Metabolic compartmentalization of stroma-rich tumors, like pancreatic ductal adenocarcinoma (PDAC), greatly contributes to malignancy. This involves cancer cells importing lactate from the microenvironment (reverse Warburg cells) through monocarboxylate transporter-1 (MCT1) along with substantial phenotype alterations. Here, we report that the reverse Warburg phenotype of PDAC cells compensated for the shortage of glutamine as an essential metabolite for redox homeostasis.
View Article and Find Full Text PDFEur J Intern Med
May 2023
Introduction: High-power short-duration ablation (HPSD) is an effective therapy for atrial fibrillation with thermal esophageal injury as a rare but relevant side effect.
Aim And Methods: In this retrospective single-center analysis we evaluated the incidence and relevance of ablation-induced findings and the prevalence of ablation-independent incidental gastrointestinal findings. For 15 months all patients undergoing ablation were screened by postablation esophagogastroduodenoscopy.
The emergence of resistance to systemic therapies in pancreatic ductal adenocarcinoma (PDAC) is still a major obstacle in clinical practice. Both, constitutive and inducible NF-κB activity are known as key players in this context. To identify differentially expressed and TRAIL resistance mediating NF-κB target genes, TRAIL sensitive and resistant PDAC cell lines were analyzed by transcriptome assays.
View Article and Find Full Text PDFTumor-related death is primarily caused by metastasis; consequently, understanding, preventing, and treating metastasis is essential to improving clinical outcomes. Metastasis is mainly governed by the dissemination of tumor cells in the systemic circulation: so-called circulating tumor cells (CTCs). CTCs typically arise from epithelial tumor cells that undergo epithelial-to-mesenchymal transition (EMT), resulting in the loss of cell-cell adhesions and polarity, and the reorganization of the cytoskeleton.
View Article and Find Full Text PDFObesity and obesity-associated diseases represent one of the key health challenges of our time. In this context, aberrant hepatic lipid accumulation is a central pathological aspect of non-alcoholic fatty liver disease (NAFLD). By comparing methylation signatures of liver biopsies before and after bariatric surgery, we recently demonstrated the strong enrichment of differentially methylated heat shock factor 1 (HSF1) binding sites (>400-fold) in the process of liver remodeling, indicating a crucial role of HSF1 in modulating central aspects of NAFLD pathogenesis.
View Article and Find Full Text PDFBackground: Oncogenic Kras initiates and drives carcinogenesis in the pancreas by complex signaling networks, including activation of the NFκB pathway. Although recent evidence has shown that oncogenic gains in Nfκb2 collaborate with Kras in the carcinogenesis, no data at the level of genetics for the contribution of Nfκb2 is available so far.
Methods: We used Nfkb2 knock-out mice to decipher the role of the gene in Kras-driven carcinogenesis in vivo.
• stress pathways including the ER stress, the proteasome and the unfolded protein response (UPR) are increasingly reported to be suitable targets in PDAC. • UAE1 is the most abundant of two ubiquitin activating enzymes (UAE) regulating the initial step of the ER stress associated protein degradation (ERAD) pathway. • The group of Rehemtulla elegantly showed that TAK-243, a small molecule inhibitor of Ubiquitin activating enzyme 1 (UAE1) nduced apoptosis in PDAC cells and a subcutaneous mouse model of the disease.
View Article and Find Full Text PDFWith a five-year survival rate under 9%, pancreatic ductal adenocarcinoma (PDAC) represents one of the deadliest tumors. Although the treatment options are slightly improving, PDAC is the second leading cause of cancer related death in 2020 in the US. In addition to a pronounced desmoplastic stroma reaction, pancreatic cancer is characterized by one of the lowest levels of oxygen availability within the tumor mass and these hypoxic conditions are known to contribute to tumor development and progression.
View Article and Find Full Text PDFCancers (Basel)
December 2019
This series of 10 articles (four original articles, six reviews) is presented by international leaders in the field of NF-κB signaling in cancer and inflammation [...
View Article and Find Full Text PDFPancreatic cancer is one of the carcinomas with the worst prognoses, as shown by its five-year survival rate of 9%. Although there have been new therapeutic innovations, the effectiveness of these therapies is still limited, resulting in pancreatic ductal adenocarcinoma (PDAC) becoming the second leading cause of cancer-related death in 2020 in the US. In addition to tumor cell intrinsic resistance mechanisms, this disease exhibits a complex stroma consisting of fibroblasts, immune cells, neuronal and vascular cells, along with extracellular matrix, all conferring therapeutic resistance by several mechanisms.
View Article and Find Full Text PDFPancreatic ductal adenocarcinoma (PDAC) is one of the most lethal malignant neoplasms and registers rising death rates in western countries. Due to its late detection in advanced stages, its extremely aggressive nature and the minimal effectiveness of currently available therapies, PDAC is a challenging problem in the clinical field. One characteristic of PDAC is a distinct desmoplasia consisting of fibroblasts, endothelial and immune cells as well as non-cellular components, contributing to therapy resistance.
View Article and Find Full Text PDFFOXO3 is consistently annotated as a human longevity gene. However, functional variants and underlying mechanisms for the association remain unknown. Here, we perform resequencing of the FOXO3 locus and single-nucleotide variant (SNV) genotyping in three European populations.
View Article and Find Full Text PDFBiochim Biophys Acta Mol Cell Res
May 2017
Pancreatic ductal adenocarcinoma (PDAC) represents one of the deadliest cancers. From a clinical view, the transcription factor NF-κB is of particular importance, since this pathway confers apoptosis resistance and limits drug efficacy. Whereas the role of the most abundant NF-κB subunit p65/RelA in therapeutic resistance is well documented, only little knowledge of the RelA downstream targets and their functional relevance in TRAIL mediated apoptosis in PDAC is available.
View Article and Find Full Text PDFNrf2 has gained great attention with respect to its pivotal role in cell and tissue protection. Primarily defending cells against metabolic, xenobiotic and oxidative stress, Nrf2 is essential for maintaining tissue integrity. Owing to these functions, Nrf2 is regarded as a promising drug target in the chemoprevention of diseases, including cancer.
View Article and Find Full Text PDFAlthough nuclear factor E2-related factor-2 (Nrf2) protects from carcinogen-induced tumorigenesis, underlying the rationale for using Nrf2 inducers in chemoprevention, this antioxidative transcription factor may also act as a proto-oncogene. Thus, an enhanced Nrf2 activity promotes formation and chemoresistance of colon cancer. One mechanism causing persistent Nrf2 activation is the adaptation of epithelial cells to oxidative stress during chronic inflammation, e.
View Article and Find Full Text PDFAm J Physiol Gastrointest Liver Physiol
April 2013
Although a profound barrier dysfunction has been reported, little is known about the pathophysiological mechanism evoking gastrointestinal graft-vs.-host disease (GI-GvHD) and apparent therapeutic options. The aim of this study was to evaluate the influence of oral glutamine on the course of GI-GvHD in an acute semiallogenic graft-vs.
View Article and Find Full Text PDFPancreatic ductal adenocarcinoma (PDAC) and chronic pancreatitis, representing one risk factor for PDAC, are characterized by a marked desmoplasia enriched of pancreatic myofibroblasts (PMFs). Thus, PMFs are thought to essentially promote pancreatic tumorigenesis. We recently demonstrated that the adhesion molecule L1CAM is involved in epithelial-mesenchymal transition of PMF-cocultured H6c7 human ductal epithelial cells and that L1CAM is expressed already in ductal structures of chronic pancreatitis with even higher elevation in primary tumors and metastases of PDAC patients.
View Article and Find Full Text PDFAdaptation of epithelial cells to persistent oxidative stress plays an important role in inflammation-associated carcinogenesis. This adaptation process involves activation of Nrf2 (nuclear factor-E2-related factor-2), which has been recently shown to contribute to carcinogenesis through the induction of proteasomal gene expression and proteasome activity. To verify this possible link between inflammation, oxidative stress, and Nrf2-dependent proteasome activation, we explored the impact of inflammatory (M1) macrophages on the human colon epithelial cell line NCM460.
View Article and Find Full Text PDFMembers of the Slug/Snail family of transcription factors are thought to drive epithelial-mesenchymal-transition (EMT) in preneoplastic epithelial cells, thereby contributing to malignant transformation. One mediator in the EMT of pancreatic ductal adenocarcinoma (PDAC) cells and a potential target gene of Slug is the cellular adhesion molecule L1CAM. Using the human pancreatic ductal epithelial cell line H6c7 and the PDAC cell line Panc1, we could show that along with TGF-β1-induced EMT, L1CAM expression is increased in a Slug- but not Snail-dependent fashion.
View Article and Find Full Text PDFBackground: The L1 cell adhesion molecule (L1CAM) was originally identified as a neural adhesion molecule involved in axon guidance. In many human epithelial carcinomas L1CAM is overexpressed and thereby augments cell motility, invasion and metastasis formation. L1CAM positive carcinomas are associated with bad prognosis.
View Article and Find Full Text PDFPancreatic ductal adenocarcinoma (PDAC) is thought to originate from ductal structures, exhibiting strong desmoplastic reaction with stromal pancreatic myofibroblasts (PMF), which are supposed to drive PDAC tumorigenesis. Previously, we observed high expression of the adhesion molecule L1CAM (CD171) in PDAC cells accounting for chemoresistance. Thus, this study aimed to investigate whether PMFs are involved in the induction of tumoral L1CAM and whether this contributes to malignant transformation of pancreatic ductal cells and PDAC tumorigenesis.
View Article and Find Full Text PDFWe recently showed that the adhesion molecule L1CAM (CD171) is overexpressed in pancreatic adenocarcinoma (PDAC) essentially contributing to chemoresistance of PDAC cells. In search of the mechanisms of this effect we now identified alpha5-integrin as the L1CAM ligand being essential for L1CAM-mediated chemoresistance of these highly malignant tumor cells. Thus, blockade or knock-down of alpha5-integrin in the L1CAM expressing PDAC cell lines PT45-P1res, Colo357 and Panc1 increased anti-cancer drug sensitivity.
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