RESUMO
In humans, defects in leucine catabolism cause a variety of inborn errors in metabolism. Here, we use Caenorhabditis elegans to investigate the impact of mutations in mccc-1, an enzyme that functions in leucine breakdown. Through untargeted metabolomic and transcriptomic analyses we find extensive metabolic rewiring that helps to detoxify leucine breakdown intermediates via conversion into previously undescribed metabolites and to synthesize mevalonate, an essential metabolite. We also find that the leucine breakdown product 3,3-hydroxymethylbutyrate (HMB), commonly used as a human muscle-building supplement, is toxic to C. elegans and that bacteria modulate this toxicity. Unbiased genetic screens revealed interactions between the host and microbe, where components of bacterial pyrimidine biosynthesis mitigate HMB toxicity. Finally, upregulated ketone body metabolism genes in mccc-1 mutants provide an alternative route for biosynthesis of the mevalonate precursor 3-hydroxy-3-methylglutaryl-CoA. Our work demonstrates that a complex host-bacteria interplay rewires metabolism to allow host survival when leucine catabolism is perturbed.
RESUMO
Multiple Myeloma (MM) remains incurable despite advances in treatment options. Although tumor subtypes and specific DNA abnormalities are linked to worse prognosis, the impact of immune dysfunction on disease emergence and/or treatment sensitivity remains unclear. We established a harmonized consortium to generate an Immune Atlas of MM aimed at informing disease etiology, risk stratification, and potential therapeutic strategies. We generated a transcriptome profile of 1,149,344 single cells from the bone marrow of 263 newly diagnosed patients enrolled in the CoMMpass study and characterized immune and hematopoietic cell populations. Associating cell abundances and gene expression with disease progression revealed the presence of a proinflammatory immune senescence-associated secretory phenotype in rapidly progressing patients. Furthermore, signaling analyses suggested active intercellular communication involving APRIL-BCMA, potentially promoting tumor growth and survival. Finally, we demonstrate that integrating immune cell levels with genetic information can significantly improve patient stratification.
RESUMO
The landscape of non-coding mutations in cancer progression and immune evasion is largely unexplored. Here, we identify transcrptome-wide somatic and germline 3' untranslated region (3'-UTR) variants from 375 gastric cancer patients from The Cancer Genome Atlas. By performing gene expression quantitative trait loci (eQTL) and immune landscape QTL (ilQTL) analysis, we discover 3'-UTR variants with cis effects on expression and immune landscape phenotypes, such as immune cell infiltration and T cell receptor diversity. Using a massively parallel reporter assay, we distinguish between causal and correlative effects of 3'-UTR eQTLs in immune-related genes. Our approach identifies numerous 3'-UTR eQTLs and ilQTLs, providing a unique resource for the identification of immunotherapeutic targets and biomarkers. A prioritized ilQTL variant signature predicts response to immunotherapy better than standard-of-care PD-L1 expression in independent patient cohorts, showcasing the untapped potential of non-coding mutations in cancer.
Assuntos
Regiões 3' não Traduzidas , Locos de Características Quantitativas , Neoplasias Gástricas , Evasão Tumoral , Humanos , Neoplasias Gástricas/genética , Neoplasias Gástricas/imunologia , Evasão Tumoral/genética , Regiões 3' não Traduzidas/genética , Regulação Neoplásica da Expressão Gênica , Mutação , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Imunoterapia/métodos , Feminino , MasculinoRESUMO
BACKGROUND: There is a paucity of effective systemic therapy options for patients with advanced, chemotherapy-refractory colorectal cancer. We aimed to evaluate the efficacy and safety of fruquintinib, a highly selective and potent oral inhibitor of vascular endothelial growth factor receptors (VEGFRs) 1, 2, and 3, in patients with heavily pretreated metastatic colorectal cancer. METHODS: We conducted an international, randomised, double-blind, placebo-controlled, phase 3 study (FRESCO-2) at 124 hospitals and cancer centres across 14 countries. We included patients aged 18 years or older (≥20 years in Japan) with histologically or cytologically documented metastatic colorectal adenocarcinoma who had received all current standard approved cytotoxic and targeted therapies and progressed on or were intolerant to trifluridine-tipiracil or regorafenib, or both. Eligible patients were randomly assigned (2:1) to receive fruquintinib (5 mg capsule) or matched placebo orally once daily on days 1-21 in 28-day cycles, plus best supportive care. Stratification factors were previous trifluridine-tipiracil or regorafenib, or both, RAS mutation status, and duration of metastatic disease. Patients, investigators, study site personnel, and sponsors, except for selected sponsor pharmacovigilance personnel, were masked to study group assignments. The primary endpoint was overall survival, defined as the time from randomisation to death from any cause. A non-binding futility analysis was done when approximately one-third of the expected overall survival events had occurred. Final analysis occurred after 480 overall survival events. This study is registered with ClinicalTrials.gov, NCT04322539, and EudraCT, 2020-000158-88, and is ongoing but not recruiting. FINDINGS: Between Aug 12, 2020, and Dec 2, 2021, 934 patients were assessed for eligibility and 691 were enrolled and randomly assigned to receive fruquintinib (n=461) or placebo (n=230). Patients had received a median of 4 lines (IQR 3-6) of previous systemic therapy for metastatic disease, and 502 (73%) of 691 patients had received more than 3 lines. Median overall survival was 7·4 months (95% CI 6·7-8·2) in the fruquintinib group versus 4·8 months (4·0-5·8) in the placebo group (hazard ratio 0·66, 95% CI 0·55-0·80; p<0·0001). Grade 3 or worse adverse events occurred in 286 (63%) of 456 patients who received fruquintinib and 116 (50%) of 230 who received placebo; the most common grade 3 or worse adverse events in the fruquintinib group included hypertension (n=62 [14%]), asthenia (n=35 [8%]), and hand-foot syndrome (n=29 [6%]). There was one treatment-related death in each group (intestinal perforation in the fruquintinib group and cardiac arrest in the placebo group). INTERPRETATION: Fruquintinib treatment resulted in a significant and clinically meaningful benefit in overall survival compared with placebo in patients with refractory metastatic colorectal cancer. These data support the use of fruquintinib as a global treatment option for patients with refractory metastatic colorectal cancer. Ongoing analysis of the quality of life data will further establish the clinical benefit of fruquintinib in this patient population. FUNDING: HUTCHMED.
Assuntos
Neoplasias do Colo , Neoplasias Colorretais , Neoplasias Retais , Humanos , Trifluridina/efeitos adversos , Fator A de Crescimento do Endotélio Vascular , Qualidade de Vida , Neoplasias Retais/tratamento farmacológico , Método Duplo-Cego , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversosRESUMO
In humans, mutations in D-2-hydroxyglutarate (D-2HG) dehydrogenase (D2HGDH) result in D-2HG accumulation, delayed development, seizures, and ataxia. While the mechanisms of 2HG-associated diseases have been studied extensively, the endogenous metabolism of D-2HG remains unclear in any organism. Here, we find that, in Caenorhabditis elegans, D-2HG is produced in the propionate shunt, which is transcriptionally activated when flux through the canonical, vitamin B12-dependent propionate breakdown pathway is perturbed. Loss of the D2HGDH ortholog, dhgd-1, results in embryonic lethality, mitochondrial defects, and the up-regulation of ketone body metabolism genes. Viability can be rescued by RNAi of hphd-1, which encodes the enzyme that produces D-2HG or by supplementing either vitamin B12 or the ketone bodies 3-hydroxybutyrate (3HB) and acetoacetate (AA). Altogether, our findings support a model in which C. elegans relies on ketone bodies for energy when vitamin B12 levels are low and in which a loss of dhgd-1 causes lethality by limiting ketone body production.
Assuntos
Caenorhabditis elegans , Propionatos , Humanos , Animais , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Propionatos/metabolismo , Vitamina B 12 , CetonasRESUMO
Surufatinib, is a potent inhibitor of vascular endothelial growth factor receptors 1-3; fibroblast growth factor receptor-1; colony-stimulating factor 1 receptor. This Phase 1/1b escalation/expansion study in US patients with solid tumors evaluated 5 once daily (QD) surufatinib doses (3 + 3 design) to identify maximum tolerated dose (MTD), recommended Phase 2 dose (RP2D), and evaluate safety and efficacy at the RP2D in 4 disease-specific expansion cohorts including pancreatic neuroendocrine tumors [pNET] and extrapancreatic NETs [epNET]. MTD and RP2D were 300 mg QD (escalation [n = 35]); 5 patients (15.6%) (Dose Limiting Toxicity [DLT] Evaluable Set [n = 32]) had DLTs. Pharmacokinetics were dose proportional. Estimated progression-free survival (PFS) rates at 11 months were 57.4% (95% confidence interval [CI]: 28.7, 78.2) and 51.1% (95% CI: 12.8, 80.3) for pNET and epNET expansion cohorts, respectively. Median PFS was 15.2 (95% CI: 5.2, not evaluable) and 11.5 (95% CI: 6.5,11.5) months. Response rates were 18.8% and 6.3%. The most frequent treatment-emergent adverse events (both cohorts) were fatigue (46.9%), hypertension (43.8%), proteinuria (37.5%), diarrhea (34.4%). Pharmacokinetics, safety, and antitumor efficacy of 300 mg QD oral surufatinib in US patients with pNETs and epNETs are consistent with previously reported studies in China and may support applicability of earlier surufatinib studies in US patients. Clinical trial registration: Clinicaltrials.gov NCT02549937.
Assuntos
Neoplasias , Tumores Neuroectodérmicos Primitivos , Tumores Neuroendócrinos , Humanos , Tumores Neuroendócrinos/tratamento farmacológico , Tumores Neuroendócrinos/patologia , Receptor 1 de Fatores de Crescimento do Endotélio Vascular , Fator A de Crescimento do Endotélio Vascular , Neoplasias/patologia , Inibidores de Proteínas Quinases/efeitos adversos , Tumores Neuroectodérmicos Primitivos/induzido quimicamente , Dose Máxima TolerávelRESUMO
Chromatin modifiers and transcriptional cofactors (collectively referred to as CFs) work with DNA-binding transcription factors (TFs) to regulate gene expression. In multicellular eukaryotes, distinct tissues each execute their own gene expression program for accurate differentiation and subsequent functionality. While the function of TFs in differential gene expression has been studied in detail in many systems, the contribution of CFs has remained less explored. Here, we uncovered the contributions of CFs to gene regulation in the Caenorhabditis elegans intestine. We first annotated 366 CFs encoded by the C. elegans genome and assembled a library of 335 RNAi clones. Using this library, we analyzed the effects of individually depleting these CFs on the expression of 19 fluorescent transcriptional reporters in the intestine and identified 216 regulatory interactions. We found that different CFs regulate different promoters, and that both essential and intestinally expressed CFs have the greatest effects on promoter activity. We did not find all members of CF complexes acting on the same set of reporters but instead found diversity in the promoter targets of each complex component. Finally, we found that previously identified activation mechanisms for the acdh-1 promoter use different CFs and TFs. Overall, we demonstrate that CFs function specifically rather than ubiquitously at intestinal promoters and provide an RNAi resource for reverse genetic screens.
Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Animais , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Intestinos , Regulação da Expressão GênicaRESUMO
Metabolism is controlled to ensure organismal development and homeostasis. Several mechanisms regulate metabolism, including allosteric control and transcriptional regulation of metabolic enzymes and transporters. So far, metabolism regulation has mostly been described for individual genes and pathways, and the extent of transcriptional regulation of the entire metabolic network remains largely unknown. Here, we find that three-quarters of all metabolic genes are transcriptionally regulated in the nematode Caenorhabditis elegans. We find that many annotated metabolic pathways are coexpressed, and we use gene expression data and the iCEL1314 metabolic network model to define coregulated subpathways in an unbiased manner. Using a large gene expression compendium, we determine the conditions where subpathways exhibit strong coexpression. Finally, we develop "WormClust," a web application that enables a gene-by-gene query of genes to view their association with metabolic (sub)-pathways. Overall, this study sheds light on the ubiquity of transcriptional regulation of metabolism and provides a blueprint for similar studies in other organisms, including humans.
Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Animais , Humanos , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Regulação da Expressão Gênica , SoftwareRESUMO
Chromatin modifiers and transcriptional cofactors (collectively referred to as CFs) work with DNA-binding transcription factors (TFs) to regulate gene expression. In multicellular eukaryotes, distinct tissues each execute their own gene expression program for accurate differentiation and subsequent functionality. While the function of TFs in differential gene expression has been studied in detail in many systems, the contribution of CFs has remained less explored. Here we uncovered the contributions of CFs to gene regulation in the Caenorhabditis elegans intestine. We first annotated 366 CFs encoded by the C. elegans genome and assembled a library of 335 RNAi clones. Using this library, we analyzed the effects of individually depleting these CFs on the expression of 19 fluorescent transcriptional reporters in the intestine and identified 216 regulatory interactions. We found that different CFs interact specifically with different promoters, and that both essential and intestinally expressed CFs exhibit the highest proportion of interactions. We did not find all members of CF complexes acting on the same set of reporters but instead found diversity in the promoter targets of each complex component. Finally, we found that previously identified activation mechanisms for the acdh-1 promoter use different CFs and TFs. Overall, we demonstrate that CFs function specifically rather than ubiquitously at intestinal promoters and provide an RNAi resource for reverse genetic screens.
RESUMO
In our group, we aim to understand metabolism in the nematode Caenorhabditis elegans and its relationships with gene expression, physiology, and the response to therapeutic drugs. Visualization of the metabolic pathways that comprise the metabolic network is extremely useful for interpreting a wide variety of experiments. Detailed annotated metabolic pathway maps for C. elegans are mostly limited to pan-organismal maps, many with incomplete or inaccurate pathway and enzyme annotations. Here, we present WormPaths, which is composed of two parts: (1) the careful manual annotation of metabolic genes into pathways, categories, and levels, and (2) 62 pathway maps that include metabolites, metabolite structures, genes, reactions, and pathway connections between maps. These maps are available on the WormFlux website. We show that WormPaths provides easy-to-navigate maps and that the different levels in WormPaths can be used for metabolic pathway enrichment analysis of transcriptomic data. In the future, we envision further developing these maps to be more interactive, analogous to road maps that are available on mobile devices.
Assuntos
Caenorhabditis elegans , AnimaisRESUMO
BACKGROUND: Neurotrophic tyrosine receptor kinase (NTRK) gene fusions are oncogenic drivers in various tumor types. While NTRK gene fusions are predictive of benefit from tropomyosin receptor kinase inhibitors regardless of tumor type, the prognostic significance of NTRK gene fusions in a pan-tumor setting remains unclear. OBJECTIVE: This study evaluated the characteristics and prognosis of tropomyosin receptor kinase fusion cancer in the real-world setting. PATIENTS AND METHODS: This retrospective study used a de-identified clinico-genomic database and included patients with cancer who had comprehensive genomic profiling between January 2011 and July 2018. Patients were classified as having cancer with NTRK gene fusions or NTRK wild-type genes. Patients were matched with a 1:4 ratio (NTRK fusion:NTRK wild-type) using the Mahalanobis distance method on demographic and clinical characteristics, including age and Eastern Cooperative Oncology Group performance status. Descriptive analysis of clinical and molecular characteristics was conducted. Kaplan-Meier estimator and Cox regression were used for overall survival analysis. RESULTS: Median overall survival was 12.5 months (95% confidence interval 9.5-not estimable) and 16.5 months (95% confidence interval 12.5-22.5) in the NTRK gene fusion (n = 27) and NTRK wild-type cohorts (n = 107), respectively (hazard ratio 1.44; 95% confidence interval 0.61-3.37; p = 0.648). Co-occurrence of select targetable biomarkers including ALK, BRAF, ERBB2, EGFR, ROS1, and KRAS was lower in cancers with NTRK gene fusions than in NTRK wild-type cancers. CONCLUSIONS: Although the hazard ratio for overall survival suggested a higher risk of death for patients with NTRK gene fusions, the difference was not statistically significant. Co-occurrence of NTRK gene fusions and other actionable biomarkers was uncommon.
Assuntos
Neoplasias/genética , Proteínas de Fusão Oncogênica/genética , Oncogenes/genética , Receptores Proteína Tirosina Quinases/genética , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/mortalidade , Prognóstico , Análise de SobrevidaRESUMO
Neurotrophic tyrosine receptor kinase (NTRK) gene fusions lead to chimeric tropomyosin receptor kinase (TRK) fusion proteins, which act as primary oncogenic drivers in diverse tumor types in adults and children. Larotrectinib, a highly selective and central nervous system-active TRK inhibitor, has shown high objective response rates, durable disease control, and a favorable safety profile in patients with TRK fusion cancer. The impact of larotrectinib on health-related quality of life (HRQoL) was evaluated in adult and pediatric patients in two phase I/II clinical trials (NAVIGATE; NCT02576431 and SCOUT; NCT02637687). Patients completed HRQoL questionnaires (EORTC QLQ-C30, EQ-5D-5L, and PedsQL) at baseline and at planned treatment cycle visits. Changes in questionnaire scores were evaluated over time, and by tumor type and treatment response. Questionnaires from 40 adult and 17 pediatric (2-19 years of age) patients receiving larotrectinib were completed at baseline and at least one post-baseline timepoint. Meaningful within-patient HRQoL improvements occurred at one or more timepoints in 60% of adults and 76% of pediatric patients. Sustained improvements in EORTC QLQ-C30 and PedsQL scores were rapid, occurring within 2 months of treatment initiation in 68% and 71% of patients, respectively. Improvements were observed regardless of tumor type and appeared to correlate with clinical efficacy. The rapid within-patient HRQoL improvements in adult and pediatric patients with TRK fusion cancer are consistent with the clinical profile of larotrectinib. Our results provide valuable information for use of this agent in this patient population. A plain language summary of this article is available in the supplementary appendix.
Assuntos
Neoplasias/tratamento farmacológico , Neoplasias/psicologia , Pirazóis/farmacologia , Pirimidinas/farmacologia , Qualidade de Vida/psicologia , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Neoplasias/genética , Inibidores de Proteínas Quinases , Proteínas Quinases/genética , Receptor trkA/genética , Inquéritos e Questionários , Resultado do Tratamento , Tropomiosina/genética , Adulto JovemRESUMO
Randomized controlled basket trials investigating drugs targeting a rare molecular alteration are challenging. Using patients as their own control overcomes some of these challenges. Growth modulation index (GMI) is the ratio of progression-free survival (PFS) on the current therapy to time to progression (TTP) on the last prior line of therapy; GMI ≥ 1.33 is considered a threshold of meaningful clinical activity. In a retrospective, exploratory analysis among patients with advanced tropomyosin receptor kinase (TRK) fusion cancer treated with the selective TRK inhibitor larotrectinib who received ≥1 prior line of therapy for locally advanced/metastatic disease, we determined the proportion of patients with GMI ≥ 1.33; patients who had not progressed by data cut-off were censored for PFS. Among 72 eligible patients, median GMI was 2.68 (range 0.01-48.75). Forty-seven patients (65%) had GMI ≥ 1.33; 13/25 patients (52%) with GMI < 1.33 had not yet progressed on larotrectinib. Kaplan-Meier estimates showed a median GMI of 6.46. The probability of attaining GMI ≥ 1.33 was 0.75 (95% confidence interval (CI), 0.65-0.85). Median TTP on previous treatment was 3.0 months (95% CI, 2.6-4.4). Median PFS on larotrectinib was not estimable ((NE); 95% CI, NE; hazard ratio, 0.220 (95% CI, 0.146-0.332)). This analysis suggests larotrectinib improves PFS for patients with TRK fusion cancer compared with prior therapy.
RESUMO
Metabolism is a highly compartmentalized process that provides building blocks for biomass generation during development, homeostasis, and wound healing, and energy to support cellular and organismal processes. In metazoans, different cells and tissues specialize in different aspects of metabolism. However, studying the compartmentalization of metabolism in different cell types in a whole animal and for a particular stage of life is difficult. Here, we present MEtabolic models Reconciled with Gene Expression (MERGE), a computational pipeline that we used to predict tissue-relevant metabolic function at the network, pathway, reaction, and metabolite levels based on single-cell RNA-sequencing (scRNA-seq) data from the nematode Caenorhabditis elegans. Our analysis recapitulated known tissue functions in C. elegans, captured metabolic properties that are shared with similar tissues in human, and provided predictions for novel metabolic functions. MERGE is versatile and applicable to other systems. We envision this work as a starting point for the development of metabolic network models for individual cells as scRNA-seq continues to provide higher-resolution gene expression data.
Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/metabolismo , Regulação da Expressão Gênica/genética , Transcriptoma/genética , Algoritmos , Animais , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Biologia Computacional , Simulação por Computador , Redes Reguladoras de Genes , Gônadas/metabolismo , Mucosa Intestinal/metabolismo , Redes e Vias Metabólicas , Neuroglia/metabolismo , Especificidade de Órgãos/genética , Especificidade de Órgãos/fisiologia , RNA-Seq , Análise de Célula Única , Tela Subcutânea/metabolismoRESUMO
BACKGROUND: The selective TRK inhibitor larotrectinib was approved for paediatric and adult patients with advanced TRK fusion-positive solid tumours based on a primary analysis set of 55 patients. The aim of our analysis was to explore the efficacy and long-term safety of larotrectinib in a larger population of patients with TRK fusion-positive solid tumours. METHODS: Patients were enrolled and treated in a phase 1 adult, a phase 1/2 paediatric, or a phase 2 adolescent and adult trial. Some eligibility criteria differed between these studies. For this pooled analysis, eligible patients were aged 1 month or older, with a locally advanced or metastatic non-CNS primary, TRK fusion-positive solid tumour, who had received standard therapy previously if available. This analysis set includes the 55 patients on which approval of larotrectinib was based. Larotrectinib was administered orally (capsule or liquid formulation), on a continuous 28-day schedule, to adults mostly at a dose of 100 mg twice daily, and to paediatric patients mostly at a dose of 100 mg/m2 (maximum of 100 mg) twice daily. The primary endpoint was objective response as assessed by local investigators in an intention-to-treat analysis. Contributing trials are registered with ClinicalTrials.gov, NCT02122913 (active not recruiting), NCT02637687 (recruiting), and NCT02576431 (recruiting). FINDINGS: Between May 1, 2014, and Feb 19, 2019, 159 patients with TRK fusion-positive cancer were enrolled and treated with larotrectinib. Ages ranged from less than 1 month to 84 years. The proportion of patients with an objective response according to investigator assessment was 121 (79%, 95% CI 72-85) of 153 evaluable patients, with 24 (16%) having complete responses. In a safety population of 260 patients treated regardless of TRK fusion status, the most common grade 3 or 4 larotrectinib-related adverse events were increased alanine aminotransferase (eight [3%] of 260 patients), anaemia (six, 2%), and decreased neutrophil count (five [2%]). The most common larotrectinib-related serious adverse events were increased alanine aminotransferase (two [<1%] of 260 patients), increased aspartate aminotransferase (two [<1%]), and nausea (two [<1%]). No treatment-related deaths occurred. INTERPRETATION: These data confirm that TRK fusions define a unique molecular subgroup of advanced solid tumours for which larotrectinib is highly active. Safety data indicate that long-term administration of larotrectinib is feasible. FUNDING: Bayer and Loxo Oncology.
Assuntos
Neoplasias/química , Neoplasias/tratamento farmacológico , Proteínas/análise , Pirazóis/uso terapêutico , Pirimidinas/uso terapêutico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
In our group, we aim to understand metabolism in the nematode Caenorhabditis elegans and its relationships with gene expression, physiology and the response to therapeutic drugs. On March 15, 2020, a stay-at-home order was put into effect in the state of Massachusetts, USA, to flatten the curve of the spread of the novel SARS-CoV2 virus that causes COVID-19. For biomedical researchers in our state, this meant putting a hold on experiments for nine weeks until May 18, 2020. To keep the lab engaged and productive, and to enhance communication and collaboration, we embarked on an in-lab project that we all found important but that we never had the time for: the detailed annotation and drawing of C. elegans metabolic pathways. As a result, we present WormPaths, which is composed of two parts: 1) the careful manual annotation of metabolic genes into pathways, categories and levels, and 2) 66 pathway maps that include metabolites, metabolite structures, genes, reactions, and pathway connections between maps. These maps are available on our WormFlux website. We show that WormPaths provides easy-to-navigate maps and that the different levels in WormPaths can be used for metabolic pathway enrichment analysis of transcriptomic data. In the unfortunate event of additional lockdowns, we envision further developing these maps to be more interactive, with an analogy of road maps that are available on mobile devices.
RESUMO
Non-invasive skin-tightening devices can induce thermal denaturation and skin shrinkage via externally applied radiofrequency emissions or high-frequency ultrasound. Therefore, the purpose of this study is to develop and test a method for measurement of skin reduction associated with application of such energy devices. Twenty-five healthy participants with mild to moderate skin laxity of the arms were enrolled. Pinpoint microtattoos were placed at each of the treatment sites to delineate two 6 × 12 cm rectangles per subject. A non-stretchable filament, tape and marking pen apparatus was used to measure the size of each rectangle before treatment and at follow-up visit by two blinded investigators. After randomization, one side received a single pass with a radiofrequency device (6.78 MHz), while the contralateral side received multiple passes. Participants underwent two treatment sessions to each side 2 weeks apart, and returned for follow-up 4 weeks after the second treatment. Length and area measurement were analyzed to assess precision and accuracy of measurements and to compare efficacy of treatment between pre- and post-treatment. Concordance correlation coefficients (CCC) demonstrated substantial inter-investigator reliability and precision in length measurements (CCC, 0.94 to 0.98 in pre-treatment; 0.95 to 0.98 in post-treatment). Measurements at the 6-week post-treatment follow-up demonstrated a statistically significant skin reduction in all six of the measured parameters. A simple skin measurement method requiring minimal instrumentation can quantitatively evaluate skin shrinkage associated with non-invasive skin-tightening devices.
Assuntos
Envelhecimento da Pele/patologia , Pele/patologia , Tatuagem , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Ondas de Rádio , Reprodutibilidade dos Testes , Resultado do TratamentoRESUMO
INTRODUCTION: In a retrospective analysis of the SQUamous NSCLC treatment with the Inhibitor of EGF REceptor (SQUIRE) study, we investigated the efficacy and safety of single-agent necitumumab continuation therapy in patients with stage IV squamous non-small-cell lung cancer and in a subpopulation of patients with epidermal growth factor receptor (EGFR)-expressing tumors. PATIENTS AND METHODS: Patients were randomized 1:1 for ≤ 6 cycles of gemcitabine and cisplatin either with or without necitumumab. Patients who received necitumumab continued receiving single-agent necitumumab until progressive disease (necitumumab continuation). Tissue collection was mandatory in SQUIRE. EGFR protein expression was assessed using immunohistochemistry in a central lab. In this subgroup analysis we compared patients treated with necitumumab monotherapy after completion of ≥ 4 cycles of chemotherapy with those in the chemotherapy arm who were progression-free and did not discontinue because of adverse events (AEs) after completion of ≥ 4 cycles of chemotherapy (gemcitabine-cisplatin nonprogressors). The same analysis was done for the subgroup of EGFR-expressing patients (EGFR > 0). RESULTS: Baseline characteristics and chemotherapy exposure were well balanced between the necitumumab continuation (n = 261) and gemcitabine-cisplatin nonprogressor (n = 215) arms and in the EGFR-expressing population. Median overall survival (OS) from randomization in the necitumumab with gemcitabine-cisplatin versus gemcitabine-cisplatin nonprogressor arm was 15.9 versus 15.0 months (hazard ratio [HR], 0.85; 95% confidence interval [CI], 0.69-1.05) and median progression-free survival (PFS) from randomization was 7.4 versus 6.9 months (HR, 0.86; 95% CI, 0.70-1.06). OS and PFS benefits were similar when assessed from the postinduction period and in EGFR-expressing patients. No new safety findings emerged. CONCLUSION: There was a consistent treatment effect in favor of necitumumab continuation versus that in gemcitabine-cisplatin nonprogressors, with no unexpected increases in AEs in intention-to-treat as well as EGFR-expressing populations.
Assuntos
Anticorpos Monoclonais/uso terapêutico , Carcinoma de Células Escamosas/tratamento farmacológico , Imunoterapia/métodos , Neoplasias Pulmonares/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Escamosas/mortalidade , Cisplatino/uso terapêutico , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapêutico , Receptores ErbB/imunologia , Feminino , Humanos , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Análise de Sobrevida , GencitabinaRESUMO
Riboswitches are structured RNA motifs that control gene expression by sensing the concentrations of specific metabolites and make up a promising new class of antibiotic targets. S-Adenosylmethionine (SAM)-III riboswitch, mainly found in lactic acid bacteria, is involved in regulating methionine and SAM biosynthetic pathways. SAM-III riboswitch regulates the gene expression by switching the translation process on and off with respect to the absence and presence of the SAM ligand, respectively. In this study, an attempt is made to understand the key conformational transitions involved in ligand binding using atomistic molecular dynamics (MD) simulations performed in an explicit solvent environment. G26 is found to recognize the SAM ligand by forming hydrogen bonds, whereas the absence of the ligand leads to opening of the binding pocket. Consistent with experimental results, the absence of the SAM ligand weakens the base pairing interactions between the nucleobases that are part of the Shine-Dalgarno (SD) and anti-Shine-Dalgarno (aSD) sequences, which in turn facilitates recognition of the SD sequence by ribosomes. Detailed analysis reveals that a duplex-like structure formed by nucleotides from different parts of the RNA and the adenine base of the ligand is crucial for the stability of the completely folded state in the presence of the ligand. Previous experimental studies have shown that the SAM-III riboswitch exists in equilibrium between the unfolded and partially folded states in the absence of the ligand, which completely folds upon binding of the ligand. Comparison of the results presented here to the available experimental data indicates the structures obtained using the MD simulations resemble the partially folded state. Thus, this study provides a detailed understanding of the fully and partially folded structures of the SAM-III riboswitch in the presence and absence of the ligand, respectively. This study hypothesizes a dual role for the SAM ligand, which facilitates conformational switching between partially and fully folded states by forming a stable duplex-like structure and strengthening the interactions between SD and aSD nucleotides.