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1.
Alzheimers Dement (N Y) ; 8(1): e12225, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35128026

RESUMO

Gut-microbiome-inflammation interactions have been linked to neurodegeneration in Alzheimer's disease (AD) and other disorders. We hypothesized that treatment with rifaximin, a minimally absorbed gut-specific antibiotic, may modify the neurodegenerative process by changing gut flora and reducing neurotoxic microbial drivers of inflammation. In a pilot, open-label trial, we treated 10 subjects with mild to moderate probable AD dementia (Mini-Mental Status Examination (MMSE) = 17 ± 3) with rifaximin for 3 months. Treatment was associated with a significant reduction in serum neurofilament-light levels (P < .004) and a significant increase in fecal phylum Firmicutes microbiota. Serum phosphorylated tau (pTau)181 and glial fibrillary acidic protein (GFAP) levels were reduced (effect sizes of -0.41 and -0.48, respectively) but did not reach statistical significance. In addition, there was a nonsignificant downward trend in serum cytokine interleukin (IL)-6 and IL-13 levels. Cognition was unchanged. Increases in stool Erysipelatoclostridium were correlated significantly with reductions in serum pTau181 and serum GFAP. Insights from this pilot trial are being used to design a larger placebo-controlled clinical trial to determine if specific microbial flora/products underlie neurodegeneration, and whether rifaximin is clinically efficacious as a therapeutic.

2.
Am J Pathol ; 190(1): 93-107, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31669305

RESUMO

Fibrolamellar carcinoma (FLC) is characterized by in-frame fusion of DnaJ heat shock protein family (Hsp40) member B1 (DNAJB1) with protein kinase cAMP-activated catalytic subunit α (PRKACA) and by dense desmoplasia. Surgery is the only effective treatment because mechanisms supporting tumor survival are unknown. We used single-cell RNA sequencing to characterize a patient-derived FLC xenograft model and identify therapeutic targets. Human FLC cells segregated into four discrete clusters that all expressed the oncogene Yes-associated protein 1 (YAP1). The two communities most enriched with cells coexpressing FLC markers [CD68, A-kinase anchoring protein 12 (AKAP12), cytokeratin 7, epithelial cell adhesion molecule (EPCAM), and carbamoyl palmitate synthase-1] also had the most cells expressing YAP1 and its proproliferative target genes (AREG and CCND1), suggesting these were proliferative FLC cell clusters. The other two clusters were enriched with cells expressing profibrotic YAP1 target genes, ACTA2, ELN, and COL1A1, indicating these were fibrogenic FLC cells. All clusters expressed the YAP1 target gene and mesothelial progenitor marker mesothelin, and many mesothelin-positive cells coexpressed albumin. Trajectory analysis predicted that the four FLC communities were derived from a single cell type transitioning among phenotypic states. After establishing a novel FLC cell line that harbored the DNAJB1-PRKACA fusion, YAP1 was inhibited, which significantly reduced expression of known YAP1 target genes as well as cell growth and migration. Thus, both FLC epithelial and stromal cells appear to arise from DNAJB1-PRKACA fusion in a YAP1-dependent liver mesothelial progenitor, identifying YAP1 as a target for FLC therapy.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Carcinoma Hepatocelular/patologia , Epitélio/patologia , Neoplasias Hepáticas/patologia , Fígado/patologia , Análise de Célula Única/métodos , Células-Tronco/patologia , Fatores de Transcrição/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Biomarcadores Tumorais , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Epitélio/metabolismo , Regulação Neoplásica da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Fígado/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Mesotelina , Camundongos , Camundongos SCID , Células-Tronco/metabolismo , Fatores de Transcrição/genética , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto , Proteínas de Sinalização YAP
3.
Semin Cancer Biol ; 35 Suppl: S276-S304, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26590477

RESUMO

Targeted therapies and the consequent adoption of "personalized" oncology have achieved notable successes in some cancers; however, significant problems remain with this approach. Many targeted therapies are highly toxic, costs are extremely high, and most patients experience relapse after a few disease-free months. Relapses arise from genetic heterogeneity in tumors, which harbor therapy-resistant immortalized cells that have adopted alternate and compensatory pathways (i.e., pathways that are not reliant upon the same mechanisms as those which have been targeted). To address these limitations, an international task force of 180 scientists was assembled to explore the concept of a low-toxicity "broad-spectrum" therapeutic approach that could simultaneously target many key pathways and mechanisms. Using cancer hallmark phenotypes and the tumor microenvironment to account for the various aspects of relevant cancer biology, interdisciplinary teams reviewed each hallmark area and nominated a wide range of high-priority targets (74 in total) that could be modified to improve patient outcomes. For these targets, corresponding low-toxicity therapeutic approaches were then suggested, many of which were phytochemicals. Proposed actions on each target and all of the approaches were further reviewed for known effects on other hallmark areas and the tumor microenvironment. Potential contrary or procarcinogenic effects were found for 3.9% of the relationships between targets and hallmarks, and mixed evidence of complementary and contrary relationships was found for 7.1%. Approximately 67% of the relationships revealed potentially complementary effects, and the remainder had no known relationship. Among the approaches, 1.1% had contrary, 2.8% had mixed and 62.1% had complementary relationships. These results suggest that a broad-spectrum approach should be feasible from a safety standpoint. This novel approach has potential to be relatively inexpensive, it should help us address stages and types of cancer that lack conventional treatment, and it may reduce relapse risks. A proposed agenda for future research is offered.


Assuntos
Heterogeneidade Genética , Terapia de Alvo Molecular , Neoplasias/terapia , Medicina de Precisão , Antineoplásicos Fitogênicos/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/genética , Humanos , Neoplasias/genética , Neoplasias/patologia , Neoplasias/prevenção & controle , Transdução de Sinais , Microambiente Tumoral/genética
4.
Semin Cancer Biol ; 35 Suppl: S129-S150, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26454069

RESUMO

Cancer is a disease characterized by unrestrained cellular proliferation. In order to sustain growth, cancer cells undergo a complex metabolic rearrangement characterized by changes in metabolic pathways involved in energy production and biosynthetic processes. The relevance of the metabolic transformation of cancer cells has been recently included in the updated version of the review "Hallmarks of Cancer", where dysregulation of cellular metabolism was included as an emerging hallmark. While several lines of evidence suggest that metabolic rewiring is orchestrated by the concerted action of oncogenes and tumor suppressor genes, in some circumstances altered metabolism can play a primary role in oncogenesis. Recently, mutations of cytosolic and mitochondrial enzymes involved in key metabolic pathways have been associated with hereditary and sporadic forms of cancer. Together, these results demonstrate that aberrant metabolism, once seen just as an epiphenomenon of oncogenic reprogramming, plays a key role in oncogenesis with the power to control both genetic and epigenetic events in cells. In this review, we discuss the relationship between metabolism and cancer, as part of a larger effort to identify a broad-spectrum of therapeutic approaches. We focus on major alterations in nutrient metabolism and the emerging link between metabolism and epigenetics. Finally, we discuss potential strategies to manipulate metabolism in cancer and tradeoffs that should be considered. More research on the suite of metabolic alterations in cancer holds the potential to discover novel approaches to treat it.


Assuntos
Carcinogênese/metabolismo , Mitocôndrias/metabolismo , Neoplasias/metabolismo , Carcinogênese/genética , Proliferação de Células/genética , Transformação Celular Neoplásica/genética , Metabolismo Energético/genética , Epigênese Genética , Humanos , Redes e Vias Metabólicas/genética , Mitocôndrias/genética , Mitocôndrias/patologia , Neoplasias/genética , Neoplasias/patologia
5.
Liver Int ; 33(7): 1062-70, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23560860

RESUMO

BACKGROUND: Depression and anxiety are common in patients with nonalcoholic fatty liver disease (NAFLD). However, their associations with histological severity of NAFLD are unknown. AIM: This study examined the association(s) of depression, anxiety and antidepressant pharmacotherapy with severity of histological features in patients with NAFLD. METHODS: We analysed 567 patients with biopsy-proven NAFLD enrolled in the Duke NAFLD Clinical Database. Depressive and anxiety symptoms were assessed using the Hospital Anxiety & Depression Scale (HADS). The associations of depression and anxiety with severity of histological features of NAFLD were analysed using multiple logistic (or ordinal logistic) regression models with and without adjusting for confounding factors. RESULT: Subclinical and clinical depression was noted in 53% and 14% of patients respectively. Subclinical and clinical anxiety was noted in 45% and 25% of patients respectively. After adjusting for confounders, depression was significantly associated with more severe hepatocyte ballooning in a dose-dependent manner (likelihood ratio test, P = 0.0201); adjusted cumulative odds ratio (COR) of subclinical and clinical depression for having a higher grade of hepatocyte ballooning were 2.1 [95% CI, 1.0, 4.4] and 3.6 [95% CI, 1.4, 8.8]. CONCLUSIONS: In patients with NAFLD, depression was associated with more severe hepatocyte ballooning. Further investigation exploring pathobiological mechanisms underlying the observed associations and potential effects of antidepressant pharmacotherapy on NAFLD liver histology is warranted.


Assuntos
Antidepressivos/uso terapêutico , Ansiedade/etiologia , Depressão/tratamento farmacológico , Depressão/etiologia , Fígado Gorduroso/complicações , Adulto , Estudos Transversais , Feminino , Humanos , Funções Verossimilhança , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica , North Carolina , Razão de Chances , Inquéritos e Questionários
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