Strategies for optimizing polymer-lipid hybrid nanoparticle-mediated drug delivery

An update on strategies for optimizing polymer-lipid hybrid nanoparticle-mediated drug delivery: exploiting transformability and bioactivity of PLN and harnessing intracellular lipid transport mechanism

INTRODUCTION

Polymer-lipid hybrid nanoparticle (PLN) is an emerging nanoplatform with distinct properties and functionalities from other nanocarrier systems. PLN can be optimized to overcome various levels of drug delivery barriers to achieve desired therapeutic outcomes via rational selection of polymer and lipid combinations based on a thorough understanding of their properties and interactions with therapeutic agents and biological systems.

AREAS COVERED

This review provides an overview of PLN including the motive and history of PLN development, types of PLN, preparation methods, attestations of their versatility, and design strategies to circumvent various barriers for increasing drug delivery accuracy and efficiency. It also highlights recent advances in PLN design including: rationale selection of polymer and lipid components to achieve spatiotemporal drug targeting and multi-targeted cascade drug delivery; utilizing the intracellular lipid transport mechanism for active targeting to desired organelles; and harnessing bioreactive lipids and polymers to magnify therapeutic effects.

EXPERT OPINION

A thorough understanding of properties of PLN components and their biofate is important for enhancing disease site targeting, deep tumor tissue penetration, cellular uptake, and intracellular trafficking of PLN. For futuristic PLN development, active lipid transport and dual functions of lipids and polymers as both nanocarrier material and pharmacological agents can be further explored.

Sonophoresis-assisted transdermal delivery of antimigraine-loaded nanolipomers: Radio-tracking, histopathological assessment and in-vivo biodistribution study

Migraine is a disabling neurovascular polygenic disorder affecting life quality with escorted socioeconomic encumbrances. Herein, we investigated the consolidated amalgamation of passive lipomer approach alongside active sonophoresis assisted transdermal delivery of zolmitriptan (ZT) using high frequency ultrasound pre-treatment protocol to mitigate migraine attacks. A modified nanoprecipitation technique was utilized to prepare zolmitriptan loaded lipomers (ZTL) adopting 23 factorial design. Three factors were scrutinized namely lipid type, ZT: lipid ratio and ZT: Gantrez® ratio. The prepared systems were characterized regarding particle size, zeta potential, polydispersity index, entrapment efficiency and in-vitro release studies. The best achieved ZTL system was evaluated for ZT- Gantrez® intermolecular interactions, drug crystallinity, morphology, ex-vivo permeation and histopathological examination. Finally, a comparative in-vivo biodistribution study through radiotracking technique using Technetium-99 m was adopted. L2 was the best-achieved ZTL system with respect to spherical particle size (390.7 nm), zeta-potential (-30.8 mV), PDI (0.2), entrapment efficiency (86.2%), controlled release profile, flux (147.13 μg/cm2/hr) and enhancement ratio (5.67). Histopathological studies proved the safety of L2 system upon application on skin. L2 revealed higher brain Cmax (12.21 %ID/g), prolonged brain MRT (8.67 hr), prolonged brain 0.23 hr), significantly high relative bioavailability (2929.36%) and similar brain Tmax (0.5 hr) compared to I.V. route with higher brain/blood ratio. Thus, sonophoresis assisted transdermal delivery of ZTL offers a propitious alterative to alleviate migraine symptoms.

Lipid-based nanoparticles as drug delivery systems for cancer immunotherapy

Immune checkpoint inhibitors (ICIs) have shown remarkable success in cancer treatment. However, in cancer patients without sufficient antitumor immunity, numerous data indicate that blocking the negative signals elicited by immune checkpoints is ineffective. Drugs that stimulate immune activation-related pathways are emerging as another route for improving immunotherapy. In addition, the development of nanotechnology presents a promising platform for tissue and cell type-specific delivery and improved uptake of immunomodulatory agents, ultimately leading to enhanced cancer immunotherapy and reduced side effects. In this review, we summarize and discuss the latest developments in nanoparticles (NPs) for cancer immuno-oncology therapy with a focus on lipid-based NPs (lipid-NPs), including the characteristics and advantages of various types. Using the agonists targeting stimulation of the interferon genes (STING) transmembrane protein as an exemplar, we review the potential of various lipid-NPs to augment STING agonist therapy. Furthermore, we present recent findings and underlying mechanisms on how STING pathway activation fosters antitumor immunity and regulates the tumor microenvironment and provide a summary of the distinct STING agonists in preclinical studies and clinical trials. Ultimately, we conduct a critical assessment of the obstacles and future directions in the utilization of lipid-NPs to enhance cancer immunotherapy.

Hydrocortisone-Loaded Lipid-Polymer Hybrid Nanoparticles for Controlled Topical Delivery: Formulation Design Optimization and In Vitro and In Vivo Appraisal

The barrier functionalities of the skin offer a major but not insuperable hindrance for fabrication of skin delivery effective systems. This work aimed to develop an optimized lipid polymer hybrid nanoparticle and assess the skin delivery effectiveness of hydrocortisone (9.872 ± 0.361 × 10^-3 cm²/h) of a drug through the skin from an optimized formulation when compared with a drug solution. Meanwhile, histological examination after topical application of the optimized formulation showed a safe increase in epidermal thickness. In vivo, the optimized formulation showed promising anti-inflammatory activity in a croton oil-induced ear rosacea model. As an excellent anti-inflammatory agent, these findings propose that the use of lipomers could be a promising strategy to improve the topical effectiveness of hydrocortisone acetate (HCA) against inflammatory diseases. Collectively, these results support our view that lipid polymer hybrid nanoparticles can proficiently deliver hydrocortisone to the skin in treating skin inflammatory conditions.

Development and in-vitro evaluation of chitosan and glyceryl monostearate based matrix lipid polymer hybrid nanoparticles (LPHNPs) for oral delivery of itraconazole

Itraconazole (ICZ) is a broad spectrum antifungal drug, but used as second or third line therapy due to its low and erratic oral bioavailability. This work was carried out to prepare and characterize matrix type lipid-polymer hybrid nanoparticles (LPHNPs) for dissolution enhancement of ICZ. LPHNPs were prepared using solvent diffusion/emulsification technique. Matrix LPHNPs were composed of chitosan (polymer), glyceryl monostearate (lipid) and poloxamer 188 (stabilizer). LPHNPs loaded with ICZ (LPHNPs-1, LPHNPs-2, LPHNPs-3 and LPHNPs-4) were developed using varying concentration of chitosan whereas LPHNPs (LPHNPs-5, LPHNPs-6, LPHNPs-7 and LPHNPs-8) were prepared using varying concentrations of poloxamer 188. LPHNPs loaded with ICZ were further evaluated for entrapment efficiency, particle size, polydispersity index (PDI), zeta potential and dissolution profiles at biorelevant pH conditions. The particle size (LPHNPs-1 to LPHNPs-4) was found to be in range of 421-588 nm with PDI values 0.34-0.41. The particles size of LPHNPs-5 to LPHNPs-8 was found to be in range of 489-725 nm with PDI 0.34-0.74. The entrapment efficiency of LPHNPs-1 to LPHNPs-4 was found to be in range of 85.21%-91.34%. The entrapment efficiency of LPHNPs-5 to LPHNPs-8 was found to be in range 78.32%-90.44%. . The scanning electron microscopy of optimized formulations LPHNPs-1 and LPHNPs-5 indicated formation of oval shaped nanoparticles. DSC thermogram of ICZ loaded LPHNPs also depicted the conversion of crystalline form of ICZ into amorphous form demonstrating the internalization and dissolution enhancement of drug in the hybrid matrix. The cumulative drug dissolved at acidic pH 1.2 was found to be 23.3% and 19.8% for LPHNPs-1 and LPHNPs-5 respectively. Similarly at basic pH values 7.4, cumulative amount of drug dissolved was 90.2% and 83.4% for LPHNPs-1 and LPHNPs-5 respectively. Drug dissolution kinetics exhibited fickian diffusion best described by Korse-meyer Peppas model. The results suggested that chitosan and glyceryl monostearate based matrix LPHNPs could be used as promising approach for dissolution enhancement of ICZ which could further increase its bioavailability.

Encapsulation of Vitamins Using Nanoliposome: Recent Advances and Perspectives

Nowadays the importance of vitamins is clear for everyone. However, many patients are suffering from insufficient intake of vitamins. Incomplete intake of different vitamins from food sources due to their destruction during food processing or decrease in their bioavailability when mixing with other food materials, are factors resulting in vitamin deficiency in the body. Therefore, various lipid based nanocarriers such as nanoliposomes were developed to increase the bioavailability of bioactive compounds. Since the function of nanoliposomes containing vitamins on the body has a direct relationship with the quality of produced nanoliposomes, this review study was planned to investigate the several aspects of liposomal characteristics such as size, polydispersity index, zeta potential, and encapsulation efficiency on the quality of synthesized vitamin-loaded nanoliposomes.

Assembly methods for asymmetric lipid and polymer-lipid vesicles

Asymmetric unilamellar vesicles are aqueous bodies surrounded by two dissimilar leaflets made from lipids, polymers, or both. They are great models for cell membranes and attractive vehicles in potential biomedicine applications. Despite their promise, asymmetric unilamellar vesicles are not widely studied or adopted in applications. This is largely due to the complexity in generating asymmetric membranes. Recent technical advances in microfluidics have opened doors to high throughput fabrication of asymmetric unilamellar vesicles. In this review, we focus on microfluidic methods for generating asymmetric lipid vesicles, with two dissimilar lipid leaflets, and asymmetric lipid-polymer vesicles, with one lipid leaflet and one polymer leaflet. We also review a few standard non-microfluidic methods for generating asymmetric vesicles. We hope to highlight the improved capability in obtaining asymmetric vesicles through a variety of methods and encourage the wider scientific community to adopt some of these for their own work.

Lipid-Polymer Hybrid Nanocarriers for Oral Delivery of Felodipine: Formulation, Characterization and Ex Vivo Evaluation

Purpose: Felodipine, is a calcium-channel antagonist used for hypertension and angina pectoris. It is practically insoluble in aqueous media and shows low oral bioavailability (15%-20%). This investigation aims to prepare and characterize oral felodipine lipid-polymer hybrid nanocarriers (LPHNs) to increase solubility and control delivery for increasing bioavailability and enhance patient compliance. Methods: The newly microwave-based method was prepared with felodipine LPHNs (H1-H35) successfully. The (H1-H35) were subjected to thermodynamic stability experiments. After that, select nine felodipine LPHNs (F1-F9) that have smart physical stability for further optimization of different characterization processes. Results: The felodipine LPHNs (F4) are considered the most optimized formula. It was characterized by lower particle size (33.3 nm), lower PDI (0.314), high zeta potential (13.6 mV), entrapment efficiency is (81.645% w/w), drug loading is (16.329% w/w), the pH value is 4, excellent percent of light transmittance (95.5%), pseudoplastic rheogram, significantly high (P < 0.05) dissolution rate with sustained drug delivery and success ex-vivo intestinal permeation attributes. The (F4) subject for further investigations of Fourier transformed infrared spectroscopy (FTIR), atomic force microscopy (AFM), and transmission electron microscopy (TEM). The results of FTIR, AFM, and TEM indicate there is no interaction between the felodipine and excipients and that the particulate system in the nanoscale dispersion system confirms the high stability. Conclusion: The optimized felodipine LPHNs (F1-F9) formulations were smart formulations for sustained oral delivery of felodipine and that F4 was the most optimized formula according to its characterization processes.

Advances in Nanomedicine Design: Multidisciplinary Strategies for Unmet Medical Needs

Globally, a rising burden of complex diseases takes a heavy toll on human lives and poses substantial clinical and economic challenges. This review covers nanomedicine and nanotechnology-enabled advanced drug delivery systems (DDS) designed to address various unmet medical needs. Key nanomedicine and DDSs, currently employed in the clinic to tackle some of these diseases, are discussed focusing on their versatility in diagnostics, anticancer therapy, and diabetes management. First-hand experiences from our own laboratory and the work of others are presented to provide insights into strategies to design and optimize nanomedicine- and nanotechnology-enabled DDS for enhancing therapeutic outcomes. Computational analysis is also briefly reviewed as a technology for rational design of controlled release DDS. Further explorations of DDS have illuminated the interplay of physiological barriers and their impact on DDS. It is demonstrated how such delivery systems can overcome these barriers for enhanced therapeutic efficacy and how new perspectives of next-generation DDS can be applied clinically.

Recent Fabrication Methods to Produce Polymer-Based Drug Delivery Matrices (Experimental and In Silico Approaches)

The study of novel drug delivery systems represents one of the frontiers of the biomedical research area. Multi-disciplinary scientific approaches combining traditional or engineered technologies are used to provide major advances in improving drug bioavailability, rate of release, cell/tissue specificity and therapeutic index. Biodegradable and bio-absorbable polymers are usually the building blocks of these systems, and their copolymers are employed to create delivery components. For example, poly (lactic acid) or poly (glycolic acid) are often used as bricks for the production drug-based delivery systems as polymeric microparticles (MPs) or micron-scale needles. To avoid time-consuming empirical approaches for the optimization of these formulations, in silico-supported models have been developed. These methods can predict and tune the release of different drugs starting from designed combinations. Starting from these considerations, this review has the aim of investigating recent approaches to the production of polymeric carriers and the combination of in silico and experimental methods as promising platforms in the biomedical field.

Hesperidin-Loaded Lipid Polymer Hybrid Nanoparticles for Topical Delivery of Bioactive Drugs

Hesperidin is a bioflavonoid constituent that among many other biological activities shows significant wound healing properties. However, the bioavailability of hesperidin when applied topically is limited due to its low solubility and systemic absorption, so novel dosage forms are needed to improve its therapeutic efficacy. The objectives of this study were to develop hesperidin-loaded lipid-polymer hybrid nanoparticles (HLPHNs) to enhance the delivery of hesperidin to endogenous sites in the wound bed and promote the efficacy of hesperidin. HLPHNs were optimized by response surface methodology (RSM) using the Box-Behnken design. HLPHNs were prepared using an emulsion-solvent evaporation method based on a double emulsion of water-in-oil-in-water (w/o/w) followed by freeze-drying to obtain nanoparticles. The prepared formulations were characterized using various evaluation parameters. In addition, the antioxidant activity of HLPHN 4 was investigated in vitro using the DPPH model. Seventeen different HLPHNs were prepared and the HLPHN4 exhibited the best mean particle size distribution, zeta potential, drug release and entrapment efficiency. The values are 91.43 nm, +23 mV, 79.97% and 92.8%, respectively. Transmission electron microscope showed similar spherical morphology as HLPHN4. Differential scanning calorimetry verified the physical stability of the loaded drug in a hybrid system. In vitro release studies showed uniform release of the drug over 24 h. HLPHN4 showed potent antioxidant activity in vitro in the DPPH model. The results of this study suggest that HLPHNs can achieve sustained release of the drug at the wound site and exhibit potent in vitro antioxidant activity.

Engineered Aptamer-Organic Amphiphile Self-Assemblies for Biomedical Applications: Progress and Challenges

Currently, nucleic acid aptamers are exploited as robust targeting ligands in the biomedical field, due to their specific molecular recognition, little immunogenicity, low cost, ect. Thanks to the facile chemical modification and high hydrophilicity, aptamers can be site-specifically linked with hydrophobic moieties to prepare aptamer-organic amphiphiles (AOAs), which spontaneously assemble into aptamer-organic amphiphile self-assemblies (AOASs). These polyvalent self-assemblies feature with enhanced target-binding ability, increased resistance to nuclease, and efficient cargo-loading, making them powerful platforms for bioapplications, including targeted drug delivery, cell-based cancer therapy, biosensing, and bioimaging. Besides, the morphology of AOASs can be elaborately manipulated for smarter biomedical functions, by regulating the hydrophilicity/hydrophobicity ratio of AOAs. Benefiting from the boom in DNA synthesis technology and nanotechnology, various types of AOASs, including aptamer-polymer amphiphile self-assemblies, aptamer-lipid amphiphile self-assemblies, aptamer-cell self-assemblies, ect, have been constructed with great biomedical potential. Particularly, stimuli-responsive AOASs with transformable structure can realize site-specific drug release, enhanced tumor penetration, and specific target molecule detection. Herein, the general synthesis methods of oligonucleotide-organic amphiphiles are firstly summarized. Then recent progress in different types of AOASs for bioapplications and strategies for morphology control are systematically reviewed. The present challenges and future perspectives of this field are also discussed.

Optimizing the Design of Blood-Brain Barrier-Penetrating Polymer-Lipid-Hybrid Nanoparticles for Delivering Anticancer Drugs to Glioblastoma

PURPOSE

Chemotherapy for glioblastoma multiforme (GBM) remains ineffective due to insufficient penetration of therapeutic agents across the blood-brain barrier (BBB) and into the GBM tumor. Herein, is described, the optimization of the lipid composition and fabrication conditions for a BBB- and tumor penetrating terpolymer-lipid-hybrid nanoparticle (TPLN) for delivering doxorubicin (DOX) to GBM.

METHODS

The composition of TPLNs was first screened using different lipids based on nanoparticle properties and in vitro cytotoxicity by using 2³ full factorial experimental design. The leading DOX loaded TPLNs (DOX-TPLN) were prepared by further optimization of conditions and used to study cellular uptake mechanisms, in vitro cytotoxicity, three-dimensional (3D) glioma spheroid penetration, and in vivo biodistribution in a murine orthotopic GBM model.

RESULTS

Among various lipids studied, ethyl arachidate (EA) was found to provide excellent nanoparticle properties e.g., size, polydispersity index (PDI), zeta potential, encapsulation efficiency, drug loading, and colloidal stability, and highest anticancer efficacy for DOX-TPLN. Further optimized EA-based TPLNs were prepared with an optimal particle size (103.8 ± 33.4 nm) and PDI (0.208 ± 0.02). The resultant DOX-TPLNs showed ~ sevenfold higher efficacy than free DOX against human GBM U87-MG-RED-FLuc cells in vitro. The interaction between the TPLNs and the low-density lipoprotein receptors also facilitated cellular uptake, deep penetration into 3D glioma spheroids, and accumulation into the in vivo brain tumor regions of DOX-TPLNs.

CONCLUSION

This work demonstrated that the TPLN system can be optimized by rational selection of lipid type, lipid content, and preparation conditions to obtain DOX-TPLN with enhanced anticancer efficacy and GBM penetration and accumulation.

Polymeric Lipid Hybrid Nanoparticles (PLNs) as Emerging Drug Delivery Platform-A Comprehensive Review of Their Properties, Preparation Methods, and Therapeutic Applications

Polymeric lipid hybrid nanoparticles (PLNs) are core–shell nanoparticles made up of a polymeric kernel and lipid/lipid–PEG shells that have the physical stability and biocompatibility of both polymeric nanoparticles and liposomes. PLNs have emerged as a highly potent and promising nanocarrier for a variety of biomedical uses, including drug delivery and biomedical imaging, owing to recent developments in nanomedicine. In contrast with other forms of drug delivery systems, PLNs have been regarded as seamless and stable because they are simple to prepare and exhibit excellent stability. Natural, semi-synthetic, and synthetic polymers have been used to make these nanocarriers. Due to their small scale, PLNs can be used in a number of applications, including anticancer therapy, gene delivery, vaccine delivery, and bioimaging. These nanoparticles are also self-assembled in a reproducible and predictable manner using a single or two-step nanoprecipitation process, making them significantly scalable. All of these positive attributes therefore make PLNs an attractive nanocarrier to study. This review delves into the fundamentals and applications of PLNs as well as their formulation parameters, several drug delivery strategies, and recent advancements in clinical trials, giving a comprehensive insight into the pharmacokinetic and biopharmaceutical aspects of these hybrid nanoparticles.

Strategies for Preparing Different Types of Lipid Polymer Hybrid Nanoparticles in Targeted Tumor Therapy

At present, cancer is one of the most common diseases in the world, causing a large number of deaths and seriously affecting people's health. The traditional treatment of cancer is mainly surgery, radiotherapy or chemotherapy. Conventional chemotherapy is still an important treatment, but it has some shortcomings, such as poor cell selectivity, serious side effects, drug resistance and so on. Nanoparticle administration can improve drug stability, reduce toxicity, prolong drug release time, prolong system half-life, and bring broad prospects for tumor therapy. Lipid polymer hybrid nanoparticles (LPNs), which combine the advantages of polymer core and phospholipid shell to form a single platform, have become multi-functional drug delivery platforms. This review introduces the basic characteristics, structure and preparation methods of LPNs, and discusses targeting strategies of LPNs in tumor therapy in order to overcome the defects of traditional drug therapy.

Exploring the transformability of polymer-lipid hybrid nanoparticles and nanomaterial-biology interplay to facilitate tumor penetration, cellular uptake and intracellular targeting of anticancer drugs

BACKGROUND

Successful delivery of anticancer drugs to intracellular targets requires different properties of the nanocarrier to overcome multiple transport barriers. However, few nanocarrier systems, to date, possess such properties, despite knowledge about the biological fate of inorganic and polymeric nanocarriers in relation to their fixed size, shape and surface properties. Herein, a polymer-lipid hybrid nanoparticle (PLN) system is described with size and shape transformability and its mechanisms of cellular uptake and intracellular trafficking are studied.

METHODS

Pharmaceutical lipids were screened for use in transformable PLN. Mechanisms of cellular uptake and the role of fatty acid-binding proteins in intracellular trafficking of PLN were investigated in breast cancer cells. Intra-tumoral penetration and retention of doxorubicin (DOX) were evaluated by confocal microscopy.

RESULTS

The lead PLNs showed time-dependent size reduction and shape change from spherical to spiky shape. This transformability of PLNs and lipid trafficking pathways facilitated intracellular transport of DOX-loaded PLN (DOX-PLN) into mitochondria and nuclei. DOX-PLN significantly increased DOX penetration and retention over free DOX or non-transformable liposomal DOX particles at 4 h post-intravenous administration.

CONCLUSION

Transformability of PLN and lipid-biology interplay can be exploited to design new nanocarriers for effective drug delivery to tumor cells and intracellular targets.

Recent Advances in the Use of Lipid-Based Nanoparticles Against Glioblastoma Multiforme

Glioblastoma (GBM) is the most common and aggressive malignant brain tumor in adults. Although the overall incidence is less than 10 per 100,000 individuals, its poor prognosis and low survival rate make GBM a crucial public health issue. The main challenges for GBM treatment are related to tumor location and its complex and heterogeneous biology. In this sense, a broad range of nanoparticles with different sizes, architectures, and surface properties, have been engineered as brain drug delivery systems. Among them, lipid-based nanoparticles, such as liposomes, have been pointed out as promising materials to deliver antitumoral drugs to the central nervous system and thus, to improve brain drug targeting and therapeutic efficiency. Here, we describe the synthesis and general characteristics of lipid-based nanoparticles, as well as evidence in the past 5 years regarding their potential use to treat GBM.

Lipid-polymer hybrid nanoparticles in cancer therapy: current overview and future directions

Cancer remains one of the leading cause of death worldwide. Current therapies are still ineffective in completely eradicating the disease. In the last two decades, the use of nanodelivery systems has emerged as an effective way to potentiate the therapeutic properties of anti-cancer drugs by improving their solubility and stability, prolong drug half-lives in plasma, minimize drug’s toxicity by reducing its off-target distribution, and promote drugs’ accumulation at the desired target site. Liposomes and polymer nanoparticles are the most studied and have demonstrated to be the most effective delivery systems for anti-cancer drugs. However, both liposomes and polymeric nanoparticles suffer from limitations, including high instability, rapid drug release, limited drug loading capacity, low biocompatibility and lack of suitability for large-scale production. To overcome these limitations, lipid-polymer hybrid nanoparticles (LPHNPs) have been developed to merge the advantages of both lipid- and polymer-based nanocarriers, such as high biocompatibility and stability, improved drug loading and controlled release, as well as increased drug half-lives and therapeutic efficacy. This review provides an overview on the synthesis, properties and application of LPHNPs for cancer therapy.

Conventional Nanosized Drug Delivery Systems for Cancer Applications

Clinical responses and tolerability of conventional nanocarriers (NCs) are sometimes different from those expected in anticancer therapy. Thus, new smart drug delivery systems (DDSs) with stimuli-responsive properties and novel materials have been developed. Several clinical trials demonstrated that these DDSs have better clinical therapeutic efficacy in the treatment of many cancers than free drugs. Composition of DDSs and their surface properties increase the specific targeting of therapeutics versus cancer cells, without affecting healthy tissues, and thus limiting their toxicity versus unspecific tissues. Herein, an extensive revision of literature on NCs used as DDSs for cancer applications has been performed using the available bibliographic databases.

Novel Self-Assembled Polycaprolactone-Lipid Hybrid Nanoparticles Enhance the Antibacterial Activity of Ciprofloxacin

Ciprofloxacin (CIP), a widely used antibiotic, is a poor biopharmaceutical resulting in low bioavailability. We optimized a CIP polymer-lipid hybrid nanoparticle (CIP-PLN) delivery system to enhance its biopharmaceutical attributes and the overall therapeutic performance. CIP-PLN formulations were prepared by a direct emulsification-solvent-evaporation method. Varying the type and ratio of lipid was tried to optimize a CIP-PLN formulation. All the prepared formulations were evaluated for their particle size, polydispersity index, zeta potential, physical stability, and drug entrapment efficiency. The drug in vitro release profile was also studied. Antibacterial activities were tested by the agar diffusion method for all CIP-PLN formulations against an Escherichia coli clinical bacterial isolate (EC04). CIP-PLN formulations showed average sizes in the range of 133.9 ± 1.7 nm to 217.1 ± 0.8 nm, exhibiting high size uniformity as indicated by polydispersity indices lower than 0.25. The entrapment efficiency was close to 80% for all formulations. The differential scanning calorimetry (DSC) thermograms indicated the existence of CIP in the amorphous state in all PLN formulations. Fourier transform infrared spectra indicated deep incorporation of molecular CIP within the polymer matrix. The release profile of CIP from PLN formulas showed a uniform prolonged drug profile, extended for a week from most formulations with a zero-order kinetics. The antibacterial activity of CIP-PLN formulations showed significantly higher antibacterial activity only with F4 containing lecithin as the lipid component. In conclusion, we successfully optimized a CIP-PLN formulation with a low nanoparticle size in a close range, high percentage of entrapment efficiency and drug loading, uniform prolonged release rate, and higher antibacterial activity against the EC04 clinical isolate.

Therapeutic Strategies for Erectile Dysfunction With Emphasis on Recent Approaches in Nanomedicine

This review addressed erectile dysfunction, regarding pathophysiology and therapeutic strategies. The line of treatment includes phosphodiesterase type-5 inhibitors and other types of therapy like topical and stem-cell transplant. Scientific literature was assessed to investigate the impact of nanotechnology on erectile dysfunction therapy. Various nanotechnology approaches were applied, like vesicular systems, lipid-based carriers, nanocrystals, dendrimers, liquid crystalline systems and nanoemulsions. Smart nano-systems can alter the landscape of the modern pharmaceutical industry by re- investigation of pharmaceutically suboptimal but biologically active entities for treatment of erectile dysfunction which were previously considered undeveloped.

Delivering Combination Chemotherapies and Targeting Oncogenic Pathways via Polymeric Drug Delivery Systems

The side-effects associated with chemotherapy necessitates better delivery of chemotherapeutics to the tumor. Nanoparticles can load higher amounts of drug and improve delivery to tumors, increasing the efficacy of treatment. Polymeric nanoparticles, in particular, have been used extensively for chemotherapeutic delivery. This review describes the efforts made to deliver combination chemotherapies and inhibit oncogenic pathways using polymeric drug delivery systems. Combinations of chemotherapeutics with other drugs or small interfering RNA (siRNA) combinations have been summarized. Special attention is given to the delivery of drug combinations that involve either paclitaxel or doxorubicin, two popular chemotherapeutics in clinic. Attempts to inhibit specific pathways for oncotherapy have also been described. These include inhibition of oncogenic pathways (including those involving HER2, EGFR, MAPK, PI3K/Akt, STAT3, and HIF-1α), augmentation of apoptosis by inhibiting anti-apoptosis proteins (Bcl-2, Bcl-xL, and survivin), and targeting dysregulated pathways such as Wnt/β-catenin and Hedgehog.

Psoralen-loaded lipid-polymer hybrid nanoparticles enhance doxorubicin efficacy in multidrug-resistant HepG2 cells

Background

Psoralen (PSO), a major active component of Psoralea corylifolia, has been shown to overcome multidrug resistance in cancer. A drug carrier comprising a lipid-monolayer shell and a biodegradable polymer core for sustained delivery and improved efficacy of drug have exhibited great potential in efficient treatment of cancers.

Methods

The PSO-loaded lipid polymer hybrid nanoparticles were prepared and characterized. In vitro cytotoxicity assay, cellular uptake, cell cycle analysis, detection of ROS level and mitochondrial membrane potential (ΔΨm) and western blot were performed.

Results

The P-LPNs enhanced the cytotoxicity of doxorubicin (DOX) 17-fold compared to free DOX in multidrug resistant HepG2/ADR cells. Moreover, P-LPNs displayed pro-apoptotic activity, increased levels of ROS and depolarization of ΔΨm. In addition, there were no signifi-cant effects on cellular uptake of DOX, cell cycle arrest, or the expression of P-glycoprotein. Mechanistic studies suggested that P-LPNs enhanced DOX cytotoxicity by increased release of cytochrome c and enhanced caspase3 cleavage, causing apoptosis in HepG2/ADR cells.

Conclusion

The lipid-polymer hybrid nanoparticles can be considered a powerful and promising drug delivery system for effective cancer chemotherapy.

Polymer-lipid hybrid nanoparticles: A novel drug delivery system for enhancing the activity of Psoralen against breast cancer

A polymer-lipid hybrid nanocarrier was developed to encapsulate psoralen (PSO) to improve its water solubility and bioavailability. The effects of PSO-loaded polymer-lipid hybrid nanoparticles (PSO-PLNs) on breast cancer MCF-7 cells were investigated. PSO-PLNs were prepared through a nanoprecipitation method and were optimized by a central composite design-response surface methodology using particle size and entrapment efficiency as indices. Dynamic light scattering and transmission electron microscopy analysis confirmed the physicochemical characterizations of PSO-PLNs, which had an average size of 93.44 ± 2.39 nm and a zeta potential of -27.63 ± 0.31 mV. In vitro drug release of PSO-PLNs was evaluated using dialysis and showed a delayed release compared with free PSO. The in vivo anticancer efficiency of PSO-PLNs was appreciated using a MCF-7 breast tumor model. Administration of PSO-PLNs showed similar antitumor efficacy but lower toxicity compared with doxorubicin. Our designed nanocarriers successfully optimized the pharmacokinetics of PSO via improved systemic delivery.

Application of a Quality-By-Design Approach to Optimise Lipid-Polymer Hybrid Nanoparticles Loaded with a Splice-Correction Antisense Oligonucleotide: Maximising Loading and Intracellular Delivery

BACKGROUND

Antisense oligonucleotides (ASOs) are promising therapeutics for specific modulation of cellular RNA function. However, ASO efficacy is compromised by inefficient intracellular delivery. Lipid-polymer hybrid nanoparticles (LPNs) are attractive mediators of intracellular ASO delivery due to favorable colloidal stability and sustained release properties.

METHODS

LPNs composed of cationic lipidoid 5 (L₅) and poly(DL-lactic-co-glycolic acid) were studied for delivery of an ASO mediating splice correction of a luciferase gene transcript (Luc-ASO). Specific purposes were: (i) to increase the mechanistic understanding of factors determining the loading of ASO in LPNs, and (ii) to optimise the LPNs and customise them for Luc-ASO delivery in HeLa pLuc/705 cells containing an aberrant luciferase gene by using a quality-by-design approach. Critical formulation variables were linked to critical quality attributes (CQAs) using risk assessment and design of experiments, followed by delineation of an optimal operating space (OOS).

RESULTS

A series of CQAs were identified based on the quality target product profile. The L₅ content and L₅:Luc-ASO ratio (w/w) were determined as critical formulation variables, which were optimised systematically. The optimised Luc-ASO-loaded LPNs, defined from the OOS, displayed high loading and mediated splice correction at well-tolerated, lower doses as compared to those required for reference L₅-based lipoplexes, L₅-modified stable nucleic acid lipid nanoparticles or LPNs modified with dioleoyltrimethylammonium propane (conventional cationic lipid).

CONCLUSIONS

The optimal Luc-ASO-loaded LPNs represent a robust formulation that mediates efficient intracellular delivery of Luc-ASO. This opens new avenues for further development of LPNs as a broadly applicable technology platform for delivering nucleic acid cargos intracellularly.

Lipomers (Lipid-polymer Hybrid Particles) of Vardenafil Hydrochloride: a Promising Dual Platform for Modifying the Drug Release Rate and Enhancing Its Oral Bioavailability

Vardenafil hydrochloride is commonly used for the curing of erectile dysfunction. VAR suffers certain limitations: (i) short elimination half-life (4-5 h), (ii) low aqueous solubility (0.11 mg/mL), (iii) susceptibility to extensive first-pass metabolism and drug efflux transporters (P-glycoprotein), and (iv) limited (15%) oral bioavailability. The current study focused on the development of VAR lipomers as promising modified release systems able to enhance oral bioavailability. VAR-lipomers (lipid-polymer complexes) were successfully developed by a modified precipitation technique employing a lipid (polyglyceryl-6-distearate or glyceryl tristearate) and an amphiphilic polymer (Gantrez®). Three VAR:lipid ratios [1:1, 1:2, and 1:3] and three VAR:Gantrez® ratios [4:1, 2:1, and 1:1] were investigated. Solid-state characterization studies involved differential scanning calorimetry (DSC), X-ray diffraction (XRD), and Fourier-transform infrared (FT-IR) spectroscopy. The systems were assessed for particle size, polydispersity index (PDI), zeta-potential, VAR entrapment-efficiency (EE%), morphology, and VAR released % after 2 h (Q_2h) and 8 h (Q_8h). The best-achieved system (the highest desirability) was promoted for pharmacokinetic studies in fasted rabbits. Statistical analysis of data revealed that L9 system (PGDS, VAR, and Gantrez®; 3:1:1, respectively) had the highest desirability (0.85) with respect to spherical particle size (622.15 nm), PDI (0.11), zeta-potential (-27.90 mV), EE% (62.80%), Q_2h (43.45%), and Q_8h (77.40%). With respect to Levitra® tablets, the significantly higher relative bioavailability (170%), delayed T_max, and extended MRT_(0-∞) clarified the dual ability of L9 system. Lipomers are emerging systems capable of modifying the rate of VAR release and promoting its oral bioavailability.

Preparation of psoralen polymer-lipid hybrid nanoparticles and their reversal of multidrug resistance in MCF-7/ADR cells

Multidrug resistance (MDR) is the leading cause of failure for breast cancer in the clinic. Thus far, polymer-lipid hybrid nanoparticles (PLN) loaded chemotherapeutic agents has been used to overcome MDR in breast cancer. In this study, we prepared psoralen polymer-lipid hybrid nanoparticles (PSO-PLN) to reverse drug resistant MCF-7/ADR cells in vitro and in vivo. PSO-PLN was prepared by the emulsification evaporation-low temperature solidification method. The formulation, water solubility and bioavailability, particle size, zeta potential and entrapment efficiency, and in vitro release experiments were optimized in order to improve the activity of PSO to reverse MDR. Optimal formulation: soybean phospholipids 50 mg, poly(lactic-co-glycolic) acid (PLGA) 15 mg, PSO 3 mg, and Tween-80 1%. The PSO-PLN possessed a round appearance, uniform size, exhibited no adhesion. The average particle size was 93.59 ± 2.87 nm, the dispersion co-efficient was 0.249 ± 0.06, the zeta potential was 25.47 ± 2.84 mV. In vitro analyses revealed that PSO resistance index was 3.2, and PSO-PLN resistance index was 5.6, indicating that PSO-PLN versus MCF-7/ADR reversal effect was significant. Moreover, PSO-PLN is somewhat targeted to the liver, and has an antitumor effect in the xenograft model of drug-resistant MCF-7/ADR cells. In conclusion, PSO-PLN not only reverses MDR but also improves therapeutic efficiency by enhancing sustained release of PSO.

Lipid-polymer hybrid nanocarrier-mediated cancer therapeutics: current status and future directions

The new generation of nanoparticles (NPs) encompass attributes of lipids and polymers and are referred to as 'lipid-polymer hybrid nanoparticles' (LPHNPs). LPHNPs have helped shed light on the mechanisms involved in targeted and non-specific drug delivery. Research has also highlighted the opportunities and challenges faced by the use of nanomedicine as personalized therapies in oncology. Here, we review the development of LPHNPs as cancer therapeutics, focusing on the methods deployed for enhancing the targeting efficiency and applications of LPHNPs.

Importance of integrating nanotechnology with pharmacology and physiology for innovative drug delivery and therapy - an illustration with firsthand examples

Nanotechnology has been applied extensively in drug delivery to improve the therapeutic outcomes of various diseases. Tremendous efforts have been focused on the development of novel nanoparticles and delineation of the physicochemical properties of nanoparticles in relation to their biological fate and functions. However, in the design and evaluation of these nanotechnology-based drug delivery systems, the pharmacology of delivered drugs and the (patho-)physiology of the host have received less attention. In this review, we discuss important pharmacological mechanisms, physiological characteristics, and pathological factors that have been integrated into the design of nanotechnology-enabled drug delivery systems and therapies. Firsthand examples are presented to illustrate the principles and advantages of such integrative design strategies for cancer treatment by exploiting 1) intracellular synergistic interactions of drug-drug and drug-nanomaterial combinations to overcome multidrug-resistant cancer, 2) the blood flow direction of the circulatory system to maximize drug delivery to the tumor neovasculature and cells overexpressing integrin receptors for lung metastases, 3) endogenous lipoproteins to decorate nanocarriers and transport them across the blood-brain barrier for brain metastases, and 4) distinct pathological factors in the tumor microenvironment to develop pH- and oxidative stress-responsive hybrid manganese dioxide nanoparticles for enhanced radiotherapy. Regarding the application in diabetes management, a nanotechnology-enabled closed-loop insulin delivery system was devised to provide dynamic insulin release at a physiologically relevant time scale and glucose levels. These examples, together with other research results, suggest that utilization of the interplay of pharmacology, (patho-)physiology and nanotechnology is a facile approach to develop innovative drug delivery systems and therapies with high efficiency and translational potential.

Diruthenium(ii,iii) metallodrugs of ibuprofen and naproxen encapsulated in intravenously injectable polymer-lipid nanoparticles exhibit enhanced activity against breast and prostate cancer cells

A unique class of diruthenium(ii,iii) metallodrugs containing non-steroidal anti-inflammatory drug (NSAID), Ru₂(NSAID), have been reported to show anticancer activity in glioma models in vitro and in vivo. This work reports the encapsulation of the lead metallodrug of ibuprofen (HIbp), [Ru₂(Ibp)₄Cl] or RuIbp, and also of the new analogue of naproxen (HNpx), [Ru₂(Npx)₄Cl] or RuNpx, in novel intravenously (i.v.) injectable solid polymer-lipid nanoparticles (SPLNs). A rationally selected composition of lipids/polymers rendered nearly spherical Ru₂(NSAID)-SPLNs with a mean size of 120 nm and zeta potential of about -20 mV. The Ru₂(NSAID)-SPLNs are characterized by spectroscopic techniques and the composition in terms of ruthenium-drug species is analyzed by mass spectrometry. The metallodrug-loaded nanoparticles showed high drug loading (17-18%) with ∼100% drug loading efficiency, and good colloidal stability in serum at body temperature. Fluorescence-labeled SPLNs were taken up by the cancer cells in a time- and energy-dependent manner as analyzed by confocal microscopy and fluorescence spectrometry. The Ru₂(NSAID)-SPLNs showed enhanced cytotoxicity (IC₅₀ at 60-100 μmol L^-1 ) in relation to the corresponding Ru₂(NSAID) metallodrugs in breast (EMT6 and MDA-MB-231) and prostate (DU145) cancer cells in vitro. The cell viability of both metallodrug nanoformulations is also compared with those of the parent NSAIDs, HIbp and HNpx, and their corresponding NSAID-SPLNs. In vivo and ex vivo fluorescence imaging revealed good biodistribution and high tumor accumulation of fluorescence-labeled SPLNs following i.v. injection in an orthotopic breast tumor model. The enhanced anticancer activity of the metallodrug-loaded SPLNs in these cell lines can be associated with the advantages of the nanoformulations, assigned mainly to the stability of the colloidal nanoparticles suitable for i.v. injection and enhanced cellular uptake. The findings of this work encourage future in vivo efficacy studies to further exploit the potential of the novel Ru₂(NSAID)-SPLN nanoformulations for clinical application.

Beyond liposomes: Recent advances on lipid based nanostructures for poorly soluble/poorly permeable drug delivery

Solid lipid nanoparticle (SLN), nanostructured lipid carriers (NLC) and hybrid nanoparticles, have gained increasing interest as drug delivery systems because of their potential to load and release drugs from the Biopharmaceutical classification system (BCS) of class II (low solubility and high permeability) and of class IV (low solubility and low permeability). Lipid properties (e.g. high solubilizing potential, biocompatibility, biotolerability, biodegradability and distinct route of absorption) contribute for the improvement of the bioavailability of these drugs for a set of administration routes. Their interest continues to grow, as translated by the number of patents being field worldwide. This paper discusses the recent advances on the use of SLN, NLC and lipid-polymer hybrid nanoparticles for the loading of lipophilic, poorly water-soluble and poorly permeable drugs, being developed for oral, topical, parenteral and ocular administration, also discussing the industrial applications of these systems. A review of the patents filled between 2014 and 2017, concerning the original inventions of lipid nanocarriers, is also provided.

Lipid-polymer hybrid nanoparticles: Development & statistical optimization of norfloxacin for topical drug delivery system

Poly lactic acid is a biodegradable, biocompatible, and non-toxic polymer, widely used in many pharmaceutical preparations such as controlled release formulations, parenteral preparations, surgical treatment applications, and tissue engineering. In this study, we prepared lipid-polymer hybrid nanoparticles for topical and site targeting delivery of Norfloxacin by emulsification solvent evaporation method (ESE). The design of experiment (DOE) was done by using software to optimize the result, and then a surface plot was generated to compare with the practical results. The surface morphology, particle size, zeta potential and composition of the lipid-polymer hybrid nanoparticles were characterized by SEM, TEM, AFM, and FTIR. The thermal behavior of the lipid-polymer hybrid nanoparticles was characterized by DSC and TGA. The prepared lipid-polymer hybrid nanoparticles of Norfloxacin exhibited an average particle size from 178.6 ± 3.7 nm to 220.8 ± 2.3 nm, and showed very narrow distribution with polydispersity index ranging from 0.206 ± 0.36 to 0.383 ± 0.66. The surface charge on the lipid-polymer hybrid nanoparticles were confirmed by zeta potential, showed the value from +23.4 ± 1.5 mV to +41.5 ± 3.4 mV. An Antimicrobial study was done against Staphylococcus aureus and Pseudomonas aeruginosa, and the lipid-polymer hybrid nanoparticles showed potential activity against these two. Lipid-polymer hybrid nanoparticles of Norfloxacin showed the %cumulative drug release of 89.72% in 24 h. A stability study of the optimized formulation showed the suitable condition for the storage of lipid-polymer hybrid nanoparticles was at 4 ± 2 °C/60 ± 5% RH. These results illustrated high potential of lipid-polymer hybrid nanoparticles Norfloxacin for usage as a topical antibiotic drug carriers.

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Efficient topical drug delivery systems of norfloxacin have been synthesized.

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Norfloxacin loaded to the core of lipid- polymer hybrid nanoparticles were prepared.

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The formulations were optimized by factorial design and characterization techniques.

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A unique formulation of norfloxacin that offer prolonged and control delivery.

A Review of the Structure, Preparation, and Application of NLCs, PNPs, and PLNs

Nanostructured lipid carriers (NLCs) are modified solid lipid nanoparticles (SLNs) that retain the characteristics of the SLN, improve drug stability and loading capacity, and prevent drug leakage. Polymer nanoparticles (PNPs) are an important component of drug delivery. These nanoparticles can effectively direct drug delivery to specific targets and improve drug stability and controlled drug release. Lipid–polymer nanoparticles (PLNs), a new type of carrier that combines liposomes and polymers, have been employed in recent years. These nanoparticles possess the complementary advantages of PNPs and liposomes. A PLN is composed of a core–shell structure; the polymer core provides a stable structure, and the phospholipid shell offers good biocompatibility. As such, the two components increase the drug encapsulation efficiency rate, facilitate surface modification, and prevent leakage of water-soluble drugs. Hence, we have reviewed the current state of development for the NLCs’, PNPs’, and PLNs’ structures, preparation, and applications over the past five years, to provide the basis for further study on a controlled release drug delivery system.

Design of nanocarriers for nanoscale drug delivery to enhance cancer treatment using hybrid polymer and lipid building blocks

Polymer-lipid hybrid nanoparticles (PLN) are an emerging nanocarrier platform made from building blocks of polymers and lipids. PLN integrate the advantages of biomimetic lipid-based nanoparticles (i.e. solid lipid nanoparticles and liposomes) and biocompatible polymeric nanoparticles. PLN are constructed from diverse polymers and lipids and their numerous combinations, which imparts PLN with great versatility for delivering drugs of various properties to their nanoscale targets. PLN can be classified into two types based on their hybrid nanoscopic structure and assembly methods: Type-I monolithic matrix and Type-II core-shell systems. This article reviews the history of PLN development, types of PLN, lipid and polymer candidates, fabrication methods, and unique properties of PLN. The applications of PLN in delivery of therapeutic or imaging agents alone or in combination for cancer treatment are summarized and illustrated with examples. Important considerations for the rational design of PLN for advanced nanoscale drug delivery are discussed, including selection of excipients, synthesis processes governing formulation parameters, optimization of nanoparticle properties, improvement of particle surface functionality to overcome macroscopic, microscopic and cellular biological barriers. Future directions and potential clinical translation of PLN are also suggested.

Nanomedicine-Mediated Combination Drug Therapy in Tumor

Background:

Combined chemotherapy has gradually become one of the conventional methods of cancer treatment due to the limitation of monotherapy. However, combined chemotherapy has several drawbacks that may lead to treatment failure because drug synergy cannot be guaranteed, achievement of the optimal synergistic drug ratio is difficult, and drug uptake into the tumor is inconsistent. Nanomedicine can be a safe and effective form of drug delivery, which may address the problems associated with combination chemotherapy.

Objective:

This review summarizes the recent research in this area, including the use of nanoparticles, liposomes, lipid-polymer hybrid nanoparticles, and polymeric micelles, and provides new approach for combined chemotherapy.

Methods:

By collecting and referring to the related literature in recent years.

Results:

Compared with conventional drugs, nanomedicine has the following advantages: it increases bioavailability of poorly soluble drugs, prolongs drug circulation timein vivo, and permits multiple drug loading, all of which could improve drug efficacy and reduce toxicity. Furthermore, nanomedicine can maintain the synergistic ratio of the drugs; deliver the drugs to the tumor at the same time, such that two or more drugs of tumor treatment achieve synchronization in time and space; and alter the pharmacokinetics and distribution profilein vivosuch that these are dependent on nanocarrier properties (rather than being dependent on the drugs themselves).

Conclusion:

Therefore, nanomedicine-mediated combination drug therapy is promising in the treatment of tumors.

Potential applications of nanoparticles in cancer immunotherapy

In recent years considerable progress has been made in the field of cancer immunotherapy whereby treatments that modulate the body's own immune system are used to combat cancer. This has the potential to not only elicit strong anti-cancer immune responses which can break pre-existing tolerance and help promote tumor regression, but could also induce immunological memory which may help prevent tumor recurrence. In order to ensure effective delivery of immunotherapeutic agents, such as vaccines, checkpoint inhibitors, chemotherapeutic agents and nucleic acids, a safe and effective delivery system is often required. One such approach is the use of multifunctional nanoparticles (NPs), such as liposomes, polymers, micelles, dendrimers, inorganic NPs, and hybrid NPs, which have the potential to combine the delivery of a diverse range of therapeutic immunomodulators thereby increasing the efficacy of tumor cell killing. This review focuses on recent progress in NP-mediated immunotherapy for the treatment of cancer.

Amphiphilic polymers formed from ring-opening polymerization: a strategy for the enhancement of gene delivery

Ring-opening polymerization was found to be a promising strategy to improve the transfection efficiency and serum tolerance of cationic lipids.

Nanomedicine of synergistic drug combinations for cancer therapy - Strategies and perspectives

Nanomedicine of synergistic drug combinations has shown increasing significance in cancer therapy due to its promise in providing superior therapeutic benefits to the current drug combination therapy used in clinical practice. In this article, we will examine the rationale, principles, and advantages of applying nanocarriers to improve anticancer drug combination therapy, review the use of nanocarriers for delivery of a variety of combinations of different classes of anticancer agents including small molecule drugs and biologics, and discuss the challenges and future perspectives of the nanocarrier-based combination therapy. The goal of this review is to provide better understanding of this increasingly important new paradigm of cancer treatment and key considerations for rational design of nanomedicine of synergistic drug combinations for cancer therapy.