title: Chronic inflammation initiates multiple forms of K-Ras-independent mouse pancreatic cancer in the absence of TP53.
abstract: Chronic inflammation (CI) is a risk factor for pancreatic cancer (PC) including the most common type, ductal adenocarcinoma (PDAC), but its role and the mechanisms involved are unclear. To investigate the role of CI in PC, we generated genetic mouse models with pancreatic specific CI in the presence or absence of TP53. Mice were engineered to express either cyclooxygenase-2 (COX-2) or IκB kinase-2 (IKK2), and TP53+/+or TP53f/fspecifically in adult pancreatic acinar cells by using a full-length pancreatic elastase promoter-driven Cre. Animals were followed for >80 weeks and pancreatic lesions were evaluated histologically and immunohistochemically. The presence of K-ras mutations was assessed by direct sequencing, locked nuclei acid (LNA)-based PCR, and immunohistochemistry. We observed that sustained COX-2/IKK2 expression caused histological abnormalities of pancreas, including increased immune cell infiltration, proliferation rate and DNA damage. A minority of animals with CI developed pre-neoplastic lesions, but cancer was not observed in any TP53+/+animals within 84 weeks. In contrast, all animals with CI-lacking TP53 developed various subtypes of PC, including acinar cell carcinoma, ductal adenocarcinoma, sarcomatoid carcinoma and neuroendocrine tumors, and all died within 65 weeks. No evidence of K-ras mutations was observed. Variations in the activity of the Hippo, pERK and c-Myc pathways were found in the diverse cancer subtypes. In summary, chronic inflammation is extremely inefficient at inducing PC in the presence of TP53. However, in the absence of TP53, CI leads to the development of several rare K-ras-independent forms of PC, with infrequent PDAC. This may help explain the rarity of PDAC in persons with chronic inflammatory conditions.
authors.affiliation: Department of Cancer Biology, University of Texas, M.D. Anderson Cancer Center, Houston, TX, USA.|Department of Gastroenterology and Internal Medicine, University of Bialystok, Bialystok, Poland.
authors.forename: A K
authors.initials: AK
authors.lastname: Swidnicka-Siergiejko
authors.affiliation: Department of Cancer Biology, University of Texas, M.D. Anderson Cancer Center, Houston, TX, USA.
authors.forename: S B
authors.initials: SB
authors.lastname: Gomez-Chou
authors.affiliation: Department of Internal Medicine, Division of Gastroenterology, Hepatology and Nutrition, Ohio State University Wexner Medical Center, Columbus, OH, USA.
authors.forename: Z
authors.initials: Z
authors.lastname: Cruz-Monserrate
authors.affiliation: Department of Cancer Biology, University of Texas, M.D. Anderson Cancer Center, Houston, TX, USA.
authors.forename: D
authors.initials: D
authors.lastname: Deng
authors.affiliation: Department of Cancer Biology, University of Texas, M.D. Anderson Cancer Center, Houston, TX, USA.
authors.forename: Y
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Department of Cancer Biology, University of Texas, M.D. Anderson Cancer Center, Houston, TX, USA.|Department of Gastroenterology, Shanghai Hospital, Second Military Medical University, Shanghai, China.
authors.forename: H
authors.initials: H
authors.lastname: Huang
authors.affiliation: Department of Cancer Biology, University of Texas, M.D. Anderson Cancer Center, Houston, TX, USA.|Department of Biochemistry and Molecular Biology, Mayo Clinic, Jacksonville, FL, USA.
authors.forename: B
authors.initials: B
authors.lastname: Ji
authors.affiliation: Department of Cancer Biology, University of Texas, M.D. Anderson Cancer Center, Houston, TX, USA.
authors.forename: N
authors.initials: N
authors.lastname: Azizian
authors.affiliation: Department of Cancer Biology, University of Texas, M.D. Anderson Cancer Center, Houston, TX, USA.|Department of Gastroenterology and Internal Medicine, University of Bialystok, Bialystok, Poland.
authors.forename: J
authors.initials: J
authors.lastname: Daniluk
authors.affiliation: Department of GI Medical Oncology, University of Texas, M.D. Anderson Cancer Center, Houston, TX, USA.
authors.forename: W
authors.initials: W
authors.lastname: Lu
authors.affiliation: Department of Pathology, University of Texas, M.D. Anderson Cancer Center, Houston, TX, USA.
authors.forename: H
authors.initials: H
authors.lastname: Wang
authors.affiliation: Department of Translational Molecular Pathology, University of Texas, M.D. Anderson Cancer Center, Houston, TX, USA.
authors.forename: A
authors.initials: A
authors.lastname: Maitra
authors.affiliation: Department of Cancer Biology, University of Texas, M.D. Anderson Cancer Center, Houston, TX, USA.|Department of GI Medical Oncology, University of Texas, M.D. Anderson Cancer Center, Houston, TX, USA.
authors.forename: C D
authors.initials: CD
authors.lastname: Logsdon
mesh_terms: D000818:Animals; D021441:Carcinoma, Pancreatic Ductal / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D002908:Chronic Disease; D004195:Disease Models, Animal; D011905:Genes, ras; D007249:Inflammation / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D051379:Mice; D010190:Pancreatic Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D016283:Proto-Oncogene Proteins p21(ras) / Q000235:genetics / Q000378:metabolism*; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000378:metabolism*
chemical_list: D016159:Tumor Suppressor Protein p53; C495971:Hras protein, mouse; D016283:Proto-Oncogene Proteins p21(ras)