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1.
J Nutr ; 149(4): 667-675, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30770530

RESUMO

BACKGROUND: Differences in food composition, nutrient intake, and various health outcomes have been reported for vegetarians and non-vegetarians in the Adventist Health Study-2 (AHS-2) cohort. OBJECTIVE: We sought to determine whether biomarkers of dietary intake also differed between individuals classified as vegetarian (vegan, lacto-ovo-vegetarian, pesco-vegetarian, semi-vegetarian) and non-vegetarians based on patterns of consumption of meat, dairy, and eggs. METHODS: Fasting plasma, overnight urine, and adipose tissue samples were collected from a representative subset of AHS-2 participants classified into 5 diet groups (vegan, lacto-ovo-vegetarian, pesco-vegetarian, semi-vegetarian, non-vegetarian) who also completed food-frequency questionnaires. Diet-related biomarkers including carotenoids, isoflavones, enterolactone, saturated and polyunsaturated fatty acids, and vitamins were analyzed in 840 male and female participants. Multiple linear regression was used to examine the association between diet pattern and biomarker abundance, comparing each of 4 vegetarian dietary groups to non-vegetarians, and adjusted mean values were calculated. Bonferroni correction was applied to control for multiple testing. RESULTS: Vegans had higher plasma total carotenoid concentrations (1.6-fold, P < 0.0001), and higher excretion of urinary isoflavones (6-fold, P < 0.0001) and enterolactone (4.4-fold) compared with non-vegetarians. Vegans had lower relative abundance of saturated fatty acids including myristic, pentadecanoic, palmitic, and stearic acids (P < 0.0001). Vegans had higher linoleic acid (18:2ω-6) relative to non-vegetarians (23.3% compared with 19.1%) (P < 0.0001), and a higher proportion of total ω-3 fatty acids (2.1% compared with 1.6%) (P < 0.0001). Results overall were similar but less robust for lacto-ovo- and pesco-vegetarians. 1-Methylhistidine was 92% lower in vegans, and lower in lacto-ovo- and pesco-vegetarians by 90% and 80%, respectively, relative to non-vegetarians (P < 0.0001). CONCLUSION: AHS-2 participants following vegan, and lacto-ovo- or pesco-vegetarian diet patterns have significant differences in plasma, urine, and adipose tissue biomarkers associated with dietary intakes compared with those who consume a non-vegetarian diet. These findings provide some validation for the prior classification of dietary groups within the AHS-2 cohort.


Assuntos
Tecido Adiposo/química , Dieta , Vegetarianos , Tecido Adiposo/metabolismo , Idoso , Biomarcadores/sangue , Biomarcadores/urina , Estudos de Coortes , Feminino , Humanos , Estilo de Vida , Masculino , Pessoa de Meia-Idade
2.
Br J Nutr ; 120(6): 703-710, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30047347

RESUMO

The association between consumption of added or concentrated sugars and prostate cancer risk is unclear. We examined the association between concentrated sugars in beverages and desserts and prostate cancer risk among 22 720 men in the usual-care arm of the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial, enrolled during 1993-2001. After a median follow-up of 9 years, 1996 men were diagnosed with prostate cancer. Cox proportional hazards regression models were used to estimate hazard ratios (HR) for prostate cancer risk and 95 % CI, adjusting for potential confounding factors. Increased consumption of sugars from sugar-sweetened beverages was associated with increased risk of prostate cancer for men in the highest quartile of sugar consumption (HR: 1·21; 95 % CI 1·06, 1·39), and there was a linear trend (P<0·01). There were no linear associations between prostate cancer risk and consumption of sugars from fruit juices or dessert foods. In conclusion, in this prospective substudy within the PLCO trial, consumption of sugars from sugar-sweetened beverages was associated with increased risk of prostate cancer among men receiving standard medical care. Our study suggests that limiting intake of sugars from beverages may be important in the prevention of prostate cancer.


Assuntos
Bebidas/efeitos adversos , Dieta , Sacarose Alimentar/efeitos adversos , Comportamento Alimentar , Neoplasias da Próstata/etiologia , Edulcorantes/efeitos adversos , Idoso , Sacarose Alimentar/administração & dosagem , Sucos de Frutas e Vegetais , Humanos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Estudos Prospectivos , Neoplasias da Próstata/prevenção & controle , Fatores de Risco , Açúcares , Edulcorantes/administração & dosagem
3.
Cancer Causes Control ; 27(11): 1293-1300, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27539643

RESUMO

PURPOSE: The role of consumption of added sugars in cancers of the upper aerodigestive tract (UADT) is unclear. We examined associations between sugary beverages and susceptibility to UADT cancer as well as overall survival among UADT cancer patients. METHODS: The association between dietary added sugar and susceptibility to UADT cancers or overall survival among 601 UADT cancer cases was evaluated using data from a population-based case-control study conducted in Los Angeles County. Unconditional logistic regression was used to estimate odds ratios and 95 % confidence intervals (CI) for cancer susceptibility, and Cox regression was used to estimate hazards ratios (HRs) with 95 % CIs for survival, adjusting for relevant confounders. RESULTS: A total of 248 deaths were observed during follow-up (median 12.1 years). A positive association was observed with consumption of grams of sugar from beverages, including soft drinks and fruit juices, and poorer survival among UADT cancer cases (aHR, Q4 vs. Q1:1.88; 95 % CI 1.29, 2.72; p for trend = 0.002), as well as servings of sugary beverages (aHR, Q4 vs. Q1: 95 % CI 1.97, 95 % CI 1.32-2.93). This was due largely to consumption of sugars from soft drinks. Particularly, high consumption of sugary beverages was associated with poorer survival among esophageal cancer cases, driven by squamous cancers. No association was observed between sugary beverages and cancer susceptibility. CONCLUSION: These findings suggest that consumption of sugary beverages may decrease survival associated with UADT cancers. Additional studies should be conducted to examine survival among cancer patients consuming high amounts of added or refined sugars. Such studies may highlight prognostic factors for UADT cancers.


Assuntos
Bebidas/efeitos adversos , Sacarose Alimentar/efeitos adversos , Neoplasias Esofágicas/mortalidade , Neoplasias de Cabeça e Pescoço/mortalidade , Adulto , Estudos de Casos e Controles , Neoplasias Esofágicas/etiologia , Feminino , Neoplasias de Cabeça e Pescoço/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico
4.
Prostate ; 75(15): 1802-13, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26392321

RESUMO

INTRODUCTION: Prostate cancer that has metastasized to bone undergoes critical interactions with bone marrow stromal cells (BMSCs), ultimately promoting tumor survival. Previous studies have shown that BMSCs secrete factors that promote prostate cancer apoptosis or neuroendocrine differentiation. Because of the significance of transforming growth factor-ß (TGF-ß) family cytokines in cytostasis and bone metastasis, the role of TGF-ß signaling in the context of prostate cancer-BMSC interactions was investigated. METHODS: The role of TGF-ß family signaling in BMSC-induced apoptosis of lineage-related prostate cancer cells was investigated in live/dead assays. SMAD phosphorylation or activity during apoptosis and neuroendocrine differentiation was investigated using immunofluorescence, Western blotting, and luciferase reporter assays, along with the ALK-4, -5, -7 kinase inhibitor, SB-431542. RESULTS: Treatment of castration-resistant prostate cancer cells with SB-431542 resulted in significant reduction of apoptosis mediated by HS-5 BMSCs, supporting the involvement of TGF-ß/SMAD signaling during this event. Interestingly, however, pre-treatment of BMSCs with TGF-ß1 (5 ng/mL) yielded a conditioned medium that elicited a marked reduction in prostate cancer death. Phosphorylated-SMAD2 (P-SMAD2) was activated in BMSC-triggered transdifferentiated prostate cancer cells, as demonstrated through immunoblotting and luciferase reporter assays. However, SB-431542 did not restore androgen receptor and prostate specific antigen levels down-regulated by BMSC-secreted factors. Prostate cancer cells induced to undergo neuroendocrine differentiation in a BMSC-independent mechanism also showed elevated levels of P-SMAD2. DISCUSSION: Collectively, our findings indicate that: (1) TGF-ß family cytokines or regulated factors secreted from BMSCs are involved in prostate cancer apoptosis; (2) TGF-ß signaling in prostate cancer cells is induced during neuroendocrine differentiation; and (3) TGF-ß1 stimulation of BMSCs alters paracrine signaling to create a permissive environment for prostate cancer survival, suggesting a mechanism for prostate cancer-mediated colonization of bone. CONCLUSIONS: TGF-ß signaling resulting in activation of SMAD2 in prostate cancer may be an indicator of cellular stress in the presence of toxic paracrine factors released from the bone marrow stroma, ultimately fostering prostate cancer colonization of bone.


Assuntos
Apoptose/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Neoplasias de Próstata Resistentes à Castração/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fator de Crescimento Transformador beta1/metabolismo , Benzamidas/farmacologia , Linhagem Celular Tumoral , Dioxóis/farmacologia , Humanos , Masculino , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/patologia , Neoplasias de Próstata Resistentes à Castração/patologia , Receptores de Fatores de Crescimento Transformadores beta/antagonistas & inibidores , Fator de Crescimento Transformador beta1/efeitos dos fármacos
5.
J Nutr ; 149(10): 1870-1871, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31570946
6.
Sci Rep ; 13(1): 12593, 2023 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-37537165

RESUMO

Sialic acids (Sias) are a class of sugar molecules with a parent nine-carbon neuraminic acid, generally present at the ends of carbohydrate chains, either attached to cellular surfaces or as secreted glycoconjugates. Given their position and structural diversity, Sias modulate a wide variety of biological processes. However, little is known about the role of Sias in human adipose tissue, or their implications for health and disease, particularly among individuals following different dietary patterns. The goal of this study was to measure N-Acetylneuraminic acid (Neu5Ac), N-Glycolylneuraminic acid (Neu5Gc), and 2-keto-3-deoxy-D-glycero-D-galacto-nononic acid (KDN) concentrations in adipose tissue samples from participants in the Adventist Health Study-2 (AHS-2) and to compare the abundance of these Sias in individuals following habitual, long-term vegetarian or non-vegetarian dietary patterns. A method was successfully developed for the extraction and detection of Sias in adipose tissue. Sias levels were quantified in 52 vegans, 56 lacto-vegetarians, and 48 non-vegetarians using LC-MS/MS with Neu5Ac-D-1,2,3-13C3 as an internal standard. Dietary groups were compared using linear regression. Vegans and lacto-ovo-vegetarians had significantly higher concentrations of Neu5Ac relative to non-vegetarians. While KDN levels tended to be higher in vegans and lacto-ovo-vegetarians, these differences were not statistically significant. However, KDN levels were significantly inversely associated with body mass index. In contrast, Neu5Gc was not detected in human adipose samples. It is plausible that different Neu5Ac concentrations in adipose tissues of vegetarians, compared to those of non-vegetarians, reflect a difference in the baseline inflammatory status between the two groups. Epidemiologic studies examining levels of Sias in human adipose tissue and other biospecimens will help to further explore their roles in development and progression of inflammatory conditions and chronic diseases.


Assuntos
Ácidos Siálicos , Açúcares Ácidos , Humanos , Ácidos Siálicos/química , Cromatografia Líquida , Açúcares Ácidos/química , Espectrometria de Massas em Tandem , Tecido Adiposo , Dieta Vegetariana
7.
Prostate ; 72(12): 1339-50, 2012 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-22228025

RESUMO

BACKGROUND: Elevated TGF-ß levels are associated with prostate cancer progression. Although TGF-ß is a tumor suppressor for normal epithelial and early-stage cancer cells, it may act paradoxically as a tumor promoter in more advanced cancers, although its effects are largely cell and context dependent. This study analyzed prostate cancer responses to TGF-ß signaling in an isogenic model of androgen-sensitive and castration-resistant prostate cancer cells. METHODS: Phosphorylation and nuclear translocation of Smad2 and Smad3 were analyzed using immunoblotting. Proliferation and cell cycle responses to TGF-ß1 (5 ng/ml) were assessed using growth assays and flow cytometry for DNA content, as well as Western blot and immunoprecipitation of cell cycle proteins. RESULTS: Both androgen-sensitive (LNCaP) and castration-resistant (C4-2 and C4-2B) prostate cancer cell lines demonstrated TGF-ß1-induced phosphorylation and nuclear translocation of Smad2/3 that was robust in metastatic lines. Smad phosphorylation was completely abrogated with inhibition of ALK-5 kinase activity using the kinase inhibitor, SB-431542. Increased sensitivity to TGF-ß1-mediated growth inhibition was observed in C4-2 and C4-2B cells, as compared to LNCaP cells. This was paralleled with downregulation of Cyclin D and increased association of p15(Ink4b) or p27(Kip) with CDK's. Additionally, TGF-ß1 inhibited motility and invasion of metastatic cell lines. CONCLUSIONS: TGF-ß-mediated suppression of growth and motility is enhanced in metastatic, castration-resistant prostate cancer cells. Enhanced TGF-ß1-induced Smad2 and -3 signaling in prostate cancer cells may correlate with tumor suppressive activity. Therefore, the direct effects of TGF-ß1 on prostate cancer cells post-castration may be anti-tumorigenic and growth-suppressive.


Assuntos
Movimento Celular/fisiologia , Proliferação de Células , Inibidores do Crescimento/fisiologia , Neoplasias da Próstata/patologia , Transdução de Sinais/fisiologia , Proteína Smad2/fisiologia , Proteína Smad3/fisiologia , Fator de Crescimento Transformador beta1/fisiologia , Transporte Ativo do Núcleo Celular/fisiologia , Linhagem Celular Tumoral , Humanos , Masculino , Orquiectomia , Fosforilação/fisiologia , Neoplasias da Próstata/terapia , Regulação para Cima/fisiologia
8.
Nutrients ; 14(3)2022 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-35277064

RESUMO

It is unclear how vegetarian dietary patterns influence plasma metabolites involved in biological processes regulating chronic diseases. We sought to identify plasma metabolic profiles distinguishing vegans (avoiding meat, eggs, dairy) from non-vegetarians (consuming ≥28 g/day red meat) of the Adventist Health Study-2 cohort using global metabolomics profiling with ultra-performance liquid chromatography mass spectrometry (UPLC-MS/MS). Differences in abundance of metabolites or biochemical subclasses were analyzed using linear regression models, adjusting for surrogate and confounding variables, with cross-validation to simulate results from an independent sample. Random forest was used as a learning tool for classification, and principal component analysis was used to identify clusters of related metabolites. Differences in covariate-adjusted metabolite abundance were identified in over 60% of metabolites (586/930), after adjustment for false discovery. The vast majority of differentially abundant metabolites or metabolite subclasses showed lower abundance in vegans, including xanthine, histidine, branched fatty acids, acetylated peptides, ceramides, and long-chain acylcarnitines, among others. Many of these metabolite subclasses have roles in insulin dysregulation, cardiometabolic phenotypes, and inflammation. Analysis of metabolic profiles in vegans and non-vegetarians revealed vast differences in these two dietary groups, reflecting differences in consumption of animal and plant products. These metabolites serve as biomarkers of food intake, many with potential pathophysiological consequences for cardiometabolic diseases.


Assuntos
Dieta Vegana , Veganos , Animais , Cromatografia Líquida , Dieta Vegetariana , Humanos , Metabolômica/métodos , Espectrometria de Massas em Tandem , Vegetarianos
9.
Prostate ; 71(2): 157-67, 2011 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-20665531

RESUMO

BACKGROUND: Preferential bony metastasis of human prostate cancer (PCa) cells contributes to disease mortality and morbidity. Local factors in bone stromal extracellular matrix microenvironment affect tumor growth through paracrine interactions between tumor and stromal cells. METHODS: Using co-culture and medium transfer, we used several methods to assess interactions between PCa and bone stromal cells using three PCa cell lines: PC3, LNCaP, and the LNCaP derivative, C4-2B. RESULTS: Co-culture of LNCaP and C4-2B cells with bone marrow stromal cell lines, HS27a and HS5, decreased cell number, as did culture with conditioned medium (CM) harvested from these two cell lines suggesting a soluble paracrine factor was responsible. PC3 cell growth was unaffected. CM harvested from bone stromal cell lines triggered apoptosis in LNCaP and C4-2B cell lines, but not in PC3 cells. Surviving C4-2B cells grown in bone stromal cell CM over several days were growth arrested, suggesting presence of a growth inhibitor. Apoptosis induced by CM was dose-dependent. Flow cytometry demonstrated that over a 5-day culture period in stromal cell CM, LNCaP, and C4-2B cell lines, but not PC3 cells, underwent greater apoptosis than parallel cultures in SF medium. The LNCaP and C4-2B cells showed morphology and biomarker expression consistent with transdifferentiation towards a neuroendocrine phenotype after exposure to stromal cell CM. CONCLUSIONS: The reactive bone stromal microenvironment initially is hostile to PCa cells producing widespread apoptosis. Activation of transdifferentiation in a subset of apoptotic resistant cells may support phenotypic adaptation during disease progression in bone, eventually favoring lethal disease.


Assuntos
Apoptose/fisiologia , Células da Medula Óssea/metabolismo , Diferenciação Celular/fisiologia , Tumores Neuroendócrinos/patologia , Neoplasias da Próstata/patologia , Western Blotting , Células da Medula Óssea/patologia , Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/secundário , Processos de Crescimento Celular/fisiologia , Técnicas de Cocultura , Meios de Cultivo Condicionados , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Humanos , Masculino , Neoplasias Hormônio-Dependentes/metabolismo , Neoplasias Hormônio-Dependentes/patologia , Tumores Neuroendócrinos/metabolismo , Neoplasias da Próstata/metabolismo , Células Estromais/metabolismo , Células Estromais/patologia
11.
Nutrients ; 13(11)2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34836399

RESUMO

Plant-based diets, defined here as including both vegan and lacto-ovo-vegetarian diets, are growing in popularity throughout the Western world for various reasons, including concerns for human health and the health of the planet. Plant-based diets are more environmentally sustainable than meat-based diets and have a reduced environmental impact, including producing lower levels of greenhouse gas emissions. Dietary guidelines are normally formulated to enhance the health of society, reduce the risk of chronic diseases, and prevent nutritional deficiencies. We reviewed the scientific data on plant-based diets to summarize their preventative and therapeutic role in cardiovascular disease, cancer, diabetes, obesity, and osteoporosis. Consuming plant-based diets is safe and effective for all stages of the life cycle, from pregnancy and lactation, to childhood, to old age. Plant-based diets, which are high in fiber and polyphenolics, are also associated with a diverse gut microbiota, producing metabolites that have anti-inflammatory functions that may help manage disease processes. Concerns about the adequate intake of a number of nutrients, including vitamin B12, calcium, vitamin D, iron, zinc, and omega-3 fats, are discussed. The use of fortified foods and/or supplements as well as appropriate food choices are outlined for each nutrient. Finally, guidelines are suggested for health professionals working with clients consuming plant-based diets.


Assuntos
Doença Crônica/prevenção & controle , Dieta Vegana/normas , Dieta Vegetariana/normas , Dietética/normas , Política Nutricional , Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Gravidez , Adulto Jovem
12.
Nutrients ; 12(12)2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-33266012

RESUMO

We sought to determine if DNA methylation patterns differed between vegans and non-vegetarians in the Adventist Health Study-2 cohort. Genome-wide DNA methylation derived from buffy coat was profiled in 62 vegans and 142 non-vegetarians. Using linear regression, methylation of CpG sites and genes was categorized or summarized according to various genic/intergenic regions and CpG island-related regions, as well as the promoter. Methylation of genes was measured as the average methylation of available CpG's annotated to the nominated region of the respective gene. A permutation method defining the null distribution adapted from Storey et al. was used to adjust for false discovery. Differences in methylation of several CpG sites and genes were detected at a false discovery rate < 0.05 in region-specific and overall analyses. A vegan diet was associated predominantly with hypomethylation of genes, most notably methyltransferase-like 1 (METTL1). Although a limited number of differentially methylated features were detected in the current study, the false discovery method revealed that a much larger proportion of differentially methylated genes and sites exist, and could be detected with a larger sample size. Our findings suggest modest differences in DNA methylation in vegans and non-vegetarians, with a much greater number of detectable significant differences expected with a larger sample.


Assuntos
Metilação de DNA , Veganos , Negro ou Afro-Americano , Idoso , Índice de Massa Corporal , Estudos de Coortes , Dieta Vegana , Dieta Vegetariana , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Vegetarianos , População Branca
13.
Biophys J ; 96(5): 1733-50, 2009 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-19254534

RESUMO

Transforming growth factor beta (TGF-beta) signaling, which regulates multiple cellular processes including proliferation, apoptosis, and differentiation, plays an important but incompletely understood role in normal and cancerous tissues. For instance, although TGF-beta functions as a tumor suppressor in the premalignant stages of tumorigenesis, paradoxically, it also seems to act as a tumor promoter in advanced cancer leading to metastasis. The mechanisms by which TGF-beta elicits such diverse responses during cancer progression are still not entirely clear. As a first step toward understanding TGF-beta signaling quantitatively, we have developed a comprehensive, dynamic model of the canonical TGF-beta pathway via Smad transcription factors. By describing how an extracellular signal of the TGF-beta ligand is sensed by receptors and transmitted into the nucleus through intracellular Smad proteins, the model provides quantitative insight into how TGF-beta-induced responses are modulated and regulated. Subsequent model analysis shows that mechanisms associated with Smad activation by ligand-activated receptor, nuclear complex formation among Smad proteins, and inactivation of ligand-activated Smad (e.g., degradation, dephosphorylation) may be critical for regulating TGF-beta-targeted functional responses. The model was also used to predict dynamic characteristics of the Smad-mediated pathway in abnormal cells, from which we generated four testable hypotheses regarding potential mechanisms by which TGF-beta's tumor-suppressive roles may appear to morph into tumor-promotion during cancer progression.


Assuntos
Modelos Biológicos , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo , Transporte Ativo do Núcleo Celular , Algoritmos , Núcleo Celular/metabolismo , Expressão Gênica , Análise dos Mínimos Quadrados , Ligantes , Mutação , Neoplasias/metabolismo , Fosforilação , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Proteínas Smad/metabolismo
14.
Am J Clin Nutr ; 110(2): 377-390, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31175806

RESUMO

BACKGROUND: Microbial metabolism of lignans from high-fiber plant foods produces bioactive enterolignans, such as enterolactone (ENL) and enterodiol (END). Enterolignan exposure influences cellular pathways important to cancer risk and is associated with reduced colon tumorigenesis in animal models and lower colorectal cancer risk in humans. OBJECTIVES: The aim of this study was to test the effects of a flaxseed lignan supplement (50 mg secoisolariciresinol diglucoside/d) compared with placebo on host gene expression in colon biopsies and exfoliated colonocyte RNA in feces and fecal microbial community composition, and to compare responses in relation to ENL excretion. METHODS: We conducted a 2-period randomized, crossover intervention in 42 healthy men and women (20-45 y). We used RNA-seq to measure differentially expressed (DE) genes in colonic mucosa and fecal exfoliated cells through the use of edgeR and functional analysis with Ingenuity Pathway Analysis. We used 16S ribosomal RNA gene (V1-V3) analysis to characterize the fecal microbiome, and measured END and ENL in 24-h urine samples by gas chromatography-mass spectrometry. RESULTS: We detected 32 DE genes (false discovery rate <0.05) in the exfoliome, but none in the mucosal biopsies, in response to 60 d of lignan supplement compared with placebo. Statistically significant associations were detected between ENL excretion and fecal microbiome measured at baseline and at the end of the intervention periods. Further, we detected DE genes in colonic mucosa and exfoliome between low- and high-ENL excreters. Analysis of biopsy samples indicated that several anti-inflammatory upstream regulators, including transforming growth factor ß and interleukin 10 receptor, were suppressed in low-ENL excreters. Complementary analyses in exfoliated cells also suggested that low-ENL excreters may be predisposed to proinflammatory cellular events due to upregulation of nuclear transcription factor κB and NOS2, and an inhibition of the peroxisome proliferator-activated receptor γ network. CONCLUSIONS: These results suggest that ENL or other activities of the associated gut microbial consortia may modulate response to a dietary lignan intervention. This has important implications for dietary recommendations and chemoprevention strategies. This study was registered at clinicaltrials.gov as NCT01619020.


Assuntos
Fezes/microbiologia , Linho/química , Perfilação da Expressão Gênica , Mucosa Intestinal/efeitos dos fármacos , Lignanas/química , Extratos Vegetais/farmacologia , Adulto , Colo/efeitos dos fármacos , Estudos Cross-Over , Método Duplo-Cego , Feminino , Microbioma Gastrointestinal , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Mucosa Intestinal/metabolismo , Masculino , Extratos Vegetais/química
15.
Clin Exp Metastasis ; 25(4): 305-24, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-17906932

RESUMO

In order for cancer cells to successfully colonize a metastatic site, they must detach from the primary tumor using extracellular matrix-degrading proteases, intravasate and survive in the circulation, evade the immune response, and extravasate the vasculature to invade the target tissue parenchyma, where metastatic foci are established. Though many of the steps of metastasis are widely studied, the precise cellular interactions and molecular alterations associated with extravasation are unknown, and further study is needed to elucidate the mechanisms inherent to this process. Studies of leukocytes localized to inflamed tissue during the immune response may be used to elucidate the process of cancer extravasation, since leukocyte diapedesis through the vasculature involves critical adhesive interactions with endothelial cells, and both leukocytes and cancer cells express similar surface receptors capable of binding endothelial adhesion molecules. Thus, leukocyte extravasation during the inflammatory response has provided a model for transendothelial migration (TEM) of cancer cells. Leukocyte extravasation is characterized by a process whereby rolling mediated by cytokine-activated endothelial selectins is followed by firmer adhesions with beta1 and beta2 integrin subunits to an activated endothelium and subsequent diapedesis, which most likely involves activation of Rho GTPases, regulators of cytoskeletal rearrangements and motility. It is controversial whether such selectin-mediated rolling is necessary for TEM of cancer cells. However, it has been established that similar stable adhesions between tumor and endothelial cells precede cancer cell transmigration through the endothelium. Additionally, there is support for the preferential attachment of tumor cells to the endothelium and, accordingly, site-specific metastasis of cancer cells. Rho GTPases are critical to TEM of cancer cells as well, and some progress has been made in understanding the specific roles of the Rho GTPase family, though much is still unknown. As the mechanisms of cancer TEM are elucidated, new approaches to study and target metastasis may be utilized and developed.


Assuntos
Metástase Neoplásica , Células Neoplásicas Circulantes , Animais , Adesão Celular , Moléculas de Adesão Celular/fisiologia , Endotélio Vascular/fisiologia , Humanos , Leucócitos/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Selectinas/fisiologia , Proteínas rho de Ligação ao GTP/fisiologia
16.
Nutrients ; 9(4)2017 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-28417914

RESUMO

Some, but not all, epidemiologic studies report an association between vitamin D and prostate cancer risk. The inconsistent findings might be explained in the context of modification by members of the insulin-like growth factor (IGF) axis. Data and specimens for this nested case-control study (n = 1695 cases and n = 1682 controls) are from the Prostate Cancer Prevention Trial (PCPT). Baseline serum samples were assayed for 25(OH)D, IGF-1, IGF-2, IGFBP-2, IGFBP-3, and the ratio of IGF1:BP3, along with insulin-related markers c-peptide and leptin. The presence of prostate cancer was assessed by prostate biopsy. Multivariate logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (CIs) for prostate cancer risk. There were no interactions between serum 25(OH)D and IGF analytes in relation to prostate cancer risk when PCPT treatment arms were combined. In the placebo arm, above median serum 25(OH)D levels were associated with increased risk of prostate cancer among men with higher IGF-2 (OR:1.33, 95% CI: 1.00-1.65), with a significant interaction between 25(OH)D and treatment arm (Pinteraction = 0.04). Additionally, there was an interaction between treatment arm and serum IGFBP-3 (Pinteraction = 0.03). Higher serum 25(OH)D may increase risk of prostate cancer in the presence of higher circulating IGF-2.


Assuntos
Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Fator de Crescimento Insulin-Like II/metabolismo , Neoplasias da Próstata/sangue , Vitamina D/análogos & derivados , Idoso , Biópsia , Estudos de Casos e Controles , Humanos , Proteína 2 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Fator de Crescimento Insulin-Like I/metabolismo , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Neoplasias da Próstata/etiologia , Fatores de Risco , Vitamina D/sangue
17.
Food Funct ; 8(9): 3209-3218, 2017 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-28808723

RESUMO

Enterolignans, products of gut bacterial metabolism of plant lignans, have been associated with reduced risk of chronic diseases, but their association with other plasma metabolites is unknown. We examined plasma metabolite profiles according to urinary enterolignan excretion in a cross-sectional analysis using data from a randomized crossover, controlled feeding study. Eighty healthy adult males and females completed two 28-day feeding periods differing by glycemic load, refined carbohydrate, and fiber content. Lignan intake was calculated from food records using a polyphenol database. Targeted metabolomics was performed by LC-MS on plasma from fasting blood samples collected at the end of each feeding period. Enterolactone (ENL) and enterodiol, were measured in 24 h urine samples collected on the penultimate day of each study period using GC-MS. Linear mixed models were used to test the association between enterolignan excretion and metabolite abundances. Pathway analyses were conducted using the Global Test. Benjamini-Hochberg false discovery rate (FDR) was used to control for multiple testing. Of the metabolites assayed, 121 were detected in all samples. ENL excretion was associated positively with plasma hippuric acid and melatonin, and inversely with epinephrine, creatine, glycochenodeoxycholate, and glyceraldehyde (P < 0.05). Hippuric acid only satisfied the FDR of q < 0.1. END excretion was associated with myristic acid and glycine (q < 0.5). Two of 57 pathways tested were associated significantly with ENL, ubiquinone and terpenoid-quinone biosynthesis, and inositol phosphate metabolism. These results suggest a potential role for ENL or ENL-metabolizing gut bacteria in regulating plasma metabolites.


Assuntos
4-Butirolactona/análogos & derivados , Lignanas/sangue , Lignanas/urina , 4-Butirolactona/sangue , 4-Butirolactona/urina , Adulto , Estudos Cross-Over , Estudos Transversais , Fibras na Dieta/análise , Fibras na Dieta/metabolismo , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Fitoestrógenos , Extratos Vegetais
18.
Nutr Res ; 36(6): 620-6, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27188908

RESUMO

The effect of red and processed meats on cancer survival is unclear. We sought to examine the role of total and processed red meat consumption on all-cause mortality among patients with cancers of the upper aerodigestive tract (UADT) and lung, in order to test our hypothesis that red or processed meat was associated with overall mortality in these patients. Using data from a population-based case-control study conducted in Los Angeles County, we conducted a case-only analysis to examine the association of red or processed meat consumption on mortality after 12 years of follow-up, using a diet history questionnaire. Cox regression was used to estimate adjusted hazard ratios (HRs) with 95% confidence intervals (CIs), adjusting for potential confounders. Of 601 UADT cancer cases and 611 lung cancer cases, there were 248 and 406 deaths, respectively, yielding crude mortality rates of 0.07 and 0.12 deaths per year. Comparing the highest with lowest quartile of red meat consumption, the adjusted HR was 1.64 (95% CI, 1.04-2.57) among UADT cancer cases; for red or processed meat, the adjusted HR was 1.76 (95% CI, 1.10-2.82). A dose-response trend was observed. A weaker association was observed with red meat consumption and overall mortality among lung cancer cases. In conclusion, this case-only analysis demonstrated that increased consumption of red or processed meats was associated with mortality among UADT cancer cases and WAS weakly associated with mortality among lung cancer cases.


Assuntos
Neoplasias do Sistema Digestório/mortalidade , Neoplasias Pulmonares/mortalidade , Produtos da Carne/efeitos adversos , Carne Vermelha/efeitos adversos , Adolescente , Adulto , Idoso , Índice de Massa Corporal , Estudos de Casos e Controles , Estudos de Coortes , Dieta , Neoplasias do Sistema Digestório/etiologia , Feminino , Seguimentos , Humanos , Los Angeles , Neoplasias Pulmonares/etiologia , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Fatores de Risco , Fatores Socioeconômicos , Inquéritos e Questionários , Adulto Jovem
19.
J Biol Methods ; 2(3)2015.
Artigo em Inglês | MEDLINE | ID: mdl-26937420

RESUMO

The use of fluorogenic compounds in cell and molecular biology has increased in both frequency and range of applications. However, such compounds may introduce artifacts in intracellular fluorescence and cell number estimations as a consequence of interaction with exogenous stimulants, necessitating the use of adequate controls for accurate measurements and valid conclusions. Using calcein acetoxymethyl ester (AM) in combination with various exogenous cellular treatments, we report that the standard practice of direct normalization of experimental values to controls is insufficient for fluorogenic measurements. Treatments applied to cells may influence intracellular conversion of the fluorogenic compound, thereby enhancing or decreasing fluorescence relative to controls. We hereby encourage caution and recommend normalization of cellular fluorescence within each treatment group before comparison to controls.

20.
Int J Clin Exp Med ; 8(7): 11470-6, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26379965

RESUMO

The progression of prostate cancer is influenced by systemic inflammation, and may be attributed, in part, to genetic predisposition. Single nucleotide polymorphisms associated with the immune response may help mediate prostate cancer progression. We analyzed data from a hospital-based case-control study of 164 prostate cancer patients and 157 healthy male controls from the Memorial Sloan Kettering Cancer Center. We evaluated associations between six immunity-related polymorphisms (CRP rs1205 and rs1800947, FGFR2 rs1219648 and rs2981582, IFNGR1 rs11914, and IL10 rs1800871) and overall survival among prostate cancer patients, calculating adjusted hazard ratios (HR) and 95% confidence intervals (CI) using Cox proportional hazards regression. FGFR2 rs1219648 (GG vs. AA) and rs2981582 (TT vs. CC) polymorphisms were associated with more favorable overall survival (HR: 0.13, 95% CI: 0.03-0.62 and HR: 0.13, 95% CI: 0.03-0.53, respectively) in patients with primary prostate cancer. These observations highlight the need to validate and identify these and other immunity-related polymorphisms in larger studies examining survival of prostate cancer patients.

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