title: Neutrophil interactions with sialyl Lewis X on human nonsmall cell lung carcinoma cells regulate invasive behavior.
abstract: BACKGROUND
  The carbohydrate sialyl Lewis X (sLeX) is expressed on leukocytes and carcinoma cells and binds to selectins during inflammatory processes and early metastasis. Synthesis of sLeX depends on activity of enzymes, including α(1,3/1,4) fucosyltransferase (FucT-III). Tumor necrosis factor-α (TNF-α) up-regulates FucT-III, resulting in increased sLeX in the airways of patients with respiratory disease; however, the mechanisms that regulate sLeX in the inflammatory tumor microenvironment are not well understood.
  
  
  METHODS
  The authors stably transfected human lung carcinoma cell lines with the FucT-III gene and exposed them to TNF-α to investigate its role in regulation of sLeX expression and selectin-binding ability using semiquantitative real-time polymerase chain reaction and flow cytometry. Cytokine expression was examined in transfected cells using chemiluminescent arrays and enzyme-linked immunosorbent assays, and invasion was studied using Matrigel assays and alterations in morphology. Human lung tissue arrays were analyzed for immunohistochemical detection of sLeX and neutrophils.
  
  
  RESULTS
  Stimulation of FucT-III-transfected cells with recombinant human (rh) TNF-α up-regulated sLeX expression and increased E-selectin binding. Transfected cells secreted high levels of interleukin 8, growth-regulated oncogene-α, and mast cell proteinase-1. Cells exposed to rhTNF-α, neutrophil-conditioned media, and cultures with a 5:1 ratio of neutrophils to cancer cells had significantly increased sLeX expression and invasiveness and underwent nonadherent morphologic changes. In lung carcinomas, but not in normal lung tissues, 71% of tumors were highly positive for sLeX expression in areas of increased neutrophil infiltration.
  
  
  CONCLUSIONS
  The current results indicated that neutrophils may be recruited to areas of FucT-III activity and sLeX expression in lung carcinomas to enhance the invasive and metastatic potential of lung cancer cells.
authors: Department of Veterinary Clinical Sciences, University of Minnesota, Veterinary Medical Center, St. Paul, Minnesota, USA. sthil001@umn.edu
authors: Catherine A
authors: CA
authors: St Hill
authors: Katherine
authors: K
authors: Krieser
authors: Mariya
authors: M
authors: Farooqui
mesh_terms: D015153:Blotting, Western; D002289:Carcinoma, Non-Small-Cell Lung / Q000276:immunology* / Q000378:metabolism / Q000473:pathology*; D019040:E-Selectin / Q000235:genetics / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay; D005434:Flow Cytometry; D005647:Fucosyltransferases / Q000235:genetics / Q000378:metabolism; D006801:Humans; D007124:Immunoenzyme Techniques; D008175:Lung Neoplasms / Q000276:immunology* / Q000378:metabolism / Q000473:pathology*; D009361:Neoplasm Invasiveness; D009504:Neutrophils / Q000276:immunology* / Q000378:metabolism; D009844:Oligosaccharides / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D000080506:Sialyl Lewis X Antigen; D014407:Tumor Cells, Cultured; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics / Q000378:metabolism
chemical_list: D019040:E-Selectin; D009844:Oligosaccharides; D012333:RNA, Messenger; D000080506:Sialyl Lewis X Antigen; D014409:Tumor Necrosis Factor-alpha; D005647:Fucosyltransferases; C019818:3-galactosyl-N-acetylglucosaminide 4-alpha-L-fucosyltransferase