Tumor Specific Delivery and Therapy by Double-Targeted Nanostructured Lipid Carriers with Anti-VEGFR-2 Antibody

Smart nanoparticles for cancer therapy

Smart nanoparticles, which can respond to biological cues or be guided by them, are emerging as a promising drug delivery platform for precise cancer treatment. The field of oncology, nanotechnology, and biomedicine has witnessed rapid progress, leading to innovative developments in smart nanoparticles for safer and more effective cancer therapy. In this review, we will highlight recent advancements in smart nanoparticles, including polymeric nanoparticles, dendrimers, micelles, liposomes, protein nanoparticles, cell membrane nanoparticles, mesoporous silica nanoparticles, gold nanoparticles, iron oxide nanoparticles, quantum dots, carbon nanotubes, black phosphorus, MOF nanoparticles, and others. We will focus on their classification, structures, synthesis, and intelligent features. These smart nanoparticles possess the ability to respond to various external and internal stimuli, such as enzymes, pH, temperature, optics, and magnetism, making them intelligent systems. Additionally, this review will explore the latest studies on tumor targeting by functionalizing the surfaces of smart nanoparticles with tumor-specific ligands like antibodies, peptides, transferrin, and folic acid. We will also summarize different types of drug delivery options, including small molecules, peptides, proteins, nucleic acids, and even living cells, for their potential use in cancer therapy. While the potential of smart nanoparticles is promising, we will also acknowledge the challenges and clinical prospects associated with their use. Finally, we will propose a blueprint that involves the use of artificial intelligence-powered nanoparticles in cancer treatment applications. By harnessing the potential of smart nanoparticles, this review aims to usher in a new era of precise and personalized cancer therapy, providing patients with individualized treatment options.

Surface Immobilization of Anti-VEGF Peptide on SPIONs for Antiangiogenic and Targeted Delivery of Paclitaxel in Non-Small-Cell Lung Carcinoma

A design has been established for the surface decoration of superparamagnetic iron oxide nanoparticles (SPIONs) with anti-vascular endothelial growth factor peptide, HRH, to formulate a targeted paclitaxel (PTX) delivery nanosystem with notable tumor targetability and antiangiogenic activity. The design methodology included (i) tandem surface functionalization via coupling reactions, (ii) pertinent physicochemical characterization, (iii) in vitro assessment of drug release, anti-proliferative activity, and quantification of vascular endothelial growth factor A (VEGF-A) levels, and (iv) in vivo testing using a lung tumor xenograft mouse model. Formulated CLA-coated PTX-SPIONs@HRH depicted a size and surface charge of 108.5 ± 3.5 nm and -30.4 ± 2.3 mV, respectively, and a quasi-spherical shape relative to pristine SPIONs. Fourier transform infrared (FTIR) analysis and estimation of free carboxylic groups supported the preparation of the CLA-coated PTX-SPIONs@HRH. CLA-coated PTX-SPIONs@HRH exhibited high PTX loading efficiency (98.5%) and sustained release in vitro, with a marked dose dependent anti-proliferative activity in A549 lung adenocarcinoma cells, complimented by an enhanced cellular uptake. CLA-coated PTX-SPIONs@HRH significantly reduced secretion levels of VEGF-A in human dermal microvascular endothelial cells from 46.9 to 35.6 pg/mL compared to untreated control. A 76.6% tumor regression was recorded in a lung tumor xenograft mouse model following intervention with CLA-coated PTX-SPIONs@HRH, demonstrating tumor targetability and angiogenesis inhibition. CLA-coated PTX-SPIONs@HRH enhanced the half-life of PTX by almost 2-folds and demonstrated a prolonged PTX plasma circulation time from a subcutaneous injection (SC). Thus, it is suggested that CLA-coated PTX-SPIONs@HRH could provide a potential effective treatment modality for non-small-cell lung carcinoma as a nanomedicine.

Solid Lipid Nanoparticles vs. Nanostructured Lipid Carriers: A Comparative Review

Solid-lipid nanoparticles and nanostructured lipid carriers are delivery systems for the delivery of drugs and other bioactives used in diagnosis, therapy, and treatment procedures. These nanocarriers may enhance the solubility and permeability of drugs, increase their bioavailability, and extend the residence time in the body, combining low toxicity with a targeted delivery. Nanostructured lipid carriers are the second generation of lipid nanoparticles differing from solid lipid nanoparticles in their composition matrix. The use of a liquid lipid together with a solid lipid in nanostructured lipid carrier allows it to load a higher amount of drug, enhance drug release properties, and increase its stability. Therefore, a direct comparison between solid lipid nanoparticles and nanostructured lipid carriers is needed. This review aims to describe solid lipid nanoparticles and nanostructured lipid carriers as drug delivery systems, comparing both, while systematically elucidating their production methodologies, physicochemical characterization, and in vitro and in vivo performance. In addition, the toxicity concerns of these systems are focused on.

Lipid Nanoparticles Functionalized with Antibodies for Anticancer Drug Therapy

Nanotechnology takes the lead in providing new therapeutic options for cancer patients. In the last decades, lipid-based nanoparticles-solid lipid nanoparticles (SLNs), nanostructured lipid carriers (NLCs), liposomes, and lipid-polymer hybrid nanoparticles-have received particular interest in anticancer drug delivery to solid tumors. To improve selectivity for target cells and, thus, therapeutic efficacy, lipid nanoparticles have been functionalized with antibodies that bind to receptors overexpressed in angiogenic endothelial cells or cancer cells. Most papers dealing with the preclinical results of antibody-conjugated nanoparticles claim low systemic toxicity and effective tumor inhibition, which have not been successfully translated into clinical use yet. This review aims to summarize the current "state-of-the-art" in anticancer drug delivery using antibody-functionalized lipid-based nanoparticles. It includes an update on promising candidates that entered clinical trials and some explanations for low translation success.

Targeted Molecular Imaging Probes Based on Magnetic Resonance Imaging for Hepatocellular Carcinoma Diagnosis and Treatment

Hepatocellular carcinoma (HCC) is the sixth most commonly malignant tumor and the third leading cause of cancer-related death in the world, and the early diagnosis and treatment of patients with HCC is core in improving its prognosis. The early diagnosis of HCC depends largely on magnetic resonance imaging (MRI). MRI has good soft-tissue resolution, which is the international standard method for the diagnosis of HCC. However, MRI is still insufficient in the diagnosis of some early small HCCs and malignant nodules, resulting in false negative results. With the deepening of research on HCC, researchers have found many specific molecular biomarkers on the surface of HCC cells, which may assist in diagnosis and treatment. On the other hand, molecular imaging has progressed rapidly in recent years, especially in the field of cancer theranostics. Hence, the preparation of molecular imaging probes that can specifically target the biomarkers of HCC, combined with MRI testing in vivo, may achieve the theranostic purpose of HCC in the early stage. Therefore, in this review, taking MR imaging as the basic point, we summarized the recent progress regarding the molecular imaging targeting various types of biomarkers on the surface of HCC cells to improve the theranostic rate of HCC. Lastly, we discussed the existing obstacles and future prospects of developing molecular imaging probes as HCC theranostic nanoplatforms.

Glioblastoma multiforme targeted delivery of docetaxel using bevacizumab-modified nanostructured lipid carriers impair in vitro cell growth and in vivo tumor progression

Glioblastoma multiforme (GBM) is the most common malignant brain cancer, characterized by high invasiveness and poor prognosis. Docetaxel (DTX) is a chemotherapeutic drug with promising anti-tumor properties. However, conventional intravenous formulations exhibit side effects of systemic biodistribution and low brain bioavailability, limiting their clinical use. The current work aimed to evaluate the effect of DTX-loaded nanostructured lipid carriers (NLC) functionalized with bevacizumab (BVZ-NLC-DTX) against GBM using in vitro and in vivo models. The NLC was obtained by the fusion-emulsification method followed by sonication, with narrow size distribution, negative zeta potential, and low polydispersity index. NLC showed DTX entrapment efficiency above 90%. BVZ coupling efficiency was 62% and BVZ integrity after functionalization was confirmed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Calorimetry studies confirmed thermal stability and molecular dispersion of DTX in the lipid matrix. NLC showed a sustained DTX release over 84 h. In vitro anti-tumor assays shown that BVZ-NLC-DTX selectively increased the cytotoxic of DTX in cells overexpressing VEGF (U87MG and A172), but not in peripheral blood mononuclear cells (PMBCs), promoting cell death by apoptosis. BVZ functionalization did not impair cellular uptake. An in vivo orthotopic rat model demonstrated that free-DTX was not capable of reducing tumor growth whereas BVZ-NLC-DTX reduced up to 70% tumor volume after 15-days of treatment. Therefore, this study contributes to understanding new nanotechnology-based vehicles capable of reaching the brain more efficiently and repurposing the use of anti-cancer drugs in GBM treatment.

The combination of MnO2@Lipo-coated gefitinib and bevacizumab inhibits the development of non-small cell lung cancer

It can be found from a large number of cancer treatments that use of anti-cancer drugs alone often presents low efficacy and high side effects. This study aims to develop a new drug carrier with tumor-specific response, controlled release in vivo and high tumor-suppressive property. Inorganic nano-materials MnO₂ with pH and glutathione (GSH, abundant in cancer cells) responsiveness were used to construct sustained-release functional nano-liposome to be an excellent in vivo pH-sensitive drug delivery system. Some hydrophilic MnO₂, gefitinib (Geb), and bevacizumab (Beb) were encapsulated in the phospholipid vesicles (liposomes), so as to integrate several anti-tumor drugs (MnO₂-PDA@Lipo@Geb@Beb) to achieve effective treatment of non-small cell lung cancer (NSCLC). Part of the MnO₂ nanorods on the lipid shell had the properties of pH and GSH responsiveness, which could further enhance anti-cancer efficacy. Cell assay results showed that MnO₂-PDA@Lipo@Geb@Beb nano-drug had an effective inhibition on A549 cell progression and showed excellent biocompatibility. In vivo results further confirmed that MnO₂-PDA@Lipo@Geb@Beb nano-drug could effectively inhibit the growth of NSCLC cells. Overall, it can be inferred from the above experimental results that the nanocomposite drug is expected to be widely used in the clinical application of lung cancer.

Application of Nanoparticles in the Treatment of Lung Cancer With Emphasis on Receptors

Lung cancer is one of the malignant tumors that has seen the most rapid growth in terms of morbidity and mortality in recent years, posing the biggest threat to people’s health and lives. In recent years, the nano-drug loading system has made significant progress in the detection, diagnosis, and treatment of lung cancer. Nanomaterials are used to specifically target tumor tissue to minimize therapeutic adverse effects and increase bioavailability. It is achieved primarily through two mechanisms: passive targeting, which entails the use of enhanced penetration and retention (EPR) effect, and active targeting, which entails the loading recognition ligands for tumor marker molecules onto nanomaterials. However, it has been demonstrated that the EPR effect is effective in rodents but not in humans. Taking this into consideration, researchers paid significant attention to the active targeting nano-drug loading system. Additionally, it has been demonstrated to have a higher affinity and specificity for tumor cells. In this review, it describes the development of research into active targeted nano-drug delivery systems for lung cancer treatment from the receptors’ or targets’ perspective. We anticipate that this study will help biomedical researchers use nanoparticles (NPs) to treat lung cancer by providing more and novel drug delivery strategies or solid ligands.

Antineoplastics Encapsulated in Nanostructured Lipid Carriers

Ideally, antineoplastic treatment aims to selectively eradicate cancer cells without causing systemic toxicity. A great number of antineoplastic agents (AAs) are available nowadays, with well-defined therapeutic protocols. The poor bioavailability, non-selective action, high systemic toxicity, and lack of effectiveness of most AAs have stimulated the search for novel chemotherapy protocols, including technological approaches that provide drug delivery systems (DDS) for gold standard medicines. Nanostructured lipid carriers (NLC) are DDS that contain a core of solid and lipid liquids stabilised by surfactants. NLC have high upload capacity for lipophilic drugs, such as the majority of AAs. These nanoparticles can be prepared with a diversity of biocompatible (synthetic or natural) lipid blends, administered by different routes and functionalised for targeting purposes. This review focused on the research carried out from 2000 to now, regarding NLC formulations for AAs (antimetabolites, antimitotics, alkylating agents, and antibiotics) encapsulation, with special emphasis on studies carried out in vivo. NLC systems for codelivery of AAs were also considered, as well as those for non-classical drugs and therapies (natural products and photosensitisers). NLC have emerged as powerful DDS to improve the bioavailability, targeting and efficacy of antineoplastics, while decreasing their toxic effect in the treatment of different types of cancer.

Tumor-targeted hyaluronic acid-mPEG modified nanostructured lipid carriers for cantharidin delivery: An in vivo and in vitro study

AIM

Cantharidin (CTD), the major component of the anti-cancer medicine obtained from Mylabris cichorii, exerts good inhibitory effects on several cancers, such as liver and breast cancer. However, owing to its toxicity, its oral administration can cause various adverse effects, limiting its clinical applications. Therefore, the development of a novel nano-drug delivery system for CTD would be highly beneficial.

METHODS

A nanostructured lipid carrier (NLC) was designed to actively target CTD to tumor cells using a hyaluronic acid (HA)-decorated copolymer (mPEG-NH2); the NLCs were called HA-mPEG-CTD-NLC. HA-mPEG was synthesized using amidation, and HA-mPEG-CTD-NLC was generated through ultrasonic emulsification in water. The mean hydrodynamic diameter of the particles was approximately 119.3 nm.

RESULTS

Pharmacokinetic studies revealed that the half-life of HA-mPEG-CTD-NLC and its area under the curve were higher than those of a CTD solution. Further, the plasma clearance rate of HA-mPEG-CTD-NLC was 0.41 times that of the CTD solution, implying a significantly prolonged drug retention time in vivo. Fluorescence in vivo endo-microscopy and optical in vivo imaging revealed that HA-mPEG-CTD-NLC had superior cytotoxicity and targeting efficacy against SMMC-7721 cells. An evaluation of the in vivo anti-tumor activity showed that HA-mPEG-CTD-NLC significantly inhibited tumor growth and prolonged survival in tumor-bearing mice, with a tumor inhibition rate of 65.96%.

CONCLUSIONS

Our results indicate that HA-mPEG-CTD-NLC may have great potential in liver cancer-targeted therapy.

Advancement in design of nanostructured lipid carriers for cancer targeting and theranostic application

BACKGROUND

Cancer development is associated with abnormal, uncontrolled cell growth and causes significant economic and social burdens to society. The global statistics of different cancers have been increasing because of the aging population, and the increasing prevalence of risk factors such as stress condition, overweight, changing reproductive patterns, and smoking. The prognosis of cancer treatment is high, if diagnosed in the early stage. Late-stage diagnosis, however, is still a big challenge for the clinician. The usual treatment scheme involves chemotherapy and surgery followed by radiotherapy.

SCOPE OF REVIEW

Chemotherapy is the most widely used therapeutic approach against cancer. However, it suffers from the major limitation of poor delivery of anticancer therapeutics to specific cancer-targeted tissues/cells.

MAJOR CONCLUSIONS

Nanomedicines, particularly nanostructured lipid carriers (NLCs) can improve the efficacy of encapsulated payload either through an active or passive targeting approach against different cancers. The targeted nanomedicine can be helpful in transporting drug carriers to the specifically tumor-targeted tissue/cells while sparing abstaining from the healthy tissue/cells. The active targeting utilizes the binding of a specific cancer ligand to the surface of the NLCs, which improves the therapeutic efficacy and safety of the cancer therapeutics.

GENERAL SIGNIFICANCE

This review shed light on the utilization of NLCs system for targeted therapy in different cancers. Furthermore, modification of NLCs as cancer theranostics is a recent advancement that is also discussed in the manuscript with a review of contemporary research carried out in this field.

Liposome surface modification by phospholipid chemical reactions

Liposomal systems are well known for playing an important role as drug carriers, presenting several therapeutic applications in different sectors, such as in drug delivery, diagnosis, and in many other academic areas. A novel class of this nanoparticle is the actively target liposome, which is constructed with the surface modified with appropriated molecules (or ligands) to actively bind a target molecule of certain cells, system, or tissue. There are many ways to functionalize these nanostructures, from non-covalent adsorption to covalent bond formation. In this review, we focus on the strategies of modifying liposomes by glycerophospholipid covalent chemical reaction. The approach used in this text summarizes the main reactions and strategies used in phospholipid modification that can be carried out by chemists and researchers from other areas. The knowledge of these methodologies is of great importance for planning new studies using this material and also for manipulating its properties.

Development and characterization of gel-in-water nanoemulsion as a novel drug delivery system

The effective delivery of anti-cancer drugs with minimal side effects and better therapeutic efficacy has remained an active area of research for many decades. Organogels have gained attention in recent years as potential drug delivery systems due to their high bioavailability, no first-pass metabolism and rapid action. Considering this, in the current study an organogel based nanoemulsion was developed aiming to effectively deliver hydrophobic drugs via encapsulation within in situ gellable organogel droplets, termed as gel-in-water (G/W) nanoemulsion. G/W nanoemulsion was prepared using a combination of lipiodol and organogelator 12-hydroxystearic acid (12-HSA) as inner gel phase; dispersed in water by ultrasonication and stabilized with polyoxyethylene hydrogenated castor oil (HCO-60) as a surfactant. The prepared nanoemulsion showed high drug loading efficiency (≈97%) with a mean diameter of 206 nm. Lower polydispersity index (PdI) value (≈0.1) suggests monodispersed nature of G/W nanoemulsion in the continuous phase. G/W nanoemulsion was found stable over six months in terms of particle size, zeta potential and pH at different storage temperatures. There was no cytotoxic effect of prepared G/W nanoemulsion on primary hepatocytes in vitro. In contrast, paclitaxel-loaded G/W showed a significant decrease in melanoma cell growth (*p < 0.05) both in vitro and in vivo. Our results support the hypothesis that organogel based nanoemulsions can be a promising drug delivery system.

Nanosystem functionalization strategies for prostate cancer treatment: a review

Prostate cancer (PC) has a high morbidity and mortality rate worldwide, and the current clinical guidelines can vary depending on the stage of the disease. Drug delivery nanosystems (DDNs) can improve biopharmaceutical properties of encapsulated anti-cancer drugs by modulating their release kinetics, improving physicochemical stability and reducing toxicity. DDN can also enhance the ability of specific targeting through surface modification by coupling ligands (antibodies, nucleic acids, peptides, aptamer, proteins), thus favouring the cell internalisation process by endocytosis. The purposes of this review are to describe the limitations in the treatment of PC, explore different functionalization such as polymeric, lipid and inorganic nanosystems aimed at the treatment of PC, and demonstrate the improvement of this modification for an active target, as alternative and promising candidates for new therapies.

Monoclonal Antibodies Carried in Drug Delivery Nanosystems as a Strategy for Cancer Treatment

Monoclonal antibodies carried in nanosystems have been extensively studied and reported as a promising tool for the treatment of various types of cancers. Monoclonal antibodies have great advantages for the treatment of cancer because their protein structure can bind to the target tissue; however, it has some challenges such as denaturation following heat exposure and extreme values of pH, temperature and solvents, the ability to undergo hydrolysis, oxidation and deamination and the formation of non-native aggregates, which compromise drug stability to a large extent. In addition to these characteristics, they suffer rapid elimination when in the blood, which results in a short half-life and the production of neutralizing antibodies, rendering the doses ineffective. These challenges are overcome with encapsulation in nanosystems (liposomes, polymer nanoparticles, cyclodextrins, solid lipid nanoparticles, nanostructured lipid carriers, dendrimers and micelles) due to the characteristics of improving solubility, permeability, and selectivity only with tumor tissue; with that, there is a decrease in side effects beyond controlled release, which is critical to improving the therapeutic efficacy of cancer treatment. The article was divided into different types of nanosystems, with a description of their definitions and applications in various types of cancers. Therefore, this review summarizes the use of monoclonal antibodies encapsulated in nanosystems and the description of clinical studies with biosimilars. Biosimilars are defined as products that are similar to monoclonal antibodies which are produced when the patent for the monoclonal antibodies expires.

Low-toxicity FePt nanoparticles for the targeted and enhanced diagnosis of breast tumors using few centimeters deep whole-body photoacoustic imaging

A considerable amount of early breast tumors grown at a depth over 2 cm in breast tissues. With high near-infrared absorption of iron-platinum (FePt) nanoparticles, we achieved few centimeters deep photoacoustic (PA) imaging for the diagnosis of breast tumors. The imaging depth can extend over 5 cm in chicken breast tissues at the low laser energy density of 20 mJ/cm² (≤ ANSI safety limit). After anti-VEGFR conjugation and the tail-vein injection, we validated their targeting on tumor sites by the confocal microscopy and PA imaging. Using a home-made whole-body in vivo PA imaging, we found that the nanoparticles were rapidly cleared away from the site of the tumor and majorly metabolized through the liver. These results validated the clinical potential of the FePt nanoparticles in the low-toxicity PA theragnosis of early breast cancer and showed the capacity of our whole-body PA imaging technique on monitoring the dynamic biodistribution of nanoparticles in the living body.

Lipid Drug Carriers for Cancer Therapeutics: An Insight into Lymphatic Targeting, P-gp, CYP3A4 Modulation and Bioavailability Enhancement

In the treatment of cancer, chemotherapy plays an important role though the efficacy of anti-cancer drug administered orally is limited, due to their poor solubility in physiological medium, inability to cross biological membrane, high Para-glycoprotein (P-gp) mediated drug efflux, and pre-systemic metabolism. These all factors cumulatively reduce drug exposure at the target site leading to multidrug resistance (MDR). Lipid based carriers systems has been explored to overcome solubility and permeability related issues of anti-cancer drugs. The lipid based formulations have also been reported to circumvent the effect of P-gp and CYP3A4. Further long chain triglycerides (LCT) has shown their ability to access Lymphatic route over Medium Chain Triglycerides, as the former has been extensively used for targeting anti-cancer drugs at proliferating cells through lymphatic route. Therefore this review tries to reflect the usefulness of lipid based drug carriers systems (viz. liposome, solid lipid nanoparticle, nano-lipid carriers, self-emulsifying, lipidic pro-drugs) in targeting lymphatic system and overcoming issues related to solubility and permeability of anti-cancer drugs. Moreover, we have also tried to reflect how critically lipid based carriers are important in maximizing therapeutic safety and efficacy of anti-cancer drugs.

Combinatory antitumor therapy by cascade targeting of a single drug

Combination therapy has shown its promise in the clinic for enhancing the efficacy of tumor treatment. However, the dose control of multiple drugs and their non-overlapping toxicity from different drugs are still great challenge. In this work, a single model drug, paclitaxel (PTX), is used to realize combination therapy and solve the problems mentioned above. Either PTX or its triphenylphosphine derivative (TPTX) is encapsulated in galactose-modified liposomes (GLips) to obtain GLips-P or GLips-TP, which are simply mixed in different ratios to finely control the proportion of PTX and TPTX. These mixed liposomes, GLips-P/TP, feature a cascade target delivery of PTX, from tissue to cell, and then to organelle. PTX plays a primary role to cause the cytotoxicity by microtubule bindings in cytoplasm, while TPTX is proved to increase the intracellular levels of caspase-3 and caspase-9 that cause apoptosis via a mitochondria-mediated pathway. Notably, GLips-P/TP 3:1 exhibited the significant drug synergy in both cytotoxicity assay of HepG2 cells and the treatment efficacy in Heps xenograft ICR mouse models. This work not only demonstrates the great promise of a cascade targeting delivery for precise tumor treatment, but also offers a novel platform to design combinatory therapy systems using a single drug.

Nanostructured Lipid Carriers for Delivery of Chemotherapeutics: A Review

The efficacy of current standard chemotherapy is suboptimal due to the poor solubility and short half-lives of chemotherapeutic agents, as well as their high toxicity and lack of specificity which may result in severe side effects, noncompliance and patient inconvenience. The application of nanotechnology has revolutionized the pharmaceutical industry and attracted increasing attention as a significant means for optimizing the delivery of chemotherapeutic agents and enhancing their efficiency and safety profiles. Nanostructured lipid carriers (NLCs) are lipid-based formulations that have been broadly studied as drug delivery systems. They have a solid matrix at room temperature and are considered superior to many other traditional lipid-based nanocarriers such as nanoemulsions, liposomes and solid lipid nanoparticles (SLNs) due to their enhanced physical stability, improved drug loading capacity, and biocompatibility. This review focuses on the latest advances in the use of NLCs as drug delivery systems and their preparation and characterization techniques with special emphasis on their applications as delivery systems for chemotherapeutic agents and different strategies for their use in tumor targeting.

Biotin anchored nanostructured lipid carriers for targeted delivery of doxorubicin in management of mammary gland carcinoma through regulation of apoptotic modulator

Mammary gland tumour has the highest incidence rate and mortality in women, worldwide. The present study envisaged a molecularly targeted nanostructured lipid carrier (NLCs) for doxorubicin (Dox) delivery capable of inducing cellular apoptosis in mammary gland tumour. NLCs were prepared utilizing Perilla frutescens oil (54-69% ω3-fatty acid) as liquid lipid to enhance entrapment of Dox through molecular ion pairing. Biotin decorated NLCs (b-Dox-NLCs) were evaluated in vitro and in vivo. The b-Dox-NLCs showed particle size of 105.2 ± 3.5 nm, zeta potential -35 ± 2 mV, entrapment 99.15 ± 1.71%, drug content 19.67 ± 2.6 mg.g-1, biotin content 5.85 ± 0.64 µg.g-1 and drug release 98.67 ± 2.43% (facilitated by acidic microenvironment) respectively. MTT assay and Flow cytometric analysis revealed higher anti-proliferative capability of b-Dox-NLCs to force apoptosis in MCF-7 cell line vis-à-vis marketed Dox, evidenced by reactive oxygen species level and mitochondrial membrane potential mediated apoptosis. Enhanced antitumor targeting, therapeutic safety and efficacy was exhibited by b-Dox-NLCs, as investigated through tumour volume, animal survival, weight variation, cardiotoxicity and biodistribution studies in 7,12-Dimethylbenz[a]anthracene induced mammary gland tumour. Immunoblotting assay demonstrated b-Dox-NLCs downregulated anti-apoptotic proteins, i.e. bcl-2, MMP-9 while upregulated pro-apoptotic proteins, i.e. caspase-9, p16 and BAX. The experimental results suggest that biotinylated ω3-fatty acid augmented NLCs loaded with Dox are capable of inducing programmed cell death in mammary tumour and can be utilized as safe and effective delivery system with enhanced potential for mammary gland carcinoma therapy.

The Application of Nanotechnology in the Codelivery of Active Constituents of Plants and Chemotherapeutics for Overcoming Physiological Barriers during Antitumor Treatment

Antitumor therapy using a combination of drugs has shown increased clinical efficacy. Active constituents derived from plants can offer several advantages, such as high efficiacy, low toxicity, extensive effects, and multiple targets. At present, the combination of plants' active constituents and chemotherapeutic drugs has attracted increased attention. Nanodrug delivery systems (NDDSs) have been widely used in tumor-targeted therapy because of their efficacy of delivering antitumor drugs. The in vivo process of tumor-targeted NDDSs has several steps. They include blood circulation, tumor accumulation and penetration, target cell internalization and uptake, and drug release and drug response. In each step, NDDSs encounter multiple barriers that prevent their effective delivery to target sites. Studies have been performed to find alternative strategies to overcome these barriers. We reviewed the recent progress of codelivery of active constituents of plants and chemotherapeutics using NDDSs. Progress into transversing the physiological barriers for more effective in vivo antitumor delivery will be discussed in this review.

Surface engineering of nanomaterials with phospholipid-polyethylene glycol-derived functional conjugates for molecular imaging and targeted therapy

In recent years, phospholipid-polyethylene glycol-derived functional conjugates have been widely employed to decorate different nanomaterials, due to their excellent biocompatibility, long blood circulation characteristics, and specific targeting capability. Numerous in vivo studies have demonstrated that nanomedicines peripherally engineered with phospholipid-polyethylene glycol-derived functional conjugates show significantly increased selective and efficient internalization by target cells/tissues. Targeting moieties including small-molecule ligands, peptides, proteins, and antibodies are generally conjugated onto PEGylated phospholipids to decorate liposomes, micelles, hybrid nanoparticles, nanocomplexes, and nanoemulsions for targeted delivery of diagnostic and therapeutic agents to diseased sites. In this review, the synthesis methods of phospholipid-polyethylene glycol-derived functional conjugates, biophysicochemical properties of nanomedicines decorated with these conjugates, factors dominating their targeting efficiency, as well as their applications for in vivo molecular imaging and targeted therapy were summarized and discussed.

Brain targeted delivery of anticancer drugs: prospective approach using solid lipid nanoparticles

A brain tumour is amongst most devastating and challenging condition to overcome with suitable treatment as the drug has to cross the blood-brain barrier (BBB) with several physiological barriers like opsonisation by the reticuloendothelial system. Presently various techniques such as surgical, chemotherapeutic agents, and radiotherapy techniques have performed to extend the lifespan of patients diagnosed with glioblastoma, which did not maximise the overall survival of patients with a tumour. Nanotechnology is relied upon to diminish the requirement for intrusive methods for conveyance of therapeutics to the central nervous system. Colloidal nanocarriers sizing range 1-1000 nm have been utilised to cross BBB delivers the drug at cell levels with enhanced bioavailability and reduced toxicity. However, solid lipid nanoparticles (SLNs) are considered a highly flexible carrier for more successful remedially in brain tumour. The treatment of a brain tumour via SLNs is gaining greater potency due to its inimitable size and lipidic nature. This review focuses and represents the current strategies of SLNs in the brain tumour treatment with appropriate techniques adopted are highlighted. Based on this review, the authors concluded that SLNs embrace exclusive promising lipidic nanocarrier that could be utilised to target a brain tumour effectively.

Sterically Stabilized RIPL Peptide-Conjugated Nanostructured Lipid Carriers: Characterization, Cellular Uptake, Cytotoxicity, and Biodistribution

As a platform for hepsin-specific drug delivery, we previously prepared IPLVVPLRRRRRRRRC peptide (RIPL)-conjugated nanostructured lipid carriers (RIPL-NLCs) composed of Labrafil® M 1944 CS (liquid oil) and Precirol® ATO 5 (solid lipid). In this study, to prevent the recognition by the mononuclear phagocyte system, polyethylene glycol (PEG)-modified RIPL-NLCs (PEG-RIPL-NLCs) were prepared using PEG3000 at different grafting ratios (1, 5, and 10 mole %). All prepared NLCs showed a homogeneous dispersion (130⁻280 nm), with zeta potentials varying from -18 to 10 mV. Docetaxel (DTX) was successfully encapsulated in NLCs: encapsulation efficiency (93⁻95%); drug-loading capacity (102⁻109 µg/mg). PEG-RIPL-NLCs with a grafting ratio of 5% PEG or higher showed significantly reduced protein adsorption and macrophage phagocytosis. The uptake of PEG(5%)-RIPL-NLCs by cancer cell lines was somewhat lower than that of RIPL-NLCs because of the PEG-induced steric hindrance; however, the uptake level of PEG-RIPL-NLCs was still greater than that of plain NLCs. In vivo biodistribution was evaluated after tail vein injection of NLCs to normal mice. Compared to RIPL-NLCs, PEG(5%)-RIPL-NLCs showed lower accumulation in the liver, spleen, and lung. In conclusion, we found that PEG(5%)-RIPL-NLCs could be a promising nanocarrier for selective drug targeting with a high payload of poorly water-soluble drugs.

Bioengineered cellular and cell membrane-derived vehicles for actively targeted drug delivery: So near and yet so far

Cellular carriers for drug delivery are attractive alternatives to synthetic nanoparticles owing to their innate homing/targeting abilities. Here, we review molecular interactions involved in the homing of Mesenchymal stem cells (MSCs) and other cell types to understand the process of designing and engineering highly efficient, actively targeting cellular vehicles. In addition, we comprehensively discuss various genetic and non-genetic strategies and propose futuristic approaches of engineering MSC homing using micro/nanotechnology and high throughput small molecule screening. Most of the targeting abilities of a cell come from its plasma membrane, thus, efforts to harness cell membranes as drug delivery vehicles are gaining importance and are highlighted here. We also recognize and report the lack of detailed characterization of cell membranes in terms of safety, structural integrity, targeting functionality, and drug transport. Finally, we provide insights on future development of bioengineered cellular and cell membrane-derived vesicles for successful clinical translation.

RIPL peptide-conjugated nanostructured lipid carriers for enhanced intracellular drug delivery to hepsin-expressing cancer cells

Background

To facilitate selective and enhanced drug delivery to hepsin (Hpn)-expressing cancer cells, RIPL peptide (IPLVVPLRRRRRRRRC, 16-mer)-conjugated nanostructured lipid carriers (RIPL-NLCs) were developed.

Methods

NLCs were prepared using a solvent emulsification-evaporation method and the RIPL peptide was conjugated to the maleimide-derivatized NLCs via the thiol-maleimide reaction. Employing a fluorescent probe (DiI), in vitro target-selective intracellular uptake behaviors were observed using fluorescence microscopy and flow cytometry. Separately, docetaxel (DTX) was encapsulated by pre-loading technique, then cytotoxicity and drug release were evaluated. In vivo antitumor efficacy was investigated in BALB/c nude mice with SKOV3 cell tumors after intratumoral injections of different DTX formulations at a dose equivalent to 10 mg/kg DTX.

Results

RIPL-NLCs showed positively charged nanodispersion, whereas NLCs were negatively charged. DTX was successfully encapsulated with an encapsulation efficiency and drug loading capacity of 95-98% and 44-46 µg/mg, respectively. DTX release was diffusion-controlled, revealing the best fit to the Higuchi equation. Cellular uptake of DiI-loaded RIPL-NLCs was 8.3- and 6.2-fold higher than that of DiI-loaded NLCs, in Hpn(+) SKOV3 and LNCaP cells, respectively. The translocation of RIPL-NLCs into SKOV3 cells was time-dependent with internalization within 1 h and distribution throughout the cytoplasm after 2 h. DTX-loaded RIPL-NLCs (DTX-RIPL-NLCs) revealed dose-dependent in vitro cytotoxicity, while drug-free formulations were non-cytotoxic. In SKOV3-bearing xenograft mouse model, DTX-RIPL-NLCs significantly inhibited tumor growth: the inhibition ratios of the DTX solution-treated and DTX-RIPL-NLC-treated groups were 61.4% and 91.2%, respectively, compared to those of the saline-treated group (control).

Conclusion

RIPL-NLCs are good candidates for Hpn-selective drug targeting with a high loading capacity of hydrophobic drug molecules.

Intracellular Protein Delivery System Using a Target-Specific Repebody and Translocation Domain of Bacterial Exotoxin

With the high efficacy of protein-based therapeutics and plenty of intracellular drug targets, cytosolic protein delivery in a cell-specific manner has attracted considerable attention in the field of precision medicine. Herein, we present an intracellular protein delivery system based on a target-specific repebody and the translocation domain of Pseudomonas aeruginosa exotoxin A. The delivery platform was constructed by genetically fusing an EGFR-specific repebody as a targeting moiety to the translocation domain, while a protein cargo was fused to the C-terminal end of the delivery platform. The delivery platform was revealed to efficiently translocate a protein cargo to the cytosol in a target-specific manner. We demonstrate the utility and potential of the delivery platform by showing a remarkable tumor regression with negligible toxicity in a xenograft mice model when gelonin was used as the cytotoxic protein cargo. The present platform can find wide applications to the cell-selective cytosolic delivery of diverse proteins in many areas.

Combination of nanotechnology with vascular targeting agents for effective cancer therapy

As a young science, nanotechnology promptly integrated into the current oncology practice. Accordingly, various nanostructure particles were developed to reduce drug toxicity and allow the targeted delivery of various diagnostic and therapeutic compounds to the cancer cells. New sophisticated nanosystems constantly emerge to improve the performance of current anticancer modalities. Targeting tumor vasculature is an attractive strategy to fight cancer. Though the idea was swiftly furthered from basic science to the clinic, targeting tumor vasculature had a limited potential in patients, where tumors relapse due to the development of multiple drug resistance and metastasis. The aim of this review is to discuss the advantages of nanosystem incorporation with various vascular targeting agents, including (i) endogen anti-angiogenic agents; (ii) inhibitors of angiogenesis-related growth factors; (iii) inhibitors of tyrosine kinase receptors; (iv) inhibitors of angiogenesis-related signaling pathways; (v) inhibitors of tumor endothelial cell-associated markers; and (vi) tumor vascular disrupting agents. We also review the efficacy of nanostructures as natural vascular targeting agents. The efficacy of each approach in cancer therapy is further discussed.

Design, synthesis, and evaluation of VEGFR-targeted macromolecular MRI contrast agent based on biotin-avidin-specific binding

Developing magnetic resonance imaging (MRI) contrast agents with high relaxivity and specificity was essential to increase MRI diagnostic sensitivity and accuracy. In this study, the MRI contrast agent, vascular endothelial growth factor receptor (VEGFR)-targeted poly (l-lysine) (PLL)-diethylene triamine pentacetate acid (DTPA)-gadolinium (Gd) (VEGFR-targeted PLL-DTPA-Gd, VPDG), was designed and prepared to enhance the MRI diagnosis capacity of tumor. Biotin-PLL-DTPA-Gd was synthesized first, then, VEGFR antibody was linked to biotin-PLL-DTPA-Gd using biotin-avidin reaction. In vitro cytotoxicity study results showed that VPDG had low toxicity to MCF-7 cells and HepG2 cells at experimental concentrations. In cell uptake experiments, VPDG could significantly increase the internalization rates (61.75%±5.22%) in VEGFR-positive HepG2 cells compared to PLL-DTPA-Gd (PDG) (25.16%±4.71%, P<0.05). In MRI studies in vitro, significantly higher T1 relaxivity (14.184 mM^-1 s^-1) was observed compared to Magnevist^® (4.9 mM^-1 s^-1; P<0.01). Furthermore, in vivo MRI study results showed that VPDG could significantly enhance the tumor signal intensity and prolong the diagnostic time (from <1 h to 2.5 h). These results indicated that macromolecular VPDG was a promising MRI contrast agent and held great potential for molecular diagnosis of tumor.

Improved Antitumor Efficacy of Hyaluronic Acid-Complexed Paclitaxel Nanoemulsions in Treating Non-Small Cell Lung Cancer

Paclitaxel (PTX) is a effectively chemotherapeutic agent which is extensively able to treat the non-small cell lung, pancreatic, breast and other cancers. But it is a practically insoluble drug with water solubility less than 1 μg/mL, which restricts its therapeutic application. To overcome the problem, hyaluronic acid-complexed paclitaxel nanoemulsions (HPNs) were prepared by ionic complexation of paclitaxel (PTX) nanoemulsions and hyaluronic acid (HA) to specifically target non-small cell lung cancer. HPNs were composed of dl-α-tocopheryl acetate, soybean oil, polysorbate 80, ferric chloride, and HA and fabricated by high-pressure homogenization. The HPNs were 85.2 ± 7.55 nm in diameter and had a zeta potential of −35.7 ± 0.25 mV. The encapsulation efficiency was almost 100%, and the PTX content was 3.0 mg/mL. We assessed the in vivo antitumor efficacy of the HPNs by measuring changes in tumor volume and body weight in nude mice transplanted with CD44-overexpressing NCI-H460 xenografts and treated with a bolus dose of saline, Taxol^®, PTX nanoemulsions (PNs), or HPNs at a dose of 25 mg/kg. Suppression of cancer cell growth was higher in the PN- and HPN-treated groups than in the Taxol^® group. In particular, HPN treatment dramatically inhibited tumor growth, likely because of the specific tumor-targeting affinity of HA for CD44-overexpressed cancer cells. The loss of body weight and organ weight did not vary significantly between the groups. It is suggest that HPNs should be used to effective nanocarrier system for targeting delivery of non-small cell lung cancer overexpressing CD44 and high solubilization of poorly soluble drug.

Microfluidic-assisted fabrication of carriers for controlled drug delivery

The microfluidic technique has brought unique opportunities toward the full control over the production processes for drug delivery carriers, owing to the miniaturisation of the fluidic environment. In comparison to the conventional batch methods, the microfluidic setup provides a range of advantages, including the improved controllability of material characteristics, as well as the precisely controlled release profiles of payloads. This review gives an overview of different fluidic principles used in the literature to produce either polymeric microparticles or nanoparticles, focusing on the materials that could have an impact on drug delivery. We also discuss the relations between the particle size and size distribution of the obtained carriers, and the design and configuration of the microfluidic setups. Overall, the use of microfluidic technologies brings exciting opportunities to expand the body of knowledge in the field of controlled drug delivery and great potential to clinical translation of drug delivery systems.

Sindbis Virus-Pseudotyped Lentiviral Vectors Carrying VEGFR2-Specific Nanobody for Potential Transductional Targeting of Tumor Vasculature

Introduction of selectivity/specificity into viral-based gene delivery systems, such as lentiviral vectors (LVs), is crucial in their systemic administration for cancer gene therapy. The pivotal role of tumor-associated endothelial cells (TAECs) in tumor angiogenesis and overexpression of vascular endothelial growth factor receptor-2 (VEGFR2 or KDR) in TAECs makes them a potent target in cancer treatment. Herein, we report the development of VEGFR2-targeted LVs pseudotyped with chimeric sindbis virus E2 glycoprotein (cSVE2s). For this purpose, either sequence of a VEGFR2-specific nanobody or its natural ligand (VEGF₁₂₁) was inserted into the binding site of sindbis virus E2 glycoprotein. In silico modeling data suggested that the inserted targeting motifs were exposed in the context of cSVE2s. Western blot analysis of LVs indicated the incorporation of cSVE2s into viral particles. Capture ELISA demonstrated the specificity/functionality of the incorporated cSVE2s. Transduction of 293/KDR (expressing VEGFR2) or 293T cells (negative control) by constructed LVs followed by fluorescent microscopy and flow cytometric analyses indicated selective transduction of 293/KDR cells (30 %) by both targeting motifs compared to 293T control cells (1-2 %). These results implied similar targeting properties of VEGFR2-specific nanobody compared to the VEGF₁₂₁ and indicated the potential for transductional targeting of tumor vasculature by the nanobody displaying LVs.

Paclitaxel-loaded hyaluronan solid nanoemulsions for enhanced treatment efficacy in ovarian cancer

Paclitaxel-loaded hyaluronan solid nanoemulsions (PTX-HSNs) were successfully fabricated for the delivery of PTX to improve ovarian cancer treatment via active tumor targeting. PTX-HSNs were fabricated using high-pressure homogenization with a microfluidizer and were lyophilized with d-mannitol. Hyaluronan was coated on the outside of the PTX-HSN sphere. The mean size of the PTX-HSNs was maintained less than 100 nm, with a relatively narrow size distribution. The PTX loading content was 3 mg/mL, and encapsulation efficiency (EE) was close to 100%. In vitro cell affinity studies using SK-OV-3 (cluster of differentiation 44 [CD44⁺]) and OVCAR-3 (CD44⁻) cells showed that PTX-HSN had a targeting capability hundredfold higher than that of PTX-loaded solid nanoemulsions (PTX-SNs) without hyaluronan. Further, the in vitro PTX release by PTX-SNs and PTX-HSNs lasted more than 6 days without showing a release burst, which was more sustained than that of Taxol^®, suggesting a more constant effect on cancer cells at the tumor site than was observed for Taxol. The in vivo toxicity, in vivo antitumor effects, and pharmacokinetics of PTX-HSNs and Taxol were evaluated in nude mice and rats. The maximum tolerated dose (MTD) for PTX-HSNs, PTX-SNs, and Taxol was determined by measuring changes in clinical symptoms after administering 20–50 mg/kg PTX via the caudal vein. The MTD of PTX-HSNs had a dosing capacity greater than 50 mg PTX/kg, which was 2.5-fold higher than that of Taxol when administered as a PTX injection. In vivo, PTX-HSN treatment effectively inhibited tumor growth and showed less toxicity in tumor-transplanted mice compared to that observed for Taxol treatments. The pharmacokinetic parameters of PTX-HSNs were more desirable than those of Taxol. After PTX-HSN treatment, the circulation time of PTX was prolonged and retention of PTX in ovarian tumor tissues increased. Therefore, PTX-HSN is a highly effective nanosystem with a high MTD for delivering PTX to ovarian cancers characterized by CD44 overexpression, enhanced active tumor targeting, and low toxicity.

Mechanistic Studies on the Self-Assembly of PLGA Patchy Particles and Their Potential Applications in Biomedical Imaging

Currently, several challenges prevent poly(lactic-co-glycolic acid) (PLGA) particles from reaching clinical settings. Among these is a lack of understanding of the molecular mechanisms involved in the formation of these particles. We have been studying in depth the formation of patchy polymeric particles. These particles are made of PLGA and lipid-polymer functional groups. They have unique patch-core-shell structural features: hollow or solid hydrophobic cores and a patchy surface. Previously, we identified the shear stress as the most important parameter in a patchy particle's formation. Here, we investigated in detail the role of shear stress in the patchy particle's internal and external structure using an integrative experimental and computational approach. By cross-sectioning the multipatch particles, we found lipid-based structures embedded in the entire PLGA matrix, which represents a unique finding in the PLGA field. By developing novel computational fluid dynamics and molecular dynamics simulations, we found that the shear stress determines the internal structure of the patchy particles. Equally important, we discovered that these particles emit a photoacoustic (PA) signal in the optical clinical imaging window. Our results show that particles with multiple patches emit a higher PA signal than single-patch particles. This phenomenon most likely is due to the fact that multipatchy particles absorb more heat than single-patchy particles as shown by differential scanning calorimetry analysis. Furthermore, we demonstrated the use of patchy polymeric particles as photoacoustic molecular probes both in vitro and in vivo studies. The fundamental studies described here will help us to design more effective PLGA carriers for a number of medical applications as well as to accelerate their medical translation.

Lipid-based nanosystems for CD44 targeting in cancer treatment: recent significant advances, ongoing challenges and unmet needs

Extensive experimental evidence demonstrates the important role of hyaluronic acid (HA)-CD44 interaction in cell proliferation and migration, inflammation and tumor growth. Taking advantage of this interaction, the design of HA-modified nanocarriers has been investigated for targeting CD44-overexpressing cells with the purpose of delivering drugs to cancer or inflammatory cells. The effect of such modification on targeting efficacy is influenced by several factors. In this review, we focus on the impact of HA-modification on the characteristics of lipid-based nanoparticles. We try to understand how these modifications influence particle physicochemical properties, interaction with CD44 receptors, intracellular trafficking pathways, toxicity, complement/macrophage activation and pharmacokinetics. Our aim is to provide insight in tailoring particle modification by HA in order to design more efficient CD44-targeting lipid nanocarriers.

Tumor vascular-targeted co-delivery of anti-angiogenesis and chemotherapeutic agents by mesoporous silica nanoparticle-based drug delivery system for synergetic therapy of tumor

To overcome the drawback of drug non-selectivity in traditional chemotherapy, the construction of multifunctional targeting drug delivery systems is one of the most effective and prevailing approaches. The intratumoral anti-angiogenesis and the tumor cell-killing are two basic approaches in fighting tumors. Herein we report a novel tumor vascular-targeting multidrug delivery system using mesoporous silica nanoparticles as carrier to co-load an antiangiogenic agent (combretastatin A4) and a chemotherapeutic drug (doxorubicin) and conjugate with targeting molecules (iRGD peptide) for combined anti-angiogenesis and chemotherapy. Such a dual-loaded drug delivery system is capable of delivering the two agents at tumor vasculature and then within tumors through a differentiated drug release strategy, which consequently results in greatly improved antitumor efficacy at a very low doxorubicin dose of 1.5 mg/kg. The fast release of the antiangiogenic agent at tumor vasculatures led to the disruption of vascular structure and had a synergetic effect with the chemotherapeutic drug slowly released in the following delivery of chemotherapeutic drug into tumors.

Preparation and cellular targeting study of VEGF-conjugated PLGA nanoparticles

Vascular endothelial growth factor receptor (VEGFR) is over-expressed on a variety of tumour cells and tumour neovasculature, and so becomes well-documented target for cancer treatment. This study was designed to evaluate the cellular targeting and anti-tumor potency of VEGF-conjugated nanoparticles (VEGF-NPs). The poly-lactic-co-glycolic acid nanoparticles were prepared using the emulsion-solvent evaporation method and the VEGF was conjugated on surface of nanoparticles by covalent coupling method. The obtained particles were found to be of spherical shape exhibiting a size of 710 nm and VEGF conjugation efficiency was 16.6%. The results in vitro test showed that VEGF-NPs were more associated to Human Umbilical Vein Endothelial Cells by binding to VEGFR. In vitro cell proliferation test, IC50 showed the superior antiproliferative activity of paclitaxel-loaded VEGF-NPs over unconjugated nanoparticles and native paclitaxel due to higher cellular association on tumour cells. So, the VEGF-NPs offer a promising active targeting carrier for tumour selective treatment.