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2.
Syst Rev ; 13(1): 103, 2024 Apr 06.
Article in English | MEDLINE | ID: mdl-38582929

ABSTRACT

The increasing prevalence and application of qualitative evidence syntheses (QES) in decision-making processes underscore the need for robust tools to assess the methodological limitations of a completed QES. This commentary discusses the limitations of three existing tools and presents the authors' efforts to address this gap. Through a simple comparative analysis, the three tools are examined in terms of their coverage of essential topic areas. The examination finds that existing assessment tools lack comprehensive coverage, clarity, and grounding in qualitative research principles. The authors advocate for the development of a new collaboratively developed evidence-based tool rooted in qualitative methodology and best practice methods. The conclusion emphasizes the necessity of a tool that can provide a comprehensive judgement on the methodological limitations of a QES, addressing the needs of end-users, and ultimately enhancing the trustworthiness of QES findings in decision-making processes.


Subject(s)
Evidence-Based Medicine , Humans , Qualitative Research
3.
BMC Geriatr ; 24(1): 24, 2024 01 05.
Article in English | MEDLINE | ID: mdl-38182977

ABSTRACT

BACKGROUND: Chronic primary low back pain (CPLBP) and other musculoskeletal conditions represent a sizable attribution to the global burden of disability, with rates greatest in older age. There are multiple and varied interventions for CPLBP, delivered by a wide range of health and care workers. However, it is not known if these are acceptable to or align with the values and preferences of care recipients. The objective of this synthesis was to understand the key factors influencing the acceptability of, and values and preferences for, interventions/care for CPLBP from the perspective of people over 60 and their caregivers. METHODS: We searched MEDLINE, CINAHL and OpenAlex, for eligible studies from inception until April 2022. We included studies that used qualitative methods for data collection and analysis; explored the perceptions and experiences of older people and their caregivers about interventions to treat CPLBP; from any setting globally. We conducted a best fit framework synthesis using a framework developed specifically for this review. We assessed our certainty in the findings using GRADE-CERQual. RESULTS: All 22 included studies represented older people's experiences and had representation across a range of geographies and economic contexts. No studies were identified on caregivers. Older people living with CPLBP express values and preferences for their care that relate to therapeutic encounters and the importance of therapeutic alliance, irrespective of the type of treatment, choice of intervention, and intervention delivery modalities. Older people with CPLBP value therapeutic encounters that validate, legitimise, and respect their pain experience, consider their context holistically, prioritise their needs and preferences, adopt a person-centred and tailored approach to care, and are supported by interprofessional communication. Older people valued care that provided benefit to them, included interventions beyond analgesic medicines alone and was financially and geographically accessible. CONCLUSIONS: These findings provide critical context to the implementation of clinical guidelines into practice, particularly related to how care providers interact with older people and how components of care are delivered, their location and their cost. Further research is needed focusing on low- and middle-income settings, vulnerable populations, and caregivers.


Subject(s)
Low Back Pain , Humans , Aged , Low Back Pain/diagnosis , Low Back Pain/epidemiology , Low Back Pain/therapy , Pain Management , Communication , Data Collection , Health Personnel
4.
Syst Rev ; 12(1): 7, 2023 01 17.
Article in English | MEDLINE | ID: mdl-36650579

ABSTRACT

BACKGROUND: Machine learning (ML) tools exist that can reduce or replace human activities in repetitive or complex tasks. Yet, ML is underutilized within evidence synthesis, despite the steadily growing rate of primary study publication and the need to periodically update reviews to reflect new evidence. Underutilization may be partially explained by a paucity of evidence on how ML tools can reduce resource use and time-to-completion of reviews. METHODS: This protocol describes how we will answer two research questions using a retrospective study design: Is there a difference in resources used to produce reviews using recommended ML versus not using ML, and is there a difference in time-to-completion? We will also compare recommended ML use to non-recommended ML use that merely adds ML use to existing procedures. We will retrospectively include all reviews conducted at our institute from 1 August 2020, corresponding to the commission of the first review in our institute that used ML. CONCLUSION: The results of this study will allow us to quantitatively estimate the effect of ML adoption on resource use and time-to-completion, providing our organization and others with better information to make high-level organizational decisions about ML.


Subject(s)
Machine Learning , Humans , Retrospective Studies , Pilot Projects
5.
Oncogene ; 41(50): 5361-5372, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36344676

ABSTRACT

Glioma stem cells (GSCs) promote tumor progression and therapeutic resistance and exhibit remarkable bioenergetic and metabolic plasticity, a phenomenon that has been linked to their ability to escape standard and targeted therapies. However, specific mechanisms that promote therapeutic resistance have been somewhat elusive. We hypothesized that because GSCs proliferate continuously, they may require the salvage and de novo nucleotide synthesis pathways to satisfy their bioenergetic needs. Here, we demonstrate that GSCs lacking EGFR (or EGFRvIII) amplification are exquisitely sensitive to de novo pyrimidine synthesis perturbations, while GSCs that amplify EGFR are utterly resistant. Furthermore, we show that EGFRvIII promotes BAY2402234 resistance in otherwise BAY2402234 responsive GSCs. Remarkably, a novel, orally bioavailable, blood-brain-barrier penetrating, dihydroorotate dehydrogenase (DHODH) inhibitor BAY2402234 was found to abrogate GSC proliferation, block cell-cycle progression, and induce DNA damage and apoptosis. When dosed daily by oral gavage, BAY2402234 significantly impaired the growth of two different intracranial human glioblastoma xenograft models in mice. Given this observed efficacy and the previously established safety profiles in preclinical animal models and human clinical trials, the clinical testing of BAY2402234 in patients with primary glioblastoma that lacks EGFR amplification is warranted.


Subject(s)
Brain Neoplasms , Glioblastoma , Glioma , Humans , Mice , Animals , Dihydroorotate Dehydrogenase , Neoplastic Stem Cells/pathology , Glioblastoma/drug therapy , Glioblastoma/genetics , Glioblastoma/metabolism , Glioma/drug therapy , Glioma/genetics , Glioma/pathology , DNA Damage , Cell Proliferation , Brain Neoplasms/drug therapy , Brain Neoplasms/genetics , Brain Neoplasms/pathology , Cell Line, Tumor
6.
BMC Med Res Methodol ; 22(1): 167, 2022 06 08.
Article in English | MEDLINE | ID: mdl-35676632

ABSTRACT

BACKGROUND: Machine learning and automation are increasingly used to make the evidence synthesis process faster and more responsive to policymakers' needs. In systematic reviews of randomized controlled trials (RCTs), risk of bias assessment is a resource-intensive task that typically requires two trained reviewers. One function of RobotReviewer, an off-the-shelf machine learning system, is an automated risk of bias assessment. METHODS: We assessed the feasibility of adopting RobotReviewer within a national public health institute using a randomized, real-time, user-centered study. The study included 26 RCTs and six reviewers from two projects examining health and social interventions. We randomized these studies to one of two RobotReviewer platforms. We operationalized feasibility as accuracy, time use, and reviewer acceptability. We measured accuracy by the number of corrections made by human reviewers (either to automated assessments or another human reviewer's assessments). We explored acceptability through group discussions and individual email responses after presenting the quantitative results. RESULTS: Reviewers were equally likely to accept judgment by RobotReviewer as each other's judgement during the consensus process when measured dichotomously; risk ratio 1.02 (95% CI 0.92 to 1.13; p = 0.33). We were not able to compare time use. The acceptability of the program by researchers was mixed. Less experienced reviewers were generally more positive, and they saw more benefits and were able to use the tool more flexibly. Reviewers positioned human input and human-to-human interaction as superior to even a semi-automation of this process. CONCLUSION: Despite being presented with evidence of RobotReviewer's equal performance to humans, participating reviewers were not interested in modifying standard procedures to include automation. If further studies confirm equal accuracy and reduced time compared to manual practices, we suggest that the benefits of RobotReviewer may support its future implementation as one of two assessors, despite reviewer ambivalence. Future research should study barriers to adopting automated tools and how highly educated and experienced researchers can adapt to a job market that is increasingly challenged by new technologies.


Subject(s)
Bias , Systematic Reviews as Topic , Humans , Machine Learning , Randomized Controlled Trials as Topic , Risk Assessment
7.
J Vis Exp ; (183)2022 05 09.
Article in English | MEDLINE | ID: mdl-35604202

ABSTRACT

The present protocol describes a standardized paradigm for rodent brain tumor resection and tissue preservation. In clinical practice, maximal tumor resection is the standard-of-care treatment for most brain tumors. However, most currently available preclinical brain tumor models either do not include resection, or utilize surgical resection models that are time-consuming and lead to significant postoperative morbidity, mortality, or experimental variability. In addition, performing resection in rodents can be daunting for several reasons, including a lack of clinically comparable surgical tools or protocols and the absence of an established platform for standardized tissue collection. This protocol highlights the use of a multi-functional, non-ablative resection device and an integrated tissue preservation system adapted from the clinical version of the device. The device applied in the present study combines tunable suction and a cylindrical blade at the aperture to precisely probe, cut, and suction tissue. The minimally invasive resection device performs its functions via the same burr hole used for the initial tumor implantation. This approach minimizes alterations to regional anatomy during biopsy or resection surgeries and reduces the risk of significant blood loss. These factors significantly reduced the operative time (<2 min/animal), improved postoperative animal survival, lower variability in experimental groups, and result in high viability of resected tissues and cells for future analyses. This process is facilitated by a blade speed of ~1,400 cycles/min, which allows the harvesting of tissues into a sterile closed system that can be filled with a physiologic solution of choice. Given the emerging importance of studying and accurately modeling the impact of surgery, preservation and rigorous comparative analysis of regionalized tumor resection specimens, and intra-cavity-delivered therapeutics, this unique protocol will expand opportunities to explore unanswered questions about perioperative management and therapeutic discovery for brain tumor patients.


Subject(s)
Brain Neoplasms , Rodentia , Animals , Brain/surgery , Brain Neoplasms/surgery , Humans , Microsurgery , Minimally Invasive Surgical Procedures/methods , Stereotaxic Techniques
8.
Nature ; 604(7907): 714-722, 2022 04.
Article in English | MEDLINE | ID: mdl-35444284

ABSTRACT

Dementia in Alzheimer's disease progresses alongside neurodegeneration1-4, but the specific events that cause neuronal dysfunction and death remain poorly understood. During normal ageing, neurons progressively accumulate somatic mutations5 at rates similar to those of dividing cells6,7 which suggests that genetic factors, environmental exposures or disease states might influence this accumulation5. Here we analysed single-cell whole-genome sequencing data from 319 neurons from the prefrontal cortex and hippocampus of individuals with Alzheimer's disease and neurotypical control individuals. We found that somatic DNA alterations increase in individuals with Alzheimer's disease, with distinct molecular patterns. Normal neurons accumulate mutations primarily in an age-related pattern (signature A), which closely resembles 'clock-like' mutational signatures that have been previously described in healthy and cancerous cells6-10. In neurons affected by Alzheimer's disease, additional DNA alterations are driven by distinct processes (signature C) that highlight C>A and other specific nucleotide changes. These changes potentially implicate nucleotide oxidation4,11, which we show is increased in Alzheimer's-disease-affected neurons in situ. Expressed genes exhibit signature-specific damage, and mutations show a transcriptional strand bias, which suggests that transcription-coupled nucleotide excision repair has a role in the generation of mutations. The alterations in Alzheimer's disease affect coding exons and are predicted to create dysfunctional genetic knockout cells and proteostatic stress. Our results suggest that known pathogenic mechanisms in Alzheimer's disease may lead to genomic damage to neurons that can progressively impair function. The aberrant accumulation of DNA alterations in neurodegeneration provides insight into the cascade of molecular and cellular events that occurs in the development of Alzheimer's disease.


Subject(s)
Alzheimer Disease , Neurons , Aging , Alzheimer Disease/genetics , Alzheimer Disease/pathology , DNA , Exons , Genomics , Hippocampus/cytology , Humans , Mutation Rate , Neurons/pathology , Nucleotides , Prefrontal Cortex/cytology , Whole Genome Sequencing
9.
JAMA Neurol ; 79(6): 544-553, 2022 06 01.
Article in English | MEDLINE | ID: mdl-35404378

ABSTRACT

Importance: Loss of smell is an early and common presentation of COVID-19 infection. Although it has been speculated that viral infection of olfactory neurons may be the culprit, it is unclear whether viral infection causes injuries in the olfactory bulb region. Objective: To characterize the olfactory pathology associated with COVID-19 infection in a postmortem study. Design, Setting, and Participants: This multicenter postmortem cohort study was conducted from April 7, 2020, to September 11, 2021. Deceased patients with COVID-19 and control individuals were included in the cohort. One infant with congenital anomalies was excluded. Olfactory bulb and tract tissue was collected from deceased patients with COVID-19 and appropriate controls. Histopathology, electron microscopy, droplet digital polymerase chain reaction, and immunofluorescence/immunohistochemistry studies were performed. Data analysis was conducted from February 7 to October 19, 2021. Main Outcomes and Measures: (1) Severity of degeneration, (2) losses of olfactory axons, and (3) severity of microvasculopathy in olfactory tissue. Results: Olfactory tissue from 23 deceased patients with COVID-19 (median [IQR] age, 62 [49-69] years; 14 men [60.9%]) and 14 control individuals (median [IQR] age, 53.5 [33.25-65] years; 7 men [50%]) was included in the analysis. The mean (SD) axon pathology score (range, 1-3) was 1.921 (0.569) in patients with COVID-19 and 1.198 (0.208) in controls (P < .001), whereas axon density was 2.973 (0.963) × 104/mm2 in patients with COVID-19 and 3.867 (0.670) × 104/mm2 in controls (P = .002). Concomitant endothelial injury of the microvasculature was also noted in olfactory tissue. The mean (SD) microvasculopathy score (range, 1-3) was 1.907 (0.490) in patients with COVID-19 and 1.405 (0.233) in control individuals (P < .001). Both the axon and microvascular pathology was worse in patients with COVID-19 with smell alterations than those with intact smell (mean [SD] axon pathology score, 2.260 [0.457] vs 1.63 [0.426]; P = .002; mean [SD] microvasculopathy score, 2.154 [0.528] vs 1.694 [0.329]; P = .02) but was not associated with clinical severity, timing of infection, or presence of virus. Conclusions and Relevance: This study found that COVID-19 infection is associated with axon injuries and microvasculopathy in olfactory tissue. The striking axonal pathology in some cases indicates that olfactory dysfunction in COVID-19 infection may be severe and permanent.


Subject(s)
COVID-19 , Olfaction Disorders , Cohort Studies , Humans , Male , Middle Aged , Olfaction Disorders/etiology , SARS-CoV-2 , Smell/physiology
10.
Res Synth Methods ; 13(2): 229-241, 2022 Mar.
Article in English | MEDLINE | ID: mdl-34919321

ABSTRACT

Systematic reviews are resource-intensive. The machine learning tools being developed mostly focus on the study identification process, but tools to assist in analysis and categorization are also needed. One possibility is to use unsupervised automatic text clustering, in which each study is automatically assigned to one or more meaningful clusters. Our main aim was to assess the usefulness of an automated clustering method, Lingo3G, in categorizing studies in a simplified rapid review, then compare performance (precision and recall) of this method compared to manual categorization. We randomly assigned all 128 studies in a review to be coded by a human researcher blinded to cluster assignment (mimicking two independent researchers) or by a human researcher non-blinded to cluster assignment (mimicking one researcher checking another's work). We compared time use, precision and recall of manual categorization versus automated clustering. Automated clustering and manual categorization organized studies by population and intervention/context. Automated clustering failed to identify two manually identified categories but identified one additional category not identified by the human researcher. We estimate that automated clustering has similar precision to both blinded and non-blinded researchers (e.g., 88% vs. 89%), but higher recall (e.g., 89% vs. 84%). Manual categorization required 49% more time than automated clustering. Using a specific clustering algorithm, automated clustering can be helpful with categorization of and identifying patterns across studies in simpler systematic reviews. We found that the clustering was sensitive enough to group studies according to linguistic differences that often corresponded to the manual categories.


Subject(s)
Algorithms , Machine Learning , Cluster Analysis , Humans , Research Design , Systematic Reviews as Topic
11.
Glia ; 69(9): 2199-2214, 2021 09.
Article in English | MEDLINE | ID: mdl-33991013

ABSTRACT

High-grade gliomas (HGGs) are aggressive, treatment-resistant, and often fatal human brain cancers. The TNF-like weak inducer of apoptosis (TWEAK)/fibroblast growth factor-inducible 14 (Fn14) signaling axis is involved in tissue repair after injury and constitutive signaling has been implicated in the pathogenesis of numerous solid cancers. The Fn14 gene is expressed at low levels in the normal, uninjured brain but is highly expressed in primary isocitrate dehydrogenase wild-type and recurrent HGGs. Fn14 signaling is implicated in numerous aspects of glioma biology including brain invasion and chemotherapy resistance, but whether Fn14 overexpression can directly promote tumor malignancy has not been reported. Here, we used the replication-competent avian sarcoma-leukosis virus/tumor virus A system to examine the impact of Fn14 expression on glioma development and pathobiology. We found that the sole addition of Fn14 to an established oncogenic cocktail previously shown to generate proneural-like gliomas led to the development of highly invasive and lethal brain cancer with striking biological features including extensive pseudopalisading necrosis, constitutive canonical and noncanonical NF-κB pathway signaling, and high plasminogen activator inhibitor-1 (PAI-1) expression. Analyses of HGG patient datasets revealed that high human PAI-1 gene (SERPINE1) expression correlates with shorter patient survival, and that the SERPINE1 and Fn14 (TNFRSF12A) genes are frequently co-expressed in bulk tumor tissues, in tumor subregions, and in malignant cells residing in the tumor microenvironment. These findings provide new insights into the potential importance of Fn14 in human HGG pathobiology and designate both the NF-κB signaling node and PAI-1 as potential targets for therapeutic intervention. MAIN POINTS: This work demonstrates that elevated levels of the TWEAK receptor Fn14 in tumor-initiating, neural progenitor cells leads to the transformation of proneural-like gliomas into more aggressive and lethal tumors that exhibit constitutive NF-κB pathway activation and plasminogen activator inhibitor-1 overexpression.


Subject(s)
Brain Neoplasms , Glioma , Brain Neoplasms/pathology , Cell Line, Tumor , Fibroblast Growth Factors , Glioma/pathology , Humans , Neoplasm Invasiveness , Receptors, Tumor Necrosis Factor/genetics , Receptors, Tumor Necrosis Factor/metabolism , TWEAK Receptor , Tumor Microenvironment
12.
Glia ; 69(9): 2059-2076, 2021 09.
Article in English | MEDLINE | ID: mdl-33638562

ABSTRACT

Gliomas are the most common primary intrinsic brain tumors occurring in adults. Of all malignant gliomas, glioblastoma (GBM) is considered the deadliest tumor type due to diffuse brain invasion, immune evasion, cellular, and molecular heterogeneity, and resistance to treatments resulting in high rates of recurrence. An extensive understanding of the genomic and microenvironmental landscape of gliomas gathered over the past decade has renewed interest in pursuing novel therapeutics, including immune checkpoint inhibitors, glioma-associated macrophage/microglia (GAMs) modulators, and others. In light of this, predictive animal models that closely recreate the conditions and findings found in human gliomas will serve an increasingly important role in identifying new, effective therapeutic strategies. Although numerous syngeneic, xenograft, and transgenic rodent models have been developed, few include the full complement of pathobiological features found in human tumors, and therefore few accurately predict bench-to-bedside success. This review provides an update on how genetically engineered rodent models based on the replication-competent avian-like sarcoma (RCAS) virus/tumor virus receptor-A (tv-a) system have been used to recapitulate key elements of human gliomas in an immunologically intact host microenvironment and highlights new approaches using this model system as a predictive tool for advancing translational glioma research.


Subject(s)
Brain Neoplasms , Disease Models, Animal , Glioma , Sarcoma , Animals , Avian Sarcoma Viruses/genetics , Brain Neoplasms/pathology , Glioma/pathology , Humans , Oncogenic Viruses , Receptors, Virus , Tumor Microenvironment
13.
Cancer Res ; 80(21): 4681-4692, 2020 11 01.
Article in English | MEDLINE | ID: mdl-32928918

ABSTRACT

Muscleblind-like proteins (MBNL) belong to a family of tissue-specific regulators of RNA metabolism that control premessenger RNA splicing. Inactivation of MBNL causes an adult-to-fetal alternative splicing transition, resulting in the development of myotonic dystrophy. We have previously shown that the aggressive brain cancer, glioblastoma (GBM), maintains stem-like features (glioma stem cell, GSC) through hypoxia-induced responses. Accordingly, we hypothesize here that hypoxia-induced responses in GBM might also include MBNL-based alternative splicing to promote tumor progression. When cultured in hypoxia condition, GSCs rapidly exported muscleblind-like-1 (MBNL1) out of the nucleus, resulting in significant inhibition of MBNL1 activity. Notably, hypoxia-regulated inhibition of MBNL1 also resulted in evidence of adult-to-fetal alternative splicing transitions. Forced expression of a constitutively active isoform of MBNL1 inhibited GSC self-renewal and tumor initiation in orthotopic transplantation models. Induced expression of MBNL1 in established orthotopic tumors dramatically inhibited tumor progression, resulting in significantly prolonged survival. This study reveals that MBNL1 plays an essential role in GBM stemness and tumor progression, where hypoxic responses within the tumor inhibit MBNL1 activity, promoting stem-like phenotypes and tumor growth. Reversing these effects on MBNL1 may therefore, yield potent tumor suppressor activities, uncovering new therapeutic opportunities to counter this disease. SIGNIFICANCE: This study describes an unexpected mechanism by which RNA-binding protein, MBNL1, activity is inhibited in hypoxia by a simple isoform switch to regulate glioma stem cell self-renewal, tumorigenicity, and progression.


Subject(s)
Brain Neoplasms/pathology , Glioblastoma/pathology , Neoplastic Stem Cells/pathology , RNA-Binding Proteins/metabolism , Alternative Splicing/physiology , Animals , Cell Hypoxia/physiology , Disease Progression , Heterografts , Humans , Mice
14.
Cancer Res ; 80(8): 1644-1655, 2020 04 15.
Article in English | MEDLINE | ID: mdl-32094299

ABSTRACT

Glioblastoma multiforme (GBM) and other solid malignancies are heterogeneous and contain subpopulations of tumor cells that exhibit stem-like features. Our recent findings point to a dedifferentiation mechanism by which reprogramming transcription factors Oct4 and Sox2 drive the stem-like phenotype in glioblastoma, in part, by differentially regulating subsets of miRNAs. Currently, the molecular mechanisms by which reprogramming transcription factors and miRNAs coordinate cancer stem cell tumor-propagating capacity are unclear. In this study, we identified miR-486-5p as a Sox2-induced miRNA that targets the tumor suppressor genes PTEN and FoxO1 and regulates the GBM stem-like cells. miR-486-5p associated with the GBM stem cell phenotype and Sox2 expression and was directly induced by Sox2 in glioma cell lines and patient-derived neurospheres. Forced expression of miR-486-5p enhanced the self-renewal capacity of GBM neurospheres, and inhibition of endogenous miR-486-5p activated PTEN and FoxO1 and induced cell death by upregulating proapoptotic protein BIM via a PTEN-dependent mechanism. Furthermore, delivery of miR-486-5p antagomirs to preestablished orthotopic GBM neurosphere-derived xenografts using advanced nanoparticle formulations reduced tumor sizes in vivo and enhanced the cytotoxic response to ionizing radiation. These results define a previously unrecognized and therapeutically targetable Sox2:miR-486-5p axis that enhances the survival of GBM stem cells by repressing tumor suppressor pathways. SIGNIFICANCE: This study identifies a novel axis that links core transcriptional drivers of cancer cell stemness to miR-486-5p-dependent modulation of tumor suppressor genes that feeds back to regulate glioma stem cell survival.


Subject(s)
Brain Neoplasms/pathology , Cell Survival , Forkhead Box Protein O1/genetics , Genes, Tumor Suppressor , Glioblastoma/pathology , MicroRNAs/metabolism , Neoplasm Proteins/physiology , PTEN Phosphohydrolase/genetics , SOXB1 Transcription Factors/physiology , Animals , Bcl-2-Like Protein 11/metabolism , Brain Neoplasms/genetics , Brain Neoplasms/metabolism , Brain Neoplasms/radiotherapy , Cell Death , Cell Dedifferentiation/genetics , Cell Line, Tumor , Cellular Reprogramming/physiology , Epigenetic Repression , Female , Gene Expression Regulation, Neoplastic , Glioblastoma/genetics , Glioblastoma/metabolism , Glioblastoma/radiotherapy , Heterografts , Humans , Mice , Mice, Nude , MicroRNAs/administration & dosage , MicroRNAs/antagonists & inhibitors , MicroRNAs/genetics , Nanoparticles/administration & dosage , Neoplasm Proteins/genetics , Neoplastic Stem Cells/metabolism , Neoplastic Stem Cells/pathology , Neoplastic Stem Cells/radiation effects , Neural Stem Cells , Octamer Transcription Factor-3/metabolism , Radiation Tolerance , Random Allocation , SOXB1 Transcription Factors/genetics , SOXB1 Transcription Factors/metabolism , Transfection/methods , Tumor Burden , Tumor Stem Cell Assay/methods , Up-Regulation
15.
Neurooncol Adv ; 2(1): vdz062, 2020.
Article in English | MEDLINE | ID: mdl-32002519

ABSTRACT

BACKGROUND: Necrotic foci with surrounding hypoxic cellular pseudopalisades and microvascular hyperplasia are histological features found in glioblastoma (GBM). We have previously shown that monocarboxylate transporter 4 (MCT4) is highly expressed in necrotic/hypoxic regions in GBM and that increased levels of MCT4 are associated with worse clinical outcomes. METHODS: A combined transcriptomics and metabolomics analysis was performed to study the effects of MCT4 depletion in hypoxic GBM neurospheres. Stable and inducible MCT4-depletion systems were used to evaluate the effects of and underlining mechanisms associated with MCT4 depletion in vitro and in vivo, alone and in combination with radiation. RESULTS: This study establishes that conditional depletion of MCT4 profoundly impairs self-renewal and reduces the frequency and tumorigenicity of aggressive, therapy-resistant, glioblastoma stem cells. Mechanistically, we observed that MCT4 depletion induces anaplerotic glutaminolysis and abrogates de novo pyrimidine biosynthesis. The latter results in a dramatic increase in DNA damage and apoptotic cell death, phenotypes that were readily rescued by pyrimidine nucleosides supplementation. Consequently, we found that MCT4 depletion promoted a significant prolongation of survival of animals bearing established orthotopic xenografts, an effect that was extended by adjuvant treatment with focused radiation. CONCLUSIONS: Our findings establish a novel role for MCT4 as a critical regulator of cellular deoxyribonucleotide levels and provide a new therapeutic direction related to MCT4 depletion in GBM.

16.
Sci Adv ; 6(3): eaax3931, 2020 01.
Article in English | MEDLINE | ID: mdl-31998833

ABSTRACT

Development of effective tumor cell-targeted nanodrug formulations has been quite challenging, as many nanocarriers and targeting moieties exhibit nonspecific binding to cellular, extracellular, and intravascular components. We have developed a therapeutic nanoparticle formulation approach that balances cell surface receptor-specific binding affinity while maintaining minimal interactions with blood and tumor tissue components (termed "DART" nanoparticles), thereby improving blood circulation time, biodistribution, and tumor cell-specific uptake. Here, we report that paclitaxel (PTX)-DART nanoparticles directed to the cell surface receptor fibroblast growth factor-inducible 14 (Fn14) outperformed both the corresponding PTX-loaded, nontargeted nanoparticles and Abraxane, an FDA-approved PTX nanoformulation, in both a primary triple-negative breast cancer (TNBC) model and an intracranial model reflecting TNBC growth following metastatic dissemination to the brain. These results provide new insights into methods for effective development of therapeutic nanoparticles as well as support the continued development of the DART platform for primary and metastatic tumors.


Subject(s)
Antineoplastic Agents/administration & dosage , Biomarkers, Tumor , Breast Neoplasms/genetics , Breast Neoplasms/pathology , Molecular Targeted Therapy , Nanoparticles , Theranostic Nanomedicine , Animals , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacokinetics , Breast Neoplasms/drug therapy , Breast Neoplasms/mortality , Disease Models, Animal , Extracellular Matrix , Female , Gene Expression , Humans , Mice , Molecular Targeted Therapy/adverse effects , Molecular Targeted Therapy/methods , Neoplasm Metastasis , Neoplasm Staging , Prognosis , RNA, Messenger , TWEAK Receptor/genetics , Tissue Distribution , Treatment Outcome , Triple Negative Breast Neoplasms/drug therapy , Triple Negative Breast Neoplasms/etiology , Triple Negative Breast Neoplasms/pathology , Xenograft Model Antitumor Assays
17.
Cochrane Database Syst Rev ; 10: CD013447, 2019 10 14.
Article in English | MEDLINE | ID: mdl-31608981

ABSTRACT

BACKGROUND: Governments and health systems are increasingly using mobile devices to communicate with patients and the public. Targeted digital client communication is when the health system transmits information to particular individuals or groups of people, based on their health or demographic status. Common types of targeted client communication are text messages that remind people to go to appointments or take their medicines. Other types include phone calls, interactive voice response, or multimedia messages that offer healthcare information, advice, monitoring, and support. OBJECTIVES: To explore clients' perceptions and experiences of targeted digital communication via mobile devices on topics related to reproductive, maternal, newborn, child, or adolescent health (RMNCAH). SEARCH METHODS: We searched MEDLINE (OvidSP), MEDLINE In-Process & Other Non-Indexed Citations (OvidSP), Embase (Ovid), World Health Organization Global Health Library, and POPLINE databases for eligible studies from inception to 3-6 July 2017 dependant on the database (See appendix 2). SELECTION CRITERIA: We included studies that used qualitative methods for data collection and analysis; that explored clinets' perceptions and experiences of targeted digital communication via mobile device in the areas of RMNCAH; and were from any setting globally. DATA COLLECTION AND ANALYSIS: We used maximum variation purposive sampling for data synthesis, employing a three-step sampling frame. We conducted a framework thematic analysis using the Supporting the Use of Research Evidence (SURE) framework as our starting point. We assessed our confidence in the findings using the GRADE-CERQual (Confidence in the Evidence from Reviews of Qualitative research) approach. We used a matrix approach to explore whether potential implementation barriers identified in our synthesis had been addressed in the trials included in the related Cochrane Reviews of effectiveness. MAIN RESULTS: We included 35 studies, from a wide range of countries on six continents. Nineteen studies were conducted in low- and middle-income settings and sixteen in high-income settings. Some of the studies explored the views of people who had experienced the interventions, whereas others were hypothetical in nature, asking what people felt they would like from a digital health intervention. The studies covered a range of digital targeted client communication, for example medication or appointment reminders, prenatal health information, support for smoking cessation while pregnant, or general sexual health information.Our synthesis showed that clients' experiences of these types of programmes were mixed. Some felt that these programmes provided them with feelings of support and connectedness, as they felt that someone was taking the time to send them messages (moderate confidence in the evidence). They also described sharing the messages with their friends and family (moderate confidence).However, clients also pointed to problems when using these programmes. Some clients had poor access to cell networks and to the internet (high confidence). Others had no phone, had lost or broken their phone, could not afford airtime, or had changed their phone number (moderate confidence). Some clients, particularly women and teenagers, had their access to phones controlled by others (moderate confidence). The cost of messages could also be a problem, and many thought that messages should be free of charge (high confidence). Language issues as well as skills in reading, writing, and using mobile phones could also be a problem (moderate confidence).Clients dealing with stigmatised or personal health conditions such as HIV, family planning, or abortion care were also concerned about privacy and confidentiality (high confidence). Some clients suggested strategies to deal with these issues, such as using neutral language and tailoring the content, timing, and frequency of messages (high confidence).Clients wanted messages at a time and frequency that was convenient for them (moderate confidence). They had preferences for different delivery channels (e.g. short message service (SMS) or interactive voice response) (moderate confidence). They also had preferences about message content, including new knowledge, reminders, solutions, and suggestions about health issues (moderate confidence). Clients' views about who sent the digital health communication could influence their views of the programme (moderate confidence).For an overview of the findings and our confidence in the evidence, please see the 'Summary of qualitative findings' tables.Our matrix shows that many of the trials assessing these types of programmes did not try to address the problems we identified, although this may have been a reporting issue. AUTHORS' CONCLUSIONS: Our synthesis identified several factors that can influence the successful implementation of targeted client communication programmes using mobile devices. These include barriers to use that have equity implications. Programme planners should take these factors into account when designing and implementing programmes. Future trial authors also need to actively address these factors and to report their efforts in their trial publications.

18.
Nanomedicine ; 20: 102024, 2019 08.
Article in English | MEDLINE | ID: mdl-31176045

ABSTRACT

Therapeutic efficacy of nanoparticle-drug formulations for cancer applications is significantly impacted by the extent of intra-tumoral accumulation and tumor tissue penetration. We advanced the application of surface plasmon resonance to examine interfacial properties of various clinical and emerging nanoparticles related to tumor tissue penetration. We observed that amine-terminated or positively-charged dendrimers and liposomes bound strongly to tumor extracellular matrix (ECM) proteins, whereas hydroxyl/carboxyl-terminated dendrimers and PEGylated/neutrally-charged liposomes did not bind. In addition, poly(lactic-co-glycolic acid) (PLGA) nanoparticles formulated with cholic acid or F127 surfactants bound strongly to tumor ECM proteins, whereas nanoparticles formulated with poly(vinyl alcohol) did not bind. Unexpectedly, following blood serum incubation, this binding increased and particle transport in ex vivo tumor tissues reduced markedly. Finally, we characterized the protein corona on PLGA nanoparticles using quantitative proteomics. Through these studies, we identified valuable criteria for particle surface characteristics that are likely to mediate their tissue binding and tumor penetration.


Subject(s)
Nanoparticles/chemistry , Neoplasms/metabolism , Surface Plasmon Resonance , Animals , Biological Transport , Blood Proteins/metabolism , Cell Line, Tumor , Dendrimers/chemistry , Extracellular Matrix Proteins/metabolism , Female , Humans , Liposomes , Mice, Nude , Nanoparticles/ultrastructure , Polylactic Acid-Polyglycolic Acid Copolymer/chemistry , Protein Binding , Protein Corona/chemistry , Surface Properties , Surface-Active Agents/chemistry
19.
J Neurooncol ; 143(1): 87-93, 2019 May.
Article in English | MEDLINE | ID: mdl-30864101

ABSTRACT

PURPOSE: H3 K27 mutations, most commonly in H3F3A, are common in diffuse midline glioma. The exact frequency of these mutations in adults with gliomas in the midline location is unknown. This study was conducted to define the incidence of H3 K27M mutations in this location and to compare clinicopathological features with those of patients who do not harbor this mutation. METHODS: Consecutive glioma cases from 2007 to 2017 were screened for gliomas in the midline location. Immunohistochemistry was performed on all available tissue for mutations of H3 K27M, IDH1, and ARTX. RESULTS: Of 850 gliomas screened, 163 cases had midline glioma on MRI. Sufficient FFPE tissue was available for 123 cases (75%). H3 K27M mutation was identified in 18 of 123 cases (15%). All except one H3 K27M-mutant tumors were WHO grade III or IV on histology, while non-mutant tumors encompassed all four grades. The most common midline locations for H3 K27M-mutated tumors were midbrain (2/3; 67%), pons (4/11; 36%), and cerebellum (6/24; 25%). As compared to H3 K27M-wildtype tumors, there were no differences in age at diagnosis, sex, tumor grade, contrast enhancement on MRI, extent of resection, or treatment received. In this cohort, median survival was longer for patients with H3 K27M-mutated tumors (n = 18; 17.6 months) compared with high-grade wildtype tumors (n = 74; 7.7 months, p = 0.03). CONCLUSIONS: H3 K27M mutations are common in midline gliomas in adults and can present in all midline locations. Survival comparison between H3 K27M-mutant and wildtype midline gliomas suggests that survival may be similar or possibly improved if the mutation is present.


Subject(s)
Brain Neoplasms/epidemiology , Brain Neoplasms/pathology , Glioma/epidemiology , Glioma/pathology , Histones/genetics , Mutation , Adult , Aged , Aged, 80 and over , Biomarkers, Tumor/genetics , Brain/pathology , Brain Neoplasms/genetics , Brain Neoplasms/therapy , Cohort Studies , Female , Glioma/genetics , Glioma/therapy , Humans , Incidence , Male , Middle Aged , Neoplasm Grading , Survival Analysis , Young Adult
20.
Adv Parasitol ; 103: 117-149, 2019.
Article in English | MEDLINE | ID: mdl-30878056

ABSTRACT

STUDY OBJECTIVES: This article presents findings from a rapid review of qualitative research conducted to inform decision makers about community and drug distributor perceptions and experiences of mass drug administration campaigns for the elimination of lymphatic filariasis. We focused on questions related to acceptability of the mass drug administration campaigns within these groups and their thoughts around the feasibility of planning and carrying out the campaigns. METHODS: We carried out a systematic search in five databases to identify potential studies. We included studies that focused on community members and drug distributors and used qualitative methods for data collection and analysis. We conducted a thematic framework analysis using the Supporting the Use of Research Evidence framework. Due to time constraints, one author conducted the screening, extraction and data analysis. FINDINGS: Studies found that communities lack knowledge and information about lymphatic filariasis and the mass drug administration campaigns and that this can have an impact on how many community members choose to take medication. Health workers often had a good understanding that lymphatic filariasis was a problem in their setting, of its cause and mode of transmission and that hydrocele and elephantiasis had the same cause. However, this knowledge was not as prevalent amongst community drug distributors who often had misconceptions surrounding the topic. Furthermore, studies found that the length, timing, level of community and health system involvement, access to care for side effects, inadequate numbers of drug distributors and supervisors and motivation of drug distributors influenced participation in mass drug administration campaigns. Finally, the inadequate training of drug distributors could influence community trust in the mass drug administration program and the drug distributor themselves if there was a perception that the person was uninformed or not trained to carry out their tasks.


Subject(s)
Disease Eradication , Elephantiasis, Filarial/prevention & control , Mass Drug Administration/psychology , Volunteers/psychology , Delivery of Health Care , Elephantiasis, Filarial/drug therapy , Humans , Mass Drug Administration/statistics & numerical data , Research
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