RESUMO
OBJECTIVE: The initial steps of pancreatic regeneration versus carcinogenesis are insufficiently understood. Although a combination of oncogenic Kras and inflammation has been shown to induce malignancy, molecular networks of early carcinogenesis remain poorly defined. DESIGN: We compared early events during inflammation, regeneration and carcinogenesis on histological and transcriptional levels with a high temporal resolution using a well-established mouse model of pancreatitis and of inflammation-accelerated KrasG12D-driven pancreatic ductal adenocarcinoma. Quantitative expression data were analysed and extensively modelled in silico. RESULTS: We defined three distinctive phases-termed inflammation, regeneration and refinement-following induction of moderate acute pancreatitis in wild-type mice. These corresponded to different waves of proliferation of mesenchymal, progenitor-like and acinar cells. Pancreas regeneration required a coordinated transition of proliferation between progenitor-like and acinar cells. In mice harbouring an oncogenic Kras mutation and challenged with pancreatitis, there was an extended inflammatory phase and a parallel, continuous proliferation of mesenchymal, progenitor-like and acinar cells. Analysis of high-resolution transcriptional data from wild-type animals revealed that organ regeneration relied on a complex interaction of a gene network that normally governs acinar cell homeostasis, exocrine specification and intercellular signalling. In mice with oncogenic Kras, a specific carcinogenic signature was found, which was preserved in full-blown mouse pancreas cancer. CONCLUSIONS: These data define a transcriptional signature of early pancreatic carcinogenesis and a molecular network driving formation of preneoplastic lesions, which allows for more targeted biomarker development in order to detect cancer earlier in patients with pancreatitis.
Assuntos
Carcinogênese/genética , Carcinoma Ductal Pancreático/genética , Neoplasias Pancreáticas/genética , Células Acinares/patologia , Doença Aguda , Animais , Carcinogênese/patologia , Carcinoma Ductal Pancreático/patologia , Proliferação de Células/genética , Modelos Animais de Doenças , Progressão da Doença , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Humanos , Células-Tronco Mesenquimais/patologia , Camundongos Transgênicos , Pâncreas/fisiologia , Neoplasias Pancreáticas/patologia , Pancreatite/genética , Pancreatite/patologia , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/patologia , Proteínas Proto-Oncogênicas p21(ras)/genética , Regeneração/genéticaRESUMO
BACKGROUND/OBJECTIVES: The small actin-binding protein destrin is one of the key regulators involved in remodeling of the actin cytoskeleton, a process crucial for cytokinesis, cell migration and polarized cell growth as well as for cancer cell migration and invasion. METHODS: A novel ex vivo nerve invasion model mirroring perineural cancer cell invasion as a key feature of pancreatic ductal adenocarcinoma has been previously established. Using this model, highly nerve-invasive clones of human pancreatic cancer cell lines have been obtained. Genome-wide transcriptional analyses of these cells revealed up-regulation of destrin in highly versus lowly nerve-invasive pancreatic cancer cells. RESULTS: Increased expression of destrin in these nerve-invasive cells was validated using quantitative RT-PCR and immunoblotting; concomitant changes in cell morphology were demonstrated using immunofluorescence analysis. Silencing of destrin by two specific siRNA oligonucleotides in Panc-1 pancreatic cancer cells decreased invasiveness and migration, and reduced proliferation of these cells. CONCLUSIONS: Destrin is upregulated in nerve-invasive pancreatic cancer cells and its expression might be related to perineural invasiveness.