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1.
Ann Hepatol ; 17(5): 871-879, 2018 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-30145563

RESUMO

INTRODUCTION AND AIM: We sought to identify independent risk factors for cirrhosis in HFE p.C282Y homozygotes in a cross-sectional study. MATERIAL AND METHODS: We evaluated 368 p.C282Y homozygotes who underwent liver biopsy and compared characteristics of those with and without cirrhosis. We performed multivariable logistic regression on cirrhosis with: age; sex; race/ethnicity; diabetes; blood pints/units donated voluntarily; erythrocyte pints/units received; iron supplement use; alcohol intake, g/d; body mass index, kg/m2; swollen/tender 2nd/3rd metacarpophalangeal joints; elevated alanine aminotransferase; elevated aspartate aminotransferase; steatosis/fatty liver; iron removed by phlebotomy, g; and GNPAT p.D519G positivity. RESULTS: Mean age of 368 participants (73.6% men) was 47 ± 13 (standard deviation) y. Cirrhosis was diagnosed in 86 participants (23.4%). Participants with cirrhosis had significantly greater mean age, proportion of men, diabetes prevalence, mean daily alcohol intake, prevalence of swollen/ tender 2nd/3rd metacarpophalangeal joints, mean serum ferritin, elevated alanine aminotransferase, elevated aspartate aminotransferase, and mean iron removed; and significantly fewer mean blood pints/units donated. GNPAT p.D519G positivity was detected in 82 of 188 participants (43.6%). In a multivariable model for cirrhosis, there were four significant positive associations: age (10-y intervals) (odds ratio 2.2 [95% confidence interval 1.5, 3.3]); diabetes (3.3; [1.1, 9.7]); alcohol intake (14 g alcohol drinks/d) (1.5 [1.2, 1.8]); and iron removed, g (1.3 [1.2, 1.4]). There was no statistical evidence of two-way interactions between these variables. CONCLUSION: In conclusion, cirrhosis in HFE p.C282Y homozygotes is significantly associated with age, diabetes, daily alcohol intake, and iron removed by phlebotomy, taking into account the effect of other variables.


Assuntos
Proteína da Hemocromatose/genética , Hemocromatose/genética , Homozigoto , Cirrose Hepática/genética , Mutação , Aciltransferases/genética , Adulto , Fatores Etários , Consumo de Bebidas Alcoólicas/efeitos adversos , Consumo de Bebidas Alcoólicas/epidemiologia , Austrália/epidemiologia , Comorbidade , Estudos Transversais , Diabetes Mellitus/epidemiologia , Feminino , Predisposição Genética para Doença , Hemocromatose/diagnóstico , Hemocromatose/epidemiologia , Hemocromatose/terapia , Humanos , Cirrose Hepática/epidemiologia , Cirrose Hepática/patologia , Masculino , Pessoa de Meia-Idade , Fenótipo , Flebotomia , Polimorfismo de Nucleotídeo Único , Prevalência , Medição de Risco , Fatores de Risco , Estados Unidos/epidemiologia
2.
Blood Cells Mol Dis ; 63: 15-20, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27936396

RESUMO

BACKGROUND: GNPAT p.D519G positivity is significantly increased in HFE p.C282Y homozygotes with markedly increased iron stores. We sought to determine associations of p.D519G and iron-related variables with iron stores in p.C282Y homozygotes. METHODS: We defined markedly increased iron stores as serum ferritin >2247pmol/L (>1000µg/L) and either hepatic iron >236µmol/g dry weight or iron >10g by induction phlebotomy (men and women). We defined normal or mildly elevated iron stores as serum ferritin <674.1pmol/L (<300µg/L) or either age≥40y with iron ≤2.5g iron by induction phlebotomy or age≥50y with ≤3.0g iron by induction phlebotomy (men only). We compared participant subgroups using univariate methods. Using multivariable logistic regression, we evaluated associations of markedly increased iron stores with these variables: age; iron supplement use (dichotomous); whole blood units donated; erythrocyte units received as transfusion; daily alcohol consumption, g; and p.D519G positivity (heterozygosity or homozygosity). RESULTS: The mean age of 56 participants (94.6% men) was 55±10 (SD) y; 41 had markedly increased iron stores. Prevalences of swollen/tender 2nd/3rd metacarpophalangeal joints and elevated aspartate or alanine aminotransferase were significantly greater in participants with markedly increased iron stores. Only participants with markedly increased iron stores had cirrhosis. In multivariable analyses, p.D519G positivity was the only exposure variable significantly associated with markedly increased iron stores (odds ratio 9.9, 95% CI [1.6, 60.3], p=0.0126). CONCLUSIONS: GNPAT p.D519G is strongly associated with markedly increased iron stores in p.C282Y homozygotes after correction for age, iron-related variables, and alcohol consumption.


Assuntos
Aciltransferases/genética , Proteína da Hemocromatose/genética , Ferro/metabolismo , Mutação de Sentido Incorreto , Aciltransferases/metabolismo , Adulto , Fatores Etários , Idoso , Consumo de Bebidas Alcoólicas , Feminino , Proteína da Hemocromatose/metabolismo , Homozigoto , Humanos , Masculino , Pessoa de Meia-Idade
3.
PLoS One ; 9(10): e108483, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25310185

RESUMO

PURPOSE: Colon cancers deficient in mismatch repair (MMR) may exhibit diminished expression of the DNA repair gene, MRE11, as a consequence of contraction of a T11 mononucleotide tract. This study investigated MRE11 status and its association with prognosis, survival and drug response in patients with stage III colon cancer. PATIENTS AND METHODS: Cancer and Leukemia Group B 89803 (Alliance) randomly assigned 1,264 patients with stage III colon cancer to postoperative weekly adjuvant bolus 5-fluorouracil/leucovorin (FU/LV) or irinotecan+FU/LV (IFL), with 8 year follow-up. Tumors from these patients were analyzed to determine stability of a T11 tract in the MRE11 gene. The primary endpoint was overall survival (OS), and a secondary endpoint was disease-free survival (DFS). Non-proportional hazards were addressed using time-dependent covariates in Cox analyses. RESULTS: Of 625 tumor cases examined, 70 (11.2%) exhibited contraction at the T11 tract in one or both MRE11 alleles and were thus predicted to be deficient in MRE11 (dMRE11). In pooled treatment analyses, dMRE11 patients showed initially reduced DFS and OS but improved long-term DFS and OS compared with patients with an intact MRE11 T11 tract. In the subgroup of dMRE11 patients treated with IFL, an unexplained early increase in mortality but better long-term DFS than IFL-treated pMRE11 patients was observed. CONCLUSIONS: Analysis of this relatively small number of patients and events showed that the dMRE11 marker predicts better prognosis independent of treatment in the long-term. In subgroup analyses, dMRE11 patients treated with irinotecan exhibited unexplained short-term mortality. MRE11 status is readily assayed and may therefore prove to be a useful prognostic marker, provided that the results reported here for a relatively small number of patients can be generalized in independent analyses of larger numbers of samples. TRIAL REGISTRATION: ClinicalTrials.gov NCT00003835.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias do Colo/genética , Neoplasias do Colo/mortalidade , Proteínas de Ligação a DNA/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Camptotecina/administração & dosagem , Camptotecina/análogos & derivados , Camptotecina/uso terapêutico , Neoplasias do Colo/tratamento farmacológico , Proteínas de Ligação a DNA/metabolismo , Intervalo Livre de Doença , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/uso terapêutico , Seguimentos , Estudos de Associação Genética , Humanos , Irinotecano , Leucovorina/administração & dosagem , Leucovorina/uso terapêutico , Proteína Homóloga a MRE11 , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Prognóstico , Resultado do Tratamento , Adulto Jovem
4.
Gastroenterology ; 147(3): 637-45, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24859205

RESUMO

BACKGROUND & AIMS: The CpG island methylator phenotype (CIMP), defined by a high frequency of aberrantly methylated genes, is a characteristic of a subclass of colon tumors with distinct clinical and molecular features. Cohort studies have produced conflicting results on responses of CIMP-positive tumors to chemotherapy. We assessed the association between tumor CIMP status and survival of patients receiving adjuvant fluorouracil and leucovorin alone or with irinotecan (IFL). METHODS: We analyzed data from patients with stage III colon adenocarcinoma randomly assigned to groups given fluorouracil and leucovorin or IFL after surgery, from April 1999 through April 2001. The primary end point of the trial was overall survival and the secondary end point was disease-free survival. DNA isolated from available tumor samples (n = 615) was used to determine CIMP status based on methylation patterns at the CACNA1G, IGF2, NEUROG1, RUNX3, and SOCS1 loci. The effects of CIMP on survival were modeled using Kaplan-Meier and Cox proportional hazards; interactions with treatment and BRAF, KRAS, and mismatch repair (MMR) status were also investigated. RESULTS: Of the tumor samples characterized for CIMP status, 145 were CIMP positive (23%). Patients with CIMP-positive tumors had shorter overall survival times than patients with CIMP-negative tumors (hazard ratio = 1.36; 95% confidence interval: 1.01-1.84). Treatment with IFL showed a trend toward increased overall survival for patients with CIMP-positive tumors, compared with treatment with fluorouracil and leucovorin (hazard ratio = 0.62; 95% CI: 0.37-1.05; P = .07), but not for patients with CIMP-negative tumors (hazard ratio = 1.38; 95% CI: 1.00-1.89; P = .049). In a 3-way interaction analysis, patients with CIMP-positive, MMR-intact tumors benefited most from the addition of irinotecan to fluorouracil and leucovorin therapy (for the interaction, P = .01). CIMP was more strongly associated with response to IFL than MMR status. Results for disease-free survival times were comparable among all analyses. CONCLUSIONS: Patients with stage III, CIMP-positive, MMR-intact colon tumors have longer survival times when irinotecan is added to combination therapy with fluorouracil and leucovorin.


Assuntos
Adenocarcinoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias do Colo/tratamento farmacológico , Ilhas de CpG , Metilação de DNA , Adenocarcinoma/genética , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Camptotecina/administração & dosagem , Camptotecina/análogos & derivados , Quimioterapia Adjuvante , Colectomia , Neoplasias do Colo/genética , Neoplasias do Colo/mortalidade , Neoplasias do Colo/patologia , Reparo de Erro de Pareamento de DNA , Intervalo Livre de Doença , Feminino , Fluoruracila/administração & dosagem , Humanos , Irinotecano , Estimativa de Kaplan-Meier , Leucovorina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Fenótipo , Modelos de Riscos Proporcionais , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
5.
Physiol Genomics ; 43(16): 974-80, 2011 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-21693618

RESUMO

Within the field of forensic pathology, determination of the cause of death depends upon identifying physical changes in the corpse or finding diagnostic laboratory abnormalities. When such perturbations are absent, definitive assignment of a cause of death may be difficult or impossible. An example of such a problem is sudden infant death syndrome (SIDS), a common cause of neonatal mortality that does not produce physical findings or laboratory abnormalities. Although respiratory failure as a cause of SIDS represents the most widely held hypothesis, sudden cardiac death and hyperthermia have also been advanced as possible causes. We hypothesize that each of these physiological stresses would produce a different pattern of premortem gene expression and that these patterns of gene expression would remain evident in tissues collected postmortem. If these patterns were sufficiently distinctive, they could be used to identify the cause of death. Using an infant mouse model, we compared gene expression patterns in liver tissue after sudden death, lethal hyperthermia, and lethal hypoxia. Each of these conditions produced readily distinguishable differences in gene expression patterns. With the K-nearest neighbor classification algorithm, only 10 genes are necessary to correctly classify samples. If the liver tissue was not harvested immediately after death, additional alteration in gene expression patterns resulted; however, these alterations did not affect the group of genes used to classify the samples. Our findings suggest that gene expression analysis from tissues collected postmortem may provide useful clues about certain physiologic stresses that may precede death.


Assuntos
Morte Súbita/etiologia , Animais , Western Blotting , Causas de Morte , Feminino , Regulação da Expressão Gênica/genética , Regulação da Expressão Gênica/fisiologia , Hipertermia Induzida/efeitos adversos , Hipóxia/genética , Masculino , Camundongos
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