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1.
Transpl Infect Dis ; 20(1)2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29111569

RESUMO

BACKGROUND: Direct-acting antivirals (DAAs) have substantially increased sustained virological response rates after liver transplantation, with improved tolerance compared to interferon-based therapy. The influence of immunosuppressive agents on the efficacy of DAAs has not been clarified. METHODS: Subgenomic hepatitis C virus (HCV) replicons for genotype (GT) 1b, 2b, 3a, and 4a were treated with the mammalian target of rapamycin (mTOR) inhibitors everolimus and sirolimus or with the calcineurin inhibitors (CNIs) cyclosporine or tacrolimus, either alone or in combination with selected DAAs. Cell proliferation-related effects were excluded with MTT assays. HCV replication activity was quantified by quantitative real-time polymerase chain reaction or luciferase assay. RESULTS: Addition of either mTOR inhibitor to the DAA daclatasvir (DAC) resulted in a 30% increase in antiviral activity compared to DAC alone for HCV GT2a, GT3a, and GT4a (all P ≤ .01). Similar results were obtained using sofosbuvir and ledipasvir. In contrast, addition of either mTOR inhibitor to DAC induced a 30% reduction in antiviral activity in GT1b cells (P ≤ .01 vs DAC alone). Neither CNI affects the antiviral activity of the DAAs in any HCV GT. CONCLUSION: For patients with HCV GT2a, GT3a, or GT4a infection, mTOR-based immunosuppressive therapy may be beneficial. CNI-based therapy may be more efficacious in GT1b patients, as mTOR inhibitors seem to impair antiviral efficacy of DAAs in HCV GT1b infection.


Assuntos
Antivirais/farmacologia , Genótipo , Hepacivirus/efeitos dos fármacos , Hepacivirus/genética , Imunossupressores/farmacologia , Benzimidazóis/farmacologia , Inibidores de Calcineurina/farmacologia , Carbamatos , Linhagem Celular , Ciclosporina/farmacologia , Everolimo/farmacologia , Fluorenos/farmacologia , Hepatite C/tratamento farmacológico , Hepatite C Crônica/tratamento farmacológico , Humanos , Imidazóis/farmacologia , Transplante de Fígado/efeitos adversos , Pirrolidinas , Sirolimo/farmacologia , Sofosbuvir/farmacologia , Valina/análogos & derivados , Replicação Viral/efeitos dos fármacos
2.
Ann Transplant ; 22: 446-454, 2017 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-28729525

RESUMO

BACKGROUND Liver transplantation (LT) remains the only curative treatment option for patients with defined stages of hepatocellular carcinoma (HCC). Up to 25% of patients show a tumor recurrence following transplantation. The correlation of fibrogenic markers prior to LT with HCC recurrence has not been characterized. We explored the expression of fibrogenic markers in tumor tissue and tumor-surrounding liver tissue of patients undergoing LT and correlated these findings with tumor recurrence. MATERIAL AND METHODS Fibrogenic marker expression in explanted livers was assessed using tumor and tumor-surrounding liver tissue from patients who recently underwent liver transplantation at our center with a follow-up period of at least 3 years. Tissue was analyzed for the expression of fibrogenic proteins and genes, as well as collagen deposition into the extracellular matrix. Results were correlated with HCC recurrence. RESULTS Patients with recurrent HCC following LT exhibited increased levels of fibrogenic markers on both protein and RNA level within the non-tumorous liver tissue in comparison to the tumor tissue itself. Patients who did not develop tumor recurrence up to 4 years after LT showed a reversed expression pattern of fibrogenic markers with decreased levels of ß-PDGFR, Collagen 1, and α-SMA in their non-tumorous liver tissue versus the tumor tissue at time of LT as assessed in protein and mRNA expression analysis. These findings correlated with analysis of collagen deposition in the liver. CONCLUSIONS Fibrogenic markers exhibit a differential expression pattern in HCC versus non-tumorous tissue in explanted livers of patients undergoing LT, showing a correlation with HCC recurrence.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/cirurgia , Transplante de Fígado , Fígado/patologia , Recidiva Local de Neoplasia/diagnóstico , Actinas/metabolismo , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Colágeno Tipo I/metabolismo , Feminino , Humanos , Fígado/metabolismo , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/metabolismo , Recidiva Local de Neoplasia/patologia , Proteínas Proto-Oncogênicas c-sis/metabolismo , Estudos Retrospectivos
3.
Cancer Med ; 5(10): 2942-2952, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27580702

RESUMO

The cytokine tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) induces apoptosis in liver cancer cells but not in normal liver cells. Therefore, TRAIL got credited to play a role in hepatocellular carcinoma (HCC) development and progression. Impaired expression of TRAIL in HCC cells and sequence variations in the TRAIL promoter may facilitate development, growth, and spread . The TRAIL promoter was sequenced from liver tissue of 93 patients undergoing partial liver resection (PRT) or liver transplantation (LT) for HCC. TRAIL mRNA expression was investigated by quantitative real-time PCR. A variant -1573T>C (single-nucleotide polymorphism; C, cytosine) SNP was characterized by electron mobility shift assay and supershift assays. Functionality of the -1573T>C SNP was analyzed in reporter gene assays and cell migration assays. In approximately 30% of HCC samples, a loss-of-function shift of the binding pattern due to a -1573T>C SNP was found within the human TRAIL promoter. Correlation analysis revealed significantly lower TRAIL expression in HCC samples with the -1573C sequence (P ≤ 0.05). Reporter gene assays revealed significantly reduced inducibility of the TRAIL promoter due to the -1573C sequence. The variant -1573C sequence impaired not only binding of transcription factors but also expression of TRAIL. Interestingly, this impairment resulted in enhanced migration activity and colony formation of the liver tumor cells. Our findings suggest that loss of function of the human TRAIL promoter due to the -1573T>C SNP leads to reduced expression and impaired inducibility of TRAIL, with the consequence of enhanced growth and migration of tumor cells, ultimately resulting in the progression of the HCC.


Assuntos
Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Polimorfismo de Nucleotídeo Único , Ligante Indutor de Apoptose Relacionado a TNF/genética , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Progressão da Doença , Células Hep G2 , Humanos , Neoplasias Hepáticas/metabolismo , Regiões Promotoras Genéticas , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo
4.
World J Hepatol ; 7(9): 1287-96, 2015 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-26019745

RESUMO

AIM: To characterize management of telaprevir (TVR)-based triple therapy of hepatitis C virus (HCV) reinfection after liver transplantation (LT). METHODS: We retrospectively analyzed safety and efficacy of telaprevir - based triple therapy in a single center cohort of 19 patients with HCV genotype (GT) 1 recurrence after LT, with respect to factors possibly predicting sustained viral response (SVR) or non-SVR. All patients were treated with TVR, pegylated (PEG) and ribavirine (RBV) for 12 wk followed by a dual phase with PEG/RBV for 12 wk in 7 patients and for 36 wk in 5 patients. RESULTS: In total 11/19 (58%) of patients achieved a sustained response. All (11/11) SVR patients showed a rapid viral response at treatment weeks 4 and 11/14 rapid virological response (RVR) patients achieved SVR. Notably, all (7/7) patients who completed 48 wk of therapy and 80% (4/5) patients who completed 24 wk of therapy achieved SVR24. Treatment failure was significantly (P > 0.049) more frequent in GT1a infection (5/7) compared to GT1b (3/12) infection and was associated with emergence of resistance-associated mutations in the NS3 protease domain. Bilirubin level at baseline is also related to SVR (P > 0.030). None of the patients had to discontinue treatment due to side effects. CONCLUSION: RVR, GT and bilirubin are clearly related to achievement of SVR. Providing a thorough patient selection and monitoring, a full course of TVR-based triple therapy in LT patients is feasible and achieves high SVR rates.

5.
Digestion ; 91(2): 117-27, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25662469

RESUMO

BACKGROUND: Although long-term survival rates for patients undergoing liver transplant (LT) for hepatocellular carcinoma (HCC) are good, the relatively high rate of tumor recurrence after LT necessitates the identification of biological parameters that supplement morphological predictors of recurrence. METHOD: From chart review we identified 175 patients who received liver transplantation due to HCC at our center between January 2000 and December 2013. We documented demographic and clinical data, as well as clinicopathological characteristics of the tumors, with a focus on liver values at the time of LT. RESULTS: HCC recurred in 23% of LT patients. Most recurrences (59%) occurred within 12 months after LT; hardly any recurrence was detected later than 3 years after LT. Recurrence was positively correlated with tumor size, tumor stage and alpha-fetoprotein level (AFP), and it was most likely with certain causes of liver disease. Interestingly, tumor recurrence was independently predicted by serum levels of glutamate dehydrogenase (GLDH) and alkaline phosphatase (AP) at the time of LT. CONCLUSIONS: Because all HCC recurrence occurs within 36 months after LT, HCC detected more than 3 years after LT may be considered de novo. Liver values, with GLDH and AP being the most preponderant, serve as easy-to-assess biomarkers which contribute to predict the risk of tumor recurrence.


Assuntos
Fosfatase Alcalina/sangue , Biomarcadores Tumorais/sangue , Carcinoma Hepatocelular/enzimologia , Glutamato Desidrogenase/sangue , Neoplasias Hepáticas/enzimologia , Transplante de Fígado , Recidiva Local de Neoplasia/enzimologia , Adulto , Idoso , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/cirurgia , Feminino , Fibrose/etiologia , Fibrose/cirurgia , Humanos , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Período Pós-Operatório , Estudos Retrospectivos , Risco , alfa-Fetoproteínas/análise
6.
Int J Cancer ; 136(4): E154-60, 2015 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-25123818

RESUMO

The proapoptotic molecule TNF-related apoptosis-inducing ligand (TRAIL) has earned attention because of its ability to induce apoptosis in liver cancer cells without damaging normal liver cells. It may play an important role in preventing the development and outgrowth of hepatocellular carcinoma (HCC). TRAIL expression was investigated in a large series of human HCCs. We analyzed liver tissue from 108 patients undergoing partial liver resection (PLR) or liver transplantation (LT) because of either HCC or other indications. TRAIL expression was correlated with the cause of liver disease, demographic and clinical variables and pathologic properties. Our analysis found that in 66% of HCCs TRAIL expression was significantly lower than in the surrounding non-cancerous liver tissue (p≤0.012). Separation by cause of disease showed that HCC TRAIL mRNA expression was lower in almost all groups than in non-cancerous tissue but most significantly lower in NASH-associated liver tumors. Interestingly, low HCC TRAIL expression was found to correlate with tumor size (p≤0.007) and stage, as well as with tumor recurrence after resection and poor survival rates. The results of this study suggest that low TRAIL mRNA levels may be both a dominant feature in HCC development and growth and a predictor of tumor recurrence and poorer survival rates.


Assuntos
Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Recidiva Local de Neoplasia/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Fígado/metabolismo , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Ligante Indutor de Apoptose Relacionado a TNF/genética , Carga Tumoral , Adulto Jovem
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