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1.
Genes Dev ; 31(13): 1339-1353, 2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28790158

RESUMO

Lung adenocarcinoma accounts for ∼40% of lung cancers, the leading cause of cancer-related death worldwide, and current therapies provide only limited survival benefit. Approximately half of lung adenocarcinomas harbor mutations in TP53 (p53), making these mutants appealing targets for lung cancer therapy. As mutant p53 remains untargetable, mutant p53-dependent phenotypes represent alternative targeting opportunities, but the prevalence and therapeutic relevance of such effects (gain of function and dominant-negative activity) in lung adenocarcinoma are unclear. Through transcriptional and functional analysis of murine KrasG12D -p53null , -p53R172H (conformational), and -p53R270H (contact) mutant lung tumors, we identified genotype-independent and genotype-dependent therapeutic sensitivities. Unexpectedly, we found that wild-type p53 exerts a dominant tumor-suppressive effect on mutant tumors, as all genotypes were similarly sensitive to its restoration in vivo. These data show that the potential of p53 targeted therapies is comparable across all p53-deficient genotypes and may explain the high incidence of p53 loss of heterozygosity in mutant tumors. In contrast, mutant p53 gain of function and their associated vulnerabilities can vary according to mutation type. Notably, we identified a p53R270H -specific sensitivity to simvastatin in lung tumors, and the transcriptional signature that underlies this sensitivity was also present in human lung tumors, indicating that this therapeutic approach may be clinically relevant.


Assuntos
Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/genética , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Sinvastatina/uso terapêutico , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Adenocarcinoma de Pulmão , Animais , Antineoplásicos/farmacologia , Pontos de Checagem do Ciclo Celular/genética , Morte Celular/genética , Linhagem Celular Tumoral , Modelos Animais de Doenças , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/genética , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Genótipo , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Imidazóis/farmacologia , Camundongos , Terapia de Alvo Molecular , Mutação , Piperazinas/farmacologia , Sinvastatina/farmacologia
2.
Ann Surg ; 277(4): e907-e913, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36892516

RESUMO

OBJECTIVE: To investigate the association between higher injury severity and increased informal caregiving received by injured older adults. SUMMARY OF BACKGROUND DATA: Injured older adults experience high rates of functional decline and disability after hospitalization. Little is known about the scope of caregiving received post-discharge, particularly from informal caregivers such as family. METHODS: We used the National Health and Aging Trends Study 2011 to 2018 linked to Medicare claims to identify adults ≥65 with hospital admission for traumatic injury and a National Health and Aging Trends Study interview within 12 months pre- and post-trauma. Injury severity was assessed using the injury severity score (ISS, low 0-9; moderate 10-15; severe 16-75). Patients reported the types and hours of formal and informal help received and any unmet care needs. Multi variable logistic regression models examined the association between ISS and increase in informal caregiving hours after discharge. RESULTS: We identified 430 trauma patients. Most were female (67.7%), non-Hispanic White (83.4%) and half were frail. The most common mechanism of injury was fall (80.8%) and median injury severity was low (ISS = 9). Those reporting receiving help with any activity increased post-trauma (49.0% to 72.4%, P < 0.01), and unmet needs nearly doubled (22.8% to 43.0%, P < 0.01). Patients had a median of 2 caregivers and most (75.6%) were informal, often family members. Median weekly hours of care received pre- versus post-injury increased from 8 to 14 (P < 0.01). ISS did not independently predict increase in caregiving hours; pre-trauma frailty predicted an increase in hours ≥8 per week. CONCLUSIONS: Injured older adults reported high baseline care needs which increased significantly after hospital discharge and were mostly met by informal caregivers. Injury was associated with increased need for assistance and unmet needs regardless of injury severity. These results can help set expectations for caregivers and facilitate post-acute care transitions.


Assuntos
Assistência ao Convalescente , Cuidadores , Humanos , Feminino , Idoso , Estados Unidos , Masculino , Medicare , Alta do Paciente , Família
3.
Microb Ecol ; 85(2): 747-764, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35129649

RESUMO

The epidermis of Chondrichthyan fishes consists of dermal denticles with production of minimal but protein-rich mucus that collectively, influence the attachment and biofilm development of microbes, facilitating a unique epidermal microbiome. Here, we use metagenomics to provide the taxonomic and functional characterization of the epidermal microbiome of the Triakis semifasciata (leopard shark) at three time-points collected across 4 years to identify links between microbial groups and host metabolism. Our aims include (1) describing the variation of microbiome taxa over time and identifying recurrent microbiome members (present across all time-points); (2) investigating the relationship between the recurrent and flexible taxa (those which are not found consistently across time-points); (3) describing the functional compositions of the microbiome which may suggest links with the host metabolism; and (4) identifying whether metabolic processes are shared across microbial genera or are unique to specific taxa. Microbial members of the microbiome showed high similarity between all individuals (Bray-Curtis similarity index = 82.7, where 0 = no overlap, 100 = total overlap) with the relative abundance of those members varying across sampling time-points, suggesting flexibility of taxa in the microbiome. One hundred and eighty-eight genera were identified as recurrent, including Pseudomonas, Erythrobacter, Alcanivorax, Marinobacter, and Sphingopxis being consistently abundant across time-points, while Limnobacter and Xyella exhibited switching patterns with high relative abundance in 2013, Sphingobium and Sphingomona in 2015, and Altermonas, Leeuwenhoekiella, Gramella, and Maribacter in 2017. Of the 188 genera identified as recurrent, the top 19 relatively abundant genera formed three recurrent groups. The microbiome also displayed high functional similarity between individuals (Bray-Curtis similarity index = 97.6) with gene function composition remaining consistent across all time-points. These results show that while the presence of microbial genera exhibits consistency across time-points, their abundances do fluctuate. Microbial functions however remain stable across time-points; thus, we suggest the leopard shark microbiomes exhibit functional redundancy. We show coexistence of microbes hosted in elasmobranch microbiomes that encode genes involved in utilizing nitrogen, but not fixing nitrogen, degrading urea, and resistant to heavy metal.


Assuntos
Microbiota , Tubarões , Animais , Epiderme
4.
Proc Natl Acad Sci U S A ; 117(30): 17808-17819, 2020 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-32661168

RESUMO

p53 is the most frequently mutated, well-studied tumor-suppressor gene, yet the molecular basis of the switch from p53-induced cell-cycle arrest to apoptosis remains poorly understood. Using a combination of transcriptomics and functional genomics, we unexpectedly identified a nodal role for the caspase-8 paralog and only human pseudo-caspase, FLIP(L), in regulating this switch. Moreover, we identify FLIP(L) as a direct p53 transcriptional target gene that is rapidly up-regulated in response to Nutlin-3A, an MDM2 inhibitor that potently activates p53. Genetically or pharmacologically inhibiting expression of FLIP(L) using siRNA or entinostat (a clinically relevant class-I HDAC inhibitor) efficiently promoted apoptosis in colorectal cancer cells in response to Nutlin-3A, which otherwise predominantly induced cell-cycle arrest. Enhanced apoptosis was also observed when entinostat was combined with clinically relevant, p53-activating chemotherapy in vitro, and this translated into enhanced in vivo efficacy. Mechanistically, FLIP(L) inhibited p53-induced apoptosis by blocking activation of caspase-8 by the TRAIL-R2/DR5 death receptor; notably, this activation was not dependent on receptor engagement by its ligand, TRAIL. In the absence of caspase-8, another of its paralogs, caspase-10 (also transcriptionally up-regulated by p53), induced apoptosis in Nutlin-3A-treated, FLIP(L)-depleted cells, albeit to a lesser extent than in caspase-8-proficient cells. FLIP(L) depletion also modulated transcription of canonical p53 target genes, suppressing p53-induced expression of the cell-cycle regulator p21 and enhancing p53-induced up-regulation of proapoptotic PUMA. Thus, even in the absence of caspase-8/10, FLIP(L) silencing promoted p53-induced apoptosis by enhancing PUMA expression. Thus, we report unexpected, therapeutically relevant roles for FLIP(L) in determining cell fate following p53 activation.


Assuntos
Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Acetilação , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/genética , Benzamidas/farmacologia , Caspase 8/metabolismo , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Linhagem Celular Tumoral , Sinergismo Farmacológico , Regulação da Expressão Gênica , Humanos , Imidazóis/metabolismo , Modelos Biológicos , Piperazinas/metabolismo , Ligação Proteica , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Piridinas/farmacologia , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Proteína Supressora de Tumor p53/genética
5.
Gut ; 71(12): 2502-2517, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35477539

RESUMO

OBJECTIVE: Stroma-rich tumours represent a poor prognostic subtype in stage II/III colon cancer (CC), with high relapse rates and limited response to standard adjuvant chemotherapy. DESIGN: To address the lack of efficacious therapeutic options for patients with stroma-rich CC, we stratified our human tumour cohorts according to stromal content, enabling identification of the biology underpinning relapse and potential therapeutic vulnerabilities specifically within stroma-rich tumours that could be exploited clinically. Following human tumour-based discovery and independent clinical validation, we use a series of in vitro and stroma-rich in vivo models to test and validate the therapeutic potential of elevating the biology associated with reduced relapse in human tumours. RESULTS: By performing our analyses specifically within the stroma-rich/high-fibroblast (HiFi) subtype of CC, we identify and validate the clinical value of a HiFi-specific prognostic signature (HPS), which stratifies tumours based on STAT1-related signalling (High-HPS v Low-HPS=HR 0.093, CI 0.019 to 0.466). Using in silico, in vitro and in vivo models, we demonstrate that the HPS is associated with antigen processing and presentation within discrete immune lineages in stroma-rich CC, downstream of double-stranded RNA and viral response signalling. Treatment with the TLR3 agonist poly(I:C) elevated the HPS signalling and antigen processing phenotype across in vitro and in vivo models. In an in vivo model of stroma-rich CC, poly(I:C) treatment significantly increased systemic cytotoxic T cell activity (p<0.05) and reduced liver metastases (p<0.0002). CONCLUSION: This study reveals new biological insight that offers a novel therapeutic option to reduce relapse rates in patients with the worst prognosis CC.


Assuntos
Biomarcadores Tumorais , Neoplasias do Colo , Humanos , Biomarcadores Tumorais/genética , Células Estromais/patologia , Recidiva Local de Neoplasia/prevenção & controle , Recidiva Local de Neoplasia/patologia , Neoplasias do Colo/patologia , Prognóstico
6.
Nature ; 531(7592): 110-3, 2016 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-26909577

RESUMO

The RAS/MAPK (mitogen-activated protein kinase) signalling pathway is frequently deregulated in non-small-cell lung cancer, often through KRAS activating mutations. A single endogenous mutant Kras allele is sufficient to promote lung tumour formation in mice but malignant progression requires additional genetic alterations. We recently showed that advanced lung tumours from Kras(G12D/+);p53-null mice frequently exhibit Kras(G12D) allelic enrichment (Kras(G12D)/Kras(wild-type) > 1) (ref. 7), implying that mutant Kras copy gains are positively selected during progression. Here we show, through a comprehensive analysis of mutant Kras homozygous and heterozygous mouse embryonic fibroblasts and lung cancer cells, that these genotypes are phenotypically distinct. In particular, Kras(G12D/G12D) cells exhibit a glycolytic switch coupled to increased channelling of glucose-derived metabolites into the tricarboxylic acid cycle and glutathione biosynthesis, resulting in enhanced glutathione-mediated detoxification. This metabolic rewiring is recapitulated in mutant KRAS homozygous non-small-cell lung cancer cells and in vivo, in spontaneous advanced murine lung tumours (which display a high frequency of Kras(G12D) copy gain), but not in the corresponding early tumours (Kras(G12D) heterozygous). Finally, we demonstrate that mutant Kras copy gain creates unique metabolic dependences that can be exploited to selectively target these aggressive mutant Kras tumours. Our data demonstrate that mutant Kras lung tumours are not a single disease but rather a heterogeneous group comprising two classes of tumours with distinct metabolic profiles, prognosis and therapeutic susceptibility, which can be discriminated on the basis of their relative mutant allelic content. We also provide the first, to our knowledge, in vivo evidence of metabolic rewiring during lung cancer malignant progression.


Assuntos
Variações do Número de Cópias de DNA/genética , Genes ras/genética , Glucose/metabolismo , Glicólise , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Mutação/genética , Alelos , Animais , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Transformação Celular Neoplásica/efeitos dos fármacos , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Ciclo do Ácido Cítrico , Progressão da Doença , Feminino , Fibroblastos/metabolismo , Genótipo , Glutationa/biossíntese , Glutationa/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Oxirredução , Fenótipo , Prognóstico
7.
Gerodontology ; 39(3): 257-265, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34105187

RESUMO

OBJECTIVE: Many older patients, housebound or living in long-term care facilities (LTCFs) have limited access to dental care. This descriptive qualitative study aimed to understand general dental practitioners (GDPs) attitudes and perceived barriers to undertaking Domiciliary Dental Care (DDC) for those patients in Northern Ireland (NI). METHODS: Semi-structured telephone interviews were conducted with a purposive sample of 12 GDPs in Northern Ireland. Interviews were digitally recorded and transcribed verbatim. An iterative coding process using theme-analytic methods was used. RESULTS: The data were characterised into four major themes-risk of professional litigation, remuneration for those undertaking DDC, complexity of treatment, and the overall framework of the dental care system in NI. Two minor themes identified were practice culture and reasons for undertaking DDC. The GDPs in the study identified a number of barriers to undertaking DDC including a legal requirement to transport oxygen, lack of organisation and limited oral hygiene care provision in LTCFs, and confusion around their responsibilities for provision of DDC. Those GDPs who were providing DDC indicated that they did so out of kindness and a sense of loyalty to their long-standing patients. CONCLUSION: The GDPs in this study identified a number of significant barriers to provision of DDC at organisational, structural and clinical levels. The GDPs indicated that they required clarification of their responsibilities around DDC with clear guidelines necessary given the increase in demand for this service.


Assuntos
Odontólogos , Odontologia Geral , Idoso , Atitude do Pessoal de Saúde , Assistência Odontológica , Humanos , Assistência de Longa Duração , Irlanda do Norte , Oxigênio , Papel Profissional
8.
J Pain Symptom Manage ; 68(3): 205-213.e6, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38782305

RESUMO

CONTEXT: The COVID-19 pandemic disproportionately impacted non-Hispanic Black and Hispanic patients. However, little is known about the quality of serious illness communication in these communities during this time. OBJECTIVE: We aimed to determine whether racial and ethnic disparities manifested in serious illness conversations during the pandemic. METHODS: This was a retrospective, observational, cohort study of adult patients with a documented serious illness conversation from March 2020 to April 2021. Serious illness conversation documentation quality was assessed by counting the median number (IQR) of conversation domains and their elements included in the documentation. Domains included (1) values and goals, (2) prognosis and illness understanding, (3) end-of-life care planning, and (4) life-sustaining treatment preferences. A multivariable ordinal logistic regression analysis was conducted to assess associations between differences in serious illness documentation quality with patient race and ethnicity. RESULTS: Among 291 patients, 149 (51.2%) were non-Hispanic White; 81 (27.8%) were non-Hispanic Black; and 61 (21.0%) were Hispanic patients. Non-Hispanic Black patients were associated with fewer domains (OR 0.46 [95% CI 0.25, 0.84]; P=.01) included in their serious illness conversation documentation compared to non-Hispanic White patients. Both non-Hispanic Black (OR 0.35 [95% CI 0.20, 0.62]; P<.001) and Hispanic patients (OR 0.29 [95% CI 0.14, 0.58]; P<.001) were associated with fewer elements in the values and goals domain compared to non-Hispanic White patients in their serious illness documentation. CONCLUSION: During the COVID-19 pandemic, serious illness conversation documentation among non-Hispanic Black and Hispanic patients was less comprehensive compared to non-Hispanic White patients.


Assuntos
COVID-19 , Doença Catastrófica , Comunicação , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Negro ou Afro-Americano , Estudos de Coortes , Etnicidade , Disparidades em Assistência à Saúde/etnologia , Hispânico ou Latino , Estudos Retrospectivos , Assistência Terminal , Brancos
9.
Nat Genet ; 56(3): 458-472, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38351382

RESUMO

Molecular stratification using gene-level transcriptional data has identified subtypes with distinctive genotypic and phenotypic traits, as exemplified by the consensus molecular subtypes (CMS) in colorectal cancer (CRC). Here, rather than gene-level data, we make use of gene ontology and biological activation state information for initial molecular class discovery. In doing so, we defined three pathway-derived subtypes (PDS) in CRC: PDS1 tumors, which are canonical/LGR5+ stem-rich, highly proliferative and display good prognosis; PDS2 tumors, which are regenerative/ANXA1+ stem-rich, with elevated stromal and immune tumor microenvironmental lineages; and PDS3 tumors, which represent a previously overlooked slow-cycling subset of tumors within CMS2 with reduced stem populations and increased differentiated lineages, particularly enterocytes and enteroendocrine cells, yet display the worst prognosis in locally advanced disease. These PDS3 phenotypic traits are evident across numerous bulk and single-cell datasets, and demark a series of subtle biological states that are currently under-represented in pre-clinical models and are not identified using existing subtyping classifiers.


Assuntos
Neoplasias Colorretais , Humanos , Neoplasias Colorretais/patologia , Prognóstico , Diferenciação Celular/genética , Fenótipo , Biomarcadores Tumorais/genética , Perfilação da Expressão Gênica
10.
JAMA Surg ; 158(9): 945-952, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37405733

RESUMO

Importance: Caregiver burden, characterized by psychological distress and physical morbidity, affects more than 50 million family caregivers of older adults in the United States. Risk factors for caregiver burden among caregivers of older trauma patients have not been well characterized. Objective: To characterize postdischarge caregiver burden among caregivers of older trauma patients and identify targets that can inform interventions to improve their experience. Design, Setting, and Participants: This study used a repeated cross-sectional design. Participants were family caregivers for adults 65 years or older with traumatic injury who were discharged from 1 of 2 level I trauma centers. Telephone interviews were conducted at 1 month and 3 months postdischarge with family caregivers (identified by the patient as family or friends who provided unpaid care). Admissions occurred between December 2019 and May 2021, and data were analyzed from June 2021 to May 2022. Exposure: Hospital admission for geriatric trauma. Main Outcome and Measures: High caregiver burden was defined by a score of 17 or higher on the 12-item Zarit Burden Interview. Caregiver self-efficacy and preparedness for caregiving were assessed via the Revised Scale for Caregiving Self-Efficacy and Preparedness for Caregiving Scale, respectively. Associations between caregiver self-efficacy, preparedness for caregiving, and caregiver burden were tested via mixed-effect logistic regression. Results: There were 154 family caregivers enrolled in the study. Their mean (SD) age was 60.6 (13.0) years (range, 18-92 years), 108 of 154 were female (70.6%). The proportion of caregivers experiencing high burden (Zarit Burden Interview score ≥17) was unchanged over time (1 month, 38 caregivers [30.9%]; 3 months, 37 caregivers [31.4%]). Participants with lower caregiver self-efficacy and preparedness for caregiving were more likely to experience greater caregiver burden (odds ratio [OR], 7.79; 95% CI, 2.54-23.82; P < .001; and OR, 5.76; 95% CI, 1.86-17.88; P = .003, respectively). Conclusion and Relevance: This study found that nearly a third of family caregivers of older trauma patients experience high caregiver burden up to 3 months after the patients' discharge. Targeted interventions to increase caregiver self-efficacy and preparedness may reduce caregiver burden in geriatric trauma.


Assuntos
Sobrecarga do Cuidador , Cuidadores , Humanos , Feminino , Estados Unidos , Idoso , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Masculino , Cuidadores/psicologia , Alta do Paciente , Estudos Transversais , Assistência ao Convalescente , Apoio Social
11.
Front Microbiol ; 14: 1031711, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36937279

RESUMO

Marine host-associated microbiomes are affected by a combination of species-specific (e.g., host ancestry, genotype) and habitat-specific features (e.g., environmental physiochemistry and microbial biogeography). The stingray epidermis provides a gradient of characteristics from high dermal denticles coverage with low mucus to reduce dermal denticles and high levels of mucus. Here we investigate the effects of host phylogeny and habitat by comparing the epidermal microbiomes of Myliobatis californica (bat rays) with a mucus rich epidermis, and Urobatis halleri (round rays) with a mucus reduced epidermis from two locations, Los Angeles and San Diego, California (a 150 km distance). We found that host microbiomes are species-specific and distinct from the water column, however composition of M. californica microbiomes showed more variability between individuals compared to U. halleri. The variability in the microbiome of M. californica caused the microbial taxa to be similar across locations, while U. halleri microbiomes were distinct across locations. Despite taxonomic differences, Shannon diversity is the same across the two locations in U. halleri microbiomes suggesting the taxonomic composition are locally adapted, but diversity is maintained by the host. Myliobatis californica and U. halleri microbiomes maintain functional similarity across Los Angeles and San Diego and each ray showed several unique functional genes. Myliobatis californica has a greater relative abundance of RNA Polymerase III-like genes in the microbiome than U. halleri, suggesting specific adaptations to a heavy mucus environment. Construction of Metagenome Assembled Genomes (MAGs) identified novel microbial species within Rhodobacteraceae, Moraxellaceae, Caulobacteraceae, Alcanivoracaceae and Gammaproteobacteria. All MAGs had a high abundance of active RNA processing genes, heavy metal, and antibiotic resistant genes, suggesting the stingray mucus supports high microbial growth rates, which may drive high levels of competition within the microbiomes increasing the antimicrobial properties of the microbes.

12.
Cell Rep ; 42(5): 112475, 2023 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-37167967

RESUMO

Immunosuppressive tumor microenvironments (TMEs) reduce the effectiveness of immune responses in cancer. Mesenchymal stromal cells (MSCs), precursors to cancer-associated fibroblasts (CAFs), promote tumor progression by enhancing immune cell suppression in colorectal cancer (CRC). Hyper-sialylation of glycans promotes immune evasion in cancer through binding of sialic acids to their receptors, Siglecs, expressed on immune cells, which results in inhibition of effector functions. The role of sialylation in shaping MSC/CAF immunosuppression in the TME is not well characterized. In this study, we show that tumor-conditioned stromal cells have increased sialyltransferase expression, α2,3/6-linked sialic acid, and Siglec ligands. Tumor-conditioned stromal cells and CAFs induce exhausted immunomodulatory CD8+ PD1+ and CD8+ Siglec-7+/Siglec-9+ T cell phenotypes. In vivo, targeting stromal cell sialylation reverses stromal cell-mediated immunosuppression, as shown by infiltration of CD25 and granzyme B-expressing CD8+ T cells in the tumor and draining lymph node. Targeting stromal cell sialylation may overcome immunosuppression in the CRC TME.


Assuntos
Fibroblastos Associados a Câncer , Neoplasias , Humanos , Linfócitos T CD8-Positivos , Microambiente Tumoral , Terapia de Imunossupressão , Células Estromais/metabolismo , Neoplasias/patologia , Fibroblastos Associados a Câncer/metabolismo , Lectinas Semelhantes a Imunoglobulina de Ligação ao Ácido Siálico/metabolismo
13.
Inflamm Res ; 61(7): 759-73, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22487851

RESUMO

OBJECTIVE AND DESIGN: A mathematical analysis of leukocytes accumulating in experimental autoimmune uveitis (EAU), using ordinary differential equations (ODEs) and incorporating a barrier to cell traffic. MATERIALS AND SUBJECTS: Data from an analysis of the kinetics of cell accumulation within the eye during EAU. METHODS: We applied a well-established mathematical approach that uses ODEs to describe the behaviour of cells on both sides of the blood-retinal barrier and compared data from the mathematical model with experimental data from animals with EAU. RESULTS: The presence of the barrier is critical to the ability of the model to qualitatively reproduce the experimental data. However, barrier breakdown is not sufficient to produce a surge of cells into the eye, which depends also on asymmetry in the rates at which cells can penetrate the barrier. Antigen-presenting cell (APC) generation also plays a critical role and we can derive from the model the ratio for APC production under inflammatory conditions relative to production in the resting state, which has a value that agrees closely with that found by experiment. CONCLUSIONS: Asymmetric trafficking and the dynamics of APC production play an important role in the dynamics of cell accumulation in EAU.


Assuntos
Doenças Autoimunes/imunologia , Barreira Hematorretiniana/imunologia , Leucócitos/imunologia , Modelos Biológicos , Uveíte/imunologia , Animais , Células Apresentadoras de Antígenos/imunologia , Camundongos
14.
Sci Signal ; 15(756): eabj3490, 2022 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-36256706

RESUMO

Mutations in guanosine triphosphatase KRAS are common in lung, colorectal, and pancreatic cancers. The constitutive activity of mutant KRAS and its downstream signaling pathways induces metabolic rewiring in tumor cells that can promote resistance to existing therapeutics. In this review, we discuss the metabolic pathways that are altered in response to treatment and those that can, in turn, alter treatment efficacy, as well as the role of metabolism in the tumor microenvironment (TME) in dictating the therapeutic response in KRAS-driven cancers. We highlight metabolic targets that may provide clinical opportunities to overcome therapeutic resistance and improve survival in patients with these aggressive cancers.


Assuntos
Neoplasias Pancreáticas , Proteínas Proto-Oncogênicas p21(ras) , Humanos , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Mutação , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Transdução de Sinais , Guanosina , Linhagem Celular Tumoral , Microambiente Tumoral/genética
15.
PLoS One ; 17(1): e0262027, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35045091

RESUMO

BACKGROUND: In recent years, interest has grown in whether and to what extent demographic diversity sparks discovery and innovation in research. At the same time, topic modeling has been employed to discover differences in what women and men write about. This study engages these two strands of scholarship to explore associations between changing researcher demographics and research questions asked in the discipline of history. Specifically, we analyze developments in history as women entered the field. METHODS: We focus on author gender in diachronic analysis of history dissertations from 1980 (when online data is first available) to 2015 and a select set of general history journals from 1950 to 2015. We use correlated topic modeling and network visualizations to map developments in research agendas over time and to examine how women and men have contributed to these developments. RESULTS: Our summary snapshot of aggregate interests of women and men for the period 1950 to 2015 identifies new topics associated with women authors: gender and women's history, body history, family and households, consumption and consumerism, and sexuality. Diachronic analysis demonstrates that while women pioneered topics such as gender and women's history or the history of sexuality, these topics broaden over time to become methodological frameworks that historians widely embraced and that changed in interesting ways as men engaged with them. Our analysis of history dissertations surface correlations between advisor/advisee gender pairings and choice of dissertation topic. CONCLUSIONS: Overall, this quantitative longitudinal study suggests that the growth in women historians has coincided with the broadening of research agendas and an increased sensitivity to new topics and methodologies in the field.


Assuntos
Sexualidade
16.
Viruses ; 14(9)2022 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-36146775

RESUMO

The epidermal microbiome is a critical element of marine organismal immunity, but the epidermal virome of marine organisms remains largely unexplored. The epidermis of sharks represents a unique viromic ecosystem. Sharks secrete a thin layer of mucus which harbors a diverse microbiome, while their hydrodynamic dermal denticles simultaneously repel environmental microbes. Here, we sampled the virome from the epidermis of three shark species in the family Carcharhinidae: the genetically and morphologically similar Carcharhinus obscurus (n = 6) and Carcharhinus galapagensis (n = 10) and the outgroup Galeocerdo cuvier (n = 15). Virome taxonomy was characterized using shotgun metagenomics and compared with a suite of multivariate analyses. All three sharks retain species-specific but highly similar epidermal viromes dominated by uncharacterized bacteriophages which vary slightly in proportional abundance within and among shark species. Intraspecific variation was lower among C. galapagensis than among C. obscurus and G. cuvier. Using both the annotated and unannotated reads, we were able to determine that the Carcharhinus galapagensis viromes were more similar to that of G. cuvier than they were to that of C. obscurus, suggesting that behavioral niche may be a more prominent driver of virome than host phylogeny.


Assuntos
Bacteriófagos , Mergulho , Tubarões , Viroma , Animais , Bacteriófagos/genética , Ecossistema , Epiderme , Metagenômica
17.
Microorganisms ; 10(10)2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36296361

RESUMO

Characterizations of shark-microbe systems in wild environments have outlined patterns of species-specific microbiomes; however, whether captivity affects these trends has yet to be determined. We used high-throughput shotgun sequencing to assess the epidermal microbiome belonging to leopard sharks (Triakis semifasciata) in captive (Birch Aquarium, La Jolla California born and held permanently in captivity), semi-captive (held in captivity for <1 year in duration and scheduled for release; Scripps Institute of Oceanography, San Diego, CA, USA) and wild environments (Moss Landing and La Jolla, CA, USA). Here, we report captive environments do not drive epidermal microbiome compositions of T. semifasciata to significantly diverge from wild counterparts as life-long captive sharks maintain a species-specific epidermal microbiome resembling those associated with semi-captive and wild populations. Major taxonomic composition shifts observed were inverse changes of top taxonomic contributors across captive duration, specifically an increase of Pseudoalteromonadaceae and consequent decrease of Pseudomonadaceae relative abundance as T. semifasciata increased duration in captive conditions. Moreover, we show captivity did not lead to significant losses in microbial α-diversity of shark epidermal communities. Finally, we present a novel association between T. semifasciata and the Muricauda genus as Metagenomes associated genomes revealed a consistent relationship across captive, semi-captive, and wild populations. Since changes in microbial communities is often associated with poor health outcomes, our report illustrates that epidermally associated microbes belonging to T. semifasciata are not suffering detrimental impacts from long or short-term captivity. Therefore, conservation programs which house sharks in aquariums are providing a healthy environment for the organisms on display. Our findings also expand on current understanding of shark epidermal microbiomes, explore the effects of ecologically different scenarios on benthic shark microbe associations, and highlight novel associations that are consistent across captive gradients.

18.
Nat Commun ; 13(1): 7551, 2022 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-36477656

RESUMO

The pro-tumourigenic role of epithelial TGFß signalling in colorectal cancer (CRC) is controversial. Here, we identify a cohort of born to be bad early-stage (T1) colorectal tumours, with aggressive features and a propensity to disseminate early, that are characterised by high epithelial cell-intrinsic TGFß signalling. In the presence of concurrent Apc and Kras mutations, activation of epithelial TGFß signalling rampantly accelerates tumourigenesis and share transcriptional signatures with those of the born to be bad T1 human tumours and predicts recurrence in stage II CRC. Mechanistically, epithelial TGFß signalling induces a growth-promoting EGFR-signalling module that synergises with mutant APC and KRAS to drive MAPK signalling that re-sensitise tumour cells to MEK and/or EGFR inhibitors. Together, we identify epithelial TGFß signalling both as a determinant of early dissemination and a potential therapeutic vulnerability of CRC's with born to be bad traits.


Assuntos
Apoptose , Fator de Crescimento Transformador beta , Humanos , Apoptose/genética
19.
JAMA Intern Med ; 182(6): 624-633, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35467698

RESUMO

Importance: The psychological symptoms associated with having a family member admitted to the intensive care unit (ICU) during the COVID-19 pandemic are not well defined. Objective: To examine the prevalence of symptoms of stress-related disorders, primarily posttraumatic stress disorder (PTSD), in family members of patients admitted to the ICU with COVID-19 approximately 90 days after admission. Design, Setting, and Participants: This prospective, multisite, mixed-methods observational cohort study assessed 330 family members of patients admitted to the ICU (except in New York City, which had a random sample of 25% of all admitted patients per month) between February 1 and July 31, 2020, at 8 academic-affiliated and 4 community-based hospitals in 5 US states. Exposure: Having a family member in the ICU with COVID-19. Main Outcomes and Measures: Symptoms of PTSD at 3 months, as defined by a score of 10 or higher on the Impact of Events Scale 6 (IES-6). Results: A total of 330 participants (mean [SD] age, 51.2 [15.1] years; 228 [69.1%] women; 150 [52.8%] White; 92 [29.8%] Hispanic) were surveyed at the 3-month time point. Most individuals were the patients' child (129 [40.6%]) or spouse or partner (81 [25.5%]). The mean (SD) IES-6 score at 3 months was 11.9 (6.1), with 201 of 316 respondents (63.6%) having scores of 10 or higher, indicating significant symptoms of PTSD. Female participants had an adjusted mean IES-6 score of 2.6 points higher (95% CI, 1.4-3.8; P < .001) than male participants, whereas Hispanic participants scored a mean of 2.7 points higher compared with non-Hispanic participants (95% CI, 1.0-4.3; P = .002). Those with graduate school experience had an adjusted mean score of 3.3 points lower (95% CI, 1.5-5.1; P < .001) compared with those with up to a high school degree or equivalent. Qualitative analyses found no substantive differences in the emotional or communication-related experiences between those with high vs low PTSD scores, but those with higher scores exhibited more distrust of practitioners. Conclusions and Relevance: In this cohort study, symptoms of PTSD among family members of ICU patients with COVID-19 were high. Hispanic ethnicity and female gender were associated with higher symptoms. Those with higher scores reported more distrust of practitioners.


Assuntos
COVID-19 , Transtornos de Estresse Pós-Traumáticos , COVID-19/epidemiologia , Criança , Estudos de Coortes , Família/psicologia , Feminino , Humanos , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Pandemias , Estudos Prospectivos , Transtornos de Estresse Pós-Traumáticos/psicologia
20.
Cancers (Basel) ; 13(13)2021 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-34283054

RESUMO

Drug resistance is a major cause of cancer treatment failure, effectively driven by processes that promote escape from therapy-induced cell death. The mechanisms driving evasion of apoptosis have been widely studied across multiple cancer types, and have facilitated new and exciting therapeutic discoveries with the potential to improve cancer patient care. However, an increasing understanding of the crosstalk between cancer hallmarks has highlighted the complexity of the mechanisms of drug resistance, co-opting pathways outside of the canonical "cell death" machinery to facilitate cell survival in the face of cytotoxic stress. Rewiring of cellular metabolism is vital to drive and support increased proliferative demands in cancer cells, and recent discoveries in the field of cancer metabolism have uncovered a novel role for these programs in facilitating drug resistance. As a key organelle in both metabolic and apoptotic homeostasis, the mitochondria are at the forefront of these mechanisms of resistance, coordinating crosstalk in the event of cellular stress, and promoting cellular survival. Importantly, the appreciation of this role metabolism plays in the cytotoxic response to therapy, and the ability to profile metabolic adaptions in response to treatment, has encouraged new avenues of investigation into the potential of exploiting metabolic addictions to improve therapeutic efficacy and overcome drug resistance in cancer. Here, we review the role cancer metabolism can play in mediating drug resistance, and the exciting opportunities presented by imposed metabolic vulnerabilities.

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