title: Loss of P53 Function Activates JAK2-STAT3 Signaling to Promote Pancreatic Tumor Growth, Stroma Modification, and Gemcitabine Resistance in Mice and Is Associated With Patient Survival.
abstract: One treatment strategy for pancreatic ductal adenocarcinoma is to modify, rather than deplete, the tumor stroma. Constitutive activation of the signal transducer and activator of transcription 3 (STAT3) is associated with progression of pancreatic and other solid tumors. We investigated whether loss of P53 function contributes to persistent activation of STAT3 and modification of the pancreatic tumor stroma in patients and mice.
  
  
  
  Stat3, Il6st (encodes gp130), or Trp53 were disrupted, or a mutant form of P53 (P53R172H) or transgenic sgp130 were expressed, in mice that developed pancreatic tumors resulting from expression of activated KRAS (KrasG12D, KC mice). Pancreata were collected and analyzed by immunohistochemistry, in situ hybridization, quantitative reverse-transcription polymerase chain reaction (qPCR), or immunoblot assays; fluorescence-activated cell sorting was performed to identify immune cells. We obtained frozen pancreatic tumor specimens from patients and measured levels of phosphorylated STAT3 and P53 by immunohistochemistry; protein levels were associated with survival using Kaplan-Meier analyses. We measured levels of STAT3, P53, ligands for gp130, interleukin 6, cytokines, sonic hedgehog signaling, STAT3 phosphorylation (activation), and accumulation of reactive oxygen species in primary pancreatic cells from mice. Mice with pancreatic tumors were given gemcitabine and a Janus kinase 2 (JAK2) inhibitor; tumor growth was monitored by 3-dimensional ultrasound.
  
  
  
  STAT3 was phosphorylated constitutively in pancreatic tumor cells from KC mice with loss or mutation of P53. Tumor cells of these mice accumulated reactive oxygen species and had lower activity of the phosphatase SHP2 and prolonged phosphorylation of JAK2 compared with tumors from KC mice with functional P53. These processes did not require the gp130 receptor. Genetic disruption of Stat3 in mice, or pharmacologic inhibitors of JAK2 or STAT3 activation, reduced fibrosis and the numbers of pancreatic stellate cells in the tumor stroma and altered the types of immune cells that infiltrated tumors. Mice given a combination of gemcitabine and a JAK2 inhibitor formed smaller tumors and survived longer than mice given control agents; the tumor stroma had fewer activated pancreatic stellate cells, lower levels of periostin, and alterations in collagen production and organization. Phosphorylation of STAT3 correlated with P53 mutation and features of infiltrating immune cells in human pancreatic tumors. Patients whose tumors had lower levels of phosphorylated STAT3 and functional P53 had significantly longer survival times than patients with high levels of phosphorylated STAT3 and P53 mutation.
  
  
  
  In pancreatic tumors of mice, loss of P53 function activates JAK2-STAT3 signaling, which promotes modification of the tumor stroma and tumor growth and resistance to gemcitabine. In human pancreatic tumors, STAT3 phosphorylation correlated with P53 mutation and patient survival time. Inhibitors of this pathway slow tumor growth and stroma formation, alter immune cell infiltration, and prolong survival of mice. Transcript profiling: ArrayExpress accession number: E-MTAB-3278.
authors.affiliation: II Medizinische Klinik, Klinikum Rechts der Isar, Technische Universität München, Munich, Germany.
authors.forename: Sonja M
authors.initials: SM
authors.lastname: Wörmann
authors.affiliation: II Medizinische Klinik, Klinikum Rechts der Isar, Technische Universität München, Munich, Germany.
authors.forename: Liang
authors.initials: L
authors.lastname: Song
authors.affiliation: II Medizinische Klinik, Klinikum Rechts der Isar, Technische Universität München, Munich, Germany.
authors.forename: Jiaoyu
authors.initials: J
authors.lastname: Ai
authors.affiliation: II Medizinische Klinik, Klinikum Rechts der Isar, Technische Universität München, Munich, Germany.
authors.forename: Kalliope N
authors.initials: KN
authors.lastname: Diakopoulos
authors.affiliation: II Medizinische Klinik, Klinikum Rechts der Isar, Technische Universität München, Munich, Germany.
authors.forename: Magdalena U
authors.initials: MU
authors.lastname: Kurkowski
authors.affiliation: II Medizinische Klinik, Klinikum Rechts der Isar, Technische Universität München, Munich, Germany.
authors.forename: Kivanc
authors.initials: K
authors.lastname: Görgülü
authors.affiliation: II Medizinische Klinik, Klinikum Rechts der Isar, Technische Universität München, Munich, Germany.
authors.forename: Dietrich
authors.initials: D
authors.lastname: Ruess
authors.affiliation: Beatson Institute for Cancer Research, University of Glasgow, Glasgow, United Kingdom.
authors.forename: Andrew
authors.initials: A
authors.lastname: Campbell
authors.affiliation: Pathology Unit, San Raffaele Scientific Institute, Ospedale San Raffaele, Milan, Italy.
authors.forename: Claudio
authors.initials: C
authors.lastname: Doglioni
authors.affiliation: Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Cambridge, United Kingdom.
authors.forename: Duncan
authors.initials: D
authors.lastname: Jodrell
authors.affiliation: Department of Gastroenterology, Endocrinology and Metabolism, Philipps-University, Marburg, Germany.
authors.forename: Albrecht
authors.initials: A
authors.lastname: Neesse
authors.affiliation: Chirurgische Klinik und Poliklinik, Klinikum Rechts der Isar, Technische Universität München, Munich, Germany.
authors.forename: Ihsan E
authors.initials: IE
authors.lastname: Demir
authors.affiliation: II Medizinische Klinik, Klinikum Rechts der Isar, Technische Universität München, Munich, Germany.
authors.forename: Angelica-Phaedra
authors.initials: AP
authors.lastname: Karpathaki
authors.affiliation: II Medizinische Klinik, Klinikum Rechts der Isar, Technische Universität München, Munich, Germany; German Cancer Consortium, German Cancer Research Center, Heidelberg, Germany.
authors.forename: Maxim
authors.initials: M
authors.lastname: Barenboim
authors.affiliation: Centre for Cancer and Inflammation, Barts Cancer Institute, Queen Mary University of London, John Vane Science Centre, London, United Kingdom.
authors.forename: Thorsten
authors.initials: T
authors.lastname: Hagemann
authors.affiliation: Institute of Biochemistry, Christian-Albrechts-University of Kiel, Kiel, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Rose-John
authors.affiliation: Beatson Institute for Cancer Research, University of Glasgow, Glasgow, United Kingdom.
authors.forename: Owen
authors.initials: O
authors.lastname: Sansom
authors.affiliation: II Medizinische Klinik, Klinikum Rechts der Isar, Technische Universität München, Munich, Germany.
authors.forename: Roland M
authors.initials: RM
authors.lastname: Schmid
authors.affiliation: Tumor Immunology Unit, San Raffaele Scientific Institute, Ospedale San Raffaele, Milan, Italy.
authors.forename: Maria P
authors.initials: MP
authors.lastname: Protti
authors.affiliation: II Medizinische Klinik, Klinikum Rechts der Isar, Technische Universität München, Munich, Germany.
authors.forename: Marina
authors.initials: M
authors.lastname: Lesina
authors.affiliation: II Medizinische Klinik, Klinikum Rechts der Isar, Technische Universität München, Munich, Germany. Electronic address: hana.alguel@mri.tum.de.
authors.forename: Hana
authors.initials: H
authors.lastname: Algül
mesh_terms: D000230:Adenocarcinoma / Q000188:drug therapy / Q000235:genetics*; D000818:Animals; D000964:Antimetabolites, Antineoplastic / Q000494:pharmacology; D021441:Carcinoma, Pancreatic Ductal / Q000188:drug therapy / Q000235:genetics*; D003841:Deoxycytidine / Q000031:analogs & derivatives / Q000494:pharmacology; D019008:Drug Resistance, Neoplasm; D016158:Genes, p53 / Q000502:physiology*; D006801:Humans; D053614:Janus Kinase 2 / Q000378:metabolism; D051379:Mice; D009154:Mutation; D010190:Pancreatic Neoplasms / Q000188:drug therapy / Q000235:genetics*; D010766:Phosphorylation / Q000235:genetics; D050796:STAT3 Transcription Factor / Q000378:metabolism; D015398:Signal Transduction / Q000235:genetics*; D000093542:Gemcitabine
chemical_list: D000964:Antimetabolites, Antineoplastic; D050796:STAT3 Transcription Factor; D003841:Deoxycytidine; D053614:Janus Kinase 2; D000093542:Gemcitabine
keywords: Mouse Model; PDAC; ROS; Shh