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1.
Hepatology ; 2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37916976

RESUMO

BACKGROUND AND AIMS: HCC is the most common primary liver tumor, with an increasing incidence worldwide. HCC is a heterogeneous malignancy and usually develops in a chronically injured liver. The NF-κB signaling network consists of a canonical and a noncanonical branch. Activation of canonical NF-κB in HCC is documented. However, a functional and clinically relevant role of noncanonical NF-κB and its downstream effectors is not established. APPROACH AND RESULTS: Four human HCC cohorts (total n = 1462) and 4 mouse HCC models were assessed for expression and localization of NF-κB signaling components and activating ligands. In vitro , NF-κB signaling, proliferation, and cell death were measured, proving a pro-proliferative role of v-rel avian reticuloendotheliosis viral oncogene homolog B (RELB) activated by means of NF-κB-inducing kinase. In vivo , lymphotoxin beta was identified as the predominant inducer of RELB activation. Importantly, hepatocyte-specific RELB knockout in a murine HCC model led to a lower incidence compared to controls and lower maximal tumor diameters. In silico , RELB activity and RELB-directed transcriptomics were validated on the The Cancer Genome Atlas HCC cohort using inferred protein activity and Gene Set Enrichment Analysis. In RELB-active HCC, pathways mediating proliferation were significantly activated. In contrast to v-rel avian reticuloendotheliosis viral oncogene homolog A, nuclear enrichment of noncanonical RELB expression identified patients with a poor prognosis in an etiology-independent manner. Moreover, RELB activation was associated with malignant features metastasis and recurrence. CONCLUSIONS: This study demonstrates a prognostically relevant, etiology-independent, and cross-species consistent activation of a lymphotoxin beta/LTßR/RELB axis in hepatocarcinogenesis. These observations may harbor broad implications for HCC, including possible clinical exploitation.

2.
Gastroenterology ; 159(1): 183-199, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32179094

RESUMO

BACKGROUND & AIMS: Intestinal epithelial homeostasis depends on a tightly regulated balance between intestinal epithelial cell (IEC) death and proliferation. While the disruption of several IEC death regulating factors result in intestinal inflammation, the loss of the anti-apoptotic BCL2 family members BCL2 and BCL2L1 has no effect on intestinal homeostasis in mice. We investigated the functions of the antiapoptotic protein MCL1, another member of the BCL2 family, in intestinal homeostasis in mice. METHODS: We generated mice with IEC-specific disruption of Mcl1 (Mcl1ΔIEC mice) or tamoxifen-inducible IEC-specific disruption of Mcl1 (i-Mcl1ΔIEC mice); these mice and mice with full-length Mcl1 (controls) were raised under normal or germ-free conditions. Mice were analyzed by endoscopy and for intestinal epithelial barrier permeability. Intestinal tissues were analyzed by histology, in situ hybridization, proliferation assays, and immunoblots. Levels of calprotectin, a marker of intestinal inflammation, were measured in intestinal tissues and feces. RESULTS: Mcl1ΔIEC mice spontaneously developed apoptotic enterocolopathy, characterized by increased IEC apoptosis, hyperproliferative crypts, epithelial barrier dysfunction, and chronic inflammation. Loss of MCL1 retained intestinal crypts in a hyperproliferated state and prevented the differentiation of intestinal stem cells. Proliferation of intestinal stem cells in MCL1-deficient mice required WNT signaling and was associated with DNA damage accumulation. By 1 year of age, Mcl1ΔIEC mice developed intestinal tumors with morphologic and genetic features of human adenomas and carcinomas. Germ-free housing of Mcl1ΔIEC mice reduced markers of microbiota-induced intestinal inflammation but not tumor development. CONCLUSION: The antiapoptotic protein MCL1, a member of the BCL2 family, is required for maintenance of intestinal homeostasis and prevention of carcinogenesis in mice. Loss of MCL1 results in development of intestinal carcinomas, even under germ-free conditions, and therefore does not involve microbe-induced chronic inflammation. Mcl1ΔIEC mice might be used to study apoptotic enterocolopathy and inflammatory bowel diseases.


Assuntos
Carcinoma/patologia , Mucosa Intestinal/patologia , Neoplasias Intestinais/patologia , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Animais , Apoptose/genética , Apoptose/imunologia , Carcinogênese/genética , Carcinogênese/imunologia , Carcinogênese/patologia , Carcinoma/diagnóstico , Carcinoma/genética , Modelos Animais de Doenças , Endoscopia , Células Epiteliais/patologia , Humanos , Doenças Inflamatórias Intestinais/imunologia , Doenças Inflamatórias Intestinais/patologia , Mucosa Intestinal/diagnóstico por imagem , Neoplasias Intestinais/diagnóstico , Neoplasias Intestinais/genética , Camundongos , Camundongos Transgênicos , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética
3.
Gastroenterology ; 156(4): 1190-1205.e14, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30445013

RESUMO

BACKGROUND & AIMS: Cholangiocyte proliferation and ductular reaction contribute to the onset and progression of liver diseases. Little is known about the role of the transcription factor nuclear factor-κB (NF-κB) in this process. We investigated the activities of the RELB proto-oncogene NF-κB subunit in human cholangiocytes and in mouse models of liver disease characterized by a ductular reaction. METHODS: We obtained liver tissue samples from patients with primary sclerosing cholangitis, primary biliary cholangitis, hepatitis B or C virus infection, autoimmune hepatitis, alcoholic liver disease, or without these diseases (controls) from a tissue bank in Germany. Tissues were analyzed by immunohistochemistry for levels of RELB and lymphotoxin ß (LTB). We studied mice with liver parenchymal cell (LPC)-specific disruption of the cylindromatosis (CYLD) lysine 63 deubiquitinase gene (Cyld), with or without disruption of Relb (CyldΔLPC mice and Cyld/RelbΔLPC mice) and compared them with C57BL/6 mice (controls). Mice were fed 5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) or standard chow diets to induce biliary injury or were given injections of CCl4 to induce non-cholestatic liver fibrosis. Liver tissues were analyzed by histology, immunohistochemistry, immunoblots, in situ hybridization, and quantitative real-time polymerase chain reaction. Cholangiocytes were isolated from normal human liver, incubated with LTB receptor agonist, and transfected with small interfering RNAs to knock down RELB. RESULTS: In liver tissues from patients with primary sclerosing cholangitis, primary biliary cholangitis, chronic infection with hepatitis B or C virus, autoimmune hepatitis, or alcoholic liver disease, we detected increased nuclear translocation of RELB and increased levels of LTB in cholangiocytes that formed reactive bile ducts compared with control liver tissues. Human cholangiocytes, but not those with RELB knockdown, proliferated with exposure to LTB. The phenotype of CyldΔLPC mice, which included ductular reaction, oval cell activation, and biliary fibrosis, was completely lost from Cyld/RelbΔLPC mice. Compared with livers from control mice, livers from CyldΔLPC mice (but not Cyld/RelbΔLPC mice) had increased levels of mRNAs encoding cytokines (LTB; CD40; and tumor necrosis factor superfamily [TNFSF] members TNFSF11 [RANKL], TNFSF13B [BAFF], and TNFSF14 [LIGHT]) produced by reactive cholangiocytes. However, these strains of mice developed similar levels of liver fibrosis in response to CCl4 exposure. CyldΔLPC mice and Cyld/RelbΔLPC mice had improved liver function on the DDC diet compared with control mice fed the DDC diet. CONCLUSION: Reactive bile ducts in patients with chronic liver diseases have increased levels of LTB and nuclear translocation of RELB. RELB is required for the ductular reaction and development of biliary fibrosis in CyldΔLPC mice. Deletion of RELB and CYLD from LPCs protects mice from DDC-induced cholestatic liver fibrosis.


Assuntos
Ductos Biliares/metabolismo , Ductos Biliares/patologia , Colangite Esclerosante/metabolismo , Citocinas/genética , Hepatopatias/metabolismo , Fator de Transcrição RelB/metabolismo , Adolescente , Adulto , Idoso , Animais , Tetracloreto de Carbono , Núcleo Celular , Proliferação de Células , Células Cultivadas , Cisteína Endopeptidases/genética , Enzima Desubiquitinante CYLD , Dicarbetoxi-Di-Hidrocolidina , Células Epiteliais/metabolismo , Feminino , Fibrose , Técnicas de Silenciamento de Genes , Humanos , Fígado/patologia , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Receptor beta de Linfotoxina/agonistas , Linfotoxina-beta/metabolismo , Masculino , Camundongos , Pessoa de Meia-Idade , Tecido Parenquimatoso/patologia , Transporte Proteico , Proto-Oncogene Mas , RNA Mensageiro/metabolismo , Fator de Transcrição RelB/genética , Adulto Jovem
4.
Int J Mol Sci ; 21(3)2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-32046105

RESUMO

Autophagy is a catabolic process that enables cells to degrade obsolete content and refuel energy depots. In colorectal cancer (CRC) autophagy has been shown to promote tumorigenesis through energy delivery in the condition of uncontrolled proliferation. With this study, we aimed at evaluating whether autophagy sustains CRC cell viability and if it impacts therapy resistance. Initially, a colorectal cancer tissue micro array, containing mucosa (n = 10), adenoma (n = 18) and adenocarcinoma (n = 49) spots, was stained for expression of essential autophagy proteins LC3b, Atg7, p62 and Beclin-1. Subsequently, central autophagy proteins were downregulated in CRC cells using siRNA technology. Viability assays, flow cytometry and immunoblotting were performed and three-dimensional cell culture was utilized to study autophagy in a tissue mimicking environment. In our study we found an upregulation of Atg7 in CRC. Furthermore, we identified Atg7 as crucial factor within the autophagy network for CRC cell viability. Its disruption induced cell death via triggering apoptosis and in combination with conventional chemotherapy it exerted synergistic effects in inducing CRC cell death. Cell death was strictly dependent on nuclear LC3b, since simultaneous knockdown of Atg7 and LC3b completely restored viability. This study unravels a novel cell death preventing function of Atg7 in interaction with LC3b, thereby unmasking a promising therapeutic target in CRC.


Assuntos
Adenocarcinoma/metabolismo , Apoptose , Proteína 7 Relacionada à Autofagia/metabolismo , Neoplasias Colorretais/metabolismo , Resistencia a Medicamentos Antineoplásicos , Adenocarcinoma/genética , Antineoplásicos/farmacologia , Autofagia , Proteína 7 Relacionada à Autofagia/genética , Proteína Beclina-1/genética , Proteína Beclina-1/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Neoplasias Colorretais/genética , Fluoruracila/farmacologia , Células HT29 , Humanos , Irinotecano/farmacologia , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo
6.
Breast Cancer Res Treat ; 173(3): 585-596, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30374681

RESUMO

PURPOSE: Recent studies have emphasized a key role for the anti-apoptotic Bcl-2 family member Mcl-1 in conferring tumor cell survival and drug resistance in breast cancer (BC). Mcl-1 inhibitors, such as the BH3-mimetic EU-5346, therefore represent an exciting new class of targeting agents and are a current focus of widespread cancer-drug development efforts. METHODS: ONCOMINE analysis was utilized to compare expression profiles of Bcl-2 family members across all major BC subgroups. Potential toxicities of EU-5346 were evaluated using iPS-generated cardiomyocytes, blood cells and astrocytes. The anti-BC cell activity of EU-5346-based therapies was evaluated using [3H]-thymidine uptake and spheroid-forming assays as well as immunoblotting and the Chou-Talalay method. Protein level-based activity of EU-5346, the specific anti-Bcl-2 inhibitor ABT-199 and the specific anti-Bcl-xL inhibitor WEHI-539 was verified in Mcl-1Δ/null versus Mcl-1wt/wt MEFs. RESULTS: We previously demonstrated significant anti-tumor activity of EU-5346 in all BC subtypes. Our present results go further and suggest that EU-5346 may induce limited adverse events such as cardiotoxicity, hematotoxicity, and neurotoxicity, frequently observed with other BH3 mimetics. As demonstrated by our mathematical scoring model, the prediction of EU-5643-induced IC50 not only relies on the protein level of Mcl-1 but also on Bak, Bim, and Noxa. Synergistic anti-BC activity of low-dose EU-5346 with the BH3 mimetics ABT-199 or WEHI-539 was observed only in those BC cells expressing Bcl-2 or Bcl-xL, respectively. Similarly, when combined with tamoxifen or trastuzumab, low-dose EU-5346 induced significant anti-BC activity in hormone receptor positive or Her2-positive BC cells, respectively. Finally, EU-5346 in combination with paclitaxel induced synergistic anti-BC activity in both paclitaxel-sensitive and paclitaxel-resistant TNBC cells. CONCLUSION: These data strongly support the further clinical development of EU-5346 to improve BC patient survival.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/metabolismo , Proteína de Sequência 1 de Leucemia de Células Mieloides/antagonistas & inibidores , Antineoplásicos/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Cardiotoxicidade , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Combinação de Medicamentos , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Terapia de Alvo Molecular , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína bcl-X/genética , Proteína bcl-X/metabolismo
7.
Hepatology ; 65(6): 2074-2089, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28108987

RESUMO

Incidence and prevalence of inflammatory liver diseases has increased over the last years, but therapeutic options are limited. Pregnancy induces a state of immune tolerance, which can result in spontaneous improvement of clinical symptoms of certain autoimmune diseases including autoimmune hepatitis (AIH). We investigated the immune-suppressive mechanisms of the human pregnancy hormone, chorionic gonadotropin (hCG), in the liver. hCG signaling activates silent mating type information regulation 2 homolog 1 (SIRT1), which deacetylates forkhead box o3 (FOXO3a), leading to repression of proapoptotic gene expression, because the immunosuppressive consequence attributed to the absence of caspase-3 activity of hepatocellular interleukin 16 (IL-16) is no longer processed and released. Thus, serum levels of IL-16, a key chemotactic factor for CD4+ lymphocytes, were reduced and migration to injured hepatocytes prevented. Furthermore, elevated IL-16 levels are found in the sera from patients with AIH, hepatitis B virus, hepatitis C virus, and nonalcoholic steatohepatitis. CONCLUSION: Here, we report that hCG regulates the SIRT1/FOXO3a axis in hepatocytes, resulting in immune suppression by attenuating caspase-3-dependent IL-16 processing and release, which concomitantly prevents autoaggressive T-cell infiltration of the liver. Considering the low toxicity profile of hCG in humans, interrupting the inflammatory cycle by hCG opens new perspectives for therapeutic intervention of inflammatory liver diseases. (Hepatology 2017;65:2074-2089).


Assuntos
Gonadotropina Coriônica/farmacologia , Proteína Forkhead Box O3/efeitos dos fármacos , Hepatite Autoimune/patologia , Transdução de Sinais/efeitos dos fármacos , Sirtuína 1/efeitos dos fármacos , Animais , Linfócitos T CD4-Positivos/metabolismo , Caspase 3/metabolismo , Células Cultivadas , Modelos Animais de Doenças , Feminino , Proteína Forkhead Box O3/metabolismo , Hepatite Autoimune/imunologia , Hepatócitos/efeitos dos fármacos , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Distribuição Aleatória , Sensibilidade e Especificidade , Sirtuína 1/metabolismo
8.
Breast Cancer Res ; 18(1): 26, 2016 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-26921175

RESUMO

BACKGROUND: Molecular mechanisms leading to the adaptation of breast cancer (BC) cells to hypoxia are largely unknown. The anti-apoptotic Bcl-2 family member myeloid cell leukemia-1 (Mcl-1) is frequently amplified in BC; and elevated Mcl-1 levels have been correlated with poor prognosis. Here we investigated the pathophysiologic role of Mcl-1 in Her2-positive BC cells under hypoxic conditions. METHODS: RNA interference and a novel small molecule inhibitor, EU-5346, were used to examine the role of Mcl-1 in Her2-positive BC cell lines and primary BC cells (sensitive or intrinsically resistant to Her2 inhibitors) under hypoxic conditions (using a hypoxic incubation chamber). Mechanisms-of-action were investigated by RT-PCR, mitochondrial isolation, as well as immunoprecipitation/blotting analysis, and microscopy. The specificity against Mcl-1 of the novel small molecule inhibitor EU5346 was verified in Mcl-1(Δ/null) versus Mcl-1(wt/wt) Murine Embryonic Fibroblasts (MEFs). Proliferation, survival, and spheroid formation were assessed in response to Mcl-1 and Her2 inhibition. RESULTS: We demonstrate for a strong correlation between high Mcl-1 protein levels and hypoxia, predominantly in Her2-positive BC cells. Surprisingly, genetic depletion of Mcl-1 decreased Her2 and Hif-1α levels followed by inhibition of BC cell survival. In contrast, Mcl-1 protein levels were not downregulated after genetic depletion of Her2 indicating a regulatory role of Mcl-1 upstream of Her2. Indeed, Mcl-1 and Her2 co-localize within the mitochondrial fraction and form a Mcl-1/Her2- protein complex. Similar to genetically targeting Mcl-1 the novel small molecule Mcl-1 inhibitor EU-5346 induced cell death and decreased spheroid formation in Her2-positive BC cells. Of interest, EU-5346 induced ubiquitination of Mcl-1- bound Her2 demonstrating a previously unknown role for Mcl-1 to stabilize Her2 protein levels. Importantly, targeting Mcl-1 was also active in Her2-positive BC cells resistant to Her2 inhibitors, including a brain-primed Her2-positive cell line. CONCLUSION: Our data demonstrate a critical role of Mcl-1 in Her2-positive BC cell survival under hypoxic conditions and provide the preclinical framework for the therapeutic use of novel Mcl-1- targeting agents to improve patient outcome in BC.


Assuntos
Neoplasias da Mama/genética , Hipóxia Celular/genética , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Receptor ErbB-2/genética , Animais , Apoptose/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Proteína de Sequência 1 de Leucemia de Células Mieloides/biossíntese , Interferência de RNA , Transdução de Sinais/genética
9.
Alcohol Clin Exp Res ; 40(10): 2094-2101, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27581253

RESUMO

BACKGROUND: Chronic alcohol consumption is a risk factor for colorectal cancer. The mechanisms by which ethanol (EtOH) exerts its carcinogenic effect on the colorectal mucosa are not clear and may include oxidative stress with the action of reactive oxygen species (ROS) generated through EtOH metabolism via cytochrome P4502E1 (CYP2E1) leading to carcinogenic etheno-DNA adducts. ROS may also induce apoptosis. However, the effect of chronic EtOH consumption on CYP2E1, etheno-DNA adducts as well as anti-apoptotic proteins in the colorectal mucosa of heavy drinkers without colorectal inflammation is still not known. METHODS: Rectal biopsies from 32 alcoholics (>60 g EtOH/d) and from 12 controls (<20 g EtOH/d) were histologically examined, and immunohistochemistry for CYP2E1 and etheno-DNA adducts was performed. Apoptosis (cleaved PARP) as well as anti-apoptotic proteins including Bcl-xL , Bcl-2, and Mcl-1 were immunohistochemically determined. RESULTS: No significant difference in mucosal CYP2E1 or etheno-DNA adducts was observed between alcoholics and control patients. However, CYP2E1 and etheno-DNA adducts correlated significantly when both groups were combined (p < 0.001). In addition, although apoptosis was found not to be significantly affected by EtOH, the anti-apoptotic protein Mcl-1, but neither Bcl-xL nor Bcl-2, was found to be significantly increased in heavy drinkers as compared to controls (p = 0.014). CONCLUSIONS: Although colorectal CYP2E1 was not found to be significantly increased in alcoholics, CYP2E1 correlated overall with the level of etheno-DNA adducts in the colorectal mucosa, which identifies CYP2E1 as an important factor in colorectal carcinogenesis. Most importantly, however, is the up-regulation of the anti-apoptotic protein Mcl-1 in heavy drinkers counteracting apoptosis and possibly stimulating cancer development.


Assuntos
Alcoolismo/metabolismo , Carcinogênese/induzido quimicamente , Citocromo P-450 CYP2E1/metabolismo , Adutos de DNA/metabolismo , Etanol/toxicidade , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Reto/metabolismo , Idoso , Alcoolismo/complicações , Apoptose , Proteínas Reguladoras de Apoptose/metabolismo , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reto/efeitos dos fármacos
10.
BMC Cancer ; 15: 919, 2015 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-26585594

RESUMO

BACKGROUND: Colorectal cancer is the third most common malignancy in humans and novel therapeutic approaches are urgently needed. Autophagy is an evolutionarily highly conserved cellular process by which cells collect unnecessary organelles or misfolded proteins and subsequently degrade them in vesicular structures in order to refuel cells with energy. Dysregulation of the complex autophagy signaling network has been shown to contribute to the onset and progression of cancer in various models. The Bcl-2 family of proteins comprises central regulators of apoptosis signaling and has been linked to processes involved in autophagy. The antiapoptotic members of the Bcl-2 family of proteins have been identified as promising anticancer drug targets and small molecules inhibiting those proteins are in clinical trials. METHODS: Flow cytometry and colorimetric assays were used to assess cell growth and cell death. Long term 3D cell culture was used to assess autophagy in a tissue mimicking environment in vitro. RNA interference was applied to modulate autophagy signaling. Immunoblotting and q-RT PCR were used to investigate autophagy signaling. Immunohistochemistry and fluorescence microscopy were used to detect autophagosome formation and autophagy flux. RESULTS: This study demonstrates that autophagy inhibition by obatoclax induces cell death in colorectal cancer (CRC) cells in an autophagy prone environment. Here, we demonstrate that pan-Bcl-2 inhibition by obatoclax causes a striking, late stage inhibition of autophagy in CRC cells. In contrast, ABT-737, a Mcl-1 sparing Bcl-2 inhibitor, failed to interfere with autophagy signaling. Accumulation of p62 as well as Light Chain 3 (LC3) was observed in cells treated with obatoclax. Autophagy inhibition caused by obatoclax is further augmented in stressful conditions such as starvation. Furthermore, our data demonstrate that inhibition of autophagy caused by obatoclax is independent of the essential pro-autophagy proteins Beclin-1, Atg7 and Atg12. CONCLUSIONS: The objective of this study was to dissect the contribution of Bcl-2 proteins to autophagy in CRC cells and to explore the potential of Bcl-2 inhibitors for autophagy modulation. Collectively, our data argue for a Beclin-1 independent autophagy inhibition by obatoclax. Based on this study, we recommend the concept of autophagy inhibition as therapeutic strategy for CRC.


Assuntos
Antineoplásicos/farmacologia , Autofagia/efeitos dos fármacos , Neoplasias Colorretais/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Pirróis/farmacologia , Compostos de Bifenilo/farmacologia , Técnicas de Cultura de Células , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Células HT29 , Humanos , Indóis , Nitrofenóis/farmacologia , Piperazinas/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sulfonamidas/farmacologia
11.
Liver Int ; 35(2): 591-600, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25290314

RESUMO

BACKGROUND & AIMS: The BCLC-staging system is used to facilitate treatment decisions in patients with hepatocellular carcinoma (HCC). Owing to the observed clinical heterogeneity of the intermediate stage BCLC-B, a subclassification was proposed taking Child-Pugh score and extended criteria for transplantation into account. Analysis of the prognostic significance of a proposed subclassification of the BCLC-B score in a European cohort of HCC patients. METHODS: Eight hundred and eighty four consecutive HCC patients were retrospectively analysed. Patients with stage BCLC-B were grouped according to the proposed subclassification. Baseline patient and tumour characteristics, therapy and overall survival were analysed. RESULTS: Two hundred and fifty four patients with stage BCLC-B were classified as B1/B2/B3 and B4 in 16.1/56.7/7.9 and 19.3%. OS compared between adjacent subgroups (B1 vs. B2, B2 vs. B3, B3 vs. B4) did not reach statistical significance. Groupwise comparison showed significant differences between B1 vs. B3 (P = 0.035), B1 vs. B4 (P = 0.006) and B2 vs. B4 (P < 0.0001). OS was significantly improved in patients undergoing OLT (P < 0.0001). Cox regression showed no significant influence of the BCLC-B substage on survival. CONCLUSIONS: No significant survival differences between subgroups were found in the retrospective analysis. We could not confirm the BCLC-B subclassification to be prognostically meaningful in our cohort. As liver function and therapy influenced survival in this study, a more refined BCLC-B subclassification has the potential to be a useful tool to better stratify treatment decisions. Further studies in larger collectives with homogenous staging and treatment strategies are warranted to confirm the prognostic significance of the proposed subclassifications.


Assuntos
Carcinoma Hepatocelular/classificação , Carcinoma Hepatocelular/epidemiologia , Neoplasias Hepáticas/classificação , Neoplasias Hepáticas/epidemiologia , Estadiamento de Neoplasias/métodos , Carcinoma Hepatocelular/diagnóstico , Europa (Continente) , Humanos , Neoplasias Hepáticas/diagnóstico , Prognóstico , Análise de Regressão , Estudos Retrospectivos , Estatísticas não Paramétricas , Análise de Sobrevida
12.
Liver Int ; 35(5): 1615-22, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25369181

RESUMO

BACKGROUNDS & AIMS: Reports of hepatobiliary malignancies in Wilson disease are sparse. The aim of this study was to evaluate hepatobiliary malignancies in Wilson disease patients concerning the clinical course of tumour disease and pathological analysis of tumour tissue. METHODS: Multicenter cohort study of patients with confirmed diagnosis of Wilson disease treated at the Second Department of Neurology, Institute of Psychiatry and Neurology, Warsaw, Poland, the university hospitals Heidelberg, Duesseldorf and Dresden, Germany, and the Department of Hepatology, University Leuven, Belgium. Occurrence, treatment and outcome of hepatobiliary tumours were analysed retrospectively. RESULTS: Of a total of 1186 patients, fourteen developed hepatobiliary malignancies. Eight were hepatocellular carcinomas (HCC) and six were intrahepatic cholangiocellular carcinomas (ICC). The prevalence of hepatobiliary malignancies in the cohort was 1.2% and the incidence was 0.28 per 1000 person years. Pathological analysis of tumour material showed no abnormal copper concentration. CONCLUSIONS: The rate of hepatobiliary malignancies in Wilson disease is very low, even in cirrhotic patients. As a result of the relevant number of ICC in addition to HCC histological analysis through surgical resection or biopsy should be mandatory when a suspect liver lesion is detected. The influence of copper depletion from Wilson disease-specific medical treatment on tumour activity remains to be elucidated.


Assuntos
Neoplasias dos Ductos Biliares/epidemiologia , Carcinoma Hepatocelular/epidemiologia , Colangiocarcinoma/epidemiologia , Degeneração Hepatolenticular/epidemiologia , Neoplasias Hepáticas/epidemiologia , Adulto , Bélgica , Ductos Biliares Intra-Hepáticos/patologia , Biópsia , Cobre/metabolismo , Feminino , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Polônia , Estudos Retrospectivos , Adulto Jovem
13.
J Clin Gastroenterol ; 49(5): 438-47, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25014239

RESUMO

GOALS: The aim of this study was to assess the long-term outcome of primary biliary cirrhosis (PBC) patients and to test the clinical value of various outcome models, such as the Mayo Risk Score (MRS), in a large single-center cohort in Germany. BACKGROUND: PBC is a chronic autoimmune liver disease with a female gender predominance and a peak incidence in the fifth decade of life. PBC is characterized by portal inflammation and immune-mediated destruction of intrahepatic bile ducts in liver histology and the presence of antimitochondrial antibodies in the serum of nearly 95% of patients. In 5% to 20% of patients an overlap syndrome with autoimmune hepatitis (AIH) is diagnosed. Ursodeoxycholic acid is widely accepted as the standard medical treatment. STUDY: A total of 204 patients with PBC or PBC/AIH were retrospectively analyzed with regard to their clinical, biochemical, serological, and histologic features. PBC was diagnosed on the basis of the American Association for the Study of Liver Diseases criteria. Specific PBC scores, such as the MRS, the European and the Yale model, as well as nonspecific scores such as the Child-Pugh, the Model for End-stage Liver Disease, and Aspartate Aminotransferase to Platelet Ratio Index score were analyzed for their utility to predict the clinical outcome of patients. RESULTS: One hundred eighty-four patients with PBC alone and 20 with primary biliary cirrhosis/autoimmune hepatitis overlap were followed up for an average of 7.0 (range, 0.5 to 33.2) years. Importantly, baseline values of serum bilirubin, alkaline phosphatase, immunoglobulin M (IgM) and IgG, as well as antimitochondrial antibodies titers did not allow in properly predicting patient's outcome. The MRS proved clinical applicability. Patients with an R-value <6 did not develop liver-related complications. The Aspartate Aminotransferase to Platelet Ratio Index score had a significant correlation with the histologic degree of liver fibrosis, with limited value of scores between 1.0 and 1.5. Patients with a Model for End-stage Liver Disease score ≥8 (n=17) had a significantly higher risk to undergo liver transplantation or liver-related death. Outcome was less favorable than predicted by the European model. All scores showed low positive predictive values, limiting their applicability in clinical practice. CONCLUSIONS: Herein, we demonstrate that clinical risk scores in PBC should be interpreted with care. The MRS proved to be helpful to predict a favorable outcome. Novel approaches to predict outcome are needed to identify patients who may benefit from alternative, intensified treatment regimens.


Assuntos
Hepatite Autoimune/sangue , Hepatite Autoimune/patologia , Cirrose Hepática Biliar/sangue , Cirrose Hepática Biliar/patologia , Índice de Gravidade de Doença , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Fosfatase Alcalina/sangue , Aspartato Aminotransferases/sangue , Bilirrubina/sangue , Criança , Colagogos e Coleréticos/uso terapêutico , Feminino , Seguimentos , Hepatite Autoimune/complicações , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Cirrose Hepática Biliar/complicações , Cirrose Hepática Biliar/terapia , Transplante de Fígado , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Ácido Ursodesoxicólico/uso terapêutico , Adulto Jovem
14.
Cancer Immunol Immunother ; 63(12): 1273-84, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25164876

RESUMO

Immunotherapeutic approaches are emerging as promising new treatment options for patients with solid cancers. The host immune system in cancer patients is dysfunctional due to a number of reasons. The level of immunosuppression is variable at the time of diagnosis and depends on the particular cancer entity, stage, and prior anti-cancer therapies. For many cancer entities, the immune alterations of the respective patient population have not been further characterized even though a patient's immunophenotype may be prognostic for the course of the disease or predictive for clinical/biological response to immunotherapy. In this study, we used flow cytometry to determine the phenotype of peripheral blood mononuclear cells (PBMCs) from 30 patients with heavily pre-treated, advanced adenocarcinoma of the stomach and gastro-esophageal junction. The frequencies and activation status of relevant immune effector populations were determined in PBMCs and compared to those of healthy individuals. This report provides comprehensive immune phenotyping data of a patient population with a high medical need.


Assuntos
Adenocarcinoma/sangue , Junção Esofagogástrica/patologia , Leucócitos Mononucleares/imunologia , Neoplasias Gástricas/sangue , Adenocarcinoma/imunologia , Adulto , Idoso , Feminino , Humanos , Imunoterapia , Masculino , Pessoa de Meia-Idade , Prognóstico , Neoplasias Gástricas/imunologia
15.
BMC Cancer ; 14: 174, 2014 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-24612620

RESUMO

BACKGROUND: Despite introduction of effective chemotherapy protocols, it has remained uncertain, if patients with colorectal cancer (CRC) liver metastases should receive adjuvant therapy. Clinical or molecular predictors may help to select patients at high risk for disease recurrence and death who obtain a survival advantage by adjuvant chemotherapy. METHODS: A total of 297 patients with potentially curative resection of CRC liver metastases were analyzed. These patients had no neoadjuvant therapy, no extrahepatic disease and negative resection margins. The primary endpoint was overall survival. Patients' risk status was evaluated using the Memorial Sloan-Kettering Cancer Center clinical risk score (MSKCC-CRS). Multivariable analyses were performed using Cox proportional hazard models. RESULTS: A total of 137 (43%) patients had a MSKCC-CRS > 2. Adjuvant chemotherapy was administered to 116 (37%) patients. Patients who received adjuvant chemotherapy were of younger age (p = 0.03) with no significant difference in the presence of multiple metastases (p = 0.72) or bilobar metastases (p = 0.08). On multivariate analysis adjuvant chemotherapy was associated with improved survival in the entire cohort (Hazard ratio 0.69; 95% confidence interval 0.69-0.98). It improved survival markedly in high-risk patients with a MSKCC-CRS > 2 (HR 0.40; 95% CI 0.23-0.69), whereas it was of no benefit in patients with a MSKCC-CRS ≤ 2 (HR 0.90; 95% CI 0.57-1.43). CONCLUSIONS: The MSKCC-CRS offers a tool to select patients for adjuvant therapy after resection of CRC liver metastases. Validation in independent patient cohorts is required.


Assuntos
Antineoplásicos/uso terapêutico , Quimioterapia Adjuvante , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/secundário , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Camptotecina/análogos & derivados , Camptotecina/uso terapêutico , Quimioterapia Adjuvante/métodos , Neoplasias Colorretais/patologia , Neoplasias Colorretais/cirurgia , Feminino , Fluoruracila/uso terapêutico , Humanos , Leucovorina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Compostos Organoplatínicos/uso terapêutico , Estudos Prospectivos , Análise de Sobrevida , Resultado do Tratamento
16.
Pancreatology ; 14(6): 546-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25280592

RESUMO

BACKGROUND/OBJECTIVES: Solid pseudopapillary neoplasms of the pancreas (SPN) are rare tumors. For patients with unresectable liver metastases of SPN, no standard treatment has been defined so far. Here we report a case of a 40-year-old woman with SPN and metastases confirmed to the liver, and disease progression in the liver after primary tumor resection and chemotherapy with gemcitabine and cisplatin. METHODS: Chemosaturation with percutaneous hepatic perfusions is a minimally invasive, repeatable regional therapy which delivers chemotherapy directly to the liver while limiting systemic toxicity. As an individual treatment approach, the patient was treated with chemosaturation with percutaneous hepatic perfusions of melphalan. RESULTS: The procedure was performed twice within 8 weeks after which the liver metastases showed a marked reduction in size and vascularization (partial response). Grade 3 leukopenia after the second procedure was managed effectively with granulocyte colony-stimulating factor. No other toxicities were observed. Ten months after initiating treatment, the patient had a good performance status and remained stable. CONCLUSIONS: For SPN with unresectable liver metastases and progression despite systemic treatment, repeat chemosaturation with high-dose melphalan may also offer an effective regional treatment option.


Assuntos
Antineoplásicos Alquilantes/uso terapêutico , Carcinoma Papilar/tratamento farmacológico , Carcinoma Papilar/secundário , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/secundário , Melfalan/uso terapêutico , Neoplasias Pancreáticas/patologia , Adulto , Antimetabólitos Antineoplásicos/uso terapêutico , Antineoplásicos/uso terapêutico , Carcinoma Papilar/patologia , Cisplatino/uso terapêutico , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapêutico , Feminino , Humanos , Neoplasias Hepáticas/patologia , Resultado do Tratamento , Gencitabina
17.
J Clin Gastroenterol ; 48(3): 279-89, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24045276

RESUMO

GOALS: The aim of this study was to analyze clinical presentation, course of disease, and management of patients with hepatocellular carcinoma (HCC) in a German referral center between 1998 and 2009. BACKGROUND: HCC is a rare tumor in Germany, but its incidence has increased over the last 30 years. New therapies such as chemoembolization with drug-eluting beads, selective internal radiotherapy, and sorafenib were introduced recently; however, the impact on clinical management and overall survival (OS) is unclear. STUDY: In this retrospective analysis, 1066 patients with HCC, separated into two 6-year periods (n=385; 1998 to 2003 and n=681; 2004 to 2009) were evaluated. RESULTS: The number of patients presenting each year (64 vs. 114 per year), with an age over 80 years or with nonalcoholic steatohepatitis increased significantly between periods. The main risk factors were alcoholic liver disease in 51.7%, chronic hepatitis C virus in 28.2%, and chronic hepatitis B virus in 13.4% of patients with liver cirrhosis and HCC. Patients presented with more advanced tumor stages and with worse liver function in period 2. The majority (61.6%) of patients received local treatment over a spectrum of Barcelona Clinic Liver-Cancer (BCLC) stages, whereas systemic therapy was offered to a minority (8.8%) and limited to BCLC stage C patients only. OS decreased in BCLC stage A and D and improved in BCLC stage B and C and decreased for all patients from 16.5 to 15.3 months between periods. CONCLUSIONS: No improvement of OS was observed when comparing time periods, partly because of the more advanced stage of HCC and because of the increasing age in the second time period. Improved and new therapeutic options and the intensification of surveillance programs are likely to increase survival of HCC patients in the future.


Assuntos
Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/terapia , Oncologia/tendências , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Feminino , Alemanha/epidemiologia , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Modelos de Riscos Proporcionais , Sistema de Registros , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Centros de Atenção Terciária/tendências , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
18.
J Hepatol ; 57(5): 995-1003, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22728872

RESUMO

BACKGROUND & AIMS: CYLD is a tumor suppressor gene that is mutated in familial cylindromatosis, an autosomal dominant predisposition to tumors of skin appendages. Reduced CYLD expression has been observed in other tumor entities, including hepatocellular carcinoma. In the present study, we analyzed the role of CYLD in liver homeostasis and hepatocarcinogenesis in vivo. METHODS: Mice with liver-specific deletion of CYLDexon7/8 (CYLD(FF)xAlbCre) were generated. Liver tissues were histologically analyzed and oval cell activation was investigated. Hepatocarcinogenesis was induced by diethylnitrosamine/phenobarbital (DEN/PB). Microarray expression profiling of livers was performed in untreated as well as DEN/PB-treated mice. NF-κB signaling was assessed by ELISA, quantitative real-time PCR, and Western blotting. RESULTS: CYLD(FF)xAlbCre hepatocytes and cholangiocytes did not express full-length CYLD (FL-CYLD) protein but showed increased expression of the naturally occurring short-CYLD splice variant (s-CYLD). CYLD(FF)xAlbCre mice exhibited a prominent biliary phenotype with ductular reaction and biliary-type fibrosis. In addition, CYLD(FF)xAlbCre mice showed a significantly increased sensitivity towards DEN/PB-induced hepatocarcinogenesis. Moreover, we could observe the development of cholangiocellular carcinoma, in line with enhanced oval cell activity. NF-κB-signaling was increased in livers of CYLD(FF)xAlbCre mice and likely contributed to the inflammatory and fibrotic response. CONCLUSIONS: The deletion of exon7/8 of the CYLD gene activates oval cells, leads to a biliary phenotype, and increases the susceptibility towards carcinogenesis in the liver. Thus, our study presents a novel model of biliary damage and liver fibrosis, followed by cancer development.


Assuntos
Doenças Biliares/genética , Cisteína Endopeptidases/genética , Cisteína Endopeptidases/metabolismo , Éxons/genética , Deleção de Genes , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/genética , Fígado/metabolismo , Animais , Doenças Biliares/patologia , Enzima Desubiquitinante CYLD , Dimetilnitrosamina/efeitos adversos , Modelos Animais de Doenças , Fibrose , Predisposição Genética para Doença/genética , Homeostase , Técnicas In Vitro , Neoplasias Hepáticas/induzido quimicamente , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Fenobarbital/efeitos adversos , Fenótipo , Fatores de Risco
19.
J Hepatol ; 55(6): 1272-80, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21703207

RESUMO

BACKGROUND & AIMS: Apoptosis is crucially involved in acute and chronic liver injury, including viral, cholestatic, toxic, and metabolic liver disease. Additionally, dysregulation of apoptosis signaling pathways has been implicated in hepatocarcinogenesis. The most prominent members of the apoptosis-mediating tumor necrosis factor receptor superfamily are the TNF-R1 (CD120a) and the CD95 (Apo-1/Fas) receptor. Although extensively studied, the intracellular signaling events in hepatocytes are only incompletely understood. METHODS: To examine the role of the caspase-8 homolog cellular FLICE-inhibitory protein (c-FLIP) in liver injury, we generated mice with hepatocyte specific deletion of c-FLIP. Three models of acute liver injury were employed: the agonistic anti-CD95 antibody Jo2, d-galactosamine and LPS (GalN/LPS), and concanavalin A. RESULTS: Conditional ablation of c-FLIP in hepatocytes augmented liver injury and cell death in all three models of liver injury. CD95- and GalN/LPS-induced liver injury was ameliorated by a pancaspase inhibitor, while ConA-induced injury was unaffected by caspase inhibition. Augmented activation of the MAPK JNK was observed in parallel to liver injury in c-FLIP knockout mice in all injury models; however, inhibition of JNK only affected TNF- and ConA-mediated injury. CONCLUSIONS: In summary, c-FLIP is a central regulator of cell death in hepatocytes, involving increased activation of caspases and the MAPK JNK.


Assuntos
Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD/deficiência , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/patologia , Hepatócitos/metabolismo , Hepatócitos/patologia , Receptores de Morte Celular/metabolismo , Animais , Antracenos/farmacologia , Apoptose , Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD/genética , Caspases/metabolismo , Concanavalina A/toxicidade , Feminino , Galactosamina/toxicidade , Hepatócitos/efeitos dos fármacos , Lipopolissacarídeos/toxicidade , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Camundongos Knockout , Receptor fas/agonistas
20.
Microcirculation ; 18(3): 205-13, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21175929

RESUMO

BACKGROUND: IRI still is a major problem in liver surgery due to warm ischemia and organ manipulation. Steatosis is not only induced by diabetes, hyperalimentation, alcohol and toxins, but also chemotherapy given before resection. Since steatotic livers are prone to Kupffer cell-dependent IRI, protection of steatotic livers is of special interest. This study was designed to compare the effect of taurine and glycine on IRI in steatotic livers. MATERIALS AND METHODS: Steatosis was induced with ethanol (7 g/kg b.w.; p.o.) in female SD rats. Ten minutes after inactivation of Kupffer cells with taurine or glycine (300 mM; i.v.), left liver lobes underwent 60 minutes of warm ischemia. Controls received the same volume of valine (300 mM; i.v.) or normal saline. After reperfusion, white blood cell-endothelial interactions and latex-bead phagocytosis by Kupffer cells were investigated. Liver enzymes were measured to estimate injury. For statistical analysis, ANOVA and Student's t-test were used. RESULTS: Glycine and taurine significantly decreased leukocyte- and platelet-endothelium interactions and latex-bead phagocytosis (p < 0.05). Liver enzymes were significantly lower after glycine and taurine (p < 0.05). CONCLUSIONS: This study shows that preconditioning with taurine or glycine is equally effective in preventing injury to fatty livers most likely via Kupffer cell-dependent mechanisms.


Assuntos
Fígado Gorduroso/tratamento farmacológico , Glicina/farmacologia , Células de Kupffer/imunologia , Traumatismo por Reperfusão/prevenção & controle , Taurina/farmacologia , Animais , Comunicação Celular/efeitos dos fármacos , Ensaios Enzimáticos Clínicos , Fígado Gorduroso/patologia , Feminino , Glicina/uso terapêutico , Células de Kupffer/efeitos dos fármacos , Microscopia , Substâncias Protetoras , Ratos , Ratos Sprague-Dawley , Taurina/uso terapêutico , Resultado do Tratamento
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