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1.
Nat Immunol ; 19(9): 932-941, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30127433

RESUMO

Cohesin is important for 3D genome organization. Nevertheless, even the complete removal of cohesin has surprisingly little impact on steady-state gene transcription and enhancer activity. Here we show that cohesin is required for the core transcriptional response of primary macrophages to microbial signals, and for inducible enhancer activity that underpins inflammatory gene expression. Consistent with a role for inflammatory signals in promoting myeloid differentiation of hematopoietic stem and progenitor cells (HPSCs), cohesin mutations in HSPCs led to reduced inflammatory gene expression and increased resistance to differentiation-inducing inflammatory stimuli. These findings uncover an unexpected dependence of inducible gene expression on cohesin, link cohesin with myeloid differentiation, and may help explain the prevalence of cohesin mutations in human acute myeloid leukemia.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Diferenciação Celular/genética , Autorrenovação Celular/genética , Proteínas Cromossômicas não Histona/metabolismo , Células-Tronco Hematopoéticas/fisiologia , Leucemia Mieloide Aguda/genética , Macrófagos/fisiologia , Proteínas Nucleares/genética , Fosfoproteínas/genética , Animais , Proteínas de Ciclo Celular/genética , Células Cultivadas , Proteínas Cromossômicas não Histona/genética , Proteínas de Ligação a DNA , Regulação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Inflamação/genética , Lipopolissacarídeos/imunologia , Camundongos , Camundongos Knockout , Mutação/genética , Coesinas
2.
Nature ; 621(7980): 821-829, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37586410

RESUMO

Endothelial cells line the blood and lymphatic vasculature, and act as an essential physical barrier, control nutrient transport, facilitate tissue immunosurveillance and coordinate angiogenesis and lymphangiogenesis1,2. In the intestine, dietary and microbial cues are particularly important in the regulation of organ homeostasis. However, whether enteric endothelial cells actively sense and integrate such signals is currently unknown. Here we show that the aryl hydrocarbon receptor (AHR) acts as a critical node for endothelial cell sensing of dietary metabolites in adult mice and human primary endothelial cells. We first established a comprehensive single-cell endothelial atlas of the mouse small intestine, uncovering the cellular complexity and functional heterogeneity of blood and lymphatic endothelial cells. Analyses of AHR-mediated responses at single-cell resolution identified tissue-protective transcriptional signatures and regulatory networks promoting cellular quiescence and vascular normalcy at steady state. Endothelial AHR deficiency in adult mice resulted in dysregulated inflammatory responses and the initiation of proliferative pathways. Furthermore, endothelial sensing of dietary AHR ligands was required for optimal protection against enteric infection. In human endothelial cells, AHR signalling promoted quiescence and restrained activation by inflammatory mediators. Together, our data provide a comprehensive dissection of the effect of environmental sensing across the spectrum of enteric endothelia, demonstrating that endothelial AHR signalling integrates dietary cues to maintain tissue homeostasis by promoting endothelial cell quiescence and vascular normalcy.


Assuntos
Células Endoteliais , Receptores de Hidrocarboneto Arílico , Humanos , Animais , Camundongos , Receptores de Hidrocarboneto Arílico/metabolismo , Células Endoteliais/metabolismo , Intestinos , Transdução de Sinais , Homeostase , Ligantes
3.
Nature ; 600(7890): 737-742, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34880491

RESUMO

Stability of the epigenetic landscape underpins maintenance of the cell-type-specific transcriptional profile. As one of the main repressive epigenetic systems, DNA methylation has been shown to be important for long-term gene silencing; its loss leads to ectopic and aberrant transcription in differentiated cells and cancer1. The developing mouse germ line endures global changes in DNA methylation in the absence of widespread transcriptional activation. Here, using an ultra-low-input native chromatin immunoprecipitation approach, we show that following DNA demethylation the gonadal primordial germ cells undergo remodelling of repressive histone modifications, resulting in a sex-specific signature in mice. We further demonstrate that Polycomb has a central role in transcriptional control in the newly hypomethylated germline genome as the genetic loss of Ezh2 leads to aberrant transcriptional activation, retrotransposon derepression and dramatic loss of developing female germ cells. This sex-specific effect of Ezh2 deletion is explained by the distinct landscape of repressive modifications observed in male and female germ cells. Overall, our study provides insight into the dynamic interplay between repressive chromatin modifications in the context of a developmental reprogramming system.


Assuntos
Montagem e Desmontagem da Cromatina , Células Germinativas , Animais , Cromatina/genética , Cromatina/metabolismo , Imunoprecipitação da Cromatina , Metilação de DNA , Epigênese Genética , Feminino , Células Germinativas/metabolismo , Masculino , Camundongos , Proteínas do Grupo Polycomb/metabolismo
4.
Nature ; 580(7802): 263-268, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32269334

RESUMO

In cells, organs and whole organisms, nutrient sensing is key to maintaining homeostasis and adapting to a fluctuating environment1. In many animals, nutrient sensors are found within the enteroendocrine cells of the digestive system; however, less is known about nutrient sensing in their cellular siblings, the absorptive enterocytes1. Here we use a genetic screen in Drosophila melanogaster to identify Hodor, an ionotropic receptor in enterocytes that sustains larval development, particularly in nutrient-scarce conditions. Experiments in Xenopus oocytes and flies indicate that Hodor is a pH-sensitive, zinc-gated chloride channel that mediates a previously unrecognized dietary preference for zinc. Hodor controls systemic growth from a subset of enterocytes-interstitial cells-by promoting food intake and insulin/IGF signalling. Although Hodor sustains gut luminal acidity and restrains microbial loads, its effect on systemic growth results from the modulation of Tor signalling and lysosomal homeostasis within interstitial cells. Hodor-like genes are insect-specific, and may represent targets for the control of disease vectors. Indeed, CRISPR-Cas9 genome editing revealed that the single hodor orthologue in Anopheles gambiae is an essential gene. Our findings highlight the need to consider the instructive contributions of metals-and, more generally, micronutrients-to energy homeostasis.


Assuntos
Canais de Cloreto/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/crescimento & desenvolvimento , Drosophila melanogaster/metabolismo , Ingestão de Alimentos/fisiologia , Intestinos/fisiologia , Zinco/metabolismo , Animais , Drosophila melanogaster/genética , Enterócitos/metabolismo , Feminino , Preferências Alimentares , Homeostase , Insetos Vetores , Insulina/metabolismo , Ativação do Canal Iônico , Larva/genética , Larva/crescimento & desenvolvimento , Larva/metabolismo , Lisossomos/metabolismo , Masculino , Oócitos/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Transdução de Sinais , Xenopus
5.
Cereb Cortex ; 33(20): 10711-10721, 2023 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-37679857

RESUMO

Pain-related aversive memory is common in chronic pain patients. Electroacupuncture has been demonstrated to block pain-related aversive memory. The insular cortex is a key region closely related to aversive behaviors. In our study, a potential mechanism underlying the effect of electroacupuncture treatment on pain-related aversive memory behaviors relative to the insular cortex was investigated. Our study used the chemogenetic method, pharmacological method, electroacupuncture intervention, and behavioral detection. Our study showed that both inhibition of gamma-aminobutyric acidergic neurons and activation of the kappa opioid receptor in the insular cortex blocked the pain-related aversive memory behaviors induced by 2 crossover injections of carrageenan in mice; conversely, both the activation of gamma-aminobutyric acidergic neurons and inhibition of kappa opioid receptor in the insular cortex play similar roles in inducing pain-related aversive memory behaviors following 2 crossover injections of carrageenan. In addition, activation of gamma-aminobutyric acidergic neurons in the insular cortex reversed the effect of kappa opioid receptor activation in the insular cortex. Moreover, electroacupuncture effectively blocked pain-related aversive memory behaviors in model mice, which was reversed by both activation of gamma-aminobutyric acidergic neurons and inhibition of kappa opioid receptor in the insular cortex. The effect of electroacupuncture on blocking pain-related aversive memory behaviors may be related to the activation of the kappa opioid receptor and inhibition of gamma-aminobutyric acidergic neurons in the insular cortex.


Assuntos
Dor Crônica , Eletroacupuntura , Camundongos , Humanos , Animais , Receptores Opioides kappa/metabolismo , Córtex Insular , Carragenina/toxicidade , Neurônios GABAérgicos/fisiologia , Ácido gama-Aminobutírico/farmacologia , Doença Crônica , Recidiva
6.
Nucleic Acids Res ; 50(6): 3379-3393, 2022 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-35293570

RESUMO

Pre-mRNA processing is an essential mechanism for the generation of mature mRNA and the regulation of gene expression in eukaryotic cells. While defects in pre-mRNA processing have been implicated in a number of diseases their involvement in metabolic pathologies is still unclear. Here, we show that both alternative splicing and alternative polyadenylation, two major steps in pre-mRNA processing, are significantly altered in non-alcoholic fatty liver disease (NAFLD). Moreover, we find that Serine and Arginine Rich Splicing Factor 10 (SRSF10) binding is enriched adjacent to consensus polyadenylation motifs and its expression is significantly decreased in NAFLD, suggesting a role mediating pre-mRNA dysregulation in this condition. Consistently, inactivation of SRSF10 in mouse and human hepatocytes in vitro, and in mouse liver in vivo, was found to dysregulate polyadenylation of key metabolic genes such as peroxisome proliferator-activated receptor alpha (PPARA) and exacerbate diet-induced metabolic dysfunction. Collectively our work implicates dysregulated pre-mRNA polyadenylation in obesity-induced liver disease and uncovers a novel role for SRSF10 in this process.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Hepatopatia Gordurosa não Alcoólica , Poliadenilação , Proteínas Repressoras/metabolismo , Fatores de Processamento de Serina-Arginina/metabolismo , Animais , Hepatócitos/metabolismo , Humanos , Fígado/metabolismo , Camundongos , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/patologia , Precursores de RNA/genética , Precursores de RNA/metabolismo , Splicing de RNA
7.
Eur Arch Otorhinolaryngol ; 281(5): 2441-2450, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38180607

RESUMO

OBJECTIVE: The primary objective of this study was to find the association between dietary zinc intake and the prevalence of olfactory disorders using data from the National Health and Nutrition Examination Survey (NHANES). METHODS: A cross-sectional study was conducted using the 2013-2014 NHANES data. A linear regression model was constructed with dietary zinc intake as the independent variable and olfactory dysfunction as the dependent variable. Initially, in the unadjusted model, weighted logistic regression analysis was carried out for continuous variables, and stratified analysis was conducted for categorical variables. Subsequently, three models were created to perform subgroup analysis by adjusting for different confounding factors, further investigating the relationship between dietary zinc intake and olfactory dysfunction. Finally, restricted cubic spline (RCS) models adjusting for all confounding factors were utilized to study the nonlinear associations of age and dietary zinc intake with olfactory dysfunction and their relevant thresholds. RESULTS: A total of 2958 samples were analyzed in this study. Weighted logistic regression analysis displayed a negative relationship between dietary zinc intake and the prevalence of olfactory dysfunction in the population of non-Hispanic whites and other Hispanics, as well as in individuals with body mass index (BMI) ≥ 25 kg/m2 (OR < 1, P < 0.05). The P values for the multiplicative interaction terms adjusting for all confounding factors were not significant (P for interaction > 0.05). In the three regression models adjusting for different confounding factors, dietary zinc intake was significantly negatively related to olfactory dysfunction in all populations (Crude: OR 0.63, 95% CI 0.44-0.91; Model I: OR 0.58, 95% CI 0.38-0.90; Model II: OR 0.59, 95% CI 0.35-1.00). Subgroup analysis based on BMI showed a remarkable negative relationship between dietary zinc intake and olfactory dysfunction in the group with BMI of 25-30 kg/m2 (Crude: OR 0.50, 95% CI 0.28-0.90, P = 0.012; Model I: OR 0.49, 95% CI 0.24-1.00, P = 0.021) and the group with BMI ≥ 30 kg/m2 (Crude: OR 0.55, 95% CI 0.33-0.92, P = 0.013; Model I: OR 0.51, 95% CI 0.29-0.88, P = 0.005; Model II: OR 0.51, 95% CI 0.29-0.91, P = 0.004). RCS analysis revealed a remarkable nonlinear association of age and dietary zinc intake with olfactory dysfunction (P-non-linear < 0.05). The prevalence of olfactory dysfunction was considerably higher in individuals aged 60 and above compared to those under 60 years old. Daily dietary zinc intake within the range of 9.60-17.45 mg was a protective factor for olfactory dysfunction, while intake outside this range increased the prevalence of olfactory dysfunction. CONCLUSION: Daily dietary zinc intake within the range of 9.60-17.45 mg has a protective effect against olfactory dysfunction. Intake outside this range increases the prevalence of olfactory dysfunction. The prevalence of olfactory dysfunction is significantly higher in individuals aged 60 and above compared to those under 60 years old. For individuals with a BMI of 25-30 kg/m2 and a BMI ≥ 30 kg/m2, dietary zinc intake is negatively correlated with olfactory dysfunction. Therefore, it is recommended that these populations increase their dietary zinc intake to develop healthier lifestyles and maintain olfactory health.


Assuntos
Transtornos do Olfato , Zinco , Humanos , Pessoa de Meia-Idade , Inquéritos Nutricionais , Estudos Transversais , Dieta , Transtornos do Olfato/epidemiologia
8.
Int J Mol Sci ; 25(4)2024 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-38397056

RESUMO

The development of acquired resistance to small molecule tyrosine kinase inhibitors (TKIs) targeting epidermal growth factor receptor (EGFR) signaling has hindered their efficacy in treating non-small cell lung cancer (NSCLC) patients. Our previous study showed that constitutive activation of the 70 kDa ribosomal protein S6 kinase 1 (S6K1) contributes to the acquired resistance to EGFR-TKIs in NSCLC cell lines and xenograft tumors in nude mice. However, the regulatory mechanisms underlying S6K1 constitutive activation in TKI-resistant cancer cells have not yet been explored. In this study, we recapitulated this finding by taking advantage of a gefitinib-resistant patient-derived xenograft (PDX) model established through a number of passages in mice treated with increasing doses of gefitinib. The dissociated primary cells from the resistant PDX tumors (PDX-R) displayed higher levels of phosphor-S6K1 expression and were resistant to gefitinib compared to cells from passage-matched parental PDX tumors (PDX-P). Both genetic and pharmacological inhibition of S6K1 increased sensitivity to gefitinib in PDX-R cells. In addition, both total and phosphorylated mechanistic target of rapamycin kinase (MTOR) levels were upregulated in PDX-R and gefitinib-resistant PC9G cells. Knockdown of MTOR by siRNA decreased the expression levels of total and phosphor-S6K1 and increased sensitivity to gefitinib in PDX-R and PC9G cells. Moreover, a transcription factor ELK1, which has multiple predicted binding sites on the MTOR promoter, was also upregulated in PDX-R and PC9G cells, while the knockdown of ELK1 led to decreased expression of MTOR and S6K1. The chromatin immunoprecipitation (ChIP)-PCR assay showed the direct binding between ELK1 and the MTOR promoter, and the luciferase reporter assay further indicated that ELK1 could upregulate MTOR expression through tuning up its transcription. Silencing ELK1 via siRNA transfection improved the efficacy of gefitinib in PDX-R and PC9G cells. These results support the notion that activation of ELK1/MTOR/S6K1 signaling contributes to acquired resistance to gefitinib in NSCLC. The findings in this study shed new light on the mechanism for acquired EGFR-TKI resistance and provide potential novel strategies by targeting the ELK1/MTOR/S6K1 pathway.


Assuntos
Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas , Gefitinibe , Neoplasias Pulmonares , Proteínas Elk-1 do Domínio ets , Animais , Humanos , Camundongos , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Proliferação de Células , Resistencia a Medicamentos Antineoplásicos/genética , Receptores ErbB/metabolismo , Gefitinibe/farmacologia , Gefitinibe/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Camundongos Nus , Proteínas Quinases S6 Ribossômicas , RNA Interferente Pequeno/farmacologia , Sirolimo/farmacologia , Serina-Treonina Quinases TOR/metabolismo , /uso terapêutico
9.
J Physiol ; 601(1): 83-98, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36420836

RESUMO

Autosomal dominant polycystic kidney disease is caused by mutations in the membrane receptor PKD1 or the cation channel PKD2. TACAN (also termed TMEM120A), recently reported as an ion channel in neurons for mechanosensing and pain sensing, is also distributed in diverse non-neuronal tissues, such as kidney, heart and intestine, suggesting its involvement in other functions. In this study, we found that TACAN is in a complex with PKD2 in native renal cell lines. Using the two-electrode voltage clamp in Xenopus oocytes, we found that TACAN inhibits the channel activity of PKD2 gain-of-function mutant F604P. TACAN fragments containing the first and last transmembrane domains interacted with the PKD2 C- and N-terminal fragments, respectively. The TACAN N-terminus acted as a blocking peptide, and TACAN inhibited the function of PKD2 by the binding of PKD2 with TACAN. By patch clamping in mammalian cells, we found that TACAN inhibits both the single-channel conductance and the open probability of PKD2 and mutant F604P. PKD2 co-expressed with TACAN, but not PKD2 alone, exhibited pressure sensitivity. Furthermore, we found that TACAN aggravates PKD2-dependent tail curvature and pronephric cysts in larval zebrafish. In summary, this study revealed that TACAN acts as a PKD2 inhibitor and mediates mechanosensitivity of the PKD2-TACAN channel complex. KEY POINTS: TACAN inhibits the function of PKD2 in vitro and in vivo. TACAN N-terminal S1-containing fragment T160X interacts with the PKD2 C-terminal fragment N580-L700, and its C-terminal S6-containing fragment L296-D343 interacts with the PKD2 N-terminal A594X. TACAN inhibits the function of the PKD2 channel by physical interaction. The complex of PKD2 with TACAN, but not PKD2 alone, confers mechanosensitivity.


Assuntos
Rim Policístico Autossômico Dominante , Peixe-Zebra , Animais , Canais de Cátion TRPP/genética , Canais de Cátion TRPP/metabolismo , Canais Iônicos/genética , Rim Policístico Autossômico Dominante/genética , Rim Policístico Autossômico Dominante/metabolismo , Rim/metabolismo , Mamíferos/metabolismo
10.
J Immunol ; 207(12): 2976-2991, 2021 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-34810221

RESUMO

RUNX1 is a transcription factor that plays key roles in hematopoietic development and in hematopoiesis and lymphopoiesis. In this article, we report that RUNX1 regulates a gene expression program in naive mouse B cells that affects the dynamics of cell cycle entry in response to stimulation of the BCR. Conditional knockout of Runx1 in mouse resting B cells resulted in accelerated entry into S-phase after BCR engagement. Our results indicate that Runx1 regulates the cyclin D2 (Ccnd2) gene, the immediate early genes Fosl2, Atf3, and Egr2, and the Notch pathway gene Rbpj in mouse B cells, reducing the rate at which transcription of these genes increases after BCR stimulation. RUNX1 interacts with the chromatin remodeler SNF-2-related CREB-binding protein activator protein (SRCAP), recruiting it to promoter and enhancer regions of the Ccnd2 gene. BCR-mediated activation triggers switching between binding of RUNX1 and its paralog RUNX3 and between SRCAP and the switch/SNF remodeling complex member BRG1. Binding of BRG1 is increased at the Ccnd2 and Rbpj promoters in the Runx1 knockout cells after BCR stimulation. We also find that RUNX1 exerts positive or negative effects on a number of genes that affect the activation response of mouse resting B cells. These include Cd22 and Bank1, which act as negative regulators of the BCR, and the IFN receptor subunit gene Ifnar1 The hyperresponsiveness of the Runx1 knockout B cells to BCR stimulation and its role in regulating genes that are associated with immune regulation suggest that RUNX1 could be involved in regulating B cell tolerance.


Assuntos
Linfócitos B , Subunidade alfa 2 de Fator de Ligação ao Core , Animais , Linfócitos B/metabolismo , Ciclo Celular/genética , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Hematopoese , Camundongos , Regiões Promotoras Genéticas
11.
J Formos Med Assoc ; 122(10): 1001-1007, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37142476

RESUMO

BACKGROUND: /Purpose: Reactivity at the Bacillus Calmette-Guérin (BCG) scar is a pathognomonic feature of Kawasaki disease (KD). However, its value in predicting KD outcomes has not been emphasized. This study explored the clinical significance of BCG scar redness with respect to coronary artery outcomes. METHODS: This retrospective study collected data on children with KD from 13 hospitals in Taiwan during 2019-2021. Children with KD were categorized into four groups based on the KD type and BCG scar reactivity. Risk factors of coronary artery abnormalities (CAA) were analyzed in all groups. RESULTS: BCG scar redness occurred in 49% of 388 children with KD. BCG scar redness was associated with younger age, early intravenous immunoglobulin (IVIG) treatment, hypoalbuminemia, and CAA at the first echocardiogram (p < 0.01). BCG scar redness (RR 0.56) and pyuria (RR 2.61) were independent predictors of any CAA within 1 month (p < 0.05). Moreover, pyuria (RR 5.85, p < 0.05) in children with complete KD plus BCG scar redness was associated with CAA at 2-3 months; first IVIG resistance (RR 15.2) and neutrophil levels ≥80% (RR 8.37) in children with complete KD plus BCG scar non-redness were associated with CAA at 2-3 months (p < 0.05). We failed to detect any significant risk factors of CAA at 2-3 months in children with incomplete KD. CONCLUSION: BCG scar reactivity contributes to diverse clinical features in KD. It can be effectively applied to determine the risk factors of any CAA within 1 month and CAA at 2-3 months.


Assuntos
Vacina BCG , Doença da Artéria Coronariana , Síndrome de Linfonodos Mucocutâneos , Piúria , Criança , Humanos , Lactente , Vacina BCG/efeitos adversos , Cicatriz/complicações , Cicatriz/tratamento farmacológico , Doença da Artéria Coronariana/tratamento farmacológico , Imunoglobulinas Intravenosas/uso terapêutico , Síndrome de Linfonodos Mucocutâneos/complicações , Piúria/complicações , Piúria/tratamento farmacológico , Estudos Retrospectivos
12.
Int J Mol Sci ; 24(22)2023 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-38003694

RESUMO

Epithelial ovarian cancer (EOC) is a lethal gynecological cancer, of which paclitaxel resistance is the major factor limiting treatment outcomes, and identification of paclitaxel resistance-related genes is arduous. We obtained transcriptomic data from seven paclitaxel-resistant ovarian cancer cell lines and corresponding sensitive cell lines. Define genes significantly up-regulated in at least three resistant cell lines, meanwhile they did not down-regulate in the other resistant cell lines as candidate genes. Candidate genes were then ranked according to the frequencies of significant up-regulation in resistant cell lines, defining genes with the highest rankings as paclitaxel resistance-related genes (PRGs). Patients were grouped based on the median expression of PRGs. The lipid metabolism-related gene set and the oncological gene set were established and took intersections with genes co-upregulated with PRGs, obtaining 229 co-upregulated genes associated with lipid metabolism and tumorigenesis. The PPI network obtained 19 highly confidential synergistic targets (interaction score > 0.7) that directly associated with CPT1A. Finally, FASN and SCD were up-stream substrate provider and competitor of CPT1A, respectively. Western blot and qRT-PCR results confirmed the over-expression of CPT1A, SCD and FASN in the A2780/PTX cell line. The inhibition of CPT1A, SCD and FASN down-regulated cell viability and migration, pharmacological blockade of CPT1A and SCD increased apoptosis rate and paclitaxel sensitivity of A2780/PTX. In summary, our novel bioinformatic methods can overcome difficulties in drug resistance evaluation, providing promising therapeutical strategies for paclitaxel-resistant EOC via taregting lipid metabolism-related enzymes.


Assuntos
Neoplasias Ovarianas , Paclitaxel , Humanos , Feminino , Paclitaxel/farmacologia , Paclitaxel/uso terapêutico , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Linhagem Celular Tumoral , Metabolismo dos Lipídeos/genética , Resistencia a Medicamentos Antineoplásicos/genética , Carcinoma Epitelial do Ovário/tratamento farmacológico , Carcinoma Epitelial do Ovário/genética , Apoptose/genética , Ácido Graxo Sintase Tipo I/metabolismo
13.
J Appl Clin Med Phys ; 23(7): e13595, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35332646

RESUMO

PURPOSE: Dose computation using cone beam computed tomography (CBCT) images is inaccurate for the purpose of adaptive treatment planning. The main goal of this study is to assess the dosimetric accuracy of synthetic computed tomography (CT)-based calculation for adaptive planning in the upper abdominal region. We hypothesized that deep learning-based synthetically generated CT images will produce comparable results to a deformed CT (CTdef) in terms of dose calculation, while displaying a more accurate representation of the daily anatomy and therefore superior dosimetric accuracy. METHODS: We have implemented a cycle-consistent generative adversarial networks (CycleGANs) architecture to synthesize CT images from the daily acquired CBCT image with minimal error. CBCT and CT images from 17 liver stereotactic body radiation therapy (SBRT) patients were used to train, test, and validate the algorithm. RESULTS: The synthetically generated images showed increased signal-to-noise ratio, contrast resolution, and reduced root mean square error, mean absolute error, noise, and artifact severity. Superior edge matching, sharpness, and preservation of anatomical structures from the CBCT images were observed for the synthetic images when compared to the CTdef registration method. Three verification plans (CBCT, CTdef, and synthetic) were created from the original treatment plan and dose volume histogram (DVH) statistics were calculated. The synthetic-based calculation shows comparatively similar results to the CTdef-based calculation with a maximum mean deviation of 1.5%. CONCLUSIONS: Our findings show that CycleGANs can produce reliable synthetic images for the adaptive delivery framework. Dose calculations can be performed on synthetic images with minimal error. Additionally, enhanced image quality should translate into better daily alignment, increasing treatment delivery accuracy.


Assuntos
Aprendizado Profundo , Planejamento da Radioterapia Assistida por Computador , Tomografia Computadorizada de Feixe Cônico/métodos , Humanos , Processamento de Imagem Assistida por Computador/métodos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Tomografia Computadorizada por Raios X
14.
Int J Mol Sci ; 23(12)2022 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-35743145

RESUMO

The diverse repertoires of cellular mechanisms that progress certain cancer types are being uncovered by recent research and leading to more effective treatment options. Ovarian cancer (OC) is among the most difficult cancers to treat. OC has limited treatment options, especially for patients diagnosed with late-stage OC. The dysregulation of miRNAs in OC plays a significant role in tumorigenesis through the alteration of a multitude of molecular processes. The development of OC can also be due to the utilization of endogenously derived reactive oxygen species (ROS) by activating signaling pathways such as PI3K/AKT and MAPK. Both miRNAs and ROS are involved in regulating OC angiogenesis through mediating multiple angiogenic factors such as hypoxia-induced factor (HIF-1) and vascular endothelial growth factor (VEGF). The NAPDH oxidase subunit NOX4 plays an important role in inducing endogenous ROS production in OC. This review will discuss several important miRNAs, NOX4, and ROS, which contribute to therapeutic resistance in OC, highlighting the effective therapeutic potential of OC through these mechanisms.


Assuntos
MicroRNAs , Neoplasias Ovarianas , Carcinoma Epitelial do Ovário , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia , MicroRNAs/genética , NADPH Oxidases/metabolismo , Neovascularização Patológica/genética , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Fosfatidilinositol 3-Quinases , Espécies Reativas de Oxigênio/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
15.
Mol Biol Evol ; 37(7): 1986-2001, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32145025

RESUMO

Genetic variation in the enzymes that catalyze posttranslational modification of proteins is a potentially important source of phenotypic variation during evolution. Ubiquitination is one such modification that affects turnover of virtually all of the proteins in the cell in addition to roles in signaling and epigenetic regulation. UBE2D3 is a promiscuous E2 enzyme, which acts as an ubiquitin donor for E3 ligases that catalyze ubiquitination of developmentally important proteins. We have used protein sequence comparison of UBE2D3 orthologs to identify a position in the C-terminal α-helical region of UBE2D3 that is occupied by a conserved serine in amniotes and by alanine in anamniote vertebrate and invertebrate lineages. Acquisition of the serine (S138) in the common ancestor to modern amniotes created a phosphorylation site for Aurora B. Phosphorylation of S138 disrupts the structure of UBE2D3 and reduces the level of the protein in mouse embryonic stem cells (ESCs). Substitution of S138 with the anamniote alanine (S138A) increases the level of UBE2D3 in ESCs as well as being a gain of function early embryonic lethal mutation in mice. When mutant S138A ESCs were differentiated into extraembryonic primitive endoderm, levels of the PDGFRα and FGFR1 receptor tyrosine kinases were reduced and primitive endoderm differentiation was compromised. Proximity ligation analysis showed increased interaction between UBE2D3 and the E3 ligase CBL and between CBL and the receptor tyrosine kinases. Our results identify a sequence change that altered the ubiquitination landscape at the base of the amniote lineage with potential effects on amniote biology and evolution.


Assuntos
Endoderma/enzimologia , Evolução Molecular , Proteínas Proto-Oncogênicas c-cbl/metabolismo , Enzimas de Conjugação de Ubiquitina/genética , Vertebrados/genética , Substituição de Aminoácidos , Animais , Aurora Quinase B/metabolismo , Feminino , Humanos , Camundongos , Fosforilação , Receptores Proteína Tirosina Quinases/metabolismo , Enzimas de Conjugação de Ubiquitina/metabolismo , Vertebrados/metabolismo
16.
J Appl Clin Med Phys ; 22(5): 24-35, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33792180

RESUMO

PURPOSE: Two-dimensional (2D) IMRT QA has been widely performed in Radiation Oncology clinic. However, concerns regarding its sensitivity in detecting delivery errors and its clinical meaning have been raised in publications. In this study, a robust methodology of three-dimensional (3D) IMRT QA using fiducial registration and structure-mapping was proposed to acquire organ-specific dose information. METHODS: Computed tomography (CT) markers were placed on the PRESAGE dosimeter as fiducials before CT simulation. Subsequently, the images were transferred to the treatment planning system to create a verification plan for the examined treatment plan. Patient's CT images were registered to the CT images of the dosimeter for structure mapping according to the positions of the fiducials. After irradiation, the 3D dose distribution was read-out by an optical-CT (OCT) scanner with fiducials shown on the OCT dose images. An automatic localization algorithm was developed in MATLAB to register the markers in the OCT images to those in the CT images of the dosimeter. SlicerRT was used to show and analyze the results. Fiducial registration error was acquired by measuring the discrepancies in 20 fiducial registrations, and thus the fiducial localization error and target registration error (TRE) was estimated. RESULTS: Dosimetry comparison between the calculated and measured dose distribution in various forms were presented, including 2D isodose lines comparison, 3D isodose surfaces with patient's anatomical structures, 2D and 3D gamma index, dose volume histogram and 3D view of gamma failing points. From the analysis of 20 fiducial registrations, fiducial registration error was measured to be 0.62 mm and fiducial localization error was calculated to be 0.44 mm. Target registration uncertainty of the proposed methodology was estimated to be within 0.3 mm in the area of dose measurement. CONCLUSIONS: This study proposed a robust methodology of 3D measurement-based IMRT QA for organ-specific dose comparison and demonstrated its clinical feasibility.


Assuntos
Radioterapia de Intensidade Modulada , Algoritmos , Marcadores Fiduciais , Humanos , Radiometria , Tomografia Computadorizada por Raios X
17.
J Biomed Sci ; 27(1): 102, 2020 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-33248456

RESUMO

BACKGROUND: Esophageal squamous cell carcinoma (ESCC) is widely prevalent in Taiwan, and high metastatic spread of ESCC leads to poor survival rate. Fibronectin (FN) assembly on the cell membrane may induce ESCC mobility. MicroRNAs (MiRNAs) are abundant in and participate in tumorigenesis in many cancers. However, the role of MiRNA in FN assembly-related ESCC mobility remains unexplored. METHODS: We divided ESCC CE81T cells into high-FN assembly (CE81FN+) and low-FN assembly (CE81FN-) groups by flow cytometry. MiRNA microarray analysis identified miR-146a expression as the most down-regulated miRNA in comparison of CE81FN+ and CE81FN- cells. RESULTS: Cell proliferation and migration were decreased when CE81FN+ cells overexpressed transgenic miR-146a compared to the parental cells, indicating an inverse correlation between low miR-146a expression and high proliferation as well as motility of FN assembly ESCC cells. Furthermore, vimentin is the target gene of miR-146a involved in ESCC tumorigenesis. MiR-146a suppressed cell proliferation, migration and invasion of CE81FN+ cells through the inhibition of vimentin expression, as confirmed by real-time PCR, Western blotting and Transwell™ assay. Analysis of one hundred and thirty-six paired ESCC patient specimens revealed that low miR-146a and high vimentin levels were frequently detected in tumor, and that the former was associated with late tumor stages (III and IV). Notably, either low miR-146a expression or high vimentin level was significantly associated with poor overall survival rate among ESCC patients. CONCLUSIONS: This is the first report to link FN assembly in the cell membrane with miR-146a, vimentin and ESCC tumorigenesis both in vitro and in ESCC patients.


Assuntos
Neoplasias Esofágicas/metabolismo , Carcinoma de Células Escamosas do Esôfago/metabolismo , Fibronectinas/genética , MicroRNAs/genética , Vimentina/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Linhagem Celular Tumoral , Membrana Celular/fisiologia , Movimento Celular , Proliferação de Células , Neoplasias Esofágicas/etiologia , Carcinoma de Células Escamosas do Esôfago/etiologia , Feminino , Fibronectinas/metabolismo , Humanos , Masculino , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Vimentina/metabolismo
18.
J Org Chem ; 85(24): 16060-16071, 2020 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-33236906

RESUMO

We report a one-pot glycosylation strategy for achieving rapid syntheses of heptose (Hep)-containing oligosaccharides. The reported procedure was designed to incorporate an in situ phosphorylation step into an orthogonal one-pot glycosylation. Hep-containing oligosaccharides were assembled directly from building blocks with minimal effort expended on manipulation of protecting and aglycone leaving groups. The utility of our one-pot procedure was illustrated by synthesizing partial core oligosaccharide structure present in the lipopolysaccharide of Ralstonia solanacearum.

19.
Med Sci Monit ; 26: e922836, 2020 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-32511216

RESUMO

BACKGROUND Aberrant expression of cadherin family members and their possible biological function have been widely studied in renal cell carcinoma (RCC). However, the expression of cadherin 4 (CDH4) and its value in RCC diagnosis and prognosis remains elusive. MATERIAL AND METHODS The TCGA database was used to analyze the expression of CDH4 and its clinical parameters and prognosis in 891 RCC patients. In addition, real-time PCR was used to verify the transcription of CDH4 in renal clear cell carcinoma tissue, and the distribution of protein was observed by immunohistochemical staining. RESULTS We found that the mRNA level of CDH4 was elevated in primary RCC in contrast with normal kidney samples using bioinformatics analysis based on the TCGA database. Among the 3 main subtypes of RCC, transcriptional CDH4 was significantly increased in KIRC and KIRP, while it was downregulated in KICH. Interestingly, CDH4 mRNA gradually decreased with the progression of KIRC and KIRP. The transcription of CDH4 in the primary tumor of KIRP patients at T3-T4 stages and KIRC patients with lymph node and distant metastasis were decreased significantly. Overall survival (OS) showed that KIRC and KICH patients with lower expression of CDH4 had worse outcomes. CONCLUSIONS The transcriptional level of CDH4 may serve as an effective diagnostic and prognostic biomarker for RCC patients.


Assuntos
Caderinas/genética , Carcinoma de Células Renais/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Caderinas/metabolismo , Carcinoma de Células Renais/metabolismo , Carcinoma de Células Renais/patologia , Bases de Dados Genéticas , Progressão da Doença , Feminino , Humanos , Neoplasias Renais/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico
20.
J Appl Clin Med Phys ; 21(3): 167-177, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32100948

RESUMO

PURPOSE: A novel radiochromic PRESAGE sheet (Heuris Inc.) with 3 mm thickness has been developed as a measurement tool for 2D dosimetry. Its inherent ability to conform to irregular surfaces makes this dosimeter advantageous for patient surface dosimetry. This study is a comprehensive investigation into the PRESAGE sheet's dosimetric characteristic, accuracy and its potential use as a dosimeter for clinical applications. METHODS: The characterization of the dosimeter included evaluation of the temporal stability of the dose linearity, reproducibility, measurement uncertainties, dose rate, energy, temperature and angular dependence, lateral response artifacts, percent depth dose curve, and 2D dose measurement. Dose distribution measurements were acquired for regular square fields on a flat and irregular surface and an irregular modulated field on the smooth surface. All measurements were performed using an Epson 11000XL high-resolution scanner. RESULTS: The examined dosimeters exhibit stable linear response, standard error of repeated measurements within 2%, negligible dose rate, energy, and angular dependence. The same linear dose response was measured while the dosimeter was in contact with a heated water surface. Gamma test and histogram analysis of the dose difference between PRESAGE and EBT3 film, PRESAGE and the treatment planning system (TPS) were used to evaluate the measured dose distributions. The PRESAGE sheet dose distributions showed good agreement with EBT3 film and TPS. A discrepancy smaller than the statistical error of the two dosimeters was reported. CONCLUSIONS: This study established a full dosimetric characterization of the PRESAGE sheets with the purpose of laying the foundation for future clinical uses. The results presented here for the comparison of this novel dosimeter with those currently in use reinforce the possibility of using this dosimeter as an alternative for irregular surface dose measurements.


Assuntos
Dosimetria Fotográfica/métodos , Imagens de Fantasmas , Radiografia Torácica/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Humanos , Doses de Radiação , Radioterapia de Intensidade Modulada/métodos
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