Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 222
Filtrar
1.
Artigo em Alemão | MEDLINE | ID: mdl-32211938

RESUMO

For more than 3500 years, metabolic disorders were recognized by symptoms similar to those indicating diabetes mellitus today. Over centuries, explanations remained elusive and shed sparse light on the origin of the disease and any treatments. The poor prognosis triggered myths and misconceptions, some even lasting until today. Two hundred years ago, major advances were made in the understanding of the pathophysiology, which has led to more successful treatments. Presently, useful preventive, diagnostic, and therapeutic procedures exist. However, old myths and misconceptions still influence the treatments. This article reviews ongoing myths dealing with the genesis and treatment of diabetes and the growing evidence for improved therapies.Increasingly more studies focus on cardiovascular endpoints while considering more realistic therapeutic goals. This paves the way to polyvalent treatment concepts reaching beyond the classic glucocentric treatment concept of type 2 diabetes. The introduction of molecular medicine, the current opportunities and future prospects of new drugs, personalized medicine, and technical innovations prompt hopes and expectations for a change of paradigms in therapeutic concepts. It is quite possible that traditional and newly generated myths will accompany this development. This has to be kept in mind when developing new concepts for treatment.


Assuntos
Glicemia/efeitos dos fármacos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/administração & dosagem , Insulina/administração & dosagem , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/sangue , Alemanha , Humanos , Prognóstico
3.
J Hepatol ; 69(1): 36-42, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29551705

RESUMO

BACKGROUND & AIMS: Routine HEV testing of blood products has recently been implemented in Great Britain and the Netherlands. The relevance of transfusion-transmitted HEV infections is still controversially discussed in Europe. METHODS: All blood donations at the University Medical Center Hamburg-Eppendorf were prospectively tested for HEV RNA by pooled PCR from October 2016 to May 2017. Reactive samples were individually retested. Additionally, stored samples from previous donations of positive donors were tested to determine the duration of HEV viraemia. HEV RNA-positive donors and a control cohort were asked to answer a questionnaire. RESULTS: Twenty-three out of 18,737 HEV RNA-positive donors were identified (0.12%). Only two of the positive donors (8.7%) presented with elevated aminotransferases at time of donation (alanine aminotransferase: 192 and 101 U/L). The retrospective analysis of all positive donors revealed that four asymptomatic donors had been HEV viraemic for up to three months with the longest duration of HEV viraemia exceeding four months. Despite the HEV-testing efforts, 14 HEV RNA-positive blood products were transfused into 12 immunocompromised and two immunocompetent patients. One recipient of these products developed fatal acute-on-chronic liver failure complicated by Pseudomonas septicemia. The questionnaire revealed that HEV RNA-positive donors significantly more often consumed raw pork meat (12 out of 18; 67%) than controls (89 out of 256; 35%; p = 0.01). In two donors, undercooked pork liver dishes were identified as the source of infection. HEV genotyping was possible in 7 out of 23 of HEV viraemic donors and six out of seven isolates belonged to HEV Genotype 3, Group 2. CONCLUSIONS: Prolonged HEV viraemia can be detected at a relatively high rate in Northern German blood donors, leading to transfusion-transmitted HEV infections in several patients with the risk of severe and fatal complications. Eating raw pork tartare represented a relevant risk for the acquisition of HEV infection. LAY SUMMARY: The relevance of transfusion-transmitted hepatitis E virus infections has been discussed controversially. Herein, we present the first report on routine hepatitis E virus screening of blood donations at a tertiary care centre in Germany. Hepatitis E viraemia was found at a relatively high rate of 0.12% among blood donors, which represents a relevant transfusion-related risk for vulnerable patient populations.


Assuntos
Doadores de Sangue , Vírus da Hepatite E/genética , Hepatite E/virologia , Hospedeiro Imunocomprometido , Programas de Rastreamento/métodos , RNA Viral/análise , Reação Transfusional/virologia , Adulto , Feminino , Alemanha/epidemiologia , Hepatite E/epidemiologia , Hepatite E/transmissão , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Estudos Retrospectivos , Reação Transfusional/epidemiologia , Adulto Jovem
4.
Eur J Gastroenterol Hepatol ; 30(1): 44-53, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29076939

RESUMO

BACKGROUND: Allocation of patients with hepatocellular carcinoma (HCC) to the adequate therapy is determined by both tumor burden and liver function. The Barcelona Clinic Liver Cancer (BCLC) staging system and therapeutic algorithm recommends transarterial chemoembolization (TACE) based on the best evidence available to patients with intermediate-stage HCC (BCLC-B). However, many centers also treat subgroups of patients outside these recommendations and with more advanced disease by TACE. The purpose of this study was to identify prognostic factors in a TACE cohort, including BCLC-B patients, as well as patients treated outside of BCLC-B, to test the prognostic capabilities of published staging systems and to optimize prognostication for TACE patients. PATIENTS AND METHODS: A cohort of 186 first-line TACE patients was analyzed. Independent prognostic factors were identified and used to construct the Munich-TACE score (M-TACE). M-TACE was tested against established staging systems (including BCLC and two recently published TACE-specific scores) and a ranking using concordance index and Akaike Information Criterion was performed. Finally, an external validation in an independent TACE cohort (n=71) was conducted. RESULTS: Bilirubin, Quick/international normalized ratio, C-reactive protein, creatinine, α-feto protein, and tumor extension were identified as independent prognostic factors and used to construct M-TACE. M-TACE identifies three distinct subgroups (P<0.0001) with median survival times of 35.2, 16.9, and 8.6 months, respectively. Compared with established staging systems, M-TACE showed the best prognostic capabilities in both cohorts of patients (cohort 1: c-index, 0.71; Akaike Information Criterion: 1276; cohort 2: c-index, 0.754). CONCLUSION: We identified independent risk factors for patients treated with TACE. The newly constructed M-TACE score is superior to established staging systems and might prove helpful to identify patients who are most suitable for TACE.


Assuntos
Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica , Técnicas de Apoio para a Decisão , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/terapia , Estadiamento de Neoplasias/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Biomarcadores Tumorais/sangue , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/mortalidade , Quimioembolização Terapêutica/efeitos adversos , Quimioembolização Terapêutica/mortalidade , Tomada de Decisão Clínica , Feminino , Humanos , Coeficiente Internacional Normatizado , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Seleção de Pacientes , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Reprodutibilidade dos Testes , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
5.
Int J Colorectal Dis ; 32(9): 1243-1251, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28681073

RESUMO

PURPOSE: γ-Catenin is a protein closely related to ß-catenin. While the overexpression of ß-catenin has been linked with impaired prognosis and survival in various malignancies, both oncogenic and tumor suppressor functions have been described for γ-catenin. Thus, its role in cancer remains controversial. In this study, we examined the impact of γ-catenin expression on the malignant potential of colorectal cancer cells. METHODS: γ-Catenin was knocked down by short interfering RNA in the γ-catenin-proficient DLD-1 cell line and stably overexpressed in the γ-catenin-deficient cell line RKO. The effects of these molecular manipulations on the malignant potential of the cell lines were tested in vitro and in vivo in a xenograft tumor model. RESULTS: γ-Catenin contributed to Wnt signaling independent of the cellular context. Unlike its sister molecule ß-catenin, γ-catenin inhibited cellular invasion and anoikis in cells endogenously expressing γ-catenin. In line with this tumor suppressor function, its de novo expression in RKO cells inhibited proliferation via cell cycle arrest. In a xenograft tumor model, overexpression of γ-catenin starkly reduced tumor growth in vivo. CONCLUSIONS: This is the first report demonstrating a tumor-suppressive effect of γ-catenin in colorectal cancer both in vitro and in vivo. Detailed in vitro analysis revealed that effects of γ-catenin differ in γ-catenin proficient and deficient cells, indicating that its function in colorectal cancer is dependent on the cellular context. This finding adds to our understanding of γ-catenin and may have implications for future studies of catenin/Wnt targeted cancer therapies.


Assuntos
Neoplasias Colorretais/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Animais , Anoikis , Pontos de Checagem do Ciclo Celular , Movimento Celular , Proliferação de Células , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Células HCT116 , Células HT29 , Humanos , Camundongos Nus , Interferência de RNA , Fatores de Tempo , Transfecção , Carga Tumoral , Proteínas Supressoras de Tumor/genética , Via de Sinalização Wnt , beta Catenina/genética , beta Catenina/metabolismo , gama Catenina/genética , gama Catenina/metabolismo
7.
Clin Gastroenterol Hepatol ; 14(11): 1612-1618.e3, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27085763

RESUMO

BACKGROUND & AIMS: Screening for colorectal cancer (CRC) using fecal occult blood tests (FOBT) is associated with reduced CRC incidence and mortality. Population-based FOBT screening has led to identification of CRCs at earlier stages and longer patient survival times. We investigated the stage distribution of CRCs detected by colonoscopy in a large outpatient cohort. METHODS: We performed a retrospective analysis of colonoscopies performed on 524,954 outpatients (age, ≥55 y) in Germany from January 2006 through December 2009. Patients with chronic inflammatory bowel diseases, and those with a personal history of adenoma or CRC, were excluded. Colonoscopy findings were categorized on the basis of the most advanced lesion found; histologic samples were obtained from all patients with suspected cancer and analyzed. Cancers were staged based on Union Internationale Contre le Cancer criteria. We analyzed absolute and relative frequencies of CRCs identified and tumor stages for patients who underwent colonoscopy for screening, evaluation of a positive FOBT, and evaluation of symptoms. RESULTS: Of the 6065 CRCs identified, 1750 were found in the screening group, 1075 in subjects with positive FOBT, and 3240 in patients with symptoms. Stage I CRC was detected more frequently in subjects who received screening colonoscopies (41.15%) or in those with positive FOBT (39.10%), than in individuals with symptoms (24.42%; P < .001). In contrast, the detection rates of stage IV CRC were 10.67%, 10.76%, and 18.64%, respectively (P < .001). We observed a shift toward lower T stages in the screening and FOBT work-up groups compared with the group with symptoms. Compared with subjects with symptoms, the odds of diagnosing CRC at an advanced stage were significantly lower in the screening group (odds ratio, 0.533; 95% confidence interval, 0.451-0.631) and the FOBT work-up group (odds ratio, 0.570; 95% confidence interval, 0.469-0.694). CONCLUSIONS: In this large population-based study, CRC detected by colonoscopies performed for screening and evaluation of positive FOBTs had a lower stage than those diagnosed by colonoscopies in symptomatic patients. These findings support the value of screening colonoscopy to reduce the burden of CRC.


Assuntos
Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/patologia , Detecção Precoce de Câncer/estatística & dados numéricos , Estadiamento de Neoplasias , Índice de Gravidade de Doença , Idoso , Idoso de 80 Anos ou mais , Colonoscopia , Neoplasias Colorretais/epidemiologia , Feminino , Alemanha/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
8.
Oncotarget ; 7(8): 9477-90, 2016 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-26843614

RESUMO

PURPOSE: DNA repair defects due to detrimental BRCA2-mutations confer increased susceptibility towards DNA interstrand-crosslinking (ICL) agents and define patient subpopulations for individualized genotype-based cancer therapy. However, due to the side effects of these drugs, there is a need to identify additional agents, which could be used alone or in combination with ICL-agents. Therefore, we investigated whether BRCA2-mutations might also increase the sensitivity towards TRAIL-receptors (TRAIL-R)-targeting compounds. EXPERIMENTAL DESIGN: Two independent model systems were applied: a BRCA2 gene knockout and a BRCA2 gene complementation model. The effects of TRAIL-R-targeting compounds and ICL-agents on cell viability, apoptosis and cell cycle distribution were compared in BRCA2-proficient versus-deficient cancer cells in vitro. In addition, the effects of the TRAIL-R2-targeting antibody LBY135 were assessed in vivo using a murine tumor xenograft model. RESULTS: BRCA2-deficient cancer cells displayed an increased sensitivity towards TRAIL-R-targeting agents. These effects exceeded and were mechanistically distinguishable from the well-established effects of ICL-agents. In vitro, ICL-agents expectedly induced an early cell cycle arrest followed by delayed apoptosis, whereas TRAIL-R-targeting compounds caused early apoptosis without prior cell cycle arrest. In vivo, treatment with LBY135 significantly reduced the tumor growth of BRCA2-deficient cancer cells in a xenograft model. CONCLUSIONS: BRCA2 mutations strongly increase the in vitro- and in vivo-sensitivity of cancer cells towards TRAIL-R-mediated apoptosis. This effect is mechanistically distinguishable from the well-established ICL-hypersensitivity of BRCA2-deficient cells. Our study thus defines a new genetic subpopulation of cancers susceptible towards TRAIL-R-targeting compounds, which could facilitate novel therapeutic approaches for patients with BRCA2-deficient tumors.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Proteína BRCA2/genética , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Reagentes de Ligações Cruzadas/farmacologia , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/antagonistas & inibidores , Animais , Anticorpos Monoclonais Murinos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular/efeitos dos fármacos , Reparo do DNA/genética , Humanos , Camundongos , Interferência de RNA , RNA Interferente Pequeno/genética
9.
Oncotarget ; 7(6): 7080-95, 2016 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-26755646

RESUMO

The phosphoinositide 3-kinase-related kinase ATR represents a central checkpoint regulator and mediator of DNA-repair. Its inhibition selectively eliminates certain subsets of cancer cells in various tumor types, but the underlying genetic determinants remain enigmatic. Here, we applied a synthetic lethal screen directed against 288 DNA-repair genes using the well-defined ATR knock-in model of DLD1 colorectal cancer cells to identify potential DNA-repair defects mediating these effects. We identified a set of DNA-repair proteins, whose knockdown selectively killed ATR-deficient cancer cells. From this set, we further investigated the profound synthetic lethal interaction between ATR and POLD1. ATR-dependent POLD1 knockdown-induced cell killing was reproducible pharmacologically in POLD1-depleted DLD1 cells and a panel of other colorectal cancer cell lines by using chemical inhibitors of ATR or its major effector kinase CHK1. Mechanistically, POLD1 depletion in ATR-deficient cells caused caspase-dependent apoptosis without preceding cell cycle arrest and increased DNA-damage along with impaired DNA-repair. Our data could have clinical implications regarding tumor genotype-based cancer therapy, as inactivating POLD1 mutations have recently been identified in small subsets of colorectal and endometrial cancers. POLD1 deficiency might thus represent a predictive marker for treatment response towards ATR- or CHK1-inhibitors that are currently tested in clinical trials.


Assuntos
Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , DNA Polimerase III/deficiência , Enzimas Reparadoras do DNA/antagonistas & inibidores , RNA Interferente Pequeno/genética , Proteínas Mutadas de Ataxia Telangiectasia/antagonistas & inibidores , Proteínas Mutadas de Ataxia Telangiectasia/genética , Western Blotting , Ciclo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/tratamento farmacológico , Dano ao DNA/efeitos dos fármacos , DNA Polimerase III/genética , Reparo do DNA/efeitos dos fármacos , Enzimas Reparadoras do DNA/genética , Inibidores Enzimáticos/farmacologia , Fluorometria , Ensaios de Triagem em Larga Escala , Histonas/metabolismo , Humanos , Mutação/genética , Proteínas Quinases/química , Proteínas Quinases/metabolismo , Transdução de Sinais/efeitos dos fármacos , Células Tumorais Cultivadas
10.
Neuroendocrinology ; 103(3-4): 383-401, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26338447

RESUMO

BACKGROUND/AIMS: The hepatocyte growth factor/transmembrane tyrosine kinase receptor c-Met has been defined as a potential target in antitumoral treatment of various carcinomas. We aimed to investigate the direct effect of c-Met inhibition on neuroendocrine tumor cells in vitro. METHODS: The effects of the multi-tyrosine kinase inhibitors cabozantinib and tivantinib and of the highly specific c-Met inhibitor INC280 were investigated in human pancreatic neuroendocrine BON1, bronchopulmonary NCI-H727 and midgut GOT1 cells in vitro. RESULTS: INC280, cabozantinib and tivantinib inhibited c-Met phosphorylation, respectively. However, while equimolar concentrations (10 µM) of cabozantinib and tivantinib inhibited cell viability and cell migration, INC280 had no inhibitory effect. Knockdown experiments with c-Met siRNA also did not demonstrate effects on cell viability. Cabozantinib and tivantinib caused a G2 arrest in neuroendocrine tumor cells. CONCLUSIONS: Our in vitro data suggest that c-Met inhibition alone is not sufficient to exert direct antitumoral or antimigratory effects in neuroendocrine tumor cells. The multi-tyrosine kinase inhibitors cabozantinib and tivantinib show promising antitumoral and antimigratory effects in neuroendocrine tumor cells, which are most probably 'off-target' effects, not mediated by c-Met.


Assuntos
Anilidas/farmacologia , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Piridinas/farmacologia , Pirrolidinonas/farmacologia , Quinolinas/farmacologia , Benzamidas , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Receptores ErbB/metabolismo , Citometria de Fluxo , Humanos , Imidazóis/farmacologia , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Tumores Neuroendócrinos/patologia , Proteína Oncogênica v-akt/metabolismo , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo , Transfecção , Triazinas/farmacologia
11.
PLoS One ; 10(12): e0143830, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26636335

RESUMO

BACKGROUND: The mTORC1-inhibitor everolimus shows limited efficacy in treating patients with gastro-entero-pancreatic or pulmonary neuroendocrine tumors (NETs), and poor outcome in patients with malignant pheochromocytoma or hepatic carcinoma. We speculated that any effect may be enhanced by antogonising other signaling pathways. METHODS: Therefore, we tested the effect of lovastatin--known to inhibit both ERK and AKT signaling--and everolimus, separately and in combination, on cell viability and signaling pathways in human midgut (GOT), pancreatic (BON1), and pulmonary (H727) NET, hepatocellular carcinoma (HepG2, Huh7), and mouse pheochromocytoma (MPC, MTT) cell lines. RESULTS: Lovastatin and everolimus separately significantly reduced cell viability in H727, HepG2, Huh7, MPC and MTT cells at clinically relevant doses (P ≤ 0.05). However, high doses of lovastatin were necessary to affect GOT or BON1 cell viability. Clinically relevant doses of both drugs showed additive anti-tumor effects in H727, HepG2, Huh7, MPC and MTT cells (P ≤ 0.05), but not in BON1 or GOT cells. In all cell lines investigated, lovastatin inhibited EGFR and AKT signaling. Subsequently, combination treatment more strongly inhibited EGFR and AKT signaling than everolimus alone, or at least attenuated everolimus-induced EGFR or AKT activation. Vice versa, everolimus constantly decreased pp70S6K and combination treatment more strongly decreased pp70S6K than lovastatin alone, or attenuated lovastatin-induced p70S6K activation: in BON1 cells lovastatin-induced EGFR inhibition was least pronounced, possibly explaining the low efficacy and consequent absent additive effect. CONCLUSION: In summary, clinically relevant doses of lovastatin and everolimus were effective separately and showed additive effects in 5 out of 7 cell lines. Our findings emphasize the importance of targeting several interacting signaling pathways simultaneously when attempting to attenuate tumor growth. However, the variable reactions of the different cell lines highlight the necessity to understand the unique molecular aberrations in any tumor. Nevertheless, this combination seems worthy of being tested in vivo.


Assuntos
Everolimo , Lovastatina , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Animais , Sinergismo Farmacológico , Receptores ErbB/genética , Receptores ErbB/metabolismo , Everolimo/agonistas , Everolimo/farmacologia , Células Hep G2 , Humanos , Lovastatina/agonistas , Lovastatina/farmacologia , Camundongos , Camundongos Knockout , Neoplasias/genética , Neoplasias/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Quinases S6 Ribossômicas 70-kDa/genética , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo
12.
Eur Thyroid J ; 4(Suppl 1): 74-80, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26601076

RESUMO

Due to the high variance in available protocols on iodide-131 ((131)I) ablation in rodents, we set out to establish an effective method to generate a thyroid-ablated mouse model that allows the application of the sodium iodide symporter (NIS) as a reporter gene without interference with thyroidal NIS. We tested a range of (131)I doses with and without prestimulation of thyroidal radioiodide uptake by a low-iodine diet and thyroid-stimulating hormone (TSH) application. Efficacy of induction of hypothyroidism was tested by measurement of serum T4 concentrations, pituitary TSHß and liver deiodinase type 1 (DIO1) mRNA expression, body weight analysis, and (99m)Tc-pertechnetate scintigraphy. While 200 µCi (7.4 MBq) (131)I alone was not sufficient to abolish thyroidal T4 production, 500 µCi (18.5 MBq) (131)I combined with 1 week of a low-iodine diet decreased serum concentrations below the detection limit. However, the high (131)I dose resulted in severe side effects. A combination of 1 week of a low-iodine diet followed by injection of bovine TSH before the application of 150 µCi (5.5 MBq) (131)I decreased serum T4 concentrations below the detection limit and significantly increased pituitary TSHß concentrations. The systemic effects of induced hypothyroidism were shown by growth arrest and a decrease in liver DIO1 expression below the detection limit. (99m)Tc-pertechnetate scintigraphy revealed absence of thyroidal (99m)Tc-pertechnetate uptake in ablated mice. In summary, we report a revised protocol for radioiodide ablation of the thyroid gland in the mouse to generate an in vivo model that allows the study of thyroid hormone action using NIS as a reporter gene.

13.
Endocr Relat Cancer ; 22(6): 941-52, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26307023

RESUMO

To improve our understanding of non-genomic, integrin αvß3-mediated thyroid hormone action in tumour stroma formation, we examined the effects of triiodo-l-thyronine (T3), l-thyroxine (T4) and integrin-specific inhibitor tetrac on differentiation, migration and invasion of mesenchymal stem cells (MSCs) that are an integral part of the tumour's fibrovascular network. Primary human bone marrow-derived MSCs were treated with T3 or T4 in the presence of hepatocellular carcinoma (HCC) cell-conditioned medium (CM), which resulted in stimulation of the expression of genes associated with cancer-associated fibroblast-like differentiation as determined by qPCR and ELISA. In addition, T3 and T4 increased migration of MSCs towards HCC cell-CM and invasion into the centre of three-dimensional HCC cell spheroids. All these effects were tetrac-dependent and therefore integrin αvß3-mediated. In a subcutaneous HCC xenograft model, MSCs showed significantly increased recruitment and invasion into tumours of hyperthyroid mice compared to euthyroid and, in particular, hypothyroid mice, while treatment with tetrac almost completely eliminated MSC recruitment. These studies significantly improve our understanding of the anti-tumour activity of tetrac, as well as the mechanisms that regulate MSC differentiation and recruitment in the context of tumour stroma formation, as an important prerequisite for the utilisation of MSCs as gene delivery vehicles.


Assuntos
Inibidores da Angiogênese/farmacologia , Antineoplásicos/farmacologia , Integrina alfaVbeta3/fisiologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Proteínas de Neoplasias/fisiologia , Células Estromais/patologia , Tiroxina/análogos & derivados , Tiroxina/farmacologia , Tri-Iodotironina/farmacologia , Inibidores da Angiogênese/uso terapêutico , Animais , Antineoplásicos/uso terapêutico , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Linhagem da Célula , Movimento Celular , Meios de Cultivo Condicionados , Xenoenxertos , Humanos , Hipertireoidismo/induzido quimicamente , Hipertireoidismo/complicações , Hipotireoidismo/induzido quimicamente , Hipotireoidismo/complicações , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas Experimentais/complicações , Neoplasias Hepáticas Experimentais/patologia , Masculino , Camundongos , Camundongos Nus , Invasividade Neoplásica , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/fisiopatologia , Organismos Livres de Patógenos Específicos , Esferoides Celulares , Tiroxina/uso terapêutico , Tiroxina/toxicidade , Tri-Iodotironina/uso terapêutico , Tri-Iodotironina/toxicidade , Microambiente Tumoral , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Dtsch Med Wochenschr ; 140(16): 1232-6, 2015 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-26261935

RESUMO

Irritable bowel syndrome is a disorder of the gastrointestinal tract with unknown etiology. Recent clinical data support a link between changes in fecal microbiota with decreased biodiversity and the development of irritable bowel syndrome. Whether these changes of the microbiota are caused by the disease or whether they develop during the course of the disease remains unclear. Several studies demonstrated that fecal microbiota transfer (FMT) successfully attenuates Clostridium difficile infection by restoring the disturbed bacterial flora of the gut and case reports suggest that FMT may relief symptoms in patients with irritable bowel syndrome (IBS). Here we report a 47-year-old male patient with longstanding refractory diarrhea predominant IBS, who was successfully treated with a single FMT. The beneficial effect on the patient's symptoms was associated with changes of the stool microbiome. Post-FMT the recipient's microbiome resembled the donor's microbiome.


Assuntos
Terapia Biológica/métodos , Fezes/microbiologia , Síndrome do Intestino Irritável/terapia , Colonoscopia , Diagnóstico Diferencial , Seguimentos , Humanos , Síndrome do Intestino Irritável/diagnóstico , Masculino , Pessoa de Meia-Idade
15.
PLoS One ; 10(8): e0135807, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26288187

RESUMO

BACKGROUND: Currently, limited data of the outcome of inflammatory bowel disease (IBD) in patients after solid organ transplantation (SOT) are available. We aimed to analyze effects of SOT on the IBD course in a large IBD patient cohort. METHODS: Clinical data from 1537 IBD patients were analyzed for patients who underwent SOT (n = 31) between July 2002 and May 2014. Sub-analyses included SOT outcome parameters, IBD activity before and after SOT, and efficacy of IBD treatment. RESULTS: 4.74% of patients with ulcerative colitis (UC) and 0.84% of patients with Crohn's disease (CD) underwent SOT (p = 2.69 x 10(-6), UC vs. CD). 77.4% of patients with SOT underwent liver transplantation (LTx) with tacrolimus-based immunosuppressive therapy after SOT. All LTx were due to primary sclerosing cholangitis (PSC) or PSC overlap syndromes. Six patients (19.4%) required renal transplantation and one patient (3.2%) heart transplantation. A survival rate of 83.9% after a median follow-up period of 103 months was observed. Before SOT, 65.0% of patients were in clinical remission and 5 patients received immunosuppressive therapy (16.1%). After SOT, 61.0% of patients were in remission (p = 1.00 vs. before SOT) and 29.0% required IBD-specific immunosuppressive or anti-TNF therapy (p = 0.54 vs. before SOT). 42.9% of patients with worsening of IBD after SOT were at higher risk of needing steroid therapy for increased IBD activity (p = 0.03; relative risk (RR): 10.29; 95% CI 1.26-84.06). Four patients (13.0%) needed anti-TNF therapy after SOT (response rate 75%). CONCLUSIONS: SOT was more common in UC patients due to the higher prevalence of PSC-related liver cirrhosis in UC. Despite mainly tacrolimus-based immunosuppressive regimens, outcome of SOT and IBD was excellent in this cohort. In this SOT cohort, concomitant immunosuppressive therapy due to IBD was well tolerated.


Assuntos
Colite Ulcerativa/tratamento farmacológico , Doença de Crohn/tratamento farmacológico , Transplante de Coração/efeitos adversos , Transplante de Rim/efeitos adversos , Transplante de Fígado/efeitos adversos , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Adulto , Idoso , Colite Ulcerativa/patologia , Doença de Crohn/patologia , Feminino , Humanos , Terapia de Imunossupressão , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade , Taxa de Sobrevida , Tacrolimo/uso terapêutico , Resultado do Tratamento
16.
Oncotarget ; 6(26): 22167-78, 2015 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-26259250

RESUMO

Tivantinib, a c-MET inhibitor, is investigated as a second-line treatment of HCC. It was shown that c-MET overexpression predicts its efficacy. Therefore, a phase-3 trial of tivantinib has been initiated to recruit "c-MET-high" patients only. However, recent evidence indicates that the anticancer activity of tivantinib is not due to c-MET inhibition, suggesting that c-MET is a predictor of response to this compound rather than its actual target. By assessing the mechanisms underlying the anticancer properties of tivantinib we showed that this agent causes apoptosis and cell cycle arrest by inhibiting the anti-apoptotic molecules Mcl-1 and Bcl-xl, and by increasing Cyclin B1 expression regardless of c-MET status. However, we found that tivantinib might antagonize the antiapoptotic effects of c-MET activation since HGF enhanced the expression of Mcl-1 and Bcl-xl. In summary, we show that the activity of tivantinib is independent of c-MET and describe Mcl-1, Bcl-xl and Cyclin B1 as effectors of its antineoplastic effects in HCC cells. We suggest that the predictive effect of c-MET expression in part reflects the c-MET-driven overexpression of Mcl-1 and Bcl-xl in c-MET-high patients and that these molecules are considered as possible response predictors.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-met/metabolismo , Pirrolidinonas/farmacologia , Quinolinas/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Colangiocarcinoma/tratamento farmacológico , Colangiocarcinoma/metabolismo , Colangiocarcinoma/patologia , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Ciclina B1/metabolismo , Células Hep G2 , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Proteína de Sequência 1 de Leucemia de Células Mieloides/biossíntese , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Proteína bcl-X/metabolismo
17.
PLoS One ; 10(7): e0116044, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26147989

RESUMO

BACKGROUND: A previous study suggested an association of the single nucleotide polymorphism (SNP) rs72796353 (IVS4+10 A>C) in the NOD2 gene with susceptibility to Crohn's disease (CD). However, this finding has not been confirmed. Given that NOD2 variants still represent the most important predictors for CD susceptibility and phenotype, we evaluated the association of rs72796353 with inflammatory bowel disease (IBD) susceptibility and the IBD phenotype. METHODOLOGY: Genomic DNA from 2256 Caucasians, including 1073 CD patients, 464 patients with ulcerative colitis (UC), and 719 healthy controls, was genotyped for the NOD2 SNP rs72796353 and the three main CD-associated NOD2 mutations rs2066844, rs2066845, and rs2066847. Subsequently, IBD association and genotype-phenotype analyses were conducted. RESULTS: In contrast to the strong associations of the NOD2 SNPs rs2066844 (p=3.51 x 10(-3)), rs2066845 (p=1.54 x 10(-2)), and rs2066847 (p=1.61 x 10(-20)) with CD susceptibility, no significant association of rs72796353 with CD or UC susceptibility was found. However, in CD patients without the three main CD-associated NOD2 mutations, rs72796353 was significantly associated with the development of perianal fistulas (p=2.78 x 10(-7), OR 5.27, [95% CI 2.75-10.12] vs. NOD2 wild-type carriers). CONCLUSION/SIGNIFICANCE: Currently, this study represents the largest genotype-phenotype analysis of the impact of the NOD2 variant rs72796353 on the disease phenotype in IBD. Our data demonstrate that in CD patients the IVS4+10 A>C variant is strongly associated with the development of perianal fistulas. This association is particularly pronounced in patients who are not carriers of the three main CD-associated NOD2 mutations, suggesting rs72796353 as additional genetic marker for the CD disease behaviour.


Assuntos
Doença de Crohn/genética , Predisposição Genética para Doença , Mutação , Proteína Adaptadora de Sinalização NOD2/genética , Polimorfismo de Nucleotídeo Único , Fístula Retal/genética , Adulto , Estudos de Casos e Controles , Doença de Crohn/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fístula Retal/complicações
18.
J Transl Med ; 13: 73, 2015 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-25890210

RESUMO

BACKGROUND: The glucagon-like peptide-1 receptor (GLP1R) agonist liraglutide improves glycemic control and reduces body weight of adult type 2 diabetic patients. However, efficacy and safety of liraglutide in adolescents has not been systematically investigated. Furthermore, possible pro-proliferative effects of GLP1R agonists on the endocrine and exocrine pancreas need to be further evaluated. We studied effects of liraglutide in adolescent pigs expressing a dominant-negative glucose-dependent insulinotropic polypeptide receptor (GIPR(dn)) in the beta-cells, leading to a pre-diabetic condition including disturbed glucose tolerance, reduced insulin secretion and progressive reduction of functional beta-cell mass. METHODS: Two-month-old GIPR(dn) transgenic pigs were treated daily with liraglutide (0.6-1.2 mg per day) or placebo for 90 days. Glucose homeostasis was evaluated prior to and at the end of the treatment period by performing mixed meal and intravenous glucose tolerance tests (MMGTT and IVGTT). Finally animals were subjected to necropsy and quantitative-stereological analyses were performed for evaluation of alpha- and beta-cell mass, beta-cell proliferation as well as acinus-cell proliferation. RESULTS: MMGTT at the end of the study revealed 23% smaller area under the curve (AUC) for glucose, a 36% smaller AUC insulin, and improved insulin sensitivity, while IVGTT showed a 15% smaller AUC glucose but unchanged AUC insulin in liraglutide- vs. placebo-treated animals. Liraglutide led to marked reductions in body weight gain (-31%) and food intake (-30%) compared to placebo treatment, associated with reduced phosphorylation of insulin receptor beta (INSRB)/insulin-like growth factor-1 receptor beta (IGF1RB) and protein kinase B (AKT) in skeletal muscle. Absolute alpha- and beta-cell mass was reduced in liraglutide-treated animals, but alpha- and beta-cell mass-to-body weight ratios were unchanged. Liraglutide neither stimulated beta-cell proliferation in the endocrine pancreas nor acinus-cell proliferation in the exocrine pancreas, excluding both beneficial and detrimental effects on the pig pancreas. CONCLUSIONS: Although plasma liraglutide levels of adolescent transgenic pigs treated in our study were higher compared to human trials, pro-proliferative effects on the endocrine or exocrine pancreas or other liraglutide-related side-effects were not observed.


Assuntos
Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Liraglutida/uso terapêutico , Estado Pré-Diabético/tratamento farmacológico , Células Acinares/efeitos dos fármacos , Células Acinares/patologia , Animais , Animais Geneticamente Modificados , Glicemia/metabolismo , Proliferação de Células/efeitos dos fármacos , Tamanho Celular/efeitos dos fármacos , Modelos Animais de Doenças , Comportamento Alimentar/efeitos dos fármacos , Esvaziamento Gástrico/efeitos dos fármacos , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Teste de Tolerância a Glucose , Insulina/metabolismo , Secreção de Insulina , Liraglutida/sangue , Liraglutida/farmacologia , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Tamanho do Órgão/efeitos dos fármacos , Estado Pré-Diabético/patologia , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Aumento de Peso/efeitos dos fármacos
19.
J Nucl Med ; 56(4): 600-6, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25745085

RESUMO

UNLABELLED: The tumor-homing property of mesenchymal stem cells (MSCs) allows targeted delivery of therapeutic genes into the tumor microenvironment. The application of sodium iodide symporter (NIS) as a theranostic gene allows noninvasive imaging of MSC biodistribution and transgene expression before therapeutic radioiodine application. We have previously shown that linking therapeutic transgene expression to induction of the chemokine CCL5/RANTES allows a more focused expression within primary tumors, as the adoptively transferred MSC develop carcinoma-associated fibroblast-like characteristics. Although RANTES/CCL5-NIS targeting has shown efficacy in the treatment of primary tumors, it was not clear if it would also be effective in controlling the growth of metastatic disease. METHODS: To expand the potential range of tumor targets, we investigated the biodistribution and tumor recruitment of MSCs transfected with NIS under control of the RANTES/CCL5 promoter (RANTES-NIS-MSC) in a colon cancer liver metastasis mouse model established by intrasplenic injection of the human colon cancer cell line LS174t. RANTES-NIS-MSCs were injected intravenously, followed by (123)I scintigraphy, (124)I PET imaging, and (131)I therapy. RESULTS: Results show robust MSC recruitment with RANTES/CCL5-promoter activation within the stroma of liver metastases as evidenced by tumor-selective iodide accumulation, immunohistochemistry, and real-time polymerase chain reaction. Therapeutic application of (131)I in RANTES-NIS-MSC-treated mice resulted in a significant delay in tumor growth and improved overall survival. CONCLUSION: This novel gene therapy approach opens the prospect of NIS-mediated radionuclide therapy of metastatic cancer after MSC-mediated gene delivery.


Assuntos
Neoplasias do Colo/radioterapia , Radioisótopos do Iodo/uso terapêutico , Células-Tronco Mesenquimais/citologia , Simportadores/química , Simportadores/genética , Animais , Linhagem Celular Tumoral , Quimiocina CCL5/metabolismo , Feminino , Fibroblastos/metabolismo , Terapia Genética/métodos , Humanos , Neoplasias Hepáticas/radioterapia , Imageamento por Ressonância Magnética , Camundongos , Camundongos Nus , Metástase Neoplásica , Transplante de Neoplasias , Plasmídeos/metabolismo , Tomografia por Emissão de Pósitrons , Cintilografia , Transgenes , Microambiente Tumoral
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...