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1.
bioRxiv ; 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38168289

RESUMO

Cellular plasticity is a hallmark of pancreatic ductal adenocarcinoma (PDAC) starting from the conversion of normal cells into precancerous lesions to the progression of carcinoma subtypes associated with aggressiveness and therapeutic response. We discovered that normal acinar cell differentiation, maintained by the transcription factor Pdx1, suppresses a broad gastric cell identity that is maintained in metaplasia, neoplasia, and the classical subtype of PDAC in mouse and human. We have identified the receptor tyrosine kinase Ror2 as marker of a gastric metaplasia (SPEM)-like identity in the pancreas. Ablation of Ror2 in a mouse model of pancreatic tumorigenesis promoted a switch to a gastric pit cell identity that largely persisted through progression to the classical subtype of PDAC. In both human and mouse pancreatic cancer, ROR2 activity continued to antagonize the gastric pit cell identity, strongly promoting an epithelial to mesenchymal transition, conferring resistance to KRAS inhibition, and vulnerability to AKT inhibition.

2.
Aging Dis ; 15(1): 338-356, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37307826

RESUMO

Primary sclerosing cholangitis (PSC) represents a chronic liver disease characterized by poor prognosis and lacking causal treatment options. Yes-associated protein (YAP) functions as a critical mediator of fibrogenesis; however, its therapeutic potential in chronic biliary diseases such as PSC remains unestablished. The objective of this study is to elucidate the possible significance of YAP inhibition in biliary fibrosis by examining the pathophysiology of hepatic stellate cells (HSC) and biliary epithelial cells (BEC). Human liver tissue samples from PSC patients were analyzed to assess the expression of YAP/connective tissue growth factor (CTGF) relative to non-fibrotic control samples. The pathophysiological relevance of YAP/CTGF in HSC and BEC was investigated in primary human HSC (phHSC), LX-2, H69, and TFK-1 cell lines through siRNA or pharmacological inhibition utilizing verteporfin (VP) and metformin (MF). The Abcb4-/- mouse model was employed to evaluate the protective effects of pharmacological YAP inhibition. Hanging droplet and 3D matrigel culture techniques were utilized to investigate YAP expression and activation status of phHSC under various physical conditions. YAP/CTGF upregulation was observed in PSC patients. Silencing YAP/CTGF led to inhibition of phHSC activation and reduced contractility of LX-2 cells, as well as suppression of epithelial-mesenchymal transition (EMT) in H69 cells and proliferation of TFK-1 cells. Pharmacological inhibition of YAP mitigated chronic liver fibrosis in vivo and diminished ductular reaction and EMT. YAP expression in phHSC was effectively modulated by altering extracellular stiffness, highlighting YAP's role as a mechanotransducer. In conclusion, YAP regulates the activation of HSC and EMT in BEC, thereby functioning as a checkpoint of fibrogenesis in chronic cholestasis. Both VP and MF demonstrate effectiveness as YAP inhibitors, capable of inhibiting biliary fibrosis. These findings suggest that VP and MF warrant further investigation as potential therapeutic options for the treatment of PSC.


Assuntos
Colestase , Células Estreladas do Fígado , Camundongos , Animais , Humanos , Cirrose Hepática/tratamento farmacológico , Fibrose , Colestase/metabolismo , Ductos Biliares , Epitélio/metabolismo
3.
Gastroenterology ; 163(5): 1407-1422, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35870514

RESUMO

BACKGROUND & AIMS: Pancreatic ductal adenocarcinoma cancer (PDAC) is a highly lethal malignancy requiring efficient detection when the primary tumor is still resectable. We previously developed the MxPancreasScore comprising 9 analytes and serum carbohydrate antigen 19-9 (CA19-9), achieving an accuracy of 90.6%. The necessity for 5 different analytical platforms and multiple analytical runs, however, hindered clinical applicability. We therefore aimed to develop a simpler single-analytical run, single-platform diagnostic signature. METHODS: We evaluated 941 patients (PDAC, 356; chronic pancreatitis [CP], 304; nonpancreatic disease, 281) in 3 multicenter independent tests, and identification (ID) and validation cohort 1 (VD1) and 2 (VD2) were evaluated. Targeted quantitative plasma metabolite analysis was performed on a liquid chromatography-tandem mass spectrometry platform. A machine learning-aided algorithm identified an improved (i-Metabolic) and minimalistic metabolic (m-Metabolic) signatures, and compared them for performance. RESULTS: The i-Metabolic Signature, (12 analytes plus CA19-9) distinguished PDAC from CP with area under the curve (95% confidence interval) of 97.2% (97.1%-97.3%), 93.5% (93.4%-93.7%), and 92.2% (92.1%-92.3%) in the ID, VD1, and VD2 cohorts, respectively. In the VD2 cohort, the m-Metabolic signature (4 analytes plus CA19-9) discriminated PDAC from CP with a sensitivity of 77.3% and specificity of 89.6%, with an overall accuracy of 82.4%. For the subset of 45 patients with PDAC with resectable stages IA-IIB tumors, the sensitivity, specificity, and accuracy were 73.2%, 89.6%, and 82.7%, respectively; for those with detectable CA19-9 >2 U/mL, 81.6%, 88.7%, and 84.5%, respectively; and for those with CA19-9 <37 U/mL, 39.7%, 94.1%, and 76.3%, respectively. CONCLUSIONS: The single-platform, single-run, m-Metabolic signature of just 4 metabolites used in combination with serum CA19-9 levels is an innovative accurate diagnostic tool for PDAC at the time of clinical presentation, warranting further large-scale evaluation.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Pancreatite Crônica , Humanos , Antígeno CA-19-9 , Biomarcadores Tumorais , Curva ROC , Estudos de Casos e Controles , Carcinoma Ductal Pancreático/patologia , Neoplasias Pancreáticas/patologia , Pancreatite Crônica/diagnóstico , Padrões de Referência , Carboidratos , Neoplasias Pancreáticas
4.
Pancreatology ; 22(5): 644-650, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35589512

RESUMO

BACKGROUND: Current guidelines provide weak recommendations to treat small (<2 cm) non-functional pancreatic neuroendocrine tumors with low Ki-67 proliferation index either by resection or clinical follow-up. However, there is a lack of consensus regarding the minimal size of pNET, which allows EUS-guided biopsy with high enough diagnostic accuracy for stratification. METHODS: We conducted a retrospective, bicentric analysis of patients who had undergone EUS-guided pNET sampling in two tertiary care Endoscopy Units in Germany and Poland. Using a recursive partitioning of the tree-aided model, we aimed to stratify the probability of successful EUS-guided biopsy of pNET lesions according to their size and location. RESULTS: In our pNET cohort, successful histological confirmation of a pNET diagnosis was achieved in 59/69 (85.5%) cases at the initial EUS-guided biopsy. In 41 patients with a pNET size less than 18.5 mm, the EUS-guided first biopsy was successful in 90.2%. In 16 of these patients with smaller lesions, EUS-guided sampling was 100% in very small (less than 11 mm) and extremely small lesions (less than 8 mm). The biopsy success rate was 100% in tail lesions in the size range between ≥5.95 and <8.1 mm but only 33.3% independent of the investigator in pancreatic head or body, with an error rate of 11.2% CONCLUSION: Using a recursive partitioning of the tree-aided stratification model, we demonstrate for the first time that in balancing risks and benefits, very small pNETs (<1 cm) in the tail of the pancreas should be sampled under EUS-guidance.


Assuntos
Tumores Neuroectodérmicos Primitivos , Tumores Neuroendócrinos , Neoplasias Pancreáticas , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico , Humanos , Tumores Neuroendócrinos/patologia , Neoplasias Pancreáticas/patologia , Estudos Retrospectivos
5.
JCI Insight ; 7(10)2022 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-35439169

RESUMO

Systemic therapies for pancreatic ductal adenocarcinoma (PDAC) remain unsatisfactory. Clinical prognosis is particularly poor for tumor subtypes with activating aberrations in the MYC pathway, creating an urgent need for novel therapeutic targets. To unbiasedly find MYC-associated epigenetic dependencies, we conducted a drug screen in pancreatic cancer cell lines. Here, we found that protein arginine N-methyltransferase 5 (PRMT5) inhibitors triggered an MYC-associated dependency. In human and murine PDACs, a robust connection of MYC and PRMT5 was detected. By the use of gain- and loss-of-function models, we confirmed the increased efficacy of PRMT5 inhibitors in MYC-deregulated PDACs. Although inhibition of PRMT5 was inducing DNA damage and arresting PDAC cells in the G2/M phase of the cell cycle, apoptotic cell death was executed predominantly in cells with high MYC expression. Experiments in primary patient-derived PDAC models demonstrated the existence of a highly PRMT5 inhibitor-sensitive subtype. Our work suggests developing PRMT5 inhibitor-based therapies for PDAC.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Animais , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Avaliação Pré-Clínica de Medicamentos , Detecção Precoce de Câncer , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Epigênese Genética , Humanos , Camundongos , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Proteína-Arginina N-Metiltransferases/genética , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Neoplasias Pancreáticas
7.
Gastroenterology ; 161(3): 996-1010.e1, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34097885

RESUMO

BACKGROUNDS & AIMS: Fluoropyrimidine c (5-fluorouracil [5FU]) increasingly represents the chemotherapeutic backbone for neoadjuvant, adjuvant, and palliative treatment of pancreatic ductal adenocarcinoma (PDAC). Even in combination with other agents, 5FU efficacy remains transient and limited. One explanation for the inadequate response is insufficient and nonspecific delivery of 5FU to the tumor. METHODS: We designed, generated, and characterized 5FU-incorporated systematic evolution of ligands by exponential enrichment (SELEX)-selected epidermal growth factor receptor (EGFR)-targeted aptamers for tumor-specific delivery of 5FU to PDAC cells and tested their therapeutic efficacy in vitro and in vivo. RESULTS: 5FU-EGFR aptamers reduced proliferation in a concentration-dependent manner in mouse and human pancreatic cancer cell lines. Time-lapsed live imaging showed EGFR-specific uptake of aptamers via clathrin-dependent endocytosis. The 5FU-aptamer treatment was equally effective in 5FU-sensitive and 5FU-refractory PDAC cell lines. Biweekly treatment with 5FU-EGFR aptamers reduced tumor burden in a syngeneic orthotopic transplantation model of PDAC, in an autochthonously growing genetically engineered PDAC model (LSL-KrasG12D/+;LSL-Trp53flox/+;Ptf1a-Cre [KPC]), in an orthotopic cell line-derived xenograft model using human PDAC cells in athymic mice (CDX; Crl:NU-Foxn1nu), and in patient-derived organoids. Tumor growth was significantly attenuated during 5FU-EGFR aptamer treatment in the course of follow-up. CONCLUSIONS: Tumor-specific targeted delivery of 5FU using EGFR aptamers as the carrier achieved high target specificity; overcame 5FU resistance; and proved to be effective in a syngeneic orthotopic transplantation model, in KPC mice, in a CDX model, and in patient-derived organoids and, therefore, represents a promising backbone for pancreatic cancer chemotherapy in patients. Furthermore, our approach has the potential to target virtually any cancer entity sensitive to 5FU treatment by incorporating 5FU into cancer cell-targeting aptamers as the delivery platform.


Assuntos
Antimetabólitos Antineoplásicos/administração & dosagem , Aptâmeros de Nucleotídeos/administração & dosagem , Carcinoma Ductal Pancreático/tratamento farmacológico , Sistemas de Liberação de Medicamentos , Receptores ErbB/metabolismo , Fluoruracila/administração & dosagem , Neoplasias Pancreáticas/tratamento farmacológico , Animais , Antimetabólitos Antineoplásicos/metabolismo , Aptâmeros de Nucleotídeos/metabolismo , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos , Endocitose , Receptores ErbB/genética , Feminino , Fluoruracila/metabolismo , Humanos , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Organoides , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Técnica de Seleção de Aptâmeros , Carga Tumoral/efeitos dos fármacos , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
8.
J Cell Mol Med ; 25(10): 4658-4670, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33682322

RESUMO

Mutations in the cystic fibrosis transmembrane conductance regulator gene (CFTR) are an established risk factor for cystic fibrosis (CF) and chronic pancreatitis. Whereas patients with CF usually develop complete exocrine pancreatic insufficiency, pancreatitis patients with CFTR mutations have mostly preserved exocrine pancreatic function. We therefore used a strain of transgenic mice with significant residual CFTR function (CFTRtm1HGU ) to induce pancreatitis experimentally by serial caerulein injections. Protease activation and necrosis were investigated in isolated acini, disease severity over 24h, pancreatic function by MRI, isolated duct stimulation and faecal chymotrypsin, and leucocyte function by ex vivo lipopolysaccharide (LPS) stimulation. Pancreatic and lung injury were more severe in CFTRtm1HGU but intrapancreatic trypsin and serum enzyme activities higher than in wild-type controls only at 8h, a time interval previously attributed to leucocyte infiltration. CCK-induced trypsin activation and necrosis in acini from CFTRtm1HGU did not differ from controls. Fluid and bicarbonate secretion were greatly impaired, whereas faecal chymotrypsin remained unchanged. LPS stimulation of splenocytes from CFTRtm1HGU resulted in increased INF-γ and IL-6, but decreased IL-10 secretion. CFTR mutations that preserve residual pancreatic function significantly increase the severity of experimental pancreatitis-mostly via impairing duct cell function and a shift towards a pro-inflammatory phenotype, not by rendering acinar cells more susceptible to pathological stimuli.


Assuntos
Células Acinares/citologia , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Fibrose Cística/complicações , Inflamação/patologia , Mutação , Ductos Pancreáticos/patologia , Pancreatite/patologia , Células Acinares/metabolismo , Animais , Cloretos/metabolismo , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Humanos , Inflamação/etiologia , Inflamação/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Ductos Pancreáticos/metabolismo , Pancreatite/etiologia , Pancreatite/metabolismo , Índice de Gravidade de Doença
9.
Gut ; 70(11): 2150-2158, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33541865

RESUMO

OBJECTIVE: Chronic pancreatitis (CP) is a fibroinflammatory syndrome leading to organ dysfunction, chronic pain, an increased risk for pancreatic cancer and considerable morbidity. Due to a lack of specific biomarkers, diagnosis is based on symptoms and specific but insensitive imaging features, preventing an early diagnosis and appropriate management. DESIGN: We conducted a type 3 study for multivariable prediction for individual prognosis according to the TRIPOD guidelines. A signature to distinguish CP from controls (n=160) was identified using gas chromatography-mass spectrometry and liquid chromatography-tandem mass spectrometry on ethylenediaminetetraacetic acid (EDTA)-plasma and validated in independent cohorts. RESULTS: A Naive Bayes algorithm identified eight metabolites of six ontology classes. After algorithm training and computation of optimal cut-offs, classification according to the metabolic signature detected CP with an area under the curve (AUC) of 0.85 ((95% CI 0.79 to 0.91). External validation in two independent cohorts (total n=502) resulted in similar accuracy for detection of CP compared with non-pancreatic controls in EDTA-plasma (AUC 0.85 (95% CI 0.81 to 0.89)) and serum (AUC 0.87 (95% CI 0.81 to 0.95)). CONCLUSIONS: This is the first study that identifies and independently validates a metabolomic signature in plasma and serum for the diagnosis of CP in large, prospective cohorts. The results could provide the basis for the development of the first routine laboratory test for CP.


Assuntos
Metabolômica , Pancreatite Crônica/sangue , Plasma , Teorema de Bayes , Biomarcadores/sangue , Estudos de Casos e Controles , Cromatografia Gasosa , Cromatografia Líquida , Feminino , Humanos , Masculino , Espectrometria de Massas , Valor Preditivo dos Testes , Prognóstico , Estudo de Prova de Conceito
10.
Dig Dis ; 39(1): 42-51, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32521535

RESUMO

INTRODUCTION AND OBJECTIVE: Acute cholangitis is a life-threatening condition. The early initiation of antibiotic therapy significantly impacts the course of disease. Only few data are available on distribution and resistance profiles of bile pathogens. Here, we report on an analysis of routinely acquired bile specimens and provide an overview of the prevalence, resistance rates, and risk factors for the presence of pathogens in bile. METHODS: Bile cultures obtained from 388 endoscopic retrograde cholangiographies (ERCs) with corresponding clinical data were analysed in 208 patients. RESULTS: The majority (84.8%) of cultures yielded positive for at least 1 organism. Abundance was highest for Enterococcus faecalis, Enterococcus faecium, and Escherichia coli. Multiresistant organisms were present in 14.9%. The initial antibiotic regimen was changed in 44.1%, which increased the length of hospital stay significantly (***p < 0.001). Pre-existing papillotomy (EPT) or biliary drainage was associated with higher frequency of bile pathogens (**p < 0.01) in a univariate analysis. Multivariate analysis confirmed these results for EPT and revealed significantly more positive results for pathogens, gram-negative bacteria, and fungi in patients with biliary drainage. Significant differences in the prevalence of pathogens were observed between relevant subgroups of ERC indications. The highest susceptibility rates were observed for linezolid and tigecycline in gram-positive bacteria and for meropenem and gentamicin in gram-negative bacteria. CONCLUSIONS: Our study provides a comprehensive analysis of the distribution, resistance profiles, and risk factors for the detection of bile pathogens. The frequent change in initial antibiotic treatment highlights the importance of routine bile culture and indicates that current schemas of empirical treatment might not cover the contemporary spectrum of pathogens in bile.


Assuntos
Bile/microbiologia , Colangiopancreatografia Retrógrada Endoscópica , Resistência Microbiana a Medicamentos , Antibacterianos/uso terapêutico , Bactérias/isolamento & purificação , Ductos Biliares/cirurgia , Drenagem , Feminino , Fungos/isolamento & purificação , Humanos , Tempo de Internação , Testes de Sensibilidade Microbiana , Prevalência , Fatores de Risco
11.
JNCI Cancer Spectr ; 4(1): pkz060, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32296755

RESUMO

BACKGROUND: Cathepsin-D (CatD), owing to its dual role as a proteolytic enzyme and as a ligand, has been implicated in cancer progression. The role of CatD in pancreatic ductal adenocarcinoma is unknown. METHODS: CatD expression quantified by immunohistochemistry of tumor-tissue microarrays of 403 resected pancreatic cancer patients from the ESPAC-Tplus trial, a translational study within the ESPAC (European Study Group for Pancreatic Cancer) trials, was dichotomously distributed to low and high H scores (cut off 22.35) for survival and multivariable analysis. The validation cohort (n = 69) was recruited based on the hazard ratio of CatD from ESPAC-Tplus. 5-fluorouracil-, and gemcitabine-resistant pancreatic cancer cell lines were employed for mechanistic experiments. All statistical tests were two-sided. RESULTS: Median overall survival was 23.75 months and median overall survival for patients with high CatD expression was 21.09 (95% confidence interval [CI] = 17.31 to 24.80) months vs 27.20 (95% CI = 23.75 to 31.90) months for low CatD expression (χ2 LR, 1DF = 4.00; P = .04). Multivariable analysis revealed CatD expression as a predictive marker in gemcitabine-treated (z stat = 2.33; P = .02) but not in 5-fluorouracil-treated (z stat = 0.21; P = .82) patients. An independent validation cohort confirmed CatD as a negative predictive marker for survival (χ2 LR, 1DF = 6.80; P = .009) and as an independent predictive marker in gemcitabine-treated patients with a hazard ratio of 3.38 (95% CI = 1.36 to 8.38, P = .008). Overexpression of CatD was associated with a concomitant suppression of the acid sphingomyelinase, and silencing of CatD resulted in upregulation of acid sphingomyelinase with rescue of gemcitabine resistance. CONCLUSIONS: Adjuvant gemcitabine is less effective in pancreatic ductal adenocarcinoma with high CatD expression, and thus CatD could serve as a marker for biomarker-driven therapy.

12.
Cell Mol Life Sci ; 77(9): 1811-1825, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31363815

RESUMO

Premature intrapancreatic trypsinogen activation is widely regarded as an initiating event for acute pancreatitis. Previous studies have alternatively implicated secretory vesicles, endosomes, lysosomes, or autophagosomes/autophagolysosomes as the primary site of trypsinogen activation, from which a cell-damaging proteolytic cascade originates. To identify the subcellular compartment of initial trypsinogen activation we performed a time-resolution analysis of the first 12 h of caerulein-induced pancreatitis in transgenic light chain 3 (LC3)-GFP autophagy reporter mice. Intrapancreatic trypsin activity increased within 60 min and serum amylase within 2 h, but fluorescent autophagosome formation only by 4 h of pancreatitis in parallel with a shift from cytosolic LC3-I to membranous LC3-II on Western blots. At 60 min, activated trypsin in heavier subcellular fractions was co-distributed with cathepsin B, but not with the autophagy markers LC3 or autophagy protein 16 (ATG16). Supramaximal caerulein stimulation of primary pancreatic acini derived from LC3-GFP mice revealed that trypsinogen activation is independent of autophagolysosome formation already during the first 15 min of exposure to caerulein. Co-localization studies (with GFP-LC3 autophagosomes versus Ile-Pro-Arg-AMC trypsin activity and immunogold-labelling of lysosomal-associated membrane protein 2 [LAMP-2] versus trypsinogen activation peptide [TAP]) indicated active trypsin in autophagolysosomes only at the later timepoints. In conclusion, during the initiating phase of caerulein-induced pancreatitis, premature protease activation develops independently of autophagolysosome formation and in vesicles arising from the secretory pathway. However, autophagy is likely to regulate overall intracellular trypsin activity during the later stages of this disease.


Assuntos
Autofagia , Ceruletídeo/toxicidade , Pancreatite/patologia , Tripsina/metabolismo , Tripsinogênio/metabolismo , Animais , Autofagossomos/metabolismo , Endossomos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pancreatite/induzido quimicamente , Pancreatite/metabolismo , Vesículas Secretórias/metabolismo
13.
Biochim Biophys Acta Proteins Proteom ; 1868(1): 140281, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31525466

RESUMO

One of the most common mutations in the serine protease inhibitor Kazal type 1 (SPINK1) gene is the N34S variant which is strongly associated with chronic pancreatitis. Although it is assumed that N34S mutation constitutes a high-risk factor, the underlying pathologic mechanism is still unknown. In the present study, we investigated the impact of physiological stress factors on SPINK1 protein structure and trypsin inhibitor function using biophysical methods. Our circular dichroism spectroscopy data revealed differences in the secondary structure of SPINK1 and N34S mutant suggesting protein structural changes induced by the mutation as an impairment that could be disease-relevant. We further confirmed that both SPINK1 (KD of 0.15 ±â€¯0.06 nM) and its N34S variant (KD of 0.08 ±â€¯0.02 nM) have similar binding affinity and inhibitory effect towards trypsin as shown by surface plasmon resonance and trypsin inhibition assay studies, respectively. We found that stress conditions such as altered ion concentrations (i.e. potassium, calcium), temperature shifts, as well as environmental pH lead to insignificant differences in trypsin inhibition between SPINK1 and N34S mutant. However, we have shown that the environmental pH induces structural changes in both SPINK1 constructs in a different manner. Our findings suggest protein structural changes in the N34S variant as an impairment of SPINK1 and environmental pH shift as a trigger that could play a role in disease progression of pancreatitis.


Assuntos
Estresse Fisiológico , Inibidor da Tripsina Pancreática de Kazal/química , Tripsina/química , Progressão da Doença , Células HEK293 , Humanos , Concentração de Íons de Hidrogênio , Mutação , Pancreatite , Conformação Proteica , Temperatura , Inibidor da Tripsina Pancreática de Kazal/genética
14.
Gastroenterol. hepatol. (Ed. impr.) ; 42(9): 534-541, nov. 2019. ilus, graf, tab
Artigo em Inglês | IBECS | ID: ibc-187914

RESUMO

Introduction and aim: Thromboxane (TX) A2 was identified as an important vasoconstrictor during Zymosan induced portal perfusion pressure (PP) increase. We aimed at investigating whether hepatic steatosis influences the extent of TXA2-induced portal hypertension. Materials and methods: Sprague-Dawley rats were randomly divided into control and steatosis (induced by the special diet) groups. PP and TXB2 (stable degradation product of TXA2) in the perfusate were measured after in situ liver perfusion with Zymosan (150μg/ml, 40-46min) or U46619 (TXA2 analog, 0.1μM/ml, 40-46min). The number of Kupffer cell (KC) was measured by immunohistochemistry with CD163. Results: Zymosan induced more TXB2 production and a higher PP increase in control group than in steatosis group despite more CD163 positive KCs in fatty livers. PP and TXB2 efflux revealed a strong correlation in control group and a moderate correlation in steatosis group. Contrary to the effect of Zymosan, U46619 induced a much higher PP increase in steatosis group than in control group. Conclusion: Severe steatosis increased number of KCs, however, PP increase and TXB2 efflux caused by Zymosan infusion in fatty livers were lower than those in healthy livers. In contrast, TXA2 analog caused higher PP increase in fatty livers. Targeting the more sensitive response to TXA2 in fatty livers might be a potential therapy of severe steatosis


Introducción y objetivos: Se ha identificado al tromboxano (TX) A2 como importante vasoconstrictor durante el aumento de la presión de perfusión portal (PP) inducida por zymosan. El objetivo ha sido analizar si la esteatosis hepática influye en el grado de hipertensión portal inducida por TXA2. Materiales y métodos: Las ratas Sprague-Dawley(R) se han dividido aleatoriamente en grupos de control y esteatosis (inducida por una dieta especial). Se midieron la PP y el TXB2 (producto de degradación estable de TXA2) en la perfusión después de la perfusión hepática in situ de zymosan (150μg/ml, minuto 40-46) o U46619 (análogo de TXA2, 0,1μM/ml, minuto 40-46). El número de células de Kupffer (CK) se midió mediante inmunohistoquímica con CD163. Resultados: Zymosan provocó más producción de TXB2 y mayor aumento de la PP en el grupo de control que en el grupo de esteatosis a pesar de hallar más CK positivas para CD163 en hígados grasos. El flujo de salida de la PP y el TXB2 reveló una fuerte correlación en el grupo de control y una correlación moderada en el grupo de esteatosis. De manera diferente al efecto de zymosan, U46619 indujo un aumento de la PP mucho mayor en el grupo de esteatosis que en el grupo de control. Conclusión: La esteatosis grave aumentó el número de CK; sin embargo, el aumento de la PP y el flujo de TXB2 provocado por la perfusión de zymosan en hígados grasos fueron menores que en los hígados sanos. En cambio, el análogo de TXA2 provocó un aumento de la PP en hígados grasos. Centrarse en la respuesta más sensible al TXA2 en hígados grasos podría convertirse en un tratamiento potencial de la esteatosis grave


Assuntos
Animais , Ratos , Fígado Gorduroso/complicações , Hipertensão Portal/induzido quimicamente , Pressão na Veia Porta/efeitos dos fármacos , Tromboxano B2/biossíntese , Zimosan/farmacologia , Ácido 15-Hidroxi-11 alfa,9 alfa-(epoximetano)prosta-5,13-dienoico/farmacologia , Antígenos CD/análise , Antígenos de Diferenciação Mielomonocítica/análise , Fígado Gorduroso/patologia , Fígado Gorduroso/fisiopatologia , Células de Kupffer/química , Células de Kupffer/citologia , Perfusão/métodos , Pressão na Veia Porta/fisiologia , Tromboxano A2/análogos & derivados , Ratos Sprague-Dawley
15.
Gastroenterol Hepatol ; 42(9): 534-541, 2019 Nov.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-31326104

RESUMO

INTRODUCTION AND AIM: Thromboxane (TX) A2 was identified as an important vasoconstrictor during Zymosan induced portal perfusion pressure (PP) increase. We aimed at investigating whether hepatic steatosis influences the extent of TXA2-induced portal hypertension. MATERIALS AND METHODS: Sprague-Dawley rats were randomly divided into control and steatosis (induced by the special diet) groups. PP and TXB2 (stable degradation product of TXA2) in the perfusate were measured after in situ liver perfusion with Zymosan (150µg/ml, 40-46min) or U46619 (TXA2 analog, 0.1µM/ml, 40-46min). The number of Kupffer cell (KC) was measured by immunohistochemistry with CD163. RESULTS: Zymosan induced more TXB2 production and a higher PP increase in control group than in steatosis group despite more CD163 positive KCs in fatty livers. PP and TXB2 efflux revealed a strong correlation in control group and a moderate correlation in steatosis group. Contrary to the effect of Zymosan, U46619 induced a much higher PP increase in steatosis group than in control group. CONCLUSION: Severe steatosis increased number of KCs, however, PP increase and TXB2 efflux caused by Zymosan infusion in fatty livers were lower than those in healthy livers. In contrast, TXA2 analog caused higher PP increase in fatty livers. Targeting the more sensitive response to TXA2 in fatty livers might be a potential therapy of severe steatosis.


Assuntos
Fígado Gorduroso/complicações , Hipertensão Portal/induzido quimicamente , Pressão na Veia Porta/efeitos dos fármacos , Tromboxano B2/biossíntese , Zimosan/farmacologia , Ácido 15-Hidroxi-11 alfa,9 alfa-(epoximetano)prosta-5,13-dienoico/farmacologia , Animais , Antígenos CD/análise , Antígenos de Diferenciação Mielomonocítica/análise , Contagem de Células , Dieta Hiperlipídica , Fígado Gorduroso/patologia , Fígado Gorduroso/fisiopatologia , Células de Kupffer/química , Células de Kupffer/citologia , Perfusão/métodos , Pressão na Veia Porta/fisiologia , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Receptores de Superfície Celular/análise , Tromboxano A2/análogos & derivados , Tromboxano B2/análise , Vasoconstritores
16.
Dtsch Med Wochenschr ; 143(15): 1109-1112, 2018 08.
Artigo em Alemão | MEDLINE | ID: mdl-30060283

RESUMO

In Germany, an estimated 19 000 people will develop pancreatic carcinoma in 2018. The 5-year survival rate of all pancreatic carcinoma patients is very low at around 6 %, and the potentially curative operation is only possible in 15 - 20 % of patients. More frequent use and combination of systemic chemotherapeutic agents has led to improved life expectancy in recent years. In this article we will summarize recent therapeutic strategies depending on tumor status and current approaches to personalized medicine in pancreatic carcinoma.


Assuntos
Neoplasias Pancreáticas/terapia , Medicina de Precisão/tendências , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Previsões , Alemanha , Humanos , Estadiamento de Neoplasias , Pancreatectomia/métodos , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/patologia , Taxa de Sobrevida , Resultado do Tratamento
17.
Gastroenterology ; 154(6): 1853-1854, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29621520
18.
Gastroenterology ; 154(3): 704-718.e10, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29079517

RESUMO

BACKGROUND & AIMS: Acute pancreatitis is characterized by premature intracellular activation of digestive proteases within pancreatic acini and a consecutive systemic inflammatory response. We investigated how these processes interact during severe pancreatitis in mice. METHODS: Pancreatitis was induced in C57Bl/6 wild-type (control), cathepsin B (CTSB)-knockout, and cathepsin L-knockout mice by partial pancreatic duct ligation with supramaximal caerulein injection, or by repetitive supramaximal caerulein injections alone. Immune cells that infiltrated the pancreas were characterized by immunofluorescence detection of Ly6g, CD206, and CD68. Macrophages were isolated from bone marrow and incubated with bovine trypsinogen or isolated acinar cells; the macrophages were then transferred into pancreatitis control or cathepsin-knockout mice. Activities of proteases and nuclear factor (NF)-κB were determined using fluorogenic substrates and trypsin activity was blocked by nafamostat. Cytokine levels were measured using a cytometric bead array. We performed immunohistochemical analyses to detect trypsinogen, CD206, and CD68 in human chronic pancreatitis (n = 13) and acute necrotizing pancreatitis (n = 15) specimens. RESULTS: Macrophages were the predominant immune cell population that migrated into the pancreas during induction of pancreatitis in control mice. CD68-positive macrophages were found to phagocytose acinar cell components, including zymogen-containing vesicles, in pancreata from mice with pancreatitis, as well as human necrotic pancreatic tissues. Trypsinogen became activated in macrophages cultured with purified trypsinogen or co-cultured with pancreatic acini and in pancreata of mice with pancreatitis; trypsinogen activation required macrophage endocytosis and expression and activity of CTSB, and was sensitive to pH. Activation of trypsinogen in macrophages resulted in translocation of NF-kB and production of inflammatory cytokines; mice without trypsinogen activation (CTSB-knockout mice) in macrophages developed less severe pancreatitis compared with control mice. Transfer of macrophage from control mice to CTSB-knockout mice increased the severity of pancreatitis. Inhibition of trypsin activity in macrophages prevented translocation of NF-κB and production of inflammatory cytokines. CONCLUSIONS: Studying pancreatitis in mice, we found activation of digestive proteases to occur not only in acinar cells but also in macrophages that infiltrate pancreatic tissue. Activation of the proteases in macrophage occurs during endocytosis of zymogen-containing vesicles, and depends on pH and CTSB. This process involves macrophage activation via NF-κB-translocation, and contributes to systemic inflammation and severity of pancreatitis.


Assuntos
Catepsina B/metabolismo , Endocitose , Macrófagos/enzimologia , Pâncreas/enzimologia , Pancreatite Necrosante Aguda/enzimologia , Tripsinogênio/metabolismo , Transferência Adotiva , Animais , Catepsina B/deficiência , Catepsina B/genética , Catepsina L/deficiência , Catepsina L/genética , Células Cultivadas , Ceruletídeo , Técnicas de Cocultura , Citocinas/metabolismo , Modelos Animais de Doenças , Ativação Enzimática , Predisposição Genética para Doença , Humanos , Concentração de Íons de Hidrogênio , Mediadores da Inflamação/metabolismo , Macrófagos/imunologia , Macrófagos/patologia , Macrófagos/transplante , Camundongos Endogâmicos C57BL , Camundongos Knockout , NF-kappa B/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/deficiência , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Necrose , Pâncreas/imunologia , Pâncreas/patologia , Pancreatectomia , Pancreatite Necrosante Aguda/induzido quimicamente , Pancreatite Necrosante Aguda/imunologia , Pancreatite Necrosante Aguda/patologia , Fagocitose , Fenótipo , Índice de Gravidade de Doença , Fatores de Tempo
19.
Gut ; 67(1): 128-137, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28108468

RESUMO

OBJECTIVE: Current non-invasive diagnostic tests can distinguish between pancreatic cancer (pancreatic ductal adenocarcinoma (PDAC)) and chronic pancreatitis (CP) in only about two thirds of patients. We have searched for blood-derived metabolite biomarkers for this diagnostic purpose. DESIGN: For a case-control study in three tertiary referral centres, 914 subjects were prospectively recruited with PDAC (n=271), CP (n=282), liver cirrhosis (n=100) or healthy as well as non-pancreatic disease controls (n=261) in three consecutive studies. Metabolomic profiles of plasma and serum samples were generated from 477 metabolites identified by gas chromatography-mass spectrometry and liquid chromatography-tandem mass spectrometry. RESULTS: A biomarker signature (nine metabolites and additionally CA19-9) was identified for the differential diagnosis between PDAC and CP. The biomarker signature distinguished PDAC from CP in the training set with an area under the curve (AUC) of 0.96 (95% CI 0.93-0.98). The biomarker signature cut-off of 0.384 at 85% fixed specificity showed a sensitivity of 94.9% (95% CI 87.0%-97.0%). In the test set, an AUC of 0.94 (95% CI 0.91-0.97) and, using the same cut-off, a sensitivity of 89.9% (95% CI 81.0%-95.5%) and a specificity of 91.3% (95% CI 82.8%-96.4%) were achieved, successfully validating the biomarker signature. CONCLUSIONS: In patients with CP with an increased risk for pancreatic cancer (cumulative incidence 1.95%), the performance of this biomarker signature results in a negative predictive value of 99.9% (95% CI 99.7%-99.9%) (training set) and 99.8% (95% CI 99.6%-99.9%) (test set). In one third of our patients, the clinical use of this biomarker signature would have improved diagnosis and treatment stratification in comparison to CA19-9.


Assuntos
Biomarcadores Tumorais/sangue , Carcinoma Ductal Pancreático/diagnóstico , Detecção Precoce de Câncer/métodos , Neoplasias Pancreáticas/diagnóstico , Pancreatite Crônica/diagnóstico , Adulto , Idoso , Carcinoma Ductal Pancreático/patologia , Estudos de Casos e Controles , Diagnóstico Diferencial , Estudos de Viabilidade , Feminino , Humanos , Masculino , Metabolômica/métodos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Pancreáticas/patologia , Sensibilidade e Especificidade
20.
Gastroenterology ; 153(6): 1544-1554.e2, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28918191

RESUMO

BACKGROUND & AIMS: The clinical course of chronic pancreatitis is unpredictable. There is no model to assess disease severity or progression or predict patient outcomes. METHODS: We performed a prospective study of 91 patients with chronic pancreatitis; data were collected from patients seen at academic centers in Europe from January 2011 through April 2014. We analyzed correlations between clinical, laboratory, and imaging data with number of hospital readmissions and in-hospital days over the next 12 months; the parameters with the highest degree of correlation were used to develop a 3-stage chronic pancreatitis prognosis score (COPPS). The predictive strength was validated in 129 independent subjects identified from 2 prospective databases. RESULTS: The mean number of hospital admissions was 1.9 (95% confidence interval [CI], 1.39-2.44) and 15.2 for hospital days (95% CI, 10.76-19.71) for the development cohort and 10.9 for the validation cohort (95% CI, 7.54-14.30) (P = .08). Based on bivariate correlations, pain (numeric rating scale), level of glycated hemoglobin A1c, level of C-reactive protein, body mass index, and platelet count were used to develop the COPPS system. The patients' median COPPS was 8.9 points (range, 5-14). The system accurately discriminated stages of disease severity (low to high): A (5-6 points), B (7-9), and C (10-15). In Pearson correlation analysis of the development cohort, the COPPS correlated with hospital admissions (0.39; P < .01) and number of hospital days (0.33; P < .01). The correlation was validated in the validation set (Pearson correlation values of 0.36 and 0.44; P < .01). COPPS did not correlate with results from the Cambridge classification system. CONCLUSIONS: We developed and validated an easy to use dynamic multivariate scoring system, similar to the Child-Pugh-Score for liver cirrhosis. The COPPS allows objective monitoring of patients with chronic pancreatitis, determining risk for readmission to hospital and potential length of hospital stay.


Assuntos
Técnicas de Apoio para a Decisão , Pancreatite Crônica/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Índice de Massa Corporal , Proteína C-Reativa/análise , Distribuição de Qui-Quadrado , Progressão da Doença , Feminino , Alemanha , Hemoglobinas Glicadas/análise , Nível de Saúde , Humanos , Tempo de Internação , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Medição da Dor , Pancreatite Crônica/sangue , Pancreatite Crônica/complicações , Pancreatite Crônica/terapia , Readmissão do Paciente , Contagem de Plaquetas , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Reprodutibilidade dos Testes , Fatores de Risco , Índice de Gravidade de Doença , Fatores de Tempo , Adulto Jovem
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