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  1. Article ; Online: Deficiencies of the lipid-signaling enzymes phospholipase D1 and D2 alter cytoskeletal organization, macrophage phagocytosis, and cytokine-stimulated neutrophil recruitment.

    Ali, Wahida H / Chen, Qin / Delgiorno, Kathleen E / Su, Wenjuan / Hall, Jason C / Hongu, Tsunaki / Tian, Huasong / Kanaho, Yasunori / Di Paolo, Gilbert / Crawford, Howard C / Frohman, Michael A

    PloS one

    2013  Volume 8, Issue 1, Page(s) e55325

    Abstract: Cell migration and phagocytosis ensue from extracellular-initiated signaling cascades that orchestrate dynamic reorganization of the actin cytoskeleton. The reorganization is mediated by effector proteins recruited to the site of activity by locally- ... ...

    Abstract Cell migration and phagocytosis ensue from extracellular-initiated signaling cascades that orchestrate dynamic reorganization of the actin cytoskeleton. The reorganization is mediated by effector proteins recruited to the site of activity by locally-generated lipid second messengers. Phosphatidic acid (PA), a membrane phospholipid generated by multiple enzyme families including Phospholipase D (PLD), has been proposed to function in this role. Here, we show that macrophages prepared from mice lacking either of the classical PLD isoforms PLD1 or PLD2, or wild-type macrophages whose PLD activity has been pharmacologically inhibited, display isoform-specific actin cytoskeleton abnormalities that likely underlie decreases observed in phagocytic capacity. Unexpectedly, PA continued to be detected on the phagosome in the absence of either isoform and even when all PLD activity was eliminated. However, a disorganized phagocytic cup was observed as visualized by imaging PA, F-actin, Rac1, an organizer of the F-actin network, and DOCK2, a Rac1 activator, suggesting that PLD-mediated PA production during phagocytosis is specifically critical for the integrity of the process. The abnormal F-actin reorganization additionally impacted neutrophil migration and extravasation from the vasculature into interstitial tissues. Although both PLD1 and PLD2 were important in these processes, we also observed isoform-specific functions. PLD1-driven processes in particular were observed to be critical in transmigration of macrophages exiting the vasculature during immune responses such as those seen in acute pancreatitis or irritant-induced skin vascularization.
    MeSH term(s) Animals ; Blotting, Western ; Cytoskeleton/immunology ; Cytoskeleton/physiology ; Macrophages/immunology ; Mice ; Neuropeptides/metabolism ; Neutrophil Infiltration/immunology ; Pancreatitis/immunology ; Phagocytosis/immunology ; Phosphatidic Acids/metabolism ; Phospholipase D/deficiency ; rac GTP-Binding Proteins/metabolism ; rac1 GTP-Binding Protein
    Chemical Substances Neuropeptides ; Phosphatidic Acids ; Rac1 protein, mouse ; phospholipase D2 (EC 3.1.4.-) ; Phospholipase D (EC 3.1.4.4) ; phospholipase D1 (EC 3.1.4.4) ; rac GTP-Binding Proteins (EC 3.6.5.2) ; rac1 GTP-Binding Protein (EC 3.6.5.2)
    Language English
    Publishing date 2013-01-28
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ISSN 1932-6203
    ISSN (online) 1932-6203
    DOI 10.1371/journal.pone.0055325
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Identification and manipulation of biliary metaplasia in pancreatic tumors.

    Delgiorno, Kathleen E / Hall, Jason C / Takeuchi, Kenneth K / Pan, Fong Cheng / Halbrook, Christopher J / Washington, M Kay / Olive, Kenneth P / Spence, Jason R / Sipos, Bence / Wright, Christopher V E / Wells, James M / Crawford, Howard C

    Gastroenterology

    2013  Volume 146, Issue 1, Page(s) 233–44.e5

    Abstract: Background & aims: Metaplasias often have characteristics of developmentally related tissues. Pancreatic metaplastic ducts are usually associated with pancreatitis and pancreatic ductal adenocarcinoma. The tuft cell is a chemosensory cell that responds ... ...

    Abstract Background & aims: Metaplasias often have characteristics of developmentally related tissues. Pancreatic metaplastic ducts are usually associated with pancreatitis and pancreatic ductal adenocarcinoma. The tuft cell is a chemosensory cell that responds to signals in the extracellular environment via effector molecules. Commonly found in the biliary tract, tuft cells are absent from normal murine pancreas. Using the aberrant appearance of tuft cells as an indicator, we tested if pancreatic metaplasia represents transdifferentiation to a biliary phenotype and what effect this has on pancreatic tumorigenesis.
    Methods: We analyzed pancreatic tissue and tumors that developed in mice that express an activated form of Kras (Kras(LSL-G12D/+);Ptf1a(Cre/+) mice). Normal bile duct, pancreatic duct, and tumor-associated metaplasias from the mice were analyzed for tuft cell and biliary progenitor markers, including SOX17, a transcription factor that regulates biliary development. We also analyzed pancreatic tissues from mice expressing transgenic SOX17 alone (ROSA(tTa/+);Ptf1(CreERTM/+);tetO-SOX17) or along with activated Kras (ROSAtT(a/+);Ptf1a(CreERTM/+);tetO-SOX17;Kras(LSL-G12D;+)).
    Results: Tuft cells were frequently found in areas of pancreatic metaplasia, decreased throughout tumor progression, and absent from invasive tumors. Analysis of the pancreatobiliary ductal systems of mice revealed tuft cells in the biliary tract but not the normal pancreatic duct. Analysis for biliary markers revealed expression of SOX17 in pancreatic metaplasia and tumors. Pancreas-specific overexpression of SOX17 led to ductal metaplasia along with inflammation and collagen deposition. Mice that overexpressed SOX17 along with Kras(G12D) had a greater degree of transformed tissue compared with mice expressing only Kras(G12D). Immunofluorescence analysis of human pancreatic tissue arrays revealed the presence of tuft cells in metaplasia and early-stage tumors, along with SOX17 expression, consistent with a biliary phenotype.
    Conclusions: Expression of Kras(G12D) and SOX17 in mice induces development of metaplasias with a biliary phenotype containing tuft cells. Tuft cells express a number of tumorigenic factors that can alter the microenvironment. Expression of SOX17 induces pancreatitis and promotes Kras(G12D)-induced tumorigenesis in mice.
    MeSH term(s) Animals ; Bile Ducts/cytology ; Bile Ducts/metabolism ; Carcinoma, Pancreatic Ductal/complications ; Carcinoma, Pancreatic Ductal/metabolism ; Carcinoma, Pancreatic Ductal/pathology ; Cell Transformation, Neoplastic/metabolism ; Cell Transformation, Neoplastic/pathology ; HMGB Proteins/metabolism ; Humans ; Metaplasia/complications ; Metaplasia/metabolism ; Metaplasia/pathology ; Mice ; Mice, Transgenic ; Pancreatic Ducts/cytology ; Pancreatic Ducts/metabolism ; Pancreatic Ducts/pathology ; Pancreatic Neoplasms/complications ; Pancreatic Neoplasms/metabolism ; Pancreatic Neoplasms/pathology ; Pancreatitis/metabolism ; Precancerous Conditions/metabolism ; Precancerous Conditions/pathology ; Proto-Oncogene Proteins p21(ras)/metabolism ; SOXF Transcription Factors/metabolism ; Signal Transduction
    Chemical Substances HMGB Proteins ; SOXF Transcription Factors ; Sox17 protein, mouse ; Hras protein, mouse (EC 3.6.5.2) ; Proto-Oncogene Proteins p21(ras) (EC 3.6.5.2)
    Language English
    Publishing date 2013-08-30
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 80112-4
    ISSN 1528-0012 ; 0016-5085
    ISSN (online) 1528-0012
    ISSN 0016-5085
    DOI 10.1053/j.gastro.2013.08.053
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: EGF receptor is required for KRAS-induced pancreatic tumorigenesis.

    Ardito, Christine M / Grüner, Barbara M / Takeuchi, Kenneth K / Lubeseder-Martellato, Clara / Teichmann, Nicole / Mazur, Pawel K / Delgiorno, Kathleen E / Carpenter, Eileen S / Halbrook, Christopher J / Hall, Jason C / Pal, Debjani / Briel, Thomas / Herner, Alexander / Trajkovic-Arsic, Marija / Sipos, Bence / Liou, Geou-Yarh / Storz, Peter / Murray, Nicole R / Threadgill, David W /
    Sibilia, Maria / Washington, M Kay / Wilson, Carole L / Schmid, Roland M / Raines, Elaine W / Crawford, Howard C / Siveke, Jens T

    Cancer cell

    2012  Volume 22, Issue 3, Page(s) 304–317

    Abstract: Initiation of pancreatic ductal adenocarcinoma (PDA) is definitively linked to activating mutations in the KRAS oncogene. However, PDA mouse models show that mutant Kras expression early in development gives rise to a normal pancreas, with tumors forming ...

    Abstract Initiation of pancreatic ductal adenocarcinoma (PDA) is definitively linked to activating mutations in the KRAS oncogene. However, PDA mouse models show that mutant Kras expression early in development gives rise to a normal pancreas, with tumors forming only after a long latency or pancreatitis induction. Here, we show that oncogenic KRAS upregulates endogenous EGFR expression and activation, the latter being dependent on the EGFR ligand sheddase, ADAM17. Genetic ablation or pharmacological inhibition of EGFR or ADAM17 effectively eliminates KRAS-driven tumorigenesis in vivo. Without EGFR activity, active RAS levels are not sufficient to induce robust MEK/ERK activity, a requirement for epithelial transformation.
    MeSH term(s) ADAM Proteins/genetics ; ADAM Proteins/metabolism ; ADAM17 Protein ; Animals ; Carcinoma, Pancreatic Ductal/genetics ; Carcinoma, Pancreatic Ductal/metabolism ; Carcinoma, Pancreatic Ductal/pathology ; Cell Line, Tumor ; Cell Transformation, Neoplastic ; Epithelial Cells ; ErbB Receptors/biosynthesis ; ErbB Receptors/genetics ; ErbB Receptors/metabolism ; Extracellular Signal-Regulated MAP Kinases/metabolism ; Genes, ras ; Humans ; Mice ; Mice, Transgenic ; Pancreas/metabolism ; Pancreas/pathology ; Pancreatic Neoplasms/genetics ; Pancreatic Neoplasms/metabolism ; Pancreatic Neoplasms/pathology ; Proto-Oncogene Proteins p21(ras)/biosynthesis ; Proto-Oncogene Proteins p21(ras)/genetics ; Proto-Oncogene Proteins p21(ras)/metabolism
    Chemical Substances ErbB Receptors (EC 2.7.10.1) ; Extracellular Signal-Regulated MAP Kinases (EC 2.7.11.24) ; ADAM Proteins (EC 3.4.24.-) ; ADAM17 Protein (EC 3.4.24.86) ; ADAM17 protein, human (EC 3.4.24.86) ; Adam17 protein, mouse (EC 3.4.24.86) ; Hras protein, mouse (EC 3.6.5.2) ; Proto-Oncogene Proteins p21(ras) (EC 3.6.5.2)
    Language English
    Publishing date 2012-09-05
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 2078448-X
    ISSN 1878-3686 ; 1535-6108
    ISSN (online) 1878-3686
    ISSN 1535-6108
    DOI 10.1016/j.ccr.2012.07.024
    Database MEDical Literature Analysis and Retrieval System OnLINE

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