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1.
Genes Dev ; 29(6): 658-71, 2015 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-25792600

RESUMO

Pancreatic ductal adenocarcinoma (PDA) develops predominantly through pancreatic intraepithelial neoplasia (PanIN) and intraductal papillary mucinous neoplasm (IPMN) precursor lesions. Pancreatic acinar cells are reprogrammed to a "ductal-like" state during PanIN-PDA formation. Here, we demonstrate a parallel mechanism operative in mature duct cells during which functional cells undergo "ductal retrogression" to form IPMN-PDA. We further identify critical antagonistic roles for Brahma-related gene 1 (Brg1), a catalytic subunit of the SWI/SNF complexes, during IPMN-PDA development. In mature duct cells, Brg1 inhibits the dedifferentiation that precedes neoplastic transformation, thus attenuating tumor initiation. In contrast, Brg1 promotes tumorigenesis in full-blown PDA by supporting a mesenchymal-like transcriptional landscape. We further show that JQ1, a drug that is currently being tested in clinical trials for hematological malignancies, impairs PDA tumorigenesis by both mimicking some and inhibiting other Brg1-mediated functions. In summary, our study demonstrates the context-dependent roles of Brg1 and points to potential therapeutic treatment options based on epigenetic regulation in PDA.


Assuntos
Carcinoma Ductal Pancreático/fisiopatologia , Transformação Celular Neoplásica/genética , DNA Helicases/metabolismo , Proteínas Nucleares/metabolismo , Neoplasias Pancreáticas/fisiopatologia , Fatores de Transcrição/metabolismo , Animais , Azepinas/farmacologia , Azepinas/uso terapêutico , Carcinoma Ductal Pancreático/tratamento farmacológico , Transformação Celular Neoplásica/efeitos dos fármacos , DNA Helicases/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Proteínas Nucleares/genética , Neoplasias Pancreáticas/tratamento farmacológico , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Fatores de Transcrição SOX9/genética , Fatores de Transcrição SOX9/metabolismo , Fatores de Transcrição/genética , Triazóis/farmacologia , Triazóis/uso terapêutico , Células Tumorais Cultivadas
2.
Eur J Immunol ; 51(5): 1182-1194, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33521935

RESUMO

Stringent regulation of the inflammatory response is crucial for normal tissue regeneration. Here, we analyzed the role of Toll-like receptor 3 (TLR3) in pancreatic regeneration after acute pancreatitis (AP). AP was induced by caerulein treatment in mice with global TLR3 deficiency (TLR3OFF ) or in mice re-expressing TLR3 exclusively in the myeloid cell lineage (TLR3Mye ). Compared to WT mice, TLR3OFF mice had a markedly increased formation of acinar-to-ductal metaplasia (ADM) that persisted until day 7 after initiation of AP. Pancreatic tissue of WT mice was completely regenerated after 5 days with no detectable ADM structures. The enhancing effect of TLR3-deficiency on ADM formation was closely linked with an increased and prolonged accumulation of macrophages in pancreata of TLR3OFF mice. Importantly, the phenotype of TLR3OFF mice was rescued in TLR3Mye mice, demonstrating the causative role of myeloid cell selective TLR3 signaling. Moreover, in vitro stimulation of macrophages through TLR3 initiated cell death by a caspase-8-associated mechanism. Therefore, these findings provide evidence that TLR3 signaling in myeloid cells is sufficient to limit inflammation and ADM formation and to promote regeneration after AP. Notably, resolution of inflammation after AP was associated with macrophage sensitivity to TLR3-mediated cell death.


Assuntos
Expressão Gênica , Células Mieloides/metabolismo , Pancreatite/genética , Pancreatite/metabolismo , Receptor 3 Toll-Like/genética , Doença Aguda , Animais , Biomarcadores , Proliferação de Células , Citocinas/metabolismo , Modelos Animais de Doenças , Imuno-Histoquímica , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , Camundongos Knockout , Células Mieloides/imunologia , Pancreatite/imunologia , Pancreatite/patologia , Regeneração/genética , Transdução de Sinais , Receptor 3 Toll-Like/metabolismo
3.
J Hepatol ; 74(2): 380-393, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32916216

RESUMO

BACKGROUND & AIMS: Angiocrine signaling by liver sinusoidal endothelial cells (LSECs) regulates hepatic functions such as growth, metabolic maturation, and regeneration. Recently, we identified GATA4 as the master regulator of LSEC specification during development. Herein, we studied the role of endothelial GATA4 in the adult liver and in hepatic pathogenesis. METHODS: We generated adult Clec4g-icretg/0xGata4fl/fl (Gata4LSEC-KO) mice with LSEC-specific depletion of Gata4. Livers were analyzed by histology, electron microscopy, immunohistochemistry/immunofluorescence, in situ hybridization, and LSECs were isolated for gene expression profiling, ChIP- and ATAC-sequencing. Partial hepatectomy was performed to assess regeneration. We used choline-deficient, l-amino acid-defined (CDAA) diet and chronic carbon tetrachloride exposure to model liver fibrosis. Human single cell RNA-seq data sets were analyzed for endothelial alterations in healthy and cirrhotic livers. RESULTS: Genetic Gata4 deficiency in LSECs of adult mice caused perisinusoidal liver fibrosis, hepatopathy and impaired liver regeneration. Sinusoidal capillarization and LSEC-to-continuous endothelial transdifferentiation were accompanied by a profibrotic angiocrine switch involving de novo endothelial expression of hepatic stellate cell-activating cytokine PDGFB. Increased chromatin accessibility and amplification by activated MYC mediated angiocrine Pdgfb expression. As observed in Gata4LSEC-KO livers, CDAA diet-induced perisinusoidal liver fibrosis was associated with GATA4 repression, MYC activation and a profibrotic angiocrine switch in LSECs. Comparison of CDAA-fed Gata4LSEC-KO and control mice demonstrated that endothelial GATA4 indeed protects against dietary-induced perisinusoidal liver fibrosis. In human cirrhotic livers, GATA4-positive LSECs and endothelial GATA4 target genes were reduced, while non-LSEC endothelial cells and MYC target genes including PDGFB were enriched. CONCLUSIONS: Endothelial GATA4 protects against perisinusoidal liver fibrosis by repressing MYC activation and profibrotic angiocrine signaling at the chromatin level. Therapies targeting the GATA4/MYC/PDGFB/PDGFRß axis offer a promising strategy for prevention and treatment of liver fibrosis. LAY SUMMARY: The liver vasculature is supposed to play a major role in the development of liver fibrosis and cirrhosis, which can lead to liver failure and liver cancer. Herein, we discovered that structural and transcriptional changes induced by genetic deletion of the transcription factor GATA4 in the hepatic endothelium were sufficient to cause liver fibrosis. Activation of the transcription factor MYC and de novo expression of the "angiocrine" growth factor PDGFB were identified as downstream drivers of fibrosis and as potential therapeutic targets for this potentially fatal disease.


Assuntos
Células Endoteliais/metabolismo , Fator de Transcrição GATA4/metabolismo , Cirrose Hepática , Fígado , Linfocinas , Fator de Crescimento Derivado de Plaquetas , Animais , Cromatina/metabolismo , Descoberta de Drogas , Perfilação da Expressão Gênica , Células Estreladas do Fígado/metabolismo , Humanos , Fígado/irrigação sanguínea , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática/metabolismo , Cirrose Hepática/prevenção & controle , Regeneração Hepática/fisiologia , Linfocinas/genética , Linfocinas/metabolismo , Camundongos , Fator de Crescimento Derivado de Plaquetas/genética , Fator de Crescimento Derivado de Plaquetas/metabolismo , Transdução de Sinais/efeitos dos fármacos , Dedos de Zinco
4.
Am J Pathol ; 190(2): 358-371, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31783007

RESUMO

Liver sinusoidal endothelial cells (LSECs) control organ functions, metabolism, and development through the secretion of angiokines. LSECs express hepatocyte growth factor (Hgf), which is involved in prenatal development, metabolic homeostasis, and liver regeneration. This study aimed to elucidate the precise contribution of LSEC-derived Hgf in physiological homeostasis and liver regeneration. Stab2-iCretg/wt;Hgffl/fl (HgfΔLSEC) mice were generated to abrogate Hgf expression selectively in LSECs from early fetal development onwards, to study global development, metabolic and endothelial zonation, and organ functions as well as liver regeneration in response to 70% partial hepatectomy (PH). Although zonation and liver/body weight ratios were not altered, total body weight and total liver weight were reduced in HgfΔLSEC. Necrotic organ damage was more marked in HgfΔLSEC mice, and regeneration was delayed 72 hours after PH. This was associated with decreased hepatocyte proliferation at 48 hours after PH. Molecularly, HgfΔLSEC mice showed down-regulation of Hgf/c-Met signaling and decreased expression of Deptor in hepatocytes. In vitro knockdown of Deptor was associated with decreased proliferation. Therefore, angiocrine Hgf controls hepatocyte proliferation and susceptibility to necrosis after partial hepatectomy via the Hgf/c-Met axis involving Deptor to prevent excessive organ damage.


Assuntos
Tamanho Corporal , Proliferação de Células , Fator de Crescimento de Hepatócito/fisiologia , Hepatócitos/citologia , Hepatopatias/prevenção & controle , Regeneração Hepática , Organogênese/fisiologia , Animais , Moléculas de Adesão Celular Neuronais/fisiologia , Endotélio/citologia , Endotélio/metabolismo , Feminino , Hepatectomia , Hepatócitos/fisiologia , Homeostase , Hepatopatias/metabolismo , Hepatopatias/patologia , Masculino , Camundongos , Camundongos Knockout , Comunicação Parácrina , Transdução de Sinais
5.
Endoscopy ; 52(1): 45-51, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31614373

RESUMO

BACKGROUND: Cap-assisted colonoscopy is frequently used to facilitate adenoma detection during endoscopy. However, data on how cap assistance influences polyp resection are scarce. We aimed to evaluate the impact of cap assistance with the Endocuff vision device (EVD) on the resection time for colorectal polyps in patients undergoing colonoscopy. METHODS : A randomized, prospective study was performed in a university hospital in Germany. A total of 250 patients were randomly assigned 1:1 to undergo either colonoscopy with the EVD (EVD arm) or standard colonoscopy without the use of a cap (standard arm). The primary outcome was the average duration of polypectomy. Secondary outcomes included adenoma detection rate, cecal and ileal intubation times, and propofol dosage. RESULTS: The use of EVD led to a significant reduction in the median polypectomy time in the EVD vs. standard arm (54 vs. 80 seconds, respectively; P = 0.02). This effect was strongest for polyps ≥ 6 mm. Compared with the standard group, Endocuff assistance also resulted in a shorter cecal intubation time (6 vs. 8 minutes; P = 0.03) and overall colonoscopy time (23 vs. 27 minutes; P = 0.02). In contrast, no difference in withdrawal time was observed. The polyp and adenoma detection rates did not differ significantly between the two groups. CONCLUSION: Endocuff-assisted colonoscopy reduces the duration of polypectomy, which may be due to a more stable scope position during resection. Further studies are needed to investigate whether comparable effects will be seen for other interventions, such as clipping or biopsy sampling.


Assuntos
Pólipos do Colo , Colonoscopia , Ceco , Pólipos do Colo/cirurgia , Alemanha , Humanos , Íleo , Estudos Prospectivos , Padrões de Referência
6.
J Surg Res ; 255: 346-354, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32599454

RESUMO

BACKGROUND: For patients with colorectal cancer and synchronous liver metastasis, either a simultaneous, or a two-staged resection of the primary tumor and the liver metastases is possible. There are currently no guidelines preferring one approach to the other. MATERIAL AND METHODS: Consecutive patients who underwent hepatic resection at our university hospital from 2007-2016 were included. Clinical, histopathologic, serologic, and survival data were analyzed. The primary end point was tumor-specific survival for patients with simultaneous versus staged resections. RESULTS: Of all 140 patients, 68 underwent simultaneous resection and 72 underwent staged resection. The characteristics of both groups were comparable. Patients with simultaneous resections had a shorter duration of cumulative operation time (299 versus 460 min; P = 0.003) and a shorter cumulative length of hospital stay (23 versus 43 d; P = 0.002). Perioperative mortality (P = 0.257) did not differ significantly; however, patients with simultaneous resections had higher rates of grade 2 complications according to Clavien-Dindo (P < 0.001). Tumor-specific 1-y survival was 85 ± 5% for simultaneous and 83 ± 5% for staged resection (P = 0.631). On multivariable analysis, pT4 (P = 0.038), pN3 (P = 0.003), and G3/4 (P = 0.041) of the primary tumor and postoperative complications (Clavien-Dindo 3/4/5, P = 0.003) were poor prognostic factors regarding tumor-specific survival. CONCLUSIONS: This is one of the largest and most thoroughly documented retrospective single-center studies of consecutive patients with synchronous hepatic metastases. Simultaneous resection of colorectal cancer together with hepatic metastases is a safe procedure in selected patients and does not have a significant influence on long-term survival.


Assuntos
Carcinoma/cirurgia , Neoplasias Colorretais/cirurgia , Procedimentos Cirúrgicos do Sistema Digestório/estatística & dados numéricos , Neoplasias Hepáticas/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma/mortalidade , Carcinoma/secundário , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Feminino , Alemanha/epidemiologia , Humanos , Fígado/patologia , Fígado/cirurgia , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/secundário , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos , Adulto Jovem
7.
Pancreatology ; 19(4): 541-547, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31109903

RESUMO

OBJECTIVES: The importance of the Calcitonin-gene-related-peptide-pathway (CGRP) as neuronal modulator of innate immune responses in mice has been previously demonstrated. The CGRP-receptor is composed of two subunits: the receptor-activity-modifying-protein-1 (RAMP1) and the calcitonin-receptor-like-receptor (CLR). CGRP can influence immune cells and their capacity of producing inflammatory cytokines. Using a RAMP1 knockout-mouse (RAMP1-/-) we examined the role of the CGRP-receptor in the acute-phase of cerulein-induced pancreatitis. METHODS: Hourly cerulein-injections for a period of 8 h in RAMP1-/- and wild-type mice were performed. To compare severity and extent of inflammation in RAMP1-/- and wild-type mice, histological analyses were done and cytokine levels were assessed using qRT-PCR 8 h, 24 h, 2 days, and 7 days post-cerulein-treatment. Furthermore, serum activities of LDH and lipase were determined. RESULTS: After 8 h RAMP1-/- mice showed a higher pancreas-to-body-weight-ratio, increased tissue edema and immune cell infiltration with higher amount of F4/80-positive cells as compared to wild-type mice. Overall infiltration of immune cells at 24 h was increased in RAMP1-/- mice and composed predominantly of MPO-positive neutrophils. In addition, after 24 h RAMP1-/- mice presented a higher pancreas-to-body-weight-ratio, higher expression of Ccl3, Il6, and Il1b and increased number of cleaved caspase 3 positive cells. Serum lipase correlated with the extent of tissue damage in RAMP1-/- compared to wild-type mice 24 h post-cerulein treatment. CONCLUSION: Mice lacking RAMP1 showed increased inflammation, tissue edema, and pancreas injury particularly in the early phase of acute pancreatitis. This study highlights the essential role of CGRP for dampening the innate immune response in acute pancreatitis.


Assuntos
Imunidade Inata/genética , Pancreatite/genética , Pancreatite/imunologia , Proteína 1 Modificadora da Atividade de Receptores/genética , Doença Aguda , Animais , Ceruletídeo , Citocinas/sangue , Feminino , Inflamação/induzido quimicamente , Inflamação/patologia , L-Lactato Desidrogenase/metabolismo , Lipase/análise , Lipase/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Infiltração de Neutrófilos , Tamanho do Órgão , Pancreatite/induzido quimicamente , Proteína 1 Modificadora da Atividade de Receptores/imunologia
8.
Am J Pathol ; 186(11): 2934-2944, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27639167

RESUMO

Perturbation of pancreatic acinar cell state can lead to acinar-to-ductal metaplasia (ADM), a precursor lesion to the development of pancreatic ductal adenocarcinoma (PDAC). In the pancreas, Notch signaling is active both during development and in adult cellular differentiation processes. Hes1, a key downstream target of the Notch signaling pathway, is expressed in the centroacinar compartment of the adult pancreas as well as in both preneoplastic and malignant lesions. In this study, we used a murine genetic in vivo approach to ablate Hes1 in pancreatic progenitor cells (Ptf1a+/Cre; Hes1fl/fl). Using this model, we studied the role of Hes1 in both acinar cell plasticity and pancreatic regeneration after caerulein-induced pancreatitis and in KrasG12D-driven PDAC development. We show that, although pancreatic development is not perturbed on the deletion of Hes1, terminal acinar differentiation in the adult pancreas is compromised. Moreover, the loss of Hes1 leads to the impaired regeneration of the exocrine compartment, accelerated fatty metaplasia, and persistent ADM after acute caerulein-induced pancreatitis. In KrasG12D-driven carcinogenesis, Hes1 ablation resulted in increased ADM, decreased formation of high-grade pancreatic intraepithelial neoplasias, and accelerated development of PDAC with shortened survival time. In conclusion, Hes1 plays a key role in acinar cell integrity and plasticity on cellular insults. Furthermore, Hes1 is an essential component of the pancreatic intraepithelial neoplasias-to-PDAC route in KrasG12D-driven mouse pancreatic carcinogenesis.


Assuntos
Carcinoma Ductal Pancreático/etiologia , Neoplasias Pancreáticas/etiologia , Transdução de Sinais , Fatores de Transcrição HES-1/metabolismo , Células Acinares/patologia , Células Acinares/fisiologia , Animais , Carcinogênese , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , Diferenciação Celular , Plasticidade Celular , Ceruletídeo/efeitos adversos , Modelos Animais de Doenças , Feminino , Humanos , Masculino , Metaplasia , Camundongos , Pâncreas/patologia , Pâncreas/fisiologia , Pâncreas Exócrino/patologia , Pâncreas Exócrino/fisiologia , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Pancreatite/induzido quimicamente , Pancreatite/patologia , Regeneração , Células-Tronco/patologia , Células-Tronco/fisiologia , Fatores de Transcrição HES-1/genética
9.
Pancreatology ; 17(3): 350-353, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28473229

RESUMO

OBJECTIVES: Pancreatic ductal adenocarcinoma (PDAC) is thought to derive from different precursor lesions including the recently identified atypical flat lesions (AFL). While all precursor lesions and PDAC share ductal characteristics, there is an ongoing debate about the cellular origin of the different PDAC precursor lesions. In particular, pancreatic acinar cells have previously been shown to display a remarkable plasticity being able to undergo ductal dedifferentiation in the context of oncogenic stimuli. METHODS: Histological analyses were performed in a murine PDAC model that specifically expresses oncogenic Kras in adult pancreatic acinar cells. Occurrence, characterization, and lineage tracing of AFLs were investigated. RESULTS: Upon expression of oncogenic Kras in adult pancreatic acinar cells, AFLs with typical morphology and expression profile arise. Lineage tracing confirmed that the AFLs were of acinar origin. CONCLUSIONS: Using a murine PDAC model, this study identifies pancreatic acinar cells as a cellular source for AFLs.


Assuntos
Células Acinares/patologia , Carcinoma Ductal Pancreático/patologia , Neoplasias Pancreáticas/patologia , Animais , Carcinoma Ductal Pancreático/induzido quimicamente , Carcinoma Ductal Pancreático/metabolismo , Diferenciação Celular , Transformação Celular Neoplásica/patologia , Antagonistas de Estrogênios , Imuno-Histoquímica , Camundongos , Neoplasias Pancreáticas/induzido quimicamente , Neoplasias Pancreáticas/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/biossíntese , Proteínas Proto-Oncogênicas p21(ras)/genética , Tamoxifeno
10.
Future Oncol ; 11(2): 193-203, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25040106

RESUMO

BACKGROUND: N-acetyl-glucosaminidase (NAG) is a potential marker of genotoxicity. We retrospectively analyzed plasma NAG and clinico-pathologic features in advanced gastrointestinal adenocarcinoma patients. METHODS: Plasma from 118 patients and 51 healthy volunteers was analyzed for associations between NAG levels and age, disease presence, stage, treatment responses and survival. RESULTS: Pretreatment NAG correlated with age but was independently increased in metastatic versus locally advanced disease, particularly in gastric/esophageal patients. NAG was also associated with reduced overall survival. In subgroup analysis, increased NAG activity between day 1 and 2 of chemotherapy cycle 1 correlated with treatment response. CONCLUSION: We demonstrated that NAG correlates with gastrointestinal cancer outcomes. Further studies are required to determine if plasma markers of genotoxicity can be useful for disease monitoring.


Assuntos
Acetilglucosaminidase/sangue , Adenocarcinoma/sangue , Neoplasias Colorretais/sangue , Neoplasias Esofágicas/sangue , Neoplasias Gástricas/sangue , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/mortalidade , Adenocarcinoma/secundário , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/uso terapêutico , Estudos de Casos e Controles , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/mortalidade , Neoplasias Esofágicas/patologia , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologia , Resultado do Tratamento , Adulto Jovem
11.
AIDS Res Ther ; 12(1): 1, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25598834

RESUMO

BACKGROUND: While HIV, AIDS and atypical Mycobacterium infections are closely linked, the use of Integrase-Inhibitor based cART, notably raltegravir-based regimens is more widespread. RAL should be double-dosed to 800 mg semi-daily in situation of rifampicin co-medication, because RAL is more rapidly metabolized due to rifampicin-induced Uridine-5'-diphosph- gluronosyl-transferase (UGT1A1). Recently, it was speculated that chewed RAL might lead to increased absorption, which might compensate the inductive effect of rifampicin-rapid metabolized RAL, as part of cost-saving effects in countries with high-tuberculosis prevalence and less economic power. METHODS: We report measurement of raltegravir pharmacokinetics in a 34-year AIDS-patient suffering from disseminated Mycobacterium avium infection with necessity of parenteral rifampicin treatment. RAL levels were measured with HPLC (internal standard: carbamazepine, LLQ 11 ng/ml, validation with Valistat 2.0 program (Arvecon, Germany)). For statistical analysis, a two-sided Wilcoxon signed rank test for paired samples was used. RESULTS: High intra-personal variability in raltegravir serum levels was seen. Comparable Cmax concentrations were found for 800 mg chewed and swallowed RAL, as well as for 400 mg chewed and swallowed RAL. While Cmax seems to be more dependent from overall RAL dosing than from swallowed or chewed tablets, increased AUC12 is clearly linked to higher RAL dosages per administration. Anyway, chewed raltegravir showed a rapid decrease in serum levels. CONCLUSIONS: We found no evidence that chewed 400 mg semi-daily raltegravir in rifampicin co-medication leads to optimized pharmacokinetics. There is need for more data from randomized trials for further recommendations.

12.
Gut ; 63(4): 656-64, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23645620

RESUMO

OBJECTIVES: Emerging evidence from mouse models suggests that mutant Kras can drive the development of pancreatic ductal adenocarcinoma (PDA) precursors from acinar cells by enforcing ductal de-differentiation at the expense of acinar identity. Recently, human genome-wide association studies have identified NR5A2, a key regulator of acinar function, as a susceptibility locus for human PDA. We investigated the role of Nr5a2 in exocrine maintenance, regeneration and Kras driven neoplasia. DESIGN: To investigate the function of Nr5a2 in the pancreas, we generated mice with conditional pancreatic Nr5a2 deletion (PdxCre(late); Nr5a2(c/c)). Using this model, we evaluated acinar differentiation, regeneration after caerulein pancreatitis and Kras driven pancreatic neoplasia in the setting of Nr5a2 deletion. RESULTS: We show that Nr5a2 is not required for the development of the pancreatic acinar lineage but is important for maintenance of acinar identity. Nr5a2 deletion leads to destabilisation of the mature acinar differentiation state, acinar to ductal metaplasia and loss of regenerative capacity following acute caerulein pancreatitis. Loss of Nr5a2 also dramatically accelerates the development of oncogenic Kras driven acinar to ductal metaplasia and PDA precursor lesions. CONCLUSIONS: Nr5a2 is a key regulator of acinar plasticity. It is required for maintenance of acinar identity and re-establishing acinar fate during regeneration. Nr5a2 also constrains pancreatic neoplasia driven by oncogenic Kras, providing functional evidence supporting a potential role as a susceptibility gene for human PDA.


Assuntos
Carcinoma de Células Acinares/fisiopatologia , Carcinoma Ductal Pancreático/fisiopatologia , Neoplasias Pancreáticas/fisiopatologia , Proteínas Proto-Oncogênicas p21(ras)/fisiologia , Receptores Citoplasmáticos e Nucleares/fisiologia , Animais , Diferenciação Celular/fisiologia , Linhagem Celular , Transformação Celular Neoplásica , Ceruletídeo/farmacologia , Camundongos , Pancreatite/induzido quimicamente , Pancreatite/fisiopatologia , Reação em Cadeia da Polimerase em Tempo Real
13.
Endosc Int Open ; 12(3): E361-E366, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38464982

RESUMO

Background and study aims The prognosis for pancreatic cancer remains poor. Molecular diagnostics and customized therapies are becoming increasingly important in clinical routine. Patient-derived, predictive model systems such as organoids have the potential to substantially increase the depth of information from biopsy material by functional and molecular characterization. We compared the extent to which the use of fine-needle aspiration needles (FNA, 22G) or fine-needle biopsy needles (FNB, 22G) influences the generation of pancreatic cancer patient-derived organoids (PDOs) to establish endoscopic standards of organoid technology. Patients and methods Endoscopic ultrasound (EUS)-guided punctures by EUS-FNA and EUS-FNB of pancreatic masses highly suspicious for adenocarcinoma (detected by computed tomography and/or magnetic resonance imaging) were prospectively evaluated. Consecutive patients received EUS-FNA and EUS-FNB in a randomized order without the need to exchange the needle shaft (only the inner needle type (FNA/-B) was exchanged) between the passes. With each needle type, the specimens for histological analysis and for PDOs were obtained separately. Results Fifty patients were enrolled in the study. Histology revealed malignancy in 42 of 50 cases (84%). In total PDOs were generated from 17 patients (34%). Of these, nine were established by FNB only, two by FNA only, and six by both FNA and FNB. Histology revealed malignancy in 13 of 17 PDO cases (76%). In two histologically false-negative cases, PDOs could be established. Conclusions EUS-FNB was superior to EUS-FNA in terms of successful generation of PDOs, although it failed to show statistical significance.

14.
PLoS One ; 18(11): e0294257, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38033027

RESUMO

INTRODUCTION: Hepatic fibrosis is a progressive pathological process involving the exhaustion of hepatocellular regenerative capacity and ultimately leading to the development of cirrhosis and even hepatocellular carcinoma. Brg1, the core subunit of the SWI/SNF chromatin-remodeling complex, was recently identified as important for liver regeneration. This study investigates the role of Brg1 in hepatic fibrosis development. METHODS: Hepatocyte-specific Brg1 knockout mice were generated and injected with carbon tetrachloride (CCl4) for 4, 6, 8, and 12 weeks to induce liver fibrosis. Afterwards, liver fibrosis and liver damage were assessed. RESULTS: Brg1 expression was significantly increased in the fibrotic liver tissue of wild-type mice, as compared to that of untreated wild-type mice. The livers of the Brg1 knockout animals showed reduced liver inflammation, extracellular matrix accumulation, and liver fibrosis. TNF-α and NF-κB-mediated inflammatory response was reduced in Brg1 knockout animals. CONCLUSION: Brg1 promotes the progression of liver fibrosis in mice and may therefore be used as a potential therapeutic target for treating patients with liver fibrosis due to chronic injury.


Assuntos
Carcinoma Hepatocelular , Hepatite , Neoplasias Hepáticas , Animais , Camundongos , Tetracloreto de Carbono/toxicidade , Carcinoma Hepatocelular/patologia , Matriz Extracelular/metabolismo , Fibrose , Hepatite/patologia , Inflamação/patologia , Fígado/metabolismo , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/genética , Cirrose Hepática/metabolismo , Neoplasias Hepáticas/patologia , Camundongos Knockout
15.
Hepatology ; 53(5): 1608-17, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21520174

RESUMO

UNLABELLED: Telomere shortening impairs liver regeneration in mice and is associated with cirrhosis formation in humans with chronic liver disease. In humans, telomerase mutations have been associated with familial diseases leading to bone marrow failure or lung fibrosis. It is currently unknown whether telomerase mutations associate with cirrhosis induced by chronic liver disease. The telomerase RNA component (TERC) and the telomerase reverse transcriptase (TERT) were sequenced in 1,121 individuals (521 patients with cirrhosis induced by chronic liver disease and 600 noncirrhosis controls). Telomere length was analyzed in patients carrying telomerase gene mutations. Functional defects of telomerase gene mutations were investigated in primary human fibroblasts and patient-derived lymphocytes. An increased incidence of telomerase mutations was detected in cirrhosis patients (allele frequency 0.017) compared to noncirrhosis controls (0.003, P value 0.0007; relative risk [RR] 1.859; 95% confidence interval [CI] 1.552-2.227). Cirrhosis patients with TERT mutations showed shortened telomeres in white blood cells compared to control patients. Cirrhosis-associated telomerase mutations led to reduced telomerase activity and defects in maintaining telomere length and the replicative potential of primary cells in culture. CONCLUSION: This study provides the first experimental evidence that telomerase gene mutations are present in patients developing cirrhosis as a consequence of chronic liver disease. These data support the concept that telomere shortening can represent a causal factor impairing liver regeneration and accelerating cirrhosis formation in response to chronic liver disease.


Assuntos
Cirrose Hepática/genética , Mutação , Telomerase/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença Crônica , Feminino , Humanos , Cirrose Hepática/etiologia , Hepatopatias/complicações , Masculino , Pessoa de Meia-Idade
16.
Dig Dis Sci ; 57(11): 2988-94, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22674401

RESUMO

BACKGROUND: Homozygous C282Y mutation in HFE gene is responsible for the majority of hereditary hemochromatosis cases. Since 1996 this mutation can be identified by a simple genetic test. AIMS: To determine the clinical presentations in patients with homozygous HFE C282Y mutation and the impact of genetic testing on the time needed for diagnosis. METHODS: A total of 414 patients diagnosed with C282Y homozygous hereditary hemochromatosis before and after the introduction of genetic testing were evaluated regarding symptoms and clinical findings at diagnosis as well as first hemochromatosis-related clinical features in their past medical history. RESULTS: At the time of diagnosis, the predominant symptom was joint pain, in particular of the hands/wrists. Those patients presenting with hand/wrist arthralgia had significantly higher ferritin levels than patients without this joint involvement (p = 0.0005 for males and p < 0.0001 for females). After the introduction of the HFE genetic test an earlier diagnosis after first onset of hemochromatosis-associated clinical features was observed between 2006 and 2009 vs. 2000-2005 p = 0.01). CONCLUSIONS: Arthralgia, in particular of the hands/wrists, is a hallmark of hereditary hemochromatosis and its presence is associated with higher ferritin levels. Despite the availability of a genetic test, it often takes more than 6 years from the first onset of clinical features to diagnose hereditary hemochromatosis. This underlines the importance of raising the awareness of hemochromatosis and its typical clinical presentations.


Assuntos
Testes Genéticos/métodos , Hemocromatose/diagnóstico , Hemocromatose/genética , Antígenos de Histocompatibilidade Classe I/genética , Adulto , Comorbidade , Feminino , Homozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Estudos Retrospectivos , Estatísticas não Paramétricas , Fatores de Tempo
17.
Dig Dis Sci ; 56(2): 596-601, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21221795

RESUMO

BACKGROUND AND AIMS: Tissue specimen collection represents a cornerstone in diagnosis of proximal biliary tract malignancies offering great specificity, but only limited sensitivity. To improve the tumor detection rate, we developed a new method of forceps biopsy and compared it prospectively with endoscopic transpapillary brush cytology. PATIENTS AND METHODS: 43 patients with proximal biliary stenoses, which were suspect for malignancy, undergoing endoscopic retrograde cholangiography were prospectively recruited and subjected to both biopsy [using a double-balloon enteroscopy (DBE) forceps under a guidance of a pusher and guiding catheter with guidewire] and transpapillary brush cytology. The cytological/histological findings were compared with the final clinical diagnosis. RESULTS: 35 out of 43 patients had a malignant disease (33 cholangiocarcinomas, 1 hepatocellular carcinoma, 1 gallbladder carcinoma). The sensitivity of cytology and biopsy in these patients was 49 and 69%, respectively. The method with DBE forceps allowed a pinpoint biopsy of the biliary stenoses. Both methods had 100% specificity, and, when combined, 80% of malignant processes were detected. All patients with non-malignant conditions were correctly assigned by both methods. No clinically relevant complications were observed. CONCLUSIONS: The combination of forceps biopsy and transpapillary brush cytology is safe and offers superior detection rates compared to both methods alone, and therefore represents a promising approach in evaluation of proximal biliary tract processes.


Assuntos
Neoplasias dos Ductos Biliares/diagnóstico , Biópsia/métodos , Carcinoma Hepatocelular/diagnóstico , Colangiocarcinoma/diagnóstico , Neoplasias Hepáticas/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias dos Ductos Biliares/patologia , Ductos Biliares Intra-Hepáticos/patologia , Colangiopancreatografia Retrógrada Endoscópica , Vesícula Biliar/patologia , Humanos , Fígado/patologia , Pessoa de Meia-Idade , Instrumentos Cirúrgicos , Adulto Jovem
18.
Dtsch Med Wochenschr ; 146(4): 246-252, 2021 02.
Artigo em Alemão | MEDLINE | ID: mdl-33592660

RESUMO

Ductal pancreatic carcinoma is expected to become one of the most common malignant diseases worldwide in the coming decades. However, the prognosis of the disease remains very poor and has improved only slightly over the last decade. The 5-year survival rate of all patients with ductal adenocarcinoma has been increased to approximately 10 percent. The reasons for the very poor prognosis are the advanced stage of the disease at diagnosis with metastases already present in many cases, the anatomical location of the pancreas and the tumor biology. Therapeutically, chemotherapy remains the basis of systemic therapy. Intensive combinations with FOLFIRINOX (oxaliplatin, irinotecan, leucovorin/5-FU) and nanoparticel albumin bound (nab)paclitaxel/gemcitabine lead to an improvement in overall survival in the palliative situation; used preoperatively, they can increase the rate of secondary resections. Targeted therapies and immune checkpoint inhibitors could not be established. In patients with a proven germline mutation in the BRCA gene, a therapy with the PARP inhibitor olaparib is in the approval process.This article provides an overview of differential diagnoses, meaningful diagnostics, therapeutic concepts to improve surgical treatment, possibilities of palliative chemotherapy and targeted therapy in the presence of a BRCA mutation.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Antineoplásicos/administração & dosagem , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Ductal Pancreático/diagnóstico , Carcinoma Ductal Pancreático/terapia , Fluoruracila/administração & dosagem , Fluoruracila/uso terapêutico , Humanos , Irinotecano/administração & dosagem , Irinotecano/uso terapêutico , Leucovorina/administração & dosagem , Leucovorina/uso terapêutico , Oxaliplatina/administração & dosagem , Oxaliplatina/uso terapêutico , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/terapia
19.
Data Brief ; 31: 105973, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32671166

RESUMO

Between 2007 and 2016, 140 consecutive patients who underwent resection of colorectal cancer with simultaneous liver metastases at a single university hospital were retrospectively analysed. In order to gather information regarding potential survival differences for n = 68 simultaneous versus n = 72 staged resections of the colorectal primary tumor and the liver metastases, Clinical, histopathological, serological, and survival data were compared for those two patient groups. The rate of simultaneous tumor resections increased from approximately 25% in 2007 to >75% in 2016. There was no difference in tumor specific survival for patients with simultaneous vs. staged resection (p = 0.631). This effect continued after excluding patients with extrahepatic metastases (p = 0.440). Further, neoadjuvant treatment did not lead to differences in the tumor-specific survival (p = 0.123). Factors associated with an increased tumor-specific survival were low ASA score (p < 0.001), low number of tumor-affected lymph nodes (p < 0.001), histological grading G1/2 (p = 0.001), and a low number of liver metastases (p = 0.044). There was no significant survival difference for the primary tumor stage (pT), the Clavien-Dindo complication rate, the resection status (R0), and minor versus major hepatectomies.

20.
Sci Rep ; 10(1): 9654, 2020 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-32541781

RESUMO

Several studies have shown that over 70 different microRNAs are aberrantly expressed in pancreatic ductal adenocarcinoma (PDAC), affecting proliferation, apoptosis, metabolism, EMT and metastasis. The most important genetic alterations driving PDAC are a constitutive active mutation of the oncogene Kras and loss of function of the tumour suppressor Tp53 gene. Since the MicroRNA 34a (Mir34a) is a direct target of Tp53 it may critically contribute to the suppression of PDAC. Mir34a is epigenetically silenced in numerous cancers, including PDAC, where Mir34a down-regulation has been associated with poor patient prognosis. To determine whether Mir34a represents a suppressor of PDAC formation we generated an in vivo PDAC-mouse model harbouring pancreas-specific loss of Mir34a (KrasG12D; Mir34aΔ/Δ). Histological analysis of KrasG12D; Mir34aΔ/Δ mice revealed an accelerated formation of pre-neoplastic lesions and a faster PDAC development, compared to KrasG12D controls. Here we show that the accelerated phenotype is driven by an early up-regulation of the pro-inflammatory cytokines TNFA and IL6 in normal acinar cells and accompanied by the recruitment of immune cells. Our results imply that Mir34a restrains PDAC development by modulating the immune microenvironment of PDAC, thus defining Mir34a restauration as a potential therapeutic strategy for inhibition of PDAC development.


Assuntos
Carcinoma Ductal Pancreático/patologia , Regulação para Baixo , MicroRNAs/genética , Neoplasias Pancreáticas/patologia , Animais , Carcinoma Ductal Pancreático/genética , Regulação Neoplásica da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Interleucina-6/metabolismo , Camundongos , Neoplasias Pancreáticas/genética , Fenótipo , Proteínas Proto-Oncogênicas p21(ras)/genética , Análise de Sequência de RNA , Fator de Necrose Tumoral alfa/metabolismo
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