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The transfer of intact mitochondria between heterogeneous cell types has been confirmed in various settings, including cancer. However, the functional implications of mitochondria transfer on tumor biology are poorly understood. Here we show that mitochondria transfer is a prevalent phenomenon in glioblastoma (GBM), the most frequent and malignant primary brain tumor. We identified horizontal mitochondria transfer from astrocytes as a mechanism that enhances tumorigenesis in GBM. This transfer is dependent on network-forming intercellular connections between GBM cells and astrocytes, which are facilitated by growth-associated protein 43 (GAP43), a protein involved in neuron axon regeneration and astrocyte reactivity. The acquisition of astrocyte mitochondria drives an increase in mitochondrial respiration and upregulation of metabolic pathways linked to proliferation and tumorigenicity. Functionally, uptake of astrocyte mitochondria promotes cell cycle progression to proliferative G2/M phases and enhances self-renewal and tumorigenicity of GBM. Collectively, our findings reveal a host–tumor interaction that drives proliferation and self-renewal of cancer cells, providing opportunities for therapeutic development.

Glioblastomas (GBMs) are heterogeneous, treatment-resistant tumors driven by populations of cancer stem cells (CSCs). However, few molecular mechanisms critical for CSC population maintenance have been exploited for therapeutic development. We developed a spatially resolved loss-of-function screen in GBM patient-derived organoids to identify essential epigenetic regulators in the SOX2-enriched, therapy-resistant niche and identified WDR5 as indispensable for this population. WDR5 is a component of the WRAD complex, which promotes SET1 family-mediated Lys4 methylation of histone H3 (H3K4me), associated with positive regulation of transcription. In GBM CSCs, WDR5 inhibitors blocked WRAD complex assembly and reduced H3K4 trimethylation and expression of genes involved in CSC-relevant oncogenic pathways. H3K4me3 peaks lost with WDR5 inhibitor treatment occurred disproportionally on POU transcription factor motifs, including the POU5F1(OCT4)::SOX2 motif. Use of a SOX2/OCT4 reporter demonstrated that WDR5 inhibitor treatment diminished cells with high reporter activity. Furthermore, WDR5 inhibitor treatment and WDR5 knockdown altered the stem cell state, disrupting CSC in vitro growth and self-renewal, as well as in vivo tumor growth. These findings highlight the role of WDR5 and the WRAD complex in maintaining the CSC state and provide a rationale for therapeutic development of WDR5 inhibitors for GBM and other advanced cancers.

Synthetic lethality is a genetic interaction that results in cell death when two genetic deficiencies co-occur but not when either deficiency occurs alone, which can be co-opted for cancer therapeutics. Pairs of paralog genes are among the most straightforward potential synthetic–lethal interactions by virtue of their redundant functions. Here, we demonstrate a paralog-based synthetic lethality by targeting vaccinia-related kinase 1 (VRK1) in glioblastoma (GBM) deficient of VRK2, which is silenced by promoter methylation in approximately two thirds of GBM. Genetic knockdown of VRK1 in VRK2-null or VRK2-methylated cells resulted in decreased activity of the downstream substrate barrier to autointegration factor (BAF), a regulator of post-mitotic nuclear envelope formation. Reduced BAF activity following VRK1 knockdown caused nuclear lobulation, blebbing, and micronucleation, which subsequently resulted in G2–M arrest and DNA damage. The VRK1–VRK2 synthetic–lethal interaction was dependent on VRK1 kinase activity and was rescued by ectopic expression of VRK2. In VRK2-methylated GBM cell line–derived xenograft and patient-derived xenograft models, knockdown of VRK1 led to robust tumor growth inhibition. These results indicate that inhibiting VRK1 kinase activity could be a viable therapeutic strategy in VRK2-methylated GBM. Significance: A paralog synthetic–lethal interaction between VRK1 and VRK2 sensitizes VRK2-methylated glioblastoma to perturbation of VRK1 kinase activity, supporting VRK1 as a drug discovery target in this disease.

With climate, biodiversity and inequity crises squarely upon us, never has there been a more pressing time to rethink how we conceptualize, understand and manage our relationship with Earth's biodiversity. Here, we describe governance principles of 17 Indigenous Nations from the Northwest Coast of North America used to understand and steward relationships among all components of nature, including humans. We then chart the colonial origins of biodiversity science and use the complex case of sea otter recovery to illuminate how ancestral governance principles can be mobilized to characterize, manage and restore biodiversity in more inclusive, integrative and equitable ways. To enhance environmental sustainability, resilience and social justice amid today's crises, we need to broaden who benefits from and participates in the sciences of biodiversity by expanding the values and methodologies that shape such initiatives. In practice, biodiversity conservation and natural resource management need to shift from centralized, siloed approaches to those that can accommodate plurality in values, objectives, governance systems, legal traditions and ways of knowing. In doing so, developing solutions to our planetary crises becomes a shared responsibility. This article is part of the theme issue ‘Detecting and attributing the causes of biodiversity change: needs, gaps and solutions’.

In multiple types of cancer, an increased frequency in myeloid-derived suppressor cells (MDSC) is associated with worse outcomes and poor therapeutic response. In the glioblastoma (GBM) microenvironment, monocytic (m) MDSCs represent the predominant subset. However, the molecular basis of mMDSC enrichment in the tumor microenvironment compared with granulocytic (g) MDSCs has yet to be determined. Here we performed the first broad epigenetic profiling of MDSC subsets to define underlying cell-intrinsic differences in behavior and found that enhanced gene accessibility of cell adhesion programs in mMDSCs is linked to their tumor-accelerating ability in GBM models upon adoptive transfer. Mouse and human mMDSCs expressed higher levels of integrin β1 and dipeptidyl peptidase-4 (DPP-4) compared with gMDSCs as part of an enhanced cell adhesion signature. Integrin β1 blockade abrogated the tumor-promoting phenotype of mMDSCs and altered the immune profile in the tumor microenvironment, whereas treatment with a DPP-4 inhibitor extended survival in preclinical GBM models. Targeting DPP-4 in mMDSCs reduced pERK signaling and their migration towards tumor cells. These findings uncover a fundamental difference in the molecular basis of MDSC subsets and suggest that integrin β1 and DPP-4 represent putative immunotherapy targets to attenuate myeloid cell-driven immune suppression in GBM.Significance:Epigenetic profiling uncovers cell adhesion programming as a regulator of the tumor-promoting functions of monocytic myeloid-derived suppressor cells in glioblastoma, identifying therapeutic targets that modulate the immune response and suppress tumor growth.

Supplementary Data from Distinct Cell Adhesion Signature Defines Glioblastoma Myeloid-Derived Suppressor Cell Subsets

Supplementary Table S1

Glioblastomas (GBM) are lethal brain tumors where poor outcome is attributed to cellular heterogeneity, therapeutic resistance, and a highly infiltrative nature. These characteristics are preferentially linked to GBM cancer stem cells (GSC), but how GSCs maintain their stemness is incompletely understood and the subject of intense investigation. Here, we identify a novel signaling loop that induces and maintains GSCs consisting of an atypical metalloproteinase, ADAMDEC1, secreted by GSCs. ADAMDEC1 rapidly solubilizes FGF2 to stimulate FGFR1 expressed on GSCs. FGFR1 signaling induces upregulation of ZEB1 via ERK1/2 that regulates ADAMDEC1 expression through miR-203, creating a positive feedback loop. Genetic or pharmacologic targeting of components of this axis attenuates self-renewal and tumor growth. These findings reveal a new signaling axis for GSC maintenance and highlight ADAMDEC1 and FGFR1 as potential therapeutic targets in GBM.Significance:Cancer stem cells (CSC) drive tumor growth in many cancers including GBM. We identified a novel sheddase, ADAMDEC1, which initiates an FGF autocrine loop to promote stemness in CSCs. This loop can be targeted to reduce GBM growth.This article is highlighted in the In This Issue feature, p. 1469

Supplementary Figure S6

Supplementary Figures 1-9

Gene list for network medicine

Supplementary Table 4: List of cell lines evaluated for sensitivity to SHP099 (Tab 1) or an RTK-inhibitor (Tab 2) in 2D or 3D. Included is the lineage and the KRAS mutation status. Where data are blank, no viable data was available, or the cell line did not grow appropriately as a tumor spheroid.

In vivo efficacy of SHP099 (100 mg/kg, daily) in the KYSE-520 esophageal cancer cell line model. Data are plotted as the treatment mean {plus minus} s.e.m (n=7) ( (B-I) In vivo efficacy data for cell line models represented in Fig. 3E. SHP099 and trametinib were orally administered at the doses, schedules and for the duration indicated. Data are plotted as the treatment mean {plus minus} s.e.m.

Supplementary Material and Methods. File contains the following: Transcriptome sequencing and analysis, Soft agar assay, 2D and 3D Cell proliferation screen and compound characterization information.

Myeloid-derived suppressor cells (MDSC) that block antitumor immunity are elevated in glioblastoma (GBM) patient blood and tumors. However, the distinct contributions of monocytic (mMDSC) versus granulocytic (gMDSC) subsets have yet to be determined. In mouse models of GBM, we observed that mMDSCs were enriched in the male tumors, whereas gMDSCs were elevated in the blood of females. Depletion of gMDSCs extended survival only in female mice. Using gene-expression signatures coupled with network medicine analysis, we demonstrated in preclinical models that mMDSCs could be targeted with antiproliferative agents in males, whereas gMDSC function could be inhibited by IL1β blockade in females. Analysis of patient data confirmed that proliferating mMDSCs were predominant in male tumors and that a high gMDSC/IL1β gene signature correlated with poor prognosis in female patients. These findings demonstrate that MDSC subsets differentially drive immune suppression in a sex-specific manner and can be leveraged for therapeutic intervention in GBM.Significance:Sexual dimorphism at the level of MDSC subset prevalence, localization, and gene-expression profile constitutes a therapeutic opportunity. Our results indicate that chemotherapy can be used to target mMDSCs in males, whereas IL1 pathway inhibitors can provide benefit to females via inhibition of gMDSCs.See related commentary by Gabrilovich et al., p. 1100.This article is highlighted in the In This Issue feature, p. 1079

The nearly universal recurrence of glioblastoma (GBM) is driven in part by a treatment-resistant subpopulation of GBM stem cells (GSC). To identify improved therapeutic possibilities, we combined the EGFR/HER2 inhibitor lapatinib with a novel small molecule, CBL0137, which inhibits FACT (facilitates chromatin transcription), a histone chaperone complex predominantly expressed in undifferentiated cells. Lapatinib and CBL0137 synergistically inhibited the proliferation of patient-derived GBM cells. Compared with non–stem tumor cells (NSTC) enriched from the same specimens, the GSCs were extremely sensitive to CBL0137 monotherapy or FACT knockdown. FACT expression was elevated in GSCs compared with matched NSTCs and decreased in GSCs upon differentiation. Acute exposure of GSCs to CBL0137 increased asymmetric cell division, decreased GSC marker expression, and decreased the capacity of GSCs to form tumor spheres in vitro and to initiate tumors in vivo. Oral administration of CBL0137 to mice bearing orthotopic GBM prolonged their survival. Knockdown of FACT reduced the expression of genes encoding several core stem cell transcription factors (SOX2, OCT4, NANOG, and OLIG2), and FACT occupied the promoters of these genes. FACT expression was elevated in GBM tumors compared with non-neoplastic brain tissues, portended a worse prognosis, and positively correlated with GSC markers and stem cell gene expression signatures. Preferential targeting of GSCs by CBL0137 and synergy with EGFR inhibitors support the development of clinical trials combining these two agents in GBM. Cancer Res; 76(8); 2432–42. ©2016 AACR.

CBL0137 accumulates in brain tissues.

Control arms for Fig. 6 experiments AND Potential future approaches.

Purpose: Investigation of clonal heterogeneity may be key to understanding mechanisms of therapeutic failure in human cancer. However, little is known on the consequences of therapeutic intervention on the clonal composition of solid tumors.Experimental Design: Here, we used 33 single cell–derived subclones generated from five clinical glioblastoma specimens for exploring intra- and interindividual spectra of drug resistance profiles in vitro. In a personalized setting, we explored whether differences in pharmacologic sensitivity among subclones could be employed to predict drug-dependent changes to the clonal composition of tumors.Results: Subclones from individual tumors exhibited a remarkable heterogeneity of drug resistance to a library of potential antiglioblastoma compounds. A more comprehensive intratumoral analysis revealed that stable genetic and phenotypic characteristics of coexisting subclones could be correlated with distinct drug sensitivity profiles. The data obtained from differential drug response analysis could be employed to predict clonal population shifts within the naïve parental tumor in vitro and in orthotopic xenografts. Furthermore, the value of pharmacologic profiles could be shown for establishing rational strategies for individualized secondary lines of treatment.Conclusions: Our data provide a previously unrecognized strategy for revealing functional consequences of intratumor heterogeneity by enabling predictive modeling of treatment-related subclone dynamics in human glioblastoma. Clin Cancer Res; 23(2); 562–74. ©2016 AACR.

Legends for Supplementary Figs. S1-S8 and Supplementary Tables

This file contains detailed materials & methods in addition to the materials & methods section in the main text.

Supplementary Data from VRK1 Is a Synthetic–Lethal Target in VRK2-Deficient Glioblastoma

Supplementary Figure from VRK1 Is a Synthetic–Lethal Target in VRK2-Deficient Glioblastoma

Confirmatory subclone selection experiments applying clinical sample BN035.

conference program

Patient data. AND Drug and compound details. AND Primer sequences for qRT-PCR.

The second International Cancer Stem Cell Conference in Cleveland, Ohio, on September 20–23, 2016, convened 330 attendees from academic, industrial, and clinical organizations. It featured a debate on the concepts and challenges of the cancer stem cells (CSC) as well as CSC-centered scientific sessions on clinical trials, genetics and epigenetics, tumor microenvironment, immune suppression, metastasis, therapeutic resistance, and emerging novel concepts. The conference hosted 35 renowned speakers, 100 posters, 20 short talks, and a preconference workshop. The reported advances of CSC research and therapies fostered new collaborations across national and international borders, and inspired the next generation's young scientists. Cancer Res; 77(19); 5222–7. ©2017 AACR.

Synthetic lethality is a genetic interaction that results in cell death when two genetic deficiencies co-occur but not when either deficiency occurs alone, which can be co-opted for cancer therapeutics. Pairs of paralog genes are among the most straightforward potential synthetic–lethal interactions by virtue of their redundant functions. Here, we demonstrate a paralog-based synthetic lethality by targeting vaccinia-related kinase 1 (VRK1) in glioblastoma (GBM) deficient of VRK2, which is silenced by promoter methylation in approximately two thirds of GBM. Genetic knockdown of VRK1 in VRK2-null or VRK2-methylated cells resulted in decreased activity of the downstream substrate barrier to autointegration factor (BAF), a regulator of post-mitotic nuclear envelope formation. Reduced BAF activity following VRK1 knockdown caused nuclear lobulation, blebbing, and micronucleation, which subsequently resulted in G2–M arrest and DNA damage. The VRK1–VRK2 synthetic–lethal interaction was dependent on VRK1 kinase activity and was rescued by ectopic expression of VRK2. In VRK2-methylated GBM cell line–derived xenograft and patient-derived xenograft models, knockdown of VRK1 led to robust tumor growth inhibition. These results indicate that inhibiting VRK1 kinase activity could be a viable therapeutic strategy in VRK2-methylated GBM.Significance:A paralog synthetic–lethal interaction between VRK1 and VRK2 sensitizes VRK2-methylated glioblastoma to perturbation of VRK1 kinase activity, supporting VRK1 as a drug discovery target in this disease.

This file contains figure legends to supplemental figures S1-S5.

Clonal hematopoiesis of indeterminate potential (CHIP) is a common form of age-related somatic mosaicism that is associated with significant morbidity and mortality. CHIP mutations can be identified in peripheral blood samples sequenced using approaches that cover the whole genome, whole exome or targeted genetic regions; however, differentiating true CHIP mutations from sequencing artifacts and germline variants is a considerable bioinformatic challenge. We present a stepwise method that combines filtering based on sequencing metrics, variant annotation, and novel population-based associations to increase the accuracy of CHIP calls. We apply this approach to ascertain CHIP in ∼550,000 individuals in the UK Biobank complete whole exome cohort and the All of Us Research Program initial whole genome release cohort. CHIP ascertainment on this scale unmasks recurrent artifactual variants and highlights the importance of specialized filtering approaches for several genes includingTET2andASXL1. We show how small changes in filtering parameters can considerably increase CHIP misclassification and reduce the effect size of epidemiological associations. Our high-fidelity call set refines prior population-based associations of CHIP with incident outcomes. For example, the annualized incidence of myeloid malignancy in individuals with small CHIP clones is 0.03%/year, which increases to 0.5%/year amongst individuals with very large CHIP clones. We also find a significantly lower prevalence of CHIP in individuals of self-reported Latino or Hispanic ethnicity in All of Us, highlighting the importance of including diverse populations. The standardization of CHIP calling will increase the fidelity of CHIP epidemiological work and is required for clinical CHIP diagnostic assays.

Historically, anticoagulation has been the primary treatment for acute lower extremity deep venous thrombosis (DVT) with or without thrombolysis. Despite large amounts of clinical research data supporting an ‘open vein hypothesis’, which favours early thrombus removal, clinicians have been hesitant to take this option due to a historically high risk of major bleeding and a few notable studies that failed to show any meaningful benefit. The ATTRACT trial failed to show the benefit of using pharmacomechanical catheter-directed thrombolysis (PCDT) for iliofemoral and femoropopliteal DVT but did result in more bleeding. However, the CaVent study before it revealed a significant reduction in post-thrombotic syndrome (PTS) for patients with iliofemoral and femoral DVT after long-term follow-up past 24 months that grew over time. Since these trials, there have been significant advancements in magnetic resonance and CT venography, intravascular ultrasound (IVUS), venous stenting and thrombectomy catheters meaning there is little to no need for adjunct thrombolytics. Results from ongoing research such as CLEAR-DVT reflect the advances in modern technology.

In multiple types of cancer, an increased frequency in myeloid-derived suppressor cells (MDSC) is associated with worse outcomes and poor therapeutic response. In the glioblastoma (GBM) microenvironment, monocytic (m) MDSCs represent the predominant subset. However, the molecular basis of mMDSC enrichment in the tumor microenvironment compared with granulocytic (g) MDSCs has yet to be determined. Here we performed the first broad epigenetic profiling of MDSC subsets to define underlying cell-intrinsic differences in behavior and found that enhanced gene accessibility of cell adhesion programs in mMDSCs is linked to their tumor-accelerating ability in GBM models upon adoptive transfer. Mouse and human mMDSCs expressed higher levels of integrin β1 and dipeptidyl peptidase-4 (DPP-4) compared with gMDSCs as part of an enhanced cell adhesion signature. Integrin β1 blockade abrogated the tumor-promoting phenotype of mMDSCs and altered the immune profile in the tumor microenvironment, whereas treatment with a DPP-4 inhibitor extended survival in preclinical GBM models. Targeting DPP-4 in mMDSCs reduced pERK signaling and their migration towards tumor cells. These findings uncover a fundamental difference in the molecular basis of MDSC subsets and suggest that integrin β1 and DPP-4 represent putative immunotherapy targets to attenuate myeloid cell-driven immune suppression in GBM. Significance: Epigenetic profiling uncovers cell adhesion programming as a regulator of the tumor-promoting functions of monocytic myeloid-derived suppressor cells in glioblastoma, identifying therapeutic targets that modulate the immune response and suppress tumor growth.

Factors that determine resting energy expenditure (REE) remain under investigation, particularly in persons with a high body mass index (BMI). The accurate estimation of energy expenditure is essential for conducting comprehensive nutrition assessments, planning menus and meals, prescribing weight and chronic disease interventions, and the prevention of malnutrition. This study aimed to: (a) determine the contribution of cardiometabolic biomarkers to the inter-individual variation in REE in persons categorized by BMI; and (b) assess the contribution of these biomarkers in the prediction of REE when persons of varying BMI status were categorized by their glycemic and metabolic syndrome status. Baseline data from 645 adults enrolled in diet intervention trials included REE measured by indirect calorimetry, body composition by dual energy X-ray absorptiometry, anthropometrics, and cardiometabolic biomarkers. Multivariate linear regression modeling was conducted to determine the most parsimonious model that significantly predicted REE by BMI category, metabolic syndrome status, and glycemic status. Modeling with the traditional predictors (age, sex, height, weight) accounted for 58–63% of the inter-individual variance in REE. When including age, sex, height, weight and fat-free mass as covariates, adding TG/HDL to regression modeling accounted for 71–87% of the variance in REE. The finding that TG/HDL is an independent predictor in estimating REE was further confirmed when participants were categorized by metabolic syndrome status and by glycemic status. The clinical utility of calculating the TG/HDL ratio not only aids health care providers in identifying patients with impaired lipid metabolism but can optimize the estimation of REE to better meet therapeutic goals for weight and disease management.

Background and aims The type of fat consumed in animal-based western diets, typically rich in the saturated fat palmitate, has been implicated in cardiometabolic disease risk. In contrast, the most abundant mono- and polyunsaturated fats, more typical in a vegetarian or plant-based diet, potentiate less deleterious effects. This study determined differences in plasma and urine metabolites when switching from omnivorous to vegetarian diet, including metabolites involved in fatty acid utilization. Methods and results A prospective cohort of 38 European (EA) and African American (AA) omnivorous females were matched by age (25.7 ± 5.3y) and BMI (22.4 ± 1.9 kg/m2). Pre-intervention samples were collected while subjects consumed habitual animal-based diet. Changes in metabolites were assessed by ultra-high-performance liquid chromatography-tandem mass spectroscopy (Metabolon, Inc.) upon completing four days of novel vegetarian diet provided by the Vanderbilt Metabolic Kitchen. Changes in several diet-derived metabolites were observed, including increases in compounds derived from soy food metabolism along with decreases in metabolites of xanthine and histidine. Significant changes occurred in metabolites of saturated, monounsaturated and polyunsaturated fatty acids along with significant differences between EA and AA women in changes in plasma concentrations of acylcarnitines, which reflect the completeness of fatty acid oxidation (versus storage). Conclusion These data suggest improvements in fatty acid metabolism (oxidation vs storage), a key factor in energy homeostasis, may be promoted rapidly by adoption of a vegetarian (plant-based) diet. Mechanistic differences in response to diet interventions must be understood to effectively provide protection against the widespread development of obesity and cardiometabolic disease in population subgroups, such as AA women.

Background Many nutrients have powerful immunomodulatory actions with the potential to alter susceptibility to coronavirus disease 2019 (COVID-19) infection, progression to symptoms, likelihood of severe disease, and survival. Objective The aim was to review the latest evidence on how malnutrition across all its forms (under- and overnutrition and micronutrient status) may influence both susceptibility to, and progression of, COVID-19. Methods We synthesized information on 13 nutrition-related components and their potential interactions with COVID-19: overweight, obesity, and diabetes; protein-energy malnutrition; anemia; vitamins A, C, D, and E; PUFAs; iron; selenium; zinc; antioxidants; and nutritional support. For each section we provide: 1) a landscape review of pertinent material; 2) a systematic search of the literature in PubMed and EMBASE databases, including a wide range of preprint servers; and 3) a screen of 6 clinical trial registries. All original research was considered, without restriction to study design, and included if it covered: 1) severe acute respiratory syndrome coronavirus (CoV) 2 (SARS-CoV-2), Middle East respiratory syndrome CoV (MERS-CoV), or SARS-CoV viruses and 2) disease susceptibility or 3) disease progression, and 4) the nutritional component of interest. Searches took place between 16 May and 11 August 2020. Results Across the 13 searches, 2732 articles from PubMed and EMBASE, 4164 articles from the preprint servers, and 433 trials were returned. In the final narrative synthesis, we include 22 published articles, 38 preprint articles, and 79 trials. Conclusions Currently there is limited evidence that high-dose supplements of micronutrients will either prevent severe disease or speed up recovery. However, results of clinical trials are eagerly awaited. Given the known impacts of all forms of malnutrition on the immune system, public health strategies to reduce micronutrient deficiencies and undernutrition remain of critical importance. Furthermore, there is strong evidence that prevention of obesity and type 2 diabetes will reduce the risk of serious COVID-19 outcomes. This review is registered at PROSPERO as CRD42020186194.