Brain Tumor Drug Research Articles

Surface Modified Glucose‐Derived, Blood–Brain Barrier‐Crossing Nanospheres Dually Targets Macrophage and Cancer Cells for Effective In Situ Anti‐Glioma Effect

AbstractGlucose‐derived carbon nanospheres (CSP), uniquely derived by hydrothermal condensation process, inherently cross blood–brain‐barrier (BBB) but distribute all over the brain. Albeit its potential to treat glioma as an effective drug delivery system, it is challenging to restrict drug‐associated CSP within the glioma region and reduce non‐specific side effects. Incidentally, gliomas moderately express sigma receptors (SR). Earlier, a cationic lipid‐conjugated neuropsychotic drug, haloperidol (H8) is developed with SR‐targetability and anticancer effect but with zero BBB‐crossing ability. In this study, the CSP surface is modified with H8 (CH8 nano‐conjugate) and dual targeting is achieved within glioma‐tumor microenvironment: 1) glioma cells and 2) pro‐proliferative M2 tumor‐associated macrophages (TAM), as both express SR. CH8‐treatment increases the survivability of orthotopic glioma‐tumor bearing mice and significantly reduces tumor burden in the glioma‐subcutaneous model. Further CH8‐surface is modified by combining the brain tumor drug, carmustine (CH8‐CRM). CH8‐CRM nano‐conjugate selectively enhances the survivability of orthotopic glioma‐carrying mice and reduces tumor aggressiveness significantly in comparison to other treatment groups. Lysates from CH8‐CRM‐treated tumor show upregulation of cleaved‐caspase 3, p53, but downregulation of pAkt. The combination treatment pronouncedly enhances the anti‐glioma effect of H8. Conclusively, CH8‐mediated dual‐targeting via SR within orthotopic glioma‐associated mice exemplifies the repurposing of neuropsychotic drugs for treating glioma.

Challenges, limitations, and pitfalls of PET and advanced MRI in patients with brain tumors: A report of the PET/RANO group.

Brain tumor diagnostics have significantly evolved with the use of positron emission tomography (PET) and advanced magnetic resonance imaging (MRI) techniques. In addition to anatomical MRI, these modalities may provide valuable information for several clinical applications such as differential diagnosis, delineation of tumor extent, prognostication, differentiation between tumor relapse and treatment-related changes, and the evaluation of response to anticancer therapy. In particular, joint recommendations of the Response Assessment in Neuro-Oncology (RANO) Group, the European Association of Neuro-oncology, and major European and American Nuclear Medicine societies highlighted that the additional clinical value of radiolabeled amino acids compared to anatomical MRI alone is outstanding and that its widespread clinical use should be supported. For advanced MRI and its steadily increasing use in clinical practice, the Standardization Subcommittee of the Jumpstarting Brain Tumor Drug Development Coalition provided more recently an updated acquisition protocol for the widely used dynamic susceptibility contrast perfusion MRI. Besides amino acid PET and perfusion MRI, other PET tracers and advanced MRI techniques (e.g. MR spectroscopy) are of considerable clinical interest and are increasingly integrated into everyday clinical practice. Nevertheless, these modalities have shortcomings which should be considered in clinical routine. This comprehensive review provides an overview of potential challenges, limitations, and pitfalls associated with PET imaging and advanced MRI techniques in patients with gliomas or brain metastases. Despite these issues, PET imaging and advanced MRI techniques continue to play an indispensable role in brain tumor management. Acknowledging and mitigating these challenges through interdisciplinary collaboration, standardized protocols, and continuous innovation will further enhance the utility of these modalities in guiding optimal patient care.

Childhood Brain Tumors: A Review of Strategies to Translate CNS Drug Delivery to Clinical Trials.

Brain and spinal tumors affect 1 in 1000 people by 25 years of age, and have diverse histological, biological, anatomical and dissemination characteristics. A mortality of 30-40% means the majority are cured, although two-thirds have life-long disability, linked to accumulated brain injury that is acquired prior to diagnosis, and after surgery or chemo-radiotherapy. Only four drugs have been licensed globally for brain tumors in 40 years and only one for children. Most new cancer drugs in clinical trials do not cross the blood-brain barrier (BBB). Techniques to enhance brain tumor drug delivery are explored in this review, and cover those that augment penetration of the BBB, and those that bypass the BBB. Developing appropriate delivery techniques could improve patient outcomes by ensuring efficacious drug exposure to tumors (including those that are drug-resistant), reducing systemic toxicities and targeting leptomeningeal metastases. Together, this drug delivery strategy seeks to enhance the efficacy of new drugs and enable re-evaluation of existing drugs that might have previously failed because of inadequate delivery. A literature review of repurposed drugs is reported, and a range of preclinical brain tumor models available for translational development are explored.

Advances in Tumor Organoids for the Evaluation of Drugs: A Bibliographic Review.

Tumor organoids are defined as self-organized three-dimensional assemblies of heterogeneous cell types derived from patient samples that mimic the key histopathological, genetic, and phenotypic characteristics of the original tumor. This technology is proposed as an ideal candidate for the evaluation of possible therapies against cancer, presenting advantages over other models which are currently used. However, there are no reports in the literature that relate the techniques and material development of tumor organoids or that emphasize in the physicochemical and biological properties of materials that intent to biomimicry the tumor extracellular matrix. There is also little information regarding the tools to identify the correspondence of native tumors and tumoral organoids (tumoroids). Moreover, this paper relates the advantages of organoids compared to other models for drug evaluation. A growing interest in tumoral organoids has arisen from 2009 to the present, aimed at standardizing the process of obtaining organoids, which more accurately resemble patient-derived tumor tissue. Likewise, it was found that the characteristics to consider for the development of organoids, and therapeutic responses of them, are cell morphology, physiology, the interaction between cells, the composition of the cellular matrix, and the genetic, phenotypic, and epigenetic characteristics. Currently, organoids have been used for the evaluation of drugs for brain, lung, and colon tumors, among others. In the future, tumor organoids will become closer to being considered a better model for studying cancer in clinical practice, as they can accurately mimic the characteristics of tumors, in turn ensuring that the therapeutic response aligns with the clinical response of patients.

NQPC-5 JAPAN BRAIN TUMOR ALLIANCE: ACHIEVEMENTS IN 2021-2022 AND PATIENT VOICE

Abstract Brain tumors are a major shock at diagnosis for patients and families, and their journey is impacted in various and complex ways, not only physically but mentally, financially and socially. The Japan Brain Tumor Alliance is a non-profit organization, established in 2006 to support patients and their families. As our key activity, JBTA offers patient-gathering meetings on the regular basis so that patients and families could openly share their concerns and experience. As JBTA collaborates with healthcare professionals, the up-to-date information is provided to patients and families and their needs are shared to the healthcare professionals. JBTA's achievements in 2021-2022 include the review of clinical guidelines, information-sharing events with the Japan Clinical Oncology Group and a seminar by a certified specialist regarding the social support system in Japan. With the active collaboration with other patient advocate groups, multiple petitions have been submitted to pursue further development of drugs for brain tumors. JBTA is also focusing on to provide the information to community through its website and SNS, including the stories of personal journey described by patients and families.Each of brain tumor patients and families has their own needs. Through the discussion at JBTA's monthly meetings and our online communication, they could express their real voice to the peers. JBTA picks up these issues that patients and families are facing and presents the necessity of working on their unmet needs.

Nucleic acid-based therapy for brain cancer: Challenges and strategies.

Nucleic acid-based therapy emerges as a powerful weapon for the treatment of tumors thanks to its direct, effective, and lasting therapeutic effect. Encouragingly, continuous nucleic acid-based drugs have been approved by the Food and Drug Administration (FDA) and the European Medicines Agency (EMA). Despite the tremendous progress, there are few nucleic acid-based drugs for brain tumors in clinic. The most challenging problems lie on the instability of nucleic acids, difficulty in traversing the biological barriers, and the off-target effect. Herein, nucleic acid-based therapy for brain tumor is summarized considering three aspects: (i) the therapeutic nucleic acids and their applications in clinical trials; (ii) the various administration routes for nucleic acid delivery and the respective advantages and drawbacks. (iii) the strategies and carriers for improving stability and targeting ability of nucleic acid drugs. This review provides thorough knowledge for the rational design of nucleic acid-based drugs against brain tumor.

Working Together to Accelerate the Preclinical to Clinical Translation of Drug Delivery Systems for Children’s Brain Tumours

Abstract AIMS Several techniques, such as intra-cerebrospinal fluid chemotherapy, ultrasound-mediated blood-brain barrier disruption, convection enhanced delivery, polymer delivery systems, electric field therapy, and intra-arterial and intra-nasal chemotherapy, have the potential to transform the treatment of brain tumours in children. However, there have been very few clinical trials to evaluate these. We aim to address challenges in the pre-clinical to clinical research pathway for CNS drug delivery systems in order to increase the number of clinical trials in this area. METHOD In 2021, the CBTDDC (Children’s Brain Tumour Drug Delivery Consortium) and the ITCC (Innovative Therapies for Children with Cancer) brain tumour group established a Clinical Trials Working Group comprising international researchers and clinicians to address this issue. RESULTS This partnership highlighted the main challenges as: (1) a lack of specific funding for prototype development and/or scale-up for clinical trials; (2) difficulties in navigating the regulatory landscape; (3) lack of accurate preclinical models; and (4) increased need for multi-centric working. In response to this, we ran a workshop on ‘Clinical Trial Readiness’, attended by around 50 delegates (comprising clinicians, researchers, trial regulatory experts, policy makers, and representatives from funding organisations, brain tumour charities and industry). CONCLUSION We have now established speciality-specific working groups with the aim of producing recommendations around the use of preclinical models and drug delivery techniques according to brain tumour type. We have also created a ‘Roadmap’ document for preclinical to clinical translation, which will be freely shared with the neuro-oncology research community.

Construction of a novel blood brain barrier-glioma microfluidic chip model: Applications in the evaluation of permeability and anti-glioma activity of traditional Chinese medicine components

Since most anti-glioma drug candidates hardly permeate through the blood-brain barrier (BBB), preclinical models that can integrate the complexity of the tumor microenvironment and the structure and function of the BBB is urgently needed for the treatment of glioma. Herein, we constructed an in vitro BBB-glioma microfluidic chip model lined by primary human brain microvascular endothelial cells, pericytes, astrocytes and glioma cells, which could recapitulate the high level of barrier function of the in vivo human BBB and glioma microenvironment. The BBB unit in BBB-glioma microfluidic chip (BBB–U251 chip) displayed selective permeability to fluorescein isothiocyanate isomer-dextran (FITC-dextran) with different molecular weights and three model drugs with different permeability behavior across BBB, which indicated that this glioma model included a functional barrier. Six potential anti-glioma components in traditional Chinese medicine (TCM) were delivered into the blood channel and the permeated amount was quantified by high-performance liquid chromatography combined with ultraviolet (HPLC-UV). The permeated drugs then directly acted on 3D cultured glioma cells (U251) to evaluate the drug efficacy. The results of permeability coefficients of drugs showed that the data were closer to the in vivo data of traditional Transwell model. The effect of the drugs on U251 cells in the BBB-U251 chip was significantly lower due to the existence of BBB. Drug responses on glioma demonstrated the necessity to take BBB into account during the development of anti-glioma new drugs. Therefore, this 3D glioma microfluidic models integrating the BBB functionality can be a useful platform for screening the anticancer drug for brain tumors.

Micro-Nanocarriers Based Drug Delivery Technology for Blood-Brain Barrier Crossing and Brain Tumor Targeting Therapy.

The greatest obstacle to using drugs to treat brain tumors is the blood-brain barrier (BBB), making it difficult for conventional drug molecules to enter the brain. Therefore, how to safely and effectively penetrate the BBB to achieve targeted drug delivery to brain tumors has been a challenging research problem. With the intensive research in micro- and nanotechnology in recent years, nano drug-targeted delivery technologies have shown great potential to overcome this challenge, such as inorganic nanocarriers, organic polymer-carriers, liposomes, and biobased carriers, which can be designed in different sizes, shapes, and surface functional groups to enhance their ability to penetrate the BBB and targeted drug delivery for brain tumors. In this review, the composition and overcoming patterns of the BBB are detailed, and then the hot research topics of drug delivery carriers for brain tumors in recent years are summarized, and their mechanisms of action on the BBB and the factors affecting drug delivery are described in detail, and the effectiveness of targeted therapy for brain tumors is evaluated. Finally, the challenges and dilemmas in developing brain tumor drug delivery systems are discussed, which will be promising in the future for targeted drug delivery to brain tumors based on micro-nanocarriers technology.

Tumor-targeting cell-penetrating peptide, p28, for glioblastoma imaging and therapy.

Despite recent advances in cancer research, glioblastoma multiforme (GBM) remains a highly aggressive brain tumor as its treatment options are limited. The current standard treatment includes surgery followed by radiotherapy and adjuvant chemotherapy. However, surgery without image guidance is often challenging to achieve maximal safe resection as it is difficult to precisely discern the lesion to be removed from surrounding brain tissue. In addition, the efficacy of adjuvant chemotherapy is limited by poor penetration of therapeutics through the blood-brain barrier (BBB) into brain tissues, and the lack of tumor targeting. In this regard, we utilized a tumor-targeting cell-penetration peptide, p28, as a therapeutic agent to improve the efficacy of a current chemotherapeutic agent for GBM, and as a carrier for a fluorescence imaging agent for a clear identification of GBM. Here, we show that a near-infrared (NIR) imaging agent, ICG-p28 (a chemical conjugate of an FDA-approved NIR dye, indocyanine green ICG, and tumor-targeting p28 peptide) can preferentially localize tumors in multiple GBM animal models. Moreover, xenograft studies show that p28, as a therapeutic agent, can enhance the cytotoxic activity of temozolomide (TMZ), one of the few effective drugs for brain tumors. Collectively, our findings highlight the important role of the tumor-targeting peptide, which has great potential for intraoperative image-guided surgery and the development of new therapeutic strategies for GBM.

EPCT-03. Working together to accelerate the preclinical to clinical translation of drug delivery systems for children’s brain tumours

Children's brain tumours are the biggest cancer killer in children and young adults. Several techniques, such as intra-cerebrospinal fluid chemotherapy, ultrasound-mediated blood-brain barrier disruption, convection enhanced delivery, polymer delivery systems, electric field therapy, and intra-arterial and intra-nasal chemotherapy, have the potential to transform the treatment of brain tumours in children. However, there have been very few clinical trials to evaluate these. In 2021, the CBTDDC (Children’s Brain Tumour Drug Delivery Consortium) and the ITCC (Innovative Therapies for Children with Cancer) brain tumour group established a Clinical Trials Working Group comprising international researchers and clinicians to address this issue. This partnership highlighted the main challenges in preclinical to clinical translation of paediatric CNS drug delivery as: (1) a lack of specific funding for prototype development and/or scale-up for clinical trials; (2) difficulties in navigating the regulatory landscape; (3) lack of accurate preclinical models; and (4) increased need for multi-centric working. In response to this, we ran a hybrid workshop in November 2021 on ‘Clinical Trial Readiness for CNS Drug Delivery’. At this workshop, around 50 delegates (comprising clinicians, researchers, trial regulatory experts, policy makers, and representatives from funding organisations, brain tumour charities and industry) came together to discuss issues around funding, preclinical models and regulatory processes. We have established speciality-specific working groups to build on the workshop discussions, with the aim of producing recommendations around the use of preclinical models and drug delivery techniques according to brain tumour type. We have also used the workshop presentations and discussions to create a ‘Roadmap’ document for preclinical to clinical translation, which will be freely shared with the neuro-oncology research community. We continue to liaise with funders and regulatory bodies to address the changes that are needed in these areas. If you would like to join our network, contact: cbtddc@nottingham.ac.uk

Multifunctional exosome-mimetics for targeted anti-glioblastoma therapy by manipulating protein corona

Targeted drug delivery to the glioblastoma (GBM) overcoming blood–brain barrier (BBB) has been challenging. Exosomes are promising vehicles for brain tumor drug delivery, but the production and purification hinder its application for nanomedicine. Besides, the formation of protein corona (PC) may affect the behaviour of nanocarriers. Here, multifunctional exosomes-mimetics (EM) are developed and decorated with angiopep-2 (Ang) for enhancing GBM drug delivery by manipulating PC. Docetaxel (DTX)-loaded EM with Ang modification (DTX@Ang-EM) show less absorption of serum proteins and phagocytosis by macrophages. Ang-EM show enhanced BBB penetration ability and targeting ability to the GBM. Ang-EM-mediated delivery increase the concentration of DTX in the tumor area. The multifunctional DTX@Ang-EM exhibits significant inhibition effects on orthotopic GBM growth with reduced side effects of the chemotherapeutic. Findings from this study indicate that the developed DTX@Ang-EM provide a new strategy for targeted brain drug delivery and GBM therapy.Graphical abstract

Trial working groups for paediatric brain tumours

Abstract Aims Children's brain tumours are the biggest cancer killer in children and young adults. Several recent developments have the potential to change the treatment of brain tumours in children. These include intra-CSF chemotherapy, ultrasound-mediated blood-brain barrier disruption, convection enhanced delivery, polymer delivery systems and electric field therapy, as well as intra-arterial and intra-nasal chemotherapy. To date, there have been very few clinical trials to evaluate any of these. The science and technology underlying these developments is not traditionally embedded within the standard paediatric neuro-oncology network. In addition, custom-built hardware, novel surgical procedures and, in some cases, the testing and licensing of implantable devices, add difficulty at the regulatory level. Method The authors participated in an international workshop funded by the charity Children with Cancer UK in 2016, where different experimental techniques aimed at optimising CNS drug delivery were discussed. Following this workshop and two subsequent workshops run by the CBTDDC (Children’s Brain Tumour Drug Delivery Consortium) in 2018 and 2020, the CBTDDC and the recently developed ITCC (Innovative Therapies for Children with Cancer) brain tumour group started working together to set up a new initiative. Called the ‘Clinical Trials Working Group for Central Nervous System Drug Delivery’, this aims to accelerate clinical trials to assess the safety and effectiveness of drug delivery devices for the treatment of paediatric brain tumours. On March 1st, 2021, CBTDDC with guest chair, Mr Kristian Aquilina (Consultant Paediatric Neurosurgeon at Great Ormond Street Hospital), hosted the first virtual meeting of this group. Results We have assembled a prestigious steering group, comprising international researchers and clinicians with expertise in diverse aspects of translational and clinical research in CNS drug delivery. At our first group meeting on March 1st, 2021, 38 leading brain tumour research scientists and clinicians from the UK, EU and US tackled the challenges head-on, with commitment and a driving passion to identify and move forwards with the most effective ways of translating drug delivery modalities into clinical trials. Attendees were split into three break-out sessions based on distinct drug delivery systems, and lots of insightful comments were collated. Conclusion The ideas generated during the 1st March meeting will help form the basis of a CBTDDC ‘Clinical Trials’ workshop in the autumn of 2021. In particular, there was an agreed consensus that a key objective will be the creation of a ‘Roadmap’ document for pre-clinical to clinical translation which would be shared with the paediatric neuro-oncology research community. CBTDDC look forward to working with steering group as we act on their recommendations to address the current challenges faced by translational drug delivery research. We present this abstract to the BNOS Annual 2021 Meeting to raise awareness of this initiative with the large number of relevant stakeholders who will be attending the event.

CLRM-08. TRIAL WORKING GROUPS FOR PAEDIATRIC BRAIN TUMOURS

INTRODUCTIONBrain tumours are the biggest cancer killer in children and young adults. Several recent developments have the potential to change the outlook for these children, including intra-CSF chemotherapy, ultrasound-mediated blood-brain barrier disruption, convection enhanced delivery, polymer delivery systems, electric field therapy, and intra-arterial and intra-nasal chemotherapy. To date, there have been very few clinical trials to evaluate these. In addition, custom-built hardware, novel surgical procedures and the testing and licensing of implantable devices add difficulty at the regulatory level.METHODSThe authors participated in an international workshop funded by the charity Children with Cancer UK in 2016, where different experimental techniques aimed at optimising CNS drug delivery were discussed. Following this and two subsequent workshops run by the CBTDDC (Children’s Brain Tumour Drug Delivery Consortium), the CBTDDC and the ITCC (Innovative Therapies for Children with Cancer) brain tumour group launched the ‘Clinical Trials Working Group for Central Nervous System Drug Delivery’. This aims to accelerate clinical trials to assess the safety and effectiveness of drug delivery devices for the treatment of paediatric brain tumours.RESULTSOn 1 March, 2021, CBTDDC and Mr Kristian Aquilina (Consultant Paediatric Neurosurgeon at Great Ormond Street Hospital) hosted the first steering group meeting, comprising 38 leading brain tumour research scientists and clinicians from the UK, EU and US.CONCLUSIONThe ideas generated during the March meeting are driving the agenda for a Clinical Trials Workshop that will be held in the autumn of 2021. In particular, there was agreed consensus that a ‘Roadmap’ document for pre-clinical to clinical translation needs to be created and shared with the paediatric neuro-oncology research community. We present this abstract to the CNS Clinical Trials Meeting to raise awareness of this initiative with the large number of relevant stakeholders who will be attending the event.

Emerging Nano-Carrier Strategies for Brain Tumor Drug Delivery and Considerations for Clinical Translation.

Treatment of brain tumors is challenging since the blood–brain tumor barrier prevents chemotherapy drugs from reaching the tumor site in sufficient concentrations. Nanomedicines have great potential for therapy of brain disorders but are still uncommon in clinical use despite decades of research and development. Here, we provide an update on nano-carrier strategies for improving brain drug delivery for treatment of brain tumors, focusing on liposomes, extracellular vesicles and biomimetic strategies as the most clinically feasible strategies. Finally, we describe the obstacles in translation of these technologies including pre-clinical models, analytical methods and regulatory issues.

Exosomes and biomimetic nanovesicles-mediated anti-glioblastoma therapy: A head-to-head comparison

Exosomes (Exos) are promising vehicles for brain drug delivery due to nanosize and the ability to breach the blood–brain barrier (BBB). But the low yield of natural exosomes limits its application for nanomedicine. The generation of bioinspired nanovesicles (BNVs) that mimicking Exos is attractive, but there is a lack of comparative evaluation of Exos and BNVs. Here, we perform the first head-to-head comparison study of Exos and BNVs for brain tumor drug delivery. We show that BNVs derived from brain-derived endothelial cells are competent alternative nanocarrier to natural exosomes. The drug-loading capacity of Exos and BNVs are similar, but the yield of BNVs is substantially higher (500-fold) than Exos. Doxorubicin (DOX)-loaded BNVs (BNV/DOX) and DOX-loaded Exos (Exo/DOX) showed similar pharmacokinetic profiles and prolonged circulation od DOX. Despite inconsistent mechanisms, BNV/DOX can across the BBB, and exhibit suppression effects similar to Exo/DOX on the progress of glioblastoma (GBM) in zebrafish and in vivo subcutaneous and orthotopic xenografts mice models, with minimal systemic toxicity. Findings from this head-to-head comparison study indicate that autologous BNVs is a effective alternative of Exos for brain tumor nanomedicine.

EPCT-08. TRIAL WORKING GROUPS FOR PAEDIATRIC BRAIN TUMOURS

IntroductionBrain tumours are the biggest cancer killer in children and young adults. Several recent developments have the potential to change the treatment of brain tumours in children. These include ultrasound-mediated blood-brain barrier disruption, convection enhanced delivery, polymer delivery systems and electric field therapy, as well as intra-arterial, intra-CSF and intra-nasal chemotherapy. To date, there have been very few clinical trials to evaluate any of these. The science and technology underlying these developments is not traditionally embedded within the standard paediatric neuro-oncology network. In addition, custom-built hardware, novel surgical procedures and, in some cases, the testing and licensing of implantable devices, add difficulty at the regulatory level. MethodsThe authors participated in an international workshop funded by the charity Children with Cancer UK in 2016, where different experimental techniques aimed at optimising CNS drug delivery were discussed. Following this workshop and two subsequent workshops run by the CBTDDC (Children’s Brain Tumour Drug Delivery Consortium) in 2018 and 2020, the CBTDDC and the recently developed ITCC (Innovative Therapies for Children with Cancer) brain tumour group started working together to set up a new initiative. This aims to develop CNS-delivery-focused trial working groups for paediatric brain tumours. ResultsWe have assembled a prestigious steering group, comprising international researchers and clinicians with expertise in diverse aspects of translational and clinical research in CNS drug delivery. At our first group meeting in March, participants will discuss the most effective ways of translating the emerging drug delivery modalities into clinical trials. Prioritised actions will be taken forward and the group will reconvene to discuss developments and next steps at a workshop in the Autumn. ConclusionWe present this abstract to the SNO Paediatric conference to raise awareness of this initiative with the large number of relevant stakeholders who will be attending the event.

Thermodynamic study on solubility of brain tumor drug in supercritical solvent: Temozolomide case study

One of the effective medications for Glioblastoma Multiforme is Temozolomide (TMZ) which is taken as a treatment for some brain cancers. With respect to the importance of this drug in cancer therapy, the solubility of this medicine was analyzed under various ranges of pressure and temperature in supercritical carbon dioxide (SC-CO2) to evaluate the possibility of drug micronization for reducing its undesired side effects. The measurements were conducted using gravimetric method and revealed that the solubility of the drug is between 4.30 × 10−4 to 5.28 × 10−3 based on mole fraction. The results demonstrated the strong dependency of the TMZ solubility to pressure and temperature, while the effect of pressure is more profound at higher temperatures. Besides, the calculated solubility data was correlated employing five popular semi-empirical density-based correlations including Bartle et al., Chrastil, Kumar and Johnston, Mendez-Santiago-Teja, and Garlapati & Madras models. The obtained outcomes illustrated that among the tested models, KJ led to the best correlative ability with average absolute relative deviation percent (AARD %) of 8.39%, while Garlapati and Madras led to the worst modeling results with AARD % of 15.20%.

PD-1 Inhibitors: Do they have a Future in the Treatment of Glioblastoma?

Glioblastoma (WHO grade IV glioma) is the most common malignant primary brain tumor in adults. Survival has remained largely static for decades, despite significant efforts to develop new effective therapies. Immunotherapy and especially immune checkpoint inhibitors and programmed cell death (PD)-1/PD-L1 inhibitors have transformed the landscape of cancer treatment and improved patient survival in a number of different cancer types. With the exception of few select cases (e.g., patients with Lynch syndrome) the neuro-oncology community is still awaiting evidence that PD-1 blockade can lead to meaningful clinical benefit in glioblastoma. This lack of progress in the field is likely to be due to multiple reasons, including inherent challenges in brain tumor drug development, the blood-brain barrier, the unique immune environment in the brain, the impact of corticosteroids, as well as inter- and intratumoral heterogeneity. Here we critically review the clinical literature, address the unique aspects of glioma immunobiology and potential immunobiological barriers to progress, and contextualize new approaches to increase the efficacy of PD-1/PD-L1 inhibitors in glioblastoma that may identify gaps and testable relevant hypotheses for future basic and clinical research and to provide a novel perspective to further stimulate preclinical and clinical research to ultimately help patients with glioma, including glioblastoma, which is arguably one of the greatest areas of unmet need in cancer. Moving forward, we need to build on our existing knowledge by conducting further fundamental glioma immunobiology research in parallel with innovative and methodologically sound clinical trials.

A comparative study of brain tumor cells from different age and anatomical locations using 3D biomimetic hydrogels

Brain tumors exhibit vast genotypic and phenotypic diversity depending on patient age and anatomical location. Hydrogels hold great promise as 3D in vitro models for studying brain tumor biology and drug screening, yet previous studies were limited to adult glioblastoma cells, and most studies used immortalized cell lines. Here we report a hydrogel platform that supports the proliferation and invasion of patient-derived brain tumor cell cultures (PDCs) isolated from different patient age groups and anatomical locations. Hydrogel stiffness was tuned by varying poly(ethylene-glycol) concentration. Cell adhesive peptide (CGRDS), hyaluronic acid, and MMP-cleavable crosslinkers were incorporated to facilitate cell adhesion and cell-mediated degradation. Three PDC lines were compared including adult glioblastoma cells (aGBM), pediatric glioblastoma cells (pGBM), and diffuse pontine intrinsic glioma (DIPG). A commonly used immortalized adult glioblastoma cell line U87 was included as a control. PDCs displayed stiffness-dependent behavior, with 40 Pa hydrogel promoting faster tumor proliferation and invasion. Adult GBM cells exhibited faster proliferation than pediatric GBM, and DIPG showed slowest proliferation. These results suggest both patient age and tumor location affects brain tumor behaviors. Adult GBM PDCs also exhibited very different cell proliferation and morphology from U87. The hydrogel reported here can provide a useful tool for future studies to better understand how age and anatomical locations impacts brain tumor progression using 3D in vitro models.