title: Regulation of colorectal cancer cell epithelial to mesenchymal transition by the renin angiotensin system.
abstract: OBJECTIVE
  Epithelial to mesenchymal transition (EMT) is implicated in tumor progression. We aimed to determine if the renin angiotensin system has a role in colorectal cancer (CRC) cell EMT.
  
  
  METHODS
  Human CRC cell lines DLD-1 and LIM2405 were used in wound scratch migration assays where they were treated with renin angiotensin system peptide ANG II alone or with blockers of ANG II type 1 or 2 receptors (AT1R and AT2R). Levels of epithelial (E-cadherin), mesenchymal (ZEB1, Vimentin) markers, inducible nitric oxide synthase (iNOS), and MMP9 were determined by flow cytometry. Mice bearing CRC liver metastases and treated with blockers for AT1R or AT2R were examined for ZEB1 and iNOS by immunohistochemistry.
  
  
  RESULTS
  ANG II increased in-vitro CRC cell migration in both cell lines, this was inhibited by AT1R (IRB) or AT2R blockade (PD123319). DLD-1 cells treated with AT1R blocker resulted in increased E-cadherin, reduced ZEB1, and Vimentin expression compared with ANG II-treated cells. Treatment with AT2R blocker decreased E-cadherin, no change in ZEB1 or Vimentin expression. AT1R blockade increased iNOS and decreased MMP9 expression in DLD-1 and LIM2405 cells. AT2R blockade decreased iNOS and MMP9 expression in both cell lines. In vivo, ZEB1 staining was higher in ANG II-treated animals compared with control and AT1R blockade treated animals, while activation of the AT2R led to an increase in iNOS compared with control and AT1R blockade.
  
  
  CONCLUSIONS
  ANG II-induced migration of CRC cells via both AT1 and AT2 receptors; the AT1R-mediated effects were associated with changes typical of EMT.
authors: Department of Surgery, The University of Melbourne, Austin Health, Melbourne, Victoria, Australia. linh.nguyen@unimelb.edu.au.
authors: Linh
authors: L
authors: Nguyen
authors: Department of Surgery, The University of Melbourne, Austin Health, Melbourne, Victoria, Australia.
authors: Eleanor I
authors: EI
authors: Ager
authors: Department of Surgery, The University of Melbourne, Austin Health, Melbourne, Victoria, Australia.
authors: Jaclyn
authors: J
authors: Neo
authors: Department of Surgery, The University of Melbourne, Austin Health, Melbourne, Victoria, Australia.
authors: Christopher
authors: C
authors: Christophi
mesh_terms: D000804:Angiotensin II / Q000494:pharmacology; D047228:Angiotensin II Type 1 Receptor Blockers / Q000494:pharmacology; D000818:Animals; D002465:Cell Movement / Q000187:drug effects; D015179:Colorectal Neoplasms / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology*; D058750:Epithelial-Mesenchymal Transition / Q000502:physiology*; D006801:Humans; D008113:Liver Neoplasms / Q000473:pathology / Q000556:secondary; D020780:Matrix Metalloproteinase 9 / Q000096:biosynthesis; D008808:Mice, Inbred CBA; D009363:Neoplasm Proteins / Q000378:metabolism; D009368:Neoplasm Transplantation; D052247:Nitric Oxide Synthase Type II / Q000378:metabolism; D044140:Receptor, Angiotensin, Type 1 / Q000378:metabolism; D044139:Receptor, Angiotensin, Type 2 / Q000378:metabolism; D012084:Renin-Angiotensin System / Q000502:physiology*; D014407:Tumor Cells, Cultured
chemical_list: D047228:Angiotensin II Type 1 Receptor Blockers; D009363:Neoplasm Proteins; D044140:Receptor, Angiotensin, Type 1; D044139:Receptor, Angiotensin, Type 2; D000804:Angiotensin II; C496319:NOS2 protein, human; D052247:Nitric Oxide Synthase Type II; C579270:MMP9 protein, human; D020780:Matrix Metalloproteinase 9
keywords: colorectal cancer; liver; metastases; migration