ABSTRACT
Many tumors produce platelet-derived growth factor (PDGF)-DD, which promotes cellular proliferation, epithelial-mesenchymal transition, stromal reaction, and angiogenesis through autocrine and paracrine PDGFRß signaling. By screening a secretome library, we found that the human immunoreceptor NKp44, encoded by NCR2 and expressed on natural killer (NK) cells and innate lymphoid cells, recognizes PDGF-DD. PDGF-DD engagement of NKp44 triggered NK cell secretion of interferon gamma (IFN)-γ and tumor necrosis factor alpha (TNF-α) that induced tumor cell growth arrest. A distinctive transcriptional signature of PDGF-DD-induced cytokines and the downregulation of tumor cell-cycle genes correlated with NCR2 expression and greater survival in glioblastoma. NKp44 expression in mouse NK cells controlled the dissemination of tumors expressing PDGF-DD more effectively than control mice, an effect enhanced by blockade of the inhibitory receptor CD96 or CpG-oligonucleotide treatment. Thus, while cancer cell production of PDGF-DD supports tumor growth and stromal reaction, it concomitantly activates innate immune responses to tumor expansion.
Subject(s)
Brain Neoplasms/immunology , Cell Cycle Checkpoints , Glioblastoma/immunology , Killer Cells, Natural/immunology , Platelet-Derived Growth Factor/metabolism , Animals , Brain Neoplasms/pathology , CHO Cells , Cells, Cultured , Cricetinae , Cricetulus , Female , Glioblastoma/pathology , Humans , Immunity, Innate , Interferon-gamma/metabolism , MCF-7 Cells , Male , Mice , Mice, Inbred C57BL , Natural Cytotoxicity Triggering Receptor 2/metabolism , Tumor Necrosis Factor-alpha/metabolismABSTRACT
To study the spatial interactions among cancer and non-cancer cells1, we here examined a cohort of 131 tumour sections from 78 cases across 6 cancer types by Visium spatial transcriptomics (ST). This was combined with 48 matched single-nucleus RNA sequencing samples and 22 matched co-detection by indexing (CODEX) samples. To describe tumour structures and habitats, we defined 'tumour microregions' as spatially distinct cancer cell clusters separated by stromal components. They varied in size and density among cancer types, with the largest microregions observed in metastatic samples. We further grouped microregions with shared genetic alterations into 'spatial subclones'. Thirty five tumour sections exhibited subclonal structures. Spatial subclones with distinct copy number variations and mutations displayed differential oncogenic activities. We identified increased metabolic activity at the centre and increased antigen presentation along the leading edges of microregions. We also observed variable T cell infiltrations within microregions and macrophages predominantly residing at tumour boundaries. We reconstructed 3D tumour structures by co-registering 48 serial ST sections from 16 samples, which provided insights into the spatial organization and heterogeneity of tumours. Additionally, using an unsupervised deep-learning algorithm and integrating ST and CODEX data, we identified both immune hot and cold neighbourhoods and enhanced immune exhaustion markers surrounding the 3D subclones. These findings contribute to the understanding of spatial tumour evolution through interactions with the local microenvironment in 2D and 3D space, providing valuable insights into tumour biology.
Subject(s)
DNA Copy Number Variations , Neoplasms , Tumor Microenvironment , Humans , Neoplasms/genetics , Neoplasms/pathology , Neoplasms/immunology , DNA Copy Number Variations/genetics , Deep Learning , Transcriptome , Mutation , Macrophages/metabolism , Macrophages/immunology , Antigen Presentation , T-Lymphocytes/immunology , T-Lymphocytes/metabolism , Clone Cells/metabolism , Clone Cells/pathologyABSTRACT
Chromatin accessibility is essential in regulating gene expression and cellular identity, and alterations in accessibility have been implicated in driving cancer initiation, progression and metastasis1-4. Although the genetic contributions to oncogenic transitions have been investigated, epigenetic drivers remain less understood. Here we constructed a pan-cancer epigenetic and transcriptomic atlas using single-nucleus chromatin accessibility data (using single-nucleus assay for transposase-accessible chromatin) from 225 samples and matched single-cell or single-nucleus RNA-sequencing expression data from 206 samples. With over 1 million cells from each platform analysed through the enrichment of accessible chromatin regions, transcription factor motifs and regulons, we identified epigenetic drivers associated with cancer transitions. Some epigenetic drivers appeared in multiple cancers (for example, regulatory regions of ABCC1 and VEGFA; GATA6 and FOX-family motifs), whereas others were cancer specific (for example, regulatory regions of FGF19, ASAP2 and EN1, and the PBX3 motif). Among epigenetically altered pathways, TP53, hypoxia and TNF signalling were linked to cancer initiation, whereas oestrogen response, epithelial-mesenchymal transition and apical junction were tied to metastatic transition. Furthermore, we revealed a marked correlation between enhancer accessibility and gene expression and uncovered cooperation between epigenetic and genetic drivers. This atlas provides a foundation for further investigation of epigenetic dynamics in cancer transitions.
Subject(s)
Epigenesis, Genetic , Gene Expression Regulation, Neoplastic , Neoplasms , Humans , Cell Hypoxia , Cell Nucleus , Chromatin/genetics , Chromatin/metabolism , Enhancer Elements, Genetic/genetics , Epigenesis, Genetic/genetics , Epithelial-Mesenchymal Transition , Estrogens/metabolism , Gene Expression Profiling , GTPase-Activating Proteins/metabolism , Neoplasm Metastasis , Neoplasms/classification , Neoplasms/genetics , Neoplasms/pathology , Regulatory Sequences, Nucleic Acid/genetics , Single-Cell Analysis , Transcription Factors/metabolismABSTRACT
Integrating multimodal neuro- and nanotechnology-enabled precision immunotherapies with extant systemic immunotherapies may finally provide a significant breakthrough for combatting glioblastoma (GBM). The potency of this approach lies in its ability to train the immune system to efficiently identify and eradicate cancer cells, thereby creating anti-tumor immune memory while minimizing multi-mechanistic immune suppression. A critical aspect of these therapies is the controlled, spatiotemporal delivery of structurally defined nanotherapeutics into the GBM tumor microenvironment (TME). Architectures such as spherical nucleic acids or poly(beta-amino ester)/dendrimer-based nanoparticles have shown promising results in preclinical models due to their multivalency and abilities to activate antigen-presenting cells and prime antigen-specific T cells. These nanostructures also permit systematic variation to optimize their distribution, TME accumulation, cellular uptake, and overall immunostimulatory effects. Delving deeper into the relationships between nanotherapeutic structures and their performance will accelerate nano-drug development and pave the way for the rapid clinical translation of advanced nanomedicines. In addition, the efficacy of nanotechnology-based immunotherapies may be enhanced when integrated with emerging precision surgical techniques, such as laser interstitial thermal therapy, and when combined with systemic immunotherapies, particularly inhibitors of immune-mediated checkpoints and immunosuppressive adenosine signaling. In this perspective, we highlight the potential of emerging treatment modalities, combining advances in biomedical engineering and neurotechnology development with existing immunotherapies to overcome treatment resistance and transform the management of GBM. We conclude with a call to action for researchers to leverage these technologies and accelerate their translation into the clinic.
Subject(s)
Brain Neoplasms , Glioblastoma , Nanoparticles , Nanostructures , Humans , Glioblastoma/pathology , Immunotherapy/methods , Nanoparticles/therapeutic use , Nanoparticles/chemistry , Nanotechnology , Nanostructures/chemistry , Tumor Microenvironment , Brain Neoplasms/pathologyABSTRACT
The ubiquitin ligase anaphase-promoting complex (APC) recruits the coactivator Cdc20 to drive mitosis in cycling cells. However, the nonmitotic functions of Cdc20-APC have remained unexplored. We report that Cdc20-APC plays an essential role in dendrite morphogenesis in postmitotic neurons. Knockdown of Cdc20 in cerebellar slices and in postnatal rats in vivo profoundly impairs the formation of granule neuron dendrite arbors in the cerebellar cortex. Remarkably, Cdc20 is enriched at the centrosome in neurons, and the centrosomal localization is critical for Cdc20-dependent dendrite development. We also find that the centrosome-associated protein histone deacetylase 6 (HDAC6) promotes the polyubiquitination of Cdc20, stimulates the activity of centrosomal Cdc20-APC, and drives the differentiation of dendrites. These findings define a postmitotic function for Cdc20-APC in the morphogenesis of dendrites in the mammalian brain. The identification of a centrosomal Cdc20-APC ubiquitin signaling pathway holds important implications for diverse biological processes, including neuronal connectivity and plasticity.
Subject(s)
Centrosome/metabolism , Cerebellar Cortex/cytology , Dendrites/metabolism , Neurons/cytology , Signal Transduction , Anaphase-Promoting Complex-Cyclosome , Animals , Cdc20 Proteins , Cell Cycle Proteins/metabolism , In Vitro Techniques , Inhibitor of Differentiation Protein 1/metabolism , Neurons/metabolism , Rats , Rats, Sprague-Dawley , Ubiquitin-Protein Ligase Complexes/metabolismABSTRACT
With the application of high throughput sequencing technologies at single-cell resolution, studies of the tumor microenvironment in glioblastoma, one of the most aggressive and invasive of all cancers, have revealed immense cellular and tissue heterogeneity. A unique extracellular scaffold system adapts to and supports progressive infiltration and migration of tumor cells, which is characterized by altered composition, effector delivery, and mechanical properties. The spatiotemporal interactions between malignant and immune cells generate an immunosuppressive microenvironment, contributing to the failure of effective anti-tumor immune attack. Among the heterogeneous tumor cell subpopulations of glioblastoma, glioma stem cells (GSCs), which exhibit tumorigenic properties and strong invasive capacity, are critical for tumor growth and are believed to contribute to therapeutic resistance and tumor recurrence. Here we discuss the role of extracellular matrix and immune cell populations, major components of the tumor ecosystem in glioblastoma, as well as signaling pathways that regulate GSC maintenance and invasion. We also highlight emerging advances in therapeutic targeting of these components.
Subject(s)
Brain Neoplasms , Glioblastoma , Glioma , Humans , Glioblastoma/drug therapy , Ecosystem , Glioma/pathology , Tumor Microenvironment , Extracellular Matrix/metabolism , Neoplastic Stem Cells/pathology , Brain Neoplasms/drug therapy , Cell Line, TumorABSTRACT
PURPOSE: Glioblastoma (GBM) is the most common and aggressive malignant glioma, with an overall median survival of less than two years. The ability to predict survival before treatment in GBM patients would lead to improved disease management, clinical trial enrollment, and patient care. METHODS: GBM patients (N = 133, mean age 60.8 years, median survival 14.1 months, 57.9% male) were retrospectively recruited from the neurosurgery brain tumor service at Washington University Medical Center. All patients completed structural neuroimaging and resting state functional MRI (RS-fMRI) before surgery. Demographics, measures of cortical thickness (CT), and resting state functional network connectivity (FC) were used to train a deep neural network to classify patients based on survival (< 1y, 1-2y, >2y). Permutation feature importance identified the strongest predictors of survival based on the trained models. RESULTS: The models achieved a combined cross-validation and hold out accuracy of 90.6% in classifying survival (< 1y, 1-2y, >2y). The strongest demographic predictors were age at diagnosis and sex. The strongest CT predictors of survival included the superior temporal sulcus, parahippocampal gyrus, pericalcarine, pars triangularis, and middle temporal regions. The strongest FC features primarily involved dorsal and inferior somatomotor, visual, and cingulo-opercular networks. CONCLUSION: We demonstrate that machine learning can accurately classify survival in GBM patients based on multimodal neuroimaging before any surgical or medical intervention. These results were achieved without information regarding presentation symptoms, treatments, postsurgical outcomes, or tumor genomic information. Our results suggest GBMs have a global effect on the brain's structural and functional organization, which is predictive of survival.
Subject(s)
Glioblastoma , Humans , Male , Middle Aged , Female , Glioblastoma/diagnostic imaging , Glioblastoma/therapy , Retrospective Studies , Magnetic Resonance Imaging/methods , Neuroimaging , Machine LearningABSTRACT
Many procedures in modern clinical medicine rely on the use of electronic implants in treating conditions that range from acute coronary events to traumatic injury. However, standard permanent electronic hardware acts as a nidus for infection: bacteria form biofilms along percutaneous wires, or seed haematogenously, with the potential to migrate within the body and to provoke immune-mediated pathological tissue reactions. The associated surgical retrieval procedures, meanwhile, subject patients to the distress associated with re-operation and expose them to additional complications. Here, we report materials, device architectures, integration strategies, and in vivo demonstrations in rats of implantable, multifunctional silicon sensors for the brain, for which all of the constituent materials naturally resorb via hydrolysis and/or metabolic action, eliminating the need for extraction. Continuous monitoring of intracranial pressure and temperature illustrates functionality essential to the treatment of traumatic brain injury; the measurement performance of our resorbable devices compares favourably with that of non-resorbable clinical standards. In our experiments, insulated percutaneous wires connect to an externally mounted, miniaturized wireless potentiostat for data transmission. In a separate set-up, we connect a sensor to an implanted (but only partially resorbable) data-communication system, proving the principle that there is no need for any percutaneous wiring. The devices can be adapted to sense fluid flow, motion, pH or thermal characteristics, in formats that are compatible with the body's abdomen and extremities, as well as the deep brain, suggesting that the sensors might meet many needs in clinical medicine.
Subject(s)
Absorbable Implants , Brain/metabolism , Electronics/instrumentation , Monitoring, Physiologic/instrumentation , Prostheses and Implants , Silicon , Absorbable Implants/adverse effects , Administration, Cutaneous , Animals , Body Temperature , Brain/surgery , Equipment Design , Hydrolysis , Male , Monitoring, Physiologic/adverse effects , Organ Specificity , Pressure , Prostheses and Implants/adverse effects , Rats , Rats, Inbred Lew , Telemetry/instrumentation , Wireless Technology/instrumentationABSTRACT
OBJECTIVE: For patients with surgically accessible solitary metastases or oligometastatic disease, treatment often involves resection followed by postoperative stereotactic radiosurgery (SRS). This strategy has several potential drawbacks, including irregular target delineation for SRS and potential tumor "seeding" away from the resection cavity during surgery. A neoadjuvant (preoperative) approach to radiation therapy avoids these limitations and offers improved patient convenience. This study assessed the efficacy of neoadjuvant SRS as a new treatment paradigm for patients with brain metastases. METHODS: A retrospective review was performed at a single institution to identify patients who had undergone neoadjuvant SRS (specifically, Gamma Knife radiosurgery) followed by resection of a brain metastasis. Kaplan-Meier survival and log-rank analyses were used to evaluate risks of progression and death. Assessments were made of local recurrence and leptomeningeal spread. Additionally, an analysis of the contemporary literature of postoperative and neoadjuvant SRS for metastatic disease was performed. RESULTS: Twenty-four patients who had undergone neoadjuvant SRS followed by resection of a brain metastasis were identified in the single-institution cohort. The median age was 64 years (range 32-84 years), and the median follow-up time was 16.5 months (range 1 month to 5.7 years). The median radiation dose was 17 Gy prescribed to the 50% isodose. Rates of local disease control were 100% at 6 months, 87.6% at 12 months, and 73.5% at 24 months. In 4 patients who had local treatment failure, salvage therapy included repeat resection, laser interstitial thermal therapy, or repeat SRS. One hundred thirty patients (including the current cohort) were identified in the literature who had been treated with neoadjuvant SRS prior to resection. Overall rates of local control at 1 year after neoadjuvant SRS treatment ranged from 49% to 91%, and rates of leptomeningeal dissemination from 0% to 16%. In comparison, rates of local control 1 year after postoperative SRS ranged from 27% to 91%, with 7% to 28% developing leptomeningeal disease. CONCLUSIONS: Neoadjuvant SRS for the treatment of brain metastases is a novel approach that mitigates the shortcomings of postoperative SRS. While additional prospective studies are needed, the current study of 130 patients including the summary of 106 previously published cases supports the safety and potential efficacy of preoperative SRS with potential for improved outcomes compared with postoperative SRS.
Subject(s)
Brain Neoplasms , Meningeal Neoplasms , Radiosurgery , Humans , Adult , Middle Aged , Aged , Aged, 80 and over , Radiosurgery/adverse effects , Neoadjuvant Therapy/adverse effects , Brain Neoplasms/surgery , Meningeal Neoplasms/surgery , Salvage Therapy , Retrospective Studies , Treatment OutcomeABSTRACT
The blood-brain and blood-tumor barriers represent highly specialized structures responsible for tight regulation of molecular transit into the central nervous system. Under normal circumstances, the relative impermeability of the blood-brain barrier (BBB) protects the brain from circulating toxins and contributes to a brain microenvironment necessary for optimal neuronal function. However, in the context of tumors and other diseases of central nervous system, the BBB and the more recently appreciated blood-tumor barrier (BTB) represent barriers that prevent effective drug delivery. Overcoming both barriers to optimize treatment of central nervous system diseases remains the subject of intense scientific investigation. Although many newer technologies have been developed to overcome these barriers, thermal therapy, which dates back to the 1890 s, has been known to disrupt the BBB since at least the early 1980s. Recently, as a result of several technological advances, laser interstitial thermal therapy (LITT), a method of delivering targeted thermal therapy, has gained widespread use as a surgical technique to ablate brain tumors. In addition, accumulating evidence indicates that laser ablation may also increase local BBB/BTB permeability after treatment. We herein review the structure and function of the BBB and BTB and the impact of thermal injury, including LITT, on barrier function.
Subject(s)
Blood-Brain Barrier , Brain Neoplasms , Hyperthermia, Induced , Biological Transport , Brain Neoplasms/blood supply , Brain Neoplasms/therapy , Drug Delivery Systems , Humans , Tumor MicroenvironmentABSTRACT
PURPOSE: Endoscopic transsphenoidal surgery (ETSS) is a well-established treatment for patients with nonfunctioning pituitary adenomas (NFPAs). Data on the rates of pituitary dysfunction and recovery in a large cohort of NFPA patients undergoing ETSS and the predictors of endocrine function before and after ETSS are scarce. This study is purposed to analyze the comprehensive changes in hormonal function and identify factors that predict recovery or worsening of hormonal axes following ETSS for NFPA. METHODS: A retrospective review of 601 consecutive patients who underwent ETSS between 2010 and 2018 at one institution was performed. Recovery or development of new hypopituitarism was analyzed in 209 NFPA patients who underwent ETSS. RESULTS: Patients with preoperative endocrine deficits (59.8%) in one or more pituitary axes had larger tumor volumes (P = 0.001) than those without preoperative deficits. Recovery of preoperative pituitary deficit occurred in all four axes, with overall mean recovery of 29.7%. The cortisol axis showed the highest recovery whereas the thyroid axis showed the lowest, with 1-year cumulative recovery rates of 44.3% and 6.1%, respectively. Postoperative hypopituitarism occurred overall in 17.2%, most frequently in the thyroid axis (24.3%, 27/111) and least frequently in the cortisol axis (9.7%, 16/165). Axis-specific predictors of post-operative recovery and deficiency were identified. CONCLUSIONS: Dynamic alterations in pituitary hormones were observed in a proportion of patients following ETSS in NFPA patients. Postoperative endocrine vulnerability, recovery, and factors that predicted recovery or loss of endocrine function depended on the hormonal system, necessitating an axis-specific surveillance strategy postoperatively.
Subject(s)
Adenoma/surgery , Adrenal Insufficiency/metabolism , Hypogonadism/metabolism , Hypopituitarism/metabolism , Hypothyroidism/metabolism , Pituitary Neoplasms/surgery , Recovery of Function , Adenoma/complications , Adenoma/metabolism , Adrenal Insufficiency/etiology , Adrenocorticotropic Hormone/metabolism , Aged , Estradiol/metabolism , Female , Follicle Stimulating Hormone/metabolism , Human Growth Hormone/deficiency , Human Growth Hormone/metabolism , Humans , Hydrocortisone/metabolism , Hyperprolactinemia/etiology , Hyperprolactinemia/metabolism , Hypogonadism/etiology , Hypopituitarism/etiology , Hypothalamo-Hypophyseal System , Hypothyroidism/etiology , Insulin-Like Growth Factor I/metabolism , Luteinizing Hormone/metabolism , Male , Middle Aged , Neuroendoscopy , Pituitary Neoplasms/complications , Pituitary Neoplasms/metabolism , Pituitary-Adrenal Function Tests , Pituitary-Adrenal System , Prolactin/metabolism , Sphenoid Bone , Testosterone/metabolism , Thyrotropin/metabolism , Thyroxine/metabolism , Treatment OutcomeABSTRACT
Laser interstitial thermal therapy (LITT) is a minimally invasive and cytoreductive neurosurgical technique that has gained significant momentum in the last decade. Several technological enhancements such as MRI thermometry and improved laser probe design have enabled feasibility and improved the safety of LITT procedures. Numerous reports have been published describing the treatment of lesions ranging from tumors to epileptogenic foci, but the indications for LITT continue to evolve. We describe the general physical and biological concepts underlying LITT, clinical workflow, and established and emerging indications.
Subject(s)
Ablation Techniques/methods , Brain Neoplasms/surgery , Epilepsy/surgery , Laser Therapy/methods , Ablation Techniques/instrumentation , Humans , Magnetic Resonance Imaging , Neurosurgical ProceduresABSTRACT
Huntington's disease (HD) is a fatal neurodegenerative disorder caused by an abnormal expansion of polyglutamine repeats in the huntingtin protein (Htt). Transcriptional dysregulation is an early event in the course of HD progression and is thought to contribute to disease pathogenesis, but how mutant Htt causes transcriptional alterations and subsequent cell death in neurons is not well understood. RNA-Seq analysis revealed that expression of a mutant Htt fragment in primary cortical neurons leads to robust gene expression changes before neuronal death. Basic helix-loop-helix transcription factor Twist1, which is essential for embryogenesis and is normally expressed at low levels in mature neurons, was substantially up-regulated in mutant Htt-expressing neurons in culture and in the brains of HD mouse models. Knockdown of Twist1 by RNAi in mutant Htt-expressing primary cortical neurons reversed the altered expression of a subset of genes involved in neuronal function and, importantly, abrogated neurotoxicity. Using brain-derived neurotrophic factor (Bdnf), which is known to be involved in HD pathogenesis, as a model gene, we found that Twist1 knockdown could reverse mutant Htt-induced DNA hypermethylation at the Bdnf regulatory region and reactivate Bdnf expression. Together, these results suggest that Twist1 is an important upstream mediator of mutant Htt-induced neuronal death and may in part operate through epigenetic mechanisms.
Subject(s)
Epigenesis, Genetic , Huntingtin Protein/genetics , Huntington Disease/genetics , Twist-Related Protein 1/genetics , Animals , Brain-Derived Neurotrophic Factor/genetics , Brain-Derived Neurotrophic Factor/metabolism , Cells, Cultured , DNA Methylation , Female , Gene Regulatory Networks , Humans , Huntingtin Protein/metabolism , Huntington Disease/metabolism , Male , Mice , Mutation , Neurons/metabolism , Transcriptional Activation , Twist-Related Protein 1/metabolismABSTRACT
Accumulating evidence suggests cancer cells exhibit a dependency on metabolic pathways regulated by nicotinamide adenine dinucleotide (NAD+). Nevertheless, how the regulation of this metabolic cofactor interfaces with signal transduction networks remains poorly understood in glioblastoma. Here, we report nicotinamide phosphoribosyltransferase (NAMPT), the rate-limiting step in NAD+ synthesis, is highly expressed in glioblastoma tumors and patient-derived glioblastoma stem-like cells (GSCs). High NAMPT expression in tumors correlates with decreased patient survival. Pharmacological and genetic inhibition of NAMPT decreased NAD+ levels and GSC self-renewal capacity, and NAMPT knockdown inhibited the in vivo tumorigenicity of GSCs. Regulatory network analysis of RNA sequencing data using GSCs treated with NAMPT inhibitor identified transcription factor E2F2 as the center of a transcriptional hub in the NAD+-dependent network. Accordingly, we demonstrate E2F2 is required for GSC self-renewal. Downstream, E2F2 drives the transcription of members of the inhibitor of differentiation (ID) helix-loop-helix gene family. Finally, we find NAMPT mediates GSC radiation resistance. The identification of a NAMPT-E2F2-ID axis establishes a link between NAD+ metabolism and a self-renewal transcriptional program in glioblastoma, with therapeutic implications for this formidable cancer.
Subject(s)
Brain Neoplasms/metabolism , Cytokines/genetics , Glioblastoma/metabolism , NAD/biosynthesis , Nicotinamide Phosphoribosyltransferase/genetics , Radiation Tolerance , Transcription, Genetic , Animals , Antineoplastic Agents/pharmacology , Brain/pathology , Brain Neoplasms/radiotherapy , Cell Line, Tumor , Cell Nucleus/metabolism , Cell Proliferation , Gene Expression Regulation, Neoplastic , Glioblastoma/radiotherapy , Humans , Mice , Mutation , Neoplasm Transplantation , RNA Interference , Signal Transduction/drug effects , Stem Cells/cytologyABSTRACT
Resting-state functional MRI (rs-fMRI) is a well-established method for studying intrinsic connectivity and mapping the topography of functional networks in the human brain. In the clinical setting, rs-fMRI has been used to define functional topography, typically language and motor systems, in the context of preoperative planning for neurosurgery. Intraoperative mapping of critical speech and motor areas with electrocortical stimulation (ECS) remains standard practice, but preoperative noninvasive mapping has the potential to reduce operative time and provide functional localization when awake mapping is not feasible. Task-based fMRI has historically been used for this purpose, but it can be limited by the young age of the patient, cognitive impairment, poor cooperation, and need for sedation. Resting-state fMRI allows reliable analysis of all functional networks with a single study and is inherently independent of factors affecting task performance. In this review, the authors provide a summary of the theory and methods for resting-state network mapping. They provide case examples illustrating clinical implementation and discuss limitations of rs-fMRI and review available data regarding performance in comparison to ECS. Finally, they discuss novel opportunities for future clinical applications and prospects for rs-fMRI beyond mapping of regions to avoid during surgery but, instead, as a tool to guide novel network-based therapies.
Subject(s)
Brain Mapping/methods , Magnetic Resonance Imaging/methods , Nerve Net/diagnostic imaging , Adult , Brain Neoplasms/diagnostic imaging , Brain Neoplasms/surgery , Connectome/methods , Electric Stimulation , False Negative Reactions , False Positive Reactions , Forecasting , Frontal Lobe/diagnostic imaging , Frontal Lobe/surgery , Glioblastoma/diagnostic imaging , Glioblastoma/surgery , Humans , Incidental Findings , Male , Oligodendroglioma/diagnostic imaging , Oligodendroglioma/surgery , Temporal Lobe/diagnostic imaging , Temporal Lobe/surgery , Young AdultABSTRACT
Transient receptor potential (TRP) channels have been implicated as sensors of diverse stimuli in mature neurons. However, developmental roles for TRP channels in the establishment of neuronal connectivity remain largely unexplored. Here, we identify an essential function for TRPC5, a member of the canonical TRP subfamily, in the regulation of dendrite patterning in the mammalian brain. Strikingly, TRPC5 knockout mice harbor long, highly branched granule neuron dendrites with impaired dendritic claw differentiation in the cerebellar cortex. In vivo RNAi analyses suggest that TRPC5 regulates dendrite morphogenesis in the cerebellar cortex in a cell-autonomous manner. Correlating with impaired dendrite patterning in the cerebellar cortex, behavioral analyses reveal that TRPC5 knockout mice have deficits in gait and motor coordination. Finally, we uncover the molecular basis of TRPC5's function in dendrite patterning. We identify the major protein kinase calcium/calmodulin-dependent kinase II ß (CaMKIIß) as a critical effector of TRPC5 function in neurons. Remarkably, TRPC5 forms a complex specifically with CaMKIIß, but not the closely related kinase CaMKIIα, and thereby induces the CaMKIIß-dependent phosphorylation of the ubiquitin ligase Cdc20-APC at the centrosome. Accordingly, centrosomal CaMKIIß signaling mediates the ability of TRPC5 to regulate dendrite morphogenesis in neurons. Our findings define a novel function for TRPC5 that couples calcium signaling to a ubiquitin ligase pathway at the centrosome and thereby orchestrates dendrite patterning and connectivity in the brain.
Subject(s)
Calcium Signaling/genetics , Cerebellar Cortex/cytology , Cerebellar Cortex/growth & development , Dendrites/physiology , TRPC Cation Channels/genetics , TRPC Cation Channels/metabolism , Animals , Calcium-Calmodulin-Dependent Protein Kinase Type 2/metabolism , Cells, Cultured , Centrosome/metabolism , Gene Knockout Techniques , Male , Mice , RatsABSTRACT
Disulfiram has shown promising activity including proteasome inhibitory properties and synergy with temozolomide in preclinical glioblastoma (GBM) models. In a phase I study for newly diagnosed GBM after chemoradiotherapy, we have previously reported our initial dose-escalation results combining disulfiram with adjuvant temozolomide and established the maximum tolerated dose (MTD) as 500 mg per day. Here we report the final results of the phase I study including an additional dose-expansion cohort of disulfiram with concurrent copper. The phase I study consisted of an initial dose-escalation phase of disulfiram 500-1000 mg daily during adjuvant temozolomide, followed by a dose-expansion phase of disulfiram 500 mg daily with copper 2 mg three times daily. Proteasome inhibition was assessed using fluorometric 20S proteasome assay on peripheral blood cell. A total of 18 patients were enrolled: 7 patients received 500 mg disulfiram, 5 patients received 1000 mg disulfiram, and 6 patients received 500 mg disulfiram with copper. Two dose-limiting toxicities occurred with 1000 mg disulfiram. At disulfiram 500 mg with or without copper, only 1 patient (7%) required dose-reduction during the first month of therapy. Addition of copper to disulfiram did not increase toxicity nor proteasome inhibition. The median progression-free survival was 4.5 months (95% CI 0.8-8.2). The median overall survival (OS) was 14.0 months (95% CI 8.3-19.6), and the 2-year OS was 24%. The MTD of disulfiram at 500 mg daily in combination with adjuvant temozolomide was well tolerated by GBM patients, but 1000 mg daily was not. Toxicity and pharmacodynamic effect of disulfiram were similar with or without concurrent copper. The clinical efficacy appeared to be comparable to historical data. Additional clinical trials to combine disulfiram and copper with chemoradiotherapy or to resensitize recurrent GBM to temozolomide are ongoing.
Subject(s)
Antineoplastic Agents/therapeutic use , Brain Neoplasms/drug therapy , Copper/therapeutic use , Disulfiram/therapeutic use , Glioblastoma/drug therapy , Trace Elements/therapeutic use , Adjuvants, Immunologic , Adult , Aged , Cohort Studies , Dose-Response Relationship, Drug , Female , Humans , Male , Maximum Tolerated Dose , Middle Aged , Survival Analysis , Temozolomide/therapeutic use , Young AdultABSTRACT
Meningiomas are among the most common tumors of the adult central nervous system (CNS). They are classified by the World Health Organization into three pathologic grades with increasing severity: grade I are benign with favorable treatment outcomes and low recurrence rates while grade III display malignant behavior and poor progression-free survival. Previous studies have shown that inactivation of NF-2 is the most common genetic event in high-grade meningioma; however, there is dearth of molecular data to distinguish grade II (AM-II) from the even more aggressive grade III (AM-III). As part of a routine diagnostic workup, 19 AM-II and 5 AM-III were submitted for targeted sequencing on a panel of twenty-four genes relevant to CNS tumors. The data generated during the course of clinical care was collected and re-analyzed with the aim of identifying molecular features to distinguish AM-II and AM-III. Our cases contained several well-characterized, potentially actionable mutations, but we did not find any novel, recurrent sequence variants. Copy number variations were common in both AM-II and AM-III; chr22q loss was the most prevalent followed in decreasing frequency by losses of chr1p, chr14q, and chr10. In particular, chr10 loss was noted in 4 of 5 AM-III cases but none of the AM-II cases. This suggests that chr10 loss may serve as a diagnostic and perhaps a prognostic marker to differentiate AM-II from AM-III. If confirmed in larger studies, our finding could further aid the classification of meningioma.
Subject(s)
Meningioma/genetics , Adolescent , Adult , Aged , Child , DNA Copy Number Variations , Female , Humans , Male , Meningioma/pathology , Middle Aged , Point MutationSubject(s)
Brain Neoplasms , Radiosurgery , Humans , Brain Neoplasms/surgery , Brain Neoplasms/secondaryABSTRACT
To investigate the patterns of care and outcomes in patients with craniopharyngioma in the National Cancer Data Base (NCDB). This study included 697 patients (166 pediatric and 531 adult cases) treated for craniopharyngioma between 2004 and 2012 in the NCDB. Adjuvant radiotherapy (RT) was defined if within 6 months of surgery. Limited surgery (LS) was defined as biopsy or subtotal resection. Proportional-hazards models were used to evaluate associations between covariates and overall survival (OS). A time-dependent analysis of RT was performed to account for early deaths after surgery. Median follow-up was 46 months. Overall, 21% of patients received adjuvant RT. Of patients with known surgical extent (n = 195), 71% had LS. Utilization of adjuvant RT increased from 18% in 2004-2007 to 24% in 2008-2012. Patterns of care regarding adjuvant RT or LS were not significantly different between adult and pediatric patients. Tumor size, low comorbidity, and LS were associated with increased utilization of adjuvant RT. The 5-year OS among patients treated with LS, LS+RT, and gross total resection were 75, 85, and 82% (p = 0.02). On multivariate analysis of the 195 patients with known surgical extent, LS+RT was associated with improved OS compared to LS (HR 0.22, 95% CI 0.05-0.99, p = 0.04), but was not significant when early deaths (<2 months from surgery) were removed to adjust for immortal-time bias. Medical practice regarding surgical approach and adjuvant RT are similar for pediatric and adult craniopharyngiomas. Immortal-time bias may confound assessment of OS for adjuvant RT. Prospective studies comparing adjuvant RT versus observation after LS are warranted.