50 results on '"Mahajan UM"'
Search Results
2. Chronic Pancreatitis Prognosis Score (COPPS): preliminary results from a prospective multicenter, international validation study
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Garbe, A, additional, Mahajan, UM, additional, Kohlmann, T, additional, Goni, E, additional, Budde, C, additional, Martinez-Moneo, E, additional, Shimosegawa, T, additional, Forsmark, C, additional, Garg, P, additional, Gomez, A, additional, Stigliona, S, additional, Conwell, D, additional, Lerch, MM, additional, Mayerle, J, additional, and Beyer, G, additional
- Published
- 2019
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3. Increased Cathepsin D expression has a negative prognostic effect on survival in gemcitabine treated patients with pancreatic ductal adenocarcinoma
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Mahajan, UM, additional, Goni, E, additional, Langhoff, E, additional, Kruger, S, additional, Ormanns, S, additional, Beyer, G, additional, Weiss, FU, additional, Kirchner, T, additional, Werner, J, additional, D'haese, J, additional, Bergwelt, M, additional, Heinemann, V, additional, Lerch, MM, additional, Böck, S, additional, and Mayerle, J, additional
- Published
- 2018
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4. A comprehensive prognostic signature based on interaction of immune cell infiltration with stromal composition for resected pancreatic ductal adenocarcinoma
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Mahajan, UM, additional, Langhoff, E, additional, Costello, E, additional, Greenhalf, W, additional, Holloran, C, additional, Beyer, G, additional, Weiss, FU, additional, Neoptolomos, J, additional, Büchler, MW, additional, Kohlmann, T, additional, Lerch, MM, additional, and Mayerle, J, additional
- Published
- 2017
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5. Cathepsin B and D drive the fibrogenic potential of pancreatic stellate cells and modulate the stromal compartment in pancreatic ductal adenocarcinoma (PDAC)
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Mahajan, UM, primary, Schwaiger, T, additional, Weiss, FU, additional, Löhr, M, additional, Halangk, W, additional, Lerch, MM, additional, and Mayerle, J, additional
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- 2014
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6. In vivo imaging and targeted siRNA delivery using superparamagnetic nanoparticles (MNPs) in pancreatic ductal adenocarcinoma
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Mahajan, UM, primary, Teller, S, additional, Sendler, M, additional, Schwaiger, T, additional, Partecke, LI, additional, Gloeckl, G, additional, Aurich, K, additional, Hadlich, S, additional, Weiß, FU, additional, Kühn, JP, additional, Lerch, MM, additional, and Mayerle, J, additional
- Published
- 2013
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7. Description and assessment of a neurosurgery shadowing and research program: A paradigm for early and sustained exposure to academic neurosurgery
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Duy Phan Q., Negoita Serban, Mahajan Uma V., Diab Nicholas S., Agarwal Ank A., Gupte Trisha, Paranjpe Manish D., and Anderson William S.
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neurosurgery ,medical education ,pre-medicine ,shadowing ,research ,surgical education ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
To describe and assess the educational value of a functional neurosurgery clinical shadowing and research tutorial for pre-medical trainees.
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- 2019
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8. ROR2 Regulates Cellular Plasticity in Pancreatic Neoplasia and Adenocarcinoma.
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Benitz S, Steep A, Nasser MM, Preall J, Mahajan UM, McQuithey H, Loveless I, Davis ET, Wen HJ, Long DW, Metzler T, Zwernik S, Louw M, Rempinski D, Salas-Escabillas DJ, Brender SM, Song L, Huang L, Theisen BK, Zhang Z, Steele NG, Regel I, Bednar F, and Crawford HC
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- Animals, Humans, Mice, Carcinoma, Pancreatic Ductal pathology, Carcinoma, Pancreatic Ductal genetics, Carcinoma, Pancreatic Ductal metabolism, Adenocarcinoma pathology, Adenocarcinoma genetics, Adenocarcinoma metabolism, Epithelial-Mesenchymal Transition, Cell Line, Tumor, Receptor Tyrosine Kinase-like Orphan Receptors metabolism, Receptor Tyrosine Kinase-like Orphan Receptors genetics, Pancreatic Neoplasms pathology, Pancreatic Neoplasms genetics, Pancreatic Neoplasms metabolism, Cell Plasticity
- Abstract
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 a mouse and human. We identified the receptor tyrosine kinase ROR2 as marker of a gastric metaplasia-like identity in pancreas neoplasms. 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. Significance: We discovered the receptor tyrosine kinase ROR2 as an important regulator of cellular identity in pancreatic precancerous lesions and pancreatic cancer. ROR2 drives an aggressive PDAC phenotype and confers resistance to KRAS inhibitors, suggesting that targeting ROR2 will enhance sensitivity to this new generation of targeted therapies. See related commentary by Marasco and Misale, p. 2018., (©2024 The Authors; Published by the American Association for Cancer Research.)
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- 2024
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9. Severity of Gallstone-, Sludge-, or Microlithiasis-Induced Pancreatitis-All of the Same?
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Sirtl S, Bretthauer K, Ahmad M, Hohmann E, Schmidt VF, Allawadhi P, Vornhülz M, Klauss S, Goni E, Vielhauer J, Orgler E, Saka D, Knoblauch M, Hofmann FO, Schirra J, Schulz C, Beyer G, Mahajan UM, Mayerle J, and Zorniak M
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- Humans, Retrospective Studies, Male, Middle Aged, Female, Aged, Adult, Endosonography methods, Lithiasis complications, Gallstones complications, Gallstones diagnostic imaging, Pancreatitis etiology, Pancreatitis complications, Pancreatitis diagnosis, Severity of Illness Index, Cholangiopancreatography, Endoscopic Retrograde
- Abstract
Background/aim: Severity of microlithiasis- and sludge-induced pancreatitis in comparison to gallstone-induced pancreatitis has never been studied for a lack of definition., Materials and Methods: In this retrospective cohort study, 263 patients with acute biliary pancreatitis treated at a tertiary care center from 2005 to 2021 were stratified according to the recent consensus definition for microlithiasis and sludge. The gallstone-pancreatitis cohort was compared to microlithiasis, sludge, and suspected stone passage pancreatitis cohorts in terms of pancreatitis outcome, liver function, and endosonography/endoscopic retrograde cholangiopancreatography results using one-way analysis of variance and χ 2 test. Multinomial logistic regression analysis was performed to correct for bias., Results: Microlithiasis- and sludge-induced pancreatitis, classified according to the revised Atlanta classification, did not present with a milder course than gallstone-induced pancreatitis ( P = 0.62). Microlithiasis and sludge showed an increase in bilirubin on the day of admission to hospital, which was not significantly different from gallstone-induced pancreatitis ( P = 0.36). The likelihood of detecting biliary disease on endosonography resulting in bile duct clearance was highest on the day of admission and day 1, respectively., Conclusions: Microlithiasis and sludge induce gallstone-equivalent impaired liver function tests and induce pancreatitis with similar severity compared with gallstone-induced acute biliary pancreatitis., Competing Interests: The authors declare no conflict of interest., (Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc.)
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- 2024
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10. Severity and outcome of a first episode of idiopathic acute pancreatitis is not more severe than pancreatitis of other etiologies.
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Sirtl S, Hohmann E, Ahmad M, Bretthauer K, Junge M, Vornhülz M, Goni E, Saka D, Knoblauch M, Aghamaliyev U, Schulz C, Zorniak M, Mahajan UM, Mayerle J, and Beyer G
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- Humans, Male, Female, Retrospective Studies, Middle Aged, Aged, Adult, Pancreatitis, Alcoholic complications, Cohort Studies, Acute Disease, Recurrence, Patient Readmission, Treatment Outcome, Pancreatitis complications, Pancreatitis mortality, Pancreatitis etiology, Severity of Illness Index
- Abstract
Background: With respect to severity and outcome of an index episode of idiopathic acute pancreatitis the current literature reports conflicting retrospective results. One reason might be the retrospective study design precluding in depth analysis resulting in mixed etiologies and combination of index episode versus recurrent idiopathic acute pancreatitis., Methods: In this retrospective monocentric cohort study, we retrieved all patients with a first acute pancreatitis episode treated between 2005 and 2021 at the LMU University Hospital from our clinical information system based on the respective ICD-10 codes. In an initial sample of 1390 presumed idiopathic pancreatitis patients we identified 68 confirmed idiopathic acute pancreatitis patients and compared those to 75 first-time alcohol-induced acute pancreatitis patients and 390 first-time biliary-induced acute pancreatitis patients. Clinical outcome (severity, SIRS, mortality, and re-admission rate) was set as outcome measures. Multinomial logistic regression analysis was performed., Results: In alcohol-induced acute pancreatitis moderate and severe courses occur significantly more often when compared to idiopathic acute pancreatitis (17.33 % vs. 10.29 %; multinomial logistic regression p = 0.0021). There were no significant differences in mortality between first-time alcoholic, idiopathic and biliary pancreatitis (p = 0.6328). Patients with idiopathic acute pancreatitis had significantly more hospital readmissions (within 30 days) compared to alcohol-induced pancreatitis patients (p = 0.0284)., Conclusion: In the context of a first episode of acute pancreatitis, idiopathic acute pancreatitis remains a challenging diagnosis posing an increased risk of recurrence, but not an increased risk for a more severe disease course., Competing Interests: Declaration of competing interest The authors declare no potential conflicts of interest concerning the research, authorship, and/or publication of this article., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)
- Published
- 2024
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11. Electronic data capture in resource-limited settings using the lightweight clinical data acquisition and recording system.
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Vielhauer J, Mahajan UM, Adorjan K, Benesch C, Oehrle B, Beyer G, Sirtl S, Johlke AL, Allgeier J, Pernpruner A, Erber J, Shamsrizi P, Schulz C, Albashiti F, Hinske LC, Mayerle J, and Stubbe HC
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- Humans, Mobile Applications, User-Computer Interface, Electronic Health Records, Databases, Factual, Data Collection methods, Resource-Limited Settings, Software
- Abstract
Our prototype system designed for clinical data acquisition and recording of studies is a novel electronic data capture (EDC) software for simple and lightweight data capture in clinical research. Existing software tools are either costly or suffer from very limited features. To overcome these shortcomings, we designed an EDC software together with a mobile client. We aimed at making it easy to set-up, modifiable, scalable and thereby facilitating research. We wrote the software in R using a modular approach and implemented existing data standards along with a meta data driven interface and database structure. The prototype is an adaptable open-source software, which can be installed locally or in the cloud without advanced IT-knowledge. A mobile web interface and progressive web app for mobile use and desktop computers is added. We show the software's capability, by demonstrating four clinical studies with over 1600 participants and 679 variables per participant. We delineate a simple deployment approach for a server-installation and indicate further use-cases. The software is available under the MIT open-source license. Conclusively the software is versatile, easily deployable, highly modifiable, and extremely scalable for clinical studies. As an open-source R-software it is accessible, open to community-driven development and improvement in the future., (© 2024. The Author(s).)
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- 2024
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12. Altered histone acetylation patterns in pancreatic cancer cell lines induce subtype‑specific transcriptomic and phenotypical changes.
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Zhou Q, Pichlmeier S, Denz AM, Schreiner N, Straub T, Benitz S, Wolff J, Fahr L, Del Socorro Escobar Lopez M, Kleeff J, Mayerle J, Mahajan UM, and Regel I
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- Humans, Histones genetics, Histones metabolism, Gemcitabine, Epigenesis, Genetic, Acetylation, Cell Line, Tumor, Histone Deacetylase Inhibitors pharmacology, Histone Deacetylase Inhibitors therapeutic use, Gene Expression Profiling, Gene Expression Regulation, Neoplastic, Pancreatic Neoplasms drug therapy, Pancreatic Neoplasms genetics, Pancreatic Neoplasms metabolism, Carcinoma, Pancreatic Ductal drug therapy, Carcinoma, Pancreatic Ductal genetics, Carcinoma, Pancreatic Ductal metabolism
- Abstract
Pancreatic ductal adenocarcinoma (PDAC) is often diagnosed at advanced tumor stages with chemotherapy as the only treatment option. Transcriptomic analysis has defined a classical and basal‑like PDAC subtype, which are regulated by epigenetic modification. The present study aimed to determine if drug‑induced epigenetic reprogramming of pancreatic cancer cells affects PDAC subtype identity and chemosensitivity. Classical and basal‑like PDAC cell lines PaTu‑S, Capan‑1, Capan‑2, Colo357, PaTu‑T, PANC‑1 and MIAPaCa‑2, were treated for a short (up to 96 h) and long (up to 30 weeks) period with histone acetyltransferase (HAT) and histone deacetylase (HDAC) inhibitors. The cells were analyzed using gene expression approaches, immunoblot analysis, and various cell assays to assess cell characteristics, such as proliferation, colony formation, cell migration and sensitivity to chemotherapeutic drugs. Classical and basal‑like PDAC cell lines showed pronounced epigenetic regulation of subtype‑specific genes through acetylation of lysine 27 on Histone H3 (H3K27ac). Moreover, classical cell lines revealed a significantly decreased expression of HDAC2 and increased total levels of H3K27ac in comparison with the basal‑like cell lines. Following HAT inhibitor treatment, classical cell lines exhibited a loss of epithelial marker gene expression, decreased chemotherapy response gene score and increased cell migration in vitro , indicating a tumor‑promoting phenotype. HDAC inhibitor treatment, however, exerted minimal reprogramming effects in both subtypes. Epigenetic reprogramming of classical and basal‑like tumor cells did not have a major impact on gemcitabine response, although the gemcitabine transporter gene SLC29A1 (solute carrier family 29 member 1) was epigenetically regulated.
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- 2024
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13. The inhibition of YAP Signaling Prevents Chronic Biliary Fibrosis in the Abcb4 -/- Model by Modulation of Hepatic Stellate Cell and Bile Duct Epithelium Cell Pathophysiology.
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Ye L, Ziesch A, Schneider JS, Ofner A, Nieß H, Denk G, Hohenester S, Mayr D, Mahajan UM, Munker S, Khaled NB, Wimmer R, Gerbes AL, Mayerle J, He Y, Geier A, Toni EN, Zhang C, and Reiter FP
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- Mice, Animals, Humans, Liver Cirrhosis drug therapy, Fibrosis, Bile Ducts, Epithelium metabolism, Hepatic Stellate Cells, Cholestasis metabolism
- Abstract
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.- Published
- 2024
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14. Validation of the SACOV-19 score for identifying patients at risk of complicated or more severe COVID-19: a prospective study.
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Mahajan UM, Erber J, Shamsrizi P, Voit F, Vielhauer J, Johlke AL, Benesch C, Khaled NB, Reinecke F, Rudi WS, Klein M, Jakob C, Oswald M, König R, Schulz C, Mayerle J, and Stubbe HC
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- Adult, Humans, Prospective Studies, SARS-CoV-2, Hospitalization, Hospitals, COVID-19 diagnosis
- Abstract
Purpose: Identification of patients at risk of complicated or more severe COVID-19 is of pivotal importance, since these patients might require monitoring, antiviral treatment, and hospitalization. In this study, we prospectively evaluated the SACOV-19 score for its ability to predict complicated or more severe COVID-19., Methods: In this prospective multicenter study, we included 124 adult patients with acute COVID-19 in three German hospitals, who were diagnosed in an early, uncomplicated stage of COVID-19 within 72 h of inclusion. We determined the SACOV-19 score at baseline and performed a follow-up at 30 days., Results: The SACOV-19 score's AUC was 0.816. At a cutoff of > 3, it predicted deterioration to complicated or more severe COVID-19 with a sensitivity of 94% and a specificity of 55%. It performed significantly better in predicting complicated COVID-19 than the random tree-based SACOV-19 predictive model, the CURB-65, 4C mortality, or qCSI scores., Conclusion: The SACOV-19 score is a feasible tool to aid decision making in acute COVID-19., (© 2023. The Author(s).)
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- 2023
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15. Consensus definition of sludge and microlithiasis as a possible cause of pancreatitis.
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Żorniak M, Sirtl S, Beyer G, Mahajan UM, Bretthauer K, Schirra J, Schulz C, Kohlmann T, Lerch MM, and Mayerle J
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- Humans, Retrospective Studies, Prospective Studies, Acute Disease, Consensus, Pancreatitis complications, Pancreatitis diagnostic imaging, Gallstones complications
- Abstract
Objective: In up to 20% of patients, the aetiology of acute pancreatitis (AP) remains elusive and is thus called idiopathic. On more detailed review these cases can often be explained through biliary disease and are amenable to treatment. Findings range from biliary sludge to microlithiasis but their definitions remain fluid and controversial., Design: A systematic literature review (1682 reports, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines) analysed definitions of biliary sludge and microlithiasis, followed by an online international expert survey (30 endoscopic ultrasound/hepatobiliary and pancreatic experts; 36 items) which led to definitions of both. These were consented by Delphi voting and clinically evaluated in a retrospective cohort of patients with presumed biliary pancreatitis., Results: In 13% of original articles and 19.2% of reviews, microlithiasis and biliary sludge were used synonymously. In the survey, 41.7% of experts described the term 'sludge' and 'microlithiasis' as identical findings. As a consequence, three definitions were proposed, agreed on and confirmed by voting to distinctly discriminate between biliary sludge (hyperechoic material without acoustic shadowing) and microlithiasis (echorich calculi of ≤5 mm with acoustic shadowing) as opposed to larger biliary stones, both for location in gallbladder and bile ducts. In an initial attempt to investigate the clinical relevance in a retrospective analysis in 177 confirmed cases in our hospital, there was no difference in severity of AP if caused by sludge, microlithiasis or stones., Conclusion: We propose a consensus definition for the localisation, ultrasound morphology and diameter of biliary sludge and microlithiasis as distinct entities. Interestingly, severity of biliary AP was not dependent on the size of concrements warranting prospective randomised studies which treatment options are adequate to prevent recurrence., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)
- Published
- 2023
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16. Machine learning-based decision tool for selecting patients with idiopathic acute pancreatitis for endosonography to exclude a biliary aetiology.
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Sirtl S, Żorniak M, Hohmann E, Beyer G, Dibos M, Wandel A, Phillip V, Ammer-Herrmenau C, Neesse A, Schulz C, Schirra J, Mayerle J, and Mahajan UM
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- Humans, Retrospective Studies, Acute Disease, Patient Selection, Sewage, Machine Learning, Endosonography, Pancreatitis, Chronic
- Abstract
Background: Biliary microlithiasis/sludge is detected in approximately 30% of patients with idiopathic acute pancreatitis (IAP). As recurrent biliary pancreatitis can be prevented, the underlying aetiology of IAP should be established., Aim: To develop a machine learning (ML) based decision tool for the use of endosonography (EUS) in pancreatitis patients to detect sludge and microlithiasis., Methods: We retrospectively used routinely recorded clinical and laboratory parameters of 218 consecutive patients with confirmed AP admitted to our tertiary care hospital between 2015 and 2020. Patients who did not receive EUS as part of the diagnostic work-up and whose pancreatitis episode could be adequately explained by other causes than biliary sludge and microlithiasis were excluded. We trained supervised ML classifiers using H
2 O.ai automatically selecting the best suitable predictor model to predict microlithiasis/sludge. The predictor model was further validated in two independent retrospective cohorts from two tertiary care centers (117 patients)., Results: Twenty-eight categorized patients' variables recorded at admission were identified to compute the predictor model with an accuracy of 0.84 [95% confidence interval (CI): 0.791-0.9185], positive predictive value of 0.84, and negative predictive value of 0.80 in the identification cohort (218 patients). In the validation cohort, the robustness of the prediction model was confirmed with an accuracy of 0.76 (95%CI: 0.673-0.8347), positive predictive value of 0.76, and negative predictive value of 0.78 (117 patients)., Conclusion: We present a robust and validated ML-based predictor model consisting of routinely recorded parameters at admission that can predict biliary sludge and microlithiasis as the cause of AP., Competing Interests: Conflict-of-interest statement: All the authors report no relevant conflicts of interest for this article., (©The Author(s) 2023. Published by Baishideng Publishing Group Inc. All rights reserved.)- Published
- 2023
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17. How to exclude pulmonary embolism in patients hospitalized with COVID-19: a comparison of predictive scores.
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Vielhauer J, Benesch C, Pernpruner A, Johlke AL, Hellmuth JC, Muenchhoff M, Scherer C, Fink N, Sabel B, Schulz C, Mayerle J, Mahajan UM, and Stubbe HC
- Abstract
Background: Pulmonary embolism (PE) is an important complication of Coronavirus disease 2019 (COVID-19). COVID-19 is associated with respiratory impairment and a pro-coagulative state, rendering PE more likely and difficult to recognize. Several decision algorithms relying on clinical features and D-dimer have been established. High prevalence of PE and elevated Ddimer in patients with COVID-19 might impair the performance of common decision algorithms. Here, we aimed to validate and compare five common decision algorithms implementing age adjusted Ddimer, the GENEVA, and Wells scores as well as the PEGeD- and YEARS-algorithms in patients hospitalized with COVID-19., Methods: In this single center study, we included patients who were admitted to our tertiary care hospital in the COVID-19 Registry of the LMU Munich. We retrospectively selected patients who received a computed tomography pulmonary angiogram (CTPA) or pulmonary ventilation/perfusion scintigraphy (V/Q) for suspected PE. The performances of five commonly used diagnostic algorithms (age-adjusted D-dimer, GENEVA score, PEGeD-algorithm, Wells score, and YEARS-algorithm) were compared., Results: We identified 413 patients with suspected PE who received a CTPA or V/Q confirming 62 PEs (15%). Among them, 358 patients with 48 PEs (13%) could be evaluated for performance of all algorithms. Patients with PE were older and their overall outcome was worse compared to patients without PE. Of the above five diagnostic algorithms, the PEGeD- and YEARS-algorithms performed best, reducing diagnostic imaging by 14% and 15% respectively with a sensitivity of 95.7% and 95.6%. The GENEVA score was able to reduce CTPA or V/Q by 32.2% but suffered from a low sensitivity (78.6%). Age-adjusted D-dimer and Wells score could not significantly reduce diagnostic imaging., Conclusion: The PEGeD- and YEARS-algorithms outperformed other tested decision algorithms and worked well in patients admitted with COVID-19. These findings need independent validation in a prospective study., (© 2023. The Author(s).)
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- 2023
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18. Independent Validation and Assay Standardization of Improved Metabolic Biomarker Signature to Differentiate Pancreatic Ductal Adenocarcinoma From Chronic Pancreatitis.
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Mahajan UM, Oehrle B, Sirtl S, Alnatsha A, Goni E, Regel I, Beyer G, Vornhülz M, Vielhauer J, Chromik A, Bahra M, Klein F, Uhl W, Fahlbusch T, Distler M, Weitz J, Grützmann R, Pilarsky C, Weiss FU, Adam MG, Neoptolemos JP, Kalthoff H, Rad R, Christiansen N, Bethan B, Kamlage B, Lerch MM, and Mayerle J
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- Humans, CA-19-9 Antigen, Biomarkers, Tumor, ROC Curve, Case-Control Studies, Reference Standards, Carbohydrates, Pancreatic Neoplasms, Carcinoma, Pancreatic Ductal pathology, Pancreatic Neoplasms pathology, Pancreatitis, Chronic diagnosis
- Abstract
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., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)
- Published
- 2022
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19. TRAIL Receptor Targeting Agents Potentiate PARP Inhibitor Efficacy in Pancreatic Cancer Independently of BRCA2 Mutation Status.
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Ben Khaled N, Hammer K, Ye L, Alnatsha A, Widholz SA, Piseddu I, Sirtl S, Schneider J, Munker S, Mahajan UM, Montero JJ, Griger J, Mayerle J, Reiter FP, and De Toni EN
- Abstract
Chemotherapy, the standard treatment for pancreatic ductal adenocarcinoma (PDAC), has only a modest effect on the outcome of patients with late-stage disease. Investigations of the genetic features of PDAC have demonstrated a frequent occurrence of mutations in genes involved in homologous recombination (HR), especially in the breast cancer susceptibility gene 2 ( BRCA2 ). Olaparib, a poly(ADP-ribose) polymerase (PARP) inhibitor, is approved as a maintenance treatment for patients with advanced PDAC with germline BRCA1/2 mutations following a platinum-containing first-line regimen. Limitations to the use of PARP inhibitors are represented by the relatively small proportion of patients with mutations in BRCA1/2 genes and the modest capability of these substances of inducing objective response. We have previously shown that pancreatic cancer with BRCA2 mutations exhibits a remarkably enhanced sensitivity towards tumor-necrosis-factor-related apoptosis-inducing ligand (TRAIL) receptor-stimulating agents. We thus aimed to investigate the effect of combined treatment with PARP inhibitors and TRAIL receptor-stimulating agents in pancreatic cancer and its dependency on the BRCA2 gene status. The respective effects of TRAIL-targeting agents and the PARP inhibitor olaparib or of their combination were assessed in pancreatic cancer cell lines and patient-derived organoids. In addition, BRCA2 -knockout and -complementation models were investigated. The effects of these agents on apoptosis, DNA damage, cell cycle, and receptor surface expression were assessed by immunofluorescence, Western blot, and flow cytometry. PARP inhibition and TRAIL synergized to cause cell death in pancreatic cancer cell lines and PDAC organoids. This effect proved independent of BRCA2 gene status in three independent models. Olaparib and TRAIL in combination caused a detectable increase in DNA damage and a concentration-dependent cell cycle arrest in the G2/M and S cell cycle phases. Olaparib also significantly increased the proportion of membrane-bound death receptor 5. Our results provide a preclinical rationale for the combination of PARP inhibitors and TRAIL receptor agonists for the treatment of pancreatic cancer and suggest that the use of PARP inhibitors could be extended to patients without BRCA2 mutations if used in combination with TRAIL agonists.
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- 2022
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20. The influence of gastric atrophy on Helicobacter pylori antibiotics resistance in therapy-naïve patients.
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Goni E, Tammer I, Schütte K, Thon C, Jechorek D, Mahajan UM, Vasapolli R, Macke L, Aulinger B, Selgrad M, Link A, Malfertheiner P, and Schulz C
- Abstract
Background: Antibiotic susceptibility of Helicobacter pylori to antibiotics may vary among different niches of the stomach. The progression of chronic H. pylori gastritis to atrophy changes intragastric physiology that may influence selection of resistant strains., Aim: To study the antibiotic resistance of H. pylori taking the severity of atrophic gastritis in antrum and corpus into account., Methods: Helicobacter pylori -positive patients ( n = 110, m = 32, mean age 52.6 ± 13.9 years) without prior H. pylori eradication undergoing upper gastrointestinal (GI) endoscopy for dyspeptic symptoms were included in a prospective study. Patients were stratified into three groups depending on the grade of atrophy: no atrophy (OLGA Stage 0), mild atrophy (OLGA Stage I-II) and moderate/severe atrophy (OLGA Stage III-IV). Two biopsies each from the antrum and the corpus and one from the angulus were taken and assessed according to the updated Sydney system. H. pylori strains were isolated from antrum and corpus biopsies and tested for antibiotic susceptibility (AST) for amoxicillin, clarithromycin, metronidazole, levofloxacin, tetracycline, and rifampicin by the agar dilution methods. A Chi-square test of independence with a 95% confidence interval was used to detect differences in the proportion of patients with susceptible and resistant H. pylori strains., Results: Among 110 patients, primary clarithromycin resistance (R) was 30.0%, both in the antrum and corpus; metronidazole resistance accounted for 36.4 and 34.5% in the antrum and corpus; and levofloxacin was 19.1 and 22.7% in the antrum and corpus, respectively. Resistance rates to amoxicillin, tetracycline, and rifampicin were below 5%. Dual antibiotic resistance rate was 21.8%, and triple resistance rate was 9.1%. There was a significant difference in the resistance rate distribution in antrum ( p < 0.0001) and corpus ( p < 0.0001). With increasing severity of atrophy according to OLGA stages, there was a significant increase in clarithromycin-R and metronidazole-R., Conclusion: In treatment-naïve patients, antibiotic resistance and heteroresistance were related to the severity of atrophy. The high clarithromycin resistance in atrophic gastritis suggests that H. pylori antibiotic susceptibility testing should always be performed in this condition before selecting the eradication regimen., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Goni, Tammer, Schütte, Thon, Jechorek, Mahajan, Vasapolli, Macke, Aulinger, Selgrad, Link, Malfertheiner and Schulz.)
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- 2022
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21. Impact of tumor size and location on endoscopic ultrasound-guided sampling of pancreatic neuroendocrine tumors: A recursive partitioning analysis.
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Sirtl S, Mahajan UM, Auernhammer CJ, Dziadkiewicz P, Hohmann E, Wójcik M, Kos-Kudła B, Hartleb M, Knösel T, Schirra J, Mayerle J, Schulz C, and Żorniak M
- Subjects
- Endoscopic Ultrasound-Guided Fine Needle Aspiration, Humans, Retrospective Studies, Neuroectodermal Tumors, Primitive, Neuroendocrine Tumors pathology, Pancreatic Neoplasms pathology
- Abstract
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., Competing Interests: Declaration of competing interest The authors declare no potential conflicts of interest concerning the research, authorship, and/or publication of this article., (Copyright © 2022 IAP and EPC. Published by Elsevier B.V. All rights reserved.)
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- 2022
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22. Epigenetic drug screening defines a PRMT5 inhibitor-sensitive pancreatic cancer subtype.
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Orben F, Lankes K, Schneeweis C, Hassan Z, Jakubowsky H, Krauß L, Boniolo F, Schneider C, Schäfer A, Murr J, Schlag C, Kong B, Öllinger R, Wang C, Beyer G, Mahajan UM, Xue Y, Mayerle J, Schmid RM, Kuster B, Rad R, Braun CJ, Wirth M, Reichert M, Saur D, and Schneider G
- Subjects
- Animals, Cell Line, Tumor, Drug Evaluation, Preclinical, Early Detection of Cancer, Enzyme Inhibitors pharmacology, Enzyme Inhibitors therapeutic use, Epigenesis, Genetic, Humans, Mice, Protein-Arginine N-Methyltransferases genetics, Proto-Oncogene Proteins c-myc genetics, Proto-Oncogene Proteins c-myc metabolism, Pancreatic Neoplasms, Carcinoma, Pancreatic Ductal drug therapy, Carcinoma, Pancreatic Ductal genetics, Carcinoma, Pancreatic Ductal pathology, Pancreatic Neoplasms drug therapy, Pancreatic Neoplasms genetics, Pancreatic Neoplasms metabolism
- Abstract
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.
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- 2022
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23. HLA-DRB1∗16 and -DQB1∗05 alleles are strongly associated with autoimmune pancreatitis in a cohort of hundred patients.
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Goni E, Regel I, Mahajan UM, Amodio A, De Marchi G, Beyer G, Zuppardo RA, Di Leo M, Lanzillotta M, Bonatti F, Kauke T, Dick A, Weiss FU, Schönermarck U, Lerch MM, Frulloni L, Cavestro GM, and Mayerle J
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- Alleles, Gene Frequency, Genetic Predisposition to Disease, HLA-DRB1 Chains genetics, HLA-DRB4 Chains genetics, Haplotypes, Humans, Autoimmune Pancreatitis
- Abstract
Background/objectives: Autoimmune diseases are often associated with human leukocyte antigen (HLA) haplotypes, indicating that changes in major histocompatibility complex (MHC)-dependent self-peptide or antigen presentation contribute to autoimmunity. In our study, we aimed to investigate HLA alleles in a large European cohort of autoimmune pancreatitis (AIP) patients., Methods: Hundred patients with AIP, diagnosed and classified according to the International Consensus Diagnostic Criteria (ICDC), were prospectively enrolled in the study. Forty-four patients with chronic pancreatitis (CP) and 254 healthy subjects served as control groups. DNA was isolated from blood samples and two-digit HLA typing was performed with sequence-specific primer (SSP-) PCR. HLA allele association strength to AIP was calculated as odds ratio., Results: We uncovered a strong enrichment of HLA-DQB1 homozygosity in type 1 and type 2 AIP patients. Moreover, a significantly increased incidence of the HLA-DRB1∗16 and HLA-DQB1∗05 alleles and a concomitant lack of the HLA-DRB1∗13 allele was detected in AIP type 1 and type 2 patients. In contrast, the HLA-DQB1∗02 allele was underrepresented in the 'not otherwise specified' (NOS) AIP subtype. We detected no significant difference in the HLA-DRB3, HLA-DRB4 and HLA-DRB5 allele frequency in our cohort., Conclusions: Although AIP type 1 and type 2 are characterized by distinct histopathological characteristics, both subtypes are associated with the same HLA alleles, indicating that the disease might rely on similar immunogenic mechanisms. However, AIP NOS represented another subclass of AIP., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)
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- 2022
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24. Prediction of COVID-19 deterioration in high-risk patients at diagnosis: an early warning score for advanced COVID-19 developed by machine learning.
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Jakob CEM, Mahajan UM, Oswald M, Stecher M, Schons M, Mayerle J, Rieg S, Pletz M, Merle U, Wille K, Borgmann S, Spinner CD, Dolff S, Scherer C, Pilgram L, Rüthrich M, Hanses F, Hower M, Strauß R, Massberg S, Er AG, Jung N, Vehreschild JJ, Stubbe H, Tometten L, and König R
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- Area Under Curve, Humans, Machine Learning, Retrospective Studies, SARS-CoV-2, COVID-19 diagnosis, Early Warning Score
- Abstract
Purpose: While more advanced COVID-19 necessitates medical interventions and hospitalization, patients with mild COVID-19 do not require this. Identifying patients at risk of progressing to advanced COVID-19 might guide treatment decisions, particularly for better prioritizing patients in need for hospitalization., Methods: We developed a machine learning-based predictor for deriving a clinical score identifying patients with asymptomatic/mild COVID-19 at risk of progressing to advanced COVID-19. Clinical data from SARS-CoV-2 positive patients from the multicenter Lean European Open Survey on SARS-CoV-2 Infected Patients (LEOSS) were used for discovery (2020-03-16 to 2020-07-14) and validation (data from 2020-07-15 to 2021-02-16)., Results: The LEOSS dataset contains 473 baseline patient parameters measured at the first patient contact. After training the predictor model on a training dataset comprising 1233 patients, 20 of the 473 parameters were selected for the predictor model. From the predictor model, we delineated a composite predictive score (SACOV-19, Score for the prediction of an Advanced stage of COVID-19) with eleven variables. In the validation cohort (n = 2264 patients), we observed good prediction performance with an area under the curve (AUC) of 0.73 ± 0.01. Besides temperature, age, body mass index and smoking habit, variables indicating pulmonary involvement (respiration rate, oxygen saturation, dyspnea), inflammation (CRP, LDH, lymphocyte counts), and acute kidney injury at diagnosis were identified. For better interpretability, the predictor was translated into a web interface., Conclusion: We present a machine learning-based predictor model and a clinical score for identifying patients at risk of developing advanced COVID-19., (© 2021. The Author(s).)
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- 2022
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25. Novel Insights Into Macrophage Diversity During the Course of Pancreatitis.
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Allawadhi P, Beyer G, Mahajan UM, and Mayerle J
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- Humans, Macrophages, Pancreatitis
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- 2021
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26. Identification and validation of a multivariable prediction model based on blood plasma and serum metabolomics for the distinction of chronic pancreatitis subjects from non-pancreas disease control subjects.
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Adam MG, Beyer G, Christiansen N, Kamlage B, Pilarsky C, Distler M, Fahlbusch T, Chromik A, Klein F, Bahra M, Uhl W, Grützmann R, Mahajan UM, Weiss FU, Mayerle J, and Lerch MM
- Subjects
- Bayes Theorem, Biomarkers blood, Case-Control Studies, Chromatography, Gas, Chromatography, Liquid, Female, Humans, Male, Mass Spectrometry, Predictive Value of Tests, Prognosis, Proof of Concept Study, Metabolomics, Pancreatitis, Chronic blood, Plasma
- Abstract
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., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2021. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)
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- 2021
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27. Tumor-Specific Delivery of 5-Fluorouracil-Incorporated Epidermal Growth Factor Receptor-Targeted Aptamers as an Efficient Treatment in Pancreatic Ductal Adenocarcinoma Models.
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Mahajan UM, Li Q, Alnatsha A, Maas J, Orth M, Maier SH, Peterhansl J, Regel I, Sendler M, Wagh PR, Mishra N, Xue Y, Allawadhi P, Beyer G, Kühn JP, Marshall T, Appel B, Lämmerhirt F, Belka C, Müller S, Weiss FU, Lauber K, Lerch MM, and Mayerle J
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- Animals, Antimetabolites, Antineoplastic metabolism, Aptamers, Nucleotide metabolism, Carcinoma, Pancreatic Ductal metabolism, Carcinoma, Pancreatic Ductal pathology, Cell Line, Tumor, Cell Proliferation drug effects, Drug Resistance, Neoplasm, Endocytosis, ErbB Receptors genetics, Female, Fluorouracil metabolism, Humans, Male, Mice, Inbred C57BL, Mice, Transgenic, Organoids, Pancreatic Neoplasms genetics, Pancreatic Neoplasms metabolism, Pancreatic Neoplasms pathology, SELEX Aptamer Technique, Tumor Burden drug effects, Tumor Cells, Cultured, Xenograft Model Antitumor Assays, Mice, Antimetabolites, Antineoplastic administration & dosage, Aptamers, Nucleotide administration & dosage, Carcinoma, Pancreatic Ductal drug therapy, Drug Delivery Systems, ErbB Receptors metabolism, Fluorouracil administration & dosage, Pancreatic Neoplasms drug therapy
- Abstract
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-Kras
G12D/+ ;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., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)- Published
- 2021
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28. Plasma Metabolome Profiling Identifies Metabolic Subtypes of Pancreatic Ductal Adenocarcinoma.
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Mahajan UM, Alnatsha A, Li Q, Oehrle B, Weiss FU, Sendler M, Distler M, Uhl W, Fahlbusch T, Goni E, Beyer G, Chromik A, Bahra M, Klein F, Pilarsky C, Grützmann R, Lerch MM, Lauber K, Christiansen N, Kamlage B, Regel I, and Mayerle J
- Subjects
- Cohort Studies, Fatty Acids metabolism, Humans, Lipid Metabolism, Sphingolipids metabolism, Transcriptome genetics, Pancreatic Neoplasms, Adenocarcinoma blood, Carcinoma, Pancreatic Ductal blood, Metabolome, Metabolomics, Pancreatic Neoplasms blood
- Abstract
Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest cancers. Developing biomarkers for early detection and chemotherapeutic response prediction is crucial to improve the dismal prognosis of PDAC patients. However, molecular cancer signatures based on transcriptome analysis do not reflect intratumoral heterogeneity. To explore a more accurate stratification of PDAC phenotypes in an easily accessible matrix, plasma metabolome analysis using MxP
® Global Profiling and MxP® Lipidomics was performed in 361 PDAC patients. We identified three metabolic PDAC subtypes associated with distinct complex lipid patterns. Subtype 1 was associated with reduced ceramide levels and a strong enrichment of triacylglycerols. Subtype 2 demonstrated increased abundance of ceramides, sphingomyelin and other complex sphingolipids, whereas subtype 3 showed decreased levels of sphingolipid metabolites in plasma. Pathway enrichment analysis revealed that sphingolipid-related pathways differ most among subtypes. Weighted correlation network analysis (WGCNA) implied PDAC subtypes differed in their metabolic programs. Interestingly, a reduced expression among related pathway genes in tumor tissue was associated with the lowest survival rate. However, our metabolic PDAC subtypes did not show any correlation to the described molecular PDAC subtypes. Our findings pave the way for further studies investigating sphingolipids metabolisms in PDAC.- Published
- 2021
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29. Pancreatitis severity in mice with impaired CFTR function but pancreatic sufficiency is mediated via ductal and inflammatory cells-Not acinar cells.
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Trapp S, Aghdassi AA, Glaubitz J, Sendler M, Weiss FU, Kühn JP, Kromrey ML, Mahajan UM, Pallagi P, Rakonczay Z Jr, Venglovecz V, Lerch MM, Hegyi P, and Mayerle J
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- Acinar Cells metabolism, Animals, Chlorides metabolism, Cystic Fibrosis Transmembrane Conductance Regulator metabolism, Humans, Inflammation etiology, Inflammation metabolism, Male, Mice, Mice, Transgenic, Pancreatic Ducts metabolism, Pancreatitis etiology, Pancreatitis metabolism, Severity of Illness Index, Acinar Cells cytology, Cystic Fibrosis complications, Cystic Fibrosis Transmembrane Conductance Regulator genetics, Inflammation pathology, Mutation, Pancreatic Ducts pathology, Pancreatitis pathology
- Abstract
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 (CFTR
tm1HGU ) 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., (© 2021 The Authors. Journal of Cellular and Molecular Medicine published by Foundation for Cellular and Molecular Medicine and John Wiley & Sons Ltd.)- Published
- 2021
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30. Influence of COVID-19 Pandemic on Endoscopic Procedures in Two European Large-Capacity Endoscopy Units: "Keep Calm, Keep Safe and Scope on?"
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Zorniak M, Sirtl S, Mahajan UM, Stubbe HC, Chapula M, Wosiewicz P, Hartleb M, Mayerle J, and Schulz C
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- Adult, Aged, Endoscopy, Female, Humans, Male, Middle Aged, RNA, Viral, Retrospective Studies, SARS-CoV-2, COVID-19, Infection Control, Pandemics
- Abstract
Background: The COVID-19-pandemic poses challenges to the medical system and especially to endoscopic staff and patients. National, European and International societies provided recommendations on how to safely perform endoscopic procedures during the current pandemic. Until now, the effect of the current pandemic on tertiary endoscopy centers has not been reported., Objective: The aim of this was to analyze the influence of the early SARS-CoV2-pandemic on endoscopic care and work flow in 2 European tertiary endoscopy units., Methods: Data from 2 tertiary endoscopy units (Katowice and Munich) were retrospectively collected during the early pandemic and compared to an equivalent pre-pandemic period. Data include procedures, complications, benchmarks, and influence on endoscopy training., Results: During the early pandemic, we noted a highly significant decrease (49.1%) in the overall number of all endoscopies with a significant increase in therapeutic procedures. Besides, there were no significant differences in the number of urgent endoscopic retrograde cholangiopancreatography or interventional endoscopic ultrasound procedures. The exceptional situation reduced endoscopic procedures performed by trainees significantly., Conclusions: The SARS-CoV2-pandemic halved the endoscopy service of 2 tertiary centers while maintaining an urgent therapeutic service. Recommended personal safety measures in endoscopy proved to be efficient and safe in preventing SARS-CoV2 infection of staff or spreading. Unnecessarily, the SARS-CoV2 pandemic prevented routine endoscopy training., (© 2020 S. Karger AG, Basel.)
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- 2021
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31. Prevalence, Resistance Rates, and Risk Factors of Pathogens in Routine Bile Cultures Obtained during Endoscopic Retrograde Cholangiography.
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Reiter FP, Obermeier W, Jung J, Denk G, Mahajan UM, De Toni EN, Schirra J, Mayerle J, and Schulz C
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- Anti-Bacterial Agents therapeutic use, Bacteria isolation & purification, Bile Ducts surgery, Drainage, Female, Fungi isolation & purification, Humans, Length of Stay, Microbial Sensitivity Tests, Prevalence, Risk Factors, Bile microbiology, Cholangiopancreatography, Endoscopic Retrograde, Drug Resistance, Microbial
- Abstract
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., (© 2020 S. Karger AG, Basel.)
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- 2021
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32. Aptamers: a novel targeted theranostic platform for pancreatic ductal adenocarcinoma.
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Li Q, Maier SH, Li P, Peterhansl J, Belka C, Mayerle J, and Mahajan UM
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- Humans, SELEX Aptamer Technique, Antineoplastic Agents therapeutic use, Aptamers, Nucleotide therapeutic use, Carcinoma, Pancreatic Ductal drug therapy, Molecular Targeted Therapy, Pancreatic Neoplasms drug therapy, Precision Medicine
- Abstract
Pancreatic ductal adenocarcinoma (PDAC) is an extremely challenging disease with a high mortality rate and a short overall survival time. The poor prognosis can be explained by aggressive tumor growth, late diagnosis, and therapy resistance. Consistent efforts have been made focusing on early tumor detection and novel drug development. Various strategies aim at increasing target specificity or local enrichment of chemotherapeutics as well as imaging agents in tumor tissue. Aptamers have the potential to provide early detection and permit anti-cancer therapy with significantly reduced side effects. These molecules are in-vitro selected single-stranded oligonucleotides that form stable three-dimensional structures. They are capable of binding to a variety of molecular targets with high affinity and specificity. Several properties such as high binding affinity, the in vitro chemical process of selection, a variety of chemical modifications of molecular platforms for diverse function, non-immunoreactivity, modification of bioavailability, and manipulation of pharmacokinetics make aptamers attractive targets compared to conventional cell-specific ligands. To explore the potential of aptamers for early diagnosis and targeted therapy of PDAC - as single agents and in combination with radiotherapy - we summarize the generation process of aptamers and their application as biosensors, biomarker detection tools, targeted imaging tracers, and drug-delivery carriers. We are furthermore discussing the current implementation aptamers in clinical trials, their limitations and possible future utilization.
- Published
- 2020
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33. Early trypsin activation develops independently of autophagy in caerulein-induced pancreatitis in mice.
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Malla SR, Krueger B, Wartmann T, Sendler M, Mahajan UM, Weiss FU, Thiel FG, De Boni C, Gorelick FS, Halangk W, Aghdassi AA, Reinheckel T, Gukovskaya AS, Lerch MM, and Mayerle J
- Subjects
- Animals, Autophagosomes metabolism, Endosomes metabolism, Male, Mice, Mice, Inbred C57BL, Pancreatitis chemically induced, Pancreatitis metabolism, Secretory Vesicles metabolism, Autophagy, Ceruletide toxicity, Pancreatitis pathology, Trypsin metabolism, Trypsinogen metabolism
- Abstract
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.
- Published
- 2020
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34. Downregulation of SFRP1 is a protumorigenic event in hepatoblastoma and correlates with beta-catenin mutations.
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Regel I, Eichenmüller M, Mahajan UM, Hagl B, Benitz S, Häberle B, Vokuhl C, von Schweinitz D, and Kappler R
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- Aged, Cell Line, Tumor, DNA Methylation, Down-Regulation, Female, Hep G2 Cells, Hepatoblastoma metabolism, Humans, Intercellular Signaling Peptides and Proteins biosynthesis, Liver Neoplasms metabolism, Male, Membrane Proteins biosynthesis, Middle Aged, Promoter Regions, Genetic, Wnt Signaling Pathway, beta Catenin metabolism, Hepatoblastoma genetics, Intercellular Signaling Peptides and Proteins genetics, Liver Neoplasms genetics, Membrane Proteins genetics, Mutation, beta Catenin genetics
- Abstract
Background: Hepatoblastoma (HB) and pediatric hepatocellular carcinoma (HCC) are the most common malignant liver tumors in childhood. Both tumor types exhibit genetic and epigenetic alterations in the WNT/β-catenin signaling pathway, which is a key regulator of liver progenitor cells in embryonic development. The tumors demonstrate a high rate of β-catenin mutations and gene expression changes of several WNT antagonists. However, the role of the WNT inhibitory factor secreted frizzled-related protein 1 (SFRP1) has not been addressed in pediatric liver cancer so far., Results: In our study, we investigated the gene expression level, DNA methylation status and functional relevance of SFRP1 in HB cell lines and in pediatric liver tumor patient samples. SFRP1 was downregulated due to DNA promoter methylation in all tested HB cell lines. Overexpression of SFRP1 in HB cell lines diminished tumor cell proliferation, colony formation and migration potential. In addition, the SFRP1-expressing HB cell lines showed reduced WNT/β-catenin signaling pathway activity and decreased expression of WNT target genes. To evaluate the utility of SFRP1 as a biomarker in pediatric liver cancer, we determined the gene expression level and DNA methylation status of SFRP1 in 45 pediatric liver tumor patient samples. The correlation analysis of different clinical parameters and tumor characteristics revealed a significant correlation of reduced SFRP1 expression with the presence of mutant β-catenin. The methylation status of SFRP1 was furthermore associated to a pediatric liver tumor type with HCC-like characteristics, TERT mutations and an older age at diagnosis., Conclusion: Altogether, our data demonstrate that the epigenetic suppression of the WNT/β-catenin antagonist SFRP1 has an important impact on the malignant behavior of HB cells. Although SFRP1 methylation is a common event in HCC-like pediatric liver tumors, its potential as a prognostic or diagnostic biomarker needs to be further investigated.
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- 2020
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35. Current Strategies and Future Perspectives for Precision Medicine in Pancreatic Cancer.
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Regel I, Mayerle J, and Mahajan UM
- Abstract
Current standard-of-care for patients with pancreatic ductal adenocarcinoma (PDAC) focusses on chemotherapeutic regimens and pancreatic cancer surgery. However, limited treatment options, late diagnosis in advanced tumor stages and the aggressive behavior of PDAC contribute to the high mortality of the disease. Consequently, there is an urgent need of precision medicine for pancreatic cancer patients. All over the world, numerous initiatives started in recent years to translate novel scientific discoveries into prospective clinical trials. One major approach pursues the stratification of PDAC patients according the tumor transcriptome to predict treatment response. Other strategies concentrate on genomic alterations and the identification of individualized targeted therapies. Further experimental studies are ongoing to detect novel biomarkers for cancer diagnosis, subtyping, treatment response prediction or clinical outcome. However, the challenge remains to transfer the knowledge into clinical practice. In this review, we summarize current literature and knowledge and highlight novel concepts of basic and clinical research uncovering suitable biomarkers and targeted therapies. Thus, we provide an overview of preclinical and clinical efforts of precision medicine in pancreatic cancer.
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- 2020
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36. The impact of physiological stress conditions on protein structure and trypsin inhibition of serine protease inhibitor Kazal type 1 (SPINK1) and its N34S variant.
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Buchholz I, Nagel F, Klein A, Wagh PR, Mahajan UM, Greinacher A, Lerch MM, Mayerle J, and Delcea M
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- Disease Progression, HEK293 Cells, Humans, Hydrogen-Ion Concentration, Mutation, Pancreatitis, Protein Conformation, Temperature, Trypsin Inhibitor, Kazal Pancreatic genetics, Stress, Physiological, Trypsin chemistry, Trypsin Inhibitor, Kazal Pancreatic chemistry
- Abstract
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 (K
D of 0.15 ± 0.06 nM) and its N34S variant (KD of 0.08 ± 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., (Copyright © 2019 The Author(s). Published by Elsevier B.V. All rights reserved.)- Published
- 2020
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37. NLRP3 Inflammasome Regulates Development of Systemic Inflammatory Response and Compensatory Anti-Inflammatory Response Syndromes in Mice With Acute Pancreatitis.
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Sendler M, van den Brandt C, Glaubitz J, Wilden A, Golchert J, Weiss FU, Homuth G, De Freitas Chama LL, Mishra N, Mahajan UM, Bossaller L, Völker U, Bröker BM, Mayerle J, and Lerch MM
- Subjects
- Acinar Cells, Adaptive Immunity, Animals, Arginine toxicity, Cells, Cultured, Ceruletide toxicity, Cytokines blood, Cytokines immunology, Disease Models, Animal, Heterocyclic Compounds, 4 or More Rings, Humans, Indenes, Injections, Intraperitoneal, Interleukin-18 immunology, Interleukin-18 metabolism, Macrophages immunology, Mice, Mice, Knockout, NLR Family, Pyrin Domain-Containing 3 Protein antagonists & inhibitors, NLR Family, Pyrin Domain-Containing 3 Protein genetics, Pancreas cytology, Pancreas immunology, Pancreas pathology, Pancreatitis chemically induced, Pancreatitis drug therapy, Primary Cell Culture, Sulfones, Systemic Inflammatory Response Syndrome blood, Systemic Inflammatory Response Syndrome drug therapy, Th2 Cells immunology, Th2 Cells metabolism, Furans administration & dosage, Inflammasomes immunology, NLR Family, Pyrin Domain-Containing 3 Protein immunology, Pancreatitis immunology, Sulfonamides administration & dosage, Systemic Inflammatory Response Syndrome immunology
- Abstract
Background & Aims: Pancreatitis starts with primarily sterile local inflammation that induces systemic inflammatory response syndrome, followed by compensatory anti-inflammatory response syndrome (CARS). We investigated the mechanisms of these processes in mice and human serum., Methods: We induced severe acute pancreatitis by partial duct ligation with caerulein stimulation or intraperitoneal injection of l-arginine in mice with deletion of interleukin (IL)12B, NLRP3, or IL18 and in mice given MCC950, a small molecule inhibitor of the NLRP3-inflammasome. Pancreata were collected from mice and analyzed by histology, and cytokine levels were measured in serum samples. We measured activation of adaptive immune responses in mice with pancreatitis by flow cytometry analysis of T cells (CD25 and CD69) isolated from the spleen. Differentiation of T-helper (Th1) cells, Th2 cells, and T-regulatory cells was determined by nuclear staining for TBET, GATA3, and FOXP3. We performed transcriptome analysis of mouse lymph nodes and bone marrow-derived macrophages after incubation with acini. We measured levels of cytokines in serum samples from patients with mild and severe acute pancreatitis., Results: Activation of the adaptive immune response in mice was initiated by macrophage-derived, caspase 1-processed cytokines and required activation of NLRP3 (confirmed in serum samples from patients with pancreatitis). Spleen cells from mice with pancreatitis had increases in Th2 cells but not in Th1 cells. Bone marrow-derived macrophages secreted IL1B and IL18, but not IL12, after co-incubation with pancreatic acini. T-cell activation and severity of acute pancreatitis did not differ significantly between IL12B-deficient and control mice. In contrast, NLRP3- or IL18-deficient mice had reduced activation of T cells and no increase in Th2 cell-mediated responses compared with control mice. The systemic type 2 immune response was mediated by macrophage-derived cytokines of the IL1 family. Specifically, IL18 induced a Th2 cell-mediated response in the absence of IL12. MCC950 significantly reduced neutrophil infiltration, T-cell activation, and disease severity in mice., Conclusions: In mice with severe pancreatitis, we found systemic inflammatory response syndrome and compensatory anti-inflammatory response syndrome developed in parallel. Infiltrating macrophages promote inflammation and simultaneously induce a Th2 cell-mediated response via IL18. Inhibition of NLRP3 reduces systemic inflammatory response syndrome and compensatory anti-inflammatory response syndrome and might be used to treat patients with severe pancreatitis., (Copyright © 2020 AGA Institute. Published by Elsevier Inc. All rights reserved.)
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- 2020
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38. The effects of hepatic steatosis on thromboxane A 2 induced portal hypertension.
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Zhang J, Schewe J, Li H, Makeschin MC, Mahajan UM, Gerbes AL, and Steib CJ
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- 15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic Acid pharmacology, Animals, Antigens, CD analysis, Antigens, Differentiation, Myelomonocytic analysis, Cell Count, Diet, High-Fat, Fatty Liver pathology, Fatty Liver physiopathology, Kupffer Cells chemistry, Kupffer Cells cytology, Perfusion methods, Portal Pressure physiology, Random Allocation, Rats, Rats, Sprague-Dawley, Receptors, Cell Surface analysis, Thromboxane A2 analogs & derivatives, Thromboxane B2 analysis, Vasoconstrictor Agents, Fatty Liver complications, Hypertension, Portal chemically induced, Portal Pressure drug effects, Thromboxane B2 biosynthesis, Zymosan pharmacology
- Abstract
Introduction and Aim: Thromboxane (TX) A
2 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., (Copyright © 2019 Elsevier España, S.L.U. All rights reserved.)- Published
- 2019
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39. Ring1b-dependent epigenetic remodelling is an essential prerequisite for pancreatic carcinogenesis.
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Benitz S, Straub T, Mahajan UM, Mutter J, Czemmel S, Unruh T, Wingerath B, Deubler S, Fahr L, Cheng T, Nahnsen S, Bruns P, Kong B, Raulefs S, Ceyhan GO, Mayerle J, Steiger K, Esposito I, Kleeff J, Michalski CW, and Regel I
- Subjects
- Animals, Carcinogenesis, Cell Culture Techniques, Disease Models, Animal, Mice, Mice, Knockout, Acinar Cells pathology, Epigenesis, Genetic physiology, Pancreatic Neoplasms etiology, Pancreatic Neoplasms pathology, Polycomb Repressive Complex 1 physiology, Ubiquitin-Protein Ligases physiology
- Abstract
Background and Aims: Besides well-defined genetic alterations, the dedifferentiation of mature acinar cells is an important prerequisite for pancreatic carcinogenesis. Acinar-specific genes controlling cell homeostasis are extensively downregulated during cancer development; however, the underlying mechanisms are poorly understood. Now, we devised a novel in vitro strategy to determine genome-wide dynamics in the epigenetic landscape in pancreatic carcinogenesis., Design: With our in vitro carcinogenic sequence, we performed global gene expression analysis and ChIP sequencing for the histone modifications H3K4me3, H3K27me3 and H2AK119ub. Followed by a comprehensive bioinformatic approach, we captured gene clusters with extensive epigenetic and transcriptional remodelling. Relevance of Ring1b-catalysed H2AK119ub in acinar cell reprogramming was studied in an inducible Ring1b knockout mouse model. CRISPR/Cas9-mediated Ring1b ablation as well as drug-induced Ring1b inhibition were functionally characterised in pancreatic cancer cells., Results: The epigenome is vigorously modified during pancreatic carcinogenesis, defining cellular identity. Particularly, regulatory acinar cell transcription factors are epigenetically silenced by the Ring1b-catalysed histone modification H2AK119ub in acinar-to-ductal metaplasia and pancreatic cancer cells. Ring1b knockout mice showed greatly impaired acinar cell dedifferentiation and pancreatic tumour formation due to a retained expression of acinar differentiation genes. Depletion or drug-induced inhibition of Ring1b promoted tumour cell reprogramming towards a less aggressive phenotype., Conclusions: Our data provide substantial evidence that the epigenetic silencing of acinar cell fate genes is a mandatory event in the development and progression of pancreatic cancer. Targeting the epigenetic repressor Ring1b could offer new therapeutic options., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2019. No commercial re-use. See rights and permissions. Published by BMJ.)
- Published
- 2019
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40. Cathepsin D Expression and Gemcitabine Resistance in Pancreatic Cancer.
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Mahajan UM, Goni E, Langhoff E, Li Q, Costello E, Greenhalf W, Kruger S, Ormanns S, Halloran C, Ganeh P, Marron M, Lämmerhirt F, Zhao Y, Beyer G, Weiss FU, Sendler M, Bruns CJ, Kohlmann T, Kirchner T, Werner J, D'Haese JG, von Bergwelt-Baildon M, Heinemann V, Neoptolemos JP, Büchler MW, Belka C, Boeck S, Lerch MM, and Mayerle J
- Abstract
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 (χ
2 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., (© The Author(s) 2020. Published by Oxford University Press.)- Published
- 2019
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41. Immune Cell and Stromal Signature Associated With Progression-Free Survival of Patients With Resected Pancreatic Ductal Adenocarcinoma.
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Mahajan UM, Langhoff E, Goni E, Costello E, Greenhalf W, Halloran C, Ormanns S, Kruger S, Boeck S, Ribback S, Beyer G, Dombroswki F, Weiss FU, Neoptolemos JP, Werner J, D'Haese JG, Bazhin A, Peterhansl J, Pichlmeier S, Büchler MW, Kleeff J, Ganeh P, Sendler M, Palmer DH, Kohlmann T, Rad R, Regel I, Lerch MM, and Mayerle J
- Subjects
- Adenocarcinoma mortality, Adenocarcinoma pathology, Adenocarcinoma surgery, Adult, Aged, Aged, 80 and over, Antigens, CD analysis, Carcinoma, Pancreatic Ductal mortality, Carcinoma, Pancreatic Ductal pathology, Carcinoma, Pancreatic Ductal surgery, Disease-Free Survival, Female, Humans, Male, Middle Aged, Pancreatic Neoplasms mortality, Pancreatic Neoplasms pathology, Pancreatic Neoplasms surgery, Adenocarcinoma immunology, Carcinoma, Pancreatic Ductal immunology, Lymphocytes, Tumor-Infiltrating immunology, Pancreatic Neoplasms immunology
- Abstract
Background & Aims: Changes to the microenvironment of pancreatic ductal adenocarcinomas (PDACs) have been associated with poor outcomes of patients. We studied the associations between composition of the pancreatic stroma (fibrogenic, inert, dormant, or fibrolytic stroma) and infiltration by inflammatory cells and times of progression-free survival (PFS) of patients with PDACs after resection., Methods: We obtained 1824 tissue microarray specimens from 385 patients included in the European Study Group for Pancreatic Cancer trial 1 and 3 and performed immunohistochemistry to detect alpha smooth muscle actin, type 1 collagen, CD3, CD4, CD8, CD68, CD206, and neutrophils. Tumors that expressed high and low levels of these markers were compared with patient outcomes using Kaplan-Meier curves and multivariable recursive partitioning for discrete-time survival tree analysis. Prognostic index was delineated by a multivariable Cox proportional hazards model of immune cell and stromal markers and PFS. Findings were validated using 279 tissue microarray specimens from 93 patients in a separate cohort., Results: Levels of CD3, CD4, CD8, CD68, and CD206 were independently associated with tumor recurrence. Recursive partitioning for discrete-time survival tree analysis identified a high level of CD3 as the strongest independent predictor for longer PFS. Tumors with levels of CD3 and high levels of CD206 associated with a median PFS time of 16.6 months and a median prognostic index of -0.32 (95% confidence interval [CI] -0.35 to -0.31), whereas tumors with low level of CD3 cell and low level of CD8 and high level of CD68 associated with a median PFS time of 7.9 months and a prognostic index of 0.32 (95% CI 0.050-0.32); we called these patterns histologic signatures. Stroma composition, when unassociated with inflammatory cell markers, did not associate significantly with PFS. In the validation cohort, the histologic signature resulted in an error matrix accuracy of predicted response of 0.75 (95% CI 0.64-0.83; accuracy P < .001)., Conclusions: In an analysis of PDAC tissue microarray specimens, we identified and validated a histologic signature, based on leukocyte and stromal factors, that associates with PFS times of patients with resected PDACs. Immune cells might affect the composition of the pancreatic stroma to affect progression of PDAC. These findings provide new insights into the immune response to PDAC., (Copyright © 2018 AGA Institute. Published by Elsevier Inc. All rights reserved.)
- Published
- 2018
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42. [Pancreatic Cancer in the Year 2018 - Room for Precision Medicine?]
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Simon O, Beyer G, Mahajan UM, and Mayerle J
- Subjects
- Antineoplastic Combined Chemotherapy Protocols adverse effects, Antineoplastic Combined Chemotherapy Protocols therapeutic use, Forecasting, Germany, Humans, Neoplasm Staging, Pancreatectomy methods, Pancreatic Neoplasms mortality, Pancreatic Neoplasms pathology, Survival Rate, Treatment Outcome, Pancreatic Neoplasms therapy, Precision Medicine trends
- Abstract
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., Competing Interests: Disclosure The authors report no conflicts of interest in this work., (© Georg Thieme Verlag KG Stuttgart · New York.)
- Published
- 2018
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43. Reply.
- Author
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Beyer G, Mahajan UM, Lerch MM, and Mayerle J
- Published
- 2018
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44. Cathepsin B-Mediated Activation of Trypsinogen in Endocytosing Macrophages Increases Severity of Pancreatitis in Mice.
- Author
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Sendler M, Weiss FU, Golchert J, Homuth G, van den Brandt C, Mahajan UM, Partecke LI, Döring P, Gukovsky I, Gukovskaya AS, Wagh PR, Lerch MM, and Mayerle J
- Subjects
- Adoptive Transfer, Animals, Cathepsin B deficiency, Cathepsin B genetics, Cathepsin L deficiency, Cathepsin L genetics, Cells, Cultured, Ceruletide, Coculture Techniques, Cytokines metabolism, Disease Models, Animal, Enzyme Activation, Genetic Predisposition to Disease, Humans, Hydrogen-Ion Concentration, Inflammation Mediators metabolism, Macrophages immunology, Macrophages pathology, Macrophages transplantation, Mice, Inbred C57BL, Mice, Knockout, NF-kappa B metabolism, NLR Family, Pyrin Domain-Containing 3 Protein deficiency, NLR Family, Pyrin Domain-Containing 3 Protein genetics, Necrosis, Pancreas immunology, Pancreas pathology, Pancreatectomy, Pancreatitis, Acute Necrotizing chemically induced, Pancreatitis, Acute Necrotizing immunology, Pancreatitis, Acute Necrotizing pathology, Phagocytosis, Phenotype, Severity of Illness Index, Time Factors, Cathepsin B metabolism, Endocytosis, Macrophages enzymology, Pancreas enzymology, Pancreatitis, Acute Necrotizing enzymology, Trypsinogen metabolism
- Abstract
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., (Copyright © 2018 AGA Institute. Published by Elsevier Inc. All rights reserved.)
- Published
- 2018
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45. Metabolic biomarker signature to differentiate pancreatic ductal adenocarcinoma from chronic pancreatitis.
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Mayerle J, Kalthoff H, Reszka R, Kamlage B, Peter E, Schniewind B, González Maldonado S, Pilarsky C, Heidecke CD, Schatz P, Distler M, Scheiber JA, Mahajan UM, Weiss FU, Grützmann R, and Lerch MM
- Subjects
- Adult, Aged, Carcinoma, Pancreatic Ductal pathology, Case-Control Studies, Diagnosis, Differential, Feasibility Studies, Female, Humans, Male, Metabolomics methods, Middle Aged, Neoplasm Staging, Pancreatic Neoplasms pathology, Sensitivity and Specificity, Biomarkers, Tumor blood, Carcinoma, Pancreatic Ductal diagnosis, Early Detection of Cancer methods, Pancreatic Neoplasms diagnosis, Pancreatitis, Chronic diagnosis
- Abstract
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., Competing Interests: Competing interests: None declared., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.)
- Published
- 2018
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46. Development and Validation of a Chronic Pancreatitis Prognosis Score in 2 Independent Cohorts.
- Author
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Beyer G, Mahajan UM, Budde C, Bulla TJ, Kohlmann T, Kuhlmann L, Schütte K, Aghdassi AA, Weber E, Weiss FU, Drewes AM, Olesen SS, Lerch MM, and Mayerle J
- Subjects
- Adult, Aged, Aged, 80 and over, Biomarkers blood, Body Mass Index, C-Reactive Protein analysis, Chi-Square Distribution, Disease Progression, Female, Germany, Glycated Hemoglobin analysis, Health Status, Humans, Length of Stay, Linear Models, Male, Middle Aged, Multivariate Analysis, Pain Measurement, Pancreatitis, Chronic blood, Pancreatitis, Chronic complications, Pancreatitis, Chronic therapy, Patient Readmission, Platelet Count, Predictive Value of Tests, Prognosis, Prospective Studies, Reproducibility of Results, Risk Factors, Severity of Illness Index, Time Factors, Young Adult, Decision Support Techniques, Pancreatitis, Chronic diagnosis
- Abstract
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., (Copyright © 2017 AGA Institute. Published by Elsevier Inc. All rights reserved.)
- Published
- 2017
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47. Tumour-specific delivery of siRNA-coupled superparamagnetic iron oxide nanoparticles, targeted against PLK1, stops progression of pancreatic cancer.
- Author
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Mahajan UM, Teller S, Sendler M, Palankar R, van den Brandt C, Schwaiger T, Kühn JP, Ribback S, Glöckl G, Evert M, Weitschies W, Hosten N, Dombrowski F, Delcea M, Weiss FU, Lerch MM, and Mayerle J
- Subjects
- Animals, Apoptosis drug effects, Cell Proliferation drug effects, Disease Models, Animal, Drug Delivery Systems methods, Drug Monitoring methods, Gene Silencing, Mice, Polo-Like Kinase 1, Antineoplastic Agents pharmacology, Carcinoma, Pancreatic Ductal drug therapy, Carcinoma, Pancreatic Ductal pathology, Cell Cycle Proteins genetics, Cell Cycle Proteins metabolism, Magnetite Nanoparticles therapeutic use, Pancreatic Neoplasms drug therapy, Pancreatic Neoplasms pathology, Protein Serine-Threonine Kinases genetics, Protein Serine-Threonine Kinases metabolism, Proto-Oncogene Proteins genetics, Proto-Oncogene Proteins metabolism, RNA, Small Interfering metabolism, RNA, Small Interfering pharmacology
- Abstract
Objective: Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive malignancies and is projected to be the second leading cause of cancer-related death by 2030. Despite extensive knowledge and insights into biological properties and genetic aberrations of PDAC, therapeutic options remain temporary and ineffective. One plausible explanation for the futile response to therapy is an insufficient and non-specific delivery of anticancer drugs to the tumour site., Design: Superparamagnetic iron oxide nanoparticles (SPIONs) coupled with siRNA directed against the cell cycle-specific serine-threonine-kinase, Polo-like kinase-1 (siPLK1-StAv-SPIONs), could serve a dual purpose for delivery of siPLK1 to the tumour and for non-invasive assessment of efficiency of delivery in vivo by imaging the tumour response. siPLK1-StAv-SPIONs were designed and synthesised as theranostics to function via a membrane translocation peptide with added advantage of driving endosomal escape for mediating transportation to the cytoplasm (myristoylated polyarginine peptides) as well as a tumour-selective peptide (EPPT1) to increase intracellular delivery and tumour specificity, respectively., Results: A syngeneic orthotopic as well as an endogenous cancer model was treated biweekly with siPLK1-StAv-SPIONs and tumour growth was monitored by small animal MRI. In vitro and in vivo experiments using a syngeneic orthotopic PDAC model as well as the endogenous LSL-Kras
G12D , LSL-Trp53R172H , Pdx-1-Cre model revealed significant accumulation of siPLK1-StAv-SPIONs in PDAC, resulting in efficient PLK1 silencing. Tumour-specific silencing of PLK1 halted tumour growth, marked by a decrease in tumour cell proliferation and an increase in apoptosis., Conclusions: Our data suggest siPLK1-StAv-SPIONs with dual specificity residues for tumour targeting and membrane translocation to represent an exciting opportunity for targeted therapy in patients with PDAC., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.)- Published
- 2016
- Full Text
- View/download PDF
48. Effect of oral administration of AZD8309, a CXCR2 antagonist, on the severity of experimental pancreatitis.
- Author
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Malla SR, Kärrman Mårdh C, Günther A, Mahajan UM, Sendler M, D'Haese J, Weiss FU, Lerch MM, Hansen MB, and Mayerle J
- Subjects
- Animals, Cell Movement drug effects, Ceruletide, Cytokines blood, Injections, Intraperitoneal, Male, Mice, Mice, Inbred C57BL, Neutrophils drug effects, Pancreas metabolism, Pancreas pathology, Pancreatitis chemically induced, Pancreatitis pathology, Peptide Hydrolases metabolism, Taurocholic Acid, Pancreatitis drug therapy, Pyrimidines therapeutic use, Receptors, Interleukin-8B antagonists & inhibitors
- Abstract
Introduction: Acute pancreatitis is a common gastrointestinal disorder burdened with a high mortality. Two pathophysiological events during experimental pancreatitis are thought to determine the clinical course: premature digestive protease activation and tissue infiltration by inflammatory cells. We have investigated the effect of AZD8309, a potent and orally bioavailable antagonist of the chemokine receptor CXCR2, which has been proposed to regulate the transmigration of neutrophils., Methods: Male C57BL6 mice (25-30 g) received gavage feeding of AZD8309 (50 mg/kg/BW) or mannitol (controls) twice daily starting 3 h prior to pancreatitis induction. Mild pancreatitis was induced by i.p. caerulein administration (50 μg/kg BW), severe pancreatitis by intraductal taurocholate (2%). Pancreas, lung, and serum was harvested up to 48 h after pancreatitis induction and used for histopathology, amylase, lipase, cathepsin B, trypsin, and elastase activity measurements, myeloperoxidase (MPO) content and cytokine concentrations., Results: Oral administration of AZD8309 significantly reduced MPO in the pancreas and lungs (8 h & 24 h) and reduced intrapancreatic trypsin and elastase activity (8 h) in caerulein-pancreatitis. In taurocholate-pancreatitis AZD8309 reduced cathepsin B activity and MPO. Serum cytokine levels were reduced by AZD8309 as well as histopathological damage., Conclusion: The CXCR2 antagonist AZD8309 reduced the transmigration of neutrophils as well as intrapancreatic protease activation in experimental pancreatitis. This effect was sufficient to reduce the overall severity of the disease. CXCR2 may therefore be a viable therapeutic target and AZD8309 a suitable agent for the treatment of acute pancreatitis., (Copyright © 2016 IAP and EPC. Published by Elsevier B.V. All rights reserved.)
- Published
- 2016
- Full Text
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49. Complement Component 5 Mediates Development of Fibrosis, via Activation of Stellate Cells, in 2 Mouse Models of Chronic Pancreatitis.
- Author
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Sendler M, Beyer G, Mahajan UM, Kauschke V, Maertin S, Schurmann C, Homuth G, Völker U, Völzke H, Halangk W, Wartmann T, Weiss FU, Hegyi P, Lerch MM, and Mayerle J
- Subjects
- Aniline Compounds pharmacology, Animals, Case-Control Studies, Ceruletide, Complement C5 deficiency, Complement C5 genetics, Disease Models, Animal, Fibrosis, Genetic Predisposition to Disease, Ligation, Mice, Inbred C57BL, Mice, Knockout, Pancreatic Ducts surgery, Pancreatic Stellate Cells drug effects, Pancreatic Stellate Cells immunology, Pancreatic Stellate Cells pathology, Pancreatitis, Chronic chemically induced, Pancreatitis, Chronic drug therapy, Pancreatitis, Chronic genetics, Pancreatitis, Chronic immunology, Pancreatitis, Chronic pathology, Phenotype, Polymorphism, Single Nucleotide, Receptor, Anaphylatoxin C5a antagonists & inhibitors, Receptor, Anaphylatoxin C5a metabolism, Tetrahydronaphthalenes pharmacology, Time Factors, Complement C5 metabolism, Pancreatic Stellate Cells metabolism, Pancreatitis, Chronic metabolism
- Abstract
Background & Aims: Little is known about the pathogenic mechanisms of chronic pancreatitis. We investigated the roles of complement component 5 (C5) in pancreatic fibrogenesis in mice and patients., Methods: Chronic pancreatitis was induced by ligation of the midpancreatic duct, followed by a single supramaximal intraperitoneal injection of cerulein, in C57Bl6 (control) and C5-deficient mice. Some mice were given injections of 2 different antagonists of the receptor for C5a over 21 days. In a separate model, mice were given injections of cerulein for 10 weeks to induce chronic pancreatitis. Direct effects of C5 were studied in cultured primary cells. We performed genotype analysis for the single-nucleotide polymorphisms rs 17611 and rs 2300929 in C5 in patients with pancreatitis and healthy individuals (controls). Blood cells from 976 subjects were analyzed by transcriptional profiling., Results: During the initial phase of pancreatitis, levels of pancreatic damage were similar between C5-deficient and control mice. During later stages of pancreatitis, C5-deficient mice and mice given injections of C5a-receptor antagonists developed significantly less pancreatic fibrosis than control mice. Primary pancreatic stellate cells were activated in vitro by C5a. There were no differences in the rs 2300929 SNP between subjects with or without pancreatitis, but the minor allele rs17611 was associated with a significant increase in levels of C5 in whole blood., Conclusions: In mice, loss of C5 or injection of a C5a-receptor antagonist significantly reduced the level of fibrosis of chronic pancreatitis, but this was not a consequence of milder disease in early stages of pancreatitis. C5 might be a therapeutic target for chronic pancreatitis., (Copyright © 2015 AGA Institute. Published by Elsevier Inc. All rights reserved.)
- Published
- 2015
- Full Text
- View/download PDF
50. Alteration in inflammatory/apoptotic pathway and histone modifications by nordihydroguaiaretic acid prevents acute pancreatitis in swiss albino mice.
- Author
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Mahajan UM, Gupta C, Wagh PR, Karpe PA, and Tikoo K
- Subjects
- Acute Disease, Animals, Anti-Inflammatory Agents pharmacology, Anti-Inflammatory Agents therapeutic use, Apoptosis drug effects, Caspase 3 genetics, Caspase 3 metabolism, Ceruletide adverse effects, Ceruletide pharmacology, Chaperonin 60 genetics, Chaperonin 60 metabolism, Histones genetics, Histones metabolism, In Situ Nick-End Labeling, Inflammation chemically induced, Inflammation pathology, Lipoxygenase Inhibitors pharmacology, Lipoxygenase Inhibitors therapeutic use, Male, Masoprocol pharmacology, Mice, Mitochondrial Proteins genetics, Mitochondrial Proteins metabolism, NF-kappa B genetics, NF-kappa B metabolism, Oxidative Stress drug effects, Pancreas metabolism, Pancreas pathology, Pancreatitis chemically induced, Pancreatitis pathology, Real-Time Polymerase Chain Reaction, Tumor Necrosis Factor-alpha genetics, Tumor Necrosis Factor-alpha metabolism, Inflammation drug therapy, Inflammation metabolism, Masoprocol therapeutic use, Pancreas drug effects, Pancreatitis drug therapy, Pancreatitis metabolism, Signal Transduction drug effects
- Abstract
Reactive oxygen radicals, pro-inflammatory mediators and cytokines have been implicated in caerulein induced acute pancreatitis. Nordihydroguaiaretic acid (NDGA), a plant lignin, has marked anti-inflammatory properties. The present study aimed to investigate the possible protective effect of NDGA against caerulein induced pancreatitis. Acute pancreatitis was induced by intraperitoneal administration of eight doses of caerulein in male swiss albino mice. NDGA was administered after 9 h of acute pancreatitis induction. Pancreatic damage and the protective effect of NDGA were assessed by oxidative stress parameters and histopathology of pancreas. The mRNA expression of heat shock proteins (DNAJ C15 and HSPD1) was examined by real-time RT-PCR analysis. Expression of HSP 27, NF-κB, TNF-α, p-p38, Bcl-2, p-PP2A, procaspase-3, caspase-3 and histone modifications were examined by western blotting. NDGA attenuated the oxidative stress, led to increased plasma α-amylase and decreased IGF-1 in AP mice. It modulated the mRNA and protein levels of heat shock proteins and reduced the expression of NF-κB, TNF-α and p-p38. It increased the number of TUNEL positive apoptotic cells in the pancreas of AP mice. In addition, NDGA prevented the changes in modifications of histone H3 in acute pancreatitis. To best of our knowledge, this is the first report which suggests that NDGA prevents the progression of acute pancreatitis by involving alteration of histone H3 modifications and modulating the expression of genes involved in inflammatory/apoptotic cascade, which may be responsible for decreased necrosis and increased apoptosis in this model of acute pancreatitis.
- Published
- 2011
- Full Text
- View/download PDF
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