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2.
Nature ; 630(8018): 968-975, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38867043

ABSTRACT

Obesity is a leading risk factor for progression and metastasis of many cancers1,2, yet can in some cases enhance survival3-5 and responses to immune checkpoint blockade therapies, including anti-PD-1, which targets PD-1 (encoded by PDCD1), an inhibitory receptor expressed on immune cells6-8. Although obesity promotes chronic inflammation, the role of the immune system in the obesity-cancer connection and immunotherapy remains unclear. It has been shown that in addition to T cells, macrophages can express PD-19-12. Here we found that obesity selectively induced PD-1 expression on tumour-associated macrophages (TAMs). Type I inflammatory cytokines and molecules linked to obesity, including interferon-γ, tumour necrosis factor, leptin, insulin and palmitate, induced macrophage PD-1 expression in an mTORC1- and glycolysis-dependent manner. PD-1 then provided negative feedback to TAMs that suppressed glycolysis, phagocytosis and T cell stimulatory potential. Conversely, PD-1 blockade increased the level of macrophage glycolysis, which was essential for PD-1 inhibition to augment TAM expression of CD86 and major histocompatibility complex I and II molecules and ability to activate T cells. Myeloid-specific PD-1 deficiency slowed tumour growth, enhanced TAM glycolysis and antigen-presentation capability, and led to increased CD8+ T cell activity with a reduced level of markers of exhaustion. These findings show that obesity-associated metabolic signalling and inflammatory cues cause TAMs to induce PD-1 expression, which then drives a TAM-specific feedback mechanism that impairs tumour immune surveillance. This may contribute to increased cancer risk yet improved response to PD-1 immunotherapy in obesity.


Subject(s)
Neoplasms , Obesity , Programmed Cell Death 1 Receptor , Tumor-Associated Macrophages , Animals , Female , Humans , Male , Mice , Antigen Presentation/drug effects , B7-2 Antigen/antagonists & inhibitors , B7-2 Antigen/immunology , B7-2 Antigen/metabolism , CD8-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/metabolism , Cell Line, Tumor , Glycolysis/drug effects , Histocompatibility Antigens Class I/immunology , Histocompatibility Antigens Class II/immunology , Immune Checkpoint Inhibitors/pharmacology , Immune Checkpoint Inhibitors/therapeutic use , Inflammation Mediators/immunology , Inflammation Mediators/metabolism , Lymphocyte Activation , Mechanistic Target of Rapamycin Complex 1/metabolism , Mechanistic Target of Rapamycin Complex 1/antagonists & inhibitors , Mice, Inbred C57BL , Neoplasms/drug therapy , Neoplasms/immunology , Neoplasms/metabolism , Neoplasms/pathology , Obesity/immunology , Obesity/metabolism , Phagocytosis/drug effects , Programmed Cell Death 1 Receptor/metabolism , Programmed Cell Death 1 Receptor/antagonists & inhibitors , Tumor-Associated Macrophages/immunology , Tumor-Associated Macrophages/metabolism , Tumor-Associated Macrophages/drug effects
3.
Elife ; 132024 May 24.
Article in English | MEDLINE | ID: mdl-38787918

ABSTRACT

The tumor microenvironment is a determinant of cancer progression and therapeutic efficacy, with nutrient availability playing an important role. Although it is established that the local abundance of specific nutrients defines the metabolic parameters for tumor growth, the factors guiding nutrient availability in tumor compared to normal tissue and blood remain poorly understood. To define these factors in renal cell carcinoma (RCC), we performed quantitative metabolomic and comprehensive lipidomic analyses of tumor interstitial fluid (TIF), adjacent normal kidney interstitial fluid (KIF), and plasma samples collected from patients. TIF nutrient composition closely resembles KIF, suggesting that tissue-specific factors unrelated to the presence of cancer exert a stronger influence on nutrient levels than tumor-driven alterations. Notably, select metabolite changes consistent with known features of RCC metabolism are found in RCC TIF, while glucose levels in TIF are not depleted to levels that are lower than those found in KIF. These findings inform tissue nutrient dynamics in RCC, highlighting a dominant role of non-cancer-driven tissue factors in shaping nutrient availability in these tumors.


Cancer cells convert nutrients into energy differently compared to healthy cells. This difference in metabolism allows them to grow and divide more quickly and sometimes to migrate to different areas of the body. The environment around cancer cells ­ known as the tumor microenvironment ­ contains a variety of different cells and blood vessels, which are bathed in interstitial fluid. This microenvironment provides nutrients for the cancer cells to metabolize, and therefore influences how well a tumor grows and how it might respond to treatment. Recent advances with techniques such as mass spectrometry, which can measure the chemical composition of a substance, have allowed scientists to measure nutrient levels in the tumor microenvironments of mice. However, it has been more difficult to conduct such studies in humans, as well as to compare the tumor microenvironment to the healthy tissue the tumors arose from. Abbott, Ali, Reinfeld et al. aimed to fill this gap in knowledge by using mass spectrometry to measure the nutrient levels in the tumor microenvironment of 55 patients undergoing surgery to remove kidney tumors. Comparing the type and levels of nutrients in the tumor interstitial fluid, the neighboring healthy kidney and the blood showed that nutrients in the tumor and healthy kidney were more similar to each other than those in the blood. For example, both the tumor and healthy kidney interstitial fluids contained less glucose than the blood. However, the difference between nutrient composition in the tumor and healthy kidney interstitial fluids was insignificant, suggesting that the healthy kidney and its tumor share a similar environment. Taken together, the findings indicate that kidney cancer cells must adapt to the nutrients available in the kidney, rather than changing what nutrients are available in the tissue. Future studies will be required to investigate whether this finding also applies to other types of cancer. A better understanding of how cancer cells adapt to their environments may aid the development of drugs that aim to disrupt the metabolism of tumors.


Subject(s)
Carcinoma, Renal Cell , Kidney Neoplasms , Metabolome , Nutrients , Carcinoma, Renal Cell/metabolism , Carcinoma, Renal Cell/pathology , Humans , Kidney Neoplasms/metabolism , Nutrients/metabolism , Metabolomics/methods , Tumor Microenvironment , Extracellular Fluid/metabolism , Female , Male , Lipidomics
4.
BMC Genomics ; 25(1): 347, 2024 Apr 05.
Article in English | MEDLINE | ID: mdl-38580927

ABSTRACT

BACKGROUND: The ascomycete fungus Anisogramma anomala causes Eastern Filbert Blight (EFB) on hazelnut (Corylus spp.) trees. It is a minor disease on its native host, the American hazelnut (C. americana), but is highly destructive on the commercially important European hazelnut (C. avellana). In North America, EFB has historically limited commercial production of hazelnut to west of the Rocky Mountains. A. anomala is an obligately biotrophic fungus that has not been grown in continuous culture, rendering its study challenging. There is a 15-month latency before symptoms appear on infected hazelnut trees, and only a sexual reproductive stage has been observed. Here we report the sequencing, annotation, and characterization of its genome. RESULTS: The genome of A. anomala was assembled into 108 scaffolds totaling 342,498,352 nt with a GC content of 34.46%. Scaffold N50 was 33.3 Mb and L50 was 5. Nineteen scaffolds with lengths over 1 Mb constituted 99% of the assembly. Telomere sequences were identified on both ends of two scaffolds and on one end of another 10 scaffolds. Flow cytometry estimated the genome size of A. anomala at 370 Mb. The genome exhibits two-speed evolution, with 93% of the assembly as AT-rich regions (32.9% GC) and the other 7% as GC-rich (57.1% GC). The AT-rich regions consist predominantly of repeats with low gene content, while 90% of predicted protein coding genes were identified in GC-rich regions. Copia-like retrotransposons accounted for more than half of the genome. Evidence of repeat-induced point mutation (RIP) was identified throughout the AT-rich regions, and two copies of the rid gene and one of dim-2, the key genes in the RIP mutation pathway, were identified in the genome. Consistent with its homothallic sexual reproduction cycle, both MAT1-1 and MAT1-2 idiomorphs were found. We identified a large suite of genes likely involved in pathogenicity, including 614 carbohydrate active enzymes, 762 secreted proteins and 165 effectors. CONCLUSIONS: This study reveals the genomic structure, composition, and putative gene function of the important pathogen A. anomala. It provides insight into the molecular basis of the pathogen's life cycle and a solid foundation for studying EFB.


Subject(s)
Ascomycota , Corylus , Corylus/genetics , Ascomycota/genetics , Phenotype , Genome Size
5.
J Clin Invest ; 134(8)2024 Apr 15.
Article in English | MEDLINE | ID: mdl-38618956

ABSTRACT

Clear cell renal cell carcinoma (ccRCC) is characterized by dysregulated hypoxia signaling and a tumor microenvironment (TME) highly enriched in myeloid and lymphoid cells. Loss of the von Hippel Lindau (VHL) gene is a critical early event in ccRCC pathogenesis and promotes stabilization of HIF. Whether VHL loss in cancer cells affects immune cells in the TME remains unclear. Using Vhl WT and Vhl-KO in vivo murine kidney cancer Renca models, we found that Vhl-KO tumors were more infiltrated by immune cells. Tumor-associated macrophages (TAMs) from Vhl-deficient tumors demonstrated enhanced in vivo glucose consumption, phagocytosis, and inflammatory transcriptional signatures, whereas lymphocytes from Vhl-KO tumors showed reduced activation and a lower response to anti-programmed cell death 1 (anti-PD-1) therapy in vivo. The chemokine CX3CL1 was highly expressed in human ccRCC tumors and was associated with Vhl deficiency. Deletion of Cx3cl1 in cancer cells decreased myeloid cell infiltration associated with Vhl loss to provide a mechanism by which Vhl loss may have contributed to the altered immune landscape. Here, we identify cancer cell-specific genetic features that drove environmental reprogramming and shaped the tumor immune landscape, with therapeutic implications for the treatment of ccRCC.


Subject(s)
Carcinoma, Renal Cell , Kidney Neoplasms , Animals , Humans , Mice , Carcinogenesis/genetics , Carcinoma, Renal Cell/genetics , Cell Transformation, Neoplastic , Kidney , Kidney Neoplasms/genetics , Tumor Microenvironment , Von Hippel-Lindau Tumor Suppressor Protein/genetics
6.
bioRxiv ; 2024 Apr 08.
Article in English | MEDLINE | ID: mdl-38187626

ABSTRACT

The tumor microenvironment is a determinant of cancer progression and therapeutic efficacy, with nutrient availability playing an important role. Although it is established that the local abundance of specific nutrients defines the metabolic parameters for tumor growth, the factors guiding nutrient availability in tumor compared to normal tissue and blood remain poorly understood. To define these factors in renal cell carcinoma (RCC), we performed quantitative metabolomic and comprehensive lipidomic analyses of tumor interstitial fluid (TIF), adjacent normal kidney interstitial fluid (KIF), and plasma samples collected from patients. TIF nutrient composition closely resembles KIF, suggesting that tissue-specific factors unrelated to the presence of cancer exert a stronger influence on nutrient levels than tumor-driven alterations. Notably, select metabolite changes consistent with known features of RCC metabolism are found in RCC TIF, while glucose levels in TIF are not depleted to levels that are lower than those found in KIF. These findings inform tissue nutrient dynamics in RCC, highlighting a dominant role of non-cancer driven tissue factors in shaping nutrient availability in these tumors.

7.
Genetics ; 227(1)2024 05 07.
Article in English | MEDLINE | ID: mdl-38262680

ABSTRACT

Echinobase (www.echinobase.org) is a model organism knowledgebase serving as a resource for the community that studies echinoderms, a phylum of marine invertebrates that includes sea urchins and sea stars. Echinoderms have been important experimental models for over 100 years and continue to make important contributions to environmental, evolutionary, and developmental studies, including research on developmental gene regulatory networks. As a centralized resource, Echinobase hosts genomes and collects functional genomic data, reagents, literature, and other information for the community. This third-generation site is based on the Xenbase knowledgebase design and utilizes gene-centric pages to minimize the time and effort required to access genomic information. Summary gene pages display gene symbols and names, functional data, links to the JBrowse genome browser, and orthology to other organisms and reagents, and tabs from the Summary gene page contain more detailed information concerning mRNAs, proteins, diseases, and protein-protein interactions. The gene pages also display 1:1 orthologs between the fully supported species Strongylocentrotus purpuratus (purple sea urchin), Lytechinus variegatus (green sea urchin), Patiria miniata (bat star), and Acanthaster planci (crown-of-thorns sea star). JBrowse tracks are available for visualization of functional genomic data from both fully supported species and the partially supported species Anneissia japonica (feather star), Asterias rubens (sugar star), and L. pictus (painted sea urchin). Echinobase serves a vital role by providing researchers with annotated genomes including orthology, functional genomic data aligned to the genomes, and curated reagents and data. The Echinoderm Anatomical Ontology provides a framework for standardizing developmental data across the phylum, and knowledgebase content is formatted to be findable, accessible, interoperable, and reusable by the research community.


Subject(s)
Databases, Genetic , Echinodermata , Animals , Echinodermata/genetics , Genome , Genomics/methods , Sea Urchins/genetics , Knowledge Bases
8.
J Immunol ; 211(4): 563-575, 2023 08 15.
Article in English | MEDLINE | ID: mdl-37341499

ABSTRACT

Activated T cells undergo metabolic reprogramming to meet anabolic, differentiation, and functional demands. Glutamine supports many processes in activated T cells, and inhibition of glutamine metabolism alters T cell function in autoimmune disease and cancer. Multiple glutamine-targeting molecules are under investigation, yet the precise mechanisms of glutamine-dependent CD8 T cell differentiation remain unclear. We show that distinct strategies of glutamine inhibition by glutaminase-specific inhibition with small molecule CB-839, pan-glutamine inhibition with 6-diazo-5-oxo-l-norleucine (DON), or by glutamine-depleted conditions (No Q) produce distinct metabolic differentiation trajectories in murine CD8 T cells. T cell activation with CB-839 treatment had a milder effect than did DON or No Q treatment. A key difference was that CB-839-treated cells compensated with increased glycolytic metabolism, whereas DON and No Q-treated cells increased oxidative metabolism. However, all glutamine treatment strategies elevated CD8 T cell dependence on glucose metabolism, and No Q treatment caused adaptation toward reduced glutamine dependence. DON treatment reduced histone modifications and numbers of persisting cells in adoptive transfer studies, but those T cells that remained could expand normally upon secondary Ag encounter. In contrast, No Q-treated cells persisted well yet demonstrated decreased secondary expansion. Consistent with reduced persistence, CD8 T cells activated in the presence of DON had reduced ability to control tumor growth and reduced tumor infiltration in adoptive cell therapy. Overall, each approach to inhibit glutamine metabolism confers distinct effects on CD8 T cells and highlights that targeting the same pathway in different ways can elicit opposing metabolic and functional outcomes.


Subject(s)
Diazooxonorleucine , Neoplasms , Animals , Mice , Diazooxonorleucine/pharmacology , Glutamine/metabolism , Neoplasms/therapy , Neoplasms/metabolism , CD8-Positive T-Lymphocytes/metabolism
9.
Genetics ; 224(1)2023 05 04.
Article in English | MEDLINE | ID: mdl-36755307

ABSTRACT

Xenbase (https://www.xenbase.org/), the Xenopus model organism knowledgebase, is a web-accessible resource that integrates the diverse genomic and biological data from research on the laboratory frogs Xenopus laevis and Xenopus tropicalis. The goal of Xenbase is to accelerate discovery and empower Xenopus research, to enhance the impact of Xenopus research data, and to facilitate the dissemination of these data. Xenbase also enhances the value of Xenopus data through high-quality curation, data integration, providing bioinformatics tools optimized for Xenopus experiments, and linking Xenopus data to human data, and other model organisms. Xenbase also plays an indispensable role in making Xenopus data interoperable and accessible to the broader biomedical community in accordance with FAIR principles. Xenbase provides annotated data updates to organizations such as NCBI, UniProtKB, Ensembl, the Gene Ontology consortium, and most recently, the Alliance of Genomic Resources, a common clearing house for data from humans and model organisms. This article provides a brief overview of key and recently added features of Xenbase. New features include processing of Xenopus high-throughput sequencing data from the NCBI Gene Expression Omnibus; curation of anatomical, physiological, and expression phenotypes with the newly created Xenopus Phenotype Ontology; Xenopus Gene Ontology annotations; new anatomical drawings of the Normal Table of Xenopus development; and integration of the latest Xenopus laevis v10.1 genome annotations. Finally, we highlight areas for future development at Xenbase as we continue to support the Xenopus research community.


Subject(s)
Databases, Genetic , Genomics , Animals , Humans , Xenopus laevis/genetics , Xenopus/genetics , Computational Biology
10.
BMC Med Educ ; 22(1): 821, 2022 Nov 29.
Article in English | MEDLINE | ID: mdl-36447223

ABSTRACT

BACKGROUND: Students with developed self-regulated learning (SRL) skills demonstrate an ability to set individualized educational goals, select optimal learning strategies for reaching these goals, and reflect on overall progress. The primary aims of this study were to investigate first-year medical students' perceived utility of a self-regulated learning-informed intervention and to assess the impact of its implementation on students' intended use of SRL throughout medical school. METHODS: A two-part educational intervention focused on SRL skill development was carried out at Harvard Medical School during the start of the 2021 academic year. For the first component of the intervention, 169 first-year medical students engaged in an interactive class session structured around SRL concept videos, a brief lecture, small group discussions and individual reflection. Students completed pre- and post-intervention surveys which inquired about learners' current and anticipated application of SRL skills. During the second component of the intervention, 15 first-year medical students participated in a set of one-on-one academic SRL coaching sessions. All coaching participants completed follow-up semi-structured interviews. RESULTS: A statistically significant increase was observed between students' use of skills in all domains of self-regulated learning prior to the intervention and their anticipated use of these skills following the intervention. Prior to the intervention, 60.1% (n = 92) of students reported utilizing evidence-based learning strategies, compared to 92.8% (n = 142) of students (p < 0.001) who anticipated applying this SRL skills at the completion of the classroom session. Six core themes emerged from qualitative analysis of the post-intervention survey including learning plan development, accountability and progress tracking, goals for growth, engagement through active learning, routine reflection, and adapting to the curriculum. CONCLUSIONS: Both classroom-based learning sessions and one-on-one academic coaching programs are feasible approaches for encouraging the use of self-regulated learning techniques in the preclinical setting.


Subject(s)
Mentoring , Students, Medical , Humans , Schools, Medical , Learning , Problem-Based Learning
11.
Nat Microbiol ; 7(9): 1348-1360, 2022 09.
Article in English | MEDLINE | ID: mdl-35995841

ABSTRACT

Urinary tract infections are among the most common human bacterial infections and place a significant burden on healthcare systems due to associated morbidity, cost and antibiotic use. Despite being a facultative anaerobe, uropathogenic Escherichia coli, the primary cause of urinary tract infections, requires aerobic respiration to establish infection in the bladder. Here, by combining bacterial genetics with cell culture and murine models of infection, we demonstrate that the widely conserved respiratory quinol oxidase cytochrome bd is required for intracellular infection of urothelial cells. Through a series of genetic, biochemical and functional assays, we show that intracellular oxygen scavenging by cytochrome bd alters mitochondrial physiology by reducing the efficiency of mitochondrial respiration, stabilizing the hypoxia-inducible transcription factor HIF-1 and promoting a shift towards aerobic glycolysis. This bacterially induced rewiring of host metabolism antagonizes apoptosis, thereby protecting intracellular bacteria from urothelial cell exfoliation and preserving their replicative niche. These results reveal the metabolic basis for intracellular bacterial pathogenesis during urinary tract infection and identify subversion of mitochondrial metabolism as a bacterial strategy to facilitate persistence within the urinary tract.


Subject(s)
Escherichia coli Infections , Urinary Tract Infections , Urinary Tract , Uropathogenic Escherichia coli , Animals , Cytochromes , Humans , Mice
12.
BMC Cancer ; 22(1): 497, 2022 May 06.
Article in English | MEDLINE | ID: mdl-35513776

ABSTRACT

BACKGROUND: Current cancer immunotherapies have made tremendous impacts but generally lack high response rates, especially in ovarian cancer. New therapies are needed to provide increased benefits. One understudied approach is to target the large population of immunosuppressive tumor-associated macrophages (TAMs). Using inducible transgenic mice, we recently reported that upregulating nuclear factor-kappaB (NF-κB) signaling in TAMs promotes the M1, anti-tumor phenotype and limits ovarian cancer progression. We also developed a mannose-decorated polymeric nanoparticle system (MnNPs) to preferentially deliver siRNA payloads to M2, pro-tumor macrophages in vitro. In this study, we tested a translational strategy to repolarize ovarian TAMs via MnNPs loaded with siRNA targeting the inhibitor of NF-κB alpha (IκBα) using mouse models of ovarian cancer. METHODS: We evaluated treatment with MnNPs loaded with IκBα siRNA (IκBα-MnNPs) or scrambled siRNA in syngeneic ovarian cancer models. ID8 tumors in C57Bl/6 mice were used to evaluate consecutive-day treatment of late-stage disease while TBR5 tumors in FVB mice were used to evaluate repetitive treatments in a faster-developing disease model. MnNPs were evaluated for biodistribution and therapeutic efficacy in both models. RESULTS: Stimulation of NF-κB activity and repolarization to an M1 phenotype via IκBα-MnNP treatment was confirmed using cultured luciferase-reporter macrophages. Delivery of MnNPs with fluorescent payloads (Cy5-MnNPs) to macrophages in the solid tumors and ascites was confirmed in both tumor models. A three consecutive-day treatment of IκBα-MnNPs in the ID8 model validated a shift towards M1 macrophage polarization in vivo. A clear therapeutic effect was observed with biweekly treatments over 2-3 weeks in the TBR5 model where significantly reduced tumor burden was accompanied by changes in immune cell composition, indicative of reduced immunosuppressive tumor microenvironment. No evidence of toxicity associated with MnNP treatment was observed in either model. CONCLUSIONS: In mouse models of ovarian cancer, MnNPs were preferentially associated with macrophages in ascites fluid and solid tumors. Evidence of macrophage repolarization, increased inflammatory cues, and reduced tumor burden in IκBα-MnNP-treated mice indicate beneficial outcomes in models of established disease. We have provided evidence of a targeted, TAM-directed approach to increase anti-tumor immunity in ovarian cancer with strong translational potential for future clinical studies.


Subject(s)
Nanoparticles , Ovarian Neoplasms , Animals , Ascites , Carcinoma, Ovarian Epithelial , Disease Models, Animal , Female , Humans , Mannose/pharmacology , Mannose/therapeutic use , Mice , NF-KappaB Inhibitor alpha , NF-kappa B/metabolism , Ovarian Neoplasms/drug therapy , Ovarian Neoplasms/pathology , RNA, Small Interfering/pharmacology , Tissue Distribution , Tumor Microenvironment
13.
BMC Bioinformatics ; 23(1): 99, 2022 Mar 22.
Article in English | MEDLINE | ID: mdl-35317743

ABSTRACT

BACKGROUND: Ontologies of precisely defined, controlled vocabularies are essential to curate the results of biological experiments such that the data are machine searchable, can be computationally analyzed, and are interoperable across the biomedical research continuum. There is also an increasing need for methods to interrelate phenotypic data easily and accurately from experiments in animal models with human development and disease. RESULTS: Here we present the Xenopus phenotype ontology (XPO) to annotate phenotypic data from experiments in Xenopus, one of the major vertebrate model organisms used to study gene function in development and disease. The XPO implements design patterns from the Unified Phenotype Ontology (uPheno), and the principles outlined by the Open Biological and Biomedical Ontologies (OBO Foundry) to maximize interoperability with other species and facilitate ongoing ontology management. Constructed in Web Ontology Language (OWL) the XPO combines the existing uPheno library of ontology design patterns with additional terms from the Xenopus Anatomy Ontology (XAO), the Phenotype and Trait Ontology (PATO) and the Gene Ontology (GO). The integration of these different ontologies into the XPO enables rich phenotypic curation, whilst the uPheno bridging axioms allows phenotypic data from Xenopus experiments to be related to phenotype data from other model organisms and human disease. Moreover, the simple post-composed uPheno design patterns facilitate ongoing XPO development as the generation of new terms and classes of terms can be substantially automated. CONCLUSIONS: The XPO serves as an example of current best practices to help overcome many of the inherent challenges in harmonizing phenotype data between different species. The XPO currently consists of approximately 22,000 terms and is being used to curate phenotypes by Xenbase, the Xenopus Model Organism Knowledgebase, forming a standardized corpus of genotype-phenotype data that can be directly related to other uPheno compliant resources.


Subject(s)
Biological Ontologies , Animals , Gene Ontology , Humans , Phenotype , Xenopus laevis
14.
Cell Mol Immunol ; 19(1): 46-58, 2022 01.
Article in English | MEDLINE | ID: mdl-34239083

ABSTRACT

In 2011, Hanahan and Weinberg added "Deregulating Cellular Energetics" and "Avoiding Immune Destruction" to the six previous hallmarks of cancer. Since this seminal paper, there has been a growing consensus that these new hallmarks are not mutually exclusive but rather interdependent. The following review summarizes how founding genetic events for tumorigenesis ultimately increase tumor cell glycolysis, which not only supports the metabolic demands of malignancy but also provides an immunoprotective niche, promoting malignant cell proliferation, maintenance and progression. The mechanisms by which altered metabolism contributes to immune impairment are multifactorial: (1) the metabolic demands of proliferating tumor cells and activated immune cells are similar, thus creating a situation where immune cells may be in competition for key nutrients; (2) the metabolic byproducts of aerobic glycolysis directly inhibit antitumor immunity while promoting a regulatory immune phenotype; and (3) the gene programs associated with the upregulation of glycolysis also result in the generation of immunosuppressive cytokines and metabolites. From this perspective, we shed light on important considerations for the development of new classes of agents targeting cancer metabolism. These types of therapies can impair tumor growth but also pose a significant risk of stifling antitumor immunity.


Subject(s)
Neoplasms , Citric Acid Cycle , Glycolysis/physiology , Humans , Neoplasms/metabolism
15.
Nat Chem Biol ; 18(4): 360-367, 2022 04.
Article in English | MEDLINE | ID: mdl-34857958

ABSTRACT

Cancer cells have long been recognized to exhibit unique bioenergetic requirements. The apoptolidin family of glycomacrolides are distinguished by their selective cytotoxicity towards oncogene-transformed cells, yet their molecular mechanism remains uncertain. We used photoaffinity analogs of the apoptolidins to identify the F1 subcomplex of mitochondrial ATP synthase as the target of apoptolidin A. Cryogenic electron microscopy (cryo-EM) of apoptolidin and ammocidin-ATP synthase complexes revealed a novel shared mode of inhibition that was confirmed by deep mutational scanning of the binding interface to reveal resistance mutations which were confirmed using CRISPR-Cas9. Ammocidin A was found to suppress leukemia progression in vivo at doses that were tolerated with minimal toxicity. The combination of cellular, structural, mutagenesis, and in vivo evidence defines the mechanism of action of apoptolidin family glycomacrolides and establishes a path to address oxidative phosphorylation-dependent cancers.


Subject(s)
Leukemia , Neoplasms , Adenosine Triphosphate , Humans , Leukemia/drug therapy , Macrolides , Mitochondrial Proton-Translocating ATPases/chemistry , Neoplasms/drug therapy
16.
Drug Alcohol Rev ; 41(2): 377-385, 2022 02.
Article in English | MEDLINE | ID: mdl-34250645

ABSTRACT

INTRODUCTION: This study describes the legal recreational cannabis market across Canada over the 2 years following legalisation. We compared changes in access to the legal cannabis retail market for all provinces and territories (jurisdictions) in Canada and explored differences between jurisdictions. METHODS: We collected data for all legal cannabis stores in Canada over five time periods following legalisation in October 2018. We examined the following measures by jurisdiction and retail model (public vs. private operation): absolute and per capita store numbers, hours of operation and store access across neighbourhoods. RESULTS: Two years following legalisation, there were a total of 1183 legal cannabis stores open across Canada (3.7 stores per 100 000 individuals aged 15+). There was wide variation between jurisdictions in access to retail stores, with the lowest stores per capita in Quebec and Ontario (0.6 and 1.6 per 100 000), and the highest in Alberta and Yukon (14.3 per 100 000 in both). Jurisdictions with private retail models had more stores (4.8 vs. 1.0 per 100 000), held greater median weekly hours (80 vs. 69) and experienced greater store growth over time compared to public models. After adjusting for confounders, there were 1.96 times (95% confidence intervals: 1.84, 2.09) more cannabis stores within 1000 m of the lowest- compared to the highest-income quintile neighbourhoods. DISCUSSION AND CONCLUSIONS: While access to the recreational cannabis retail market has increased following legalisation, there is substantial variation in access between jurisdictions and evidence of concentration in lower-income neighbourhoods. These differences may contribute to disparities in cannabis use and harms.


Subject(s)
Cannabis , Adolescent , Canada , Humans , Legislation, Drug , Marketing , Ontario , Yukon Territory
17.
Nucleic Acids Res ; 50(D1): D970-D979, 2022 01 07.
Article in English | MEDLINE | ID: mdl-34791383

ABSTRACT

Echinobase (www.echinobase.org) is a third generation web resource supporting genomic research on echinoderms. The new version was built by cloning the mature Xenopus model organism knowledgebase, Xenbase, refactoring data ingestion pipelines and modifying the user interface to adapt to multispecies echinoderm content. This approach leveraged over 15 years of previous database and web application development to generate a new fully featured informatics resource in a single year. In addition to the software stack, Echinobase uses the private cloud and physical hosts that support Xenbase. Echinobase currently supports six echinoderm species, focused on those used for genomics, developmental biology and gene regulatory network analyses. Over 38 000 gene pages, 18 000 publications, new improved genome assemblies, JBrowse genome browser and BLAST + services are available and supported by the development of a new echinoderm anatomical ontology, uniformly applied formal gene nomenclature, and consistent orthology predictions. A novel feature of Echinobase is integrating support for multiple, disparate species. New genomes from the diverse echinoderm phylum will be added and supported as data becomes available. The common code development design of the integrated knowledgebases ensures parallel improvements as each resource evolves. This approach is widely applicable for developing new model organism informatics resources.


Subject(s)
Databases, Genetic , Echinodermata/genetics , Gene Regulatory Networks , Genome , User-Computer Interface , Animals , Echinodermata/classification , Genomics , Internet , Knowledge Bases , Molecular Sequence Annotation , Phylogeny , Xenopus/genetics
18.
Biosens Bioelectron ; 198: 113774, 2022 Feb 15.
Article in English | MEDLINE | ID: mdl-34823962

ABSTRACT

Biointegrative information processing systems offer a great advantage to autonomous biodevices, as their capacity for biological computation provides the ability to sense the state of more complex environments and better integrate with downstream biological regulation systems. Deoxyribozymes (DNAzymes) and aptamers are of interest to such computational biosensing systems due to the enzymatic properties of DNAzymes and the ligand-inducible conformational structures of aptamers. Herein, we describe a novel method for providing ligand-responsive allosteric control to a DNAzyme using an RNA aptamer. We designed a NOT-logic-compliant E6 DNAzyme to be complementary to an RNA aptamer targeting theophylline, such that the aptamer competitively interacted with either theophylline or the DNAzyme, and disabled the DNAzyme only when theophylline concentration was below a given threshold. Out of our seven designed "complexing aptazymes," three demonstrated effective theophylline-responsive allosteric regulation (2.84 ± 3.75%, 4.97 ± 2.92%, and 8.91 ± 4.19% activity in the absence of theophylline; 46.29 ± 3.36%, 50.70 ± 10.15%, and 61.26 ± 6.18% activity in the presence of theophylline). Moreover, the same three complexing aptazymes also demonstrated the ability to semi-quantitatively determine the concentration of theophylline present in solution, successfully discriminating between therapeutically ineffective (<20 µM), safe (20-100 µM), and toxic (>100 µM) theophylline concentrations. Our method of using an RNA aptamer for ligand-responsive allosteric control of a DNAzyme expands the way aptamers can be configured for biosensing, and suggests a pathway for embedding DNAzymes to provide enhanced information processing and control of biological systems.


Subject(s)
Aptamers, Nucleotide , Biosensing Techniques , DNA, Catalytic , Ligands , Theophylline
19.
J Immunol ; 207(12): 3122-3130, 2021 12 15.
Article in English | MEDLINE | ID: mdl-34772698

ABSTRACT

Although obesity can promote cancer, it may also increase immunotherapy efficacy in what has been termed the obesity-immunotherapy paradox. Mechanisms of this effect are unclear, although obesity alters key inflammatory cytokines and can promote an inflammatory state that may modify tumor-infiltrating lymphocytes and tumor-associated macrophage populations. To identify mechanisms by which obesity affects antitumor immunity, we examined changes in cell populations and the role of the proinflammatory adipokine leptin in immunotherapy. Single-cell RNAseq demonstrated that obesity decreased tumor-infiltrating lymphocyte frequencies, and flow cytometry confirmed altered macrophage phenotypes with lower expression of inducible NO synthase and MHC class II in tumors of obese animals. When treated with anti-programmed cell death protein 1 (PD-1) Abs, however, obese mice had a greater absolute decrease in tumor burden than lean mice and a repolarization of the macrophages to inflammatory M1-like phenotypes. Mechanistically, leptin is a proinflammatory adipokine that is induced in obesity and may mediate enhanced antitumor immunity in obesity. To directly test the effect of leptin on tumor growth and antitumor immunity, we treated lean mice with leptin and observed tumors over time. Treatment with leptin, acute or chronic, was sufficient to enhance antitumor efficacy similar to anti-PD-1 checkpoint therapy. Further, leptin and anti-PD-1 cotreatment may enhance antitumor effects consistent with an increase in M1-like tumor-associated macrophage frequency compared with non-leptin-treated mice. These data demonstrate that obesity has dual effects in cancer through promotion of tumor growth while simultaneously enhancing antitumor immunity through leptin-mediated macrophage reprogramming.


Subject(s)
Neoplasms , Tumor-Associated Macrophages , Animals , Cell Line, Tumor , Immunologic Factors/pharmacology , Immunotherapy , Lymphocytes, Tumor-Infiltrating , Mice , Neoplasms/therapy , Obesity/metabolism
20.
JAMA Netw Open ; 4(11): e2132397, 2021 11 01.
Article in English | MEDLINE | ID: mdl-34726744

ABSTRACT

Importance: Recent immigrants face unique cultural and logistical challenges that differ from those of long-standing residents, which may influence the type of care they receive at the end of life. Objective: To compare places of care among recent immigrants and long-standing residents in Canada in the last 90 days of life. Design, Setting, and Participants: This population-based retrospective cohort study used linked health administrative data on individuals from Ontario, Canada, who died between January 1, 2013, and December 31, 2016, extracted on February 26, 2020. Individuals were categorized by immigration status: recent immigrants (since 1985) and long-standing residents. Data were analyzed from December 27, 2019, to February 26, 2020. Exposures: All decedents who immigrated to Canada between 1985 and 2016 were classified as recent immigrants. Subgroup analyses assessed the association of region of origin. Main Outcomes and Measures: The main outcome was place of care, including institutional and noninstitutional settings, in the last 90 days of life. Descriptive statistics were used to compare characteristics and health service utilization among recent immigrants and long-standing residents. Negative binomial regression models estimated the rate ratios (RR) of using acute care and long-term care in the last 90 days of life. Results: A total of 376 617 deceased individuals (median [IQR] age, 80 [68-88] years; 187 439 [49.8%] women and 189 178 [50.2%] men) were identified, among whom 22 423 (6.0%) were recent immigrants; recent immigrants were younger than long-standing residents (median [IQR] age, 76 [60-85] years vs 81 [69-88] years; P < .001), more likely to be living in lower income neighborhoods (12 357 immigrants [55.1%] vs 166 017 long-standing residents [46.9%] in the lower 2 income quintiles; P < .001), and had a higher Charlson Index score (score ≥5, 6294 immigrants [28.1%] vs 74 809 long-standing residents [21.1%]; P < .001). In the last 90 days of life, recent immigrants spent more days in intensive care units than long-standing residents (mean [SD], 2.64 [8.73] days vs 1.47 [5.70] days; P < .001), while long-standing residents spent more days using long-term care than recent immigrants (mean [SD], 19.49 [35.81] days vs 10.45 [27.42] days; P < .001). Being a recent immigrant was associated with a greater likelihood of acute inpatient care use (RR, 1.21; 95% CI, 1.18-1.24) and lower likelihood of long-term care use (RR, 0.66; 95% CI, 0.63-0.70), after adjusting for covariates. Conclusions and Relevance: These findings suggest that at the end of life, recent immigrants were significantly more likely to receive inpatient and intensive care unit services and die in acute care settings compared with long-standing residents. Further research is needed to examine differences in care preference and disparities for immigrant groups of different origins.


Subject(s)
Critical Care/statistics & numerical data , Emergency Service, Hospital/statistics & numerical data , Emigrants and Immigrants/statistics & numerical data , Terminal Care/statistics & numerical data , Aged , Aged, 80 and over , Female , Humans , Intensive Care Units/statistics & numerical data , Male , Middle Aged , Ontario , Retrospective Studies
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