Therapeutic nanomedicine for brain cancer

A recent insight of applications of gold nanoparticles in glioblastoma multiforme therapy

The application of gold nanoparticles (AuNPs) in cancer therapy, particularly targeted therapy of glioblastoma multiforme (GBM), is an up-and-coming field of research that has gained much interest in recent years. GBM is a life-threatening malignant tumour of the brain that currently has a 95 % death rate with an average of 15 months of survival. AuNPs have proven to have wide clinical implications and compelling therapeutic potential in many researches, specifically in GBM treatment. It was found that the reason why AuNPs were highly desired for GBM treatment was due to their unique properties that diversified the applications of AuNPs further to include imaging, diagnosis, and photothermal therapy. These properties include easy synthesis, biocompatibility, and surface functionalization. Various studies also underscored the ability of AuNPs to cross the blood-brain-barrier and selectively target tumour cells while displaying no major safety concerns which resulted in better therapy results. We attempt to bring together some of these studies in this review and provide a comprehensive overview of safety evaluations and current and potential applications of AuNPs in GBM therapy that may result in AuNP-mediated therapy to be the new gold standard for GBM treatment.

New insights into targeted therapy of glioblastoma using smart nanoparticles

In recent times, the intersection of nanotechnology and biomedical research has given rise to nanobiomedicine, a captivating realm that holds immense promise for revolutionizing diagnostic and therapeutic approaches in the field of cancer. This innovative fusion of biology, medicine, and nanotechnology aims to create diagnostic and therapeutic agents with enhanced safety and efficacy, particularly in the realm of theranostics for various malignancies. Diverse inorganic, organic, and hybrid organic-inorganic nanoparticles, each possessing unique properties, have been introduced into this domain. This review seeks to highlight the latest strides in targeted glioblastoma therapy by focusing on the application of inorganic smart nanoparticles. Beyond exploring the general role of nanotechnology in medical applications, this review delves into groundbreaking strategies for glioblastoma treatment, showcasing the potential of smart nanoparticles through in vitro studies, in vivo investigations, and ongoing clinical trials.

Transferrin functionalized poloxamer-chitosan nanoparticles of metformin: physicochemical characterization, in-vitro, and Ex-vivo studies

OBJECT

We report the preparation, characterization, and in-vitro therapeutic evaluation of Metformin-Loaded, Transferrin-Poloxamer-Functionalized Chitosan Nanoparticles (TPMC-NPs) for their repurposing in Alzheimer's disease (AD).

SIGNIFICANCE

Usefulness of this work to establish the repurposing of metformin for the treatment of AD.

METHODS

The TPMC-NPs were prepared by ionic gelation method using sodium tripolyphosphate. The modification and functionalization were confirmed by FTIR and 1H-NMR spectroscopy. The physicochemical characterization was performed using DLS, FTIR,1H-NMR, CD spectroscopy, SEM, DSC, PXRD, HR-TEM, and hot-stage microscopy.

RESULTS

The size, PDI, percent entrapment efficiency, and percent drug loading of TPMC-NPs were found to be 287.4 ± 9.5, 0.273 ± 0.067, 81.15 ± 7.17%, 11.75%±8.21%, respectively. Electron microscope analysis revealed smooth and spherical morphology. The transferrin conjugation efficiency was found to be 46% by the BCA method. CD spectroscopy confirmed no significant loss of the secondary structure of transferrin after conjugation. PXRD data indicated the amorphous nature of the TPMC-NPs. Hot-stage microscopy and DSC confirmed the thermal stability of TPMC-NPs. The in-vitro drug release showed a sustained release at pH 7.4. The DPPH assay displayed 80% antioxidant activity of TPMC-NPs in comparison with metformin and blank NPs. The in-vitro cytotoxicity assay revealed 69.60% viable SH- SY5Y cells at 100 µg/mL of TPMC NPs. The ex-vivo nasal ciliotoxicity and mucoadhesion studies showed no significant toxicity, and 98.16% adhesion, respectively. The nasal permeability study showed the release of metformin within 30 min from TPMC-NPs.

CONCLUSION

The obtained results suggested the usefulness of TPMC-NPs in the treatment of AD via the intranasal route.

Recent Advancements in Nanomaterials: A Promising Way to Manage Neurodegenerative Disorders

Neurodegenerative diseases (NDs) such as dementia, Alzheimer's disease, Parkinson's disease, frontotemporal dementia, and amyotrophic lateral sclerosis are some of the most prevalent disorders currently afflicting healthcare systems. Many of these diseases share similar pathological hallmarks, including elevated oxidative stress, mitochondrial dysfunction, protein misfolding, excitotoxicity, and neuroinflammation, all of which contribute to the deterioration of the nervous system's structure and function. The development of diagnostic and therapeutic materials in the monitoring and treatment of these diseases remains challenging. One of the biggest challenges facing therapeutic and diagnostic materials is the blood-brain barrier (BBB). The BBB is a multifunctional membrane possessing a plethora of biochemical, cellular, and immunological features that ensure brain homeostasis by preventing the entry and accumulation of unwanted compounds. With regards to neurodegenerative diseases, the recent application of tailored nanomaterials (nanocarriers and nanoparticles) has led to advances in diagnostics and therapeutics. In this review, we provide an overview of commonly used nanoparticles and their applications in NDs, which may offer new therapeutic strategies for the prevention and treatment of neurodegenerative diseases.

Mechanisms of Resistance and Current Treatment Options for Glioblastoma Multiforme (GBM)

Glioblastoma multiforme (GBM) is a highly aggressive form of brain cancer that is difficult to treat due to its resistance to both radiation and chemotherapy. This resistance is largely due to the unique biology of GBM cells, which can evade the effects of conventional treatments through mechanisms such as increased resistance to cell death and rapid regeneration of cancerous cells. Additionally, the blood–brain barrier makes it difficult for chemotherapy drugs to reach GBM cells, leading to reduced effectiveness. Despite these challenges, there are several treatment options available for GBM. The standard of care for newly diagnosed GBM patients involves surgical resection followed by concurrent chemoradiotherapy and adjuvant chemotherapy. Emerging treatments include immunotherapy, such as checkpoint inhibitors, and targeted therapies, such as bevacizumab, that attempt to attack specific vulnerabilities in GBM cells. Another promising approach is the use of tumor-treating fields, a type of electric field therapy that has been shown to slow the growth of GBM cells. Clinical trials are ongoing to evaluate the safety and efficacy of these and other innovative treatments for GBM, intending to improve with outcomes for patients.

Update on the current knowledge of lymphatic drainage system and its emerging roles in glioma management

The draining of brain interstitial fluid (ISF) to cerebrospinal fluid (CSF) and the subsequent draining of CSF to meningeal lymphatics is well-known. Nonetheless, its role in the development of glioma is a remarkable finding that has to be extensively understood. The glymphatic system (GS) collects CSF from the subarachnoid space and brain ISF through aquaporin-4 (AQP4) water channels. The glial limiting membrane and the perivascular astrocyte-end-feet membrane both have elevated levels of AQP4. CSF is thought to drain through the nerve sheaths of the olfactory and other cranial nerves as well as spinal meningeal lymphatics via dorsal or basal lymphatic vessels. Meningeal lymphatic vessels (MLVs) exist below the skull in the dorsal and basal regions. In this view, MLVs offer a pathway to drain macromolecules and traffic immunological cells from the CNS into cervical lymph nodes (CLNs), and thus can be used as a candidate curing strategy against glioma and other associated complications, such as neuro-inflammation. Taken together, the lymphatic drainage system could provide a route or approach for drug targeting of glioma and other neurological conditions. Nevertheless, its pathophysiological role in glioma remains elusive, which needs extensive research. The current review aims to explore the lymphatic drainage system, its role in glioma progression, and possible therapeutic techniques that target MLVs in the CNS.

Nano-inspired smart medicines targeting brain cancer: diagnosis and treatment

Cancer, despite being the bull's eye for the research community, accounts for a large number of morbidity and mortality. Cancer of the brain is considered the most intractable, with the least diagnosis rates, hence treatment and survival. Despite the extensive development of therapeutic molecules, their targeting to the diseased site is a challenge. Specially tailored nanoparticles can efficiently deliver drugs and genes to the brain to treat tumours and diseases. These nanotechnology-based strategies target the blood-brain barrier, the local space, or a specific cell type. These nanoparticles are preferred over other forms of targeted drug delivery due to the chances for controlled delivery of therapeutic cargo to the intended receptor. Targeted cancer therapy involves using specific receptor-blocking compounds that block the spreading or growth of cancerous cells. This review presents an account of the recent applications of nano-based cancer theragnostic, which deal in conjunct functionalities of nanoparticles for effective diagnosis and treatment of cancer. It commences with an introduction to tumours of the brain and their grades, followed by hurdles in its conventional diagnosis and treatment. The characteristic mechanism of nanoparticles for efficiently tracing brain tumour grade and delivery of therapeutic genes or drugs has been summarised. Nanocarriers like liposomes have been widely used and commercialized for human brain cancer treatment. However, nano-inspired structures await their translational recognition. The green synthesis of nanomaterials and their advantages have been discussed. The article highlights the challenges in the nano-modulation of brain cancer and its future outlook.

Nanostructured lipid carriers: a promising drug carrier for targeting brain tumours

Background

In recent years, the field of nanotechnology and nanomedicine has transformed the pharmaceutical industry with the development of novel drug delivery systems that overcome the shortcomings of traditional drug delivery systems. Nanostructured lipid carriers (NLCs), also known as the second-generation lipid nanocarriers, are one such efficient and targeted drug delivery system that has gained immense attention all across due to their myriad advantages and applications. Scientific advancements have revolutionized our health system, but still, brain diseases like brain tumour have remained formidable owing to poor prognosis and the challenging drug delivery to the brain tissue. In this review, we highlighted the application and potential of NLCs in brain-specific delivery of chemotherapeutic agents.

Main body

NLCs are lipid-based formulations with a solid matrix at room temperature and offer advantages like enhanced stability, low toxicity, increased shelf life, improved drug loading capacity, and biocompatibility over other conventional lipid-based nanocarriers such as nanoemulsions and solid lipid nanoparticles. This review meticulously articulates the structure, classification, components, and various methods of preparation exemplified with various research studies along with their advantages and disadvantages. The concept of drug loading and release has been discussed followed by a brief about stability and strategies to improve stability of NLCs. The review also summarizes various in vitro and in vivo research studies on NLCs encapsulated with cytotoxic drugs and their potential application in brain-specific drug delivery.

Conclusion

NLCs are employed as an important carrier for the delivery of food, cosmetics, and medicines and recently have been used in brain targeting, cancer, and gene therapy. However, in this review, the applications and importance of NLCs in targeting brain tumour have been discussed in detail stating examples of various research studies conducted in recent years. In addition, to shed light on the promising role of NLCs, the current clinical status of NLCs has also been summarized.

Graphical Abstract

Targeting neuroinflammation by intranasal delivery of nanoparticles in neurological diseases: a comprehensive review

Neuroinflammation (NIF) plays an essential role in the pathology of neurological disorders like Parkinson's disease, Alzheimer's disease, multiple sclerosis, and epilepsy. Despite progress in the drug discovery and development of new drugs, drug delivery to the central nervous system (CNS) still represents the challenge due to the presence of the blood-brain barrier (BBB). Targeting NIF may require an adequate amount of drug to cross the BBB. Recently, the intranasal (IN) drug administration has attracted increasing attention as a reliable method to cross the BBB and treat neurological disorders. On the other hand, using optimized nanoparticles may improve the IN delivery limitations, increase the mucoadhesive properties, and prevent drug degradation. NPs can carry and deliver drugs to the CNS by bypassing the BBB. In this review, we described briefly the NIF as a pathologic feature of CNS diseases. The potential treatment possibilities with IN transfer of NP-loaded drugs will enhance the establishment of more efficient nanoformulations and delivery systems.

Recent developments in drug delivery strategies for targeting DNA damage response in glioblastoma

Glioblastoma is the most frequent and malignant brain tumor. The median survival for this disease is approximately 15 months, and despite all the available treatment strategies employed, it remains an incurable disease. Preclinical and clinical research have shown that the resistance process related to DNA damage repair pathways, glioma stem cells, blood-brain barrier selectivity, and dose-limiting toxicity of systemic treatment leads to poor clinical outcomes. In this context, the advent of drug delivery systems associated with localized treatment seems to be a promising and versatile alternative to overcome the failure of the current treatment approaches. In order to bypass therapeutic tumor resistance mechanisms, more effective combinatorial therapies should be identified, such as the use of cytotoxic drugs combined with the inhibition of DNA damage response (DDR)-related targets. Additionally, critical reasoning about the delivery approach and administration route in brain tumors treatment innovation is essential. The outcomes of future experimental studies regarding the association of delivery systems, alternative treatment routes, and DDR targets are expected to lead to the development of refined therapeutic interventions. Novel therapeutic approaches could improve the life's quality of glioblastoma patients and increase their survival rate.

Carbon Dots: An Innovative Tool for Drug Delivery in Brain Tumors

Brain tumors are particularly aggressive and represent a significant cause of morbidity and mortality in adults and children, affecting the global population and being responsible for 2.6% of all cancer deaths (as well as 30% of those in children and 20% in young adults). The blood-brain barrier (BBB) excludes almost 100% of the drugs targeting brain neoplasms, representing one of the most significant challenges to current brain cancer therapy. In the last decades, carbon dots have increasingly played the role of drug delivery systems with theranostic applications against cancer, thanks to their bright photoluminescence, solubility in bodily fluids, chemical stability, and biocompatibility. After a summary outlining brain tumors and the current drug delivery strategies devised in their therapeutic management, this review explores the most recent literature about the advances and open challenges in the employment of carbon dots as both diagnostic and therapeutic agents in the treatment of brain cancers, together with the strategies devised to allow them to cross the BBB effectively.

Nanobiotechnology-assisted therapies to manage brain cancer in personalized manner

There are numerous investigated factors that limit brain cancer treatment efficacy such as ability of prescribed therapy to cross the blood-brain barrier (BBB), tumor specific delivery of a therapeutics, transport within brain interstitium, and resistance of tumor cells against therapies. Recent breakthroughs in the field of nano-biotechnology associated with developing multifunctional nano-theranostic emerged as an effective way to manage brain cancer in terms of higher efficacy and least possible adverse effects. Keeping challenges and state-of-art accomplishments into consideration, this review proposes a comprehensive, careful, and critical discussion focused on efficient nano-enabled platforms including nanocarriers for drug delivery across the BBB and nano-assisted therapies (e.g., nano-immunotherapy, nano-stem cell therapy, and nano-gene therapy) investigated for brain cancer treatment. Besides therapeutic efficacy point-of-view, efforts are being made to explore ways projected to tune such developed nano-therapeutic for treating patients in personalized manner via controlling size, drug loading, delivery, and retention. Personalized brain tumor management based on advanced nano-therapies can potentially lead to excellent therapeutic benefits based on unique genetic signatures in patients and their individual disease profile. Moreover, applicability of nano-systems as stimulants to manage the brain cancer growth factors has also been discussed in photodynamic therapy and radiotherapy. Overall, this review offers a comprehensive information on emerging opportunities in nanotechnology for advancing the brain cancer treatment.

Biomimetic and cell-based nanocarriers - New strategies for brain tumor targeting

In the last two decades no significant advances were achieved in the treatment of the most frequent and malignant types of brain tumors. The main difficulties in achieving progress are related to the incapacity to deliver drugs in therapeutic amounts into the central nervous system and the associated severe side effects. Indeed, to obtain effective treatments, the drugs should be able to cross the intended biological barriers and not being inactivated before reaching the specific therapeutic target. To overcome these challenges the development of synthetic nanocarriers has been widely explored for brain tumor treatment but unfortunately with no clinical translation until date. The use of cell-derived nanocarriers or biomimetic nanocarriers has been studied in the last few years, considering their innate bio-interfacing properties. The ability to carry therapeutic agents and a higher selectivity towards brain tumors would bring new hope for the development of safe and effective treatments. In this review, we explore the biological barriers that need to be crossed for effective delivery in brain tumors, and the types and properties of cell-based nanocarriers (extracellular vesicles and cell-membrane coated nanocarriers) currently under investigation.

Highlights in targeted nanoparticles as a delivery strategy for glioma treatment

Glioma is the most common type of Central Nervous System (CNS) neoplasia and it arises from glial cells. As glial cells are formed by different types of cells, glioma can be classified according to the cells that originate it or the malignancy grade. Glioblastoma multiforme is the most common and aggressive glioma. The high lethality of this tumor is related to the difficulty in performing surgical removal, chemotherapy, and radiotherapy in the CNS. To improve glioma treatment, a wide range of chemotherapeutics have been encapsulated in nanosystems to increase their ability to overcome the blood-brain barrier (BBB) and specifically reach the tumoral cells, reducing side effects and improving drug concentration in the tumor microenvironment. Several studies have investigated nanosystems covered with targeting ligands (e.g., proteins, peptides, aptamers, folate, and glucose) to increase the ability of drugs to cross the BBB and enhance their specificity to glioma through specific recognition by receptors on BBB and glioma cells. This review addresses the main targeting ligands used in nanosystems to overcome the BBB and promote the active targeting of drugs for glioma. Furthermore, the advantages of using these molecules in glioma treatment are discussed.

Current Status of Brain Tumor in the Kingdom of Saudi Arabia and Application of Nanobiotechnology for Its Treatment: A Comprehensive Review

OBJECTIVE

Brain tumors are the most challenging of all tumors and accounts for about 3% of all cancer allied deaths. The aim of the present review is to examine the brain tumor prevalence and treatment modalities available in the Kingdom of Saudi Arabia. It also provides a comprehensive analysis of the application of various nanotechnology-based products for brain cancer treatments along with their prospective future advancements.

METHODS

A literature review was performed to identify and summarize the current status of brain cancer in Saudi Arabia and the scope of nanobiotechnology in its treatment.

RESULTS

Depending upon the study population data analysis, gliomas, astrocytoma, meningioma, and metastatic cancer have a higher incidence rate in Saudi Arabia than in other countries, and are mostly treated in accordance with conventional treatment modalities for brain cancer. Due to the poor prognosis of cancer, it has an average survival rate of 2 years. Conventional therapy includes surgery, radiotherapy, chemotherapy, and a combination thereof, but these do not control the disease's recurrence. Among the various nanomaterials discussed, liposomes and polymeric nanoformulations have demonstrated encouraging outcomes for facilitated brain cancer treatment.

CONCLUSIONS

Nanomaterials possess the capacity to overcome the shortcomings of conventional therapies. Polymer-based nanomaterials have shown encouraging outcomes against brain cancer when amalgamated with other nano-based therapies. Nonetheless, nanomaterials could be devised that possess minimal toxicity towards normal cells or that specifically target tumor cells. In addition, rigorous clinical investigations are warranted to prepare them as an efficient and safe modality for brain cancer therapy.

Recent Advances in Improved Anticancer Efficacies of Camptothecin Nano-Formulations: A Systematic Review

Camptothecin (CPT), a natural plant alkaloid, has indicated potent antitumor activities via targeting intracellular topoisomerase I. The promise that CPT holds in therapies is restricted through factors that include lactone ring instability and water insolubility, which limits the drug oral solubility and bioavailability in blood plasma. Novel strategies involving CPT pharmacological and low doses combined with nanoparticles have indicated potent anticancer activity in vitro and in vivo. This systematic review aims to provide a comprehensive and critical evaluation of the anticancer ability of nano-CPT in various cancers as a novel and more efficient natural compound for drug development. Studies were identified through systematic searches of PubMed, Scopus, and ScienceDirect. Eligibility checks were performed based on predefined selection criteria. Eighty-two papers were included in this systematic review. There was strong evidence for the association between antitumor activity and CPT treatment. Furthermore, studies indicated that CPT nano-formulations have higher antitumor activity in comparison to free CPT, which results in enhanced efficacy for cancer treatment. The results of our study indicate that CPT nano-formulations are a potent candidate for cancer treatment and may provide further support for the clinical application of natural antitumor agents with passive targeting of tumors in the future.

Therapeutic potential of Allium Sativum against the Aβ(1-40)-induced oxidative stress and mitochondrial dysfunction in the Wistar rats

From the early stages of any neurodegenerative-disease mitochondrial functionality has been mortally extricated, though the exact timeline of these events is still unclear, it is likely to represent a progressive neurons-decline and cognitive-functions. Hence strategies suggested by herbal extract to restore mitochondrial functions may be a remedial approach to chronic neurodegenerative disorder like Alzheimer's disease (AD). This research was designed to evaluate if Aβ1-40 induced oxidative stress and mitochondrial dysfunction could be inhibited by Allium Sativum (AS) supplementation. AD was induced by a single intra-hippocampal injection of Aβ1-40 (5 μg/4 μl), while herbal supplementation was given orally (100, 250, 500 mg/kg body weight, daily) for 3 weeks. Morris water maze was used to assess cognitive function shows deficits in Aβ1-40 treated animals, there is no significant alteration in locomotor function as examined by actophotometer. This was accompanied by enhancement in oxidative stress indicating by accentuated ROS and protein carbonyl levels. Concomitantly, decrease in activity of antioxidant enzymes was observed in diseased animals; as expressed by reduced superoxide-dismutase and catalase activity, as well as reduction in GSH levels and impaired mitochondrial functions. Medium dose of AS has been found effective in restoring the memory impairment along with antioxidant levels but high dose is more efficient as observed in the Aβ1-40 treated rats. High dose of AS, on the other hand significantly ameliorates the mitochondrial-dysfunction in comparison to medium dose. Taken together, the findings reveal that AS reverses Aβ1-40 induced brain alteration, it could be an efficient clinical mitigation action against AD growth.

Evidence of protein coronas around soft nanoparticles regardless of the chemical nature of the outer surface: structural features and biological consequences

The formation of biomolecular coronas around nanoparticles as soon as they come in contact with biological media is nowadays well accepted. The self-developed biological outer surfaces can affect the targeting capability of the colloidal carriers as well as their cytotoxicity and cellular uptake behavior. In this framework, we explored the structural features and biological consequences of protein coronas around block copolymer assemblies consisting of a common pH-responsive core made by poly[2-(diisopropylamino) ethyl methacrylate] (PDPA) and hydrophilic shells of different chemical natures: zwitterionic poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC) or highly hydrophilic poly(ethylene oxide) (PEO) and poly(N-(2-hydroxypropyl)methacrylamide) (PHPMA). We demonstrated the presence of ∼50 nm protein coronas around the nanoparticles regardless of the chemical nature of the polymeric shells. The thickness is understood as the sum of the soft and hard layers and it is the actual interface seen by the cells. Although the soft corona composition is difficult to determine because the proteins are loosely bound to the outer surface of the assemblies, the tightly bound proteins (hard corona) could be identified and quantified. The compositional analysis of the hard corona demonstrated that human serum albumin (HSA), immunoglobulin G (IgG) and fibrinogen are the main components of the protein coronas, and serotransferrin is present particularly in the protein corona of the zwitterionic-stabilized assemblies. The protein coronas substantially reduce the cellular uptake of the colloidal particles due to their increased size and the presence of HSA which is known to reduce nanoparticle-cell adhesion. On the other hand, their existence also reduces the levels of cytotoxicity of the polymeric assemblies, highlighting that protein coronas should not be always understood as artifacts that need to be eliminated due to their positive outputs.

Enhancement of Therapies for Glioblastoma (GBM) Using Nanoparticle-based Delivery Systems

Glioblastoma multiforme (GBM) is the most aggressive type of malignant brain tumor. Current FDA-approved treatments include surgical resection, radiation, and chemotherapy, while hyperthermia, immunotherapy, and most relevantly, nanoparticle (NP)-mediated delivery systems or combinations thereof have shown promise in preclinical studies. Drug-carrying NPs are a promising approach to brain delivery as a result of their potential to facilitate the crossing of the blood-brain barrier (BBB) via two main types of transcytosis mechanisms: adsorptive-mediated transcytosis (AMT) and receptor-mediated transcytosis (RMT). Their ability to accumulate in the brain can thus provide local sustained release of tumoricidal drugs at or near the site of GBM tumors. NP-based drug delivery has the potential to significantly reduce drug-related toxicity, increase specificity, and consequently improve the lifespan and quality of life of patients with GBM. Due to significant advances in the understanding of the molecular etiology and pathology of GBM, the efficacy of drugs loaded into vectors targeting this disease has increased in both preclinical and clinical settings. Multitargeting NPs, such as those incorporating multiple specific targeting ligands, are an innovative technology that can lead to decreased off-target effects while simultaneously having increased accumulation and action specifically at the tumor site. Targeting ligands can include antibodies, or fragments thereof, and peptides or small molecules, which can result in a more controlled drug delivery system compared to conventional drug treatments. This review focuses on GBM treatment strategies, summarizing current options and providing a detailed account of preclinical findings with prospective NP-based approaches aimed at improving tumor targeting and enhancing therapeutic outcomes for GBM patients.

Towards precision nanomedicine for cerebrovascular diseases with emphasis on Cerebral Cavernous Malformation (CCM)

Introduction: Cerebrovascular diseases encompass various disorders of the brain vasculature, such as ischemic/hemorrhagic strokes, aneurysms, and vascular malformations, also affecting the central nervous system leading to a large variety of transient or permanent neurological disorders. They represent major causes of mortality and long-term disability worldwide, and some of them can be inherited, including Cerebral Cavernous Malformation (CCM), an autosomal dominant cerebrovascular disease linked to mutations in CCM1/KRIT1, CCM2, or CCM3/PDCD10 genes.Areas covered: Besides marked clinical and etiological heterogeneity, some commonalities are emerging among distinct cerebrovascular diseases, including key pathogenetic roles of oxidative stress and inflammation, which are increasingly recognized as major disease hallmarks and therapeutic targets. This review provides a comprehensive overview of the different clinical features and common pathogenetic determinants of cerebrovascular diseases, highlighting major challenges, including the pressing need for new diagnostic and therapeutic strategies, and focusing on emerging innovative features and promising benefits of nanomedicine strategies for early detection and targeted treatment of such diseases.Expert opinion: Specifically, we describe and discuss the multiple physico-chemical features and unique biological advantages of nanosystems, including nanodiagnostics, nanotherapeutics, and nanotheranostics, that may help improving diagnosis and treatment of cerebrovascular diseases and neurological comorbidities, with an emphasis on CCM disease.

Addressing BBB Heterogeneity: A New Paradigm for Drug Delivery to Brain Tumors

Effective treatments for brain tumors remain one of the most urgent and unmet needs in modern oncology. This is due not only to the presence of the neurovascular unit/blood-brain barrier (NVU/BBB) but also to the heterogeneity of barrier alteration in the case of brain tumors, which results in what is referred to as the blood-tumor barrier (BTB). Herein, we discuss this heterogeneity, how it contributes to the failure of novel pharmaceutical treatment strategies, and why a "whole brain" approach to the treatment of brain tumors might be beneficial. We discuss various methods by which these obstacles might be overcome and assess how these strategies are progressing in the clinic. We believe that by approaching brain tumor treatment from this perspective, a new paradigm for drug delivery to brain tumors might be established.

Current Perspectives on Therapies, Including Drug Delivery Systems, for Managing Glioblastoma Multiforme

Glioblastoma multiforme (GBM), a standout among the most dangerous class of central nervous system (CNS) cancer, is most common and is an aggressive malignant brain tumor in adults. In spite of developments in modality therapy, it remains mostly incurable. Consequently, the need for novel systems, strategies, or therapeutic approaches for enhancing the assortment of active agents meant for GBM becomes an important criterion. Currently, cancer research focuses mainly on improving the treatment of GBM via diverse novel drug delivery systems. The treatment options at diagnosis are multimodal and include radiation therapy. Moreover, significant advances in understanding the molecular pathology of GBM and associated cell signaling pathways have opened opportunities for new therapies. Innovative treatment such as immunotherapy also gives hope for enhanced survival. The objective of this work was to collect and report the recent research findings to manage GBM. The present review includes existing novel drug delivery systems and therapies intended for managing GBM. Reported novel drug delivery systems and diverse therapies seem to be precise, secure, and relatively effective, which could lead to a new track for the obliteration of GBM.

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.

Therapeutic Delivery to the Brain via the Lymphatic Vasculature

Targeted delivery of therapeutics to disease sites has been one of the biggest challenges in medicine, as it determines the treatment efficacy of virtually all chemical and biological drugs. Furthermore, it is particularly difficult to achieve for diseases in the brain because of an additional barrier compared to other organs, the blood-brain barrier (BBB). Here, we report a new mechanism for drug delivery to the brain, nanoparticle-mediated transport through the newly discovered brain lymphatic vasculatures, bypassing the BBB and other issues associated with conventional intravenous (i.v.) administration. Using indocyanine green (ICG)-loaded PLGA nanoparticles as a model, we show that drug uptake in the brain by subcutaneous (s.c.) injection at the neck near a local lymph node is 44-fold higher than the i.v. route, resulting in effective treatment of glioblastoma in mice by photodynamic therapy. These findings will open a new paradigm for the treatment of a variety of diseases in the brain.

Self-Assembly of Integrin Ligands on the Apical Membrane Inhibits the Migration of Glioma Cells

Malignant brain cancer remains challenging in treatment due to the highly invasive quality of gliomas. Inspired by the upregulated expression of integrin β1 subunits in tumors, we designed and synthesized an integrin-targeting self-assembling ligand based on a laminin-derived peptide that selectively forms nanofibrous microdomains on the apical membrane of glioma cells, inhibiting their migration and invasion.

Nose-to-Brain Delivery of Cancer-Targeting Paclitaxel-Loaded Nanoparticles Potentiates Antitumor Effects in Malignant Glioblastoma

Glioblastoma multiforme (GBM) is an aggressive tumor with no curative treatment. The tumor recurrence after resection often requires chemotherapy or radiation to delay the infiltration of tumor remnants. Intracerebral chemotherapies are preferentially being used to prevent tumor regrowth, but treatments remain unsuccessful because of the poor drug distribution in the brain. In this study, we investigated the therapeutic efficacy of cancer-targeting arginyl-glycyl-aspartic tripeptide (RGD) conjugated paclitaxel (PTX)-loaded nanoparticles (NPs) against GBM by nose-to-brain delivery. Our results demonstrated that RGD-modified PTX-loaded NPs showed cancer-specific delivery and enhanced anticancer effects in vivo. The intranasal (IN) inoculation of RGD-PTX-loaded NPs effectively controls the tumor burden (75 ± 12% reduction) by inducing apoptosis and/or inhibiting cancer cell proliferation without affecting the G₀ stage of normal brain cells. Our data provide therapeutic evidence supporting the use of intranasally delivered cancer-targeted PTX-loaded NPs for GBM therapy.

Combination of Paclitaxel and R-flurbiprofen loaded PLGA nanoparticles suppresses glioblastoma growth on systemic administration

Malignant gliomas are highly lethal. Delivering chemotherapeutic drugs to the brain in sufficient concentration is the major limitation in their treatment due to the blood-brain barrier (BBB). Drug delivery systems may overcome this limitation and can improve the transportation through the BBB. Paclitaxel is an antimicrotubule agent with effective anticancer activity but limited BBB permeability. R-Flurbiprofen is a nonsteroidal antienflammatory drug and has potential anticancer activity. Accordingly, we designed an approach combining R-flurbiprofen and paclitaxel and positively-charged chitosan-modified poly-lactide-co-glycolic acid (PLGA) nanoparticles (NPs) and to transport them to glioma tissue. NPs were characterized and, cytotoxicity and cellular uptake studies were carried out in vitro. The in vivo efficacy of the combination and formulations were evaluated using a rat RG2 glioma tumor model. Polyethylene glycol (PEG) modified and chitosan-coated PLGA NPs demonstrated efficient cytotoxic activity and were internalized by the tumor cells in RG2 cell culture. In vivo studies showed that the chitosan-coated and PEGylated NPs loaded with paclitaxel and R-flurbiprofen exhibited significantly higher therapeutic activity against glioma. In conclusion, PLGA NPs can efficiently carry their payloads to glioma tissue and the combined use of anticancer and anti-inflammatory drugs may exert additional anti-tumor activity.

Theranostic Nanomedicine for Malignant Gliomas

Brain tumors mainly originate from glial cells and are classified as gliomas. Malignant gliomas represent an incurable disease; indeed, after surgery and chemotherapy, recurrence appears within a few months, and mortality has remained high in the last decades. This is mainly due to the heterogeneity of malignant gliomas, indicating that a single therapy is not effective for all patients. In this regard, the advent of theranostic nanomedicine, a combination of imaging and therapeutic agents, represents a strategic tool for the management of malignant brain tumors, allowing for the detection of therapies that are specific to the single patient and avoiding overdosing the non-responders. Here, recent theranostic nanomedicine approaches for glioma therapy are described.

Effects of radiation and manganese oxide nanoparticles on human glioblastoma cell line U-87 MG glycolysis

Gliomas are the most common type of malignant brain tumors. Standard treatment of gliomas consists of surgical excision of the tumor with subsequent chemotherapy and radiotherapy. Tumor cells are characterized by rapid division with an increased uptake of glucose and its catabolism during glycolysis. To maintain rapid division, the level of glycolysis of the tumor cell is significantly increased, compared with normal cells. It is known that some nanoparticles (NP) have the property of accumulating in tumors. In particular, NPs of manganese oxide can penetrate into the brain and, with considerable accumulation, cause toxic effects. These facts served as a prerequisite for studying the effects of manganese oxide NPs on the viability of glioma cells. The purpose of this work was to study the effects of manganese oxide NPs, as well as their combination with gamma irradiation on the glycolysis of glioma cells. The cells were irradiated using the research radiobiological gamma-installation IGUR-1 based on 137Cs. The level of cell glycolysis was determined using the standard glycolytic stress test on a Seahorse XFp platform. Cell viability was determined using the ViaCount reagent staining of living and dead cells. Their count was performed using flow cytometry. We showed that the glycolysis of U-87 MG glioma cells was significantly reduced when incubated for 48 hours with manganese oxide NPs. Irradiation in combination with NPs or alone did not have significant effects on glycolysis of gliomas. Glioma incubation with manganese oxide NPs for 72 hours led to a significant reduction in cell viability. This study may be useful for the development of new therapies and diagnosis of gliomas.

Applications of nanotechnology in drug delivery to the central nervous system

In recent years, the researchers and drug designers have given growing attention to new nanotechnology strategies to improve drug delivery to the central nervous system (CNS). Nanotechnology has a great potential to affect the treatment of neurological disorders, mainly Alzheimer's disease, Parkinson's disease, brain tumors, and stroke. With regard to neurodegeneration, several studies showed that nanomaterials have been successfully used for the treatments of CNS disorders. In this regard, nanocarriers have facilitated the targeted delivery of chemotherapeutics resulting in the efficient inhibition of disease progression in malignant brain tumors. Therefore, the most efficacious application of nanomaterials is the use of these substances in the treatment of CNS disease that enhances the overall effect of drug and highlights the importance of nano-therapeutics. This study was conducted to review the evidence on the applications of nanotechnology in designing drug delivery systems with the ability to cross through the blood-brain barrier (BBB) in order to transfer the therapeutic agents to the CNS.

Transferrin receptors-targeting nanocarriers for efficient targeted delivery and transcytosis of drugs into the brain tumors: a review of recent advancements and emerging trends

Treatment of glioblastoma multiforme (GBM) is a predominant challenge in chemotherapy due to the existence of blood-brain barrier (BBB) which restricts delivery of chemotherapeutic agents to the brain together with the problem of drug penetration through hard parenchyma of the GBM. With the structural and mechanistic elucidation of the BBB under both physiological and pathological conditions, it is now viable to target central nervous system (CNS) disorders utilizing the presence of transferrin (Tf) receptors (TfRs). However, overexpression of these TfRs on the GBM cell surface can also help to avoid restrictions of GBM cells to deliver chemotherapeutic agents within the tumor. Therefore, targeting of TfR-mediated delivery could counteract drug delivery issues in GBM and create a delivery system that could cross the BBB effectively to utilize ligand-conjugated drug complexes through receptor-mediated transcytosis. Hence, approach towards successful delivery of antitumor agents to the gliomas has been making possible through targeting these overexpressed TfRs within the CNS and glioma cells. This review article presents a thorough analysis of current understanding on Tf-conjugated nanocarriers as efficient drug delivery system.

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.

Bioreducible Polymeric Nanoparticles Containing Multiplexed Cancer Stem Cell Regulating miRNAs Inhibit Glioblastoma Growth and Prolong Survival

Despite our growing molecular-level understanding of glioblastoma (GBM), treatment modalities remain limited. Recent developments in the mechanisms of cell fate regulation and nanomedicine provide new avenues by which to treat and manage brain tumors via the delivery of molecular therapeutics. Here, we have developed bioreducible poly(β-amino ester) nanoparticles that demonstrate high intracellular delivery efficacy, low cytotoxicity, escape from endosomes, and promotion of cytosol-targeted environmentally triggered cargo release for miRNA delivery to tumor-propagating human cancer stem cells. In this report, we combined this nanobiotechnology with newly discovered cancer stem cell inhibiting miRNAs to develop self-assembled miRNA-containing polymeric nanoparticles (nano-miRs) to treat gliomas. We show that these nano-miRs effectively intracellularly deliver single and combination miRNA mimics that inhibit the stem cell phenotype of human GBM cells in vitro. Following direct intratumoral infusion, these nano-miRs were found to distribute through the tumors, inhibit the growth of established orthotopic human GBM xenografts, and cooperatively enhance the response to standard-of-care γ radiation. Co-delivery of two miRNAs, miR-148a and miR-296-5p, within the bioreducible nano-miR particles enabled long-term survival from GBM in mice.

Unstructured Formulation Data Analysis for the Optimization of Lipid Nanoparticle Drug Delivery Vehicles

Designing nanoparticle formulations with features tailored to their therapeutic targets in demanding timelines assumes increased importance. In this context, nanostructured lipid carriers (NLCs) offer an excellent example of a drug delivery nanosystem that has been broadly explored in the treatment of glioblastoma multiforme (GBM). Distinct fundamental NLC quality attributes can be harnessed to fit this purpose, namely particle size, size distribution, and zeta potential. These critical aspects intrinsically depend on the formulation components, influencing drug loading capacity, drug release, and stability of the NLCs. Wide variations in their composition, including the type of lipids and other surface modifier excipients, lead to differences on these parameters. NLC target product profile involves small mean particle sizes, narrow size distributions, and absolute values of zeta potential higher than 30 mV. In this work, a wealth of data previously obtained in experiments on NLC preparation, encompassing, e.g., results of preliminary studies and those of intermediate formulations, is analyzed in order to extract information useful in further optimization studies. Principal component analysis (PCA) and partial least squares (PLS) are performed to evaluate the influence of NLC composition on the respective characteristics. These methods provide a rapid and discriminatory analysis for establishing a preformulation framework, by selecting the most suitable types of lipids, surfactants, surface modifiers, and drugs, within the set of investigated variables. The results have direct implications in the optimization of formulation and processes.

Imaging and Histopathologic Nuances of Epithelioid Glioblastoma

A 27-year-old male without significant past medical history presented following collapse resulting from a syncopal episode at work. There was an episode of vomiting, and one of tonic-clonic seizure activity, which was spontaneously resolved after approximately one minute. His neurologic exam was nonfocal, with full strength in the bilateral upper and lower extremities, and no sensory deficits were elicited. MRI studies demonstrated a 4.7 cm rim-enhancing cystic mass in the right temporal-parietal region, with resultant mass effect and edema. At surgery, intraoperative pathologic consultation favoured a primary glial neoplasm. Subsequent complete histologic examination on permanent sections confirmed the presence of glioblastoma, with a morphologic pattern and immunohistochemical profile most consistent with epithelioid glioblastoma (WHO grade IV). Epithelioid glioblastoma is a rare, especially aggressive variant of IDH-wildtype glioblastoma, recognized in the 2016 World Health Organization classification. Approximately 50% of such tumors harbour the BRAF V600E mutation, which has also been observed in some melanomas where selective inhibitors have demonstrated a therapeutic role. The especially aggressive behaviour and poor clinical outcome typically observed for this variant of glioblastoma demonstrate the importance of emerging areas relevant to neurooncology, specifically those of proteomic characterization and therapeutic nanomedicine.

Drug delivery challenges and future of chemotherapeutic nanomedicine for glioblastoma treatment

Glioblastoma (GBM) is one of the most aggressive and deadliest central nervous system tumors, and the current standard treatment is surgery followed by radiotherapy with concurrent chemotherapy. Nevertheless, the survival period is notably low. Although ample research has been performed to develop an effective therapeutic strategy for treating GBM, the success of extending patients' survival period and quality of life is limited. This review focuses on the strategies developed to address the challenges associated with drug delivery in GBM, particularly nanomedicine. The first part describes major obstacles to the development of effective GBM treatment strategies. The second part focuses on the conventional chemotherapeutic nanomedicine strategies, their limitations and the novel and advanced strategies of nanomedicine, which could be promising for GBM treatment. We also highlighted the prominence of nanomedicine clinical translation. The near future looks bright following the beginning of clinical translation of nanochemotherapy for GBM.

Changes in Signal Intensity of the Dentate Nucleus and Globus Pallidus in Pediatric Patients: Impact of Brain Irradiation and Presence of Primary Brain Tumors Independent of Linear Gadolinium-based Contrast Agent Administration

Purpose To determine whether whole-brain irradiation, chemotherapy, and primary brain pathologic conditions affect magnetic resonance (MR) imaging signal changes in pediatric patients independent of the administration of gadolinium-based contrast agents (GBCAs). Materials and Methods This institutional review board-approved, HIPAA-compliant study included 144 pediatric patients who underwent intravenous GBCA-enhanced MR imaging examinations (55 patients with primary brain tumors and whole-brain irradiation, 19 with primary brain tumors and chemotherapy only, 52 with primary brain tumors without any treatment, and 18 with neuroblastoma without brain metastatic disease). The signal intensities (SIs) in the globus pallidus (GP), thalamus (T), dentate nucleus (DN), and pons (P) were measured on unenhanced T1-weighted images. GP:T and DN:P SI ratios were compared between groups by using the analysis of variance and were analyzed relative to group, total cumulative number of doses of GBCA, age, and sex by using multivariable linear models. Results DN:P ratio for the radiation therapy group was greater than that for the other groups except for the group of brain tumors treated with chemotherapy (P < .05). The number of GBCA doses was correlated with the DN:P ratio for the nontreated brain tumor group (P < .0001). The radiation therapy-treated brain tumor group demonstrated higher DN:P ratios than the nontreated brain tumor group for number of doses less than or equal to 10 (P < .0001), whereas ratios in the nontreated brain tumor group were higher than those in the radiation therapy-treated brain tumor group for doses greater than 20 (P = .05). The GP:T ratios for the brain tumor groups were greater than that for the neuroblastoma group (P = .01). Conclusion Changes in SI of the DN and GP that are independent of the administration of GBCA occur in patients with brain tumors undergoing brain irradiation, as well as in patients with untreated primary brain tumors. © RSNA, 2017.

Silica nanoparticle-induced oxidative stress and mitochondrial damage is followed by activation of intrinsic apoptosis pathway in glioblastoma cells

Introduction

Recently, the focus of oncological research has been on the optimization of therapeutic strategies targeted at malignant diseases. Nanomedicine utilizing silicon dioxide nanoparticles (SiNPs) is one such strategy and is rapidly developing as a promising tool for cancer diagnosis, imaging, and treatment. Nevertheless, little is known about the mechanisms of action of SiNPs in brain tumors.

Materials and methods

Here, we explored the effects of 5-15 nm SiNPs in the human glioblastoma cell line LN229. In this respect, MTT assays, microscopic observations, flow cytometry analyses, and luminescent assays were performed. Moreover, RT-qPCR and Western blot analyses were done to determine gene and protein expressions.

Results

We demonstrated that SiNPs triggered evident cytotoxicity, with microscopic observations of the nuclei, annexin V-fluorescein isothiocyanate/propidium iodide staining, and elevated caspase 3/7 activity, suggesting that SiNPs predominantly induced apoptotic death in LN229 cells. We further showed the occurrence of oxidative stress induced by enhanced reactive oxygen-species generation. This effect was followed by deregulated expression of genes encoding the antioxidant enzymes SOD1, SOD2, and CAT, and impaired mitochondria function. SiNP- induced mitochondrial dysfunction was characterized by membrane-potential collapse, ATP depletion, elevated expression of BAX, PUMA, and NOXA with simultaneous downregulation of BCL2/BCL2L1, and activation of caspase 9. Moreover, RT-qPCR and Western blot analyses demonstrated increased levels of the endoplasmic reticulum stress markers GRP78, GRP94, and DDIT3, as well as strongly increased expressions of the IL1B and COX2 genes, suggesting activation of endoplasmic reticulum stress and a proinflammatory response.

Conclusions

Altogether, our data indicate that in LN229 cells, SiNPs evoke cell death via activation of the intrinsic apoptosis pathway and suggest that other aspects of cellular function may also be affected. As such, SiNPs represent a potentially promising agent for facilitating further progress in brain cancer therapy. However, further exploration of SiNP long-term toxicity and molecular effects is necessary prior to their widespread application.

Therapeutic Monoclonal Antibodies Delivery for the Glioblastoma Treatment

Glioblastoma multiforme (GBM) is the most common and challenging primary malignant brain tumor, being the median overall survival between 10 and 14 months due to its invasive characteristics. GBM treatment is mainly based on the maximal surgical resection and radiotherapy associated to chemotherapy. Monoclonal antibodies (mAbs) have been used in chemotherapy protocols for GBM treatment in order to improve immunotherapy and antiangiogenic processes. High specificity and affinity of mAbs for biological targets make them highly used for brain tumor therapy. Specifically, antiangiogenic mAbs have been wisely indicated in chemotherapy protocols because GBM is the most vascularized tumors in humans with high expression of cytokines. However, mAb-based therapy is not that effective due to the aggressive spread of the tumor associated to the difficulty in the access of mAb into the brain (due to the blood-brain barrier). For that reason, nanobiotechnology has played an important role in the treatment of several tumors, mainly in the tumors of difficult access, such as GBM. In this chapter will be discussed strategies related with nanobiotechnology applied to the mAb delivery and how these therapeutics can improve the GBM treatment and life quality of the patient.

Cyclic-RGDyC functionalized liposomes for dual-targeting of tumor vasculature and cancer cells in glioblastoma: An in vitro boron neutron capture therapy study

The efficacy of boron neutron capture therapy depends on the selective delivery of ¹⁰B to the target. Integrins αvβ3 are transmembrane receptors over-expressed in both glioblastoma cells and its neovasculature. In this study, a novel approach to dual-target glioblastoma vasculature and tumor cells was investigated. Liposomes (124 nm) were conjugated with a αvβ3 ligand, cyclic arginine-glycine-aspartic acid-tyrosine-cysteine peptide (c(RGDyC)-LP) (1% molar ratio) through thiol-maleimide coupling. Expression of αvβ3 in glioblastoma cells (U87) and human umbilical vein endothelial cells (HUVEC), representing tumor angiogenesis, was determined using Western Blotting with other cells as references. The results showed that both U87 and HUVEC had stronger expression of αvβ3 than other cell types, and the degree of cellular uptake of c(RGDyC)-LP correlated with the αvβ3-expression levels of the cells. In contrast, control liposomes without c(RGDyC) showed little cellular uptake, regardless of cell type. In an in vitro boron neutron capture therapy study, the c(RGDyC)-LP containing sodium borocaptate generated more rapid and significant lethal effects to both U87 and HUVEC than the control liposomes and drug solution. Interestingly, neutron irradiated U87 and HUVEC showed different types of subsequent cell death. In conclusion, this study has demonstrated the potential of a new dual-targeting strategy using c(RGDyC)-LP to improve boron neutron capture therapy for glioblastoma.

Nanotheranostics: Emerging Strategies for Early Diagnosis and Therapy of Brain Cancer

Nanotheranostics have demonstrated the development of advanced platforms that can diagnose brain cancer at early stages, initiate first-line therapy, monitor it, and if needed, rapidly start subsequent treatments. In brain nanotheranostics, therapeutic as well as diagnostic entities are loaded in a single nanoplatform, which can be further developed as a clinical formulation for targeting various modes of brain cancer. In the present review, we concerned about theranostic nanosystems established till now in the research field. These include gold nanoparticles, carbon nanotubes, magnetic nanoparticles, mesoporous silica nanoparticles, quantum dots, polymeric nanoparticles, upconversion nanoparticles, polymeric micelles, solid lipid nanoparticles and dendrimers for the advanced detection and treatment of brain cancer with advanced features. Also, we included the role of three-dimensional models of the BBB and cancer stem cell concept for the advanced characterization of nanotheranostic systems for the unification of diagnosis and treatment of brain cancer. In future, brain nanotheranostics will be able to provide personalized treatment which can make brain cancer even remediable or at least treatable at the primary stages.

Trastuzumab distribution in an in-vivo and in-vitro model of brain metastases of breast cancer

Background

Drug and antibody delivery to brain metastases has been highly debated in the literature. The blood-tumor barrier (BTB) is more permeable than the blood-brain barrier (BBB), and has shown to have highly functioning efflux transporters and barrier properties, which limits delivery of targeted therapies.

Methods

We characterized the permeability of ¹²⁵I-trastuzumab in an in-vivo, and fluorescent trastuzumab-Rhodamine123 (t-Rho123) in a novel microfluidic in-vitro, BBB and BTB brain metastases of breast cancer model. In-vivo: Human MDA-MB-231-HER2+ metastatic breast cancer cells were grown and maintained under static conditions. Cells were harvested at 80% confluency and prepped for intra-cardiac injection into 20 homozygous female Nu/Nu mice. In-vitro: In a microfluidic device (SynVivo), human umbilical vein endothelial cells were grown and maintained under shear stress conditions in the outer compartment and co-cultured with CTX-TNA2 rat brain astrocytes (BBB) or Met-1 metastatic HER2+ murine breast cancer cells (BTB), which were maintained in the central compartment under static conditions.

Results

Tissue distribution of ¹²⁵I-trastuzumab revealed only ~3% of injected dose reached normal brain, with ~5% of injected dose reaching brain tumors. No clear correlation was observed between size of metastases and the amount of ¹²⁵I-trastuzumab localized in-vivo. This heterogeneity was paralleled in-vitro, where the distribution of t-Rho123 from the outer chamber to the central chamber of the microfluidic device was qualitatively and quantitatively analyzed over time. The rate of t-Rho123 linear uptake in the BBB (0.27 ± 0.33 × 10⁴) and BTB (1.29 ± 0.93 × 10⁴) showed to be significantly greater than 0 (p < 0.05). The BTB devices showed significant heterogenetic tendencies, as seen in in-vivo.

Conclusions

This study is one of the first studies to measure antibody movement across the blood-brain and blood-tumor barriers, and demonstrates that, though in small and most likely not efficacious quantities, trastuzumab does cross the blood-brain and blood-tumor barriers.

Recent advancements in liposomes targeting strategies to cross blood-brain barrier (BBB) for the treatment of Alzheimer's disease

In this modern era, with the help of various advanced technologies, medical science has overcome most of the health-related issues successfully. Though, some diseases still remain unresolved due to various physiological barriers. One such condition is Alzheimer; a neurodegenerative disorder characterized by progressive memory impairment, behavioral abnormalities, mood swing and disturbed routine activities of the person suffering from. It is well known to all that the brain is entirely covered by a protective layer commonly known as blood brain barrier (BBB) which is responsible to maintain the homeostasis of brain by restricting the entry of toxic substances, drug molecules, various proteins and peptides, small hydrophilic molecules, large lipophilic substances and so many other peripheral components to protect the brain from any harmful stimuli. This functionally essential structure creates a major hurdle for delivery of any drug into the brain. Still, there are some provisions on BBB which facilitate the entry of useful substances in the brain via specific mechanisms like passive diffusion, receptor-mediated transcytosis, carrier-mediated transcytosis etc. Another important factor for drug transport is the selection of a suitable drug delivery systems like, liposome, which is a novel drug carrier system offering a potential approach to resolving this problem. Its unique phospholipid bilayer structure (similar to physiological membrane) had made it more compatible with the lipoidal layer of BBB and helps the drug to enter the brain. The present review work focused on various surface modifications with functional ligand (like lactoferrin, transferrin etc.) and carrier molecules (such as glutathione, glucose etc.) on the liposomal structure to enhance its brain targeting ability towards the successful treatment of Alzheimer disease.