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1.
J Clin Oncol ; 42(7): 790-799, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38175991

RESUMO

PURPOSE: There are limited data on antiviral treatment utilization and its impact on long-term outcomes of hepatitis B virus (HBV)- and hepatitis C virus (HCV)-related hepatocellular carcinoma (HCC) after hepatic resection. We aimed to determine the utilization and impact of antivirals in HBV- and HCV-related HCC. METHODS: This cohort study included 1,906 participants (1,054 HBV-related HCC and 852 HCV-related HCC) from 12 international sites. All participants had HBV- or HCV-related HCC and underwent curative surgical resection. The primary outcome was the utilization of antiviral therapy, and the secondary outcome was long-term overall survival (OS). RESULTS: The mean (±standard deviation [SD]) age was 62.1 (±11.3) years, 74% were male, and 84% were Asian. A total of 47% of the total cohort received antiviral therapy during a mean (±SD) follow-up of 5.0 (±4.3) years. The overall antiviral utilization for participants with HBV-related HCC was 57% and declined over time, from 65% before 2010, to 60% from 2010 to 2015, to 47% beyond 2015, P < .0001. The overall utilization of antivirals for HCV-related HCC was 35% and increased over time, from 24% before 2015 to 74% from 2015 and beyond, P < .0001. The 10-year OS was lower in untreated participants for both HBV (58% v 61%) and HCV participants (38% v 82%; both P < .0001). On multivariable Cox regression analysis adjusted for relevant confounders, antiviral therapy initiated before or within 6 months of HCC diagnosis was independently associated with lower mortality in both HBV- (adjusted hazard ratio [aHR], 0.60 [95% CI, 0.43 to 0.83]; P = .002) and HCV-related HCC (aHR, 0.18 [95% CI, 0.11 to 0.31]; P < .0001). CONCLUSION: Antiviral therapy is associated with long-term survival in people with HBV- or HCV-related HCC who undergo curative resection but is severely underutilized.


Assuntos
Carcinoma Hepatocelular , Hepatite B , Hepatite C , Neoplasias Hepáticas , Masculino , Humanos , Pessoa de Meia-Idade , Idoso , Feminino , Carcinoma Hepatocelular/patologia , Vírus da Hepatite B , Neoplasias Hepáticas/patologia , Hepacivirus , Estudos de Coortes , Hepatite C/complicações , Hepatite C/tratamento farmacológico , Antivirais/uso terapêutico , Hepatite B/complicações , Hepatite B/tratamento farmacológico , Estudos Retrospectivos
2.
Biosensors (Basel) ; 13(7)2023 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-37504074

RESUMO

To overcome early cancer detection challenges, diagnostic tools enabling more sensitive, rapid, and noninvasive detection are necessary. An attractive cancer target for diagnostic blood tests is human Ecto-NOX disulfide-thiol exchanger 2 (ENOX2), expressed in most human cancer types and regularly shed into blood sera. Here, we developed an electrochemical DNA-based (E-DNA) biosensor that rapidly detects physiologically relevant levels of ENOX2. To identify ENOX2-binding aptamers that could potentially be used in a biosensor, recombinantly expressed ENOX2 was used as a binding target in an oligonucleotide library pull-down that generated a highly enriched ENOX2-binding aptamer. This candidate aptamer sensitively bound ENOX2 via gel mobility shift assays. To enable this aptamer to function in an ENOX2 E-DNA biosensor, the aptamer sequence was modified to adopt two conformations, one capable of ENOX2 binding, and one with disrupted ENOX2 binding. Upon ENOX2 introduction, a conformational shift to the ENOX2 binding state resulted in changed dynamics of a redox reporter molecule, which generated a rapid, significant, and target-specific electrical current readout change. ENOX2 biosensor sensitivity was at or below the diagnostic range. The ENOX2 E-DNA biosensor design presented here may enable the development of more sensitive, rapid, diagnostic tools for early cancer detection.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Neoplasias , Humanos , Biomarcadores Tumorais , Aptâmeros de Nucleotídeos/química , DNA/química , Técnicas Biossensoriais/métodos , Pulmão
3.
Mol Oncol ; 14(10): 2358-2374, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33245585

RESUMO

Telomerase reverse transcriptase (TERT) is pathologically expressed in the vast majority of human cancers, but the epigenetic regulation of its expression is only beginning to be understood. In particular, the active TERT gene in cancer cells has been characterized as having a hypermethylated CpG island, opposite to the general association of DNA methylation with gene repression. Here, we analyzed TERT promoter CpG methylation in 833 human cancer cell lines representing 23 different tissue types and found hypermethylation of the upstream portion of the CpG island and more conserved hypomethylation of a region including the proximal TERT promoter and exon 1. In cell lines with monoallelic expression of TERT, we found allelic methylation of the proximal TERT promoter. This included cell lines with the -124 or -146 activating promoter mutation as well as wild-type TERT cancer lines. In these cell line types, decreased proximal promoter methylation is associated with the active allele. Compared to cells with monoallelic expression of TERT, lines with biallelic expression of TERT had even lower methylation in the proximal TERT promoter. Thus, in cell lines from cancers of many different tissues, the TERT proximal promoter has canonical DNA methylation, with low methylation correlating with increased TERT expression.


Assuntos
Alelos , Metilação de DNA/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias/enzimologia , Neoplasias/genética , Regiões Promotoras Genéticas , Telomerase/genética , Sequência de Bases , Linhagem Celular Tumoral , Éxons/genética , Código das Histonas , Humanos , Polimorfismo de Nucleotídeo Único/genética , Transcrição Gênica
4.
Nat Commun ; 10(1): 3350, 2019 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-31350390

RESUMO

The liver parenchyma is composed of hepatocytes and bile duct epithelial cells (BECs). Controversy exists regarding the cellular origin of human liver parenchymal tissue generation during embryonic development, homeostasis or repair. Here we report the existence of a hepatobiliary hybrid progenitor (HHyP) population in human foetal liver using single-cell RNA sequencing. HHyPs are anatomically restricted to the ductal plate of foetal liver and maintain a transcriptional profile distinct from foetal hepatocytes, mature hepatocytes and mature BECs. In addition, molecular heterogeneity within the EpCAM+ population of freshly isolated foetal and adult human liver identifies diverse gene expression signatures of hepatic and biliary lineage potential. Finally, we FACS isolate foetal HHyPs and confirm their hybrid progenitor phenotype in vivo. Our study suggests that hepatobiliary progenitor cells previously identified in mice also exist in humans, and can be distinguished from other parenchymal populations, including mature BECs, by distinct gene expression profiles.


Assuntos
Fígado/citologia , Transcrição Gênica , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/metabolismo , Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular/metabolismo , Molécula de Adesão da Célula Epitelial/genética , Molécula de Adesão da Célula Epitelial/metabolismo , Feto/metabolismo , Hepatócitos/citologia , Hepatócitos/metabolismo , Humanos , Fígado/metabolismo , Análise de Célula Única , Células-Tronco/citologia , Células-Tronco/metabolismo
5.
Tuberculosis (Edinb) ; 115: 96-107, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30948183

RESUMO

All mycobacteria, including nontuberculous mycobacteria (NTM), synthesize an array of lipids including phosphatidylinositol mannosides (PIM), lipomannan (LM), and lipoarabinomannan (LAM). While absent from Mycobacterium tuberculosis (M. tb), glycopeptidolipids (GPL) are critical to the biology of NTM. M. tb and some NTM also synthesize trehalose-containing glycolipids and phenolic glycolipids (PGL), key membrane constituents with essential roles in metabolism. While lipids facilitate immune evasion, they also induce host immunity against tuberculosis. However, much less is known about the significance of NTM-derived PIM, LM, LAM, GPL, trehalose-containing glycolipids, and PGL as virulence factors, warranting further investigation. While culling the scientific literature on NTM lipids, it's evident that such studies were relatively few in number with the overwhelming majority of prior work dedicated to understanding lipids from the saprophyte Mycobacterium smegmatis. The identification and functional analysis of immune reactive NTM-derived lipids remain challenging, but such work is likely to yield a greater understanding of the pathogenesis of NTM lung disease. In this review, we juxtapose the vast literature of what is currently known regarding M. tb lipids to the lesser number of studies for comparable NTM lipids. But because GPL is the most widely recognized NTM lipid, we highlight its role in disease pathogenesis.


Assuntos
Lipídeos/biossíntese , Mycobacterium tuberculosis/metabolismo , Bacillus/metabolismo , Parede Celular/imunologia , Parede Celular/fisiologia , Imunidade Celular/fisiologia , Lipídeos/química , Lipídeos/imunologia , Mycobacterium tuberculosis/imunologia , Micobactérias não Tuberculosas/imunologia , Micobactérias não Tuberculosas/metabolismo
6.
Pediatr Surg Int ; 34(1): 113-116, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29170900

RESUMO

We present the case of a 14-year-old male with a history of small bowel transplantation for long segment Hirschsprung's disease who underwent Duhamel ileorectal pull-through procedure. In post-transplant, the patient had no restrictions and was not TPN-dependent. To improve his quality of life, he and his family were interested in closing the ileostomy and undergoing pull-through surgery. The complexity of the case includes the presence of an aganglionic rectal segment-a short root of the mesentery due to the small bowel transplant-and significant immunosuppression. At the moment, he is continent, doing well, and has not had any remarkable complications.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório , Doença de Hirschsprung/cirurgia , Ileostomia , Intestino Delgado/transplante , Adolescente , Humanos , Imunossupressores/uso terapêutico , Masculino
7.
Nucleic Acids Res ; 41(2): 754-63, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23180800

RESUMO

The DNA-binding specificity and affinity of the dimeric human transcription factor (TF) STAT1, were assessed by total internal reflectance fluorescence protein-binding microarrays (TIRF-PBM) to evaluate the effects of protein phosphorylation, higher-order polymerization and small-molecule inhibition. Active, phosphorylated STAT1 showed binding preferences consistent with prior characterization, whereas unphosphorylated STAT1 showed a weak-binding preference for one-half of the GAS consensus site, consistent with recent models of STAT1 structure and function in response to phosphorylation. This altered-binding preference was further tested by use of the inhibitor LLL3, which we show to disrupt STAT1 binding in a sequence-dependent fashion. To determine if this sequence-dependence is specific to STAT1 and not a general feature of human TF biology, the TF Myc/Max was analysed and tested with the inhibitor Mycro3. Myc/Max inhibition by Mycro3 is sequence independent, suggesting that the sequence-dependent inhibition of STAT1 may be specific to this system and a useful target for future inhibitor design.


Assuntos
DNA/metabolismo , Fator de Transcrição STAT1/metabolismo , Sequência de Bases , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , DNA/química , Fosforilação , Multimerização Proteica , Proteínas Proto-Oncogênicas c-myc/metabolismo , Proteínas Repressoras/metabolismo , Fator de Transcrição STAT1/antagonistas & inibidores , Fator de Transcrição STAT1/química
8.
Pediatr Transplant ; 16(4): 373-8, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22463739

RESUMO

The most common indication for pediatric LTx is biliary atresia with failed HPE, yet the effect of previous HPE on the outcome after LTx has not been well characterized. We retrospectively reviewed a single-center experience with 134 consecutive pediatric liver transplants for the treatment of biliary atresia from 1 May 1995 to 28 April 2008. Of 134 patients, 22 underwent LTx without prior HPE (NPE), while 112 patients underwent HPE first. HPE patients were grouped into EF, defined as need for LTx within the first year of life, and LF, defined as need for LTx beyond the first year of life. NPE and EF groups differed significantly from the LF group in age, weight, PELD, and ICU status (p < 0.05) with NPE having the highest PELD and ICU status. Patients who underwent salvage LTx after EF following HPE had a significantly higher incidence of post-operative bacteremia and septicemia (p < 0.05), and subsequently lower survival rates. One-year patient survival and graft survival were as follows: NPE 100%, EF 81%, and LF 96% (p < 0.05); and NPE 96%, EF 79%, and LF 96% (p < 0.05). Further investigation into the optimal treatment of biliary atresia should focus on identifying patients at high risk of EF who may benefit from proceeding directly to LTx given the increased risk of post-LTx bacteremia, sepsis, and death after failed HPE.


Assuntos
Atresia Biliar/cirurgia , Transplante de Fígado , Portoenterostomia Hepática , Adolescente , Atresia Biliar/mortalidade , Criança , Pré-Escolar , Sobrevivência de Enxerto , Humanos , Lactente , Recém-Nascido , Transplante de Fígado/mortalidade , Complicações Pós-Operatórias/epidemiologia , Reoperação , Estudos Retrospectivos , Sepse/epidemiologia , Sepse/etiologia , Infecção da Ferida Cirúrgica/epidemiologia , Taxa de Sobrevida , Falha de Tratamento , Resultado do Tratamento
9.
PLoS One ; 6(9): e23783, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21931613

RESUMO

Although potentiostats are the foundation of modern electrochemical research, they have seen relatively little application in resource poor settings, such as undergraduate laboratory courses and the developing world. One reason for the low penetration of potentiostats is their cost, as even the least expensive commercially available laboratory potentiostats sell for more than one thousand dollars. An inexpensive electrochemical workstation could thus prove useful in educational labs, and increase access to electrochemistry-based analytical techniques for food, drug and environmental monitoring. With these motivations in mind, we describe here the CheapStat, an inexpensive (<$80), open-source (software and hardware), hand-held potentiostat that can be constructed by anyone who is proficient at assembling circuits. This device supports a number of potential waveforms necessary to perform cyclic, square wave, linear sweep and anodic stripping voltammetry. As we demonstrate, it is suitable for a wide range of applications ranging from food- and drug-quality testing to environmental monitoring, rapid DNA detection, and educational exercises. The device's schematics, parts lists, circuit board layout files, sample experiments, and detailed assembly instructions are available in the supporting information and are released under an open hardware license.


Assuntos
Técnicas de Química Analítica/economia , Técnicas de Química Analítica/instrumentação , Educação/economia , Equipamentos e Provisões Elétricas/economia , Eletroquímica/economia , Eletroquímica/instrumentação , Técnicas Biossensoriais/economia , DNA/análise , DNA/genética , Países em Desenvolvimento/economia , Laboratórios/economia , Reação em Cadeia da Polimerase , Universidades/economia
10.
J Vis Exp ; (52)2011 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-21673639

RESUMO

As medicine is currently practiced, doctors send specimens to a central laboratory for testing and thus must wait hours or days to receive the results. Many patients would be better served by rapid, bedside tests. To this end our laboratory and others have developed a versatile, reagentless biosensor platform that supports the quantitative, reagentless, electrochemical detection of nucleic acids (DNA, RNA), proteins (including antibodies) and small molecules analytes directly in unprocessed clinical and environmental samples. In this video, we demonstrate the preparation and use of several biosensors in this "E-DNA" class. In particular, we fabricate and demonstrate sensors for the detection of a target DNA sequence in a polymerase chain reaction mixture, an HIV-specific antibody and the drug cocaine. The preparation procedure requires only three hours of hands-on effort followed by an overnight incubation, and their use requires only minutes.


Assuntos
Anticorpos/análise , Técnicas Biossensoriais/métodos , DNA/análise , Técnicas Eletroquímicas/métodos , Proteínas/análise , RNA/análise , Anticorpos Antivirais/análise , Técnicas Biossensoriais/instrumentação , Cocaína/análise , Técnicas Eletroquímicas/instrumentação , HIV/imunologia
11.
Stem Cells Dev ; 19(8): 1231-40, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19811096

RESUMO

Human induced pluripotent stem cells (iPSCs) hold promise as a source of adult-derived, patient-specific pluripotent cells for use in cell-based regenerative therapies. However, current methods of cell culture are tedious and expensive, and the mechanisms underlying cell proliferation are not understood. In this study, we investigated expression and function of iPSC integrin extracellular matrix receptors to better understand the molecular mechanisms of cell adhesion, survival, and proliferation. We show that iPSC lines generated using Oct-3/4, Sox-2, Nanog, and Lin-28 express a repertoire of integrins similar to that of hESCs, with prominent expression of subunits alpha5, alpha6, alphav, beta1, and beta5. Integrin function was investigated in iPSCs cultured without feeder layers on Matrigel or vitronectin, in comparison to human embryonic stem cells. beta1 integrins were required for adhesion and proliferation on Matrigel, as shown by immunological blockade experiments. On vitronectin, the integrin alphavbeta5 was required for initial attachment, but inhibition of both alphavbeta5 and beta1 was required to significantly decrease iPSC proliferation. Furthermore, iPSCs cultured on vitronectin for 9 passages retained normal karyotype, pluripotency marker expression, and capacity to differentiate in vitro. These studies suggest that vitronectin, or derivatives thereof, might substitute for Matrigel in a more defined system for iPSC culture.


Assuntos
Proliferação de Células , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Integrinas/metabolismo , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/farmacologia , Antígenos de Diferenciação/metabolismo , Adesão Celular/efeitos dos fármacos , Adesão Celular/fisiologia , Técnicas de Cultura de Células , Diferenciação Celular/fisiologia , Linhagem Celular , Colágeno/metabolismo , Combinação de Medicamentos , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/metabolismo , Humanos , Integrina beta1/imunologia , Integrina beta1/metabolismo , Integrinas/genética , Cariotipagem , Laminina/metabolismo , Proteoglicanas/metabolismo , Receptores de Vitronectina/imunologia , Receptores de Vitronectina/metabolismo , Vitronectina/metabolismo
12.
Hepatology ; 37(4): 871-9, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12668980

RESUMO

A total of 103 cases of hepatocellular carcinoma (HCC) arising in native livers discovered at the time of transplantation underwent allelic loss analysis. HCC mutational allelotyping targeted 10 genomic loci (1p, 3p, 5q, 7q, 8q, 9p, 10q, 17p, 17q, 18q) using 18 polymorphic microsatellite markers situated in proximity to known tumor suppressor genes associated with human carcinogenesis. Gene analysis was performed on microdissected tissue samples removed from 4-microm thick histologic sections at specific topographic sites selected on the basis of representative cellular characteristics. Microdissection targets included largest tumor nodule at 2 locations as well as up to 3 additional tumor nodules in each case. HCC genotyping characteristics including mutational profile and cumulative fractional allelic loss (FAL) were correlated with clinical and pathologic features. Individual nodules of HCC showed 2 patterns of mutational change: (1) essentially concordant mutational profiles consistent with intrahepatic spread of tumor, or (2) discordant mutational profiles consistent with independent primary cancer formation. In 15 of 56 cases (27%) in which the HCC was in a multinodular, bilobar form (T4), sufficient discordance in the allelic loss profile enabled a more accurate T-stage classification with better prediction of recurrence-free survival. In conclusion, microdissection genotyping of HCC is an effective and objective means to (1) distinguish between de novo HCC tumor formation versus intrahepatic spread of cancer and to (2) improve on current methods for prediction of tumor aggressiveness and recurrence-free survival after liver transplantation.


Assuntos
Alelos , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/secundário , Dissecação , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/secundário , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/cirurgia , Diagnóstico Diferencial , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/cirurgia , Repetições de Microssatélites , Mutação , Recidiva Local de Neoplasia , Análise de Sobrevida
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