparticles-Based Lipophilic Drug Delivery: Focus on Surface Modifications

Numerous drugs have emerged to treat various diseases, such as COVID-19, cancer, and protect human health. Approximately 40% of them are lipophilic and are used for treating diseases through various delivery routes, including skin absorption, oral administration, and injection. However, as lipophilic drugs have a low solubility in the human body, drug delivery systems (DDSs) are being actively developed to increase drug bioavailability. Liposomes, micro-sponges, and polymer-based nanoparticles have been proposed as DDS carriers for lipophilic drugs. However, their instability, cytotoxicity, and lack of targeting ability limit their commercialization. Lipid nanoparticles (LNPs) have fewer side effects, excellent biocompatibility, and high physical stability. LNPs are considered efficient vehicles of lipophilic drugs owing to their lipid-based internal structure. In addition, recent LNP studies suggest that the bioavailability of LNP can be increased through surface modifications, such as PEGylation, chitosan, and surfactant protein coating. Thus, their combinations have an abundant utilization potential in the fields of DDSs for carrying lipophilic drugs. In this review, the functions and efficiencies of various types of LNPs and surface modifications developed to optimize lipophilic drug delivery are discussed.

Anti-Tumor Activity of Orally Administered Gefitinib-Loaded Nanosized Cubosomes against Colon Cancer

Gefitinib (GFT) is a tyrosine kinase inhibitor drug used as a first-line treatment for patients with advanced or metastatic non-small cell lung, colon, and breast cancer. GFT exhibits low solubility and hence low oral bioavailability, which restricts its clinical application. One of the most important trends in overcoming such problems is the use of a vesicular system. Cubosomes are considered one of the most important vesicular systems used to improve solubility and oral bioavailability. In this study, GFT cubosomal nanoparticles (GFT-CNPs) were prepared by the emulsification method. The selected formulation variables were analyzed and optimized by full factorial design and response surface methodology. Drug entrapment efficiency (EE%), transmission electron microscopy, particle size, polydispersity index, in vitro release and its kinetics, and the effect of storage studies were estimated. The chosen GFT-CNPs were subjected to further investigations as gene expression levels of tissue inhibitors of metalloproteinases-1 (TIMP-1) and matrix metalloproteinases-7 (MMP-7), colon biomarkers, and histopathological examination of colon tissues. The prepared GFT-CNPs were semi-cubic in shape, with high EE%, smaller vesicle size, and higher zeta potential values. The in vivo data showed a significant decrease in the serum level of embryonic antigen (CEA), carbohydrate antigen 19-9 (CA 19-9), and gene expression level of TIMP-1 and MMP-7. Histopathological examination showed enhancement in cancer tissue and highly decreased focal infiltration in the lamina propria after treatment with GFT-CNPs.

pH-Responsive Hybrid Nanoassemblies for Cancer Treatment: Formulation Development, Optimization, and In Vitro Therapeutic Performance

Current needs for increased drug delivery carrier efficacy and specificity in cancer necessitate the adoption of intelligent materials that respond to environmental stimuli. Therefore, we developed and optimized pH-triggered drug delivery nanoassemblies that exhibit an increased release of doxorubicin (DOX) in acidic conditions typical of cancer tissues and endosomal vesicles (pH 5.5) while exhibiting significantly lower release under normal physiological conditions (pH 7.5), indicating the potential to reduce cytotoxicity in healthy cells. The hybrid (polymeric/lipid) composition of the lyotropic non-lamellar liquid crystalline (LNLCs) nanoassemblies demonstrated high encapsulation efficiency of the drug (>90%) and high drug loading content (>7%) with colloidal stability lasting at least 4 weeks. Confocal microscopy revealed cancer cellular uptake and DOX-loaded LNLCs accumulation near the nucleus of human hepatocellular carcinoma cells, with a large number of cells appearing to be in apoptosis. DOX-loaded LNLCs have also shown higher citotoxicity in cancer cell lines (MDA-MB 231 and HepG2 cell lines after 24 h and in NCI-H1299 cell line after 48 h) when compared to free drug. After 24 h, free DOX was found to have higher cytotoxicity than DOX-loaded LNLCs and empty LNLCs in the normal cell line. Overall, the results demonstrate that DOX-loaded LNLCs have the potential to be explored in cancer therapy.

Paclitaxel-loaded cubosome lipid nanocarriers stabilised with pH and hydrogen peroxide-responsive steric stabilisers as drug delivery vehicles

Responsive nanoparticle delivery systems hold great potential for next-generation chemotherapeutic treatment with reduced off-target side effects. In this work, we formulated responsive lipid-based cubosomes loaded with paclitaxel (PTX) as a model drug and stabilised by novel amphiphilic block copolymers (ABCs) containing the pH-responsive poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA) and/or the hydrogen peroxide (H₂O₂)-responsive poly(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzyl acrylate) (PTBA) blocks. The results showed that these cubosomes with a particle size of around 250 nm exhibited excellent PTX encapsulation efficiency of up to 60% and had the ability to control the release rate of the drug in response to pH and H₂O₂ changes. Specifically, compared to the physiological pH of 7.4, PTX was released faster from the cubosome carriers when exposed to pH 5.5 and/or 50 mM H₂O₂ conditions, which are pathological conditions found in a tumour microenvironment. In vitro cytotoxicity and cell uptake studies further investigated the cellular interactions of these cubosomes. It was found that cubosomes containing PTX had more toxic effects than the control free PTX sample. Compared to cubosomes stabilised by the non-responsive block copolymer Pluronic® F127, the ABC-stabilised cubosomes also had higher cell internalisation efficiency demonstrated by the cytoplasmic fluorescence intensities using confocal microscopy. These results demonstrated that ABCs containing responsive moieties can stabilise lipid cubosomes and enhance controlled release of poorly soluble chemotherapeutics and cellular uptake.

Experimental design, formulation, and in-vivo evaluation of novel anticoagulant Rivaroxaban loaded cubosomes in rats model

The aim of this study was to develop novel cubosomes as an oral delivery system to improve the permeation and anti-clotting activity of Rivaroxaban (RX). The experimental design (2³ full factorial design) was employed to study individual and combined impacts of the assigned formulation variables. The variables RX amount (X₁), Poloxamer (PX): GMO (GMO) ratio (X₂) and PX/GMO: water ratio (X₃) were taken as independent factors, and their effect was examined on entrapment efficiency (Y₁), particle size (Y₂), and zeta potential. (Y₃). The cubosomal vesicle RX-C 3 composed of RX (20 mg), PX: GMO (1:0.5 % w/w), and PX/GMO: water (1:5% w/w) is the optimised formula achieving the required prerequisites. RX-C 3 had shown a vesicle size of 91.2 ± 1.3 nm, entrapment efficiency of 96.27 ± 0.12 %, and zeta potential of -24.1 ± 0.2 mV. The in-vivo studies showed revealed good inhibition of blood clotting, where RX-C 3 significantly increased clotting time by 35% and prothrombin time by 29% compared to Rivarospire^®. In conclusion, the present study suggested that oral cubosomes formulations provide prolonged delivery of Rivaroxaban.

Light-Responsive Molecular Release from Cubosomes Using Swell-Squeeze Lattice Control

Stimuli-responsive materials are crucial to advance controlled delivery systems for drugs and catalysts. Lyotropic liquid crystals (LLCs) have well-defined internal structures suitable to entrap small molecules and can be broken up into low-viscosity dispersions, aiding their application as delivery systems. In this work, we demonstrate the first example of light-responsive cubic LLC dispersions, or cubosomes, using photoswitchable amphiphiles to enable external control over the LLC structure and subsequent on-demand release of entrapped guest molecules. Azobenzene photosurfactants (AzoPS), containing a neutral tetraethylene glycol head group and azobenzene-alkyl tail, are combined (from 10-30 wt %) into monoolein-water systems to create LLC phases. Homogenization of the bulk LLC forms dispersions of particles, ∼200 nm in diameter with internal bicontinuous primitive cubic phases, as seen using small-angle X-ray scattering and cryo-transmission electron microscopy. Notably, increasing the AzoPS concentration leads to swelling of the cubic lattice, offering a method to tune the internal nanoscale structure. Upon UV irradiation, AzoPS within the cubosomes isomerizes within seconds, which in turn leads to squeezing of the cubic lattice and a decrease in the lattice parameter. This squeeze mechanism was successfully harnessed to enable phototriggerable release of trapped Nile Red guest molecules from the cubosome structure in minutes. The ability to control the internal structure of LLC dispersions using light, and the dramatic effect this has on the retention of entrapped molecules, suggests that these systems may have huge potential for the next-generation of nanodelivery.

Simvastatin Coadministration Modulates the Electrostatically Driven Incorporation of Doxorubicin into Model Lipid and Cell Membranes

Understanding the interactions between drugs and lipid membranes is a prerequisite for finding the optimal way to deliver drugs into cells. Coadministration of statins and anticancer agents has been reported to have a positive effect on anticancer therapy. In this study, we elucidate the mechanism by which simvastatin (SIM) improves the efficiency of biological membrane penetration by the chemotherapeutic agent doxorubicin (DOX) in neutral and slightly acidic solutions. The incorporation of DOX, SIM, or a combination of them (DOX:SIM) into selected single-component lipid membranes, zwitterionic unsaturated 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC), neutral cholesterol, and negatively charged 1,2-dimyristoyl-sn-glycero-3-phospho-l-serine (DMPS) was assessed using the Langmuir method. The penetration of neutral lipid monolayers by the codelivery of SIM and DOX was clearly facilitated at pH 5.5, which resembles the pH conditions of the environment of cancer cells. This effect was ascribed to partial neutralization of the DOX positive charge as the result of intermolecular interactions between DOX and SIM. On the other hand, the penetration of the negatively charged DMPS monolayer was most efficient in the case of the positively charged DOX. The efficiency of the drug delivery to the cell membranes was evaluated under in vitro conditions using a panel of cancer-derived cell lines (A172, T98G, and HeLa). MTS and trypan blue exclusion assays were performed, followed by confocal microscopy and spheroid culture tests. Cells were exposed to either free drugs or drugs encapsulated in lipid carriers termed cubosomes. We demonstrated that the viability of cancer cells exposed to DOX was significantly impaired in the presence of SIM, and this phenomenon was greatly magnified when DOX and SIM were coencapsulated in cubosomes. Overall, our results confirmed the utility of the DOX:SIM combination delivery, which enhances the interactions between neutral components of cell membranes and positively charged chemotherapeutic agents.

Cubosomes: Design, Development, and Tumor-Targeted Drug Delivery Applications

Because of the extraordinary advancements in biomedical nanotechnology over the last few decades, traditional drug delivery systems have been transformed into smart drug delivery systems that respond to stimuli. These well-defined nanoplatforms can boost therapeutic targeting efficacy while reducing the side effects/toxicities of payloads, which are crucial variables for enhancing patient compliance by responding to specific internal or external triggers. Cubosomes are lipid-based nano systems that are analogous to well-known vesicular systems, such as lipo- and niosomes. They could be used as part of a unique drug delivery system that includes hydro-, lipo-, and amphiphilic drug molecules. In this review, we critically analyze the relevant literature on cubosomesregarding theories of cubosomeself-assembly, composition, and manufacturing methods, with an emphasis on tumor-targeted drug delivery applications. Due to the bioadhesive and -compatible nature of cubosome dispersion, this review also focuses on a variety of drug delivery applications, including oral, ophthalmic and transdermal.

Novel Gemcitabine-Re(I) Bisquinolinyl Complex Combinations and Formulations With Liquid Crystalline Nanoparticles for Pancreatic Cancer Photodynamic Therapy

With less than 10% of 5-year survival rate, pancreatic ductal adenocarcinoma (PDAC) is known to be one of the most lethal types of cancer. Current literature supports that gemcitabine is the first-line treatment of PDAC. However, poor cellular penetration of gemcitabine along with the acquired and intrinsic chemoresistance of tumor against it often reduced its efficacy and hence necessitates the administration of high gemcitabine dose during chemotherapy. Photodynamic therapy (PDT), a more selective and minimally invasive treatment, may be used synergistically with gemcitabine to reduce the doses utilized and dose-related side effects. This study reports the synergistic use of Re(I) bisquinolinyl complex, a transition metal complex photosensitizer with gemcitabine against PDAC. Re(I) bisquinolinyl complex was found to act synergistically with gemcitabine against PDAC in vitro at various ratios. With the aim to enhance cellular uptake and therapeutic efficiency, the Re(I) bisquinolinyl complex and gemcitabine were encapsulated into liquid crystalline nanoparticles (LCNPs) system. The formulations were found to produce homogeneous drug-loaded LCNPs (average size: 159-173 nm, zeta potential +1.06 to -10 mV). Around 70% of gemcitabine and 90% of the Re(I) bisquinolinyl complex were found to be entrapped efficiently in the formulated LCNPs. The release rate of gemcitabine or/and the Re(I) bisquinolinyl complex loaded into LCNPs was evaluated in vitro, and the hydrophilic gemcitabine was released at a faster rate than the lipophilic Re(I) complex. LCNPs loaded with gemcitabine and Re(I) bisquinolinyl complex in a 1:1 ratio illustrated the best anti-cancer activity among the LCNP formulations (IC₅₀ of BxPC3: 0.15 μM; IC₅₀ of SW 1990: 0.76 μM) through apoptosis. The current findings suggest the potential use of transition metal-based photosensitizer as an adjunctive agent for gemcitabine-based chemotherapy against PDAC and the importance of nano-formulation in such application.

Cubosomal Lipid Formulation for Combination Cancer Treatment: Delivery of a Chemotherapeutic Agent and Complexed α-Particle Emitter 213Bi

Here, we propose tailored lipid liquid-crystalline carriers (cubosomes), which incorporate an anticancer drug (doxorubicin) and complexed short-lived α-emitter (bismuth-213), as a strategy to obtain more effective action toward the cancer cells. Cubosomes were formulated with doxorubicin (DOX) and an amphiphilic ligand (DOTAGA-OA), which forms stable complexes with ²¹³Bi radionuclide. The behavior of DOX incorporated into the carrier together with the chelating agent was investigated, and the drug liberation profile was determined. The experiments revealed that the presence of the DOTAGA-OA ligand affects the activity of DOX when they are incorporated into the same carrier. This unexpected influence was explained based on the results of release studies, which proved the contribution of electrostatics in molecular interactions between the positively charged DOX and negatively charged DOTAGA-OA in acidic and neutral solutions. A significant decrease in the viability of HeLa cancer cells was achieved using sequential cell exposure: first to the radiolabeled cubosomes containing ²¹³Bi complex and next to DOX-doped cubosomes. Therefore, the sequential procedure for the delivery of both drugs encapsulated in cubosomes is suggested for further biological and in vivo studies.

Coupling Lipid Nanoparticle Structure and Automated Single-Particle Composition Analysis to Design Phospholipase-Responsive Nanocarriers

Lipid nanoparticles (LNPs) are versatile structures with tunable physicochemical properties that are ideally suited as a platform for vaccine delivery and RNA therapeutics. A key barrier to LNP rational design is the inability to relate composition and structure to intracellular processing and function. Here Single Particle Automated Raman Trapping Analysis (SPARTA) is combined with small-angle X-ray and neutron scattering (SAXS/SANS) techniques to link LNP composition with internal structure and morphology and to monitor dynamic LNP-phospholipase D (PLD) interactions. This analysis demonstrates that PLD, a key intracellular trafficking mediator, can access the entire LNP lipid membrane to generate stable, anionic LNPs. PLD activity on vesicles with matched amounts of enzyme substrate is an order of magnitude lower, indicating that the LNP lipid membrane structure can be used to control enzyme interactions. This represents an opportunity to design enzyme-responsive LNP solutions for stimuli-responsive delivery and diseases where PLD is dysregulated.

Lipidic cubic-phase leflunomide nanoparticles (cubosomes) as a potential tool for breast cancer management

Despite the fact of availability of several treatments for breast cancer, most of them fail to attain the desired therapeutic response due to their poor bioavailability, high doses, non-selectivity and as a result systemic toxicity. Here in an attempt made to study the transdermal effect of leflunomide (LEF) against breast cancer. In order to improve the poor physicochemical properties of LEF, it was loaded into cubosomes. Cubosomes were prepared by the emulsification method. Colloidal characteristics of cubosomes including particle size, ζ-potential, entrapment efficiency, in-vitro release profile and ex-vivo permeation were studied. In addition, morphology, stability, cytotoxicity and cell uptake in MDA-MB-231 cell line were carried out for the selected cubosomal formulation. The selected LEF loaded cubosomal formulation showed a small particle size (168 ± 1.08) with narrow size distribution (PI 0.186 ± 0.125) and negative ζ potential (–25.5 ± 0.98). Its Entrapment efficiency (EE%) was 93.2% and showed sustained release profile that extended for 24 h. The selected formulation showed stability when stored at 25 °C for three months in terms of size and EE%. TEM images illustrated the cubic structure of the cubosome. Cell culture results revealed the superiority of LEF cubosomes compared to LEF suspension in their cytotoxic effects with an IC50 close to that of doxorubicin. Furthermore, LEF cell uptake was significantly higher for LEF cubosomes. This may be attributed to the effect of nano-encapsulation on enhancing drug pharmacological effects and uptake indicating the potential usefulness of LEF cubosomes for breast cancer management.

Lyotropic Liquid Crystalline Nanostructures as Drug Delivery Systems and Vaccine Platforms

Lyotropic liquid crystals result from the self-assembly process of amphiphilic molecules, such as lipids, into water, being organized in different mesophases. The non-lamellar formed mesophases, such as bicontinuous cubic (cubosomes) and inverse hexagonal (hexosomes), attract great scientific interest in the field of pharmaceutical nanotechnology. In the present review, an overview of the engineering and characterization of non-lamellar lyotropic liquid crystalline nanosystems (LLCN) is provided, focusing on their advantages as drug delivery nanocarriers and innovative vaccine platforms. It is described that non-lamellar LLCN can be utilized as drug delivery nanosystems, as well as for protein, peptide, and nucleic acid delivery. They exhibit major advantages, including stimuli-responsive properties for the “on demand” drug release delivery and the ability for controlled release by manipulating their internal conformation properties and their administration by different routes. Moreover, non-lamellar LLCN exhibit unique adjuvant properties to activate the immune system, being ideal for the development of novel vaccines. This review outlines the recent advances in lipid-based liquid crystalline technology and highlights the unique features of such systems, with a hopeful scope to contribute to the rational design of future nanosystems.

A vibrational in vitro approach to evaluate the potential of monoolein nanoparticles as isofuranodiene carrier in MDA-MB 231 breast cancer cell line: New insights from Infrared and Raman microspectroscopies

Isofuranodiene (IFD) is a sesquiterpene occurring in several plant species, which proved to have multiple anticancer activities. IFD has a lipophilic nature and, hence, a very low water solubility and a poor bioavailability; moreover, it is not stable, undergoing the "Cope rearrangement" to the less active curzerene. The use of appropriate delivery systems can thus be considered as a valid tool to enhance IFD bioavailability, solubility, stability and at the same time also to improve its intracellular uptake and pharmacological activity. Within this frame, monoolein (GMO) nanoparticles loaded with IFD were prepared and their enhanced anticancer activity, compared to pristine IFD, was assessed. In this study, for the first time, an in vitro Fourier Transform Infrared and Raman Microspectroscopy approaches were exploited to evaluate the effects of IFD, alone and loaded in GMO nanoparticles, on MDA-MB 231 breast cancer cell line. The anti-cancer effects of IFD were evidenced by both the spectroscopic techniques and discriminated from the GMO-induced changes in the culture environment; moreover, a synergistic effect of IFD and GMO administration can be envisaged by the experimental results.

Cubosomes as an emerging platform for drug delivery: a state-of-the-art review

Lipid-based drug delivery nanoparticles, including non-lamellar type, mesophasic nanostructured materials of lyotropic liquid crystals (LLCs), have been a topic of interest for researchers for their applications in encapsulation of drugs...

Potentiating the Cytotoxic Activity of a Novel Simvastatin-Loaded Cubosome against Breast Cancer Cells: Insights on Dual Cell Death via Ferroptosis and Apoptosis

Purpose

Female breast cancer is the most prevalent cancer worldwide. Emerging evidence shows that simvastatin (SIM) has promising anticancer activities. However, the underlying mechanisms are not fully elucidated. Increasing reports imply statins can modulate ferroptosis through disrupting reactive oxygen species (ROS) and glutathione peroxidase enzyme (GPX4) levels. However, whether ferroptosis contributes to SIM anticancer activity, especially regarding GPX4 is unclear. Moreover, poor aqueous SIM solubility hinders its delivery in adequate levels to tumor sites. Meanwhile, cubosomes are biocompatible nanocarriers that enhance lipophilic drug delivery. Therefore, in this study, we formulated a novel SIM-loaded cubosome (SIM-CB) and analyzed its cytotoxic activity on MCF-7 cancer cells in comparison with free SIM.

Methods

The present study tested the cytotoxic activity of SIM-CB on MCF-7 cells, in comparison with SIM using sulphorhodamine assay. We analyzed SIM-CB effect on apoptosis and cell cycle using flowcytometry, and investigated its effect on Bcl-2, caspase 3, ROS, reduced glutathione (GSH), lipid peroxides and GPX4 enzyme. Finally, we tested the persistence of SIM-CB apoptosis and ferroptosis activities on MCF-7 cells in presence of vitamin E, a potent antioxidant and ferroptosis inhibitor.

Results

SIM-CB was successfully formulated at the nano size. SIM-CB significantly increased simvastatin therapeutic activity, with IC₅₀ of SIM-CB 52% lower than SIM. 95% CI [1.8, 2.7], SD = 0.34 for SIM-CB, and [4.1, 5.2], SD = 0.45 for SIM. Compared with free SIM, SIM-CB doubled total deaths and increased apoptosis (p < 0.05). Moreover, SIM-CB remarkably increased caspase-3, ROS, and lipid peroxide levels but decreased antiapoptotic Bcl-2 protein, GSH, and GPX4 compared with free SIM. Notably, SIM-CB elicited a high distinguished resistance against the inhibitory effects of vitamin E.

Conclusion

To the best of our knowledge, this study is the first to present SIM-CB as a promising means to enhancing the therapeutic potential of simvastatin against breast cancer cells, through potentiating both apoptosis and ferroptosis.

Balanced lipase interactions for degradation-controlled paclitaxel release from lipid cubic phase formulations

Lipid cubic phase (LCP) formulations enhance the intestinal solubility and bioavailability of hydrophobic drugs by reducing precipitation and facilitating their mass transport to the intestinal surface for absorption. LCPs with an ester linkage connecting the acyl chain to the glycerol backbone (monoacylglycerols), are susceptible to chemical digestion by several lipolytic enzymes including lipases, accelerating the release of hydrophobic agents from the lipid bilayers of the matrix. Unlike regular enzymes that transform soluble substrates, lipolytic enzymes act at the interface of water and insoluble lipid. Therefore, compounds that bind to this interface can enhance or inhibit the activity of enzymes to varying extent. Here, we explore how the lipolysis rate can be tuned by the interfacial interaction of porcine pancreatic lipase with monoolein LCPs containing a known lipase inhibitor, tetrahydrolipstatin. Release of the Biopharmaceutical Classification System (BCS) class IV drug, paclitaxel, from the inhibitor-modified LCP was examined in the presence of lipase and its effectors colipase and calcium. By combining experimental dynamic digestion studies, thermodynamic measurements and molecular dynamics simulations of the competitive inhibition of lipase by tetrahydrolipstatin, we reveal the role and mode of action of lipase effectors in creating a precisely-balanced degradation-controlled LCP release system for the poorly soluble paclitaxel drug.

Cubosomal lipid formulation of nitroalkene fatty acids: Preparation, stability and biological effects

Lipid nitroalkenes – nitro-fatty acids (NO₂–FAs) are formed in vivo via the interaction of reactive nitrogen species with unsaturated fatty acids. The resulting electrophilic NO₂–FAs play an important role in redox homeostasis and cellular stress response. This study investigated the physicochemical properties and reactivity of two NO₂–FAs: 9/10-nitrooleic acid (1) and its newly prepared 1-monoacyl ester, (E)-2,3-hydroxypropyl 9/10-nitrooctadec-9-enoate (2), both synthesized by a direct radical nitration approach. Compounds 1 and 2 were investigated in an aqueous medium and after incorporation into lipid nanoparticles prepared from 1-monoolein, cubosomes 1@CUB and 2@CUB. Using an electrochemical analysis and LC-MS, free 1 and 2 were found to be unstable under acidic conditions, and their degradation occurred in an aqueous environment within a few minutes or hours. This degradation was associated with the production of the NO radical, as confirmed by fluorescence assay. In contrast, preparations 1@CUB and 2@CUB exhibited a significant increase in the stability of the loaded 1 and 2 up to several days to weeks. In addition to experimental data, density functional theory-based calculation results on the electronic structure and structural variability (open and closed configuration) of 1 and 2 were obtained. Finally, experiments with a human HaCaT keratinocyte cell line demonstrated the ability of 1@CUB and 2@CUB to penetrate through the cytoplasmic membrane and modulate cellular pathways, which was exemplified by the Keap1 protein level monitoring. Free 1 and 2 and the cubosomes prepared from them showed cytotoxic effect on HaCaT cells with IC₅₀ values ranging from 1 to 8 μM after 24 h. The further development of cubosomal preparations with embedded electrophilic NO₂–FAs may not only contribute to the field of fundamental research, but also to their application using an optimized lipid delivery vehicle.

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Nitro-fatty acids (NO₂–FAs) are bioactive electrophiles and new drug candidates.

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The study focused on endogenous NO₂-oleic acid and its glycerol ester.

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Cubosomes are lipid nanoparticles stabilizing the incorporated NO₂–FAs.

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Applicability of NO₂-FA-loaded cubosomes was tested on human HaCaT keratinocytes.

Reduction of enzymatic degradation of insulin via encapsulation in a lipidic bicontinuous cubic phase

Oral delivery of the protein drug insulin is not currently possible due to rapid degradation of the secondary structure in low pH conditions in the stomach and under the influence of digestive enzymes in the gastrointestinal tract. Effective oral delivery of insulin and other protein- or peptide-based drugs will, therefore, require encapsulation in a material or nanoparticle. Herein we investigate the ability of the lipid bicontinuous cubic phase formed by two lipids, monoolein (MO) and phytantriol (PT), to protect encapsulated insulin from degradation by the enzyme chymotrypsin, typically found in the small intestine. High encapsulation efficiency (>80%) was achieved in both lipid cubic phases with retention of the underlying cubic nanostructure. Release of insulin from the cubic matrix was shown to be diffusion-controlled; the release rate was dependent on the cubic nanostructure and consistent with measured diffusion coefficients for encapsulated insulin. Encapsulation was shown to significantly retard enzymatic degradation relative to that in water, with the protective effect lasting up to 2 h, exemplifying the potential of these materials to protect the encapsulated protein payload during oral delivery.

Comprehensive and comparative studies on nanocytotoxicity of glyceryl monooleate- and phytantriol-based lipid liquid crystalline nanoparticles

Background

Lipid liquid crystalline nanoparticles (LLCNPs) emerge as a suitable system for drug and contrast agent delivery. In this regard due to their unique properties, they offer a solubility of a variety of active pharmaceutics with different polarities increasing their stability and the possibility of controlled delivery. Nevertheless, the most crucial aspect underlying the application of LLCNPs for drug or contrast agent delivery is the unequivocal assessment of their biocompatibility, including cytotoxicity, genotoxicity, and related aspects. Although studies regarding the cytotoxicity of LLCNPs prepared from various lipids and surfactants were conducted, the actual mechanism and its impact on the cells (both cancer and normal) are not entirely comprehended. Therefore, in this study, LLCNPs colloidal formulations were prepared from two most popular structure-forming lipids, i.e., glyceryl monooleate (GMO) and phytantriol (PHT) with different lipid content of 2 and 20 w/w%, and the surfactant Pluronic F-127 using the top-down approach for further comparison of their properties. Prepared formulations were subjected to physicochemical characterization and followed with in-depth biological characterization, which included cyto- and genotoxicity towards cervical cancer cells (HeLa) and human fibroblast cells (MSU 1.1), the evaluation of cytoskeleton integrity, intracellular reactive oxygen species (ROS) generation upon treatment with prepared LLCNPs and finally the identification of internalization pathways.

Results

Results denote the higher cytotoxicity of PHT-based nanoparticles on both cell lines on monolayers as well as cellular spheroids, what is in accordance with evaluation of ROS activity level and cytoskeleton integrity. Detected level of ROS in cells upon the treatment with LLCNPs indicates their insignificant contribution to the cellular redox balance for most concentrations, however distinct for GMO- and PHT-based LLCNPs. The disintegration of cytoskeleton after administration of LLCNPs implies the relation between LLCNPs and F-actin filaments. Additionally, the expression of four genes involved in DNA damage and important metabolic processes was analyzed, indicating concentration–dependent differences between PHT- and GMO-based LLCNPs.

Conclusions

Overall, GMO-based LLCNPs emerge as potentially more viable candidates for drug delivery systems as their impact on cells is not as deleterious as PHT-based as well as they were efficiently internalized by cell monolayers and 3D spheroids.

Graphic Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s12951-021-00913-5.

Anticancer Activity of Thymoquinone Cubic Phase Nanoparticles Against Human Breast Cancer: Formulation, Cytotoxicity and Subcellular Localization

INTRODUCTION

Triple negative breast cancer is an aggressive disorder which accounts for at least 15% of breast cancer diagnosis and a high percentage of breast cancer morbidity, hence intensive research efforts are focused on the development of effective therapies to overcome the disease. Thymoquinone (TQ), the bioactive constituent of Nigella sativa, exhibits anticancer activity, yet its translation to the clinic is hindered by its poor bioavailability and lack of quantification method in blood and tissues. To overcome these limitations, cubosomes were utilized for the encapsulation and delivery of this anticancer molecule.

METHODS

Thymoquinone loaded cubosomes were prepared through the emulsification homogenization method. The physicochemical characteristics, including particle size, zeta potential, morphology and entrapment efficiency, were studied. Moreover, the in vitro antitumor activity was tested on breast cancer cell lines (MCF-7 and MDA-MB-231) and compared to non-tumorigenic cell line (MCF-10A). Subcellular localization, cellular uptake and apoptotic effects of the formulations were assessed.

RESULTS

The results revealed that the TQ loaded cubosomal formulation exhibited a mean particle size of 98.0 ± 4.10 nm with narrow unimodal distribution. The high entrapment efficiency (96.60 ± 3.58%) and zeta potential (31.50 ±4.20 mV) conceived the effectiveness of this nanosystem for TQ encapsulation. Cell viability in both breast cancer cell lines demonstrated a dose-dependent decrease in response to treatment with free TQ or TQ-loaded cubosomes, with enhanced antitumor activity upon treating with the latter formulation. A significant increase in apoptotic bodies and cleaved caspase 3 was observed upon treatment of MDA-MB-231 cells with either TQ or TQ-loaded cubosomes. Localization and trafficking studies unveiled that cubosomes accumulate in the cytoplasm of the studied breast cancer cell lines.

DISCUSSION

Our results show that thymoquinone encapsulation in cubosomal nanoparticles provides a promising anticancer drug delivery system with the ability to label, detect and subsequently trace it within the human cells.

Lipidic Cubic-Phase Nanoparticles (Cubosomes) Loaded with Doxorubicin and Labeled with 177Lu as a Potential Tool for Combined Chemo and Internal Radiotherapy for Cancers

Lipid liquid-crystalline nanoparticles (cubosomes) were used for the first time as a dual-modality drug delivery system for internal radiotherapy combined with chemotherapy. Monoolein (GMO)-based cubosomes were prepared by loading the anticancer drug, doxorubicin and a commonly used radionuclide, low-energy beta (β⁻)-emitter, ¹⁷⁷Lu. The radionuclide was complexed with a long chain derivative of DOTAGA (DOTAGA-OA). The DOTAGA headgroup of the chelator was exposed to the aqueous channels of the cubosomes, while, concerning OA, the hydrophobic tail was embedded in the nonpolar region of the lipid bilayer matrix, placing the radioactive dopant in a stable manner inside the cubosome. The cubosomes containing doxorubicin and the radionuclide complex increased the cytotoxicity measured by the viability of the treated HeLa cells compared with the effect of single-drug cubosomes containing either the DOX DOTAGA-OA or DOTAGA-OA-¹⁷⁷Lu complex. Multifunctional lipidic nanoparticles encapsulating the chemotherapeutic agent together with appropriately complexed (β⁻) radionuclide are proposed as a potential strategy for effective local therapy of various cancers.

Phytantriol-Based Cubosome Formulation as an Antimicrobial against Lipopolysaccharide-Deficient Gram-Negative Bacteria

Treatment of multidrug-resistant (MDR) bacterial infections increasingly relies on last-line antibiotics, such as polymyxins, with the urgent need for discovery of new antimicrobials. Nanotechnology-based antimicrobials have gained significant importance to prevent the catastrophic emergence of MDR over the past decade. In this study, phytantriol-based nanoparticles, named cubosomes, were prepared and examined in vitro by minimum inhibitory concentration (MIC) and time-kill assays against Gram-negative bacteria: Acinetobacter baumannii, Klebsiella pneumoniae, and Pseudomonas aeruginosa. Phytantriol-based cubosomes were highly bactericidal against polymyxin-resistant, lipopolysaccharide (LPS)-deficient A. baumannii strains. Small-angle neutron scattering (SANS) was employed to understand the structural changes in biomimetic membranes that replicate the composition of these LPS-deficient strains upon treatment with cubosomes. Additionally, to further understand the membrane-cubosome interface, neutron reflectivity (NR) was used to investigate the interaction of cubosomes with model bacterial membranes on a solid support. These results reveal that cubosomes might be a new strategy for combating LPS-deficient Gram-negative pathogens.

Nano liposomal and cubosomal formulations with platinum-based anticancer agents: therapeutic advances and challenges

Nephrotoxicity, neurotoxicity and multidrug resistance in tumor cells can result from platinum-based anticancer (PBA) agents which can be reduced by nano formulations. Recently, novel formulations based on liposomes and cubosomes have been described as efficient strategies to overcome nephrotoxicity, ototoxicity, neurotoxicity, cardiotoxicity, hematological toxicities, hepatotoxicity and gastrointestinal toxicity as well as multidrug resistance. The co-delivery of anticancer agents concomitant with PBAs via biocompatible and biodegradable smart liposomes and cubosomes can augment therapeutic results of chemotherapy as well as radiotherapy owing to their high accessibility of surface and internal modification. For this purpose, surface, bilayer or core sections of these formulations can be functionalized by pure PBAs or modified PBAs. In this review, recent significant advances and challenges related to various liposomal and cubosomal formulations of PBA are presented in order to emphasize suitable formulations for anticancer applications with critical thoughts provided on how the field can progress.

Combinatory Treatment with miR-7-5p and Drug-Loaded Cubosomes Effectively Impairs Cancer Cells

BACKGROUND

Multidrug resistance (MDR) is an emerging problem in the treatment of cancer. Therefore, there is a necessity for novel strategies that would sensitize tumor cells to the administered chemotherapeutics. One of the innovative approaches in fighting drug-resistant tumors is the treatment of cancer with microRNA (miRNA), or the use of cubosomes (lipid nanoparticles) loaded with drugs. Here, we present a study on a novel approach, which combines both tools.

METHODS

Cubosomes loaded with miR-7-5p and chemotherapeutics were developed. The effects of drug- and miRNA-loaded vehicles on glioma- (A172, T98G), papillary thyroid- (TPC-1) and cervical carcinoma-derived (HeLa) cells were analyzed using molecular biology techniques, including quantitative real-time PCR, MTS-based cell proliferation test, flow cytometry and spheroids formation assay.

RESULTS

The obtained data indicate that miR-7-5p increases the sensitivity of the tested cells to the drug, and that nanoparticles loaded with both miRNA and the drug produce a greater anti-tumor effect in comparison to the free drug treatment. It was found that an increased level of apoptosis in the drug/miRNA co-treated cells is accompanied by an alternation in the expression of the genes encoding for key MDR proteins of the ABC family.

CONCLUSIONS

Overall, co-administration of miR-7-5p with a chemotherapeutic can be considered a promising strategy, leading to reduced MDR and the induction of apoptosis in cancer cells.

Multifunctional cubic liquid crystalline nanoparticles for chemo- and photodynamic synergistic cancer therapy

With the aim of engineering multifunctional nanoparticles useful for cancer therapy, a diketopyrrolopyrrole-porphyrin based photosensitizer was here conjugated to a block copolymer (Pluronic F108), and used to stabilize in water lipidic cubic liquid crystalline nanoparticles (cubosomes), also loaded with the antineoplastic agent docetaxel. The physicochemical characterization by SAXS, DLS, and cryo-TEM demonstrated that the formulation consisted of cubosomes, about 150 nm in size, possessing a bicontinuous cubic structure (space group Pn3m). The cellular imaging experiments proved that these nanoparticles localized in lysosomes and mitochondria, while cytotoxicity tests evidenced a slight but significant synergistic effect which, after irradiation, increased the toxicity induced by docetaxel alone, allowing further reduction of cell viability.

Theranostic combinatorial drug-loaded coated cubosomes for enhanced targeting and efficacy against cancer cells

Cubosomes, a product of nanobioengineering, are self-structured lipid nanoparticles that act like drug-loaded theranostic probes. Here, we describe a simple method for the preparation of combinatorial drug-loaded cubosomes with, proof-of-principle, therapeutic effect against cancer cells, along with diagnostic capabilities. Anticancer drugs cisplatin and paclitaxel were loaded in the cubosomes in combination. The cubosomes were coated with a layer of poly-Ɛ-lysine, which helped avoid the initial burst release of drug and allowed for a slow and sustained release for better efficacy. Cubosomes were imaged by transmission electron microscope, and their dispersion analyzed in vitro by differential scanning calorimetric and X-ray diffractogram studies. The microscopic images depicted spherical polyangular structures, which are easily distinguishable. The analyses revealed that the drug is uniformly dispersed all through the cubosomes. Further characterization was carried out by zeta-potential measurement, in vitro release, and entrapment efficiency studies. The in vitro studies established that the coating of cubosomes successfully reduced the burst release of drugs initially and confirmed a slow, sustained release over increased time. Comparative cytotoxicity of coated, uncoated, and blank cubosomes was evaluated, using human hepatoma HepG2 cell line, and the formulations were found to be entirely nontoxic, similar to the blank ones. The therapeutic efficiency of the cubosomes against HeLa cells was confirmed by the impedance measurement and fluorescent imaging. Furthermore, the reduction in impedance in cells treated with coated combinatorial cubosomes proved the impairment of HeLa cells, as confirmed by fluorescence microscopy.