Recent advances in drug delivery systems for targeting brain tumors

The potential of exosomes as a new therapeutic strategy for glioblastoma

Glioblastoma (GBM) stands for the most common and aggressive type of brain tumour in adults. It is highly invasive, which explains its short rate of survival. Little is known about its risk factors, and current therapy is still ineffective. Hence, efforts are underway to develop novel and effective treatment approaches against this type of cancer. Exosomes are being explored as a promising strategy for conveying and delivering therapeutic cargo to GBM cells. They can fuse with the GBM cell membrane and, consequently, serve as delivery systems in this context. Due to their nanoscale size, exosomes can cross the blood-brain barrier (BBB), which constitutes a significant hurdle to most chemotherapeutic drugs used against GBM. They can subsequently inhibit oncogenes, activate tumour suppressor genes, induce immune responses, and control cell growth. However, despite representing a promising tool for the treatment of GBM, further research and clinical studies regarding exosome biology, engineering, and clinical applications still need to be completed. Here, we sought to review the application of exosomes in the treatment of GBM through an in-depth analysis of the scientific and clinical studies on the entire process, from the isolation and purification of exosomes to their design and transformation into anti-oncogenic drug delivery systems. Surface modification of exosomes to enhance BBB penetration and GBM-cell targeting is also a topic of discussion.

Transforming brain cancer therapeutics: unlocking the power of blood-brain barrier-targeting strategies for superior treatment outcomes and precision medicine

The treatment of brain tumors is significantly hindered by the Blood-Brain Barrier (BBB), a selective barrier that restricts the passage of therapeutic agents to the brain. Recent advancements in BBB-targeting therapies offer promising strategies to overcome this challenge, providing new avenues for the effective treatment of brain cancer. This article reviews innovative approaches, including Convection-Enhanced Delivery (CED) and RNA-based therapeutics, which enhance drug delivery directly to tumor sites, bypassing the BBB and reducing systemic toxicity. Additionally, the use of theranostic nanoparticles and CRISPR-Cas9 gene editing presents novel opportunities for real-time monitoring and precision-targeted therapy, respectively. Techniques such as magnetic nanoparticles, intranasal drug administration, and focused ultrasound with microbubbles are also being refined to improve drug penetration across the BBB. Furthermore, peptide-based delivery systems and small molecules designed to mimic endogenous transport pathways are accelerating the discovery of more effective therapies. The exploration of combination therapies that synergize BBB-penetrant drugs with conventional chemotherapeutic agents or immunotherapies holds the potential to enhance treatment efficacy and patient outcomes. Continued research and interdisciplinary collaboration are essential to develop predictive models, personalized treatment strategies, and alternative delivery methods that ensure the long-term safety and effectiveness of these novel therapies. Advancements in BBB-targeting therapeutics are poised to transform the landscape of brain cancer treatment, offering renewed hope for improved survival rates and quality of life for patients.

Stepwise-targeting and hypoxia-responsive liposome AMVY@NPs carrying siYAP and verteporfin for glioblastoma therapy

BACKGROUND

The Hippo pathway is a conserved tumour suppressor signalling pathway, and its dysregulation is often associated with abnormal cell growth and tumorigenesis. We previously revealed that the transcriptional coactivator Yes-associated protein (YAP), the key effector of the Hippo pathway, is a molecular target for glioblastoma (GBM), the most common malignant brain tumour. Inhibiting YAP with small interfering RNA (siYAP) or the specific inhibitor verteporfin (VP) can diminish GBM growth to a certain degree.

RESULTS

In this study, to enhance the anti-GBM effect of siYAP and VP, we designed stepwise-targeting and hypoxia-responsive liposomes (AMVY@NPs), which encapsulate hypoxia-responsive polymetronidazole-coated VP and DOTAP adsorbed siYAP, with angiopep-2 (A2) modification on the surface. AMVY@NPs exhibited excellent blood‒brain barrier crossing, GBM targeting, and hypoxia-responsive and efficient siYAP and VP release properties. By inhibiting the expression and function of YAP, AMVY@NPs synergistically inhibited both the growth and stemness of GBM in vitro. Moreover, AMVY@NPs strongly inhibited the growth of orthotopic U87 xenografts and improved the survival of tumour-bearing mice without adverse effects.

CONCLUSION

Specific targeting of YAP with stepwise-targeting and hypoxia-responsive liposome AMVY@NPs carrying siYAP and VP efficiently inhibited GBM progression. This study provides a valuable drug delivery platform and creative insights for molecular targeted treatment of GBM in the future.

Revealing the link between gut microbiota and brain tumor risk: a new perspective from Mendelian randomization

Background

Recent studies have shown that gut microbiota may be related to the occurrence of brain tumors, but direct evidence is lacking. This study used the Mendelian randomization study (MR) method to explore the potential causal link between gut microbiota and brain tumors.

Method

We analyzed the genome-wide association data between 211 gut microbiota taxa and brain tumors, using the largest existing gut microbiota Genome-Wide Association Studies meta-analysis data (n=13266) and combining it with brain tumor data in the IEU OpenGWAS database. We use inverse-variance weighted analysis, supplemented by methods such as Mendelian randomization-Egger regression, weighted median estimator, simple mode, and weighted mode, to assess causality. In addition, we also conducted the Mendelian randomization-Egger intercept test, Cochran's Q test, and Mendelian randomization Steiger directionality test to ensure the accuracy of the analysis. Quality control includes sensitivity analysis, horizontal gene pleiotropy test, heterogeneity test, and MR Steiger directionality test.

Result

Our study found that specific gut microbial taxa, such as order Lactobacillales and family Clostridiaceae1, were positively correlated with the occurrence of brain tumors, while genus Defluviitaleaceae UCG011 and genus Flavonifractor were negatively correlated with the occurrence of brain tumors. The Mendelian randomization-Egger intercept test showed that our analysis was not affected by pleiotropy (P>0.05).

Conclusion

This study reveals for the first time the potential causal relationship between gut microbiota and brain tumors, providing a new perspective for the prevention and treatment of early brain tumors. These findings may help develop new clinical intervention strategies and point the way for future research.

Peptide-Hitchhiking for the Development of Nanosystems in Glioblastoma

Glioblastoma (GBM) remains the epitome of aggressiveness and lethality in the spectrum of brain tumors, primarily due to the blood-brain barrier (BBB) that hinders effective treatment delivery, tumor heterogeneity, and the presence of treatment-resistant stem cells that contribute to tumor recurrence. Nanoparticles (NPs) have been used to overcome these obstacles by attaching targeting ligands to enhance therapeutic efficacy. Among these ligands, peptides stand out due to their ease of synthesis and high selectivity. This article aims to review single and multiligand strategies critically. In addition, it highlights other strategies that integrate the effects of external stimuli, biomimetic approaches, and chemical approaches as nanocatalytic medicine, revealing their significant potential in treating GBM with peptide-functionalized NPs. Alternative routes of parenteral administration, specifically nose-to-brain delivery and local treatment within the resected tumor cavity, are also discussed. Finally, an overview of the significant obstacles and potential strategies to overcome them are discussed to provide a perspective on this promising field of GBM therapy.

Amphiphilic hydroxyethyl starch-based nanoparticles carrying linoleic acid modified berberine inhibit the expression of krasv12 oncogene in zebrafish

Cancer is one of the most lethal diseases all over the world. Despite that many drugs have been developed for cancer therapy, they still suffer from various limitations including poor treating efficacy, toxicity to normal human cells, and the emergence of multidrug resistance. In this study, the amphiphilic LHES polymers were prepared using hydroxyethyl starch (HES) and linoleic acid as starting materials. The content and substitution degree of linoleic acid groups in LHES polymers were analyzed. The LHES polymers were used for fabricating LHES-B nanoparticles carrying a linoleic acid modified berberine derivative (L-BBR). The LHES-B nanoparticles showed high drug loading efficiency (29%) and could quickly release L-BBR under acidic pH condition (pH = 4.5). Biological investigations revealed that LHES-B nanoparticles significantly inhibited the proliferation of HepG2 cells and exhibited higher cytotoxicity than L-BBR. In a transgenic Tg(fabp10:rtTA2s-M2; TRE2:EGFP-krasv12) zebrafish model, LHES-B nanoparticles obviously inhibited the expression of krasv12 oncogene. These results indicated that LHES carriers could improve the anticancer activity of L-BBR, and the synthesized LHES-B nanoparticles showed great potential as anticancer drug.

A viral attack on brain tumors: the potential of oncolytic virus therapy

Managing malignant brain tumors remains a significant therapeutic hurdle that necessitates further research to comprehend their treatment potential fully. Oncolytic viruses (OVs) offer many opportunities for predicting and combating tumors through several mechanisms, with both preclinical and clinical studies demonstrating potential. OV therapy has emerged as a potent and effective method with a dual mechanism. Developing innovative and effective strategies for virus transduction, coupled with immune checkpoint inhibitors or chemotherapy drugs, strengthens this new technique. Furthermore, the discovery and creation of new OVs that can seamlessly integrate gene therapy strategies, such as cytotoxic, anti-angiogenic, and immunostimulatory, are promising advancements. This review presents an overview of the latest advancements in OVs transduction for brain cancer, focusing on the safety and effectiveness of G207, G47Δ, M032, rQNestin34.5v.2, C134, DNX-2401, Ad-TD-nsIL12, NSC-CRAd-S-p7, TG6002, and PVSRIPO. These are evaluated in both preclinical and clinical models of various brain tumors.

Conjugation of sulpiride with a cell penetrating peptide to augment the antidepressant efficacy and reduce serum prolactin levels

Depression ranks as the fourth most prevalent global disease, with suicide incidents occurring at a younger age. Sulpiride (SUL), an atypical antidepressant drug acting as a dopamine D2 receptor antagonist and possessing anti-inflammatory properties, exhibits limited ability to penetrate the blood brain barrier (BBB). This weak penetration hampers its inhibitory effect on prolactin release in the pituitary gland, consequently leading to hyperprolactinemia. In order to enhance the central nervous system efficacy of sulpiride and reduce serum prolactin levels, we covalently linked sulpiride to VPALR derived from the nuclear DNA repair protein ku70. In vivo study on depressive mice using intraperitoneal injection of VPALR-SUL demonstrated a significant increase in struggle time and total distance compared to those treated with only sulpiride while also reducing serum prolactin concentration. The pharmacokinetic study results showed that VPALR-SUL prolonged half-life and increased bioavailability. In conclusion, VPALR-SUL exhibited potential for enhancing sulpiride transport across the BBB, augmenting its antidepressant effects, and reducing serum prolactin levels. This study laid a foundation for improving sulpiride delivery and developing novel antidepressants.

Emerging non-antibody‒drug conjugates (non-ADCs) therapeutics of toxins for cancer treatment

The non-selective cytotoxicity of toxins limits the clinical relevance of the toxins. In recent years, toxins have been widely used as warheads for antibody‒drug conjugates (ADCs) due to their efficient killing activity against various cancer cells. Although ADCs confer certain targeting properties to the toxins, low drug loading capacity, possible immunogenicity, and other drawbacks also limit the potential application of ADCs. Recently, non-ADC delivery strategies for toxins have been extensively investigated. To further understand the application of toxins in anti-tumor, this paper provided an overview of prodrugs, nanodrug delivery systems, and biomimetic drug delivery systems. In addition, toxins and their combination strategies with other therapies were discussed. Finally, the prospect and challenge of toxins in cancer treatment were also summarized.

Tuneable hydrogel patterns in pillarless microfluidic devices

Organ-on-chip (OOC) technology has recently emerged as a powerful tool to mimic physiological or pathophysiological conditions through cell culture in microfluidic devices. One of its main goals is bypassing animal testing and encouraging more personalized medicine. The recent incorporation of hydrogels as 3D scaffolds into microfluidic devices has changed biomedical research since they provide a biomimetic extracellular matrix to recreate tissue architectures. However, this technology presents some drawbacks such as the necessity for physical structures as pillars to confine these hydrogels, as well as the difficulty in reaching different shapes and patterns to create convoluted gradients or more realistic biological structures. In addition, pillars can also interfere with the fluid flow, altering the local shear forces and, therefore, modifying the mechanical environment in the OOC model. In this work, we present a methodology based on a plasma surface treatment that allows building cell culture chambers with abutment-free patterns capable of producing precise shear stress distributions. Therefore, pillarless devices with arbitrary geometries are needed to obtain more versatile, reliable, and biomimetic experimental models. Through computational simulation studies, these shear stress changes are demonstrated in different designed and fabricated geometries. To prove the versatility of this new technique, a blood-brain barrier model has been recreated, achieving an uninterrupted endothelial barrier that emulates part of the neurovascular network of the brain. Finally, we developed a new technology that could avoid the limitations mentioned above, allowing the development of biomimetic OOC models with complex and adaptable geometries, with cell-to-cell contact if required, and where fluid flow and shear stress conditions could be controlled.

Nanoparticle-Based Combinational Strategies for Overcoming the Blood-Brain Barrier and Blood-Tumor Barrier

The blood-brain barrier (BBB) and blood-tumor barrier (BTB) pose substantial challenges to efficacious drug delivery for glioblastoma multiforme (GBM), a primary brain tumor with poor prognosis. Nanoparticle-based combinational strategies have emerged as promising modalities to overcome these barriers and enhance drug penetration into the brain parenchyma. This review discusses various nanoparticle-based combinatorial approaches that combine nanoparticles with cell-based drug delivery, viral drug delivery, focused ultrasound, magnetic field, and intranasal drug delivery to enhance drug permeability across the BBB and BTB. Cell-based drug delivery involves using engineered cells as carriers for nanoparticles, taking advantage of their intrinsic migratory and homing capabilities to facilitate the transport of therapeutic payloads across BBB and BTB. Viral drug delivery uses engineered viral vectors to deliver therapeutic genes or payloads to specific cells within the GBM microenvironment. Focused ultrasound, coupled with microbubbles or nanoparticles, can temporarily disrupt the BBB to increase drug permeability. Magnetic field-guided drug delivery exploits magnetic nanoparticles to facilitate targeted drug delivery under an external magnetic field. Intranasal drug delivery offers a minimally invasive avenue to bypass the BBB and deliver therapeutic agents directly to the brain via olfactory and trigeminal pathways. By combining these strategies, synergistic effects can enhance drug delivery efficiency, improve therapeutic efficacy, and reduce off-target effects. Future research should focus on optimizing nanoparticle design, exploring new combination strategies, and advancing preclinical and clinical investigations to promote the translation of nanoparticle-based combination therapies for GBM.

Genetically modified ZIKA virus as a microRNA-sensitive oncolytic virus against central nervous system tumors

Here we introduce a first-in-class microRNA-sensitive oncolytic Zika virus (ZIKV) for virotherapy application against central nervous system (CNS) tumors. The described methodology produced two synthetic modified ZIKV strains that are safe in normal cells, including neural stem cells, while preserving brain tropism and oncolytic effects in tumor cells. The microRNA-sensitive ZIKV introduces genetic modifications in two different virus sites: first, in the established 3'UTR region, and secondly, in the ZIKV protein coding sequence, demonstrating for the first time that the miRNA inhibition systems can be functional outside the UTR RNA sites. The total tumor remission in mice bearing human CNS tumors, including metastatic tumor growth, after intraventricular and systemic modified ZIKV administration, confirms the promise of this virotherapy as a novel agent against brain tumors-highly deadly diseases in urgent need of effective advanced therapies.

Naringenin Nanoformulations for Neurodegenerative Diseases

Glioblastoma (GBM) is a grade-IV astrocytoma, which is the most common and aggressive type of brain tumor, spreads rapidly and has a life-threatening catastrophic effect. GBM mostly occurs in adults with an average survival time of 15 to 18 months, and the overall mortality rate is 5%. Significant invasion and drug resistance activity cause the poor diagnosis of GBM. Naringenin (NRG) is a plant secondary metabolite byproduct of the flavanone subgroup. NRG can cross the blood-brain barrier and deliver drugs into the central nervous system when conjugated with appropriate nanocarriers to overcome the challenges associated with gliomas through naringenin-loaded nanoformulations. Here, we discuss several nanocarriers employed that are as delivery systems, such as polymeric nanoparticles, micelles, liposomes, solid lipid nanoparticles (SLNs), nanosuspensions, and nanoemulsions. These naringenin-loaded nanoformulations have been tested in various in vitro and in vivo models as a potential treatment for brain disorders. This review nanoformulations of NRG can a possible therapeutic alternative for the treatment of neurological diseases are discussed.

Progress and Challenges in the Diagnosis and Treatment of Brain Cancer Using Nanotechnology

Primary brain cancer or brain cancer is the overgrowth of abnormal or malignant cells in the brain or its nearby tissues that form unwanted masses called brain tumors. People with malignant brain tumors suffer a lot, and the expected life span of the patients after diagnosis is often only around 14 months, even with the most vigorous therapies. The blood-brain barrier (BBB) is the main barrier in the body that restricts the entry of potential chemotherapeutic agents into the brain. The chances of treatment failure or low therapeutic effects are some significant drawbacks of conventional treatment methods. However, recent advancements in nanotechnology have generated hope in cancer treatment. Nanotechnology has shown a vital role starting from the early detection, diagnosis, and treatment of cancer. These tiny nanomaterials have great potential to deliver drugs across the BBB. Beyond just drug delivery, nanomaterials can be simulated to generate fluorescence to detect tumors. The current Review discusses in detail the challenges of brain cancer treatment and the application of nanotechnology to overcome those challenges. The success of chemotherapeutic treatment or the surgical removal of tumors requires proper imaging. Nanomaterials can provide imaging and therapeutic benefits for cancer. The application of nanomaterials in the diagnosis and treatment of brain cancer is discussed in detail by reviewing past studies.

Cytotoxicity of poly-guanidine in medulloblastoma cell lines

Medulloblastoma (MB) is the most common pediatric brain tumor. The therapy frequently causes serious side effects, and new selective therapies are needed. MB expresses hyper sialylation, a possible target for selective therapy. The cytotoxic efficacy of a poly guanidine conjugate (GuaDex) incubated with medulloblastoma cell cultures (DAOY and MB-LU-181) was investigated. The cells were incubated with 0.05-8 µM GuaDex from 15 min to 72 h. A fluorometric cytotoxicity assay (FMCA) measured the cytotoxicity. Labeled GuaDex was used to study tumor cell interaction. FITC-label Sambucus nigra confirmed high expression of sialic acid (Sia). Immunofluorescence microscopy was used to visualize the cell F-actin and microtubules. The cell interactions were studied by confocal and fluorescence microscopy. Annexin-V assay was used to detect apoptosis. Cell cycle analysis was done by DNA content determination. A wound-healing migration assay determined the effects on the migratory ability of DAOY cells after GuaDex treatment. IC50 for GuaDex was 223.4 -281.1 nM. FMCA showed potent growth inhibition on DAOY and MB-LU-181 cells at 5 uM GuaDex after 4 h of incubation. GuaDex treatment induced G2/M phase cell cycle arrest. S. nigra FITC-label lectin confirmed high expression of Sia on DAOY medulloblastoma cells. The GuaDex treatment polymerized the cytoskeleton (actin filaments and microtubules) and bound to DNA, inducing condensation. The Annexin V assay results were negative. Cell migration was inhibited at 0.5 µM GuaDex concentration after 24 h of incubation. GuaDex showed potent cytotoxicity and invasion-inhibitory effects on medulloblastoma cells at low micromolar concentrations. GuaDex efficacy was significant and warrants further studies.

Targeted transport of biotherapeutics at the blood-brain barrier

INTRODUCTION

The treatment of neurological diseases is significantly hampered by the lack of available therapeutics. A major restraint for the development of drugs is denoted by the presence of the blood-brain barrier (BBB), which precludes the transfer of biotherapeutics to the brain due to size restraints.

AREAS COVERED

Novel optimism for transfer of biotherapeutics to the brain has been generated via development of targeted therapeutics to nutrient transporters expressed by brain capillary endothelial cells (BCECs). Targeting approaches with antibodies acting as biological drug carriers allow for proteins and genetic material to enter the brain, and qualified therapy using targeted proteins for protein replacement has been observed in preclinical models and now emerging in the clinic. Viral vectors denote an alternative for protein delivery to the brain by uptake and transduction of BCECs, or by transport through the BBB leading to neuronal transduction.

EXPERT OPINION

The breaching of the BBB to large molecules has opened for treatment of diseases in the brain. A sturdier understanding of how biotherapeutics undergo transport through the BBB and how successful transport into the brain can be monitored is required to further improve the translation from successful preclinical studies to the clinic.

Influence factors on and potential strategies to amplify receptor-mediated nanodrug delivery across the blood-brain barrier

INTRODUCTION

A major challenge in treating central nervous system (CNS) disorders is to achieve adequate drug delivery across the blood-brain barrier (BBB). Receptor-mediated nanodrug delivery as a Trojan horse strategy has become an exciting approach. However, these nanodrugs do not accumulate significantly in the brain parenchyma, which greatly limits the therapeutic effect of drugs. Amplifying the efficiency of receptor-mediated nanodrug delivery across the BBB becomes the holy grail in the treatment of CNS disorders.

AREAS COVERED

In this review, we tend to establish links between dynamic BBB and receptor-mediated nanodrug delivery, starting with the delivery processes across the BBB, describing factors affecting nanodrug delivery efficiency, and summarizing potential strategies that may amplify delivery efficiency.

EXPERT OPINION

Receptor-mediated nanodrug delivery is a common approach to significantly enhance the efficiency of brain-targeting delivery. As BBB is constantly undergoing changes, it is essential to investigate the impact of diseases on the effectiveness of brain-targeting nanodrug delivery. More critically, there are several barriers to achieving brain-targeting nanodrug delivery in the five stages of receptor-mediated transcytosis (RMT), and the impacts can be conflicting, requiring intricate balance. Further studies are also needed to investigate the material toxicity of nanodrugs to address the issue of clinical translation.

Towards Novel Biomimetic In Vitro Models of the Blood-Brain Barrier for Drug Permeability Evaluation

Current available animal and in vitro cell-based models for studying brain-related pathologies and drug evaluation face several limitations since they are unable to reproduce the unique architecture and physiology of the human blood-brain barrier. Because of that, promising preclinical drug candidates often fail in clinical trials due to their inability to penetrate the blood-brain barrier (BBB). Therefore, novel models that allow us to successfully predict drug permeability through the BBB would accelerate the implementation of much-needed therapies for glioblastoma, Alzheimer's disease, and further disorders. In line with this, organ-on-chip models of the BBB are an interesting alternative to traditional models. These microfluidic models provide the necessary support to recreate the architecture of the BBB and mimic the fluidic conditions of the cerebral microvasculature. Herein, the most recent advances in organ-on-chip models for the BBB are reviewed, focusing on their potential to provide robust and reliable data regarding drug candidate ability to reach the brain parenchyma. We point out recent achievements and challenges to overcome in order to advance in more biomimetic in vitro experimental models based on OOO technology. The minimum requirements that should be met to be considered biomimetic (cellular types, fluid flow, and tissular architecture), and consequently, a solid alternative to in vitro traditional models or animals.

Applications and Future Prospects of Micro/Nanorobots Utilizing Diverse Biological Carriers

Targeted drug delivery using micro-nano robots (MNRs) is a rapidly advancing and promising field in biomedical research. MNRs enable precise delivery of drugs, addressing a wide range of healthcare needs. However, the application of MNRs in vivo is limited by power issues and specificity in different scenarios. Additionally, the controllability and biological safety of MNRs must be considered. To overcome these challenges, researchers have developed bio-hybrid micro-nano motors that offer improved accuracy, effectiveness, and safety for targeted therapies. These bio-hybrid micro-nano motors/robots (BMNRs) use a variety of biological carriers, blending the benefits of artificial materials with the unique features of different biological carriers to create tailored functions for specific needs. This review aims to give an overview of the current progress and application of MNRs with various biocarriers, while exploring the characteristics, advantages, and potential hurdles for future development of these bio-carrier MNRs.

Dendrimer: An update on recent developments and future opportunities for the brain tumors diagnosis and treatment

A brain tumor is an uncontrolled cell proliferation, a mass of tissue composed of cells that grow and divide abnormally and appear to be uncontrollable by the processes that normally control normal cells. Approximately 25,690 primary malignant brain tumors are discovered each year, 70% of which originate in glial cells. It has been observed that the blood-brain barrier (BBB) limits the distribution of drugs into the tumour environment, which complicates the oncological therapy of malignant brain tumours. Numerous studies have found that nanocarriers have demonstrated significant therapeutic efficacy in brain diseases. This review, based on a non-systematic search of the existing literature, provides an update on the existing knowledge of the types of dendrimers, synthesis methods, and mechanisms of action in relation to brain tumours. It also discusses the use of dendrimers in the diagnosis and treatment of brain tumours and the future possibilities of dendrimers. Dendrimers are of particular interest in the diagnosis and treatment of brain tumours because they can transport biochemical agents across the BBB to the tumour and into the brain after systemic administration. Dendrimers are being used to develop novel therapeutics such as prolonged release of drugs, immunotherapy, and antineoplastic effects. The use of PAMAM, PPI, PLL and surface engineered dendrimers has proven revolutionary in the effective diagnosis and treatment of brain tumours.