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1.
PLoS One ; 14(10): e0218642, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31577805

RESUMO

PURPOSE: Development of a supervised machine-learning model capable of predicting clinically relevant molecular subtypes of pancreatic ductal adenocarcinoma (PDAC) from diffusion-weighted-imaging-derived radiomic features. METHODS: The retrospective observational study assessed 55 surgical PDAC patients. Molecular subtypes were defined by immunohistochemical staining of KRT81. Tumors were manually segmented and 1606 radiomic features were extracted with PyRadiomics. A gradient-boosted-tree algorithm was trained on 70% of the patients (N = 28) and tested on 30% (N = 17) to predict KRT81+ vs. KRT81- tumor subtypes. A gradient-boosted survival regression model was fit to the disease-free and overall survival data. Chemotherapy response and survival were assessed stratified by subtype and radiomic signature. Radiomic feature importance was ranked. RESULTS: The mean±STDEV sensitivity, specificity and ROC-AUC were 0.90±0.07, 0.92±0.11, and 0.93±0.07, respectively. The mean±STDEV concordance indices between the disease-free and overall survival predicted by the model based on the radiomic parameters and actual patient survival were 0.76±0.05 and 0.71±0.06, respectively. Patients with a KRT81+ subtype experienced significantly diminished median overall survival compared to KRT81- patients (7.0 vs. 22.6 months, HR 4.03, log-rank-test P = <0.001) and a significantly improved response to gemcitabine-based chemotherapy over FOLFIRINOX (10.14 vs. 3.8 months median overall survival, HR 2.33, P = 0.037) compared to KRT81- patients, who responded significantly better to FOLFIRINOX over gemcitabine-based treatment (30.8 vs. 13.4 months median overall survival, HR 2.41, P = 0.027). Entropy was ranked as the most important radiomic feature. CONCLUSIONS: The machine-learning based analysis of radiomic features enables the prediction of subtypes of PDAC, which are highly relevant for disease-free and overall patient survival and response to chemotherapy.

2.
Eur Radiol Exp ; 3(1): 41, 2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31624935

RESUMO

BACKGROUND: To develop a supervised machine learning (ML) algorithm predicting above- versus below-median overall survival (OS) from diffusion-weighted imaging-derived radiomic features in patients with pancreatic ductal adenocarcinoma (PDAC). METHODS: One hundred two patients with histopathologically proven PDAC were retrospectively assessed as training cohort, and 30 prospectively accrued and retrospectively enrolled patients served as independent validation cohort (IVC). Tumors were segmented on preoperative apparent diffusion coefficient (ADC) maps, and radiomic features were extracted. A random forest ML algorithm was fit to the training cohort and tested in the IVC. Histopathological subtype of tumor samples was assessed by immunohistochemistry in 21 IVC patients. Individual radiomic feature importance was evaluated by assessment of tree node Gini impurity decrease and recursive feature elimination. Fisher's exact test, 95% confidence intervals (CI), and receiver operating characteristic area under the curve (ROC-AUC) were used. RESULTS: The ML algorithm achieved 87% sensitivity (95% IC 67.3-92.7), 80% specificity (95% CI 74.0-86.7), and ROC-AUC 90% for the prediction of above- versus below-median OS in the IVC. Heterogeneity-related features were highly ranked by the model. Of the 21 patients with determined histopathological subtype, 8/9 patients predicted to experience below-median OS exhibited the quasi-mesenchymal subtype, whilst 11/12 patients predicted to experience above-median OS exhibited a non-quasi-mesenchymal subtype (p < 0.001). CONCLUSION: ML application to ADC radiomics allowed OS prediction with a high diagnostic accuracy in an IVC. The high overlap of clinically relevant histopathological subtypes with model predictions underlines the potential of quantitative imaging in PDAC pre-operative subtyping and prognosis.

3.
4.
EBioMedicine ; 46: 431-443, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31401195

RESUMO

BACKGROUND: Pain due to pancreatic cancer/PCa or chronic pancreatitis/CP, is notoriously resistant to the strongest pain medications. Here, we aimed at deciphering the specific molecular mediators of pain at surgical-stage pancreatic disease and to discover novel translational targets. METHODS: We performed a systematic, quantitative analysis of the neurotransmitter/neuroenzmye profile within intrapancreatic nerves of CP and PCa patients. Ex vivo neuronal cultures treated with human pancreatic extracts, conditional genetically engineered knockout mouse models of PCa and CP, and the cerulein-induced CP model were employed to explore the therapeutic potential of the identified targets. FINDINGS: We identified a unique enrichment of neuronal nitric-oxide-synthase (nNOS) in the pancreatic nerves of CP patients with increasing pain severity. Employment of ex vivo neuronal cultures treated with pancreatic tissue extracts of CP patients, and brain-derived-neurotrophic-factor-deficient (BDNF+/-) mice revealed neuronal enrichment of nNOS to be a consequence of BDNF loss in the progressively destroyed pancreatic tissue. Mechanistically, nNOS upregulation in sensory neurons was induced by tryptase secreted from perineural mast cells. In a head-to-head comparison of several genetically induced, painless mouse models of PCa (KPC, KC mice) or CP (Ptf1a-Cre;Atg5fl/fl) against the hypersecretion/cerulein-induced, painful CP mouse model, we show that a similar nNOS enrichment is present in the painful cerulein-CP model, but absent in painless genetic models. Consequently, mice afflicted with painful cerulein-induced CP could be significantly relieved upon treatment with the specific nNOS inhibitor NPLA. INTERPRETATION: We propose nNOS inhibition as a novel strategy to treat the unbearable pain in CP. FUND: Deutsche Forschungsgemeinschaft/DFG (DE2428/3-1 and 3-2).

5.
J Gastroenterol ; 2019 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-31456099

RESUMO

BACKGROUND: The EGFR ligand betacellulin (BTC) has been previously shown to protect mice against experimentally induced acute pancreatitis (AP). BTC binds both autonomous ERBB receptors EGFR and ERBB4. In this study, we evaluated the mechanism underlying the protection from AP-associated inflammation in detail. METHODS: AP was induced with cerulein or L-arginine and investigated in a pancreas-specific ERBB4 knockout and in an EGFR knockdown mouse model (EgfrWa5/+). Pancreatitis was evaluated by scoring inflammation, necrosis, and edema, while microarrays were performed to analyze alterations in the transcriptome between mice with AP and animals which were protected against AP. The intracellular domain (ICD) of ERBB4 was analyzed in different cell compartments. RESULTS: While the pancreas of BTC transgenic mice in the background of EgfrWa5/+ is still protected against AP, the BTC-mediated protection is no longer present in the absence of ERBB4. We further demonstrate that BTC activates the ICD of ERBB4, and increases the expression of the extracellular matrix (ECM) proteins periostin and matrix gla protein as well as the ECM modulators matrix metalloproteinases 2 and 3, but only in the presence of ERBB4. Notably, the increased expression of these proteins is not accompanied by an increased ECM amount. CONCLUSIONS: These findings suggest that BTC derivates, as a drug, or the ERBB4 receptor, as a druggable target protein, could play an important role in modulating the course of AP and even prevent AP in humans.

6.
N Engl J Med ; 381(4): 317-327, 2019 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-31157963

RESUMO

BACKGROUND: Patients with a germline BRCA1 or BRCA2 mutation make up a small subgroup of those with metastatic pancreatic cancer. The poly(adenosine diphosphate-ribose) polymerase (PARP) inhibitor olaparib has had antitumor activity in this population. METHODS: We conducted a randomized, double-blind, placebo-controlled, phase 3 trial to evaluate the efficacy of olaparib as maintenance therapy in patients who had a germline BRCA1 or BRCA2 mutation and metastatic pancreatic cancer and disease that had not progressed during first-line platinum-based chemotherapy. Patients were randomly assigned, in a 3:2 ratio, to receive maintenance olaparib tablets (300 mg twice daily) or placebo. The primary end point was progression-free survival, which was assessed by blinded independent central review. RESULTS: Of the 3315 patients who underwent screening, 154 underwent randomization and were assigned to a trial intervention (92 to receive olaparib and 62 to receive placebo). The median progression-free survival was significantly longer in the olaparib group than in the placebo group (7.4 months vs. 3.8 months; hazard ratio for disease progression or death, 0.53; 95% confidence interval [CI], 0.35 to 0.82; P = 0.004). An interim analysis of overall survival, at a data maturity of 46%, showed no difference between the olaparib and placebo groups (median, 18.9 months vs. 18.1 months; hazard ratio for death, 0.91; 95% CI, 0.56 to 1.46; P = 0.68). There was no significant between-group difference in health-related quality of life, as indicated by the overall change from baseline in the global quality-of-life score (on a 100-point scale, with higher scores indicating better quality of life) based on the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (between-group difference, -2.47 points; 95% CI, -7.27 to 2.33). The incidence of grade 3 or higher adverse events was 40% in the olaparib group and 23% in the placebo group (between-group difference, 16 percentage points; 95% CI, -0.02 to 31); 5% and 2% of the patients, respectively, discontinued the trial intervention because of an adverse event. CONCLUSIONS: Among patients with a germline BRCA mutation and metastatic pancreatic cancer, progression-free survival was longer with maintenance olaparib than with placebo. (Funded by AstraZeneca and others; POLO ClinicalTrials.gov number, NCT02184195.).


Assuntos
Adenocarcinoma/tratamento farmacológico , Antineoplásicos/uso terapêutico , Genes BRCA1 , Genes BRCA2 , Mutação em Linhagem Germinativa , Quimioterapia de Manutenção , Neoplasias Pancreáticas/tratamento farmacológico , Ftalazinas/uso terapêutico , Piperazinas/uso terapêutico , Adenocarcinoma/genética , Adenocarcinoma/mortalidade , Adenocarcinoma/secundário , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/efeitos adversos , Método Duplo-Cego , Feminino , Humanos , Estimativa de Kaplan-Meier , Quimioterapia de Manutenção/efeitos adversos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica/tratamento farmacológico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/patologia , Ftalazinas/efeitos adversos , Piperazinas/efeitos adversos , Intervalo Livre de Progressão
7.
Artigo em Inglês | MEDLINE | ID: mdl-31157455

RESUMO

BACKGROUND AND AIM: In contrast to the first peak of multi-organ failure in acute pancreatitis, the second peak is mostly triggered by septic complications. Our aim was to analyze the spectrum of pathogens and antimicrobial resistance development in relation to the time-course of the disease and its clinical outcome. METHODS: One hundred twenty-two patients with acute necrotizing pancreatitis undergoing pancreas puncture at two tertiary academic medical centers in Germany were retrospectively analyzed. RESULTS: At species level, there was a change in spectrum from Enterococcus faecalis (∆d150 - d1 = 14.6% - 16.7% = -2.1%) to Enterococcus faecium (∆d150 - d1 = 93.1% - 16.3% = 76.8%) (P < 0.001) and from Candida albicans (∆d150 - d1 = 39.7% - 23.6% = 16.1%) to non-albicans Candida spp. (∆d150 - d1 = 43.5% - 6.4% = 37.1%) (P = 0.005). Time-to-event analysis of acquired antimicrobial resistance showed that the overall number of patients with Enterobacteriaceae presented an antimicrobial susceptibility decrease by 59.7% (∆d1 - d100 = 87.0% - 27.3% = 59.7%). The cumulative incidence of multi-resistant bacteria increased with length of hospital stay (∆d150 - d1 = 49.1% - 3.1% = 46.0%) (P = 0.004). Multivariable logistic regression analysis in relation to the pathogen spectrum and antimicrobial resistance development showed a significantly higher mortality for non-albicans Candida spp. (P = 0.039, odds ratio [OR] = 3.32 [95% confidence interval [CI]: 1.07-10.35]), E. faecium (P = 0.009, OR = 3.73 [95% CI: 1.38-10.05]), and multi-resistant bacteria (P = 0.007, OR = 5.08 [95% CI: 1.55-16.66]). CONCLUSIONS: Antimicrobial treatment of infected pancreatic necrosis becomes more challenging over time, owing to a change in spectrum favoring difficult-to-treat pathogens and an increase in multi-resistant bacteria associated with worse clinical outcomes (World Health Organization trial registration number: DRKS00014785).

8.
Theranostics ; 9(5): 1280-1287, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30867830

RESUMO

The most frequent malignancy of the pancreas is the pancreatic ductal adenocarcinoma (PDAC). Despite many efforts PDAC has still a dismal prognosis. Biomarkers for early disease stage diagnosis as a prerequisite for a potentially curative treatment are still missing. Novel blood-based markers may help to overcome this limitation. Methods: Prior to surgery plasma levels of thrombospondin-2 (THBS2), which was recently published as a novel biomarker, and CA19-9 from 52 patients with histologically proven PDAC were determined, circulating cell-free (cfDNA) was quantified. 15 patients with side-branch IPMNs without worrisome features and 32 patients with chronic pancreatitis served for comparison. Logit (logistic regression) models were used to test the performance of single biomarkers and biomarker combinations. Results: CA19-9 and THBS2 alone showed comparable c-statistics of 0.80 and 0.73, respectively, improving to 0.87 when combining these two markers. The c-statistic was further increased to 0.94 when combining CA19-9 and THBS2 with cfDNA quantification. This marker combination performed best for all PDAC stages but also for PDACs grouped by stage. The greatest improvement over CA19-9 was seen in the group of stage I PDAC, from 0.69 to 0.90 for the three marker combination. Conclusion:These data establish the combination of CA19-9, THBS2 and cfDNA as a composite liquid biomarker for non-invasive diagnosis of early-stage PDAC.

9.
Internist (Berl) ; 60(3): 226-234, 2019 03.
Artigo em Alemão | MEDLINE | ID: mdl-30805662

RESUMO

Acute pancreatitis (AP) has an annual incidence of 30-45 per 100,000 inhabitants. In Germany approximately one third of the cases are of biliary or alcoholic origin. The diagnosis is based on the typical epigastric pain with radiation and a threefold increase of lipase or amylase in serum. Imaging procedures only rarely need to be included for the primary diagnostics. An early risk assessment is important to be able to allocate patients with severe AP to surveillance in an intensive care unit (ICU). Elevation of blood urea nitrogen, hematocrit and blood glucose are early predictors of poor outcome.The removal of impacted gall-stones by endoscopic retrograde cholangiography (ERC) is the only causal treatment of biliary AP, which must be carried out when there are signs of cholangitis and in severe biliary AP. Pain management and early fluid substitution are the most important symptomatic approaches. In the early phase of AP 150-250 ml/h of crystalloid solution should be administered to compensate for the extravasal loss of fluid. In certain cases, the initial fluid requirement might be even higher. In the ICU setting echocardiography and advanced hemodynamic monitoring are available for guidance. Prophylactic antibiotic treatment is not recommended in mild AP and it is a matter of debate even in severe AP. Early enteral nutrition has been shown to improve the outcome. Even in cases of fluid collection and necrosis a primary surgery approach should be avoided in favor of a "step-up" procedure with radiologically guided drainage as well as endoscopic and if necessary video-assisted percutaneous retroperitoneal débridement. Surgery remains an option for complications and for infected necrosis which cannot be reached by any other means.


Assuntos
Desbridamento , Drenagem , Pancreatite Necrosante Aguda/diagnóstico , Pancreatite Necrosante Aguda/cirurgia , Colangiografia , Terapia Combinada/métodos , Alemanha , Humanos , Pancreatite Necrosante Aguda/diagnóstico por imagem
10.
Medicine (Baltimore) ; 98(4): e13044, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30681551

RESUMO

BACKGROUND: Acute pancreatitis (AP) usually has a mild course with a mortality rate below 1%. However, around 10% of patients develop severe AP (SAP) involving extra-pancreatic tissues and other organ systems. The mortality of SAP is around 42%. The outcome of SAP is closely related to the development of systemic inflammation and consecutive organ failures. Most current therapies including fluid resuscitation, antimicrobial therapy, drainage procedures, and endoscopic management of complications are symptomatic rather than causative approaches, except sphincterotomy for gallstone pancreatitis. Regarding the high mortality of SAP and its close association with systemic inflammation, extracorporeal removal of inflammatory mediators is an appealing approach. Several recent studies have demonstrated that the CytoSorb adsorber effectively eliminates inflammatory cytokines, such as IL-1ß, IL-6, IL-8, IL-10, and TNF-alpha. Some of these trials suggested that therapy with CytoSorb might improve outcome, including a reduction in the vasopressor dosage and reversal of shock.Therefore, it is the objective of this study to evaluate the effectiveness of 2 consecutive 24 h-treatments with CytoSorb on hemodynamics in patients with early SAP. METHODS: This study includes patients with early SAP (APACHE-II ≥10) and transpulmonary thermodilution hemodynamic monitoring (PiCCO; EV-1000) within a maximum of seven days from the onset of pain. Eligible patients will be treated with 2 consecutive periods of CytoSorb. A 20%-improvement in the vasopressor dependency index (VDI) - which relates is derived from mean arterial pressure (MAP) and catecholamine dosage - is the primary outcome. In addition to this clinical outcome, there are several laboratory (cytokine levels) and translational endpoints (including multiplex-ELISAs of numerous anti- and pro-inflammatory cytokines/chemokines and DNA analyses). Primary outcome analysis will compare the incidence of the primary endpoint in 30 patients from the intervention group to 60 matched controls with advanced hemodynamic monitoring recruited from recent studies in SAP within the same setting and the same centers. DISCUSSION: A potential improvement in hemodynamics and/or other outcomes by CytoSorb would provide a new therapeutic option in the early treatment of SAP with a pathophysiological rationale. TRIAL REGISTRATION: This study was registered on March 17, 2017 (ClinicalTrials.gov Identifier: NCT03082469). URL: https://clinicaltrials.gov/ct2/show/NCT03082469. VERSION: V_PACIFIC_1.0 September 30, 2018.


Assuntos
Citocinas/isolamento & purificação , Circulação Extracorpórea/métodos , Mediadores da Inflamação/isolamento & purificação , Pancreatite/terapia , APACHE , Doença Aguda , Pressão Arterial , Catecolaminas/administração & dosagem , Feminino , Hemodinâmica , Humanos , Testes de Função Renal , Masculino , Pancreatite/imunologia , Pancreatite/mortalidade , Estudos Prospectivos , Projetos de Pesquisa , Testes de Função Respiratória
11.
J Pathol ; 248(1): 6-8, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30570131

RESUMO

Obesity and acute pancreatitis are both proinflammatory conditions. Importantly, obesity increases severity in acute pancreatitis by enhancing inflammation. In a recent issue of The Journal of Pathology, Pérez and Ruiz-Pérez et al connected obesity and pancreatitis for the first time, through the transcriptional regulator PPARγ coactivator 1α (PGC-1α). Obesity reduces pancreatic PGC-1α levels and potentiates not only oxidative but also IL-6-mediated inflammatory damage during acute pancreatitis by relieving the binding of PGC-1α to the NF-κB subunit p65. Blockade of the IL-6 receptor subunit gp130 ameliorated tissue injury, substantiating the importance of deregulated PGC-1α/p65/IL-6 signaling in obesity and acute pancreatitis. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Assuntos
Pancreatite , Vinho , Carcinogênese , Humanos , NF-kappa B , Obesidade , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Reino Unido
12.
BMC Cancer ; 18(1): 1298, 2018 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-30594153

RESUMO

BACKGROUND: Even clearly resectable pancreatic cancer still has an unfavorable prognosis. Neoadjuvant or perioperative therapies might improve the prognosis of these patients. Thus, evaluation of perioperative chemotherapy in resectable pancreatic cancer in a prospective, randomized trial is warranted. A substantial improvement in overall survival of patients with metastatic pancreatic cancer with FOLFIRINOX and nab-paclitaxel/gemcitabine vs standard gemcitabine has been demonstrated in phase III-trials. Indeed nab-paclitaxel/gemcitabine has a more favorable toxicity profile compared to the FOLFIRINOX protocol and appears applicable in a perioperative setting. METHODS: NEONAX is an interventional, prospective, randomized, controlled, open label, two sided phase II study with an unconnected analysis of the results in both experimental arms against a fixed survival probability (38% at 18 months with adjuvant gemcitabine), NCT02047513. NEONAX will enroll 166 patients with resectable pancreatic ductal adenocarcinoma (≤ cT3, N0 or N1, cM0) in two arms: Arm A (perioperative arm): 2 cycles nab-paclitaxel (125 mg/m2)/gemcitabine (1000 mg/m2, d1, 8 and 15 of an 28 day-cycle) followed by tumor surgery followed by 4 cycles nab-paclitaxel/gemcitabine, Arm B (adjuvant arm): tumor surgery followed by 6 cycles nab-paclitaxel/gemcitabine. The randomization (1:1) is eminent to avoid allocation bias between the groups. Randomization is stratified for tumor stage (ct1/2 vs. cT3) and lymph node status (cN0 vs. cN1). Primary objective is disease free survival (DFS) at 18 months after randomization. Key secondary objectives are 3-year overall survival (OS) rate and DFS rate, progression during neoadjuvant therapy, R0 and R1 resection rate, quality of life and correlation of DFS, OS and tumor regression with pharmacogenomic markers, tumor biomarkers and molecular analyses (ctDNA, transcriptome, miRNA-arrays). In addition, circulating tumor-DNA will be analyzed in patients with the best and the worst responses to the neoadjuvant treatment. The study was initiated in March 2015 in 26 centers for pancreatic surgery in Germany. DISCUSSION: The NEONAX trial is an innovative study on resectable pancreatic cancer and currently one of the largest trials in this field of research. It addresses the question of the role of intensified perioperative treatment with nab-paclitaxel plus gemcitabine in resectable pancreatic cancers to improve disease-free survival and offers a unique potential for translational research. TRIAL REGISTRATION: ClinicalTrials.gov : NCT02047513, 08/13/2014.


Assuntos
Albuminas/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Ductal Pancreático/terapia , Desoxicitidina/análogos & derivados , Paclitaxel/uso terapêutico , Neoplasias Pancreáticas/terapia , Adulto , Idoso , Carcinoma Ductal Pancreático/mortalidade , Ensaios Clínicos Fase II como Assunto , Desoxicitidina/uso terapêutico , Progressão da Doença , Intervalo Livre de Doença , Combinação de Medicamentos , Fluoruracila/uso terapêutico , Alemanha/epidemiologia , Humanos , Leucovorina/uso terapêutico , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Terapia Neoadjuvante/métodos , Compostos Organometálicos/uso terapêutico , Pancreatectomia , Neoplasias Pancreáticas/mortalidade , Prognóstico , Estudos Prospectivos , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Análise de Sobrevida , Adulto Jovem
13.
Gastroenterology ; 2018 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-30296435

RESUMO

BACKGROUND AND AIMS: Cells in pancreatic ductal adenocarcinoma (PDAC) undergo autophagy, but its effects vary with tumor stage and genetic factors. We investigated the consequences of varying levels of the autophagy-related 5 (Atg5) protein on pancreatic tumor formation and progression. METHODS: We generated mice that express oncogenic Kras in primary pancreatic cancer cells and have homozygous disruption of Atg5 (A5;Kras) or heterozygous disruption of Atg5 (A5+/-;Kras), and compared them with mice with only oncogenic Kras (controls). Pancreata were analyzed by histology and immunohistochemistry. Primary tumor cells were isolated and used to perform transcriptome, metabolome, intracellular calcium, extracellular cathepsin activity, and cell migration and invasion analyses. The cells were injected into wild-type littermates, and orthotopic tumor growth and metastasis were monitored. Atg5 was knocked down in pancreatic cancer cell lines using small hairpin RNAs; cell migration and invasion were measured, and cells were injected into wild-type littermates. PDAC samples were obtained from independent cohorts of patients and protein levels were measured on immunoblot and immunohistochemistry; we tested the correlation of protein levels with metastasis and patient survival times. RESULTS: A5+/-;Kras mice, with reduced Atg5 levels, developed more tumors and metastases, than control mice, whereas A5;Kras mice did not develop any tumors. Cultured A5+/-;Kras primary tumor cells were resistant to induction and inhibition of autophagy, had altered mitochondrial morphology, compromised mitochondrial function, changes in intracellular Ca2+ oscillations, and increased activity of extracellular cathepsin L and D. The tumors that formed in A5+/-;Kras mice contained greater numbers of type 2 macrophages than control mice, and primary A5+/-;Kras tumor cells had up-regulated expression of cytokines that regulate macrophage chemoattraction and differentiation into M2 macrophage. Knockdown of Atg5 in pancreatic cancer cell lines increased their migratory and invasive capabilities, and formation of metastases following injection into mice. In human PDAC samples, lower levels of ATG5 associated with tumor metastasis and shorter survival time. CONCLUSIONS: In mice that express oncogenic Kras in pancreatic cells, heterozygous disruption of Atg5 and reduced protein levels promotes tumor development, whereas homozygous disruption of Atg5 blocks tumorigenesis. Therapeutic strategies to alter autophagy in PDAC should consider the effects of ATG5 levels to avoid the expansion of resistant and highly aggressive cells.

14.
FASEB J ; : fj201800985R, 2018 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-30207797

RESUMO

Tumor microvesicles are a peculiar type of extracellular vesicles that circulate in the blood of patients with metastatic cancer. The itineraries and immune cell interactions of tumor microvesicles during the intravascular and extravascular stages of metastasis are largely unknown. We found that the lipid receptor CD36 is a major mediator of the engulfment of pancreatic tumor microvesicles by myeloid immune cells in vitro and critically samples circulating tumor microvesicles by resident liver macrophages in mice in vivo. Direct nanoscopic imaging of individual tumor microvesicles shows that the microvesicles rapidly decay during engulfment whereby their cargo is targeted concomitantly to the plasma membrane and the cytoplasm excluding lysosomal compartments. CD36 also promotes internalization of blood cell (nontumor) microvesicles, which involves endolysosomal pathways. A portion of tumor microvesicles circulating in the liver microcirculation traverses the vessel wall in a CD36-dependent way. Extravasated microvesicles colonize distinct perivascular Ly6C- macrophages for at least 2 wk. Thus, the microvesicles are increasingly integrated into CD36-induced premetastatic cell clusters and enhance development of liver metastasis. Hence, promotion of metastasis by pancreatic tumor microvesicles is associated with CD36-regulated immune cell invasion and extravasation of microvesicles and persistent infiltration of specific tissue macrophages by microvesicle cargo.-Pfeiler, S., Thakur, M., Grünauer, P., Megens, R. T. A., Joshi, U., Coletti, R., Samara, V., Müller-Stoy, G., Ishikawa-Ankerhold, H., Stark, K., Klingl, A., Fröhlich, T., Arnold, G. J., Wörmann, S., Bruns, C. J., Algül, H., Weber, C., Massberg, S., Engelmann, B. CD36-triggered cell invasion and persistent tissue colonization by tumor microvesicles during metastasis.

15.
Front Immunol ; 9: 1878, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30158932

RESUMO

Pancreatic ductal adenocarcinoma (PDAC), as the most frequent form of pancreatic malignancy, still is associated with a dismal prognosis. Due to its late detection, most patients are ineligible for surgery, and chemotherapeutic options are limited. Tumor heterogeneity and a characteristic structure with crosstalk between the cancer/malignant cells and an abundant tumor microenvironment (TME) make PDAC a very challenging puzzle to solve. Thus far, targeted therapies have failed to substantially improve the overall survival of PDAC patients. Immune checkpoint inhibition, as an emerging therapeutic option in cancer treatment, shows promising results in different solid tumor types and hematological malignancies. However, PDAC does not respond well to immune checkpoint inhibitors anti-programmed cell death protein 1 (PD-1) or anti-cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) alone or in combination. PDAC with its immune-privileged nature, starting from the early pre-neoplastic state, appears to escape from the antitumor immune response unlike other neoplastic entities. Different mechanisms how cancer cells achieve immune-privileged status have been hypothesized. Among them are decreased antigenicity and impaired immunogenicity via both cancer cell-intrinsic mechanisms and an augmented immunosuppressive TME. Here, we seek to shed light on the recent advances in both bench and bedside investigation of immunotherapeutic options for PDAC. Furthermore, we aim to compile recent data about how PDAC adopts immune escape mechanisms, and how these mechanisms might be exploited therapeutically in combination with immune checkpoint inhibitors, such as PD-1 or CTLA-4 antibodies.

16.
Pancreatology ; 18(6): 630-634, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30017450

RESUMO

BACKGROUND AND OBJECTIVES: Candida infections are frequent in necrotising pancreatitis. Candidemia is associated with very high mortality and its risk due to infected pancreatic necrosis is unknown. So we aimed to assess potential risk factors and the risk of candidemia in necrotising pancreatitis. METHODS: We retrospectively searched our clinical database for the diagnosis necrotising pancreatitis from 2007 till March 2017 and entered relevant information in a database for statistical analysis. RESULTS: in total, 136 patients met the inclusion criteria. Candida infected pancreatic necrosis were found in 54 patients and 7 patients developed candidemia. Patients with Candida infected necrosis had a significantly higher in hospital mortality (35.2% versus 13.4%, p = 0.003). The highest mortality was observed in patients with candidemia (57.1% versus 20.2%, p = 0.042). Male gender (OR 0.32, CI 0.13-0.78, p = 0.013) and post-ERCP pancreatitis (OR 4.32, CI 1.01-18.36, p = 0.048) had a significant impact on the risk of Candida infections of pancreatic necrosis. Candidemia was significantly more frequent in patients with Candida infected necrosis (11.1% versus 1.2%, p = 0.016). Candida albicans was the most common species followed by Candida glabrata. CONCLUSION: Candidemia is a relevant complication of necrotising pancreatitis and associated with high mortality. If patients do not respond to antibiotic therapy empiric antifungal therapy should be discussed.

17.
Nat Med ; 24(7): 954-960, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29808009

RESUMO

The ubiquitously expressed non-receptor protein tyrosine phosphatase SHP2, encoded by PTPN11, is involved in signal transduction downstream of multiple growth factor, cytokine and integrin receptors1. Its requirement for complete RAS-MAPK activation and its role as a negative regulator of JAK-STAT signaling have established SHP2 as an essential player in oncogenic signaling pathways1-7. Recently, a novel potent allosteric SHP2 inhibitor was presented as a viable therapeutic option for receptor tyrosine kinase-driven cancers, but was shown to be ineffective in KRAS-mutant tumor cell lines in vitro8. Here, we report a central and indispensable role for SHP2 in oncogenic KRAS-driven tumors. Genetic deletion of Ptpn11 profoundly inhibited tumor development in mutant KRAS-driven murine models of pancreatic ductal adenocarcinoma and non-small-cell lung cancer. We provide evidence for a critical dependence of mutant KRAS on SHP2 during carcinogenesis. Deletion or inhibition of SHP2 in established tumors delayed tumor progression but was not sufficient to achieve tumor regression. However, SHP2 was necessary for resistance mechanisms upon blockade of MEK. Synergy was observed when both SHP2 and MEK were targeted, resulting in sustained tumor growth control in murine and human patient-derived organoids and xenograft models of pancreatic ductal adenocarcinoma and non-small-cell lung cancer. Our data indicate the clinical utility of dual SHP2/MEK inhibition as a targeted therapy approach for KRAS-mutant cancers.

18.
Hepatobiliary Pancreat Dis Int ; 17(1): 49-54, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29428104

RESUMO

BACKGROUND: Occlusion of self-expanding metal stents (SEMS) in malignant biliary obstruction occurs in up to 40% of patients. This study aimed to compare the different techniques to resolve stent occlusion in our collective of patients. METHODS: Patients with malignant biliary obstruction and occlusion of biliary metal stent at a tertiary referral endoscopic center were retrospectively identified between April 1, 1994 and May 31, 2014. The clinical records were further analyzed regarding the characteristics of patients, malignant strictures, SEMS, management strategies, stent patency, subsequent interventions, survival time and case charges. RESULTS: A total of 108 patients with biliary metal stent occlusion were identified. Seventy-nine of these patients were eligible for further analysis. Favored management was plastic stent insertion in 73.4% patients. Second SEMS were inserted in 12.7% patients. Percutaneous transhepatic biliary drainage and mechanical cleansing were conducted in a minority of patients. Further analysis showed no statistically significant difference in median overall secondary stent patency (88 vs. 143 days, P = 0.069), median survival time (95 vs. 192 days, P = 0.116), median subsequent intervention rate (53.4% vs. 40.0%, P = 0.501) and median case charge (€5145 vs. €3473, P = 0.803) for the treatment with a second metal stent insertion compared to plastic stent insertion. In patients with survival time of more than three months, significantly more patients treated with plastic stents needed re-interventions than patients treated with second SEMS (93.3% vs. 57.1%, P = 0.037). CONCLUSIONS: In malignant biliary strictures, both plastic and metal stent insertions are feasible strategies for the treatment of occluded SEMS. Our data suggest that in palliative biliary stenting, patients especially those with longer expected survival might benefit from second SEMS insertion. Careful patient selection is important to ensure a proper decision for either management strategy.


Assuntos
Colangiopancreatografia Retrógrada Endoscópica/instrumentação , Colestase/terapia , Neoplasias do Sistema Digestório/complicações , Drenagem/instrumentação , Stents Metálicos Autoexpansíveis , Idoso , Colangiopancreatografia Retrógrada Endoscópica/efeitos adversos , Colangiopancreatografia Retrógrada Endoscópica/economia , Colestase/diagnóstico por imagem , Colestase/economia , Colestase/etiologia , Tomada de Decisão Clínica , Análise Custo-Benefício , Neoplasias do Sistema Digestório/diagnóstico , Drenagem/efeitos adversos , Drenagem/economia , Estudos de Viabilidade , Feminino , Custos Hospitalares , Humanos , Masculino , Pessoa de Meia-Idade , Cuidados Paliativos , Seleção de Pacientes , Plásticos , Desenho de Prótese , Falha de Prótese , Estudos Retrospectivos , Fatores de Risco , Stents Metálicos Autoexpansíveis/economia , Centros de Atenção Terciária , Fatores de Tempo , Resultado do Tratamento
19.
Arterioscler Thromb Vasc Biol ; 38(4): 772-786, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29419408

RESUMO

OBJECTIVE: Cancer patients are at high risk of developing deep venous thrombosis (DVT) and venous thromboembolism, a leading cause of mortality in this population. However, it is largely unclear how malignant tumors drive the prothrombotic cascade culminating in DVT. APPROACH AND RESULTS: Here, we addressed the pathophysiology of malignant DVT compared with nonmalignant DVT and focused on the role of tumor microvesicles as potential targets to prevent cancer-associated DVT. We show that microvesicles released by pancreatic adenocarcinoma cells (pancreatic tumor-derived microvesicles [pcMV]) boost thrombus formation in a model of flow restriction of the mouse vena cava. This depends on the synergistic activation of coagulation by pcMV and host tissue factor. Unlike nonmalignant DVT, which is initiated and propagated by innate immune cells, thrombosis triggered by pcMV was largely independent of myeloid leukocytes or platelets. Instead, we identified externalization of the phospholipid phosphatidylethanolamine as a major mechanism controlling the prothrombotic activity of pcMV. Disrupting phosphatidylethanolamine-dependent activation of factor X suppressed pcMV-induced DVT without causing changes in hemostasis. CONCLUSIONS: Together, we show here that the pathophysiology of pcMV-associated experimental DVT differs markedly from innate immune cell-promoted nonmalignant DVT and is therefore amenable to distinct antithrombotic strategies. Targeting phosphatidylethanolamine on tumor microvesicles could be a new strategy for prevention of cancer-associated DVT without causing bleeding complications.

20.
Gut ; 67(10): 1855-1863, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-28754779

RESUMO

OBJECTIVE: Alcohol-related pancreatitis is associated with a disproportionately large number of hospitalisations among GI disorders. Despite its clinical importance, genetic susceptibility to alcoholic chronic pancreatitis (CP) is poorly characterised. To identify risk genes for alcoholic CP and to evaluate their relevance in non-alcoholic CP, we performed a genome-wide association study and functional characterisation of a new pancreatitis locus. DESIGN: 1959 European alcoholic CP patients and population-based controls from the KORA, LIFE and INCIPE studies (n=4708) as well as chronic alcoholics from the GESGA consortium (n=1332) were screened with Illumina technology. For replication, three European cohorts comprising 1650 patients with non-alcoholic CP and 6695 controls originating from the same countries were used. RESULTS: We replicated previously reported risk loci CLDN2-MORC4, CTRC, PRSS1-PRSS2 and SPINK1 in alcoholic CP patients. We identified CTRB1-CTRB2 (chymotrypsin B1 and B2) as a new risk locus with lead single-nucleotide polymorphism (SNP) rs8055167 (OR 1.35, 95% CI 1.23 to 1.6). We found that a 16.6 kb inversion in the CTRB1-CTRB2 locus was in linkage disequilibrium with the CP-associated SNPs and was best tagged by rs8048956. The association was replicated in three independent European non-alcoholic CP cohorts of 1650 patients and 6695 controls (OR 1.62, 95% CI 1.42 to 1.86). The inversion changes the expression ratio of the CTRB1 and CTRB2 isoforms and thereby affects protective trypsinogen degradation and ultimately pancreatitis risk. CONCLUSION: An inversion in the CTRB1-CTRB2 locus modifies risk for alcoholic and non-alcoholic CP indicating that common pathomechanisms are involved in these inflammatory disorders.


Assuntos
Quimotripsina/genética , Pancreatite Alcoólica , Adulto , Idoso , Europa (Continente)/epidemiologia , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Pancreatite Alcoólica/epidemiologia , Pancreatite Alcoólica/genética , Polimorfismo de Nucleotídeo Único
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