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Nature Reviews. Gastroenterology &... May 2017Acinar cells in the adult pancreas show high plasticity and can undergo transdifferentiation to a progenitor-like cell type with ductal characteristics. This process,... (Review)
Review
Acinar cells in the adult pancreas show high plasticity and can undergo transdifferentiation to a progenitor-like cell type with ductal characteristics. This process, termed acinar-to-ductal metaplasia (ADM), is an important feature facilitating pancreas regeneration after injury. Data from animal models show that cells that undergo ADM in response to oncogenic signalling are precursors for pancreatic intraepithelial neoplasia lesions, which can further progress to pancreatic ductal adenocarcinoma (PDAC). As human pancreatic adenocarcinoma is often diagnosed at a stage of metastatic disease, understanding the processes that lead to its initiation is important for the discovery of markers for early detection, as well as options that enable an early intervention. Here, the critical determinants of acinar cell plasticity are discussed, in addition to the intracellular and extracellular signalling events that drive acinar cell metaplasia and their contribution to development of PDAC.
Topics: Acinar Cells; Animals; Carcinoma, Pancreatic Ductal; Cellular Reprogramming; Disease Models, Animal; Humans; Mice; Pancreatic Neoplasms
PubMed: 28270694
DOI: 10.1038/nrgastro.2017.12 -
Cellular and Molecular Life Sciences :... Jul 2023Pancreatic cancer is typically detected at an advanced stage, and is refractory to most forms of treatment, contributing to poor survival outcomes. The incidence of... (Review)
Review
Pancreatic cancer is typically detected at an advanced stage, and is refractory to most forms of treatment, contributing to poor survival outcomes. The incidence of pancreatic cancer is gradually increasing, linked to an aging population and increasing rates of obesity and pancreatitis, which are risk factors for this cancer. Sources of risk include adipokine signaling from fat cells throughout the body, elevated levels of intrapancreatic intrapancreatic adipocytes (IPAs), inflammatory signals arising from pancreas-infiltrating immune cells and a fibrotic environment induced by recurring cycles of pancreatic obstruction and acinar cell lysis. Once cancers become established, reorganization of pancreatic tissue typically excludes IPAs from the tumor microenvironment, which instead consists of cancer cells embedded in a specialized microenvironment derived from cancer-associated fibroblasts (CAFs). While cancer cell interactions with CAFs and immune cells have been the topic of much investigation, mechanistic studies of the source and function of IPAs in the pre-cancerous niche are much less developed. Intriguingly, an extensive review of studies addressing the accumulation and activity of IPAs in the pancreas reveals that unexpectedly diverse group of factors cause replacement of acinar tissue with IPAs, particularly in the mouse models that are essential tools for research into pancreatic cancer. Genes implicated in regulation of IPA accumulation include KRAS, MYC, TGF-β, periostin, HNF1, and regulators of ductal ciliation and ER stress, among others. These findings emphasize the importance of studying pancreas-damaging factors in the pre-cancerous environment, and have significant implications for the interpretation of data from mouse models for pancreatic cancer.
Topics: Mice; Animals; Pancreatic Neoplasms; Pancreatitis; Pancreas; Acinar Cells; Carcinoma, Pancreatic Ductal; Tumor Microenvironment
PubMed: 37452870
DOI: 10.1007/s00018-023-04855-z -
Gastroenterology May 2024Pancreatic ductal adenocarcinoma (PDAC) is characterized by desmoplastic stroma surrounding most tumors. Activated stromal fibroblasts, namely cancer-associated...
BACKGROUND & AIMS
Pancreatic ductal adenocarcinoma (PDAC) is characterized by desmoplastic stroma surrounding most tumors. Activated stromal fibroblasts, namely cancer-associated fibroblasts (CAFs), play a major role in PDAC progression. We analyzed whether CAFs influence acinar cells and impact PDAC initiation, that is, acinar-to-ductal metaplasia (ADM). ADM connection with PDAC pathophysiology is indicated, but not yet established. We hypothesized that CAF secretome might play a significant role in ADM in PDAC initiation.
METHODS
Mouse and human acinar cell organoids, acinar cells cocultured with CAFs and exposed to CAF-conditioned media, acinar cell explants, and CAF cocultures were examined by means of quantitative reverse transcription polymerase chain reaction, RNA sequencing, immunoblotting, and confocal microscopy. Data from liquid chromatography with tandem mass spectrometry analysis of CAF-conditioned medium and RNA sequencing data of acinar cells post-conditioned medium exposure were integrated using bioinformatics tools to identify the molecular mechanism for CAF-induced ADM. Using confocal microscopy, immunoblotting, and quantitative reverse transcription polymerase chain reaction analysis, we validated the depletion of a key signaling axis in the cell line, acinar explant coculture, and mouse cancer-associated fibroblasts (mCAFs).
RESULTS
A close association of acino-ductal markers (Ulex europaeus agglutinin 1, amylase, cytokeratin-19) and mCAFs (α-smooth muscle actin) in LSL-Kras; LSL-Trp53; Pdx1 (KPC) and LSL-Kras; Pdx1 (KC) autochthonous progression tumor tissue was observed. Caerulein treatment-induced mCAFs increased cytokeratin-19 and decreased amylase in wild-type and KC pancreas. Likewise, acinar-mCAF cocultures revealed the induction of ductal transdifferentiation in cell line, acinar-organoid, and explant coculture formats in WT and KC mice pancreas. Proteomic and transcriptomic data integration revealed a novel laminin α5/integrinα4/stat3 axis responsible for CAF-mediated acinar-to-ductal cell transdifferentiation.
CONCLUSIONS
Results collectively suggest the first evidence for CAF-influenced acino-ductal phenotypic switchover, thus highlighting the tumor microenvironment role in pancreatic carcinogenesis inception.
Topics: Animals; Humans; Mice; Acinar Cells; Cancer-Associated Fibroblasts; Carcinoma, Pancreatic Ductal; Cell Line, Tumor; Cell Transdifferentiation; Coculture Techniques; Culture Media, Conditioned; Laminin; Metaplasia; Organoids; Pancreatic Neoplasms; Signal Transduction; Tumor Microenvironment
PubMed: 38154529
DOI: 10.1053/j.gastro.2023.12.018 -
Cancer Discovery Mar 2019Pancreatic ductal adenocarcinoma (PDA) has a poor prognosis, and new strategies for prevention and treatment are urgently needed. We previously reported that histone H4...
Pancreatic ductal adenocarcinoma (PDA) has a poor prognosis, and new strategies for prevention and treatment are urgently needed. We previously reported that histone H4 acetylation is elevated in pancreatic acinar cells harboring mutations prior to the appearance of premalignant lesions. Because acetyl-CoA abundance regulates global histone acetylation, we hypothesized that altered acetyl-CoA metabolism might contribute to metabolic or epigenetic alterations that promote tumorigenesis. We found that acetyl-CoA abundance is elevated in -mutant acinar cells and that its use in the mevalonate pathway supports acinar-to-ductal metaplasia (ADM). Pancreas-specific loss of the acetyl-CoA-producing enzyme ATP-citrate lyase (ACLY) accordingly suppresses ADM and tumor formation. In PDA cells, growth factors promote AKT-ACLY signaling and histone acetylation, and both cell proliferation and tumor growth can be suppressed by concurrent BET inhibition and statin treatment. Thus, KRAS-driven metabolic alterations promote acinar cell plasticity and tumor development, and targeting acetyl-CoA-dependent processes exerts anticancer effects. SIGNIFICANCE: Pancreatic cancer is among the deadliest of human malignancies. We identify a key role for the metabolic enzyme ACLY, which produces acetyl-CoA, in pancreatic carcinogenesis. The data suggest that acetyl-CoA use for histone acetylation and in the mevalonate pathway facilitates cell plasticity and proliferation, suggesting potential to target these pathways...
Topics: Acetyl Coenzyme A; Acetylation; Acinar Cells; Animals; Carcinogenesis; Carcinoma, Pancreatic Ductal; Cell Proliferation; Female; Genes, ras; Heterografts; Histones; Humans; Male; Mice, Inbred C57BL; Mice, Knockout; Mice, Transgenic; Mutation; Pancreatic Neoplasms; Protein Processing, Post-Translational; Signal Transduction
PubMed: 30626590
DOI: 10.1158/2159-8290.CD-18-0567 -
JCI Insight Nov 2022Acute pancreatitis (AP) is a local and/or systemic inflammatory disease that starts with acinar cell injury and necrosis; it has no effective medical treatment and thus...
Acute pancreatitis (AP) is a local and/or systemic inflammatory disease that starts with acinar cell injury and necrosis; it has no effective medical treatment and thus remains a life-threatening condition. Interleukin-37 (IL-37), a natural immunomodulator, has demonstrated an antiinflammatory effect; however, the role of IL-37 in AP remains unknown. The serum IL-37 levels of 39 healthy controls and 94 patients with AP were measured. Cholecystokinin was applied to induce pancreatic acinar cell injury in vitro. Classical experimental AP models, such as caerulein, l-arginine, and taurolithocholic acid 3-sulfate disodium salt, were included in the in vivo study. A transgenic mouse model with the IL-37 gene and administration of recombinant IL-37 were used to further investigate the function of IL-37 in AP. Pancreas-specific gasdermin D-knockout (GSDMD-knockout) mice were used to explore the protective mechanism of IL-37. Our results showed that serum IL-37 levels in humans were negatively correlated with the severity of AP. Furthermore, IL-37-transgenic mice and supplementation with recombinant IL-37 could both protect against AP. Mechanistically, IL-37 was able to suppress pyroptosis of injured acinar cells, and specific depletion of GSDMD in the pancreas counteracted the protective effect of IL-37. Our study demonstrates that IL-37 protects against acinar cell pyroptosis in AP.
Topics: Animals; Humans; Mice; Acinar Cells; Acute Disease; Interleukins; Mice, Knockout; Mice, Transgenic; Pancreatitis; Pyroptosis
PubMed: 36166295
DOI: 10.1172/jci.insight.161244 -
Gastroenterology Jul 2022Mitochondrial dysfunction disrupts the synthesis and secretion of digestive enzymes in pancreatic acinar cells and plays a primary role in the etiology of exocrine...
BACKGROUND & AIMS
Mitochondrial dysfunction disrupts the synthesis and secretion of digestive enzymes in pancreatic acinar cells and plays a primary role in the etiology of exocrine pancreas disorders. However, the transcriptional mechanisms that regulate mitochondrial function to support acinar cell physiology are poorly understood. Here, we aim to elucidate the function of estrogen-related receptor γ (ERRγ) in pancreatic acinar cell mitochondrial homeostasis and energy production.
METHODS
Two models of ERRγ inhibition, GSK5182-treated wild-type mice and ERRγ conditional knock-out (cKO) mice, were established to investigate ERRγ function in the exocrine pancreas. To identify the functional role of ERRγ in pancreatic acinar cells, we performed histologic and transcriptome analysis with the pancreas isolated from ERRγ cKO mice. To determine the relevance of these findings for human disease, we analyzed transcriptome data from multiple independent human cohorts and conducted genetic association studies for ESRRG variants in 2 distinct human pancreatitis cohorts.
RESULTS
Blocking ERRγ function in mice by genetic deletion or inverse agonist treatment results in striking pancreatitis-like phenotypes accompanied by inflammation, fibrosis, and cell death. Mechanistically, loss of ERRγ in primary acini abrogates messenger RNA expression and protein levels of mitochondrial oxidative phosphorylation complex genes, resulting in defective acinar cell energetics. Mitochondrial dysfunction due to ERRγ deletion further triggers autophagy dysfunction, endoplasmic reticulum stress, and production of reactive oxygen species, ultimately leading to cell death. Interestingly, ERRγ-deficient acinar cells that escape cell death acquire ductal cell characteristics, indicating a role for ERRγ in acinar-to-ductal metaplasia. Consistent with our findings in ERRγ cKO mice, ERRγ expression was significantly reduced in patients with chronic pancreatitis compared with normal subjects. Furthermore, candidate locus region genetic association studies revealed multiple single nucleotide variants for ERRγ that are associated with chronic pancreatitis.
CONCLUSIONS
Collectively, our findings highlight an essential role for ERRγ in maintaining the transcriptional program that supports acinar cell mitochondrial function and organellar homeostasis and provide a novel molecular link between ERRγ and exocrine pancreas disorders.
Topics: Acinar Cells; Animals; Estrogens; Humans; Mice; Mice, Knockout; Pancreas; Pancreas, Exocrine; Pancreatitis, Chronic
PubMed: 35461826
DOI: 10.1053/j.gastro.2022.04.013 -
Gastroenterology May 2018Acute pancreatitis (AP) is characterized by severe inflammation and acinar cell death. Transmembrane protein 173 (TMEM173 or STING) is a DNA sensor adaptor protein on...
BACKGROUND & AIMS
Acute pancreatitis (AP) is characterized by severe inflammation and acinar cell death. Transmembrane protein 173 (TMEM173 or STING) is a DNA sensor adaptor protein on immune cells that recognizes cytosolic nucleic acids and transmits signals that activate production of interferons and the innate immune response. We investigated whether leukocyte STING signaling mediates inflammation in mice with AP.
METHODS
We induced AP in C57BL/6J mice (control) and C57BL/6J-Tmem173gt/J mice (STING-knockout mice) by injection of cerulein or placement on choline-deficient DL-ethionine supplemented diet. In some mice, STING signaling was induced by administration of a pharmacologic agonist. AP was also induced in C57BL/6J mice with bone marrow transplants from control or STING-knockout mice and in mice with disruption of the cyclic GMP-AMP synthase (Cgas) gene. Pancreata were collected, analyzed by histology, and acini were isolated and analyzed by flow cytometry, quantitative polymerase chain reaction, immunoblots, and enzyme-linked immunosorbent assay. Bone-marrow-derived macrophages were collected from mice and tested for their ability to detect DNA from dying acinar cells in the presence and absence of deoxyribonuclease (DNaseI).
RESULTS
STING signaling was activated in pancreata from mice with AP but not mice without AP. STING-knockout mice developed less severe AP (less edema, inflammation, and markers of pancreatic injury) than control mice, whereas mice given a STING agonist developed more severe AP than controls. In immune cells collected from pancreata, STING was expressed predominantly in macrophages. Levels of cGAS were increased in mice with vs without AP, and cGAS-knockout mice had decreased edema, inflammation, and other markers of pancreatic injury upon induction of AP than control mice. Wild-type mice given bone marrow transplants from STING-knockout mice had less pancreatic injury and lower serum levels of lipase and pancreatic trypsin activity following induction of AP than mice given wild-type bone marrow. DNA from dying acinar cells activated STING signaling in macrophages, which was inhibited by addition of DNaseI.
CONCLUSIONS
In mice with AP, STING senses acinar cell death (by detecting DNA from dying acinar cells) and activates a signaling pathway that promotes inflammation. Macrophages express STING and activate pancreatic inflammation in AP.
Topics: Acinar Cells; Acute Disease; Animals; Cell Death; Ceruletide; Disease Models, Animal; Inflammation; Macrophages; Membrane Proteins; Mice; Mice, Inbred C57BL; Mice, Knockout; Nucleotides, Cyclic; Pancreas; Pancreatitis; Signal Transduction
PubMed: 29425920
DOI: 10.1053/j.gastro.2018.01.065 -
Theranostics 2021Recent studies have proven that the overall pathophysiology of pancreatitis involves not only the pancreatic acinar cells but also duct cells, however, pancreatic duct...
Recent studies have proven that the overall pathophysiology of pancreatitis involves not only the pancreatic acinar cells but also duct cells, however, pancreatic duct contribution in acinar cells homeostasis is poorly known and the molecular mechanisms leading to acinar insult and acute pancreatitis (AP) are unclear. Our previous work also showed that S100A9 protein level was notably increased in AP rat pancreas through iTRAQ-based quantitative proteomic analysis. Therefore, we investigated the actions of injured duct cells on acinar cells and the S100A9-related effects and mechanisms underlying AP pathology in the present paper. In this study, we constructed S100A9 knockout (s100a9) mice and an coculture system for pancreatic duct cells and acinar cells. Moreover, a variety of small molecular inhibitors of S100A9 were screened from ChemDiv through molecular docking and virtual screening methods. We found that the upregulation of S100A9 induces cell injury and inflammatory response via NLRP3 activation by targeting VNN1-mediated ROS release; and loss of S100A9 decreases AP injury and . Moreover, molecular docking and mutant plasmid experiments proved that S100A9 has a direct interaction with VNN1 through the salt bridges formation of Lys57 and Glu92 residues in S100A9 protein. We further found that compounds CHNO and CHFNOS can significantly improve AP injury and through inhibiting S100A9-VNN1 interaction. Our study showed the important regulatory effect of S100A9 on pancreatic duct injury during AP and revealed that inhibition of the S100A9-VNN1 interaction may be a key therapeutic target for this disease.
Topics: Acinar Cells; Amidohydrolases; Animals; Calgranulin B; Cell Line; GPI-Linked Proteins; Humans; Inflammation; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Molecular Docking Simulation; NLR Family, Pyrin Domain-Containing 3 Protein; Pancreatic Ducts; Pancreatitis; Reactive Oxygen Species; Small Molecule Libraries
PubMed: 33754072
DOI: 10.7150/thno.54245 -
Autophagy Nov 2020Pancreatitis is a common, sometimes fatal, disease of exocrine pancreas, initiated by damaged acinar cells. Recent studies implicate disordered macroautophagy/autophagy...
Pancreatitis is a common, sometimes fatal, disease of exocrine pancreas, initiated by damaged acinar cells. Recent studies implicate disordered macroautophagy/autophagy in pancreatitis pathogenesis. ATG8/LC3 protein is critical for autophagosome formation and a widely used marker of autophagic vacuoles. Transgenic GFP-LC3 mice are a valuable tool to investigate autophagy ; however, comparison of homeostatic and disease responses between GFP-LC3 and wild-type (WT) mice has not been done. We examined the effects of GFP-LC3 expression on autophagy, acinar cell function, and experimental pancreatitis. Unexpectedly, GFP-LC3 expression markedly increased endogenous LC3-II level in pancreas, caused by downregulation of ATG4B, the protease that deconjugates/delipidates LC3-II. By contrast, GFP-LC3 expression had lesser or no effect on autophagy in liver, lung and spleen. Autophagic flux analysis showed that autophagosome formation in GFP-LC3 acinar cells increased 3-fold but was not fully counterbalanced by increased autophagic degradation. Acinar cell () pancreatitis inhibited autophagic flux in WT and essentially blocked it in GFP-LC3 cells. pancreatitis caused autophagy impairment in WT mice, manifest by upregulation of LC3-II and SQSTM1/p62, increased number and size of autophagic vacuoles, and decreased level of TFEB, all of which were exacerbated in GFP-LC3 mice. GFP-LC3 expression affected key pancreatitis responses; most dramatically, it worsened increases in serum AMY (amylase), a diagnostic marker of acute pancreatitis, in several mouse models. The results emphasize physiological importance of autophagy for acinar cell function, demonstrate organ-specific effects of GFP-LC3 expression, and indicate that application of GFP-LC3 mice in disease models should be done with caution.: AP: acute pancreatitis; Arg-AP: L-arginine-induced acute pancreatitis; ATG: autophagy-related (protein); AVs: autophagic vacuoles; CCK: cholecystokinin-8; CDE: choline-deficient, D,L-ethionine supplemented diet; CER: caerulein (ortholog of CCK); CTSB: cathepsin B; CTSD: cathepsin D; CTSL: cathepsin L; ER: endoplasmic reticulum; LAMP: lysosomal-associated membrane protein; MAP1LC3/LC3: microtubule-associated protein 1 light chain 3; TEM: transmission electron microscopy; TFEB: transcription factor EB; ZG: zymogen granule(s).
Topics: Acinar Cells; Animals; Autophagosomes; Autophagy; Disease Models, Animal; Endoplasmic Reticulum; Lysosomes; Mice, Transgenic; Pancreas, Exocrine; Pancreatitis
PubMed: 31942816
DOI: 10.1080/15548627.2020.1715047 -
Mucosal Immunology Mar 2017The conventional view of the pathogenesis of acute and chronic pancreatitis is that it is due to a genetic- or environment-based abnormality of intracellular acinar... (Review)
Review
The conventional view of the pathogenesis of acute and chronic pancreatitis is that it is due to a genetic- or environment-based abnormality of intracellular acinar trypsinogen activation and thus to the induction of acinar cell injury that, in turn, sets in motion an intra-pancreatic inflammatory process. More recent studies, reviewed here, present strong evidence that while such trypsinogen activation is likely a necessary first step in the inflammatory cascade underlying pancreatitis, sustained pancreatic inflammation is dependent on damage-associated molecular patterns-mediated cytokine activation causing the translocation of commensal (gut) organisms into the circulation and their induction of innate immune responses in acinar cells. Quite unexpectedly, these recent studies reveal that the innate responses involve activation of responses by an innate factor, nucleotide-binding oligomerization domain 1 (NOD1), and that such NOD1 responses have a critical role in the activation/production of nuclear factor-kappa B and type I interferon. In addition, they reveal that chronic inflammation and its accompanying fibrosis are dependent on the generation of IL-33 by injured acinar cells and its downstream induction of T cells producing IL-13. These recent studies thus establish that pancreatitis is quite a unique form of inflammation and one susceptible to newer, more innovative therapy.
Topics: Acinar Cells; Animals; Fibrosis; Gastrointestinal Microbiome; Gene-Environment Interaction; Humans; Immunity, Innate; Inflammation; Interferon Type I; Interleukin-33; NF-kappa B; Nod1 Signaling Adaptor Protein; Pancreas; Pancreatitis; T-Lymphocytes
PubMed: 27848953
DOI: 10.1038/mi.2016.101