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1.
Int J Mol Sci ; 24(13)2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37446098

RESUMO

Glypican-3 (GPC-3) is a heparin sulfate proteoglycan located extracellularly and anchored to the cell membrane of transformed hepatocytes. GPC-3 is not expressed in normal or cirrhotic liver tissue but is overexpressed in hepatocellular carcinoma (HCC). Because of this, GPC-3 is one of the most important emerging immunotargets for treatment and as an early detection marker of HCC. To determine if GPC-3 domains associated with serum small extracellular vesicles (sEVs) could be used as an HCC diagnostic marker, we predicted in silico GPC-3 structural properties and tested for the presence of its full-length form and/or cleaved domains in serum sEVs isolated from patients with HCC. Structural analysis revealed that the Furin cleavage site of GPC-3 is exposed and readily accessible, suggesting the facilitation of GPC-3 cleavage events. Upon isolation of sEVs from both hepatocytes, culture media and serum of patients with HCC were studied for GPC-3 content. This data suggests that Furin-dependent GPC-3 cleaved domains could be a powerful tool for detection of initial stages of HCC and serve as a predictor for disease prognosis.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Furina , Glipicanas/metabolismo , Biomarcadores Tumorais/metabolismo
2.
Cancers (Basel) ; 15(12)2023 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-37370754

RESUMO

Immunosuppressive drugs (IMD) are widely utilized to treat many autoimmune conditions and to prevent rejection in organ transplantation. Cancer has been associated with prolonged use of IMD in transplant patients. However, no detailed, systematic analysis of the risk of cancer has been performed in patients receiving IMD for any condition and duration. We analyzed Medicare data from Texas Medicare beneficiaries, regardless of their age, between 2007 and 2018, from the Texas Cancer Registry. We analyzed the data for the risk of cancer after IMD use associated with demographic characteristics, clinical conditions, and subsequent cancer type. Of 29,196 patients who used IMD for a variety of indications, 5684 developed cancer. The risk of cancer (standardized incidence ratio) was particularly high for liver (9.10), skin (7.95), lymphoma (4.89), and kidney (4.39). Patients receiving IMD had a four fold greater likelihood of developing cancer than the general population. This risk was higher within the first 3 years of IMD utilization and in patients younger than 65 years and minorities. This study shows that patients receiving IMD for any indications have a significantly increased risk of cancer, even with short-term use. Caution is needed for IMD use; in addition, an aggressive neoplastic diagnostic screening is warranted.

3.
Int J Angiol ; 32(2): 128-130, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37207015

RESUMO

Organ transplantation can be associated with vascular torsions and angulations of both recipient and donor vessels. Such kinks and/or torsions of vessels can compromise the vascular integrity, obstruct inflow and/or outflow, and result in loss of the organ and/or body parts. On many occasions, mild angulations and torsions can be successfully addressed by repositioning the organ. In cases where the abnormal findings persist, maneuvers such as placing a fat pad to create a smoother curve, or even opening the peritoneum (in the case of kidney transplants) to allow for a better positioning of the organ, are associated with successful outcomes. When such torsions/angulations persist despite these approaches, further innovative tactics are required. In the current report, we propose a technique that involves longitudinally opening of a synthetic graft that is rigid enough to maintain its shape, such as a ringed polytetrafluoroethylene graft, and placing it as an external stent around the angulated/torsioned vessel. This maneuver will correct the underlying vascular compromise without having to perform any further invasive interventions, such as reimplanting the organ or resecting part of the involved vessel. Although primarily illustrated for application by describing an instance in which exostenting was applied during kidney transplantation, our approach could be applied to any vessel under many circumstances where angulations/twists are encountered. In this report, we describe the use of an external stent, also called exostenting, to correct a severe torsion/angulation of the external iliac artery in a kidney transplant recipient where all other measures were unsuccessful.

5.
Cell Oncol (Dordr) ; 41(2): 169-184, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29204978

RESUMO

BACKGROUND: Recently, Glypican-3 (GPC3) has been identified as a potential hepatocellular carcinoma (HCC) diagnostic and/or therapeutic target. GPC3 has been found to be up-regulated in HCC and to be absent in normal and cirrhotic liver. As yet, however, the molecular characteristics of GPC3 and its role in HCC cell physiology and development are still undefined. METHODS: Human hepatocyte cultures were established from 10 HCC patients. Additional liver samples were obtained from 5 patients without cirrhosis and/or HCC. Soft agar colony formation, (co-)immunofluorescence and Western blot assays were used to characterize the hapatocyte cultures. The expression of GPC3 in the hepatocytes was silenced using siRNA, after which, apoptosis, scratch wound migration and transwell invasion assays were performed. RESULTS: We found that in HCC precursor hepatocytes GPC3 is increasingly expressed in different forms and at different locations, i.e., a non-cleaved form (70 kDa) was found to be localized in the cytoplasm while a N-terminal cleaved form (N-GPC3: 40 kDa) was fond to be localized in the cytoplasm and at the extracellular side of hepatocyte membranes. In addition, we found that the non-cleaved form of GPC3 co-localizes with Furin-Convertase in the Golgi apparatus. We also found that, similar to GPC3, Furin-Convertase is expressed in HCC precursor cells, suggesting a role in GPC3 processing. Subsequent siRNA-mediated GPC3 silencing resulted in a temporary inhibition of cell proliferation, migration and ivasion, while inducing apoptosis in transformed hepatocytes. CONCLUSION: Our data reveal new aspects of the role of GPC3 in early hepatocyte transformation. In addition we conclude that GPC3 may serve as a new HCC immune-therapeutic target.


Assuntos
Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Glipicanas/metabolismo , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Células Cultivadas , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , RNA Interferente Pequeno/metabolismo
6.
Liver Cancer ; 6(4): 287-296, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29234632

RESUMO

INTRODUCTION: Primary liver cancer is a significant cause of cancer-related death in both the United States and the world at large. Hepatocellular carcinoma comprises 90% of these primary liver cancers and has numerous known etiologies. Evaluation of these identified etiologies and other traditional risk factors cannot explain the high incidence rates of hepatocellular carcinoma in Texas. Texas is home to the second largest petrochemical industry and agricultural industry in the nation; industrial activity and exposure to pathogenic chemicals have never been assessed as potential links to the state's increased incidence rate of hepatocellular carcinoma. METHODS: The association between the county-level concentrations of 4 air pollutants known to be linked to liver cancer, vinyl chloride, arsenic, benzene, and 1,3-butadiene, and hepatocellular carcinoma rates was evaluated using nonparametric generalized additive logistic regression and gamma regression models. Hepatocellular carcinoma incidence rates for 2000-2013 were evaluated in comparison to 1996 and 1999 pollution concentrations and hepatocellular carcinoma rates for the subset of 2006-2013 were evaluated in comparison to 2002 and 2005 pollution concentrations, respectively. RESULTS: The analysis indicates that the relationship between the incidence of liver cancer and air pollution and risk factors is nonlinear. There is a consistent significant positive association between the incidence of liver cancer and hepatitis C prevalence rates (gamma all years, p < 0.05) and vinyl chloride concentrations (logistic 2002 and 2005, p < 0.0001; gamma 2002 and 2005, p < 0.05). CONCLUSIONS: This study suggests that vinyl chloride is a significant contributor to the incidence of liver cancer in Texas. The relationship is notably nonlinear. Further, the study supports the association between incidence of liver cancer and prevalence of hepatitis B.

7.
PLoS One ; 12(10): e0185610, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29016628

RESUMO

The incidence of hepatocellular carcinoma (HCC), the most common primary liver cancer, is increasing in the US and tripled during the past two decades. The reasons for such phenomenon remain poorly understood. Texas is among continental states with the highest incidence of liver cancer with an annual increment of 5.7%. Established risk factors for HCC include Hepatitis B and C (HBV, HCV) viral infection, alcohol, tobacco and suspected risk factors include obesity and diabetes. While distribution of these risk factors in the state of Texas is similar to the national data and homogeneous, the incidence of HCC in this state is exceptionally higher than the national average and appears to be dishomogeneous in various areas of the state suggesting that other non-recognized risk factors might play a role. No population-based studies are currently available investigating the effect of exposure to Hazardous Air Pollutants (HAPs) as a contributing risk factor for liver cancer. Incidence rate of liver cancer in Texas by counties for the time period between 2002 and 2012 was obtained from the Texas Cancer Registry (TCR). Through Principal Component Analysis (PCA) a subgroup of pollutants, explaining almost all the dataset variability, were identified and used to cluster Texas counties. The analysis generated 4 clusters showing liver cancer rate either higher or lower than national average in association with either high or low levels of HAPs emission in the environment. The study shows that the selected relevant HAPs, 10 among 253 analyzed, produce a significant correlation (P = 0.01-0.05) and some of these have been previously identified as carcinogens. An association between the increased production and consequent exposure to these HAPs and a higher presence of liver cancer in certain counties is suggested. This study provides a new insight on this complex multifactorial disease suggesting that environmental substances might play a role in the etiology of this cancer.


Assuntos
Poluentes Atmosféricos/efeitos adversos , Carcinoma Hepatocelular/epidemiologia , Exposição Ambiental/efeitos adversos , Neoplasias Hepáticas/epidemiologia , Compostos Orgânicos/efeitos adversos , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/etiologia , Carcinoma Hepatocelular/patologia , Monitoramento Ambiental , Humanos , Incidência , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/etiologia , Neoplasias Hepáticas/patologia , Análise de Componente Principal , Fatores de Risco , Texas/epidemiologia
8.
Oncol Rep ; 37(3): 1291-1300, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28098909

RESUMO

Glypican-3 (GPC-3), a transmembrane heparan sulfate proteoglycan (HSPG), has recently been investigated as a player in tissue-dependent cellular signaling, specifically as a regulator of growth. Noteworthy, the regulatory protein has been implicated in both stimulatory and inhibitory pathways involving cell growth. Initially, GPC-3 was thought to act as a cell cycle regulator, as a loss-of-function mutation in the gene caused a hyper-proliferative state known as Simpson-Golabi-Behmel (SGB) overgrowth syndrome. Additionally, certain cancer types have displayed a downregulation of GPC-3 expression. More recently, the protein has been evaluated as a useful marker for hepatocellular carcinoma (HCC) due to its increased expression in the liver during times of growth. In contrast, the GPC-3 marker is not detectable in normal adult liver. Immunotherapy that targets GPC-3 and its affiliated proteins is under investigation as these new biomarkers may hold potential for the detection and treatment of HCC and other diseases in which GPC-3 may be overexpressed. Studies have reported that an overexpression of GPC-3 in HCC predicts a poorer prognosis. This prognostic value further pushes the question regarding GPC-3's role in the regulation and progression of HCC. This review will summarize the current knowledge regarding the clinical aspects of GPC-3, while also synthesizing the current literature with the aim to better understand this molecule's biological interactions at a molecular level, not only in the liver, but in the rest of the body as well. Due to the existing gap in the literature surrounding GPC-3, we believe further investigation of function, structure and domains, cellular localization, and other subfields is warranted to evaluate the protein as a whole, as well as its part in the study of HCC.


Assuntos
Carcinoma Hepatocelular/patologia , Transformação Celular Neoplásica/patologia , Glipicanas/metabolismo , Hepatócitos/patologia , Neoplasias Hepáticas/patologia , Adulto , Carcinoma Hepatocelular/metabolismo , Transformação Celular Neoplásica/metabolismo , Hepatócitos/metabolismo , Humanos , Neoplasias Hepáticas/metabolismo
9.
Transplantation ; 100(10): 2146-52, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27490419

RESUMO

BACKGROUND: We have previously shown that patients listed for orthotopic liver transplantation (OLT) in United Network for Organ Sharing Region 4 (Texas and Oklahoma) have higher waitlist mortality rates when residing more than 30 miles from specialized liver transplant centers (LTC). Considering that findings might only be exclusive for this region with its peculiarities in terms of having the highest land surface extensions, lowest population densities, and largest rural populations. We investigated the entire OLT patient population in the United States to assess if our previous regional findings are nationally validated and if a rural, micropolitan, or metropolitan residence location affects outcome of waitlisted OLT patients in the nation. METHODS: Patients waiting for OLT in the United States from 2002 to 2012 were stratified by distance from the patients' residence to LTC and by Rural Urban Commuting Area (RUCA) codes classification. Statistical analyses were performed to evaluate risk of mortality on the waitlist and the likelihood to receive an OLT using a Cox proportional hazards model and a generalized additive model with a logistic link. RESULTS: Survival time and probability of death while on the waitlist for OLT using distance to LTC showed significant increased risk with the distance (P = 0.001 and P < 0.0001, respectively). At the same time, using RUCA classification as the variable did not show significance (P = 0.14 and P = 0.73, respectively). CONCLUSIONS: Distance from an LTC is a risk factor of mortality on the waitlist for OLT, whereas RUCA classification is not a significant factor.


Assuntos
Doença Hepática Terminal/mortalidade , Acessibilidade aos Serviços de Saúde , Transplante de Fígado/mortalidade , Viagem , Listas de Espera , Adulto , Idoso , Doença Hepática Terminal/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Risco , Estados Unidos/epidemiologia
10.
PLoS One ; 11(4): e0153613, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27074018

RESUMO

Isolation of hepatocytes from cirrhotic human livers and subsequent primary culture are important new tools for laboratory research and cell-based therapeutics in the study of hepatocellular carcinoma (HCC). Using such techniques, we have previously identified different subpopulations of human hepatocytes and among them one is showing a progressive transformation of hepatocytes in HCC-like cells. We have hypothesized that increasing the distance from the neoplastic lesion might affect hepatocyte function and transformation capacity. However, limited information is available in comparing the growth and proliferation of human hepatocytes obtained from different areas of the same cirrhotic liver in relation to their distance from the HCC lesion. In this study, hepatocytes from 10 patients with cirrhosis and HCC undergoing surgical resections from specimens obtained at a proximal (CP) and distal (CD) distance from the HCC lesion were isolated and placed in primary culture. CP hepatocytes (CP-Hep) were isolated between 1 to 3 cm (leaving at least 1cm margin to avoid cancer cells and/or satellite lesions), while CD hepatocytes (CD-Hep) were isolated from more than 5 cm or from the contralateral-lobe. A statistical model was built to analyze the proliferation rates of these cells and we evaluated expression of HCC markers (Glypican-3 (GPC3), αSmooth Muscle Actin (α-SMA) and PCNA). We observed a significant difference in proliferation and in-vitro growth showing that CP-Hep had a proliferation pattern and rate significantly different than CD-Hep. Based on these data, this model can provide information to predict growth of human hepatocytes in primary culture in relation to their pre-cancerous state with significant differences in the HCC markers expression. This model provides an important innovative tool for in-vitro analysis of HCC.


Assuntos
Carcinoma Hepatocelular/patologia , Proliferação de Células , Hepatócitos/patologia , Cirrose Hepática/patologia , Neoplasias Hepáticas/patologia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Células Tumorais Cultivadas
11.
World J Transplant ; 6(1): 1-9, 2016 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-27011901

RESUMO

Inadequate absorptive surface area poses a great challenge to the patients suffering a variety of intestinal diseases causing short bowel syndrome. To date, these patients are managed with total parenteral nutrition or intestinal transplantation. However, these carry significant morbidity and mortality. Currently, by emergence of tissue engineering, anticipations to utilize an alternative method to increase the intestinal absorptive surface area are increasing. In this paper, we will review the improvements made over time in attempting elongating the intestine with surgical techniques as well as using intestinal bioengineering. Performing sequential intestinal lengthening was the preliminary method applied in humans. However, these methods did not reach widespread use and has limited outcome. Subsequent experimental methods were developed utilizing scaffolds to regenerate intestinal tissue and organoids unit from the intestinal epithelium. Stem cells also have been studied and applied in all types of tissue engineering. Biomaterials were utilized as a structural support for naive cells to produce bio-engineered tissue that can achieve a near-normal anatomical structure. A promising novel approach is the elongation of the intestine with an acellular biologic scaffold to generate a neo-formed intestinal tissue that showed, for the first time, evidence of absorption in vivo. In the large intestine, studies are more focused on regeneration and engineering of sphincters and will be briefly reviewed. From the review of the existing literature, it can be concluded that significant progress has been achieved in these experimental methods but that these now need to be fully translated into a pre-clinical and clinical experimentation to become a future viable therapeutic option.

12.
Int J Oncol ; 48(3): 1205-17, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26717856

RESUMO

Hepatocellular carcinoma (HCC) is the most common primary liver cancer. Currently, there is limited knowledge of neoplastic transformation of hepatocytes in HCC. In clinical practice, the high rate of HCC local recurrence suggests the presence of different hepatocyte populations within the liver and particularly in the tumor proximity. The present study investigated primary human hepatocyte cultures obtained from liver specimens of patients affected by cirrhosis and HCC, their proliferation and transformation. Liver samples were obtained from seven HCC cirrhotic patients and from three patients with normal liver (NL). Immediately after surgery, cell outgrowth and primary cultures were obtained from the HCC lesion, the cirrhotic tissue proximal (CP, 1-3 cm) and distal (CD, >5 cm) to the margin of the neoplastic lesion, or from NL. Cells were kept in culture for 16 weeks. Morphologic analyses were performed and proliferation rate of the different cell populations compared over time. Glypican-3, Heppar1, Arginase1 and CD-44 positivity were tested. The degree of invasiveness of cells acquiring neoplastic characteristics was studied with a transwell migration assay. We observed that HCC cells maintained their morphology and unmodified neoplastic characteristics when cultured. Cells isolated from CP, showed a progressive morphologic transformation in HCC-like cells accompanied by modification of markers expression with signs of invasiveness. Absence of HCC contamination in the CP isolates was confirmed. In CD samples some of these characteristics were present and at significantly lower levels. With the present study, we are the first to have identified and describe the existence of human hepatocytes near the cancerous lesion that can transform in HCC in vitro.


Assuntos
Carcinoma Hepatocelular/metabolismo , Transformação Celular Neoplásica , Hepatócitos/citologia , Neoplasias Hepáticas/metabolismo , Idoso , Antígenos de Neoplasias/metabolismo , Arginase/metabolismo , Movimento Celular , Proliferação de Células , Feminino , Citometria de Fluxo , Glipicanas/metabolismo , Humanos , Receptores de Hialuronatos/metabolismo , Imuno-Histoquímica , Cirrose Hepática/fisiopatologia , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica
13.
J Gastrointest Surg ; 20(1): 34-42; discussion 42, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26464017

RESUMO

A promising therapeutic approach for intestinal failure consists in elongating the intestine with a bio-engineered segment of neo-formed autologous intestine. Using an acellular biologic scaffold (ABS), we, and others, have previously developed an autologous bio-artificial intestinal segment (BIS) that is morphologically similar to normal bowel in rodents. This neo-formed BIS is constructed with the intervention of naïve stem cells that repopulate the scaffold in vivo, and over a period of time, are transformed in different cell populations typical of normal intestinal mucosa. However, no studies are available to demonstrate that such BIS possesses functional absorptive characteristics necessary to render this strategy a possible therapeutic application. The aim of this study was to demonstrate that the BIS generated has functional absorptive capacity. Twenty male August × Copenhagen-Irish (ACI) rats were used for the study. Two-centimeter sections of ABS were transplanted in the anti-mesenteric border of the small bowel. Animals were studied at 4, 8, and 12 weeks post-engraftment. Segments of intestine with preserved vascular supply and containing the BIS were isolated and compared to intestinal segments of same length in sham control animals (n = 10). D-Xylose solution was introduced in the lumen of the intestinal segments and after 2 h, urine and blood were collected to evaluate D-Xylose levels. Quantitative analysis was performed using ELISA. Morphologic, ultrastructural, and indirect functional absorption analyses were also performed. We observed neo-formed intestinal tissue with near-normal mucosa post-implantation as expected from our previously developed model. Functional characteristics such as morphologically normal enterocytes (and other cell types) with presence of brush borders and preserved microvilli by electron microscopy, preserved water, and ion transporters/channels (by aquaporin and cystic fibrosis transmembrane conductance regulator (CFTR)) were also observed. The capacity of BIS containing neo-formed mucosa to increase absorption of d-Xylose in the blood compared to normal intestine was also confirmed. With this study, we demonstrated for the first time that BIS obtained from ABS has functional characteristics of absorption confirming its potential for therapeutic interventions.


Assuntos
Órgãos Bioartificiais , Absorção Intestinal , Intestino Delgado/fisiologia , Engenharia Tecidual/métodos , Alicerces Teciduais , Animais , Mucosa Intestinal/anatomia & histologia , Mucosa Intestinal/fisiologia , Mucosa Intestinal/cirurgia , Intestino Delgado/anatomia & histologia , Intestino Delgado/cirurgia , Masculino , Ratos
14.
J Alzheimers Dis ; 47(2): 329-33, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26401556

RESUMO

Experimental evidence suggests that the protein phosphatase calcineurin mediates the action of amyloid-ß (Aß) oligomers, the most toxic amyloid species thought to drive initial cognitive decline in Alzheimer's disease (AD). However, there is currently no evidence that inhibition of calcineurin could prevent the onset of AD in humans. Here, we report for the first time that individuals chronically treated with calcineurin inhibitors to prevent solid organ transplant rejection have a significantly lower incidence of AD/dementia as compared to the general population. This result prompts further clinical development of calcineurin inhibition as a viable treatment for AD.


Assuntos
Inibidores de Calcineurina/uso terapêutico , Demência/epidemiologia , Rejeição de Enxerto/tratamento farmacológico , Transplante de Órgãos/métodos , Idoso , Idoso de 80 Anos ou mais , Feminino , Rejeição de Enxerto/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
15.
Cell Transplant ; 24(1): 11-23, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-24143907

RESUMO

Better results have been recently reported in clinical pancreatic islet transplantation (ITX) due mostly to improved isolation techniques and immunosuppression; however, some limitations still exist. It is known that following transplantation, 30% to 60% of the islets are lost. In our study, we have investigated 1) the role of size as a factor affecting islet engraftment and 2) potential procedural manipulations to increase the number of smaller functional islets that can be transplanted. C57/BL10 mice were used as donors and recipients in a syngeneic islet transplant model. Isolated islets were divided by size (large, >300 µm; medium 150-300 µm; small, <150 µm). Each size was transplanted in chemically induced diabetic mice as full (600 IEQ), suboptimal (400 IEQ), and marginal mass (200 IEQ). Control animals received all size islets. Engraftment was defined as reversal of diabetes by day 7 posttransplantation. When the superiority of smaller islets was observed, strategies of overdigestion and fragmentation were adopted during islet isolation in the attempt to reduce islet size and improve engraftment. Smaller islets were significantly superior in engraftment compared to medium, large, and control (all sizes) groups. This was more evident when marginal mass data were compared. In all masses, success decreased as islet size increased. Once islets were engrafted, functionality was not affected by size. When larger islets were fragmented, a significant decrease in islet functionality was observed. On the contrary, if pancreata were slightly overdigested, although not as successful as small naive islets, an increase in engraftment was observed when compared to the control group. In conclusion, smaller islets are superior in engraftment following islet transplantation. Fragmentation has a deleterious effect on islet engraftment. Islet isolations can be performed by reducing islet size with slight overdigestion, and it can be safely adopted to improve clinical outcome.


Assuntos
Diabetes Mellitus Experimental , Sobrevivência de Enxerto , Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas/patologia , Animais , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Experimental/cirurgia , Masculino , Camundongos , Tamanho do Órgão , Transplante Isogênico
16.
Clin Chem Lab Med ; 52(6): 899-909, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24406287

RESUMO

BACKGROUND: Hyper-methylation of CpG dinucleotides in the promoter region of inhibitor of cyclin-dependent kinase 4A (INK4A) has been reported in 60%-80% of hepatocellular carcinoma (HCC). As INK4A promoter hypermethylation event occurs early in HCC progression, the quantification of INK4A promoter methylation in blood sample may represent a useful biomarker for non-invasive diagnosis and prediction of response to therapy. METHODS: We examined INK4A promoter methylation using circulating cell-free DNA (ccfDNA) in a total of 109 serum specimens, including 66 HCC and 43 benign chronic liver diseases. Methylation of the individual seven CpG sites was examined using pyrosequencing. RESULTS: Our results showed that there were significantly higher levels of methylated INK4A in HCC specimens than controls and that the seven CpG sites had different levels of methylation and might exist in different PCR amplicons. The area under receiver operating characteristic (ROC) curve was 0.82, with 65.3% sensitivity and 87.2% specificity at 5% (LOD), 39.0% sensitivity and 96.5% specificity at 7% LOD, and 20.3% sensitivity and 98.8% specificity at 10% LOD, respectively. CONCLUSIONS: Our results support additional studies incorporating INK4A methylation testing of ccfDNA to further validate the diagnostic, predictive, and prognostic characteristics of this biomarker in HCC patients. The knowledge of the existence of epi-alleles should help improve assay design to maximize detection.


Assuntos
Carcinoma Hepatocelular/genética , Inibidor p16 de Quinase Dependente de Ciclina/genética , Metilação de DNA , DNA/sangue , Neoplasias Hepáticas/genética , Regiões Promotoras Genéticas/genética , Análise de Sequência de DNA/métodos , Alelos , Sequência de Bases , Carcinoma Hepatocelular/sangue , Linhagem Celular Tumoral , Ilhas de CpG/genética , DNA/genética , Humanos , Neoplasias Hepáticas/sangue
17.
Mol Cell Proteomics ; 12(12): 3640-52, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24008390

RESUMO

Chronic hepatic disease damages the liver, and the resulting wound-healing process leads to liver fibrosis and the subsequent development of cirrhosis. The leading cause of hepatic fibrosis and cirrhosis is infection with hepatitis C virus (HCV), and of the patients with HCV-induced cirrhosis, 2% to 5% develop hepatocellular carcinoma (HCC), with a survival rate of 7%. HCC is one of the leading causes of cancer-related death worldwide, and the poor survival rate is largely due to late-stage diagnosis, which makes successful intervention difficult, if not impossible. The lack of sensitive and specific diagnostic tools and the urgent need for early-stage diagnosis prompted us to discover new candidate biomarkers for HCV and HCC. We used aptamer-based fractionation technology to reduce serum complexity, differentially labeled samples (six HCV and six HCC) with fluorescent dyes, and resolved proteins in pairwise two-dimensional difference gel electrophoresis. DeCyder software was used to identify differentially expressed proteins and spots picked, and MALDI-MS/MS was used to determine that ApoA1 was down-regulated by 22% (p < 0.004) in HCC relative to HCV. Differential expression quantified via two-dimensional difference gel electrophoresis was confirmed by means of (18)O/(16)O stable isotope differential labeling with LC-MS/MS zoom scans. Technically independent confirmation was demonstrated by triple quadrupole LC-MS/MS selected reaction monitoring (SRM) assays with three peptides specific to human ApoA1 (DLATVYVDVLK, WQEEMELYR, and VSFLSALEEYTK) using (18)O/(16)O-labeled samples and further verified with AQUA peptides as internal standards for quantification. In 50 patient samples (24 HCV and 26 HCC), all three SRM assays yielded highly similar differential expression of ApoA1 in HCC and HCV patients. These results validated the SRM assays, which were independently confirmed by Western blotting. Thus, ApoA1 is a candidate member of an SRM biomarker panel for early diagnosis, prognosis, and monitoring of HCC. Future multiplexing of SRM assays for other candidate biomarkers is envisioned to develop a biomarker panel for subsequent verification and validation studies.


Assuntos
Apolipoproteína A-I/genética , Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/genética , Regulação Neoplásica da Expressão Gênica , Hepatite C Crônica/genética , Cirrose Hepática/genética , Neoplasias Hepáticas/genética , Adulto , Sequência de Aminoácidos , Apolipoproteína A-I/sangue , Aptâmeros de Peptídeos/química , Biomarcadores Tumorais/sangue , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/etiologia , Diagnóstico Precoce , Eletroforese em Gel Bidimensional , Corantes Fluorescentes/química , Hepacivirus/isolamento & purificação , Hepatite C Crônica/sangue , Hepatite C Crônica/complicações , Hepatite C Crônica/diagnóstico , Humanos , Marcação por Isótopo , Cirrose Hepática/sangue , Cirrose Hepática/diagnóstico , Cirrose Hepática/etiologia , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/etiologia , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Isótopos de Oxigênio , Sensibilidade e Especificidade , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
18.
Lancet Oncol ; 14(1): 55-63, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23182627

RESUMO

BACKGROUND: Tivantinib (ARQ 197), a selective oral inhibitor of MET, has shown promising antitumour activity in hepatocellular carcinoma as monotherapy and in combination with sorafenib. We aimed to assess efficacy and safety of tivantinib for second-line treatment of advanced hepatocellular carcinoma. METHODS: In this completed, multicentre, randomised, placebo-controlled, double-blind, phase 2 study, we enrolled patients with advanced hepatocellular carcinoma and Child-Pugh A cirrhosis who had progressed on or were unable to tolerate first-line systemic therapy. We randomly allocated patients 2:1 to receive tivantinib (360 mg twice-daily) or placebo until disease progression. The tivantinib dose was amended to 240 mg twice-daily because of high incidence of treatment-emergent grade 3 or worse neutropenia. Randomisation was done centrally by an interactive voice-response system, stratified by Eastern Cooperative Oncology Group performance status and vascular invasion. The primary endpoint was time to progression, according to independent radiological review in the intention-to-treat population. We assessed tumour samples for MET expression with immunohistochemistry (high expression was regarded as ≥2+ in ≥50% of tumour cells). This study is registered with ClinicalTrials.gov, number NCT00988741. FINDINGS: 71 patients were randomly assigned to receive tivantinib (38 at 360 mg twice-daily and 33 at 240 mg twice-daily); 36 patients were randomly assigned to receive placebo. At the time of analysis, 46 (65%) patients in the tivantinib group and 26 (72%) of those in the placebo group had progressive disease. Time to progression was longer for patients treated with tivantinib (1·6 months [95% CI 1·4-2·8]) than placebo (1·4 months [1·4-1·5]; hazard ratio [HR] 0·64, 90% CI 0·43-0·94; p=0·04). For patients with MET-high tumours, median time to progression was longer with tivantinib than for those on placebo (2·7 months [95% CI 1·4-8·5] for 22 MET-high patients on tivantinib vs 1·4 months [1·4-1·6] for 15 MET-high patients on placebo; HR 0·43, 95% CI 0·19-0·97; p=0·03). The most common grade 3 or worse adverse events in the tivantinib group were neutropenia (ten patients [14%] vs none in the placebo group) and anaemia (eight [11%] vs none in the placebo group). Eight patients (21%) in the tivantinib 360 mg group had grade 3 or worse neutropenia compared with two (6%) patients in the 240 mg group. Four deaths related to tivantinib occurred from severe neutropenia. 24 (34%) patients in the tivantinib group and 14 (39%) patients in the placebo group had serious adverse events. INTERPRETATION: Tivantinib could provide an option for second-line treatment of patients with advanced hepatocellular carcinoma and well-compensated liver cirrhosis, particularly for patients with MET-high tumours. Confirmation in a phase 3 trial is needed, with a starting dose of tivantinib 240 mg twice-daily. FUNDING: ArQule, Daiichi Sankyo (Daiichi Sankyo Group).


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Neoplasias Hepáticas/tratamento farmacológico , Pirrolidinonas/administração & dosagem , Quinolinas/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/patologia , Intervalo Livre de Doença , Método Duplo-Cego , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/induzido quimicamente , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/classificação , Feminino , Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/efeitos adversos , Proteínas Proto-Oncogênicas c-met/metabolismo , Pirrolidinonas/efeitos adversos , Quinolinas/efeitos adversos
19.
Ann Hepatol ; 11(3): 326-9, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22481450

RESUMO

BACKGROUND AND AIMS: Despite effective vaccine available, hepatitis A remains a significant cause of morbidity and mortality worldwide including acute liver failure, transplantation and death. Vaccination rates for hepatitis A in the general population are low. Rates of hepatitis A vaccination in healthcare personnel (HCP) are unknown. We studied vaccination rate to hepatitis A in a cohort of HCP at a large US academic center. MATERIAL AND METHODS: An anonymous survey was circulated between 499 HCP at-risk of hepatitis A exposure at our Institution. Results were corrected for non-response rate and compared with the general US population using the 2007 CDC-National Immunization Survey. Rate of hepatitis A vaccination was compared with Institutional rate of vaccination for the Influenza 2009-2010 season. RESULTS: Rate of vaccination for hepatitis A in HCP was 28.8% (response rate 41.4%; 207/499), with 58.9% having completed the full series and 24.7% being tested for post-vaccination immunity. Acceptance rate among non-vaccinated subjects was 70.7%. HCP hepatitis A vaccination rate was statistically greater than the national general population (28.8 vs. 12.1%, p ≤ 0.031). A statistically significant greater vaccination rate was found among US born responders vs. foreign-born HCP (34.3 vs. 19.3%, p = 0.0324). Vaccination for hepatitis A was statistically inferior to that of Influenza (28.8 vs. 90%; P = 0.01). CONCLUSIONS: HCP have statistically higher vaccination rate for hepatitis A than the general population, but overall protection remains suboptimal with vaccination rate below those for mandatory vaccines. Further studies to determine whether hepatitis A vaccine is cost-effective in HCP are recommended.


Assuntos
Pessoal de Saúde , Vacinas contra Hepatite A/uso terapêutico , Vírus da Hepatite A/imunologia , Hepatite A/prevenção & controle , Estudos de Coortes , Estudos Transversais , Inquéritos Epidemiológicos , Hepatite A/epidemiologia , Hepatite A/imunologia , Humanos , Incidência , Estudos Retrospectivos , Fatores de Risco , Inquéritos e Questionários , Estados Unidos/epidemiologia
20.
Histol Histopathol ; 25(3): 277-86, 2010 03.
Artigo em Inglês | MEDLINE | ID: mdl-20054799

RESUMO

INTRODUCTION: The prevailing notion is that ischemia reperfusion injury of the small bowel induces transient changes that resolve within a few days post-occurrence. However, chronic injury has been described following a single ischemia reperfusion in the kidney. We proceeded to ascertain if a similar outcome is also witnessed in the small bowel. MATERIALS AND METHODS: ACI rats (n=32) underwent 1, 2 or 3 episodes of ischemia reperfusion by clamping the superior mesenteric artery for 45 minutes at 7-day intervals. Control groups included sham-operated (n=6) or non-operated (n=5) rats. Morphology was examined at day ninety post-ischemia reperfusion and immunostaining was used to evaluate macrophage infiltration, microvascular distribution, and apoptosis. RT-PCR was used to evaluate expression of Inter-Cellular Adhesion Molecule-1 (ICAM-1), transforming growth factor-beta (TGF-beta), Insulin Growth Factor-I (IGF-1), and Insulin Growth Factor-I Receptor (IGF-R). Intestinal function was evaluated by D-xylose performed 24 hours and 4, 8, and 12 weeks after reperfusion. RESULTS: Chronic morphologic changes were observed with degeneration of crypts, endothelial damage, matrix degeneration, and heightened lymphocyte degeneration within the Payer's patches. Major structural changes were characterized by villous atrophy from partial to total. The grade of histological injuries was significantly increased (P<0.001) after multiple ischemia reperfusion episodes. A higher number of apoptotic cells (P<0.001) and a prominent macrophage infiltration (P<0.05) was also witnessed. Altered expression of ICAM-1, TGF-beta, and IGF-1 was observed. At 24 hours after ischemia reperfusion D-xylose absorption was diminished, returning to baseline values within 4 weeks and becoming abnormal again at 8 and 12 weeks (P<0.05). CONCLUSIONS: Unlike the prevailing conviction, these data demonstrate that transient ischemia reperfusion repeated injuries of the small bowel result in chronic intestinal damage.


Assuntos
Mucosa Intestinal/patologia , Intestino Delgado/patologia , Intestino Delgado/fisiopatologia , Traumatismo por Reperfusão/patologia , Traumatismo por Reperfusão/fisiopatologia , Animais , Apoptose/fisiologia , Atrofia/patologia , Imuno-Histoquímica , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like I/metabolismo , Molécula 1 de Adesão Intercelular/genética , Molécula 1 de Adesão Intercelular/metabolismo , Absorção Intestinal/fisiologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/fisiopatologia , Intestino Delgado/metabolismo , Masculino , Ratos , Ratos Endogâmicos ACI , Receptor IGF Tipo 1/genética , Receptor IGF Tipo 1/metabolismo , Traumatismo por Reperfusão/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Tempo , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo
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