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1.
J Biol Chem ; 288(29): 21389-21398, 2013 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-23740243

RESUMO

Tissue regeneration requires the activation of a set of specific growth signaling pathways. The identity of these cascades and their biological roles are known; however, the molecular mechanisms regulating the interplay between these pathways remain poorly understood. Here, we define a new role for SULFATASE 2 (SULF2) in regulating tissue regeneration and define the WNT-GLI1 axis as a novel downstream effector for this sulfatase in a liver model of tissue regeneration. SULF2 is a heparan sulfate 6-O-endosulfatase, which releases growth factors from extracellular storage sites turning active multiple signaling pathways. We demonstrate that SULF2-KO mice display delayed regeneration after partial hepatectomy (PH). Mechanistic analysis of the SULF2-KO phenotype showed a decrease in WNT signaling pathway activity in vivo. In isolated hepatocytes, SULF2 deficiency blocked WNT-induced ß-CATENIN nuclear translocation, TCF activation, and proliferation. Furthermore, we identified the transcription factor GLI1 as a novel target of the SULF2-WNT cascade. WNT induces GLI1 expression in a SULF2- and ß-CATENIN-dependent manner. GLI1-KO mice phenocopied the SULF2-KO, showing delayed regeneration and decreased hepatocyte proliferation. Moreover, we identified CYCLIN D1, a key mediator of cell growth during tissue regeneration, as a GLI1 transcriptional target. GLI1 binds to the cyclin d1 promoter and regulates its activity and expression. Finally, restoring GLI1 expression in the liver of SULF2-KO mice after PH rescues CYCLIN D1 expression and hepatocyte proliferation to wild-type levels. Thus, together these findings define a novel pathway in which SULF2 regulates tissue regeneration in part via the activation of a novel WNT-GLI1-CYCLIN D1 pathway.


Assuntos
Fatores de Transcrição Kruppel-Like/metabolismo , Regeneração Hepática , Sulfatases/metabolismo , Via de Sinalização Wnt , Animais , Proliferação de Células/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Proteínas Hedgehog/metabolismo , Hepatectomia , Hepatócitos/citologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Fatores de Transcrição Kruppel-Like/genética , Regeneração Hepática/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Modelos Biológicos , Sulfatases/deficiência , Via de Sinalização Wnt/efeitos dos fármacos , Proteína Wnt3A/farmacologia , Proteína GLI1 em Dedos de Zinco , beta Catenina/metabolismo
2.
Radiology ; 266(3): 964-70, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23220900

RESUMO

PURPOSE: To investigate the value of viscosity measured with ultrasonographic (US) elastography in liver fibrosis staging and to determine whether the use of a viscoelastic model to estimate liver elasticity can improve its accuracy in fibrosis staging. MATERIALS AND METHODS: The study, which was performed from February 2010 to March 2011, was compliant with HIPAA and approved by the institutional review board. Written informed consent was obtained from each subject. Ten healthy volunteers (eight women and two men aged 27-55 years) and 35 patients with liver disease (17 women and 18 men aged 19-74 years) were studied by using US elasticity measurements of the liver (within 6 months of liver biopsy). US data were analyzed with the shear wave dispersion ultrasound vibrometry (SDUV) method, in which elasticity and viscosity are measured by evaluating dispersion of shear wave propagation speed, as well as with the time-to-peak (TTP) method, where tissue viscosity was neglected and only elasticity was estimated from the effective shear wave speed. The hepatic fibrosis stage was assessed histologically by using the METAVIR scoring system. The correlation of elasticity and viscosity was assessed with the Pearson correlation coefficient. The performances of SDUV and TTP were evaluated with receiver operating characteristic (ROC) curve analysis. RESULTS: The authors found significant correlations between elasticity and viscosity measured with SDUV (r = 0.80) and elasticity measured with SDUV and TTP (r = 0.94). The area under the ROC curve for differentiating between grade F0-F1 fibrosis and grade F2-F4 fibrosis was 0.98 for elasticity measured with SDUV, 0.86 for viscosity measured with SDUV, and 0.95 for elasticity measured with TTP. CONCLUSION: The results suggest that elasticity and viscosity measured between 95 Hz and 380 Hz by using SDUV are correlated and that elasticity measurements from SDUV and TTP showed substantially similar performance in liver fibrosis staging, although elasticity calculated from SDUV provided a better area under the ROC curve.


Assuntos
Técnicas de Imagem por Elasticidade/métodos , Interpretação de Imagem Assistida por Computador/métodos , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/fisiopatologia , Fígado/diagnóstico por imagem , Fígado/fisiopatologia , Adulto , Idoso , Simulação por Computador , Módulo de Elasticidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Resistência ao Cisalhamento , Viscosidade
3.
Hepatology ; 56(2): 614-21, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22370914

RESUMO

UNLABELLED: Survival of patients with hepatocellular carcinoma (HCC) is determined by the extent of the tumor and the underlying liver function. We aimed to develop a survival model for HCC based on objective parameters including the Model for Endstage Liver Disease (MELD) as a gauge of liver dysfunction. This analysis is based on 477 patients with HCC seen at Mayo Clinic Rochester between 1994 and 2008 (derivation cohort) and 904 patients at the Korean National Cancer Center between 2000 and 2003 (validation cohort). Multivariate proportional hazards models and corresponding risk score were created based on baseline demographic, clinical, and tumor characteristics. Internal and external validation of the model was performed. Discrimination and calibration of this new model were compared against existing models including Barcelona Clinic Liver Cancer (BCLC), Cancer of the Liver Italian Program (CLIP), and Japan Integrated Staging (JIS) scores. The majority of the patients had viral hepatitis as the underlying liver disease (100% in the derivation cohort and 85% in the validation cohort). The survival model incorporated MELD, age, number of tumor nodules, size of the largest nodule, vascular invasion, metastasis, serum albumin, and alpha-fetoprotein. In cross-validation, the coefficients remained largely unchanged between iterations. Observed survival in the validation cohort matched closely with what was predicted by the model. The concordance (c)-statistic for this model (0.77) was superior to that for BCLC (0.71), CLIP (0.70), or JIS (0.70). The score was able to further classify patient survival within each stage of the BCLC classification. CONCLUSION: A new model to predict survival of HCC patients based on objective parameters provides refined prognostication and supplements the BCLC classification.


Assuntos
Assistência Ambulatorial/estatística & dados numéricos , Carcinoma Hepatocelular/mortalidade , Neoplasias Hepáticas/mortalidade , Modelos Estatísticos , Idoso , Carcinoma Hepatocelular/patologia , Estudos de Coortes , Feminino , Seguimentos , Humanos , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias/mortalidade , Estadiamento de Neoplasias/normas , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Reprodutibilidade dos Testes , Fatores de Risco
4.
Clin Gastroenterol Hepatol ; 10(9): 1028-33.e2, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22610002

RESUMO

BACKGROUND & AIMS: Little is known about the prevalence and severity of portal hypertension in patients with nonalcoholic fatty liver disease (NAFLD). We investigated the prevalence and noninvasive predictors of portal hypertension in patients with NAFLD. METHODS: Signs of portal hypertension, including esophageal varices, splenomegaly, portosystemic encephalopathy, and ascites, were investigated in 354 patients with NAFLD. RESULTS: One hundred patients had portal hypertension at the time of NAFLD diagnosis (28.2%), 88 of these patients had septal fibrosis or cirrhosis (88%). Fibrosis stage correlated with presence (r = 0.41, P < .0001) and number of findings (r = 0.48, P = .006) of portal hypertension. Of the 204 patients with no or mild fibrosis (stages, 0-2), 12 patients had portal hypertension (6%); they had a significantly higher grade of steatosis, based on biopsy analysis, compared with the 192 patients without portal hypertension (94%). Thrombocytopenia, hyperbilirubinemia, cirrhosis, and obesity were associated independently with portal hypertension. Esophageal varices were found in 57 of the 128 patients undergoing endoscopic screening (44.5%) and were associated independently with thrombocytopenia, type 2 diabetes, and splenomegaly. CONCLUSIONS: Signs of portal hypertension were present in 25% of patients at the time of diagnosis of NAFLD; most had advanced fibrosis or cirrhosis. Portal hypertension can occur in a small proportion of patients with mild or no fibrosis and is associated with the extent of steatosis. Features of advanced liver disease and insulin resistance might identify patients with NAFLD and portal hypertension, and those expected to derive the most benefit from endoscopic screening for esophageal varices.


Assuntos
Fígado Gorduroso/complicações , Hipertensão Portal/diagnóstico , Hipertensão Portal/epidemiologia , Adulto , Ascite/diagnóstico , Ascite/epidemiologia , Ascite/patologia , Varizes Esofágicas e Gástricas/diagnóstico , Varizes Esofágicas e Gástricas/epidemiologia , Varizes Esofágicas e Gástricas/patologia , Feminino , Encefalopatia Hepática/diagnóstico , Encefalopatia Hepática/epidemiologia , Encefalopatia Hepática/patologia , Humanos , Hipertensão Portal/patologia , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica , Prevalência , Esplenomegalia/diagnóstico , Esplenomegalia/epidemiologia , Esplenomegalia/patologia
5.
Am J Gastroenterol ; 107(8): 1256-62, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22751468

RESUMO

OBJECTIVES: The epidemiology of biliary tract cancers has changed in the United States in the past several decades. The aim of this study is to evaluate biliary tract cancers with regard to the incidence rates, etiology, treatment, and survival in Olmsted County between 1976 and 2008. METHODS: Community residents over 20 years of age with a newly diagnosed biliary tract cancers were identified using the Rochester Epidemiology Project. Clinical information, including tumor stage, treatment, and survival status was abstracted from the medical records. The incidence rate was calculated considering the entire population of Olmsted County to be at risk and adjusted by age and sex according to US Census 2000 population. Temporal trends of patient survival with biliary tract cancers were assessed. RESULTS: A total of 116 subjects met the study criteria. The age-sex-adjusted incidence rate of intrahepatic cholangiocarcinoma (ICC) increased from 0.3 to 2.1 (P=0.02) but one of gall bladder (GB) cancer decreased from 4.0 to 2.2 (P=0.04) per 100,000 person-years between 1976 and 2008 (P<0.01). Overall incidence rates of remaining biliary tract cancers have not changed. Overall 59% of patients presented with stage 3 or 4 cancers and a median survival was 6.3 months. Survival in patients with biliary tract cancer has minimally improved from median survival of 4.2-7.7 months between 1976 and 2008 (P=0.05). CONCLUSIONS: In Olmsted County, the incidence of ICC and GB cancer has increased and decreased, respectively. The prognosis remains poor in community residents diagnosed with biliary tract cancers.


Assuntos
Neoplasias do Sistema Biliar/epidemiologia , Idoso , Neoplasias dos Ductos Biliares/epidemiologia , Neoplasias dos Ductos Biliares/mortalidade , Neoplasias dos Ductos Biliares/cirurgia , Ductos Biliares Intra-Hepáticos , Neoplasias do Sistema Biliar/mortalidade , Neoplasias do Sistema Biliar/cirurgia , Colangiocarcinoma/epidemiologia , Colangiocarcinoma/cirurgia , Colecistectomia , Feminino , Neoplasias da Vesícula Biliar/epidemiologia , Neoplasias da Vesícula Biliar/cirurgia , Humanos , Incidência , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/cirurgia , Masculino , Minnesota/epidemiologia , Prognóstico , Taxa de Sobrevida
6.
Liver Transpl ; 18(7): 803-10, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22389256

RESUMO

Drug-induced liver injury (DILI) is increasingly being recognized as a common cause of acute hepatitis. The clinical impact of DILI after liver transplantation (LT) is not known. The aim of this study was to describe the frequency, clinical presentation, and outcomes of DILI in LT recipients. LT recipients with possible DILI were identified with electronic pathology records and clinical note database retrieval tools. Diagnostic criteria were applied to identify cases of DILI. Twenty-nine of 1689 LT recipients (1.7%) were identified with DILI. The mean age was 52 years, and 52% were women. The major indications for LT were primary sclerosing cholangitis (28%), cholangiocarcinoma (14%), and hepatocellular carcinoma (14%). The severity of DILI was mild or moderate in 92% of the cases. Nausea or diarrhea (31%), jaundice (24%), and pruritus (10%) were the most common symptoms at the time of diagnosis. The mean biochemistry values were as follows: alanine aminotransferase, 204 ± 263 U/L; aspartate aminotransferase, 108 ± 237 U/L; alkaline phosphatase, 469 ± 689 U/L; and total bilirubin, 1.9 ± 10.3 mg/dL. The median duration of medication use until the diagnosis of DILI was 57 days, and the major agent classes were antibiotics (48%), immunosuppressive agents (14%), and antihyperlipidemic drugs (7%). Trimethoprim-sulfamethoxazole was the most common implicated agent (n = 11). Serum liver enzymes improved within a median time of 34 days (range = 5-246 days) after drug withdrawal. Hepatic retransplantation or death did not occur. Among the 50 cases with possible DILI explained by other causes, 13 individuals (26%) had no alternative diagnosis despite histological findings compatible with DILI. In conclusion, DILI is a rare yet underrecognized event among LT recipients. The majority of cases are not clinically severe, and they resolve after drug cessation without hepatic retransplantation or death.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/diagnóstico , Transplante de Fígado/métodos , Fígado/efeitos dos fármacos , Adolescente , Adulto , Idoso , Biópsia , Doença Hepática Induzida por Substâncias e Drogas/terapia , Criança , Pré-Escolar , Feminino , Humanos , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Reoperação , Doadores de Tecidos , Resultado do Tratamento
7.
Dig Dis Sci ; 57(2): 496-502, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21881972

RESUMO

BACKGROUND AND AIMS: Cronkhite-Canada syndrome (CCS) is a noninherited condition, associated with high morbidity, and characterized by gastrointestinal hamartomatous polyposis, alopecia, onychodystrophy, hyperpigmentation, and diarrhea. All features may respond to immunosuppressive therapy, but little is known about the etiology. An autoimmune origin has been suggested but not proved. From a retrospectively selected cohort, we evaluated clinicopathologic features, including immunostaining for IgG4 (an antibody associated with autoimmunity), and therapeutic outcomes in a cohort of CCS patients to provide further insights into this disease. METHODS: Cases included 14 consecutive CCS patients seen at the Mayo Clinic on whom tissue and follow-up were available. All histology was reviewed by an expert gastrointestinal pathologist. Immunostaining for IgG4 was performed on 42 polyps from CCS cases and on control tissues, including 46 histologically similar hamartomas [from juvenile polyposis syndrome (JPS)] and 20 normal mucosae (six stomach, three small bowel, and 11 colon). Clinical features and treatment outcomes were descriptive. RESULTS: All CCS cases had both upper and lower gastrointestinal polyps; most had typical dermatologic features of alopecia, hyperpigmentation, and onychodystrophy; and most had evidence of protein-losing enteropathy. Ten patients (71%) had adenomatous polyps and 2 (14%) had colorectal cancer. IgG4 immunostaining was positive (>5 cells/HPF) in 52% of CCS polyps compared to 12% of JPS polyps (P = 0.001); IgG4 staining was negative in all other control tissues. Of 11 CCS patients treated with oral corticosteroids, 91% achieved remission. Relapse was common with steroid tapering. Five patients who initially responded to corticosteroids were maintained in remission on azathioprine (2 mg/kg/day) with no relapse after a median of 4.5 years. CONCLUSIONS: Immunostaining for the autoimmune-related IgG4 antibody is significantly increased in CCS polyps compared to disease and normal control tissues. Furthermore, immunosuppression by corticosteroids or long-term azathioprine may eradicate or lessen manifestations of CCS. These histologic findings and treatment responses are consistent with an autoimmune mechanism underlying CCS.


Assuntos
Azatioprina/uso terapêutico , Glucocorticoides/uso terapêutico , Imunoglobulina G/imunologia , Imunossupressores/uso terapêutico , Polipose Intestinal/imunologia , Idoso , Doenças Autoimunes/patologia , Feminino , Humanos , Imuno-Histoquímica , Polipose Intestinal/patologia , Polipose Intestinal/fisiopatologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
8.
Clin Gastroenterol Hepatol ; 9(1): 64-70, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20831903

RESUMO

BACKGROUND & AIMS: There are few data available about the prevalence or effects of cirrhosis in patients with hepatocellular carcinoma (HCC) from viral hepatitis. We compared patients with HCC and hepatitis B virus (HBV) or hepatitis C virus (HCV) infections to determine the proportions of cirrhosis in each group, virologic and tumor characteristics, and overall survival. METHODS: This analysis included patients with HBV (n = 64) or HCV (n = 118) infection who were diagnosed with HCC at the Mayo Clinic in Rochester, Minnesota from 1994-2008; groups were matched for age and sex. The diagnosis of cirrhosis was based on histology and, if histologic information was insufficient or unavailable, clinical indicators that included ascites or varices, thrombocytopenia or splenomegaly, and radiographic configuration of cirrhosis. Virologic characteristics, tumor stage, and patient survival were also assessed. RESULTS: The prevalence of histologic cirrhosis was 88% among patients with HBV infection and 93% among those with HCV infection (P = .46). When the most inclusive criteria for cirrhosis were applied, cirrhosis was present in 94% of patients with HBV and 97% with HCV (P = .24). Among HCV patients, 5.2% were negative for HCV RNA after antiviral treatment; 63.4% of HBV patients had HBV DNA <2000 IU/mL with or without treatment. Patients with HBV tended to have less surveillance and more advanced stages of HCC, without differences in survival from those with HCV infection (P = .75). CONCLUSIONS: Most patients with HCC and chronic viral hepatitis had evidence of cirrhosis, including those with HBV infection and those without active viral replication.


Assuntos
Carcinoma Hepatocelular/complicações , Carcinoma Hepatocelular/patologia , Fibrose/epidemiologia , Fibrose/patologia , Hepatite B Crônica/complicações , Hepatite B Crônica/patologia , Idoso , Ascite/diagnóstico , Varizes Esofágicas e Gástricas/diagnóstico , Feminino , Hepatite C Crônica/complicações , Hepatite C Crônica/patologia , Histocitoquímica , Humanos , Masculino , Pessoa de Meia-Idade , Minnesota/epidemiologia , Prevalência , Esplenomegalia/diagnóstico , Trombocitopenia/diagnóstico
9.
Radiology ; 259(3): 749-56, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21460032

RESUMO

PURPOSE: To investigate the diagnostic accuracy (area under the receiver operating characteristic curve [AUROC]) of magnetic resonance (MR) elastography for the early detection of nonalcoholic steatohepatitis (NASH) among patients with nonalcoholic fatty liver disease (NAFLD). MATERIALS AND METHODS: An institutional review board-approved and HIPAA-compliant retrospective study was conducted in 58 NAFLD patients. Informed consent was waived by the review board. Hepatic stiffness, relative fat fraction, inflammation grade, and fibrosis stage were assessed from MR elastography, in-phase and out-of-phase gradient-echo imaging, and liver biopsy histopathologic review, respectively. Pairwise t testing, receiver operating characteristic analysis, and partial correlation analysis were performed. RESULTS: The mean hepatic stiffness for patients with simple steatosis (2.51 kPa) was less (P = .028) than that for patients with inflammation but no fibrosis (3.24 kPa). The mean hepatic stiffness for patients with inflammation but no fibrosis was less (P = .030) than that for patients with hepatic fibrosis (4.16 kPa). Liver stiffness had high accuracy (AUROC = 0.93) for discriminating patients with NASH from those with simple steatosis, with a sensitivity of 94% and a specificity 73% by using a threshold of 2.74 kPa. CONCLUSION: In patients with NAFLD, hepatic stiffness measurements with MR elastography can help identify individuals with steatohepatitis, even before the onset of fibrosis; NAFLD patients with inflammation but no fibrosis have greater liver stiffness than those with simple steatosis and lower mean stiffness than those with fibrosis.


Assuntos
Técnicas de Imagem por Elasticidade/métodos , Adulto , Idoso , Área Sob a Curva , Biópsia , Fígado Gorduroso/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica , Curva ROC , Estudos Retrospectivos
10.
Hepatology ; 52(5): 1680-9, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20725905

RESUMO

UNLABELLED: Heparan sulfate proteoglycans (HSPGs) act as coreceptors or storage sites for growth factors and cytokines such as fibroblast growth factor and Wnts. Glypican 3 (GPC3) is the most highly expressed HSPG in hepatocellular carcinoma (HCC). Sulfatase 2 (SULF2), an enzyme with 6-O-desulfatase activity on HSPGs, is up-regulated in 60% of primary HCCs and is associated with a worse prognosis. We have previously shown that the oncogenic effect of SULF2 in HCC may be mediated in part through up-regulation of GPC3. Here we demonstrate that GPC3 stimulates the Wnt/ß-catenin pathway and mediates the oncogenic function of SULF2 in HCC. Wnt signaling in vitro and in vivo was assessed in SULF2-negative Hep3B HCC cells transfected with SULF2 and in SULF2-expressing Huh7 cells transfected with short hairpin RNA targeting SULF2. The interaction between GPC3, SULF2, and Wnt3a was assessed by coimmunoprecipitation and flow cytometry. ß-catenin-dependent transcriptional activity was assessed with the TOPFLASH (T cell factor reporter plasmid) luciferase assay. In HCC cells, SULF2 increased cell surface GPC3 and Wnt3a expression, stabilized ß-catenin, and activated T cell factor transcription factor activity and expression of the Wnt/ß-catenin target gene cyclin D1. Opposite effects were observed in SULF2-knockdown models. In vivo, nude mouse xenografts established from SULF2-transfected Hep3B cells showed enhanced GPC3, Wnt3a, and ß-catenin levels. CONCLUSION: Together, these findings identify a novel mechanism mediating the oncogenic function of SULF2 in HCC that includes GPC3-mediated activation of Wnt signaling via the Wnt3a/glycogen synthase kinase 3 beta axis.


Assuntos
Carcinoma Hepatocelular/enzimologia , Neoplasias Hepáticas/enzimologia , Sulfotransferases/sangue , Animais , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Caspase 3/metabolismo , Linhagem Celular Tumoral , Ativação Enzimática , Citometria de Fluxo , Regulação Neoplásica da Expressão Gênica , Genes Reporter , Glipicanas/sangue , Glipicanas/genética , Humanos , Antígeno Ki-67/genética , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Luciferases/genética , Camundongos , Camundongos Nus , Plasmídeos/genética , Sulfatases , Transfecção , Proteínas Wnt/genética , Proteína Wnt3 , Proteína Wnt3A
11.
J Magn Reson Imaging ; 34(4): 947-55, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21751289

RESUMO

PURPOSE: To conduct a rigorous evaluation of the repeatability of liver stiffness assessed by MR elastography (MRE) in healthy and hepatitis-C-infected subjects. MATERIALS AND METHODS: A biopsy-correlated repeatability study using four-slice MRE was conducted in five healthy and four HCV-infected subjects. Subjects were scanned twice on day 1 and after 7-14 days. Each slice was acquired during a 14-s breath-hold with a commercially available acquisition technique (MR-Touch, GE Healthcare). Results were analyzed by two independent analysts. RESULTS: The intraclass correlation coefficient (ICC) was 0.85 (90% confidence interval [CI]: 0.71 to 0.98) for the between-scan average of maximum stiffness within each slice and 0.88 (90% CI: 0.78 to 0.99) for the average of mean stiffness within each slice for the primary analyst. For both analysts, the average of the mean liver stiffness within each slice was highly reproducible with ICC of 0.93 and 0.94. Within-subject coefficients of variation ranged from 6.07% to 10.78% for HCV+ and healthy subjects. CONCLUSION: MRE is a highly reproducible modality for assessing liver stiffness in HCV patients and healthy subjects and can discriminate between moderate fibrosis and healthy liver. MRE is a promising modality for noninvasive assessment of liver fibrosis (CLINICALTRIALS.GOV IDENTIFIER: NCT00896233).


Assuntos
Técnicas de Imagem por Elasticidade/métodos , Hepatite C Crônica/diagnóstico , Processamento de Imagem Assistida por Computador , Cirrose Hepática/diagnóstico , Imageamento por Ressonância Magnética/métodos , Adulto , Biópsia por Agulha , Estudos de Casos e Controles , Feminino , Hepatite C Crônica/complicações , Humanos , Imuno-Histoquímica , Cirrose Hepática/etiologia , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Valores de Referência , Reprodutibilidade dos Testes , Índice de Gravidade de Doença , Adulto Jovem
12.
J Clin Gastroenterol ; 45(2): 153-8, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20502350

RESUMO

BACKGROUND: The metabolic fates of copper and iron are closely linked through ceruloplasmin and hephaestin. Ceruloplasmin is the principal copper carrying protein and decreases in acquired copper deficiency. Congenital absence of ceruloplasmin (aceruloplasminemia) results in tissue iron overload. Animal studies suggest hypoceruloplasminemia and impaired hephaestin function result in tissue iron accumulation. OBJECTIVES: There are no data on hepatic function, pathology, and iron status in patients with acquired copper deficiency. This report studies these issues in 4 patients with acquired copper deficiency. STUDY: This is a retrospective review of hepatic status (imaging, liver function tests, liver biopsy) in 4 patients with neurologic and hematologic manifestations of acquired copper deficiency who also had imaging and/or pathologic evidence of hepatic dysfunction. RESULTS: Two patients (cases 1 and 2) showed imaging evidence of cirrhosis and pathologic evidence of cirrhosis or advanced fibrosis. Two patients (cases 3 and 4) had pathologic evidence of hepatic iron overload. All patients had some evidence of abnormality on liver function tests. CONCLUSIONS: Acquired copper deficiency causes a secondary ceruloplasmin deficiency which can result in hepatic iron overload and/or cirrhosis.


Assuntos
Ceruloplasmina/deficiência , Cobre/deficiência , Doenças Hematológicas/etiologia , Sobrecarga de Ferro/etiologia , Cirrose Hepática/etiologia , Fígado/patologia , Idoso , Biópsia , Cobre/metabolismo , Humanos , Sobrecarga de Ferro/complicações , Sobrecarga de Ferro/metabolismo , Sobrecarga de Ferro/patologia , Fígado/metabolismo , Cirrose Hepática/complicações , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Testes de Função Hepática , Pessoa de Meia-Idade , Doenças do Sistema Nervoso/etiologia
13.
Hepatology ; 50(6): 1818-26, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19824078

RESUMO

UNLABELLED: Based on animal studies and pilot studies in humans, betaine, a methyl donor for the remethylation of homocysteine, may be a therapeutic agent for nonalcoholic steatohepatitis (NASH). We evaluated the safety and efficacy of betaine for patients with NASH and whether betaine positively modified factors postulated to be "second hits" and underlying mechanisms of NASH. We conducted a randomized placebo-control study of 55 patients with biopsy-proven NASH who received either oral betaine (20 g daily) or placebo for 12 months. Pre- and posttreatment variables were analyzed using the paired t test or Wilcoxon rank test. Treatment groups were comparable at baseline. Of the 35 patients (17 betaine, 18 placebo) who completed the study, 34 patients (16 betaine, 18 placebo) underwent posttreatment liver biopsy. Patients randomized to betaine had a decrease in steatosis grade. No intra- or intergroup differences or changes in nonalcoholic fatty liver disease activity score or fibrosis stage were noted. Elevations of insulin, glucose, and proinflammatory cytokines and the reduced antioxidant status noted in NASH patients did not improve with betaine therapy. The antiinflammatory agent adiponectin was significantly reduced in both groups and did not change with therapy. Lastly, S-adenosylhomocysteine was approximately twice normal and was not reduced by betaine therapy. CONCLUSION: Compared to placebo, betaine did not improve hepatic steatosis but may protect against worseningsteatosis [corrected]. High-dose betaine supplementation failed to reduce S-adenosylhomocysteine and did not positively affect any of the second hit mechanisms postulated to contribute to NASH that we studied. Although betaine has been proven effective in treating hepatic steatosis in several animal models, translating novel therapeutic options noted in animal studies to humans with NASH will prove challenging.


Assuntos
Betaína/uso terapêutico , Fígado Gorduroso/tratamento farmacológico , Adipocinas/sangue , Adulto , Idoso , Betaína/efeitos adversos , Citocinas/sangue , Método Duplo-Cego , Fígado Gorduroso/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , S-Adenosil-Homocisteína/sangue
14.
Am J Surg Pathol ; 44(6): 793-798, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31934919

RESUMO

Colon polypectomy can require an injection of a submucosal lifting agent to fully visualize and completely remove the polyp. To the best of our knowledge, this is the largest morphologic series on the novel lifting agents Eleview and Orise. The study consisted of 1 polypectomy and 8 colon resections from 9 patients: 6 women, 3 men (mean age=64 y); Orise=6, Eleview=3; the median time interval between injection and resection=16 weeks. Pathologic diagnoses of the polyps included tubular adenoma (n=4), tubulovillous adenoma (n=4), and sessile serrated adenoma/polyp (n=1). We report that a histologically processed Orise aliquot from the manufacturer showed similar histology to that seen in the specimens from patients with confirmed Orise injection. The morphology of the agents in the patient specimens changed with time status postinjection: immediate resection of the lifting agent showed basophilic, amorphous, and bubbly-extracellular material with prominent hemorrhage, and resection ∼3 months after lifting agent injection showed prominent hyalinized, pink-amorphous ribbons and globules with a foreign body giant cell reaction and fibrosis. The epicenter of the lifting agents was in the submucosa, and the agents were neither refractile nor polarizable. Because of the morphologic overlap with amyloid, 5 cases were stained with Congo Red, and all cases were negative. In conclusion, awareness of the morphology of these new lifting agents is important for accurate diagnosis and to avoid the diagnostic pitfall of amyloid. These lesions can be definitively distinguished from amyloid by their nonreactivity on a Congo Red and familiarity with their characteristic clinicopathologic presentation.


Assuntos
Amiloidose/patologia , Pólipos do Colo/patologia , Pólipos do Colo/cirurgia , Procedimentos Cirúrgicos do Sistema Digestório/métodos , Poloxâmero , Amiloidose/diagnóstico , Pólipos do Colo/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Poloxâmero/efeitos adversos
15.
J Hepatol ; 50(6): 1112-21, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19376607

RESUMO

BACKGROUND/AIMS: There are limited chemotherapy options for hepatocellular carcinoma (HCC). The heparin-degrading endosulfatase SULF1 functions as a liver tumor suppressor. We investigated the effects of the histone deacetylase inhibitor apicidin in combination with doxorubicin in SULF1-expressing HCC cells in vitro and in SULF1-expressing xenografts in nude mice. METHODS: We evaluated the effects of apicidin alone or combined with doxorubicin on apoptosis, caspase activity, and phosphorylation of Erk and Akt in SULF1-transfected Huh7 and Hep3B cells in vitro and in vivo. RESULTS: Apicidin induced HCC cell apoptosis and caspase activation in a dose- and time-dependent manner. Apicidin-induced caspase activation was significantly inhibited by the caspase inhibitor Z-Vad-fmk. Apicidin also decreased phosphorylation of both Erk and Akt. Expression of constitutively-active Mek1 and Akt significantly decreased apicidin-induced apoptosis. The combination of doxorubicin with apicidin significantly increased the anti-tumor effect in the SULF1-expressing Huh7 and Hep3B cells as compared to either apicidin or doxorubicin alone, both in vitro and in vivo. CONCLUSIONS: The combination of a histone deacetylase inhibitor with doxorubicin may be a novel and promising therapeutic modality for HCCs, particularly for SULF1-expressing HCCs.


Assuntos
Doxorrubicina/administração & dosagem , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Neoplasias Hepáticas Experimentais/enzimologia , Peptídeos Cíclicos/administração & dosagem , Sulfotransferases/metabolismo , Animais , Antibióticos Antineoplásicos/administração & dosagem , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Inibidores Enzimáticos/administração & dosagem , Inibidores de Histona Desacetilases , Humanos , Neoplasias Hepáticas Experimentais/patologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Camundongos , Camundongos Nus , Transplante de Neoplasias , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Sulfotransferases/genética , Transfecção , Transplante Heterólogo
16.
Am J Gastroenterol ; 104(4): 972-5, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19259073

RESUMO

OBJECTIVES: Our institution has had problems with mislabeling of tissue specimens in our gastrointestinal and colorectal surgery endoscopy units. Most labeling errors have been due to either the wrong patient label or no label being affixed to a specimen bottle. As a result, an initiative was created to reduce the number of specimen-labeling errors. This initiative involved the application of radiofrequency identification (RFID) technology to specimen bottles, moving to a paperless pathology requisition system and confirmation of the correct site and correct patient by both the endoscopy nursing staff and the endoscopist for each specimen bottle. METHODS: We reviewed the number of specimen-labeling errors from our endoscopy unit for the first 3 months of 2007, before the implementation of the initiative, and for the first 3 months of 2008, 6 months after the initiation of RFID specimen labeling with paperless requisition and two-provider confirmation of correct site, correct patient specimen labeling. The RFID system we used was an off-the-shelf 3M (St. Paul, MN) Library Sciences RFID system modified and installed for our purposes. Specimen-labeling errors were categorized as Class 1 (only typographical with no potential clinical consequences), Class 2 (minor error, unlikely to have clinical consequences) or Class 3 (significant error that has the potential to detrimentally impact patient care). The Fischer's exact test was used to compare the rate of specimen-bottle labeling errors before and after the initiation of this new system. RESULTS: In the first 3 months of 2007, our endoscopy unit sent 8,231 specimen bottles to our pathology laboratory for evaluation; 8,539 bottles were sent in the first 3 months of 2008. There were 646 (7.85%) Class 1 errors in the first quarter of 2007 and 35 (0.41%) in the first quarter of 2008 (P<0.001). There were 112 (1.36%) Class 2 errors in the first quarter of 2007 and 10 (0.12%) in the first quarter of 2008 (P<0.001). Finally, in the first quarter of 2007 there were seven (0.09%) Class 3 errors and in the first quarter of 2008, there were two (0.02%) Class 3 errors. However, with the new system in place, both Class 3 errors in the first quarter of 2008 were recognized and corrected before the processing of the specimens in the pathology laboratory (P=0.001). CONCLUSIONS: These data confirm that the initiation of a new specimen-labeling system that uses RFID technology, a paperless requisition process, and confirmation of the correct site and correct patient by two health-care providers significantly decreased specimen-labeling errors at every level in a high-volume endoscopy center.


Assuntos
Endoscopia/normas , Erros Médicos/prevenção & controle , Patologia Clínica/métodos , Sistemas de Identificação de Pacientes/normas , Garantia da Qualidade dos Cuidados de Saúde , Manejo de Espécimes/normas , Endoscopia/estatística & dados numéricos , Humanos , Erros Médicos/tendências , Estudos Retrospectivos , Manejo de Espécimes/métodos
17.
Hepatology ; 47(1): 332-42, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18161879

RESUMO

Chronic liver disease and cirrhosis remains a major public health problem worldwide. While the majority of complications from chronic liver disease result from progressive hepatic fibrosis, the available diagnostic tests used in clinical practice are not sensitive or specific enough to detect occult liver injury at early or intermediate stages. While liver biopsy can stage the extent of fibrosis at diagnosis, its utility as a tool for longitudinal monitoring will be limited at the population level. To date, a number of methods including serum marker panels and ultrasound-based transient elastrography have been proposed for the non-invasive identification of hepatic fibrosis. Novel techniques including magnetic resonance (MR) spectroscopy, diffusion weighted MR, and MR elastography have also emerged for detecting fibrosis. In contrast to other non-invasive methods, MR imaging holds the promise of providing functional and biological information about hepatic pathophysiology as it relates to the natural history and future treatment of hepatic fibrosis. (HEPATOLOGY 2007.).


Assuntos
Cirrose Hepática/diagnóstico , Fígado/patologia , Imageamento por Ressonância Magnética , Ensaios Clínicos como Assunto , Humanos
18.
Hepatology ; 47(4): 1211-22, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18318435

RESUMO

UNLABELLED: It has been shown that the heparin-degrading endosulfatase, sulfatase 1 (SULF1), functions as a liver tumor suppressor, but the role of the related sulfatase, sulfatase 2 (SULF2), in liver carcinogenesis remains to be elucidated. We investigated the effect of SULF2 on liver tumorigenesis. Expression of SULF2 was increased in 79 (57%) of 139 hepatocellular carcinomas (HCCs) and 8 (73%) of 11 HCC cell lines. Forced expression of SULF2 increased HCC cell growth and migration, whereas knockdown of SULF2 using short hairpin RNA targeting SULF2 abrogated HCC cell proliferation and migration in vitro. Because SULF1 and SULF2 desulfate heparan sulfate proteoglycans (HSPGs) and the HSPG glypican 3 (GPC3) is up-regulated in HCC, we investigated the effects of SULF2 on GPC3 expression and the association of SULF2 with GPC3. SULF2-mediated cell growth was associated with increased binding of fibroblast growth factor 2 (FGF2), phosphorylation of extracellular signal-regulated kinase and AKT, and expression of GPC3. Knockdown of GPC3 attenuated FGF2 binding in SULF2-expressing HCC cells. The effects of SULF2 on up-regulation of GPC3 and tumor growth were confirmed in nude mouse xenografts. Moreover, HCC patients with increased SULF2 expression in resected HCC tissues had a worse prognosis and a higher rate of recurrence after surgery. CONCLUSION: In contrast to the tumor suppressor effect of SULF1, SULF2 has an oncogenic effect in HCC mediated in part through up-regulation of FGF signaling and GPC3 expression.


Assuntos
Carcinoma Hepatocelular/enzimologia , Fator 2 de Crescimento de Fibroblastos/metabolismo , Glipicanas/metabolismo , Neoplasias Hepáticas/enzimologia , Sulfotransferases/metabolismo , Animais , Carcinoma Hepatocelular/diagnóstico , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Proliferação de Células , Humanos , Neoplasias Hepáticas/diagnóstico , Camundongos , Camundongos Nus , Prognóstico , Transdução de Sinais/fisiologia , Sulfatases , Regulação para Cima
19.
Am J Gastroenterol ; 103(4): 928-36, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18371145

RESUMO

OBJECTIVES: Noninvasive serum markers of liver fibrosis are being used as an alternative to liver biopsy. Currently available tests distinguish, with accuracy, only absent/minimal fibrosis (Ishak stages 0-1) and advanced fibrosis/cirrhosis (Ishak stages 4-6), but not intermediate fibrosis (Ishak stages 2-3). Our aim was to evaluate the diagnostic accuracy of hyaluronic acid (HA), FIBROSpect II (FS-II), and YKL-40 (chondrex, human cartilage glycoprotein-39) in various clinically important categories of fibrosis, and further correlate these serum markers with digital quantification of fibrosis (DQF) and Ishak stages. METHODS: Serum HA, YKL-40, and FS-II were retrospectively assessed and correlated with Ishak stages and DQF scores in 75 patients with chronic hepatitis C (HCV). Spearman's rho statistics assessed relationships among all parameters, and receiver operator characteristic curves evaluated accuracy of each parameter when compared to the Ishak stages. RESULTS: All three serum markers and DQF correlated highly with one another (P < or = 0.01) and with Ishak stages of fibrosis. Among the serum markers, HA was effective in discriminating between Ishak stages 0-1 and Ishak stages 2-3 compared with FS-II, with an area under the curve of 0.76 versus 0.66 and a false-positive rate of 0.33 versus 0.67, respectively. All three serum markers predicted advanced fibrosis and cirrhosis. YKL-40 had the highest false-positive rates in all categories of fibrosis. CONCLUSIONS: HA can be utilized as a reliable surrogate marker in distinguishing three clinically relevant stages of fibrosis: absent/minimal, intermediate, and advanced/cirrhosis. HA should be considered as a cost-effective alternative to other serum markers for staging fibrosis and for determining the timing and selection of HCV treatment.


Assuntos
Proteínas da Matriz Extracelular/sangue , Glicoproteínas/sangue , Hepatite C Crônica/sangue , Ácido Hialurônico/sangue , Cirrose Hepática/sangue , Adipocinas , Adulto , Idoso , Biomarcadores/sangue , Biópsia , Proteína 1 Semelhante à Quitinase-3 , Feminino , Hepatite C Crônica/patologia , Humanos , Lectinas , Masculino , Pessoa de Meia-Idade , Curva ROC , Estudos Retrospectivos , Sensibilidade e Especificidade
20.
Am J Surg Pathol ; 31(8): 1191-5, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17667542

RESUMO

Morphologic, clinical, and genetic evidence suggests that pancreatic intraepithelial neoplasia (PanIN) is a precursor to ductal adenocarcinoma. But understanding precursor lesions in a pancreas with existing tumor is hampered by the fact that chronic pancreatitis often accompanies carcinoma, and the possible interactions between tumor, chronic pancreatitis, and PanIN are complex. Furthermore, cancerization of ducts can mimic high-grade PanIN. Heterotopic pancreas has a genetic make-up, physiologic function, and local environmental exposure similar to that of the pancreas. It offers an opportunity to study putative precursor lesions in a setting with fewer confounding factors. We identified 6 pancreatic cancer patients who had heterotopic pancreas removed at the time of surgery. All 6 cases were immunostained for p53, cyclin D1, and p16. Molecular analysis of K-ras mutation was also done. All 6 cancer-associated heterotopias had PanIN-1A or 1B; 5 had PanIN-2 and 1 had PanIN-3. Three of 6 cases harbored the same K-ras codon 12 mutation as the PanINs in orthotopic pancreas, and a similar pattern of p53, cyclin D1, and p16 expression was observed between heterotopic and orthotopic pancreas in all 6 cases. There was no chronic pancreatitis in the cancer-associated heterotopias, but chronic pancreatitis was seen adjacent to carcinoma in 5 of 6 cases. The presence of PanIN in heterotopic pancreas from patients with ductal adenocarcinoma supports the progression model.


Assuntos
Carcinoma in Situ/patologia , Carcinoma Ductal Pancreático/patologia , Coristoma/patologia , Duodenopatias/patologia , Pâncreas , Neoplasias Pancreáticas/patologia , Gastropatias/patologia , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/metabolismo , Carcinoma in Situ/genética , Carcinoma in Situ/metabolismo , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Coristoma/genética , Coristoma/metabolismo , DNA de Neoplasias/análise , Progressão da Doença , Duodenopatias/genética , Duodenopatias/metabolismo , Feminino , Genes ras , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Mutação , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Lesões Pré-Cancerosas , Gastropatias/genética , Gastropatias/metabolismo
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