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1.
Nat Commun ; 15(1): 5827, 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38992008

RESUMEN

The liver has the remarkable capacity to regenerate. In the clinic, regeneration is induced by portal vein embolization, which redirects portal blood flow, resulting in liver hypertrophy in locations with increased blood supply, and atrophy of embolized segments. Here, we apply single-cell and single-nucleus transcriptomics on healthy, hypertrophied, and atrophied patient-derived liver samples to explore cell states in the regenerating liver. Our data unveils pervasive upregulation of genes associated with developmental processes, cellular adhesion, and inflammation in post-portal vein embolization liver, disrupted portal-central hepatocyte zonation, and altered cell subtype composition of endothelial and immune cells. Interlineage crosstalk analysis reveals mesenchymal cells as an interaction hub between immune and endothelial cells, and highlights the importance of extracellular matrix proteins in liver regeneration. Moreover, we establish tissue-scale iterative indirect immunofluorescence imaging for high-dimensional spatial analysis of perivascular microenvironments, uncovering changes to tissue architecture in regenerating liver lobules. Altogether, our data is a rich resource revealing cellular and histological changes in human liver regeneration.


Asunto(s)
Embolización Terapéutica , Regeneración Hepática , Hígado , Vena Porta , Humanos , Regeneración Hepática/fisiología , Embolización Terapéutica/métodos , Hepatocitos/metabolismo , Análisis de la Célula Individual , Transcriptoma , Masculino , Células Endoteliales/metabolismo , Femenino , Hipertrofia , Persona de Mediana Edad
2.
EMBO Rep ; 24(9): e57181, 2023 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-37522754

RESUMEN

Hepatocytes form bile canaliculi that dynamically respond to the signalling activity of bile acids and bile flow. Little is known about their responses to intraluminal pressure. During embryonic development, hepatocytes assemble apical bulkheads that increase the canalicular resistance to intraluminal pressure. Here, we investigate whether they also protect bile canaliculi against elevated pressure upon impaired bile flow in adult liver. Apical bulkheads accumulate upon bile flow obstruction in mouse models and patients with primary sclerosing cholangitis (PSC). Their loss under these conditions leads to abnormally dilated canaliculi, resembling liver cell rosettes described in other hepatic diseases. 3D reconstruction reveals that these structures are sections of cysts and tubes formed by hepatocytes. Mathematical modelling establishes that they positively correlate with canalicular pressure and occur in early PSC stages. Using primary hepatocytes and 3D organoids, we demonstrate that excessive canalicular pressure causes the loss of apical bulkheads and formation of rosettes. Our results suggest that apical bulkheads are a protective mechanism of hepatocytes against impaired bile flow, highlighting the role of canalicular pressure in liver diseases.


Asunto(s)
Bilis , Hepatopatías , Ratones , Animales , Hígado , Canalículos Biliares , Hepatocitos
3.
Gut ; 72(2): 381-391, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-35788059

RESUMEN

OBJECTIVE: Hepatocellular carcinoma (HCC) often develops in patients with alcohol-related cirrhosis at an annual risk of up to 2.5%. Some host genetic risk factors have been identified but do not account for the majority of the variance in occurrence. This study aimed to identify novel susceptibility loci for the development of HCC in people with alcohol related cirrhosis. DESIGN: Patients with alcohol-related cirrhosis and HCC (cases: n=1214) and controls without HCC (n=1866), recruited from Germany, Austria, Switzerland, Italy and the UK, were included in a two-stage genome-wide association study using a case-control design. A validation cohort of 1520 people misusing alcohol but with no evidence of liver disease was included to control for possible association effects with alcohol misuse. Genotyping was performed using the InfiniumGlobal Screening Array (V.24v2, Illumina) and the OmniExpress Array (V.24v1-0a, Illumina). RESULTS: Associations with variants rs738409 in PNPLA3 and rs58542926 in TM6SF2 previously associated with an increased risk of HCC in patients with alcohol-related cirrhosis were confirmed at genome-wide significance. A novel locus rs2242652(A) in TERT (telomerase reverse transcriptase) was also associated with a decreased risk of HCC, in the combined meta-analysis, at genome-wide significance (p=6.41×10-9, OR=0.61 (95% CI 0.52 to 0.70). This protective association remained significant after correction for sex, age, body mass index and type 2 diabetes (p=7.94×10-5, OR=0.63 (95% CI 0.50 to 0.79). Carriage of rs2242652(A) in TERT was associated with an increased leucocyte telomere length (p=2.12×10-44). CONCLUSION: This study identifies rs2242652 in TERT as a novel protective factor for HCC in patients with alcohol-related cirrhosis.


Asunto(s)
Carcinoma Hepatocelular , Predisposición Genética a la Enfermedad , Cirrosis Hepática Alcohólica , Neoplasias Hepáticas , Telomerasa , Humanos , Carcinoma Hepatocelular/etiología , Carcinoma Hepatocelular/genética , Estudios de Casos y Controles , Diabetes Mellitus Tipo 2/complicaciones , Variación Genética , Estudio de Asociación del Genoma Completo , Cirrosis Hepática Alcohólica/complicaciones , Cirrosis Hepática Alcohólica/genética , Neoplasias Hepáticas/etiología , Neoplasias Hepáticas/genética , Polimorfismo de Nucleótido Simple , Factores de Riesgo , Telomerasa/genética
4.
Cells ; 11(21)2022 11 04.
Artículo en Inglés | MEDLINE | ID: mdl-36359900

RESUMEN

Obesity and obesity-associated diseases represent one of the key health challenges of our time. In this context, aberrant hepatic lipid accumulation is a central pathological aspect of non-alcoholic fatty liver disease (NAFLD). By comparing methylation signatures of liver biopsies before and after bariatric surgery, we recently demonstrated the strong enrichment of differentially methylated heat shock factor 1 (HSF1) binding sites (>400-fold) in the process of liver remodeling, indicating a crucial role of HSF1 in modulating central aspects of NAFLD pathogenesis. Using cellular models of NAFLD, we were able to show that HSF1 is activated during fat accumulation in hepatocytes, mimicking conditions in patients before bariatric surgery. This induction was abolished by starving the cells, mimicking the situation after bariatric surgery. Regarding this connection, carnitine palmitoyltransferase 1 isoform A (CTP1a), a central regulator of lipid beta-oxidation, was identified as a HSF1 target gene by promoter analysis and HSF1 knockdown experiments. Finally, pharmacological activation of HSF1 through celastrol reduced fat accumulation in the cells in a HSF1-dependent manner. In conclusion, we were able to confirm the relevance of HSF1 activity and described a functional HSF1-CPT1a pathway in NAFLD pathogenesis.


Asunto(s)
Enfermedad del Hígado Graso no Alcohólico , Humanos , Enfermedad del Hígado Graso no Alcohólico/patología , Metabolismo de los Lípidos/genética , Obesidad/metabolismo , Lípidos
5.
Immunity ; 55(4): 701-717.e7, 2022 04 12.
Artículo en Inglés | MEDLINE | ID: mdl-35364006

RESUMEN

Bacterial sensing by intestinal tumor cells contributes to tumor growth through cell-intrinsic activation of the calcineurin-NFAT axis, but the role of this pathway in other intestinal cells remains unclear. Here, we found that myeloid-specific deletion of calcineurin in mice activated protective CD8+ T cell responses and inhibited colorectal cancer (CRC) growth. Microbial sensing by myeloid cells promoted calcineurin- and NFAT-dependent interleukin 6 (IL-6) release, expression of the co-inhibitory molecules B7H3 and B7H4 by tumor cells, and inhibition of CD8+ T cell-dependent anti-tumor immunity. Accordingly, targeting members of this pathway activated protective CD8+ T cell responses and inhibited primary and metastatic CRC growth. B7H3 and B7H4 were expressed by the majority of human primary CRCs and metastases, which was associated with low numbers of tumor-infiltrating CD8+ T cells and poor survival. Therefore, a microbiota-, calcineurin-, and B7H3/B7H4-dependent pathway controls anti-tumor immunity, revealing additional targets for immune checkpoint inhibition in microsatellite-stable CRC.


Asunto(s)
Neoplasias Colorrectales , Microbiota , Animales , Antígenos B7 , Linfocitos T CD8-positivos , Calcineurina/metabolismo , Neoplasias Colorrectales/metabolismo , Ratones , Factores de Transcripción NFATC/metabolismo , Inhibidor 1 de la Activación de Células T con Dominio V-Set
6.
J Lipid Res ; 62: 100104, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34384788

RESUMEN

Nonalcoholic fatty liver disease (NAFLD) is a common metabolic dysfunction leading to hepatic steatosis. However, NAFLD's global impact on the liver lipidome is poorly understood. Using high-resolution shotgun mass spectrometry, we quantified the molar abundance of 316 species from 22 major lipid classes in liver biopsies of 365 patients, including nonsteatotic patients with normal or excessive weight, patients diagnosed with NAFL (nonalcoholic fatty liver) or NASH (nonalcoholic steatohepatitis), and patients bearing common mutations of NAFLD-related protein factors. We confirmed the progressive accumulation of di- and triacylglycerols and cholesteryl esters in the liver of NAFL and NASH patients, while the bulk composition of glycerophospho- and sphingolipids remained unchanged. Further stratification by biclustering analysis identified sphingomyelin species comprising n24:2 fatty acid moieties as membrane lipid markers of NAFLD. Normalized relative abundance of sphingomyelins SM 43:3;2 and SM 43:1;2 containing n24:2 and n24:0 fatty acid moieties, respectively, showed opposite trends during NAFLD progression and distinguished NAFL and NASH lipidomes from the lipidome of nonsteatotic livers. Together with several glycerophospholipids containing a C22:6 fatty acid moiety, these lipids serve as markers of early and advanced stages of NAFL.


Asunto(s)
Lipidómica , Hígado/metabolismo , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Metabolismo de los Lípidos , Masculino , Persona de Mediana Edad , Adulto Joven
7.
Arch Toxicol ; 95(9): 3001-3013, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34241659

RESUMEN

The liver is one of the most sexually dimorphic organs. The hepatic metabolic pathways that are subject to sexual dimorphism include xenobiotic, amino acid and lipid metabolism. Non-alcoholic fatty liver disease and hepatocellular carcinoma are among diseases with sex-dependent prevalence, progression and outcome. Although male and female livers differ in their abilities to metabolize foreign compounds, including drugs, sex-dependent treatment and pharmacological dynamics are rarely applied in all relevant cases. Therefore, it is important to consider hepatic sexual dimorphism when developing new treatment strategies and to understand the underlying mechanisms in model systems. We isolated primary hepatocytes from male and female C57BL6/N mice and examined the sex-dependent transcriptome, proteome and extracellular metabolome parameters in the course of culturing them for 96 h. The sex-specific gene expression of the general xenobiotic pathway altered and the female-specific expression of Cyp2b13 and Cyp2b9 was significantly reduced during culture. Sex-dependent differences of several signaling pathways increased, including genes related to serotonin and melatonin degradation. Furthermore, the ratios of male and female gene expression were inversed for other pathways, such as amino acid degradation, beta-oxidation, androgen signaling and hepatic steatosis. Because the primary hepatocytes were cultivated without the influence of known regulators of sexual dimorphism, these results suggest currently unknown modulatory mechanisms of sexual dimorphism in vitro. The large sex-dependent differences in the regulation and dynamics of drug metabolism observed during cultivation can have an immense influence on the evaluation of pharmacodynamic processes when conducting initial preclinical trials to investigate potential new drugs.


Asunto(s)
Hepatocitos/metabolismo , Metaboloma/fisiología , Proteoma/fisiología , Transcriptoma/fisiología , Animales , Hidrocarburo de Aril Hidroxilasas/genética , Sistema Enzimático del Citocromo P-450/genética , Familia 2 del Citocromo P450/genética , Femenino , Regulación de la Expresión Génica/fisiología , Masculino , Melatonina/metabolismo , Ratones , Ratones Endogámicos C57BL , Serotonina/metabolismo , Caracteres Sexuales , Factores Sexuales , Transducción de Señal/fisiología , Esteroide Hidroxilasas/genética
8.
Gut ; 70(3): 485-498, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-32503845

RESUMEN

OBJECTIVE: The intestinal epithelium is a rapidly renewing tissue which plays central roles in nutrient uptake, barrier function and the prevention of intestinal inflammation. Control of epithelial differentiation is essential to these processes and is dependent on cell type-specific activity of transcription factors which bind to accessible chromatin. Here, we studied the role of SET Domain Bifurcated Histone Lysine Methyltransferase 1, also known as ESET (SETDB1), a histone H3K9 methyltransferase, in intestinal epithelial homeostasis and IBD. DESIGN: We investigated mice with constitutive and inducible intestinal epithelial deletion of Setdb1, studied the expression of SETDB1 in patients with IBD and mouse models of IBD, and investigated the abundance of SETDB1 variants in healthy individuals and patients with IBD. RESULTS: Deletion of intestinal epithelial Setdb1 in mice was associated with defects in intestinal epithelial differentiation, barrier disruption, inflammation and mortality. Mechanistic studies showed that loss of SETDB1 leads to de-silencing of endogenous retroviruses, DNA damage and intestinal epithelial cell death. Predicted loss-of-function variants in human SETDB1 were considerably less frequently observed than expected, consistent with a critical role of SETDB1 in human biology. While the vast majority of patients with IBD showed unimpaired mucosal SETDB1 expression, comparison of IBD and non-IBD exomes revealed over-representation of individual rare missense variants in SETDB1 in IBD, some of which are predicted to be associated with loss of function and may contribute to the pathogenesis of intestinal inflammation. CONCLUSION: SETDB1 plays an essential role in intestinal epithelial homeostasis. Future work is required to investigate whether rare variants in SETDB1 contribute to the pathogenesis of IBD.


Asunto(s)
N-Metiltransferasa de Histona-Lisina/genética , Enfermedades Inflamatorias del Intestino/genética , Mucosa Intestinal/metabolismo , Animales , Diferenciación Celular , Células Epiteliales/metabolismo , Femenino , Silenciador del Gen , Homeostasis/genética , Humanos , Mutación con Pérdida de Función , Masculino , Ratones
9.
Gut ; 70(5): 940-950, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-32591434

RESUMEN

OBJECTIVE: The rs641738C>T variant located near the membrane-bound O-acyltransferase domain containing 7 (MBOAT7) locus is associated with fibrosis in liver diseases, including non-alcoholic fatty liver disease (NAFLD), alcohol-related liver disease, hepatitis B and C. We aim to understand the mechanism by which the rs641738C>T variant contributes to pathogenesis of NAFLD. DESIGN: Mice with hepatocyte-specific deletion of MBOAT7 (Mboat7Δhep) were generated and livers were characterised by histology, flow cytometry, qPCR, RNA sequencing and lipidomics. We analysed the association of rs641738C>T genotype with liver inflammation and fibrosis in 846 NAFLD patients and obtained genotype-specific liver lipidomes from 280 human biopsies. RESULTS: Allelic imbalance analysis of heterozygous human liver samples pointed to lower expression of the MBOAT7 transcript on the rs641738C>T haplotype. Mboat7Δhep mice showed spontaneous steatosis characterised by increased hepatic cholesterol ester content after 10 weeks. After 6 weeks on a high fat, methionine-low, choline-deficient diet, mice developed increased hepatic fibrosis as measured by picrosirius staining (p<0.05), hydroxyproline content (p<0.05) and transcriptomics, while the inflammatory cell populations and inflammatory mediators were minimally affected. In a human biopsied NAFLD cohort, MBOAT7 rs641738C>T was associated with fibrosis (p=0.004) independent of the presence of histological inflammation. Liver lipidomes of Mboat7Δhep mice and human rs641738TT carriers with fibrosis showed increased total lysophosphatidylinositol levels. The altered lysophosphatidylinositol and phosphatidylinositol subspecies in MBOAT7Δhep livers and human rs641738TT carriers were similar. CONCLUSION: Mboat7 deficiency in mice and human points to an inflammation-independent pathway of liver fibrosis that may be mediated by lipid signalling and a potentially targetable treatment option in NAFLD.


Asunto(s)
Aciltransferasas/genética , Cirrosis Hepática/genética , Proteínas de la Membrana/genética , Enfermedad del Hígado Graso no Alcohólico/genética , Aciltransferasas/deficiencia , Adulto , Anciano , Animales , Biopsia , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Femenino , Genotipo , Haplotipos , Humanos , Inflamación/genética , Masculino , Proteínas de la Membrana/deficiencia , Ratones Endogámicos C57BL , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple
10.
Gastroenterology ; 159(4): 1276-1289.e7, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32561361

RESUMEN

BACKGROUND AND AIMS: Little is known about genetic factors that affect development of alcohol-related cirrhosis. We performed a genome-wide association study (GWAS) of samples from the United Kingdom Biobank (UKB) to identify polymorphisms associated with risk of alcohol-related liver disease. METHODS: We performed a GWAS of 35,839 participants in the UKB with high intake of alcohol against markers of hepatic fibrosis (FIB-4, APRI, and Forns index scores) and hepatocellular injury (levels of aminotransferases). Loci identified in the discovery analysis were tested for their association with alcohol-related cirrhosis in 3 separate European cohorts (phase 1 validation cohort; n=2545). Variants associated with alcohol-related cirrhosis in the validation at a false discovery rate of less than 20% were then directly genotyped in 2 additional European validation cohorts (phase 2 validation, n=2068). RESULTS: In the GWAS of the discovery cohort, we identified 50 independent risk loci with genome-wide significance (P < 5 × 10-8). Nine of these loci were significantly associated with alcohol-related cirrhosis in the phase 1 validation cohort; 6 of these 9 loci were significantly associated with alcohol-related cirrhosis in phase 2 validation cohort, at a false discovery rate below 5%. The loci included variants in the mitochondrial amidoxime reducing component 1 gene (MARC1) and the heterogeneous nuclear ribonucleoprotein U like 1 gene (HNRNPUL1). After we adjusted for age, sex, body mass index, and type-2 diabetes in the phase 2 validation cohort, the minor A allele of MARC1:rs2642438 was associated with reduced risk of alcohol-related cirrhosis (adjusted odds ratio, 0.76; P=.0027); conversely, the minor C allele of HNRNPUL1:rs15052 was associated with an increased risk of alcohol-related cirrhosis (adjusted odds ratio, 1.30; P=.020). CONCLUSIONS: In a GWAS of samples from the UKB, we identified and validated (in 5 European cohorts) single-nucleotide polymorphisms that affect risk of alcohol-related cirrhosis in opposite directions: the minor A allele in MARC1:rs2642438 decreases risk, whereas the minor C allele in HNRNPUL1:rs15052 increases risk.


Asunto(s)
Sitios Genéticos , Ribonucleoproteínas Nucleares Heterogéneas/genética , Cirrosis Hepática Alcohólica/genética , Proteínas Mitocondriales/genética , Proteínas Nucleares/genética , Oxidorreductasas/genética , Polimorfismo de Nucleótido Simple , Factores de Transcripción/genética , Adulto , Anciano , Europa (Continente)/epidemiología , Femenino , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Humanos , Cirrosis Hepática Alcohólica/diagnóstico , Cirrosis Hepática Alcohólica/epidemiología , Masculino , Persona de Mediana Edad , Fenotipo , Medición de Riesgo , Factores de Riesgo
11.
Artículo en Inglés | MEDLINE | ID: mdl-31794862

RESUMEN

Solid tumors are characterized by global metabolic alterations which contribute to their growth and progression. Altered gene expression profiles and plasma lipid composition suggested a role for metabolic reprogramming in colorectal cancer (CRC) development. However, a conclusive picture of CRC-associated lipidome alterations in the tumor tissue has not emerged. Here, we determined molar abundances of 342 species from 20 lipid classes in matched biopsies of CRC and adjacent normal mucosa. We demonstrate that in contrast to previous reports, CRC shows a largely preserved lipidome composition that resembles that of normal colonic mucosa. Important exceptions include increased levels of lyso-phosphatidylinositols in CRC and reduced abundance of ether phospholipids in advanced stages of CRC. As such, our observations challenge the concept of widespread alterations in lipid metabolism in CRC and rather suggest changes in the cellular lipid profile that are limited to selected lipids involved in signaling and the scavenging of reactive oxygen species.


Asunto(s)
Neoplasias Colorrectales/metabolismo , Metabolismo de los Lípidos , Anciano , Femenino , Humanos , Mucosa Intestinal/metabolismo , Lipidómica/métodos , Masculino , Metaboloma , Persona de Mediana Edad , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos
12.
Cell Rep ; 29(13): 4553-4567.e7, 2019 12 24.
Artículo en Inglés | MEDLINE | ID: mdl-31875560

RESUMEN

The Hedgehog (Hh) and Wnt/ß-Catenin (Wnt) cascades are morphogen pathways whose pronounced influence on adult liver metabolism has been identified in recent years. How both pathways communicate and control liver metabolic functions are largely unknown. Detecting core components of Wnt and Hh signaling and mathematical modeling showed that both pathways in healthy liver act largely complementary to each other in the pericentral (Wnt) and the periportal zone (Hh) and communicate mainly by mutual repression. The Wnt/Hh module inversely controls the spatiotemporal operation of various liver metabolic pathways, as revealed by transcriptome, proteome, and metabolome analyses. Shifting the balance to Wnt (activation) or Hh (inhibition) causes pericentralization and periportalization of liver functions, respectively. Thus, homeostasis of the Wnt/Hh module is essential for maintaining proper liver metabolism and to avoid the development of certain metabolic diseases. With caution due to minor species-specific differences, these conclusions may hold for human liver as well.


Asunto(s)
Proteínas Hedgehog/metabolismo , Hígado/metabolismo , Proteínas Wnt/metabolismo , Vía de Señalización Wnt , Adulto , Animales , Tipificación del Cuerpo/genética , Femenino , Humanos , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Transcripción Genética , Vía de Señalización Wnt/genética
13.
Nat Med ; 25(12): 1885-1893, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31792455

RESUMEN

Early disease diagnosis is key to the effective treatment of diseases. Histopathological analysis of human biopsies is the gold standard to diagnose tissue alterations. However, this approach has low resolution and overlooks 3D (three-dimensional) structural changes resulting from functional alterations. Here, we applied multiphoton imaging, 3D digital reconstructions and computational simulations to generate spatially resolved geometrical and functional models of human liver tissue at different stages of non-alcoholic fatty liver disease (NAFLD). We identified a set of morphometric cellular and tissue parameters correlated with disease progression, and discover profound topological defects in the 3D bile canalicular (BC) network. Personalized biliary fluid dynamic simulations predicted an increased pericentral biliary pressure and micro-cholestasis, consistent with elevated cholestatic biomarkers in patients' sera. Our spatially resolved models of human liver tissue can contribute to high-definition medicine by identifying quantitative multiparametric cellular and tissue signatures to define disease progression and provide new insights into NAFLD pathophysiology.


Asunto(s)
Colestasis/patología , Imagenología Tridimensional , Hígado/patología , Enfermedad del Hígado Graso no Alcohólico/patología , Canalículos Biliares/patología , Sistema Biliar/patología , Colestasis/diagnóstico , Simulación por Computador , Progresión de la Enfermedad , Diagnóstico Precoz , Humanos , Modelos Biológicos , Enfermedad del Hígado Graso no Alcohólico/diagnóstico
14.
Gut ; 68(5): 854-865, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30661054

RESUMEN

OBJECTIVE: Diverticular disease is a common complex disorder characterised by mucosal outpouchings of the colonic wall that manifests through complications such as diverticulitis, perforation and bleeding. We report the to date largest genome-wide association study (GWAS) to identify genetic risk factors for diverticular disease. DESIGN: Discovery GWAS analysis was performed on UK Biobank imputed genotypes using 31 964 cases and 419 135 controls of European descent. Associations were replicated in a European sample of 3893 cases and 2829 diverticula-free controls and evaluated for risk contribution to diverticulitis and uncomplicated diverticulosis. Transcripts at top 20 replicating loci were analysed by real-time quatitative PCR in preparations of the mucosal, submucosal and muscular layer of colon. The localisation of expressed protein at selected loci was investigated by immunohistochemistry. RESULTS: We discovered 48 risk loci, of which 12 are novel, with genome-wide significance and consistent OR in the replication sample. Nominal replication (p<0.05) was observed for 27 loci, and additional 8 in meta-analysis with a population-based cohort. The most significant novel risk variant rs9960286 is located near CTAGE1 with a p value of 2.3×10-10 and 0.002 (ORallelic=1.14 (95% CI 1.05 to 1.24)) in the replication analysis. Four loci showed stronger effects for diverticulitis, PHGR1 (OR 1.32, 95% CI 1.12 to 1.56), FAM155A-2 (OR 1.21, 95% CI 1.04 to 1.42), CALCB (OR 1.17, 95% CI 1.03 to 1.33) and S100A10 (OR 1.17, 95% CI 1.03 to 1.33). CONCLUSION: In silico analyses point to diverticulosis primarily as a disorder of intestinal neuromuscular function and of impaired connective fibre support, while an additional diverticulitis risk might be conferred by epithelial dysfunction.


Asunto(s)
Enfermedades del Colon/genética , Tejido Conectivo/fisiología , Enfermedades Diverticulares/genética , Epitelio/fisiología , Estudio de Asociación del Genoma Completo , Unión Neuromuscular/fisiología , Adulto , Anciano , Estudios de Casos y Controles , Enfermedades del Colon/patología , Bases de Datos Genéticas , Enfermedades Diverticulares/patología , Femenino , Predisposición Genética a la Enfermedad/genética , Humanos , Masculino , Persona de Mediana Edad , Reino Unido
15.
Gut ; 68(6): 1099-1107, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30068662

RESUMEN

OBJECTIVE: Homozygous alpha1-antitrypsin (AAT) deficiency increases the risk for developing cirrhosis, whereas the relevance of heterozygous carriage remains unclear. Hence, we evaluated the impact of the two most relevant AAT variants ('Pi*Z' and 'Pi*S'), present in up to 10% of Caucasians, on subjects with non-alcoholic fatty liver disease (NAFLD) or alcohol misuse. DESIGN: We analysed multicentric case-control cohorts consisting of 1184 people with biopsy-proven NAFLD and of 2462 people with chronic alcohol misuse, both cohorts comprising cases with cirrhosis and controls without cirrhosis. Genotyping for the Pi*Z and Pi*S variants was performed. RESULTS: The Pi*Z variant presented in 13.8% of patients with cirrhotic NAFLD but only in 2.4% of counterparts without liver fibrosis (p<0.0001). Accordingly, the Pi*Z variant increased the risk of NAFLD subjects to develop cirrhosis (adjusted OR=7.3 (95% CI 2.2 to 24.8)). Likewise, the Pi*Z variant presented in 6.2% of alcohol misusers with cirrhosis but only in 2.2% of alcohol misusers without significant liver injury (p<0.0001). Correspondingly, alcohol misusers carrying the Pi*Z variant were prone to develop cirrhosis (adjusted OR=5.8 (95% CI 2.9 to 11.7)). In contrast, the Pi*S variant was not associated with NAFLD-related cirrhosis and only borderline with alcohol-related cirrhosis (adjusted OR=1.47 (95% CI 0.99 to 2.19)). CONCLUSION: The Pi*Z variant is the hitherto strongest single nucleotide polymorphism-based risk factor for cirrhosis in NAFLD and alcohol misuse, whereas the Pi*S variant confers only a weak risk in alcohol misusers. As 2%-4% of Caucasians are Pi*Z carriers, this finding should be considered in genetic counselling of affected individuals.


Asunto(s)
Predisposición Genética a la Enfermedad/epidemiología , Heterocigoto , Cirrosis Hepática Alcohólica/genética , alfa 1-Antitripsina/genética , Distribución por Edad , Austria , Biopsia con Aguja , Estudios de Casos y Controles , Intervalos de Confianza , Femenino , Tamización de Portadores Genéticos , Variación Genética , Alemania , Humanos , Inmunohistoquímica , Incidencia , Cirrosis Hepática Alcohólica/epidemiología , Cirrosis Hepática Alcohólica/patología , Masculino , Enfermedad del Hígado Graso no Alcohólico/epidemiología , Enfermedad del Hígado Graso no Alcohólico/genética , Enfermedad del Hígado Graso no Alcohólico/patología , Oportunidad Relativa , Polimorfismo de Nucleótido Simple , Pronóstico , Medición de Riesgo , Distribución por Sexo
16.
Nat Commun ; 9(1): 4150, 2018 10 08.
Artículo en Inglés | MEDLINE | ID: mdl-30297808

RESUMEN

A deeper epigenomic understanding of spatial organization of cells in human tissues is an important challenge. Here we report the first combined positional analysis of transcriptomes and methylomes across three micro-dissected zones (pericentral, intermediate and periportal) of human liver. We identify pronounced anti-correlated transcriptional and methylation gradients including a core of 271 genes controlling zonated metabolic and morphogen networks and observe a prominent porto-central gradient of DNA methylation at binding sites of 46 transcription factors. The gradient includes an epigenetic and transcriptional Wnt signature supporting the concept of a pericentral hepatocyte regeneration pathway under steady-state conditions. While donors with non-alcoholic fatty liver disease show consistent gene expression differences corresponding to the severity of the disease across all zones, the relative zonated gene expression and DNA methylation patterns remain unchanged. Overall our data provide a wealth of new positional insights into zonal networks controlled by epigenetic and transcriptional gradients in human liver.


Asunto(s)
Epigenómica , Hepatocitos/metabolismo , Hígado/metabolismo , Morfogénesis/genética , Adulto , Anciano , Animales , Metilación de ADN , Femenino , Perfilación de la Expresión Génica , Humanos , Hígado/anatomía & histología , Hígado/crecimiento & desarrollo , Masculino , Ratones , Persona de Mediana Edad , Enfermedad del Hígado Graso no Alcohólico/genética , Enfermedad del Hígado Graso no Alcohólico/patología
17.
BMC Cancer ; 18(1): 796, 2018 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-30081852

RESUMEN

BACKGROUND: ADAMs (a disintegrin and metalloproteinase) have long been associated with tumor progression. Recent findings indicate that members of the closely related ADAMTS (ADAMs with thrombospondin motifs) family are also critically involved in carcinogenesis. Gene silencing through DNA methylation at CpG loci around e.g. transcription start or enhancer sites is a major mechanism in cancer development. Here, we aimed at identifying genes of the ADAM and ADAMTS family showing altered DNA methylation in the development or colorectal cancer (CRC) and other epithelial tumors. METHODS: We investigated potential changes of DNA methylation affecting ADAM and ADAMTS genes in 117 CRC, 40 lung cancer (LC) and 15 oral squamous-cell carcinoma (SCC) samples. Tumor tissue was analyzed in comparison to adjacent non-malignant tissue of the same patients. The methylation status of 1145 CpGs in 51 ADAM and ADAMTS genes was measured with the HumanMethylation450 BeadChip Array. ADAMTS16 protein expression was analyzed in CRC samples by immunohistochemistry. RESULTS: In CRC, we identified 72 CpGs in 18 genes which were significantly affected by hyper- or hypomethylation in the tumor tissue compared to the adjacent non-malignant tissue. While notable/frequent alterations in methylation patterns within ADAM genes were not observed, conspicuous changes were found in ADAMTS16 and ADAMTS2. To figure out whether these differences would be CRC specific, additional LC and SCC tissue samples were analyzed. Overall, 78 differentially methylated CpGs were found in LC and 29 in SCC. Strikingly, 8 CpGs located in the ADAMTS16 gene were commonly differentially methylated in all three cancer entities. Six CpGs in the promoter region were hypermethylated, whereas 2 CpGs in the gene body were hypomethylated indicative of gene silencing. In line with these findings, ADAMTS16 protein was strongly expressed in globlet cells and colonocytes in control tissue but not in CRC samples. Functional in vitro studies using the colorectal carcinoma cell line HT29 revealed that ADAMTS16 expression restrained tumor cell proliferation. CONCLUSIONS: We identified ADAMTS16 as novel gene with cancer-specific promoter hypermethylation in CRC, LC and SCC patients implicating ADAMTS16 as potential biomarker for these tumors. Moreover, our results provide evidence that ADAMTS16 may have tumor suppressor properties.


Asunto(s)
Proteínas ADAMTS/genética , Biomarcadores de Tumor/genética , Neoplasias Colorrectales/genética , Metilación de ADN , Neoplasias Pulmonares/genética , Neoplasias de la Boca/genética , Carcinoma de Células Escamosas de Cabeza y Cuello/genética , Proteínas ADAMTS/metabolismo , Biomarcadores de Tumor/metabolismo , Proliferación Celular , Neoplasias Colorrectales/enzimología , Neoplasias Colorrectales/patología , Islas de CpG , Epigénesis Genética , Regulación Neoplásica de la Expresión Génica , Predisposición Genética a la Enfermedad , Células HT29 , Humanos , Neoplasias Pulmonares/enzimología , Neoplasias Pulmonares/patología , Neoplasias de la Boca/enzimología , Neoplasias de la Boca/patología , Regiones Promotoras Genéticas , Carcinoma de Células Escamosas de Cabeza y Cuello/enzimología , Carcinoma de Células Escamosas de Cabeza y Cuello/patología
18.
Transplantation ; 102(10): e424-e430, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29994984

RESUMEN

BACKGROUND: Liver transplantation (LTx) is a potentially curative treatment option for hepatocellular carcinoma (HCC) in cirrhosis. However, patients, where HCC is already a systemic disease, LTx may be individually harmful and has a negative impact on donor organ usage. Thus, there is a need for improved selection criteria beyond nodule morphology to select patients with a favorable outcome for LTx in multifocal HCC. Evolutionary distance measured from genome-wide single-nucleotide polymorphism data between tumor nodules and the cirrhotic liver may be a prognostic marker of survival after LTx for multifocal HCC. METHODS: In a retrospective multicenter study, clinical data and formalin-fixed paraffin-embedded specimens of the liver and 2 tumor nodules were obtained from explants of 30 patients in the discovery and 180 patients in the replication cohort. DNA was extracted from formalin-fixed paraffin-embedded specimens followed by genome wide single-nucleotide polymorphism genotyping. RESULTS: Genotype quality criteria allowed for analysis of 8 patients in the discovery and 17 patients in the replication set. DNA concentrations of a total of 25 patients fulfilled the quality criteria and were included in the analysis. Both, in the discovery (P = 0.04) and in the replication data sets (P = 0.01), evolutionary distance was associated with the risk of recurrence of HCC after transplantation (combined P = 0.0002). In a univariate analysis, evolutionary distance (P = 7.4 × 10) and microvascular invasion (P = 1.31 × 10) were significantly associated with survival in a Cox regression analysis. CONCLUSIONS: Evolutionary distance allows for the determination of a high-risk group of recurrence if preoperative liver biopsy is considered.


Asunto(s)
Carcinoma Hepatocelular/genética , Cirrosis Hepática/genética , Neoplasias Hepáticas/genética , Trasplante de Hígado , Recurrencia Local de Neoplasia/diagnóstico , Adulto , Biomarcadores/análisis , Biopsia , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/cirugía , Evolución Molecular , Femenino , Estudios de Seguimiento , Técnicas de Genotipaje , Humanos , Cirrosis Hepática/patología , Cirrosis Hepática/cirugía , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/cirugía , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/genética , Selección de Paciente , Filogenia , Polimorfismo de Nucleótido Simple/genética , Periodo Preoperatorio , Pronóstico , Análisis de Regresión , Estudios Retrospectivos , Resultado del Tratamiento , Secuenciación Completa del Genoma
19.
NPJ Syst Biol Appl ; 3: 11, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28649438

RESUMEN

Early indication of late-stage failure of novel candidate drugs could be facilitated by continuous integration, assessment, and transfer of knowledge acquired along pharmaceutical development programs. We here present a translational systems pharmacology workflow that combines drug cocktail probing in a specifically designed clinical study, physiologically based pharmacokinetic modeling, and Bayesian statistics to identify and transfer (patho-)physiological and drug-specific knowledge across distinct patient populations. Our work builds on two clinical investigations, one with 103 healthy volunteers and one with 79 diseased patients from which we systematically derived physiological information from pharmacokinetic data for a reference probe drug (midazolam) at the single-patient level. Taking into account the acquired knowledge describing (patho-)physiological alterations in the patient cohort allowed the successful prediction of the population pharmacokinetics of a second, candidate probe drug (torsemide) in the patient population. In addition, we identified significant relations of the acquired physiological processes to patient metadata from liver biopsies. The presented prototypical systems pharmacology approach is a proof of concept for model-based translation across different stages of pharmaceutical development programs. Applied consistently, it has the potential to systematically improve predictivity of pharmacokinetic simulations by incorporating the results of clinical trials and translating them to subsequent studies.

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