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1.
Proc Natl Acad Sci U S A ; 117(49): 31219-31230, 2020 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-33229527

RESUMO

Type 1 diabetes (T1D) results from the autoimmune destruction of ß cells, so cure of firmly established T1D requires both reversal of autoimmunity and restoration of ß cells. It is known that ß cell regeneration in nonautoimmune diabetic mice can come from differentiation of progenitors and/or transdifferentiation of α cells. However, the source of ß cell regeneration in autoimmune nonobese diabetic (NOD) mice remains unclear. Here, we show that, after reversal of autoimmunity by induction of haploidentical mixed chimerism, administration of gastrin plus epidermal growth factor augments ß cell regeneration and normalizes blood glucose in the firmly established diabetic NOD mice. Using transgenic NOD mice with inducible lineage-tracing markers for insulin-producing ß cells, Sox9+ ductal progenitors, Nestin+ mesenchymal stem cells, and glucagon-producing α cells, we have found that both reactivation of dysfunctional low-level insulin expression (insulinlo) ß cells and neogenesis contribute to the regeneration, with the latter predominantly coming from transdifferentiation of α cells. These results indicate that, after reversal of autoimmunity, reactivation of ß cells and transdifferentiation of α cells can provide sufficient new functional ß cells to reach euglycemia in firmly established T1D.

3.
Front Oncol ; 10: 1568, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33042801

RESUMO

Objective: This study investigated survival in selected Chinese patients with advanced lung adenocarcinoma who received initial chemotherapy with pemetrexed. We also explored the relationship between genetic biomarkers and pemetrexed efficacy. Methods: We retrospectively collected patients (n = 1,047) enrolled in the Chinese Patient Assistance Program from multiple centers who received pemetrexed alone or combined with platinum as initial chemotherapy and continued pemetrexed maintenance therapy for advanced lung adenocarcinoma from November 2014 to June 2017. The outcomes were duration of treatment (DOT) and overall survival (OS). Clinical features were analyzed for their influence on the treatment effect and prognosis. Next-generation sequencing (NGS) was performed to identify genetic biomarkers associated with the efficacy of pemetrexed. Results: The median DOT was 9.1 months (95% CI: 8.5-9.8), and the median OS was 26.2 months (95% CI: 24.2-28.1). OS was positively correlated with DOT (r = 0.403, P < 0.001). Multivariable analysis showed that smoking status and Eastern Cooperative Oncology Group (ECOG) performance status (PS) were independently associated with DOT; smoking status, ECOG PS, targeted therapy, and EGFR/ALK/ROS1 status were independently associated with OS. NGS in 22 patients with available samples showed genes with high mutation rates were: TP53 (54.5%), EGFR (50.0%), MYC (18.2%), and PIK3CA (13.6%). When grouped based on progression-free survival (PFS) reported in the PARAMOUNT study, the DOT > 6.9 months set was associated with PIK3CA, ALK, BRINP3, CDKN2A, CSMD3, EPHA3, KRAS, and RB1 mutations, while ERBB2 mutation was observed only in the DOT ≤ 6.9 months set. Conclusion: This study shows that initial chemotherapy with pemetrexed is an effective regimen for advanced lung adenocarcinoma in selected Chinese patients. There is no specific genetic profile predicting the benefit of pemetrexed found by NGS. Biomarkers predicting the efficacy of pemetrexed need further exploration.

4.
J Clin Invest ; 130(12): 6457-6476, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32817590

RESUMO

Clinical trials are currently testing whether induction of haploidentical mixed chimerism (Haplo-MC) induces organ transplantation tolerance. Whether Haplo-MC can be used to treat established autoimmune diseases remains unknown. Here, we show that established autoimmunity in euthymic and adult-thymectomized NOD (H-2g7) mice was cured by induction of Haplo-MC under a non-myeloablative anti-thymocyte globulin-based conditioning regimen and infusion of CD4+ T cell-depleted hematopoietic graft from H-2b/g7 F1 donors that expressed autoimmune-resistant H-2b or from H-2s/g7 F1 donors that expressed autoimmune-susceptible H-2s. The cure was associated with enhanced thymic negative selection, increased thymic Treg (tTreg) production, and anergy or exhaustion of residual host-type autoreactive T cells in the periphery. The peripheral tolerance was accompanied by expansion of donor- and host-type CD62L-Helios+ tTregs as well as host-type Helios-Nrp1+ peripheral Tregs (pTregs) and PD-L1hi plasmacytoid DCs (pDCs). Depletion of donor- or host-type Tregs led to reduction of host-type PD-L1hi pDCs and recurrence of autoimmunity, whereas PD-L1 deficiency in host-type DCs led to reduction of host-type pDCs and Helios-Nrp1+ pTregs. Thus, induction of Haplo-MC reestablished both central and peripheral tolerance through mechanisms that depend on allo-MHC+ donor-type DCs, PD-L1hi host-type DCs, and the generation and persistence of donor- and host-type tTregs and pTregs.

5.
Pharmacoepidemiol Drug Saf ; 29(8): 958-961, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32406104

RESUMO

PURPOSE: Epidemiologic studies consistently report an increased risk of aortic aneurysm (AA) among users of fluoroquinolones (FQ), but confounding by smoking could explain all or some of the observed risk. Therefore, to better elucidate the potential causal impact of FQ on AA, we quantitatively evaluated the potential confounding effect of smoking on this observed association. METHODS: We conducted a series of quantitative bias analyses using three previously published approaches: the E-value approach, the rule-out approach, and the array approach. We additionally conducted a numerical comparison between the rule-out approach and the E-value approach. RESULTS: For an apparent relative risk of 2, the E-value is 3.41, suggesting that smoking needs to be associated with both FQ and AA with a minimal magnitude of 3.41 to explain away the observed twofold FQ-AA association. The array approach found that the prevalence of smoking among FQ users would need to be at least 2.9 times higher (43%) than the nonusers (15%), assuming smoking increases the risk of AA by 7.6-fold. A numerical comparison demonstrated that the results from the rule-out approach are similar to that of the E-value approach when there is a lack of prior data on bias parameters. CONCLUSIONS: Using three different approaches, we demonstrate that the strengths of association between smoking and both FQ and AA need to be unusually strong to fully account for the twofold increased risk between FQ and AA. Therefore, it is unlikely that smoking alone would explain away the association reported in the epidemiologic studies.

6.
J Natl Cancer Inst ; 112(10): 1003-1012, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31917448

RESUMO

BACKGROUND: Although 20 pancreatic cancer susceptibility loci have been identified through genome-wide association studies in individuals of European ancestry, much of its heritability remains unexplained and the genes responsible largely unknown. METHODS: To discover novel pancreatic cancer risk loci and possible causal genes, we performed a pancreatic cancer transcriptome-wide association study in Europeans using three approaches: FUSION, MetaXcan, and Summary-MulTiXcan. We integrated genome-wide association studies summary statistics from 9040 pancreatic cancer cases and 12 496 controls, with gene expression prediction models built using transcriptome data from histologically normal pancreatic tissue samples (NCI Laboratory of Translational Genomics [n = 95] and Genotype-Tissue Expression v7 [n = 174] datasets) and data from 48 different tissues (Genotype-Tissue Expression v7, n = 74-421 samples). RESULTS: We identified 25 genes whose genetically predicted expression was statistically significantly associated with pancreatic cancer risk (false discovery rate < .05), including 14 candidate genes at 11 novel loci (1p36.12: CELA3B; 9q31.1: SMC2, SMC2-AS1; 10q23.31: RP11-80H5.9; 12q13.13: SMUG1; 14q32.33: BTBD6; 15q23: HEXA; 15q26.1: RCCD1; 17q12: PNMT, CDK12, PGAP3; 17q22: SUPT4H1; 18q11.22: RP11-888D10.3; and 19p13.11: PGPEP1) and 11 at six known risk loci (5p15.33: TERT, CLPTM1L, ZDHHC11B; 7p14.1: INHBA; 9q34.2: ABO; 13q12.2: PDX1; 13q22.1: KLF5; and 16q23.1: WDR59, CFDP1, BCAR1, TMEM170A). The association for 12 of these genes (CELA3B, SMC2, and PNMT at novel risk loci and TERT, CLPTM1L, INHBA, ABO, PDX1, KLF5, WDR59, CFDP1, and BCAR1 at known loci) remained statistically significant after Bonferroni correction. CONCLUSIONS: By integrating gene expression and genotype data, we identified novel pancreatic cancer risk loci and candidate functional genes that warrant further investigation.

7.
Neuropsychiatr Dis Treat ; 15: 2301-2311, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31616146

RESUMO

Purpose: Nursing survivors are often not only the victims but also the rescuers in a disaster. Severe natural disasters can cause them long-term psychological impact. This study aimed to investigate the psychological status of nursing survivors and its associated factors 6 years after the severe earthquake that occurred in Wenchuan, Sichuan, on May 12, 2008. Methods: The study used a cross-sectional design. A total of 597 nurses who survived the earthquake and took care of victims were recruited about 6 years after the disaster. They completed a self-report questionnaire assessing information about demographics, earthquake-related characteristics, psychological status, posttraumatic stress disorder, and posttraumatic growth and resilience. Results: The mean score on the Symptom Checklist-90-Revised (SCL-90-R) was (123.56±41.26). Of symptoms indicated by the SCL-90-R, obsessive-compulsive dimension had the highest score (1.62±0.62). The psychological status of nursing survivors differed with the title, monthly per capita household income, financial loss, health status, residential satisfaction, and satisfaction with leaders and colleagues. Severe financial loss and poor health status were significant factors of psychological distress. In addition, psychological status was negatively related to posttraumatic stress disorder and posttraumatic growth, and positively related to resilience. Conclusion: Nursing survivors had a relatively normal level of psychological status 6 years after the 2008 Sichuan earthquake. However, psychological symptoms such as obsessive-compulsive patterns still remained. Interventions focusing on the improvement of financial subsidies and physical health may be particularly useful in reducing psychological problems after the disaster.

8.
Science ; 366(6464): 505-508, 2019 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-31649201

RESUMO

Cation-chloride cotransporters (CCCs) mediate the coupled, electroneutral symport of cations with chloride across the plasma membrane and are vital for cell volume regulation, salt reabsorption in the kidney, and γ-aminobutyric acid (GABA)-mediated modulation in neurons. Here we present cryo-electron microscopy (cryo-EM) structures of human potassium-chloride cotransporter KCC1 in potassium chloride or sodium chloride at 2.9- to 3.5-angstrom resolution. KCC1 exists as a dimer, with both extracellular and transmembrane domains involved in dimerization. The structural and functional analyses, along with computational studies, reveal one potassium site and two chloride sites in KCC1, which are all required for the ion transport activity. KCC1 adopts an inward-facing conformation, with the extracellular gate occluded. The KCC1 structures allow us to model a potential ion transport mechanism in KCCs and provide a blueprint for drug design.


Assuntos
Simportadores de Cloreto de Sódio-Potássio/química , Simportadores/química , Sequência de Aminoácidos , Animais , Sítios de Ligação , Microscopia Crioeletrônica , Células HEK293 , Humanos , Transporte de Íons , Camundongos , Simulação de Dinâmica Molecular , Oócitos , Domínios Proteicos , Multimerização Proteica , Estrutura Quaternária de Proteína , Alinhamento de Sequência , Xenopus laevis
9.
Cancer Epidemiol Biomarkers Prev ; 28(11): 1868-1875, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31427306

RESUMO

BACKGROUND: Leukocyte telomere length has been associated with risk of subsequent pancreatic cancer. Few prospective studies have evaluated the association of prediagnostic leukocyte telomere length with pancreatic cancer survival. METHODS: We prospectively examined the association of prediagnostic leukocyte telomere length with overall survival (OS) time among 423 participants diagnosed with pancreatic adenocarcinoma between 1984 and 2008 within the Health Professionals Follow-up Study, Nurses' Health Study, Physicians' Health Study, and Women's Health Initiative. We measured prediagnostic leukocyte telomere length in banked blood samples using quantitative PCR. Cox proportional hazards models were used to estimate HRs for OS with adjustment for potential confounders. We also evaluated 10 SNPs at the telomerase reverse transcriptase locus. RESULTS: Shorter prediagnostic leukocyte telomere length was associated with reduced OS among patients with pancreatic cancer (P trend = 0.04). The multivariable-adjusted HR for OS comparing the lowest with highest quintiles of leukocyte telomere length was 1.39 (95% confidence interval, 1.01-1.93), corresponding to a 3-month difference in median OS time. In an analysis excluding cases with blood collected within 2 years of cancer diagnosis, the association was moderately stronger (HR, 1.55; 95% confidence interval, 1.09-2.21; comparing the lowest with highest quintiles; P trend = 0.01). No prognostic association or effect modification for the prognostic association of prediagnostic leukocyte telomere length was noted in relation to the studied SNPs. CONCLUSIONS: Prediagnostic leukocyte telomere length was associated with pancreatic cancer survival. IMPACT: Prediagnostic leukocyte telomere length can be a prognostic biomarker in pancreatic cancer.


Assuntos
Leucócitos/metabolismo , Neoplasias Pancreáticas/fisiopatologia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/mortalidade , Estudos Prospectivos , Fatores de Risco , Análise de Sobrevida , Telômero/patologia
10.
Biochem Biophys Res Commun ; 514(4): 1133-1139, 2019 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-31101341

RESUMO

Ultraviolet B (UVB) irradiation increases the risk of various skin disorders, resulting in apoptosis, autophagy and oxidative stress and thereby promoting the risk of skin photoaging and carcinogenesis. The use of photochemoprotectors including natural products with antioxidant properties represents an effective strategy for preventing UVB-induced skin injury. Isoorientin (Iso), as a flavonoid compound, could be extracted from several plant species and possesses multiple biological activities. However, its role in regulating UVB-induced skin damage is little to be reported. In the study, we found that Iso treatment could protect human dermal fibroblasts (HDFs) against the effects of UVB irradiation by improving cell viability, suppressing MMP1 and MMP3 expression, inhibiting oxidative stress and inducing autophagy. In addition, Iso reduced UVB-triggered apoptosis, as evidenced by the decreased Caspase-3 activity in vitro. Furthermore, Iso was functioned as reactive oxygen species (ROS) scavenger that markedly hindered c-Jun N-terminal kinases (JNK) signaling activation in UVB-treated HFDs. Importantly, promoting JNK activity restored matrix metalloproteinase (MMP)-1/3 expression in Iso-incubated cells with UVB stimulation. Meanwhile, UVB exposure to the skin of mice and subsequent topical application of Iso delayed the progression of skin damage, resulting in autophagy and blocking the JNK activation and ROS production. In conclusion, these results indicated the photoprotective role of Iso and demonstrated that Iso could also be potentially used as an agent against UVB-stimulated skin damage.


Assuntos
Apoptose/efeitos dos fármacos , Luteolina/farmacologia , Mitocôndrias/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Espécies Reativas de Oxigênio/antagonistas & inibidores , Pele/efeitos dos fármacos , Raios Ultravioleta , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Processos Fotoquímicos , Espécies Reativas de Oxigênio/metabolismo , Pele/lesões , Pele/metabolismo
11.
Biochem Biophys Res Commun ; 513(2): 419-425, 2019 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-30967266

RESUMO

Cutaneous squamous cell carcinoma (CSCC) remains the second most prevailing cancer worldwide and presents high mortality rates. Given that chemoresistance becomes an enormous obstacle to the therapy for CSCC patients, there is a pressing need to discover novel strategies for enhancing the response of CSCC cells to cisplatin. Emerging evidence has unfolded that miRNAs are participated in regulation of drug resistance in multiple cancers. MiR-3619-5p has been proofed to exert tumor inhibitive activities in human malignancies, but the biological function of miR-3619-5p in the progression of CSCC is still unclear. In this study, we observed that miR-3619-5p expression was pronouncedly dropped in cisplatin-resistant CSCC cells. Subsequently, miR-3619-5p was validated to act as a tumor suppressor in CSCC through retarding cell proliferation and cisplatin resistance. Besides, our findings certified that KPNA4 was highly expressed in cisplatin-resistant CSCC cells. Further, KPNA4 was negatively regulated by miR-3619-5p. Rescue experiments unveiled that KPNA4 counteracted the miR-3619-5p-mediated regulation of CSCC tumorigenesis. On the whole, miR-3619-5p inhibited cell proliferation and cisplatin resistance of CSCC by regulating KPNA4 expression, suggesting that miR-3619-5p/KPNA4 pathway may represent a potential promising strategy for the treatment of patients with CSCC.


Assuntos
Antineoplásicos/farmacologia , Carcinoma de Células Escamosas/genética , Cisplatino/farmacologia , MicroRNAs/genética , Neoplasias Cutâneas/genética , alfa Carioferinas/genética , Carcinoma de Células Escamosas/tratamento farmacológico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Neoplasias Cutâneas/tratamento farmacológico
12.
J Natl Cancer Inst ; 111(6): 557-567, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30541042

RESUMO

BACKGROUND: Genome-wide association studies (GWAS) identify associations of individual single-nucleotide polymorphisms (SNPs) with cancer risk but usually only explain a fraction of the inherited variability. Pathway analysis of genetic variants is a powerful tool to identify networks of susceptibility genes. METHODS: We conducted a large agnostic pathway-based meta-analysis of GWAS data using the summary-based adaptive rank truncated product method to identify gene sets and pathways associated with pancreatic ductal adenocarcinoma (PDAC) in 9040 cases and 12 496 controls. We performed expression quantitative trait loci (eQTL) analysis and functional annotation of the top SNPs in genes contributing to the top associated pathways and gene sets. All statistical tests were two-sided. RESULTS: We identified 14 pathways and gene sets associated with PDAC at a false discovery rate of less than 0.05. After Bonferroni correction (P ≤ 1.3 × 10-5), the strongest associations were detected in five pathways and gene sets, including maturity-onset diabetes of the young, regulation of beta-cell development, role of epidermal growth factor (EGF) receptor transactivation by G protein-coupled receptors in cardiac hypertrophy pathways, and the Nikolsky breast cancer chr17q11-q21 amplicon and Pujana ATM Pearson correlation coefficient (PCC) network gene sets. We identified and validated rs876493 and three correlating SNPs (PGAP3) and rs3124737 (CASP7) from the Pujana ATM PCC gene set as eQTLs in two normal derived pancreas tissue datasets. CONCLUSION: Our agnostic pathway and gene set analysis integrated with functional annotation and eQTL analysis provides insight into genes and pathways that may be biologically relevant for risk of PDAC, including those not previously identified.


Assuntos
Carcinoma Ductal Pancreático/genética , Estudo de Associação Genômica Ampla/métodos , Neoplasias Pancreáticas/genética , Estudos de Casos e Controles , Predisposição Genética para Doença , Humanos , Modelos Estatísticos , Polimorfismo de Nucleotídeo Único
13.
Nat Struct Mol Biol ; 25(9): 850-858, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30190597

RESUMO

Mechanosensitive ion channels convert mechanical stimuli into a flow of ions. These channels are widely distributed from bacteria to higher plants and humans, and are involved in many crucial physiological processes. Here we show that two members of the OSCA protein family in Arabidopsis thaliana, namely AtOSCA1.1 and AtOSCA3.1, belong to a new class of mechanosensitive ion channels. We solve the structure of the AtOSCA1.1 channel at 3.5-Å resolution and AtOSCA3.1 at 4.8-Å resolution by cryo-electron microscopy. OSCA channels are symmetric dimers that are mediated by cytosolic inter-subunit interactions. Strikingly, they have structural similarity to the mammalian TMEM16 family proteins. Our structural analysis accompanied with electrophysiological studies identifies the ion permeation pathway within each subunit and suggests a conformational change model for activation.


Assuntos
Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/fisiologia , Canais Iônicos/química , Canais Iônicos/fisiologia , Mecanotransdução Celular , Animais , Microscopia Crioeletrônica , Citoplasma/química , Dimerização , Humanos
14.
Thorac Cancer ; 9(7): 814-819, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29722148

RESUMO

BACKGROUND: EGFR-tyrosine kinase inhibitors play an important role in the treatment of advanced non-small cell lung cancer (NSCLC). EGFR mutations in advanced NSCLC occur in approximately 35% of Asian patients and 60% of patients with adenocarcinoma. However, the frequency and type of EGFR mutations in early-stage lung adenocarcinoma remain unclear. METHODS: We retrospectively collected data on patients diagnosed with lung adenocarcinoma tested for EGFR mutation. Early stage was defined as pathological stage IA-IIIA after radical lung cancer surgery, and advanced stage was defined as clinical stage IIIB without the opportunity for curative treatment or stage IV according to the American Joint Committee on Cancer Staging Manual, 7th edition. RESULTS: A total of 1699 patients were enrolled in this study from May 2014 to May 2016; 750 were assigned to the early-stage and 949 to the advanced-stage group. Baseline characteristics of the two groups were balanced, except that there were more smokers in the advanced-stage group (P < 0.001). The total EGFR mutation rate in the early-stage group was similar to that in the advanced-stage group (53.6% vs. 51.4%, respectively; P = 0.379). There was no significant difference in EGFR mutation type between the two groups. In subgroup analysis of smoking history, there was no difference in EGFR mutation frequency or type between the early-stage and advanced-stage groups. CONCLUSION: Early-stage and advanced-stage groups exhibited the same EGFR mutation frequencies and types.


Assuntos
Adenocarcinoma de Pulmão/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Adenocarcinoma de Pulmão/epidemiologia , Adenocarcinoma de Pulmão/patologia , Idoso , Grupo com Ancestrais do Continente Asiático , Carcinoma Pulmonar de Células não Pequenas/epidemiologia , Carcinoma Pulmonar de Células não Pequenas/patologia , China/epidemiologia , Receptores ErbB/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Estadiamento de Neoplasias , Inibidores de Proteínas Quinases/uso terapêutico , Estudos Retrospectivos , Fumar/efeitos adversos
15.
Cell Rep ; 23(1): 23-31, 2018 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-29617663

RESUMO

How we sense touch is fundamental for many physiological processes. However, the underlying mechanism and molecular identity for touch sensation are largely unknown. Here, we report on defective gentle-touch behavioral responses in brv1 loss-of-function Drosophila larvae. RNAi and Ca2+ imaging confirmed the involvement of Brv1 in sensing touch and demonstrated that Brv1 mediates the mechanotransduction of class III dendritic arborization neurons. Electrophysiological recordings further revealed that the expression of Brv1 protein in HEK293T cells gives rise to stretch-activated cation channels. Purified Brv1 protein reconstituted into liposomes were found to sense stretch stimuli. In addition, co-expression studies suggested that Brv1 amplifies the response of mechanosensitive ion channel NOMPC (no mechanoreceptor potential C) to touch stimuli. Altogether, these findings demonstrate a molecular entity that mediates the gentle-touch response in Drosophila larvae, providing insights into the molecular mechanisms of touch sensation.


Assuntos
Proteínas de Drosophila/metabolismo , Mecanotransdução Celular , Tato , Canais de Receptores Transientes de Potencial/metabolismo , Potenciais de Ação , Animais , Proteínas de Drosophila/genética , Drosophila melanogaster , Células Receptoras Sensoriais/fisiologia , Canais de Receptores Transientes de Potencial/genética
17.
Nat Commun ; 9(1): 556, 2018 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-29422604

RESUMO

In 2020, 146,063 deaths due to pancreatic cancer are estimated to occur in Europe and the United States combined. To identify common susceptibility alleles, we performed the largest pancreatic cancer GWAS to date, including 9040 patients and 12,496 controls of European ancestry from the Pancreatic Cancer Cohort Consortium (PanScan) and the Pancreatic Cancer Case-Control Consortium (PanC4). Here, we find significant evidence of a novel association at rs78417682 (7p12/TNS3, P = 4.35 × 10-8). Replication of 10 promising signals in up to 2737 patients and 4752 controls from the PANcreatic Disease ReseArch (PANDoRA) consortium yields new genome-wide significant loci: rs13303010 at 1p36.33 (NOC2L, P = 8.36 × 10-14), rs2941471 at 8q21.11 (HNF4G, P = 6.60 × 10-10), rs4795218 at 17q12 (HNF1B, P = 1.32 × 10-8), and rs1517037 at 18q21.32 (GRP, P = 3.28 × 10-8). rs78417682 is not statistically significantly associated with pancreatic cancer in PANDoRA. Expression quantitative trait locus analysis in three independent pancreatic data sets provides molecular support of NOC2L as a pancreatic cancer susceptibility gene.


Assuntos
Carcinoma Ductal Pancreático/genética , Neoplasias Pancreáticas/genética , Bases de Dados Genéticas , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Fator 1-beta Nuclear de Hepatócito/genética , Fator 4 Nuclear de Hepatócito/genética , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Polimorfismo de Nucleotídeo Único , Proteínas/genética , Proteínas Repressoras/genética , Tensinas/genética
18.
Nature ; 554(7693): 533-537, 2018 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-29443959

RESUMO

Chronic inflammation increases the risk of developing one of several types of cancer. Inflammatory responses are currently thought to be controlled by mechanisms that rely on transcriptional networks that are distinct from those involved in cell differentiation. The orphan nuclear receptor NR5A2 participates in a wide variety of processes, including cholesterol and glucose metabolism in the liver, resolution of endoplasmic reticulum stress, intestinal glucocorticoid production, pancreatic development and acinar differentiation. In genome-wide association studies, single nucleotide polymorphisms in the vicinity of NR5A2 have previously been associated with the risk of pancreatic adenocarcinoma. In mice, Nr5a2 heterozygosity sensitizes the pancreas to damage, impairs regeneration and cooperates with mutant Kras in tumour progression. Here, using a global transcriptomic analysis, we describe an epithelial-cell-autonomous basal pre-inflammatory state in the pancreas of Nr5a2+/- mice that is reminiscent of the early stages of pancreatitis-induced inflammation and is conserved in histologically normal human pancreases with reduced expression of NR5A2 mRNA. In Nr5a2+/-mice, NR5A2 undergoes a marked transcriptional switch, relocating from differentiation-specific to inflammatory genes and thereby promoting gene transcription that is dependent on the AP-1 transcription factor. Pancreatic deletion of Jun rescues the pre-inflammatory phenotype, as well as binding of NR5A2 to inflammatory gene promoters and the defective regenerative response to damage. These findings support the notion that, in the pancreas, the transcriptional networks involved in differentiation-specific functions also suppress inflammatory programmes. Under conditions of genetic or environmental constraint, these networks can be subverted to foster inflammation.


Assuntos
Diferenciação Celular/genética , Regulação da Expressão Gênica , Inflamação/genética , Pâncreas/metabolismo , Pâncreas/patologia , Receptores Citoplasmáticos e Nucleares/metabolismo , Transcriptoma , Células Acinares/metabolismo , Células Acinares/patologia , Animais , Cromatina/genética , Cromatina/metabolismo , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Redes Reguladoras de Genes/genética , Genes jun/genética , Heterozigoto , Humanos , Camundongos , Especificidade de Órgãos/genética , Pancreatite/genética , Regiões Promotoras Genéticas/genética , Receptores Citoplasmáticos e Nucleares/deficiência , Receptores Citoplasmáticos e Nucleares/genética , Fator de Transcrição AP-1/metabolismo
19.
Proc Natl Acad Sci U S A ; 115(10): E2329-E2337, 2018 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-29463744

RESUMO

Autoimmune type 1 diabetes (T1D) and other autoimmune diseases are associated with particular MHC haplotypes and expansion of autoreactive T cells. Induction of MHC-mismatched but not -matched mixed chimerism by hematopoietic cell transplantation effectively reverses autoimmunity in diabetic nonobese diabetic (NOD) mice, even those with established diabetes. As expected, MHC-mismatched mixed chimerism mediates deletion in the thymus of host-type autoreactive T cells that have T-cell receptor (TCR) recognizing (cross-reacting with) donor-type antigen presenting cells (APCs), which have come to reside in the thymus. However, how MHC-mismatched mixed chimerism tolerizes host autoreactive T cells that recognize only self-MHC-peptide complexes remains unknown. Here, using NOD.Rag1-/-BDC2.5 or NOD.Rag1-/-BDC12-4.1 mice that have only noncross-reactive transgenic autoreactive T cells, we show that induction of MHC-mismatched but not -matched mixed chimerism restores immune tolerance of peripheral noncross-reactive autoreactive T cells. MHC-mismatched mixed chimerism results in increased percentages of both donor- and host-type Foxp3+ Treg cells and up-regulated expression of programmed death-ligand 1 (PD-L1) by host-type plasmacytoid dendritic cells (pDCs). Furthermore, adoptive transfer experiments showed that engraftment of donor-type dendritic cells (DCs) and expansion of donor-type Treg cells are required for tolerizing the noncross-reactive autoreactive T cells in the periphery, which are in association with up-regulation of host-type DC expression of PD-L1 and increased percentage of host-type Treg cells. Thus, induction of MHC-mismatched mixed chimerism may establish a peripheral tolerogenic DC and Treg network that actively tolerizes autoreactive T cells, even those with no TCR recognition of the donor APCs.


Assuntos
Diabetes Mellitus Tipo 1/genética , Complexo Principal de Histocompatibilidade , Tolerância Periférica , Linfócitos T/imunologia , Animais , Autoimunidade , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/terapia , Feminino , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/imunologia , Linfócitos T/transplante , Quimeras de Transplante/genética
20.
Gut ; 67(3): 521-533, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28634199

RESUMO

OBJECTIVE: To elucidate the genetic architecture of gene expression in pancreatic tissues. DESIGN: We performed expression quantitative trait locus (eQTL) analysis in histologically normal pancreatic tissue samples (n=95) using RNA sequencing and the corresponding 1000 genomes imputed germline genotypes. Data from pancreatic tumour-derived tissue samples (n=115) from The Cancer Genome Atlas were included for comparison. RESULTS: We identified 38 615 cis-eQTLs (in 484 genes) in histologically normal tissues and 39 713 cis-eQTL (in 237 genes) in tumour-derived tissues (false discovery rate <0.1), with the strongest effects seen near transcriptional start sites. Approximately 23% and 42% of genes with significant cis-eQTLs appeared to be specific for tumour-derived and normal-derived tissues, respectively. Significant enrichment of cis-eQTL variants was noted in non-coding regulatory regions, in particular for pancreatic tissues (1.53-fold to 3.12-fold, p≤0.0001), indicating tissue-specific functional relevance. A common pancreatic cancer risk locus on 9q34.2 (rs687289) was associated with ABO expression in histologically normal (p=5.8×10-8) and tumour-derived (p=8.3×10-5) tissues. The high linkage disequilibrium between this variant and the O blood group generating deletion variant in ABO (exon 6) suggested that nonsense-mediated decay (NMD) of the 'O' mRNA might explain this finding. However, knockdown of crucial NMD regulators did not influence decay of the ABO 'O' mRNA, indicating that a gene regulatory element influenced by pancreatic cancer risk alleles may underlie the eQTL. CONCLUSIONS: We have identified cis-eQTLs representing potential functional regulatory variants in the pancreas and generated a rich data set for further studies on gene expression and its regulation in pancreatic tissues.


Assuntos
Sistema ABO de Grupos Sanguíneos/genética , Expressão Gênica , Pâncreas , Neoplasias Pancreáticas/genética , Locos de Características Quantitativas , RNA Neoplásico/análise , Transcriptoma , Alelos , Cromossomos Humanos Par 9 , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Degradação do RNAm Mediada por Códon sem Sentido , Polimorfismo de Nucleotídeo Único , Sequências Reguladoras de Ácido Nucleico , Análise de Sequência de RNA
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