Inhibition Against Growth of Glioblastoma Multiforme In Vitro Using Etoposide-Loaded Solid Lipid Nanoparticles with ρ-Aminophenyl-α-D-Manno-Pyranoside and Folic Acid

A comprehensive review on lipid nanocarrier systems for cancer treatment: fabrication, future prospects and clinical trials

Over the last few decades, cancer has been considered a clinical challenge, being among the leading causes of mortality all over the world. Although many treatment approaches have been developed for cancer, chemotherapy is still the most utilized in the clinical setting. However, the available chemotherapeutics-based treatments have several caveats including their lack of specificity, adverse effects as well as cancer relapse and metastasis which mainly explains the low survival rate of patients. Lipid nanoparticles (LNPs) have been utilized as promising nanocarrier systems for chemotherapeutics to overcome the challenges of the currently applied therapeutic strategies for cancer treatment. Loading chemotherapeutic agent(s) into LNPs improves drug delivery at different aspects including specific targeting of tumours, and enhancing the bioavailability of drugs at the tumour site through selective release of their payload, thus reducing their undesired side effects on healthy cells. This review article delineates an overview of the clinical challenges in many cancer treatments as well as depicts the role of LNPs in achieving optimal therapeutic outcomes. Moreover, the review contains a comprehensive description of the many LNPs categories used as nanocarriers in cancer treatment to date, as well as the potential of LNPs for future applications in other areas of medicine and research.

Lipid nanostructures for targeting brain cancer

Advancements in both material science and bionanotechnology are transforming the health care sector. To this end, nanoparticles are increasingly used to improve diagnosis, monitoring, and therapy. Huge research is being carried out to improve the design, efficiency, and performance of these nanoparticles. Nanoparticles are also considered as a major area of research and development to meet the essential requirements for use in nanomedicine where safety, compatibility, biodegradability, biodistribution, stability, and effectiveness are requirements towards the desired application. In this regard, lipids have been used in pharmaceuticals and medical formulations for a long time. The present work focuses on the use of lipid nanostructures to combat brain tumors. In addition, this review summarizes the literature pertaining to solid lipid nanoparticles (SLN) and nanostructured lipid carriers (LNC), methods of preparation and characterization, developments achieved to overcome blood brain barrier (BBB), and modifications used to increase their effectiveness.

Solid Lipid Nanoparticles (SLNs): An Advanced Drug Delivery System Targeting Brain through BBB

The blood-brain barrier (BBB) plays a vital role in the protection and maintenance of homeostasis in the brain. In this way, it is an interesting target as an interface for various types of drug delivery, specifically in the context of the treatment of several neuropathological conditions where the therapeutic agents cannot cross the BBB. Drug toxicity and on-target specificity are among some of the limitations associated with current neurotherapeutics. In recent years, advances in nanodrug delivery have enabled the carrier system containing the active therapeutic drug to target the signaling pathways and pathophysiology that are closely linked to central nervous system (CNS) disorders such as Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD), multiple sclerosis (MS), brain tumor, epilepsy, ischemic stroke, and neurodegeneration. At present, among the nano formulations, solid lipid nanoparticles (SLNs) have emerged as a putative drug carrier system that can deliver the active therapeutics (drug-loaded SLNs) across the BBB at the target site of the brain, offering a novel approach with controlled drug delivery, longer circulation time, target specificity, and higher efficacy, and more importantly, reducing toxicity in a biomimetic way. This paper highlights the synthesis and application of SLNs as a novel nontoxic formulation strategy to carry CNS drugs across the BBB to improve the use of therapeutics agents in treating major neurological disorders in future clinics.

Solid Lipid Nanoparticles and Nanostructured Lipid Carriers as Smart Drug Delivery Systems in the Treatment of Glioblastoma Multiforme

Glioblastoma multiforme (GBM) is the most common and malignant type of brain tumor. In fact, tumor recurrence usually appears a few months after surgical resection and chemotherapy, mainly due to many factors that make GBM treatment a real challenge, such as tumor location, heterogeneity, presence of the blood-brain barrier (BBB), and others. Solid lipid nanoparticles (SLNs) and nanostructured lipid carriers (NLCs) represent the most promising carriers for therapeutics delivery into the central nervous system (CNS) owing to their inherent ability to cross the BBB. In this review, we present the main challenges in GBM treatment, a description of SLNs and NLCs and their valuable role as drug carriers in GBM treatment, and finally, a detailed description of all modification strategies that aim to change composition of SLNs and NLCs to enhance treatment outcomes. This includes modification of SLNs and NLCs to improve crossing the BBB, reduced GBM cell resistance, target GBM cells selectively minimizing side effects, and modification strategies to enhance SLNs and NLCs nose-to-brain delivery. Finally, future perspectives on their use are also be discussed, to provide insight about all strategies with SLNs and NLCs formulation that could result in drug delivery systems for GBM treatment with highly effective theraputic and minimum undesirable effects.

Role of Nanomedicine in Treatment of Brain Cancer

Background:

Drug delivery to cancerous brain is a challenging task as it is surrounded by an efficient protective barrier. The main hurdles for delivery of bioactive molecules to cancerous brain are blood brain barrier (BBB), the invasive nature of gliomas, drug resistance, and difficult brain interstitium transportation. Therefore, treatment of brain cancer with the available drug regimen is difficult and has shown little improvement in recent years.

Methods:

We searched about recent advancements in the use of nanomedicine for effective treatment of the brain cancer. We focused on the use of liposomes, nanoparticles, polymeric micelles, and dendrimers to improve brain cancer therapy.

Results:

Nanomedicines are well suited for the treatment of brain cancer owing to their highly acceptable biological, chemical, and physical properties. Smaller size of nanomedicines also enhances their anticancer potential and penetration into blood brain barrier (BBB).

Conclusion:

Recently, nanomedicine based approaches have been developed and investigated for effective treatment of brain cancer. Some of these have been translated into clinical practice, in order to attain therapeutic needs of gliomas. Future advancements in nanomedicines will likely produce significant changes in methods and practice of brain cancer therapy.

Nose-to-brain delivery of antiglioblastoma drugs embedded into lipid nanocarrier systems: status quo and outlook

Glioblastoma multiforme (GBM) is one of the most devastating and deadly types of tumor. Among all the present treatment strategies, the utmost prerequisite is prolonged intervention at the malignant site. The blood-brain barrier (BBB) is the bottleneck in the delivery of anti-GBM drugs and invasive treatment comes with many pitfalls. This review will discuss the potential of embedding antitumor drugs into nanocarriers for intranasal delivery. Additionally, it emphasizes the significance of applying quality by design (QbD) methodology from the early development stages to ensure the high quality, safety and efficacy of the developed carrier system.

Targeted delivery of etoposide, carmustine and doxorubicin to human glioblastoma cells using methoxy poly(ethylene glycol)‑poly(ε‑caprolactone) nanoparticles conjugated with wheat germ agglutinin and folic acid

Wheat germ agglutinin (WGA) and folic acid (FA)-grafted methoxy poly(ethylene glycol) (MPEG)‑poly(ε‑caprolactone) (PCL) nanoparticles (WFNPs) were applied to transport anticancer drugs across the blood-brain barrier and treat glioblastoma multiforme (GBM). PCL was copolymerized with MPEG, and MPEG-PCL NPs were stabilized with pluronic F127 using a microemulsion-solvent evaporation technique and crosslinked with WGA and FA. The targeting ability of WFNPs loaded with etoposide (ETO), carmustine (BCNU) and doxorubicin (DOX) was investigated via the binding affinity of drug-loaded NP formulations to N‑acetylglucosamine expressed in human brain microvascular endothelial cells and to folate receptor in malignant U87MG cells. We found that a shorter PCL chain in drug-loaded MPEG-PCL NPs yielded a smaller average size of the particles. An increase in PCL chain length (stronger hydrophobicity) enhanced drug entrapment efficiencies in MPEG-PCL NPs, and reduced drug-releasing rates from NP formulations. In addition, anti-proliferative activity against U87MG cells for the 3 drugs followed the order of WFNPs > FA-grafted NPs > WGA-grafted NPs > MPEG-PCL NPs. Immunofluorescence staining revealed that the ligands of drug-loaded WFNPs connected to N‑acetylglucosamine and folate receptor with the help of surface WGA and FA. WFNPs carrying ETO, BCNU and DOX acted as dual-targeting nanocarriers, and their use can be a promising approach to inhibiting GBM growth in the brain.

Targeted Theranostic Nanoparticles for Brain Tumor Treatment

The poor prognosis and rapid recurrence of glioblastoma (GB) are associated to its fast-growing process and invasive nature, which make difficult the complete removal of the cancer infiltrated tissues. Additionally, GB heterogeneity within and between patients demands a patient-focused method of treatment. Thus, the implementation of nanotechnology is an attractive approach considering all anatomic issues of GB, since it will potentially improve brain drug distribution, due to the interaction between the blood⁻brain barrier and nanoparticles (NPs). In recent years, theranostic techniques have also been proposed and regarded as promising. NPs are advantageous for this application, due to their respective size, easy surface modification and versatility to integrate multiple functional components in one system. The design of nanoparticles focused on therapeutic and diagnostic applications has increased exponentially for the treatment of cancer. This dual approach helps to understand the location of the tumor tissue, the biodistribution of nanoparticles, the progress and efficacy of the treatment, and is highly useful for personalized medicine-based therapeutic interventions. To improve theranostic approaches, different active strategies can be used to modulate the surface of the nanotheranostic particle, including surface markers, proteins, drugs or genes, and take advantage of the characteristics of the microenvironment using stimuli responsive triggers. This review focuses on the different strategies to improve the GB treatment, describing some cell surface markers and their ligands, and reports some strategies, and their efficacy, used in the current research.

Advances in the design of solid lipid nanoparticles and nanostructured lipid carriers for targeting brain diseases

Solid lipid nanoparticles (SLNs) and nanostructured lipid carriers (NLCs) comprise a category of versatile drug delivery systems that have been used in the biomedical field for >25years. SLNs and NLCs have been used for the treatment of various diseases including cardiovascular and cerebrovascular, and are considered a standard treatment for the latter, due to their inherent ability to cross the blood brain barrier (BBB). In this review, a presentation of the most important brain diseases (brain cancer, ischemic stroke, Alzheimer's disease, Parkinson's disease and multiple sclerosis) is approached, followed by the basic fabrication techniques of SLNs and NLCs. A detailed description of the reported studies of the last seven years, of active and passive targeting SLNs and NLCs for the treatment of glioblastoma multiforme and of other brain cancers, as well as for the treatment of neurodegenerative diseases is also carried out. Finally, a brief description of the advantages, the disadvantages, and the future perspectives in the use of these nanocarriers is reported, aiming at giving an insight of the limitations that have to be overcome in order to result in a delivery system with high therapeutic efficacy and without the limitations of the existing nano-systems.

Translational gap in ongoing clinical trials for glioma

Despite the vast amounts of information gathered about gliomas, the overall survival of glioma patients has not improved in the last four decades. This could partially be due to an apparent failure to include basic concepts of glioma biology into clinical trials. Specifically, attempts to overcome the limitations of the blood brain barrier (BBB) and the chemoresistance of glioma stem cells (GSCs) were seldom included (a phenomenon known as the translational gap, TG) in a study involving 29 Phase I/II clinical trials (P2CT) published in 2011. The aim of this study was to re-evaluate this finding with a new series of 100 ongoing, but still unpublished, P2CT in order to determine if there is a TG reduction. As indicators, we evaluated in each P2CT the number of drugs tested, concomitant radiotherapy, and the ability of drugs to pass the BBB and to target GSCs. Compared to clinical trials published in 2011, we found that while in OCT there is an increase in the number of P2CT using two drugs (from 24.1% to 44.9%), and an increase in the number of drugs able to pass the BBB (7.14% versus 64.29%) and target GSCs (0% versus 16.3%), there was a decrease in the number of P2CT using concomitant radiotherapy (34.5% versus 18.37%). Overall our results suggest that there is only a modest improvement regarding reducing the TG because the vast majority of ongoing P2CT are still not including well known concepts of glioma biology important for a successful treatment.

Nanotechnology in Glycomics: Applications in Diagnostics, Therapy, Imaging, and Separation Processes

This review comprehensively covers the most recent achievements (from 2013) in the successful integration of nanomaterials in the field of glycomics. The first part of the paper addresses the beneficial properties of nanomaterials for the construction of biosensors, bioanalytical devices, and protocols for the detection of various analytes, including viruses and whole cells, together with their key characteristics. The second part of the review focuses on the application of nanomaterials integrated with glycans for various biomedical applications, that is, vaccines against viral and bacterial infections and cancer cells, as therapeutic agents, for in vivo imaging and nuclear magnetic resonance imaging, and for selective drug delivery. The final part of the review describes various ways in which glycan enrichment can be effectively done using nanomaterials, molecularly imprinted polymers with polymer thickness controlled at the nanoscale, with a subsequent analysis of glycans by mass spectrometry. A short section describing an active glycoprofiling by microengines (microrockets) is covered as well.

Co-delivery of etoposide and curcumin by lipid nanoparticulate drug delivery system for the treatment of gastric tumors

CONTEXT

Gastric carcinoma (GC) is one of the most common cancers and the second most frequent cause of cancer-related deaths. Chemotherapy is an important therapeutic modality for GC. However, chemoresistance limited its success rate. Combination chemotherapy is often applied to prevent drug-induced resistance in cancers.

OBJECTIVE

The aim of this study is to evaluate whether the co-delivery of etoposide (ETP) and curcumin (CUR) with one nanoparticle can result in synergistic effects of both drugs.

METHODS

ETP- and CUR-loaded nanostructured lipid carriers (ETP-CUR-NLC) were prepared by the solvent injection technique. Their average size, zeta potential and drug loading were evaluated. Human gastric cancer cell lines (SGC7901 cells) were used for the testing of in vitro cytotoxicity studies, and in vivo anti-tumor efficacies of the carriers were evaluated on mice bearing SGC7901 cells xenografts.

RESULTS

ETP-CUR-NLC has a particle size of 114 nm, EPT-loading quantity of 83% and CUR-loading quantity of 82%. ETP-CUR-NLC displayed high cytotoxicity and enhanced antitumor activity in vitro and in vivo. Meanwhile, ETP-CUR-NLC displayed low cytotoxicity in normal tissues in vivo.

DISCUSSION AND CONCLUSION

The results demonstrate that ETP-CUR-NLC can achieve impressive anti-tumor activity. By combining CUR, an effective NF-κB inhibitor, with ETP, a powerful anticancer drug, in NLC, we could improve the therapeutic efficacy in cancer treatments. Our results showed that such co-loaded delivery systems could serve as a promising therapeutic approach to improve clinical outcomes against various malignancies.

CS/PAA@TPGS/PLGA nanoparticles with intracellular pH-sensitive sequential release for delivering drug to the nucleus of MDR cells

Development of novel nano-drug delivery systems (NDDS) that can transport anticancer drugs into cell nuclei is still a highly desirable strategy for reversing multi-drug resistance (MDR) in cancer therapy. Herein, we designed and prepared a novel NDDS, designated S@L NPs, in which several smaller nanoparticles are contained within a larger nanoparticle. Our S@L NPs (CS/PAA/VP-16@TPGS/PLGA NPs) possess a structure in which smaller nanoparticles (Chitosan-Poly(acrylic acid) nanoparticles, CS/PAA NPs) containing the drug etoposide (VP-16) are loaded within a larger nanoparticle (Vitamin E d-a-tocopheryl polyethylene glycol 1000 succinate-modified poly(lactic-co-glycolic acid) nanoparticles, TPGS/PLGA NPs). The system utilizes intracellular pH gradients to achieve pH-sensitive sequential release within different intracellular domains of MDR cells. S@L NPs could be triggered to degrade and release CS/PAA/VP-16 NPs in the acid environment of the cytosol, endosomes or lysosomes, and CS/PAA/VP-16 NPs were capable of entering the nucleus through nucleopores. It is significant that CS/PAA/VP-16 NPs exhibit disaggregation in the alkaline environment of the nucleus and thereby release the contained anticancer drug. Further mechanistic studies showed that CS/PAA/VP-16 NPs escaped retention and degradation within lysosomes and protected the drug from P-glycoprotein-induced efflux. Simultaneously, S@L NPs enhanced the anticancer effect of the loaded drug by inducing autophagy and apoptosis of MDR cells. This novel NDDS may provide a promising platform for nuclear drug delivery for reversing MDR.

Effective tumor-targeted delivery of etoposide using chitosan nanoparticles conjugated with folic acid and sulfobetaine methacrylate

FA–CS(VP-16)-g-PSBMA nanoparticles were synthesized and showed effective tumor-targeting properties and promising anti-tumor capacity in vivo.

Conjugation of melanotransferrin antibody on solid lipid nanoparticles for mediating brain cancer malignancy

Solid lipid nanoparticles (SLNs) comprising complex internal lipids were conjugated with melanotransferrin antibody (MA) to carry anticancer etoposide across the blood-brain barrier (BBB) for managing glioblastoma multiforme (GBM). MA was crosslinked on the surface of etoposide-loaded SLNs (ETP-SLNs) to target human brain-microvascular endothelial cells (HBMECs) and U87MG cells. The experimental evidences showed that an increase in the tripalmitin weight percentage in lipids enhanced the particle size and viability of U87MG cells, however decreased the etoposide loading efficiency, MA conjugation efficiency, and permeability coefficient for etoposide across the BBB. A high level of MA on the particle surface increased the atomic ratio of nitrogen to phosphorus and permeability coefficient for propidium iodide and etoposide across the BBB, however reduced the MA conjugation efficiency, transendothelial electrical resistance, and viability of U87MG cells. Based on immunochemical staining, we found that MA on ETP-SLNs triggered the melanotransferrin-mediated transcytosis and promoted the growth-inhibitory efficacy to U87MG cells. MA-conjugated ETP-SLNs can be a promising colloidal delivery system for malignant GBM pharmacotherapy. © 2015 American Institute of Chemical Engineers Biotechnol. Prog., 32:480-490, 2016.

Brain targeted delivery of carmustine using solid lipid nanoparticles modified with tamoxifen and lactoferrin for antitumor proliferation

Solid lipid nanoparticles (SLNs) conjugated with tamoxifen (TX) and lactoferrin (Lf) were applied to carry anticancer carmustine (BCNU) across the blood-brain barrier (BBB) for enhanced antiproliferation against glioblastoma multiforme (GBM). BCNU-loaded SLNs with modified TX and Lf (TX-Lf-BCNU-SLNs) were used to penetrate a monolayer of human brain-microvascular endothelial cells (HBMECs) and human astrocytes and to target malignant U87MG cells. The surface TX and Lf on TX-Lf-BCNU-SLNs improved the characteristics of sustained release for BCNU. When compared with BCNU-loaded SLNs, TX-Lf-BCNU-SLNs increased the BBB permeability coefficient for BCNU about ten times. In addition, TX-BCNU-SLNs considerably promoted the fluorescent intensity of intracellular acetomethoxy derivative of calcein (calcein-AM) in HBMECs via endocytosis. However, the conjugated Lf could only slightly increase the fluorescence of calcein-AM. Moreover, the order of formulation in the inhibition to U87MG cells was TX-Lf-BCNU-SLNs>TX-BCNU-SLNs>Lf-BCNU-SLNs>BCNU-SLNs. TX-Lf-BCNU-SLNs can be effective in infiltrating the BBB and delivering BCNU to GBM for future chemotherapy application.