title: Decreased levels of circulating regulatory NK cells in patients with head and neck cancer throughout all tumor stages.
abstract: BACKGROUND
  Natural killer (NK) cells play a crucial role in innate immunity as effectors against tumor cells and pathogen-infected cells. Human NK cells can be subdivided into two functional subsets, the immunoregulatory CD56(bright) NK cells and the cytotoxic CD56(dim) NK cells. NK-mediated host defence against tumor cells is strongly impaired in patients with head and neck squamous cell carcinoma (HNSCC).
  
  
  METHODS
  NK cells were isolated from peripheral blood of 70 HNSCC patients and 22 healthy donors by magnetic bead separation and subsequently analyzed using flow cytometric as well as immunohistochemical methods.
  
  
  RESULTS
  In this work we demonstrate that the population of circulating immunoregulatory CD56(bright) NK cells is lower in the peripheral blood of patients with HNSCC as compared with that in healthy donors, regardless of the individual tumor stage or tumor type.
  
  
  CONCLUSIONS
  These data underline the complex network of HNSCC-mediated immunomodulation as part of the immune escape mechanisms of malignant head and neck tumors.
authors: Department of Otorhinolaryngology, University of Schleswig-Holstein Campus Lübeck, 23538 Lübeck, Germany.
authors: Sandra
authors: S
authors: Wulff
authors: Ralph
authors: R
authors: Pries
authors: Kirsten
authors: K
authors: Börngen
authors: Thomas
authors: T
authors: Trenkle
authors: Barbara
authors: B
authors: Wollenberg
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D019002:CD56 Antigen / Q000378:metabolism*; D016022:Case-Control Studies; D005260:Female; D005434:Flow Cytometry; D006258:Head and Neck Neoplasms / Q000097:blood* / Q000473:pathology*; D006801:Humans; D007694:Killer Cells, Natural / Q000473:pathology*; D008297:Male; D008856:Microscopy, Fluorescence; D008875:Middle Aged; D009367:Neoplasm Staging; D055815:Young Adult
chemical_list: D019002:CD56 Antigen